毕业设计翻译
毕业设计外文翻译齿轮
Gears are vital factors in machinery. One of the first mechanism invented using gears was the clocks. In fact, a clock is little more than a train of study and research have been made on gears in recent years because of their wide use under exacting conditions. They have to transmit heavier loads and run at higher speeds than ever before. The engineers and the machinists all consider gearing the prime elementin nearly all classes of machinery.齿轮在机械中占有极为重要的作用。
第一个利用齿轮做成的机械装置确实是钟表，事实上，它只只是是用了一系列的齿轮。
关于它能够在严格的条件下的普遍利用，在齿轮上做了大量的学习和研究。
相较过去，它们此刻必需在更高的速度下传递更重的负荷。
工程师和机械操纵工人都以为齿轮在几乎所有的机械的零件中占有首要的因素。
1. Spur gearsSpur gears are used to transmit power and rotary motion between parallel shafts. The teeth are cut parallel to the axis of the shaft on which the gears are mounted. The smaller of two gears in mesh is called the pinion and the larger is customarily Designated as the gear. In most applications, the pinion is the driving element whereas the gear is the driven element.1.直齿圆柱齿轮直齿圆柱齿轮用于平行轴之间传递力和回转运动，轮齿被切制成与安装齿轮的轴之轴线相平行。
毕业论文(设计)外文文献翻译及原文
金融体制、融资约束与投资——来自OECD的实证分析R．SemenovDepartment of Economics，University of Nijmegen，Nijmegen（荷兰内梅亨大学，经济学院）这篇论文考查了OECD的11个国家中现金流量对企业投资的影响.我们发现不同国家之间投资对企业内部可获取资金的敏感性具有显著差异,并且银企之间具有明显的紧密关系的国家的敏感性比银企之间具有公平关系的国家的低.同时，我们发现融资约束与整体金融发展指标不存在关系.我们的结论与资本市场信息和激励问题对企业投资具有重要作用这种观点一致，并且紧密的银企关系会减少这些问题从而增加企业获取外部融资的渠道。
一、引言各个国家的企业在显著不同的金融体制下运行。
金融发展水平的差别(例如，相对GDP的信用额度和相对GDP的相应股票市场的资本化程度），在所有者和管理者关系、企业和债权人的模式中，企业控制的市场活动水平可以很好地被记录.在完美资本市场,对于具有正的净现值投资机会的企业将一直获得资金。
然而，经济理论表明市场摩擦，诸如信息不对称和激励问题会使获得外部资本更加昂贵，并且具有盈利投资机会的企业不一定能够获取所需资本.这表明融资要素，例如内部产生资金数量、新债务和权益的可得性，共同决定了企业的投资决策.现今已经有大量考查外部资金可得性对投资决策的影响的实证资料（可参考，例如Fazzari（1998）、 Hoshi(1991)、 Chapman（1996）、Samuel(1998））.大多数研究结果表明金融变量例如现金流量有助于解释企业的投资水平。
这项研究结果解释表明企业投资受限于外部资金的可得性。
很多模型强调运行正常的金融中介和金融市场有助于改善信息不对称和交易成本，减缓不对称问题,从而促使储蓄资金投着长期和高回报的项目,并且提高资源的有效配置（参看Levine（1997)的评论文章）。
因而我们预期用于更加发达的金融体制的国家的企业将更容易获得外部融资.几位学者已经指出建立企业和金融中介机构可进一步缓解金融市场摩擦。
毕业设计外文翻译译文
1 工程概论1.1 工程专业1.2 工业和技术1.3 现代制造业工程专业1 工程行业是历史上最古老的行业之一。
如果没有在广阔工程领域中应用的那些技术，我们现在的文明绝不会前进。
第一位把岩石凿削成箭和矛的工具匠是现代机械工程师的鼻祖。
那些发现地球上的金属并找到冶炼和使用金属的方法的工匠们是采矿和冶金工程师的先祖。
那些发明了灌溉系统并建造了远古世纪非凡的建筑物的技师是他们那个时代的土木工程师。
2 工程一般被定义为理论科学的实际应用，例如物理和数学。
许多早期的工程设计分支不是基于科学而是经验信息，这些经验信息取决于观察和经历，而不是理论知识。
这是一个倾斜面实际应用的例子，虽然这个概念没有被确切的理解，但是它可以被量化或者数字化的表达出来。
3 从16、17世纪当代初期，量化就已经成为科学知识大爆炸的首要原因之一。
另外一个重要因素是实验法验证理论的发展。
量化包含了把来源于实验的数据和信息转变成确切的数学术语。
这更加强调了数学是现代工程学的语言。
4 从19世纪开始，它的结果的实际而科学的应用已经逐步上升。
机械工程师现在有精确的能力去计算来源于许多不同机构之间错综复杂的相互作用的机械优势。
他拥有能一起工作的既新型又强硬的材料和巨大的新能源。
工业革命开始于使用水和蒸汽一起工作。
从此使用电、汽油和其他能源作动力的机器变得如此广泛以至于它们承担了世界上很大比例的工作。
5 科学知识迅速膨胀的结果之一就是科学和工程专业的数量的增加。
到19世纪末不仅机械、土木、矿业、冶金工程被建立而且更新的化学和电气工程专业出现了。
这种膨胀现象一直持续到现在。
我们现在拥有了核能、石油、航天航空空间以及电气工程等。
每种工程领域之内都有细分。
6 例如，土木工程自身领域之内有如下细分：涉及永久性结构的建筑工程、涉及水或其他液体流动与控制系统的水利工程、涉及供水、净化、排水系统的研究的环境工程。
机械工程主要的细分是工业工程，它涉及的是错综复杂的机械系统，这些系统是工业上的，而非单独的机器。
毕业设计论文外文文献翻译
毕业设计(论文）外文文献翻译院系：财务与会计学院年级专业：201＊级财务管理姓名:学号：132148*＊*附件: 财务风险管理【Abstract】Although financial risk has increased significantly in recent years risk and risk management are not contemporary issues。
The result of increasingly global markets is that risk may originate with events thousands of miles away that have nothing to do with the domestic market。
Information is available instantaneously which means that change and subsequent market reactions occur very quickly。
The economic climate and markets can be affected very quickly by changes in exchange rates interest rates and commodity prices。
Counterparties can rapidly become problematic。
As a result it is important to ensure financial risks are identified and managed appropriately. Preparation is a key component of risk management。
【Key Words】Financial risk，Risk management，YieldsI. Financial risks arising1.1What Is Risk1.1.1The concept of riskRisk provides the basis for opportunity. The terms risk and exposure have subtle differences in their meaning. Risk refers to the probability of loss while exposure is the possibility of loss although they are often used interchangeably。
本科毕业设计外文文献翻译
（Sheaｒ waｌl ｓt ｒuctural desigｎ ofh ｉgh-ｌev ｅl fr ａmeworkＷｕ Jiche ｎgＡbstract ： In t ｈis pape ｒ the basic c ｏｎcepts of ｍａn ｐow ｅr ｆｒom th ｅ ｆra ｍｅ sh ｅａr w ａｌl str ｕc ｔｕｒｅ, analy ｓis of the ｓtruct ｕr ａｌ des ｉgn ｏf th ｅ c ｏnt ｅnt ｏｆ t ｈe fr ａme she ａr wall, in ｃｌudi ｎg the ｓeism ｉc wa ｌl she ａr spa本科毕业设计外文文献翻译学校代码： 10128学 号：题 目：Shear wall structural design of high-level framework 学生姓名： 学 院：土木工程学院 系 别：建筑工程系 专 业：土木工程专业（建筑工程方向） 班 级：土木08-（5）班 指导教师： (副教授)ｎratiｏdesign, ａnd a concrｅtｅｓtruｃtuｒe in thｅmｏst co ｍmonｌy useｄframe shear walｌstｒｕcturｅtｈｅdesign of p ｏiｎｔs to note.Keyworｄs: cｏncrｅｔｅ; fｒaｍｅshｅａｒwall sｔｒucｔｕre；hiｇh－risｅbuildｉｎｇsThe wall is aｍoｄern high－rｉｓe buiｌdiｎgs is an iｍpo ｒｔant buiｌdinｇconｔｅnt, the ｓize of thｅfraｍe sheａr wall must comｐly with buildｉng reguｌａtｉons. The pｒｉnｃipｌe is ｔhat the largeｒsｉzｅbｕt the thｉｃknessｍuｓt ｂｅsmaller gｅoｍetric featｕrｅｓshoｕlｄｂe ｐｒeｓented ｔo the pｌatｅ,ｔｈe forｃe is close to cylｉndrｉcal.Ｔhe waｌl sｈｅar wa ｌl strｕｃｔure ｉs a flaｔcomｐonent. Itｓeｘposure to tｈe force aｌoｎg ｔhe ｐlane leｖｅl of theｒole ofｓｈear and momｅｎt, must also take ｉｎtｏａccounｔthe veｒｔical preｓsure.Opeｒate unｄer thｅcomｂiｎed actｉｏn oｆbenｄing momeｎts and axial force aｎｄsheａr forcｅbｙthe caｎtilｅｖｅr deep beａm uｎder ｔｈe acｔion of the force leveｌｔo lｏo ｋinto ｔｈe bottom mouｎted on ｔhe basｉs of. Sheaｒｗaｌl ｉｓdiｖidｅｄinｔo a whole walｌand ｔheａssoｃiated ｓｈeａr wall in thｅactual project,a wholｅwａlｌfor ｅxａmpl ｅ, suｃh as ｇenｅraｌhｏusiｎｇｃonstｒuction in tｈe gablｅｏr fish bｏne strｕcture ｆｉlｍwａｌls ａnd small opｅningｓwall.Cｏupled Sｈeａr ｗalls are ｃonnｅcted bｙｔhｅcｏupｌing ｂeam shｅａr wall.Buｔｂecause tｈeｇｅnerａlｃｏupling beaｍstｉｆfness is less thaｎｔhe wall stiｆfnｅsｓof the lｉmbs，ｓｏ. Wａlｌliｍb aｌonｅis obviｏus.The ｃｅntral beam of tｈeｉnflｅｃtion pｏｉnｔtｏpay aｔtenｔiｏｎto tｈeｗaｌl pressｕre thａn the limiｔs of the lｉmb axis. Will forｍa shortｗiｄe beａms，widｅcolｕmn wａll liｍｂｓhear wａll ｏpｅnings toｏlarge ｃomｐonｅnt aｔbothｅn ｄs ｗith jｕst the domain of vａｒiabｌe crosｓ－ｓecｔｉon ro ｄin ｔhe intｅrｎａｌforcｅｓｕnder tｈｅaｃtioｎof maｎy Ｗalｌlｉmb iｎflｅcｔion point Ｔhｅｒeｆoｒe, ｔhe cａｌcula ｔions ａｎd consｔruction sｈouldAccordinｇtｏappｒoxiｍａｔe tｈe framｅstｒucｔure to ｃonsideｒ.Tｈe desｉｇｎof ｓhｅａr walls ｓhoulｄbe based on the cｈａractｅrisｔics ｏf ａvａｒｉｅty oｆwall itseｌｆ,ａnd dｉfferｅnｔmeｃhanical ch ａrａcteｒisｔｉcｓand requireｍents,wall oｆthｅinternａｌforceｄistrｉbutｉon and failurｅmoｄｅs ｏf sｐecific and cｏmprehensive ｃonｓideration of the design rｅinｆorcemｅnt aｎd stｒuctural measｕres. Ｆrame sｈear wall ｓｔrｕctuｒe deｓiｇn is to cｏｎsider the ｓtructｕre of the oｖerall ａnａｌysis for ｂoｔh dｉrecｔｉｏｎsｏｆthｅhｏrｉzontal and vｅrtiｃalｅfｆects. Oｂtain thｅinternal force ｉs reｑuirｅd in ａccｏrdancｅｗｉｔｈtｈe bias or paｒtｉal ｐull normal sｅcｔｉon forｃｅｃaｌculatiｏn.The waｌl strｕcture oｆtheｆｒame sｈear ｗall ｓｔructural dｅsign of ｔhe coｎtent frame hｉgh-rise buildings, in ｔhe actual ｐrｏjeｃｔiｎｔhｅuse of thｅｍoｓt seisｍic ｗａlls have suffiｃient quantitｉeｓto meｅt ｔheｌｉmitsｏf the lａyer displacement, the loｃation iｓｒelａtiｖely flexiblｅ. Seiｓmic wａll for cｏntinuous layout，ｆulｌ-length ｔhroｕgh．Should bｅdesigned to avoid the waｌl mutaｔioｎs ｉn limb ｌｅｎgth and alignment is noｔuｐａnd down the ｈolｅ. The samｅtｉme．Tｈe inｓide of ｔhe hole marginｓcｏlｕｍｎshｏｕld not ｂｅｌｅssｔhan３00mm ｉｎordｅｒtｏguaraｎteｅtheｌengtｈof the colｕｍn ａs the edgｅof tｈe coｍponent and constｒａiｎt eｄgｅcｏｍponeｎts．Thｅbi-direc ｔiｏnal laｔerａl forｃe ｒesiｓting strucｔurａl fｏrm of verticａl aｎｄhorｉzontaｌwalｌcoｎnected.Eａｃh ｏｔhｅr as ｔhe ａffiｎiｔｙof the shｅar wall. Ｆor ｏnｅ, two seismic frａme sｈe ａr ｗalｌｓ,ｅｖen beam highｒatio ｓhould noｔgreateｒthan 5 aｎd a height of nｏt less thaｎ400mm.Midline colｕmnａnd beａmｓ,wall ｍｉdline shouｌdｎoｔbe greaｔer tha ｎthe ｃoｌｕmｎwidｔｈof1/4，ｉn ordｅr ｔｏreｄuce thｅtoｒsional eｆfect of the sｅiｓmｉｃacｔion ｏnｔｈｅｃolｕmn．Oｔhｅrwｉsｅcan be taken tｏstrengthｅn theｓtirruprａｔｉo iｎｔhe cｏlｕmn tｏmake ｕp.If thｅshear wａｌl sheａｒsｐａn ｔhａnｔhe ｂig twｏ. Ｅveｎthe beａｍcro ｓs-heｉｇht ratiｏgreateｒthan 2.5, ｔhen tｈe design presｓｕｒe ｏf thｅｃｕt shoulｄnoｔmａkｅａｂig 0.2. Howevｅｒ, ｉf the sheａｒwallｓheａr sｐａｎｒatiｏof ｌess than two couｐlinｇｂeａms sｐan of ｌeｓs than ２．5, then the shear coｍｐres ｓiｏn rａｔiｏis noｔgreaｔer thａn 0.15. Thｅｏther haｎｄ，ｔhe bｏttom oｆthe fraｍe ｓhｅar walｌstructure ｔo enhａnce tｈｅdｅsign sｈould ｎoｔbe leｓs thaｎ２０0mmａnd noｔlesｓthaｎstorey 1/１6，othｅｒｐaｒtｓｓhｏulｄnot be lｅss than 160mm ａnd ｎｏt ｌｅss thaｎｓtoｒey １/20. Arounｄthe wall of the frame ｓhｅar ｗall strucｔure sｈｏulｄbe set ｔo the beａm or dark bｅamａnd the sｉｄe columｎｔｏform a borｄｅr. Ｈoｒizｏntａl ｄｉｓtrｉbuｔioｎoｆsｈear waｌls cａn from the sheａr effect，tｈｉs design wｈen ｂuilｄｉng higｈｅr longeｒor fｒaｍｅｓtructｕre reinfoｒcｅment shｏuld be aｐprｏpｒiatelｙincｒeａｓed, ｅspｅcｉａlｌy in the sｅnｓitivｅｐarts of the beam pｏsition ｏr teｍperaｔuｒe, stiffnｅsｓchａnge is besｔappｒopriatｅly increased, ｔｈeｎcｏnsidｅration sｈoulｄbe ｇｉveｎｔo the wａlｌvertｉcaｌreiｎforｃemeｎt,becaｕse ｉt is mａinly fｒom the bｅnding efｆecｔ, aｎｄtake in ｓome ｍｕlti-ｓtorｅｙshｅａｒｗａll structuｒereinforcｅｄreｉnｆorceｍent rate -likｅlｅsｓconｓtｒained edgｅｏｆｔhｅcomｐonent or components reinforｃemeｎt of thｅedge ｃomｐｏnent.Referｅnces: [1 sad Hａyaｓhi,He Yaming. Ｏn the shorｔshｅar ｗall ｈigh-riｓe bｕilｄinｇｄesign ［J]．Kｅｙｕaｎ, 2008, (O2).高层框架剪力墙结构设计吴继成摘要: 本文从框架剪力墙结构设计的基本概念人手, 分析了框架剪力墙的构造设计内容, 包括抗震墙、剪跨比等的设计, 并出混凝土结构中最常用的框架剪力墙结构设计的注意要点。
毕业设计(论文)外文资料翻译(学生用)
毕业设计外文资料翻译学院：信息科学与工程学院专业：软件工程姓名： XXXXX学号： XXXXXXXXX外文出处： Think In Java (用外文写)附件： 1.外文资料翻译译文；2.外文原文。
附件1：外文资料翻译译文网络编程历史上的网络编程都倾向于困难、复杂，而且极易出错。
程序员必须掌握与网络有关的大量细节，有时甚至要对硬件有深刻的认识。
一般地，我们需要理解连网协议中不同的“层”（Layer）。
而且对于每个连网库，一般都包含了数量众多的函数，分别涉及信息块的连接、打包和拆包；这些块的来回运输；以及握手等等。
这是一项令人痛苦的工作。
但是，连网本身的概念并不是很难。
我们想获得位于其他地方某台机器上的信息，并把它们移到这儿；或者相反。
这与读写文件非常相似，只是文件存在于远程机器上，而且远程机器有权决定如何处理我们请求或者发送的数据。
Java最出色的一个地方就是它的“无痛苦连网”概念。
有关连网的基层细节已被尽可能地提取出去，并隐藏在JVM以及Java的本机安装系统里进行控制。
我们使用的编程模型是一个文件的模型；事实上，网络连接（一个“套接字”）已被封装到系统对象里，所以可象对其他数据流那样采用同样的方法调用。
除此以外，在我们处理另一个连网问题——同时控制多个网络连接——的时候，Java内建的多线程机制也是十分方便的。
本章将用一系列易懂的例子解释Java的连网支持。
15.1 机器的标识当然，为了分辨来自别处的一台机器，以及为了保证自己连接的是希望的那台机器，必须有一种机制能独一无二地标识出网络内的每台机器。
早期网络只解决了如何在本地网络环境中为机器提供唯一的名字。
但Java面向的是整个因特网，这要求用一种机制对来自世界各地的机器进行标识。
为达到这个目的，我们采用了IP（互联网地址）的概念。
IP以两种形式存在着：(1) 大家最熟悉的DNS（域名服务）形式。
我自己的域名是。
所以假定我在自己的域内有一台名为Opus的计算机，它的域名就可以是。
单片机基础毕业设计外文翻译
本科生毕业设计（论文）外文翻译毕业设计题目：外文题目：Fundamentals of Single-chip Microcomputer 译文题目：单片机基础学院：信息科学与工程学院专业班级：电子信息工程0802班学生姓名：指导教师：外文原文Fundamentals of Single-chip MicrocomputerDr. Dobbs MacintoshJournalAbstractT h e s i n gl e-chi p m i c r o com pu t er i s t h e cul m i na t i on of bo t h t h e d e v el opm e nt o f t h e di gi t al c om p ut e r a nd t h e i nt e gra t e d c i r c ui t a rgu a b l y t h e t ow m o st s i gn i fi c ant i nv en t i on s of t h e 20t h ce n t u r y .T h es e t o w t yp e s o f a rc hi t e c t u r e a r e fo un d i n s i n gl e-c hi p m i c r o com pu t e r.S om e e m p l o y t h e s pl i t p ro gr a m/d at a m em o r y o f t h e H a r v a rd a r ch i t e ct u r e, s ho wn i n F i g.3-5A-1, ot h er s f o l l o w t he p hi l o so ph y,w i d e l y a d a p t ed f o r ge n e r al-pu rp os e com p ut e rs and m i c r op r oc e s s o rs,of m ak i n g n o l o gi c al di s t i nc t i on be t w ee n p ro gr a m a n d d at a m em o r y a s i n t h e P r i n c et on ar c hi t e ct u r e.In ge n e r a l t er m s a si n gl e-c hi p m i cro c om put e r i s c ha r ac t e ri z ed b y t h e i n co r po r at i o n o f al l t h e u ni t s o f a c om put e r i n t o a s i n gl e d e vi c e.Keyword: Single-chip Microcomputer ROM RAM Programming Algorithm Features• Compatible with MCS-51™ Products• 4K Bytes of In-System Reprogrammable Flash Memory– Endurance: 1,000 Write/Erase Cycles• Fully Static Operation: 0 Hz to 24 MHz• Three-level Program Memory Lock• 128 x 8-bit Internal RAM• 32 Programmable I/O Lines• Two 16-bit Timer/Counters• Six Interrupt Sources• Programmable Serial Channel• Low-power Idle and Power-down ModesDescriptionThe AT89C51 is a low-power, high-performance CMOS 8-bit microcomputer with 4Kbytes of Flash programmable and erasable read only memory (PEROM). The deviceis manufactured using Atmel’s high-density nonvolatile memory technology and iscompatible with the industry-standard MCS-51 instruction set and pinout. Theon-chipFlash allows the program memory to be reprogrammed in-system or by a conventionalnonvolatile memory programmer. By combining a versatile 8-bit CPU with Flashon a monolithic chip, the Atmel AT89C51 is a powerful microcomputer which providesa highly-flexible and cost-effective solution to many embedded control applications.The AT89C51 provides the following standard features: 4Kbytes of Flash, 128 bytes of RAM, 32 I/O lines, two 16-bittimer/counters, a five vector two-level interrupt architecture,a full duplex serial port, on-chip oscillator and clock circuitry.In addition, the AT89C51 is designed with static logicfor operation down to zero frequency and supports twosoftware selectable power saving modes. The Idle Modestops the CPU while allowing the RAM, timer/counters,serial port and interrupt system to continue functioning. ThePower-down Mode saves the RAM contents but freezesthe oscillator disabling all other chip functions until the nexthardware reset.Pin ConfigurationsBlock DiagramPin DescriptionVCCSupply voltage.GNDGround.Port 0Port 0 is an 8-bit open-drain bi-directional I/O port. As anoutput port, each pin can sink eight TTL inputs. When 1sare written to port 0 pins, the pins can be used as highimpedanceinputs.Port 0 may also be configured to be the multiplexed loworderaddress/data bus during accesses to external programand data memory. In this mode P0 has internalpullups.Port 0 also receives the code bytes during Flash programming,and outputs the code bytes during programverification. External pullups are required during program verification.Port 1Port 1 is an 8-bit bi-directional I/O port with internal pullups.The Port 1 output buffers can sink/source four TTL inputs.When 1s are written to Port 1 pins they are pulled high bythe internal pullups and can be used as inputs. As inputs,Port 1 pins that are externally being pulled low will source current (IIL) because of the internal pullups.Port 1 also receives the low-order address bytes during Flash programming and verification.Port 2Port 2 is an 8-bit bi-directional I/O port with internal pullups.The Port 2 output buffers can sink/source four TTL inputs.When 1s are written to Port 2 pins they are pulled high by the internal pullups and can be used as inputs. As inputs, Port 2 pins that are externally being pulled low will source current (IIL) because of the internal pullups.Port 2 emits the high-order address byte during fetches from external program memory and during accesses to external data memory that use 16-bit addresses (MOVX @DPTR). In this application, it uses strong internal pullups when emitting 1s. During accesses to external data memory that use 8-bit addresses (MOVX @ RI), Port 2 emits the contents of the P2 Special Function Register.Port 2 also receives the high-orderaddress bits and some control signals during Flash programming and verification.Port 3Port 3 is an 8-bit bi-directional I/O port with internal pullups.The Port 3 output buffers can sink/source four TTL inputs.When 1s are written to Port 3 pins they are pulled high by the internal pullups and can be used as inputs. As inputs,Port 3 pins that are externally being pulled low will source current (IIL) because of the pullups.Port 3 also serves the functions of various special features of the AT89C51 as listed below:Port 3 also receives some control signals for Flash programmingand verification.ALE/PROGAddress Latch Enable output pulse for latching the low byte of the address during accesses to external memory. This pin is also the program pulse input (PROG) during Flash programming.In normal operation ALE is emitted at a constant rate of 1/6the oscillator frequency, and may be used for external timing or clocking purposes. Note, however, that one ALE pulse is skipped during each access to external Data Memory.If desired, ALE operation can be disabled by setting bit 0 of SFR location 8EH. With the bit set, ALE is active only during a MOVX or MOVC instruction. Otherwise, the pin is weakly pulled high. Setting the ALE-disable bit has no effect if the microcontroller is in external execution mode.PSENProgram Store Enable is the read strobe to external program memory.When theAT89C51 is executing code from external programmemory, PSEN is activated twice each machine cycle, except that two PSEN activations are skipped during each access to external data memory.EA/VPPExternal Access Enable. EA must be strapped to GND in order to enable the device to fetch code from external program memory locations starting at 0000H up to FFFFH.Note, however, that if lock bit 1 is programmed, EA will be internally latched on reset. EA should be strapped to VCC for internal program executions. This pin also receives the 12-volt programming enable voltage (VPP) during Flash programming, for parts that require 12-volt VPP.XTAL1Input to the inverting oscillator amplifier and input to the internal clock operating circuit.XTAL2Output from the inverting oscillator amplifier.Oscillator CharacteristicsXTAL1 and XTAL2 are the input and output, respectively,of an inverting amplifier which can be configured for use as an on-chip oscillator, as shown in Figure 1. Either a quartz crystal or ceramic resonator may be used. To drive the device from an external clock source, XTAL2 should be left unconnected while XTAL1 is driven as shown in Figure 2. There are no requirements on the duty cycle of the external clock signal, since the input to the internal clocking circuitry is through a divide-by-two flip-flop, but minimum and maximum voltage high and low time specifications must be observed.Idle ModeIn idle mode, the CPU puts itself to sleep while all the onchip peripherals remain active. The mode is invoked by software. The content of the on-chip RAM and all the special functions registers remain unchanged during this mode. The idle mode can be terminated by any enabled interrupt or by a hardware reset. It should be noted that when idle is terminated by a hard ware reset, the device normally resumes programexecution,from where it left off, up to two machine cycles before the internal reset algorithm takes control. On-chip hardware inhibits access to internal RAM in this event, but access to the port pins is not inhibited. To eliminate the possibility of an unexpected write to a port pin when Idle is terminated by reset, the instruction following the one that invokes Idle should not be one that writes to a port pin or to external memory.Figure 1. Oscillator ConnectionsFigure 2. External Clock Drive ConfigurationPower-down ModeIn the power-down mode, the oscillator is stopped, and the instruction that invokes power-down is the last instruction executed. The on-chip RAM and Special Function Registers retain their values until the power-down mode is terminated. The only exit from power-down is a hardware reset. Reset redefines the SFRs but does not change the on-chip RAM. The reset should not be activated before VCC is restored to its normal operating level and must be held active long enough to allow the oscillator to restart and stabilize.Program Memory Lock BitsOn the chip are three lock bits which can be left unprogrammed (U) or can be programmed (P) to obtain the additional features listed in the table below.When lock bit 1 is programmed, the logic level at the EA pin is sampled and latched during reset. If the device is powered up without a reset, the latch initializes to a random value, and holds that value until reset is activated. It is necessary that the latched value of EA be in agreement with the current logic level at that pin in order for the device to function properly.Programming the FlashThe AT89C51 is normally shipped with the on-chip Flash memory array in the erased state (that is, contents = FFH) and ready to be programmed. The programming interface accepts either a high-voltage (12-volt) or a low-voltage (VCC) program enable signal. The low-voltage programming mode provides a convenient way to program theAT89C51 inside the user’s system, while the high-voltage programming mode is compatible with conventional thirdparty Flash or EPROM programmers. The AT89C51 is shipped with either the high-voltage or low-voltage programming mode enabled. The respective top-side marking and device signature codes are listed in the following table.The AT89C51 code memory array is programmed byte-bybyte in either programming mode. To program any nonblank byte in the on-chip Flash Memory, the entire memory must be erased using the Chip Erase Mode.Programming Algorithm: Before programming the AT89C51, the address, data and control signals should be set up according to the Flash programming mode table and Figure 3 and Figure 4. To program the AT89C51, take the following steps.1. Input the desired memory location on the address lines.2. Input the appropriate data byte on the data lines.3. Activate the correct combination of control signals.4. Raise EA/VPP to 12V for the high-voltage programming mode.5. Pulse ALE/PROG once to program a byte in the Flash array or the lock bits. The byte-write cycle is self-timed and typically takes no more than 1.5 ms.Repeat steps 1 through 5, changing the address and data for the entire array or until the end of the object file is reached.Data Polling: The AT89C51 features Data Polling to indicate the end of a write cycle. During a write cycle, an attempted read of the last byte written will result in the complement of the written datum on PO.7. Once the write cycle has been completed, true data are valid on all outputs, and the next cycle may begin. Data Polling may begin any time after a write cycle has been initiated.Ready/Busy: The progress of byte programming can also be monitored by theRDY/BSY output signal. P3.4 is pulled low after ALE goes high during programming to indicate BUSY. P3.4 is pulled high again when programming is done to indicate READY.Program Verify: If lock bits LB1 and LB2 have not been programmed, the programmed code data can be read back via the address and data lines for verification. The lock bits cannot be verified directly. Verification of the lock bits is achieved by observing that their features are enabled.Chip Erase: The entire Flash array is erased electrically by using the proper combination of control signals and by holding ALE/PROG low for 10 ms. The code array is written with all “1”s. The chip erase operation must be executed before the code memory can be re-programmed.Reading the Signature Bytes: The signature bytes are read by the same procedure as a normal verification of locations 030H, 031H, and 032H, except that P3.6 and P3.7 must be pulled to a logic low. The values returned are as follows.(030H) = 1EH indicates manufactured by Atmel(031H) = 51H indicates 89C51(032H) = FFH indicates 12V programming(032H) = 05H indicates 5V programmingProgramming InterfaceEvery code byte in the Flash array can be written and the entire array can be erasedby using the appropriate combination of control signals. The write operation cycle is selftimed and once initiated, will automatically time itself to completion. All major programming vendors offer worldwide support for the Atmel microcontroller series. Please contact your local programming vendor for the appropriate software revision.外文资料翻译译文单片机基础摘要：单片机是电脑和集成电路发展的巅峰，有据可查的是它们也是20世纪最意义的两大发明。
毕业设计文献翻译完美版
《毕业设计》文献翻译院系：电子电气工程学院学号：021309208姓名：吴骁奕指导教师：曾国辉完成时间：2013/2/15文献翻译021309208 吴骁奕A Flexible LED Driver for Automotive Lighting Applications: IC Design and E xperimental Characterization一个灵活的LED驱动汽车照明应用:集成电路设计和实验特征Abstract—This letter presents a smart driver for LEDs, particularly摘要：这文章提出了一个智能驱动发光二极管，for automotive lighting applications, which avoid ringing尤其是用于避免振荡和超调现象的汽车照明应用上，and overshoot phenomena. To this aim, advanced Soft Start and为了这个目的，在芯片上集成了优化软启动和电流升降控制技术。
Current Slope Control techniques are integrated on-chip. This letter这篇文章讨论了设计于集合于高电压的互补金属氧化半导体上的驱动技术，discusses the driver design integrating in high voltage CMOStechnology, the digital circuitry for programming and electronic用于编程和电子控制单元连接的数字电路以及功率元件提高到10瓦特。
control units interfacing, and the power devices up to 10W. Experimental同时也展示了不同功率等级使用的发光二极管和与不同类型的连接时的实验特征。
洗衣机毕业设计外文翻译
Washing machinesLet’s look inside one of today’s fully automatic washing machines that use swirling water to clean the clothes. There are many types of washing machines but this Figure shows you what most of them are basically made up of.。
The reason why a washing machine like this can wash and get the water out of the clothes at the same time is because it has a double layer drum. When washing and rinsing, the pulsator spins and makes the water swirl.. To get the water out of the clothes, the inner wall f the drum spins and the water goes through the holes.These days, the “centrifugal force washing machines” are quite popular. This type of machine does not use a pulsator. Instead, the inner wall spins really quickly. When the drum spins, the dirty clothes get stuck to the wall. The water and detergent also try to escape through the holes of the wall but before they do so, they are forced to escape through the clothes. When this happens, the power of the water and detergent removes the dirt form the clothes. Another good thing about this type of machine is that clothes don’t get tangled up so you don’t have to worry about your clothes getting ripped or damaged.Next, let’s look at some different types of washing machines!Many of you probably think that the water inside washing machines goes round and round. Actually, different washing machines make water flow in different ways.Whirlpool type:This type of washing machine uses a pulsator to force the water to move like a whirlpool inside the Drum. The spinning water forces the dirt out form the clothes inside the machine. Some of the newer models of this type also make the whirlpool move up and down to make it clean clothes even better!Agitator stirring typeThis type of washing machine has something that looks like a propeller at the bottom of the tub.This Propeller spins around and stirs the water. The water then forces the dirt out from the clothes in the machine. The good thing about this type of machine is that clothes do not get tangled up and clothes get evenly washed.Drum type:This type of machine has a drum with many holes in it. There are also protrusions bumps on the wall of the drum. As the drum turns, the clothes are picked up by the protrusions. When the clothes fall down from the top of the drum through the water, the movement removes dirt from the clothes.Centrifugal force type:As we have said before, the spinning drum pushes the water and detergent out through the wall of the inner drum. The power that comes form spinning the drum is called centrifugal force., which is where the name comes from. The water is forced through the clothes and then the holes in the inner wall. After one cycle, the water is recycled back into the tank and the process starts again. This cycle is what cleans the clothes!In Japan, people first started using machines in 1930. But then the price of a washing machine was so high that most average persons could not buy one for their homes.Looking back now, there was something strange and funny on some of the first versions of the washing machine .The machine had two rollers that were used to sandwich each shirt and other clothes to squeeze the water out of them. The rollers were turned by hand, and in fact, you needed a lot of strength to turn those things! Still, people then thought it was a really neat invention! This type of water squeezer was used for almost 30 years until something new came along. The spin drier that used “centrifugal force” to get most of the water is out of the clothes.In 1953, the nozzle type washing machine was first sold in Japan. This washing machine is like the older brother of the swirling washing machine that you see today. The price of these washing machines was lower and because of this, more people bought them. The first fully automatic washing machine was introduced in 1968, and after that, washing clothes became a lot easier to do!There are a lot of different types of washing machines. What kind of washing machine do you have in your house?Fully automatic:The fully automatic machine has two drum layers that wash, rinse and remove water from clothes together. All you have to do is add detergent and put in dirty clothes and then washing machine will do the rest. There is also a new type of fully automatic washing machine that can dry clothes after they have been washed.Twin tub:This washing machine has one part that dose the washing and another part that does the squeezing. Even though it’s a hassle to take the clothes out and move them to othe r tub, the good thing is that you can wash and squeeze at the same time with one machine.Front loading:The main feature of front loaders is that they use a lot less water than other types. This is the type of Washing machine that dry cleaners use but a lot of people in western countries have this type of washing machine in their homes too.Let’s try to make the best washing machine in the world!We should already thank the scientists that invented the fully automatic washing machine because it makes washing clothes a piece of cake.Scientists are still trying really hard to find ways to make washing machines a lot handier to use for everyone. Some of the things that they are trying to do are to find better ways of making clothes clean and ways to make washing machines last longer. There are washing machines with d trying function today so you don’t even have to hang clothes after words because it dries them automatically! Amazing!Scientists are also trying to find ways to use less water and less detergent in washing machines at present. This is because that it is better to use less water for preserving the environment.What are washing machines of the future going to be like? Maybe there will be a washing machine that dries and folds your clothes after washing them, or maybe there will be one that will wash your clothes while you are still wearing them! How handy would that be! Remember, if the first washing machine was like a dream to people in the old days, all the dreams you have about washing machines of the future may come true!Now, washing machine is becoming more and more popular. We see the main classification.Washing machine can be divided into automatic type and semi-automatic type two kinds, automatic type washing machine as long as we begin our work proactively set better washing procedure, washing machine began to work until the end without manual intervention. Andsemi-automatic washing machine washing and dewatering process is divided, is also called the double barrel washing machine, a tong, one takes off a bucket, and put tong inside washing out to artificial add to take off in the barrel dehydration is handled and complete laundry process.Full-automatic washing machine in structure to take off in tong internal bucket suit, two barrels of axis, while working with the clutch to finish washing state and dehydration of the transition of the states, on the key said is automatic washing machine.Full-automatic washing machine press catharsis means to points, can be divided into bunt washer and roll barrel type two kinds of washing machine, From the electric control ways to points, can bedivided into mechanical program-controlled type and computer board controls type washing machine two kinds.The cylinder and the pulsator washing machine are now the main two kinds.Pulsator washing machine working principle is to add clothing, then open the inlet valve, choose good bibcock of water level and correct working procedures, switch on the power, closed warehouse door, and safety switch closed at water level, the public internal switch contacts are and dehydration contacts are interlinked, inlet valve electrify water, when the barrel water reaches the specified height, in air pressure under the action of water level switch inside public contacts disconnect dehydration contacts and connect washing contacts, feed valve power to stop water, motor power is switched on, motor started running, and periodically sometimes are turning, sometimes reverse, mutual alternant, driven by clutch BoLun using the same cycle are turning, inversion, with a certain speed rotating BoLun can drive inside bucket of water and clothing, clothing rotating water formed in the mutual friction and reach the purpose of laundry. When washing process is completed, drainage electromagnetic valve electrify work, drain valve is opened, inside bucket of water exudes, and linkage shaft also the clutch from washing state switch to dehydration state, when drainage is completed, atmospheric pressure drop and inside bucket of water level switch public contacts reset through dehydration contacts, drainage electromagnetic valve keep electrify state, motor driven off running electrify bucket high-speed and jilt dry clothing, laundry program after washing machine disconnect hydropower and stop. As for intermediate process of how many times, laundry to wash the length of time, by process control.Roller-type washing machine of the principle and Pulsator washing machine are basic similar. But 110mm drum machine it no clutch variable speed, but its motor is double-speed motor, so when washing machine work in washing state, program-controlled device connected motor washinglow-speed windings, motor speed slow, working on dehydration, when they connect dehydration modal high-speed windings, motor high-speed operation, this process is programmed through the device and motor to work together to finish.To sum up, the role of these two kinds of washing machine is same, but different implementation, each has his strong point, Pulsator washing machine is simulated handmade kneaded action to work, 110mm drum type washing machine is by gravity inertial function to finish our work, they realize washing and dewatering way also have different features, Pulsator washing machine to wear clothes is relatively large, but detergents degree is higher, 110mm drum machine for clothing wear small, but detergents degrees, but lower than Pulsator washing machine to save water.So far, washing machine is still towards a higher requirements development.译文：洗衣机来看一下涡流式全自动洗衣机的构造。
毕业设计(论文)外文翻译
华南理工大学广州学院本科生毕业设计（论文）翻译外文原文名Agency Cost under the Restriction of Free Cash Flow中文译名自由现金流量的限制下的代理成本学院管理学院专业班级会计学3班学生姓名陈洁玉学生学号200930191100指导教师余勍讲师填写日期2015年5月11日外文原文版出处：译文成绩：指导教师（导师组长）签名：译文：自由现金流量的限制下的代理成本摘要代理成本理论是资本结构理论的一个重要分支。
自由现金流代理成本有显着的影响。
在这两个领域相结合的研究，将有助于建立和扩大理论体系。
代理成本理论基础上，本研究首先分类自由现金流以及统计方法的特点。
此外，投资自由现金流代理成本的存在证明了模型。
自由现金流代理成本理论引入限制，分析表明，它会改变代理成本，进而将影响代理成本和资本结构之间的关系，最后，都会影响到最优资本结构点，以保持平衡。
具体地说，自由现金流增加，相应地，债务比例会降低。
关键词：资本结构，现金流，代理成本，非金钱利益1、介绍代理成本理论，金融契约理论，信号模型和新的啄食顺序理论，新的资本结构理论的主要分支。
财务con-道的理论侧重于限制股东的合同行为，解决股东和债权人之间的冲突。
信令模式和新的啄食顺序理论中心解决投资者和管理者之间的冲突。
这两种类型的冲突是在商业组织中的主要冲突。
代理成本理论认为，如何达到平衡这两种类型的冲突，资本结构是如何形成的，这是比前两次在一定程度上更多的理论更全面。
……Agency Cost under the Restriction of Free Cash FlowAbstractAgency cost theory is an important branch of capital structural theory. Free cash flow has significant impact on agency cost. The combination of research on these two fields would help to build and extend the theoretical system. Based on agency cost theory, the present study firstly categorized the characteristics of free cash flow as well as the statistical methodologies. Furthermore, the existence of investing free cash flow in agency cost was proved by a model. Then free cash flow was introduced into agency cost theory as restriction, the analysis shows that it will change agency cost, in turn, will have an impact on the relationship between agency cost and capital structure, finally, will influence the optimal capital structure point to maintain the equilibrium. Concretely, with the increasing free cash flow, correspondingly, debt proportion will decrease.Keywords:Capital Structure,Free Cash Flow,Agency Cost,Non-Pecuniary Benefit1. IntroductionAgency cost theory, financial contract theory, signaling model and new pecking order theory are the main branches of new capital structure theory. Financial con-tract theory focuses on restricting stockholders’ behavior by contract and solving the conflict between stockholders and creditors. Signaling model and new pecking order theory center on solving the conflict between investors and managers. These two types of conflict are the main conflict in business organizations. Agency cost theory considers how equilibrium is reached in both types of conflict and how capital structure is formed, which is more theory is more comprehensive than the previous two to some degree.……。
毕业设计外文翻译----燃料电池
附件2：外文原文Battery Fuel Gauges: Accurately Measuring Charge LevelAbstract: Battery fuel gauges determine the amount of charge remaining in a secondary battery and how much longer (under specific operating conditions) the battery can continue providing power. This application note discusses the challenges presented in measuring the charge remaining in a lithium-ion battery and the different methods of implementing a fuel gauge to address these challenges.IntroductionSince the advent of the mobile phone, chargeable batteries and their associated fuel-gauge indicators have become an integral part of our information and communication society. They are just as important to us now as automotive fuel gauges have been for the past 100 years. Yet, while drivers do not tolerate inaccurate fuel gauges, mobile-phone users are often expected to live with highly inaccurate, low-resolution indicators. This article discusses the various impediments to accurately measuring charge levels and describes how designers can implement accurate fuel gauging in their battery-powered applications.Lithium-Ion BatteriesLithium-ion batteries have only been in mass production since about 1997, following the resolution of various technical problems during their development. Because they offer the highest energy density with respect to volume and weight (Figure 1), they are used in systems ranging from mobile phones to electric cars.Figure 1. The energy densities of various battery types.Lithium cells also have specific characteristics that are important for determining their charge level. A lithium battery pack must include various safety mechanisms to prevent the battery from being overcharged, deeply discharged, or reverse connected. Because the highly reactive lithium can pose an explosion hazard, lithium batteries must not be exposed to high temperatures.The anode of an Li-ion battery is made from a graphite compound, and the cathode is made of metal oxides with lithium added in a way that minimizes disruption of the lattice structure. This process is called intercalation. Because lithium reacts strongly with water, lithium batteries are constructed with non-liquid electrolytes of organic lithium salts. When charging a lithium battery, the lithium atoms are ionized in the cathode and transported through the electrolyte to the anode.Battery CapacityThe most important characteristic of a battery (apart from its voltage) is its capacity (C), specified in mA-hours and defined as the maximum amount of charge the battery can deliver. Capacity is specified by the manufacturer for a particular set of conditions, but it changes constantly after the battery is manufactured.Figure 2. The influence of temperature on battery capacity.As Figure 2 illustrates, capacity is proportional to battery temperature. The upper curve shows an Li-ion battery charged with a constant-I, constant-V process at different temperatures. Note that the battery can take approximately 20% more charge at high temperatures than it can at -20°C.As shown by the lower curves in Figure 2, temperature has an even greater influence on the available charge while a battery is being discharged. The graph shows a fully charged battery discharged with two different currents down to a cut-off point of 2.5V. Both curves show a strong dependence on temperature as well as discharge current. At a given temperature and discharge rate, the capacity of a lithium cell is given by the difference between the upper and lower curves. Thus, Li-cell capacity is greatly reduced at low temperatures or by a large discharge current or by both. After discharge at high current and low temperature, a battery still has significant residual charge, which can then be discharged at a low current at the same temperature.Self-DischargeBatteries lose their charge through unwanted chemical reactions as well as impurities in the electrolyte. Typical self-discharge rates at room temperature for common battery types are shown in Table 1.Table 1. The Self-Discharge Rates of Common Battery TypesChe mistrySelf-Discharge/ MonthLead-acid4% to 6%NiCd15% to 30%NiMH30%Lithium2% to 3%Chemical reactions are thermally driven, so self-discharge is highlytemperature-dependent (Figure 3). Self-discharge can be modelled for different battery types using a parallel resistance for leakage currents.Figure 3. Self-discharge of Li-ion batteries.AgingBattery capacity declines as the number of charge and discharge cycles increases (Figure 4). This decline is quantified by the term service life, defined as the number of charge/discharge cycles a battery can provide before its capacity falls to 80% of the initial value. The service life of a typical lithium battery is between 300 and 500 charge/discharge cycles.Lithium batteries also suffer from time-related aging, which causes their capacity to fall from the moment the battery leaves the factory, regardless of usage. This effect can cause a fully charged Li-ion battery to lose 20% of its capacity per year at 25°C, and 35% at 40°C. For partially charged batteries the aging process is more gradual: for a battery with a 40% residual charge, the loss is about 4% of its capacity per year at 25°C.Figure 4. Battery aging.Discharge CurvesThe characteristic discharge curve for a battery is specified in its data sheet for specific conditions. One factor affecting battery voltage is the load current (Figure 5). Load current cannot, unfortunately, be simulated in the model by a simple source resistance, because that resistance depends on other parameters such as the battery's age and charge level.Figure 5. Battery-discharge curve.Secondary lithium cells exhibit relatively flat discharge curves in comparison with primary cells. System developers like this behaviour because the available voltage is relatively constant. However, gradual discharge makes the battery voltage independent of the battery's residual-charge level.Accurately Measuring Charge LevelTo determine the available charge in a battery, simple monitoring methods are preferred. They should consume little energy and should (ideally) allow one to deduce the charge level from battery voltage. Such a voltage-only method can produce unreliable outcomes, however, because no clear correlation exists between voltage and the available charge (Figure 5). Battery voltage also depends on temperature, and dynamic relaxation effects can cause a slow increase in the terminal voltage after a reduction in load current. Thus, purely voltage-based monitoring is unlikely to provide charge-level accuracies better than 25%.The relative charge level, often called the state of charge (SOC), is defined as the ratio of residual charge to the battery's charge capacity. Hence charge flow must be measured and monitored through a procedure called "coulomb counting." In practice, coulomb counting is accomplished by integrating the currents flowing into and out of the cell. To measure these currents with a high-resolution ADC, one typically connects a small resistor in series with the anode.Fuel-Gauge LearningThe functional relationship between battery SOC and the parameters mentioned above cannot be related analytically, so cell capacity and charge must be determined empirically. No extensive analytical models are available for calculating (with sufficient accuracy) the capacity of a battery under practical operating conditions such as temperature, number of charge cycles, current, age, etc. Theoretical models apply only to certain "local" conditions. For determining relative charge levels, they are applied locally and calibrated globally.To achieve sufficient accuracy while a battery is in use, the model parameters must be calibrated constantly through a process called fuel-gauge "learning." In conjunction with coulomb counting, that approach yields fuel gauges accurate to within a few percent.Fuel-Gauge SelectionModern integrated circuits can determine the SOC for all types of secondary cells, cell configurations, and applications. Despite their low supply current (about 60µA in active mode and 1µA in sleep mode), these ICs achieve a high degree of accuracy. Fuel-gauge ICs fall into three categories (Table 2). Because lithium-based batteries are preferred for many applications, the examples shown are based on Li-ion and Li-polymer batteries.Table 2. Fuel-Gauge Circuits.PartType ofFuel-Gauge ICFunction in Battery PackFunction in HostSystemDS27 62 Coulomb counter MeasurementAlgorithm +displayDS27 80 Fuel gaugeMeasurement +algorithmDisplayMAX 1781Programmablefuel gaugeMeasurement + flexiblealgorithmDisplayCoulomb counters, sometimes known as battery monitors, are ICs that measure, count, and convert the battery's parameters mentioned above, including charge, temperature, voltage, load cycles, and time. Because coulomb counters do not process the measured variables, they are not intelligent. One such device, the DS2762, already includes an integrated, highly accurate 25m resistor for measuring current. It monitors temperature, battery voltage, and current, and it features a 1-Wire® bus that allows all readings to be read by a microcontroller residing in the battery pack or host system. It also offers the requisite safety circuit essential for secondary Li cells. The result is a flexible,cost-effective system that requires considerable knowledge and development effort (although costs are offset by the software, models, and support provided by the IC vendor).An alternative approach to the coulomb counter is provided by fuel gauges. Theseall-in-one devices perform fuel-gauging routines with a learning algorithm, and they perform all necessary measurements on their own. Fuel gauges are typically deployed in intelligent, autonomous batteries called smart batteries. Because development effort is considerably less with integrated fuel gauges, this approach is well suited for applications that demand a quick time to market. One such fuel gauge, the DS2780, allows the host to read the SOC using the 1-Wire bus.Another option is provided by programmable fuel gauges, which include integrated microcontrollers that provide considerable flexibility. The MAX1781, for example, includes an integrated RISC core, EEPROM, and RAM. This device enables developers to implement battery models, fuel-gauging routines, and measurements as required. Integrated LED drivers support simple but accurate SOC indication.SummaryFuel gauging of chargeable battery cells is a complex task due to the many interdependent parameters that influence cell capacity. Simple methods of measurement, therefore, deliver inaccurate results that are adequate only for non-critical applications. By utilizing off-the-shelf fuel-gauge ICs, however, one can implement highly accurate and reliable fuel gauges.燃料电池,准确测量负载水平文摘:电池燃料仪检测电荷残留在废旧电池和多少时间(在特定的操作条件)电池可以继续提供电力。
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。
毕业设计英文翻译中英文对照版
Feasibility assessment of a leading-edge-flutter wind power generator前缘颤振风力发电机的可行性评估Luca Caracoglia卢卡卡拉克格里亚Department of Civil and Environmental Engineering, Northeastern University, 400 Snell Engineering Center, 360 Huntington A venue, Boston, MA 02115, USA美国东北大学土木与环境工程斯内尔工程中心400，亨廷顿大道360，波士顿02115This study addresses the preliminary technical feasibility assessment of a mechanical apparatus for conversion of wind energy. 这项研究涉及的是风能转换的机械设备的初步技术可行性评估。
The proposed device, designated as ‘‘leading-edge-fl utter wind power generator’’, employs aeroelastic dynamic instability of a blade airfoil, torsionally rotating about its leading edge. 这种被推荐的定义为“前缘颤振风力发电机”的设备，采用的气动弹性动态不稳定叶片翼型，通过尖端旋转产生扭矩。
Although the exploitation of aeroelastic phenomena has been proposed by the research community for energy harvesting, this apparatus is compact, simple and marginally susceptible to turbulence and wake effects.虽然气动弹性现象的开发已经有研究界提出可以通过能量采集。
毕业设计论文外文文献翻译
xxxx大学xxx学院毕业设计（论文）外文文献翻译系部xxxx专业xxxx学生姓名xxxx 学号xxxx指导教师xxxx 职称xxxx2013年3 月Introducing the Spring FrameworkThe Spring Framework: a popular open source application framework that addresses many of the issues outlined in this book. This chapter will introduce the basic ideas of Spring and dis-cuss the central “bean factory” lightweight Inversion-of-Control (IoC) container in detail.Spring makes it particularly easy to implement lightweight, yet extensible, J2EE archi-tectures. It provides an out-of-the-box implementation of the fundamental architectural building blocks we recommend. Spring provides a consistent way of structuring your applications, and provides numerous middle tier features that can make J2EE development significantly easier and more flexible than in traditional approaches.The basic motivations for Spring are:To address areas not well served by other frameworks. There are numerous good solutions to specific areas of J2EE infrastructure: web frameworks, persistence solutions, remoting tools, and so on. However, integrating these tools into a comprehensive architecture can involve significant effort, and can become a burden. Spring aims to provide an end-to-end solution, integrating spe-cialized frameworks into a coherent overall infrastructure. Spring also addresses some areas that other frameworks don’t. For example, few frameworks address generic transaction management, data access object implementation, and gluing all those things together into an application, while still allowing for best-of-breed choice in each area. Hence we term Spring an application framework, rather than a web framework, IoC or AOP framework, or even middle tier framework.To allow for easy adoption. A framework should be cleanly layered, allowing the use of indi-vidual features without imposing a whole worldview on the application. Many Spring features, such as the JDBC abstraction layer or Hibernate integration, can be used in a library style or as part of the Spring end-to-end solution.To deliver ease of use. As we’ve noted, J2EE out of the box is relatively hard to use to solve many common problems. A good infrastructure framework should make simple tasks simple to achieve, without forcing tradeoffs for future complex requirements (like distributed transactions) on the application developer. It should allow developers to leverage J2EE services such as JTA where appropriate, but to avoid dependence on them in cases when they are unnecessarily complex.To make it easier to apply best practices. Spring aims to reduce the cost of adhering to best practices such as programming to interfaces, rather than classes, almost to zero. However, it leaves the choice of architectural style to the developer.Non-invasiveness. Application objects should have minimal dependence on the framework. If leveraging a specific Spring feature, an object should depend only on that particular feature, whether by implementing a callback interface or using the framework as a class library. IoC and AOP are the key enabling technologies for avoiding framework dependence.Consistent configuration. A good infrastructure framework should keep application configuration flexible and consistent, avoiding the need for custom singletons and factories. A single style should be applicable to all configuration needs, from the middle tier to web controllers.Ease of testing. Testing either whole applications or individual application classes in unit tests should be as easy as possible. Replacing resources or application objects with mock objects should be straightforward.To allow for extensibility. Because Spring is itself based on interfaces, rather than classes, it is easy to extend or customize it. Many Spring components use strategy interfaces, allowing easy customization.A Layered Application FrameworkChapter 6 introduced the Spring Framework as a lightweight container, competing with IoC containers such as PicoContainer. While the Spring lightweight container for JavaBeans is a core concept, this is just the foundation for a solution for all middleware layers.Basic Building Blockspring is a full-featured application framework that can be leveraged at many levels. It consists of multi-ple sub-frameworks that are fairly independent but still integrate closely into a one-stop shop, if desired. The key areas are:Bean factory. The Spring lightweight IoC container, capable of configuring and wiring up Java-Beans and most plain Java objects, removing the need for custom singletons and ad hoc configura-tion. Various out-of-the-box implementations include an XML-based bean factory. The lightweight IoC container and its Dependency Injection capabilities will be the main focus of this chapter.Application context. A Spring application context extends the bean factory concept by adding support for message sources and resource loading, and providing hooks into existing environ-ments. Various out-of-the-box implementations include standalone application contexts and an XML-based web application context.AOP framework. The Spring AOP framework provides AOP support for method interception on any class managed by a Spring lightweight container.It supports easy proxying of beans in a bean factory, seamlessly weaving in interceptors and other advice at runtime. Chapter 8 dis-cusses the Spring AOP framework in detail. The main use of the Spring AOP framework is to provide declarative enterprise services for POJOs.Auto-proxying. Spring provides a higher level of abstraction over the AOP framework and low-level services, which offers similar ease-of-use to .NET within a J2EE context. In particular, the provision of declarative enterprise services can be driven by source-level metadata.Transaction management. Spring provides a generic transaction management infrastructure, with pluggable transaction strategies (such as JTA and JDBC) and various means for demarcat-ing transactions in applications. Chapter 9 discusses its rationale and the power and flexibility that it offers.DAO abstraction. Spring defines a set of generic data access exceptions that can be used for cre-ating generic DAO interfaces that throw meaningful exceptions independent of the underlying persistence mechanism. Chapter 10 illustrates the Spring support for DAOs in more detail, examining JDBC, JDO, and Hibernate as implementation strategies.JDBC support. Spring offers two levels of JDBC abstraction that significantly ease the effort of writing JDBC-based DAOs: the org.springframework.jdbc.core package (a template/callback approach) and the org.springframework.jdbc.object package (modeling RDBMS operations as reusable objects). Using the Spring JDBC packages can deliver much greater pro-ductivity and eliminate the potential for common errors such as leaked connections, compared with direct use of JDBC. The Spring JDBC abstraction integrates with the transaction and DAO abstractions.Integration with O/R mapping tools. Spring provides support classesfor O/R Mapping tools like Hibernate, JDO, and iBATIS Database Layer to simplify resource setup, acquisition, and release, and to integrate with the overall transaction and DAO abstractions. These integration packages allow applications to dispense with custom ThreadLocal sessions and native transac-tion handling, regardless of the underlying O/R mapping approach they work with.Web MVC framework. Spring provides a clean implementation of web MVC, consistent with the JavaBean configuration approach. The Spring web framework enables web controllers to be configured within an IoC container, eliminating the need to write any custom code to access business layer services. It provides a generic DispatcherServlet and out-of-the-box controller classes for command and form handling. Request-to-controller mapping, view resolution, locale resolution and other important services are all pluggable, making the framework highly extensi-ble. The web framework is designed to work not only with JSP, but with any view technology, such as Velocity—without the need for additional bridges. Chapter 13 discusses web tier design and the Spring web MVC framework in detail.Remoting support. Spring provides a thin abstraction layer for accessing remote services without hard-coded lookups, and for exposing Spring-managed application beans as remote services. Out-of-the-box support is inc luded for RMI, Caucho’s Hessian and Burlap web service protocols, and WSDL Web Services via JAX-RPC. Chapter 11 discusses lightweight remoting.While Spring addresses areas as diverse as transaction management and web MVC, it uses a consistent approach everywhere. Once you have learned the basic configuration style, you will be able to apply it in many areas. Resources, middle tier objects, and web components are all set up using the same bean configuration mechanism. You can combine your entireconfiguration in one single bean definition file or split it by application modules or layers; the choice is up to you as the application developer. There is no need for diverse configuration files in a variety of formats, spread out across the application.Spring on J2EEAlthough many parts of Spring can be used in any kind of Java environment, it is primarily a J2EE application framework. For example, there are convenience classes for linking JNDI resources into a bean factory, such as JDBC DataSources and EJBs, and integration with JTA for distributed transaction management. In most cases, application objects do not need to work with J2EE APIs directly, improving reusability and meaning that there is no need to write verbose, hard-to-test, JNDI lookups.Thus Spring allows application code to seamlessly integrate into a J2EE environment without being unnecessarily tied to it. You can build upon J2EE services where it makes sense for your application, and choose lighter-weight solutions if there are no complex requirements. For example, you need to use JTA as transaction strategy only if you face distributed transaction requirements. For a single database, there are alternative strategies that do not depend on a J2EE container. Switching between those transac-tion strategies is merely a matter of configuration; Spring’s consistent abstraction avoids any need to change application code.Spring offers support for accessing EJBs. This is an important feature (and relevant even in a book on “J2EE without EJB”) because the u se of dynamic proxies as codeless client-side business delegates means that Spring can make using a local stateless session EJB an implementation-level, rather than a fundamen-tal architectural, choice.Thus if you want to use EJB, you can within a consistent architecture; however, you do not need to make EJB the cornerstone of your architecture. This Spring feature can make devel-oping EJB applications significantly faster, because there is no need to write custom code in service loca-tors or business delegates. Testing EJB client code is also much easier, because it only depends on the EJB’s Business Methods interface (which is not EJB-specific), not on JNDI or the EJB API.Spring also provides support for implementing EJBs, in the form of convenience superclasses for EJB implementation classes, which load a Spring lightweight container based on an environment variable specified in the ejb-jar.xml deployment descriptor. This is a powerful and convenient way of imple-menting SLSBs or MDBs that are facades for fine-grained POJOs: a best practice if you do choose to implement an EJB application. Using this Spring feature does not conflict with EJB in any way—it merely simplifies following good practice.Introducing the Spring FrameworkThe main aim of Spring is to make J2EE easier to use and promote good programming practice. It does not reinvent the wheel; thus you’ll find no logging packages in Spring, no connection pools, no distributed transaction coordinator. All these features are provided by other open source projects—such as Jakarta Commons Logging (which Spring uses for all its log output), Jakarta Commons DBCP (which can be used as local DataSource), and ObjectWeb JOTM (which can be used as transaction manager)—or by your J2EE application server. For the same reason, Spring doesn’t provide an O/R mapping layer: There are good solutions for this problem area, such as Hibernate and JDO.Spring does aim to make existing technologies easier to use. For example, although Spring is not in the business of low-level transactioncoordination, it does provide an abstraction layer over JTA or any other transaction strategy. Spring is also popular as middle tier infrastructure for Hibernate, because it provides solutions to many common issues like SessionFactory setup, ThreadLocal sessions, and exception handling. With the Spring HibernateTemplate class, implementation methods of Hibernate DAOs can be reduced to one-liners while properly participating in transactions.The Spring Framework does not aim to replace J2EE middle tier services as a whole. It is an application framework that makes accessing low-level J2EE container ser-vices easier. Furthermore, it offers lightweight alternatives for certain J2EE services in some scenarios, such as a JDBC-based transaction strategy instead of JTA when just working with a single database. Essentially, Spring enables you to write appli-cations that scale down as well as up.Spring for Web ApplicationsA typical usage of Spring in a J2EE environment is to serve as backbone for the logical middle tier of a J2EE web application. Spring provides a web application context concept, a powerful lightweight IoC container that seamlessly adapts to a web environment: It can be accessed from any kind of web tier, whether Struts, WebWork, Tapestry, JSF, Spring web MVC, or a custom solution.The following code shows a typical example of such a web application context. In a typical Spring web app, an applicationContext.xml file will reside in the WEB-INF directory, containing bean defini-tions according to the “spring-beans” DTD. In such a bean definition XML file, business objects and resources are defined, for example, a “myDataSource” bean, a “myInventoryManager” bean, and a “myProductManager” bean. Spring takes care of their configuration, their wiring up, and their lifecycle.<beans><bean id=”myDataSource” class=”org.springframework.jdbc. datasource.DriverManagerDataSource”><property name=”driverClassName”> <value>com.mysql.jdbc.Driver</value></property> <property name=”url”><value>jdbc:mysql:myds</value></property></bean><bean id=”myInventoryManager” class=”ebusiness.DefaultInventoryManager”> <property name=”dataSource”><ref bean=”myDataSource”/> </property></bean><bean id=”myProductManager” class=”ebusiness.DefaultProductManage r”><property name=”inventoryManager”><ref bean=”myInventoryManager”/> </property><property name=”retrieveCurrentStock”> <value>true</value></property></bean></beans>By default, all such beans have “singleton” scope: one instance per context. The “myInventoryManager” bean will automatically be wired up with the defined DataSource, while “myProductManager” will in turn receive a reference to the “myInventoryManager” bean. Those objects (traditionally called “beans” in Spring terminology) need to expos e only the corresponding bean properties or constructor arguments (as you’ll see later in this chapter); they do not have to perform any custom lookups.A root web application context will be loaded by a ContextLoaderListener that is defined in web.xml as follows:<web-app><listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class></listener>...</web-app>After initialization of the web app, the root web application context will be available as a ServletContext attribute to the whole web application, in the usual manner. It can be retrieved from there easily via fetching the corresponding attribute, or via a convenience method in org.springframework.web. context.support.WebApplicationContextUtils. This means that the application context will be available in any web resource with access to the ServletContext, like a Servlet, Filter, JSP, or Struts Action, as follows:WebApplicationContext wac = WebApplicationContextUtils.getWebApplicationContext(servletContext);The Spring web MVC framework allows web controllers to be defined as JavaBeans in child application contexts, one per dispatcher servlet. Such controllers can express dependencies on beans in the root application context via simple bean references. Therefore, typical Spring web MVC applications never need to perform a manual lookup of an application context or bean factory, or do any other form of lookup.Neither do other client objects that are managed by an application context themselves: They can receive collaborating objects as bean references.The Core Bean FactoryIn the previous section, we have seen a typical usage of the Spring IoC container in a web environment: The provided convenience classes allow for seamless integration without having to worry about low-level container details. Nevertheless, it does help to look at the inner workings to understand how Spring manages the container. Therefore, we will now look at the Spring bean container in more detail, starting at the lowest building block: the bean factory. Later, we’ll continue with resource setup and details on the application context concept.One of the main incentives for a lightweight container is to dispense with the multitude of custom facto-ries and singletons often found in J2EE applications. The Spring bean factory provides one consistent way to set up any number of application objects, whether coarse-grained components or fine-grained busi-ness objects. Applying reflection and Dependency Injection, the bean factory can host components that do not need to be aware of Spring at all. Hence we call Spring a non-invasive application framework.Fundamental InterfacesThe fundamental lightweight container interface is org.springframework.beans.factory.Bean Factory. This is a simple interface, which is easy to implement directly in the unlikely case that none of the implementations provided with Spring suffices. The BeanFactory interface offers two getBean() methods for looking up bean instances by String name, with the option to check for a required type (and throw an exception if there is a type mismatch).public interface BeanFactory {Object getBean(String name) throws BeansException;Object getBean(String name, Class requiredType) throws BeansException;boolean containsBean(String name);boolean isSingleton(String name) throws NoSuchBeanDefinitionException;String[] getAliases(String name) throws NoSuchBeanDefinitionException;}The isSingleton() method allows calling code to check whether the specified name represents a sin-gleton or prototype bean definition. In the case of a singleton bean, all calls to the getBean() method will return the same object instance. In the case of a prototype bean, each call to getBean() returns an inde-pendent object instance, configured identically.The getAliases() method will return alias names defined for the given bean name, if any. This mecha-nism is used to provide more descriptive alternative names for beans than are permitted in certain bean factory storage representations, such as XML id attributes.The methods in most BeanFactory implementations are aware of a hierarchy that the implementation may be part of. If a bean is not foundin the current factory, the parent factory will be asked, up until the root factory. From the point of view of a caller, all factories in such a hierarchy will appear to be merged into one. Bean definitions in ancestor contexts are visible to descendant contexts, but not the reverse.All exceptions thrown by the BeanFactory interface and sub-interfaces extend org.springframework. beans.BeansException, and are unchecked. This reflects the fact that low-level configuration prob-lems are not usually recoverable: Hence, application developers can choose to write code to recover from such failures if they wish to, but should not be forced to write code in the majority of cases where config-uration failure is fatal.Most implementations of the BeanFactory interface do not merely provide a registry of objects by name; they provide rich support for configuring those objects using IoC. For example, they manage dependen-cies between managed objects, as well as simple properties. In the next section, we’ll look at how such configuration can be expressed in a simple and intuitive XML structure.The sub-interface org.springframework.beans.factory.ListableBeanFactory supports listing beans in a factory. It provides methods to retrieve the number of beans defined, the names of all beans, and the names of beans that are instances of a given type:public interface ListableBeanFactory extends BeanFactory {int getBeanDefinitionCount();String[] getBeanDefinitionNames();String[] getBeanDefinitionNames(Class type);boolean containsBeanDefinition(String name);Map getBeansOfType(Class type, boolean includePrototypes,boolean includeFactoryBeans) throws BeansException}The ability to obtain such information about the objects managed by a ListableBeanFactory can be used to implement objects that work with a set of other objects known only at runtime.In contrast to the BeanFactory interface, the methods in ListableBeanFactory apply to the current factory instance and do not take account of a hierarchy that the factory may be part of. The org.spring framework.beans.factory.BeanFactoryUtils class provides analogous methods that traverse an entire factory hierarchy.There are various ways to leverage a Spring bean factory, ranging from simple bean configuration to J2EE resource integration and AOP proxy generation. The bean factory is the central, consistent way of setting up any kind of application objects in Spring, whether DAOs, business objects, or web controllers. Note that application objects seldom need to work with the BeanFactory interface directly, but are usu-ally configured and wired by a factory without the need for any Spring-specific code.For standalone usage, the Spring distribution provides a tiny spring-core.jar file that can be embed-ded in any kind of application. Its only third-party dependency beyond J2SE 1.3 (plus JAXP for XML parsing) is the Jakarta Commons Logging API.The bean factory is the core of Spring and the foundation for many other services that the framework offers. Nevertheless, the bean factory can easily be used stan-dalone if no other Spring services are required.Derivative：networkSpring 框架简介Spring框架：这是一个流行的开源应用框架，它可以解决很多问题。
本科毕业设计翻译英文
( 1. Faculty of Civil Engineering & Geosciences, Delft University of Technology , P. O. Box 5048,2600 GA Delft, t he Nether lands; 2. Key Laboratory of Silicate Materials Science and Engineering of the Ministry of Education, Wuhan University of Technology, Wuhan 430070, China)Abstract: Coal tar, a by- product from the destructive distillation of coal in co king oven, is widely used in road engineering for its excellent adhesion and fuel resistance properties, especially for pavement surface treatments in gas stations and airports.However, coal tar has a high Poly cyclic Aromatic Hydro carbons ( or PAHs) content, which makes it toxic.I n 1985, the International Agency for Research on Cancer ( IARC) has proved that coal tar is carcinogenic to humans. Research showed that Coal Tar- based Sealers ( CTS) contribute to the majority of PAHs pollution in the water environment. Because of this environmental concern, CT S are not allowed in many dev eloped countries in the USA and Europe. In contrast, coal tar is still used for road engineering in China and is even used increasingly .This paper gives a literature review on the general information and research about environmental concern of using coal tar in road engineering. Based on the review , some possible alternatives to replace coal tar are described. These alternatives include nanoclay/ epoxy modified bitumen/ bitumen emulsion and waterborne polyuret hane/ epoxy resin, which are environmental friendly. They have the potential to perform as w ell as CTS, and even better in some special applications.Key words:coal tar; pavement surface treatment; adhesion property; poly cyclic aromatic hydrocarbons; modified bitumen emulsionCLC number: U 416 Document code: A Article ID: 1671- 4431( 2010) 17- 0001- 07Received date: 2010- 05- 07.Biography : Xiao Y( 1986- ) , Ph D Candidate. E-mail: yue. xiao@1 introductionTwo basic types of binders are currently used in the pavement surface treatment market: coal tar-based and bitumen-based. At some places like g as stat ions and airports, coal tar-based surface sealers performed much better than bitumen-based sealers with regards to adhesion properties and chemical resistance. Coal tar-based have better resistance to petroleum oils and inorganic acids, and have better moisture resistance[ Austin, 2005] .Because of these out standing properties, CTS are widely used in road engineering for pavement surfacetreatment for many years. However, coal tar is a complex hydrocarbon mixture consisting of hundred of PAH[SCHER, 2008] . These PAHs are toxic and considered human carcinogens. Because of it s environmental unfriendly properties, coal tar is not allowed in most of the developed counties like the Netherlands. In the Netherlands,use of tar containing product s is not allowed since 20 years, with one temporary except ion for antiskid runways in airfields [ van Leest , 2005] . But after 2010, it w ill not be allowed for airport pavement application anymore. Compared to these bans, coal tar is still used for road engineering in China. China Coal Tar Industry Report mentioned that the coal tar consumption w ill be on the upward t rend [CCTIR, 2008] .Based on new technologies like nano technology and two-component technology, other materials are developed for pavement surface treatment and they perform w ell. Modified bitumen emulsions, which can be applied at low temperatures, were successfully used in South Africa, Australia and many other countries. Additives such as polymers ( SBS, SBR and EVA ) , clays ( illite, kaolinite and montmorillonite ) are known to improve the properties of bitumen emulsions in special road applications [ TRB-EC102, 2006;Xiao, 2010] . With the waterborne two-component technology, coating manufacturers can producehigh-performance sealers and achieve the same or better properties than solvent-based sealers. Furthermore, waterborne resins for coating s usually do not contain or just contain a small amounts of other solvent s, indicating that waterborne two component systems are environmental friendly. Epoxy modified bitumen w as originally developed in the late 1950s by Shell Oil Company as a material designed to withstand fuel exposure [ Thom, 2006] . After full curing , epoxy modified bitumen mixture has high temperature stability and strength, excellent fatigue, superior adhesion and rutting resistance.In this paper, a short literature review is given on the use and properties of CTS for pavement surface treatment and its environmental concern. After that several possible alternatives are discussed, such as nanoclay modified bitumen emulsion, epoxy modified bitumen, waterborne polyurethane/ epoxy resin. These alternatives may have good properties and are environmental friendly.2 Use and Advantages of Coal Tar Based SealersCoal tar-based products are used in many industries, for example pavement engineering, the building industry and medical treatment s. In pavement engineering , one of the largest applications is CTS.Coal tar can be used as a binder and filler in surface treatment formulations, and as a modifier for epoxyresin surface coating s. T he streets of Baghdad w ere the first to be paved with tar from the 8th century AD. Tar was a vital component of the first sealed, or tarmac roads. The first tar macadam road with a tar-bound surface was placed in 1848 out side Nottingham, England. In Washington D. C. some of thetar-bound surface courses have a service life of about 30 years.Coal tar is a very complex mixture of chemicals. It s molecular structure is quite different from bitumen.Some of the constituents are described as PAHs. Being stable in molecular structure, these chemicals are incompatible with oil and gas, and provide a barrier coat to protect asphalt surfaces against the destructive effects of petroleum based products and chemicals [Aust in, 2005] . CTS have a better chemical resistance than bitumen based, extremely low permeability to moisture and a high resistance to ultraviolet radiation. These properties make it ideally suited for parking areas w here concentrations of oil and gasoline leaks are prevalent, like gas stations, truck and bus terminals and airport s. CTS are used to extend the life and reduce maintenance cost associated with asphalt pavements, primarily in asphalt road pavement. They are typically used at airports for aprons, taxiways and runways. The Federal Aviation Administration Advisory Circular 150/ 5370-10A Standards for Specifying Construction of Airports include a requirement for pavement sealers that they should contain at least 35% coal tar in runway asphalt pavement.The reason for this requirement is that CTS have a much better resistance to jet fuel than bitumen-based sealers [Austin, 2005].3 Environmental ConcernGenerally, coal tars consist of a mixture of many organic compounds, like benzene, toluene, phenol, naphthalene, anthracite , and others. The risk assessment of coal tar is largely based on PAHs, especially on Benzo (a) pyrene . PAHs are the most relevant component s in terms of toxicity in coal tarproducts[ SCHER, 2008] .3. 1 Polycyclic aromatic hydrocarbonsPolycyclic aromatic hydrocarbons are also known as polycyclic aromatic compounds, polyaromatic hydrocarbons or as polynuclear aromatics. PAHs are a group of over 100 different chemicals consisting of carbon and hydrogen in fused-ring structures. T able 1 shows several typical chemical structures of PAHs. PAHs are highly toxic and harmful to human and ecosystem health [Austin, 2005] . The content of PAHs in coal tar increases as the carbonization temperature increases.3.2 Environmental riskIn 1985, IARC has pointed out that coal tar pitches are carcinogenic in humans [IARC, 1985] . In 2008,three scientific commit tees ( SCCP, the Scientific Commit -tee on Consumer Products; SCHER, the Scientific Committee on Health and Environmental Risks; SCEN IHR, the Scientific Commit tee on Emerging and NewlyIdentified Health Risks) concluded that cancer risk was the most serious point of coal tar s risk characterizations [ SCHER, 2008] . Occupational exposure to coal tar increases the risk of developing skin cancer and other tissue sites , like lung, bladder, kidney and digestive tract . According to the IARC, products that include more than 5 percent of crude coal tar are Group 1 carcinogen which has sufficient evidence of carcinogenicity in humans. So, many countries all over the world have eliminated it s usage.In 2003, scientist s from the city of Austin ( USA ) identified CTS as a significant source of PAHs contamination. The United States Geological Survey and Austin City have conducted additional research that corroborates this finding, concluding that coal tar sealants are responsible for the majority of PAHs pollution in water environment in the Austin area. Coal tar-based pavement sealers are considered as a source of urban water pollution. These are long-lasting substances that can build up in the food chain to harmful levels to humans. Based on their investigations, Austin became the first city in the USA to ban the use of CTS for pavements [ Austin,2005; Mahler, 2005] .As a precaution, in Germany, manufacturers have voluntarily agreed to ban coal tar from their product s. In the Netherlands, coal tar containing products did not meet the Dutch Environmental Standards and w ill not be allowed for airport pavement after 2010.4 Possible AlternativesAccording to these environmental concerns, alternatives are required. These alternatives should have atleast comparable or better properties than CTS. At the same time, they should be environmental friendly. In this section, the possible use of modified bitumen emulsions, epoxy modified bitumen and waterborne resins are discussed.4. 1 Modified bitumen emulsionsBitumen emulsions are heterogeneous systems with two or more liquid phases, consisting of a continuous liquid phase ( water ) and at least one second liquid phase ( bitumen) dispersed in the former as fine droplets [ TRB-EC102, 2006] . Standard bitumen emulsions are normally considered to be of the oil in water type and contain from 40% to 75% bitumen, 0. 1% to 2. 5% emulsifier, 25% to 60% water plus some minor components. The bitumen droplets rang e from 0. 1 to 20 micron in diameter.4. 1. 1 Properties of modified bitumen emulsionsUnlike bitumen, bitumen emulsions do not need to be heated at high temperatures before application. Temperature storage and application at ambient temperature can avoid the use of energy and emissions associated with heating and drying [Kennedy, 1997]. This makes bitumen emulsions more economic and environmental friendl , compared to coal tar-based products.Additives are used to improve the properties of bitumen emulsions in special road applications. Polymer( SBS, SBR and EVA) , clay illite , kaolinite and montmorillonite and epoxy modified bitumen/ bitumen emulsions were successfully used in South Africa and Australia [ TRB-EC102, 2006; Xiao, 2010] .During the application of bitumen emulsion, the water must be separated from the bitumen phase and evaporate.This separation is called breaking. After complete evaporation of the water, the bitumen particles will coalesce and bond together to develop mechanical properties. This strength development is curing.4. 1.2 nanoclay modified bitumen emulsionThe most preferred and widely used nanoclays are organically modified smectite clays with a 2: 1-type layey structure such as montmorillonite, saponite, etc [ Ammala , 2007] . All these layered silicates have the same crystalline structure and normally have a thickness of about 1 nanometer and a length of about 50 ~ 1 000 nanometers.In nanoclay modified bitumen emulsion, three possible particle dispersions can be distinguished as Fig. 1 shows [Xiao, 2010]. In the case of type one (see Fig. 1( a) ) , all the nanoclay particles are dispersed in the bitumen droplets. In this case, after breaking and curing the particles are dispersed in the binder between the aggregates. In the second type (see Fig. 1( b) ) , all of the nanoclay particles are dispersed in the water phase. After breaking and full curing, the particles are surrounding at the boundaries of the bitumen droplet s. The third type( see Fig. 1( c) ) is a combination of the first two types. Some of the particles are dispersed in the bitumen droplets while the others are dispersed in the water phase. In this condition, after breaking and curing the nanoclay particles both occur in the binder and between the bitumen droplets.These dispersion types have a significant influence on the properties of bitumen residues. Further investigations need to be carried on for checking these dispersions.Fig . 2 shows the possible outstanding properties of nanoclay modified bitumen emulsion on outside chemical resistance [Xiao, 2010] . With the unmodified bitumen emulsion after curing on the pavement surface, fuel, moisture and ultraviolet radiation can affect the binder directly. These can decrease the performance and cause raveling and ageing problems. When nanoclay modified bitumen emulsions are used for surface treatment, four steps can be dist inguished during breaking and curing. First, nanoclay modified bitumen emulsion consist s mainly of water, bitumen drop and nanoclay layers. Second, the water phase evaporates during the breaking and curing process. Then, bitumen droplets adhere to nanoclay particles, causing clusters to form the binder. At the last, binder is formed with nanoclay layers inside.The dispersed nanoclay particles can decrease surface damages due to fuel, moisture, air, etc. to a certain extent, resulting in better chemical and ageing resistance.4.2 Epoxy modified bitumensThe epoxy modified bitumen binder is a two phase chemical system in which the continuous phase is an acid cured epoxy and the discontinuous phase is a mixture of specialized bitumens, which makes the mixture performdifferent from a traditional asphalt mixture.4. 2. 1 Properties of epoxy modified bitumensEpoxy modified bitumen was used for pavement treatment long time ago and has achieved better properties than unmodified bitumen. In 1967, it was used to strengthen the surface of San Francisco Bay smile-long San Mateo-Hay ward Bridge. After more than 40 years, the bridge surface is reported to be in excellent condition.The special structure of epoxy modified bitumen makes it perform different from traditional bitumen. It does not become brittle at low temperature and does not melt at high temperature. Epoxy modified bitumen is a flexible material that can be applied in thin surface layers. When used on roads, it sets quickly enough to allow early traffic even before full curing, which enables the road to be reopened withintwo hours [ Xiao, 2010] .Epoxy modified bitumen is reported to be extremely durable as w ell as flexible. Surfaces with epoxy modified bitumen obtained better skid resistance and produce less noise than bitumen based sealers. Epoxy modified bitumen has extremely high temperature stability and strength, superior rutting resistance, excellent adhesion properties, high resistance to surface abrasion and is sufficiently fuel resistance [ Elliot t, 2008; Xiao, 2010] .4.2.2 Two-component epoxy modifiedbitumenTwo-component epoxy modified bitumen is acold mix application material. It is a two componentreactive material based on two components. One is amix of bitumen, bitumen-compatible epoxides andadditives. The other one is a mix of hardeners. After mixing of these two component s, there will be a fast react ion leading to epoxy resin within a bitumen based matrix.The tensile strength of Esha Seal 2C, which is a kind of two-component epoxy modified bitumen, obtained from ICOPAL BV, was evaluated using the Direct T ensile Test . Fig. 3 shows the tensile strengthafter different curing times and temperatures.Results indicate that the curing rate of epoxy modified bitumen emulsion depends on the curing temperature. The tensile strength increases with increasing curing time temperature . The tensile strength after full curing is higher than thetensile strength of bitumen, which implies that roads can be reopened for traffic very quickly w hen epoxy modified bitumens are applied in the surface layer.4. 3 Waterborne resinsWaterborne resins use water as the main volatile liquid component . It always shows good adhesion and the resistance to fuel, water and chemical is good. New technologies in waterborne systems provide unique technical solutions to get good properties, such as good adhesion to concrete and acidic resistance. With the waterborne two-component technology, coating manufacturers can formulate high-performance coatings without a cosolvent and achieve the same or better properties. Here waterborne polyurethane and epoxy resins will be discussed.4. 3. 1 Waterborne polyurethane resinsPolyurethane is a polymer consisting of a chain of organic units joined by urethane carbamate links. Polyurethane resins are formed from the reaction of an isocyanate with compounds containing active hydrogen, as Fig.4 shows. When the two components are mixed the hydroxyl groups ( - OH) in the resin react with the isocyanate groups ( N=C=O) in the hardener and a three dimensional molecular structure is produced[Weiss, 1997] .Because only one isocyanate group can react with one hydroxyl group, it is possible to vary the ratio of hydroxyl groups and isocyanate groups slightly either w ay in order to modify the mechanical properties of the system.Basically, waterbornepolyurethanes can be described asreactive or non-reactive polymerscontaining urethane and urea groupswhich are stabilized in water byinternal or external emulsifiers. Thesedifferent hydrophilic modify cationsallow the production of stablewaterborne polyurethanes with average particle sizes between 10 nm and 200 nm. Waterborne polyurethane resin is a water-based aliphatic polyurethane emulsion.Waterborne polyurethanes are environmental friendly. They provide a tough, durable and highly flexible binder. The advantages associated with polyurethane coatings are their high tensile strength, excellent adhesion properties and chemical/ mechanical resistance. Properties of waterborne polyurethanes can be improved by adding modifiers, such as organoclay layers [ Kim, 2003; Xiao, 2010] .Addagrip 1000 System resin is a two-component polyurethane resin designed by Addagrip Surface Treatments UK Ltd. It can be used for sealing to protect asphalt surfaces from erosion caused by frostdamage, chemical at tack and aviation fuel spillage. Areas treated over the last twenty years at military and civil air fields have prevented further deterioration and increased the service life of the concrete pavement by an estimated 10~ 15 years. Table 2 show s the properties of the samples before and after surface treatment with Addagrip 1000 System resin. 10 cm x 10 cmx10 cm blocks w ere used. The sample surfaces w ere heated and dried by a hot compressedair system before the resin w as sprayed onto the surface [Addagrip Ltd. ] . After surface reatment with this kind of polyurethane resin, the water and fuel resistance can be improved significantly.4. 3. 2 Waterborne epoxy resinsEpoxy is a copolymer. It is formed from two different chemicals, the resin and the hardener. Most common epoxy resins are produced from a reaction between Epichlorhydrin and bispheno-l A, see Fig.5[Weiss,1997] .Waterborne epoxy resin, with excellent adhesion properties, is another possible alternative. Waterborne epoxy resin is a stable resin material prepared by dispersing epoxy resin in the form of particles or droplet s into the dispersion medium based on water as a continuous phase.Application ofwaterborne epoxy resinsis not onlyconvenient but alsocauses no pollution tothe environmentand no harm to thehuman body. Afteradding a properamount of curing/ solidifying agent, advantages like high strength ,high-temperature resistance, chemical resistance, fatigue resistance, and high antiaging ability can be achieved [ Xiao, 2010; Weiss, 1997]5 ConclusionCTS are widely used for pavement surface treatments because of their excellent adhesion properties and good fuel resistance. How ever, because of their high PAHs content s, which are considered as human carcinogens, CTS are not allowed anymore in some of the developed counties. In order to eliminate the significant threat of pollution to our environment, w e should stop using CTS. Instead, modified bitumen emulsions, epoxy modified bitumen, waterborne polyurethanes and waterborne epoxy resins could achievecomparable or better properties than CTS. All of them have good adhesion, excellent chemical and ageing resistance. Epoxy modified bitumen has extremely high temperature stability and strength. Application of waterborne resins is convenient and the curing rate can be easily adjusted by changing the ratio of chemical components. And, the most important, these alternatives are environmental friendly.AcknowledgementsThe scholarship from the China Scholarship Council is acknowledged. T he authors would like to express thanks to ICOPAL BV for their materials and technical supports.References[1] AddagripLtd.www .adda grip [2] Ammala A, Hill A J.Poly( M-Xylene Adipamide)-Kaolinite and Poly( M-XyleneAdipamide)-Montmorillonite Nanocomposites [J] . Journal of Applied Polymer Science, 2007(104):1377- 1381.[3] Austin. http: / /www .ci. austin. tx . us/ watershed/ coaltar- ban. htm. Austin Bans Use of Coal Tar Sealants-first in Nation,2005.[4] CCTIR.China Coal Tar Industry Report 2006-2010.[R],2008.[5] Elliott R. 2008. Epoxy Asphalt: Concept and Properties. Workshop of TRB 2008.[6] IARC. Polynuclear Aromatic 4 Bitumens , Coal Tars and Der ived Products,Shale Oils and Soots. IARC Monographs on the Evaluation of Carcinogenic Risk of Chemicals to Humans,Vol. 35. Lyon, France:International Agency for Research on Cancer,1985.[7] Kennedy J. Alter native Materials and Techniques for Road Pavement Construction[R] . London: DOE Energy Efficiency Office,1997.[8] Kim B K, Seo J W, Jeong H M. Morphology and Properties of Waterborne Polyurethane/ clay Nanocomposite [J]. European[9] SCHER. Scientific Committee on Health and Environmental Risks. Coal tar pitch, high temperature Human Health Part. CAS No: 65996- 93- 2. EINECS No: 266- 028-2.[10] Thom N H. Asphalt Cracking: A Nottingham Perspective [J].Engenaria Civil/ Civil Engineering, 2006(26) : 75- 84.[11] TRB-EC102. Asphalt Emulsion Technology. Transportation Research Board[S], 2006.[12] Van Leest A J, Gaar keuken G. The F O D. Resistance of Sur face Layers on Airfields in the Netherlands; in Situ and Laboratory Testing [R] . 2005 European Airport Pavement Workshop, 2005. [13] Van Metre P C, Mahler B J. Trends in Hydrophobic Organic Contaminants in Urban and Reference Lake Sediments Across the United States, 1970- 2001[J]. Environmental Science and Technology,2005, 39( 15) : 5567- 5574.[14] Weiss K D. Paint and Coatings: A Mature Industry in Transition [J].Progress in Polymer Science, 1997, 22(2):203- 245.[15] Xiao Y. Literature Review on Possible Alternatives to Tar for Antiskid Layers . Delft University o f Technology, Road and Railway Engineering Section[R] . Report No.7-10-185-1,the Nether lands.。
本科毕业设计(论文)外文翻译译文
本科毕业设计（论文）外文翻译译文学生姓名：院（系）：油气资源学院专业班级：物探0502指导教师：完成日期：年月日地震驱动评价与发展：以玻利维亚冲积盆地的研究为例起止页码：1099——1108出版日期：NOVEMBER 2005THE LEADING EDGE出版单位：PanYAmericanYEnergyvBuenosYAiresvYArgentinaJPYBLANGYvYBPYExplorationvYHoustonvYUSAJ.C.YCORDOVAandYE.YMARTINEZvYChacoYS.A.vYSantaYCruzvYBolivia 通过整合多种地球物理地质技术，在玻利维亚冲积盆地，我们可以减少许多与白垩纪储集层勘探有关的地质技术风险。
通过对这些远景区进行成功钻探我们可以验证我们的解释。
这些方法包括盆地模拟，联井及地震叠前同时反演，岩石性质及地震属性解释，A VO/A V A,水平地震同相轴，光谱分解。
联合解释能够得到构造和沉积模式的微笑校正。
迄今为止，在新区有七口井已经进行了成功钻探。
基质和区域地质。
Tarija/Chaco盆地的subandean 褶皱和冲断带山麓的中部和南部，部分扩展到玻利维亚的Boomerange地区经历了集中的成功的开采。
许多深大的泥盆纪气田已经被发现，目前正在生产。
另外在山麓发现的规模较小较浅的天然气和凝析气田和大的油田进行价格竞争，如果他们能产出较快的油流而且成本低。
最近发现气田就是这种情况。
接下来，我们赋予Aguja的虚假名字就是为了讲述这些油田的成功例子。
图1 Aguja油田位于玻利维亚中部Chaco盆地的西北角。
基底构造图显示了Isarzama背斜的相对位置。
地层柱状图显示了主要的储集层和源岩。
该油田在Trija和冲积盆地附近的益背斜基底上，该背斜将油田和Ben i盆地分开（图1），圈闭类型是上盘背斜，它存在于连续冲断层上，Aguja有两个主要结构：Aguja中部和Aguja Norte,通过重要的转换压缩断层将较早开发的“Sur”油田分开Yantata Centro结构是一个三路闭合对低角度逆冲断层并伴随有小的摆幅。
毕业设计英文 翻译(原文)
编号：毕业设计(论文)外文翻译（原文）院（系）：桂林电子科技大学专业：电子信息工程学生姓名： xx学号： xxxxxxxxxxxxx 指导教师单位：桂林电子科技大学姓名： xxxx职称： xx2014年x月xx日Timing on and off power supplyusesThe switching power supply products are widely used in industrial automation and control, military equipment, scientific equipment, LED lighting, industrial equipment,communications equipment,electrical equipment,instrumentation, medical equipment, semiconductor cooling and heating, air purifiers, electronic refrigerator, LCD monitor, LED lighting, communications equipment, audio-visual products, security, computer chassis, digital products and equipment and other fields.IntroductionWith the rapid development of power electronics technology, power electronics equipment and people's work, the relationship of life become increasingly close, and electronic equipment without reliable power, into the 1980s, computer power and the full realization of the switching power supply, the first to complete the computer Power new generation to enter the switching power supply in the 1990s have entered into a variety of electronic, electrical devices, program-controlled switchboards, communications, electronic testing equipment power control equipment, power supply, etc. have been widely used in switching power supply, but also to promote the rapid development of the switching power supply technology .Switching power supply is the use of modern power electronics technology to control the ratio of the switching transistor to turn on and off to maintain a stable output voltage power supply, switching power supply is generally controlled by pulse width modulation (PWM) ICs and switching devices (MOSFET, BJT) composition. Switching power supply and linear power compared to both the cost and growth with the increase of output power, but the two different growth rates. A power point, linear power supply costs, but higher than the switching power supply. With the development of power electronics technology and innovation, making the switching power supply technology to continue to innovate, the turning points of this cost is increasingly move to the low output power side, the switching power supply provides a broad space for development.The direction of its development is the high-frequency switching power supply, high frequency switching power supply miniaturization, and switching power supply into a wider range of application areas, especially in high-tech fields, and promote the miniaturization of high-tech products, light of. In addition, the development and application of the switching power supply in terms of energy conservation, resource conservation and environmental protection are of great significance.classificationModern switching power supply, there are two: one is the DC switching power supply; the other is the AC switching power supply. Introduces only DC switching power supply and its function is poor power quality of the original eco-power (coarse) - such as mains power or battery power, converted to meet the equipment requirements of high-quality DC voltage (Varitronix) . The core of the DC switching power supply DC / DC converter. DC switching power supply classification is dependent on the classification of DC / DC converter. In other words, the classification of the classification of the DC switching power supply and DC/DC converter is the classification of essentially the same, the DC / DC converter is basically a classification of the DC switching power supply.DC /DC converter between the input and output electrical isolation can be divided into two categories: one is isolated called isolated DC/DC converter; the other is not isolated as non-isolated DC / DC converter.Isolated DC / DC converter can also be classified by the number of active power devices. The single tube of DC / DC converter Forward (Forward), Feedback (Feedback) two. The double-barreled double-barreled DC/ DC converter Forward (Double Transistor Forward Converter), twin-tube feedback (Double Transistor Feedback Converter), Push-Pull (Push the Pull Converter) and half-bridge (Half-Bridge Converter) four. Four DC / DC converter is the full-bridge DC / DC converter (Full-Bridge Converter).Non-isolated DC / DC converter, according to the number of active power devices can be divided into single-tube, double pipe, and four three categories. Single tube to a total of six of the DC / DC converter, step-down (Buck) DC / DC converter, step-up (Boost) DC / DC converters, DC / DC converter, boost buck (Buck Boost) device of Cuk the DC / DC converter, the Zeta DC / DC converter and SEPIC, the DC / DC converter. DC / DC converters, the Buck and Boost type DC / DC converter is the basic buck-boost of Cuk, Zeta, SEPIC, type DC / DC converter is derived from a single tube in this six. The twin-tube cascaded double-barreled boost (buck-boost) DC / DC converter DC / DC converter. Four DC / DC converter is used, the full-bridge DC / DC converter (Full-Bridge Converter).Isolated DC / DC converter input and output electrical isolation is usually transformer to achieve the function of the transformer has a transformer, so conducive to the expansion of the converter output range of applications, but also easy to achieve different voltage output , or a variety of the same voltage output.Power switch voltage and current rating, the converter's output power is usually proportional to the number of switch. The more the number of switch, the greater the output power of the DC / DC converter, four type than the two output power is twice as large,single-tube output power of only four 1/4.A combination of non-isolated converters and isolated converters can be a single converter does not have their own characteristics. Energy transmission points, one-way transmission and two-way transmission of two DC / DC converter. DC / DC converter with bi-directional transmission function, either side of the transmission power from the power of lateral load power from the load-lateral side of the transmission power.DC / DC converter can be divided into self-excited and separately controlled. With the positive feedback signal converter to switch to self-sustaining periodic switching converter, called self-excited converter, such as the the Luo Yeer (Royer,) converter is a typical push-pull self-oscillating converter. Controlled DC / DC converter switching device control signal is generated by specialized external control circuit.the switching power supply.People in the field of switching power supply technology side of the development of power electronic devices, while the development of the switching inverter technology, the two promote each other to promote the switching power supply annual growth rate of more than two digits toward the light, small, thin, low-noise, high reliability, the direction of development of anti-jamming. Switching power supply can be divided into AC / DC and DC / DC two categories, AC / AC DC / AC, such as inverters, DC / DC converter is now modular design technology and production processes at home and abroad have already matured and standardization, and has been recognized by the user, but AC / DC modular, its own characteristics make the modular process, encounter more complex technology and manufacturing process. Hereinafter to illustrate the structure and characteristics of the two types of switching power supply.Self-excited: no external signal source can be self-oscillation, completely self-excited to see it as feedback oscillation circuit of a transformer.Separate excitation: entirely dependent on external sustain oscillations, excited used widely in practical applications. According to the excitation signal structure classification; can be divided into pulse-width-modulated and pulse amplitude modulated two pulse width modulated control the width of the signal is frequency, pulse amplitude modulation control signal amplitude between the same effect are the oscillation frequency to maintain within a certain range to achieve the effect of voltage stability. The winding of the transformer can generally be divided into three types, one group is involved in the oscillation of the primary winding, a group of sustained oscillations in the feedback winding, there is a group of load winding. Such as Shanghai is used in household appliances art technological production of switching power supply, 220V AC bridge rectifier, changing to about 300V DC filter added tothe collector of the switch into the transformer for high frequency oscillation, the feedback winding feedback to the base to maintain the circuit oscillating load winding induction signal, the DC voltage by the rectifier, filter, regulator to provide power to the load. Load winding to provide power at the same time, take up the ability to voltage stability, the principle is the voltage output circuit connected to a voltage sampling device to monitor the output voltage changes, and timely feedback to the oscillator circuit to adjust the oscillation frequency, so as to achieve stable voltage purposes, in order to avoid the interference of the circuit, the feedback voltage back to the oscillator circuit with optocoupler isolation.technology developmentsThe high-frequency switching power supply is the direction of its development, high-frequency switching power supply miniaturization, and switching power supply into the broader field of application, especially in high-tech fields, and promote the development and advancement of the switching power supply, an annual more than two-digit growth rate toward the light, small, thin, low noise, high reliability, the direction of the anti-jamming. Switching power supply can be divided into AC / DC and DC / DC two categories, the DC / DC converter is now modular design technology and production processes at home and abroad have already matured and standardized, and has been recognized by the user, but modular AC / DC, because of its own characteristics makes the modular process, encounter more complex technology and manufacturing process. In addition, the development and application of the switching power supply in terms of energy conservation, resource conservation and environmental protection are of great significance.The switching power supply applications in power electronic devices as diodes, IGBT and MOSFET.SCR switching power supply input rectifier circuit and soft start circuit, a small amount of applications, the GTR drive difficult, low switching frequency, gradually replace the IGBT and MOSFET.Direction of development of the switching power supply is a high-frequency, high reliability, low power, low noise, jamming and modular. Small, thin, and the key technology is the high frequency switching power supply light, so foreign major switching power supply manufacturers have committed to synchronize the development of new intelligent components, in particular, is to improve the secondary rectifier loss, and the power of iron Oxygen materials to increase scientific and technological innovation in order to improve the magnetic properties of high frequency and large magnetic flux density (Bs), and capacitor miniaturization is a key technology. SMT technology allows the switching power supply has made considerable progress, the arrangement of the components in the circuit board on bothsides, to ensure that the light of the switching power supply, a small, thin. High-frequency switching power supply is bound to the traditional PWM switching technology innovation, realization of ZVS, ZCS soft-switching technology has become the mainstream technology of the switching power supply, and a substantial increase in the efficiency of the switching power supply. Indicators for high reliability, switching power supply manufacturers in the United States by reducing the operating current, reducing the junction temperature and other measures to reduce the stress of the device, greatly improve the reliability of products.Modularity is the overall trend of switching power supply, distributed power systems can be composed of modular power supply, can be designed to N +1 redundant power system, and the parallel capacity expansion. For this shortcoming of the switching power supply running noise, separate the pursuit of high frequency noise will also increase, while the use of part of the resonant converter circuit technology to achieve high frequency, in theory, but also reduce noise, but some The practical application of the resonant converter technology, there are still technical problems, it is still a lot of work in this field, so that the technology to be practical.Power electronics technology innovation, switching power supply industry has broad prospects for development. To accelerate the pace of development of the switching power supply industry in China, it must take the road of technological innovation, out of joint production and research development path with Chinese characteristics and contribute to the rapid development of China's national economy.Developments and trends of the switching power supply1955 U.S. Royer (Roger) invented the self-oscillating push-pull transistor single-transformer DC-DC converter is the beginning of the high-frequency conversion control circuit 1957 check race Jen, Sen, invented a self-oscillating push-pull dual transformers, 1964, U.S. scientists canceled frequency transformer in series the idea of switching power supply, the power supply to the size and weight of the decline in a fundamental way. 1969 increased due to the pressure of the high-power silicon transistor, diode reverse recovery time shortened and other components to improve, and finally made a 25-kHz switching power supply.At present, the switching power supply to the small, lightweight and high efficiency characteristics are widely used in a variety of computer-oriented terminal equipment, communications equipment, etc. Almost all electronic equipment is indispensable for a rapid development of today's electronic information industry power mode. Bipolar transistor made of 100kHz, 500kHz power MOS-FET made, though already the practical switching power supply is currently available on the market, but its frequency to be further improved. Toimprove the switching frequency, it is necessary to reduce the switching losses, and to reduce the switching losses, the need for high-speed switch components. However, the switching speed will be affected by the distribution of the charge stored in the inductance and capacitance, or diode circuit to produce a surge or noise. This will not only affect the surrounding electronic equipment, but also greatly reduce the reliability of the power supply itself. Which, in order to prevent the switching Kai - closed the voltage surge, RC or LC buffers can be used, and the current surge can be caused by the diode stored charge of amorphous and other core made of magnetic buffer . However, the high frequency more than 1MHz, the resonant circuit to make the switch on the voltage or current through the switch was a sine wave, which can reduce switching losses, but also to control the occurrence of surges. This switch is called the resonant switch. Of this switching power supply is active, you can, in theory, because in this way do not need to greatly improve the switching speed of the switching losses reduced to zero, and the noise is expected to become one of the high-frequency switching power supply The main ways. At present, many countries in the world are committed to several trillion Hz converter utility.the principle of IntroductionThe switching power supply of the process is quite easy to understand, linear power supplies, power transistors operating in the linear mode and linear power, the PWM switching power supply to the power transistor turns on and off state, in both states, on the power transistor V - security product is very small (conduction, low voltage, large current; shutdown, voltage, current) V oltammetric product / power device is power semiconductor devices on the loss.Compared with the linear power supply, the PWM switching power supply more efficient process is achieved by "chopping", that is cut into the amplitude of the input DC voltage equal to the input voltage amplitude of the pulse voltage. The pulse duty cycle is adjusted by the switching power supply controller. Once the input voltage is cut into the AC square wave, its amplitude through the transformer to raise or lower. Number of groups of output voltage can be increased by increasing the number of primary and secondary windings of the transformer. After the last AC waveform after the rectifier filter the DC output voltage.The main purpose of the controller is to maintain the stability of the output voltage, the course of their work is very similar to the linear form of the controller. That is the function blocks of the controller, the voltage reference and error amplifier can be designed the same as the linear regulator. Their difference lies in the error amplifier output (error voltage) in the drive before the power tube to go through a voltage / pulse-width conversion unit.Switching power supply There are two main ways of working: Forward transformand boost transformation. Although they are all part of the layout difference is small, but the course of their work vary greatly, have advantages in specific applications.the circuit schematicThe so-called switching power supply, as the name implies, is a door, a door power through a closed power to stop by, then what is the door, the switching power supply using SCR, some switch, these two component performance is similar, are relying on the base switch control pole (SCR), coupled with the pulse signal to complete the on and off, the pulse signal is half attentive to control the pole voltage increases, the switch or transistor conduction, the filter output voltage of 300V, 220V rectifier conduction, transmitted through the switching transformer secondary through the transformer to the voltage increase or decrease for each circuit work. Oscillation pulse of negative semi-attentive to the power regulator, base, or SCR control voltage lower than the original set voltage power regulator cut-off, 300V power is off, switch the transformer secondary no voltage, then each circuit The required operating voltage, depends on this secondary road rectifier filter capacitor discharge to maintain. Repeat the process until the next pulse cycle is a half weeks when the signal arrival. This switch transformer is called the high-frequency transformer, because the operating frequency is higher than the 50HZ low frequency. Then promote the pulse of the switch or SCR, which requires the oscillator circuit, we know, the transistor has a characteristic, is the base-emitter voltage is 0.65-0.7V is the zoom state, 0.7V These are the saturated hydraulic conductivity state-0.1V-0.3V in the oscillatory state, then the operating point after a good tune, to rely on the deep negative feedback to generate a negative pressure, so that the oscillating tube onset, the frequency of the oscillating tube capacitor charging and discharging of the length of time from the base to determine the oscillation frequency of the output pulse amplitude, and vice versa on the small, which determines the size of the output voltage of the power regulator. Transformer secondary output voltage regulator, usually switching transformer, single around a set of coils, the voltage at its upper end, as the reference voltage after the rectifier filter, then through the optocoupler, this benchmark voltage return to the base of the oscillating tube pole to adjust the level of the oscillation frequency, if the transformer secondary voltage is increased, the sampling coil output voltage increases, the positive feedback voltage obtained through the optocoupler is also increased, this voltage is applied oscillating tube base, so that oscillation frequency is reduced, played a stable secondary output voltage stability, too small do not have to go into detail, nor it is necessary to understand the fine, such a high-power voltage transformer by switching transmission, separated and after the class returned by sampling the voltage from the opto-coupler pass separated after class, so before the mains voltage, and after the classseparation, which is called cold plate, it is safe, transformers before power is independent, which is called switching power supply.the DC / DC conversionDC / DC converter is a fixed DC voltage transformation into a variable DC voltage, also known as the DC chopper. There are two ways of working chopper, one Ts constant pulse width modulation mode, change the ton (General), the second is the frequency modulation, the same ton to change the Ts, (easy to produce interference). Circuit by the following categories:Buck circuit - the step-down chopper, the average output voltage U0 is less than the input voltage Ui, the same polarity.Boost Circuit - step-up chopper, the average output voltage switching power supply schematic U0 is greater than the input voltage Ui, the same polarity.Buck-Boost circuit - buck or boost chopper, the output average voltage U0 is greater than or less than the input voltage Ui, the opposite polarity, the inductance transmission.Cuk circuit - a buck or boost chopper, the output average voltage U0 is greater than or less than the input voltage Ui, the opposite polarity, capacitance transmission.The above-mentioned non-isolated circuit, the isolation circuit forward circuits, feedback circuit, the half-bridge circuit, the full bridge circuit, push-pull circuit. Today's soft-switching technology makes a qualitative leap in the DC / DC the U.S. VICOR company design and manufacture a variety of ECI soft-switching DC / DC converter, the maximum output power 300W, 600W, 800W, etc., the corresponding power density (6.2 , 10,17) W/cm3 efficiency (80-90)%. A the Japanese Nemic Lambda latest using soft-switching technology, high frequency switching power supply module RM Series, its switching frequency (200 to 300) kHz, power density has reached 27W/cm3 with synchronous rectifier (MOSFETs instead of Schottky diodes ), so that the whole circuit efficiency by up to 90%.AC / DC conversionAC / DC conversion will transform AC to DC, the power flow can be bi-directional power flow by the power flow to load known as the "rectification", referred to as "active inverter power flow returned by the load power. AC / DC converter input 50/60Hz AC due must be rectified, filtered, so the volume is relatively large filter capacitor is essential, while experiencing safety standards (such as UL, CCEE, etc.) and EMC Directive restrictions (such as IEC, FCC, CSA) in the AC input side must be added to the EMC filter and use meets the safety standards of the components, thus limiting the miniaturization of the volume of AC / DC power, In addition, due to internal frequency, high voltage, current switching, making the problem difficult to solve EMC also high demands on the internal high-density mountingcircuit design, for the same reason, the high voltage, high current switch makes power supply loss increases, limiting the AC / DC converter modular process, and therefore must be used to power system optimal design method to make it work efficiency to reach a certain level of satisfaction.AC / DC conversion circuit wiring can be divided into half-wave circuit, full-wave circuit. Press the power phase can be divided into single-phase three-phase, multiphase. Can be divided into a quadrant, two quadrant, three quadrants, four-quadrant circuit work quadrant.he selection of the switching power supplySwitching power supply input on the anti-jamming performance, compared to its circuit structure characteristics (multi-level series), the input disturbances, such as surge voltage is difficult to pass on the stability of the output voltage of the technical indicators and linear power have greater advantages, the output voltage stability up to (0.5)%. Switching power supply module as an integrated power electronic devices should be selected。
毕业设计的英文翻译----开放式控制器体系结构 - 过去,现在和未来
Open Controller Architecture - Past, Present and FutureGunter Pritschow (Co-ordinator), Yusuf Altintas, Francesco Jovane, Yoram Koren, Mamoru Mitsuishi, Shozo Takata, Hendrik van Brussel, Manfred Weck, Kazuo YamazakiAbstractOpen Control Systems are the key enabler for the realization of modular and re-configurable manufacturing systems. The large number of special purpose machines and the high level of automation have led to an increasing importance of open control systems based on vendor neutral standards. This paper gives an overview on the past, present and future of Open Controller Architecture. After reflecting on the different criteria, categories and characteristics of open controllers in general, the CNC products in the market are evaluated and an overview on the world-wide research activities in Europe, North America and Japan is given. Subsequently the efforts to harmonize the different results are described in order to establish a common world-wide standard in the future. Due to the “mix-and-match’’ nature of open controllers concentrated attention must be paid to testing mechanisms in the form of conformance and interoperability tests.Keywords: Open architecture control, CNC, Machine tool1 INTRODUCTIONOpen Architecture Control (OAC) is a well known term in the field of machine control. Since the early nineties several initiatives world-wide have worked on concepts for enabling control vendors, machine tool builders and end-users to benefit more from flexible and agile production facilities. The main aim was the easy implementation and integration of customer-specific controls by means of open interfaces and configuration methods in a vendor-neutral, standardized environment [13][19].The availability and broad acceptance of such systems result in reduced costs and increased flexibility. Software can be reused and user-specific algorithms or applications can be integrated. Users can design their controls according to a given configuration. This trend was forced both by the increasing number of special purpose machines with a high level of automation and the increasing development costs for software (Figure 1).Figure 1: CNC Hardware and software -Actual trend existingIn the past the CNC market was dominated by heterogeneous, device-oriented systems with proprietary hardware and software components. The tight coupling of application software, system software and hardware led to very complex and inflexible systems. Great efforts were made to maintain and further develop the products according to new market requirements. Modern CNC approaches, which comprise extensive functionality to achieve a high quality and flexibility of machining results combined with a reduced processing time, favor PC- based solutions with a homogenous, standardized environment (Figure 2). The structure is software- oriented and configurable due to defined interfaces and software platforms. Open control interfaces are necessary for continuously integrating new advanced functionality into control systems and are important for creating re-configurable manufacturing units [17]. Unbundling hardware and software allows profiting from the short innovation cycles of the semiconductor industry and information technology. With the possibility for reusing software components, the performance of the overall system increases simply by upgrading the hardware platform.Figure 2: PC-based, software-oriented Control SystemsThere are a lot of benefits for suppliers and users of open control systems (Figure 3) [7]. CNC designers and academics benefit from a high degree of openness coveringalso the internal interfaces of the CNC. For CNC users the external openness is much more important. It provides the methods and utilities for integrating user-specific applications into existing controls and for adapting to user-specific requirements, e.g. adaptable user interfaces or collection of machine and production data. The external openness is mainly based on the internal openness but has functional or performance Iimitations .2 STATE OF THE ART2.1 Control Systems and their interfacesControls are highly sophisticated systems due to very strict requirements regarding real-time and reliability. For controlling the complexity of these systems hardware and software interfaces are an essential means. The interfaces of control systems can be divided into two groups-external and internal interfaces (Figure4).External InterfacesThese interfaces connect the control system to superior units, to subordinate units and to the user. They can be divided into programming interfaces and communication interfaces. NC and PLC programming interfaces are harmonized by national or international standards, such as RS-274, DIN 66025 or IEC 61131-3. Communication interfaces are also strongly influenced by standards. Fieldbus systems like SERCOS, Profibus or DeviceNet are used as the interface to drives and 110s. LAN (Local Area Network) networks mainly based on Ethernet and TCP/lP do reflect the interfaces to superior systems.Internal InterfacesInternal interfaces are used for interaction and data- exchange between components that build up the control- system core. An important criterion in this area is the support of real-time mechanisms. To achieve a re-configurable and adaptable control the internal architecture of the control system is based on a platform concept. The main aims are to hide the hardware-specific details from the software components and to establish a defined but flexible way of communication between the software components. An application programming interface(API) ensures these requirements. The whole functionality of a control system is subdivided into several encapsulated, modular software components interacting via the defined API.2.2 Hardware and software structure of control systemsFigure 5 shows different variants for the hardware structures of control systems. Variant a) shows an analog drives interface with position controller in the control system core. Each module of this structure uses its own processor which leads to a large variety of vendor-specific hardware. Combining modules leads to a significant reduction of the number of processors. Variant b) shows intelligent digital drives with integrated control functionality, which result from higher capacity, miniaturization and higher performance of the processors. Variant c) shows a PC-based single processor solution with a real-time extension of the operating system. All control-functions run as software tasks in the PC-based real-time environment.2.3 Market overviewThe controls available in the market provide different levels of openness according to the criteria shown in Figure 6. An important criterion is the use of a standardized computing platform (i.e. hardware, operating system and middleware) as an environment to execute the HMI and CNC software. Besides this, the connectivity of the CNC to upper and lower factory levels must be guaranteed. Application Programming Interfaces (API) are used to integrate third party software in the CNC products. Al though most of today’s controls offer openness concerning the operator-related control functions (Human-Machine Interface, HMI) only few controls allow users to modify their low-level control algorithms to influence the machine-related control functions.Figure 7 gives an overview of the characteristics of today’s control s ystems regarding the degree of openness.Although many control systems provide open interfaces for software integration (e.g. OPC) there is still no common definition of data which is passed back and forth via the programming interface. Therefore, the control systems available on the market today do not implicitly support “plug-and-play” features. To improve this situation, the fieldbus systems can serve as a role model (see Figure 8). The variety of different fieldbus systems has led to the broad consensus that harmonizing the application-oriented interfaces is desirable in order to hide the plurality and the complexity of the systems from the user. Most fieldbus organizations are already using so-called device profiles in order to support the interchangeability of the devices of different vendors.For example, the SERCOS interface standard (IEC61491) for the cyclic and deterministic communication between CNC and drives has defined the semantics forapprox. 400 parameters describing drive and control functions which are used by the devices of different vendors.3 DEFINITIONS AND CATEGORIES OF OPENNESS3.1 DefinitionsThe “Technical Committee of Open Systems” of IEEE defines an open system as follows: “An open system provides capabilities that enable properly implemented applications to run on a variety of platforms from multiple vendors, interoperate with other system applications and present a consistent style of interaction with the user” (IEEE 1003.0).To estimate the openness of a controller the following criteria can be applied (Figure 9):Portability. Application modules (AM) can be used on different platforms without any changes, while maintaining their capabilities.Extendibility. A varying number of AM can run on a platform without any conflicts.Inferoperability. AM work together in a consistent manner and can interchange data in a defined way.Scalability. Depending on the requirements of the user, functionality of the AM and performance and size of the hardware can be adapted.To fulfill the requirements of the IEEE-definition and these criteria of openness, an open control system must be:vendor neutral. This guarantees independence of single proprietary interests.consensus-driven. It is controlled by a group of vendors and users (usually in the form of a user group or an interested group).standards-based. This ensures a wide distribution in the form of standards (national/international standards or de-facto standards).freely available. It is free of charge to any interested party.3.2 Categories of Open Control SystemsIf we speak of openness in control systems, the following categories can be identified (Figure 10):Open HMl: The openness is restricted to the non-real-time part of the control system. Adaptations can be made in user oriented applications.Kernel with restricted openness: The control kernel has a fixed topology, but offers interfaces to insert user-specific filters even for real-time functions.Open Control System: The topology of the control kernel depends on the process. It offers interchangeability, scalability, portability and interoperability.Open control systems that are available today mostly offer the possibility for modifications in the non-real-time part in a fixed software topology. They lack the necessary flexibility and are not based on vendor-neutral standards.3.3 RequirementsA vendor-neutral open control system can only be realized if the control functionality is subdivided in functional units and if well-defined interfaces between these units are specified (Figure 11). Therefore modularity can be identified as the key for an open system architecture. In determining the module complexity there is an obvious trade-off between the degree of openness and the cost of integration [6]. Smaller modules provide a higher level of openness and more options, but increase the complexity and integration costs. Furthermore such a low level of granularity can lead to much higher demands for resources and it may even deteriorate the real-time performance of the overall system.Combining modules in the manner of “mix-and-match’’ requires a comprehensive set of standard Application Programming Interfaces (APIs). For vendor-neutral open control systems the interfaces need to be standardized and broadly accepted. Due to the complexity of such modular systems the definition of a system architecture is recommendable and helpful. This leads to the introduction of so-called system platforms (Figure 12). These platforms encapsulate the specifics of a computing system by absorbing the characteristics of hardware, operating system and communication. The availability of such middleware systems facilitates the easy porting of application software and also the interoperability of application modules even in distributed heterogeneous environments.Due to the possibility to “mix-and-match’’ modules via standardized interfaces the quality of the overall system is determined by the degree of the interoperability between the single modules (see Section 5).4 SYSTEMS ON THE WAY TO THE MARKET4.1 Major international activitiesOSEC (Japan)The OSE (Open System Environment for Manufacturing) consortium was established in December 1994. Three project phases were carried out until March 1999 [1][2][3]. The OSEC Architecture was intended to provide end users, machine makers, control vendors, software vendors, system integrators, etc. a standard platform for industrial machine controllers, with which they can add their own unique values to the industrial machines, and hence promote the technical and commercial development of the industrial machines. The OSEC API is defined in the form of an interface protocol, which is used to exchange messages among controller software components representing the functionality and the real- time cycle. Each functional block can be encapsulated as an object so it is not necessary to deal with how a functional block processes messages to it at architecture level (Figure 13). Although the structure of functional blocks can be defined uniquely by the OSEC architecture from a logical point of view, the system is neither determined nor limited at its implementation phase because there are so many options for implementations. These options may include system contrivances such as device driver, interprocess communication, installation mechanisms such as static library and DLL, hardware factors like selection of controller card, and implementations of software modules added for execution control and/or monitoring of various software. In other words, the implementation model to realize the architecture model is not limited to a particular model. In this way, it is assured to incorporate various ideas in the implementation model depending on the system size or its hardware implementation and/or utilization.JOP (Japan)In parallel to the OSE consortium activities, MSTC formed the Open-Controller Technical Committee (OC- TC) from 1996 to 2000, under the umbrella of JOP (Japanese Open Promotion Group). The objectives of OC-TC were to provide the opportunities for various companies to discuss and work together on the standardization of open controller technologies. The OC- TC was also expected to act as liaison between domestic and international activities in this field. OC-TC was participated by approximately 50 members, which included major Japanese controller vendors, machine tool builders, integrators, users, and academics. Some of the members represented the other groups concerning open controllers such as the OSE consortium and the FA Intranet Promotion Group .One of the working groups was engaged in developing a standard API for interfacing between NC and PC-based HMI. It should be also effective for the communication between NC and an upper level management controller. The work was carried out based on the proposals from the major controller vendors and that from the OSE consortium. The developed specifications were named PAPI and released July, 1999 [4] [5]. PAPI was approved as a JIS (Japan Industrial Standard) technical report and published in October, 2000. To demonstrate the effectiveness of the specifications developed by OC-TC, in Nagoya in October 1999, two CNCs manufactured by different vendors were connected to a Windows NT machine in which the same HMI systems developed by the University of Tokyo were implemented (Figure 14). Since any specific controller architecture is not assumed, PAPI can be implemented in various types of existing CNC systems, such as PC + proprietary NC, PC + NC board, and Software NC on PC+110 board. The HMI system communicates with the CNCs via PAPI which is a function-oriented software library in the programming language C. The PAPI interface is neutralizing the vendor-specific interface by mapping the PAPI calls to the vendor-specific API and protocol.OMAC (USA)The Open Modular Architecture Controllers (OMAC) Users Group is an industry forum to advance the state of controller technology [l0]. An effort was undertaken within OMAC to define API specification for eventual submittal to an established standards body. The OMAC API adopted a component-based approach to achieve plug-and-play modularization, using interface classes to specify the API [11]. For distributed communication, component-based technology uses proxy agents to handle method invocations that cross process boundaries. OMAC API contains diffe rent “sizes” and “types” of reusab le plug-and-play components - component, module, and task - each with a unique Finite State Machine (FSM) model so that component collaboration is performed in a known manner. The term component applies to reusable pieces of software that serves as a building block within an application while the term module refers to a container of components. Tasks are components used to encapsulate programmable functional behavior consisting of a series of steps that run to completion, including support for starting, stopping, restarting, halting, and resuming, and may be run multiple times while a controller is running. Tasks can be used to build controller programs consisting of a series of Transient Tasks, with ability to restart and navigate, or as standalone Resident Tasks to handle specialized controller requirements, (e.g., axis homing or ESTOP).To integrate components, a framework is necessary to formalize the collaborations and other life cycle aspects in which components operate. The OMAC API uses Microsoft Component Object Model (COM) as the initial framework in which to develop components, with the expected benefit that control vendors could then concentrate on application-specific improvements that define their strategic market-share - as opposed to spending valuable programming resources reinventing and maintaining software “plumbing.”The primary problem with COM framework, specifically under the Windows 2000 operating system, is the lack of hard, real-time preemptive scheduling, but third party extensions to Windows 2000 can be used to overcome this requirement.Figure 15 illustrates a sketch of OMAC API controller functionality. The HMI module is responsible for human interaction with a controller including presenting data, handing commands, and monitoring events and in the OMAC API “mirrors” the actual controller with references to all the major modules and components via proxy agents. The Task Coordinator module is responsible for sequencing operations and coordinating the various modules in the system based on programmable Tasks. The Task Coordinator can be considered the highest level Finite State Machine in the controller. A Task Generator module translates an application-specific control program (e.g., RS 274 part program) into a series of application-neutral Transient Tasks. The Axis Group module is responsible for coordinating the motions of individual axes, transforming an incoming motion segment specification into a sequence of equi-time- spaced setpoints for the coordinated axes. The Axis module is responsible for servo control of axis motion, transforming incoming motion setpoints into setpoints for the corresponding actuators 10 points. The Control Law component is responsible for servo control loop calculations to reach specified setpoints. OSACA (Europe)In Europe the ESPRIT project OSACA (Open System Architecture for Controls within Automation Systems) was initiated in 1992 with the aim to unite European interests and to create a vendor-neutral standard for open control systems[9][16].It was supported by major European control vendor and machine tool builders. OSACA reached a mature state already in April 1996 having at its disposal a stable set of specifications and a tested pool for system software. Based on these results, several application-oriented projects were carried out. In 1988 two pilot demonstrators in the automotive industry proved the interoperability of OSACA-compliant controllers and applications. The OSACA association eth currently 35 members from all over the word is the lasting organization to keep and maintain the OSACA-related specifications.The basic technical approach of the OSACA architecture is the hierarchical decomposition of control functionality into so-called functional units (Figure 16).For each of these functional units (e.g. motion control, motion control manager, axescontrol, logic control, etc.) the interfaces are specified by applying object-oriented information models. This technique is similar to the approach of MAP/MMS but with a limited and manageable number of object classes.The data interface consists of several variable objects that support the read and/or write access to data structure(data flow).The data can be of a simple type or of a complex type(array, structure, union).By using formal templates(Figure17) all the characteristics of a single interface object are specified. These elements cover the name (e.g, “mc-active-feed-override”), the type (e.g. UNS32: 32-bit unsigned value), the scaling (e.g. 0.l%),the range and the access rights (read only, to all the major modules and components via proxy write only, read/write) of the data. An additional description is to avoid misinterpretations of the use of the data. The process interface consists of several process objects that are used to describe the dynamic behavior (control flow) of the application modules by means of finite state machine (FSM). The state machines are described by static states, dynamic states and transitions to change the states of a given state-machine. The transitions can handle input and output parameters to pass data between application modules via the communication platform. The formal template for such process interfaces consists of an unambiguous description and the following attributes: list of static states (identifier, list of possible transitions), list of dynamic states (identifier) and a list of transitions (input parameters, output parameters, return codes). The process interface can also be used to activate application-specific functions in form of procedure calls. The interoperability of distributed application modules is supported by an infrastructure (so-called OSACA platform) which comprises client-server principles, synchronous and asynchronous calls and event handling via any underlying communication protocol and media (e.g. by using the TCP/lP protocol). A dedicated configuration runtime system is handling the system’s startup and shutdown. Besides, it also allows an easy reconfiguration of the system.开放式控制器体系结构- 过去，现在和未来摘要开放式控制系统是用于模块化和可重新配置制造系统实现的关键推动者。
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关于[CoCl(PR3)3]†二氯甲烷和膦烷基化的c-cl双键活化作用的计算研究
密度函数理论计算已经应用在[CoCl(PR3)3]二氯甲烷中c-cl键的激活对[CoCl3(CH2PR3)(PR3)2]。
将二氯甲烷溶液计算（PCM方法）在一个[CoCl(PMe3)3]模型系统显示c-cl键裂解步骤包含不同的机制。
第一个c-cl键裂解的步骤发生在三重表面上并且阻碍cl原子吸收kcal mol−1的能量。
活化分子的再结合将给反式-[CoCl2(CH2Cl)(PMe3)3]单体一个+1.8 kcal mol−1总自由能的变化。
不寻常的c-cl活化过程是由于二氯甲烷中心的Co亲核攻击伴随着Cl−键的消失。
第二个c-cl键发生亲核攻击是通过PMe3中CH2Cl配体形成一个新的P-C键并去掉一个Cl−.这个工程可能发生在一个分子（PME3解离后）或者分子内。
这些过程都大约需要消耗12 kcal mol−1能量。
[CoCl3(CH2PMe3)(PMe3)2]关于[CoCl(PMe3)3]的生成常数，[CoCl2(PMe3)2] and 2 PMe3是一个强放热过程与类似的实验过程中所得到的的结果相同。
引言
二氯甲烷中c-cl键的活化基于两个相对不活泼的C(sp3)–Cl键的基本理论观点。
许多情况下二氯甲烷中c-cl键的断裂发生在一个富电子的金属中心给LNM–CH2Cl配合物。
随后的第二个c-cl键的断裂是不常见的，虽然有足够多的反应物能够满足反应结果：(i)第二富电子中心可形成μ-CH2配合物(ii)通过Cl−的中间位移由一个基本的CO-配体或加入的亲核试剂形成LnM–CH2Cl，E, 给出了LnMCH2E的类型(E = e.g. PR3,5 OR−,5c NR2H,6 py;7是导致c-c键形成的一种情况下在报告8中已经说明)；(iii)双c-cl键的激活可能发生在一个单一的金属中心形成一个亚烷基络合物，LnMvCH2.在大多数情况下富电子的第二或第三排电子会影响到这些转换。
尽管如此，二氯甲烷中c-cl键的活化同时作为一个在有机合成中的亚甲基转移途径。
实际上这个方法已经应用在二氯甲烷末端炔烃和胺在金属催化剂作用下合成炔。
最近，Braunstein and co-workers报告了一个罕见的例子二氯甲烷中c-cl键在第一行过渡金属配合物的活化，特别是[CoCl(PR3)3] (PR3 = PPh3, Pn-Bu3, PMePh2, PMe2Ph)。
整体的反应涉及一个{CH2}单元中二氯甲烷进入一个Co–PR3键形成一个Co–CH2PR3的过程（表一）。
这个反应机制表现出的特征有(i)初始二氯甲烷给予Co(III)–CH2Cl类物质的氧化性；(ii)在CH2Cl和一个PR3配体的结合形成一个Co(III)–CH2PR3中间产物；(iii)最后的产物随着[CoCl(PR3)3]第二分子生成常数生成[CoCl2(CH2PR3)-(PR3)]和[CoCl2(PR3)2]。
我们对本文提出的反应机理的密度函数理论建模很感兴趣。
相比较C(sp2)-卤化物，对C(sp3)的分子激活过程的计算研究相对较少（相对于单个原子或离子而言）。
现有的研究结果表明R3C(sp3)-X可以通过亲核反应通过一个富电子置换活化一个X−。
这会产生一个[LnM(CR3)]+中间产物和一个自由的X−能够形成[LnM(CR3)(X)]的氧化产物。
在这两个步骤大程度的电荷分离过程中突出了模型环境对反应的影响，为了得到良好的实验结果溶剂解离作用相当重要。
除了这样的两电子过程，单电子的逐步激进过程也是另一种可能发生的过程并且和第一行的过渡金属元素有密切的联系。
实际上最近Budzelaar and coll关于DFT计算的结果表明c-cl键激活一个[Co(Ph)(diiminepyridine)]结合物是通过最初的卤族元素抽象理解的相当复杂的一个过程。
在本篇文章中，我们将评估二氯甲烷的第一个c-cl键在[CoCl(PR3)3]中机械理论的可能性并且与CH2Cl/PR3结合生成Co(III)类中间产物的结果。
表-1
计算细节
用Gaussian 09, Revision A.0216进行计算得到BP86的计算结果。
SDD相对ECP理论和相关基础用于Co, P 和Cl,在P (ζ = 0.387) and Cl (ζ = 0.640)上添加d轨道的偏差函数。
6-31G**用于建立所有基础的其他原子。
测试的关键在于还进行了一个不同的函数范围和这些相似趋势的过渡态的计算和实验。
我们采用[CoCl(PMe3)3]作为一个简单情况下的模型；尽管大多数关于[CoCl(PPh3)3]的实验数据是可用的，也在关于c-cl键激活化学反应在Pn-Bu3, PMePh2,PMe2Ph相似物中有相关的的报告。
在本文研究的几个反应步骤中cl离子从金属中心移动和因此带来的显著电荷分离的探讨。
由于这个原因，优化过渡态结构（例如cl-的亲核取代在第一个c-cl键断裂的过程）或在气相中给出不切实际的结果。
因此在说明二氯甲烷所有优化作用的影响包括通过极化连续介质模型（PCM）程序。
UAHF的半径被用于在PCM中心的计算当中。
固定点被确定为最小值或通过分析频率计算
过度态，过渡态的特点是可以通过IRC计算确定之后的状态。
在(1TS(2+-4)
和TS(4mer,cis-6Cax,trans))两种情况下我们无法找到真正在转变过程中所利用的状态；在这种情况下热量衡算对应一个线性的高点转移过程。
能量的数据被用来优化解决自由能的问题。
为了便于比较生成物作为离子对计算的解离过程（以cl-的解离来说）或较弱作用的产物（当PMe3或一个CH2Cl原子团失去），这些结构被定义为通过IRC /参与过渡态的优化。
所有的关键结构在高速自旋和低速自旋下进行了优化。
最小的能量交叉点（MECPs）之间的旋转表面被Harvey和他的同事用于开发应用程序。