英文文献及中文翻译
英文文献翻译
外文文献原稿和译文原稿Sodium Polyacrylate:Also known as super-absorbent or “SAP”(super absorbent polymer), Kimberly Clark used to call it SAM (super absorbent material). It is typically used in fine granular form (like table salt). It helps improve capacity for better retention in a disposable diaper, allowing the product to be thinner with improved performance and less usage of pine fluff pulp. The molecular structure of the polyacrylate has sodium carboxylate groups hanging off the main chain. When it comes in contact with water, the sodium detaches itself, leaving only carboxylions. Being negatively charged, these ions repel one another so that the polymer also has cross-links, which effectively leads to a three-dimensional structure. It has hige molecular weight of more than a million; thus, instead of getting dissolved, it solidifies into a gel. The Hydrogen in the water (H-O-H) is trapped by the acrylate due to the atomic bonds associated with the polarity forces between the atoms. Electrolytes in the liquid, such as salt minerals (urine contains 0.9% of minerals), reduce polarity, thereby affecting superabsorbent properties, especially with regard to the superabsorbent capacity for liquid retention. This is the main reason why diapers containing SAP should never be tested with plain water. Linear molecular configurations have less total capacity than non-linear molecules but, on the other hand, retention of liquid in a linear molecule is higher than in a non-linear molecule, due to improved polarity. For a list of SAP suppliers, please use this link: SAP, the superabsorbent can be designed to absorb higher amounts of liquids (with less retention) or very high retentions (but lower capacity). In addition, a surface cross linker can be added to the superabsorbent particle to help it move liquids while it is saturated. This helps avoid formation of "gel blocks", the phenomenon that describes the impossibility of moving liquids once a SAP particle gets saturated.History of Super Absorbent Polymer ChemistryUn til the 1980’s, water absorbing materials were cellulosic or fiber-based products. Choices were tissue paper, cotton, sponge, and fluff pulp. The water retention capacity of these types of materials is only 20 times their weight – at most.In the early 1960s, the United States Department of Agriculture (USDA) was conducting work on materials to improve water conservation in soils. They developed a resin based on the grafting of acrylonitrile polymer onto the backbone of starch molecules (i.e. starch-grafting). The hydrolyzed product of the hydrolysis of this starch-acrylonitrile co-polymer gave water absorption greater than 400 times its weight. Also, the gel did not release liquid water the way that fiber-based absorbents do.The polymer came to be known as “Super Slurper”.The USDA gave the technical know how several USA companies for further development of the basic technology. A wide range of grating combinations were attempted including work with acrylic acid, acrylamide and polyvinyl alcohol (PVA).Since Japanese companies were excluded by the USDA, they started independent research using starch, carboxy methyl cellulose (CMC), acrylic acid, polyvinyl alcohol (PVA) and isobutylene maleic anhydride (IMA).Early global participants in the development of super absorbent chemistry included Dow Chemical, Hercules, General Mills Chemical, DuPont, National Starch & Chemical, Enka (Akzo), Sanyo Chemical, Sumitomo Chemical, Kao, Nihon Starch and Japan Exlan.In the early 1970s, super absorbent polymer was used commercially for the first time –not for soil amendment applications as originally intended –but for disposable hygienic products. The first product markets were feminine sanitary napkins and adult incontinence products.In 1978, Park Davis (d.b.a. Professional Medical Products) used super absorbent polymers in sanitary napkins.Super absorbent polymer was first used in Europe in a baby diaper in 1982 when Schickendanz and Beghin-Say added the material to the absorbent core. Shortly thereafter, UniCharm introduced super absorbent baby diapers in Japan while Proctor & Gamble and Kimberly-Clark in the USA began to use the material.The development of super absorbent technology and performance has been largely led by demands in the disposable hygiene segment. Strides in absorption performance have allowed the development of the ultra-thin baby diaper which uses a fraction of the materials – particularly fluff pulp – which earlier disposable diapers consumed.Over the years, technology has progressed so that there is little if any starch-grafted super absorbent polymer used in disposable hygienic products. These super absorbents typically are cross-linked acrylic homo-polymers (usually Sodium neutralized).Super absorbents used in soil amendments applications tend to be cross-linked acrylic-acrylamide co-polymers (usually Potassium neutralized).Besides granular super absorbent polymers, ARCO Chemical developed a super absorbent fiber technology in the early 1990s. This technology was eventually sold to Camelot Absorbents. There are super absorbent fibers commercially available today. While significantly more expensive than the granular polymers, the super absorbent fibers offer technical advantages in certain niche markets including cable wrap, medical devices and food packaging.Sodium polyacrylate, also known as waterlock, is a polymer with the chemical formula [-CH2-CH(COONa)-]n widely used in consumer products. It has the ability to absorb as much as 200 to 300 times its mass in water. Acrylate polymers generally are considered to possess an anionic charge. While sodium neutralized polyacrylates are the most common form used in industry, there are also other salts available including potassium, lithium and ammonium.ApplicationsAcrylates and acrylic chemistry have a wide variety of industrial uses that include: ∙Sequestering agents in detergents. (By binding hard water elements such as calcium and magnesium, the surfactants in detergents work more efficiently.) ∙Thickening agents∙Coatings∙Fake snowSuper absorbent polymers. These cross-linked acrylic polymers are referred to as "Super Absorbents" and "Water Crystals", and are used in baby diapers. Copolymerversions are used in agriculture and other specialty absorbent applications. The origins of super absorbent polymer chemistry trace back to the early 1960s when the U.S. Department of Agriculture developed the first super absorbent polymer materials. This chemical is featured in the Maximum Absorbency Garment used by NASA.译文聚丙烯酸钠聚丙烯酸钠,又可以称为超级吸收剂或者又叫高吸水性树脂,凯博利克拉克教授曾经称它为SAM即:超级吸收性物质。
中英文文献以及翻译(化工类)
Foreign material:Chemical Industry1.Origins of the Chemical IndustryAlthough the use of chemicals dates back to the ancient civilizations, the evolution of what we know as the modern chemical industry started much more recently. It may be considered to have begun during the Industrial Revolution, about 1800, and developed to provide chemicals roe use by other industries. Examples are alkali for soapmaking, bleaching powder for cotton, and silica and sodium carbonate for glassmaking. It will be noted that these are all inorganic chemicals. The organic chemicals industry started in the 1860s with the exploitation of William Henry Perkin’s discovery if the first synthetic dyestuff—mauve. At the start of the twentieth century the emphasis on research on the applied aspects of chemistry in Germany had paid off handsomely, and by 1914 had resulted in the German chemical industry having 75% of the world market in chemicals. This was based on the discovery of new dyestuffs plus the development of both the contact process for sulphuric acid and the Haber process for ammonia. The later required a major technological breakthrough that of being able to carry out chemical reactions under conditions of very high pressure for the first time. The experience gained with this was to stand Germany in good stead, particularly with the rapidly increased demand for nitrogen-based compounds (ammonium salts for fertilizers and nitric acid for explosives manufacture) with the outbreak of world warⅠin 1914. This initiated profound changes which continued during the inter-war years (1918-1939).Since 1940 the chemical industry has grown at a remarkable rate, although this has slowed significantly in recent years. The lion’s share of this growth has been in the organic chemicals sector due to the development and growth of the petrochemicals area since 1950s. The explosives growth in petrochemicals in the 1960s and 1970s was largely due to the enormous increase in demand for synthetic polymers such as polyethylene, polypropylene, nylon, polyesters and epoxy resins.The chemical industry today is a very diverse sector of manufacturing industry, within which it plays a central role. It makes thousands of different chemicals whichthe general public only usually encounter as end or consumer products. These products are purchased because they have the required properties which make them suitable for some particular application, e.g. a non-stick coating for pans or a weedkiller. Thus chemicals are ultimately sold for the effects that they produce.2. Definition of the Chemical IndustryAt the turn of the century there would have been little difficulty in defining what constituted the chemical industry since only a very limited range of products was manufactured and these were clearly chemicals, e.g., alkali, sulphuric acid. At present, however, many intermediates to products produced, from raw materials like crude oil through (in some cases) many intermediates to products which may be used directly as consumer goods, or readily converted into them. The difficulty cones in deciding at which point in this sequence the particular operation ceases to be part of the chemical industry’s sphere of activities. To consider a specific example to illustrate this dilemma, emulsion paints may contain poly (vinyl chloride) / poly (vinyl acetate). Clearly, synthesis of vinyl chloride (or acetate) and its polymerization are chemical activities. However, if formulation and mixing of the paint, including the polymer, is carried out by a branch of the multinational chemical company which manufactured the ingredients, is this still part of the chemical industry of does it mow belong in the decorating industry?It is therefore apparent that, because of its diversity of operations and close links in many areas with other industries, there is no simple definition of the chemical industry. Instead each official body which collects and publishes statistics on manufacturing industry will have its definition as to which operations are classified as the chemical industry. It is important to bear this in mind when comparing statistical information which is derived from several sources.3. The Need for Chemical IndustryThe chemical industry is concerned with converting raw materials, such as crude oil, firstly into chemical intermediates and then into a tremendous variety of other chemicals. These are then used to produce consumer products, which make our livesmore comfortable or, in some cases such as pharmaceutical produces, help to maintain our well-being or even life itself. At each stage of these operations value is added to the produce and provided this added exceeds the raw material plus processing costs then a profit will be made on the operation. It is the aim of chemical industry to achieve this.It may seem strange in textbook this one to pose the question “do we need a chemical industry?” However trying to answer this question will provide(ⅰ) an indication of the range of the chemical industry’s activities, (ⅱ) its influence on our lives in everyday terms, and (ⅲ) how great is society’s need for a chemical industry. Our approach in answering the question will be to consider the industry’s co ntribution to meeting and satisfying our major needs. What are these? Clearly food (and drink) and health are paramount. Other which we shall consider in their turn are clothing and (briefly) shelter, leisure and transport.(1)Food. The chemical industry makes a major contribution to food production in at least three ways. Firstly, by making available large quantities of artificial fertilizers which are used to replace the elements (mainly nitrogen, phosphorus and potassium) which are removed as nutrients by the growing crops during modern intensive farming. Secondly, by manufacturing crop protection chemicals, i.e., pesticides, which markedly reduce the proportion of the crops consumed by pests. Thirdly, by producing veterinary products which protect livestock from disease or cure their infections.(2)Health. We are all aware of the major contribution which the pharmaceutical sector of the industry has made to help keep us all healthy, e.g. by curing bacterial infections with antibiotics, and even extending life itself, e.g. ß–blockers to lower blood pressure.(3)Clothing. The improvement in properties of modern synthetic fibers over the traditional clothing materials (e.g. cotton and wool) has been quite remarkable. Thus shirts, dresses and suits made from polyesters like Terylene and polyamides like Nylon are crease-resistant, machine-washable, and drip-dry or non-iron. They are also cheaper than natural materials.Parallel developments in the discovery of modern synthetic dyes and the technology to “bond” th em to the fiber has resulted in a tremendous increase in the variety of colors available to the fashion designer. Indeed they now span almost every color and hue of the visible spectrum. Indeed if a suitable shade is not available, structural modification of an existing dye to achieve this canreadily be carried out, provided there is a satisfactory market for the product.Other major advances in this sphere have been in color-fastness, i.e., resistance to the dye being washed out when the garment is cleaned.(4)Shelter, leisure and transport. In terms of shelter the contribution of modern synthetic polymers has been substantial. Plastics are tending to replace traditional building materials like wood because they are lighter, maintenance-free (i.e. they are resistant to weathering and do not need painting). Other polymers, e.g. urea-formaldehyde and polyurethanes, are important insulating materials f or reducing heat losses and hence reducing energy usage.Plastics and polymers have made a considerable impact on leisure activities with applications ranging from all-weather artificial surfaces for athletic tracks, football pitches and tennis courts to nylon strings for racquets and items like golf balls and footballs made entirely from synthetic materials.Like wise the chemical industry’s contribution to transport over the years has led to major improvements. Thus development of improved additives like anti-oxidants and viscosity index improves for engine oil has enabled routine servicing intervals to increase from 3000 to 6000 to 12000 miles. Research and development work has also resulted in improved lubricating oils and greases, and better brake fluids. Yet again the contribution of polymers and plastics has been very striking with the proportion of the total automobile derived from these materials—dashboard, steering wheel, seat padding and covering etc.—now exceeding 40%.So it is quite apparent even from a brief look at the chemical industry’s contribution to meeting our major needs that life in the world would be very different without the products of the industry. Indeed the level of a country’s development may be judged by the production level and sophistication of its chemical industry4. Research and Development (R&D) in Chemical IndustriesOne of the main reasons for the rapid growth of the chemical industry in the developed world has been its great commitment to, and investment in research and development (R&D). A typical figure is 5% of sales income, with this figure being almost doubled for the most research intensive sector, pharmaceuticals. It is important to emphasize that we are quoting percentages here not of profits but of sales income, i.e. the total money received, which has to pay for raw materials, overheads, staff salaries, etc. as well. In the past this tremendous investment has paid off well, leading to many useful and valuable products being introduced to the market. Examplesinclude synthetic polymers like nylons and polyesters, and drugs and pesticides. Although the number of new products introduced to the market has declined significantly in recent years, and in times of recession the research department is usually one of the first to suffer cutbacks, the commitment to R&D remains at a very high level.The chemical industry is a very high technology industry which takes full advantage of the latest advances in electronics and engineering. Computers are very widely used for all sorts of applications, from automatic control of chemical plants, to molecular modeling of structures of new compounds, to the control of analytical instruments in the laboratory.Individual manufacturing plants have capacities ranging from just a few tones per year in the fine chemicals area to the real giants in the fertilizer and petrochemical sectors which range up to 500,000 tonnes. The latter requires enormous capital investment, since a single plant of this size can now cost $520 million! This, coupled with the widespread use of automatic control equipment, helps to explain why the chemical industry is capital-rather than labor-intensive.The major chemical companies are truly multinational and operate their sales and marketing activities in most of the countries of the world, and they also have manufacturing units in a number of countries. This international outlook for operations, or globalization, is a growing trend within the chemical industry, with companies expanding their activities either by erecting manufacturing units in other countries or by taking over companies which are already operating there.化学工业1.化学工业的起源尽管化学品的使用可以追溯到古代文明时代,我们所谓的现代化学工业的发展却是非常近代(才开始的)。
现代包装机械设备毕业课程设计外文文献翻译、中英文翻译
1 英文文献翻译1.1 Modern PackagingAuthor:Abstract1. Changing Needs and New RolesLooking back, historical changes are understandable and obvious. That all of them have had an impact on the way products are brought, consumed and packaged is also obvious. What is not so obvious is what tomorrow will bring. Yet, it is to the needs, markets, and conditions of tomorrow that packaging professionals must always turn their attention.The forces that drove packaging during the Industry Revolution continue to operate today. The consumer society continues to grow and is possibly best described by a 1988s bumper sticker, “Born to Shop”. We consume goods today at a rate 4 to 5 times greater than we did as recently as 1935. Most of these goods are not essential to survival; they constitute what we may call “the good life”.In the second half of the 20th century, the proliferation of goods was so high that packaging was forced into an entirely new role, that of providing the motivation rather than presenting the goods itself. On a shelf of 10 competing products, all of them similar in performance and quality, the only method of differentiating became the package itself. Marketer aimed at lifestyles, emotional values, subliminal images, features, and advantages beyond the basic product rather than the competitor’s. In some in instances, the package has become the product, and occasionally packaging has become entertainment.A brand product to carry the product manufacturer or product sales of theretailer’s label, usually by the buyer as a quality assessment guidance. In some cases, competing brands of product quality is almost no difference, a difference is the sale of its packaging. An interesting visually attractive packaging can give a key marketing advantage and convince impulse spending. However, the packaging should accurately reflect the quality of products/brand value in order to avoid the disappointment of consumers, encourage repeat purchases and build brand loyalty. Ideally, the product should exceed customer expectations.2. Packaging and the Modern Industrial SocietyThe importance of packaging to a modern industrial society is most evident when we examine the food-packaging sector. Food is organic in nature, having an animal or plant source. One characteristic of such organic matter is that, by and large, it has a limited natural biological life.A cut of meat, left to itself, might be unfit for human consumption by the next day. Some animal protein products, such as seafood, can deteriorate within hours.The natural shelf life of plant-based food depends on the species and plant involved. Pulpy fruit portions tend to have a short life span, while seed parts, which in nature have to survive at least separated from the living plant are usually short-lived.In addition to having a limited natural shelf life, most food is geographically and season-ally specific. Thus, potatoes and apples are grown in a few North American geographical regions and harvest during a short maturation period. In a world without packaging,we would need to live at the point of harvest to enjoy these products, and our enjoyment of them would be restricted to the natural biological life span of each. It is by proper storage, packaging and transport techniques that we are able to deliver fresh potatoes and apples, or the products derived from them, throughout the year and throughout the country. Potato-whole,canned, powdered, flaked, chipped, frozen, and instant is available, anytime, anywhere. This ability gives a society great freedom and mobility. Unlike less-developed societies, we are no longer restricted in our choice of where to live, since we are no longer tied to the food-producing ability of an area. Food production becomes more specialized and efficient with the growth of packaging. Crops and animal husbandry are moved to where their production is most economical, without regard to the proximity of a market. Most important, we are free of the natural cycles of feast and famine that are typical of societies dependent on natural regional food-producing cycles.Central processing allows value recovery from what would normally be waste by products of the processed food industry from the basis of other sub-industries. Chicken feathers are high in protein and, properly mill and treated, can be fed back to the next generation of chickens. Vegetable waste is fed to cattle or pigs. Bagasse, the waste cane from sugar pressing, is a source of fiber for papermaking. Fish scales are refined to make additives for paints and nail polish.The economical manufacture of durable goods also depends on good packaging.A product's cost is directly related to production volume. The business drive to reduce costs in the supply chain must be carefully balanced against the fundamental technical requirements for food safety and product integrity, as well as the need to ensure an. efficient logistics service. In addition, there is a requirement to meet the aims of marketing to protect and project brand image through value-added pack design. The latter may involve design inputs that communicate distinctive, aesthetically pleasing, ergonomic, functional and/or environmentally aware attributes. But for a national or international bicycle producer to succeed, it must be a way of getting the product to a market, which may be half a world away. Again, sound packaging, in this case distributionpackaging, is a key part of the system.Some industries could not exist without an international market. For example, Canada is a manufacturer of irradiation equipment, but the Canadian market (which would account for perhaps one unit every several years) could not possibly support such a manufacturing capability. However, by selling to the world, a manufacturing facility becomes viable. In addition to needing packaging for the irradiation machinery and instrumentation, the sale of irradiation equipment requires the sale packaging and transport of radioactive isotopes, a separate challenge in itself. In response to changing consumer lifestyles, the large retail groups and the food service industry development. Their success has been involved in a competition fierce hybrid logistics, trade, marketing and customer service expertise, all of which is dependent on the quality of packaging. They have in part led to the expansion of the dramatic range of products offered, technology innovation, including those in the packaging. Supply retail, food processing and packaging industry will continue to expand its international operations. Sourcing products around the world more and more to assist in reducing trade barriers. The impact of the decline has been increased competition and price pressure. Increased competition led to the rationalization of industrial structure, often in the form of mergers and acquisitions. Packaging, it means that new materials and shapes, increased automation, packaging, size range extension of lower unit cost. Another manufacturer and mergers and acquisitions, the Group's brand of retail packaging and packaging design re-evaluation of the growing development of market segmentation and global food supply chain to promote the use of advanced logistics and packaging systems packaging logistics system is an integral part of, and played an important role in prevention in the food supply or reduce waste generation.3. World Packaging.This discussion has referred to primitive packaging and the evolution of packaging functions. However, humankind's global progress is such that virtually every stage in the development of society and packaging is present somewhere in the world today. Thus, a packager in a highly developed country will agonize over choice of package type, hire expensive marketing groups to develop images to entice the targeted buyer and spend lavishly on graphics. In less-developed countries, consumers are happy to have food, regardless of the package. At the extreme, consumers will bring their own packages or will consume food on the spot, just as they did 2000 years ago.Packagers from the more developed countries sometimes have difficulty working with less-developed nations, for the simple reason that they fail to understand that their respective packaging priorities are completely different. Similarly, developing nations trying to sell goods to North American markets cannot understand our preoccupation with package and graphics.The significant difference is that packaging plays a different role in a market where rice will sell solely because it is available. In the North American market, the consumer may be confronted by five different companies offering rice in 30 or so variations. If all the rice is good and none is inferior, how does a seller create a preference for his particular rice? How does he differentiate? The package plays a large role in this process.The package-intensive developed countries are sometimes criticized for over packaging, and certainly over-packaging does exist. However, North Americans also enjoy the world's cheapest food, requiring only about 11 to 14% of our disposable income. European food costs are about 20% of disposable income, and in the less-developed countries food can take 95%of family income.4. The status and development trend of domestic and international packaging machineryWorldwide, the history of the development of the packaging machinery industry is relatively short, science and technology developed in Europe and America in general started in the 20th century until the 1950s the pace greatly accelerated.From the early 20th century, before the end of World War II World War II,medicine,food, cigarettes,matches,household chemicals and other industrial sectors, the mechanization of the packaging operations; the 1950s, the packaging machine widely used common electric switches and tube for the main components of the control system to achieve the primary automation; 1960s, Electrical and optical liquid-gas technology is significantly increased in the packaging machine, machines to further expand on this basis a dedicated automated packaging line; the 1970s, the micro- electronic technology into the automation of packaging machines and packaging lines, computer control packing production process; from the 1980s to the early 1990s, in some field of packaging, computer, robot application for service, testing and management, in preparation for the over-flexible automatic packaging lines and "no" automatic packaging workshop.Actively promoted and strong co-ordination of all aspects of society, and gradually establish a packaging material, packaging, printing, packaging machinery and other production sectors, and corresponding to the research, design, education, academic, management and organization, and thus the formation of independent and complete. The packaging of light industrial system, and occupies an important place in the national economy as a whole.Based on recent years data that members of the World Packaging Alliance output value of the packaging industry accounts for about 2% of the total output value of the national economy; in which the proportion of packaging machinery, though not large, but the rapid development of an annual average of almost growing at a rate of about 10%. Put into use at the packaging machine is now more than thousand species of packaging joint machines and automated equipment has been stand-alone equate. According to the new technological revolution in the world development trend is expected to packaging materials and packaging process and packaging machinery will be closely related to obtain the breakthrough of a new step, and bring more sectors into the packaging industry.China Packaging Technology Association was established in 1980. Soon, the China National Packaging Corporation have been born. Since then, one after another in the country organized a national and international packaging machinery exhibition, seminars, also published I had the first ever "China Packaging Yearbook and other packaging technology books. All this indicates that China is creating a new packaging historical perio d.1.2中文翻译现代包装1、不断变化的需求和新的角色,回顾以往,包装所带来明显的历史性变化是可以理解的, 一个产品包装方式的给他们的销量带来的影响也是显而易见的。
英文文献全文翻译
英文文献全文翻译全文共四篇示例,供读者参考第一篇示例:LeGuin, Ursula K. (December 18, 2002). "Dancing at the Edge of the World: Thoughts on Words, Women, Places".《世界边缘的舞蹈:关于语言、女性和地方的思考》Introduction:In "Dancing at the Edge of the World," Ursula K. LeGuin explores the intersection of language, women, and places. She writes about the power of words, the role of women in society, and the importance of our connection to the places we inhabit. Through a series of essays, LeGuin invites readers to think critically about these topics and consider how they shape our understanding of the world.Chapter 1: LanguageConclusion:第二篇示例:IntroductionEnglish literature translation is an important field in the study of language and culture. The translation of English literature involves not only the linguistic translation of words or sentences but also the transfer of cultural meaning and emotional resonance. This article will discuss the challenges and techniques of translating English literature, as well as the importance of preserving the original author's voice and style in the translated text.Challenges in translating English literature第三篇示例:Title: The Importance of Translation of Full English TextsTranslation plays a crucial role in bringing different languages and cultures together. More specifically, translating full English texts into different languages allows for access to valuable information and insights that may otherwise be inaccessible to those who do not speak English. In this article, we will explore the importance of translating full English texts and the benefits it brings.第四篇示例:Abstract: This article discusses the importance of translating English literature and the challenges translators face when putting together a full-text translation. It highlights the skills and knowledge needed to accurately convey the meaning and tone of the original text while preserving its cultural and literary nuances. Through a detailed analysis of the translation process, this article emphasizes the crucial role translators play in bridging the gap between languages and making English literature accessible to a global audience.IntroductionEnglish literature is a rich and diverse field encompassing a wide range of genres, styles, and themes. From classic works by Shakespeare and Dickens to contemporary novels by authors like J.K. Rowling and Philip Pullman, English literature offers something for everyone. However, for non-English speakers, accessing and understanding these works can be a challenge. This is where translation comes in.Translation is the process of rendering a text from one language into another, while striving to preserve the original meaning, tone, and style of the original work. Translating afull-length English text requires a deep understanding of both languages, as well as a keen awareness of the cultural andhistorical context in which the work was written. Additionally, translators must possess strong writing skills in order to convey the beauty and complexity of the original text in a new language.Challenges of Full-text TranslationTranslating a full-length English text poses several challenges for translators. One of the most significant challenges is capturing the nuances and subtleties of the original work. English literature is known for its rich and layered language, with intricate wordplay, metaphors, and symbolism that can be difficult to convey in another language. Translators must carefully consider each word and phrase in order to accurately convey the author's intended meaning.Another challenge of full-text translation is maintaining the author's unique voice and style. Each writer has a distinct way of expressing themselves, and a good translator must be able to replicate this voice in the translated text. This requires a deep understanding of the author's writing style, as well as the ability to adapt it to the conventions of the target language.Additionally, translators must be mindful of the cultural and historical context of the original work. English literature is deeply rooted in the history and traditions of the English-speaking world, and translators must be aware of these influences in orderto accurately convey the author's intended message. This requires thorough research and a nuanced understanding of the social, political, and economic factors that shaped the work.Skills and Knowledge RequiredTo successfully translate a full-length English text, translators must possess a wide range of skills and knowledge. First and foremost, translators must be fluent in both the source language (English) and the target language. This includes a strong grasp of grammar, syntax, and vocabulary in both languages, as well as an understanding of the cultural and historical context of the works being translated.Translators must also have a keen eye for detail and a meticulous approach to their work. Every word, sentence, and paragraph must be carefully considered and translated with precision in order to accurately convey the meaning of the original text. This requires strong analytical skills and a deep understanding of the nuances and complexities of language.Furthermore, translators must possess strong writing skills in order to craft a compelling and engaging translation. Translating a full-length English text is not simply a matter of substituting one word for another; it requires creativity, imagination, and a deep appreciation for the beauty of language. Translators mustbe able to capture the rhythm, cadence, and tone of the original work in their translation, while also adapting it to the conventions of the target language.ConclusionIn conclusion, translating a full-length English text is a complex and challenging task that requires a high level of skill, knowledge, and creativity. Translators must possess a deep understanding of both the source and target languages, as well as the cultural and historical context of the work being translated. Through their careful and meticulous work, translators play a crucial role in making English literature accessible to a global audience, bridging the gap between languages and cultures. By preserving the beauty and complexity of the original text in their translations, translators enrich our understanding of literature and bring the works of English authors to readers around the world.。
英文文献+翻译
Characterization of production of Paclitaxel and related Taxanes in Taxus Cuspidata Densiformis suspension cultures by LC,LC/MS, and LC/MS/MSCHAPTER THEREPLANT TISSUE CULTUREⅠ. Potential of Plant cell Culture for Taxane ProductionSeveral alternative sources of paclitaxel have been identified and are currently the subjects of considerable investigation worldwide. These include the total synthesis and biosynthesis of paclitaxel, the agriculture supply of taxoids from needles of Taxus species, hemisynthesis (the attachment of a side chain to biogenetic precursors of paclitaxel such as baccatin Ⅲ or 10-deacetylbaccatin Ⅲ), fungus production, and the production of taxoids by cell and tissue culture. This reciew will concentrate only on the latter possibility.Plant tissue culture is one approach under investigation to provide large amounts and a stable supply of this compound exhibiting antineoplastic activity. A process to produce paclitaxel or paclitaxel-like compounds in cell culture has already been parented. The development of fast growing cell lines capable of producing paclitaxel would not only solve the limitations in paclitaxel supplies presently needed for clinical use, but would also help conserve the large number of trees that need to be harvested in order to isolate it. Currently, scientists and researchers have been successful in initiating fast plant growth but with limited paclitaxel production or vice versa. Therefore, it is the objective of researchers to find a method that will promote fast plant growth and also produce a large amount of paclitaxel at the same time.Ⅱ. Factors Influencing Growth Paclitaxel ContentA.Choice of Media for GrowthGamborg's (B5) and Murashige & Skoog's (MS) media seem to be superior for callus growth compared to White's (WP) medium. The major difference between these two media is that the MS medium contains 40 mM nitrate and 20mM ammonium, compared to 25mM nitrate and 2mM ammonium. Many researchers have selected the B5 medium over the MS medium for all subsequent studies, although they achieve similar results.Gamborg's B5 media was used throughout our experiments for initiation of callus cultures and suspension cultures due to successful published results. It was supplemented with 2% sucrose, 2 g/L casein hydrolysate, 2.4 mg/L picloram, and 1.8 mg/L α-naphthalene acetic acid. Agar (8 g/L) was used for solid cultures.B. Initiation of Callus CulturesPrevious work indicated that bark explants seem to be the most useful for establishing callus. The age of the tree did not appear to affect the ability to initiate callus when comparing both young and old tree materials grown on Gamborg's B5 medium supplemented with 1-2 mg/L of 2,4-dichlorophenoxyacetic acid. Callus cultures initiated and maintained in total darkness were generally pale-yellow to light brown in color. This resulted in sufficient masses of friable callus necessary for subculture within 3-4 weeks. However, the growth rate can decline substantially following the initial subculture and result in very slow-growing, brown-colored clumps of callus. It has been presumed that these brown-colored exudates are phenolic in nature and can eventually lead to cell death. This common phenomenon is totally random and unpredictable. Once this phenomenon has been triggered, the cells could not be saved by placing them in fresh media. However, adding polyvinylpyrrolidone to the culture media can help keep the cells alive and growing. Our experience with callus initiationwas similar to those studies.Our studies have found that callus which initiated early (usually within 2 weeks ) frequently did not proliferate when subcultured and turned brown and necrotic. In contrast, calli which developed from 4 weeks to 4 months after explants were fist placed on initiation media were able to be continuously subcultured when transferred at 1-2 month intervals. The presence of the survival of callus after subsequent subculturing. The relationship between paclitaxel concentration and callus initiation, however, has not been clarified.C. Effect of SugarSucrose is the preferred carbon source for growth in plant cell cultures, although the presence of more rapidly metabolized sugar such as glucose favors fast growth. Other sugars such as lactose, galactose, glucose, and fructose also support cell growth to some extent. On the other hand, sugar alcohols such as mannitol and sorbital which are generally used to raise the sugars added play a major role in the production of paclitaxel. In general, raising the initial sugar levels lead to an increase of secondary metabolite production. High initial levels of sugar increase the osmotic potential, although the role of osmotic pressure on the synthesis of secondary metabolites is not cleat. Kim and colleagues have shown that the highest level of paclitaxel was obtained with fructosel. The optimum concentration of each sugar for paclitaxel production was found to be the same at 6% in all cases. Wickremesinhe and Arteca have provided additional support that fructose is the most effective for paclitaxel production. However, other combinations of sugars such as sucrose combined with glucose also increased paclitaxel production.The presence of extracellular invertase activity and rapid extracellular sucrose hydrolysis has been observed in many cell cultures. These reports suggest that cells secrete or possess on their surface excess amounts of invertase, which result in the hydrolysis of sucrose at a much faster rate. The hydrolysis of sucrose coupled with the rapid utilization of fructose in the medium during the latter period of cell growth. This period of increased fructose availability coincided with the faster growth phase of the cells.D. Effect of Picloram and Methyl JasmonatePicloram (4-amino-3.5.6-trichloropicolinic acid) increases growth rate while methyl jasmonate has been reported to be an effective elicitor in the production of paclitaxel and other taxanes. However, little is known about the mechanisms or pathways that stimulate these secondary metabolites.Picloram had been used by Furmanowa and co-workers and Ketchum and Gibson but no details on the effect of picloram on growth rates were given. Furmanowa and hid colleagues observed growth of callus both in the presence and absence of light. The callus grew best in the dark showing a 9.3 fold increase, whereas there was only a 2-4 fold increase in the presence of light. Without picloram, callus growth was 0.9 fold. Unfortunately,this auxin had no effect on taxane production and the high callus growth rate was very unstable.Jasmonates exhibit various morphological and physiological activities when applied exogenously to plants. They induce transcriptional activation of genes involved in the formation of secondary metabolites. Methyl jasmonate was shown to stimulate paclitaxel and cephalomannine (taxane derivative) production in callus and suspension cultures. However, taxane production was best with White's medium compared to Gamborg's B5 medium. This may be due to the reduced concentration of potassium nitrate and a lack of ammonium sulfate with White's medium.E. Effect of Copper Sulfate and Mercuric ChlorideMetal ions have shown to play significant roles in altering the expression of secondary metabolic pathways in plant cell culture. Secondary metabolites,such as furano-terpenes, have been production by treatment of sweet potato root tissue with mercuric chloride. The results for copper sulfate, however, have not been reported. F. Growth Kinetics and Paclitaxel ProductionLow yields of paclitaxel may be attributed to the kinetics of taxane production that is not fully understood. Many reports stated inconclusive results on the kinetics of taxane production. More studies are needed in order to quantitate the taxane production. According to Nett-Fetto, the maximum instantaneous rate of paclitaxel production occurred at the third week upon further incubation. The paclitaxel level either declined or was not expected to increase upon further incubation. Paclitaxel production was very sensitive to slight variations in culture conditions. Due to this sensitivity, cell maintenance conditions, especially initial cell density, length of subculture interval, and temperature must be maintained as possible.Recently, Byun and co-workers have made a very detailed study on the kinetics of cell growth and taxane production. In their investigation, it was observed that the highest cell weight occurred at day 7 after inoculation. Similarly, the maximum concentration for 10-deacetyl baccatin Ⅲ and baccatin Ⅲ were detected at days 5 and 7, respectively. This result indicated that they are metabolic intermediates of paclitaxel. However, paclitaxel's maximum concentration was detected at day 22 but gradually declined. Byun and his colleagues suggested that paxlitaxel could be a metabolic intermediate like 10-deacetyl baccatin Ⅲ and baccatin Ⅲ or that pacliltaxel could be decomposed due to cellular morphological changes or DNA degradation characteristic of cell death.Pedtchanker's group also studied the kinetics of paclitaxel production by comparing the suspension cultures in shake flasks and Wilson-type reactors where bubbled air provided agitation and mixing. It was concluded that these cultures of Taxus cuspidata produced high levels of paclitaxel within three weeks (1.1 mg/L per day ). It was also determined that both cultures of the shake flask and Wilson-type reactor produced similar paclitaxel content. However, the Wilson-type reactor had a more rapid uptake of the nutrients (i.e. sugars, phosphate, calcium, and nitrate). This was probably due to the presence of the growth ring in the Wilson reactor. Therefor, the growth rate for the cultures from the Wilson reactor was only 135 mg./L while the shake flasks grew to 310 mg/L in three weeks.In retrospect, strictly controlled culture conditions are essential to consistent production and yield. Slight alterations in media formulations can have significant effects upon the physiology of cells, thereby affecting growth and product formation. All of the manipulations that affect growth and production of plant cells must be carefully integrated and controlled in order to maintain cell viability and stability.利用LC,LC/MS和LC/MS/MS悬浮培养生产紫杉醇及邓西佛米斯红豆杉中相关紫杉醇类的特征描述第三章植物组织培养Ⅰ.利用植物细胞培养生产紫杉的可能性紫杉醇的几个备选的来源已被确定,而且目前是全球大量调查的主题。
液压系统外文文献翻译中英文
外文文献翻译(含:英文原文及中文译文)英文原文Hydraulic systemW Arnold1 IntroductionThe hydraulic station is called a hydraulic pump station and is an independent hydraulic device. It is step by step to supply oil. And control the direction of hydraulic oil flow, pressure and flow, suitable for the host and hydraulic equipment can be separated on the various hydraulic machinery.After the purchase, the user only needs to connect the hydraulic station and the actuator (hydraulic or oil motor) on the mainframe with different tubings. The hydraulic machine can realize various specified actions and working cycles.The hydraulic station is a combination of manifolds, pump units or valve assemblies, electrical boxes, and tank electrical boxes. Each part function is:The pump unit is equipped with a motor and an oil pump, which is the power source of the hydraulic station and can convert mechanical energy into hydraulic oil pressure energy.V alve combination - its plate valve is mounted on the vertical plate, and the rear plate is connected with the same function as the manifold.Oil manifolds - assembled from hydraulic valves and channel bodies. It regulates hydraulic oil pressure, direction and flow.Box--a semi-closed container for plate welding. It is also equipped with an oil screen, an air filter, etc., which is used for cooling and filtering of oil and oil.Electrical box - divided into two types: one is to set the external lead terminal board; one is equipped with a full set of control appliances.The working principle of the hydraulic station: The motor drives the oil pump to rotate, then the pump sucks oil from the oil tank and supplies oil, converts the mechanical energy into hydraulic pressure energy, and the hydraulic oil passes through the manifold (or valve assembly) to adjust the direction, pressure and flow and then passes through the external tube. The way to the hydraulic cylinder or oil motor in the hydraulic machinery, so as to control the direction of the hydraulic motor, the strength of the speed and speed, to promote all kinds of hydraulic machinery to do work.(1) Development history of hydraulic pressureThe development history of hydraulics (including hydraulic power, the same below), pneumatics, and seals industry in China can be roughly divided into three stages, namely: the starting stage in the early 1950s to the early 60s; and the professional in the 60s and 70s. The growth stage of the production system; the 80-90's is a stage of rapid development. Among them, the hydraulic industry began in the early 1950s with thedevelopment of hydraulic machines such as Grinding Machines, broaching machines, and profiling lathes, which were produced by the machine tool industry. The hydraulic components were produced by the hydraulic workshop in the machine tool factory, and were produced for self use. After entering the 1960s, the application of hydraulic technology was gradually promoted from the machine tool to the agricultural machinery and engineering machinery. The original hydraulic workshop attached to the main engine plant was independent and became a professional manufacturer of hydraulic components. In the late 1960s and early 1970s, with the continuous development of mechanization of production, particularly in the provision of highly efficient and automated equipment for the second automobile manufacturing plant, the hydraulic component manufacturing industry witnessed rapid development. The batch of small and medium-sized enterprises also began to become specialized manufacturers of hydraulic parts. In 1968, the annual output of hydraulic components in China was close to 200,000 pieces. In 1973, in the fields of machine tools, agricultural machinery, construction machinery and other industries, the professional factory for the production of hydraulic parts has grown to over 100, and its annual output exceeds 1 million pieces. Such an independent hydraulic component manufacturing industry has taken shape. At this time, the hydraulic product has evolved from the original imitation Su product intoa combination of imported technology and self-designed products. The pressure has been developed towards medium and high pressures, and electro-hydraulic servo valves and systems have been developed. The application of hydraulics has been further expanded. The pneumatic industry started a few years later than hydraulics, and it was only in 1967 that it began to establish a professional pneumatic components factory. Pneumatic components began to be manufactured and sold as commodities. Its sealing industry including rubber seals, flexible graphite seals, and mechanical seals started from the production of common O-rings, oil seals, and other extruded rubber seals and asbestos seal products in the early 1950s. In the early 1960s, it began to develop and produce flexible products. Graphite seals and mechanical seals and other products. In the 1970s, a batch of batches of professional production plants began to be established one after another in the systems of the former Ministry of Combustion, the Ministry of Agriculture, and the Ministry of Agricultural Machinery, formally forming the industry, which laid the foundation for the development of the seal industry.In the 1980s, under the guidance of the national policy of reform and opening up, with the continuous development of the machinery industry, the contradiction between the basic components lags behind the host computer has become increasingly prominent and caused the attention of all relevant departments. To this end, the former Ministry of Machinesestablished the General Infrastructure Industry Bureau in 1982, and unified the original pneumatic, hydraulic, and seal specialties that were scattered in the industries of machine tools, agricultural machinery, and construction machinery, etc. The management of a piece of office, so that the industry in the planning, investment, the introduction of technology and scientific research and development and other aspects of the basic parts of the bureau's guidance and support. This has entered a period of rapid development, it has introduced more than 60 foreign advanced technology, of which more than 40 hydraulic, pneumatic 7, after digestion and absorption and technological transformation, are now mass production, and has become the industry's leading products . In recent years, the industry has intensified its technological transformation. From 1991 to 1998, the total investment of national, local, and corporate self-raised funds totaled about 2 billion yuan, of which more than 1.6 billion were hydraulic. After continuous technological transformation and technological breakthroughs, the technical level of a group of major enterprises has been further improved, and technological equipment has also been greatly improved, laying a good foundation for forming a high starting point, specialization, and mass production. In recent years, under the guidance of the principle of common development of multiple ownership systems in the country, various small and medium-sized enterprises with different ownership have rapidly emerged and haveshown great vitality. With the further opening up of the country, foreign-funded enterprises have developed rapidly, which plays an important role in raising industry standards and expanding exports. So far China has established joint ventures with famous manufacturers in the United States, Germany, Japan and other countries or directly established piston pumps/motors, planetary speed reducers, hydraulic control valves, steering gears, hydraulic systems, hydrostatic transmissions, and hydraulic components. The company has more than 50 manufacturing enterprises such as castings, pneumatic control valves, cylinders, gas processing triplets, rubber seals, and mechanical seals, and has attracted more than 200 million U.S. dollars in foreign capital.(2) Current statusBasic profileAfter more than 40 years of hard work, China's hydraulics, pneumatics and seals industry has formed a complete industrial system with a certain level of production capacity and technical level. According to the statistics of the third n ational industrial census in 1995, China’s state-owned, privately-owned, cooperative, village-run, individual, and “funded enterprises” have annual sales income of more than 1 million yuan in hydraulic, pneumatic, and seal industrial townships and above. There are a total of more than 1,300 companies, including about 700 hydraulics, and about 300 pneumatic and sealing parts. According to thestatistics of the international industry in 1996, the total output value of the hydraulic industry in China was about 2.448 billion yuan, accounting for the 6th in the world; the total output value of the pneumatic industry was about 419 million yuan, accounting for the world’s10 people.2. Current supply and demand profileWith the introduction of technology, independent development and technological transformation, the technical level of the first batch of high-pressure plunger pumps, vane pumps, gear pumps, general hydraulic valves, oil cylinders, oil-free pneumatic components and various types of seals has become remarkable. Improve, and can be stable mass production, provide guarantees for all types of host to improve product quality. In addition, certain achievements have also been made in the aspects of CAD, pollution control, and proportional servo technology for hydraulic pneumatic components and systems, and have been used for production. So far, the hydraulic, pneumatic and seal products have a total of about 3,000 varieties and more than 23,000 specifications. Among them, there are about 1,200 types of hydraulic pressure, more than 10,000 specifications (including 60 types of hydrodynamic products, 500 specifications); about 1350 types of pneumatic, more than 8,000 specifications; there are also 350 types of rubber seals, more than 5000 The specifications are now basically able to adapt to the general needs ofvarious types of mainframe products. The matching rate for major equipment sets can reach more than 60%, and a small amount of exports has started.In 1998, the domestic production of hydraulic components was 4.8 million pieces, with sales of about 2.8 billion yuan (of which mechanical systems accounted for 70%); output of pneumatic components was 3.6 million pieces, and sales were about 550 million yuan (including mechanical systems accounting for about 60%) The production of seals is about 800 million pieces, and the sales volume is about 1 billion yuan (including about 50% of mechanical systems). According to the statistics of the annual report of the China Hydraulic and Pneumatic Sealing Industry Association in 1998, the production and sales rate of hydraulic products was 97.5% (101% of hydraulic power), 95.9% of air pressure, and 98.7% of seal. This fully reflects the basic convergence of production and sales.Although China's hydraulic, pneumatic and sealing industries have made great progress, there are still many gaps compared with the development needs of the mainframe and the world's advanced level, which are mainly reflected in the variety, performance and reliability of products. . Take hydraulic products as an example, the product varieties are only 1/3 of the foreign country, and the life expectancy is 1/2 of that of foreign countries. In order to meet the needs of key hosts, imported hosts, and majortechnical equipment, China has a large number of imported hydraulic, pneumatic, and sealing products every year. According to customs statistics and relevant data analysis, in 1998, the import volume of hydraulic, pneumatic and seal products was about 200 million U.S. dollars, of which the hydraulic pressure was about 140 million U.S. dollars, the pneumatics were 30 million U.S. dollars, and the seal was about 0.3 billion U.S. dollars. The year is slightly lower. In terms of amount, the current domestic market share of imported products is about 30%. In 1998, the total demand for hydraulic parts in the domestic market was about 6 million pieces, and the total sales volume was 4 billion yuan; the total demand for pneumatic parts was about 5 million pieces, and the total sales volume was over 700 million yuan; the total demand for seals was about 1.1 billion yuan. Pieces, total sales of about 1.3 billion yuan. (3) Future developments1. The main factors affecting development(1) The company's product development capability is not strong, and the level and speed of technology development can not fully meet the current needs for advanced mainframe products, major technical equipment and imported equipment and maintenance;(2) Many companies have lagged behind in manufacturing process, equipment level and management level, and their sense of quality is not strong, resulting in low level of product performance, unstable quality,poor reliability, and insufficiency of service, and lack of user satisfaction. And trusted branded products;(3) The degree of professional specialization in the industry is low, the power is scattered, the duplication of the low level is serious, the product convergence between the region and the enterprise leads to blind competition, and the prices are reduced each other, thus the efficiency of the enterprise is reduced, the funds are lacking, and the turnover is difficult. Insufficient investment in development and technological transformation has severely restricted the overall level of the industry and its competitive strength.(4) When the degree of internationalization of the domestic market is increasing, foreign companies have gradually entered the Chinese market to participate in competition, coupled with the rise of domestic private, cooperative, foreign-funded, and individual enterprises, resulting in increasing impact on state-owned enterprises. .2. Development trendWith the continuous deepening of the socialist market economy, the relationship between supply and demand in the hydraulic, pneumatic and sealed products has undergone major changes. The seller market characterized by “shortage” has basically become a buyer’s market characterized by “structured surplus”. Replaced by. From the perspective of overall capacity, it is already in a trend of oversupply, and in particular,general low-grade hydraulic, pneumatic and seals are generally oversupply; and like high-tech products with high technological content and high value and high value-added products that are urgently needed by the host, Can not meet the needs of the market, can only rely on imports. After China's entry into the WTO, its impact may be greater. Therefore, during the “10th Five-Y ear Plan” period, the growth of the industry’s output value must not only rely on the growth of quantity. Instead, it should focus on the structural contradiction of the industry and intensify efforts to adjust the industrial structure and product structure. It should be based on the improvement of quality. Product technology upgrades in order to adapt to and stimulate market demand, and seek greater development.2. Hydraulic application on power slide(1) Introduction of Power Sliding TableUsing the binding force curve diagram and the state space analysis method to analyze and study the sliding effect and the smoothness of the sliding table of the combined machine tool, the dynamics of the hydraulic drive system of the sliding table—the self-regulating back pressure regulating system are established. mathematical model. Through the digital simulation system of the computer, the causes and main influencing factors of the slide impact and the motion instability are analyzed. What kind of conclusions can be drawn from those, if we canreasonably design the structural dimensions of hydraulic cylinders and self-regulating back pressure regulators ——The symbols used in the text are as follows:s 1 - flow source, that is, the flow rate of the governor valve outlet;S el —— sliding friction of the sliding table;R - the equivalent viscous friction coefficient of the slide;I 1 - quality of slides and cylinders;12 - self-adjusting back pressure valve core quality;C 1, c 2 - liquid volume without cylinder chamber and rod chamber;C 2 - Self-adjusting back pressure valve spring compliance;R 1, R2 - Self-adjusting back pressure valve damping orifice fluid resistance;R 9 - Self-adjusting back pressure valve valve fluid resistance;S e2——initial pre-tightening force of self-adjusting back pressure valve spring;I 4, I5 - Equivalent liquid sense of the pipeline;C 5, C 6 - equivalent liquid capacity of the pipeline;R 5, R7 - Equivalent liquid resistance of the pipeline;V 3, V4 - cylinder rodless cavity and rod cavity volume;P 3, P4—pressure of the rodless cavity and rod cavity of the cylinder;F - the slide bears the load;V - speed of slide motion;In this paper, the power bond diagram and the state space splitting method are used to establish the system's motion mathematical model, and the dynamic characteristics of the slide table can be significantly improved.In the normal operation of the combined machine tool, the magnitude of the speed of the slide, its direction and the load changes it undergoes will affect its performance in varying degrees. Especially in the process of work-in-process, the unsteady movement caused by the advancing of the load on the slide table and the cyclical change of the load will affect the surface quality of the workpiece to be machined. In severe cases, the tool will break. According to the requirements of the Dalian Machine Tool Plant, the author used the binding force curve diagram and the state space analysis method to establish a dynamic mathematical model of a self-adjusting back pressure and speed adjustment system for the new hydraulic drive system of the combined machine tool slide. In order to improve the dynamic characteristics of the sliding table, it is necessary to analyze the causes and main influencing factors of the impetus and movement of the sliding table. However, it must pass the computer's digital simulation and the final results obtained from the research.(2) Dynamic Mathematical ModelThe working principle diagram of the self-adjusting back pressure speedregulation system of the combined machine tool slide hydraulic drive system is shown in the figure. This system is used to complete the work-cycle-stop-rewind. When the sliding table is working, the three-position four-way reversing valve is in the illustrated position. The oil supply pressure of the oil pump will remain approximately constant under the effective action of the overflow valve, and the oil flow passes through the reversing valve and adjusts the speed. The valve enters the rodless chamber of the cylinder to push the slide forward. At the same time, the pressurized oil discharged from the rod chamber of the cylinder will flow back to the tank through the self-regulating back pressure valve and the reversing valve. During this process, there was no change in the operating status of both the one-way valve and the relief valve. The complex and nonlinear system of the hydraulic drive system of the self-adjusting back pressure governor system is a kind of self-adjusting back-pressure governor system. To facilitate the study of its dynamic characteristics, a simple and reasonable dynamic mathematical model that only considers the main influencing factors is established. Especially important [1][2]. From the theoretical analysis and the experimental study, we can see that the system process time is much longer than the process time of the speed control valve. When the effective pressure bearing area of the rodless cavity of the fuel tank is large, the flow rate at the outlet of the speed control valve is instantaneous. The overshoot is reflected in thesmall change in speed of the slide motion [2]. In order to further broaden and deeply study the dynamic characteristics of the system so that the research work can be effectively performed on a miniature computer, this article will further simplify the original model [2], assuming that the speed control valve is output during the entire system pass. When the flow is constant, this is considered to be the source of the flow. The schematic diagram of the dynamic model structure of this system is shown in Fig. 2. It consists of a cylinder, a sliding table, a self-adjusting back pressure valve, and a connecting pipe.The power bond graph is a power flow graph. It is based on the transmission mode of the system energy, based on the actual structure, and uses the centralized parameters to represent the role of the subsystems abstractly as a resistive element R, a perceptual element I, and a capacitive element. Three kinds of role of C. Using this method, the physical concept of modeling is clear, and combined with the state-space analysis method, the linear system can be described and analyzed more accurately. This method is an effective method to study the dynamic characteristics of complex nonlinear systems in the time domain. According to the main characteristics of each component of the self-adjusting back pressure control system and the modeling rules [1], the power bond diagram of the system is obtained. The upper half of each key in the figure represents the power flow. The two variables that makeup the power are the force variables (oil pressure P and force F) and the flow variables (flow q and velocity v). The O node indicates that the system is connected in parallel, and the force variables on each key are equal and the sum of the flow variables is zero; 1 The nodes represent the series connection in the system, the flow variables on each key are equal and the sum of the force variables is Zero. TF denotes a transformer between different energy forms. The TF subscripted letter represents the conversion ratio of the flow variable or the force variable. The short bar on the key indicates the causal relationship between the two variables on the key. The full arrow indicates the control relationship. There are integral or differential relationships between the force and flow variables of the capacitive and perceptual elements in the three types of action elements. Therefore, a complex nonlinear equation of state with nine state variables can be derived from Fig. 3 . In this paper, the research on the dynamic characteristics of the sliding table starts from the two aspects of the slide's hedging and the smoothness of the motion. The fourth-order fixed-length Runge-Kutta is used for digital simulation on the IBM-PC microcomputer.(3) Slide advanceThe swaying phenomenon of the slide table is caused by the sudden disappearance of the load acting on the slide table (such as drilling work conditions). In this process, the table load F, the moving speed V, and thepressure in the two chambers of the cylinder P3 and P4 can be seen from the simulation results in Fig. 4. When the sliding table moves at a uniform speed under the load, the oil pressure in the rodless cavity of the oil cylinder is high, and a large amount of energy is accumulated in the oil. When the load suddenly disappears, the oil pressure of the cavity is rapidly reduced, and the oil is rapidly reduced. When the high-pressure state is transferred to the low-pressure state, a lot of energy is released to the system, resulting in a high-speed forward impact of the slide. However, the front slide of the sliding table causes the pressure in the rod cavity of the oil cylinder to cause the back pressure to rise, thereby consuming part of the energy in the system, which has a certain effect on the kicking of the slide table. We should see that in the studied system, the inlet pressure of the self-adjusting back pressure valve is subject to the comprehensive effect of the two-chamber oil pressure of the oil cylinder. When the load suddenly disappears, the pressure of the self-adjusting back pressure valve rapidly rises and stably exceeds the initial back pressure value. It can be seen from the figure that self-adjusting back pressure in the speed control system when the load disappears, the back pressure of the cylinder rises more than the traditional speed control system, so the oil in the rod cavity of the cylinder absorbs more energy, resulting in the amount of forward momentum of the slide It will be about 20% smaller than traditionalspeed control systems. It can be seen from this that the use of self-adjusting back-gear speed control system as a drive system slider has good characteristics in suppressing the forward punch, in which the self-adjusting back pressure valve plays a very large role.(4) The smoothness of the slideWhen the load acting on the slide changes periodically (such as in the case of milling), the speed of the slide will have to fluctuate. In order to ensure the processing quality requirements, it must reduce its speed fluctuation range as much as possible. From the perspective of the convenience of the discussion of the problem, assume that the load changes according to a sine wave law, and the resulting digital simulation results are shown in Figure 5. From this we can see that this system has the same variation rules and very close numerical values as the conventional speed control system. The reason is that when the change of the load is not large, the pressure in the two chambers of the fuel tank will not have a large change, which will eventually lead to the self-regulating back pressure valve not showing its effect clearly.(5) Improvement measuresThe results of the research show that the dynamic performance of a sliding table with self-regulating back pressure control system as a drive system is better than that of a traditional speed control system. To reduce the amount of kick in the slide, it is necessary to rapidly increase the backpressure of the rod cavity when the load disappears. To increase the smoothness of the sliding table, it is necessary to increase the rigidity of the system. The main measure is to reduce the volume of oil. From the system structure, it is known that the cylinder has a large volume between the rod cavity and the oil discharge pipe, as shown in Fig. 6a. Its existence in terms of delay and attenuation of the self-regulating back pressure valve function, on the other hand, also reduces the rigidity of the system, it will limit the further improvement of the propulsion characteristics and the smoothness of the motion. Thus, improving the dynamic characteristics of the sliding table can be handled by two methods: changing the cylinder volume or changing the size of the self-regulating back pressure valve. Through the simulation calculation of the structural parameters of the system and the comparison of the results, it can be concluded that the ratio of the volume V4 between the rod cavity and the oil discharge pipe to the volume V3 between the rodless cavity and the oil inlet pipe is changed from 5.5 to 5.5. At 1 oclock, as shown in the figure, the diameter of the bottom end of the self-adjusting back pressure valve is increased from the original 10mm to 13mm, and the length of the damper triangle groove is reduced from the original lmm to 0.7mm, which will enable the front of the slide table. The impulse is reduced by 30%, the transition time is obviously shortened, and the smoothness of the slide motion will also be greatly improved.中文译文液压系统W Arnold1. 绪论液压站称液压泵站,是独立的液压装置。
英文文献原文及对应翻译
Adsorption char acter istics of copper , lead, zinc and cadmium ions by tourmaline(环境科学学报英文版) 电气石对铜、铅、锌、镉离子的吸附特性JIANG Kan1,*, SUN Tie-heng1,2 , SUN Li-na2, LI Hai-bo2(1. School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China. jiangkan522@; 2. Key Laboratory of Environmental Engineering of Shenyang University, Shenyang 110041, China)摘要:本文研究了电气石对Cu2+、Pb2+、Zn2+和Cd2+的吸附特性,建立了吸附平衡方程。
研究四种金属离子的吸附等温线以及朗缪尔方程。
结果表明电气石能有效地去除水溶液中的重金属且具有选择性:Pb2+> Cu2+> Cd2+> Zn2+。
电气石对金属离子吸附量随着介质中金属离子的初始浓度的增加而增加。
电气石也可以增加金属溶液的pH值;发现电气石对Cu2+、Pb2+、Zn2+和Cd2+的最大吸附量为78.86、154.08、67.25和66.67mg/g;温度在25-55℃对电气石的吸附量影响很小。
此外研究了Cu2+、Pb2+、Zn2+和Cd2+的竞争吸附。
同时观察到电气石对单一金属离子的吸附能力为Pb>Cu>Zn>Cd,在两种金属系统中抑制支配地位是Pb>Cu,Pb>Zn,Pb>Cd,Cu>Zn,Cu>Cd,和Cd>Zn。
关键字:吸附;重金属含量;朗缪尔等温线;电气石介绍重金属是来自不同行业排出的废水,如电镀,金属表面处理,纺织,蓄电池,矿山,陶瓷,玻璃。
经济学毕业论文英文文献及翻译1
The green barrier to free tradeC. P. ChandrasekharJayati GhoshAs the March 31 deadline for completing the "modalities" stage of the proposed new round of negotiations on global agricultural trade nears, hopes of an agreement are increasingly waning. In this edition of Macroscan, C. P. Chandrasekhar and Jayati Ghosh examine the factors and the players constraining the realisation of such an agreement.AT THE END of the latest round of meetings of the agricultural negotiations committee of the WTO, the optimism that negotiators would meet the March 31 deadline for working out numerical targets, formulas and other "modalities" through which countries can frame their liberalisation commitments in a new full-fledged round of trade negotiations has almost disappeared. That target was important for two reasons.First, it is now becoming clear, that even more than was true during the Uruguay Round, forging an agreement in the agricultural area is bound to prove extremely difficult.Progress in the agricultural negotiations was key to persuading the unconvinced that a new `Doha Round' of trade negotiations is useful and feasible.Second, the Doha declaration made agricultural negotiations one part of a `single undertaking' to be completed by January 1, 2005. That is, in a take `all-or-nothing' scheme, countries had to arrive at, and be bound by, agreements in all areas in which negotiations were to be initiated in the new round. This means that if agreement is not worked out with regard to agriculture, there would be no change in the multilateral trade regime governing industry, services or related areas and no progress in new areas, such as competition policy, foreign investment and public procurement, all of which are crucial to the economic agenda of the developed countries.The factors making agriculture the sticking point on this occasion are numerous. As in the last Round, there is little agreement among the developed countries themselves on the appropriate shape of the global agricultural trade regime.There are substantial differences in the agenda of the US, the EU and the developed countries within the Cairns group of agricultural exporters. When the rich and the powerful disagree, a global consensus is not easy to come by.But that is not all. Even if an agreement is stitched up between the rich nations, through manoeuvres such as the Blair House accord, getting the rest of the world to go along would be more difficult this time.This is because the outcomes in the agricultural trade area since the implementation of the Uruguay Round (UR) Agreement on Agriculture (AoA) began have fallen far short of expectations. In the course of Round, advocates of the UR regime had promised global production adjustments that would increase the value of world agricultural trade and an increase in developing country share of such trade.As Chart 1 shows, global production volumes continued to rise after 1994 when the implementation of the Uruguay Round began, with signs of tapering off only in 2000 and 2001. As is widely known, this increase in production occurred in the developed countries as well.Not surprisingly, therefore, the volume of world trade continued to rise as well after 1994 (Chart 2). The real shift occurred in agricultural prices which, after some buoyancy between 1993and 1995, have declined thereafter, and particularly sharply after 1997. It is this decline in unit values that resulted in a situation where the value of world trade stagnated and then declined after 1995, when the implementation of the Uruguay Round began.As Table 1 shows, there was a sharp fall in the rate of growth of global agricultural trade between the second half of the 1980s and the 1990s, with the decline in growth in the 1990s being due to the particularly poor performance during the 1998 to 2001 period.Price declines and stagnation in agricultural trade values in the wake of the UR Agreement on Agriculture were accompanied and partly influenced by the persisting regionalisation of world agricultural trade.The foci of such regionalisation were Western Europe and Asia, with 32 and 11 per cent of global agricultural trade being intra-Western European and intra-Asian trade respectively (Chart 3). What is noteworthy, however, is that agricultural exports accounted for a much higher share of both merchandise and primary products trade in North America and Western Europe (besides Latin America and Africa) than it did for Asia.Thus, despite being the developed regions of the world, agricultural production and exports were important influences on the economic performance of North America and Western Europe.It is, therefore, not surprising that Europe is keen on maintaining its agricultural sector through protection, while the US is keen on expanding its role in world agricultural markets by subsidising its own farmers and forcing other countries to open up their markets. The problem is that the US has been more successful in prising open developing country markets than the large EU market.Thus, out of $104 billion worth of exports from North America in 2001, $34 billion went to Asia and $15 billion to Latin America, whereas exports to Europe amounted to $14 billion.The Cairns group of exporting countries (Argentina, Australia, Bolivia, Brazil, Canada, Chile, Colombia, Costa Rica, Guatemala, Indonesia, Malaysia, New Zealand, Paraguay, the Philippines, South Africa, Thailand and Uruguay), for some of whom at least agricultural exports are extremely important, want world market to be freed of protection as well as the surpluses that result from huge domestic support in the US and the EC.We must note that $35 billion of the $63 billion of exports from Latin America went to the US and the EU. More open markets and less domestic support in those destinations is, therefore, crucial for the region.The fact that Europe has been successful in its effort at retaining its agricultural space with the help of a Common Agricultural Policy that both supports and subsidises its agricultural producers is clear from Chart 4, which shows that intra-EC trade which accounted for 74 per cent of EU exports in 1990, continued to account for 73 per cent of total EU exports in 1995 and 2001.But North America, with far fewer countries in its fold, has also been quite insular. Close to a third of North American exports are inter-regional. Little has changed since the Uruguay Round Agreement on Agriculture.It is widely accepted that three sets of actors account for this failure of the AoA:First, in order to push through an agreement when there were signs that the Uruguay Round was faltering, the liberalisation of agricultural trade in the developed countries was not pushed far enough;Second, is the ability to use "loopholes", especially those in the form of inadequately well-defined Green and Blue Box measures, in the AoA, to continue to support and protect farmers on the grounds that such support was non-trade distorting; andFinally, there are violations of even the lax UR rules in the course of implementation, which have been aided by the failure of the agreement to ensure transparency in implementation.Not surprisingly, some countries, especially the Cairns group of exporting countries, have proposed an ambitious agenda of liberalisation in the agricultural area.Tariffs are to be reduced sharply, using the "Swiss formula", which would ensure that the proportionate reduction in the tariffs imposed by a country would be larger, the higher is the prevailing bound or applied tariff in that country.中文翻译:题目:自由贸易中的绿色壁垒作者:C. P. Chandrasekhar 、Jayati Ghosh在A完自由化的承诺在其最新一轮会议的农业谈判委员会,世界贸易组织,乐观地认为,谈判的框架将在3月31日最后期限为制定数字指标,公式和其他“方式,哪些国家可以”通过新的全面谈判回合贸易几乎已经消失。
数据采集外文文献翻译中英文
数据采集外文文献翻译(含:英文原文及中文译文)文献出处:Txomin Nieva. DATA ACQUISITION SYSTEMS [J]. Computers in Industry, 2013, 4(2):215-237.英文原文DATA ACQUISITION SYSTEMSTxomin NievaData acquisition systems, as the name implies, are products and/or processes used to collect information to document or analyze some phenomenon. In the simplest form, a technician logging the temperature of an oven on a piece of paper is performing data acquisition. As technology has progressed, this type of process has been simplified and made more accurate, versatile, and reliable through electronic equipment. Equipment ranges from simple recorders to sophisticated computer systems. Data acquisition products serve as a focal point in a system, tying together a wide variety of products, such as sensors that indicate temperature, flow, level, or pressure. Some common data acquisition terms are shown below.Data collection technology has made great progress in the past 30 to 40 years. For example, 40 years ago, in a well-known college laboratory, the device used to track temperature rises in bronze made of helium was composed of thermocouples, relays, interrogators, a bundle of papers, anda pencil.Today's university students are likely to automatically process and analyze data on PCs. There are many ways you can choose to collect data. The choice of which method to use depends on many factors, including the complexity of the task, the speed and accuracy you need, the evidence you want, and more. Whether simple or complex, the data acquisition system can operate and play its role.The old way of using pencils and papers is still feasible for some situations, and it is cheap, easy to obtain, quick and easy to start. All you need is to capture multiple channels of digital information (DMM) and start recording data by hand.Unfortunately, this method is prone to errors, slower acquisition of data, and requires too much human analysis. In addition, it can only collect data in a single channel; but when you use a multi-channel DMM, the system will soon become very bulky and clumsy. Accuracy depends on the level of the writer, and you may need to scale it yourself. For example, if the DMM is not equipped with a sensor that handles temperature, the old one needs to start looking for a proportion. Given these limitations, it is an acceptable method only if you need to implement a rapid experiment.Modern versions of the strip chart recorder allow you to retrieve data from multiple inputs. They provide long-term paper records of databecause the data is in graphic format and they are easy to collect data on site. Once a bar chart recorder has been set up, most recorders have enough internal intelligence to operate without an operator or computer. The disadvantages are the lack of flexibility and the relative low precision, often limited to a percentage point. You can clearly feel that there is only a small change with the pen. In the long-term monitoring of the multi-channel, the recorders can play a very good role, in addition, their value is limited. For example, they cannot interact with other devices. Other concerns are the maintenance of pens and paper, the supply of paper and the storage of data. The most important is the abuse and waste of paper. However, recorders are fairly easy to set up and operate, providing a permanent record of data for quick and easy analysis.Some benchtop DMMs offer selectable scanning capabilities. The back of the instrument has a slot to receive a scanner card that can be multiplexed for more inputs, typically 8 to 10 channels of mux. This is inherently limited in the front panel of the instrument. Its flexibility is also limited because it cannot exceed the number of available channels. External PCs usually handle data acquisition and analysis.The PC plug-in card is a single-board measurement system that uses the ISA or PCI bus to expand the slot in the PC. They often have a reading rate of up to 1000 per second. 8 to 16 channels are common, and the collected data is stored directly in the computer and then analyzed.Because the card is essentially a part of the computer, it is easy to establish the test. PC-cards are also relatively inexpensive, partly because they have since been hosted by PCs to provide energy, mechanical accessories, and user interfaces. Data collection optionsOn the downside, the PC plug-in cards often have a 12-word capacity, so you can't detect small changes in the input signal. In addition, the electronic environment within the PC is often susceptible to noise, high clock rates, and bus noise. The electronic contacts limit the accuracy of the PC card. These plug-in cards also measure a range of voltages. To measure other input signals, such as voltage, temperature, and resistance, you may need some external signal monitoring devices. Other considerations include complex calibrations and overall system costs, especially if you need to purchase additional signal monitoring devices or adapt the PC card to the card. Take this into account. If your needs change within the capabilities and limitations of the card, the PC plug-in card provides an attractive method for data collection.Data electronic recorders are typical stand-alone instruments that, once equipped with them, enable the measurement, recording, and display of data without the involvement of an operator or computer. They can handle multiple signal inputs, sometimes up to 120 channels. Accuracy rivals unrivalled desktop DMMs because it operates within a 22 word, 0.004 percent accuracy range. Some data electronic automatic recordershave the ability to measure proportionally, the inspection result is not limited by the user's definition, and the output is a control signal.One of the advantages of using data electronic loggers is their internal monitoring signals. Most can directly measure several different input signals without the need for additional signal monitoring devices. One channel can monitor thermocouples, RTDs, and voltages.Thermocouples provide valuable compensation for accurate temperature measurements. They are typically equipped with multi-channel cards. Built-in intelligent electronic data recorder helps you set the measurement period and specify the parameters for each channel. Once you set it all up, the data electronic recorder will behave like an unbeatable device. The data they store is distributed in memory and can hold 500,000 or more readings.Connecting to a PC makes it easy to transfer data to a computer for further analysis. Most data electronic recorders can be designed to be flexible and simple to configure and operate, and most provide remote location operation options via battery packs or other methods. Thanks to the A/D conversion technology, certain data electronic recorders have a lower reading rate, especially when compared with PC plug-in cards. However, a reading rate of 250 per second is relatively rare. Keep in mind that many of the phenomena that are being measured are physical in nature, such as temperature, pressure, and flow, and there are generallyfewer changes. In addition, because of the monitoring accuracy of the data electron loggers, a large amount of average reading is not necessary, just as they are often stuck on PC plug-in cards.Front-end data acquisition is often done as a module and is typically connected to a PC or controller. They are used in automated tests to collect data, control and cycle detection signals for other test equipment. Send signal test equipment spare parts. The efficiency of the front-end operation is very high, and can match the speed and accuracy with the best stand-alone instrument. Front-end data acquisition works in many models, including VXI versions such as the Agilent E1419A multi-function measurement and VXI control model, as well as a proprietary card elevator. Although the cost of front-end units has been reduced, these systems can be very expensive unless you need to provide high levels of operation, and finding their prices is prohibited. On the other hand, they do provide considerable flexibility and measurement capabilities.Good, low-cost electronic data loggers have the right number of channels (20-60 channels) and scan rates are relatively low but are common enough for most engineers. Some of the key applications include:•product features•Hot die cutting of electronic products•Test of the environmentEnvironmental monitoring•Composition characteristics•Battery testBuilding and computer capacity monitoringA new system designThe conceptual model of a universal system can be applied to the analysis phase of a specific system to better understand the problem and to specify the best solution more easily based on the specific requirements of a particular system. The conceptual model of a universal system can also be used as a starting point for designing a specific system. Therefore, using a general-purpose conceptual model will save time and reduce the cost of specific system development. To test this hypothesis, we developed DAS for railway equipment based on our generic DAS concept model. In this section, we summarize the main results and conclusions of this DAS development.We analyzed the device model package. The result of this analysis is a partial conceptual model of a system consisting of a three-tier device model. We analyzed the equipment project package in the equipment environment. Based on this analysis, we have listed a three-level item hierarchy in the conceptual model of the system. Equipment projects are specialized for individual equipment projects.We analyzed the equipment model monitoring standard package in the equipment context. One of the requirements of this system is the ability to use a predefined set of data to record specific status monitoring reports. We analyzed the equipment project monitoring standard package in the equipment environment. The requirements of the system are: (i) the ability to record condition monitoring reports and event monitoring reports corresponding to the items, which can be triggered by time triggering conditions or event triggering conditions; (ii) the definition of private and public monitoring standards; (iii) Ability to define custom and predefined train data sets. Therefore, we have introduced the "monitoring standards for equipment projects", "public standards", "special standards", "equipment monitoring standards", "equipment condition monitoring standards", "equipment project status monitoring standards and equipment project event monitoring standards, respectively Training item triggering conditions, training item time triggering conditions and training item event triggering conditions are device equipment trigger conditions, equipment item time trigger conditions and device project event trigger condition specialization; and training item data sets, training custom data Sets and trains predefined data sets, which are device project data sets, custom data sets, and specialized sets of predefined data sets.Finally, we analyzed the observations and monitoring reports in the equipment environment. The system's requirement is to recordmeasurements and category observations. In addition, status and incident monitoring reports can be recorded. Therefore, we introduce the concept of observation, measurement, classification observation and monitoring report into the conceptual model of the system.Our generic DAS concept model plays an important role in the design of DAS equipment. We use this model to better organize the data that will be used by system components. Conceptual models also make it easier to design certain components in the system. Therefore, we have an implementation in which a large number of design classes represent the concepts specified in our generic DAS conceptual model. Through an industrial example, the development of this particular DAS demonstrates the usefulness of a generic system conceptual model for developing a particular system.中文译文数据采集系统Txomin Nieva数据采集系统, 正如名字所暗示的, 是一种用来采集信息成文件或分析一些现象的产品或过程。
工程造价专业毕业外文文献、中英对照
工程造价专业毕业外文文献、中英对照中文翻译:工程造价专业毕业外文文献工程造价专业是一种重要的工程技术专业,主要负责工程投资的评估、选择和控制工程项目成本,以及项目质量、进度和安全。
因此,工程造价专业需要具备丰富的知识和技能,包括工程建设、经济学、管理学、数学、统计学等方面。
为了提高工程造价专业学生的综合能力,学习外文文献是不可或缺的步骤。
本文将介绍几篇与工程造价专业相关的外文文献,并提供中英文对照。
1)《The Role of Quantity Surveyors in Sustainable Construction》该文研究了数量调查师在可持续建筑中的作用,并深入探讨了数量调查师在项目的可持续性评估、营建阶段和运营阶段的角色和责任。
该文指出,数量调查师可以通过成本控制、资源利用、和材料选择等方面促进可持续建筑的发展,为未来可持续发展提供支持。
中文翻译:数量调查师在可持续建筑中的作用2)《Cost engineering》该文研究了造价工程的理论和实践,并提供了一系列工具和方法用于项目成本的控制和评估。
该文还深入探讨了工程造价和项目管理之间的关系,并提供了一些实用的案例研究来说明造价工程的实际应用。
中文翻译:造价工程3)《Construction cost management: learning from case studies》该文通过案例分析的方式来探讨建筑项目成本管理的实践。
该文提供了多个案例研究,旨在向读者展示如何运用不同的方法来控制和评估项目成本,并阐述了思考成本问题时需要考虑的多个因素。
中文翻译:建筑项目成本管理:案例学习4)《Project Cost Estimation and Control: A Practical Guide to Construction Management》该书是一本实用指南,详细介绍了在工程起始阶段进行项目成本估算的方法和技巧,以及如何在项目执行阶段进行成本控制。
英文文献小短文(原文加汉语翻译)
A fern that hyperaccumulates arsenic(这是题目,百度一下就能找到原文好,原文还有表格,我没有翻译)A hardy, versatile, fast-growing plant helps to remove arsenic from contaminated soilsContamination of soils with arsenic,which is both toxic and carcinogenic, is widespread1. We have discovered that the fern Pteris vittata (brake fern) is extremely efficient in extracting arsenic from soils and translocating it into its above-ground biomass. This plant —which, to our knowledge, is the first known arsenic hyperaccumulator as well as the first fern found to function as a hyperaccumulator— has many attributes that recommend it for use in the remediation of arsenic-contaminated soils.We found brake fern growing on a site in Central Florida contaminated with chromated copper arsenate (Fig. 1a). We analysed the fronds of plants growing at the site for total arsenic by graphite furnace atomic absorption spectroscopy. Of 14 plant species studied, only brake fern contained large amounts of arsenic (As;3,280–4,980 We collected additional samples of the plant and soil from the contaminated site –1,603 As) and from an uncontaminated site –As). Brake fern extracted arsenic efficiently from these soils into its fronds: plantsgrowing in the contaminated site contained 1,442–7,526 Arsenic and those from the uncontaminated site contained –These values are much higher than those typical for plants growing in normal soil, which contain less than of arsenic3.As well as being tolerant of soils containing as much as 1,500 arsenic, brake fern can take up large amounts of arsenic into its fronds in a short time (Table 1). Arsenic concentration in fern fronds growing in soil spiked with 1,500 Arsenic increased from to 15,861 in two weeks. Furthermore, in the same period, ferns growing in soil containing just 6 arsenic accumulated 755 Of arsenic in their fronds, a 126-fold enrichment. Arsenic concentrations in brake fernroots were less than 303 whereas those in the fronds reached 7,234 of 100 Arsenic significantly stimulated fern growth, resulting in a 40% increase in biomass compared with the control (data not shown).After 20 weeks of growth, the plant was extracted using a solution of 1:1 methanol:water to speciate arsenic with high-performance liquid chromatography–inductively coupled plasma mass spectrometry. Almost all arsenic was present as relatively toxic inorganic forms, with little detectable organoarsenic species4. The concentration of As(III) was greater in the fronds (47–80%) than in the roots %), indicating that As(V)was converted to As(III) during translocation from roots to fronds.As well as removing arsenic from soils containing different concentrations of arsenic (Table 1), brake fern also removed arsenic from soils containing different arsenic species (Fig. 1c). Again, up to 93% of the arsenic was concentrated in the fronds. Although both FeAsO4 and AlAsO4 are relatively insoluble in soils1, brake fern hyperaccumulated arsenic derived from these compounds into its fronds (136–315 levels 3–6 times greater than soil arsenic.Brake fern is mesophytic and is widely cultivated and naturalized in many areas with a mild climate. In the United States, it grows in the southeast and in southern California5. The fern is versatile and hardy, and prefers sunny (unusual for a fern) and alkaline environments (where arsenic is more available). It has considerable biomass, and is fast growing, easy to propagate,and perennial.We believe this is the first report of significant arsenic hyperaccumulation by an unmanipulated plant. Brake fern has great potential to remediate arsenic-contaminated soils cheaply and could also aid studies of arsenic uptake, translocation, speciation, distribution anddetoxification in plants.*Soil and Water Science Department, University ofFlorida, Gainesville, Florida 32611-0290, USAe-mail†Cooperative Extension Service, University ofGeorgia, Terrell County, PO Box 271, Dawson,Georgia 31742, USA‡Department of Chemistry & SoutheastEnvironmental Research Center, FloridaInternational University, Miami, Florida 33199,1. Nriagu, J. O. (ed.) Arsenic in the Environment Part 1: Cycling and Characterization (Wiley, New York, 1994).2. Brooks, R. R. (ed.) Plants that Hyperaccumulate Heavy Metals (Cambridge Univ. Press, 1998).3. Kabata-Pendias, A. & Pendias, H. in Trace Elements in Soils and Plants 203–209 (CRC, Boca Raton, 1991).4. Koch, I., Wang, L., Ollson, C. A., Cullen, W. R. & Reimer, K. J. Envir. Sci. Technol. 34, 22–26 (2000).5. Jones, D. L. Encyclopaedia of Ferns (Lothian, Melbourne, 1987).积累砷的蕨类植物耐寒,多功能,生长快速的植物,有助于从污染土壤去除砷有毒和致癌的土壤砷污染是非常广泛的。
英文文献及翻译(计算机专业)
英文文献及翻译(计算机专业)The increasing complexity of design resources in a net-based collaborative XXX common systems。
design resources can be organized in n with design activities。
A task is formed by a set of activities and resources linked by logical ns。
XXX managementof all design resources and activities via a Task Management System (TMS)。
which is designed to break down tasks and assign resources to task nodes。
This XXX。
2 Task Management System (TMS)TMS is a system designed to manage the tasks and resources involved in a design project。
It poses tasks into smaller subtasks。
XXX management of all design resources and activities。
TMS assigns resources to task nodes。
XXX。
3 Collaborative DesignCollaborative design is a process that XXX a common goal。
In a net-based collaborative design environment。
n XXX n for all design resources and activities。
英文文献小短文(原文加汉语翻译)
A fern that hyperaccumulates arsenic(这是题目,百度一下就能找到原文好,原文还有表格,我没有翻译)A hardy, versatile, fast-growing plant helps to remove arsenic from contaminated soilsContamination of soils with arsenic,which is both toxic and carcinogenic, is widespread1. We have discovered that the fern Pteris vittata (brake fern) is extremely efficient in extracting arsenic from soils and translocating it into its above-ground biomass. This plant —which, to our knowledge, is the first known arsenic hyperaccumulator as well as the first fern found to function as a hyperaccumulator— has many attributes that recommend it for use in the remediation of arsenic-contaminated soils.We found brake fern growing on a site in Central Florida contaminated with chromated copper arsenate (Fig. 1a). We analysed the fronds of plants growing at the site for total arsenic by graphite furnace atomic absorption spectroscopy. Of 14 plant species studied, only brake fern contained large amounts of arsenic (As;3,280–4,980 p.p.m.). We collected additional samples of the plant and soil from the contaminated site (18.8–1,603 p.p.m. As) and from an uncontaminated site (0.47–7.56 p.p.m. As). Brake fern extracted arsenic efficiently from these soils into its fronds: plants growing in the contaminated site contained 1,442–7,526p.p.m. Arsenic and those from the uncontaminated site contained 11.8–64.0 p.p.m. These values are much higher than those typical for plants growing in normal soil, which contain less than 3.6 p.p.m. of arsenic3.As well as being tolerant of soils containing as much as 1,500 p.p.m. arsenic, brake fern can take up large amounts of arsenic into its fronds in a short time (Table 1). Arsenic concentration in fern fronds growing in soil spiked with 1,500 p.p.m. Arsenic increased from 29.4 to 15,861 p.p.m. in two weeks. Furthermore, in the same period, ferns growing in soil containing just 6 p.p.m. arsenic accumulated 755 p.p.m. Of arsenic in their fronds, a 126-fold enrichment. Arsenic concentrations in brake fern roots were less than 303 p.p.m., whereas those in the fronds reached 7,234 p.p.m.Addition of 100 p.p.m. Arsenic significantly stimulated fern growth, resulting in a 40% increase in biomass compared with the control (data not shown).After 20 weeks of growth, the plant was extracted using a solution of 1:1 methanol:water to speciate arsenic with high-performance liquid chromatography–inductively coupled plasma mass spectrometry. Almostall arsenic was present as relatively toxic inorganic forms, with little detectable organoarsenic species4. The concentration of As(III) was greater in the fronds (47–80%) than in the roots (8.3%), indicating that As(V) was converted to As(III) during translocation from roots to fronds.As well as removing arsenic from soils containing different concentrations of arsenic (Table 1), brake fern also removed arsenic from soils containing different arsenic species (Fig. 1c). Again, up to 93% of the arsenic was concentrated in the fronds. Although both FeAsO4 and AlAsO4 are relatively insoluble in soils1, brake fern hyperaccumulated arsenic derived from these compounds into its fronds (136–315 p.p.m.)at levels 3–6 times greater than soil arsenic.Brake fern is mesophytic and is widely cultivated and naturalized in many areas with a mild climate. In the United States, it grows in the southeast and in southern California5. The fern is versatile and hardy, and prefers sunny (unusual for a fern) and alkaline environments (where arsenic is more available). It has considerable biomass, and is fast growing, easy to propagate,and perennial.We believe this is the first report of significant arsenic hyperaccumulationby an unmanipulated plant. Brake fern has great potential to remediate arsenic-contaminated soils cheaply and could also aid studies of arsenic uptake, translocation, speciation, distribution and detoxification in plants. *Soil and Water Science Department, University ofFlorida, Gainesville, Florida 32611-0290, USAe-mail: lqma@†Cooperative Extension Service, University ofGeorgia, Terrell County, PO Box 271, Dawson,Georgia 31742, USA‡Department of Chemistry & SoutheastEnvironmental Research Center, FloridaInternational University, Miami, Florida 33199,1. Nriagu, J. O. (ed.) Arsenic in the Environment Part 1: Cyclingand Characterization (Wiley, New York, 1994).2. Brooks, R. R. (ed.) Plants that Hyperaccumulate Heavy Metals (Cambridge Univ. Press, 1998).3. Kabata-Pendias, A. & Pendias, H. in Trace Elements in Soils and Plants 203–209 (CRC, Boca Raton, 1991).4. Koch, I., Wang, L., Ollson, C. A., Cullen, W. R. & Reimer, K. J. Envir. Sci. Technol. 34, 22–26 (2000).5. Jones, D. L. Encyclopaedia of Ferns (Lothian, Melbourne, 1987).积累砷的蕨类植物耐寒,多功能,生长快速的植物,有助于从污染土壤去除砷有毒和致癌的土壤砷污染是非常广泛的。
机床——机械类外文文献翻译、中英文翻译
毕业设计(论文)外文资料翻译系部:专业:姓名:学号:外文出处:English For Electromechanical(用外文写)Engineering附件:1.外文资料翻译译文;2.外文原文。
附件1:外文资料翻译译文机床机床是用于切削金属的机器。
工业上使用的机床要数车床、钻床和铣床最为重要。
其它类型的金属切削机床在金属切削加工方面不及这三种机床应用广泛。
车床通常被称为所有类型机床的始祖。
为了进行车削,当工件旋转经过刀具时,车床用一把单刃刀具切除金属。
用车削可以加工各种圆柱型的工件,如:轴、齿轮坯、皮带轮和丝杠轴。
镗削加工可以用来扩大和精加工定位精度很高的孔。
钻削是由旋转的钻头完成的。
大多数金属的钻削由麻花钻来完成。
用来进行钻削加工的机床称为钻床。
铰孔和攻螺纹也归类为钻削过程。
铰孔是从已经钻好的孔上再切除少量的金属。
攻螺纹是在内孔上加工出螺纹,以使螺钉或螺栓旋进孔内。
铣削由旋转的、多切削刃的铣刀来完成。
铣刀有多种类型和尺寸。
有些铣刀只有两个切削刃,而有些则有多达三十或更多的切削刃。
铣刀根据使用的刀具不同能加工平面、斜面、沟槽、齿轮轮齿和其它外形轮廓。
牛头刨床和龙门刨床用单刃刀具来加工平面。
用牛头刨床进行加工时,刀具在机床上往复运动,而工件朝向刀具自动进给。
在用龙门刨床进行加工时,工件安装在工作台上,工作台往复经过刀具而切除金属。
工作台每完成一个行程刀具自动向工件进给一个小的进给量。
磨削利用磨粒来完成切削工作。
根据加工要求,磨削可分为精密磨削和非精密磨削。
精密磨削用于公差小和非常光洁的表面,非精密磨削用于在精度要求不高的地方切除多余的金属。
车床车床是用来从圆形工件表面切除金属的机床,工件安装在车床的两个顶尖之间,并绕顶尖轴线旋转。
车削工件时,车刀沿着工件的旋转轴线平行移动或与工件的旋转轴线成一斜角移动,将工件表面的金属切除。
车刀的这种位移称为进给。
车刀装夹在刀架上,刀架则固定在溜板上。
溜板是使刀具沿所需方向进行进给的机构。
外文文献及翻译
((英文参考文献及译文)二〇一六年六月本科毕业论文 题 目:STATISTICAL SAMPLING METHOD, USED INTHE AUDIT学生姓名:王雪琴学 院:管理学院系 别:会计系专 业:财务管理班 级:财管12-2班 学校代码: 10128 学 号: 201210707016Statistics and AuditRomanian Statistical Review nr. 5 / 2010STATISTICAL SAMPLING METHOD, USED IN THE AUDIT - views, recommendations, fi ndingsPhD Candidate Gabriela-Felicia UNGUREANUAbstractThe rapid increase in the size of U.S. companies from the earlytwentieth century created the need for audit procedures based on the selectionof a part of the total population audited to obtain reliable audit evidence, tocharacterize the entire population consists of account balances or classes oftransactions. Sampling is not used only in audit – is used in sampling surveys,market analysis and medical research in which someone wants to reach aconclusion about a large number of data by examining only a part of thesedata. The difference is the “population” from which the sample is selected, iethat set of data which is intended to draw a conclusion. Audit sampling appliesonly to certain types of audit procedures.Key words: sampling, sample risk, population, sampling unit, tests ofcontrols, substantive procedures.Statistical samplingCommittee statistical sampling of American Institute of CertifiedPublic Accountants of (AICPA) issued in 1962 a special report, titled“Statistical sampling and independent auditors’ which allowed the use ofstatistical sampling method, in accordance with Generally Accepted AuditingStandards (GAAS). During 1962-1974, the AICPA published a series of paperson statistical sampling, “Auditor’s Approach to Statistical Sampling”, foruse in continuing professional education of accountants. During 1962-1974,the AICPA published a series of papers on statistical sampling, “Auditor’sApproach to Statistical Sampling”, for use in continuing professional educationof accountants. In 1981, AICPA issued the professional standard, “AuditSampling”, which provides general guidelines for both sampling methods,statistical and non-statistical.Earlier audits included checks of all transactions in the period coveredby the audited financial statements. At that time, the literature has not givenparticular attention to this subject. Only in 1971, an audit procedures programprinted in the “Federal Reserve Bulletin (Federal Bulletin Stocks)” includedseveral references to sampling such as selecting the “few items” of inventory.Statistics and Audit The program was developed by a special committee, which later became the AICPA, that of Certified Public Accountants American Institute.In the first decades of last century, the auditors often applied sampling, but sample size was not in related to the efficiency of internal control of the entity. In 1955, American Institute of Accountants has published a study case of extending the audit sampling, summarizing audit program developed by certified public accountants, to show why sampling is necessary to extend the audit. The study was important because is one of the leading journal on sampling which recognize a relationship of dependency between detail and reliability testing of internal control.In 1964, the AICPA’s Auditing Standards Board has issued a report entitled “The relationship between statistical sampling and Generally Accepted Auditing Standards (GAAS)” which illustrated the relationship between the accuracy and reliability in sampling and provisions of GAAS.In 1978, the AICPA published the work of Donald M. Roberts,“Statistical Auditing”which explains the underlying theory of statistical sampling in auditing.In 1981, AICPA issued the professional standard, named “Audit Sampling”, which provides guidelines for both sampling methods, statistical and non-statistical.An auditor does not rely solely on the results of a single procedure to reach a conclusion on an account balance, class of transactions or operational effectiveness of the controls. Rather, the audit findings are based on combined evidence from several sources, as a consequence of a number of different audit procedures. When an auditor selects a sample of a population, his objective is to obtain a representative sample, ie sample whose characteristics are identical with the population’s characteristics. This means that selected items are identical with those remaining outside the sample.In practice, auditors do not know for sure if a sample is representative, even after completion the test, but they “may increase the probability that a sample is representative by accuracy of activities made related to design, sample selection and evaluation” [1]. Lack of specificity of the sample results may be given by observation errors and sampling errors. Risks to produce these errors can be controlled.Observation error (risk of observation) appears when the audit test did not identify existing deviations in the sample or using an inadequate audit technique or by negligence of the auditor.Sampling error (sampling risk) is an inherent characteristic of the survey, which results from the fact that they tested only a fraction of the total population. Sampling error occurs due to the fact that it is possible for Revista Română de Statistică nr. 5 / 2010Statistics and Auditthe auditor to reach a conclusion, based on a sample that is different from the conclusion which would be reached if the entire population would have been subject to audit procedures identical. Sampling risk can be reduced by adjusting the sample size, depending on the size and population characteristics and using an appropriate method of selection. Increasing sample size will reduce the risk of sampling; a sample of the all population will present a null risk of sampling.Audit Sampling is a method of testing for gather sufficient and appropriate audit evidence, for the purposes of audit. The auditor may decide to apply audit sampling on an account balance or class of transactions. Sampling audit includes audit procedures to less than 100% of the items within an account balance or class of transactions, so all the sample able to be selected. Auditor is required to determine appropriate ways of selecting items for testing. Audit sampling can be used as a statistical approach and a non- statistical.Statistical sampling is a method by which the sample is made so that each unit consists of the total population has an equal probability of being included in the sample, method of sample selection is random, allowed to assess the results based on probability theory and risk quantification of sampling. Choosing the appropriate population make that auditor’ findings can be extended to the entire population.Non-statistical sampling is a method of sampling, when the auditor uses professional judgment to select elements of a sample. Since the purpose of sampling is to draw conclusions about the entire population, the auditor should select a representative sample by choosing sample units which have characteristics typical of that population. Results will not extrapolate the entire population as the sample selected is representative.Audit tests can be applied on the all elements of the population, where is a small population or on an unrepresentative sample, where the auditor knows the particularities of the population to be tested and is able to identify a small number of items of interest to audit. If the sample has not similar characteristics for the elements of the entire population, the errors found in the tested sample can not extrapolate.Decision of statistical or non-statistical approach depends on the auditor’s professional judgment which seeking sufficient appropriate audits evidence on which to completion its findings about the audit opinion.As a statistical sampling method refer to the random selection that any possible combination of elements of the community is equally likely to enter the sample. Simple random sampling is used when stratification was not to audit. Using random selection involves using random numbers generated byRomanian Statistical Review nr. 5 / 2010Statistics and Audit a computer. After selecting a random starting point, the auditor found the first random number that falls within the test document numbers. Only when the approach has the characteristics of statistical sampling, statistical assessments of risk are valid sampling.In another variant of the sampling probability, namely the systematic selection (also called random mechanical) elements naturally succeed in office space or time; the auditor has a preliminary listing of the population and made the decision on sample size. “The auditor calculated a counting step, and selects the sample element method based on step size. Step counting is determined by dividing the volume of the community to sample the number of units desired. Advantages of systematic screening are its usability. In most cases, a systematic sample can be extracted quickly and method automatically arranges numbers in successive series.”[2].Selection by probability proportional to size - is a method which emphasizes those population units’recorded higher values. The sample is constituted so that the probability of selecting any given element of the population is equal to the recorded value of the item;Stratifi ed selection - is a method of emphasis of units with higher values and is registered in the stratification of the population in subpopulations. Stratification provides a complete picture of the auditor, when population (data table to be analyzed) is not homogeneous. In this case, the auditor stratifies a population by dividing them into distinct subpopulations, which have common characteristics, pre-defined. “The objective of stratification is to reduce the variability of elements in each layer and therefore allow a reduction in sample size without a proportionate increase in the risk of sampling.” [3] If population stratification is done properly, the amount of sample size to come layers will be less than the sample size that would be obtained at the same level of risk given sample with a sample extracted from the entire population. Audit results applied to a layer can be designed only on items that are part of that layer.I appreciated as useful some views on non-statistical sampling methods, which implies that guided the selection of the sample selecting each element according to certain criteria determined by the auditor. The method is subjective; because the auditor selects intentionally items containing set features him.The selection of the series is done by selecting multiple elements series (successive). Using sampling the series is recommended only if a reasonable number of sets used. Using just a few series there is a risk that the sample is not representative. This type of sampling can be used in addition to other samples, where there is a high probability of occurrence of errors. At the arbitrary selection, no items are selected preferably from the auditor, Revista Română de Statistică nr. 5 / 2010Statistics and Auditthat regardless of size or source or characteristics. Is not the recommended method, because is not objective.That sampling is based on the auditor’s professional judgment, which may decide which items can be part or not sampled. Because is not a statistical method, it can not calculate the standard error. Although the sample structure can be constructed to reproduce the population, there is no guarantee that the sample is representative. If omitted a feature that would be relevant in a particular situation, the sample is not representative.Sampling applies when the auditor plans to make conclusions about population, based on a selection. The auditor considers the audit program and determines audit procedures which may apply random research. Sampling is used by auditors an internal control systems testing, and substantive testing of operations. The general objectives of tests of control system and operations substantive tests are to verify the application of pre-defined control procedures, and to determine whether operations contain material errors.Control tests are intended to provide evidence of operational efficiency and controls design or operation of a control system to prevent or detect material misstatements in financial statements. Control tests are necessary if the auditor plans to assess control risk for assertions of management.Controls are generally expected to be similarly applied to all transactions covered by the records, regardless of transaction value. Therefore, if the auditor uses sampling, it is not advisable to select only high value transactions. Samples must be chosen so as to be representative population sample.An auditor must be aware that an entity may change a special control during the course of the audit. If the control is replaced by another, which is designed to achieve the same specific objective, the auditor must decide whether to design a sample of all transactions made during or just a sample of transactions controlled again. Appropriate decision depends on the overall objective of the audit test.Verification of internal control system of an entity is intended to provide guidance on the identification of relevant controls and design evaluation tests of controls.Other tests:In testing internal control system and testing operations, audit sample is used to estimate the proportion of elements of a population containing a characteristic or attribute analysis. This proportion is called the frequency of occurrence or percentage of deviation and is equal to the ratio of elements containing attribute specific and total number of population elements. WeightRomanian Statistical Review nr. 5 / 2010Statistics and Audit deviations in a sample are determined to calculate an estimate of the proportion of the total population deviations.Risk associated with sampling - refers to a sample selection which can not be representative of the population tested. In other words, the sample itself may contain material errors or deviations from the line. However, issuing a conclusion based on a sample may be different from the conclusion which would be reached if the entire population would be subject to audit.Types of risk associated with sampling:Controls are more effective than they actually are or that there are not significant errors when they exist - which means an inappropriate audit opinion. Controls are less effective than they actually are that there are significant errors when in fact they are not - this calls for additional activities to establish that initial conclusions were incorrect.Attributes testing - the auditor should be defining the characteristics to test and conditions for misconduct. Attributes testing will make when required objective statistical projections on various characteristics of the population. The auditor may decide to select items from a population based on its knowledge about the entity and its environment control based on risk analysis and the specific characteristics of the population to be tested.Population is the mass of data on which the auditor wishes to generalize the findings obtained on a sample. Population will be defined compliance audit objectives and will be complete and consistent, because results of the sample can be designed only for the population from which the sample was selected.Sampling unit - a unit of sampling may be, for example, an invoice, an entry or a line item. Each sample unit is an element of the population. The auditor will define the sampling unit based on its compliance with the objectives of audit tests.Sample size - to determine the sample size should be considered whether sampling risk is reduced to an acceptable minimum level. Sample size is affected by the risk associated with sampling that the auditor is willing to accept it. The risk that the auditor is willing to accept lower, the sample will be higher.Error - for detailed testing, the auditor should project monetary errors found in the sample population and should take into account the projected error on the specific objective of the audit and other audit areas. The auditor projects the total error on the population to get a broad perspective on the size of the error and comparing it with tolerable error.For detailed testing, tolerable error is tolerable and misrepresentations Revista Română de Statistică nr. 5 / 2010Statistics and Auditwill be a value less than or equal to materiality used by the auditor for the individual classes of transactions or balances audited. If a class of transactions or account balances has been divided into layers error is designed separately for each layer. Design errors and inconsistent errors for each stratum are then combined when considering the possible effect on the total classes of transactions and account balances.Evaluation of sample results - the auditor should evaluate the sample results to determine whether assessing relevant characteristics of the population is confirmed or needs to be revised.When testing controls, an unexpectedly high rate of sample error may lead to an increase in the risk assessment of significant misrepresentation unless it obtained additional audit evidence to support the initial assessment. For control tests, an error is a deviation from the performance of control procedures prescribed. The auditor should obtain evidence about the nature and extent of any significant changes in internal control system, including the staff establishment.If significant changes occur, the auditor should review the understanding of internal control environment and consider testing the controls changed. Alternatively, the auditor may consider performing substantive analytical procedures or tests of details covering the audit period.In some cases, the auditor might not need to wait until the end audit to form a conclusion about the effectiveness of operational control, to support the control risk assessment. In this case, the auditor might decide to modify the planned substantive tests accordingly.If testing details, an unexpectedly large amount of error in a sample may cause the auditor to believe that a class of transactions or account balances is given significantly wrong in the absence of additional audit evidence to show that there are not material misrepresentations.When the best estimate of error is very close to the tolerable error, the auditor recognizes the risk that another sample have different best estimate that could exceed the tolerable error.ConclusionsFollowing analysis of sampling methods conclude that all methods have advantages and disadvantages. But the auditor is important in choosing the sampling method is based on professional judgment and take into account the cost / benefit ratio. Thus, if a sampling method proves to be costly auditor should seek the most efficient method in view of the main and specific objectives of the audit.Romanian Statistical Review nr. 5 / 2010Statistics and Audit The auditor should evaluate the sample results to determine whether the preliminary assessment of relevant characteristics of the population must be confirmed or revised. If the evaluation sample results indicate that the relevant characteristics of the population needs assessment review, the auditor may: require management to investigate identified errors and likelihood of future errors and make necessary adjustments to change the nature, timing and extent of further procedures to take into account the effect on the audit report.Selective bibliography:[1] Law no. 672/2002 updated, on public internal audit[2] Arens, A şi Loebbecke J - Controve …Audit– An integrate approach”, 8th edition, Arc Publishing House[3] ISA 530 - Financial Audit 2008 - International Standards on Auditing, IRECSON Publishing House, 2009- Dictionary of macroeconomics, Ed C.H. Beck, Bucharest, 2008Revista Română de Statistică nr. 5 / 2010Statistics and Audit摘要美国公司的规模迅速增加,从第二十世纪初创造了必要的审计程序,根据选定的部分总人口的审计,以获得可靠的审计证据,以描述整个人口组成的帐户余额或类别的交易。
关于会计的英文文献原文(带中文翻译)
The Optimization Method of Financial Statements Based on Accounting Management TheoryABSTRACTThis paper develops an approach to enhance the reliability and usefulness of financial statements. International Financial Reporting Standards (IFRS) was fundamentally flawed by fair value accounting and asset-impairment accounting. According to legal theory and accounting theory, accounting data must have legal evidence as its source document. The conventional “mixed attribute” accounting system should be re placed by a “segregated” system with historical cost and fair value being kept strictly apart in financial statements. The proposed optimizing method will significantly enhance the reliability and usefulness of financial statements.I.. INTRODUCTIONBased on international-accounting-convergence approach, the Ministry of Finance issued the Enterprise Accounting Standards in 2006 taking the International Financial Reporting Standards (hereinafter referred to as “the International Standards”) for reference. The Enterprise Accounting Standards carries out fair value accounting successfully, and spreads the sense that accounting should reflect market value objectively. The objective of accounting reformation following-up is to establish the accounting theory and methodology which not only use international advanced theory for reference, but also accord with the needs of China's socialist market economy construction. On the basis of a thorough evaluation of the achievements and limitations of International Standards, this paper puts forward a stand that to deepen accounting reformation and enhance the stability of accounting regulations.II. OPTIMIZA TION OF FINANCIAL STATEMENTS SYSTEM: PARALLELING LISTING OF LEGAL FACTS AND FINANCIAL EXPECTA TIONAs an important management activity, accounting should make use of information systems based on classified statistics, and serve for both micro-economic management and macro-economic regulation at the same time. Optimization of financial statements system should try to take all aspects of the demands of the financial statements in both macro and micro level into account.Why do companies need to prepare financial statements? Whose demands should be considered while preparing financial statements? Those questions are basic issues we should consider on the optimization of financial statements. From the perspective of "public interests", reliability and legal evidence are required as qualitative characters, which is the origin of the traditional "historical cost accounting". From the perspective of "private interest", security investors and financial regulatory authoritieshope that financial statements reflect changes of market prices timely recording "objective" market conditions. This is the origin of "fair value accounting". Whether one set of financial statements can be compatible with these two different views and balance the public interest and private interest? To solve this problem, we design a new balance sheet and an income statement.From 1992 to 2006, a lot of new ideas and new perspectives are introduced into China's accounting practices from international accounting standards in a gradual manner during the accounting reform in China. These ideas and perspectives enriched the understanding of the financial statements in China. These achievements deserve our full assessment and should be fully affirmed. However, academia and standard-setters are also aware that International Standards are still in the process of developing .The purpose of proposing new formats of financial statements in this paper is to push forward the accounting reform into a deeper level on the basis of international convergence.III. THE PRACTICABILITY OF IMPROVING THE FINANCIAL STATEMENTS SYSTEMWhether the financial statements are able to maintain their stability? It is necessary to mobilize the initiatives of both supply-side and demand-side at the same time. We should consider whether financial statements could meet the demands of the macro-economic regulation and business administration, and whether they are popular with millions of accountants.Accountants are responsible for preparing financial statements and auditors are responsible for auditing. They will benefit from the implementation of the new financial statements.Firstly, for the accountants, under the isolated design of historical cost accounting and fair value accounting, their daily accounting practice is greatly simplified. Accounting process will not need assets impairment and fair value any longer. Accounting books will not record impairment and appreciation of assets any longer, for the historical cost accounting is comprehensively implemented. Fair value information will be recorded in accordance with assessment only at the balance sheet date and only in the annual financial statements. Historical cost accounting is more likely to be recognized by the tax authorities, which saves heavy workload of the tax adjustment. Accountants will not need to calculate the deferred income tax expense any longer, and the profit-after-tax in the solid line table is acknowledged by the Company Law, which solves the problem of determining the profit available for distribution.Accountants do not need to record the fair value information needed by security investors in the accounting books; instead, they only need to list the fair value information at the balance sheet date. In addition, because the data in the solid line table has legal credibility, so the legal risks of accountants can be well controlled. Secondly, the arbitrariness of the accounting process will be reduced, and the auditors’ review process will be greatly simplified. The independent auditors will not have to bear the considerable legal risk for the dotted-line table they audit, because the risk of fair value information has been prompted as "not supported by legalevidences". Accountants and auditors can quickly adapt to this financial statements system, without the need of training. In this way, they can save a lot of time to help companies to improve management efficiency. Surveys show that the above design of financial statements is popular with accountants and auditors. Since the workloads of accounting and auditing have been substantially reduced, therefore, the total expenses for auditing and evaluation will not exceed current level as well.In short, from the perspectives of both supply-side and demand-side, the improved financial statements are expected to enhance the usefulness of financial statements, without increase the burden of the supply-side.IV. CONCLUSIONS AND POLICY RECOMMENDATIONSThe current rule of mixed presentation of fair value data and historical cost data could be improved. The core concept of fair value is to make financial statements reflect the fair value of assets and liabilities, so that we can subtract the fair value of liabilities from assets to obtain the net fair value.However, the current International Standards do not implement this concept, but try to partly transform the historical cost accounting, which leads to mixed using of impairment accounting and fair value accounting. China's accounting academic research has followed up step by step since 1980s, and now has already introduced a mixed-attributes model into corporate financial statements.By distinguishing legal facts from financial expectations, we can balance public interests and private interests and can redesign the financial statements system with enhancing management efficiency and implementing higher-level laws as main objective. By presenting fair value and historical cost in one set of financial statements at the same time, the statements will not only meet the needs of keeping books according to domestic laws, but also meet the demand from financial regulatory authorities and security investorsWe hope that practitioners and theorists offer advices and suggestions on the problem of improving the financial statements to build a financial statements system which not only meets the domestic needs, but also converges with the International Standards.基于会计管理理论的财务报表的优化方法摘要本文提供了一个方法,以提高财务报表的可靠性和实用性。
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。
冲压模具技术外文文献翻译中英文
外文文献翻译(含:英文原文及中文译文)英文原文Stamping technologyIntroductionIn the current fierce market competition, the product to market sooner or later is often the key to the success or failure. Mould is a product of high quality, high efficiency production tool, mold development cycle of the main part of the product development cycle. So the customer requirements for mold development cycle shorter, many customers put the mould delivery date in the first place, and then the quality and price. Therefore, how to ensure the quality, control the cost under the premise of processing mould is a problem worthy of serious consideration. Mold processing technology is an advanced manufacturing technology, has become an important development direction, in the aerospace, automotive, machinery and other industries widely used. Mold processing technology, can improve the comprehensive benefit and competitiveness of manufacturing industry. Research and establish mold process database, provide production enterprises urgently need to high speed cutting processing data, to the promotion of high-speed machining technology has very important significance. This article's main goal is to build a stamping die processing, mold manufacturing enterprises in theactual production combined cutting tool, workpiece and machine tool with the actual situation of enterprise itself accumulate to high speed cutting processing instance, process parameters and experience of high speed cutting database selectively to store data, not only can save a lot of manpower and material resources, financial resources, but also can guide the high speed machining production practice, to improve processing efficiency, reduce the tooling cost and obtain higher economic benefits.1. The concept, characteristics and application of stampingStamping is a pressure processing method that uses a mold installed on a press machine (mainly a press) to apply pressure to a material to cause it to separate or plastically deform, thereby obtaining a desired part (commonly referred to as a stamped or stamped part). Stamping is usually cold deformation processing of the material at room temperature, and the main use of sheet metal to form the required parts, it is also called cold stamping or sheet metal stamping. Stamping is one of the main methods of material pressure processing or plastic processing, and is affiliated with material forming engineering.The stamping die is called stamping die, or die. Dies are special tools for the batch processing of materials (metal or non-metallic) into the required stampings. Stamping is critical in stamping. There is no die that meets the requirements. Batch stamping production is difficult. Without advanced stamping, advanced stamping processes cannot be achieved.Stamping processes and dies, stamping equipment, and stamping materials constitute the three elements of stamping. Only when they are combined can stampings be obtained.Compared with other methods of mechanical processing and plastic processing, stamping processing has many unique advantages in both technical and economic aspects, and its main performance is as follows;(1) The stamping process has high production efficiency, easy operation, and easy realization of mechanization and automation. This is because stamping is accomplished by means of die and punching equipment. The number of strokes for ordinary presses can reach several tens of times per minute, and the high-speed pressure can reach hundreds or even thousands of times per minute, and each press stroke is Y ou may get a punch.(2) Since the die ensures the dimensional and shape accuracy of the stamping part during stamping, and generally does not destroy the surface quality of the stamping part, the life of the die is generally longer, so the stamping quality is stable, the interc hangeability is good, and it has “the same” Characteristics.(3) Stamping can process parts with a wide range of sizes and shapes, such as stopwatches as small as clocks, as large as automobile longitudinal beams, coverings, etc., plus the cold deformation hardening effect of materials during stamping, the strength of stamping and Thestiffness is high.(4) Stamping generally does not generate scraps, material consumption is less, and no other heating equipment is required. Therefore, it is a material-saving and energy-saving processing method, and the cost of stamping parts is low.However, the molds used for stamping are generally specialized, and sometimes a complex part requires several sets of molds for forming, and the precision of the mold manufacturing is high and the technical requirements are high. It is a technology-intensive product. Therefore, the advantages of stamping can only be fully realized in the case of large production volume of stamping parts, so as to obtain better economic benefits.Stamping is widely used in modern industrial production, especially in mass production. A considerable number of industrial sectors are increasingly using punching to process product components such as automobiles, agricultural machinery, instruments, meters, electronics, aerospace, aerospace, home appliances, and light industry. In these industrial sectors, the proportion of stamped parts is quite large, at least 60% or more, and more than 90%. Many of the parts that were manufactured in the past using forging = casting and cutting processes are now mostly replaced by light-weight, rigid stampings. Therefore, it can be said that if the stamping process cannot be adopted in production, it isdifficult for many industrial departments to increase the production efficiency and product quality, reduce the production cost, and quickly replace the product.2. Basic process and mould for stampingDue to the wide variety of stamped parts and the different shapes, sizes, and precision requirements of various parts, the stamping process used in production is also varied. Summarized, can be divided into two major categories of separation processes and forming processes; Separation process is to make the blank along a certain contour line to obtain a certain shape, size and section quality stamping (commonly referred to as blanking parts) of the process; forming process refers to The process of producing a stamped part of a certain shape and size by plastic deformation of the blank without breaking.The above two types of processes can be divided into four basic processes: blanking, bending, deep drawing and forming according to different basic deformation modes. Each basic process also includes multiple single processes.In actual production, when the production volume of the stamped part is large, the size is small and the tolerance requirement is small, it is not economical or even difficult to achieve the requirement if the stamping is performed in a single process. At this time, a centralized scheme is mostly used in the process, that is, two or more singleprocesses are concentrated in a single mold. Different methods are called combinations, and they can be divided into compound-graded and compound- Progressive three combinations.Composite stamping - A combination of two or more different single steps at the same station on the die in one press stroke.Progressive stamping - a combination of two or more different single steps on a single work station in the same mold at a single working stroke on the press.Composite - Progressive - On a die combination process consisting of composite and progressive two ways.There are many types of die structure. According to the process nature, it can be divided into blanking die, bending die, drawing die and forming die, etc.; the combination of processes can be divided into single-step die, compound die and progressive die. However, regardless of the type of die, it can be regarded as consisting of two parts: the upper die and the lower die. The upper die is fixed on the press table or the backing plate and is a fixed part of the die. During work, the blanks are positioned on the lower die surface by positioning parts, and the press sliders push the upper die downwards. The blanks are separated or plastically deformed under the action of the die working parts (ie, punch and die) to obtain the required Shape and size of punching pieces. When the upper mold is lifted, the unloading and ejecting device of the moldremoves or pushes and ejects the punching or scrap from the male and female molds for the next punching cycle.3. Current status and development direction of stamping technologyWith the continuous advancement of science and technology and the rapid development of industrial production, many new technologies, new processes, new equipment, and new materials continue to emerge, thus contributing to the constant innovation and development of stamping technology. Its main performance and development direction are as follows:(1) The theory of stamping and the stamping process The study of stamping forming theory is the basis for improving stamping technology. At present, the research on the stamping forming theory at home and abroad attaches great importance, and significant progress has been made in the study of material stamping performance, stress and strain analysis in the stamping process, study of the sheet deformation law, and the interaction between the blank and the mold. . In particular, with the rapid development of computer technology and the further improvement of plastic deformation theory, computer simulation techniques for the plastic forming process have been applied at home and abroad in recent years, namely the use of finite element (FEM) and other valuable analytical methods to simulate the plastic forming process of metals. According to the analysis results, the designer can predict the feasibility and possiblequality problems of a certain process scheme. By selecting and modifying the relevant parameters on the computer, the process and mold design can be optimized. This saves the cost of expensive trials and shortens the cycle time.Research and promotion of various pressing technologies that can increase productivity and product quality, reduce costs, and expand the range of application of stamping processes are also one of the development directions of stamping technology. At present, new precision, high-efficiency, and economical stamping processes, such as precision stamping, soft mold forming, high energy high speed forming, and dieless multi-point forming, have emerged at home and abroad. Among them, precision blanking is an effective method for improving the quality of blanking parts. It expands the scope of stamping processing. The thickness of precision blanking parts can reach 25mm at present, and the precision can reach IT16~17; use liquid, rubber, polyurethane, etc. Flexible die or die soft die forming process can process materials that are difficult to process with ordinary processing methods and parts with complex shapes, have obvious economic effects under specific production conditions, and adopt energy-efficient forming methods such as explosion for processing. This kind of sheet metal parts with complex dimensions, complex shapes, small batches, high strength and high precision has important practical significance; Superplastic forming of metal materialscan be used to replace multiple common stampings with one forming. Forming process, which has outstanding advantages for machining complex shapes and large sheet metal parts; moldless multi-point forming process is an advanced technology for forming sheet metal surfaces by replacing the traditional mold with a group of height adjustable punches. Independently designed and manufactured an international leading-edge moldless multi-point forming equipment, which solves the multi-point press forming method and can therefore be Changing the state of stress and deformation path, improving the forming limit of the material, while repeatedly using the forming technology may eliminate the residual stress within the material, the rebound-free molding. The dieless multi-point forming system takes CAD/CAM/CAE technology as the main means to quickly and economically realize the automated forming of three-dimensional surfaces.(2) Dies are the basic conditions for achieving stamping production. In the design and manufacture of stampings, they are currently developing in the following two aspects: On the one hand, in order to meet the needs of high-volume, automatic, precision, safety and other large-volume modern production, stamping is To develop high-efficiency, high-precision, high-life, multi-station, and multi-function, compared with new mold materials and heat treatment technologies, various high-efficiency, precision, CNC automatic mold processing machine toolsand testing equipment and molds CAD/CAM technology is also rapidly developing; On the other hand, in order to meet the needs of product replacement and trial production or small-batch production, zinc-based alloy die, polyurethane rubber die, sheet die, steel die, combination die and other simple die And its manufacturing technology has also been rapidly developed.Precision, high-efficiency multi-station and multi-function progressive die and large-scale complex automotive panel die represent the technical level of modern die. At present, the precision of the progressive die above 50 stations can reach 2 microns. The multifunctional progressive die can not only complete the stamping process, but also complete welding, assembly and other processes. Our country has been able to design and manufacture its own precision up to the international level of 2 to 5 microns, precision 2 to 3 microns into the distance, the total life of 100 million. China's major automotive mold enterprises have been able to produce complete sets of car cover molds, and have basically reached the international level in terms of design and manufacturing methods and means. However, the manufacturing methods and methods have basically reached the international level. The mold structure and function are also close to international Level, but there is still a certain gap compared with foreign countries in terms of manufacturing quality, accuracy, manufacturing cycle and cost.4. Stamping standardization and professional productionThe standardization and professional production of molds has been widely recognized by the mold industry. Because the die is a single-piece, small-volume production, the die parts have both certain complexity and precision, as well as a certain structural typicality. Therefore, only the standardization of the die can be achieved, so that the production of the die and the die parts can be professionalized and commercialized, thereby reducing the cost of the die, improving the quality of the die and shortening the manufacturing cycle. At present, the standard production of molds in foreign advanced industrial countries has reached 70% to 80%. Mould factories only need to design and manufacture working parts, and most of the mold parts are purchased from standard parts factories, which greatly increases productivity. The more irregular the degree of specialization of the mold manufacturing plant, the more and more detailed division of labor, such as the current mold factory, mandrel factory, heat treatment plant, and even some mold factories only specialize in the manufacture of a certain type of product or die The bending die is more conducive to the improvement of the manufacturing level and the shortening of the manufacturing cycle. China's stamp standardization and specialized production have also witnessed considerable development in recent years. In addition to the increase in the number of standard parts specialized manufacturers, the number ofstandard parts has also expanded, and the accuracy has also improved. However, the overall situation can not meet the requirements of the development of the mold industry, mainly reflected in the standardization level is not high (usually below 40%), the standard parts of the species and specifications are less, most standard parts manufacturers did not form a large-scale production, standard parts There are still many problems with quality. In addition, the sales, supply, and service of standard parts production have yet to be further improved.中文译文冲压模具技术前言在目前激烈的市场竞争中, 产品投入市场的迟早往往是成败的关键。
儿童教育外文翻译文献
儿童教育外文翻译文献(文档含中英文对照即英文原文和中文翻译)原文:The Role of Parents and Community in the Educationof the Japanese ChildHeidi KnipprathAbstractIn Japan, there has been an increased concern about family and community participation in the child’s educat ion. Traditionally, the role of parents and community in Japan has been one of support and less one of active involvement in school learning. Since the government commenced education reforms in the last quarter of the 20th century, a more active role for parents and the community in education has been encouraged. These reforms have been inspired by the need to tackle various problems that had arisen, such as the perceived harmful elements of society’spreoccupation with academic achievement and the problematic behavior of young people. In this paper, the following issues are examined: (1) education policy and reform measures with regard to parent and community involvement in the child’s education; (2) the state of parent and community involvement at the eve of the 20th century.Key Words: active involvement, community, education reform, Japan, parents, partnership, schooling, supportIntroduction: The Discourse on the Achievement GapWhen western observers are tempted to explain why Japanese students attain high achievement scores in international comparative assessment studies, they are likely to address the role of parents and in particular of the mother in the education of the child. Education mom is a phrase often brought forth in the discourse on Japanese education to depict the Japanese mother as being a pushy, and demanding home-bound tutor, intensely involved in the child’s education due to severe academic competition. Although this image of the Japanese mother is a stereotype spread by the popular mass media in Japan and abroad, and the extent by which Japanese mothers are absorbed in their children is exaggerated (Benjamin, 1997, p. 16; Cummings, 1989, p. 297; Stevenson & Stigler, 1992, p. 82), Stevenson and Stigler (1992) argue that Japanese parents do play an indispensable role in the academic performance of their children. During their longitudinal and cross-national research project, they and their collaborators observed that Japanese first and fifth graders persistently achieved higher on math tests than American children. Besides reciting teacher’s teaching style, cultural beliefs, and organization of schooling, Stevenson and Stigler (1992) mention parent’s role in supporting the learning conditions of the child to explain differences in achievement between elementary school students of the United States and students of Japan. In Japan, children receive more help at home with schoolwork (Chen & Stevenson, 1989; Stevenson & Stigler, 1992), and tend to perform less household chores than children in the USA (Stevenson et al., 1990; Stevenson & Stigler, 1992). More Japanese parents than American parents provide space and a personal desk and purchase workbooks for their children to supplement their regular text-books at school (Stevenson et al., 1990; Stevenson & Stigler, 1992). Additionally, Stevenson and Stigler (1992) observed that American mothers are much more readily satisfied with their child’s performance than Asian parents are, have less realistic assessments of their child’s academic perform ance, intelligence, and other personality characteristics, and subsequently have lower standards. Based on their observation of Japanese, Chinese and American parents, children and teachers, Stevenson and Stigler (1992) conclude that American families can increase the academic achievement of their children by strengthening the link between school and home, creating a physical and psychological environment that is conducive to study, and by making realistic assessments and raising standards. Also Benjamin (1997), who performed ‘day-to-day ethnography’ to find out how differences in practice between American and Japanese schools affect differences in outcomes, discusses the relationship between home and school and how the Japanese mother is involved in the academic performance standards reached by Japanese children. She argues that Japanese parents are willing to pay noticeable amounts of money for tutoring in commercial establishments to improve the child’s performance on entrance examinations, to assist in ho mework assignments, to facilitate and support their children’s participation in school requirements and activities, and to check notebooks of teachers on the child’s progress and other school-related messages from the teacher. These booklets are read and written daily by teachers and parents. Teachers regularly provide advice and reminders to parents, and write about homework assignments of the child, special activities and the child’s behavior (Benjamin, 1997, p. 119, p. 1993–1995). Newsletters, parents’ v isits to school, school reports, home visits by the teacher and observation days sustain communication in later years at school. According toBenjamin (1997), schools also inform parents about how to coach their children on proper behavior at home. Shimahara (1986), Hess and Azuma (1991), Lynn (1988) and White (1987) also try to explain national differences in educational achievement. They argue that Japanese mothers succeed in internalizing into their children academic expectations and adaptive dispositions that facilitate an effective teaching strategy, and in socializing the child into a successful person devoted to hard work.Support, Support and SupportEpstein (1995) constructed a framework of six types of involvement of parents and the community in the school: (1) parenting: schools help all families establish home environments to support children as students; (2) communicating: effective forms of school-to-home and home-to-school communications about school programs and children’s progress; (3) volu nteering: schools recruit and organize parents help and support; (4) learning at home: schools provide information and ideas to families about how to help students at home with homework and other curriculum-related activities, decisions and planning; (5) decision making: schools include parents in school decisions, develop parent leaders and representatives; and (6) collaborating with the community: schools integrate resources and services from the community to strengthen school programs, family practices, and student learning and development. All types of involvement mentioned in studies of Japanese education and in the discourse on the roots of the achievement gap belong to one of Epstein’s first four types of involvement: the creation of a conducive learn ing environment (type 4), the expression of high expectations (type 4), assistance in homework (type 4), teachers’ notebooks (type 2), mother’s willingness to facilitate school activities (type3) teachers’ advice about the child’s behavior (type 1), observ ation days by which parents observe their child in the classroom (type 2), and home visits by the teachers (type 1). Thus, when one carefully reads Stevenson and Stigler’s, Benjamin’s and other’s writings about Japanese education and Japanese students’ high achievement level, one notices that parents’ role in the child’s school learning is in particular one of support, expected and solicited by the school. The fifth type (decision making) as well as the sixth type (community involvement) is hardly ever mentioned in the discourse on the achievement gap.In 1997, the OECD’s Center for Educational Research and Innovation conducted a cross-national study to report the actual state of parents as partners in schooling in nine countries, including Japan. In its report, OECD concludes that the involvement of Japanese parents in their schools is strictly limited, and that the basis on which it takes place tends to be controlled by the teacher (OECD, 1997, p. 167). According to OECD (1997), many countries are currently adopting policies to involve families closely in the education of their children because (1) governments are decentralizing their administrations; (2) parents want to be increasingly involved; and (3) because parental involvement is said to be associated with higher achievement in school (p. 9). However, parents in Japan, where students already score highly on international achievement tests, are hardly involved in governance at the national and local level, and communication between school and family tends to be one-way (Benjamin, 1997; Fujita, 1989; OECD, 1997). Also parent–teacher associations (PTA, fubo to kyoshi no kai ) are primarily presumed to be supportive of school learning and not to participate in school governance (cf. OECD, 2001, p. 121). On the directionsof the occupying forces after the second world war, PTA were established in Japanese schools and were considered with the elective education boards to provide parents and the community an opportunity to participate actively in school learning (Hiroki, 1996, p. 88; Nakata, 1996, p. 139). The establishment of PTA and elective education boards are only two examples of numerous reform measures the occupying forces took to decentralize the formal education system and to expand educational opportunities. But after they left the country, the Japanese government was quick to undo liberal education reform measures and reduced the community and parental role in education. The stipulation that PTA should not interfere with personnel and other administrative tasks of schools, and the replacement of elective education boards by appointed ones, let local education boards believe that parents should not get involved with school education at all (Hiroki, 1996, p. 88). Teachers were regarded to be the experts and the parents to be the laymen in education (Hiroki, 1996, p. 89).In sum, studies of Japanese education point into one direction: parental involvement means being supportive, and community involvement is hardly an issue at all. But what is the actual state of parent and community involvement in Japanese schools? Are these descriptions supported by quantitative data?Statistics on Parental and Community InvolvementTo date, statistics of parental and community involvement are rare. How-ever, the school questionnaire of the TIMSS-R study did include some interesting questions that give us a clue about the degree of involvement relatively compared to the degree of involvement in other industrialized countries. The TIMSS-R study measured science and math achievement of eighth graders in 38 countries. Additionally, a survey was held among principals, teachers and students. Principals answered questions relating to school management, school characteristics, and involvement. For convenience, the results of Japan are only compared with the results of those countries with a GNP of 20650 US dollars or higher according to World Bank’s indicators in 1999.Unfortunately, only a very few items on community involvement were measured. According to the data, Japanese principals spend on average almost eight hours per month on representing the school in the community (Table I). Australian and Belgian principals spend slightly more hours and Dutch and Singaporean principals spend slightly less on representing the school and sustaining communication with the community. But when it comes to participation from the community, Japanese schools report a nearly absence of involvement (Table II). Religious groups and the business community have hardly any influence on the curriculum of the school. In contrast, half of the principals report that parents do have an impact in Japan. On one hand, this seems a surprising result when one is reminded of the centralized control of the Ministry of Education. Moreover, this control and the resulting uniform curriculum are often cited as a potential explanation of the high achievement levels in Japan. On the other hand, this extent of parental impact on the curriculum might be an indicator of the pressure parents put on schools to prepare their children appropriately for the entrance exams of senior high schools.In Table III, data on the extent of other types of parental involvement in Japan and other countries are given. In Japan, parental involvement is most common in case of schools volunteering for school projects and programs, and schools expecting parents to make sure that thechild completes his or her homework. The former is together with patrolling the grounds of the school to monitor student behavior most likely materialized through the PTA. The kinds and degree of activities of PTA vary according to the school, but the activities of the most active and well-organized PTA’s of 395 elementary schools investigated by Sumida (2001)range from facilitating sport and recreation for children, teaching greetings, encouraging safe traffic, patrolling the neighborhood, publishing the PTA newspaper to cleaning the school grounds (pp. 289–350). Surprisingly, less Japanese principals expect from the parents to check one’s child’s completion of homework than principals of other countries. In the discourse on the achievement gap, western observers report that parents and families in Japan provide more assistance with their children’s homework than parents and families outside Japan. This apparent contradiction might be the result of the fact that these data are measured at the lower secondary level while investigations of the roots of Japanese students’ high achievement levels focus on childhood education and learning at primary schools. In fact, junior high school students are given less homework in Japan than their peers in other countries and less homework than elementary school students in Japan. Instead, Japanese junior high school students spend more time at cram schools. Finally, Japanese principals also report very low degrees of expectations toward parents with regard to serving as a teacher aid in the classroom, raising funds for the school, assisting teachers on trips, and serving on committees which select school personnel and review school finances. The latter two items measure participation in school governance.In other words, the data support by and large the descriptions of parental of community involvement in Japanese schooling. Parents are requested to be supportive, but not to mount the territory of the teacher nor to be actively involved in governance. Moreover, whilst Japanese principals spend a few hours per month on communication toward the community, involvement from the community with regard to the curriculum is nearly absent, reflecting the nearly absence of accounts of community involvement in studies on Japanese education. However, the reader needs to be reminded that these data are measured at the lower secondary educational level when participation by parents in schooling decreases (Epstein, 1995; OECD, 1997; Osakafu Kyoiku Iinkai, unpublished report). Additionally, the question remains what stakeholders think of the current state of involvement in schooling. Some interesting local data provided by the Osaka Prefecture Education Board shed a light on their opinion.ReferencesBenjamin, G. R. (1997). Japanese lessons. New York: New York University Press.Cave, P. (2003). Educational reform in Japan in the 1990s: ‘Individuality’ and other uncertainties. Comparative Education Review, 37(2), 173–191.Chen, C., & Stevenson, H. W. (1989). Homework: A cross-cultural examination. Child Development, 60(3), 551–561.Chuo Kyoiku Shingikai (1996). 21 seiki o tenbo shita wagakuni no kyoiku no arikata ni tsu-ite [First Report on the Model for Japanese Education in the Perspective of theCummings, W. K. (1989). The American perception of Japanese parative Education, 25(3), 293–302.Epstein, J. L. (1995). School/family/community partnerships. Phi Delta Kappan , 701–712.Fujita, M. (1989). It’s all mother’s fault: childcare and the socialization of working mothers in Japan. The Journal of Japanese Studies , 15(1), 67–91.Harnish, D. L. (1994). Supplemental education in Japan: juku schooling and its implication. Journal of Curriculum Studies , 26(3), 323–334.Hess, R. D., & Azuma, H. (1991). Cultural support for schooling, contrasts between Japanand the United States. Educational Researcher , 20(9), 2–8, 12.Hiroki, K. (1996). Kyoiku ni okeru kodomo, oya, kyoshi, kocho no kenri, gimukankei[Rights and duties of principals, teachers, parents and children in education. InT. Horio & T. Urano (Eds.), Soshiki toshite no gakko [School as an organization](pp. 79–100). Tokyo: Kashiwa Shobo. Ikeda, H. (2000). Chiiki no kyoiku kaikaku [Local education reform]. Osaka: Kaiho Shup-pansha.Kudomi, Y., Hosogane, T., & Inui, A. (1999). The participation of students, parents and the community in promoting school autonomy: case studies in Japan. International Studies in Sociology of Education, 9(3), 275–291.Lynn, R. (1988).Educational achievement in Japan. London: MacMillan Press.Martin, M. O., Mullis, I. V. S., Gonzalez, E. J., Gregory, K. D., Smith, T. A., Chrostowski,S. J., Garden, R. A., & O’Connor, K. M. (2000). TIMSS 1999 Intern ational science report, findings from IEA’s Repeat of the Third International Mathematics and ScienceStudy at the Eight Grade.Chestnut Hill: The International Study Center.Mullis, I. V. S., Martin, M. O., Gonzalez, E. J., Gregory, K. D., Garden, R. A., O’Connor, K. M.,Chrostowski, S. J., & Smith, T. A.. (2000). TIMSS 1999 International mathemat-ics report, findings from IEA’s Repeat of the Third International Mathematics and Science Study at the Eight Grade.Chestnut Hill: The International Study Center. Ministry of Education, Science, Sports and Culture (2000).Japanese government policies in education, science, sports and culture. 1999, educational reform in progress. Tokyo: PrintingBureau, Ministry of Finance.Monbusho Ed. (1999).Heisei 11 nendo, wagakuni no bunkyoshisaku : Susumu kaikaku [Japanese government policies in education, science, sports and culture 1999: Educational reform in progress]. Tokyo: Monbusho.Educational Research for Policy and Practice (2004) 3: 95–107 © Springer 2005DOI 10.1007/s10671-004-5557-6Heidi KnipprathDepartment of MethodologySchool of Business, Public Administration and TechnologyUniversity of Twente P.O. Box 2177500 AE Enschede, The Netherlands译文:家长和社区在日本儿童教育中的作用摘要在日本,人们越来越关心家庭和社区参与到儿童教育中。
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毕业设计说明书英文文献及中文翻译学院:专2011年6月电子与计算机科学技术软件工程 Overview is a unified Web development model that includes the services necessary for you to build enterprise-class Web applications with a minimum of is part of Framework,and when coding applications you have access to classes in Framework.You can code your applications in any language compatible with the common language runtime(CLR), including Microsoft Visual Basic and C#.These languages enable you to develop applications that benefit from the common language runtime,type safety, inheritance,and so on.If you want to try ,you can install Visual Web Developer Express using the Microsoft Web Platform Installer,which is a free tool that makes it simple to download,install,and service components of the Microsoft Web Platform.These components include Visual Web Developer Express,Internet Information Services (IIS),SQL Server Express,and Framework.All of these are tools that you use to create Web applications.You can also use the Microsoft Web Platform Installer to install open-source and PHP Web applications.Visual Web DeveloperVisual Web Developer is a full-featured development environment for creating Web applications.Visual Web Developer provides an ideal environment in which to build Web sites and then publish them to a hosting ing the development tools in Visual Web Developer,you can develop Web pages on your own computer.Visual Web Developer includes a local Web server that provides all the features you need to test and debug Web pages,without requiring Internet Information Services(IIS)to be installed.Visual Web Developer provides an ideal environment in which to build Web sites and then publish them to a hosting ing the development tools in Visual Web Developer,you can develop Web pages on your own computer.Visual Web Developer includes a local Web server that provides all the features you need to test and debug Web pages,without requiring Internet Information Services(IIS)to be installed.When your site is ready,you can publish it to the host computer using the built-in Copy Web tool,which transfers your files when you are ready to share them with others.Alternatively,you can precompile and deploy a Web site by using the Build Web Site command.The Build Web Site command runs the compiler over the entire Web site(not just the code files)and produces a Web site layout that you can deploy to a production server.Finally,you can take advantage of the built-in support for File Transfer Protocol (FTP).Using the FTP capabilities of Visual Web Developer,you can connect directly to the host computer and then create and edit files on the server. Web Sites and Web Application ProjectsUsing Visual Studio tools,you can create different types of projects, which includes Web sites,Web applications,Web services,and AJAX server controls.There is a difference between Web site projects and Web application projects. Some features work only with Web application projects,such as MVC and certain tools for automating Web deployment.Other features,such as Dynamic Data,work with both Web sites and Web application projects.Page and Controls FrameworkThe page and controls framework is a programming framework that runs on a Web server to dynamically produce and render Web pages. Web pages can be requested from any browser or client device,and renders markup(such as HTML)to the requesting browser.As a rule,youcan use the same page for multiple browsers,because renders the appropriate markup for the browser making the request.However,you can design your Web page to target a specific browser and take advantage of the features of that browser. Web pages are completely object-oriented.Within Web pages you can work with HTML elements using properties,methods,and events.The page framework removes the implementation details of the separation of client and server inherent in Web-based applications by presenting a unified model for responding to client events in code that runs at the server.The framework also automatically maintains the state of a page and the controls on that page during the page processing life cycle.The page and controls framework also enables you to encapsulate common UI functionality in easy-to-use,reusable controls.Controls are written once, can be used in many pages,and are integrated into the Web page that they are placed in during rendering.The page and controls framework also provides features to control the overall look and feel of your Web site via themes and skins.You can define themes and skins and then apply them at a page level or at a control level.In addition to themes,you can define master pages that you use to create a consistent layout for the pages in your application.A single master page defines the layout and standard behavior that you want for all the pages(or a group of pages)in your application.You can then create individual content pages that contain the page-specific content you want to display.When users request the content pages,they merge with the master page to produce output that combines the layout of the master page with the content from the content page.The page framework also enables you to define the pattern for URLs that will be used in your site.This helps with search engine optimization(SEO)and makes URLs more user-friendly.The page and control framework is designed to generate HTML that conforms to accessibility guidelines. CompilerAll code is compiled,which enables strong typing,performance optimizations,and early binding,among other benefits.Once the code has been compiled,the common language runtime further compiles code to native code,providing improved performance. includes a compiler that will compile all your application components including pages and controls into an assembly that the hosting environment can then use to service user requests.Security InfrastructureIn addition to the security features , provides an advanced security infrastructure for authenticating and authorizing user access as well as performing other security-related tasks.You can authenticate users using Windows authentication supplied by IIS,or you can manage authentication using your own user database using forms authentication and membership. Additionally,you can manage the authorization to the capabilities and information of your Web application using Windows groups or your own custom role database using roles.You can easily remove,add to,or replace these schemes depending upon the needs of your application. always runs with a particular Windows identity so you can secure your application using Windows capabilities such as NTFS Access Control Lists(ACLs), database permissions,and so on.State-Management Facilities provides intrinsic state management functionality that enables you to store information between page requests,such as customer information or the contentsof a shopping cart.You can save and manage application-specific,session-specific, page-specific,user-specific,and developer-defined information.This information can be independent of any controls on the page. offers distributed state facilities,which enable you to manage state information across multiple instances of the same application on one computer or on several computers. Configuration applications use a configuration system that enables you to define configuration settings for your Web server,for a Web site,or for individual configuration settings are stored in XML-based files.Because these XML files are text files,it is simple to make configuration changes to your Web applications.Health Monitoring and Performance Features includes features that enable you to monitor health and performance of your health monitoring enables reporting of key events that provide information about the health of an application and about error conditions.These events show a combination of diagnostics and monitoring characteristics and offer a high degree of flexibility in terms of what is logged and how it is logged. supports two groups of performance counters available to your applications:The system performance counter group、The application performance counter group.Debugging Support takes advantage of the run-time debugging infrastructure to provide cross-language and cross-computer debugging support.You can debug both managedand unmanaged objects,in addition to all languages supported by the common language runtime and script languages.In addition,the page framework provides a trace mode that enables you to insert instrumentation messages into your Web pages.Web Services Framework supports XML Web services.An XML Web service is a component that contains business functionality that enables applications to exchange information across firewalls by using standards like HTTP and XML messaging.XML Web services are not tied to a particular component technology or object-calling convention.As a result,programs written in any language,using any component model,and running on any operating system can access XML Web services.Extensible Hosting Environment and Application Life-Cycle Management includes an extensible hosting environment that controls the life cycle of an application from when a user first accesses a resource(such as a page)in the application to the point at which the application is shut down.While relies on a Web server(IIS)as an application host, provides much of the hosting functionality itself.The architecture of enables you to respond to application events and create custom HTTP handlers and HTTP modules.Extensible Designer Environment includes enhanced support for creating designers for Web server controls for use with a visual design tool such as Visual Studio.Designers enable you to build a design-time user interface for a control,so that developers can configure your control's properties and content in the visual design tool.Web Applications Based on the MVC Pattern MVC helps Web developers build standards-based Web applications that are easy to maintain because it decreases the dependency among application layers by using the Model-View-Controller(MVC)pattern.It also provides complete control over the page MVC improves testability by supporting Test Driven Development(TDD). Dynamic Data Dynamic Data is a framework that lets you create data-driven Web applications easily.It does this by automatically discoveringdata-model metadata at run time and deriving UI behavior from it.A scaffolding framework provides a functional Web site for viewing and editing data.You can easily customize the scaffolding framework by changing elements or creating new ones to override the default behavior.Existing applications can easily integrate scaffolding elements together with pages.概述是一个统一的Web开发模型,它包括您使用尽可能少的代码生成企业级Web应用程序所必需的各种服务。