中文 外文文献翻译 毕业设计说明
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。
外文文献翻译的撰写说明
外文文献翻译的撰写说明
一、外文文献翻译的内容
通过外文文献查阅与翻译,进一步提高掌握使用外文的能力,熟悉本专业的主要的外文书刊,了解毕业设计(论文)课题的国内外信息与发展动向。
翻译的外文文献应主要选自学术期刊、学术会议的文章、有关著作及其他相关材料,应与毕业设计(论文)主题相关,并作为外文参考文献列入毕业设计(论文)的参考文献,中文译文后应附外文原文。
(一)标题应真实反映翻译外文的主体内容或原外文标题内容,一般控制在20个汉字以内。
可以用副标题对标题予以补充说明;
(二)标题下方正中为外文作者署名;
(三)外文翻译成中文的内容;
(四)外文著录。
二、字数要求
一般要求为2000-3000汉字或不少于15000外文字符。
三、打印格式
1、打印用纸:A4
2、页面设置:上:3.5cm;下:2.5 cm;左:3.0 cm;右2.4 cm;装订线:0.5cm;页眉:2.5 cm;页脚:1.8cm;行间距:固定值22磅
3、字体、字号:
大标题:黑体、三号;
小标题:黑体、四号;
正文部分:宋体、小四;
页眉“湖北理工学院外文文献翻译”,宋体、5号,居右排列;页码居页面底端靠右排列。
四、参考文献著录
参考文献著录按照GB7714-87文参考文献著录规则执行。
书写顺序为:序号.作者.论文名或著作名.杂志或会议名.卷号、期号或会议地点.出版社.页号.年。
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。
建筑学Modern-Architecture现代建筑大学毕业论文外文文献翻译及原文
建筑学Modern-Architecture现代建筑⼤学毕业论⽂外⽂⽂献翻译及原⽂毕业设计(论⽂)外⽂⽂献翻译⽂献、资料中⽂题⽬:现代建筑⽂献、资料英⽂题⽬:Modern Architecture⽂献、资料来源:⽂献、资料发表(出版)⽇期:院(部):专业:班级:姓名:学号:指导教师:翻译⽇期: 2017.02.14建筑学毕业设计的外⽂⽂献及译⽂⽂献、资料题⽬:《Advanced Encryption Standard》⽂献、资料发表(出版)⽇期:2004.10.25外⽂⽂献:Modern ArchitectureModern architecture, not to be confused with 'contemporary architecture', is a term given to a number of building styles with similar characteristics, primarily the simplification of form and the elimination of ornament. While the style was conceived early in the 20th century and heavily promoted by a few architects, architectural educators and exhibits, very few Modern buildings were built in the first half of the century. For three decades after the Second World War, however, it became the dominant architectural style for institutional and corporate building.1. OriginsSome historians see the evolution of Modern architecture as a social matter, closely tied to the project of Modernity and hence to the Enlightenment, a result of social and political revolutions.Others see Modern architecture as primarily driven by technological and engineering developments, and it is true that the availability of new building materials such as iron, steel, concrete and glass drove the invention of new building techniques as part of the Industrial Revolution. In 1796, Shrewsbury mill owner Charles Bage first used his ‘fireproof’ design, which relied on cast iron and brick with flag stone floors. Such construction greatly strengthened the structure of mills, which enabled them to accommodate much bigger machines. Due to poor knowledge of iron's properties as a construction material, a number of early mills collapsed. It was not until the early 1830s that Eaton Hodgkinson introduced the section beam, leading to widespread use of iron construction, this kind of austere industrial architecture utterly transformed the landscape of northern Britain, leading to the description, "Dark satanic mills" of places like Manchester and parts of West Yorkshire. The Crystal Palace by Joseph Paxton at the Great Exhibition of 1851 was an early example of iron and glass construction; possibly the best example is the development of the tall steel skyscraper in Chicago around 1890 by William Le Baron Jenney and Louis Sullivan. Early structures to employ concrete as the chief means of architectural expression (rather than for purely utilitarian structure) include Frank Lloyd Wright's Unity Temple, built in 1906 near Chicago, and Rudolf Steiner's Second Goetheanum, built from1926 near Basel, Switzerland.Other historians regard Modernism as a matter of taste, a reaction against eclecticism and the lavish stylistic excesses of Victorian Era and Edwardian Art Nouveau.Whatever the cause, around 1900 a number of architects around the world began developing new architectural solutions to integrate traditional precedents (Gothic, for instance) with new technological possibilities. The work of Louis Sullivan and Frank Lloyd Wright in Chicago, Victor Horta in Brussels, Antoni Gaudi in Barcelona, Otto Wagner in Vienna and Charles Rennie Mackintosh in Glasgow, among many others, can be seen as a common struggle between old and new.2. Modernism as Dominant StyleBy the 1920s the most important figures in Modern architecture had established their reputations. The big three are commonly recognized as Le Corbusier in France, and Ludwig Mies van der Rohe and Walter Gropius in Germany. Mies van der Rohe and Gropius were both directors of the Bauhaus, one of a number of European schools and associations concerned with reconciling craft tradition and industrial technology.Frank Lloyd Wright's career parallels and influences the work of the European modernists, particularly via the Wasmuth Portfolio, but he refused to be categorized with them. Wright was a major influence on both Gropius and van der Rohe, however, as well as on the whole of organic architecture.In 1932 came the important MOMA exhibition, the International Exhibition of Modern Architecture, curated by Philip Johnson. Johnson and collaborator Henry-Russell Hitchcock drew together many distinct threads and trends, identified them as stylistically similar and having a common purpose, and consolidated them into the International Style.This was an important turning point. With World War II the important figures of the Bauhaus fled to the United States, to Chicago, to the Harvard Graduate School of Design, and to Black Mountain College. While Modern architectural design never became a dominant style in single-dwelling residential buildings, in institutional and commercial architecture Modernism became the pre-eminent, and in the schools (for leaders of the profession) the only acceptable, design solution from about 1932 to about 1984.Architects who worked in the international style wanted to break with architectural tradition and design simple, unornamented buildings. The most commonly used materials are glass for the facade, steel for exterior support, and concrete for the floors and interior supports; floor plans were functional and logical. The style became most evident in the design of skyscrapers. Perhaps its most famous manifestations include the United Nations headquarters (Le Corbusier, Oscar Niemeyer, Sir Howard Robertson), the Seagram Building (Ludwig Mies van der Rohe), and Lever House (Skidmore, Owings, and Merrill), all in New York. A prominent residential example is the Lovell House (Richard Neutra) in Los Angeles.Detractors of the international style claim that its stark, uncompromisingly rectangular geometry is dehumanising. Le Corbusier once described buildings as "machines for living", but people are not machines and it was suggested that they do not want to live in machines. Even Philip Johnson admitted he was "bored with the box." Since the early 1980s many architects have deliberately sought to move away from rectilinear designs, towards more eclectic styles. During the middle of the century, some architects began experimenting in organic forms that they felt were more human and accessible. Mid-century modernism, or organic modernism, was very popular, due to its democratic and playful nature. Alvar Aalto and Eero Saarinen were two of the most prolific architects and designers in this movement, which has influenced contemporary modernism.Although there is debate as to when and why the decline of the modern movement occurred, criticism of Modern architecture began in the 1960s on the grounds that it was universal, sterile, elitist and lacked meaning. Its approach had become ossified in a "style" that threatened to degenerate into a set of mannerisms. Siegfried Giedion in the 1961 introduction to his evolving text, Space, Time and Architecture (first written in 1941), could begin "At the moment a certain confusion exists in contemporary architecture, as in painting; a kind of pause, even a kind of exhaustion." At the Metropolitan Museum of Art, a 1961 symposium discussed the question "Modern Architecture: Death or Metamorphosis?" In New York, the coup d'état appeared to materialize in controversy around the Pan Am Building that loomed over Grand Central Station, taking advantage of the modernist real estate concept of "air rights",[1] In criticism by Ada Louise Huxtable and Douglas Haskell it was seen to "sever" the Park Avenue streetscape and "tarnish" the reputations of its consortium of architects: Walter Gropius, Pietro Belluschi and thebuilders Emery Roth & Sons. The rise of postmodernism was attributed to disenchantment with Modern architecture. By the 1980s, postmodern architecture appeared triumphant over modernism, including the temple of the Light of the World, a futuristic design for its time Guadalajara Jalisco La Luz del Mundo Sede International; however, postmodern aesthetics lacked traction and by the mid-1990s, a neo-modern (or hypermodern) architecture had once again established international pre-eminence. As part of this revival, much of the criticism of the modernists has been revisited, refuted, and re-evaluated; and a modernistic idiom once again dominates in institutional and commercial contemporary practice, but must now compete with the revival of traditional architectural design in commercial and institutional architecture; residential design continues to be dominated by a traditional aesthetic.中⽂译⽂:现代建筑现代建筑,不被混淆与'当代建筑' , 是⼀个词给了⼀些建筑风格有类似的特点, 主要的简化形式,消除装饰等. 虽然风格的设想早在20世纪,并⼤量造就了⼀些建筑师、建筑教育家和展品,很少有现代的建筑物,建于20世纪上半叶. 第⼆次⼤战后的三⼗年, 但最终却成为主导建筑风格的机构和公司建设.1起源⼀些历史学家认为进化的现代建筑作为⼀个社会问题, 息息相关的⼯程中的现代性,从⽽影响了启蒙运动,导致社会和政治⾰命.另⼀些⼈认为现代建筑主要是靠技术和⼯程学的发展, 那就是获得新的建筑材料,如钢铁, 混凝⼟和玻璃驱车发明新的建筑技术,它作为⼯业⾰命的⼀部分. 1796年, shrewsbury查尔斯bage⾸先⽤他的'⽕'的设计, 后者则依靠铸铁及砖与⽯材地板. 这些建设⼤⼤加强了结构,使它们能够容纳更⼤的机器. 由于作为建筑材料特性知识缺乏,⼀些早期建筑失败. 直到1830年初,伊顿Hodgkinson预计推出了型钢梁, 导致⼴泛使⽤钢架建设,⼯业结构完全改变了这种窘迫的⾯貌,英国北部领导的描述, "⿊暗魔⿁作坊"的地⽅如曼彻斯特和西约克郡. ⽔晶宫由约瑟夫paxton的重⼤展览, 1851年,是⼀个早期的例⼦,钢铁及玻璃施⼯; 可能是⼀个最好的例⼦,就是1890年由William乐男爵延长和路易沙利⽂在芝加哥附近发展的⾼层钢结构摩天楼. 早期结构采⽤混凝⼟作为⾏政⼿段的建筑表达(⽽⾮纯粹功利结构) ,包括建于1906年在芝加哥附近,劳埃德赖特的统⼀宫, 建于1926年瑞⼠巴塞尔附近的鲁道夫斯坦纳的第⼆哥特堂,.但⽆论原因为何, 约有1900多位建筑师,在世界各地开始制定新的建筑⽅法,将传统的先例(⽐如哥特式)与新的技术相结合的可能性.路易沙利⽂和赖特在芝加哥⼯作,维克多奥尔塔在布鲁塞尔,安东尼⾼迪在巴塞罗那, 奥托⽡格纳和查尔斯景mackintosh格拉斯哥在维也纳,其中之⼀可以看作是⼀个新与旧的共同⽃争.2现代主义风格由1920年代的最重要⼈物,在现代建筑⾥确⽴了⾃⼰的名声. 三个是公认的柯布西耶在法国, 密斯范德尔德罗和⽡尔特格罗⽪乌斯在德国. 密斯范德尔德罗和格罗⽪乌斯为董事的包豪斯, 其中欧洲有不少学校和有关团体学习调和⼯艺和传统⼯业技术.赖特的建筑⽣涯中,也影响了欧洲建筑的现代艺术,特别是通过⽡斯穆特组合但他拒绝被归类与他们. 赖特与格罗⽪乌斯和Van der德罗对整个有机体系有重⼤的影响.在1932年来到的重要moma展览,是现代建筑艺术的国际展览,艺术家菲利普约翰逊. 约翰逊和合作者亨利-罗素阁纠集许多鲜明的线索和趋势, 内容相似,有⼀个共同的⽬的,巩固了他们融⼊国际化风格这是⼀个重要的转折点. 在⼆战的时间包豪斯的代表⼈物逃到美国,芝加哥,到哈佛⼤学设计⿊⼭书院. 当现代建筑设计从未成为主导风格单⼀的住宅楼,在成为现代卓越的体制和商业建筑, 是学校(专业领导)的唯⼀可接受的, 设计解决⽅案,从约1932年⾄约1984年.那些从事国际风格的建筑师想要打破传统建筑和简单的没有装饰的建筑物。
山东建筑大学本科毕业设计说明书外文文献及翻译格式模版1.doc
山东建筑大学本科毕业设计说明书外文文献及翻译格式模版1附件3:(本科毕业论文)文献、资料题目:院(部)专班姓名:张三学号:指导教师:张九光翻译日期:2005.6.30,the National Institute of Standards and Technology (NIST) has been working to develop a new encryption standard to keep government information secure .The organization is in the final stages of an open process of selecting one or more algorithms ,or data-scrambling formulas ,for the new Advanced Encryption Standard (AES) and plans to make adecision by late summer or early fall .The standard is slated to go into effect next year .AES is intended to be a stronger ,more efficient successor to Triple Data Encryption Standard (3DES),which replaced the aging DES ,which was cracked in less than three days in July 1998.“Until we have the AES ,3DES will still offer protection for years to come .So there is no need to immediately switch over ,”says Edward Roback ,acting chief of the computer security division at NIST and chairman of the AES selection committee .“What AES will offer is a more efficient algorithm .It will be a federal standard ,but it will be widely implemented in the IT community .”According to Roback ,efficiency of the proposed algorithms is measured by how fast they can encrypt and decrypt information ,how fast they can present an encryption key and how much information they can encrypt .The AES review committee is also looking at how much space the algorithm takes up on a chip and how much memory it requires .Roback says the selection of a more efficient AES will also result in cost savings and better use of resources .“DES w as designed for hardware implementations ,and we are now living in a world of much more efficient software ,and we have learned an awful lot about the design of algorithms ,”says Roback .“When you start multiplying this with the billions of implementations done daily ,the saving on overhead on the networks will be enormous .”……山东建筑大学毕业设计(或毕业论文,二选一)外文文献及译文- 1 -以确保政府的信息安全。
教育毕业设计说明范文
教育毕业设计说明范文As a student, the education graduation project holds a significant weight in my academic journey. 作为学生,教育毕业设计在我的学术之旅中扮演着重要的角色。
The education graduation project is not only a culmination of four years of hard work, but also a reflection of my passion and dedication to the field of education. 教育毕业设计不仅是四年努力的结晶,也是我对教育领域的热情和奉献的体现。
Through my education graduation project, I have the opportunity to delve deeper into a subject that interests me and make a meaningful contribution to the field. 通过我的教育毕业设计,我有机会更深入地研究我感兴趣的课题,并对该领域做出有意义的贡献。
One of the challenges I faced during my education graduation project was time management. 在我进行教育毕业设计期间面临的一个挑战是时间管理。
Balancing coursework, part-time work, and social commitments while working on my education graduation project required careful planning and organization. 在进行教育毕业设计的同时,平衡课程作业、兼职工作和社交活动需要细心的计划和组织。
外文文献翻译——参考格式
广东工业大学华立学院本科毕业设计(论文)外文参考文献译文及原文系部经济学部专业经济学年级 2007级班级名称 07经济学6班学号 16020706001学生姓名张瑜琴指导教师陈锶2011 年05月目录1挑战:小额贷款中的进入和商业银行的长期承诺 (1)2什么商业银行带给小额贷款和什么把他们留在外 (2)3 商业银行的四个模型进入小额贷款之内 (4)3.1内在的单位 (4)3.2财务子公司 (5)3.3策略的同盟 (5)3.4服务公司模型 (6)4 合法的形式和操作的结构比较 (8)5 服务的个案研究公司模型:厄瓜多尔和Haiti5 (9)1 挑战:小额贷款中的进入和商业银行的长期承诺商业银行已经是逐渐重要的运动员在拉丁美洲中的小额贷款服务的发展2到小额贷款市场是小额贷款的好消息客户因为银行能提供他们一完整类型的财务的服务,包括信用,储蓄和以费用为基础的服务。
整体而言,它也对小额贷款重要,因为与他们广泛的身体、财务的和人类。
如果商业银行变成重的运动员在小额贷款,他们能提供非常强烈的竞争到传统的小额贷款机构。
资源,银行能廉宜地发射而且扩张小额贷款服务rela tively。
如果商业广告银行在小额贷款中成为严重的运动员,他们能提出非常强烈的竞争给传统的小额贷款机构。
然而,小额贷款社区里面有知觉哪一商业银行进入进入小额贷款将会是短命或浅的。
举例来说,有知觉哪一商业银行首先可能不搬进小额贷款因为时候建立小额贷款操作到一个有利润的水平超过银行的标准投资时间地平线。
或,在进入小额贷款,银行之后可能移动在-上面藉由增加贷款数量销售取利润最大值-或者更坏的事,退出如果他们是不满意与小额贷款的收益性的水平。
这些知觉已经被特性加燃料商业银行的情形进入小额贷款和后来的出口之内。
在最极端的,一些开业者已经甚至宣布,”降低尺度死!”而且抛弃了与主意合作的商业银行。
在最 signific 看得到的地方,蚂蚁利益商业银行可能带给小额贷款,国际的ACCION 发展发射而且扩张的和一些商业银行的关系小额贷款操作。
毕业设计论文中英文翻译要求(最新)
附件1(毕业设计一)材料科学与工程学院毕业实习环节外文翻译要求一、翻译论文的选择:1、与自己毕业设计相关的外文参考文献2、该译文可以作为设计论文中文献综述中的部分内容;3、原则上选取的英语原文不超过5页。
二、译文结构内容1、作者,英文原文题目,期刊名称,卷期号,年份,起止页码,2、文章题目,作者(保持英文,不需翻译),作者单位(英文不变)3、摘要,关键词4、正文部分:引言,试验过程,结果与讨论,结论,参考文献(保持原文状态)5、译文中的图标需要翻译,图可以复印后粘贴或扫描插入三、译文和原文统一装订在一起,独立与毕业论文一起上交四、几点附属说明1 文章所在期刊的期刊名及相关信息不要翻译。
2 文章的作者,作者的单位,地址,下注的通讯作者的情况,参考文献不要翻译。
3文章的题目,摘要,关键词,及正文都要按照原文的顺序来翻译。
4文章中图表翻译示例如下:此为翻译前的表格:此为翻译后的表格:表1 微波和常规方法加工的粉体金属样品的性能Table 1 Properties of microwave and conventionally processedpowdered metal samplesMW 代表微波烧结;conv代表常规方法。
大部分微波烧结的样品的断裂模量比常规方法烧结的要高。
许多微波烧结的样品的密度也是高于常规方法烧成的样品。
MW, microwave processed; conv., conventionally processed. Themodulus of rupture(MOR) of most microwave-processed samples ishigher than that of the conventional samples. The densities of manymicrowave-processed samples are also higher than those ofconventional samples.即表头和注释中英文都要。
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。
毕业设计论文化学系毕业论文外文文献翻译中英文
毕业设计论文化学系毕业论文外文文献翻译中英文英文文献及翻译A chemical compound that is contained in the hands of the problemsfor exampleCatalytic asymmetric carbon-carbon bond formation is one of the most active research areas in organic synthesis In this field the application of chiral ligands in enantioselective addition of diethylzinc to aldehydes has attracted much attention lots of ligands such as chiral amino alcohols amino thiols piperazines quaternary ammonium salts 12-diols oxazaborolidines and transition metal complex with chiral ligands have been empolyed in the asymmetric addition of diethylzinc to aldehydes In this dissertation we report some new chiral ligands and their application in enantioselective addition of diethylzinc to aldehydes1 Synthesis and application of chiral ligands containing sulfur atomSeveral a-hydroxy acids were prepared using the literature method with modifications from the corresponding amino acids valine leucine and phenylalanine Improved yields were obtained by slowly simultaneous addition of three fold excess of sodium nitrite and 1 tnolL H2SO4 In the preparation of a-hydroxy acid methyl esters from a-hydroxy acids following the procedure described by Vigneron a low yield 45 was obtained It was found that much better results yield 82 couldbe obtained by esterifying a-hydroxy acids with methanol-thionyl chlorideThe first attempt to convert S -2-hydroxy-3-methylbutanoic acid methyl ester to the corresponding R-11-diphenyl-2-mercapto-3-methyl-l-butanol is as the following S-2-Hydroxy-3-methylbutanoic acid methyl ester was treated with excess of phenylmagnesium bromide to give S -11-diphenyl-3-methyl-12-butanediol which was then mesylated to obtain S -11-diphenyl-3-methyl-2-methanesulfonyloxy -l-butanol Unfortunately conversion of S-11-diphenyl-3-methyl-2- methanesulfonyloxy -l-butanol to the corresponding thioester by reacting with potassium thioacetate under Sn2 reaction conditions can be achieved neither in DMF at 20-60 nor in refluxing toluene in the presence of 18-crown-6 as catalyst When S -1ll-diphenyl-3-methyl-2- methane sulfonyloxy -l-butanol was refluxed with thioacetic acid in pyridine an optical active epoxide R-22-diphenyl -3-isopropyloxirane was obtained Then we tried to convert S -11-diphenyl-3-methyl-l2-butanediol to the thioester by reacting with PPh3 DEAD and thioacetic acid the Mitsunobu reaction but we failed either probably due to the steric hindrance around the reaction centerThe actually successful synthesis is as described below a-hydroxy acid methyl esters was mesylated and treated with KSCOCH3 in DMF to give thioester this was than treated with phenyl magnesium bromide to gave the target compound B-mercaptoalcohols The enantiomeric excesses ofp-mercaptoalcohols can be determined by 1H NMR as their S -mandeloyl derivatives S -2-amino-3-phenylpropane-l-thiol hydrochloride was synthesized from L-Phenylalanine L-Phenylalanine was reduced to the amino alcohol S -2-amino-3-phenylpropanol Protection of the amino group using tert-butyl pyrocarbonate gave S -2-tert-butoxycarbonylamino-3-phenylpropane-l-ol which was then O-mesylated to give S -2-tert-butoxycarbonylamino-3-phenylpropyl methanesulfonate The mesylate was treated with potassium thioacetate in DMF to give l-acetylthio-2-tert-butoxycarbonylamino-3-phenylpropane The acetyl group was then removed by treating with ammonia in alcohol to gave S -2-tert-butoxycarbonylamino-3-phenyl-propane-l-thiol which was then deprotected with hydrochloric acid to give the desired S-2-amino-3-phenylpropane-1-thiol hydrochlorideThe enantioselective addition of diethylzinc to aldehydes promoted by these sulfur containing chiral ligands produce secondary alcohols in 65-79 Synthesis and application of chiral aminophenolsThree substituted prolinols were prepared from the naturally-occurring L-proline using reported method with modifications And the chiral aminophenols were obtained by heating these prolinols with excess of salicylaldehyde in benzene at refluxThe results of enantioselective adBelow us an illustration forexampleN-Heterocyclic carbenes and L-Azetidine-2-carboxylicacidN-Heterocyclic carbenesN-Heterocyclic carbenes have becomeuniversal ligands in organometallic and inorganic coordination chemistry They not only bind to any transition metal with low or high oxidation states but also to main group elements such as beryllium sulfur and iodine Because of their specific coordination chemistry N-heterocyclic carbenes both stabilize and activate metal centers in quite different key catalytic steps of organic syntheses for example C-H activation C-C C-H C-O and C-N bond formation There is now ample evidence that in the new generation of organometallic catalysts the established ligand class of organophosphanes will be supplemented and in part replaced byN-heterocyclic carbenes Over the past few years this chemistry has become the field of vivid scientific competition and yielded previously unexpected successes in key areas of homogeneous catalysis From the work in numerous academic laboratories and in industry a revolutionary turningpoint in oraganometallic catalysis is emergingIn this thesis Palladium Ⅱ acetate and NN"-bis- 26-diisopropylphenyl dihydro- imidazolium chloride 1 2 mol were used to catalyze the carbonylative coupling of aryl diazonium tetrafluoroborate salts and aryl boronic acids to form aryl ketones Optimal conditions include carbon monoxide 1 atm in 14-dioxane at 100℃ for 5 h Yields for unsymmetrical aryl ketones ranged from 76 to 90 for isolated materials with only minor amounts of biaryl coupling product observed 2-12 THF as solvent gave mixtures of products 14-Dioxane proved to be the superior solvent giving higher yieldsof ketone product together with less biphenyl formation At room temperature and at 0℃ with 1 atm CO biphenyl became the major product Electron-rich diazonium ion substrates gave a reduced yield with increased production of biaryl product Electron-deficient diazonium ions were even better forming ketones in higher yields with less biaryl by-product formed 2-Naphthyldiazonium salt also proved to be an effective substrate givingketones in the excellent range Base on above palladium NHC catalysts aryl diazonium tetrafluoroborates have been coupled with arylboron compounds carbon monoxide and ammonia to give aryl amides in high yields A saturated yV-heterocyclic carbene NHC ligand H2lPr 1 was used with palladium II acetate to give the active catalyst The optimal conditions with 2mol palladium-NHC catalyst were applied with various organoboron compounds and three aryl diazonium tetrafluoroborates to give numerous aryl amides in high yield using pressurized CO in a THF solution saturated with ammonia Factors that affect the distribution of the reaction products have been identified and a mechanism is proposed for this novel four-component coupling reactionNHC-metal complexes are commonly formed from an imidazolium salt using strong base Deprotonation occurs at C2 to give a stable carbene that adds to form a a-complex with the metal Crystals were obtained from the reaction of imidazolium chloride with sodium t- butoxide Nal and palladium II acetate giving a dimeric palladium II iodide NHC complex The structure adopts a flat 4-memberedring u2 -bridged arrangement as seen in a related dehydro NHC complex formed with base We were pleased to find that chloride treated with palladium II acetate without adding base or halide in THF also produced suitable crystals for X-ray anaysis In contrast to the diiodide the palladium-carbenes are now twisted out of plane adopting a non-planar 4-ring core The borylation of aryldiazonium tetrafluoroborates with bis pinacolatoborane was optimized using various NHC ligand complexes formed in situ without adding base NN"-Bis 26-diisopropylphenyl-45-dihydroimidazolium 1 used with palladium acetate in THF proved optimal giving borylated product in 79 isolated yield without forming of bi-aryl side product With K2CO3 and ligand 1 a significant amount of biaryl product 24 was again seen The characterization of the palladium chloride complex by X-ray chrastallography deL-Azetidine-2-carboxylic acidL-Azetidine-2-carboxylic acid also named S -Azetidine-2-carboxylic acid commonly named L-Aze was first isolated in 1955 by Fowden from Convallaria majalis and was the first known example of naturally occurring azetidine As a constrained amino acid S -Azetidine-2-carboxylic acid has found many applications in the modification of peptides conformations and in the area of asymmetric synthesis which include its use in the asymmetric reduction of ketones Michael additions cyclopropanations and Diels-Alder reactions In this dissertation five ways for synthesize S-Azetidine-2-carboxylic acid were studied After comparing all methods theway using L-Aspartic acid as original material for synthesize S-Azetidine-2-carboxylic acid was considered more feasible All mechanisms of the way"s reaction have also been studied At last the application and foreground of S -Azetidine-2-carboxylic acid were viewed The structures of the synthetic products were characterized by ThermalGravity-Differential Thermal Analysis TG-DTA Infrared Spectroscopy IR Mass Spectra MS and 1H Nuclear Magnetic Resonance 1H-NMR Results showed that the structures and performances of the products conformed to the anticipation the yield of each reaction was more than 70 These can conclude that the way using L-Aspartie acid as original material for synthesize S -Azetidine-2-carboxylic acid is practical and effective杂环化合物生成中包含手性等问题如催化形成不对称碳碳键在有机合成中是一个非常活跃的领域在这个领域中利用手性配体诱导的二乙基锌和醛的不对称加成引起化学家的广泛关注许多手性配体如手性氨基醇手性氨基硫醇手性哌嗪手性四季铵盐手性二醇手性恶唑硼烷和过渡金属与手性配体的配合物等被应用于二乙基锌对醛的不对称加成中在本论文中我们报道了一些新型的手性配体的合成及它们应用于二乙基锌对醛的不对称加成的结果1含硫手性配体的合成和应用首先从氨基酸缬氨酸亮氨酸苯丙氨酸出发按照文献合成α-羟基酸并发现用三倍量的亚硝酸钠和稀硫酸同时滴加进行反应能适当提高反应的产率而根据Vigneron等人报道的的方法用浓盐酸催化从α-羟基酸合成α-羟基酸甲酯时只能获得较低的产率改用甲醇-二氯亚砜的酯化方法时能提高该步骤的产率从 S -3-甲基-2-羟基丁酸甲酯合成 R -3-甲基-11-二苯基-2-巯基-1-丁醇经过了以下的尝试 S -3-甲基-2-羟基丁酸甲酯和过量的格氏试剂反应得到 S -3-甲基-11-二苯基-12-丁二醇进行甲磺酰化时位阻较小的羟基被磺酰化生成 S -3-甲基-11-二苯基-2- 甲磺酰氧基 -1-丁醇但无论将 S -3-甲基-11-二苯基-2- 甲磺酰氧基 -1-丁醇和硫代乙酸钾在DMF中反应 20~60℃还是在甲苯中加入18-冠-6作为催化剂加热回流都不能得到目标产物当其与硫代乙酸在吡啶中回流时得到的不是目标产物而是手性环氧化合物 R -3-异丙基-22-二苯基氧杂环丙烷从化合物 S -3-甲基-11-二苯基-12-丁二醇通过Mitsunobu反应合成硫代酯也未获得成功这可能是由于在反应中心处的位阻较大造成的几奥斯塑手村犯体的合成裁其在不对称奋成中肠左用摘要成功合成疏基醇的合成路是将a-轻基酸甲酷甲磺酞化得到相应的磺酞化产物并进行与硫代乙酸钾的亲核取代反应得到硫酷进行格氏反应后得到目标分子p一疏基醇用p一疏基醇与 R 义一一甲氧基苯乙酞氯生成的非对映体经H侧NM吸测试其甲氧基峰面积的积分求得其ee值 3一苯基一氨基丙硫醇盐酸盐从苯丙氨酸合成斗3一苯基一氨基丙醇由L一苯丙氨酸还原制备氨基保护后得到习一3一苯基一2一叔丁氧拨基氨基一1一丙醇甲磺酞化后得到习一3一苯基一2一叔丁氧拨基氨基一1一丙醇甲磺酸酷用硫代乙酸钾取代后得匀一3-苯基一2一叔丁氧拨基氨基一1一丙硫醇乙酸酷氨解得习一3一苯基一2一叔丁氧拨基氨基一1一丙硫醇用盐酸脱保护后得到目标产物扔3一苯基屯一氨基丙硫醇盐酸盐手性含硫配体诱导下的二乙基锌与醛的加成所得产物的产率为65一79值为O井92手性氨基酚的合成和应用首先从天然的L一脯氨酸从文献报道的步骤合成了三种脯氨醇这些手性氨基醇与水杨醛在苯中回流反应得到手性氨基酚手性氨基酚配体诱导下的二乙基锌与醛的加成所得产物的产率为45一98值为0一90手性二茂铁甲基氨基醇的合成和应用首先从天然氨基酸绿氨酸亮氨酸苯丙氨酸和脯氨酸合成相应的氨基醇这些氨基醇与二茂铁甲醛反应生成的NO一缩醛经硼氢化钠还原得到手性二茂铁甲基氨基醇手性二茂铁甲基氨基醇配体诱导下的二乙基锌与醛的加成所得产物的产率为66一97下面我们举例说明一下例如含氮杂环卡宾和L-氮杂环丁烷-2-羧酸含氮杂环卡宾含氮杂环卡宾已广泛应用于有机金属化学和无机配合物化学领域中它们不仅可以很好地与任何氧化态的过渡金属络合还可以与主族元素铍硫等形成配合物由于含氮杂环卡宾不但使金属中心稳定而且还可以活化此金属中心使其在有机合成中例如C-H键的活化C-CC-HC-O和C-N键形成反应中有着十分重要的催化效能现有的证据充分表明在新一代有机金属催化剂中含氮杂环卡宾不但对有机膦类配体有良好的互补作用而且在有些方面取代有机膦配体成为主角近年来含氮杂环卡宾及其配合物已成为非常活跃的研究领域在均相催化这一重要学科中取得了难以想象的成功所以含氮杂环卡宾在均相有机金属催化领域的研究工作很有必要深入地进行下去本文研究了乙酸钯和NN双 26-二异丙基苯基 -45-二氢咪唑氯化物1作为催化剂催化芳基四氟硼酸重氮盐与芳基硼酸的羰基化反应合成了一系列二芳基酮并对反应条件进行了优化使反应在常温常压下进行一个大气压的一氧化碳14-二氧杂环己烷作溶剂100℃反应5h 不同芳基酮的收率达7690仅有微量的联芳烃付产物 212 反应选择性良好当采用四氢呋喃或甲苯作溶剂时得到含较多副产物的混合物由此可以证明14-二氧杂环己烷是该反应最适宜的溶剂在室温或0℃与一个大气压的一氧化碳反应联芳烃变成主产物含供电子取代基的芳基重氮盐常常给出较低收率的二芳基酮而含吸电子取代基的芳基重氮盐却给出更高收率的二芳基酮及较少量的联芳烃付产物实验证明2-萘基重氮盐具有很好的反应活性和选择性总是得到优异的反应结果在此基础上由不同的芳基四氟硼酸重氮盐与芳基硼酸一氧化碳和氨气协同作用以上述含氮杂环卡宾作配体与乙酸钯生成的高活性含氮杂环卡宾钯催化剂催化较高收率地得到了芳基酰胺优化的反应条件是使用2mol的钯-H_2IPr 1五个大气压的一氧化碳以氨气饱和的四氢呋喃作溶剂由不同的有机硼化合物与三种芳基重氮盐的四组份偶联反应同时不仅对生成的多种产物进行了定 L-氮杂环丁烷-2-羧酸L-氮杂环丁烷-2-羧酸又称 S -氮杂环丁烷-2-羧酸简称为L-Aze1955年由Fowden从植物铃兰 Convallaria majalis 中分离得到成为第一个被证实的植物中天然存在的氮杂环丁烷结构作为一种非典型的氨基酸已经发现 S -氮杂环丁烷-2-羧酸可广泛用于对多肽结构的修饰以及诸如不对称的羰基还原Michael 加成环丙烷化和Diels-Alder反应等不对称合成中的多个领域本文通过对 S -氮杂环丁烷-2-羧酸合成路线的研究综述了五种可行的合成路线及方法通过比较选用以L-天冬氨酸为初始原料合成 S -氮杂环丁烷-2-羧酸的路线即通过酯化反应活泼氢保护格氏反应内酰胺化反应还原反应氨基保护氧化反应脱保护等反应来合成 S -氮杂环丁烷-2-羧酸分析了每步反应的机理并对 S -氮杂环丁烷-2-羧酸的应用及前景给予展望通过热分析红外质谱核磁等分析手段对合成的化合物的结构进行表征结果表明所得的产物符合目标产物所合成的化合物的结构性能指标与设计的目标要求一致每步反应的收率都在70%以上可以判定以L-天冬氨酸为初始原料合成 S -氮杂环丁烷的路线方案切实可行。
毕业设计外文文献翻译【范本模板】
毕业设计(论文)外文资料翻译系别:专业:班级:姓名:学号:外文出处:附件: 1. 原文; 2。
译文2013年03月附件一:A Rapidly Deployable Manipulator SystemChristiaan J。
J。
Paredis, H. Benjamin Brown,Pradeep K. KhoslaAbstract:A rapidly deployable manipulator system combines the flexibility of reconfigurable modular hardware with modular programming tools,allowing the user to rapidly create a manipulator which is custom-tailored for a given task. This article describes two main aspects of such a system,namely,the Reconfigurable Modular Manipulator System (RMMS)hardware and the corresponding control software。
1 IntroductionRobot manipulators can be easily reprogrammed to perform different tasks, yet the range of tasks that can be performed by a manipulator is limited by mechanicalstructure。
Forexample,a manipulator well-suited for precise movement across the top of a table would probably no be capable of lifting heavy objects in the vertical direction. Therefore,to perform a given task,one needs to choose a manipulator with an appropriate mechanical structure.We propose the concept of a rapidly deployable manipulator system to address the above mentioned shortcomings of fixed configuration manipulators。
_毕业设计外文文献及翻译_
_毕业设计外文文献及翻译_Graduation Thesis Foreign Literature Review and Chinese Translation1. Title: "The Impact of Artificial Intelligence on Society"Abstract:人工智能对社会的影响摘要:人工智能技术的快速发展引发了关于其对社会影响的讨论。
本文探讨了人工智能正在重塑不同行业(包括医疗保健、交通运输和教育)的各种方式。
还讨论了AI实施的潜在益处和挑战,以及伦理考量。
总体而言,本文旨在提供对人工智能对社会影响的全面概述。
2. Title: "The Future of Work: Automation and Job Displacement"Abstract:With the rise of automation technologies, there is growing concern about the potential displacement of workers in various industries. This paper examines the trends in automation and its impact on jobs, as well as the implications for workforce development and retraining programs. The ethical and social implications of automation are also discussed, along with potential strategies for mitigating job displacement effects.工作的未来:自动化和失业摘要:随着自动化技术的兴起,人们越来越担心各行业工人可能被替代的问题。
毕业设计外文文献及翻译
毕业设计外文文献及翻译毕业设计外文文献及翻译在进行毕业设计时,外文文献的阅读和翻译是一个非常重要的环节。
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通过写作和讨论,我们可以将外文文献的内容转化为自己的知识和理解,为自己的毕业设计提供有力的支持和论证。
总之,毕业设计外文文献的阅读和翻译是一个重要的环节。
通过阅读外文文献,我们可以了解最新的研究进展和学术观点,拓宽自己的知识视野;通过翻译外文文献,我们可以将这些宝贵的资料转化为自己的知识和理解,为自己的毕业设计提供有力的支持。
毕业设计论文外文文献翻译智能交通信号灯控制中英文对照
英语原文Intelligent Traffic Light Controlby Marco Wiering The topic I picked for our community project was traffic lights. In a community, people need stop signs and traffic lights to slow down drivers from going too fast. If there were no traffic lights or stop signs, people’s lives would be in danger from drivers going too fast.The urban traffic trends towards the saturation, the rate of increase of the road of big city far lags behind rate of increase of the car.The urban passenger traffic has already become the main part of city traffic day by day and it has used about 80% of the area of road of center district. With the increase of population and industry activity, people's traffic is more and more frequent, which is unavoidable. What means of transportation people adopt produces pressure completely different to city traffic. According to calculating, if it is 1 to adopt the area of road that the public transport needs, bike needs 5-7, car needs 15-25, even to walk is 3 times more than to take public transits. So only by building road can't solve the city traffic problem finally yet. Every large city of the world increases the traffic policy to the first place of the question.For example,according to calculating, when the automobile owning amount of Shanghai reaches 800,000 (outside cars count separately ), if it distributes still as now for example: center district accounts for great proportion, even when several loop-lines and arterial highways have been built up , the traffic cannot be improved more than before and the situation might be even worse. So the traffic policy Shanghai must adopt , or called traffic strategy is that have priority to develop public passenger traffic of city, narrow the scope of using of the bicycle progressively , control the scale of growth of the car traffic in the center district, limit the development of the motorcycle strictly.There are more municipals project under construction in big city. the influence on the traffic is greater.Municipal infrastructure construction is originally a good thing of alleviating the traffic, but in the course of constructing, it unavoidably influence the local traffic. Some road sections are blocked, some change into an one-way lane, thus the vehicle can only take a devious route . The construction makes the road very narrow, forming the bottleneck, which seriously influence the car flow.When having stop signs and traffic lights, people have a tendency to drive slower andlook out for people walking in the middle of streets. To put a traffic light or a stop sign in a community, it takes a lot of work and planning from the community and the city to put one in. It is not cheap to do it either. The community first needs to take a petition around to everyone in the community and have them sign so they can take it to the board when the next city council meeting is. A couple residents will present it to the board, and they will decide weather or not to put it in or not. If not put in a lot of residents might be mad and bad things could happened to that part of the city.When the planning of putting traffic lights and stop signs, you should look at the subdivision plan and figure out where all the buildings and schools are for the protection of students walking and riding home from school. In our plan that we have made, we will need traffic lights next to the school, so people will look out for the students going home. We will need a stop sign next to the park incase kids run out in the street. This will help the protection of the kids having fun. Will need a traffic light separating the mall and the store. This will be the busiest part of the town with people going to the mall and the store. And finally there will need to be a stop sign at the end of the streets so people don’t drive too fast and get in a big accident. If this is down everyone will be safe driving, walking, or riding their bikes.In putting in a traffic light, it takes a lot of planning and money to complete it. A traffic light cost around $40,000 to $125,000 and sometimes more depending on the location. If a business goes in and a traffic light needs to go in, the business or businesses will have to pay some money to pay for it to make sure everyone is safe going from and to that business. Also if there is too many accidents in one particular place in a city, a traffic light will go in to safe people from getting a severe accident and ending their life and maybe someone else’s.The reason I picked this part of our community development report was that traffic is a very important part of a city. If not for traffic lights and stop signs, people’s lives would be in danger every time they walked out their doors. People will be driving extremely fast and people will be hit just trying to have fun with their friends. So having traffic lights and stop signs this will prevent all this from happening.Traffic in a city is very much affected by traffic light controllers. When waiting for a traffic light, the driver looses time and the car uses fuel. Hence, reducing waiting times before traffic lights can save our European society billions of Euros annually. To make traffic light controllers more intelligent, we exploit the emergence of novel technologies such as communication networks and sensor networks, as well as the use of more sophisticated algorithms for setting traffic lights. Intelligent traffic light control does not only mean thattraffic lights are set in order to minimize waiting times of road users, but also that road users receive information about how to drive through a city in order to minimize their waiting times. This means that we are coping with a complex multi-agent system, where communication and coordination play essential roles. Our research has led to a novel system in which traffic light controllers and the behaviour of car drivers are optimized using machine-learning methods.Our idea of setting a traffic light is as follows. Suppose there are a number of cars with their destination address standing before a crossing. All cars communicate to the traffic light their specific place in the queue and their destination address. Now the traffic light has to decide which option (ie, which lanes are to be put on green) is optimal to minimize the long-term average waiting time until all cars have arrived at their destination address. The learning traffic light controllers solve this problem by estimating how long it would take for a car to arrive at its destination address (for which the car may need to pass many different traffic lights) when currently the light would be put on green, and how long it would take if the light would be put on red. The difference between the waiting time for red and the waiting time for green is the gain for the car. Now the traffic light controllers set the lights in such a way to maximize the average gain of all cars standing before the crossing. To estimate the waiting times, we use 'reinforcement learning' which keeps track of the waiting times of individual cars and uses a smart way to compute the long term average waiting times using dynamic programming algorithms. One nice feature is that the system is very fair; it never lets one car wait for a very long time, since then its gain of setting its own light to green becomes very large, and the optimal decision of the traffic light will set his light to green. Furthermore, since we estimate waiting times before traffic lights until the destination of the road user has been reached, the road user can use this information to choose to which next traffic light to go, thereby improving its driving behaviour through a city. Note that we solve the traffic light control problem by using a distributed multi-agent system, where cooperation and coordination are done by communication, learning, and voting mechanisms. To allow for green waves during extremely busy situations, we combine our algorithm with a special bucket algorithm which propagates gains from one traffic light to the next one, inducing stronger voting on the next traffic controller option.We have implemented the 'Green Light District', a traffic simulator in Java in which infrastructures can be edited easily by using the mouse, and different levels of road usage can be simulated. A large number of fixed and learning traffic light controllers have already been tested in the simulator and the resulting average waiting times of cars have been plotted and compared. The results indicate that the learning controllers can reduce average waiting timeswith at least 10% in semi-busy traffic situations, and even much more when high congestion of the traffic occurs.We are currently studying the behaviour of the learning traffic light controllers on many different infrastructures in our simulator. We are also planning to cooperate with other institutes and companies in the Netherlands to apply our system to real world traffic situations. For this, modern technologies such as communicating networks can be brought to use on a very large scale, making the necessary communication between road users and traffic lights possible.中文翻译:智能交通信号灯控制马克·威宁我所选择的社区项目主题是交通灯。
机械设计制造及其自动化毕业论文中英文资料外文翻译
机械设计创造及其自动化毕业论文外文文献翻译INTEGRATION OF MACHINERY译文题目专业机械设计创造及其自动化外文资料翻译INTEGRATION OF MACHINERY(From ELECTRICAL AND MACHINERY INDUSTRY)ABSTRACTMachinery was the modern science and technology development inevitable result, this article has summarized the integration of machinery technology basic outline and the development background .Summarized the domestic and foreign integration of machinery technology present situation, has analyzed the integration of machinery technology trend of development.Key word: integration of machinery ,technology, present situation ,product t,echnique of manufacture ,trend of development0. Introduction modern science and technology unceasing development, impelled different discipline intersecting enormously with the seepage, has caused the project domain technological revolution and the transformation .In mechanical engineering domain, because the microelectronic technology and the computer technology rapid development and forms to the mechanical industry seepage the integration of machinery, caused the mechanical industry the technical structure, the product organization, the function and the constitution, the production method and the management systemof by machinery for the characteristic integration ofdevelopment phase.1. Integration of machinery outline integration of machinery is refers in the organization new owner function, the power function, in the information processing function and the control function introduces the electronic technology, unifies the system the mechanism and the computerization design and the software which constitutes always to call. The integration of machinery development also has become one to have until now own system new discipline, not only develops along with the science and technology, but also entrusts with the new content .But its basic characteristic may summarize is: The integration of machinery is embarks from the system viewpoint, synthesis community technologies and so on utilization mechanical technology, microelectronic technology, automatic control technology, computer technology, information technology, sensing observation and control technology, electric power electronic technology, connection technology, information conversion technology as well as software programming technology, according to the system function goal and the optimized organization goal, reasonable disposition and the layout various functions unit, in multi-purpose, high grade, redundant reliable, in the low energy consumption significance realize the specific function value, and causes the overall system optimization the systems engineering technology .From this produces functional system, then becomes an integration of machinery systematic or the integration of machinery product. Therefore, of coveringtechnology is based on the above community technology organic fusion one kind of comprehensive technology, but is not mechanical technical, the microelectronic technology as well as other new technical simple combination, pieces together .This is the integration of machinery and the machinery adds the machinery electrification which the electricity forms in the concept basic difference .The mechanical engineering technology has the merely technical to develop the machinery electrification, still was the traditional machinery, its main function still was replaces with the enlargement physical strength .But after develops the integration of machinery, micro electron installment besides may substitute for certain mechanical parts the original function, but also can entrust with many new functions,like the automatic detection, the automatic reduction information, demonstrate the record, the automatic control and the control automatic diagnosis and the protection automatically and so on .Not only namely the integration of machinery product is human's hand and body extending, human's sense organ and the brains look, has the intellectualized characteristic is the integration of machinery and the machinery electrification distinguishes in the function essence.2. Integration of machinery development condition integration of machinery development may divide into 3 stages roughly.20th century 60's before for the first stage, this stage is called the initial stage .In this time, the people determination not on own initiative uses the electronic technology the preliminary achievement to consummate the mechanical product the performance .Specially in Second World War period, the war has stimulated the mechanical product and the electronic technology union, these mechanical and electrical union military technology, postwar transfers civilly, to postwar economical restoration positive function .Developed and the development at that time generally speaking also is at the spontaneouscondition .Because at that time the electronic technology development not yet achieved certain level, mechanical technical and electronic technology union also not impossible widespread and thorough development, already developed the product was also unable to promote massively. The 20th century 70~80 ages for the second stage, may be called the vigorous development stage .This time, the computer technology, the control technology, the communication development, has laid the technology base for the integration of machinery development . Large-scale, ultra large scale integrated circuit and microcomputer swift and violent development, has provided the full material base for the integration of machinery development .This time characteristic is :①A mechatronics word first generally is accepted in Japan, probably obtains the quite widespread acknowledgment to 1980s last stages in the worldwide scale ;②The integration of machinery technology and the product obtained the enormous development ;③The various countries start to the integration of machinery technology and the product give the very big attention and the support. 1990s later periods, started the integration of machinery technology the new stagewhich makes great strides forward to the intellectualized direction, the integration of machinery enters the thorough development time .At the same time, optics, the communication and so on entered the integration of machinery, processes the technology also zhan to appear tiny in the integration of machinery the foot, appeared the light integration of machinery and the micro integration of machinery and so on the new branch; On the other hand to the integration of machinery system modeling design, the analysis and the integrated method, the integration of machinery discipline system and the trend of development has all conducted the thorough research .At the same time, because the hugeprogress which domains and so on artificial intelligence technology, neural network technology and optical fiber technology obtain, opened the development vast world for the integration of machinery technology .These research, will urge the integration of machinery further to establish the integrity the foundation and forms the integrity gradually the scientific system. Our country is only then starts from the beginning of 1980s in this aspect to study with the application .The State Councilsummary had considered fully on international the influence which and possibly brought from this about the integration of machinery technology developmenttrend .Many universities, colleges and institutes, the development facility and some large and middle scale enterprises have done the massive work to this technical development and the application, does not yield certain result, but and so on the advanced countries compared with Japan still has the suitable disparity.3. Integration of machinery trend of development integrations of machinery are the collection machinery, the electron, optics, the control, the computer, the information and so on the multi-disciplinary overlapping syntheses, its development and the progress rely on and promote the correlation technology development and the progress .Therefore, the integration of machinery main development direction is as follows:3.1 Intellectualized intellectualizations are 21st century integration of machinery technological development important development directions .Theartificial intelligence obtains day by day in the integration of machinery constructor's research takes, the robot and the numerical control engine bedis to the machine behavior description, is in the control theory foundation, the absorption artificial intelligence, the operations research, the computer science, the fuzzy mathematics, the psychology, the physiology and the chaos dynamics and so on the new thought, the new method, simulate the human intelligence, enable it to have abilities and so on judgment inference, logical thinking, independent decision-making, obtains the higher control goal in order to .Indeed, enable the integration of machinery product to have with the human identical intelligence, is not impossible, also is nonessential .But, the high performance, the high speed microprocessor enable the integration of machinery product to have preliminary intelligent or human's partial intelligences, then is completely possible and essential.In the modern manufacture process, the information has become the control manufacture industry the determining factor, moreover is the most active actuation factor .Enhances the manufacture system information-handling capacity to become the modern manufacture science development a key point .As a result of the manufacture system information organization and structure multi-level, makes the information the gain, the integration and the fusion presents draws up the character, information measure multi-dimensional, as well as information organization's multi-level .In the manufacture information structural model, manufacture information uniform restraint, dissemination processing and magnanimous data aspects and so on manufacture knowledge library management, all also wait for further break through.Each kind of artificial intelligence tool and the computation intelligence method promoted the manufacture intelligence development in the manufacture widespread application .A kind based on the biological evolution algorithm computation intelligent agent, in includes thescheduling problem in the combination optimization solution area of technology, receives the more and more universal attention, hopefully completes the combination optimization question when the manufacture the solution speed and the solution precision aspect breaks through the question scale in pairs the restriction .The manufacture intelligence also displays in: The intelligent dispatch, the intelligent design, the intelligent processing, the robot study, the intelligent control, the intelligent craft plan, the intelligent diagnosis and so on are various These question key breakthrough, may form the product innovation the basic research system. Between 2 modern mechanical engineering front science different science overlapping fusion will have the new science accumulation, the economical development and society's progress has had the new request and the expectation to the science and technology, thus will form the front science .The front science also has solved and between the solution scientific question border area .The front science has the obvious time domain, the domain and the dynamic characteristic .The project front science distinguished in the general basic science important characteristic is it has covered the key science and technology question which the project actual appeared.Manufacture system is a complex large-scale system, for satisfies the manufacture system agility, the fast response and fast reorganization ability, must profit from the information science, the life sciences and the social sciences and so on the multi-disciplinary research results, the exploration manufacture system new architecture, the manufacture pattern and the manufacture system effective operational mechanism .Makes the system optimization the organizational structure and the good movement condition is makes the system modeling , the simulation and the optimized essential target .Not only the manufacture system new architecture to makes the enterprise the agility and may reorganize ability to the demand response ability to have the vital significance, moreover to made the enterprise first floor production equipment the flexibility and may dynamic reorganization ability set a higher request .The biological manufacture view more and more many is introduced the manufacture system, satisfies the manufacture system new request.The study organizes and circulates method and technique of complicated system from the biological phenomenon, is a valid exit which will solve many hard nut to cracks that manufacturing industry face from now on currently .Imitating to living what manufacturing point is mimicry living creature organ of from the organization, from match more, from growth with from evolution etc. function structure and circulate mode of a kind of manufacturing system and manufacturing process.The manufacturing drives in the mechanism under, continuously by one's own perfect raise on organizing structure and circulating mode and thus to adapt the process of[with] ability for the environment .For from descend but the last product proceed together a design and make a craft rules the auto of the distance born, produce system of dynamic state reorganization and product and manufacturing the system tend automatically excellent provided theories foundation and carry out acondition .Imitate to living a manufacturing to belong to manufacturing science and life science of"the far good luck is miscellaneous to hand over", it will produce to the manufacturing industry for 21 centuries huge of influence .机电一体化摘要机电一体化是现代科学技术发展的必然结果,本文简述了机电一体化技术的基本概要和发展背景。
马铃薯去皮结构设计毕业课程设计外文文献翻译、中英文翻译
1 英文文献翻译1.1 英文文献原文题目Potatoes Potatoes peeled peeled peeled structure structure structure design designAbstract: Abstract: the the the graduation graduation graduation design design design is is is mainly mainly mainly studied studied studied on on on the the the bas bas is is of of of the the the principle principle principle of of of friction friction friction of of of potato potato potato peeling peeling peeling machine machine machine d d esign, esign, working working working principle principle principle and and and the the the composition composition composition of of of the the the equipment equipment . . Through Through Through the the the analysis analysis analysis of of of original original original data, data, data, project project project demonstratio demonstratio n n and and and related related related data data data analysis analysis analysis and and and calculation, calculation, calculation, the the the overall overall overall des des ign ign of of of a a a complete complete complete potato potato potato peeler peeler peeler to to to peel peel peel and and and mechanical mechanical mechanical stru stru cture cture is is is a a a new new new form, form, form, to to to better better better serve serve serve the the the fruits fruits fruits and and and vegeta vegeta bles bles to to to the the the development development development of of of leather leather leather industry, industry, industry, better better better adapt adapt adapt to to the the demand demand demand of of of the the the market market market both both both at at at home home home and and and abroad, abroad, abroad, so so so has has the the good good good market market market prospect. prospect.Keywords: Keywords: potatoes potatoes potatoes peeled peeled peeled structure; structure; structure; Friction Friction Friction ; ; ; drive drive 1 1 the the the domestic domestic domestic research research research status statusTechnology Technology is is is to to to measure measure measure whether whether whether an an an enterprise enterprise enterprise has has has the the the advan advan ced ced nature, nature, nature, whether whether whether have have have market market market competitiveness, competitiveness, competitiveness, whether whether whether can can keep keep ahead ahead ahead of of of competitors' competitors' competitors' important important important index. index. index. With With With the the the rapid rapid rapid d d evelopment evelopment of of of domestic domestic domestic potato potato potato peeling peeling peeling agency agency agency market, market, market, the the the core core of of the the the related related related production production production technology technology technology and and and research research research and and and devel devel opment opment will will will certainly certainly certainly has has has become become become the the the focus focus focus of of of the the the industry industry enterprises. enterprises. Understand Understand Understand the the the potato potato potato peeling peeling peeling machine machine machine in in in the the the pro pro duction duction of of of the the the core core core technology technology technology research research research and and and development development development at at at h h ome ome and and and abroad, abroad, abroad, process process process equipment, equipment, equipment, technology, technology, technology, application application application and and trend, trend, for for for an an an enterprise enterprise enterprise to to to improve improve improve product product product technical technical technical speci speci fication, fication, improve improve improve the the the market market market competitiveness competitiveness competitiveness is is is critical. critical. Potato Potato products products products the the the main main main varieties varieties varieties of of of potatoes, potatoes, potatoes, potato potato potato chips,chips, dehydrated dehydrated mashed mashed mashed potatoes, potatoes, potatoes, etc. etc. etc. No No No matter matter matter what what what kind kind kind of of of pr products, oducts, its its its processing processing processing technology technology technology requirements requirements requirements of of of raw raw raw material material s s to to to deal deal deal with with with the the the peel peel peel potatoes, potatoes, potatoes, to to to guarantee guarantee guarantee the the the quality quality of of the the the products, products, products, ensure ensure ensure its its its appearance, appearance, appearance, color color color and and and taste. taste. taste. P P eel eel potatoes potatoes potatoes peeled peeled peeled methods methods methods mainly mainly mainly include include include artificial, artificial, artificial, chemica chemica l l peeling, peeling, peeling, mechanical mechanical mechanical peeling, peeling, peeling, etc. etc. etc. Artificial Artificial Artificial to to to skin skin skin peelin peelin g g effect effect effect is is is better, better, better, but but but low low low efficiency, efficiency, efficiency, high high high loss loss loss rate, rate, rate, obv obv iously iously can can can not not not adapt adapt adapt to to to the the the needs needs needs of of of the the the development development development of of of th th e e potato potato potato industrialization; industrialization; industrialization; Chemical Chemical Chemical peeling peeling peeling a a a hot hot hot alkaline alkaline alkaline o o r r peel peel peel and and and low low low temperature temperature temperature liquid liquid liquid method method method in in in two two two forms, forms, forms, main main ly ly rely rely rely on on on the the the strong strong strong alkali alkali alkali solution solution solution and and and liquid liquid liquid chemical chemical chemical p p eeling eeling effect, effect, effect, softening softening softening and and and relaxation relaxation relaxation potato potato potato skins skins skins and and and body body -to -to keep, keep, keep, then then then use use use high high high pressure pressure pressure water water water jet, jet, jet, peeled. peeled. peeled. This This This me me thod thod the the the flushing flushing flushing process process process of of of before before before and and and after after after peeling peeling peeling the the the d d emand emand is is is higher, higher, higher, and and and liquid liquid liquid alkali, alkali, alkali, peel peel peel or or or consumption consumption consumption is is too too large, large, large, the the the cost cost cost is is is higher, higher, higher, and and and this this this way way way the the the serious serious serious in in fluence fluence the the the taste taste taste of of of the the the product. product. product. Mechanical Mechanical Mechanical peeling peeling peeling is is is fric fric tion tion peel peel peel form, form, form, the the the main main main dependence dependence dependence between between between potato potato potato and and and potat potat o o and and and potato potato potato with with with silicon silicon silicon carbide carbide carbide or or or rubber rubber rubber friction friction friction between between role role and and and achieve achieve achieve the the the goal goal goal of of of peel, peel, peel, good good good effect effect effect of of of this this this a a pproach pproach to to to skin, skin, skin, reduce reduce reduce the the the production production production cost, cost, cost, reduced reduced reduced environm environm entalpollution, pollution, simple simple simple operation, operation, operation, fast fast fast speed, speed, speed, can can can one one one person person person opera opera tion, tion, high high high energy energy energy efficiency efficiency efficiency to to to maximize maximize maximize the the the interests interests interests of of of th th e e products. products.2. 2. the the the working working working principle principle principle of of of the the the potato potato potato peeler peelerThe The potato potato potato peeling peeling peeling machine machine machine adopts adopts adopts horizontal horizontal horizontal machine, machine, machine, mainly mainly including including working working working cylinder, cylinder, cylinder, work work work table, table, table, frame frame frame and and and transmission transmission parts parts (see (see (see diagram). diagram). diagram). When When When to to to work work work in in in the the the potato potato potato peeling peeling peeling m m achine, achine, wheel wheel wheel rotation, rotation, rotation, the the the material material material by by by a a a bucket bucket bucket shape shape shape inlet inlet, , material material material fall fall fall on on on the the the surface surface surface of of of a a a rotating rotating rotating brush brush brush roller roller corrugated corrugated bulge, bulge, bulge, the the the effect effect effect of of of the the the centrifugal centrifugal centrifugal force force force by by by the the brush brush roller roller roller tangent tangent tangent upward upward upward movement, movement, movement, material material material constant constant constant alon alon g g the the the motion motion motion for for for a a a cylindrical cylindrical cylindrical wall, wall, wall, rise rise rise to to to the the the top, top, top, was was at at the the the top top top of of of the the the block block block back back back into into into the the the working working working surface surface surface of of the the plate. plate. plate. Into Into Into the the the rough rough rough surface surface surface and and and friction friction friction brush brush brush roll.roll. The The reciprocating reciprocating reciprocating movement movement movement of of of the the the material material material in in in this this this process,process, by by violent violent violent agitation, agitation, agitation, and and and formed formed formed with with with a a a brush brush brush roller, roller, roller, wall wall and and between between between particles particles particles is is is given given given priority priority priority to to to with with with flip, flip, flip, rubb rubb ing ing friction, friction, friction, impact impact impact of of of comprehensive comprehensive comprehensive mechanical mechanical mechanical effects, effects, effects, so so as as to to to achieve achieve achieve the the the aim aim aim of of of the the the skin. skin. skin. At At At the the the same same same time time time of of of f f riction riction peel, peel, peel, from from from inject inject inject water water water into into into the the the hole, hole, hole, in in in a a a timely timely manner manner will will will be be be wiped wiped wiped off off off the the the skin skin skin of of of the the the through through through brush brush brush b b rush rush roll roll roll and and and roll roll roll gap gap gap to to to discharge discharge discharge mouth mouth mouth eduction eduction eduction body. body. body. In In the the case case case of of of non-stop, non-stop, non-stop, open open open the the the discharge discharge discharge valve valve valve of of of mouth, mouth, material material by by by dial dial dial discharged discharged discharged through through through the the the discharge discharge discharge port. port. port. After After peeling peeling potatoes potatoes potatoes peel peel peel by by by institutions institutions institutions discharging discharging discharging chute chute chute into into the the auxiliary auxiliary auxiliary body, body, body, after after after screening screening screening and and and other other other auxiliary auxiliary auxiliary wor wor k k again again again into into into the the the next next next procedure. procedure.3. 3. summary summaryBelieve Believe in in in the the the near near near future, future, future, once once once the the the product product product is is is applied applied applied to to the the actual, actual, actual, will will will greatly greatly greatly save save save the the the working working working time, time, time, improve improve improve wo wo rk rk efficiency, efficiency, efficiency, improve improve improve the the the economic economic economic benefit, benefit, benefit, at at at the the the same same same tim tim e e will will will make make make a a a great great great contribution contribution contribution for for for the the the mass mass mass production, production, production, g g iving iving impetus impetus impetus to to to the the the development development development of of of potato potato potato industry industry industry better better better a a nd nd faster. faster. faster. Mechanical Mechanical Mechanical peeling, peeling, peeling, powered powered powered by by by motor, motor, motor, through through through the the pulley pulley drive drive drive cylinder cylinder cylinder at at at the the the bottom bottom bottom of of of the the the spinning spinning spinning l. Low Low middle, middle, middle, high high high edge edge edge mill mill mill wheel wheel wheel surface, surface, surface, undulate. undulate. undulate. Tubers Tubers to to join join join the the the cylinder, cylinder, cylinder, each each each other other other due due due to to to centrifugal centrifugal centrifugal force forceand and the the the friction friction friction effect, effect, effect, within within within the the the cylinder cylinder cylinder up, up, up, down, down, down, lef lef t, t, right right right turn, turn, turn, and and and constantly constantly constantly rolling; rolling; rolling; And And And the the the rubber rubber rubber cylind cylind er er lining, lining, lining, will will will rebound rebound rebound tuber, tuber, tuber, in in in the the the mill mill mill and and and the the the cylinder cylinder wall wall under under under the the the function function function of of of rubber rubber rubber potato potato potato tuber tuber tuber is is is grinding grinding to to the the the skin skin skin evenly, evenly, evenly, achieve achieve achieve the the the goal goal goal of of of potato potato potato peeling. peeling. peeling. T T o o skin skin skin with with with clear clear clear water, water, water, and and and then then then open open open the the the side side side door, door, door, tube tube r r discharge discharge discharge from from from a a a side side side door, door, door, dander dander dander with with with flow flow flow from from from the the the di di scharge scharge gap gap gap around around around the the the millstone. millstone. millstone. The The The machine machine machine for for for batch batch batch prod prod uction, uction, peeling peeling peeling machine, machine, machine, mill mill mill rotate rotate rotate at at at a a a certain certain certain speed, speed, speed, rol rol ler ler potato potato potato in in in under under under the the the action action action of of of centrifugal centrifugal centrifugal force, force, force, gravity gravity and and the the the friction, friction, friction, using using using potato potato potato work work work relative relative relative to to to the the the mill,mill, the the relative relative relative speed speed speed difference difference difference between between between the the the potato potato potato skin skin skin remov remov ed.1.2中文翻译马铃薯去皮结构设计马铃薯去皮结构设计摘要摘要::本次毕业设计主要研究了以摩擦原理为基础的马铃薯去皮机的设计要点、工作原理工作原理 及设备的组成。
建筑设计毕业论文中英文资料外文翻译文献
毕业论文中英文资料外文翻译文献Architecture StructureWe have and the architects must deal with the spatial aspect of activity, physical, and symbolic needs in such a way that overall performance integrity is assured. Hence, he or she well wants to think of evolving a building environment as a total system of interacting and space forming subsystems. Is represents a complex challenge, and to meet it the architect will need a hierarchic design process that provides at least three levels of feedback thinking: schematic, preliminary, and final.Such a hierarchy is necessary if he or she is to avoid being confused , at conceptual stages of design thinking ,by the myriad detail issues that can distract attention from more basic consideration s .In fact , we can say that an architect’s ability to distinguish the more basic form the more detailed issues is essential to his success as a designer .The object of the schematic feed back level is to generate and evaluate overall site-plan, activity-interaction, and building-configuration options .To do so the architect must be able to focus on the interaction of the basic attributes of the site context, the spatial organization, and the symbolism as determinants of physical form. This means that ,in schematic terms ,the architect may first conceive and model a building design as an organizational abstraction of essential performance-space in teractions.Then he or she may explore the overall space-form implications of the abstraction. As an actual building configuration option begins to emerge, it will be modified to include consideration for basic site conditions.At the schematic stage, it would also be helpful if the designer could visualize his or her options for achieving overall structural integrity and consider the constructive feasibility and economic of his or her scheme .But this will require that the architect and/or a consultant be able to conceptualize total-system structural options in terms of elemental detail .Such overall thinking can be easily fed back to improve the space-form scheme.At the preliminary level, the architect’s emphasis will shift to the elaboration of his or her more promising schematic design options .Here the architect’s structural needs will shift toapproximate design of specific subsystem options. At this stage the total structural scheme is developed to a middle level of specificity by focusing on identification and design of major subsystems to the extent that their key geometric, component, and interactive properties are established .Basic subsystem interaction and design conflicts can thus be identified and resolved in the context of total-system objectives. Consultants can play a significant part in this effort; these preliminary-level decisions may also result in feedback that calls for refinement or even major change in schematic concepts.When the designer and the client are satisfied with the feasibility of a design proposal at the preliminary level, it means that the basic problems of overall design are solved and details are not likely to produce major change .The focus shifts again ,and the design process moves into the final level .At this stage the emphasis will be on the detailed development of all subsystem specifics . Here the role of specialists from various fields, including structural engineering, is much larger, since all detail of the preliminary design must be worked out. Decisions made at this level may produce feedback into Level II that will result in changes. However, if Levels I and II are handled with insight, the relationship between the overall decisions, made at the schematic and preliminary levels, and the specifics of the final level should be such that gross redesign is not in question, Rather, the entire process should be one of moving in an evolutionary fashion from creation and refinement (or modification) of the more general properties of a total-system design concept, to the fleshing out of requisite elements and details.To summarize: At Level I, the architect must first establish, in conceptual terms, the overall space-form feasibility of basic schematic options. At this stage, collaboration with specialists can be helpful, but only if in the form of overall thinking. At Level II, the architect must be able to identify the major subsystem requirements implied by the scheme and substantial their interactive feasibility by approximating key component properties .That is, the properties of major subsystems need be worked out only in sufficient depth to very the inherent compatibility of their basic form-related and behavioral interaction . This will mean a somewhat more specific form of collaboration with specialists then that in level I .At level III ,the architect and the specific form of collaboration with specialists then that providing for all of the elemental design specifics required to produce biddable construction documents .Of course this success comes from the development of the Structural Material.1.Reinforced ConcretePlain concrete is formed from a hardened mixture of cement ,water ,fine aggregate, coarse aggregate (crushed stone or gravel),air, and often other admixtures. The plastic mix is placed and consolidated in the formwork, then cured to facilitate the acceleration of the chemical hydration reaction lf the cement/water mix, resulting in hardened concrete. The finished product has high compressive strength, and low resistance to tension, such that its tensile strength is approximately one tenth lf its compressive strength. Consequently, tensile and shear reinforcement in the tensile regions of sections has to be provided to compensate for the weak tension regions in the reinforced concrete element.It is this deviation in the composition of a reinforces concrete section from the homogeneity of standard wood or steel sections that requires a modified approach to the basic principles of structural design. The two components of the heterogeneous reinforced concrete section are to be so arranged and proportioned that optimal use is made of the materials involved. This is possible because concrete can easily be given any desired shape by placing and compacting the wet mixture of the constituent ingredients are properly proportioned, the finished product becomes strong, durable, and, in combination with the reinforcing bars, adaptable for use as main members of any structural system.The techniques necessary for placing concrete depend on the type of member to be cast: that is, whether it is a column, a bean, a wall, a slab, a foundation. a mass columns, or an extension of previously placed and hardened concrete. For beams, columns, and walls, the forms should be well oiled after cleaning them, and the reinforcement should be cleared of rust and other harmful materials. In foundations, the earth should be compacted and thoroughly moistened to about 6 in. in depth to avoid absorption of the moisture present in the wet concrete. Concrete should always be placed in horizontal layers which are compacted by means of high frequency power-driven vibrators of either the immersion or external type, as the case requires, unless it is placed by pumping. It must be kept in mind, however, that over vibration can be harmful since it could cause segregation of the aggregate and bleeding of the concrete.Hydration of the cement takes place in the presence of moisture at temperatures above 50°F. It is necessary to maintain such a condition in order that the chemical hydration reaction can take place. If drying is too rapid, surface cracking takes place. This would result in reduction of concrete strength due to cracking as well as the failure to attain full chemical hydration.It is clear that a large number of parameters have to be dealt with in proportioning a reinforced concrete element, such as geometrical width, depth, area of reinforcement, steel strain, concrete strain, steel stress, and so on. Consequently, trial and adjustment is necessary in the choice ofconcrete sections, with assumptions based on conditions at site, availability of the constituent materials, particular demands of the owners, architectural and headroom requirements, the applicable codes, and environmental reinforced concrete is often a site-constructed composite, in contrast to the standard mill-fabricated beam and column sections in steel structures.A trial section has to be chosen for each critical location in a structural system. The trial section has to be analyzed to determine if its nominal resisting strength is adequate to carry the applied factored load. Since more than one trial is often necessary to arrive at the required section, the first design input step generates into a series of trial-and-adjustment analyses.The trial-and –adjustment procedures for the choice of a concrete section lead to the convergence of analysis and design. Hence every design is an analysis once a trial section is chosen. The availability of handbooks, charts, and personal computers and programs supports this approach as a more efficient, compact, and speedy instructional method compared with the traditional approach of treating the analysis of reinforced concrete separately from pure design.2. EarthworkBecause earthmoving methods and costs change more quickly than those in any other branch of civil engineering, this is a field where there are real opportunities for the enthusiast. In 1935 most of the methods now in use for carrying and excavating earth with rubber-tyred equipment did not exist. Most earth was moved by narrow rail track, now relatively rare, and the main methods of excavation, with face shovel, backacter, or dragline or grab, though they are still widely used are only a few of the many current methods. To keep his knowledge of earthmoving equipment up to date an engineer must therefore spend tine studying modern machines. Generally the only reliable up-to-date information on excavators, loaders and transport is obtainable from the makers.Earthworks or earthmoving means cutting into ground where its surface is too high ( cuts ), and dumping the earth in other places where the surface is too low ( fills). Toreduce earthwork costs, the volume of the fills should be equal to the volume of the cuts and wherever possible the cuts should be placednear to fills of equal volume so as to reduce transport and double handlingof the fill. This work of earthwork design falls on the engineer who lays out the road since it is the layout of the earthwork more than anything else which decides its cheapness. From the available maps ahd levels, the engineering must try to reach as many decisions as possible in the drawing office by drawing cross sections of the earthwork. On the site when further information becomes available he can make changes in jis sections and layout,but the drawing lffice work will not have been lost. It will have helped him to reach the best solution in the shortest time.The cheapest way of moving earth is to take it directly out of the cut and drop it as fill with the same machine. This is not always possible, but when it canbe done it is ideal, being both quick and cheap. Draglines, bulldozers and face shovels an do this. The largest radius is obtained with thedragline,and the largest tonnage of earth is moved by the bulldozer, though only over short distances.The disadvantages of the dragline are that it must dig below itself, it cannot dig with force into compacted material, it cannot dig on steep slopws, and its dumping and digging are not accurate.Face shovels are between bulldozers and draglines, having a larger radius of action than bulldozers but less than draglines. They are anle to dig into a vertical cliff face in a way which would be dangerous tor a bulldozer operator and impossible for a dragline. Each piece of equipment should be level of their tracks and for deep digs in compact material a backacter is most useful, but its dumping radius is considerably less than that of the same escavator fitted with a face shovel.Rubber-tyred bowl scrapers are indispensable for fairly level digging where the distance of transport is too much tor a dragline or face shovel. They can dig the material deeply ( but only below themselves ) to a fairly flat surface, carry it hundreds of meters if need be, then drop it and level it roughly during the dumping. For hard digging it is often found economical to keep a pusher tractor ( wheeled or tracked ) on the digging site, to push each scraper as it returns to dig. As soon as the scraper is full,the pusher tractor returns to the beginning of the dig to heop to help the nest scraper.Bowl scrapers are often extremely powerful machines;many makers build scrapers of 8 cubic meters struck capacity, which carry 10 m ³ heaped. The largest self-propelled scrapers are of 19 m ³struck capacity ( 25 m ³ heaped )and they are driven by a tractor engine of 430 horse-powers.Dumpers are probably the commonest rubber-tyred transport since they can also conveniently be used for carrying concrete or other building materials. Dumpers have the earth container over the front axle on large rubber-tyred wheels, and the container tips forwards on most types, though in articulated dumpers the direction of tip can be widely varied. The smallest dumpers have a capacity of about 0.5 m ³, and the largest standard types are of about 4.5 m ³. Special types include the self-loading dumper of up to 4 m ³ and the articulated type of about 0.5 m ³. The distinction between dumpers and dump trucks must be remembered .dumpers tip forwards and the driver sits behind the load. Dump trucks are heavy, strengthened tipping lorries, the driver travels in front lf the load and the load is dumped behind him, so they are sometimes called rear-dump trucks.3.Safety of StructuresThe principal scope of specifications is to provide general principles and computational methods in order to verify safety of structures. The “ safety factor ”, which according to modern trends is independent of the nature and combination of the materials used, can usually be defined as the ratio between the conditions. This ratio is also proportional to the inverse of the probability ( risk ) of failure of the structure.Failure has to be considered not only as overall collapse of the structure but also asunserviceability or, according to a more precise. Common definition. As the reaching of a “ limit state ” which causes the construction not to accomplish the task it was designed for. Ther e are two categories of limit state :(1)Ultimate limit sate, which corresponds to the highest value of the load-bearing capacity. Examples include local buckling or global instability of the structure; failure of some sections and subsequent transformation of the structure into a mechanism; failure by fatigue; elastic or plastic deformation or creep that cause a substantial change of the geometry of the structure; and sensitivity of the structure to alternating loads, to fire and to explosions.(2)Service limit states, which are functions of the use and durability of the structure. Examples include excessive deformations and displacements without instability; early or excessive cracks; large vibrations; and corrosion.Computational methods used to verify structures with respect to the different safety conditions can be separated into:(1)Deterministic methods, in which the main parameters are considered as nonrandom parameters.(2)Probabilistic methods, in which the main parameters are considered as random parameters.Alternatively, with respect to the different use of factors of safety, computational methods can be separated into:(1)Allowable stress method, in which the stresses computed under maximum loads are compared with the strength of the material reduced by given safety factors.(2)Limit states method, in which the structure may be proportioned on the basis of its maximum strength. This strength, as determined by rational analysis, shall not be less than that required to support a factored load equal to the sum of the factored live load and dead load ( ultimate state ).The stresses corresponding to working ( service ) conditions with unfactored live and dead loads are compared with prescribed values ( service limit state ) . From the four possible combinations of the first two and second two methods, we can obtain some useful computational methods. Generally, two combinations prevail:(1)deterministic methods, which make use of allowable stresses.(2)Probabilistic methods, which make use of limit states.The main advantage of probabilistic approaches is that, at least in theory, it is possible to scientifically take into account all random factors of safety, which are then combined to define the safety factor. probabilistic approaches depend upon :(1) Random distribution of strength of materials with respect to the conditions of fabrication and erection ( scatter of the values of mechanical properties through out the structure );(2) Uncertainty of the geometry of the cross-section sand of the structure ( faults andimperfections due to fabrication and erection of the structure );(3) Uncertainty of the predicted live loads and dead loads acting on the structure;(4)Uncertainty related to the approximation of the computational method used ( deviation of the actual stresses from computed stresses ).Furthermore, probabilistic theories mean that the allowable risk can be based on several factors, such as :(1) Importance of the construction and gravity of the damage by its failure;(2)Number of human lives which can be threatened by this failure;(3)Possibility and/or likelihood of repairing the structure;(4) Predicted life of the structure.All these factors are related to economic and social considerations such as:(1) Initial cost of the construction;(2) Amortization funds for the duration of the construction;(3) Cost of physical and material damage due to the failure of the construction;(4) Adverse impact on society;(5) Moral and psychological views.The definition of all these parameters, for a given safety factor, allows construction at the optimum cost. However, the difficulty of carrying out a complete probabilistic analysis has to be taken into account. For such an analysis the laws of the distribution of the live load and its induced stresses, of the scatter of mechanical properties of materials, and of the geometry of the cross-sections and the structure have to be known. Furthermore, it is difficult to interpret the interaction between the law of distribution of strength and that of stresses because both depend upon the nature of the material, on the cross-sections and upon the load acting on the structure. These practical difficulties can be overcome in two ways. The first is to apply different safety factors to the material and to the loads, without necessarily adopting the probabilistic criterion. The second is an approximate probabilistic method which introduces some simplifying assumptions ( semi-probabilistic methods ) .文献翻译建筑师必须从一种全局的角度出发去处理建筑设计中应该考虑到的实用活动,物质及象征性的需求。
毕业设计外文文献翻译
毕业设计外文文献翻译Graduation Design Foreign Literature Translation (700 words) Title: The Impact of Artificial Intelligence on the Job Market Introduction:Artificial Intelligence (AI) is a rapidly growing field that has the potential to revolutionize various industries and job markets. With advancements in technologies such as machine learning and natural language processing, AI has become capable of performing tasks traditionally done by humans. This has raised concerns about the future of jobs and the impact AI will have on the job market. This literature review aims to explore the implications of AI on employment and job opportunities.AI in the Workplace:AI technologies are increasingly being integrated into the workplace, with the aim of automating routine and repetitive tasks. For example, automated chatbots are being used to handle customer service queries, while machine learning algorithms are being employed to analyze large data sets. This has resulted in increased efficiency and productivity in many industries. However, it has also led to concerns about job displacement and unemployment.Job Displacement:The rise of AI has raised concerns about job displacement, as AI technologies are becoming increasingly capable of performing tasks previously done by humans. For example, automated machines can now perform complex surgeries with greaterprecision than human surgeons. This has led to fears that certain jobs will become obsolete, leading to unemployment for those who were previously employed in these industries.New Job Opportunities:While AI might potentially replace certain jobs, it also creates new job opportunities. As AI technologies continue to evolve, there will be a greater demand for individuals with technical skills in AI development and programming. Additionally, jobs that require human interaction and emotional intelligence, such as social work or counseling, may become even more in demand, as they cannot be easily automated.Job Transformation:Another potential impact of AI on the job market is job transformation. AI technologies can augment human abilities rather than replacing them entirely. For example, AI-powered tools can assist professionals in making decisions, augmenting their expertise and productivity. This may result in changes in job roles and the need for individuals to adapt their skills to work alongside AI technologies.Conclusion:The impact of AI on the job market is still being studied and debated. While AI has the potential to automate certain tasks and potentially lead to job displacement, it also presents opportunities for new jobs and job transformation. It is essential for individuals and organizations to adapt and acquire the necessary skills to navigate these changes in order to stay competitive in the evolvingjob market. Further research is needed to fully understand the implications of AI on employment and job opportunities.。
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中文《文献综述》的写作方法
一、什么是文献综述
对某一领域的问题,进行了相关的系统查阅和分析,以了解该领域研究状况的过程。
我们的目的是要了解毕业设计选题在该研究领域中的地位,以及你确立本题研究的起点。
二、对象
以艺术设计权威的、优秀的专家观点文章为主,要找前沿的理论研究或实践研究的文章。
要用第一手资料。
三、撰写文献综述方法
1搜集阅读艺术设计专家观点8—10篇文章
2你要写的文献综述必须引用三人以上的专家原话原文
3归纳、整理、分析、引用专家原话、找出其文献的优缺点
4专家观点(原文)对你本次毕业设计有什么指导意义,结合自己做毕业设计的体会,说出你对专家观点的运用、或超越专家观点(或对专家的观点提出批判),并确立学生本人研究的观点,进而结合自己的毕业设计进行论述(你专家观点对你毕业设计有什么样的具体指导作用,越具体越好,或你对专家的那种观点提出批判、在他的基础上你屏弃什么观点、你发展什么观点)。
五、应注意的几点
①真实性:文献分析应尽可能针对第一手资料及权威的有代表性的观点;
②全面性:不能仅凭一两篇文章就下结论;
③针对性:不要把不相关的观点和资料罗列出来;
④实效性:要以当前近期发表的资料为准。
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⑤“参考文献”内容的字数要求大约在500—800字之间,《文献综述》全文要求2500字。
6.在研究报告(毕业论文)写作结构中的位置
外文文献翻译
外文文献翻译要求;
1\查找英文文章,要求是英文原文,文章内容要与自己毕业设计有关的文献,文章并能够支持本次毕业设计.
2\文章内容必须是关于平面设计类的内容.
3\文章内容必须包含标志\招贴\包装三方面以上.
4\根据这篇英文原文翻译成汉语(翻译成汉语这篇文章要求4000字)
毕业设计说明
根据本次自己的毕业设计内容撰写文章;
1、找文献到市场调研
2、自己构思、画草图、进行创作
3、围绕标志、包装、招贴、型录四方面内容写
4、部分内容可以参照开题报告、题目论证书来写,但不能照抄原文。
5、主要内容写你是怎样进行毕业设计的,具体写你是怎样做的(毕业设计说明文章要求2500字)。