外文翻译 - 英文
仓库优化外文专业翻译--英文翻译
Optimizing Warehouse ManagementJoe SciosciaHe is vice president of sales at VABody:The best practices of warehouse layout, management systems, and training are critical to implementing management solutions.warehouse solutions include both the software and hardware used to ensure accuracy of inventory and organization of product services, such as shipping, receiving, inventory management, product or service layout, staff, bins, and purchasing. Having the right software in place is an integral component to a pharmaceutical organization’s supply chain and is crucial to the success of overall business processes. Appropriate software simplifies inventory processing through automation, thus ensuring tight control and lot tracking at all levels of warehouse management, and meets pharmaceutical industry-specific regulations and institutional requirements.Measures for the management of the warehouse, of course, also contain other, such as the warehouse the goods storage area, in addition to the warehouse management personnel and the personnel related to the business need, anyone without approval shall not enter the warehouse. When entering the warehouse, the personnel must first go through the warehouse registration procedure and be accompanied by the warehouse personnel, not to enter the warehouse alone.Although software and the over- all warehouse management solution (WMS) are crucial tools, common mistakes can make it challenging to maintain a successful warehouse operation even when these tools are being used. Common problems include failure to put in place an efficient warehouse lay- out best suited to the products being handled, lack of knowledge of the inventory on hand, and inadequate preparation and training of personnel.Warehouse layoutIt may sound like a simple concept, but having a logical warehouse layout is par-amount to the success of any warehouse solution. Think of a warehouse like an architectural blueprint—an easy to navigate system where each section is clearly defined. Most warehouses store product materials in bins that are often scattered throughout the warehouse floor, which makes it challenging to find a product’s location and causes delays and errors in product shipment. To avoid this, companies can establish a naming convention for bins so warehouse staff can find things quickly and easily, thus creating a logical sequence to bring people to where they need to be. Name the bins and layout the warehouse in such a way that when someone looks at a bin tag, they will know how to find the bin.How well you and your staff know your products and inventory on hand will also help determine the warehouse layout and ultimate success of ware- house software. Place higher moving products near picking lanes that are close to shipping areas, place bulk areas in a location to facilitate bin replenishment, and determine logical areas for items that require cage, cooler, and vault storage. Be aware of how products are moving so that you can periodically re- arrange their location in the warehouse as needed. A good WMS will show how a system is performing and how products are coming in and going out.Within a pharmaceutical manufacturing facility, be sure to segregate products by keeping controlled substances in a locked area. Apply the same logic and flexibility to expensive, dangerous, or hazardous items that need to be kept in a specific place (i.e., safe zone). It is crucial for staff to keep records of date tracking, as most products have expiration dates,which could potentially result in ship- ping of outdated or near-date product.Warehouse management systemWarehouse management system is an important part of modern logistics management, ensure the timely supply of production needs, accelerate turnover, save the goods use, reduce cost and improve the economic benefits of enterprises plays an important role, so the warehouse management system has become an important part of modern company management system, it mainly includes the following several aspects: first, should according to outbound goods and goods management situation and the way of packaging planning the required location and area, make more efficient use of warehouse storage space. According to the different properties of the goods, the region shall be divided into two categories, s uch as goods of similar goods, inspection and non-conforming products to be stored in order to improve management. According to its name, specifications, quantity and so on, the goods are indicated on the material card or warehouse configuration diagram, and the inventory status is displayed at any time. Warehouse staff should master is the most important and dynamic of each location, product specification, and in accordance with the "first in first out, according to the batch outbound" the principle of setting inventory storage solutions, in principle should configure two or more small location each specification for used alternately, in turn to reach the requirement of first in first out.Personnel trainingAssigning and training personnel One of the most important components of developing a logical warehouse is the staff. The number of warehouse personnel will play a crucial role in operational effectiveness. With a large warehouse staff, consider organizing employees into smaller or specialized groups and assign specific employees to specific areas. Each situation will be unique based on the products a company is moving and the size of the staff.When investing in warehouse management software, it is important to test whether the software will operate with other existing technologies, such as RF scanners, and with automation systems, such as conveyors and carousels. Once a warehouse solution has been selected, tested, and implemented, employees should be trained on every component of the system to best maximize the warehouse solution investment and ensure that warehouse inventory is being moved and tracked in the most efficient manner. Whether it is bar code and radio-frequency (RF) data collection, returns, order management, or other software that is leveraged for warehouse management, personnel need to be trained and become comfort- able using this technology.The key to successfully implementing a warehouse solution and ensuring streamlined operations, automated processes, top efficiency, and reduced costs is to make sure that the most important assets—products and staff—are well prepared and organized in all areas of warehouse operations.Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.。
外文翻译---人工神经网络
英文文献英文资料：Artificial neural networks (ANNs) to ArtificialNeuralNetworks, abbreviations also referred to as the neural network (NNs) or called connection model (ConnectionistModel), it is a kind of model animals neural network behavior characteristic, distributed parallel information processing algorithm mathematical model. This network rely on the complexity of the system, through the adjustment of mutual connection between nodes internal relations, so as to achieve the purpose of processing information. Artificial neural network has since learning and adaptive ability, can provide in advance of a batch of through mutual correspond of the input/output data, analyze master the law of potential between, according to the final rule, with a new input data to calculate, this study analyzed the output of the process is called the "training". Artificial neural network is made of a number of nonlinear interconnected processing unit, adaptive information processing system. It is in the modern neuroscience research results is proposed on the basis of, trying to simulate brain neural network processing, memory information way information processing. Artificial neural network has four basic characteristics:(1) the nonlinear relationship is the nature of the nonlinear common characteristics. The wisdom of the brain is a kind of non-linear phenomena. Artificial neurons in the activation or inhibit the two different state, this kind of behavior in mathematics performance for a nonlinear relationship. Has the threshold of neurons in the network formed by the has better properties, can improve the fault tolerance and storage capacity.(2) the limitations a neural network by DuoGe neurons widely usually connected to. A system of the overall behavior depends not only on the characteristics of single neurons, and may mainly by the unit the interaction between the, connected to the. Through a large number of connection between units simulation of the brain limitations. Associative memory is a typical example of limitations.(3) very qualitative artificial neural network is adaptive, self-organizing, learning ability. Neural network not only handling information can have all sorts of change, and in the treatment of the information at the same time, the nonlinear dynamic system itself is changing. Often by iterative process description of the power system evolution.(4) the convexity a system evolution direction, in certain conditions will depend on a particular state function. For example energy function, it is corresponding to the extreme value of the system stable state. The convexity refers to the function extreme value, it has DuoGe DuoGe system has a stable equilibrium state, this will cause the system to the diversity of evolution.Artificial neural network, the unit can mean different neurons process of the object, such as characteristics, letters, concept, or some meaningful abstract model. The type of network processing unit is divided into three categories: input unit, output unit and hidden units. Input unit accept outside the world of signal and data; Output unit of output system processing results; Hidden unit is in input and output unit, not between by external observation unit. The system The connections between neurons right value reflect the connection between the unit strength, information processing and embodied in the network said the processing unit in the connections. Artificial neural network is a kind of the procedures, and adaptability, brain style of information processing, its essence is through the network of transformation and dynamic behaviors have akind of parallel distributed information processing function, and in different levels and imitate people cranial nerve system level of information processing function. It is involved in neuroscience, thinking science, artificial intelligence, computer science, etc DuoGe field cross discipline.Artificial neural network is used the parallel distributed system, with the traditional artificial intelligence and information processing technology completely different mechanism, overcome traditional based on logic of the symbols of the artificial intelligence in the processing of intuition and unstructured information of defects, with the adaptive, self-organization and real-time characteristic of the study.Development historyIn 1943, psychologists W.S.M cCulloch and mathematical logic W.P home its established the neural network and the math model, called MP model. They put forward by MP model of the neuron network structure and formal mathematical description method, and prove the individual neurons can perform the logic function, so as to create artificial neural network research era. In 1949, the psychologist put forward the idea of synaptic contact strength variable. In the s, the artificial neural network to further development, a more perfect neural network model was put forward, including perceptron and adaptive linear elements etc. M.M insky, analyzed carefully to Perceptron as a representative of the neural network system function and limitations in 1969 after the publication of the book "Perceptron, and points out that the sensor can't solve problems high order predicate. Their arguments greatly influenced the research into the neural network, and at that time serial computer and the achievement of the artificial intelligence, covering up development new computer and new ways of artificial intelligence and the necessity and urgency, make artificial neural network of research at a low. During this time, some of the artificial neural network of the researchers remains committed to this study, presented to meet resonance theory (ART nets), self-organizing mapping, cognitive machine network, but the neural network theory study mathematics. The research for neural network of research and development has laid a foundation. In 1982, the California institute of J.J.H physicists opfield Hopfield neural grid model proposed, and introduces "calculation energy" concept, gives the network stability judgment. In 1984, he again put forward the continuous time Hopfield neural network model for the neural computers, the study of the pioneering work, creating a neural network for associative memory and optimization calculation, the new way of a powerful impetus to the research into the neural network, in 1985, and scholars have proposed a wave ears, the study boltzmann model using statistical thermodynamics simulated annealing technology, guaranteed that the whole system tends to the stability of the points. In 1986 the cognitive microstructure study, puts forward the parallel distributed processing theory. Artificial neural network of research by each developed country, the congress of the United States to the attention of the resolution will be on jan. 5, 1990 started ten years as the decade of the brain, the international research organization called on its members will the decade of the brain into global behavior. In Japan's "real world computing (springboks claiming)" project, artificial intelligence research into an important component.Network modelArtificial neural network model of the main consideration network connection topological structure, the characteristics, the learning rule neurons. At present, nearly 40 kinds of neural network model, with back propagation network, sensor, self-organizing mapping, the Hopfieldnetwork.the computer, wave boltzmann machine, adapt to the ear resonance theory. According to the topology of the connection, the neural network model can be divided into:(1) prior to the network before each neuron accept input and output level to the next level, the network without feedback, can use a loop to no graph. This network realization from the input space to the output signal of the space transformation, it information processing power comes from simple nonlinear function of DuoCi compound. The network structure is simple, easy to realize. Against the network is a kind of typical prior to the network.(2) the feedback network between neurons in the network has feedback, can use a no to complete the graph. This neural network information processing is state of transformations, can use the dynamics system theory processing. The stability of the system with associative memory function has close relationship. The Hopfield network.the computer, wave ear boltzmann machine all belong to this type.Learning typeNeural network learning is an important content, it is through the adaptability of the realization of learning. According to the change of environment, adjust to weights, improve the behavior of the system. The proposed by the Hebb Hebb learning rules for neural network learning algorithm to lay the foundation. Hebb rules say that learning process finally happened between neurons in the synapse, the contact strength synapses parts with before and after the activity and synaptic neuron changes. Based on this, people put forward various learning rules and algorithm, in order to adapt to the needs of different network model. Effective learning algorithm, and makes the godThe network can through the weights between adjustment, the structure of the objective world, said the formation of inner characteristics of information processing method, information storage and processing reflected in the network connection. According to the learning environment is different, the study method of the neural network can be divided into learning supervision and unsupervised learning. In the supervision and study, will the training sample data added to the network input, and the corresponding expected output and network output, in comparison to get error signal control value connection strength adjustment, the DuoCi after training to a certain convergence weights. While the sample conditions change, the study can modify weights to adapt to the new environment. Use of neural network learning supervision model is the network, the sensor etc. The learning supervision, in a given sample, in the environment of the network directly, learning and working stages become one. At this time, the change of the rules of learning to obey the weights between evolution equation of. Unsupervised learning the most simple example is Hebb learning rules. Competition rules is a learning more complex than learning supervision example, it is according to established clustering on weights adjustment. Self-organizing mapping, adapt to the resonance theory is the network and competitive learning about the typical model.Analysis methodStudy of the neural network nonlinear dynamic properties, mainly USES the dynamics system theory and nonlinear programming theory and statistical theory to analysis of the evolution process of the neural network and the nature of the attractor, explore the synergy of neural network behavior and collective computing functions, understand neural information processing mechanism. In order to discuss the neural network and fuzzy comprehensive deal of information may, the concept of chaos theory and method will play a role. The chaos is a rather difficult toprecise definition of the math concepts. In general, "chaos" it is to point to by the dynamic system of equations describe deterministic performance of the uncertain behavior, or call it sure the randomness. "Authenticity" because it by the intrinsic reason and not outside noise or interference produced, and "random" refers to the irregular, unpredictable behavior, can only use statistics method description. Chaotic dynamics of the main features of the system is the state of the sensitive dependence on the initial conditions, the chaos reflected its inherent randomness. Chaos theory is to point to describe the nonlinear dynamic behavior with chaos theory, the system of basic concept, methods, it dynamics system complex behavior understanding for his own with the outside world and for material, energy and information exchange process of the internal structure of behavior, not foreign and accidental behavior, chaos is a stationary. Chaotic dynamics system of stationary including: still, stable quantity, the periodicity, with sex and chaos of accurate solution... Chaos rail line is overall stability and local unstable combination of results, call it strange attractor.A strange attractor has the following features: (1) some strange attractor is a attractor, but it is not a fixed point, also not periodic solution; (2) strange attractor is indivisible, and that is not divided into two and two or more to attract children. (3) it to the initial value is very sensitive, different initial value can lead to very different behavior.superiorityThe artificial neural network of characteristics and advantages, mainly in three aspects: first, self-learning. For example, only to realize image recognition that the many different image model and the corresponding should be the result of identification input artificial neural network, the network will through the self-learning function, slowly to learn to distinguish similar images. The self-learning function for the forecast has special meaning. The prospect of artificial neural network computer will provide mankind economic forecasts, market forecast, benefit forecast, the application outlook is very great. The second, with lenovo storage function. With the artificial neural network of feedback network can implement this association. Third, with high-speed looking for the optimal solution ability. Looking for a complex problem of the optimal solution, often require a lot of calculation, the use of a problem in some of the design of feedback type and artificial neural network, use the computer high-speed operation ability, may soon find the optimal solution.Research directionThe research into the neural network can be divided into the theory research and application of the two aspects of research. Theory study can be divided into the following two categories:1, neural physiological and cognitive science research on human thinking and intelligent mechanism.2, by using the neural basis theory of research results, with mathematical method to explore more functional perfect, performance more superior neural network model, the thorough research network algorithm and performance, such as: stability and convergence, fault tolerance, robustness, etc.; The development of new network mathematical theory, such as: neural network dynamics, nonlinear neural field, etc.Application study can be divided into the following two categories:1, neural network software simulation and hardware realization of research.2, the neural network in various applications in the field of research. These areas include: pattern recognition, signal processing, knowledge engineering, expert system, optimize the combination, robot control, etc. Along with the neural network theory itself and related theory, related to the development of technology, the application of neural network will further.Development trend and research hot spotArtificial neural network characteristic of nonlinear adaptive information processing power, overcome traditional artificial intelligence method for intuitive, such as mode, speech recognition, unstructured information processing of the defects in the nerve of expert system, pattern recognition and intelligent control, combinatorial optimization, and forecast areas to be successful application. Artificial neural network and other traditional method unifies, will promote the artificial intelligence and information processing technology development. In recent years, the artificial neural network is on the path of human cognitive simulation further development, and fuzzy system, genetic algorithm, evolution mechanism combined to form a computational intelligence, artificial intelligence is an important direction in practical application, will be developed. Information geometry will used in artificial neural network of research, to the study of the theory of the artificial neural network opens a new way. The development of the study neural computers soon, existing product to enter the market. With electronics neural computers for the development of artificial neural network to provide good conditions.Neural network in many fields has got a very good application, but the need to research is a lot. Among them, are distributed storage, parallel processing, since learning, the organization and nonlinear mapping the advantages of neural network and other technology and the integration of it follows that the hybrid method and hybrid systems, has become a hotspot. Since the other way have their respective advantages, so will the neural network with other method, and the combination of strong points, and then can get better application effect. At present this in a neural network and fuzzy logic, expert system, genetic algorithm, wavelet analysis, chaos, the rough set theory, fractal theory, theory of evidence and grey system and fusion.汉语翻译人工神经网络（ArtificialNeuralNetworks，简写为ANNs）也简称为神经网络（NNs）或称作连接模型（ConnectionistModel），它是一种模范动物神经网络行为特征，进行分布式并行信息处理的算法数学模型。
外文翻译中英文对照
Strengths优势All these private sector banks hold strong position on CRM part, they have professional, dedicated and well-trained employees.所以这些私人银行在客户管理部分都持支持态度，他们拥有专业的、细致的、训练有素的员工。
Private sector banks offer a wide range of banking and financial products and financial services to corporate and retail customers through a variety of delivery channels such as ATMs, Internet-banking, mobile-banking, etc. 私有银行通过许多传递通道（如自动取款机、网上银行、手机银行等）提供大范围的银行和金融产品、金融服务进行合作并向客户零售。
The area could be Investment management banking, life and non-life insurance, venture capital and asset management, retail loans such as home loans, personal loans, educational loans, car loans, consumer durable loans, credit cards, etc. 涉及的领域包括投资管理银行、生命和非生命保险、风险投资与资产管理、零售贷款（如家庭贷款、个人贷款、教育贷款、汽车贷款、耐用消费品贷款、信用卡等）。
Private sector banks focus on customization of products that are designed to meet the specific needs of customers. 私人银行主要致力于为一些特殊需求的客户进行设计和产品定制。
采矿工程 毕业设计_外文翻译 英译汉 中英文
ROOM-AND-PILLAR METHOD OF OPEN-STOPE MINING空场采矿法中的房柱采矿法Chapter 1.A Classification of the Room-and-Pillar Method of Open-Stope Mining第一部分，空场采矿的房柱法的分类OPEN STOPING空场采矿法An open stope is an underground cavity from which the initial ore has been mined. Caving of the opening is prevented (at least temporarily) by support from the unmined ore or waste left in the stope,in the form of pillars,and the stope walls (also called ribs or abutments). In addition to this primary may also be required using rockbolts , reinforcing rods, split pipes ,or shotcrete to stabilize the rock surface immediately adjacent to the opening. The secondary reinforcement procedure does not preclude the method classified as open stoping.露天采场台阶是开采了地下矿石后形成的地下洞室。
通过块矿或采场的支柱和（也称为肋或肩）采场墙形式的废料的支持来（至少是暂时的）预防放顶煤的开幕。
除了这个，可能还需要使用锚杆，钢筋棒，分流管，或喷浆，以稳定紧邻开幕的岩石表面。
语音识别中英文对照外文翻译文献
中英文资料对照外文翻译(文档含英文原文和中文翻译)Speech Recognition1 Defining the ProblemSpeech recognition is the process of converting an acoustic signal, captured by a microphone or a telephone, to a set of words. The recognized words can be the final results, as for applications such as commands & control, data entry, and document preparation. They can also serve as the input to further linguistic processing in order to achieve speech understanding, a subject covered in section.Speech recognition systems can be characterized by many parameters, some of the more important of which are shown in Figure. An isolated-word speech recognition system requires that the speaker pause briefly between words, whereas a continuous speech recognition system does not. Spontaneous, or extemporaneously generated, speech contains disfluencies, and is much more difficult to recognize than speech read from script. Some systems require speaker enrollment---a user must provide samples of his or her speech before using them, whereas other systems are said to be speaker-independent, in that no enrollment is necessary. Some of the other parameters depend on the specific task. Recognition is generally more difficult when vocabularies are large or have many similar-sounding words. When speech is produced in a sequence of words, language models or artificial grammars are used to restrict the combination of words.The simplest language model can be specified as a finite-state network, where the1permissible words following each word are given explicitly. More general language models approximating natural language are specified in terms of a context-sensitive grammar.One popular measure of the difficulty of the task, combining the vocabulary size and the language model, is perplexity, loosely defined as the geometric mean of the number of words that can follow a word after the language model has been applied (see section for a discussion of language modeling in general and perplexity in particular). Finally, there are some external parameters that can affect speech recognition system performance, including the characteristics of the environmental noise and the type and the placement of the microphone.Table: Typical parameters used to characterize the capability of speech recognition systems Speech recognition is a difficult problem, largely because of the many sources of variability associated with the signal. First, the acoustic realizations of phonemes, the smallest sound units of which words are composed, are highly dependent on the context in which they appear. These phonetic variabilities are exemplified by the acoustic differences of the phoneme，At word boundaries, contextual variations can be quite dramatic---making gas shortage sound like gash shortage in American English, and devo andare sound like devandare in Italian.Second, acoustic variabilities can result from changes in the environment as well as in the position and characteristics of the transducer. Third, within-speaker variabilities can result from changes in the speaker's physical and emotional state, speaking rate, or voice quality. Finally, differences in sociolinguistic background, dialect, and vocal tract size and shape can contribute to across-speaker variabilities.Figure shows the major components of a typical speech recognition system. The digitized speech signal is first transformed into a set of useful measurements or features at a fixed rate, typically once every 10--20 msec (see sectionsand 11.3 for signal representation and digital signal processing, respectively). These measurements are then used to search for the most likely word candidate, making use of constraints imposed by the acoustic, lexical, and language models. Throughout this process, training data are used to determine the values of the model parameters.Figure: Components of a typical speech recognition system.Speech recognition systems attempt to model the sources of variability described above in several ways. At the level of signal representation, researchers have developed representations that emphasize perceptually important speaker-independent features of the signal, and de-emphasize speaker-dependent characteristics. At the acoustic phonetic level, speaker variability is typically modeled using statistical techniques applied to large amounts of data. Speaker adaptation algorithms have also been developed that adapt speaker-independent acoustic models to those of the current speaker during system use, (see section). Effects of linguistic context at the acoustic phonetic level are typically handled by training separate models for phonemes in different contexts; this is called context dependent acoustic modeling.Word level variability can be handled by allowing alternate pronunciations of words in representations known as pronunciation networks. Common alternate pronunciations of words, as well as effects of dialect and accent are handled by allowing search algorithms to find alternate paths of phonemes through these networks. Statistical language models, based on estimates of the frequency of occurrence of word sequences, are often used to guide the searchthrough the most probable sequence of words.The dominant recognition paradigm in the past fifteen years is known as hidden Markov models (HMM). An HMM is a doubly stochastic model, in which the generation of the underlying phoneme string and the frame-by-frame, surface acoustic realizations are both represented probabilistically as Markov processes, as discussed in sections,and 11.2. Neural networks have also been used to estimate the frame based scores; these scores are then integrated into HMM-based system architectures, in what has come to be known as hybrid systems, as described in section 11.5.An interesting feature of frame-based HMM systems is that speech segments are identified during the search process, rather than explicitly. An alternate approach is to first identify speech segments, then classify the segments and use the segment scores to recognize words. This approach has produced competitive recognition performance in several tasks.2 State of the ArtComments about the state-of-the-art need to be made in the context of specific applications which reflect the constraints on the task. Moreover, different technologies are sometimes appropriate for different tasks. For example, when the vocabulary is small, the entire word can be modeled as a single unit. Such an approach is not practical for large vocabularies, where word models must be built up from subword units.Performance of speech recognition systems is typically described in terms of word error rate E, defined as:where N is the total number of words in the test set, and S, I, and D are the total number of substitutions, insertions, and deletions, respectively.The past decade has witnessed significant progress in speech recognition technology. Word error rates continue to drop by a factor of 2 every two years. Substantial progress has been made in the basic technology, leading to the lowering of barriers to speaker independence, continuous speech, and large vocabularies. There are several factors that have contributed to this rapid progress. First, there is the coming of age of the HMM. HMM is powerful in that, with the availability of training data, the parameters of the model can be trained automatically to giveoptimal performance.Second, much effort has gone into the development of large speech corpora for system development, training, and testing. Some of these corpora are designed for acoustic phonetic research, while others are highly task specific. Nowadays, it is not uncommon to have tens of thousands of sentences available for system training and testing. These corpora permit researchers to quantify the acoustic cues important for phonetic contrasts and to determine parameters of the recognizers in a statistically meaningful way. While many of these corpora (e.g., TIMIT, RM, ATIS, and WSJ; see section 12.3) were originally collected under the sponsorship of the U.S. Defense Advanced Research Projects Agency (ARPA) to spur human language technology development among its contractors, they have nevertheless gained world-wide acceptance (e.g., in Canada, France, Germany, Japan, and the U.K.) as standards on which to evaluate speech recognition.Third, progress has been brought about by the establishment of standards for performance evaluation. Only a decade ago, researchers trained and tested their systems using locally collected data, and had not been very careful in delineating training and testing sets. As a result, it was very difficult to compare performance across systems, and a system's performance typically degraded when it was presented with previously unseen data. The recent availability of a large body of data in the public domain, coupled with the specification of evaluation standards, has resulted in uniform documentation of test results, thus contributing to greater reliability in monitoring progress (corpus development activities and evaluation methodologies are summarized in chapters 12 and 13 respectively).Finally, advances in computer technology have also indirectly influenced our progress. The availability of fast computers with inexpensive mass storage capabilities has enabled researchers to run many large scale experiments in a short amount of time. This means that the elapsed time between an idea and its implementation and evaluation is greatly reduced. In fact, speech recognition systems with reasonable performance can now run in real time using high-end workstations without additional hardware---a feat unimaginable only a few years ago.One of the most popular, and potentially most useful tasks with low perplexity (PP=11) is the recognition of digits. For American English, speaker-independent recognition of digit strings spoken continuously and restricted to telephone bandwidth can achieve an error rate of 0.3% when the string length is known.One of the best known moderate-perplexity tasks is the 1,000-word so-called Resource Management (RM) task, in which inquiries can be made concerning various naval vessels in the Pacific ocean. The best speaker-independent performance on the RM task is less than 4%, using a word-pair language model that constrains the possible words following a given word (PP=60). More recently, researchers have begun to address the issue of recognizing spontaneously generated speech. For example, in the Air Travel Information Service (ATIS) domain, word error rates of less than 3% has been reported for a vocabulary of nearly 2,000 words and a bigram language model with a perplexity of around 15.High perplexity tasks with a vocabulary of thousands of words are intended primarily for the dictation application. After working on isolated-word, speaker-dependent systems for many years, the community has since 1992 moved towards very-large-vocabulary (20,000 words and more), high-perplexity (PP≈200), speaker-independent, continuous speech recognition. The best system in 1994 achieved an error rate of 7.2% on read sentences drawn from North America business news.With the steady improvements in speech recognition performance, systems are now being deployed within telephone and cellular networks in many countries. Within the next few years, speech recognition will be pervasive in telephone networks around the world. There are tremendous forces driving the development of the technology; in many countries, touch tone penetration is low, and voice is the only option for controlling automated services. In voice dialing, for example, users can dial 10--20 telephone numbers by voice (e.g., call home) after having enrolled their voices by saying the words associated with telephone numbers. AT&T, on the other hand, has installed a call routing system using speaker-independent word-spotting technology that can detect a few key phrases (e.g., person to person, calling card) in sentences such as: I want to charge it to my calling card.At present, several very large vocabulary dictation systems are available for document generation. These systems generally require speakers to pause between words. Their performance can be further enhanced if one can apply constraints of the specific domain such as dictating medical reports.Even though much progress is being made, machines are a long way from recognizing conversational speech. Word recognition rates on telephone conversations in the Switchboard corpus are around 50%. It will be many years before unlimited vocabulary, speaker-independentcontinuous dictation capability is realized.3 Future DirectionsIn 1992, the U.S. National Science Foundation sponsored a workshop to identify the key research challenges in the area of human language technology, and the infrastructure needed to support the work. The key research challenges are summarized in. Research in the following areas for speech recognition were identified:Robustness:In a robust system, performance degrades gracefully (rather than catastrophically) as conditions become more different from those under which it was trained. Differences in channel characteristics and acoustic environment should receive particular attention.Portability:Portability refers to the goal of rapidly designing, developing and deploying systems for new applications. At present, systems tend to suffer significant degradation when moved to a new task. In order to return to peak performance, they must be trained on examples specific to the new task, which is time consuming and expensive.Adaptation:How can systems continuously adapt to changing conditions (new speakers, microphone, task, etc) and improve through use? Such adaptation can occur at many levels in systems, subword models, word pronunciations, language models, etc.Language Modeling:Current systems use statistical language models to help reduce the search space and resolve acoustic ambiguity. As vocabulary size grows and other constraints are relaxed to create more habitable systems, it will be increasingly important to get as much constraint as possible from language models; perhaps incorporating syntactic and semantic constraints that cannot be captured by purely statistical models.Confidence Measures:Most speech recognition systems assign scores to hypotheses for the purpose of rank ordering them. These scores do not provide a good indication of whether a hypothesis is correct or not, just that it is better than the other hypotheses. As we move to tasks that require actions,we need better methods to evaluate the absolute correctness of hypotheses.Out-of-Vocabulary Words:Systems are designed for use with a particular set of words, but system users may not know exactly which words are in the system vocabulary. This leads to a certain percentage of out-of-vocabulary words in natural conditions. Systems must have some method of detecting such out-of-vocabulary words, or they will end up mapping a word from the vocabulary onto the unknown word, causing an error.Spontaneous Speech:Systems that are deployed for real use must deal with a variety of spontaneous speech phenomena, such as filled pauses, false starts, hesitations, ungrammatical constructions and other common behaviors not found in read speech. Development on the ATIS task has resulted in progress in this area, but much work remains to be done.Prosody:Prosody refers to acoustic structure that extends over several segments or words. Stress, intonation, and rhythm convey important information for word recognition and the user's intentions (e.g., sarcasm, anger). Current systems do not capture prosodic structure. How to integrate prosodic information into the recognition architecture is a critical question that has not yet been answered.Modeling Dynamics:Systems assume a sequence of input frames which are treated as if they were independent. But it is known that perceptual cues for words and phonemes require the integration of features that reflect the movements of the articulators, which are dynamic in nature. How to model dynamics and incorporate this information into recognition systems is an unsolved problem.语音识别一定义问题语音识别是指音频信号的转换过程，被电话或麦克风的所捕获的一系列的消息。
外文翻译(英文)
外文文献Gold refining technology introductionGold ore in the content is extremely low, in order to extract gold, need to will be broken and fine grinding ore and adopt。
With the mineral processing or enrichment from ore in advance that gold is isolated. Gold ore dressing is used in moreRe-election and flotation, re-election method in ShaJin production in an important position, flotation method is rock gold mine。
Widely use of mineral processing mountain, at present our country about 80% of the rock gold mines use this law to choose gold, choose。
Ore technology and equipment level is distinctly improved.(A) Broken and grindingAccording to the survey, our country choose gold in the jaw crusher for crushing, using standard cone broken. Ore machine broken, and finely used the short head type tapered roller machine and broken mine to break mine machine. Medium and small choose.Gold factory is used mostly for two broken a closed-circuit ore, large choose the three sections of a gold factory closed-circuit broken mine process. In order to improve the dressing production ability, mining equipment potential, broken mine to process, the reform.Grinding machine utilization coefficient increase, the major measures taken the little mill is broken, reduce ore into the ground particle size.(B) Re-electionRe-election in rock gold mine apply more extensive, and more as aided process, in the grinding loop of the recovery. Coarse grain of gold, for flotation and cyanide process to create favorable conditions, improve concentration index, improve the total return to gold. The yield, to increase production and reduce the cost is playing a positive role. Shandong province about more than 10 pick. Gold factory used heavy choose this one process, the average total recovery can be increased 2% ~ 3%, the enterprise economic effectGood profit, according to not complete count, may have millions of dollars a year of the profits. Henan, hunan, Inner Mongolia, etc. Provinces (areas) also have good effect, the main equipment is chute, wave bed, jig and short cone. Vortex machines etc. From our mostgold mine to see, float-heavy joint process (flotation tailings used heavy Choose) suitable for.(C) FlotationAccording to the survey, 80% of rock in the gold mines flotation method selected gold, the output of the concentrate more. Sent to non-ferrous smelter processing. Because of leaching gold cyanide process of development and enterprise to improve economic efficiency. Good, reduce concentrate transportation loss, in recent years the product structure has experienced a greater change, take more local processing (of course also because of mineral smelting and the contradiction between the problems and valuation, forcing the mine in situ to place Richard) prompted the flotation process have larger development, in the gold production occupies an important position in the. Usually Priority of flotation and mixing floatation two craft. In recent years in the process modification and potions add system .With new progress, flotation recoveries also increased significantly. More than 40 selected according to the national gold factory, flotation work.(D) The choose-leaching gold technology sector1. Mix mercury law of leaching goldMix mercury method of leaching gold process is a kind of old mention gold process, easy, and economic, and is suitable for coarse grains. Monomer recovery of gold. Our country many gold mine still follow the method. Along with the development of the gold production and the progress of science and technology, mix mercury law of leaching gold process is also constantly have improved and perfected. Due to the environment.The increasingly strict requirements, some mining cancelled mix mercury assignments, as heavy choose, the flotation and cyanide process of leaching gold.process replaced. In the gold production, mixed mercury method of leaching gold technology still has its important role in the domestic and foreign are should be with a practical example. At present in zhangjiakou, hebei province, liaoning erdaogou, jilin jiapigou, shandong etc many gold incorporated. Mine the process application. Liaoning erdaogou gold mine was a single flotation process, according to the ore properties instead.2. Of leaching gold cyanide process technologyCyanide process technology of leaching gold from oreconcentrate is modern or extraction of the main method of gold. Cyanide process mention.Gold technologies include: by roasting-cyanide leaching process, leaching of pulp washing filtering, kau liquid or are the cicc pulp.The extraction and the finished product and so on several basic processes of smelting. China's gold mines are the two basic existing factory. Kind of leaching gold process, one kind is dense continuous against washing machine, with zinc powder replacement precipitation back. The gold of so-called ordinary cyanide process of leaching gold process (CCD method and CCF law), the other is without filter washing, the active carbon adsorption in the pulp are directly from the recovery of gold without filter are carbon plasma process (CIP method and CIL law).Ordinary cyanide process of leaching gold process according to the different materials handled and two .(E) Heap leaching process for productionGold resources in China, low grade oxidation of ore has certain proportion, deal with this kind of ore.The routine of leaching gold cyanide process technology not economically viable, and the production process heap leaching, there are economic effect. The victims. Further expand the production scale heap leaching, is increase China's gold production of one of the path.20. At the end of the 70 s, China began to low grade contain gold ore heap leaching oxidation of the production process research, liaoning dandong hushan gold small-scale production trials are successful, successively in henan spirit lake, silver Hole slope, yunnan MoJiang, hebei worship ritual, Inner Mongolia and some of the mine in chifeng application, take more satisfactory economic effect, low grade for the gold ore containing the oxidation of the development and utilization of the opened up.。
外文翻译----柔性制造系统
外文翻译英文原文：Flexible Manufacturing SystemA logical step from the concepts of group layout and of NC machine tools and robotics are computer-controlled interlinked outstation machining complexes, or 11exibe manufacturing systems(FMS)as they have bedclothes call.do.Such systems can be looked upon as highly automated cells manufacturing families of components. The concept of FMS is not a new one; the first proposals were made in the mid 1960s. In recent years we have seen a growth in the number of systems, particularly in Japan, such that it is estimated that in excess of a hundred systems have been installed worldwide. A flexible manufacturing system contains a number of features as follows:1. Interlinked NC workstations operating on a limited range or family of work pieces. In early propos-ales the machines were of modular construction, but in recent systems general-purpose NC machines, in particular machining centers, are most commonly used.2. Automatic transportation, loading at unloading of work pieces and tools, using automatic guided vehicles (AGVs), robots,etc.3. Work pieces mounted on pallets ft* transportation, pattly to overcome the problems of new setups at each workstation.4. Centralized NC or DNC, together with overall computer control of the system.5. Operation for significant periods of time with little or no manual intervention.With FMS the tern flexibility means the ability to aptness a variety of components without having to adjust machine setups. Or change tooling. High flexibility implies that a large family of different components can be produced by the particular system. Figure 5. 17 show that several variants of the basic FMS con-kept exist. These are;l.Flexible manufacturing cells(FMs): These are basically machining centum but with the addition of a pallet pool or magazine(Fig.5. t8 ).The aim is to machine the work piece with one stupefies type of machine can be operated unmanned for long periods of time, with the palletized work pieces transformed au-somatically to and from the machine. Flexible manufacturing cells of this type must be served by machines or operators engaged in blank preparation and polarization of work pieces. These cells are highly flexible in operation, having the ability to deal with a wide range of pats (40 to 800), in small batches of from 15 to 500.2. Flexible transfer lines (fall): These, systems consist of a number of NC or head-changeable ma chine tools connected by automatic material transfer systems. The system can machine different components but without flexible routing of the workpieces.The family of components is relatively small (< 20) and the components must be quite similar to one another, as the overall flexibility of tote system is too low for a larger variety to be accommodated@. In consequence, the work cycles at each station nulls are quite well balanced. Production quantities must be quite large for economic use of these system (1 500 to 15000 per annum for each component).3. Flexible manufacturing systems (FMS), in these systems NC workstations are linked by automatic work piece transfer and handing. With flexible routing and automatic work piece loading and unloading. A-chining times at each station can differ considerably. The number of different components that can be pro-cussed by these systems is 'ohm 10 'o 150 in general and moderate quantities can be produced (15 to 500 components per annum for type)1．Work Handling for FMSWork pieces are usually mounted on standard pallets for processing in FMS and these pallets locate automatically at each workstation in the system. A variety of work-handling devices are used to transport parts, pallets, and tools around the system. Some of these ate as follows:1. Tow carts: These are the most cannon devices used; they consist of a simple platform on castors and are towed around the system by engagement with under floor, continuously moving chains. Cats stop at workstations by means of a mechanism total releases the tow pin at the appropriate time. Branches and loops are canalled in a similar manner to railway systems. 11te main advantage of tow carts is their simplicity and low cost, since no on-board power is required for their movement or control. Facilities must beavailable at each workstation to load and unload pallets from the carts. Also, the circulation of carts must be unidirectional.2. Automatic guided vehicles (AGVs). These devices are usually designed to follow wins buried in the floor of the plant or lines painted on tote floor. On-board power and control is required for bolt move mint and steering ate for tote handling of pallets. Automatic guided vehicles ate more expensive than tow cats and are both larger and heavier. Tale main advantage of AGVs is their greater flexibility of opera-ton. These devices may move in either direction, but for ease of control, circulation is usually restricted to one direction only in practice.3. Rail cats: These carts move on rails and are generally restricted to backward and forward motion along straight tracks. Power and control instructions ate ttunsferred by overhead conductors or extra rails.Rail carts often accommodate two pallets to allow for pallet exchange at the system workstations.4. Roller conveyors: Most of tote early FMS developments utilized powered-roller conveyors for moving work pieces from statuette to station. The use of these convents in modern systems is less common.Roller conveyors are expensive to install and occupy valuable floor space. In addition, these conveyors are relatively inflexible in operation and difficult to alter if the overall system is expanded.5. Industrial robots: Robots are used in FMS but not extensively unless the cell consists of only a few machines. They may be used as second at) handling devices, particularly for turned work pieces, which may be transported around the system in hatches on pallets by other handling devices and then transferred to the machine tool by robots at each workstation. Gripper designs suitable for handling a wide variety of components are important in this case.2．Layouts for FMSA variety of different layouts for the machine tools in FMS have been adopted, The choice depends on the scope of the system and the type of handling devices used for transporting work pieces from workstation to workstation. The use of rail carts mean that a straight track must be used, with machines located at the side of tote track. Early systems using roller conveyors usually employed a simple loop configura-tio11, with branches to the workstations.The increased use of tow carts and AGVs has resulted in more complex multicolor or tree-type layouts being used. The latter type is most suitable for AGVs and is particularly useful if expansion of the system with additional workstations is anticipated. Figure 5.19 shows a typical multicolor layout using tow carts, and Fig.5.20 shows a typical layout where AGVs are used for work handling.3．Factory of the FutureOn the basis of the advances made to date in all aspects of manufacturing technology and computer controls, we may envisage the factory of the future as a fully automated facility in which human beings would not be directly involved with production on the shop i1oor (hence the term unmanned factories).All manufacturing, material handling, assembly, and inspection would be done by automated and computer-controlled machinery and equipment.Similarly, activities such as processing incoming orders, production planning and scheduling, cost accounting, and various decision-making processes (usually performed by management) would also bedone automatically by computers. The role of human beings would be confined to activities such as supervising, maintaining (especially preventive maintenance), and upgrading machines and equipment; ship-ping and receiving supplies and finished products ; providing security for the plant facilities ; and programming, upgrading, and monitoring computer programs, and monitoring, maintaining, and upgrading hard-ware.Industries such as some food, petroleum, and chemical already operate automatically with little human intervention. These are continuous processes and, unlike piece part manufacturing, are easier to automate fully. Even so, the direct involvement of fewer people in manufacturing products is already apparent: Surveys show that; only 10-15 percent of the workforce is directly involved in production. Most of the workforce is involved in gathering and processing information.Virtually unmanned manufacturing cells already make products such as engine blocks, axles, and housings for clutches and air compressors .For large-scale, flexible manufacturing systems, however, highly trained and skilled personnel will always be needed to plan, maintain, and oversee operation.The reliability of machines, control systems, and power supply is crucial to full factory automation. A local or general breakdown in machinery, computers, power, or communications networks will, without rapid human intervention cripple production.The computer-integrated factory of the future should be capable of automatically rerouting materials and production flows to other computers in case of such emergencies.译文：柔性制造系统以成组布局的方式，将由计算机控制的多台数控机床及机器人结合成多工位成套加工设备，即称为柔性制造系统（FMS），这种系统被视为对各类零件族进行加工的高度自动化制造单元。
外文翻译格式
外文翻译原文1（中文宋体、英文Times New Roman Title of media choices, especially the Internet, prestige.Author （宋体小四顶格）：Nationality （宋体小四顶格）：Originate from （宋体小四顶格）：译文1（中文宋体、英文Times New Roman译文标题作者国籍（宋体小四顶格）：出处（宋体小四顶格）：附件3外文翻译原文1Information technology capability and valueInformation technology (IT) has become an essential element of firm capability and a source of sustainable competitive advantage. Although it is widely accepted that IT resources contribute to performance and future growth potential of the firm, the empirical results of the relationship between IT capability and firm performance is still ambiguous [1,2]. The unavailability of publicly available data, the accelerated pace of IT innovation,the possible interactive effects betweenHypothesis 2 predicts that the relationship between human capital investment and firm performance will be positive and results from all the five models strongly support this hypothesis.Alternative Hypotheses 3A and 3B predict the possible interaction effects of IT capability and human capital investment on firm performance. Results from Models 1, 2 and 3 support Hypothesis 3B.……作者：Zorayda Ruth B.Andam国籍：菲律宾出处：Amercan Management Association译文1信息技术能力和价值创造：来自美国银行业的实证信息技术已成为企业能力的一个重要组成部分和可持续竞争优势的资源之一。
成本控制中英文对照外文翻译文献
成本控制中英文对照外文翻译文献(文档含英文原文和中文翻译)原文：COST CONTROLRoger J. AbiNaderReference for Business，Encyclopedia of Business, 2nd ed.Cost control, also known as cost management or cost containment, is a broad set of cost accountingmethods and management techniques with the common goal of improving business cost-efficiency by reducing costs, or at least restricting their rate of growth. Businesses use cost control methods to monitor, evaluate, and ultimately enhance the efficiency of specific areas, such as departments, divisions, or product lines, within their operations.Control of the business entity , then, is essentially a managerial and supervisory function .Control consiets of those actions necessary to assur e that the entity’s resources and operations are focused on attaining established objectives , goals and plans. Control, exercised continuously, flags potential problems so that crises may be prevented. It also standardizeds the quantity of output , and provides managers with objective information about employee performance . Management compares actual performance to predetermined standards and takes action when necessary to correct variances from the standards.Keywords : Cost control, Applications, Control reports, Standards, Strategic Cost control, also known as cost management or cost containment, is a broad set of cost accountingmethods and management techniques with the common goal of improving business cost-efficiency by reducing costs, or at least restricting their rate of growth. Businesses use cost control methods to monitor, evaluate, and ultimately enhance the efficiency of specific areas, such as departments, divisions, or product lines, within their operations.During the 1990s cost control initiatives received paramount attention from corporate America. Often taking the form of corporate restructuring, divestmentof peripheral activities, mass layoffs,or outsourcing,cost control strategies were seen as necessary to preserve—or boost—corporate profits and to maintain—or gain—a competitive advantage. The objective was often to be the low-cost producer in a given industry, which would typically allow the company to take a greater profit per unit of sales than its competitors at a given price level.Some cost control proponents believe that such strategic cost-cutting must be planned carefully, as not all cost reduction techniques yield the same benefits. In a notable late 1990s example, chief executive Albert J. Dunlap, nicknamed "Chainsaw Al" because of his penchant for deep cost cutting at the companies he headed, failed to restore the ailing small appliance maker Sunbeam Corporation to profitability despite his drastic cost reduction tactics. Dunlap laid off thousands of workers and sold off business units, but made little contribution to Sunbeam's competitive position or share price in his two years as CEO. Consequently, in 1998 Sunbeam's board fired Dunlap, having lost confidence in his "one-trick" approach to management.COST CONTROL APPLICATIONSA complex business requires frequent information about operations in order to plan for the future, to control present activities, and to evaluate the past performance of managers, employees, and related business segments. To be successful, management guides the activities of its people in the operations of the business according to pre-established goal and objectives. Management’s guidance takestwo forms of control: (1) the management and supervision of behuvior , and (2) the evaluation of performance.Behavioral management deals with the attitudes and actions of employees. While employee behavior ultimately impacts on success, behavioral management involves certain issues and assumptions not applicable to accounting's control function. On the other hand, performance evaluation measures outcomes of employee's actions by comparing the actual results of business outcomes to predetermined standards ofsuccess. In this way management identifies the strengths it needs to maximize, and the weaknesses it seeks to rectify. This process of evaluation and remedy is called cost control.Cost control is a continuous process that begins with the proposed annual budget. The budget helps: (1) to organize and coordinate production, and the selling, distribution, service, and administrative functions; and (2) to take maximum advantage of available opportunities. As the fiscal year progresses, management compares actual results with those projected in the budget and incorporates into the new plan the lessons learned from its evaluation of current operations.Control refers to management's effort to influence the actions of individuals who are responsible for performing tasks, incurring costs, and generating revenues. Management is a two-phased process: planningrefers to the way that management plans and wants people to perform, while controlrefers to the procedures employed to determine whether actual performance complies with these plans. Through the budget process and accounting control, management establishes overall company objectives, defines the centers of responsibility, determines specific objectives for each responsibility center, and designs procedures and standards for reporting and evaluation.A budget segments the business into its components or centers where the responsible party initiates and controls action. Responsibility centersrepresent applicable organizational units, functions, departments, and divisions. Generally a single individual heads the responsibility center exercising substantial, if not complete, control over the activities of people or processes within the center and controlling the results of their activity. Cost centersare accountable only for expenses, that is, they do not generate revenue. Examples include accounting departments, human resources departments, and similar areas of the business that provide internal services. Profit centersaccept responsibility for both revenue and expenses. For example, a product line or an autonomous business unit might be considered profit centers. If the profit center has its own assets, it may also be considered an investment center,for which returns on investment can be determined. The use of responsibility centers allows management todesign control reports to pinpoint accountability, thus aiding in profit planning.A budget also sets standards to indicate the level of activity expected from each responsible person or decision unit, and the amount of resources that a responsible party should use in achieving that level of activity. A budget establishes the responsibility center, delegates the concomitant responsibilities, and determines the decision points within an organization.The planning process provides for two types of control mechanisms:Feedforward: providing a basis for control at the point of action (the decision point); andFeedback: providing a basis for measuring the effectiveness of control after implementation.Management's role is to feedforwarda futuristic vision of where the company is going and how it is to get there, and to make clear decisions coordinating and directing employee activities. Management also oversees the development of procedures to collect, record, and evaluate feedback.Therefore, effective management controls results from leading people by force of personality and through persuasion; providing and maintaining proper training, planning, and resources; and improving quality and results through evaluation and feedback.Control reports are informational reports that tell management about an entity's activities. Management requests control reports only for internal use, and, therefore, directs the accounting department to develop tailor-made reporting formats. Accounting provides management with a format designed to detect variations that need investigating. In addition, management also refers to conventional reports such as the income statement and funds statement, and external reports on the general economy and the specific industry.Control reports, then, need to provide an adequate amount of information so that management may determine the reasons for any cost variances from the original budget.A good control report highlights significant information by focusing management's attention on those items in which actual performance significantly differs from thestandard.Because key success factors shift in type and number, accounting revises control reports when necessary. Accounting also varies the control period covered by the control report toencompass a period in which management can take useful remedial action. In addition, accountingdisseminates control reports in a timely fashion to give management adequate time to act before the issuance of the next report.Managers perform effectively when they attain the goals and objectives set by the budget. With respect to profits, managers succeed by the degree to which revenues continually exceed expenses. In applying the following simple formula, managers, especially those in operations, realize that they exercise more control over expenses than they do over revenue.While they cannot predict the timing and volume of actual sales, they can determine the utilization rate of most of their resources, that is, they can influence the cost side. Hence, the evaluation of management's performance and its operations is cost control.For cost control purposes, a budget provides standard costs. As management constructs budgets, it lays out a road map to guide its efforts. It states a number of assumptions about the relationships and interaction among the economy, market dynamics, the abilities of its sales force, and its capacity to provide the proper quantity and quality of products demanded.Accounting plays a key role in all planning and control. It does this in four key areas: (1) data collection, (2) data analysis, (3) budget control and administration, and (4) consolidation and review.The accountants play a key role in designing and securing support for the procedural aspects of the planning process. In addition, they design and distribute forms for the collection and booking of detailed data on all aspects of the business.Although operating managers have the main responsibility of planning, accounting compiles and coordinates the elements. Accountants subject proposed budgets to feasibility and profitability analyses to determine conformity to accepted standards andpractices.Management relies on such accounting data and analysis to choose from several cost control alternatives, or management may direct accounting to prepare reports specifically for evaluating such options. As the Chainsaw Al episode indicated, all costs may not be viable targets for cost-cutting measures. For instance, in mass layoffs, the company may lose a significant share of its human capitalby releasing veteran employees who are experts in their fields, not to mention by creating a Decline in morale among those who remain. Thus management must identify which costs have strategic significance and which do not.To determine the strategic impact of cost-cutting, management has to weigh the net effects of the proposed change on all areas of the business. For example, reducing variable costs related directly to manufacturing a product, such as materials and transportation costs, could be the key to greater incremental profits. However, management must also consider whether saving money on production is jeopardizing other strategic interests like quality or time to market. If a cheaper material or transportation system negatively impacts other strategic variables, the nominal cost savings may not benefit the company in the bigger picture, e.g., it may lose sales. In such scenarios, managers require the discipline not to place short-term savings over long-term interests.One trend in cost control has been toward narrowing the focus of corporate responsibility centers, and thereby shifting some of the cost control function to day-to-day managers who have the most knowledge of and influence over how their areas spend money. This practice is intended to promote bottom-up cost control measures and encourage a widespread consensus over cost management strategies.Control of the business entity, then, is essentially a managerial and supervisory function. Control consists of those actions necessary to assure that the entity's resources and operations are focused on attaining established objectives, goals and plans. Control, exercised continuously, flags potential problems so that crises may be prevented. It also standardizes the quality and quantity of output, and provides managers with objectiveinformation about employee performance. Management compares actual performance to predetermined standards and takes action when necessary to correct variances from the standards.译文：成本控制成本控制成本控制，也被称为遏制成本或管理成本，一个广阔的成本管理技术，它的经济增长目标是降低成本提高企业效率。
外文翻译英文原文
Executive SummaryExtracted fromNIST NCSTAR 1-4 (Draft)Federal Building and Fire Safety Investigation of the World Trade Center DisasterActive Fire Protection Systems (Draft)E XECUTIVE S UMMARYIn the event of a fire in a building, the safety of occupants and first responders and the protection of property is accomplished through a combination of passive and active means. A passive fire protection system is one which is an integral part of the building layout and materials of construction, such as partitions to confine the fire, a stairway to assist rapid evacuation, or spray-on fire proofing to increase the fire resistance of a load-bearing steel structure. Active fire protection systems are designed to come into play only when a fire is present and require activation through a combination of sensors or mechanical means. The active fire protection systems in World Trade Center (WTC) 1, 2, and 7 consisted of fire sensors and alarms, notification systems, sprinklers, water supplies, and smoke management systems. Active and passive fire protection systems work together to control the spread of the fire and maintain the integrity of the structure; however, the fire department is always relied upon to fully extinguish the fire and rescue occupants who may be immobilized.The automatic fire sprinkler systems in WTC 1, 2, and 7 were the first line of defense. Water stored in the building from public sources or pumped from fire apparatus was supplied through dedicated piping to the area of the fire. Also present in the buildings were hoses, preconnected to a water supply through standpipes located in the stairwells and other utility shafts. The standpipes provided hose connections at each floor for The Fire Department of the City of New York (FDNY). In addition, standpipe preconnected hoses were installed for trained occupants to manually suppress fires.The heart of the fire detection system was the automatic fire alarm and emergency notification system. Occupants in the building depended on this system to detect fires and provide information for emergency evacuation. Capabilities were also designed for the ventilation system to operate in a way to purge smoke produced by fires from the building. Smoke purge was intended to be used for post-fire clean-up but could be used during a fire event at the discretion of the FDNY.This report includes an examination of the design and installation of the active fire protection systems in WTC 1, 2, and 7 and a description of the normal operation of fully functional systems and their potential effect on controlling the fires on September 11, 2001. The applicable building and fire codes and standards, as well as the history of fires in these buildings, are also documented.FIRESPRIOR TO SEPTEMBER 11, 2001E.1 SIGNIFICANTSignificant fires in WTC 1, 2, and 7 prior to September 11, 2001, were of interest to the investigation, particularly those that activated multiple sprinklers or where hoses were used to suppress the fires. Because the records of fire events in the buildings maintained by The Port Authority of New York and New Jersey (PANYNJ) were destroyed in the fire and collapse of WTC 1, information available for study was limited to that from FDNY fire and investigation reports.A major fire occurring in WTC 1 in 1975, prior to the installation of sprinklers, and the bombing of the WTC towers in 1993 were the most significant incidents in the history of these buildings. In addition,47 other fires were identified that were substantial enough to activate a sprinkler or require hoses to suppress the fire. Sixteen fire incidents exercised multiple sprinklers or multiple standpipe connectedExecutive Summary Draft for Public Comment hoses (with or without the activation of at least one sprinkler). Thirty-one fires involved the use of one standpipe hose or one standpipe hose and discharge of one sprinkler. Only three fires were identified to have occurred in WTC 7 prior to 2001. The FDNY fire reports and fire investigation records obtained by the National Institute of Standards and Technology (NIST) indicate that in areas protected by automatic sprinklers, no fire activated more than three sprinklers.AND PRECONNECTED HOSE SYSTEMS E.2 SPRINKLERS,STANDPIPES,The evaluation of the sprinklers, standpipes, and preconnected hose systems was performed by subject experts at Hughes Associates, Inc., under contract to NIST. The project documented the design, installation, and operation of the fire suppression systems in WTC 1, 2, and 7; evaluated the consistency of the sprinkler and standpipe systems installations with best engineering practices; described the New York City (NYC) water supply system and evaluated the sprinkler system water supply; and estimated suppression system performance when challenged with design fire scenarios assumed in standard engineering practice as well as with a fire scenario similar to that which occurred on September 11, 2001. Major features of the fire suppression systems are documented based on a review of the available information. In addition to describing in detail the sprinkler, standpipe, and preconnected hose systems, special fire suppression systems are briefly discussed. System features documented include riser systems, zone arrangements, water tanks, pumps, fire department connections, control valves, and hose rack arrangements. Additionally, documentation of the sprinkler, standpipe, and preconnected hose system installations was examined for consistency with the applicable installation standards and state-of-the-art engineering practices at the time of system installation.A description of the NYC water supply, including sizes, locations, and directions of water mains surrounding the WTC complex and distribution system within the buildings is provided to adequately evaluate the primary source of water for the automatic sprinkler and hose systems. Adequacy of the sprinkler system water supply was based on a detailed review of the available documentation. Flow capacity and duration of water supplies to the installed sprinkler systems were estimated using industry-accepted software. Hydraulic calculations were performed with variations in primary and secondary water supplies, the number of sprinklers flowing, and floor level elevations. The results from the calculations were used to evaluate the expected sprinkler system performance.Multiple fire scenarios were analyzed in order to more fully understand the potential impact of the suppression systems to provide the flow of water required to control typical office fires within high-rise buildings. The analysis included single fires on different floors in the towers and in WTC 7 with various combinations of sprinklers activated and with primary and secondary water supplies. Additionally, hydraulic calculations based on simultaneous fires on up to a total of nine floors were performed. Estimates of suppression system performance in WTC 1, 2, and 7 on September 11, 2001, were also made.The following list summarizes the findings of the suppression and water supply study:•Except for specific areas that were exempted from required sprinkler coverage, sprinklers were installed throughout WTC 1, 2, and 7 on September 11, 2001.Draft for Public Comment Executive Summary •According to the documentation examined, the fire suppression systems in WTC 1, 2, and 7 were installed, for the most part, in a manner consistent with state-of-the-art practices inexistence at the time of their installation. The installations as documented, with severalminor exceptions, would satisfy current best practices.•Storage tanks, along with direct connections to the NYC water distribution system, supplied water for WTC 1 and WTC 2, and for floors 21 through 47 of WTC 7. Fire suppressionsystems for floors 1 through 20 in WTC 7 were supplied directly through the NYC waterdistribution system and an automatic fire pump, with no secondary supply.•The installation of the supply piping from the storage tanks on the 110th floor in WTC 1 and WTC 2 resulted in restricted flow capacity to several floors. The flow capacity was sufficientto supply the suppression systems, but the installation was not consistent with currentengineering best practices.•The suppression systems in WTC 1, 2, and 7 required manual initiation of the electrical fire pumps in order to provide supplemental water. An automatic supplemental water supply hasbeen required by National Fire Protection Association (NFPA) 14 for some time andrepresents best practice. Due to extensive damage to the sprinkler and standpipe systems inWTC 1 and WTC 2 on September 11, 2001, it is doubtful that automatic pumps would havemade any difference in performance.•The supply risers for automatic sprinkler systems in WTC 1, 2, and 7 were configured to provide redundant capabilities. However, the sprinkler floor level controls were installedwith one connection to the sprinkler water riser. This represented a single point of failurelocation for the water supply to the sprinklers on that floor.•The water flow capacities of the sprinkler systems installed in WTC 1, 2, and 7 were designed to provide densities considerably greater than typically provided for high-rise officebuildings. Based on hydraulic calculations, it was estimated that the sprinkler systems couldhave controlled a typical fire at a coverage area up to two to three times the specific designarea of 1,500 ft2. However, a coverage area of 4,500 ft2 constitutes less than 15 percent ofthe area of a single floor.•The standpipe and preconnected hose systems were consistent with the applicable requirements in the Building Code of New York City (BCNYC). They were not consistentwith the flow rates and durations specified by NFPA 13.•The loading berth and fuel oil pump rooms in WTC 7 were protected by dry-pipe sprinkler systems. The first floor room containing the 6,000 gal fuel oil tank was protected by anInergen clean agent fire suppression system.•The fifth floor generator room was not equipped with a sprinkler system, consistent with the BCNYC. No information was found that indicated that the generator/fuel day-tankenclosures elsewhere in WTC 7 were protected by a fire suppression system.Executive Summary Draft for Public Comment •Primary and backup power were provided in all three buildings, but the absence of remote redundancy of the power lines to emergency fire pumps could have affected the operability ofthe sprinkler and standpipe systems once power was lost.•Due to the magnitude of the initial fires and the likely aircraft impact-induced damage sustained to the suppression systems infrastructures in WTC 1 and WTC 2, it is notunexpected that the suppression systems present in these buildings failed to control the fireson September 11, 2001.E.3 FIRE ALARM SYSTEMSThe evaluation of the fire alarm systems, a review of applicable codes and standards, documentation of the normal operation of fully functional fire alarm systems, and their potential performance in WTC 1, 2, and 7 on September 11, 2001, were performed by subject experts at Rolf Jensen and Associates, Inc., under contract to NIST.Major features of the fire alarm systems in WTC 1, 2, and 7 are described based on a review of the available documentation. Details on the fire command station, fire alarm system functions, fire alarm system installation criteria, control panel configurations, fire alarm devices, and firefighter telephone system are provided. Additionally, the staff emergency response plan that provided direction for emergency response is outlined. The responsibilities of the fire safety director, deputy fire directors, assistant fire safety coordinator, and floor wardens are described.For WTC 1 and WTC 2, performance on September 1, 2001, was documented based on brief images of illuminated status lamps on the system’s control panels, which were filmed during the event, and through interviews with people who were in the buildings at the time. The performance of the WTC 7 fire alarm system was assessed on the basis of the printout of the fire alarm system’s remote monitoring system.The following is a summary of findings based upon the review of the building designs and analysis of the various fire alarm systems:•Because the WTC 1 and WTC 2 fire alarm system required manual activation to notify building occupants, the alarm signal was delayed until 12 min after impact in WTC 1.•The telephone circuits and the notification appliance circuits were not required to have the same performance requirements as the signaling line circuits.•Attempts were made to use the firefighter telephone systems in WTC 1 and WTC 2 on September 11, 2001; however the system was not functioning.•Although the fire alarm systems in WTC 1 and WTC 2 used multiple communication path risers, the systems experienced performance degradation, especially in WTC 1 where all firealarm notification and communication functions appear to have been lost above the floors ofimpact.Draft for Public Comment Executive Summary •The fire alarm system installed in WTC 7 sent to the monitoring company only one signal indicating a fire condition in the building on September 11, 2001. This signal did not containany specific information about the location of the fire within the building.E.4 SMOKEMANAGEMENTSubject experts at Hughes Associates, Inc., under contract to NIST, evaluated the design and installation of the smoke management systems in WTC 1, 2, and 7, reviewed applicable codes and standards, and documented the normal operation of the fully functional smoke management systems and their potential effect on smoke conditions in WTC 1 and WTC 2 on September 11, 2001.The review of building codes and standards determined those that were applicable to WTC 1, 2, and 7. Specifically, the versions of BCNYC that applied and the local laws that were enacted which pertain to smoke management are presented. This review was used as a basis for documenting building designs and evaluating system performance. Descriptions are provided of the basic architecture of each building as it pertains to the establishment of smoke control zones, heating, ventilation and air-conditioning (HVAC) components and layout relevant to smoke management, and sequences of operation of smoke management systems (i.e., activation of fans and positioning of dampers to control airflow during smoke control operations).Smoke management system performance of WTC 1 and WTC 2 was evaluated based on the understanding of the systems developed during the design reviews. Analysis was performed using industry-accepted software to analyze the interaction between the building and the HVAC systems to determine the extent to which building pressures could be maintained in order to control or prevent the spread of smoke from a zone of fire origin to the rest of the building. The ability of the documented smoke management system to perform under typical design fire scenarios was analyzed along with the ability of the – assumed to be fully functional – system to perform given the damage sustained and the extreme fire/smoke conditions that developed as a result of aircraft impacts on the building.In order to more fully understand the potential impact of smoke management systems within high-rise buildings, multiple smoke management strategies, design fire scenarios, building configurations and weather conditions were analyzed. In total, a set of 180 simulations were performed, and results were evaluated.The following are findings from the evaluation of the smoke management systems:•The smoke management systems in WTC 1 and WTC 2 were not initiated onSeptember 11, 2001.•Had the smoke purge sequence been initiated in WTC 1 or WTC 2, it is unlikely the system would have functioned as designed, due to damage caused by aircraft impacts.•WTC 1 and WTC 2 were not required by the 1968 BCNYC, as amended by Local Law 5 and Local Law 86, to have active smoke and heat venting and/or stair pressurization because theycontained automatic sprinklers throughout.Executive Summary Draft for Public Comment •Even if fully operational, none of the potential smoke management systems evaluated would have prevented smoke spread given the damage caused by aircraft impact.•During the events occurring on September 11, 2001, stair pressurization would have been ineffective in improving conditions for occupants trying to exit the building.•Installation of combination fire/smoke dampers in HVAC ductwork, which was not required in WTC 1 or WTC 2, may have acted to slow the development of hazardous conditions on theuppermost floors of the building, but would likely not have had a significant effect on theability of occupants to egress the building due to the impassibility of the exit stairways.。
机器人外文文献翻译、中英文翻译
外文资料robotThe industrial robot is a tool that is used in the manufacturing environment to increase productivity. It can be used to do routine and tedious assembly line jobs，or it can perform jobs that might be hazardous to the human worker . For example ，one of the first industrial robot was used to replace the nuclear fuel rods in nuclear power plants. A human doing this job might be exposed to harmful amounts of radiation. The industrial robot can also operate on the assembly line，putting together small components，such as placing electronic components on a printed circuit board. Thus，the human worker can be relieved of the routine operation of this tedious task. Robots can also be programmed to defuse bombs，to serve the handicapped，and to perform functions in numerous applications in our society.The robot can be thought of as a machine that will move an end-of-tool ，sensor ，and/or gripper to a preprogrammed location. When the robot arrives at this location，it will perform some sort of task .This task could be welding，sealing，machine loading ，machine unloading，or a host of assembly jobs. Generally，this work can be accomplished without the involvement of a human being，except for programming and for turning the system on and off.The basic terminology of robotic systems is introduced in the following:1. A robot is a reprogrammable ，multifunctional manipulator designed to move parts，material，tool，or special devices through variable programmed motions for the performance of a variety of different task. This basic definition leads to other definitions，presented in the following paragraphs，that give acomplete picture of a robotic system.2. Preprogrammed locations are paths that the robot must follow to accomplish work，At some of these locations，the robot will stop and perform some operation ，such as assembly of parts，spray painting ，or welding .These preprogrammed locations are stored in the robot’s memory and are recalled later for continuousoperation.Furthermore，these preprogrammed locations，as well as other program data，can be changed later as the work requirements change.Thus，with regard to this programming feature，an industrial robot is very much like a computer ，where data can be stoned and later recalled and edited.3. The manipulator is the arm of the robot .It allows the robot to bend，reach，and twist.This movement is provided by the manipulator’s axes，also called the degrees of freedom of the robot .A robot can have from 3 to 16 axes.The term degrees of freedom will always relate to the number of axes found on a robot.4. The tooling and frippers are not part the robotic system itself;rather，they are attachments that fit on the end of the robot’s arm. These attachments connected to the end of the robot’s arm allow the robot to lift parts，spot-weld ，paint，arc-weld，drill，deburr，and do a variety of tasks，depending on what is required of the robot.5. The robotic system can control the work cell of the operating robot.The work cell of the robot is the total environment in which the robot must perform itstask.Included within this cell may be the controller ，the robot manipulator ，a work table ，safety features，or a conveyor.All the equipment that is required in order for the robot to do its job is included in the work cell .In addition，signals from outside devices can communicate with the robot to tell the robot when it should parts，pick up parts，or unload parts to a conveyor.The robotic system has three basic components: the manipulator，the controller，and the power source.A.ManipulatorThe manipulator ，which does the physical work of the robotic system，consists of two sections:the mechanical section and the attached appendage.The manipulator also has a base to which the appendages are attached.Fig.1 illustrates the connectionof the base and the appendage of a robot.图1.Basic components of a robot’s manipulatorThe base of the manipulator is usually fixed to the floor of the work area. Sometimes，though，the base may be movable. In this case，the base is attached to either a rail or a track，allowing the manipulator to be moved from one location to anther.As mentioned previously ，the appendage extends from the base of the robot. The appendage is the arm of the robot. It can be either a straight ，movable arm or a jointed arm. The jointed arm is also known as an articulated arm.The appendages of the robot manipulator give the manipulator its various axes of motion. These axes are attached to a fixed base ，which，in turn，is secured to a mounting. This mounting ensures that the manipulator will in one location.At the end of the arm ，a wrist（see Fig 2）is connected. The wrist is made up of additional axes and a wrist flange. The wrist flange allows the robot user to connect different tooling to the wrist for different jobs.图2.Elements of a work cell from the topThe manipulator’s axes allow it to perform work within a certain area. The area is called the work cell of the robot ，and its size corresponds to the size of the manipulator.（Fid2）illustrates the work cell of a typical assembly ro bot.As the robot’s physical size increases，the size of the work cell must also increase.The movement of the manipulator is controlled by actuator，or drive systems.The actuator，or drive systems，allows the various axes to move within the work cell. The drive system can use electric，hydraulic，or pneumatic power.The energy developed by the drive system is converted to mechanical power by various mechanical power systems.The drive systems are coupled through mechanical linkages.These linkages，in turn，drive the different axes of the robot.The mechanical linkages may be composed of chain，gear，and ball screws.B.ControllerThe controller in the robotic system is the heart of the operation .The controller stores preprogrammed information for later recall，controls peripheral devices，and communicates with computers within the plant for constant updates in production.The controller is used to control the robot manipulator’s movements as well as to control peripheral components within the work cell. The user can program the movements of the manipulator into the controller through the use of a hard-held teach pendant.This information is stored in the memory of the controller for later recall.The controller stores all program data for the robotic system.It can store several differentprograms，and any of these programs can be edited.The controller is also required to communicate with peripheral equipment within the work cell. For example，the controller has an input line that identifies when a machining operation is completed.When the machine cycle is completed，the input line turn on telling the controller to position the manipulator so that it can pick up the finished part.Then ，a new part is picked up by the manipulator and placed into the machine.Next，the controller signals the machine to start operation.The controller can be made from mechanically operated drums that step through a sequence of events.This type of controller operates with a very simple robotic system.The controllers found on the majority of robotic systems are more complex devices and represent state-of-the-art eletronoics.That is，they are microprocessor-operated.these microprocessors are either 8-bit，16-bit，or 32-bit processors.this power allows the controller to be very flexible in its operation.The controller can send electric signals over communication lines that allow it to talk with the various axes of the manipulator. This two-way communication between the robot manipulator and the controller maintains a constant update of the end the operation of the system.The controller also controls any tooling placed on the end of the robot’s wrist.The controller also has the job of communicating with the different plant computers. The communication link establishes the robot as part a computer-assisted manufacturing （CAM）system.As the basic definition stated，the robot is a reprogrammable，multifunctional manipulator.Therefore，the controller must contain some of memory stage. The microprocessor-based systems operates in conjunction with solid-state devices.These memory devices may be magnetic bubbles，random-access memory，floppy disks，or magnetic tape.Each memory storage device stores program information fir or for editing.C.power supplyThe power supply is the unit that supplies power to the controller and the manipulator. The type of power are delivered to the robotic system. One type of power is the AC power for operation of the controller. The other type of power isused for driving the various axes of the manipulator. For example，if the robot manipulator is controlled by hydraulic or pneumatic drives，control signals are sent to these devices causing motion of the robot.For each robotic system，power is required to operate the manipulator .This power can be developed from either a hydraulic power source，a pneumatic power source，or an electric power source.There power sources are part of the total components of the robotic work cell.中文翻译机器人工业机器人是在生产环境中用以提高生产效率的工具，它能做常规乏味的装配线工作，或能做那些对于工人来说是危险的工作，例如，第一代工业机器人是用来在核电站中更换核燃料棒，如果人去做这项工作，将会遭受有害放射线的辐射。
外文翻译 英文
2. WHAT CONSTITUTES FAIR DEALINGWEINBERGER v. UOP, INC.457 A.2d 701 (Del.Supr.19a3).MOORE, JUSTICE.This post-trial appeal was reheard en banc from a decision of the Court of Chancery. It was brought by the class action plaintiff below, a former shareholder of UOP, Inc., who challenged the elimination of UOP's minority shareholders by a cash-out merger between UOP and its majority owner, The Signal Companies, Inc. Originally, the defendants in this action were Signal, UOP, certain officers and directors of those companies, and UOP's investment banker, Lehman Brothers Kuhn Loeb, Inc. The present Chancellor held that the terms of the merger were fair to the plaintiff and the other minority shareholders of UOP. Accordingly, he entered judgment in favor of the defendants.Numerous points were raised by the parties, but we address only the following questions presented by the trial court's opinion:1) The plaintiffs duty to plead sufficient facts demonstrating the unfairness of the challenged merger;2) The burden of proof upon the parties where the merger has been approved by the purportedly informed vote of a majority of the minority shareholders;3) The fairness of the merger in terms of adequacy of the defendants' disclosures to the minority shareholders;4) The fairness of the merger in terms of adequacy of the price paid for the minority shares and the remedy appropriate to that issue; and5) The continued force and effect of Singer v. Magnavox Co., Del.Supr., 380 A.2d 969, 980 (1977), and its progeny.In ruling for the defendants, the Chancellor re-stated his earlier conclusion that the plaintiff in a suit challenging a cash-out merger must allege specific acts of fraud, misrepresentation or other items of misconduct to demonstrate the unfairness of the merger terms to the minority. We approve this rule and affirm it.The Chancellor also held that even though the ultimate burden of proof is on the majority shareholder to show by a preponderance of the evidence that the transaction is fair, it is first the burden of the plaintiff attacking the merger to demonstrate some basis for invoking the fairness obligation. We agree with that principle. However, where corporate action has been approved by an informed vote of a majority of the minority shareholders, we conclude that the burden entirely shifts ^ to the plaintiff to show that the transaction was unfair to the minority^- But in all this, the burden clearly remains on those relying on the vote to show that they completely disclosed all material facts relevant to the transaction.Here, the record does not support a conclusion that the minority stockholder vote was an informed one. Material information, necessary to acquaint those shareholders with the bargaining positions of Signal and UOP, was withheld under circumstances amounting to a breach of fiduciary duty. We therefore conclude that this merger does not meet the test of fairness, at least as we address that concept, and no burden thus shifted to the plaintiff by reason of the minority shareholder vote. Accordingly, we reverse and remand for further proceedings consistent herewith.In considering the nature of the remedy available under our law to minority shareholders in a cash-out merger, we believe that it is, and hereafter should be, an appraisal under 8 Del.C. § 262 as hereinafter construed. We therefore overrule Lynch v. Vickers Energy Corp., Del. Supr., 429 A.2d 497 (1981) {Lynch II) to the extent that it purports to limit a stockholder's monetary relief to a specific damage formula. But to give full effect to section 262 within the framework of the General Corporation Law we adopt a more liberal, less rigid and stylized, approach to the valuation process than has heretofore been permitted by our courts. While the present state of these proceedings does not admit the plaintiff to the appraisal remedy per se, the practical effect of the remedy we do grant him will be co-extensive with the liberalized valuation and appraisal methods we herein approve for cases coming after this decision.Our treatment of these matters has necessarily led us to a reconsideration of the business purpose rule announced in the trilogy of Singer A v. Magnavox Co., supra; Tanzer v. International General Industries, JT > Inc., DeL.Supr., 379 A.2d 1121 (1977); and Roland International Corp. v. Najjar, Del.Supr., 407 A.2d 1032 (1979). For the reasons hereafter set forth we consider that the business purpose requirement of these cases v J is no longer the law of Delaware.The facts found by the trial court, pertinent to the issues before us, are supported by the record, and we draw from them as set out in the Chancellor's opinion.Signal is a diversified, technically based company operating through various subsidiaries. Its stock is publicly traded on the New York, Philadelphia and Pacific Stock Exchanges. UOP, formerly known as Universal Oil Products Company, was a diversified industrial company engaged in various lines of business, including petroleum and petro-chemical services and related products, construction, fabricated metal products, transportation equipment products, chemicals and plastics, and other products and services including land development, lumber products and waste disposal. Its stock was publicly held and listed on the New York Stock Exchange.In 1974 Signal sold one of its wholly-owned subsidiaries for $420,000,000 in cash. See Gimbel v. Signal Companies, Inc., Del.Ch., 316 A.2d 599, aff’d, Del.Supr., 316 A.2d 619 (1974). While looking to invest this cash surplus, Signal became interested in UOP as a possible acquisition. Friendly negotiations ensued, and Signal proposed to acquire a controlling interest in UOP at a price of $19 per share. UOP's representatives sought $25 per share. In the arm's length bargaining that followed, an understanding was reached whereby Signal agreed to purchase from UOP 1,500,000 shares of UOP's authorized but unissued stock at $21 per share.This purchase was contingent upon Signal^ making a successful cash tender offer for 4,300,000 publicly held shares of UOP, also at a price of $21 per share. This combined method of acquisition permitted Signal to acquire 5,800,000 shares of stock, representing 50.5% of UOP's outstanding shares. The UOP board of directors advised the company's shareholders that it had no objection to Signal's tender offer at that price. Immediately before the announcement of the tender offer, UOP's common stock had been trading on the New York Stock Exchange at a fraction under $14 per share.The negotiations between Signal and UOP occurred during April 1975, and the resulting tender offer was greatly oversubscribed. However, Signal limited its total purchase of the tendered shares so that, when coupled with the stock bought from UOP, it had achieved its goalof becoming a 50.5% shareholderAlthough UOP’ board consisted of thirteen directors, Signal nominated and elected only six. Of these, five were either directors or employees of Signal. The sixth, a partner in the banking firm of Lazard Freres & Co., had been one of Signal's representatives in the negotiations and bargaining with UOP concerning the tender offer and purchase price of the UOP shares.However, the president and chief executive officer of UOP retired during 1975, and Signal caused him to be replaced by James V. Crawford, a long-time employee and senior executive vice president of one of Signal's wholly-owned subsidiaries. Crawford succeeded his predecessor on UOP's board of directors and also was made a director of Signal.By the end of 1977 Signal basically was unsuccessful in finding other suitable investment candidates for its excess cash, and by February 1978 considered that it had no other realistic acquisitions available to it on a friendly basis. Once again its attention turned to UOP.The trial court found that at the instigation of certain Signal management personnel, including William W. Walkup, its board chairman, and Forrest N. Shumway, its president, a feasibility study was made concerning the possible acquisition of the balance of UOP's outstanding shares. This study was performed by two Signal officers, Charles S. Arledge, vice president (director of planning), and Andrew J. Chitiea, senior vice president (chief financial officer). Messrs. Walkup, Shumway, Arledge and Chitiea were all directors of UOP in addition to their membership on the Signal board.Arledge and Chitiea concluded that it would be a good investment for Signal to acquire the remaining 49.5% of UOP shares at any price up to $24 each. Their report was discussed between Walkup and Shumway who, along with Arledge, Chitiea and Brewster L. Arms, internal counsel for Signal, constituted Signal's senior management. In particular, they talked about the proper price to be paid if the acquisition was pursued, purportedly keeping in mind that as UOP's majority shareholder, Signal owed a fiduciary responsibility to both its own stockholders as well as to UOP's minority. It was ultimately agreed that a meeting of Signal's Executive Committee would be called to propose that Signal acquire the remaining outstanding stock of UOP through a cash-out merger in the range of $20 to $21 per share.The Executive Committee meeting was set for February 28, 1978. As a courtesy, UOP's president, Crawford, was invited to attend, although he was not a member of Signal's executive committee. On his arrival, and prior to the meeting, Crawford was asked to meet privately with Walkup and Shumway. He was then told of Signal's plan to acquire full ownership of UOP and was asked for his reaction to the proposed price range of $20 to $21 per share. Crawford said he thought such a price would be "generous", and that it was certainly one which should be submitted to UOP's minority shareholders for their ultimate consideration. He stated, however, that Signal's 100% ownership could cause internal problems at UOP. He believed that employees would have to be given some assurance of their future place in a fully- owned Signal subsidiary. Otherwise, he feared the departure of essential personnel. Also, many of UOP's key employees had stock option incentive programs which would be wiped out by a merger. Crawford therefore urged that some adjustment would have to be made, such as providing a comparable incentive in Signal's shares, if after the merger he was to maintain his quality of personnel and efficiency at UOP.Thus, Crawford voiced no objection to the $20 to $21 price range, nor did he suggest that Signal should consider paying more than $21 per share for the minority interests. Later, at the Executive Committee meeting the same factors were discussed, with Crawford repeating the position he earlier took with Walkup and Shumway. Also considered was the 1975 tender offer andthe fact that it had been greatly oversubscribed at $21 per share. For many reasons, Signal's manage¬ment concluded that the acquisition of UOP's minority shares provided the solution to a number of its business problems.Thus, it was the consensus that a price of $20 to $21 per share would be fair to both Signal and the minority shareholders of UOP. Signal's executive committee authorized its management "to negotiate" with UOP "for a cash acquisition of the minority ownership in UOP, Inc., with the intention of presenting a proposal to [Signal's] board of directors * * * on March 6, 1978". Immediately after this February 28, 1978 meeting, Signal issued a press release stating: The Signal Companies, Inc. and UOP, Inc. are conducting negotiations for the acquisition for cash by Signal of the 49.5 per cent of UOP which it does not presently own, announced Forrest N. Shumway, president and chief executive officer of Signal, and James V. Crawford, UOP president. Price and other terms of the proposed transaction have not y et been finalized and would be subject to approval of the boards of directors of Signal and UOP, scheduled to meet early next week, the stockholders of UOP and certain federal agencies.The announcement also referred to the fact that the closing price of UOP's common stock on that day was $14.50 per share.Two days later, on March 2, 1978, Signal issued a second press release stating that its management would recommend a price in the range of $20 to $21 per share for UOP's 49.5% minority interest. This announcement referred to Signal's earlier statement that "negotiations" were being conducted for the acquisition of the minority shares.Between Tuesday, February 28, 1978 and Monday, March 6,1978, a total of four business days, Crawford spoke by telephone with all of UOP's non-Signal, i.e., outside, directors. Also during that period, Crawford retained Lehman Brothers to render a fairness opinion as to the price offered the minority for its stock. He gave two reasons for this choice. First, the time schedule between the announcement and the board meetings was short (by then only three business days) and since Lehman Brothers had been acting as UOP's investment banker for many years, Crawford felt that it would be in the best position to respond on such brief notice. Second, James W. Glanville, a long-time director of UOP and a partner in Lehman Brothers, had acted as a financial advisor to UOP for many years. Crawford believed that Glanville's familiarity with UOP, as a member of its board, would also be of assistance in enabling Lehman Brothers to render a fairness opinion within the existing time constraints.Crawford telephoned Glanville, who gave his assurance that Lehman Brothers had no conflicts that would prevent it from accepting the task. Glanville's immediate personal reaction was that a price of $20 to $21 would certainly be fair, since it represented almost a 50% premium over UOP's market price. Glanville sought a $250,000 fee for Lehman Brothers' services, but Crawford thought this too much. After further discussions Glanville finally agreed that Lehman Brothers would render its fairness opinion for $150,000.During this period Crawford also had several telephone contacts with Signal officials. In only one of them, however, was the price of the shares discussed. In a conversation with Walkup, Crawford advised that as a result of his communications with UOP's non-Signal directors, it was his feeling that the price would have to be the top of the proposed range, or $21 per share, if the approval of UOP's outside directors was to be obtained. But again, he did not seek any price higher than $21.Glanville assembled a three-man Lehman Brothers team to do the work on the fairness opinion. These persons examined relevant documents and information concerning UOP, including its annual reports and its Securities and Exchange Commission filings from 1973 through 1976, as well as its audited financial statements for 1977, its interim reports to shareholders, and its recent and historical market prices and trading volumes. In addition, on Friday, March 3, 1978, two members of the Lehman Brothers team flew to UOP's headquarters in Des Plaines, Illinois, to perform a "due diligence" visit, during the course of which they interviewed Crawford as well as UOP's general counsel, its chief financial officer, and other key executives and personnel.As a result, the Lehman Brothers team concluded that "the price of either $20 or $21 would be a fair price for the remaining shares of UOP". They telephoned this impression to Glanville, who was spending the weekend in Vermont.On Monday morning, March 6, 1978, Glanville and the senior member of the Lehman Brothers team flew to Des Plaines to attend the scheduled UOP directors meeting. Glanville looked over the assembled information during the flight. The two had with them the draft of a "fairness opinion letter" in which the price had been left blank. Either during or immediately prior to the directors' meeting, the two-page "fairness opinion letter" was typed in final form and the price of $21 per share was inserted.On March 6, 1978, both the Signal and UOP boards were convened to consider the proposed merger. Telephone communications were maintained between the two meetings. Walkup, Signal's board chairman, and also a UOP director, attended UOP's meeting with Crawford in order to present Signal's position and answer any questions that UOP's non-Signal directors might have. Arledge and Chitiea, along with Signal's other designees on UOP's board, participated by conference telephone. All of UOP's outside directors attended the meeting either in person or by conference telephone.First, Signal's board unanimously adopted a resolution authorizing Signal to propose to UOP a cash merger of $21 per share as outlined in a certain merger agreement, and other supporting documents. This proposal required that the merger be approved by a majority of UOP's outstanding minority shares voting at the stockholders meeting at which the merger would be considered, and that the minority shares voting in favor of the merger, when coupled with Signal's 50.5% interest would have to comprise at least two-thirds of all UOP shares. Otherwise the proposed merger would be deemed disapproved.UOP's board then considered the proposal. Copies of the agreement were delivered to the directors in attendance, and other copies had been forwarded earlier to the directors participating by telephone. They also had before them UOP financial data for 1974-1977, UOP's most recent financial statements, market price information, and budget projections for 1978. In addition they had Lehman Brothers' hurriedly prepared fairness opinion letter finding the price of $21 to be fair. Glanville, the Lehman Brothers partner, and UOP director, commented on the information that had gone into preparation of the letter.Signal also suggests that the Arledge-Chitiea feasibility study, indicating that a price of up to $24 per share would be a "good investment" for Signal, was discussed at the UOP directors' meeting. The Chancellor made no such finding, and our independent review of the record, detailed infra, satisfies us by a preponderance of the evidence that there was no discussion of this document at UOP's board meeting. Furthermore, it is clear beyond peradventure that nothing in that report was ever disclosed to UOP's minority shareholders prior to their approval of themerger.After consideration of Signal's proposal, Walkup and Crawford left the meeting to permit a free and uninhibited exchange between UOP's non-Signal directors. Upon their return a resolution to accept Signal's offer was then proposed and adopted. While Signal's men on UOP's board participated in various aspects of the meeting, they abstained from voting. However, the minutes show that each of them "if voting would have voted yes".On March 7, 1978, UOP sent a letter to its shareholders advising them of the action taken by UOP's board with respect to Signal's offer. This document pointed out, among other things, that on February 28, 1978 "both companies had announced negotiations were being conducted".Despite the swift board action of the two companies, the merger was not submitted to UOP's shareholders until their annual meeting on May 26, 1978. In the notice of that meeting and proxy statement sent to shareholders in May, UOP's management and board urged that the merger be approved. The proxy statement also advised:The price was determined after discussions between James V. Crawford, a director of Signal and Chief Executive Officer of UOP, and officers of Signal which took place during meetings on February 28, 1978, and in the course of several subsequent telephone conversations. (Emphasis added.)In the original draft of the proxy statement the word "negotiations" had been used rather than "discussions". However, when the Securities and Exchange Commission sought details of the "negotiations" as part of its review of these materials, the term was deleted and the word "discussions" was substituted. The proxy statement indicated that the vote of UOP's board in approving the merger had been unanimous. It also advised the shareholders that Lehman Brothers had given its opinion that the merger price of $21 per share was fair to UOP's minority. However, it did not disclose the hurried method by which this conclusion was reached.As of the record date of UOP's annual meeting, there were 11,488,302 shares of UOP common stock outstanding, 5,688,302 of which were owned by the minority. At the meeting only 56%, or 3,208,652, of the minority shares were voted. Of these, 2,953,812, or 51.9% of the total minority, voted for the merger, and 254,840 voted against it. When Signal's stock was added to the minority shares voting in favor, a total of 76.2% of UOP's outstanding shares approved the merger while only 2.2% opposed it.By its terms the merger became effective on May 26, 1978, and each share of UOP's stock held by the minority was automatically converted into a right to receive $21 cash.II.A.A primary issue mandating reversal is the preparation by two UOP directors, Arledge and Chitiea, of their feasibility study for the exclusive use and benefit of Signal. This document was of obvious significance to both Signal and UOP. Using UOP data, it described the advantages to Signal of ousting the minority at a price range of $21-$24 per share. Mr. Arledge, one of the authors, outlined the benefits to Signal:Purpose Of The Merger1) Provides an outstanding investment opportunity for Signal—(Better than any recent acquisition we have seen.)2) Increases Signal's earnings.3) Facilitates the flow of resources between Signal and its subsidiaries(Big factor—works both ways.)4) Provides cost savings potential for Signal and UOP.5) Improves the percentage of Signal's 'operating earnings' as opposed to 'holding company earnings'.6) Simplifies the understanding of Signal.7) Facilitates technological exchange among Signal's subsidiaries.8) Eliminates potential conflicts of interest.Having written those words, solely for the use of Signal it is clear from the record that neither Arledge nor Chitiea shared this report with their fellow directors of UOP. We are satisfied that no one else did either. This conduct hardly meets the fiduciary standards applicable to such a transaction * * *The Arledge-Chitiea report speaks for itself in supporting the Chancellor's finding that a price of up to $24 was a "good investment" for Signal. It shows that a return on the investment at $21 would be 15.7% versus 15.5% at $24 per share. This was a difference of only two-tenths of one percent, while it meant over $17,000,000 to the minority. Under such circumstances, paying UOP's minority shareholders $24 would have had relatively little long-term effect on Signal, and the Chancellor's findings concerning the benefit to Signal, even at a price of $24, were obviously correct. Levitt v. Bouvier, Del.Supr., 287 A.2d 671, 673 (1972).Certainly, this was a matter of material significance to UOP and its shareholders. Since the study was prepared by two UOP directors, using UOP information for the exclusive benefit of Signal, and nothing whatever was done to disclose it to the outside UOP directors or the minority shareholders, a question of breach of fiduciary duty arises. This problem occurs because there were common Signal-UOP directors participating, at least to some extent, in the UOP board's decision making processes without full disclosure of the conflicts they faced.7B.In assessing this situation, the Court of Chancery was required to:examine what information defendants had and to measure it against what they gave to the minority stockholders, in a context in which 'complete candor' is required. In other words, the limited function of the Court was to determine whether defendants had disclosed all information in their possession germane to the transaction in issue. And by 'germane' we mean, for present purposes, information such as a reasonable shareholder would consider important. in Priding whether. to sell or retain stock.* * ** * * Completeness, not adequacy, is both the norm and the mandate under present circumstances. Lynch v. Vickers Energy Corp., Del.Supr., 383 A.2d 278, 281 (1977) (Lynch /). This is merely stating in another way the long-existing principle of Delaware law that these Signal designated directors on UOP's board still owed UOP and its shareholders an uncompromising duty of loyalty. The classic language of Guth v. Loft, Inc., Del.Supr., 5 A.2d 503, 510 (1939), requires no embellishment:A public policy, existing through the years, and derived from a profound knowledge of human characteristics and motives, has established a rule that demands of a corporate officer or director, peremptorily and inexorably, the most scrupulous observance of his duty, not only affirmatively to protect the interests of the corporation committed to his charge, but also to refrainfrom doing anything that would work injury to the corporation, or to deprive it of. profit or advantage which his skill and ability might properly bring to it, or to enable it to make in the reasonable and lawful exercise of its powers. The rule that requires an undivided and unselfish loyalty to the corporation demands that there shall be no conflict between duty and self-interest. Given the absence of any attempt to structure this transaction on an arm's length basis, Signal cannot escape the effects of the conflicts it faced, particularly when its designees on UOP's board did not totally abstain from participation in the matter. There is no "safe harbor" for such divided loyalties in Delaware. When directors of a Delaware ^ corporation are on both sides of a transaction, they are required to demonstrate their utmost good faith and the most scrupulous inherent P fairness of the bargain. Gottlieb v. Heyden Chemical Corp., Del.Supr., 91 A.2d 57, 57-58 (1952). The requirement of fairness is unflinching in v rP y demand that where one stands on both sides of a transaction, he has the burden of establishing its entire fairness, sufficient to pass the test of careful scrutiny by the courts. Sterling v. Mayflower Hotel Corp., N, Del.Supr., 93 A.2d 107, 110 (1952); Bastian v. Bourns, Inc., Del.Ch., 256 A.2d 680, 681 (1969), aff’d, Del.Supr., 278 A.2d 467 (1970); David J. Greene & Co. v. Dunhill International Inc., Del.Ch., 249 A.2d 427, 431 (1968).There is no dilution of this obligation where one holds dual or multiple directorships, as in a parent-subsidiary context. Levien v. Sinclair Oil Corp., Del.Ch., 261 A.2d 911, 915 (1969). Thus, individuals who act in a dual capacity as directors of two corporations, one of whom is parent and the other subsidiary, owe the same duty of good management to both corporations, and in the absence of an independent negotiating structure (see note 7, supra), or the directors' total abstention from any participation in the matter, this duty is to be exercised in light of what is best for both companies. Warshaw v. Calhoun, Del. Supr., 221 A.2d 487, 492 (1966). The record demonstrates that Signal has not met this obligation.。
外文翻译---国际贸易单证的作用
附录F.1英文参考资料及中文翻译F. 1 .1international trade documents roleGeneral international trade documents (international trade documents) is the international trade of use all the documents, documents and certificates collectively. Usually with international trade documents to deal with in and out of delivery of the goods El, transportation, insurance, inspection and quarantine, customs declaration, the settlement of exchange, etc. Special international trade documents usually refers to the settlement documents, especially the l/c under the way of settlement of documents.International trade documents and the use of import and export trade program closely related, the documents in the import and export enterprise work throughout the export, purchase, transportation, the whole process of the proceeds, the effort is big, timeliness strong, is broad, in addition to import and export enterprise internal between various departments the cooperation with the outside, still must and bank, customs, transportation department, insurance companies, the inspection and quarantine agencies and the relevant administrative authorities happen various contact, linked together, mutual influence, also are conditions.International trade documents for the performance of a contract is necessary meansInternational trade is the transnational goods business, due to the particularity of the multinational business, which is the purchase and sale of the different departments are located in different countries, are remote, in most cases, the goods and payment can't perform simple direct exchange, but only as the medium of exchange with documents means. The international trade of the documents that sales of goods through the documents realization sale, the seller should not only will the actual delivery of goods export shipment, and should submit to the buyer include the title to the goods vouchers, complete documents to show real assignment. The seller/p means that the delivery of the goods, and the buyer payment is get to buy goods on behalf of property rights certificate, the deal is no longer with the goods as the core, but with documents as the core. Documents and payment of the convection principle has become the international trade of general principles of the commodity business. As international trade experts "; m Cardiff in the export trade in his book mentioned: "from a business perspective, can say CIF the purpose of the contract is not the buying and selling of goods itself, but the documents relating to the goods business." What say here "documents" is the international trade of documents.International trade documents many kinds, every kind of documents has itsspecial role, functions and different prepared by requirements. In the import and export trade in the process of contract documents can be roughly divided into two kinds: one kind has the property of commodity. They represent some goods, some say the exchange value of commodity, some explain the packaging of goods content, some guarantee the quality and quantity of goods, some for commodities exempt from provide the essential proof, etc.; Another type of have monetary properties, they represent direct some money, some of the money to pay for to make a promise made conditional guarantee or. All the documents issued by, combined, circulation, exchange and application reflects the process of contract, it reflects the buyers and sellers of responsibility, transfer and termination happen. This shows, international trade documents is necessary to complete the contract.International trade documents is foreign trade business management important toolsInternational trade documents is involved in international trade by import and export enterprises and the relevant countries issued by the government organizations, from import and export enterprise perspective, the international trade documents the import and export of the work is an important link. The actual business, whether the contract contents, terms and conditions of the credit, or implement supply, delivery quality control, quantity, and transportation, insurance, inspection and quarantine, customs declaration, the settlement of exchange, and many other business management link, the final work in documents concentrated reflection out, also is the contract performance post processing the important basis of controversy and disputes.From the perspective of national, international trade documents as a foreign business and legal documents, reflected the one country foreign trade policy, reflects a country foreign trade related laws, regulations and rules and regulations, involved in one country and other countries of between bilateral or multilateral trade agreements, as members must abide by the related to the international organization of the relevant rules.Visible, import and export enterprise management stand or fall and work organization management quality documents relationship is very big, international trade documents work is not only the whole process service for trade, import and export enterprise management is an important tool, but also a country foreign trade management important tools.International trade documents import and export enterprise to improve the economic benefit is the important guaranteeInternational trade work and import and export documents the economic efficiency of enterprises closely related, the documents management work to strengthen and improve the quality of documents, not only can effectively stop mistakes accidents, make up for the defect of the management, also can accelerate the money collecting, increasing the service efficiency of funds, managing interest expenses, save all kinds of cost, express in the import and export enterprises improve economic benefit. If documents management work of any errors, failed to hand in single or provide the correct documents, it will lead to the buyer refuse to pay payment, delay payment, and then to the enterprise and even the country risks andlosses, the economic benefit of enterprise could not be guaranteed.International trade documents is the important content of import and export enterprise imageInternational trade is not only the business and legal documents documents, and still can rise to shape and perfect the import and export enterprise external image, foreign expanded publicity role. Beautiful, neat and clear the documents, can show import and export enterprise a high level of service quality, the high quality of the work product, and the first-class standard management standards, and for enterprise to mould good image, be helpful for business development. Conversely, poor, mixed and disorderly, the wrong documents is inevitable brings to the enterprise negative effect.Ticket, promissory notes, checks or other used for payment of money has similar documents; Commercial documents has the property of commodity, such as commercial invoice.(URC 522) classification model makes commercial documents category is quite widespread, covers the financial documents except outside of all documents, in fact commercial documents could further subdivided into basic documents and affiliate documents. Basic documents in real business use frequency is very high, usually including commercial invoice, ocean bill of lading and insurance policy; Affiliated usually in real business documents, according to the agreement of the buyer is required to provide the seller, can be divided into two kinds: one kind is the requirements of the importing country official documents, such as consular invoice, custom invoice, the certificate of origin, etc.; Another kind is the buyer requests that the goods and related documents, such as packing list and quality certificate, weight list, send docs proof, send samples proof, shipment notification, age certification, etc.F.2国际贸易单证的作用广义的国际贸易单证（international trade documents）是国际贸易中使用的各种单据、文件与证书的统称。
外文翻译--来自太阳的能源
英文资料ENERGY FROM THE SUNThe sun has produced energy for billions of years.Solar energy is the solar radiation that reaches the earth. Solar energy can be converted directly or indirectly into other forms of energy, such as heat and electricity.The major drawbacks (problems, or issues to overcome) of solar energy are: (1) the intermittent and variable manner in which it arrives at the earth's surface and, (2) the large area required to collect it at a useful rate. Solar energy is used for heating water for domestic use, space heating of buildings, drying agricultural products, and generating electrical energy.In the 1830s, the British astronomer John Herschel used a solar collector box to cook food during an expedition to Africa.Now,people are trying to use the sun's energy for lots of things.Electric utilities are trying photovoltaics, a process by which solar energy is converted directly to electricity.Electricity can be produced directly from solar energy using photovoltaic devices or indirectly from steam generators using solar thermal collectors to heat a working fluid. Out of the 14 known solar electric generating units operating in the US at the end of 2004, 10 of these are in California, and 4 in Arizona. No statistics are being collected on solar plants that produce less than 1 megawatt of electricity, so there may be smaller solar plants in a number of other states. PHOTOVOLTAIC ENERGYPhotovoltaic energy is the conversion of sunlight into electricity through a photovoltaic (PVs) cell,commonly called a solar cell. A photovoltaic cell is a nonmechanical device usually made from silicon alloys.Sunlight is composed of photons, or particles of solar energy. These photons contain various amounts of energy corresponding to the different wavelengths of the solar spectrum. When photons strike a photovoltaic cell, they may be reflected, pass right through, or be absorbed. Only the absorbed photons provide energy to generate electricity.When enough sunlight (energy) is absorbed by the material (a semiconductor), electrons are dislodged from the material's atoms. Special treatment of the material surface during manufacturing makes the front surface of the cell more receptive to free electrons,so the electrons naturally migrate to the surface.When the electrons leave their position, holes are formed. When many electrons,each carrying a negative charge, travel toward the front surface of the cell, the resulting imbalance of charge between the cell's front and back surfaces creates a voltage potential like the negative and positive terminals of a battery.When the two surfaces are connected through an external load, electricity flows.The photovoltaic cell is the basic building block of a PV system. Individual cells can vary in size from about 1 cm (1/2 inch) to about 10 cm (4 inches) across.However, one cell only produces 1 or 2 watts, which isn't enough power for most applications.To increase power output, cells are electrically connected into a packaged weather-tight module. Modules can be further connected to form an array. The term array refers to the entire generating plant, whether it is made up of one or several thousand modules. As many modules as needed can be connected to form the array size(power output) needed.The performance of a photovoltaic array is dependent upon sunlight. Climate conditions (e.g., clouds, fog) have a significant effect on the amount of solar energy received by a PV array and, in turn, its performance. Most current technology photovoltaic modules are about 10 percent efficient in converting sunlight with further research being conducted to raise this efficiency to 20 percent.The pv cell was discovered in 1954 by Bell Telephone researchers examining the sensitivity of a properly prepared silicon wafer to sunlight. Beginning in the late 1950s, pvs were used to power U.S. space satellites.The success of PVs in space generated commercial applications for pv technology. The simplest photovoltaic systems power many of the small calculators and wrist watches used everyday. More complicated systems provide electricity to pump water, power communications equipment, and even provide electricity to our homes.Photovoltaic conversion is useful for several reasons. Conversion from sunlight to electricity is direct, so that bulky mechanical generator systems are unnecessary. The modular characteristic of photovoltaic energy allows arrays to be installed quickly and in any size required or allowed.Also, the environmental impact of a photovoltaic system is minimal, requiring no water for system cooling and generating no by-products. Photovoltaic cells,like batteries,generate direct current (DC) which is generally used for small loads (electronic equipment). When DC from photovoltaic cells is used for commercial applications or sold to electric utilities using the electric grid, it must be converted to alternating current (AC) using inverters,solid state devices that convert DC power to AC. Historically, pvs have been used at remote sites to provide electricity. However, a market for distributed generation from PVs may be developing with the unbundling of transmission and distribution costs due to electric deregulation. The siting of numerous small-scale generators in electric distribution feeders could improve the economics and reliability of the distribution system.SOLAR THERMAL HEATThe major applications of solar thermal energy at present are heating swimming pools, heating water for domestic use, and space heating of buildings. For these purposes, the general practice is to use flat-plate solar-energy collectors with a fixed orientation (position).Where space heating is the main consideration, the highest efficiency with a fixed flat-plate collector is obtained if it faces approximately south and slopes at an angle to the horizon equal to the latitude plus about 15 degrees. Solar collectors fall into two general categories: nonconcentrating and concentrating.In the nonconcentrating type, the collector area (i.e. the area that intercepts the solar radiation)is the same as the absorber area (i.e., the area absorbing the radiation).In concentrating collectors,the area intercepting the solar radiation is greater, sometimes hundreds of times greater, than the absorber area. Where temperatures below about 200o F are sufficient,such as for space heating,flat-plate collectors of the nonconcentrating type are generally used.There are many flat-plate collector designs but generally all consist of (1) a flat-plate absorber, which intercepts and absorbs the solar energy, (2) a transparent cover(s) that allows solar energy to pass through but reduces heat loss from the absorber, (3) a heat-transport fluid (air or water) flowing through tubes to remove heat from the absorber,and(4) a heat insulating backing.Solar space heating systems can be classified as passive or active.In passive heating systems, the air is circulated past a solar heat surface(s) and through the building by convection (i.e. less dense warm air tends to rise while more dense cooler air moves downward) without the use of mechanical equipment. In active heating systems, fans and pumps are used to circulate the air or the heat absorbing fluid.SOLAR THERMAL POWER PLANTSSolar thermal power plants use the sun's rays to heat a fluid, from which heat transfer systems may be used to produce steam. The steam, in turn, is converted into mechanical energy in a turbine and into electricity from a conventional generator coupled to the turbine.Solar thermal power generation is essentially the same as conventional technologies except that in conventional technologies the energy source is from the stored energy in fossil fuels released by combustion. Solar thermal technologies use concentrator systems due to the high temperatures needed for the working fluid.PARABOLIC TROUGHThe parabolic trough is used in the largest solar power facility in the world located in the Mojave Desert at Kramer Junction, California. This facility has operated since the 1980 and accounted for the majority of solar electricity produced by the electric power sector in2004.A parabolic trough collector has a linear parabolic-shaped reflector that focuses the sun's radiation on a linear receiver located at the focus of the parabola. The collector tracks the sun along one axis from east to west during the day to ensure that the sun is continuously focused on the receiver.Because of its parabolic shape, a trough can focus the sun at 30 to 100 times its normal intensity (concentration ratio) on a receiver pipe located along the focal line of the trough, achieving operating temperatures over400degrees Celcius.A collector field consists of a large field of single-axis tracking parabolic trough collectors. The solar field is modular in nature and is composed of many parallel rows of solar collectors aligned on a north-south horizontal axis. A working (heat transfer) fluid is heated as it circulates through the receivers and returns to a series of heat exchangers at a central location where the fluid is used to generate high-pressure superheated steam. The steam is then fed to a conventional steam turbine/generator to produce electricity.After the working fluid passes through the heat exchangers, the cooled fluid is recirculated through the solar field.The plant is usually designed to operate at full rated power using solar energy alone, given sufficient solar energy. However, all plants are hybrid solar/fossil plants that have a fossil-fired capability that can be used to supplement the solar output during periods of low solar energy. The Luz plant is a natural gas hybrid.SOLAR DISHA solar dish/engine system utilizes concentrating solar collectors that track the sun on two axes, concentrating the energy at the focal point of the dish because it is always pointed at the sun. The solar dish's concentration ratio is much higher that the solar trough, typically over 2,000,owith a working fluid temperature over 750 C. The power-generating equipment used with a solar dish can be mounted at the focal point of the dish, making it well suited for remote operations or, as with the solar trough, the energy may be collected from a number of installations and converted to electricity at a central point. The engine in a solar dish/engine system converts heat to mechanical power by compressing the working fluid when it is cold, heating the compressed working fluid, and then expanding the fluid through a turbine or with a piston to produce work. The engine is coupled to an electric generator to convert the mechanical power to electric power. SOLAR POWER TOWERA solar power tower or central receiver generates electricity from sunlight by focusing concentrated solar energy on a tower-mounted heat exchanger (receiver).This system uses hundreds to thousands of flat sun-tracking mirrors called heliostats to reflect and concentrate the sun's energy onto a central receiver tower. The energy can be concentrated as much as 1,500 times that of the energy coming in from the sun. Energy losses from thermal-energy transport areminimized as solar energy is being directly transferred by reflection from the heliostats to a single receiver,rather than being moved through a transfer medium to one central location,as with parabolic troughs. Power towers must be large to be economical. This is a promising technology for large-scale grid-connected power plants.Though power towers are in the early stages of development compared with parabolic trough technology, a number of test facilities have been constructed around the world.Last Revised:July 2008Sources: Energy Information Administration, Electric Power Annual, Form EIA-860, Annual Electric Generator Report database.来自太阳的能源太阳产生能量已有数十亿年，太阳能是太阳辐射到地球的能量。
外文翻译中英文
Wind turbine gearbox OverviewOverview:Wind turbine gearbox is an important mechanical components, and its main function is to wind round the momentum generated by wind is passed to the generator and make the appropriate speed. Usually wind wheel speed is very low, far less than required by the generator speed, the growth rate effect of the gearbox gear vice, so the gearbox will also be called a growth box. According to the general layout of the unit, sometimes the wind turbine wheel is directly connected to the drive shaft (commonly known as the shaft) and the gear box together as one, shaft and gearbox are arranged, during which the tension device or coupling connected structure. Brakes in order to increase the braking capacity of the unit, often set in the input or output of the gearbox, with the tip brake (fixed pitch wind wheel) or pitch from the brake to the unit drive system combined braking.Unit installed in the mountains, wilderness, beaches, islands and other outlet by the impact of erratic change to the variable load wind and strong gusts of perennial withstand extreme temperatures and extreme temperature variations, combined with the natural environment in which the traffic inconvenience, The gear box is installed in the narrow space within the tower, once the failure, repair is very difficult, so its reliability and service life are much higher than the average mechanical demands. For example, the requirements of the component materials, in addition to the normal state of the mechanical properties, but also should have the characteristics of low temperature resistance to cold brittleness; should ensure the smooth work of the gear box to prevent vibration and shock; to ensure adequate lubrication conditions, and so on. Huge temperature difference between summer and winter areas, to configure the appropriateheating and cooling devices. Also set up monitoring points remote operation and lubrication state.Different forms of wind turbines are not the same requirements, the arrangement of form and structure of the gearbox and therefore vary. The horizontal axis wind turbine in the wind power sector is the most common fixed parallel shaft gear drive and the planetary gear drive.As mentioned earlier, the wind power generation by natural conditions, the emergence of some special meteorological conditions, all of which might lead to the failure of wind turbine not like small cabin on the ground as a solid base foundation of the entire powertrain power matching and torsional vibration factor is always concentrated reflection of a weak link, and a lot of practice, this link is often the gearbox in unit. Therefore, the strengthening of the gearbox, the great importance of its maintenance work is particularly important.The design requirementsThe design must guarantee to meet the reliability and life expectancy under the premise, to simplify the structure and the lightest. Normally be by CAD design, schedule the best transmission scheme, the choice of design parameters, select reliable components and has good mechanical properties as well as in the environmental extreme temperature remains stable material, and so on.First, the design loadGearbox as components of the transmission of power during operation at the same time withstand the dynamic and static load. Dynamic load part depends on the wind wheel, the characteristics and the shaft of the generator, the quality of the coupling stiffness and damping values, as well as the generator of external working conditions. Load spectrum of the wind turbine gearbox design calculation on the basis of the load spectrum by the measured, calculated and determined in accordance withthe standards of the JB/T10300.When the spectrum calculated in accordance with the measured load, the gear box using the coefficient of the KA = 1. When can not get the load spectrum, take the KA = 1.3 for three-bladed wind turbine.Second, the design requirementsGrowth of wind turbine design parameters of the box, except as otherwise provided, is often used to optimize the design, namely the use of computer analysis and calculation, to obtain the optimal design program to meet the constraints.(A) EfficiencyThe efficiency of the gearbox power loss calculation or get measured in the experiment. The power loss including the gear meshing, bearing friction, lubricant splashing and mixing losses, windage loss, and other mechanical damping. The efficiency of the gear under different conditions is inconsistent.Wind turbine gearbox professional standards require that the mechanical efficiency of the gear box should be greater than 97%, refers to the indicators to be achieved under standard conditions.(B) noise levelNoise standards for wind power growth rate box for around 85dB (A). The noise from the various transmission parts, it should take the appropriate measures to reduce noise:1.appropriate increase in the precision gears, tooth repair edge to increase the engagement degree of coincidence;2 .increase the stiffness of the shaft and bearing;3.rational arrangement of the shaft and the transmission gear train, to avoid resonance;4. Installation to take the necessary damping mechanical vibration of the gearbox control GB/T8543 the provisions of the C(C) ReliabilityIn accordance with the requirements of the assumed life expectancy of at least 20 years, depending on the load spectrum listed in the load distribution of the fatigue analysis, limit state of the whole and parts of the gear box design and the use of limit state, ultimate strength analysis, fatigue analysis, stability, and deformation limits analysis, dynamic analysis. Analysis methods can be simulated host operating conditions in addition to the usual recommended design calculation method of component testing.The reliability analysis must be carried out in the beginning of the program design, and again after the completion of the construction design of a detailed reliability analysis of computing, including carefully selected good reliability structures and the reliability of estimates of important spare parts and machine.Gear boxMany different types of wind turbine gearbox in accordance with the conventional type can be divided into the growth of cylindrical gear boxes, planetary growth box, gear box as well as their combination with each other up; in accordance with the transmission of the series can be divided into single and multi-stage gear box; in accordance with the rotation of the arrangement can be divided into the expansion, diversion, and coaxial-type and mixed type and so on.HeaderThe cabinet is made of the important parts of the gearbox, which bear the reaction force generated from the force of the wind wheel and gear drive, you must have sufficient rigidity to withstand the forces and moments to prevent the deformation, to ensure the transmission quality. The cabinet design should be arranged in accordance with the layout of the wind turbine power transmission, processing and assembly conditions,to facilitate inspection and maintenance requirements to carry out. Should pay attention to the different directions of the bearing support and the base supporting the anti-force and its relative value, select the appropriate support structure and wall thickness, and the addition of the necessary ribs. The location of the tendons shall be consistent with the direction of cabinet deformation caused by force.Box stress situation is very complex and uneven distribution, only the use of modern calculation methods, such as finite element and fracture mechanics methods supplemented by photoelastic experiment simulates actual working conditions, in order to more accurately calculate the stress distribution situation. Using computer-aided design, can be obtained with the actual stress is very close to the results. Gearbox lubricationLubrication of the gear box is very important, good lubrication can serve as adequate protection for gears and bearings. Therefore, we must attach great importance to the lubrication of the gear box, and long-term in the best condition in strict accordance with specifications to maintain lubrication system. The gear box is often used splash lubrication or forced lubrication is more common, usually with forced lubrication.Therefore, with a reliable lubrication system is particularly important. Will be electric gear pump oil from the tank by the oil filter transmitted to the gear box lubrication piping, lubricating the various parts of the gear and transmission pipeline is equipped with a variety of monitoring devices to ensure that the gearbox in operation which does not appear off the oil.Lubricating oil requirements should be considered:1)reduce the friction and wear, with a high carrying capacity, to prevent the glue; 2)to absorb shock and vibration; 3) to prevent fatigue pitting; 4) cooling, rust, corrosion-resistant. Transmission of different types have differentrequirements. Wind turbine gearbox is a type of enclosed gear drives, the main form of failure is glued pitting Therefore, the choice of lubricant, the focus is to ensure adequate oil film thickness and the boundary film strength. Work in a larger temperature difference, the viscosity index is relatively high. To improve the carrying capacity and impact resistance of the gear appropriate to add some extreme pressure additives is also necessary to have some side effects, but the additives must be careful in the choice of when. The gearbox manufacturer generally recommend a variety of lubricants according to their experience or experimental studies, such as MOBIL632,MOBIL630 or L-CKC320 L-CKC220GB5903-95 gear oil is selected according to the tooth surface contact stress and the use of environmental conditions.Gear damageGear damage the impact of many factors, including material selection, design calculations, processing, heat treatment, installation and commissioning, lubrication and maintenance. Common damage of the gear tooth surface damage and tooth broken two.(A) of the tooth fracture (broken teeth)断齿常由细微裂纹逐步扩展而成。
外文翻译—电力电子技术（英文+译文）
1 Power Electronic ConceptsPower electronics is a rapidly developing technology. Components are tting higher current and voltage ratings, the power losses decrease and the devices become more reliable. The devices are also very easy tocontrol with a mega scale power amplification. The prices are still going down pr. kVA and power converters are becoming attractive as a mean to improve the performance of a wind turbine. This chapter will discuss the standard power converter topologies from the simplest converters for starting up the turbine to advanced power converter topologies, where the whole power is flowing through the converter. Further, different park solutions using power electronics arealso discussed.1.1 Criteria for concept evaluationThe most common topologies are selected and discussed in respect to advantages and drawbacks. Very advanced power converters, where many extra devices are necessary in order to get a proper operation, are omitted.1.2 Power convertersMany different power converters can be used in wind turbine applications. In the case of using an induction generator, the power converter has to convert from a fixed voltage and frequency to a variable voltage and frequency. This may be implemented in many different ways, as it will be seen in the next section. Other generator types can demand other complex protection. However, the most used topology so far is a soft-starter, which is used during start up in order to limit the in-rush current and thereby reduce the disturbances to the grid.1.2.1 Soft starterThe soft starter is a power converter, which has been introduced to fixedspeed wind turbines to reduce the transient current during connection or disconnection of the generator to the grid. When the generator speed exceeds the synchronous speed, the soft-starter is connected. Using firing angle control of the thyristors in the soft starter the generator is smoothly connected to the grid over a predefined number of grid periods. An example of connection diagram for the softstarter with a generator is presented in Figure1.Figure 1. Connection diagram of soft starter with generators.The commutating devices are two thyristors for each phase. These are connected in anti-parallel. The relationship between the firing angle (﹤) and the resulting amplification of the soft starter is non-linear and depends additionally on the power factor of the connected element. In the case of a resistive load, may vary between 0 (full on) and 90 (full off) degrees, in the case of a purely inductive load between 90 (full on) and 180 (full off) degrees. For any power factor between 0 and 90 degrees, w ill be somewhere between the limits sketched in Figure 2.Figure 2. Control characteristic for a fully controlled soft starter.When the generator is completely connected to the grid a contactor (Kbyp) bypass the soft-starter in order to reduce the losses during normal operation. The soft-starter is very cheap and it is a standard converter in many wind turbines.1.2.2 Capacitor bankFor the power factor compensation of the reactive power in the generator, AC capacitor banks are used, as shown in Figure 3. The generators are normally compensated into whole power range. The switching of capacitors is done as a function of the average value of measured reactive power during a certain period.Figure 3. Capacitor bank configuration for power factor compensation ina wind turbine.The capacitor banks are usually mounted in the bottom of the tower or in thenacelle. In order to reduce the current at connection/disconnection of capacitors a coil (L) can be connected in series. The capacitors may be heavy loaded and damaged in the case of over-voltages to the grid and thereby they may increase the maintenance cost.1.2.3 Diode rectifierThe diode rectifier is the most common used topology in power electronic applications. For a three-phase system it consists of six diodes. It is shown in Figure 4.Figure 4. Diode rectifier for three-phase ac/dc conversionThe diode rectifier can only be used in one quadrant, it is simple and it is notpossible to control it. It could be used in some applications with a dc-bus.1.2.4 The back-to-back PWM-VSIThe back-to-back PWM-VSI is a bi-directional power converter consisting of two conventional PWM-VSI. The topology is shown in Figure 5.To achieve full control of the grid current, the DC-link voltage must be boosted to a level higher than the amplitude of the grid line-line voltage. The power flow of the grid side converter is controlled in orderto keep the DC-link voltage constant, while the control of the generator side is set to suit the magnetization demand and the reference speed. The control of the back-to-back PWM-VSI in the wind turbine application is described in several papers (Bogalecka, 1993), (Knowles-Spittle et al., 1998), (Pena et al., 1996), (Yifan & Longya, 1992), (Yifan & Longya, 1995).Figure 5. The back-to-back PWM-VSI converter topology.1.2.4.1 Advantages related to the use of the back-to-back PWM-VSIThe PWM-VSI is the most frequently used three-phase frequency converter. As a consequence of this, the knowledge available in the field is extensive and well established. The literature and the available documentation exceed that for any of the other converters considered in this survey. Furthermore, many manufacturers produce components especially designed for use in this type of converter (e.g., a transistor-pack comprising six bridge coupled transistors and anti paralleled diodes). Due to this, the component costs can be low compared to converters requiring components designed for a niche production.A technical advantage of the PWM-VSI is the capacitor decoupling between the grid inverter and the generator inverter. Besides affording some protection, this decoupling offers separate control of the two inverters, allowing compensation of asymmetry both on the generator side and on the grid side, independently.The inclusion of a boost inductance in the DC-link circuit increases the component count, but a positive effect is that the boost inductance reduces the demands on the performance of the grid side harmonic filter, and offers some protection of the converter against abnormal conditions on the grid.1.2.4.2 Disadvantages of applying the back-to-back PWM-VSIThis section highlights some of the reported disadvantages of the back-to-back PWM-VSI which justify the search for a more suitable alternative converter:In several papers concerning adjustable speed drives, the presence of the DC link capacitor is mentioned as a drawback, since it is heavy and bulky, it increases the costs and maybe of most importance, - it reduces the overall lifetime of the system. (Wen-Song & Ying-Yu, 1998); (Kim & Sul, 1993); (Siyoung Kim et al., 1998).Another important drawback of the back-to-back PWM-VSI is the switching losses. Every commutation in both the grid inverter and the generator inverter between the upper and lower DC-link branch is associated with a hard switching and a natural commutation. Since the back-to-back PWM-VSI consists of two inverters, the switching losses might be even more pronounced. The high switching speed to the grid may also require extra EMI-filters.To prevent high stresses on the generator insulation and to avoid bearing current problems (Salo & Tuusa, 1999), the voltage gradient may have to be limited by applying an output filter.1.2.5 Tandem converterThe tandem converter is quite a new topology and a few papers only have treated it up till now ((Marques & Verdelho, 1998); (Trzynadlowski et al., 1998a); (Trzynadlowski et al., 1998b)). However, the idea behind the converter is similar to those presented in ((Zhang et al., 1998b)), where the PWM-VSI is used as an active harmonic filter to compensate harmonic distortion. The topology of the tandem converter is shown inFigure 6.Figure 6. The tandem converter topology used in an induction generator wind turbine system.The tandem converter consists of a current source converter, CSC, in thefollowing designated the primary converter, and a back-to-back PWM-VSI, designated the secondary converter. Since the tandem converter consists of four controllable inverters, several degrees of freedom exist which enable sinusoidal input and sinusoidal output currents. However, in this context it is believed that the most advantageous control of the inverters is to control the primary converter to operate in square-wave current mode. Here, the switches in the CSC are turned on and off only once per fundamental period of the input- and output current respectively. In square wave current mode, the switches in the primary converter may either be GTO.s, or a series connection of an IGBT and a diode.Unlike the primary converter, the secondary converter has to operateat a high switching frequency, but the switched current is only a small fraction of the total load current. Figure 7 illustrates the current waveform for the primary converter, the secondary converter, is, and the total load current il.In order to achieve full control of the current to/from the back-to-back PWMVSI, the DC-link voltage is boosted to a level above the grid voltage. As mentioned, the control of the tandem converter is treated in only a few papers. However, the independent control of the CSC and the back-to-back PWM-VSI are both well established, (Mutschler & Meinhardt, 1998); (Nikolic & Jeftenic, 1998); (Salo & Tuusa, 1997); (Salo & Tuusa, 1999).Figure 7. Current waveform for the primary converter, ip, the secondary converter, is, and the total load current il.1.2.5.1Advantages in the use of the Tandem ConverterThe investigation of new converter topologies is commonly justifiedby thesearch for higher converter efficiency. Advantages of the tandem converter are the low switching frequency of the primary converter, and the low level of the switched current in the secondary converter. It is stated that the switching losses of a tandem inverter may be reduced by 70%, (Trzynadlowski et al., 1998a) in comparison with those of an equivalent VSI, and even though the conduction losses are higher for the tandem converter, the overall converter efficiency may be increased.Compared to the CSI, the voltage across the terminals of the tandem converter contains no voltage spikes since the DC-link capacitor of the secondary converter is always connected between each pair of input- and output lines (Trzynadlowski et al., 1998b).Concerning the dynamic properties, (Trzynadlowski et al., 1998a) states that the overall performance of the tandem converter is superior to both the CSC and the VSI. This is because current magnitude commands are handled by the voltage source converter, while phase-shift current commands are handled by the current source converter (Zhang et al., 1998b).Besides the main function, which is to compensate the current distortion introduced by the primary converter, the secondary converter may also act like an active resistor, providing damping of the primary inverter in light load conditions (Zhang et al., 1998b).1.2.5.2 Disadvantages of using the Tandem ConverterAn inherent obstacle to applying the tandem converter is the high number of components and sensors required. This increases the costs and complexity of both hardware and software. The complexity is justified by the redundancy of the system (Trzynadlowski et al., 1998a), however the system is only truly redundant if a reduction in power capability and performance is acceptable.Since the voltage across the generator terminals is set by the secondary inverter, the voltage stresses at the converter are high.Therefore the demands on the output filter are comparable to those when applying the back-to-back PWM-VSI.In the system shown in Figure 38, a problem for the tandem converter in comparison with the back-to-back PWM-VSI is the reduced generator voltage. By applying the CSI as the primary converter, only 0.866% of the grid voltage can be utilized. This means that the generator currents (and also the current through the switches) for the tandem converter must be higher in order to achieve the same power.1.2.6 Matrix converterIdeally, the matrix converter should be an all silicon solution with no passive components in the power circuit. The ideal conventional matrix converter topology is shown in Figure 8.Figure 8. The conventional matrix converter topology.The basic idea of the matrix converter is that a desired input current (to/from the supply), a desired output voltage and a desired output frequency may be obtained by properly connecting the output terminals of the converter to the input terminals of the converter. In order to protect the converter, the following two control rules must be complied with: Two (or three) switches in an output leg are never allowed to be on at the same time. All of the three output phases must be connected to an input phase at any instant of time. The actual combination of the switchesdepends on the modulation strategy.1.2.6.1 Advantages of using the Matrix ConverterThis section summarises some of the advantages of using the matrix converter in the control of an induction wind turbine generator. For a low output frequency of the converter the thermal stresses of the semiconductors in a conventional inverter are higher than those in a matrix converter. This arises from the fact that the semiconductors in a matrix converter are equally stressed, at least during every period of the grid voltage, while the period for the conventional inverter equals the output frequency. This reduces thethermal design problems for the matrix converter.Although the matrix converter includes six additional power switches compared to the back-to-back PWM-VSI, the absence of the DC-link capacitor may increase the efficiency and the lifetime for the converter (Schuster, 1998). Depending on the realization of the bi-directional switches, the switching losses of the matrix inverter may be less than those of the PWM-VSI, because the half of the switchings become natural commutations (soft switchings) (Wheeler & Grant, 1993).1.2.6.2 Disadvantages and problems of the matrix converterA disadvantage of the matrix converter is the intrinsic limitation of the output voltage. Without entering the over-modulation range, the maximum output voltage of the matrix converter is 0.866 times the input voltage. To achieve the same output power as the back-to-back PWM-VSI, the output current of the matrix converter has to be 1.15 times higher, giving rise to higher conducting losses in the converter (Wheeler & Grant, 1993).In many of the papers concerning the matrix converter, the unavailability of a true bi-directional switch is mentioned as one of the major obstacles for the propagation of the matrix converter. In the literature, three proposals for realizing a bi-directional switch exists. The diode embedded switch (Neft & Schauder, 1988) which acts like a truebi-directional switch, the common emitter switch and the common collector switch (Beasant et al., 1989).Since real switches do not have infinitesimal switching times (which is not desirable either) the commutation between two input phases constitutes a contradiction between the two basic control rules of the matrix converter. In the literature at least six different commutation strategies are reported, (Beasant et al., 1990); (Burany, 1989); (Jung & Gyu, 1991); (Hey et al., 1995); (Kwon et al., 1998); (Neft & Schauder, 1988). The most simple of the commutation strategies are those reported in (Beasant et al., 1990) and (Neft & Schauder, 1988), but neither of these strategies complies with the basic control rules.译文1 电力电子技术的内容电力电子技术是一门正在快速发展的技术,电力电子元器件有很高的额定电流和额定电压,它的功率减小元件变得更加可靠、耐用.这种元件还可以用来控制比它功率大很多倍的元件。
道路路桥工程中英文对照外文翻译文献
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外文翻译英文
Utilization of urban sewage sludge: Chinese perspectives Purpose Urbanization and industrialization in China has resulted in a dramatic increase in the volume of wastewater and sewage sludge produced from wastewater treatment plants. Problems associated with sewage sludge have attracted increasing attention from the public and urban planners. How to manage sludge in an economically and environmentally acceptable manner is one of the critical issues that modern societies are facing.Methods Sludge treatment systems consist of thickening, dewatering，and several different alternative main treatments(anaerobic digestion, aerobic digestion, drying, composting, and incineration). Agricultural application, landfill, and incineration are the principal disposal methods for sewage sludge in China. However, sewage sludge disposal in the future should focus on resource recovery, reducing environmental impacts and saving economic costs.Results The reuse of biosolids in all scenarios can be environmentally beneficial and cost-effective. Anaerobic digestion followed by land application is the preferable options due to low economic and energy costs and material reuse.Conclusion It is necessary to formulate a standard suitable for the utilization of sewage sludge in China.1 IntroductionIn 2008, it is estimated that 57 billion tons of municipal wastewater was discharged in China, 58% of which came from municipal domestic sewage, while the production of municipal wastewater and dewatered sewage in China increased approximately 5% per year on average from 1998 to 2009 as shown in Fig.1.Sewage sludge as an inevitable by-product of wastewater treatment process presents a number of environmental concerns.Wastewater treatment processes concentrate various pollutants such as heavy metals, organic micro-pollutants, and pathogens into sludge. Sludge disposal can thereby result in the release of toxins into the environment and subsequently into the food chain. On the other hand, it has been estimated that depending on technology choice, approximately 30∼60% of sewage treatment plant operating costs are related to sludge treatment activities. Therefore, the management of sewage sludge in an economically and environmentally acceptable way is a matter of increasing importance.Fig. 1 Production of municipal wastewater and dewatered sewage sludge in ChinaAn ideal way to solve the issue of sludge waste is to minimize its production in biological wastewater treatment processes, rather than rely on post-treatment. When mechanical wastewater treatment is used, a diversity of approaches for sewage sludge treatment processes and end use exists, each with different associated costs and environmental impacts. Strategies on end uses of biosolids have traditionally been based on cost, regulatory, environmental, and public acceptance considerations. In recent years, several methods have been used to evaluate their economic and environmental acceptability. Hospido et al considered land application as an acceptable option for anaerobic digested sludge by evaluating environmental and economic costs of threescenarios (land application, incineration, and pyrolysis of dried sludge), but the environmental impact of construction was ignored. Also little detailed economic analysis information is available for other alternative scenarios. Barber used a model comparing the environmental impacts and economic costs of different alternative treatment and disposal scenarios. Nevertheless, the transport costs associated with the full range of biosolids management options were not discussed, which may be one of the limiting factors of sludge land application in China. Few investigations have been reported on the environmental and economic impacts of pyrolysis and gasification scenario, partly due to their high cost and scarce application in practice. Therefore, more detailed papers should be investigated for an overall comparison of different treatment and end use of urban sewage sludge, to determine which combinations are more sustainable.There are 1,258 municipal wastewater treatment plants(WWTPs) in China. The method of sewage sludge disposal is carried out using four processes: 45% of the sludge produced is being utilized in agriculture, 3.5% is being incinerated, 34.5% is landfilled including 3.5% with domestic waste, while 3.5% is used in some other areas (Fig. 2). There are political and economic incentives to increase the agriculture application of sludge since it contains large amounts of organic matter and nutrients, such as N and P. However, the reduced availability of land, increased public comprehension of pathogen risk, the potential for food chain contamination by heavy metals, and the risk of uncertainty surrounding organic micropollutants act to limit sludge land application. Landfill is also decreasing because of technology, economic capacity, and new legislation. Incineration due to significant dry solid volume reduction and energy recovery from the sludge can contribute to a sustainable biosolids strategy, but environmental pollution and the cost should becarefully treated. Other disposal options such as pyrolysis, gasification,combustion,and co-combustion of sewage sludge with other materials and use as an energy source in the production of cement or building materials have been intensively investigated. These processes which can recover energy from sewage sludge will probably become the future trends of development.Fig. 2 Ways of sludge disposal and utilization in China (2010)Based on the above considerations, it can be expected that studies for the treatment of sewage sludge shall focus on the following aspects: safe handling, resource recovery, and low economic costs. In all these respects, the recovery of sustainable energy from sewage sludge will be of obvious importance. Another issue of concern is to reduce toxins in sewage sludge before the final treatment and minimize the negative impacts on human and ecosystem health. The aim of this paper is to discuss the current situation and future outlook for sewage sludge treatment and disposal and estimate the environmental and economic impacts of various options from sewage sludge. It also provides some reference for decision makers to better manage sewage sludge.2 Composition of sewage sludge in ChinaThe composition and characteristics of sewage sludge depend on several factors, such as the origin of the wastewater, the purification treatment of the wastewater, stabilization treatment, time and storage conditions, or the coagulant agents used. Generally, sewage sludge is composed of organic compounds, macronutrients, and a wide range of micronutrients, non-essential trace metals, organic micropollutants, and microorganisms. It should be stated that some parameters are important when considering the ultimate disposal of the processed sludge and energy reuse from the sludge during treatment. Dry matter has an effect on fuel requirements, exhaust gas production at the incineration process, and the cost of sludge transportation. V olatile matter, a measure of the sludge organic content, is the most important parameter regarding the energetic use of sewage sludge. Other factors, such as harmful organic compounds, micropollutants, nutrients, and heavy metal, cannot be neglected. According to Hua et al., polynuclear aromatic hydrocarbons have become one of the primary pollutants in sludge of Zhejiang WWTPs instead of heavy metals, which has a great influence on agriculture application of sewage sludge. Emerging contaminants such as pharmaceuticals, personal care products, illicit drugs, flame retardants, and perfluorinated compounds should be focused on, due to their endocrine-disrupting properties. N and P are essential resources especially with respect to P. Natural P deposits of sufficient quality are becoming scare, prompting rapid price increase. As a result, large quantities of sludge are applied to farmland. Heavy metal content which is very sensitive to the wastewater source decides whether sewage sludge can be applied to land or not. The threshold value of heavy metal for sludge end use should meet the Pollutants Control Standard of Sludge.3 Sewage sludge treatment process and anaerobic digestionSludge treatment process Biosolids management was divided into categories for sludge treatment and end use, which are likely to be realized by different entities—the wastewater treatment plant and the recipient of treated sludge. Sludge treatment systems generally consist of thickening, dewatering, and several alternative main treatments, such as anaerobic digestion, aerobic digestion, drying, composting, and incineration, which are critical in determining biosolids quality and post-treatment options. Anaerobic digestion or composting is used to meet regulatory requirement for pathogen and remnant organic materials reduction prior to land application. Although incineration can significantly decrease dry solid volume and effectively attain a 100% reduction of pathogens and viruses, it produces dioxins, furans, and fly ash, as incurring as higher running/operational costs. Drying is a necessary process prior to thermal utilization of sewage sludge. The moisture content should meet standards regulated by Chinese legislation after sludge treatment.Life cycle assessment as an environmental information analysis tool to aid planners in the wastewater treatment plant has been extensively applied to sludge treatment. Hong et al carried out a quantified environmental and economic analysis of six alternative scenarios: dewatering, dewatered sludge composting, dewatered sludge drying, dewatered sludge incineration, incinerated ash melting, and dewatered sludge melting, each with and without digestion. The results show that sewage sludge digestion leads to the lower economic and environmental impacts, while dewatered sludge melting is an environmentally optimal and economically affordable method. Murry et al. did an integrated study, comparing nine alternative treatment schemes and arranged them in order of environmental and economic impacts. They proposed that anaerobic digestion (no lime) is overall the most preferable sludge treatment option whereas incineration, particularly coal-fired, is the most costly. Acommon feature of these methods was the utilization of the resource embodied in sludge; for example, heat drying with compost takes advantage of embodied nutrients, anaerobic digestion, and incineration of sewage sludge takes advantage of embodied energy. Overall, in order to decrease the environmental and economic impacts during sludge treatment, maximizing potential offsets, including the efficiency of the thickening process, energy capture from anaerobic digestion, and the electricity production rate generated from biogas, is required.Anaerobic digestion Anaerobic digestion is considered an essential process in a modern WWTP due to reduction of sludge volume, generation of energy-rich biogas, and production of a nutrient-rich final product. Compared with other technologies, it is the most efficient method to capture energy from biosolids with high water content. Barber reported that the conversion of methane produced from anaerobic digestion to electricity and heat is the main contributor to renewable energy within the WWTP. In the EU, 50% of sewage treatment plants have anaerobic digestion, 18% incorporate aerobic digestion, and 4% lime stabilization, whereas 24% of the plants undertake no sludge stabilization. The same tendency is observed in China, but no detailed available information was reported. However, its application has often been limited by very long retention times and low overall degradation efficiency. In order to increase biodegradability and enhance anaerobic digestion with lower retention time and higher biogas production, various sludge pretreatment techniques have been applied in sludge digestion. These processes include biological (largely thermal phased anaerobic), thermal hydrolysis, mechanical (such as ultrasound, high pressure and lysis), chemical with oxidation (mainly ozonation), alkali, and combined pretreatment.Currently, combined sludge digestion with other processes to achieve maximum utilization has attracted more and more attention. Using energy released by microbial decomposition to complete water evaporation in the process of biological drying is a promising method for dewatering sludge. There are some advantages in this process such as low-cost and energy consumption since no fossil fuel is depleted in such systems. Moreover, CO2 emission can also be significantly reduced, while the remaining sludge can be converted into amino acid salt with a content of 90% amino acid after acidification. An effective project like this has already been applied in Qinhuangdao City, China.4 Ways of sludge disposal and utilization4.1 Main disposal methods in ChinaLandfill Landfill is economical and low energy consumption due to its low-technology processes. However, it is a significant source of CH4and N2O, which are greenhouse gases with a high global warming potential. Leachate containing P and heavy metal can threaten surface and ground waters, and none of the nutrient or energy content is recovered from landfill. Biosolid management technologies for very small towns, with limited technical and financial resources, may justifiably consider investing in biofiltration or methane trapping and flaring at their local landfill.Land application Land application of sewage sludge has a great incentive in view of its fertility and soil conditioning properties. It has been shown that the use of sewage sludge derived soil amendments can improve soil physical properties, such as porosity, aggregate stability, bulk density, water retention and movement, and sequester carbon in the soil, thereby reducing atmospheric CO2content and global warming potential. The environmental offset in electricity and fuel consumption is also great when sludge is usedin place of synthetic fertilizers.Land application of sewage sludge is convenient and low requirements. Various stabilized biosolids such as slurry, dewatered cake, and dried pellets can be applied to land. However, sludge utilization can be limited due to its heavy metal, organic micropollutants, and pathogen content. Heavy metal concentrations depending on the relative contributor of industrial wastewaters to the overall flow can be decreased from sludge via source control. Pathogens are removed by pretreatment such as thermophilic anaerobic digestion, or composting.Land application is available only when the sludge quality meets the local criteria with respect to pathogens and heavy metal content. In addition, the doses and rates of sludge application should also be carefully considered. Reports show that excessive application of sludge has increased the bioavailability of heavy metals, which might pose a serious risk to human health. While long-term application of sewage sludge can result in leaching of P and heavy metals, the risks of which are greater than the transfer of heavy metals into plant tissue and the food chain in the case of crops.In addition, recovery of N and P should also be taken seriously. It is generally accepted that with the rapid urbanization in China, increasing amounts of N and P are entering the cities through food consumption. It is estimated that N and P contained in urban sewage sludge were 31,500 and 23,600 tons, respectively, in 2009. With increasing urbanization, the improvement of sewage treatment systems and nutrient use efficiency in food production systems, it is anticipated that nutrients contained in the urban waste stream are likely to increase dramatically in China in the next 10–20 years. Although the absolute amounts of N and P in sewage sludge are not great as compared to chemical fertilizersapplied to agricultural land in China, their emission to the environment will have serious impacts on water quality and ecosystem health. P, as a nonrenewable resource, is becoming depleted, and production of P fertilizer is increasingly more expensive, thus threatening food security globally. Therefore, recovery of nutrients from sewage sludge in a sustainable way is becoming an important challenge for environmental engineers.4.2 Thermochemical processes for sludgeIncineration Incineration of sewage sludge is a process in which its organic matter is completely transformed into CO2 and H2O under high-temperature and aerobic conditions, while inorganic compounds remain in the ash. It is an effective way to dispose of sludge with advantages such as large reduction of sludge volume, thermal destruction of toxic organic compounds, and minimization of odor generation. The final sludge volume after incineration is approximately 10% of that after mechanical dewatering. The energy produced in the incineration process can be used for drying the mechanically dewatered sludge cake prior to the incineration process or can be used for the production of electricity. The amount of energy produced strongly depends upon the water content of the sludge and performance of the incineration.Incineration as an attractive disposal method has been applied worldwide. For example, the amount of sludge being incinerated in Denmark has already reached 24% of the sludge produced, 20% in France, 15% in Belgium, and 14% in Germany, while in USA and Japan the percentage has increased to 25% and 55%, respectively. The main problems for combustion of sludge are high running cost and environmental impacts. Environmental problems relate to the accumulation of heavy metals in ashes and exhaust gases to the atmosphere. The former can be solved by using incineration ash as raw materials in cementmanufacturing, during which process heavy metals are immobilized in cement. Exhaust gases consist of dioxins, furans, and other pollutants (CO2, NO x, N2O, and SO x). Emissions of dioxins and furans are not generally a problem if temperatures above 600°C are kept and flue gases are rapidly cooled below 400°C. N2O can effectively be eliminated by increasing the combustion temperature to 880°C. Addition facilities such as electrostatic precipitators, wet scrubber system, etc. are also needed to comply with the strict exhaust gas emission standards. Large investment for the purification of flue gases may raise social objections.Co-combustion of sewage sludge with other natural resources (coal, lignite, or wood) or municipal solid waste is also an alternative method for the management of sewage sludge. Environmentally and economically, technology scenarios for co-combusting of biosolids meet Waste Incineration Directive emission criteria and provide a net energy gain, but absence of policy and legal clarity, supply chain insecurity, and market immaturity hinder the development of co-combustion.Incineration is suitable for cities; for example, Hangzhou has switched to incineration as the preferred option in sewage management, where land is very valuable. To avoid the high operation cost for sludge incineration and also to improve the energy recovery efficiency, exploiting new types of sewage sludge incinerators, implementation of a combined heat and power production unit at incineration plants, and the use of the polluted drying gas in the incineration process are feasible. It is expected that incineration will play an increasingly important role in sewage management in China in the coming decade. Pyrolysis Pyrolysis is a thermal decomposition of organic substances in the absence of air or in an oxygen-deficient atmosphere. The products of pyrolysis are biogas (noncondensable), bio-oil (condensable volatiles), and carbonaceous bio-char residue all of which have a potential end use and can be maximized by modulating the process conditions. Compared to incineration, pyrolysis has some potential advantages. One advantage is that the conversion of the combustible gases into electrical power can be achieved more efficiently.In addition, the formation and emission of toxic organic compounds, such as dioxins, NO x, and SO x, can be avoided in pyrolysis with low oxygen concentration.Using steam pyrolysis to treat sludge is currently a practice being conducted in China, for example, in the city of Shenzhen. After treatment, the moisture content of sludge is reduced from 80% to 50%, resulting in the final sludge volume decreasing by 60%. During this process, pathogen and odor can be thoroughly removed. The treatment sludge can be made into organic fertilizer, which can be used for horticulture and forestry cultivation. It is a proof of concept for the sustainable development of the circular economy.Other technologies, such as production of bio-oil from the pyrolysis of sewage sludge, have attracted attention due to the non-renewable nature and the increasing price of fossil fuel. Because the mechanism of such a process is complex, many parameters such as temperature, sewage sludge types, retention time, and the catalysts used affect bio-oil production. Literature concerning the production of bio-oil from sludge has demonstrated that the temperature and volatile solid content were the primary factors affecting oil and char yields. The maximum oil yield was achieved with primary sludge at 500°C, and the optimum pyrolysis temperature for waste activated sludge was 400°C. It is also stated that the optimal pyrolysis temperature for bio-oil production is 450°C. Experimental studies on pyrolysis liquids obtained from different sewage sludge have come to very interestingconclusions: High sewage sludge ash content favored the decrease in the char yield and the generation of nonvolatile gases, while the sewage sludge with less content of oxygen-containing compounds would favor the quality of the pyrolysis liquids. It elucidates some recommendable characteristics in order to use sewage sludge as pyrolysis feedstock. Metal oxide catalysts can have different influence on pyrolysis. The presence of Fe2O3 and ZnO probably inhibited the decomposition of organic matters in demineralized sludge samples to generate more solid residues, while Al2O3,CaO,and TiO2 promoted the degradation of organic matters to produce less solid residues. Al2O3 and TiO2 may decrease pyrolysis time, while CaO, Fe2O3, and ZnO may prolong pyrolysis time. It is therefore important to formulate optimal catalysts for such systems.However, the acceptance of this technology may be limited by the low economic value of the product, as well as the relative complexity of the processing equipments. The economic viability of pyrolysis may be improved if the yield of oil were enhanced or if value-added products such as adsorbents could be produced from the pyrolysis chars.5 PerspectivesThis paper reviews present and future directions of sewage sludge management in China. Up until now, most of the sewage sludge produced in the process of wastewater treatment has been used in agriculture or disposed of in landfills, or via incineration. Sewage sludge is rich in resources including nutrients and energy. Given the vast population and rapid urbanization in China, sewage sludge represents a major issue in environment and resource management. To resolve this issue, we propose that a holistic approach should be taken to manage sewage sludge in China, and future research and commercialization should focus on the following aspects:• Life-cycle analysis of food and water consumption in urbanized regions to provide a full account of nutrient flow within urban ecosystems and to calculate the value of sewage sludge within a given boundary/region• Diverse resource recovery systems (for nutrients, bioenergy, and raw substances for building materials) should be developed and applied for sewage sludge management, and in many cases, these systems should be integrated and optimized depending on the quality of sewage sludge and the scale of the region producing sewage sludge. Cost–benefit analysis should also be conducted so that the best technology available can be selected for different scenarios• Novel and environmentally friendly materials derived from sewage sludge, such as PHA, are appealing, and the potential of different bacterial species and recombinant strains should be explored further in the context of increased PHA yield and productivity• For sustainable management of sewage sludge, frameworks for risk assessment should be developed for different options of resource recovery, and the risks should be communicated to the public• New energy policies and regulations such as the climate change levy and enforcing source control to municipal sewers are critical in determining the sustainability of the future in sludge management。
机械类外文文献翻译(中英文翻译)
机械类外文文献翻译(中英文翻译)英文原文Mechanical Design and Manufacturing ProcessesMechanical design is the application of science and technology to devise new or improved products for the purpose of satisfying human needs. It is a vast field of engineering technology which not only concerns itself with the original conception of the product in terms of its size, shape and construction details, but also considers the various factors involved in the manufacture, marketing and use of the product.People who perform the various functions of mechanical design are typically called designers, or design engineers. Mechanical design is basically a creative activity. However, in addition to being innovative, a design engineer must also have a solid background in the areas of mechanical drawing, kinematics, dynamics, materials engineering, strength of materials and manufacturing processes.As stated previously, the purpose of mechanical design is to produce a product which will serve a need for man. Inventions, discoveries and scientific knowledge by themselves do not necessarily benefit people; only if they are incorporated into a designed product will a benefit be derived. It should be recognized, therefore, that a human need must be identified before a particular product is designed.Mechanical design should be considered to be an opportunity to use innovative talents to envision a design of a product, to analyze the systemand then make sound judgments on how the product is to be manufactured. It is important to understand the fundamentals of engineering rather than memorize mere facts and equations. There are no facts or equations which alone can be used to provide all the correct decisions required to produce a good design.On the other hand, any calculations made must be done with the utmost care and precision. For example, if a decimal point is misplaced, an otherwise acceptable design may not function.Good designs require trying new ideas and being willing to take a certain amount of risk, knowing that if the new idea does not work the existing method can be reinstated. Thus a designer must have patience, since there is no assurance of success for the time and effort expended. Creating a completely new design generally requires that many old and well-established methods be thrust aside. This is not easy since many people cling to familiar ideas, techniques and attitudes. A design engineer should constantly search for ways to improve an existing product and must decide what old, proven concepts should be used and what new, untried ideas should be incorporated.New designs generally have "bugs" or unforeseen problems which must be worked out before the superior characteristics of the new designs can be enjoyed. Thus there is a chance for a superior product, but only at higher risk. It should be emphasized that, if a design does not warrant radical new methods, such methods should not be applied merely for the sake of change.During the beginning stages of design, creativity should be allowedto flourish without a great number of constraints. Even though many impractical ideas may arise, it is usually easy to eliminate them in the early stages of design before firm details are required by manufacturing. In this way, innovative ideas are not inhibited. Quite often, more than one design is developed, up to the point where they can be compared against each other. It is entirely possible that the design which is ultimately accepted will use ideas existing in one of the rejected designs that did not show as much overall promise.Psychologists frequently talk about trying to fit people to the machines they operate. It is essentially the responsibility of the design engineer to strive to fit machines to people. This is not an easy task, since there is really no average person for which certain operating dimensions and procedures are optimum.Another important point which should be recognized is that a design engineer must be able to communicate ideas to other people if they are to be incorporated. Communicating the design to others is the final, vital step in the design process. Undoubtedly many great designs, inventions, and creative works have been lost to mankind simply because the originators were unable or unwilling to explain their accomplishments to others. Presentation is a selling job. The engineer, when presenting a new solution to administrative, management, or supervisory persons, is attempting to sell or to prove to them that this solution is a better one. Unless this can be done successfully, the time and effort spent on obtaining the solution have been largely wasted.Basically, there are only three means of communication available tous. These are the written, the oral, and the graphical forms. Therefore the successful engineer will be technically competent and versatile in all three forms of communication. A technically competent person who lacks ability in any one of these forms is severely handicapped. If ability in all three forms is lacking, no one will ever know how competent that person is!The competent engineer should not be afraid of the possibility of not succeeding in a presentation. In fact, occasional failure should be expected because failure or criticism seems to accompany every really creative idea. There is a great deal to be learned from a failure, and the greatest gains are obtained by those willing to risk defeat. In the final analysis, the real failure would lie in deciding not to make the presentation at all. To communicate effectively, the following questions must be answered:(1) Does the design really serve a human need?(2) Will it be competitive with existing products of rival companies?(3) Is it economical to produce?(4) Can it be readily maintained?(5) Will it sell and make a profit?Only time will provide the true answers to the preceding questions, but the product should be designed, manufactured and marketed only with initial affirmative answers. The design engineer also must communicate the finalized design to manufacturing through the use of detail and assembly drawings.Quite often, a problem will occur during the manufacturing cycle [3].It may be that a change is required in the dimensioning or tolerancing of a part so that it can be more readily produced. This fails in the category of engineering changes which must be approved by the design engineer so that the product function will not be adversely affected. In other cases, a deficiency in the design may appear during assembly or testing just prior to shipping. These realities simply bear out the fact that design is a living process. There is always a better way to do it and the designer should constantly strive towards finding that better way.Designing starts with a need, real or imagined. Existing apparatus may need improvements in durability, efficiently, weight, speed, or cost. New apparatus may be needed to perform a function previously done by men, such as computation, assembly, or servicing. With the objective wholly or partly defined, the next step in design is the conception of mechanisms and their arrangements that will perform the needed functions.For this, freehand sketching is of great value, not only as a record of one's thoughts and as an aid in discussion with others, but particularly for communication with one's own mind, as a stimulant for creative ideas.When the general shape and a few dimensions of the several components become apparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive east. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strength of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles ofmechanics, such as those of statics for reaction forces and for the optimumutilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress。
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The smart gridSmart grid is the grid intelligent (electric power), also known as the "grid" 2.0, it is based on the integration, high-speed bidirectional communication network, on the basis of through the use of advanced sensor and measuring technology, advanced equipme nt technology, the advancedcontrol method, and the application of advanced technology of decision support system, realize the power grid reliability, security, economic, efficient, environmental friendly and use the security target, its main features include self-healing, incentives and include user, against attacks, provide meet user requirements of power quality in the 21st century, allow all sorts of different power generation in the form of access, start the electric power market and asset optimizatio n run efficiently.The U.S. department of energy (doe) "the Grid of 2030" : a fully automated power transmission network, able to monitor and control each user and power Grid nodes, guarantee from power plants to end users among all the nodes in the whole process of transmission and distribution of information and energy bi-directional flow.China iot alliance between colleges: smart grid is made up of many parts, can be divided into:intelligent substation, intelligent power distribution network, intelli gent watt-hourmeter,intelligent interactive terminals, intelligent scheduling, smart appliances, intelligent building electricity, smart city power grid, smart power generation system, the new type of energy storage system.Now a part of it to do a simple i ntroduction. European technology BBS: an integration of all users connected to the power grid all the behavior of the power transmission network, to provide sustained and effective economic and security of power.Chinese academy of sciences, institute of electrical: smart grid is including all kinds of power generation equipment, power transmission and distribution network, power equipment and storage equipment, on the basis of the physical power grid will be modern advanced sensor measurement technology, network technology, communicationtechnology, computing technology, automationand intelligent control technology and physical grid highly integrated to form a new type of power grid, it can realize the observable (all the state of the equipment can monitor grid), can be controlled (able to control the power grid all the state of the equipment), fully automated (adaptive and self-healing) and system integrated optimization balance (power generation, transmission and distribution, and the optimization of the balance between electricity), so that the power system is more clean, efficient, safe and reliable.American electric power research institute: IntelliGrid is a composed of numerous automation system of power transmission and distribution power system, in a coordinated, effective and reliable way to achieve all of the power grid operation: have self-healing function;Rapid response to the electric power market and enterprise business requirements;Intelligent communication architecture, realizes the real-time, security, and flexible information flow, to provide users with reliable, economic power services. State grid electric power research institute, China: on the basis of the physical power grid (China's smart grid is based on high voltage network backbone network frame, different grid voltage level based on the coordinated development of strong power grid), the modern advanced sensor measurement technology, communication technology, information technology, computer technology and control technology and the physical power grid highly integrated to form a new type of power grid.It to fully meet user demand for electricity and optimize the allocation of resources, guarantee the safety, reliability and economy of power supply, meet environmental constraints, ens ure the quality of electric energy, to adapt to the development of power market, for the purpose of implementing the user reliable, economic, clean and interactive power supply and value-added services.BackgroundStrong smart grid development in the wor ld is still in its infancy, without a common precisely defined, its technology can be roughly divided into four areas: advanced Measurement system, advanced distribution operation, advanced transmission operation and advanced asset management.Advanced meas urement system main function is authorized to the user, make the system to establish a connection with load, enabling users to support the operationof the power grid;Advanced core distribution operation is an online real-time decision command, goal is to disaster prevention and control, realizing large cascading failure prevention;Advanced transmission operation main role is to emphasize congestion ma nagement and reduce the risk of the large-scale railway;Advanced asset management is installed in the system can provide the system parameters and equipments (assets) "health" condition of advanced sensor, and thereal-time information collected by integrat ion and resource management, modeling and simulation process, improve the operation and efficiency of power grid.The smart grid is an important application of Internet of things, and published in the journal of computer smart grid information system archit ecture research is carried on the detailed discussion on this, and the architecture of the smart grid information system are analyzed.The market shareThe establishment of the smart grid is a huge historical works.At present many complicated smart grid project is underway, but the gap is still great.For the provider of the smart grid technology, promote the development of facing the challenges of the distribution network system i s upgrading, automation and power distribution substation transportation, smart grid network and intelligent instruments.According to the latest report of parker investigators, smart grid technology market will increase from $2012 in 33 billion to $2020 in 73 billion, eight years, the market accumulated up to $494 billion.China smart grid industry market foresight and investment forward-looking strategic planning analysis, points out that in our country will be built during the "twelfth five-year""three vertical and three horizontal and one ring" of uhv ac lines, and 11 back to u hv dc transmission project construction, investment of 300 billion yuan.Although during the period of "much starker choices-and graver consequences-in" investment slowed slightly, the investment is 250 billion yuan.By 2015, a wide range of national power grid, long distance transmission capacity will reach 250 million kilowatts, power transmission of 1.15 trillion KWH per year, to support the new 145 million kilowatts of clean energy generation given and sent out, can satisfy the demand of morethan 1 million electric cars, a grid resource configuration optimization ability, economic efficiency, safety and intelligent levels will be fully promoted.The abroad application of analysisIn terms of power grid development foundation, national electricity dema nd tends to be saturated, the grid after years of rapid development, architecture tends to be stable, mature, have a more abundant supply of electric power transmission and distribution capacity.Germany has "E - Energy plan, a total investment of 140 million euros, from 2009 to 2012, four years, six sites across the country to the smart grid demonstration experiment.At the same time also for wind power and electric car empirical experiments, testing and management of power consumption of the Internet.Big companies such as Germany's Siemens, SAP and Swiss ABB are involved in this plan.To smart grid Siemens 2014 annual market scale will reach 30 billion euros, and plans to take a 20% market share, make sure order for 6 billion euros a year.The advanced nat ureCompared with the existing grid, smart grid, reflects the power flow, information flow and business flow marked characteristics of highly integration, its advancement and advantage mainly displays in:(1) has a strong foundation of grid system and te chnical support system, able to withstand all kinds of external disturbance and attacks, can adapt to large-scale clean energy and renewable energy access, strong sex of grid reinforced and ascend.(2) the information technology, sensor technology, automatic control technology organic combination with power grid infrastructure, a panoramic view of available power grid information, timely detection, foresee the possibility of failure.Fault occurs, the grid can be quickly isolate fault,realize self recovery,to avoid the occurrence of blackouts.(3) flexible ac/dc transmission, mesh factory coordination, intelligent scheduling, power storage, and distribution automation technology widespread application, makes the control of power grid operation more flexibl e,economic, and can adapt to a large number of distributed power supply, power grid and electric vehicle charging and discharging facility access.(4) communication, information, and the integrated use of modern management technology, will greatly improve the efficiency of power equipment, and reduce the loss of electrical power, making the operation of power grid is more economic and efficient.(5) the height of the real-time and non real-time information integration, sharing and utilization, to run the show management comprehensive, complete and fine grid operation state diagram, at the same time can provide decision support, control scheme and the corresponding response plans.(6) to establish a two-way interactive service mode, users can real-time understand the status of the power supply ability, power quality, price and power outage information, reasonable arrangement of electric equipment use;The electric power enterprise can obtain the user's electricity information in detail, to provide more value-added services.developmentaltrend"Twelfth five-year" period, the state grid will invest 500 billion yuan to build the connection of large ene rgy base and center of the "three horizontal three longitudinal" main load of ultra high voltage backbone network frame and 13 back to long branch, engineering, to form the core of the world first-class strong smart grid."Strong smart grid technology standards promulgated by the state grid system planning", has been clear about the strong smart grid technology standards roadmap, is the world's first used to guide the development of smart grid technology guiding standards.SGC planning is to built 2015 basic information, automation, interaction characteristics of strong smart grid, formed in north China, central China, east China, for the end to the northwest and northeast power grid for sending the three synchronous power grid, the grid resource allocati on ability, economic efficiency and safety level, technology level and improve intelligent level.(1) the smart grid is the inevitable developing trend ofpower grid technology.Such as communication, computer, automation technology has extensive applicati on in the power grid, and organic combination with traditional electric power technology, and greatly improve the intelligent level of the power grid.Sensor technology and information technology application in the power grid, the system state analysis and auxiliary decision provides the technical support, make it possible to grid self-healing.Scheduling technology, automation technology and the mature development of flexible transmission technology, for the development and utilization of renewable energy an d distributed power supply provides the basic guarantee.The improvement of the communication network and the popularization and application of user information collection technology, promote the two-way interaction with users of the grid.With the further development of various new technologies, application and highly integrated with the physical power grid, smart grid arises at the historic moment.(2) the development of smart grid is the inevitable choice of social and economic development.In order to ach ieve the development of clean energy, transport and given power grid must increase its flexibility and compatibility.To withstand the increasingly frequent natural disasters and interference, intelligent power grid must rely on means to improve its securit y defense andself-healing ability.In order to reduce operating costs, promote energy conservation and emissions reduction, power grid operation must be more economic and efficient, at the same time must to intelligent control of electric equipment, reduce electricity consumption as much as possible.Distributed generation and energy storage technology and the rapid development of electric cars, has changed the traditional mode of power supply, led power flow, information flow, business flow constantly fusion, in order to satisfy the demands of increasingly diverse users.PlanJapan plans to all the popularity of smart grid in 2030, officer of the people at the same time to promote the construction of overseas integrated smart grid.In the field of battery, Japanese firms' global market share goal is to strive to reach 50%, with about 10 trillion yen in the market.Japan's trade ministry has set up a "about the next generation of energy systems international standardizationresearch institute", the japan-american established in Okinawa and Hawaii for smart grid experimental project [6].Learns in the itu, in 2020 China will be built in high power grid with north China, east China, China as the center, northeast, northwest 750 kv uhv power grid as the sending, connecting each big coal base, large hydropower bases, big base for nuclear power, renewable energy base, the coordinated development of various grid strong smart grid.In north China, east China, China high voltage synchronous ZhuWangJia six "five longitudi nal and transverse" grid formation.The direction ofIn the green energy saving consciousness, driven by the smart grid to become the world's countries to develop a focus areas.The smart grid is the electric power network, is a self-healing, let consum ers to actively participate in, can recover from attacks and natural disasters in time, to accommodate all power generation and energy storage, can accept the new product, service and market, optimize asset utilization and operation efficiency, provide qua lity of power supply for digital economy.Smart grid based on integrated, high-speed bidirectional communication network foundation, aims to use advanced sensor and measuring technology, advanced equipment, technology and advanced control methods, and adv anced technology of decision support system, realize the power grid reliability, security, economic, efficient, environmental friendly, and the use of safe run efficiently.Its development is a gradual progressive evolution, is a radical change, is the product of the coordinated development of new and existing technologies, in ad dition to the network and smart meters also included the wider range.Grid construction in high voltage network backbone network frame, all levels of the coordinated development, informatization, automation, interaction into the characteristics of strong smart grid, improve network security, economy, adaptability and interactivity, strength is the foundation, intelligence is the key.meaningIts significance is embodied in the foll owing aspects:(1) has the strong ability of resources optimization allocation.After the completion of the smart grid in China, will implement the big water and electricity, coal, nuclear power, large-scale renewable energy across regions, long distance, large capacity, low loss, high efficiency, regional power exchange capacity improved significantly.(2) have a higher level of safe and stable operation.Grid stability and power supply reliability will be improved, the safety of the power grid close coord ination between all levels of line, have theability to against sudden events and serious fault, can effectively avoid the happening of a wide range of chain failure, improve power supply reliability, reduce the power loss.(3) to adapt and promote the dev elopment of clean energy.Grid will have wind turbines power prediction and dynamic modeling, low voltage across, and active reactive power control and regular units quickly adjust control mechanism, combined with the application of large capacity storage technology, the operation control of the clean energy interconnection capacity will significantly increased, and make clean energy the more economical, efficient and reliable way of energy supply.(4)implementing highly intelligent power grid scheduling.Co mpleted vertical integration, horizontal well versed in the smart grid scheduling technology support system, realize the grid online intelligent analysis, early warning and decision-making, and all kinds of new transmission technology and equipment of effi cient control and lean control of ac/dc hybrid power grid.(5)can satisfy the demands of electric cars and other new type electric power user services.Would be a perfect electric vehicle charging and discharging supporting infrastructure network, can meet the needs of the development of the electric car industry, to meet the needs of users, realize high interaction of electric vehicles and power grid.(6) realize high utilization and whole grid assets life cycle management.Can realize electric grid system of the whole life cycle management plan.Through smart grid scheduling and demand side management, power grid assets utilization hours, power grid assets efficiency improvedsignificantly.(7) to realize power convenient interaction between the user and the grid.Will form a smart electricity interactive platform, improving the demand side management, to provide users with high-quality electric power service.At the same time, the comprehensive utilization of the grid can be distributed power supply, intelli gent watt-hour meter, time-sharing electricity price policy and the electric vehicle charging and discharging mechanism, effectively balance electric load, reduce the peak valley load difference, reduce the power grid and power construction costs.(8)grid management informatization and the lean.Covering power grid will each link of communication network system, realize the power grid operation maintenance integrated regulation, data management, information grid spatial information services, and production and scheduling application integration, and other functions, to realize all-sided management informatization and the lean.(9) grid infrastructure of value-added service potential into full play.In power at the same time, the national strategy of "triple play" of services, to provide users with community advertising, network television, voice and other integrated services, such as water supply, heating, gas industry informatization, interactive platform support, expand the range of value-added services and improve the grid infrastructure and capacity, vigorously promote the development of smart city.(10)Gridto promote the rapid development of related industries.Electric power industry belongsto the capital-intensive and technology-intensive industry, has the characteristics of huge investment, long industrial chain.Construction of smart grid, which is beneficial to promote equipment manufacturing information and communication industry technology upgrade, for our country to occupy the high ground to lay the foundation in the field of electric power equipment manufacturing.Important significanceLife is convenientThe construction of strong smart grid, will promote the development of intelligent community, smart city, improve people's quality of life.(1) to make life more convenient.Home intelligent power system can not onlyrealize the real-time control of intelligent home appliances such as air conditioning, water heater and remote control;And can provide telecommunication network, Internet, radio and television network access services;Through intelligent watt-hour meter will also be able to achieve au tomatic meter reading and automatic transfer fee, and other functions.(2) to make life more low carbon.Smart grid can access to the small family unit such as wind power and photovoltaic roof, pushing forward the large-scale application of electric cars, so as to raise the proportion of clean energy consumption, reduce the pollution of the city.(3) to make life more economical.The smart grid can promote power user role transformation, both electricity and sell electricity twofold properties;To build a family for the user electricity integrated services platform, to help users choose the way of electricity, save energy, reduce the energy expense.Produce benefitThe development of a strong smart grid, the grid function gradually extended to promote the optim al allocation of energy resources, guarantee the safe and stable operation of power system, providing multiple open power service, promote the development of strategic emerging industries, and many other aspects.As China's important energy delivery and configuration platform, strong and smart grid from the investment construction to the operation of production process will be for the national economic development, energy production and use, environmental protection bring great benefits.(1)in power system.Can save system effective capacity;Reducing the system total power generation fuel cost;Improving the efficiency of grid equipment, reduce construction investment;Ascension grid transmission efficiency, reduce the line loss.(2)in terms of power customers.Can realize the bidirectional interaction, to provide convenient services;Improving terminal energy efficiency, save power consumption;To improve power supply reliability, and improve power quality.(3) in the aspect of energy saving and environment.Can improve the efficiency of energy utilization, energy conservation and emissions reduction benefit.To promote clean energy development, realize the alternative reductionbenefits;Promote the overall utilization of land resources, saving land usage.(4) other aspects.Can promote the economic development, jobs;To ensure the safety of energy supply;Coal for power transmission and improve the efficiency of energy conversion, reducing the transportation pressure.Propulsion system(1) can effectively improve t he security of power system and power supply e of strong smart grid "self-healing" function, can accurately and quickly isolate the fault components, and in the case of less manual intervention make the system quickly returned to normal, so as to improve the security and reliability of power supply system.(2) the power grid to realize the sustainable development.Strong smart grid technology innovation can promote the power grid construction, implementation technology, equipment, operation an d management of all aspects of ascension, to adapt to the electric power market demand, promote the scientific and sustainable development of power grid.(3) reduce the effective ing the power load characteristics in different regions of the ch aracteristics of big differences through the unification of the intelligent dispatching, the peakand peak shaving, such as networking benefit;At the same time through the time-sharing electricity price mechanism, and guide customers low power, reduce the peak load, so as to reduce the effective capacity.(4) to reduce the system power generation fuel costs.Construction of strong smart grid, which can meet the intensive development of coal base, optimization of power distribution in our country, thereby red ucing fuel transportation cost;At the same time, by reducing the peak valley load difference, can improve the efficiency of thermal power unit, reduce the coal consumption, reduce the cost.(5)improve the utilization efficiency of grid equipment.First of all, by improving the power load curve, reduce the peak valley is poor, improve the utilization efficiency of grid equipment;Second, by self diagnosis, extend the life of the grid infrastructure.(6) reduce the line loss.On the important basis of uhv transmission technology of strong smart grid, will greatly reduce the loss rate in the electric power transmission;Intelligent scheduling system, flexible transmission technology and real-time two-way interaction with customers, can optimize the tide distribut ion, reducing line loss;At the same time, the construction and application of distributed power supply, also reduce the network loss of power transmission over a long distance.Allocation of resourcesEnergy resources and energy demand in the reverse distribution in our country, more than 80% of the coal, water power and wind power resource distribution in the west, north, and more than 75% of the energy demand is concentrated in the eastern and central regions.Energy resources and energy demand unbalance d distribution of basic national conditions, demand of energy needs to be implemented nationwide resource optimizing configuration.The construction of strong smart grid, for optimal allocation of energy resources provides a good platform.Strong smart grid is completed, will form a strong structure and sending by the end of the power grid power grid, power capacity significantly strengthened, and the formation of the intensity, stiffness of uhv power transmission network, realize the big water and electricit y, coal, nuclear power, large-scale renewable energy across regions, long distance, large capacity, low loss, high efficiency transport capacity significantly increased power a wide range of energy resources optimization.Energy developmentThe development and utilization of clean energy such as wind power and solar energy to produce electricity is given priority to, in the form of the construction of strong smart grid can significantly improve the grid's ability to access, given and adjust clean energy, vigorously promote the development of clean energy.(1) smart grid, the application of advanced control technology and energy storage technology, perfect the grid-connected clean energy technology standards, improve the clean energy acceptance ability.Clean energy base, (2) the smart grid, rational planning of large-scale space truss structure and sending the power structure, application of uhv, flexible transmission technology, meet the requirements of the large-scale clean energy electricitytransmission.(3) the smart grid for large-scale intermittent clean energy to carry on the reasonable and economic operation, improve the operation performance of clean energy production.(4) intelligent with electric equipment, can achieve acceptance and coordinated cont rol of distributed energy, realize the friendly interaction with the user, the user to enjoy the advantages of new energy power.Energy conservation and emissions reductionStrong smart grid construction to promote energy conservation and emissions reduc tion,development of low carbon economy is of great significance: (1) to support large-scale clean energy unit net, accelerate the development of clean energy, promote our country the optimization of energy structure adjustment;(2) to guide users reasonable arrangement of electricity, reducing peak load, stable thermal power unit output, reduce power generation coal consumption;(3) promote ultra-high voltage, flexible transmission, promotion and application of advanced technology such as economic operation, reduce the transmission loss, improve power grid operation efficiency;(4) to realize the power grid to interact with users effectively, promote intelligent power technology, improve the efficiency of electricity;(5) to promote the electric car of large-scale application, promote the development of low-carbon economy, achieve emission reduction benefits.There are three milestones of the concept of smart grid development:The first is 2006, the United States "smart grid" put forward by the IBM solution.IBM smart grid is mainly to solve, improve reliability and safety of power grid from its release in China, the construction of the smart grid operations management innovation - the new train of thought on the development of China's power "the white paper can be seen that the scheme provides a larger framework, through to the electric power production, transmission, the optimization of all aspects of retail management, for the relevant enterprises to improve operation efficiency and reliability, reduce cost dep icts a blueprint.IBM is a marketing strategy.The second is the energy plan put forward by the Obama took office, in addition to the published plan, the United States will also focus on cost $120 billion a year circuit。