外文文献原稿和译文
毕业论文外文文献原文及翻译
北京联合大学毕业论文外文原文及译文题目：网络口碑营销策略研究专业：工商管理指导教师：吴印玲学院：管理学院学号： 2010110404332 班级： 20101104043 姓名：杨倩一、外文原文Traditional media and word of mouth is always intertwined——Sanofi Wizz, (U.S.) The past, often produced media advertising professionals, these elements arewritten by the reporter, edited revision last beautifully packaged and then. Now, wehave moved away from the presentation of this refined and processed. Now, we havelost the patience to watch the beautiful advertising audience, after all, the advertisingsales media, exhibition, broadcast, very difficult to have as in the past, forcing theaudience had watched.Now, people can search engines and blog, like la carte as on-demand news. Peopledo not always read the story of the original, on the contrary, people can go deep intothe intermediate links, links, reading these stories. You are free to enter into a certainperson's blog, the three of you search the contents of the things this person involved inthe blog, but for such content, you know nothing about this person's blog, you canalso link more blog to other content. Now posted on the website's content is often raw,authentic things, the search engine provided by the consumer to capture thisinformation, these unrestrained, not veiled, to the point of thinking they unfoldedbefore our front. Bloggers have become a thinking experts, they are full-text excerpts,after re-arrangement and combination, and then offer to the general audience,dedicated to those willing to receive such information.Even the norms of the kind of news articles, can not get rid of the threat of thevoice of the customer. Now, many traditional media have chosen a new way, theirstories and popular blog title link to completely break the news editor of the shacklesof the wall and the ring caught. Although the official news story is statically publishedon a web page, however, the side of the page link will automatically displayinformation from the blog - the content is no editorial filter. Soon, we will be from thehand of the newspaper to see the contents of this form.Let us look at the work in public relations representative. The public relations onbehalf of young, hard-working, newspapers high in a gesture to see a fictional story,the story with his client. So he give colleagues sent an e-mail related things to tellthem, and then turned around and walked into the boss's office, told the boss the news. However, when he reach the boss's office, when his boss to remove the page, the story has long been endemic - the next in the story, already appeared threatening the blog title.Therefore, you have to do is: to ensure a true, reliable reputation. We can not control the customer comments, so be sure to keep in mind, the finished article, does not mean the end of the public relations. Our goal is to continue to win the good reputation on the basis for sustainable development.For those who do not keep their promise to businesses, the search engines so that they feel especially frightened. Let us take a look, if you spend a lot of money, engine marketing activities, there will be what kind of situation. Designed some very fine small ads on the bottom of the page that says: "click here, great." Of course, web pages, more links are from real consumers, you'd better is to make consumers happy, satisfied, otherwise, they released post will overwhelm any other paid advertising posts.We take a look at the practice and suffered a large cable company, not to mention its name, the companies often do not fulfill their service contract, the customer service very poor quality, often offensive to customers, so repeatedly, so that customersvery angry. If you have online access to this company, you will see what kind of information? We see expensive advertising, news stories from the official reports - as well as messages posted by thousands of angry customers. We are pleased to see that this company do a little hands and feet, and consumer reviews changes to their advertising and they put together, they are never likely to again spend money on online advertising.Why is there such a result? Blog written by those who complain, blame or words of praise, how will have a big impact, far more than the influence of the "Times" or "Newsweek"? The reason is that the blogger is a member of our team - and the team search for the information, the team members concerned about them through word of mouth to share these views and opinions. If certain members of the team rant, saying that a piece of software suddenly, inexplicably, on the hard drive removed, his criticism and scolding will be hundreds of other sites excerpt, and every one website has its own followers. In this way, everyone, whenever you see one such comments will immediately Click to view details - so they can know in the end destroy that personal computer which software company.Each of a traditional newspaper or magazine, has 1 000 sites corresponding to In today's media than traditional media have more freedom and an independent voice. Moreover, it can be more convenient, fast and cheap to see some new comments, so these remarks spread more widely.Must learn to adapt to such a complex, chaotic world. Must know, people have been talking about you, their words positive and profound content of the speech, and everywhere.Marketing staff ignored these remarks will be seen as cold and incompetent, and will not be able to attract attention and attention. Marketers learned how to interact with clients, learn how to participate in customer reviews, learn how to make people's comments play an active role in the learning will flourish.二、译文传统媒体和口碑永远交织在一起——(美)塞诺威兹过去，往往是专业人员为我们制作媒体广告，这些内容都是由记者撰写、经过编辑校订，最后经过精美包装而后提供的。
外文文献原稿和译文
外文文献原稿和译文原稿MechanicalandRegenerativeBrakingIntegrationforaHybridElectricVehicleAbstract,namelyanelectricmotorandinternalcombustionengine,whichallowtheelimina tionofidling,,theaddedcostofthehybridelectricsystemhashinderedthesalesofth esevehicles.JapanNorth America automotive companieshavedevelopedandreleasedforsaletheirownhybridelectric unpredictablegasprices,thesalesofhybridelectricvehicleshaveincreaseddramat ically inrecentyears.2.1.1HybridConfigurationsForthepast100yearstheobjectiveofthehybridhasbeentoextendtherangeofelec tricvehiclesandtoovercometheproblemoflongrechargingtimes35.Therearethree ,par allelhybridsandseries/parallelhybrids.Eachconfigurationhasitsadvantagesanddisadvantageswhichwillbediscussedi nthefollowingsections.SeriesHybridsInserieshybridsthemechanicaloutputfromtheinternalcombustionengineisuse dto driveageneratorwhichproduceselectricalpowerthatcanbestoredinthebatteriesor highpowersystemssuchaslargetrucksorlocomotivesbutcanalsobeusedforlowerpowe rpassengervehicles18.2.1.2‘degreeofhybridization’toquantifytheelectrica lpowerpotentialofthesevehicles.ThedegreeofhybridizationrangesfromDOH=0foraconventionalvehicletoDOH=1f oranallelectricvehicle25.Asthedegreeofhybridizationincreases,asmallerICEcanbeusedandoperatedclosertoitsoptimumefficiencyforagreaterproportionoftheti me,.MicroHybrid MicrohybridshavethesmallestdegreeofhybridizationandusuallyconsistofanintegratedstartergeneratorISG2.1.31500 kg100 km/h0 km/h0 km/h50 km/h2.1.42.1.5译文混合动力电动汽车机械和再生制动的整合摘要为了减少对环境的污染和车辆的燃油消耗,混合动力电动汽车已经成为汽车工业的首选方法;混合动力电动汽车通过使用由电动马达和内燃发动机组成的混合动力系统来达到减少环境污染和燃油消耗的目的;混合动力系统消除了怠速,使发动机以一种更有效的方式运行,增加了再生制动的使用;但是,混合动力的成本的增加阻碍了这些车辆的销售;在这里提出一个更具成本效益的电液制动系统的设计;该系统使用电控机械结合的控制方式控制制动助力器产生的推动力,并有足够的时间反应;这个系统使驾驶员清楚地了解机械和再生制动力矩的混合,使再生制动力系统得到有效的控制;一个系统化的设计过程是其次,重点在于展示概念设计方案的可行性和使用虚拟和实物模型的初步设计功用;虚拟和实物模型的结合使用成为验证和开发系统的强大工具,本文将介绍和讨论在设计过程中模型所起到的作用;因为在设计过程中设计者可以获得相关的经验,提倡学生设计实物模型,以提高学生的学习经验;很明显,这正是本文所要提出的;现代混合动力电动汽车随着油价的上涨和环境保护意识的提高,消费者和政府迫使汽车行业开始生产省油和对环境污染小的汽车;一个有前景的方法就是现在实行的混合动力电动汽车;混合动力汽车指的是有两个或两个以上动力来源的车辆;混合动力汽车动力的来源可能有很多的不同,但是现在混合动力汽车最常见的布局是由内燃发动机和电动马达,能量储存系统共同输出动力,这样的车辆就叫混合动力电动汽车;汽车可以同时使用发动机和电动马达输出的动力,从而可以提高汽车的使用性能和效率,进而又可以提高燃油经济性,减少废气的排放,同时还能满足消费者对汽车性能的要求;1997年,丰田成普瑞斯为了第一款混合动力电动汽车,在日本进行了批量生产;本田公司花费了三年的时间进行混合动力电动车的生产,然后进军北美市场;丰田普瑞斯在北美发行几个月后,本田Insight紧随其后也在北美进行发行;混合动力电动车具有再生制动系统的独特优势;在制动过程,通常用于动力输出的电动马达,可以起到发电机的功用,把汽车的动能转化为蓄电池的电能,而不会转化为热能浪费掉;转换的电能可以储存到蓄电池中,然后可以作为电动马达驱动汽车使用的能量;考虑到蓄电池能量密度时,动能转换为电能这个过程就更加重要了;能量密度是指单位体积或质量下能量储存系统所储存的能量;为了说明这一点,我们可以做个对比,4.5公升的汽油通常可以维持一辆汽车行驶50千米;而要把相同的能量储存到蓄电池中,则需要一个质量约为270千克的铅酸蓄电池;这就说明了在汽车行驶过程中能够有效地储存再生制动系统产生的能量的重要性,从而可以保证在提高混合动力电能车性能的前提下,不至使能量储存系统所占体积过大;再生制动系统研究范围本文所提出的再生系统的研究范围是研究再生制动系统和机械制动系统之间相互作用的关系,目的是设计开发出一个低成本的再生制动系统,从而可以应用到未来经济型的混合动力电动汽车上;这个系统可以根据驾驶员的需要进而控制再生制动系统和机械制动系统产生的制动力矩的结合,还应该保证这个过程的平顺性和安全性;再生制动力矩是通过使用的异步电动机的矢量控制算法进行控制的;但是,独立地控制制动踏板产生的机械制动力矩,同时又要保持机械制动系在再生制动系统失效后起到备用作用,这是一个很大的难题;为了解决这个问题,需要研究一个通过减少制动主缸内制动液压来来控制机械制动系统产生的制动力矩的制动系统;混合电动汽车概述混合动力电动车已经成为了可以在短时间内减少汽车污染排放和提高燃油经济型的解决方法之一;在过去的10年几乎所有的主要汽车公司都已经向公众发行销售自己的混合动力电动汽车,混合动力电动汽车的普及和销售在这个世纪有了很明显的增长,随着不可预测的汽油价格的增长和对环境保护的关注,混合动力电动汽车的销售将在最近几年内急剧增长;2.1.1混合动力装置在过去100年来混合动力的研究目标是延长电动汽车的使用寿命,解决蓄电池的长期充电问题;在目前市场,现在主要有三种混合动力装置,这些混合动力装置为串联混合动力,并联混合动力,串并联混合动力;每一种动力装置都有其优点和缺点,这将在以后的章节进行讨论;串联混合动力串联混合动力汽车使用发动机输出的动力来驱动发电机产生电能,这些电能可以储存在蓄电池中,也可以用来驱动电动马达来驱动汽车;在串联混合动力汽车上,发动机和驱动轮之间没有直接的机械连接,串联混合动力往往在高功率系统中使用,如大型货车或火车,也可以应用到低功率的客运车辆上;发动机输出的机械能和蓄电池输出的电能可以通过电子控制器进行控制接合,然后这个电子控制器通过比较驾驶员所需的动力和汽车车速,电动马达输出的转矩,从而决定每个动力源驱动汽车行驶所要输出的能量;在制动过程中,这个电子控制装置可以使电能输出模式转换为再生模式,直接把再生制动系统产生的电能储存在蓄电池内;按照这种布置方式进行设计有很多的优点;发动机可以保持高效率的运行,使发动机产生的电能在蓄电池和驱动马达之间得到分配;发动机在其最高效率的工况下运行,排放可以大大降低,燃烧每体积的燃料可以产生更多的电能;因为串联动力装置结构简单且成本低,这种动力装置很容在汽车上落实;并联混合动力在并联混合动力汽车中,发动机输出的机械功传到变速箱中;发动机输出的机械功和电动马达输出的功在变速箱内进行机械式的接合,混合的机械功用于驱动汽车行驶;在这种混合动力装置结构中,发动机和驱动轮之间有直接的机械连接;在串联混合动力装置中,电子控制器通过比较驾驶员所需的动力和汽车车速,电动马达输出的转矩,从而决定每个动力源驱动汽车行驶所要输出的能量,以满足汽车行驶性能,获得最佳的效率;正如串联混合装置一样,并联混合动力也以相似的方法控制再生制动;并联混合动力装置通常应用到低功率的电动车中,这两种驱动力可以同时使用,提供更高的行驶性能;与串联混合动力系统相比,并联混合动力系统有很多优势;其中最重要的一项优势是效率高,因为在并联混合动力中,电能和机械能只需转换一次,而在串联混合动力中,电能和机械能需要两次转换;由于并联混合动力可以使发动机和电动马大产生的动力同时结合起来,在不损失汽车行驶性能的前提下,可以使用体积小的电动马达,同时也降低了油耗和排放;最后,并联混合动力汽车在行驶过程中只需使发动机运行,而不需要另一个发电机为蓄电池充电;串、并联混合动力串并联混合动力装置结合了串联和并联动力装置的特点;这种混合方式汽车通过使用动力分配装置来控制双动力源电动马达输出动力,发动机输出动力或者两者同时输出驱动汽车行驶;虽然这种装置形式可以获得串联混合动力装置和并联混合动力装置的优点,因为考虑到汽车实际行驶可能性,这种装置的控制算法会变得非常复杂; 2.1.2混合度现在道路上行驶的混合动力电动汽车大多是串联混合动力,并联混合动力,或者串并联混合动力,因此定义一个‘混合度’变量来评价混合动力电动汽车的电能潜能是非常有意义的;混合度变从传统车辆DOH=0到所有电动车DOH=1之间变化,随着混合度的增加,在汽车上可以使用一个比较小的发动机,同时发动机可以在最接近最佳效率的工况下运行很长的时间,这样就可以减少燃油的消耗和废气的排放;电动马达输出的功用P表emP表示;示,发动机输出的功用ice微混合动力微混合指的是最小混合度,通常是由一个连接到发动机曲轴的综合起动发电机组成;在加速和怠速过程中,综合起动发电机使发动机处于关闭状态,从而节约燃油;加速时,在燃油喷入汽缸之前,综合起动发电机使发动机的曲轴加速旋转;在加速过程中,综合起动发电机对发动机起动协助的作用,在制动过程中,综合起动发电机还可以作为发电机向蓄电池充电;和非混合动力汽车相比,微混合动力汽车的燃油经济性可以提高10%左右;轻混合动力轻混合动力和微混合动力结构相似,有一点不同的是其综合起动发电机是经过改进的,其输出的动力可以超过20KW;但是,轻混合动力的能量储存系统只能储存1KWh左右的能量;轻混合动力汽车只有一个很短的纯电动续航能力,但是可以在加速过程中给发动机提供很大的辅助作用;轻混合动力中的电子元件要比微混合动力中的电子元件复杂的多,且在汽车行驶过程中发挥着更大的作用;和非混合动力的汽车相比,轻混合动力汽车的燃油经济性可以提高20%-25%左右;全混合动力在全混合动力汽车上不再使用综合起动发电机,取代它的是一个独立的电动马达和交流发电机、起动机,这些装置也可以起到综合起动发电机的作用;电动马达可以独立驱动汽车行驶,尤其是在城市道路上走走停停的行驶;能量储存系统也得到了改进,这样就提高了汽车纯电动续航能力,减少了发动机的体积,从而提高燃油经济性和减少排放;与非混合动力汽车相比,全混合动力汽车的燃油消耗量可以减少40%-50%;插电式混合动力插电式混合动力汽车在结构上和全混合动力汽车相似,不同的是插电式混合动力汽车有一个比较大的能量储存系统,可以通过与外部电源连接进行充电;在蓄电池储存能量范围内,可以通过电动马达来驱动汽车行驶,但是当蓄电池的能量降到一定水平后,其运行形势就和全混合动力一样了;2.1.3再生制动原理混合动力电动汽车最重要的特点是可以回收大量的制动能量;在制动过程中,电动马达可以作为发电机来运行操作,将制动过程中的动能转换为电能储存到蓄电池中,这些电能就可以被汽车重复使用;但是,车辆的制动性能就将影响到汽车的安全性;在紧急制动状态下,汽车的制动距离要尽可能的短,还要保证制动时汽车有较好的方向稳定性;汽车具有较好的方向稳定性,就需要控制车轮的制动力分配;一般来说,制动时所需的制动力矩比电动马达产生的制动力矩大得多;因此,机械制动系统需要和电子再生制动系统同时存在,这就需要适当的设计以保证制动时的操作稳定性,不至于影响到汽车的安全性;制动时能量消耗由公式可得,一个质量为1500Kg的汽车以100km/h初速度制动到完全停止,需要消耗的动能;如果这些能量的25%可以通过再生制动系统进行回收,当忽略制动和加速过程中的空气阻力,机械摩擦和滚动阻力,假设电动马达的工作效率100%,利用公式可以估算出,这些能量可以使汽车从0km/h加速到50km/h.这就表明,当汽车行驶在城市道路上,汽车不停加速和制动,混合动力电动车的燃油经济性可以大大增加;需要注意的是,制动能量的回收量受到马达的型号和能量转换率的限制;2.1.4再生制动系统目前,通常使用的有两种再生制动方法;这些方法通常称为串联再生制动和并联制动,每种制动策略都有其优点和缺点,本文对此将进行具体讨论;并联再生制动在并联再生制动系统中,电动马达和机械制动系统同时工作,从而使汽车减速;因为机械制动系统不能独立的控制制动力,使制动时的能量转换为热能而不是电能,因此这不是最有效地再生制动方法;但是并联再生制动结构简单成本低,这就成为其一大优势;并联再生制动的机械制动系统只需要稍加修改,而且电动马达的控制算法也可以很容易在汽车上实现;这种制动方法还有一个额外的优势,当再生制动系统发生故障时,机械制动系统可以起到备用的作用;串联再生制动在串联再生制动中,电动马达只有在制动时才起作用;只有当电动马达和能量储存系统无法接受更多制动时所需的能量时,再生制动系统才起作用;串联再生制动需要独立的控制制动力矩,串联再生制动可以高效率的把动能转换为电能,这是其一项优势;但是它的不足之处在于,制动系统结构复杂,成本高;这种制动方式需要制动踏板模拟器,制动系统也需要重新设计,这都会增加其制造成本;因为制动系统需要装有传感器和信息处理器,这就会增加了结构的复杂度;2.1.5目前的再生制动系统目前大多数混合动力电动汽车的再生制动系统都是比较昂贵的电液制动系统;再生制动系统使用制动踏板模拟器来建立驾驶者的制动需求,这个制动踏板模拟器与液压制动电路独立分开;这样再将制动需求按照一定比例转换为再生制动和机械制动需求,然后将机械制动需求发送到由高压液压泵,蓄能器和比例控制阀的系统;比例控制阀根据制动需求,控制制动液以一定的预定值流到每个车轮的制动轮缸中;。
外文文献翻译(图片版)
本科毕业论文外文参考文献译文及原文学院经济与贸易学院专业经济学（贸易方向）年级班别2007级 1 班学号3207004154学生姓名欧阳倩指导教师童雪晖2010 年 6 月 3 日目录1 外文文献译文（一）中国银行业的改革和盈利能力（第1、2、4部分） (1)2 外文文献原文（一）CHINA’S BANKING REFORM AND PROFITABILITY（Part 1、2、4） (9)1概述世界银行（1997年）曾声称，中国的金融业是其经济的软肋。
当一国的经济增长的可持续性岌岌可危的时候，金融业的改革一直被认为是提高资金使用效率和消费型经济增长重新走向平衡的必要（Lardy，1998年，Prasad，2007年）。
事实上，不久前，中国的国有银行被视为“技术上破产”，它们的生存需要依靠充裕的国家流动资金。
但是，在银行改革开展以来，最近，强劲的盈利能力已恢复到国有商业银行的水平。
但自从中国的国有银行在不久之前已经走上了改革的道路，它可能过早宣布银行业的改革尚未取得完全的胜利。
此外，其坚实的财务表现虽然强劲，但不可持续增长。
随着经济增长在2008年全球经济衰退得带动下已经开始软化，银行预计将在一个比以前更加困难的经济形势下探索。
本文的目的不是要评价银行业改革对银行业绩的影响，这在一个完整的信贷周期后更好解决。
相反，我们的目标是通过审查改革的进展和银行改革战略，并分析其近期改革后的强劲的财务表现，但是这不能完全从迄今所进行的改革努力分离。
本文有三个部分。
在第二节中，我们回顾了中国的大型国有银行改革的战略，以及其执行情况，这是中国银行业改革的主要目标。
第三节中分析了2007年的财务表现集中在那些在市场上拥有浮动股份的四大国有商业银行：中国工商银行（工商银行），中国建设银行（建行），对中国银行（中银）和交通银行（交通银行）。
引人注目的是中国农业银行，它仍然处于重组上市过程中得适当时候的后期。
第四节总结一个对银行绩效评估。
外文文献原文及译文
附录1 外文文献原文及译文原文：An evaluation of NDT methods for the location and sizing of forging discontinuitiesIn selecting an NDT method for flaw detection in forgings a number of variables must be considered:a) the type of discontinuity to be assessed;b) the method to be used for detection and evaluation, andc) the variables associated with the forging itselfThe variables in item a) will govern the location within the forging and its orientation with respect to a particular surface Item b) could include a considerable array of NDT methods, but for the purpose of this paper only the six most widely used are considered一visual testing (VT), penetrant inspection(PI), magnetic particle inspection(MI), eddy current testing (ET), radiographic inspection (RT) and ultrasonic inspection (UI). In the last item c) the component race include such things as condition, geometry access for inspection.a)Forging discontinuitiesThe location of the discontinuity will have a significant influence on the selection of the NDT method to be used and they are therefore grouped into three categories, to aid this selection:1. open to the surface: laps, seam, burst, slugs, cracks and inclusions2. slightly subsurface: seam, stringers, inclusions and grain structure variations3. internal: stringers, burst, lamination, grain structure, inclusions and pipingA brief review of these terms may be helpful:Lap: folded metal, flattened into the surface but not fusing with itSeam: linear flaws due to oxidized blow holes or ingot splashes, which are elongated by hot workingBurst:ruptures caused by failure of plastic deformation by processing at too low a temperature or excessive working of metalStringers: a bar stock defect, due to non metallic inclusions being squeezed out into long and thin stringsLamination: planar defect aligned parallel to surface, originating in the original ingot from rolled out pipingCracks: transgranular failure, due to localized stresses resulting from non-uniform heating or cooling and non-plastic deformationInclusions: impurities, such as slag, oxide and sulphides, often from the original molten stage in forming the billet used for forgingGrain structure: depending upon the extent of working, (deformation and recrystllisation) can be as small as 0.5mm or as large as 10mmPiping: a cavity at the centre of the ingot or billet, caused by shrinkage during solidification Slug: a piece of foreign matter that has been pressed or rolled into the surface of the material b)The NDT MethodVT—visual testing is the oldest of the NDT methods but still valid and widely used today The system is based upon observation, usually by a human observer, but now increasingly by digital/video cameras which use pattern recognition to locate dissimilar areas in a surface. The sensitivity will depend upon the method but typically a good observer with simplevisual aids can resolve 0.5mm differences aids will include magnifying glasses (up to x10), microscopes(up to x100) and fibred-optic bores copes and endoscopes for viewing internal details in hollow or complex sections. The system is used for surface inspection only with costs in the range $4 to $4000.PT一the surface is covered with brightly covered oil (typically red or fluorescent), which will penetrate any surface openings. After removal of excess, an absorbent, white powder is applied, which draws any trapped oil to the surface. This creates an indication of the presence of the surface opening. This process, like visual inspection, also requires visual acuity, but the indications are ‘enhanced’ by the process, since‘bleed-out’ spreads the visual image. Costs can range from as little as $4 for a couple of cans, to $8000 for a process ‘line’. Both VT and PT are surface inspection systems only arid will therefore detect only those discontinuities that have a definite surface opening Surface cleanliness is very important, particularly with PT.MT一ferromagnetic materials carrying a large flux density; retain the presence internally, with little external evidence other than at the poles. Any discontinuity in the material will disturb this uniform flux and create a small ‘leakage’ at the site of the discontinuity. This leakage can be detected by the fact that finely divided; ferromagnetic particles collect at the-site, creating an indication. As with PT, the particles can be colored, to increase contrast, which when viewed under suitable lighting, create a clear visual image of the discontinuity. However, unlike PT the leakage can pass through thin layers of paint or plating materials, so that the discontinuity does not have to be open to the surface. The system can therefore detect surface AND slight subsurface discontinuities. However this is only possible in ferromagnetic materials, such as iron, mild and tool steel, nickel, cobalt and martenstic stainless. It will not operate on Paramagnetic or Diamagnetic materials, such as copper, aluminum and austenitic stainless steel. A small electromagnet can cost as little as $200, but a large `bench type' machine can cost up to $10 000 and the cost of electricity can be substantial.ET一Direct current flowing in a coil, sets up a longitudinal magnetic, field through the coil, and exhibits a particular resistance to flow. If the current is alternating, then a further effect一inductive reactance, adds to this resistance, the total being impedance. This impedance also causes a lag between the current and the voltage, called a phase shift. This shift and impedance are characteristics of the coil.If the coil is now placed close to a conducting surface, the reversing magnetic field induces a reversing current in the conducting (eddy current) which opposes the inducing field. This opposition alters the impedance of the coil and a suitable instrument can detect these changes (both phase angle and/or impedance).For a given ,discontinuity-free surface , a specific alteration will be present which can be zeroed .If the coil now passes over a discontinuity, a change in induction will occur which will be registered by the instrument. However, a change in the conductivity of the material will also effect the induction, as will changes in permeability. Thus, non-uniform heat treatment, segregation and in homogeneities in material composition and structure will also effect the induction and create an ‘indication’. Another critical factor is the distance between the coil and the test surface. This ‘lift off’ can be used in a positive way to determine coating or paint thickness’, on conducting materials. But equally, differences in the coil/specimen gap can result in non-relevant signals. The system can therefore detect surface AND slight subsurface discontinuities. However this is only possible in conducting materials and the proximity of the test coil to the test surface is critical. This means that for any component (other than flat plate), special probes are usually designed to follow specific component contours. A small eddy current machine can cost as little as $2000, but a large automated machine can cost upto $20 000RT一Short wavelength, electromagnetic radiation will pass through many materials, depending upon density and thickness, and then create a range of exposures on either film or a fluoroscopic screen, to present a visual image of the internal composition of the item. Differences in absorption within the material due to such things as gas holes, cracks and bursts will create photographic density differences on the film or detector, which can be interpreted by trained personnel. The source of radiation can be an X-ray tube or a gamma source (such as Iridium or Cobalt) and the images can be generated on either film or as real-time images on fluoroscopic screens. Defect orientation is a vital factor in radiography since it is thickness differences, which the process detects. Hence, a lamination type defect, parallel to the film would be almost impossible to detect. On the other hand, a crack perpendicular to the film would almost certainly be detected. It is therefore often the case that a single component would have to be radio graphed from more than one direction, in order to detect most defects. Finally, the radiation used is highly hazardous and therefore any environment in which it is used, must suitably shielded, to prevent exposure of the operator. As well as shielding the use of X or gamma rays will also require, monitors, alarms, interlocks and personal dosimetry systems, which along with the film itself, adds to the cost.A basic X-ray set up would cost around $10000 and with ancillary equipment and film could cost $3000 per year to run.UT—At an interface between materials of differing acoustic impedance, a sound wave will have a proportion reflected and the remainder transmitted. Thus a gas hole or crack in a forging will reflect a sound beam because of their large difference in acoustic impedance with the metal structure containing them. Since ultrasound travels in a given material at a known (predictable) velocity, then the distance to a reflector will be a direct function of this time of flight of the pulse of sound. Its location can therefore be estimated .Since the amplitude of the returning signal is also related to the size of the reflector, then an approximation can be made of the extent of the reflector, in terms of length through-wall thickness and width. The data can be presented as an ‘A’scan, on a cathode ray tube (requiring skilled interpretation) or as a ‘B’ or ‘C’ scan, where the data are plotted on printers or strip charts as a permanent record. Depths of penetration can be adjusted (by calibration and probe selection) from 10mm to 3 meters in suitable, fine-grained material. However cast, or large grained forged material, could be attenuate signals to the extent that they are untestable. A typical portable flaw detector and probes would cost around $5000, a fully automated ‘C’ scan immersion system could cost $2000.c)The variables associated with the forging1.Surface conditionFor VT and PT surfaces better than 6.3um Ra would yield the best results. For MT a similar situation exists, where a confusing background could result from rough surfaces. ET also requires a smooth a surface for preference, since ‘lift-off’ effects could be unacceptable. For RT a surface roughness exceeding 1% of material thickness could result in a significant loon of sensitivity. However for UT, a suitably viscous ‘couplant’could assist in sound transmittance, but entry surface ‘noise’on the timebase and attenuation would reduce sensitivity.2.GeometryFlat surfaces are the simplest to inspect, by any method. However, PT is least influenced by geometry, being a liquid process. MT requires that the flux be at 90 to the discontinuity and thus, curved surfaces and hollow sections offer particular problems. VT may require special access equipment and ET will need specially designed probes for curved or irregular surfaces. Since RT relies on absorption differences, variations in thickness due to curvaturewill result in large variations in photographic density and a consequent loss of film contrast. In UT the probe has best transmittance when it is whole face is in direct contact with the surface. Any curvature will result in “rocking”of the probe and a consequent loss of “coupling” and reduced signal amplitude.plexityForged bar, billet, rod and plate offer simple shapes for inspection, but aircraft landing gear is an entirely different manner. PT is the least influenced by complex shapes when using the water washable system VT will require longer inspection periods and aids such as mirrors and bores copes. For MT, the more complex the shape, the more difficult it is to arrive at an all over procedure and individual flux/current tor the various sections ET will again require specially shaped probes and RT a larger number of film exposure and angled shots UT will need careful planning to ensure complete coverage and may not be possible if access is limited.4.ThicknessVT, ET, PT and MT are all unaffected by thickness since they are surface methods. RT has an approximate thickness limit of 300mm in steel and at 2% sensitivity (a typical value), will only record discontinuities of 6mm maximum section, in the plane of the radiation. UT is capable of inspecting beyond 2 meters in fine-grained material but is less effective below 10mm or so.5.Discontinuity OrientationVT and PT are unaffected by orientation. In MT, for maximum sensitivity the flux should be at right angles to the discontinuity. ET requires that the discontinuity be at right angles to the coil windings and RT has its maximum sensitivity when the discontinuity lies parallel to the radiation beam. UT has the maximum response when the reflector is at right angles to the sound beam.译文：对铸件缺陷位置和尺寸的无损检测方法的评价对铸件裂纹探测时，选择无损检测方法必须注意以下几点：a)评定缺陷类型；b)确定评定和探测缺陷的方法；c)铸件自身相关的变化。
外文文献原稿和译文
外文文献原稿和译文原稿The water level control circuit designWater source total ranks sixth in the world, per capita water resources is only a quarter of the world per capita consumption, and geographical distribution is very uneven, the vast region north of the Yangtze River, northin most parts of the medium-sized cities in the dry state, water shortage has become an important factor restricting China's economic development. Reasonable use of water resources has become an important issue for China is now facing. In order to achieve the rational use of water resources, in addition to in beefing water conservancy projects and enhance the people's awareness of water conservation efforts to improve. But more important is the application of new technical information, real-time to accurately understand and master a variety of hydrological information in order to make the right water scheduling and management, so that preventive measures to minimize water wastage . Coupled with long-standing water level measurement of water level has been an important issue in hydrology, water resources department. For the timely detection of the signs of the accident, precautionary measures in the future, economical and practical, reliable water level wireless monitoring systems will play a major role. The water level of dam safety, one of the important parameters for water drainage and irrigation scheduling, water storage, flood discharge.Provides a good foundation for the automation of monitoring, transmission and processing of the water level reservoir modernization. Need to monitor the water level in many areas of industrial and agricultural production. The site may not be able to close without the manpower to monitor, we can RMON, sitting in the control room facing the instrument can be monitored on-site, convenient and save manpower. In order to ensure the safe production of hydroelectric power station to improve power generation efficiency,Hydropower production process need to monitor the water level in the reservoir, trash rack, pressure drop and the tail water level. However, due to the different power plants with a different factual situations, have different technical requirements, and the measurement methods and location of the water level parameters and also the requirements of the monitoring equipment. This often results in the monitoring system equipment of a high degree of variety, interchangeability is not conducive to the maintenance of equipment will increase the equipment design, production, installation complexity. Therefore, on the basis of the actual situation and characteristics of the comprehensive study of hydropower water level monitoring, the use of modern electronic technology, especially single-chip technology and non-volatile memory technology, designed to develop a versatile, high reliability, easy maintenance, the applicable a variety of monitoring the environment, multi-mode automatic water level monitoring system has important practical significance. The subject according to the reservoir water level measurement needs, design a remote microcontroller water level monitoring system, the system automatically detects the water level, time processing, Data GPRS remote upload function. The design of the monitoring system will be significant savings in manpower and resources, low-power 24 hours of continuous monitoring and upload real-time control reservoir water level, to better adapt to the needs of the modern water level measurement, the safety of the dam reservoir, impoundment spillway to provide a basis.Microcontroller embedded microcontrollers are widely used in industrial measurement and control systems, intelligent instruments and household appliances. In real-time detection and automatic control of microcomputer application system, the microcontroller is often as a core component to use. The basic requirements of the water tower water level control system in the case of unattended automatic limit automatically start the motor to reach the water level in the water level in the water tower to the water tower water supply; water tower water level reached the water level upper limit is automatically off the motor to stop water supply. And unusual time to sound the alarm and troubleshooting in the water supply system at any time to ensure that the towers of the external normal water supply role. The water tower is often seen in daily life and industrial applications, water storage devices, external water supply through the control of its water level to meet the needs of its waterlevel control is universal. Regardless of socio-economic rapid water plays an important role in people's normal life and production. Once off the water, ranging from great inconvenience to the people's living standards, weight is likely to cause serious accidents and losses, and thus a higher demand of water supply system to meet the timely, accurate, safe and adequate water supply. If you still use the artificial way, the labor-intensive, low efficiency, safety is hard to guarantee the transformation of the automated control system, which must be carried out. In order to achieve sufficient amount of water, smooth water pressure, water towers, water level automatic control design low-cost, high practical value of the controller. The design uses a separate circuit to achieve high and low warning level processing, and automatic control, save energy, improve the quality of the water supply system.SCM is an integrated circuit chip, VLSI technology with data processing capability of the central processing unit CPU random access memory RAM, read only memory ROM, and a variety of I / O port and interrupt system, timers / timer other functions (which may also include a display driver circuit, pulse width modulation circuit, analog multi-channel converter, A / D converter and other circuit) integrated into a silicon constitute a small computer system. The basic features are as follows: the chip is small, but complete, SCM is one of the main features. Its internal program memory, data memory, a variety of interface circuit. Large processor speed is higher, the median more of the arithmetic unit, processing ability, but need to be configured in the external interface circuit; microcontroller clocked generally 100MHZ less suitable for small products for independent work, cited pin number from a few hundred. The application is simple, flexible, and free assembly language and C language development of SCM products. The working process of the microcontroller: microcontroller automatically complete the tasks entrusted to it, that is, single-chip implementation of the procedure for a section of the instruction execution process, the so-called directive requirements for single-chip implementation of the various operations used in the form of the command is to write down , which corresponds to a basic operation of designers assigned to it by the instruction set, an instruction; Full instructions can be executed by the microcontroller, the microcontroller instruction set, the different types of single-chip, and its instruction set is also different. So that the microcontroller canautomatically complete a specific task, the problem to be solved must be compiled into a series of instructions (these instructions must be selected microcontroller to the identification and implementation of the Directive), a collection of this series of instructions to become the program, the program need to pre- stored in the components - memory storage capabilities. Memory is composed by a number of storage units (the smallest unit of storage), like a large building has many rooms composed of the same, the instructions stored in these units, the instruction fetch unit and perform like the rooms of large buildings, each assigned to only a room number, each memory cell must be assigned to a unique address number, the address is known as the address of the storage unit, so as long as you know the address of the storage unit, you can find the storage unit that stores instructions can be removed, and then be executed. Programs are usually executed in the order, instruction program is a sequential storage, single-chip in the implementation of the program to be able to a section of these instructions out and be implemented, there must be a component to track the address of instruction where this part the program counter PC (included in the CPU), the start of program execution, endowed the address where the first instruction of the program to the PC, and then made for each command to be executed, the PC in the content will automatically increase, increase The amount is determined by the instruction length of this article may be 2 or 3, to point to the starting address of the next instruction to ensure the implementation of the instruction sequence.Microcontroller tower water level control system is the basic design requirements: inside the tower, we have designed a simple water level detection sensor used to detect the three water level, the low water level, the normal water level, water level. Low water to give a high single-chip, driven pumps and water, the red light; water level in the normal range, the pump add water, the green light; high water when the pump without water, the yellow light. The design process using the sensor technology, microcomputer technology, and light alarm technology and weak control the strong power of technology. Technical parameters and design tasks: 1, the use of the MCU to control the water level on the tower;, the water level in the water level detection sensor probe was the tower to give the microcontroller in order to achieve the water pump and water system and display system control; 3, the light alarm display system circuit, pumps and hydropower route relaycontrol;, analysis is drawn on the working principle of the system structure and a system block diagram using the microcontroller as a control chip, the main work process when the water in the tower low water level, water level detection sensor gave a high microcontroller, microcontroller-driven pump to add water and display system so that the red light lit; pump add water when the water level within the normal range, the green light, when the water level in the high-water mark, The microcontroller can not drive the water pump to add water, the yellow light. Light alarm circuit, the relay control circuit it works: When the water level in the low water, low water level detection sensor line is not +5 V power supply guide pass into the regulator circuit is treated in the output of the voltage regulator circuit has a high level, into the P1.0 port of the microcontroller, another high voltage circuit output of the microcontroller P1.1 port SCM After analysis, the P1.2 port outputs a low red light, drive, P1. 5 out a signal so that the optocoupler GDOUHE guide through so that the relay is closed, so that the water pump to add water; when the water level in the normal range, water pump plus P1.3 pin to a low level, so that the green light; when the water level in the high-water zone, the sensor of the two detection lines are conduction, are +5 power conduction into the SCM, SCM After analysis, the P1.4 pin out of a low yellow light, The optocoupler guide a low out of the P1.5-side can not pass, so that the relay can not be closed, the pump can not add water; failure when three flashing light indicates the system.译文水位控制电路设计中国水之源总量居世界第六位，人均占有水资源量仅为世界人均占有量的四分之一，并且在地域上分布很不平衡，长江以北的广大地区，特别是北方大、中城市大部分地区处于缺水状态，水资源短缺已成为制约我国经济发展的一个重要因素。
毕业设计外文文献翻译(原文+译文)
Environmental problems caused by Istanbul subway excavation and suggestionsfor remediation伊斯坦布尔地铁开挖引起的环境问题及补救建议Ibrahim Ocak Abstract：Many environmental problems caused by subway excavations have inevitably become an important point in city life. These problems can be categorized as transporting and stocking of excavated material, traffic jams, noise, vibrations, piles of dust mud and lack of supplies. Although these problems cause many difficulties,the most pressing for a big city like Istanbul is excava tion,since other listed difficulties result from it. Moreover, these problems are environmentally and regionally restricted to the period over which construction projects are underway and disappear when construction is finished. Currently, in Istanbul, there are nine subway construction projects in operation, covering approximately 73 km in length; over 200 km to be constructed in the near future. The amount of material excavated from ongoing construction projects covers approximately 12 million m3. In this study, problems—primarily, the problem with excavation waste(EW)—caused by subway excavation are analyzed and suggestions for remediation are offered.摘要：许多地铁开挖引起的环境问题不可避免地成为城市生活的重要部分。
外文参考文献译文及原文
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城建学部专业土木工程年级 2011级班级名称 11土木工程9班学号 23031109000学生姓名刘林指导教师卢集富2015 年5 月目录一、项目成本管理与控制 0二、Project Budget Monitor and Control (1)三、施工阶段承包商在控制施工成本方面所扮演的作用 (2)四、The Contractor's Role in Building Cost Reduction After Design (4)一、外文文献译文（1）项目成本管理与控制随着市场竞争的激烈性越来越大，在每一个项目中，进行成本控制越发重要。
本文论述了在施工阶段，项目经理如何成功地控制项目预算成本。
本文讨论了很多方法。
它表明，要取得成功，项目经理必须关注这些成功的方法。
1.简介调查显示，大多数项目会碰到超出预算的问……功控制预算成本。
2.项目控制和监测的概念和目的Erel and Raz (2000)指出项目控制周期包括测量成……原因以及决定纠偏措施并采取行动。
监控的目的就是纠偏措施的...标范围内。
3.建立一个有效的控制体系为了实现预算成本的目标，项目管理者需要建立一……被监测和控制是非常有帮助的。
项目成功与良好的沟通密...决( Diallo and Thuillier, 2005)。
4.成本费用的检测和控制4.1对检测的优先顺序进行排序在施工阶段，很多施工活动是基于原来的计……用完了。
第四，项目管理者应该检测高风险活动，高风险活动最有...重要(Cotterell and Hughes, 1995)。
4.2成本控制的方法一个项目的主要费用包括员工成本、材料成本以及工期延误的成本。
为了控制这些成本费用，项目管理者首先应该建立一个成本控制系统：a)为财务数据的管理和分析工作落实责任人员b)确保按照项目的结构来合理分配所有的……它的变化--在成本控制线上准确地记录所有恰...围、变更、进度、质量）相结合由于一个工程项目......虑时间价值影响后的结果。
外文文献原稿和译文格式
四、外文文献原稿和译文打印格式
外文文献原稿和译文包括题目、原稿、译文三个部分。
●题目为“外文文献原稿和译文”：之上之下各留一空行，宋体，三号字，居中，加粗
原稿整体格式要尽量保持与原文格式相同，如原稿格式不明确可采用如下格式：
“原稿”：之下留一空行，宋体，小三号字，居中，加粗，“原稿”二字中间空两格；原稿内容：章节题目——新罗马“Times New Roman”字体，四号字，加粗，左对齐；正文——新罗马“Times New Roman”字体，小四号字，段落设置为：固定值，22磅，段前、段后均为0磅。
“译文”：本部分另起一页。
之上之下各留一空行。
宋体，小三号字，居中，加粗。
“译文”二字中间空两格。
译文内容：章节题目——章节题目：宋体，四号字，加粗，左对齐；正文——宋体，小四号字。
段落设置为：固定值，22磅，段前、段后均为0磅。
●页面设置为：上3.5cm，下2.6cm，左2.7cm，右2.7cm，页眉2.4cm，页脚2cm。
●页眉：“北京化工大学北方学院毕业设计（论文）——外文文献原稿和译文”，宋体，小五号字，居中。
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外文文献原稿和译文原稿Mechanical and Regenerative Braking Integration for a HybridElectric VehicleAbstractHybrid electric vehicle technology has become a preferred method for the automotive industry to reduce environmental impact and fuel consumption of their vehicles. Hybrid electric vehicles accomplish these reductions through the use of multiple propulsion systems, namely an electric motor and internal combustion engine, which allow the elimination of idling, operation of the internal combustion engine in a more efficient manner and the use of regenerative braking. However, the added cost of the hybrid electric system has hindered the sales of these vehicles.A more cost effective design of an electro-hydraulic braking system is presented. The system electro-mechanically controlled the boost force created by the brake booster independently of the driver braking force and with adequate time response. The system allowed for the blending of the mechanical and regenerative braking torques in a manner transparent to the driver and allowed for regenerative braking to be conducted efficiently.A systematic design process was followed, with emphasis placed on demonstrating conceptual design feasibility and preliminary designfunctionality using virtual and physical prototyping. The virtual and physical prototypes were then used in combination as a powerful tool to validate and develop the system. The role of prototyping in the design process is presented and discussed.Through the experiences gained by the author during the design process, it is recommended that students create physical prototypes to enhance their educational experience. These experiences are evident throughout the thesis presented.1.1 Modern Hybrid Electric VehiclesWith rising gas prices and the overwhelming concern for the environment, consumers and the government have forced the automotive industry to start producing more fuel efficient vehicles with less environmental impact. One promising method that is currently being implemented is the hybrid electric vehicle.Hybrid vehicles are defined as vehicles that have two or more power sources [25]. There are a large number of possible variations, but the most common layout of hybrid vehicles today combines the power of an internal combustion engine (ICE) with the power of an electric motor and energy storage system (ESS). These vehicles are often referred to as hybrid electric vehicles (HEV’s) [25]. These two power sources are used in conjunction to optimize the efficiency and performance of the vehicle, which in turn will increase fuel economy and reduce vehicle emissions, all while delivering the performance the consumer requires. In 1997, the Toyota Prius became the first hybrid vehicle introduced into mass production in Japan. It took another three years for the first mass produced hybrid vehicle, the Honda Insight, to be introduced into the North American market. The release of the Honda Insight was closely followed by the release of the Toyota Prius in North America a couple of months later [35].Hybrid electric vehicles have the distinct advantage of regenerative braking. The electric motor, normally used for propulsion, can be usedas a generator to convert kinetic energy of the vehicle back into electrical energy during braking, rather than wasting energy as heat. This electrical energy can then be stored in an ESS (e.g. batteries or ultracapacitors) and later released to propel the vehicle using the electric motor.This process becomes even more important when considering the energy density of batteries compared to gasoline or diesel fuel. Energy density is defined as the amount of energy stored in a system per unit volume or mass [44]. To illustrate this point, 4 kilograms (4.5 litres) of gasoline will typically give a motor vehicle a range of 50 kilometres. To store the same amount of useful electric energy it requires a lead acid battery with a mass of about 270 kilograms [25]. This demonstrates the need for efficient regenerative braking to store electrical energy during driving, which in turn will keep the mass of the energy storage system down and improve the performance and efficiency of the HEV.1.2 Research Scope - Regenerative Braking SystemsThe scope of the research presented is to create a low cost regenerative braking system to be used on future economical hybrid vehicles to study the interaction between regenerative and mechanical braking of the system. This system should be able to control the combination of both regenerative and mechanical braking torque depending on driver demand and should be able to do so smoothly and safely. Controlling the regenerative braking torque can be done using control algorithms and vector control for induction motors. However, controlling the mechanical braking torque independently of the driver pedal force, while maintaining proper safety back-ups, proved to be more of a challenge. To overcome this problem, a system was developed that would attenuate the pressure in the brake booster in order to control the amount of mechanical torque developed by the braking system．2.1 Hybrid Electric Vehicle OverviewHybrid vehicles have emerged as one of the short term solutions for reducing vehicle emissions and improving fuel economy. Over the past 10 years almost all of the major automotive companies have developed and released for sale their own hybrid electric vehicles to the public. The popularity of hybrid electric vehicles has grown considerably since the turn of the century. With enormous pressure to become more environmentally friendly and with unpredictable gas prices, the sales of hybrid electric vehicles have increased dramatically in recent years.2.1.1 Hybrid ConfigurationsFor the past 100 years the objective of the hybrid has been to extend the range of electric vehicles and to overcome the problem of long recharging times [35]. There are three predominant hybrid electric vehicle configurations currently on the market today. These configurations are known as series hybrids, parallel hybrids and series/parallel hybrids.Each configuration has its advantages and disadvantages which will be discussed in the following sections.Series HybridsIn series hybrids the mechanical output from the internal combustion engine is used to drive a generator which produces electrical power that can be stored in the batteries or used to power an electric motor and drive the wheels. There is no direct mechanical connection between the engine and the driven wheels. Series hybrids tend to be used in high power systems such as large trucks or locomotives but can also be used for lower power passenger vehicles [18]. The mechanically generated electrical power is combined with the power from the battery in an electronic controller. This controller then compares the driver demand with the vehicle speed and available torque from the electric motor to determine the amount of power required from each source to drive the vehicle. During braking, the controller also switches the power electronics to regenerative mode, and directs the power being regenerated to the batteries [55].There are many advantages made possible by the arrangement describedabove. It is possible to run the ICE constantly at its most efficient operating point and share its electrical output between charging the battery and driving the electric motor. By operating the engine at its most efficient operating point, emissions can be greatly reduced and the most electrical power can be generated per volume of fuel. This configuration is also easierto implement into a vehicle because it is less complex which makes this method more cost effective.Parallel HybridsIn parallel hybrid configurations the mechanical energy output from the ICE is transmitted to a gearbox. In this gearbox the energy from the ICE can be mechanically combined with a second drive from an electric motor. The combined mechanical output is then used to drive the wheels [35]. In this configuration there is a direct connection between the engine and the driven wheels. As in series hybrids the controller compares the driver demand with the vehicle speed and output torque and determines the amount of power to be used from each source to meet the demand, while obtaining the best possible efficiency. A parallel hybrid also controls regenerative braking similarly to a series hybrid. Parallel hybrids are usually used in lower power electric vehicles in which both drives can be operated in parallel to provide higher performance [18].There are a number of advantages of a parallel hybrid over a series hybrid. The most important advantage is that since only one conversion between electrical and mechanical power is made, efficiency will be much better than the series hybrid in which two conversions are required. Since the parallel hybrid has the ability to combine both the engine and electric motor powers simultaneously, smaller electric motors can be used without sacrificing performance, while getting the fuel consumption and emission reduction benefits. Lastly, parallel hybrids only need to operate the engine when the vehicle is moving and do not need a second generator tocharge the batteries.Series/Parallel HybridsCombined hybrids have the features of both series and parallel configurations. They use a power split device to drive the wheels using dual sources of power (e.g. electric motor only, ICE only or a combination of both). While the added benefits of both series hybrids and parallel hybrids are achieved for this configuration, control algorithms become very complex because of the large number of driving possibilities available.2.1.2 Degree of HybridizationSince most HEV’s on the road today are either parallel or series/parallel, it is useful to define a variable called the ‘degree of hybridization’ to quantify the electrical power potential of these vehicles.iceem em P P P DOH += The degree of hybridization ranges from (DOH = 0) for a conventional vehicle to (DOH = 1) for an all electric vehicle [25]. As the degree of hybridization increases, a smaller ICE can be used and operated closer to its optimum efficiency for a greater proportion of the time, which will decrease fuel consumption and emissions. The electric motor power is denoted by Pem and the internal combustion engine power is denoted by Pice. Micro HybridMicro hybrids have the smallest degree of hybridization and usually consist of an integrated starter generator (ISG) connected to the engine crankshaft. The ISG allows the engine to be shut off during braking and idling to conserve fuel and then spins the crankshaft up to speed before fuel is injected during acceleration. The ISG also provides small amounts of assist to the ICE during acceleration and acts as a generator to charge the batteries during braking. Micro hybrids usually improve fuel economy by about 10 percent compared with non hybrids [53].Mild HybridMild hybrids have a similar architecture to the micro hybrid exceptthat the ISG is uprated in power to typically greater than 20 kW. However,the energy storage system is limited to less than 1 kWh [35]. Mild hybrids usually have a very short electric-only range capability but can provide a greater assist to the ICE during accelerations. The electrical components in a mild hybrid are more complex than a micro hybrid and playa greater role in the vehicle operation. Fuel economy can be improved by20 to 25 percent with a mild hybrid over non hybrid vehicles [53]. Full HybridFull hybrids do away with the ISG and replace it with a separate electric motor and alternator/starter that perform the same function. The electric motor has the ability to propel the vehicle alone, particularly in city (stop and go) driving. The energy storage system is upgraded to improve electric-only range capability and the engine is usually downsized to improve fuel economy and emissions. Full hybrids can achieve40 to 45 percent fuel consumption reductions over non hybrids [53]. Plug-in HybridPlug-in hybrids are very similar to full hybrids except that they have a much larger ESS that can be connected to an outside electrical utility source for charging. These vehicles use only the electric motor to propel the vehicle within the range of the batteries and then operate like full hybrids once the batteries have discharged to a predefined level.2.1.3 Fundamentals of Regenerative BrakingOne of the most important features of HEV’s is their ability to recover significant amounts of braking energy. The electric motors can be controlled to operate as generators during braking to convert the kinetic energy of the vehicle into electrical energy that can be stored in the energy storage system and reused. However, the braking performance of a vehicle also greatly affects vehicle safety. In an emergency braking situation the vehicle must be stopped in the shortest possible distance and must be able to maintain control over the vehicle’s direction. The latter requires control of brake force distribution to the wheels [12].Generally, the braking torque required is much larger than the torque that an electric motor can produce [12]. Therefore, a mechanical friction braking system must coexist with the electrical regenerative braking. This coexistence demands proper design and control of both mechanical and electrical braking systems to ensure smooth, stable braking operations that will not adversely affect vehicle safety.Energy Consumption in BrakingBraking a 1500 kg vehicle from 100 km/h to 0 km/h consumes about 0.16 kWh of energy based on Equation 2.2.221mv E If 25 percent of this energy could be recovered through regenerative braking techniques, then Equation 2.2 can be used to estimate that this energy could be used to accelerate the vehicle from 0 km/h to about 50 km/h, neglecting aerodynamic drag, mechanical friction and rolling resistance during both braking and accelerating. This also assumes that the generating and driving modes of the electric motor are 100% efficient. This suggests that the fuel economy of HEV’s can be greatly increased when driving in urban centres where the driver is constantly braking and accelerating. Note that the amount of energy recovered is limited by the size of the electric motor and the rate of which energy can be transferred to the ESS.2.1.4 Methods of Regenerative BrakingThere are two basic regenerative braking methods used today. These methods are often referred to as parallel regenerative braking and series regenerative braking. Each of these braking strategies have advantages and disadvantages that will be discussed in this section.Parallel Regenerative BrakingDuring parallel regenerative braking, both the electric motor and mechanical braking system always work in parallel (together) to slow the vehicle down [48]. Since mechanical braking cannot be controlled independently of the brake pedal force it is converting some of thevehicle’s kinetic energy into heat instead of electrical energy. This is not the most efficient regenerative braking method. However, parallel regenerative braking does have the advantages of being simple and cost effective. For this method to be used, the mechanical braking system needs little modification and the control algorithms for the electric motor can be easily implemented into the vehicle. This method also has the added advantage of always having the mechanical braking system as a back-up in case of a failure of the regenerative braking system.Series Regenerative BrakingDuring series regenerative braking the electric motor is solely used for braking. It is only when the motor or energy storage system can no longer accept more energy that the mechanical brakes are used [48]. This method requires that the mechanical braking torque be controlled independently of the brake pedal force and has the advantage of being the most efficient by converting as much of the vehicle’s kinetic energy into electrical energy . The downfall of this method is that it brings many costs and complexities into the system. For this method to function properly a brake-by-wire system has to be developed which either uses an electro-hydraulic brake (EHB) or an electro-mechanical brake (EMB). Both of these types of brakes require brake pedal simulators and redesigned brake systems which can become costly. Since these systems are brake-by-wire there are also many redundancies required with sensors, processors and wiring for safety which add to the complexity of the system.2.1.5 Current Regenerative Braking SystemsThe cur rent regenerative braking system in most HEV’s (e.g. Toyota Prius) is the more costly electro-hydraulic braking (EHB) system. This system uses a brake pedal simulator, which is separate from the hydraulic braking circuit, to establish driver braking demand. The braking demand is then proportioned into a regenerative and mechanical braking demand. The mechanical braking demand is then sent to a system that contains a high pressure hydraulic pump, accumulator and proportional control valves.The proportional control valves allow the brake line fluid to flow to each wheel at predefined pressures determined by the braking demand.译文混合动力电动汽车机械和再生制动的整合摘要为了减少对环境的污染和车辆的燃油消耗，混合动力电动汽车已经成为汽车工业的首选方法。