毕业设计外文翻译资料
毕业论文(设计)外文文献翻译及原文
金融体制、融资约束与投资——来自OECD的实证分析R．SemenovDepartment of Economics，University of Nijmegen，Nijmegen（荷兰内梅亨大学，经济学院）这篇论文考查了OECD的11个国家中现金流量对企业投资的影响.我们发现不同国家之间投资对企业内部可获取资金的敏感性具有显著差异,并且银企之间具有明显的紧密关系的国家的敏感性比银企之间具有公平关系的国家的低.同时，我们发现融资约束与整体金融发展指标不存在关系.我们的结论与资本市场信息和激励问题对企业投资具有重要作用这种观点一致，并且紧密的银企关系会减少这些问题从而增加企业获取外部融资的渠道。
一、引言各个国家的企业在显著不同的金融体制下运行。
金融发展水平的差别(例如，相对GDP的信用额度和相对GDP的相应股票市场的资本化程度），在所有者和管理者关系、企业和债权人的模式中，企业控制的市场活动水平可以很好地被记录.在完美资本市场,对于具有正的净现值投资机会的企业将一直获得资金。
然而，经济理论表明市场摩擦，诸如信息不对称和激励问题会使获得外部资本更加昂贵，并且具有盈利投资机会的企业不一定能够获取所需资本.这表明融资要素，例如内部产生资金数量、新债务和权益的可得性，共同决定了企业的投资决策.现今已经有大量考查外部资金可得性对投资决策的影响的实证资料（可参考，例如Fazzari（1998）、 Hoshi(1991)、 Chapman（1996）、Samuel(1998））.大多数研究结果表明金融变量例如现金流量有助于解释企业的投资水平。
这项研究结果解释表明企业投资受限于外部资金的可得性。
很多模型强调运行正常的金融中介和金融市场有助于改善信息不对称和交易成本，减缓不对称问题,从而促使储蓄资金投着长期和高回报的项目,并且提高资源的有效配置（参看Levine（1997)的评论文章）。
因而我们预期用于更加发达的金融体制的国家的企业将更容易获得外部融资.几位学者已经指出建立企业和金融中介机构可进一步缓解金融市场摩擦。
毕业设计外文翻译译文
1 工程概论1.1 工程专业1.2 工业和技术1.3 现代制造业工程专业1 工程行业是历史上最古老的行业之一。
如果没有在广阔工程领域中应用的那些技术，我们现在的文明绝不会前进。
第一位把岩石凿削成箭和矛的工具匠是现代机械工程师的鼻祖。
那些发现地球上的金属并找到冶炼和使用金属的方法的工匠们是采矿和冶金工程师的先祖。
那些发明了灌溉系统并建造了远古世纪非凡的建筑物的技师是他们那个时代的土木工程师。
2 工程一般被定义为理论科学的实际应用，例如物理和数学。
许多早期的工程设计分支不是基于科学而是经验信息，这些经验信息取决于观察和经历，而不是理论知识。
这是一个倾斜面实际应用的例子，虽然这个概念没有被确切的理解，但是它可以被量化或者数字化的表达出来。
3 从16、17世纪当代初期，量化就已经成为科学知识大爆炸的首要原因之一。
另外一个重要因素是实验法验证理论的发展。
量化包含了把来源于实验的数据和信息转变成确切的数学术语。
这更加强调了数学是现代工程学的语言。
4 从19世纪开始，它的结果的实际而科学的应用已经逐步上升。
机械工程师现在有精确的能力去计算来源于许多不同机构之间错综复杂的相互作用的机械优势。
他拥有能一起工作的既新型又强硬的材料和巨大的新能源。
工业革命开始于使用水和蒸汽一起工作。
从此使用电、汽油和其他能源作动力的机器变得如此广泛以至于它们承担了世界上很大比例的工作。
5 科学知识迅速膨胀的结果之一就是科学和工程专业的数量的增加。
到19世纪末不仅机械、土木、矿业、冶金工程被建立而且更新的化学和电气工程专业出现了。
这种膨胀现象一直持续到现在。
我们现在拥有了核能、石油、航天航空空间以及电气工程等。
每种工程领域之内都有细分。
6 例如，土木工程自身领域之内有如下细分：涉及永久性结构的建筑工程、涉及水或其他液体流动与控制系统的水利工程、涉及供水、净化、排水系统的研究的环境工程。
机械工程主要的细分是工业工程，它涉及的是错综复杂的机械系统，这些系统是工业上的，而非单独的机器。
毕业设计论文外文文献翻译
毕业设计(论文）外文文献翻译院系：财务与会计学院年级专业：201＊级财务管理姓名:学号：132148*＊*附件: 财务风险管理【Abstract】Although financial risk has increased significantly in recent years risk and risk management are not contemporary issues。
The result of increasingly global markets is that risk may originate with events thousands of miles away that have nothing to do with the domestic market。
Information is available instantaneously which means that change and subsequent market reactions occur very quickly。
The economic climate and markets can be affected very quickly by changes in exchange rates interest rates and commodity prices。
Counterparties can rapidly become problematic。
As a result it is important to ensure financial risks are identified and managed appropriately. Preparation is a key component of risk management。
【Key Words】Financial risk，Risk management，YieldsI. Financial risks arising1.1What Is Risk1.1.1The concept of riskRisk provides the basis for opportunity. The terms risk and exposure have subtle differences in their meaning. Risk refers to the probability of loss while exposure is the possibility of loss although they are often used interchangeably。
毕设设计类外文翻译
Interior Design Supports Art Education: A Case StudyInterior design, as a field of study, is a rapidly growing area of interest – particularly for teenagers in the United States. Part of this interest stems from the proliferation ofdesign-related reality shows available through television media. Some art educators and curriculum specialists in the nation perceive the study of interior spaces as a ‘practical application’ of the arts.This article discusses an experiential design problem, originally used in higher education interior design studio courses that was modified and shared with students in third grade to address national academic standards. Later, this same project was modified for use with high school students in the educator’s community a nd with international design students in South Korea.Lastly, the project was presented in a workshop to art education students at a higher education institution. The project was modified to address (1) the age group level and (2) a topic relevant to the audience. Goals of the design project were: (1) to explore creative problem-solving, (2) to explore the application of design elements and principles, and (3) to increase student understanding of spatial relationships within an interior environment. Findings indicate that the project supported several visual art standards, including perception and community. This project may be of interest to current and future art educators and others interested in the potential of interior design content supporting art education.IntroductionThe design of interior spaces is a growing area of interest in the United States. Studies indicate that people spend 90 per cent of their time indoors, thereby making the quality design of interiors critical to the health and welfare of the population. Youth have been unconsciously encouraged since their childhood to develop awareness of their personal interior spaces and furnishings through popular storybooks they read that introduce the awareness of scale, proportion and ergonomics at a very young age (e.g. Three Little Bears and Alice in Wonderland). More recently, teens in the United States have become unexpectedly ‘hooked’ on design related reality shows such as Trading Spaces, Changing Rooms and Design on a Dime. Although Trading Spaces was originally intended for adults, according to the Wall Street Journal article titled ‘The Teen-Room Makeover’ (18 October 2002) the audience has more than 125,000 viewers aged 12 to 17 [1]. In support of that finding, a survey conducted in 2003 for a national chain of hardware stores discovered 65 per cent of teens said they have watched home improvement-related television shows [2].Teens seemingly have a growing interest in the design of interior spaces.In the United States in 2002, a qualitative study was developed to determine if interior design subject-matter could support national academic standards in elementary and secondary schools (kindergarten – twelfth grade) [3]. Findings of the study indicated that art educators and curriculum specialists perceived interior design to be supportive in meeting their standards as a type of ‘practical application’ of the arts. Perceptions of the curriculum specialists indicated they were looking for new ways to interpret fine art standards in their existing curriculum and that interior design offered one solution. As a result, the researcher, who was an interior design educator, was encouraged to identify and develop a project or lesson plan that could introduce children and youth to the importance of well-designed interior spaces yet support an art education standard in the nation.This article discusses an experiential interior design project that was modified from an exercise used in the freshman and sophomore college studio classes and shared with students in third grade, high school, and with international students in South Korea by this interior design educator. The educator was later invited to present this project to art education teachers at her university. The project supported several school district visual art standards, including perception and community. It was modified to address (1) the age group level and (2) a topic relevant to the audience. Goals of the design project were: (1) to explore creative problem solving, (2) to explore the application of design elements and principles, and (3) to increase student understanding of spatial relationships within an interior environment. This project may be of interest to current and future art educators and others interested in the potential of interior design content supporting visual art standards.Review of literatureThe review of literature briefly discusses (1) experiential learning theory, (2) findings from a qualitative study involving art educators, and (3) the interior design link with art education. The interior design project description and process of application will follow.Experiential learningExperiential learning theory, as an application of cognitive/perceptual models, is a tool toenhance the cognitive process of students. Specifically, the experiential learning cycleinvolves a concrete experience that leads to observations and reflections then to formation of abstract concepts and generalisations, before finally testing implications from concepts in new situations [4].The Association for Experiential Education defines experiential education astheprocess by which a learner constructs knowledge, skill and value from direct experience [5]. Drengson [6] defines experiential education as the process of practical engagement withconcepts and skills applied in a practical setting and delivered through physical and practical mental activity.One of the key components to enhance student learning is reflection. Dewey [7] suggests that to have meaning, an experience must be combined with thought. Kolb [8] suggests that reflections can offer a potential source of powerful data to link theory to practice. The mental engagement of an experiential learner can involve questioning, investigation, experimentation, curiosity, problem-solving, assuming responsibility, creativity and the construction of meaning [9].Experiential learning offers the spontaneous opportunity for learning, whether from unplanned moments, natural consequences, mistakes or successes [10]. Holistically, it involves not only the cognitive but also any combination of the senses, the emotions, and the physical [11].Qualitative study involving art educatorsIn 2001, a study was conducted to determine if interior design may be supportive tokindergarten – twelfth grade (K–12) teachers in meeting national academic standards,including the arts [12]. To understand perceptions of experts in interior design and elementary and secondary education, five focus group session sand six personal interviews were conducted with interior design educators, practitioners,K–12 teachers (elementary, junior high, and high school levels), national standards curriculum specialists (local and state level), and school-to-career curriculum specialists from June 2001 to April 2002[13].Focus group findings indicated that K–12teachers, at both elementary and secondary levels, felt that interior design could be supportive in meeting visual art standards because youth are frequently analysing their personal and public spaces. Participants described specific examples of interior design materials they currently needed in their course work to include: examples of good and bad interior spaces, information about elements and principles of design as they relate to interior spaces, and hands-on col our wheels of sturdy materials. In addition they requested that the materials be low cost, stimulating,‘touchable’,recyclable, self-contained, and fun. Lesson plans the visual art teachers suggested included:• reinvention of the ‘shoe box’ projec t;• development of well-known stories (The Three Pigs, Three Little Bears, and Alice in Wonderland) into space models to teach proportion and scale. In addition, it was suggestedthe following lesson plan: use of Goldilocks story to analyse ‘client or consumer needs’;• use of a Dr Seuss story (literary passage) to generate a conceptual model that enhances creativity;• study of cultural spaces at the junior high level that would enhance study of personal expression of identity in interiors [14].The visual arts curriculum specialists indicated hat interior design –as a ‘practical application’ should be introduced in elementary levels where there is a ‘small window of opportunity’ to give good information about the visual arts. See Table 1 fo r an example of the visual art standards in kindergarten – third grade levels. One visual art specialist advocated that the design process was more important to teach than a particular design method. He suggested moving students from designing personal spaces – and the study of elements and principles of design – in elementary levels to the analysis of private and public spaces in the junior high level. Then the high school levels could be reserved for additional indepth Exploration.Today, junior high and high school students are quite attracted to design-related reality shows. Over the last five years, the number of designrelated television shows has increased dramatically [15]. Why are these shows so attractive to teens and young adults? Rodriguez [16]has suggested that this interest is linked to the teens need for expression of self andself-identity.An individual’s unique identity is established through personalisation of space, which is critical to overall development of self [17]. Developing a sense of self involves the use of symbols to communicate to others one’s personal underlying identity.Interior design link with art educationIt is not common for interior design to be linked with art education in K–12 grade levels in the United States. However, the Foundation for Interior Design EducationResearch[18]standards and guidelines – the accreditation organization for higher education interior design programmes in the nation – reveal that there are many shared areas between visual arts and interior design (e.g.elements and principles of design).Rasmussen and Wright [19]advocate the need for a new model for art education. The new model should offer youth an aesthetic education that does more than just serve the traditional concerns of established arts curriculum. Experiences indicate that young people try to make sense of their own lives by creating contextual understanding through actively, and intentionally, making connections to signs, perceptions and experiences. This is a challenge to develop a new art education model that creates a balance between social andcontextual needs, knowledge of young people, and theaesthetic medium itself.The study of interior spaces offers one such context for learning in the physical environment.People spend 90 per cent of their time in interior spaces [20]. Youth consciously or unconsciously, analyse and respond to their near environment. They also learn best if they understand why they are learning what they are learning. Application of design and art to everyday life can assist in making connections in student learning, and develop more awareness of good design as well as an appreciation of the arts. Youth need theopportunity to learn more about design and human behavior so they can learn they have choices about how supportive their environments can be. Children can [determine] how design influences their behaviors; howdesign can be used to manipulate behavior; how design can encourage or discourage conversation, establish status, put people in power positions, increase or decrease anxiety [21].Therefore, based on (1) the experiential learning theoretical underpinnings, (2) recommendations made by art educators and curriculum specialists, and (3) a call for a new ways of teaching art education, an interior design educator at a higher education institution modified an experiential design project that involved the use of elements and principles of design and an opportunity for self-expression of personal spaces. The designproblem of the personal space was changed based on the grade level.Case study project descriptionAlthough art educators and curriculum specialists perceived that interior design content could be supportive to visual art standards, it was determined that a case study project needed to be developed and presented to various grade levels. It was also determined that a conceptual model of interior spaces should be used toenhance student creativity and exploration rather than a finite model that would offer too many rules and boundaries. Project descriptionThe experiential interior design project involved the construction of athree-dimensional concept model using 44 triangular and rectangular pieces of cardstock (stiff) paper in a neutral colour [22]. The objective was to discover, manipulate and create interior spaces based on a given design problem (e.g. design your space station on a planet of your choice or design your home in the Rocky Mountains of Colorado). The purpose ofthe project was to encourage students to design a conceptual structure from the interior out, keep-ing in mind the function of the building. The student’s model had to incorporate a minimum of six spaces and three levels to encourage vertical as well as horizontal volumes. All 44 pieces of cardstock had to be used in the finished model, which sometimes posed achallenge to the youth. The cardstock pieces could not be ripped, torn, or pierced. However, they could be bent and shapedaccording to the whim of the student.Flow from one space to another and one level to another was emphasized. The decision-making design process was explained and encouraged.Outcomes consisted of a three-dimensional abstract model which, if successfully executed, demonstrated the break-down of traditional spatial paradigms. Design problemsEach student grade level was given a different design problem based on the academic standards that were to be met in that class. In some cases, several academic standards were addressed at the same time. Two national standards for visual arts in the United States were selected to be supported with this project: communication and perception. The communication standard indicates that students in kindergarten – third grade should recognise the use of the visual arts as a means of communication (e.g. select and use visual images, themes and ideas in their own work). The perception standard indicates that students know, understand and apply elements of visual arts and principles of design (e.g. Identify elements and principles of design).Third grade studentsAfter procuring appropriate permission, the design educator brought volunteer college-age interior design students to the elementary school to help administer the project. Three third grade classes (twenty students in each class) had just finished a science unit on space and orbits and were studying specific visual art standards. The children were asked to design a personal space station on a planet of their choice. The goal was to help students relate the newly learned science information to something in real life (e.g. Their home), yet encourage exploration of visual arts (see Figs. 2–4).Each team of students was given the same 44 pieces of cardstock (all cut out) in a plastic bag, a cardboard base (15” x 15” square) on which to build the model, and cellophane tape to use in constructing the model. To enhance reflection of this experiential project, each team of three students was asked to give a two-minute verbal presentation in front of the class on their finished model. In this manner, they could discuss their design solution and the design educator could assess their use of creativity through design elements and principles.The college students and design educator rotated through the three classrooms of students to answer questions, encourage use of design elements and principles, and applaud their creative exploration. The third grade teachers assisted in supporting the structure of the class and encouraging shy students who were reluctant to begin.It was interesting to observe that the children rarely built the models on their provided classroom tables. Instead,they moved to the floor space, located the base for the model in between team members, and began construction. Each team member assumed a role in the process. One team member seemed t o act as the ‘designer’, one as the ‘builder/construction crew’ and the last as the ‘supplier’ of materials. Students excitedlydiscussed the positioning of the triangular pieces of cardstock in their model, their rooms in their space stations, and the different ways to turn the model to create different vantage points.The teams of third graders had one hour to complete the models. Then their verbal presentations began, interspersed with questions and comments from the design educator and third grade teachers. Informal observations indicatedthat application of design elements and principles was strong – perhaps due to the consistent rectangular and triangular shapes that had been provided – thereby supporting the visual arts perception standard. Manipulation of shapes was innovative. Line, shape and form were used to provide movement through adjoining spaces and offered a sense of verticality. Interior volumes were created that supported human behaveour in interior spaces. For example, one team’s presentation discussed how their space station boasted an exercise room with trampolines to strengthen human muscles that weakened as a result of zero gravity in outer space. The communication standard was supported in their finished models in a couple ways. First there was a theme of design as it relates to protection from foreign objects. For example, one team’s space station on Saturn incorporated a force field to protect it from flying rocks. Other visual themes of security and safety evoked the implementation of security cameras, alien detectors, missile launchers, telescope laboratories, control stations and transport rooms. Another visual theme related to circulation. Circulation within the structure was depicted by the third graders through the use of escalators, stairs, elevators and poles. A third visual theme was unique human needs as they relate to interior spaces. Almost every team’s space station incorporated a room for their mothers! In addition, depending on the students’ personal interests, unique space station features ranged from chemical rooms to sandboxes. It was obvious in their multiple unique design solutions their use of creativity had been explored and enhanced.Evaluation and assessment that took place, after the classes were dismissed, indicated that the third grade teachers perceived that this experiential design project supported the visual arts standards in both the communication and perception components as well as the third grade science academic standard concerning space and orbits. In addition, the experiential component of the project had unexpected results when certain quiet, unassuming students in the class became animated and highly engaged in learning. One teacher shared her excitement with the design educator about a new connection that wasformed with one of students that she had not been able to connect with before the design exercise.High school studentsAfter the case study with the third grade students, it was determined to offer this project to high school students. Diversity students in a nearby community were invited to attend a complimentary design workshop at a local library. The interior design educator was asked to present a design problem that would relate to arteducation (see Figs. 6–8).Their problem was to use the same experiential project and shapes to design and construct a conceptual model of their new home or cabin in the Rocky Mountain region. The same project constraints existed. Due to the students’ ages, discussions took place prior to the exercise about innovative problem-solving, the exploration of creativity and the elements and principles of design used within the design process. Some of these elements and principles included:Scale. Awareness of human scale was addressed to develop understanding of proportion and scale of the structure and interior spaces. Shape. Triangular shapes were deliberately selected to encourage students to break paradigms of rectangular interior spaces.Colour. The cardstock pieces were of a neutral colour to enhance spatial composition rather than draw attention to colour usage or juxtaposition. Volume/Mass. The mass of thethree-dimensional model was important in communicating the use of common elements and principles of design (e.g. line, rhythm). Line. A variety of different lines (e.g. diagonal, horizontal) were investigated in the manipulation of the shapes. Space. Space was created through the manipulation of shapes. Theories of complexity, mystery and refuge within interior spaces were discussed. Informal assessment of the finished design models indicated that the design solutions werevery creative.Later that semester, by invitation, the same design project was taken to college students training to be art educators in a mini-workshop format. The art education students found the exercise effective in enhancing creativity and understanding how interior design can enhance understanding of visual arts.International studentsAlthough there was no intention to meet a national visual arts academic standard at a specific grade level, this same experiential design project was presented in Seoul, South Korea to college-aged international students. The design problem was to use the same 44 pieces to develop a design concept model for acommercial building in Seoul. Language translators were used to help the design educatorintroduce the project, guide the students through the process, and understand their verbal presentations at the end of the workshop.Students commented during and after the workshop how the model enhanced their visual literacy skills (they used different words) and creativity within the context of everyday life. The experiential nature of the workshop was seemingly a pleasure to them (see Figs.9–11).Discussion and conclusionThis interior design case study project was designed to be experiential in nature to enhance student learning of the visual arts. Student and teacher assessment of the various groups indicated enthusiasm for the design project because it enhanced creativity, explored multiple design solutions, related to real life, and increased their understanding of human behaviour within the context of the physical environment. Teacherassessment of the age groups indicated that the project did support visual art standards at the appropriate grade level. In addition, their assessment indicated satisfaction with the manner in which the interior design project encouraged student usage of the design elements and principles and the application of design to everyday living. Several instructors indicated that quiet and shy students in their class became engaged in the learning process, which had not been previously observed. Perception of art educators and art education students was that this project supported a variety of visual art standards such as perception and communication. This interior design case study project can be modified for various age and cultural groups and may be of interest to educators who are interested in working collaboratively with colleagues from other disciplines.Visual art programmes in the United States are being cut from the K–12 curriculum. By linking visual arts to an up-and-coming aesthetic field, such as interior design, there may be new ways to sustain and grow visual art programmes in the nation.References1. Orndoff, K. (2003) ASID American Society of Interior Designers 2003 Strategic Environment Report. Future Impact Education, p. 9.2. Levitz, S. (2004) Teens Hooked on Home Décor, London Free Press (Ontario, CA), 24 June, p. D2.3. Clemons, S. (2002) Collaborative Links with K–12: A Proposed Model Integrating Interior Design with National Education Standards, Journal of Interior Design, Vol. 28, No. 1, pp.40–8.4. Rubin, S. G. (1983) Overcoming Obstacles to Institutionalization of Experiential Learning Programs, New Directions for Experiential Learning, Vol. 20, pp. 43–54.5. Luckman, C. (1996) Defining Experiential Education, Journal of Experiential Education, Vol. 19, No. 1, pp. 6–7.6. Drengson, A. R. (1995) What Means this Experience? in Kraft, R. J. & Sokofs, M. [Eds] The Theory of Experiential Education. Boulder, CO: Association for Experiential Education, pp. 87–93.7. Dewey, J. (1916) Democracy and Education. New York: Macmillan.8. Kolb, D. A. (1984). Experiential Learning: Experience as the Sources of Learning and Development. Englewood Cliffs, NJ: Prentice-Hall.9. Luckmann, C. op. cit.10. Ibid.11. Carver, R. (1996) Theory for Practice: A Framework for Thinking about Experiential Education, Journal of Experiential Education, Vol. 19, No. 1, pp. 8–13.12. Clemons, S. op. cit.13. Ibid.14. Ibid.15. Bien, L. (2003) Renovating how-to TV Shows in a Race to Duplicate Success of ‘Trading Spaces’. The Post Standard (Syracuse, NY), 31 October, p. E1.16. Rodriguez, E. M. (2003) Starting Young, Miami Herald, 28 December, p. H–1.17. Baillie S. & Goeters, P. (1997) Home as a Developmental Environment. Proceedings of the American Association of Housing Educators, New Orleans, LA, pp. 32–6.18. Foundation of Interior Design Education Research (FIDER) home page. Available from URL: / (Accessed 4th January 2005).19. Rasmussen, B & Wright, P. (2001) The theatre workshop as educational space: How imagined reality is voiced and conceived, International Journal of Education & the Arts, Vol. 2, No. 2, pp.1–13.20. Environmental Protection Agency (2006) An Introduction to Indoor Air Quality (online). Available from URL: /iaq/ ia-intro.html (Accessed 26th September 2006).21. InformeDesign (n.d.) Implications, Vol. 1, No. 2, p. 2 (online). Available from URL: /# (Accessed 4th January 2005).22. Curfman, J. & Clemons, S. (1992) From Forty-Four Pieces to a New Spatial Paradigm, in Birdsong, C. [Ed.] Proceedings of the Interior Design Educators Council Southwest Regional Meeting, New Orleans, pp. 2–4./detail/refdetail?tablename=SJWD_U&filename=SJWD00000744102&uid=WEEvR EcwSlJHSldSdnQ0SWZDdUlMV1dWZi9tOGkyYTBaTzBVQjVYeENXYVp4MVRJQjI3cmZRYS9YRmhvdnlxazJRPT 0=$9A4hF_YAuvQ5obgVAqNKPCYcEjKensW4IQMovwHtwkF4VYPoHbKxJw!!Interior Design in Augmented Reality EnvironmentABSTRACTThis article presents an application of Augmented Realitytechnology for interior design. Plus, an Educational InteriorDesign Project is reviewed. Along with the dramatic progress ofdigital technology, virtual information techniques are alsorequired for architectural projects. Thus, the new technology ofAugmented Reality offers many advantages for digitalarchitectural design and construction fields. AR is also beingconsidered as a new design approach for interior design. In an ARenvironment, the virtual furniture can be displayed and modifiedin real-time on the screen, allowing the user to have an interactiveexperience with the virtual furniture in a real-world environment.Here, AR environment is exploited as the new workingenvironment for architects in architectural design works, and thenthey can do their work conveniently as such collaborativediscussion through AR environment. Finally, this study proposesa newmethod for applying AR technology to interior designwork, where a user can view virtual furniture and communicatewith 3D virtual furniture data using a dynamic and flexible userinterface. Plus, all the properties of the virtual furniture can beadjusted using occlusion- based interaction method for a TangibleAugmented Reality. General TermsApplications of computer science in modeling, visualization andmultimedia, graphics and imaging, computer vision, human-computerinteraction, et al.KeywordsAugmented Reality, Tangible AR, CAAD, ARToolKit, Interiordesign.1. INTRODUCTIONVisualizing how a particular table or chair will look in a roombefore it is decorated is a difficult challenge for anyone. Hence,Augmented Reality (AR) technology has been proposed forinterior design applications by few previous authors, for example,Koller, C. Wooward, A. Petrovski; K. Hirokazu, et al. The relateddevices typically include data glassesconnected to a。
毕业设计外文文献翻译范文
毕业设计外文文献翻译专业学生姓名班级学号指导教师优集学院外文资料名称：Knowledge-Based Engineeri--ng Design Methodology外文资料出处：Int.J.Engng Ed.Vol.16.No.1附件： 1.外文资料翻译译文2.外文原文基于知识工程(KBE)设计方法D. E. CALKINS1.背景复杂系统的发展需要很多工程和管理方面的知识、决策，它要满足很多竞争性的要求。
设计被认为是决定产品最终形态、成本、可靠性、市场接受程度的首要因素。
高级别的工程设计和分析过程(概念设计阶段)特别重要，因为大多数的生命周期成本和整体系统的质量都在这个阶段。
产品成本的压缩最可能发生在产品设计的最初阶段。
整个生命周期阶段大约百分之七十的成本花费在概念设计阶段结束时，缩短设计周期的关键是缩短概念设计阶段，这样同时也减少了工程的重新设计工作量。
工程权衡过程中采用良好的估计和非正式的启发进行概念设计。
传统CAD工具对概念设计阶段的支持非常有限。
有必要，进行涉及多个学科的交流合作来快速进行设计分析(包括性能，成本，可靠性等)。
最后，必须能够管理大量的特定领域的知识。
解决方案是在概念设计阶段包含进更过资源，通过消除重新设计来缩短整个产品的时间。
所有这些因素都主张采取综合设计工具和环境，以在早期的综合设计阶段提供帮助。
这种集成设计工具能够使由不同学科的工程师、设计者在面对复杂的需求和约束时能够对设计意图达成共识。
那个设计工具可以让设计团队研究在更高级别上的更多配置细节。
问题就是架构一个设计工具，以满足所有这些要求。
2.虚拟(数字)原型模型现在需要是一种代表产品设计为得到一将允许一产品的早发展和评价的真实事实上原型的过程的方式。
虚拟样机将取代传统的物理样机，并允许设计工程师，研究“假设”的情况，同时反复更新他们的设计。
真正的虚拟原型，不仅代表形状和形式，即几何形状，它也代表如重量，材料，性能和制造工艺的非几何属性。
本科毕业设计外文文献翻译
（Sheaｒ waｌl ｓt ｒuctural desigｎ ofh ｉgh-ｌev ｅl fr ａmeworkＷｕ Jiche ｎgＡbstract ： In t ｈis pape ｒ the basic c ｏｎcepts of ｍａn ｐow ｅr ｆｒom th ｅ ｆra ｍｅ sh ｅａr w ａｌl str ｕc ｔｕｒｅ, analy ｓis of the ｓtruct ｕr ａｌ des ｉgn ｏf th ｅ c ｏnt ｅnt ｏｆ t ｈe fr ａme she ａr wall, in ｃｌudi ｎg the ｓeism ｉc wa ｌl she ａr spa本科毕业设计外文文献翻译学校代码： 10128学 号：题 目：Shear wall structural design of high-level framework 学生姓名： 学 院：土木工程学院 系 别：建筑工程系 专 业：土木工程专业（建筑工程方向） 班 级：土木08-（5）班 指导教师： (副教授)ｎratiｏdesign, ａnd a concrｅtｅｓtruｃtuｒe in thｅmｏst co ｍmonｌy useｄframe shear walｌstｒｕcturｅtｈｅdesign of p ｏiｎｔs to note.Keyworｄs: cｏncrｅｔｅ; fｒaｍｅshｅａｒwall sｔｒucｔｕre；hiｇh－risｅbuildｉｎｇsThe wall is aｍoｄern high－rｉｓe buiｌdiｎgs is an iｍpo ｒｔant buiｌdinｇconｔｅnt, the ｓize of thｅfraｍe sheａr wall must comｐly with buildｉng reguｌａtｉons. The pｒｉnｃipｌe is ｔhat the largeｒsｉzｅbｕt the thｉｃknessｍuｓt ｂｅsmaller gｅoｍetric featｕrｅｓshoｕlｄｂe ｐｒeｓented ｔo the pｌatｅ,ｔｈe forｃe is close to cylｉndrｉcal.Ｔhe waｌl sｈｅar wa ｌl strｕｃｔure ｉs a flaｔcomｐonent. Itｓeｘposure to tｈe force aｌoｎg ｔhe ｐlane leｖｅl of theｒole ofｓｈear and momｅｎt, must also take ｉｎtｏａccounｔthe veｒｔical preｓsure.Opeｒate unｄer thｅcomｂiｎed actｉｏn oｆbenｄing momeｎts and axial force aｎｄsheａr forcｅbｙthe caｎtilｅｖｅr deep beａm uｎder ｔｈe acｔion of the force leveｌｔo lｏo ｋinto ｔｈe bottom mouｎted on ｔhe basｉs of. Sheaｒｗaｌl ｉｓdiｖidｅｄinｔo a whole walｌand ｔheａssoｃiated ｓｈeａr wall in thｅactual project,a wholｅwａlｌfor ｅxａmpl ｅ, suｃh as ｇenｅraｌhｏusiｎｇｃonstｒuction in tｈe gablｅｏr fish bｏne strｕcture ｆｉlｍwａｌls ａnd small opｅningｓwall.Cｏupled Sｈeａr ｗalls are ｃonnｅcted bｙｔhｅcｏupｌing ｂeam shｅａr wall.Buｔｂecause tｈeｇｅnerａlｃｏupling beaｍstｉｆfness is less thaｎｔhe wall stiｆfnｅsｓof the lｉmbs，ｓｏ. Wａlｌliｍb aｌonｅis obviｏus.The ｃｅntral beam of tｈeｉnflｅｃtion pｏｉnｔtｏpay aｔtenｔiｏｎto tｈeｗaｌl pressｕre thａn the limiｔs of the lｉmb axis. Will forｍa shortｗiｄe beａms，widｅcolｕmn wａll liｍｂｓhear wａll ｏpｅnings toｏlarge ｃomｐonｅnt aｔbothｅn ｄs ｗith jｕst the domain of vａｒiabｌe crosｓ－ｓecｔｉon ro ｄin ｔhe intｅrｎａｌforcｅｓｕnder tｈｅaｃtioｎof maｎy Ｗalｌlｉmb iｎflｅcｔion point Ｔhｅｒeｆoｒe, ｔhe cａｌcula ｔions ａｎd consｔruction sｈouldAccordinｇtｏappｒoxiｍａｔe tｈe framｅstｒucｔure to ｃonsideｒ.Tｈe desｉｇｎof ｓhｅａr walls ｓhoulｄbe based on the cｈａractｅrisｔics ｏf ａvａｒｉｅty oｆwall itseｌｆ,ａnd dｉfferｅnｔmeｃhanical ch ａrａcteｒisｔｉcｓand requireｍents,wall oｆthｅinternａｌforceｄistrｉbutｉon and failurｅmoｄｅs ｏf sｐecific and cｏmprehensive ｃonｓideration of the design rｅinｆorcemｅnt aｎd stｒuctural measｕres. Ｆrame sｈear wall ｓｔrｕctuｒe deｓiｇn is to cｏｎsider the ｓtructｕre of the oｖerall ａnａｌysis for ｂoｔh dｉrecｔｉｏｎsｏｆthｅhｏrｉzontal and vｅrtiｃalｅfｆects. Oｂtain thｅinternal force ｉs reｑuirｅd in ａccｏrdancｅｗｉｔｈtｈe bias or paｒtｉal ｐull normal sｅcｔｉon forｃｅｃaｌculatiｏn.The waｌl strｕcture oｆtheｆｒame sｈear ｗall ｓｔructural dｅsign of ｔhe coｎtent frame hｉgh-rise buildings, in ｔhe actual ｐrｏjeｃｔiｎｔhｅuse of thｅｍoｓt seisｍic ｗａlls have suffiｃient quantitｉeｓto meｅt ｔheｌｉmitsｏf the lａyer displacement, the loｃation iｓｒelａtiｖely flexiblｅ. Seiｓmic wａll for cｏntinuous layout，ｆulｌ-length ｔhroｕgh．Should bｅdesigned to avoid the waｌl mutaｔioｎs ｉn limb ｌｅｎgth and alignment is noｔuｐａnd down the ｈolｅ. The samｅtｉme．Tｈe inｓide of ｔhe hole marginｓcｏlｕｍｎshｏｕld not ｂｅｌｅssｔhan３00mm ｉｎordｅｒtｏguaraｎteｅtheｌengtｈof the colｕｍn ａs the edgｅof tｈe coｍponent and constｒａiｎt eｄgｅcｏｍponeｎts．Thｅbi-direc ｔiｏnal laｔerａl forｃe ｒesiｓting strucｔurａl fｏrm of verticａl aｎｄhorｉzontaｌwalｌcoｎnected.Eａｃh ｏｔhｅr as ｔhe ａffiｎiｔｙof the shｅar wall. Ｆor ｏnｅ, two seismic frａme sｈe ａr ｗalｌｓ,ｅｖen beam highｒatio ｓhould noｔgreateｒthan 5 aｎd a height of nｏt less thaｎ400mm.Midline colｕmnａnd beａmｓ,wall ｍｉdline shouｌdｎoｔbe greaｔer tha ｎthe ｃoｌｕmｎwidｔｈof1/4，ｉn ordｅr ｔｏreｄuce thｅtoｒsional eｆfect of the sｅiｓmｉｃacｔion ｏnｔｈｅｃolｕmn．Oｔhｅrwｉsｅcan be taken tｏstrengthｅn theｓtirruprａｔｉo iｎｔhe cｏlｕmn tｏmake ｕp.If thｅshear wａｌl sheａｒsｐａn ｔhａnｔhe ｂig twｏ. Ｅveｎthe beａｍcro ｓs-heｉｇht ratiｏgreateｒthan 2.5, ｔhen tｈe design presｓｕｒe ｏf thｅｃｕt shoulｄnoｔmａkｅａｂig 0.2. Howevｅｒ, ｉf the sheａｒwallｓheａr sｐａｎｒatiｏof ｌess than two couｐlinｇｂeａms sｐan of ｌeｓs than ２．5, then the shear coｍｐres ｓiｏn rａｔiｏis noｔgreaｔer thａn 0.15. Thｅｏther haｎｄ，ｔhe bｏttom oｆthe fraｍe ｓhｅar walｌstructure ｔo enhａnce tｈｅdｅsign sｈould ｎoｔbe leｓs thaｎ２０0mmａnd noｔlesｓthaｎstorey 1/１6，othｅｒｐaｒtｓｓhｏulｄnot be lｅss than 160mm ａnd ｎｏt ｌｅss thaｎｓtoｒey １/20. Arounｄthe wall of the frame ｓhｅar ｗall strucｔure sｈｏulｄbe set ｔo the beａm or dark bｅamａnd the sｉｄe columｎｔｏform a borｄｅr. Ｈoｒizｏntａl ｄｉｓtrｉbuｔioｎoｆsｈear waｌls cａn from the sheａr effect，tｈｉs design wｈen ｂuilｄｉng higｈｅr longeｒor fｒaｍｅｓtructｕre reinfoｒcｅment shｏuld be aｐprｏpｒiatelｙincｒeａｓed, ｅspｅcｉａlｌy in the sｅnｓitivｅｐarts of the beam pｏsition ｏr teｍperaｔuｒe, stiffnｅsｓchａnge is besｔappｒopriatｅly increased, ｔｈeｎcｏnsidｅration sｈoulｄbe ｇｉveｎｔo the wａlｌvertｉcaｌreiｎforｃemeｎt,becaｕse ｉt is mａinly fｒom the bｅnding efｆecｔ, aｎｄtake in ｓome ｍｕlti-ｓtorｅｙshｅａｒｗａll structuｒereinforcｅｄreｉnｆorceｍent rate -likｅlｅsｓconｓtｒained edgｅｏｆｔhｅcomｐonent or components reinforｃemeｎt of thｅedge ｃomｐｏnent.Referｅnces: [1 sad Hａyaｓhi,He Yaming. Ｏn the shorｔshｅar ｗall ｈigh-riｓe bｕilｄinｇｄesign ［J]．Kｅｙｕaｎ, 2008, (O2).高层框架剪力墙结构设计吴继成摘要: 本文从框架剪力墙结构设计的基本概念人手, 分析了框架剪力墙的构造设计内容, 包括抗震墙、剪跨比等的设计, 并出混凝土结构中最常用的框架剪力墙结构设计的注意要点。
毕业设计论文 外文文献翻译
毕业设计（论文）外文参考文献翻译计算机科学与信息工程系系（院）2008 届题目企业即时通Instant Messaging for Enterprises课题类型技术开发课题来源自选学生姓名许帅专业班级 04计算机科学与技术指导老师王占中职称工程师完成日期：2008年4 月 6 日目录I NSTANT M ESSAGING FOR E NTERPRISE (1)1. Tips (1)2. Introduction (1)3. First things first (2)4.The While-Accept loop (4)5. Per-Thread class (6)6. The Client class (7)企业即时通 (9)1.提示 (9)2.简介 (9)3.首先第一件事 (10)4.监听循环 (11)5.单线程类 (13)6.用户端类 (14)Instant Messaging for Enterprise1. TipsIf Java is, in fact, yet another computer programming language, you may question why it is so important and why it is being promoted as a revolutionary step in computer programming. The answer isn’t immediately obvious if you’re coming from a tr aditional programming perspective. Although Java is very useful for solving traditional standalone programming problems, it is also important because it will solve programming problems on the World Wide Web. What is the Web?The Web can seem a bit of a mys tery at first, with all this talk of “surfing,”“presence,” and “home pages.” It’s helpful to step back and see what it really is, but to do this you must understand client/server systems, another aspect of computing that is full of confusing issues. The primary idea of a client/server system is that you have a central repository of information，some kind of data, often in a database。
毕业设计(论文)外文资料翻译(学生用)
毕业设计外文资料翻译学院：信息科学与工程学院专业：软件工程姓名： XXXXX学号： XXXXXXXXX外文出处： Think In Java (用外文写)附件： 1.外文资料翻译译文；2.外文原文。
附件1：外文资料翻译译文网络编程历史上的网络编程都倾向于困难、复杂，而且极易出错。
程序员必须掌握与网络有关的大量细节，有时甚至要对硬件有深刻的认识。
一般地，我们需要理解连网协议中不同的“层”（Layer）。
而且对于每个连网库，一般都包含了数量众多的函数，分别涉及信息块的连接、打包和拆包；这些块的来回运输；以及握手等等。
这是一项令人痛苦的工作。
但是，连网本身的概念并不是很难。
我们想获得位于其他地方某台机器上的信息，并把它们移到这儿；或者相反。
这与读写文件非常相似，只是文件存在于远程机器上，而且远程机器有权决定如何处理我们请求或者发送的数据。
Java最出色的一个地方就是它的“无痛苦连网”概念。
有关连网的基层细节已被尽可能地提取出去，并隐藏在JVM以及Java的本机安装系统里进行控制。
我们使用的编程模型是一个文件的模型；事实上，网络连接（一个“套接字”）已被封装到系统对象里，所以可象对其他数据流那样采用同样的方法调用。
除此以外，在我们处理另一个连网问题——同时控制多个网络连接——的时候，Java内建的多线程机制也是十分方便的。
本章将用一系列易懂的例子解释Java的连网支持。
15.1 机器的标识当然，为了分辨来自别处的一台机器，以及为了保证自己连接的是希望的那台机器，必须有一种机制能独一无二地标识出网络内的每台机器。
早期网络只解决了如何在本地网络环境中为机器提供唯一的名字。
但Java面向的是整个因特网，这要求用一种机制对来自世界各地的机器进行标识。
为达到这个目的，我们采用了IP（互联网地址）的概念。
IP以两种形式存在着：(1) 大家最熟悉的DNS（域名服务）形式。
我自己的域名是。
所以假定我在自己的域内有一台名为Opus的计算机，它的域名就可以是。
毕业设计说明书外文翻译---时间和频率的基本原理
毕业设计说明书英文文献及中文翻译学院：信息与通信工程专业：电子信息科学与技术2011年 6月外文文献原文Fundamentals of Time and Frequency IntroductionTime and frequency standards supply three basic types of information：time-of-day，time interval，and frequency. Time-of-day information is provided in hours，minutes，and seconds，but often also includes the date (month，day，and year). A device that displays or records time-of-day information is called a clock. If a clock is used to label when an event happened，this label is sometimes called a time tag or time stamp. Date and time-of-day can also be used to ensure that events are synchronized，or happen at the same time.Time interval is the duration or elapsed time between two events. The standard unit of time interval is the second(s). However，many engineering applications require the measurement of shorter time intervals，such as milliseconds (1 ms = 10 -3 s) ，microseconds (1 μs = 10 -6 s) ，nanoseconds (1 ns = 10 -9 s) ，and picoseconds (1 ps = 10 -12 s). Time is one of the seven base physical quantities，and the second is one of seven base units defined in the International System of Units (SI). The definitions of many other physical quantities rely upon the definition of the second. The second was once defined based on the earth‟s rotational rate or as a fraction of the tropical year. That changed in 1967 when the era of atomic time keeping formally began. The current definition of the SI second is the duration of 9，192，631，770 periods of the radiation corresponding to the transition between two hyperfine levels of the ground state of the cesium-133 atom.Frequency is the rate of a repetitive event. If T is the period of a repetitive event，then the frequency f is its reciprocal，1/T. Conversely，the period is the reciprocal of the frequency，T = 1/f. Since the period is a time interval expressed in seconds (s) ，it is easy to see the close relationship between time interval and frequency. Thestandard unit for frequency is the hertz (Hz) ，defined as events or cycles per second. The frequency of electrical signals is often measured in multiples of hertz，including kilohertz (kHz)，megahertz (MHz)，or gigahertz (GHz)，where 1 kHz equals one thousand (103) events per second，1 MHz equals one million (106) events per second，and 1 GHz equals one billion (109) events per second. A device that produces frequency is called an oscillator. The process of setting multiple oscillators to the same frequency is called synchronization.Of course，the three types of time and frequency information are closely related. As mentioned，the standard unit of time interval is the second. By counting seconds，we can determine the date and the time-of-day. And by counting events or cycles per second，we can measure frequency.Time interval and frequency can now be measured with less uncertainty and more resolution than any other physical quantity. Today，the best time and frequency standards can realize the SI second with uncertainties of ≈1×10-15.Physical realizations of the other base SI units have much larger uncertainties.Coordinated Universal Time (UTC)The world‟s major metrology laboratories routinely measure their time and frequency standards and send the measurement data to the Bureau International des Poids et Measures (BIPM) in Sevres，France. The BIPM averages data collected from more than 200 atomic time and frequency standards located at more than 40 laboratories，including the National Institute of Standards and Technology (NIST). As a result of this averaging，the BIPM generates two time scales，International Atomic Time (TAI)，and Coordinated Universal Time (UTC). These time scales realize the SI second as closely as possible.UTC runs at the same frequency as TAI. However，it differs from TAI by an integral number of seconds. This difference increases when leap seconds occur. Whennecessary，leap seconds are added to UTC on either June 30 or December 31. The purpose of adding leap seconds is to keep atomic time (UTC) within ±0.9 s of an older time scale called UT1，which is based on the rotational rate of the earth. Leap seconds have been added to UTC at a rate of slightly less than once per year，beginning in 1972.Keep in mind that the BIPM maintains TAI and UTC as ……paper‟‟ time scales. The major metrology laboratories use the published data from the BIPM to steer their clocks and oscillators and generate real-time versions of UTC. Many of these laboratories distribute their versions of UTC via radio signals which section 17.4 are discussed in.You can think of UTC as the ultimate standard for time-of-day，time interval，and frequency. Clocks synchronized to UTC display the same hour minute，and second all over the world (and remain within one second of UT1). Oscillators simonized to UTC generate signals that serve as reference standards for time interval and frequency.Time and Frequency MeasurementTime and frequency measurements follow the conventions used in other areas of metrology. The frequency standard or clock being measured is called the device under test (DUT). A measurement compares the DUT to a standard or reference. The standard should outperform the DUT by a specified ratio，called the test uncertainty ratio (TUR). Ideally，the TUR should be 10：1 or higher. The higher the ratio，the less averaging is required to get valid measurement results.The test signal for time measurements is usually a pulse that occurs once per second (1 ps). The pulse width and polarity varies from device to device，but TTL levels are commonly used. The test signal for frequency measurements is usually at a frequency of 1 MHz or higher，with 5 or 10 MHz being common. Frequency signalsare usually sine waves，but can also be pulses or square waves if the frequency signal is an oscillating sine wave. This signal produces one cycle (360∞or 2πradians of phase) in one period. The signal amplitude is expressed in volts，and must be compatible with the measuring instrument. If the amplitude is too small，it might not be able to drive the measuring instrument. If the amplitude is too large，the signal must be attenuated to prevent overdriving the measuring instrument.This section examines the two main specifications of time and frequency measurements—accuracy and stability. It also discusses some instruments used to measure time and frequency.AccuracyAccuracy is the degree of conformity of a measured or calculated value to its definition. Accuracy is related to the offset from an ideal value. For example，time offset is the difference between a measured on-time pulse and an ideal on-time pulse that coincides exactly with UTC. Frequency offset is the difference between a measured frequency and an ideal frequency with zero uncertainty. This ideal frequency is called the nominal frequency.Time offset is usually measured with a time interval counter (TIC). A TIC has inputs for two signals. One signal starts the counter and the other signal stops it. The time interval between the start and stop signals is measured by counting cycles from the time base oscillator. The resolution of a low cost TIC is limited to the period of its time base. For example，a TIC with a 10-MHz time base oscillator would have a resolution of 100 ns. More elaborate Tics use interpolation schemes to detect parts of a time base cycle and have much higher resolution—1 ns resolution is commonplace，and 20 ps resolution is available.Frequency offset can be measured in either the frequency domain or time domain.A simple frequency domain measurement involves directly counting and displaying thefrequency output of the DUT with a frequency counter. The reference for this measuremen t is either the counter‟s internal time base oscillator ， or an external time base. The counter‟s resolution ， or the number of digits it can display ， limits its ability to measure frequency offset. For example ， a 9-digit frequency counter can detect a frequency offset no smaller than 0.1 Hz at 10 MHz (1×10-8). The frequency offset is determined asmeasure nominal nominal(f -f )f= f Where f measur is the reading from the frequency counter ， and f nominal is the frequency labeled on the oscillator‟s nameplate ， or specified output frequency.Frequency offset measurements in the time domain involve a phase comparison between the DUT and the reference. A simple phase comparison can be made with an oscilloscope. The oscilloscope will display two sine waves. The top sine wave represents a signal from the DUT ， and the bottom sine wave represents a signal from the reference. If the two frequencies were exactly the same ， their phase relationship would not change and both would appear to be stationary on the oscilloscope display. Since the two frequencies are not exactly the same ， the reference appears to be stationary and the DUT signal moves. By measuring the rate of motion of the DUT signal we can determine its frequency offset. Vertical lines have been drawn through the points where each sine wave passes through zero. The bottom of the figure shows bars whose width represents the phase difference between the signals. In this case the phase difference is increasing ， indicating that the DUT is lower in frequency than the reference.Measuring high accuracy signals with an oscilloscope is impractical ， since the phase relationship between signals changes very slowly and the resolution of the oscilloscope display is limited. More precise phase comparisons can be made with a TIC. If the two input signals have the same frequency ， the time interval will notchange. If the two signals have different frequencies ， the time interval wills change ， and the rate of change is the frequency offset. The resolution of a TIC determines the smallest frequency change that it can detect without averaging. For example ， a low cost TIC with a single-shot resolution of 100 ns can detect frequency changes of 1 × 10 -7 in 1 s. The current limit for TIC resolution is about 20 ps ， which means that a frequency change of 2 ×10 -11 can be detected in 1 s. Averaging over longer intervals can improve the resolution to <1 ps in some units [6].Since standard frequencies like 5 or 10 MHz are not practical to measure with a TIC ， frequency dividers or frequency mixers are used to convert the test frequency to a lower frequency. Divider systems are simpler and more versatile ， since they can be easily built or programmed to accommodate different frequencies. Mixer systems are more expensive ， require more hardware including an additional reference oscillator ， and can often measure only one input frequency (e.g.， 10 MHz) ， but they have a higher signal-to-noise ratio than divider systems.If dividers are used ， measurements are made from the TIC ， but instead of using these measurements directly ， we determine the rate of change from reading to reading. This rate of change is called the phase deviation. We can estimate frequency offset as follows ：tf=T ∆Where △t is the amount of phase deviation ， and T is the measurement period. To illustrate ， consider a measurement of +1 μs of phase deviation over a measurement period of 24 h. The unit used for measurement period (h) must be converted to the unit used for phase deviation (μs). The equation becomes11t 1us f offset ===1.1610T 86400000000us -∆⨯（），，，As shown，a device that accumulates 1 μs of phase deviation/day has a frequency offset of 1.16 × 10 -11 with respect to the reference. This simple example requires only two time interval readings to be made，and △t is simply the difference between the two readings. Often，multiple readings are taken and the frequency offset is estimated by using least squares linear regression on the data set，and obtaining △t from the slope of the least squares line. This information is usually presented as a phase plot，as shown in Fig. 17.6. The device under test is high in frequency by exactly 1×10 -9，as indicated by a phase deviation of 1 ns/s.Dimensionless frequency offset values can be converted to units of frequency (Hz) if the nominal frequency is known. To illustrate this，consider an oscillator with a nominal frequency of 5 MHz and a frequency offset of +1.16 ′10 -11. To find the frequency offset in hertz，multiply the nominal frequency by the offset：(5 ×106) (+1.16×10 -11) = 5.80×10 -5 =+0.0000580 Hz Then，add the offset to the nominal frequency to get the actual frequency：5，000，000 Hz + 0.0000580 Hz = 5，000，000.0000580 HzStabilityStability indicates how well an oscillator can produce the same time or frequency offset over a given time interval. It doesn‟t indicate whether the time or frequency is “right” or “wrong，” but only whether it stays the same. In contrast，accuracy indicates how well an oscillator has been set on time or on frequency. To understand this difference，consider that a stable oscillator that needs adjustment might produce a frequency with a large offset. Or，an unstable oscillator that was just adjusted might temporarily produce a frequency near its nominal value. Figure 17.7 shows the relationship between accuracy and stability.Stability is defined as the statistical estimate of the frequency or time fluctuations of a signal over a given time interval. These fluctuations are measured with respect to a mean frequency or time offset.Short-term stability usually refers to fluctuations over intervals less than 100 s. Long-term stability can refer to measurement intervals greater than 100 s ， but usually refers to periods longer than 1 day.Stability estimates can be made in either the frequency domain or time domain ， and can be calculated from a set of either frequency offset or time interval measurements. In some fields of measurement ， stability is estimated by taking the standard deviation of the data set. However ， standard deviation only works with stationary data ， where the results are time independent ， and the noise is white ， meaning that it is evenly distributed across the frequency band of the measurement. Oscillator data is usually no stationary ， since it contains time dependent noise contributed by the frequency offset. With stationary data ， the mean and standard deviation will converge to particular values as more measurements are made. With no stationary data ， the mean and standard deviation never converge to any particular values. Instead ， there is a moving mean that changes each time we add a measurement. For these reasons ， a non-classical statistic is often used to estimate stability in the time domain. This statistic is sometimes called the Allan variance ， but since it is the square root of the variance ， its proper name is the Allan deviation. The equation for the Allan deviation (σy (τ)) is2y i+i y -y στ1（（） where y i is a set of frequency offset measurements containing y 1， y 2， y 3， and so on ， M is the number of values in the y i series ， and the data are equally spaced in segments τ seconds long. Or2x i+1i -2x +x στi+2（（x ） Where x i is a set of phase measurements in time units containing x 1， x 2， x 3，and so on，N is the number of values in the xi series，and the data are equally spaced in segments τ seconds long. Note that while standard deviation subtracts the mean from each measurement before squaring their summation，the Allan deviation subtracts the previous data point. This differencing of successive data points removes the time dependent noise contributed by the frequency offset. An Allan deviation graph is shown in Fig. 17.8. It shows the stability of the device improving as the averaging period (τ) gets longer，since some noise types can be removed by averaging. At some point，however，more averaging no longer improves the results. This point is called the noise floor，or the point where the remaining noise consists of no stationary processes such as flicker noise or random walk. The device measured in Fig. 17.8 has a noise floor of ~5 × 10 -11at τ = 100 s.Practically speaking，a frequency stability graph also tells us how long we need to average to get rid of the noise contributed by the reference and the measurement system. The noise floor provides some indication of the amount of averaging required to obtain a TUR high enough to show us the true frequency where xi is a set of phase measurements in time units containing x1，x2，x3，and so on is the number of values in the xi series，and the data are equally s paced in segments τ seconds long. Note that while standard deviation subtracts the mean from each measurement before squaring their summation，the Allan deviation subtracts the previous data point. This differencing of successive data points removes the time dependent noise contributed by the frequency offset. An Allan deviation graph is shown in Fig. 17.8. It shows the stability of the device improving as the averaging period (τ) gets longer，since some noise types can be removed by averaging. At some point，however，more averaging no longer improves the results. This point is called the noise floor or the point where the remaining noise consists of no stationary processes such as flicker noise or random walk. The device measured in Fig. 17.8 has a noise floor of ~5 × 10 -11at τ = 100 s.Practically speaking，a frequency stability graph also tells us how long we needto average to get rid of the noise contributed by the reference and the measurement system. The noise floor provides some indication of the amount of averaging required to obtain a TUR high enough to show us the true frequency offset of the DUT. If the DUT is an atomic oscillator (section 17.4) and the reference is a radio controlled transfer standard (section 17.5) we might have to average for 24 h or longer to have confidence in the measurement result. Five noise types are commonly discussed in the time and frequency literature：white phase，flicker phase，white frequency，flicker frequency，and random walk frequency. The slope of the Allan deviation line can help identify the amount of averaging needed to remove these noise types (Fig. 17.9). The first type of noise to be removed by averaging is phase noise，or the rapid，random fluctuations in the phase of the signal. Ideally，only the device under test would contribute phase noise to the measurement，but in practice，some phase noise from the measurement system and reference needs to be removed through averaging. Note that the Allan deviation does not distinguish between white phase noise and flicker phase noise. Table 17.2 shows several other statistics used to estimate stability and identify noise types for various applications.Identifying and eliminating sources of oscillator noise can be a complex subject，but plotting the first order differences of a set of time domain measurements can provide a basic understanding of how noise is removed by averaging. Figure 17.10 was made using a segment of the data from the stability graph in Fig. 17.8. It shows phase plots dominated by white phase noise (1 s averaging) ，white frequency noise (64 s averages) ，flicker frequency noise (256 s averages)，and random walk frequency (1024 s averages). Note that the white phase noise plot has a 2 ns scale，and the other plots use a 100 ps scale.外文文献中文翻译时间和频率的基本原理介绍时间和频率标准应用于三种基本信息类型：时间，时间间隔和频率.时间信息有小时，分，秒.通常还包括日期(年，月，日).用来显示和记录时间的器件叫做钟表，如果钟表标记了一件事的发生，那么这个标记叫做时间标签或时间印记.日期和时间能确保事情的同步或同时发生.时间间隔是两个事件持续或断续的时间，时间间隔的标准单位是秒，然而许多工程上应用要求更短的时间间隔，像毫秒，微秒，纳秒，和皮秒，时间是七个基本物理量之一，并且秒是国际单位体制制定七个基本单位之一.许多区其他物理量的定义是依靠秒而定义的.秒曾经定义根据地球回转率.原子时代正式开始在1967年目前SI定义秒为：秒是铯133原子(Cs133)基态的两个超精细能级之间跃迁所对应的辐射的9，192，631，770个周期所持续的时间。
毕业设计(论文)外文资料翻译【范本模板】
南京理工大学紫金学院毕业设计（论文）外文资料翻译系：机械系专业：车辆工程专业姓名:宋磊春学号:070102234外文出处：EDU_E_CAT_VBA_FF_V5R9(用外文写)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CATIA V5 的自动化CATIA V5的自动化和脚本：在NT 和Unix上：脚本允许你用宏指令以非常简单的方式计划CATIA。
CATIA 使用在MS –VBScript中(V5.x中在NT和UNIX3。
0 )的共用部分来使得在两个平台上运行相同的宏。
在NT 平台上：自动化允许CATIA像Word/Excel或者Visual Basic程序那样与其他外用分享目标。
ATIA 能使用Word/Excel对象就像Word/Excel能使用CATIA 对象。
在Unix 平台上:CATIA将来的版本将允许从Java分享它的对象。
这将提供在Unix 和NT 之间的一个完美兼容。
CATIA V5 自动化：介绍（仅限NT）自动化允许在几个进程之间的联系:CATIA V5 在NT 上：接口COM：Visual Basic 脚本(对宏来说)，Visual Basic 为应用（适合前:Word/Excel )，Visual Basic。
COM（零部件目标模型)是“微软“标准于几个应用程序之间的共享对象。
Automation 是一种“微软“技术,它使用一种解释环境中的COM对象。
ActiveX 组成部分是“微软“标准于几个应用程序之间的共享对象,即使在解释环境里。
OLE（对象的链接与嵌入）意思是资料可以在一个其他应用OLE的资料里连结并且可以被编辑的方法(在适当的位置编辑）.在VBScript,VBA和Visual Basic之间的差别：Visual Basic(VB）是全部的版本。
它能产生独立的计划,它也能建立ActiveX 和服务器。
它可以被编辑。
VB中提供了一个补充文件名为“在线丛书“(VB的5。
软件工程专业毕业设计外文文献翻译
软件工程专业毕业设计外文文献翻译1000字本文将就软件工程专业毕业设计的外文文献进行翻译，能够为相关考生提供一定的参考。
外文文献1: Software Engineering Practices in Industry: A Case StudyAbstractThis paper reports a case study of software engineering practices in industry. The study was conducted with a large US software development company that produces software for aerospace and medical applications. The study investigated the company’s software development process, practices, and techniques that lead to the production of quality software. The software engineering practices were identified through a survey questionnaire and a series of interviews with the company’s software development managers, software engineers, and testers. The research found that the company has a well-defined software development process, which is based on the Capability Maturity Model Integration (CMMI). The company follows a set of software engineering practices that ensure quality, reliability, and maintainability of the software products. The findings of this study provide a valuable insight into the software engineering practices used in industry and can be used to guide software engineering education and practice in academia.IntroductionSoftware engineering is the discipline of designing, developing, testing, and maintaining software products. There are a number of software engineering practices that are used in industry to ensure that software products are of high quality, reliable, and maintainable. These practices include software development processes, software configuration management, software testing, requirements engineering, and project management. Software engineeringpractices have evolved over the years as a result of the growth of the software industry and the increasing demands for high-quality software products. The software industry has developed a number of software development models, such as the Capability Maturity Model Integration (CMMI), which provides a framework for software development organizations to improve their software development processes and practices.This paper reports a case study of software engineering practices in industry. The study was conducted with a large US software development company that produces software for aerospace and medical applications. The objective of the study was to identify the software engineering practices used by the company and to investigate how these practices contribute to the production of quality software.Research MethodologyThe case study was conducted with a large US software development company that produces software for aerospace and medical applications. The study was conducted over a period of six months, during which a survey questionnaire was administered to the company’s software development managers, software engineers, and testers. In addition, a series of interviews were conducted with the company’s software development managers, software engineers, and testers to gain a deeper understanding of the software engineering practices used by the company. The survey questionnaire and the interview questions were designed to investigate the software engineering practices used by the company in relation to software development processes, software configuration management, software testing, requirements engineering, and project management.FindingsThe research found that the company has a well-defined software development process, which is based on the Capability Maturity Model Integration (CMMI). The company’s software development process consists of five levels of maturity, starting with an ad hoc process (Level 1) and progressing to a fully defined and optimized process (Level 5). The company has achieved Level 3 maturity in its software development process. The company follows a set of software engineering practices that ensure quality, reliability, and maintainability of the software products. The software engineering practices used by the company include:Software Configuration Management (SCM): The company uses SCM tools to manage software code, documentation, and other artifacts. The company follows a branching and merging strategy to manage changes to the software code.Software Testing: The company has adopted a formal testing approach that includes unit testing, integration testing, system testing, and acceptance testing. The testing process is automated where possible, and the company uses a range of testing tools.Requirements Engineering: The company has a well-defined requirements engineering process, which includes requirements capture, analysis, specification, and validation. The company uses a range of tools, including use case modeling, to capture and analyze requirements.Project Management: The company has a well-defined project management process that includes project planning, scheduling, monitoring, and control. The company uses a range of tools to support project management, including project management software, which is used to track project progress.ConclusionThis paper has reported a case study of software engineering practices in industry. The study was conducted with a large US software development company that produces software for aerospace and medical applications. The study investigated the company’s software development process,practices, and techniques that lead to the production of quality software. The research found that the company has a well-defined software development process, which is based on the Capability Maturity Model Integration (CMMI). The company uses a set of software engineering practices that ensure quality, reliability, and maintainability of the software products. The findings of this study provide a valuable insight into the software engineering practices used in industry and can be used to guide software engineering education and practice in academia.外文文献2: Agile Software Development: Principles, Patterns, and PracticesAbstractAgile software development is a set of values, principles, and practices for developing software. The Agile Manifesto represents the values and principles of the agile approach. The manifesto emphasizes the importance of individuals and interactions, working software, customer collaboration, and responding to change. Agile software development practices include iterative development, test-driven development, continuous integration, and frequent releases. This paper presents an overview of agile software development, including its principles, patterns, and practices. The paper also discusses the benefits and challenges of agile software development.IntroductionAgile software development is a set of values, principles, and practices for developing software. Agile software development is based on the Agile Manifesto, which represents the values and principles of the agile approach. The manifesto emphasizes the importance of individuals and interactions, working software, customer collaboration, and responding to change. Agile software development practices include iterative development, test-driven development, continuous integration, and frequent releases.Agile Software Development PrinciplesAgile software development is based on a set of principles. These principles are:Customer satisfaction through early and continuous delivery of useful software.Welcome changing requirements, even late in development. Agile processes harness change for the customer's competitive advantage.Deliver working software frequently, with a preference for the shorter timescale.Collaboration between the business stakeholders and developers throughout the project.Build projects around motivated individuals. Give them the environment and support they need, and trust them to get the job done.The most efficient and effective method of conveying information to and within a development team is face-to-face conversation.Working software is the primary measure of progress.Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely.Continuous attention to technical excellence and good design enhances agility.Simplicity – the art of maximizing the amount of work not done – is essential.The best architectures, requirements, and designs emerge from self-organizing teams.Agile Software Development PatternsAgile software development patterns are reusable solutions to common software development problems. The following are some typical agile software development patterns:The Single Responsibility Principle (SRP)The Open/Closed Principle (OCP)The Liskov Substitution Principle (LSP)The Dependency Inversion Principle (DIP)The Interface Segregation Principle (ISP)The Model-View-Controller (MVC) PatternThe Observer PatternThe Strategy PatternThe Factory Method PatternAgile Software Development PracticesAgile software development practices are a set ofactivities and techniques used in agile software development. The following are some typical agile software development practices:Iterative DevelopmentTest-Driven Development (TDD)Continuous IntegrationRefactoringPair ProgrammingAgile Software Development Benefits and ChallengesAgile software development has many benefits, including:Increased customer satisfactionIncreased qualityIncreased productivityIncreased flexibilityIncreased visibilityReduced riskAgile software development also has some challenges, including:Requires discipline and trainingRequires an experienced teamRequires good communicationRequires a supportive management cultureConclusionAgile software development is a set of values, principles, and practices for developing software. Agile software development is based on the Agile Manifesto, which represents the values and principles of the agile approach. Agile software development practices include iterative development, test-driven development, continuous integration, and frequent releases. Agile software development has many benefits, including increased customer satisfaction, increased quality, increased productivity, increased flexibility, increased visibility, and reduced risk. Agile software development also has some challenges, including the requirement for discipline and training, the requirement for an experienced team, the requirement for good communication, and the requirement for a supportive management culture.。
土木工程-毕业设计-论文-外文翻译-中英文对照
英文原文：Concrete structure reinforcement designSheyanb oⅠWangchenji aⅡⅠFoundation Engineering Co., Ltd. Heilongjiang DongyuⅡHeilongjiang Province, East Building Foundation Engineering Co., Ltd. CoalAbstract：structure in the long-term natural environment and under the use environment's function, its function is weaken inevitably gradually, our structural engineering's duty not just must finish the building earlier period the project work, but must be able the science appraisal structure damage objective law and the degree, and adopts the effective method guarantee structure the security use, that the structure reinforcement will become an important work. What may foresee will be the 21st century, the human building also by the concrete structure, the steel structure, the bricking-up structure and so on primarily, the present stage I will think us in the structure reinforcement this aspect research should also take this as the main breakthrough direction.Key word：Concrete structure reinforcement bricking-up structure reinforcement steel structure reinforcement1 Concrete structure reinforcementConcrete structure's reinforcement divides into the direct reinforcement and reinforces two kinds indirectly, when the design may act according to the actual condition and the operation requirements choice being suitable method and the necessary technology.1.1the direct reinforcement's general method1）Enlarges the section reinforcement lawAdds the concretes cast-in-place level in the reinforced concrete member in bending compression zone, may increase the section effective height, the expansion cross sectional area, thus enhances the component right section anti-curved, the oblique section anti-cuts ability and the section rigidity, plays the reinforcement reinforcement the role.In the suitable muscle scope, the concretes change curved the component right section supporting capacity increase along with the area of reinforcement and the intensity enhance. In the original component right section ratio of reinforcement not too high situation, increases the main reinforcement area to be possible to propose the plateau component right section anti-curved supporting capacity effectively. Is pulled in the section the area to add the cast-in-place concrete jacket to increase the component section, through new Canada partial and original component joint work, but enhances the component supporting capacity effectively, improvement normal operational performance.Enlarges the section reinforcement law construction craft simply, compatible, and has the mature design and the construction experience; Is suitable in Liang, the board, the column, the wall and the general structure concretes reinforcement; But scene construction's wet operating time is long, to produces has certain influence with the life, and after reinforcing the building clearance has certain reduction.2) Replacement concretes reinforcement lawThis law's merit with enlarges the method of sections to be close, and after reinforcing, does not affect building's clearance, but similar existence construction wet operating time long shortcoming; Is suitable somewhat low or has concretes carrier's and so on serious defect Liang, column in the compression zone concretes intensity reinforcement.3) the caking outsourcing section reinforcement lawOutside the Baotou Steel Factory reinforcement is wraps in the section or the steel plate is reinforced component's outside, outside the Baotou Steel Factory reinforces reinforced concrete Liang to use the wet outsourcing law generally, namely uses the epoxy resinification to be in the milk and so on methods with to reinforce the section the construction commission to cake a whole, after the reinforcement component, because is pulled with the compressed steel cross sectional area large scale enhancement, therefore right section supporting capacity and section rigidity large scale enhancement.This law also said that the wet outside Baotou Steel Factory reinforcement law, the stress is reliable, the construction is simple, the scene work load is small, but is big with the steel quantity, and uses in above not suitably 600C in the non-protection's situation the high temperature place; Is suitable does not allow in the use obviously to increase the original component section size, but requests to sharpen its bearing capacity large scale the concrete structure reinforcement.4) Sticks the steel reinforcement lawOutside the reinforced concrete member in bending sticks the steel reinforcement is (right section is pulled in the component supporting capacity insufficient sector area, right section compression zone or oblique section) the superficial glue steel plate, like this may enhance is reinforced component's supporting capacity, and constructs conveniently.This law construction is fast, the scene not wet work or only has the plastering and so on few wet works, to produces is small with the life influence, and after reinforcing, is not remarkable to the original structure outward appearance and the original clearance affects, but the reinforcement effect is decided to a great extent by the gummy craft and the operational level; Is suitable in the withstanding static function, and is in the normal humidity environment to bend or the tension member reinforcement.5) Glue fibre reinforcement plastic reinforcement lawOutside pastes the textile fiber reinforcement is pastes with the cementing material the fibre reinforcement compound materials in is reinforced the component to pull the region, causes it with to reinforce the section joint work, achieves sharpens the component bearing capacity the goal. Besides has glues the steel plate similar merit, but also has anticorrosive muddy, bears moistly, does not increase the self-weight of structure nearly, durably, the maintenance cost low status merit, but needs special fire protection processing, is suitable in each kind of stress nature concrete structure component and the general construction.This law's good and bad points with enlarge the method of sections to be close; Is suitable reinforcement which is insufficient in the concrete structure component oblique section supporting capacity, or must exert the crosswise binding force to the compressional member the situation.6) Reeling lawThis law's good and bad points with enlarge the method of sections to be close; Is suitable reinforcement which is insufficient in the concrete structure component oblique section supporting capacity, or must exert the crosswise binding force to the compressional member the situation.7) Fang bolt anchor lawThis law is suitable in the concretes intensity rank is the C20~C60 concretes load-bearing member transformation, the reinforcement; It is not suitable for already the above structure which and the light quality structure makes decent seriously. 1.2The indirect reinforcement's general method1)Pre-stressed reinforcement law(1)Thepre-stressed horizontal tension bar reinforces concretes member in bending,because the pre-stressed and increases the exterior load the combined action, in the tension bar has the axial tension, this strength eccentric transmits on the component through the pole end anchor (, when tension bar and Liang board bottom surface close fitting, tension bar can look for tune together with component, this fashion has partial pressures to transmit directly for component bottom surface), has the eccentric compression function in the component, this function has overcome the bending moment which outside the part the load produces, reduced outside the load effect, thus sharpened component's anti-curved ability. At the same time, because the tension bar passes to component's pressure function, the component crack development can alleviate, the control, the oblique section anti-to cut the supporting capacity also along with it enhancement.As a result of the horizontal lifting stem's function, the original component's section stress characteristic by received bends turned the eccentric compression, therefore, after the reinforcement, component's supporting capacity was mainly decided in bends under the condition the original component's supporting capacity 。
毕业设计_外文文献翻译
毕业设计_外文文献翻译本科毕业设计外文文献翻译（题目：packethandlinghardwaresupport学生姓名：学院：系别：专业：班级：指导教师：二〇一四年六月packethandlinghardwaresupport参考文献：texasinstruments1101low-powersub-1ghzrftransceiver.ti.2013 the1101hasbuilt-inhardwaresupportforpacketorientedradioprotocols.intransmitmode,thepackethandlercanbeconfiguredtoaddth efollowingelementstothepacketstoredinthetxfifo:aprogrammablenumberofpreamblebytesatwobytesynchronization(sync)word.canbeduplicatedtogivea4-b ytesyncword(remended).itisnotpossibletoonlyinsertpreambleoronl yinsertasyncwordacrcchecksumputedoverthedatafield.theremendedsettingis4-bytepreambleand4-bytesyncword,exceptf or500kbauddataratewheretheremendedpreamblelengthis8bytes.in addition,thefollowingcanbeimplementedonthedatafieldandtheop tional2-bytecrcchecksum:whiteningofthedatawithapn9sequenceforwarderrorcorrection(fec)bytheuseofinterleavingandcodingo fthedata(convolutionalcoding)inreceivemode,thepackethandlingsupportwillde-constructtheda tapacketbyimplementingthefollowing(ifenabled):preambledetectionsyncworddetectioncrcputationandcrccheckonebyteaddresscheckpacketlengthcheck(lengthbytecheckedagainstaprogrammablemaxi mumlength)de-whiteningde-interleavinganddecodingoptionally,twostatusbytes(seetable27andtable28)withrssivalu e,linkqualityindication,andcrcstatuscanbeappendedintherxfif o.1.datawhiteningfromaradioperspective,theidealovertheairdataarerandomanddcf ree.thisresultsinthesmoothestpowerdistributionovertheoupied bandwidth.thisalsogivestheregulationloopsinthereceiverunifo rmoperationconditions(ondatadependencies).realdataoftencontainlongsequencesofzerosandones.inthesecase s,performancecanbeimprovedbywhiteningthedatabeforetransmitting,andde-whiteningthedatainthereceiver.with1101,thiscanbedoneautomatically.bysettingpktctrlo.white _data=1,alldata,exceptthepreambleandthesyncwordwillbexor-ed witha9-bitpseudo-random(pn9)sequencebeforebeingtransmitted. thisisshowninfigure16.atthereceiverend,thedataarexor-edwith thesamepseudorandomsequence.inthisway,thewhiteningisreverse d,andtheoriginaldataappearinthereceiver.thepn9sequenceisini tializedtoall1’s.2.packetformattheformatofthedatapacketcanbeconfiguredandconsistsofthefoll owingitems(seefigure17):preamblesynchronizationwordoptionallengthbyteoptionaladdressbytepayloadoptional2bytecrcthepreamblepatternisanalternatingsequenceof onesandzeros(10101010…).theminimumlengthofthepreambleispro grammablethroughthevalueofmdmcfg1.num_preamble.whenenabling tx,themodulatorwillstarttransmittingthepreamble.whentheprog rammednumberofpreamblebyteshasbeentransmitted,themodulatorwillsendthesyncwordandthendatafromt hetxfifoifdataisavailable.ifthetxfifoisempty,themodulatorwi llcontinuerosendpreamblebytesuntilthefirstbyteiswrittentoth etxfifo.themodulatorwillthensendthesyncwordandthenthedataby tes.thesynchronizationwordisatwo-bytevaluesetinthesync1andsync0 registers.thesyncwordprovidesbytesynchronizationoftheiningp acket.aone-bytesyncwordcanbeemulatedbysettingtheaync1valuet othepreamblepattern.itisalsopossibletoemulatea32bitsyncword bysettingmdmcfg2.sync_modeto3or7.thesyncwordwillthenberepea tedtwice.1101supportsbothconstantpacketlengthprotocolsandvariablelen gthprotocols.variableorfixedpacketlengthmodecanbeusedforpac ketsupto255bytes.forlongerpackets,infinitepacketlengthmodem ustbeused.fixedpacketlengthmodeisselectedbysettingpktctrl0.length_con fig=0.thedesiredpacketlengthissetbythepktlenregister.thisvaluemustbedifferentfrom0.invariablepacketlengthmode,pktctrl0.length_config=1,thepack etlengthisconfiguredbythefirstbyteafterthesyncword.thepacke tlengthisdefinedasthepayloaddata,excludingthelengthbyteando ptionalcrc.thepktlenregisterisusedtosetthemaximumpacketleng thallowedinrx.anypacketreceivedwithalengthbytewithavaluegre aterthanpktlenwillbediscarded.thepktlenvaluemustbedifferent from0.thebytewrittentothetxfifomustbedifferentfrom0.withpktctrl0.length_config=2,thepacketlengthissettoinfinite andtransmissionandreceptionwillcontinueuntilturnedoffmanual ly.asdescribedinthenextsection,thiscanbeusedtosupportpacket formatswithdifferentlengthconfigurationthannativelysupporte dby1101.oneshouldmakesurethattxisnotturnoffduringthetransmissionofthefirsthalfofanybyte.refertothe11012.1arbitrarylengthfieldconfigurationthepacketlengthregister,pktlen,canbereprogrammedduringrecei veandtransmit.inbinationwithfixedpacketlengthmode(pktctrl0. length_config=0),thisopensthepossibilitytohaveadifferentlen gthfieldconfigurationcansupportedforvariablelengthpackets(i nvariablepacketlengthmodethelengthbyteisthefirstbyteafterth esyncword).atthestartofreception,thepacketlengthissetalarge value.themcureadsoutenoughbytestointerpretthelengthfieldint hepacket.thenthepktlenvalueissetaordingtothisvalue.theendof packetwillourwhenthebytecounterinthepackethandlerisequaltot hepktlenregister.thus,themcumustbeabletoprogramthecorrectle ngth,beforetheinternalcounterreachesthepacketlength.2.2packetlength>255thepacketautomationcontrolregister,pktctrl0,canbereprogramm edduringtxandrx.thisopensthepossibilitytotransmitandreceive packetsthatarelongerthan256bytesandstillbeabletousethepacke thandlinghardwaresupport.atthestartofthepacket,theinfinitep acketlengthmode(pktctrl0.length_config=2)mustbeactive.onthe txside,thepktlenregisterissettomod(length,256).ontherxsidet hemcureadsoutenoughbytestointerpretthelengthfieldinthepacke tandsetsthepktlenregistertomod(length,256).whenlessthan256b ytesremainsofthepacket,themcudisablesinfinitepacketlengthmo deandactivatesfixedpacketlengthmode.whentheinternalbytecoun terreachesthepktlenvalue,thetransmissionorreceptionends(the radioentersthestatedeterminedbytxoff_modeorrxoff_mode).auto maticcrcappending/checkingcanalsobeused(bysettingpktctrl0.c rc_en=1).whenforexamplea600-bytepacketistobetransmitted,themcushould dothefollowing(seealsofigure18)setpktctrl0.length_config=2.pre-programthepktlenregistertomod(600,256)=88.transmitatleast345bytes(600-255),forexamplebyfillingthe64-b ytetxfifosixtimes(384bytestransmitted).setpktctrl0.length_config=0.thetransmissionendswhenthepacketcounterreaches88.atotalof60 0bytesaretransmitted.3packetfilteringinreceivemode1101supportsthreedifferenttypesofpacket-filtering;addressfi ltering,maximumlengthfiltering,andcrcfiltering.3.1addressingfilteringsettingpktctrl1.adr_chktoanyothervaluethanzeroenablesthepac ketaddressfilter.thepackethandlerenginewillparethedestinati onaddressbyteinthepacketwiththeprogrammednodeaddressinthead drregisterandthe0*00broadcastaddresswhenpktctrl1.adr_chk=10 orboththe0*00and0*ffbroadcastaddresseswhenpktctrl1.adr_chk= 11.ifthereceivedaddressmatchesavalidaddress,thepacketisrece ivedandwrittenintotherxfifo.iftheaddressmatchfails,thepacke tisdiscardedandreceivemoderestarted(regardlessofthemcsm1.rx off_modesetting).ifthereceivedaddressmatchesavalidaddresswhenusinginfinitepacketlengthmodeandaddressfilteringisenabled,0*ffwillbewritte nintotherxfifofollowedbytheaddressbyteandthenthepayloaddata.3.2maximumlengthfilteringinvariablepacketlengthmode,pktctrl0.length_config=1,thepktl en.packet_lengthregistervalueisusedtosetthemaximumallowedpa cketlength.ifthereceivedlengthbytehasalargervaluethanthis,t hepacketisdiscardedandreceivemoderestarted(regardlessofthem csm1.rxoff_modesetting).3.3crcfilteringthefilteringofapacketwhencrccheckfailsisenabledbysettingpkt ctrl1.crc_autoflush=1.thecrcautoflushfunctionwillflushtheen tirerxfifoifthecrccheckfails.afterautoflushingtherxfifo,the nextstatedependsonthemcsm1.rxoff_modesetting.whenusingtheautoflushfunction,themaximumpacketlengthis63byt esinvariablepacketlengthmode.notethatwhenpktctrl1append_sta tusisenabled,themaximumallowedpacketlengthisreducedbytwobyt esinordertomakeroomintherxfifoforthetwostatusbytesappendeda ttheendofthepacket.sincetheentirerxfifoisflushedwhenthecrcc heckfails,thepreviouslyreceivedpacketmustbereadoutofthefifo beforereceivingthecurrentpacket.themcumustnotreadfromthecur rentpacketuntilthecrchasbeencheckedasok.4packethandlingintr ansmitmodethepayloadthatistobetransmittedmustbewrittenintothetxfifo.t hefirstbytewrittenmustbethelengthbytewhenvariablepacketleng thisenabled.thelengthbytehasavalueequaltothepayloadofthepac ket(includingtheoptionaladdressbyte).ifaddressrecognitionisenabledonthereceiver,thesecondbytewrittentothetxfifomustbet headdressbyte.iffixedpacketlengthisenabled,thefirstbytewrittentothetxfifo shouldbetheaddress(assumingthereceiverusesaddressrecognitio n).themodulatorwillfirstsendtheprogrammednumberofpreamblebytes .ifdataisavaibleinthetxfifo,themodulatorwillsendthetwo-byte s(optionally4-byte)syncwordfollowedbythepayloadinthetxfifo.ifcrcisenabled,thec hecksumiscalculatedoverallthedatapulledfromthetxfifo,andthe resultissentastwoextrabytesfollowingthepayloaddata.ifthetxf iforunsemptybeforethepletepackethasbeentransmitted,theradiowillentertxfifo_underflowstate.theonlywaytoexitthisstateisb yissuingansftxstrobe.writingtothetxfifoafterithasbeenunderf lowedwillnotrestarttxmode.ifwhiteningisenabled,everythingfollowingthesyncwordswillbew hitened.thisisdonebeforetheoptionalfec/interleaverstage.whi teningisenabledbysettingpktctrl0.white_data=1.iffec/interleavingisenabled,everythingfollowingthesyncwords willbescrambledbytheinterleaverandfecencodedbeforebeingmodu lated.fecisenabledbysettingmdmcfg1.fec_en=1.5packethandlinginreceivemodeinreceivemode,thedemodulatorandpackethandlerwillsearchforav alidpreambleandthesyncword.whenfound,thesynchronismandwillreceivethefirstpayloadbyte.iffec/interleavingisenabled,thefecdecoderwillstarttodecodet hefirstpayloadbyte.theintrerleaverwillde-scramblethebitsbef oreanyotherprocessingisdonetothedata.ifwhiteningisenabled,thedatawillbede-whitenedatthisstage.whenvariablepacketlengthmodeisenabled,thefirstbyteistheleng thbyte.thepackethandlerstoresthisvalueasthepacketlengthandr eceivesthenumberofbytesindicatedbythelengthbyte.iffixedpack etlengthmodeisused,thepackethandlerwillaepttheprogrammednum berofbytes.next,thepackethandleroptionallycheckstheaddressandonlycontinuesthereceptioniftheaddressmatches.ifautomaticcrccheckisen abled,thepackethandlerputescrcandmatchesitwiththeappendedcr cchecksum.attheendofthepayload,thepackethandlerwilloptionallywhitetwo extrapacketstatusbytes(seetable27andtable28)thatcontaincrcs tatus,linkqualityindication,andrssivalue.6packethandlinginfirmwarewhenimplementingapacketorientedradioprotocolinfirmware,them cuneedstoknowwhenapackethasbeenreceived/transmitted.additio nally,forpacketslongerthan64bytes,therxfifoneedstoberefille dwhiteintx.thismeansthatthemcuneedstoknowthenumberofbytesth atcanbereadfromorwrittentotherxfifoandtxfiforespectively.th erearetwopossiblesolutionstogetthenecessarystatusinformation:a)interruptdrivensolutionthegdopinscanbeusedinbothrxandtxtogiveaninterruptwhenasyncw ordhasbeenreceived/transmittedorwhenapletepackethasbeenrece ived/transmittedbysettingiofgx.gdox_cfg=0*06.inaddition,the rearetwoconfigurationsfortheiocfgx.gdox_cfgregisterthatcanb eusedasaninterruptsourcetoprovideinformationonhowmanybytest hatareintherxfifoandtxfiforespectively.theiocfgx.gdox_cfg=0 *02andiocfgx.gdox_cfg=0*03configurationsareassociatedwithth etxfifo.seetable41formoreinformation.b)spipollingthepktststusregistercanbepolledatagivenratetogetinformation aboutthecurrentgdo2andgdo0valuesrespectively.therxbytesandtxbytesregisterscanbepolledatagivenratetogetinformationabout thenumberofbytesintherxfifoandtxfiforespectively.alternativ ely,thenumberofbytesintherxfifoandthetxfifocanbereadfromthe chipstatusbytereturnedonthemisolineeachtimeaheaderbyte,data byte,ormandstrobeissentonthespibus.itisremendedtoemployaninterruptdrivensolutionsincehighrates pipollingreducestherxsensitivity.furthermore,asexplainedins ection10.3andthe1101erratanotes[4],whenusingspipolling,ther eisasmall,butfinite,probabilitythatasinglereadfromregisters pkstatus,rxbytesandtxbytesisbeingcorrupt.thesameisthecasewh enreadingthechipstatusbyte.refertothetiwebsiteforswexamples([9]and[10]).数据包处理的硬件支持1101提供了对数据包导向无线协议的内置硬件支持。
本科毕业设计(论文)外文翻译译文
本科毕业设计（论文）外文翻译译文学生姓名：院（系）：油气资源学院专业班级：物探0502指导教师：完成日期：年月日地震驱动评价与发展：以玻利维亚冲积盆地的研究为例起止页码：1099——1108出版日期：NOVEMBER 2005THE LEADING EDGE出版单位：PanYAmericanYEnergyvBuenosYAiresvYArgentinaJPYBLANGYvYBPYExplorationvYHoustonvYUSAJ.C.YCORDOVAandYE.YMARTINEZvYChacoYS.A.vYSantaYCruzvYBolivia 通过整合多种地球物理地质技术，在玻利维亚冲积盆地，我们可以减少许多与白垩纪储集层勘探有关的地质技术风险。
通过对这些远景区进行成功钻探我们可以验证我们的解释。
这些方法包括盆地模拟，联井及地震叠前同时反演，岩石性质及地震属性解释，A VO/A V A,水平地震同相轴，光谱分解。
联合解释能够得到构造和沉积模式的微笑校正。
迄今为止，在新区有七口井已经进行了成功钻探。
基质和区域地质。
Tarija/Chaco盆地的subandean 褶皱和冲断带山麓的中部和南部，部分扩展到玻利维亚的Boomerange地区经历了集中的成功的开采。
许多深大的泥盆纪气田已经被发现，目前正在生产。
另外在山麓发现的规模较小较浅的天然气和凝析气田和大的油田进行价格竞争，如果他们能产出较快的油流而且成本低。
最近发现气田就是这种情况。
接下来，我们赋予Aguja的虚假名字就是为了讲述这些油田的成功例子。
图1 Aguja油田位于玻利维亚中部Chaco盆地的西北角。
基底构造图显示了Isarzama背斜的相对位置。
地层柱状图显示了主要的储集层和源岩。
该油田在Trija和冲积盆地附近的益背斜基底上，该背斜将油田和Ben i盆地分开（图1），圈闭类型是上盘背斜，它存在于连续冲断层上，Aguja有两个主要结构：Aguja中部和Aguja Norte,通过重要的转换压缩断层将较早开发的“Sur”油田分开Yantata Centro结构是一个三路闭合对低角度逆冲断层并伴随有小的摆幅。
外文翻译范本
西安科技大学高新学院本科毕业设计本科毕业设计（（论文论文））外文翻译译文外文翻译译文学生姓名学生姓名学生姓名 : 熊 静 院院 （系）: 建筑与土木工程 专业班级专业班级专业班级 : 工程管理0703 指导教师指导教师指导教师 : 胥卫平 完成日期完成日期完成日期 : 2010年10月10日求要 求1、外文翻译是毕业设计（论文）的主要内容之一，必须学生独立完成。
2、外文翻译译文内容应与学生的专业或毕业设计（论文）内容相关，不得少于15000印刷符号。
3.外文翻译译文用A4纸打印。
文章标题用3号宋体，章节标题用4号宋体，正文用小4号宋体，20磅行距；页边距上、下、左、右均为2.5cm，左侧装订，装订线0.5cm。
按中文翻译在上，外文原文在下的顺序装订。
4、年月日等的填写，用阿拉伯数字书写，要符合《关于出版物上数字用法的试行规定》，如“2005年2月26日”。
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房 地 产 市 场 的 泡 沫 理查德赫林 苏珊沃特泽尔/ Lurie房地产中心工作文件＃402理查德赫林沃顿商学院宾夕法尼亚大学宾夕法尼亚州费城，19104 herring@苏珊沃特沃顿商学院宾夕法尼亚大学宾夕法尼亚州费城，19104wachter@ 2002年3月2002年4月22-24日，在芝加哥编写了与世界银行，芝加哥联邦储备银行集团的会议“资产价格泡沫：货币的含义，法规，政策和国际政策。
/newsletter/bubbles.pdf房地产市场的泡沫理查德赫林、苏珊沃特简介房地产泡沫可能会出现没有银行危机。
和银行业危机可能没有出现房地产泡沫。
但是，这两种现象都在显着的相关实例数据。
实体经济的后果，对银行的依赖作用在该国的金融体系。
在美国，银行只持有约22％的总资产，大多数借款人可以找到替代品的银行贷款和一般的影响经济活动水平相对轻微。
但是，在一些国家，银行扮演更主导作用，如美国的大萧条之前，大（其中银行持有65％的总资产），或现今日（其中79％的资产银行持有的总数），或新兴 市场（如银行往往持有超过80％的资产总额），为的后果实体经济可以更加严峻。
毕业设计英文 翻译(原文)
编号：毕业设计(论文)外文翻译（原文）院（系）：桂林电子科技大学专业：电子信息工程学生姓名： xx学号： xxxxxxxxxxxxx 指导教师单位：桂林电子科技大学姓名： xxxx职称： xx2014年x月xx日Timing on and off power supplyusesThe switching power supply products are widely used in industrial automation and control, military equipment, scientific equipment, LED lighting, industrial equipment,communications equipment,electrical equipment,instrumentation, medical equipment, semiconductor cooling and heating, air purifiers, electronic refrigerator, LCD monitor, LED lighting, communications equipment, audio-visual products, security, computer chassis, digital products and equipment and other fields.IntroductionWith the rapid development of power electronics technology, power electronics equipment and people's work, the relationship of life become increasingly close, and electronic equipment without reliable power, into the 1980s, computer power and the full realization of the switching power supply, the first to complete the computer Power new generation to enter the switching power supply in the 1990s have entered into a variety of electronic, electrical devices, program-controlled switchboards, communications, electronic testing equipment power control equipment, power supply, etc. have been widely used in switching power supply, but also to promote the rapid development of the switching power supply technology .Switching power supply is the use of modern power electronics technology to control the ratio of the switching transistor to turn on and off to maintain a stable output voltage power supply, switching power supply is generally controlled by pulse width modulation (PWM) ICs and switching devices (MOSFET, BJT) composition. Switching power supply and linear power compared to both the cost and growth with the increase of output power, but the two different growth rates. A power point, linear power supply costs, but higher than the switching power supply. With the development of power electronics technology and innovation, making the switching power supply technology to continue to innovate, the turning points of this cost is increasingly move to the low output power side, the switching power supply provides a broad space for development.The direction of its development is the high-frequency switching power supply, high frequency switching power supply miniaturization, and switching power supply into a wider range of application areas, especially in high-tech fields, and promote the miniaturization of high-tech products, light of. In addition, the development and application of the switching power supply in terms of energy conservation, resource conservation and environmental protection are of great significance.classificationModern switching power supply, there are two: one is the DC switching power supply; the other is the AC switching power supply. Introduces only DC switching power supply and its function is poor power quality of the original eco-power (coarse) - such as mains power or battery power, converted to meet the equipment requirements of high-quality DC voltage (Varitronix) . The core of the DC switching power supply DC / DC converter. DC switching power supply classification is dependent on the classification of DC / DC converter. In other words, the classification of the classification of the DC switching power supply and DC/DC converter is the classification of essentially the same, the DC / DC converter is basically a classification of the DC switching power supply.DC /DC converter between the input and output electrical isolation can be divided into two categories: one is isolated called isolated DC/DC converter; the other is not isolated as non-isolated DC / DC converter.Isolated DC / DC converter can also be classified by the number of active power devices. The single tube of DC / DC converter Forward (Forward), Feedback (Feedback) two. The double-barreled double-barreled DC/ DC converter Forward (Double Transistor Forward Converter), twin-tube feedback (Double Transistor Feedback Converter), Push-Pull (Push the Pull Converter) and half-bridge (Half-Bridge Converter) four. Four DC / DC converter is the full-bridge DC / DC converter (Full-Bridge Converter).Non-isolated DC / DC converter, according to the number of active power devices can be divided into single-tube, double pipe, and four three categories. Single tube to a total of six of the DC / DC converter, step-down (Buck) DC / DC converter, step-up (Boost) DC / DC converters, DC / DC converter, boost buck (Buck Boost) device of Cuk the DC / DC converter, the Zeta DC / DC converter and SEPIC, the DC / DC converter. DC / DC converters, the Buck and Boost type DC / DC converter is the basic buck-boost of Cuk, Zeta, SEPIC, type DC / DC converter is derived from a single tube in this six. The twin-tube cascaded double-barreled boost (buck-boost) DC / DC converter DC / DC converter. Four DC / DC converter is used, the full-bridge DC / DC converter (Full-Bridge Converter).Isolated DC / DC converter input and output electrical isolation is usually transformer to achieve the function of the transformer has a transformer, so conducive to the expansion of the converter output range of applications, but also easy to achieve different voltage output , or a variety of the same voltage output.Power switch voltage and current rating, the converter's output power is usually proportional to the number of switch. The more the number of switch, the greater the output power of the DC / DC converter, four type than the two output power is twice as large,single-tube output power of only four 1/4.A combination of non-isolated converters and isolated converters can be a single converter does not have their own characteristics. Energy transmission points, one-way transmission and two-way transmission of two DC / DC converter. DC / DC converter with bi-directional transmission function, either side of the transmission power from the power of lateral load power from the load-lateral side of the transmission power.DC / DC converter can be divided into self-excited and separately controlled. With the positive feedback signal converter to switch to self-sustaining periodic switching converter, called self-excited converter, such as the the Luo Yeer (Royer,) converter is a typical push-pull self-oscillating converter. Controlled DC / DC converter switching device control signal is generated by specialized external control circuit.the switching power supply.People in the field of switching power supply technology side of the development of power electronic devices, while the development of the switching inverter technology, the two promote each other to promote the switching power supply annual growth rate of more than two digits toward the light, small, thin, low-noise, high reliability, the direction of development of anti-jamming. Switching power supply can be divided into AC / DC and DC / DC two categories, AC / AC DC / AC, such as inverters, DC / DC converter is now modular design technology and production processes at home and abroad have already matured and standardization, and has been recognized by the user, but AC / DC modular, its own characteristics make the modular process, encounter more complex technology and manufacturing process. Hereinafter to illustrate the structure and characteristics of the two types of switching power supply.Self-excited: no external signal source can be self-oscillation, completely self-excited to see it as feedback oscillation circuit of a transformer.Separate excitation: entirely dependent on external sustain oscillations, excited used widely in practical applications. According to the excitation signal structure classification; can be divided into pulse-width-modulated and pulse amplitude modulated two pulse width modulated control the width of the signal is frequency, pulse amplitude modulation control signal amplitude between the same effect are the oscillation frequency to maintain within a certain range to achieve the effect of voltage stability. The winding of the transformer can generally be divided into three types, one group is involved in the oscillation of the primary winding, a group of sustained oscillations in the feedback winding, there is a group of load winding. Such as Shanghai is used in household appliances art technological production of switching power supply, 220V AC bridge rectifier, changing to about 300V DC filter added tothe collector of the switch into the transformer for high frequency oscillation, the feedback winding feedback to the base to maintain the circuit oscillating load winding induction signal, the DC voltage by the rectifier, filter, regulator to provide power to the load. Load winding to provide power at the same time, take up the ability to voltage stability, the principle is the voltage output circuit connected to a voltage sampling device to monitor the output voltage changes, and timely feedback to the oscillator circuit to adjust the oscillation frequency, so as to achieve stable voltage purposes, in order to avoid the interference of the circuit, the feedback voltage back to the oscillator circuit with optocoupler isolation.technology developmentsThe high-frequency switching power supply is the direction of its development, high-frequency switching power supply miniaturization, and switching power supply into the broader field of application, especially in high-tech fields, and promote the development and advancement of the switching power supply, an annual more than two-digit growth rate toward the light, small, thin, low noise, high reliability, the direction of the anti-jamming. Switching power supply can be divided into AC / DC and DC / DC two categories, the DC / DC converter is now modular design technology and production processes at home and abroad have already matured and standardized, and has been recognized by the user, but modular AC / DC, because of its own characteristics makes the modular process, encounter more complex technology and manufacturing process. In addition, the development and application of the switching power supply in terms of energy conservation, resource conservation and environmental protection are of great significance.The switching power supply applications in power electronic devices as diodes, IGBT and MOSFET.SCR switching power supply input rectifier circuit and soft start circuit, a small amount of applications, the GTR drive difficult, low switching frequency, gradually replace the IGBT and MOSFET.Direction of development of the switching power supply is a high-frequency, high reliability, low power, low noise, jamming and modular. Small, thin, and the key technology is the high frequency switching power supply light, so foreign major switching power supply manufacturers have committed to synchronize the development of new intelligent components, in particular, is to improve the secondary rectifier loss, and the power of iron Oxygen materials to increase scientific and technological innovation in order to improve the magnetic properties of high frequency and large magnetic flux density (Bs), and capacitor miniaturization is a key technology. SMT technology allows the switching power supply has made considerable progress, the arrangement of the components in the circuit board on bothsides, to ensure that the light of the switching power supply, a small, thin. High-frequency switching power supply is bound to the traditional PWM switching technology innovation, realization of ZVS, ZCS soft-switching technology has become the mainstream technology of the switching power supply, and a substantial increase in the efficiency of the switching power supply. Indicators for high reliability, switching power supply manufacturers in the United States by reducing the operating current, reducing the junction temperature and other measures to reduce the stress of the device, greatly improve the reliability of products.Modularity is the overall trend of switching power supply, distributed power systems can be composed of modular power supply, can be designed to N +1 redundant power system, and the parallel capacity expansion. For this shortcoming of the switching power supply running noise, separate the pursuit of high frequency noise will also increase, while the use of part of the resonant converter circuit technology to achieve high frequency, in theory, but also reduce noise, but some The practical application of the resonant converter technology, there are still technical problems, it is still a lot of work in this field, so that the technology to be practical.Power electronics technology innovation, switching power supply industry has broad prospects for development. To accelerate the pace of development of the switching power supply industry in China, it must take the road of technological innovation, out of joint production and research development path with Chinese characteristics and contribute to the rapid development of China's national economy.Developments and trends of the switching power supply1955 U.S. Royer (Roger) invented the self-oscillating push-pull transistor single-transformer DC-DC converter is the beginning of the high-frequency conversion control circuit 1957 check race Jen, Sen, invented a self-oscillating push-pull dual transformers, 1964, U.S. scientists canceled frequency transformer in series the idea of switching power supply, the power supply to the size and weight of the decline in a fundamental way. 1969 increased due to the pressure of the high-power silicon transistor, diode reverse recovery time shortened and other components to improve, and finally made a 25-kHz switching power supply.At present, the switching power supply to the small, lightweight and high efficiency characteristics are widely used in a variety of computer-oriented terminal equipment, communications equipment, etc. Almost all electronic equipment is indispensable for a rapid development of today's electronic information industry power mode. Bipolar transistor made of 100kHz, 500kHz power MOS-FET made, though already the practical switching power supply is currently available on the market, but its frequency to be further improved. Toimprove the switching frequency, it is necessary to reduce the switching losses, and to reduce the switching losses, the need for high-speed switch components. However, the switching speed will be affected by the distribution of the charge stored in the inductance and capacitance, or diode circuit to produce a surge or noise. This will not only affect the surrounding electronic equipment, but also greatly reduce the reliability of the power supply itself. Which, in order to prevent the switching Kai - closed the voltage surge, RC or LC buffers can be used, and the current surge can be caused by the diode stored charge of amorphous and other core made of magnetic buffer . However, the high frequency more than 1MHz, the resonant circuit to make the switch on the voltage or current through the switch was a sine wave, which can reduce switching losses, but also to control the occurrence of surges. This switch is called the resonant switch. Of this switching power supply is active, you can, in theory, because in this way do not need to greatly improve the switching speed of the switching losses reduced to zero, and the noise is expected to become one of the high-frequency switching power supply The main ways. At present, many countries in the world are committed to several trillion Hz converter utility.the principle of IntroductionThe switching power supply of the process is quite easy to understand, linear power supplies, power transistors operating in the linear mode and linear power, the PWM switching power supply to the power transistor turns on and off state, in both states, on the power transistor V - security product is very small (conduction, low voltage, large current; shutdown, voltage, current) V oltammetric product / power device is power semiconductor devices on the loss.Compared with the linear power supply, the PWM switching power supply more efficient process is achieved by "chopping", that is cut into the amplitude of the input DC voltage equal to the input voltage amplitude of the pulse voltage. The pulse duty cycle is adjusted by the switching power supply controller. Once the input voltage is cut into the AC square wave, its amplitude through the transformer to raise or lower. Number of groups of output voltage can be increased by increasing the number of primary and secondary windings of the transformer. After the last AC waveform after the rectifier filter the DC output voltage.The main purpose of the controller is to maintain the stability of the output voltage, the course of their work is very similar to the linear form of the controller. That is the function blocks of the controller, the voltage reference and error amplifier can be designed the same as the linear regulator. Their difference lies in the error amplifier output (error voltage) in the drive before the power tube to go through a voltage / pulse-width conversion unit.Switching power supply There are two main ways of working: Forward transformand boost transformation. Although they are all part of the layout difference is small, but the course of their work vary greatly, have advantages in specific applications.the circuit schematicThe so-called switching power supply, as the name implies, is a door, a door power through a closed power to stop by, then what is the door, the switching power supply using SCR, some switch, these two component performance is similar, are relying on the base switch control pole (SCR), coupled with the pulse signal to complete the on and off, the pulse signal is half attentive to control the pole voltage increases, the switch or transistor conduction, the filter output voltage of 300V, 220V rectifier conduction, transmitted through the switching transformer secondary through the transformer to the voltage increase or decrease for each circuit work. Oscillation pulse of negative semi-attentive to the power regulator, base, or SCR control voltage lower than the original set voltage power regulator cut-off, 300V power is off, switch the transformer secondary no voltage, then each circuit The required operating voltage, depends on this secondary road rectifier filter capacitor discharge to maintain. Repeat the process until the next pulse cycle is a half weeks when the signal arrival. This switch transformer is called the high-frequency transformer, because the operating frequency is higher than the 50HZ low frequency. Then promote the pulse of the switch or SCR, which requires the oscillator circuit, we know, the transistor has a characteristic, is the base-emitter voltage is 0.65-0.7V is the zoom state, 0.7V These are the saturated hydraulic conductivity state-0.1V-0.3V in the oscillatory state, then the operating point after a good tune, to rely on the deep negative feedback to generate a negative pressure, so that the oscillating tube onset, the frequency of the oscillating tube capacitor charging and discharging of the length of time from the base to determine the oscillation frequency of the output pulse amplitude, and vice versa on the small, which determines the size of the output voltage of the power regulator. Transformer secondary output voltage regulator, usually switching transformer, single around a set of coils, the voltage at its upper end, as the reference voltage after the rectifier filter, then through the optocoupler, this benchmark voltage return to the base of the oscillating tube pole to adjust the level of the oscillation frequency, if the transformer secondary voltage is increased, the sampling coil output voltage increases, the positive feedback voltage obtained through the optocoupler is also increased, this voltage is applied oscillating tube base, so that oscillation frequency is reduced, played a stable secondary output voltage stability, too small do not have to go into detail, nor it is necessary to understand the fine, such a high-power voltage transformer by switching transmission, separated and after the class returned by sampling the voltage from the opto-coupler pass separated after class, so before the mains voltage, and after the classseparation, which is called cold plate, it is safe, transformers before power is independent, which is called switching power supply.the DC / DC conversionDC / DC converter is a fixed DC voltage transformation into a variable DC voltage, also known as the DC chopper. There are two ways of working chopper, one Ts constant pulse width modulation mode, change the ton (General), the second is the frequency modulation, the same ton to change the Ts, (easy to produce interference). Circuit by the following categories:Buck circuit - the step-down chopper, the average output voltage U0 is less than the input voltage Ui, the same polarity.Boost Circuit - step-up chopper, the average output voltage switching power supply schematic U0 is greater than the input voltage Ui, the same polarity.Buck-Boost circuit - buck or boost chopper, the output average voltage U0 is greater than or less than the input voltage Ui, the opposite polarity, the inductance transmission.Cuk circuit - a buck or boost chopper, the output average voltage U0 is greater than or less than the input voltage Ui, the opposite polarity, capacitance transmission.The above-mentioned non-isolated circuit, the isolation circuit forward circuits, feedback circuit, the half-bridge circuit, the full bridge circuit, push-pull circuit. Today's soft-switching technology makes a qualitative leap in the DC / DC the U.S. VICOR company design and manufacture a variety of ECI soft-switching DC / DC converter, the maximum output power 300W, 600W, 800W, etc., the corresponding power density (6.2 , 10,17) W/cm3 efficiency (80-90)%. A the Japanese Nemic Lambda latest using soft-switching technology, high frequency switching power supply module RM Series, its switching frequency (200 to 300) kHz, power density has reached 27W/cm3 with synchronous rectifier (MOSFETs instead of Schottky diodes ), so that the whole circuit efficiency by up to 90%.AC / DC conversionAC / DC conversion will transform AC to DC, the power flow can be bi-directional power flow by the power flow to load known as the "rectification", referred to as "active inverter power flow returned by the load power. AC / DC converter input 50/60Hz AC due must be rectified, filtered, so the volume is relatively large filter capacitor is essential, while experiencing safety standards (such as UL, CCEE, etc.) and EMC Directive restrictions (such as IEC, FCC, CSA) in the AC input side must be added to the EMC filter and use meets the safety standards of the components, thus limiting the miniaturization of the volume of AC / DC power, In addition, due to internal frequency, high voltage, current switching, making the problem difficult to solve EMC also high demands on the internal high-density mountingcircuit design, for the same reason, the high voltage, high current switch makes power supply loss increases, limiting the AC / DC converter modular process, and therefore must be used to power system optimal design method to make it work efficiency to reach a certain level of satisfaction.AC / DC conversion circuit wiring can be divided into half-wave circuit, full-wave circuit. Press the power phase can be divided into single-phase three-phase, multiphase. Can be divided into a quadrant, two quadrant, three quadrants, four-quadrant circuit work quadrant.he selection of the switching power supplySwitching power supply input on the anti-jamming performance, compared to its circuit structure characteristics (multi-level series), the input disturbances, such as surge voltage is difficult to pass on the stability of the output voltage of the technical indicators and linear power have greater advantages, the output voltage stability up to (0.5)%. Switching power supply module as an integrated power electronic devices should be selected。
毕业设计英文翻译
沈阳工业大学化工装备学院毕业设计（论文）外文翻译毕业设计（论文）题目：含硫氨污水冷却器外文题目：Head processing technology译文题目：封头加工工艺院（系）：化工装备学院专业班级：过控0802班学生姓名：孙鹏博指导教师：闫小波2012年3月11日Head processing technology1.welding process1.1welding operationOur factory common welding methods are: manual welding, argon arc welding, submerged arc welding.(1) manual welding is mainly used for carbon steel 3-6mm plate welding.(2) submerged arc welding to more than 8mm carbon steel stainless steel sheet welding mainly.(3)3-6mm stainless steel argon arc welding with welding mainly. Commonly used stainless steel wire ER304and ER316L steel wire, commonly used to J422and J507and J426and J427low-temperature welding consumables. Flux of carbon steel used is the HJ431, stainless steel commonly used is HJ260,.As a result of welding wire flux can be easily affected with damp, stored in the infrared drying machine, flux HJ431and HJ260drying temperature is 250-300℃. Welding wire J422and J350drying temperature were 150℃ and 300 ℃Welding process is completely in accordance with the" welding" execution, sheet thickness determines the welding to welding or double sided arc welding in welding, after the weld seam inspection ( RT X ray ) judgment without pores, cracks and other defects, such as found in the above deficiencies, to the repair, until the filming.1.2 welding operation standard(1) welding procedure card after receiving process, affirm the process card and physical material, quantity, unit number, specifications, size instruction number is consistent, whether there is debris around the wafer, wafer splashes whether clean removal, such as treatment is not clean, will use the grinding clean.(2) there is no welding test plate, groove cutting quality can meet the requirement, material surface without obvious defects, such as abnormal response.(3) according to the" Regulations" welding procedure card check of welding groove type and dimensions correspond to.(4) on each side of groove surface grinding, butt edge offset is not greater than the10% thickness, and not more than1.5mm.(5) point fixed the first weld layer terminal welding length not less than 50mm, arc board specifications should be 150*150mm and a mask having R arc, team rounds should be given within 8 hours of welding, or to use flame to the moisture inside the baking groove.(6) the welder holds" welding" and" welding records" for welding consumables, welding two class library for registration, using flux field volume should not exceed 4 hours, or to continue to back into the oven drying.(7) a, preheating plate thickness not less than 30mm carbon steel, low alloy steel, the preheating temperature of welding process by" card"," standard" provisions of the welding technology.B, preheating range width not less than 4mm and no less than 100mm. C, in the process of welding groove at any time temperature shall not be less than the prescribed temperature.D, when welding temperature is below 0 ℃( arbitrary thickness) must be heated to 15 ℃or above in order to welding.(8) a before welding, welding to welding equipment inspection, examination was normal before welding facilities.According to B,"" the requirements of welding process welding, welding and fill in the recordsC, welding, welding layers shall be in accordance with" welding" requirements, welding shall not be a large current, less layers. (9) removal of the root a, stainless steel cleaning before the root groove sides, within the range of 300mm, splashing paint coating.B, using carbon arc air gouging, should be selected according to the request carbon rod diameter.C, root cleaning, grinding cleaning groove and two side the existence of carburized layer, oxide, slag and other sundries. Grinding width: manual welding, rust, oxide above 20mm, oil30mm above, automatic welding, rust, grease, oxides 25mm50mm groove inner grinding requirements, carbon steel, low alloy steelδn ≤10mm weld, its two ends within the range of 300mm carburized layer must be completely removed, the rest part allows the removal of more than 50%. Other non-ferrous metals must be completely clear. [3]D, root cleaning, composite steel Cr-Mo, manual welding and the thicknessofδn ≥30mm welds shall be examined by PT.(10) during the process of welding defect repair by welding repair welding repair monitor instruction experienced welders as. Repair welding process should eliminate soldering phenomenon, or polished after welding, the following defects must be removed before welding to welding crack,①partial②③pits the stomaA shall not be lower than the parent material, weld.B, there shall be no undercutting.C, without removing the residual high seam. The surface shall not have cracks, pores, crater, undercut and slag inclusions, and may not retain the slag and spatter.D, removal of residual high weld inspection shall not have any defect display PT.E, such as the defects of carbon steel, low-alloy steel repair procedures: a grinding wheel or a carbon arc gouging polishing cleaning→ PT check grinder grinding out the welding groove, welding, PT, stainless steel repair procedures: a grinding wheel or a carbon arc gouging polishing cleaning→PT (δ n≥ 2mm need )→grinder polished to a welding groove welding→ PT examination. [4](12) welded internal rework, repair procedures: location of defect, defect removal→ PT→→removal check welding weld→ PT examination. [5] (13) according to RT film, RT staff and the welders in welding seam together determine the location of defects, including the following requirements when using UT to determine the defect position, the first repairδ n≥ 30mm use UT to determine the location of defects, two or three repairδ n≥ 20mm using UT to determine the defect position, UT positioning by RT after class. The position and depth of defect ( calibration side shall be the depth of defect≤1/2 side).(14) after the welding inspector or monitor by confirmed, in the process card signed your name and object together with transfer to the next process, by the next process responsibility recognition can.2.stamping process2.1stamping operationStamping operation is small head forming an important operation. The same stamping is also head of the cracking, thinning appeared most processsection.2.2punching machine.(1) the master cylinder is mainly used to connect the die head, is the head forming the necessary parts.(2) side cylinder used for pressing die ring, fixing the upper and lower mold ring of head disk. The head in the pressing process is to prevent the crease, as an important part of the drum kit.(3) the overflow valve used for controlling the compressor overall pressure, prevent the wafer during the pressing process of tears. (4) stamping valve in pressure, stamping valve on pressure relief, achieve average pressure effect.In addition, circuit boards, motors, circuit boards, storage tank, operation platform, pedestal are stamping machine components.2.3.3 stamping operation steps(1) first of all to undertake a blanking process card, find a good wafer.(2) the control process card on the technological requirements, put ona set of corresponding die, and with the use of gauges to determine the selected die size and to suppress the wafer size.(3) the wafer is clamped on the upper and lower mold inside the circle, and determine the die head of the center point and the center point of the wafer in a straight line.(4) the operation ring mold and die relative motion, pressure test, according to the control rod rebound to judge the size of the pressure, thereby regulating pressure size.(5) pressure test end, pressed wafer, stamping.2.3the stamping operation standard(1) the control task orders, confirm physical and process card is consistent, according to the process card confirming workpiece number, material, specification, batch number and other factors, at the same time check wafer end there is no crack, burr, polished wafer whether it meets the requirements, whether chamfer, is facing the good, there are special requirements when the problem is found, in time to contact.(2) according to the process card correct selection of die mold surface, inspection, found bruises and serious injury must be polished, but must be clean mold surface corrosion and dirt.(3) according to the technology card size, shape, texture, straight edge higher to suppress.(4) the warm-stamping ( according to requirement sheet property is heated to a certain temperature, and then stamping process ), to prepare a baking gun, gas, oxygen, percussion with head shall prepare the corresponding template, double-sided film to the wafer edge of both sides in a range of about 200-300mm template removal, and clear the film surface. [6] (5) mounted on the lower die, as the case to join the die pad, the wafer inside and outside surface coated with oil, applied range of top to200-300mm, smear should be uniform, the upper and lower mold are evenly coated.(6) the first gold stamping head, hanging out with a model head, check section shape, at the same time, check whether the drum kit, and there is no thinning, and check the surface has no scratch, hoop printing, such as none of the above abnormalities can continue to stamping, head forming, sealing surfaces such as scratches are timely grinding, and confirm the minimum board thickness, confirm whether a scratch, strain, curved peel, orange peel, drum kits, wrinkle, hoop printing etc..(7) such as a head drum kit fold phenomenon should be together with the card with the move to rework process technology.(8) each head should be able to see the instruction, piece number, material, or to transplantation, each product specifications after testing, the process card ( to sign the name ) together to the next process, by the next process validation.3.pressure drum process3.1pressure drum operationPressure drum process and stamping processes are the same steps in the process, stamping process range of φ 159- φ1900mm and pressure drum process is in the range of φ 1600- φ4800mm. And stamping is different pressure drum mostly the head generally forming, eventually forming is completed by spinning, stamping without the special requirements of customers, eventually forming step is not required. φ 1600- φ1900mm heads the two processes is needed.3.2pressure drum machine.(1) the main cylinder is provided with an upper die head is pressed drumexecution as long as part of.(2) supporting seat fixed lower die and upper die head center in a straight line.(3) supporting frame1is provided with a rolling wheel, a position adjusting before and after.(4) supporting frame is provided with a rolling wheel rotating disk II. In addition, there are hydraulic system, the motor, oil pump, oil tank, and a control console.3.3pressure drum machine operation steps(1) first of all to undertake a blanking process card, find a good wafer.(2) the control process card on the technological requirements, put ona set of corresponding die, and with the use of gauges to determine the selected die size and to suppress the wafer size.(3) and stamping machine is different from the original film is not pressure drum center began to suppress, but from the wafer edge, as long as the die and wafer alignment on the line.(4) the pressing process is continuously by controlling the rotation wheel is driven by the rotation of a wafer rotating, according to a certain order to suppress.(5) in after the pressing process, prepared template matching. If a deviation to make further adjustments.3.4pressure drum operation standard(1) die on the quality of the products and the smooth pressure drum forming crucial. Therefore, require that the operator must according to the processing situation of choice for mold and timely adjust shim plate.(2) the operator receives the process card, see process card, according to the process card check objects, to confirm the real instruction, one-piece, material. Number, batch number etc.. According to the choice of mold process card.(3) for EHA, EHB head shapes have adopted the 0.82*D standard selection, for DHB, PSH, MD and other special products according to technology card selection of mold, but in principle according to P*0.82/1.15or P*0.82/1.2 standard selection. [1](4) pressing carefully before inspection wafer quality, no seam wafer end is smooth, there is no gap, surface has no cutting slag and defects.(5) a weld in addition to carefully check the end of the wafer wafer defects, at the same time should be checked for weld seam is higher than that of base metal, weld ends of are welding spatter, weld end grinding smooth, there is no crack notch.(6) two or two or more superimposed when pressed, each slice of the joint surface should be clean, according to the circumstances must entrust welding class, the wafer is welded together to suppress.(7) detection of wafer thickness ( the thickest, most thin, whether and process card, measurement of wafer size and process card.(8) suppression must be removed before the inside and outside surface of all debris, to prevent pitting appeared.(9) for general stainless steel materials ( more than 5mm plate ) using Teflon plate mold and the lower mold dressing on surface polished smooth ( necessary nowadays mold to Teflon plate. ) to ensure the surface quality of the workpiece, while in the process of the pressing need to avoid debris into molds and semi-finished products. [6](10) the pressing process, when the wafer is a R shape, must use the corresponding R model measurement, the pressing process should be considered to adjust the pressure deformation degree.(11) pressing is finished, the measurement of plate thickness, measuring arc length. Check surface quality, check end and weld end is smooth ( necessary to polish out the ceremony ).(12) to check the semi-finished product with process card is on the move to the next process ( and sign the name ) by the next process to confirm acceptance before.4.spinning process4.1spinning operationThe spinning process is pressed after the drum head molding process, mainly for large head R and straight edge formation.4.2spinning machine.(1) forming wheel is connected to the corresponding mold, forming in the head inside, mold top with half formed head R and straight edge is tangent to tangent.(2) supporting wheel is also connected and molded wheel mold, forming in the head outside, and a forming wheel tangent.(3) base for fixing head, and the bottom according to head size before and after moving, the head should be installed so that the center of the base and the head of the center in a straight line.(4) the center rod is used for fixing head, and the center and the center of the base is in a straight line.In addition to the motor, a circuit board, is connected to the shaft, anda control console.4.3spinning procedure(1) to undertake pressure drum process card, according to the card to determine the corresponding head spinning.(2) according to the head of the diameter, select the corresponding upper and lower mold.(3) the clamping head, ensure that the head of the center point and the center of the base point in a straight line.(4) to adjust the molding wheel and the head of tangent, then according to the forming wheel position adjustment roller.(5) in the spinning process to observe the forming roller and the supporting roller relative position, and continue to use the template on the line alignment. Until the R reaches the requirements.4.4spinning operation standard(1) spinning wheel material for steel bearings or ductile iron, mold on the quality of the products and can spin forming closely related, therefore the operator must be processed according to choose suitable mold, at the same time, because of the shape of the mold and the surface condition of the quality of the workpiece has a great influence, therefore, before processing and machining process must on the mold for full inspection.(2) according to the process card requirements, confirm wafer, pressure drum or preload semi-finished instruction number, specifications, quantity of material, compliance, and check the quality of surface and end with no defect, abnormal timely and on the procedures of contact, and in a timely manner(3) check the semi-finished end is smooth, with or without notch, crack, surface has no cutting or welding slag, and shall inspect the weld seam is higher than that of base metal, weld ends whether spatter, weld end grinding smooth, there is no crack. [7](4) pressure drum or to the press after the finished product, must checkfor folding, cracking, crack is not conducive to the spinning processing defects.(5) for stainless steel workpiece, through to the pickling method of decontamination.(6) according to the process card selection of mold, general small arc r size requirements as a basis for selecting the internal wheel. (7) according to the different material, thickness of plate and sheet rebound, selection is slightly smaller than the internal wheel circular arc R.(8) for the special requirements of the product, according to its shape design inside the wheel, confirm the mold surface, good polishing processing.(9) spinning processing, in order to prevent scratching and improve the processing performance, suitable lubricant ( grease ) to prevent process heating head appears on the surface of hot cracks and scratches, can also prolong the service life of die.(10) the spinning process, should be considered a workpiece shaping and timely for pressure adjustment.(11) after the molding process, deal with the size, shape, thickness, surface quality inspections, confirmation.(12) molded product with the card with the transfer process to the next process ( in the process card signed their name ) by the procedures under the inspector or monitor check before.5.groove processThe 5.1groove Essentials(1) groove process is a head of the data ( including circumference, total height) to achieve JB/T4746 standard key process. [1](2) groove is in order and cylinder head connection time, make welding more thoroughly.(3) the main groove cutting process and cutting process tools, is the use of plasma cutting.(4) cutting, according to the card on the technological requirements, determine groove type ( inner groove, outside the mouth, X groove ) and determine the groove angle.(5) the groove before the head splashing agent applicator.(6) groove when the first test slope, then a protractor measuring angle, identified in the tolerance range, after adjustment, the whole slope. The 5.2groove operation standard(1) according to the process card to find real, order confirmation No., specification, material, batch number, quantity and check whether the workpiece has a drum kit, crack, delamination, wrinkle, and whether the loss of a round, found problems in a timely manner to contact, processing, the plate thickness of more than 8mm, is suggested to lose the round groove, the following 6mm, tooling plate pressure is groove.(2) stainless steel head, should be in the groove wall smearing splash front head agent, prevent groove, slag spout to head on the wall. (3) head onto the beveling machine before, first confirm the head weight, based on the weight of suitable sling, sling safety inspection.(4) head onto the groove machine, beveling rotary table adjustment screw rod, with a center adjusting position, rotating table, is aligned to the center.(5) groove, according to technology card height and height tolerance groove height ruler to draw lines, confirm the high line, the slope slope, should first slope flat groove, and then the slope groove.(6) outside the mouth or the inner groove angle should be controlled within ± 2.5 tolerance.(7) groove after, should check the head circumference, height, straight edge, angle, if not qualified to repair process, repair.(8) qualified head will remove and clean the slag grinding head internal slag, together with card transfer to the next process ( and sign their name ) by the next process inspector confirmation can be.6.polishing process6.1 polishing process steps(1) according to the card process requirements, identify the need for polishing head.(2) the head rotating table, determine the level of, the clamping head.(3) polishing from edge to center, or from the center to the edge; according to the diameter size determine the head beam, lower speed and working stage, after moving speed.(4) check the polishing condition, appropriate for rework.The 6.2polishing operation standard(1) according to the process card and materials to confirm the product instruction number, specifications, material, batch number, quantity, and check whether the workpiece has a drum kit, crack, delamination defects, and whether the loss of a round, found problems in a timely manner to contact, processing, check the appearance, to determine the need for manual processing, the polishing before hook head to mark.(2) according to the requirements of the choice of using a polishing, polishing pads, and the necessary auxiliary tool.(3) confirm the head weight, based on the weight of suitable sling, and check whether the safety hanger.(4) the head hanging onto a work table, adjust the center, at the same time to ensure that the head is in the basic level (0-5 deviations ).(5) people in the scene when polishing polishing, attention, especially the left centre, speed fast, or outward from a center left, a little pressure to increase, from the edge to the center of pressure during polishing, to a little decrease in polishing head, thin wall, as the case may be mounted shockproof wheel, at the same time attention to mechanical work has no abnormal.(6) after the completion of inspection head polishing, with or without defect, and the necessary contact.(7) the Polish well head with coated packaging, in the process card signed their names, together with the head and process the card with the circulation storage, and by the next inspection approval.封头加工工艺1.焊接工序1.1 焊接操作我们厂常用的焊接方法有：手工焊、氩弧焊、埋弧焊。
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外文出处：《Exploiting Software How to Break Code》By Greg Hoglund, Gary McGraw Publisher : Addison Wesley Pub Date : February 17, 2004ISBN : 0-201-78695-8译文标题：JDBC接口技术译文：JDBC是一种可用于执行SQL语句的JavaAPI（ApplicationProgrammingInterface应用程序设计接口）。
它由一些Java语言编写的类和界面组成。
JDBC为数据库应用开发人员、数据库前台工具开发人员提供了一种标准的应用程序设计接口，使开发人员可以用纯Java语言编写完整的数据库应用程序。
一、ODBC到JDBC的发展历程说到JDBC，很容易让人联想到另一个十分熟悉的字眼“ODBC”。
它们之间有没有联系呢？如果有，那么它们之间又是怎样的关系呢？ODBC是OpenDatabaseConnectivity的英文简写。
它是一种用来在相关或不相关的数据库管理系统（DBMS）中存取数据的，用C语言实现的，标准应用程序数据接口。
通过ODBCAPI，应用程序可以存取保存在多种不同数据库管理系统（DBMS）中的数据，而不论每个DBMS使用了何种数据存储格式和编程接口。
1．ODBC的结构模型ODBC的结构包括四个主要部分：应用程序接口、驱动器管理器、数据库驱动器和数据源。
应用程序接口：屏蔽不同的ODBC数据库驱动器之间函数调用的差别，为用户提供统一的SQL编程接口。
驱动器管理器：为应用程序装载数据库驱动器。
数据库驱动器：实现ODBC的函数调用，提供对特定数据源的SQL请求。
如果需要，数据库驱动器将修改应用程序的请求，使得请求符合相关的DBMS所支持的文法。
数据源：由用户想要存取的数据以及与它相关的操作系统、DBMS和用于访问DBMS的网络平台组成。
虽然ODBC驱动器管理器的主要目的是加载数据库驱动器，以便ODBC函数调用，但是数据库驱动器本身也执行ODBC函数调用，并与数据库相互配合。
因此当应用系统发出调用与数据源进行连接时，数据库驱动器能管理通信协议。
当建立起与数据源的连接时，数据库驱动器便能处理应用系统向DBMS发出的请求，对分析或发自数据源的设计进行必要的翻译，并将结果返回给应用系统。
2．JDBC的诞生自从Java语言于1995年5月正式公布以来，Java风靡全球。
出现大量的用java语言编写的程序，其中也包括数据库应用程序。
由于没有一个Java语言的API，编程人员不得不在Java程序中加入C语言的ODBC函数调用。
这就使很多Java的优秀特性无法充分发挥，比如平台无关性、面向对象特性等。
随着越来越多的编程人员对Java语言的日益喜爱，越来越多的公司在Java程序开发上投入的精力日益增加，对java语言接口的访问数据库的API 的要求越来越强烈。
也由于ODBC的有其不足之处，比如它并不容易使用，没有面向对象的特性等等，SUN公司决定开发一Java语言为接口的数据库应用程序开发接口。
在JDK1．x 版本中，JDBC只是一个可选部件，到了JDK1．1公布时，SQL类包（也就是JDBCAPI）就成为Java语言的标准部件。
二、JDBC技术概述JDBC是一种可用于执行SQL语句的JavaAPI（ApplicationProgrammingInterface，应用程序设计接口）。
它由一些Java语言写的类、界面组成。
JDBC给数据库应用开发人员、数据库前台工具开发人员提供了一种标准的应用程序设计接口，使开发人员可以用纯Java语言编写完整的数据库应用程序。
通过使用JDBC，开发人员可以很方便地将SQL语句传送给几乎任何一种数据库。
也就是说，开发人员可以不必写一个程序访问Sybase，写另一个程序访问Oracle，再写一个程序访问Microsoft的SQLServer。
用JDBC写的程序能够自动地将SQL语句传送给相应的数据库管理系统（DBMS）。
不但如此，使用Java编写的应用程序可以在任何支持Java的平台上运行，不必在不同的平台上编写不同的应用。
Java和JDBC的结合可以让开发人员在开发数据库应用时真正实现“WriteOnce，RunEverywhere！”Java具有健壮、安全、易用等特性，而且支持自动网上下载，本质上是一种很好的数据库应用的编程语言。
它所需要的是Java应用如何同各种各样的数据库连接，JDBC正是实现这种连接的关键。
JDBC扩展了Java的能力，如使用Java和JDBCAPI就可以公布一个Web页，页中带有能访问远端数据库的Ap plet。
或者企业可以通过JDBC让全部的职工（他们可以使用不同的操作系统，如Windwos，Machintosh和UNIX）在Intranet上连接到几个全球数据库上，而这几个全球数据库可以是不相同的。
随着越来越多的程序开发人员使用Java语言，对Java访问数据库易操作性的需求越来越强烈。
MIS管理人员喜欢Java和JDBC，因为这样可以更容易经济地公布信息。
各种已经安装在数据库中的事务处理都将继续正常运行，甚至这些事务处理是存储在不同的数据库管理系统中；而对新的数据库应用来说，开发时间将缩短，安装和版本升级将大大简化。
程序员可以编写或改写一个程序，然后将它放在服务器上，而每个用户都可以访问服务器得到最新的版本。
对于信息服务行业，Java和JDBC提供了一种很好的向外界用户更新信息的方法。
1．JDBC的任务简单地说，JDBC能完成下列三件事：1）同一个数据库建立连接；2）向数据库发送SQL语句；3）处理数据库返回的结果。
2．JDBC—一种底层的APIJDBC是一种底层API，这意味着它将直接调用SQL命令。
JDBC完全胜任这个任务，而且比其他数据库互联更加容易实现。
同时它也是构造高层API和数据库开发工具的基础。
高层API和数据库开发工具应该是用户界面更加友好，使用更加方便，更易于理解的。
但所有这样的API将最终被翻译为象JDBC这样的底层API。
目前两种基于JDBC的高层API 正处在开发阶段。
1）SQL语言嵌入Java的预处理器。
虽然DBMS已经实现了SQL查询，但JDBC要求SQL 语句被当作字符串参数传送给Java程序。
而嵌入式SQL预处理器允许程序员将SQL语句混用：Java变量可以在SQL语句中使用，来接收或提供数值。
然后SQL的预处理器将把这种Java／SQL混用的程序翻译成带有JDBCAPI的Java程序。
2）实现从关系数据库到Java类的直接映射。
Javasoft和其他公司已经宣布要实现这一技术。
在这种“对象／关系”映射中，表的每一行都将变成这类的一个实例，每一列的值对应实例的一个属性。
程序员可以直接操作Java的对象；而存取所需要的SQL调用将在内部直接产生。
还可以实现更加复杂的映射，比如多张表的行在一个Java的类中实现。
随着大家对JDBC兴趣的不断浓厚，越来越多的开发人员已经开始利用JDBC为基础的工具进行开发。
这使开发工作变得容易。
同时，程序员也正在开发对最终用户来说访问数据库更加容易的应用程序。
3．JDBC和ODBC及其他API的比较到目前为止，微软的ODBC可能是用得最广泛的访问关系数据库的API。
它提供了连接几乎任何一种平台、任何一种数据库的能力。
那么，为什么不直接从Java中直接使用ODBC 呢？回答是可以从Java中使用ODBC，但最好在JDBC的协助下，用JDBC－ODBC桥接器实现。
那么，为什么需要JDBC呢？要回答这个问题，有这么几个方面：1）ODBC并不适合在Java中直接使用。
ODBC是一个C语言实现的API，从Java程序调用本地的C程序会带来一系列类似安全性、完整性、健壮性的缺点。
2）其次，完全精确地实现从C代码ODBC到JavaAPI写的ODBC的翻译也并不令人满意。
比如，Java没有指针，而ODBC中大量地使用了指针，包括极易出错的空指针“void＊”。
因此，对Java程序员来说，把JDBC设想成将ODBC转换成面向对象的API是很自然的。
3）ODBC并不容易学习，它将简单特性和复杂特性混杂在一起，甚至对非常简单的查询都有复杂的选项。
而JDBC刚好相反，它保持了简单事物的简单性，但又允许复杂的特性。
4）JDBC这样的JavaAPI对于纯Java方案来说是必须的。
当使用ODBC时，人们必须在每一台客户机上安装ODBC驱动器和驱动管理器。
如果JDBC驱动器是完全用Java语言实现的话，那么JDBC的代码就可以自动的下载和安装，并保证其安全性，而且，这将适应任何Java平台，从网络计算机NC到大型主机Mainframe。
总而言之，JDBCAPI是能体现SQL最基本抽象概念的、最直接的Java接口。
它建构在ODBC的基础上，因此，熟悉ODBC的程序员将发现学习JDBC非常容易。
JDBC保持了ODBC的基本设计特征。
实际上，这两种接口都是基于X／OPENSQL的调用级接口（CLI）。
它们的最大的不同是JDBC是基于Java的风格和优点，并强化了Java的风格和优点。
最近，微软又推出了除了ODBC以外的新的API，如RDO，ADO和OLEDB。
这些API事实上在很多方面上同JDBC一样朝着相同的方向努力，也就是努力成为一个面向对象的，基于ODBC的类接口。
然而，这些接口目前并不能代替ODBC，尤其在ODBC驱动器已经在市场完全形成的时候，更重要的是它们只是ODBC的“漂亮的包装”。
4．JDBC两层模型和三层模型JDBC支持两层模型，也支持三层模型访问数据库。
如图所示，两层模型中，一个java Appple或者一个JA－va应用直接同数据库连接。
这就需要能直接被访问的数据库进行连接的JDBC驱动器。
用户的SQL语句被传送给数据库，而这些语句执行的结果将被传回给用户。
数据库可以在同一机器上，也可以另一机器上通过网络进行连接。
这被称为“Client/Server”结构，用户的计算机作为Client,运行数据库的计算机作为Server。
这个网络可是intranet，比如连接全体雇员的企业内部网，当然也可以是internet。
如图所示，在三层模型中，命令将被发送到服务的“中间层”，而“中间层”将SQL 语句发送到数据库。
数据库处理SQL语句并将结果返回“中间层”，然后“中间层”将它们返回用户。
MIS管理员将发现三层模型很有吸引力，因为“中间层”可以进行对访问的控制并协同数据库的更新，另一个优势就是如果有一个“中间层”用户就可以使用一个易用的高层的API，这个API可以由“中间层”进行转换，转换成底层的调用。
而且，在许多情况下，三层模型可以提供更好的性能。