光纤通信外文资料及翻译
附件1：外文资料翻译译文
光纤通信在配电网自动化上的应用
1前言
广泛分布的电话主导着通讯网络的第一个阶段并贯通了90多年。但是，电报领先于电话３0多年,打字机领先于电话半个世纪。1844年,电报的发明者,塞缪尔-莫尔斯从华盛顿发送第一条电报给他在马里兰-巴尔的摩的同事—韦尔。1876年，贝尔发明电话，之后不久,人们就意识到有线电话必须集中到一个中心点上，电话到电话的链接才能建立起来。这些点是手动开关板，有值班操作员控制。之后引进了机电开关,在１88９年，第一个双端可动的步进交换机产生。
第二次世界大战之后,整个长途网络自动化后，自动电话进入了黄金期。晶体管的发明推动了电子在交换系统中的运用，带来了2０实际50年代后期第一代电子交换机的发展。电子交换机使设计和建成的交换机拥有更大的容量。
通讯网络的第二个阶段发生在20世纪6０年代，包含三个主要的里程碑:软件,数字交换,和卫星的发射部署。
通信网络的第三个阶段发生在上世纪70年代，以数据网络和分组交换技术的引进为特征。为了实现电脑与分组交换网络的兼容性,１976年，国际电报电话咨询委员会建立了一个世界标准的协议，称为Ｘ.25。这个阶段的通讯网络以局域网的引进和推广为特征。１959年，光纤的产生在光通信领域带来了跨越式的技术发展。康宁光纤实验室发布第一个低能耗光纤，可以实现20Dｂ／km 损耗。
通讯网络的第四个阶段开始在上世纪8０年代,以综合业务数字网和移动通信的运用为特征。
随着国家经济的发展和人民生活水平的提高,人们对电力的需求日益增长，同时对供电的可靠性和供电质量提出了更高的要求。配网馈线自动化是配网系统提高供电可靠性最直接有效的技术手段之一。在近几年国家加大了对城网和农网的改造，国内各大供电局对配电网自动化的投入也在加大。在配网自动化实现的过程中，
我们发现通信问题是一个难点问题。在此，仅就光纤通信在配网自动化方面的应用谈一点认识和体会。
2配电网自动化对通信的要求
同调度SＣAＤA系统一样,配电自动化系统也需要一个有效的通信网,同时他有自己的特点：终端数量极多。配网系统拥有众多的开闭所、配电变压器、柱上断路器，要对这些设备进行监控就需要许多FTU和TTＵ，同时这些FTU随配电设备安装,地域分布广,通讯节点分散。
配网自动化系统的规模、复杂程度和自动化程度决定了通信系统应满足下述要求: (1)可靠性:
配网系统的通信设备有很多暴露在室外,环境恶劣，因此必须能够抵御高温、低温、日晒、雨淋、风雪、冰雹和雷电等自然环境的侵袭。同时,尽量避免各种电磁干扰，保证长期稳定可靠地工作，并要求在线路停电时，通信系统仍能正常工作。（2)经济性:
考虑到配电网系统的总体经济效益，通信系统的投资不应过大，力争充分利用现有的主网通信资源，进行主、配网整体规划,避免重复投资。
(３）寻址量大：
通信系统不仅要考虑目前及未来的数据传输的需要,还要考虑系统升级的要求。
(4)双向通信:
配网自动化要实现遥测、遥信、遥控功能，就必须要求具有双向通信能力。(5）容易操作和免维护。
根据以上的要求，伴随着光纤价格的下降，目前,光纤通信正广泛地应用于电力系统。
3光纤通信
自激光器和低损耗光纤问世以来,光纤通信系统以其技术、经济上无可比拟的优越性而迅速崛起,并风靡全球。该系统是以光纤为传输介质，以光为载波信号传递信息的通信系统,应用的光波波长为１.0～1．μm靘,整个系统由电端机、光端机、光缆和中继器构成。光纤可分为单模光纤(SMF）、多模光纤(MMF）、长波长低射散
光纤(LMF）、保偏光纤(PMＦ)及塑料光纤（POF）等很多种;常用的为单模和多模光纤,多模光纤就是传输多个光波模式，而单模光纤只传输一个光波模式。单模光纤比多模光纤传输距离长，目前一般地,光信号在多模光纤内可传6ｋm左右，在单模光纤内可传30ｋm。因此，单模光设备的价格要高于多模光设备。实用的光纤通常都是由多根光纤、加强芯、保护材料、固定材料等组合成光缆构成的传输线。
光纤MODEＭ可完成光信号与数字信号之间的相互转换。光纤ＭOＤEＭ一般有一个以上的数据口用以传递同步或异步信号。通信速率可达到2Ｍbpｓ或更高,
配网常用的通信速率一般为同步N×64K或异步１９2００bps以下。故足以满足配网通信的需要。
另外，还有一种光纤MODＥM具有双环自愈功能。这一功能使通信的可靠性大大增强。使通信不受影响，同时向主站发出相应的告警及定位信号,使维修人员及时修复故障段光缆。
4光纤通信的特点
光纤通信具有通信容量大，衰减小,不怕雷击，抗电磁干扰、抗腐蚀、保密性好、可靠性高、敷设方便等优点,不过投资费用相对较高，尤其对于城区内直埋式电缆线路的光纤敷设,施工费用将更大。
５光纤通信在配电网上的实现方案
光纤通信的组网方式非常灵活，可以构架成星型、链型、树状、网状、单纤网、双纤网、环上多分支、多环相交、多环相切等各种拓扑结构的网络。
根据配电自动化系统的特点,光纤网通常需组成环型网,并与计算机局域网连接，实现数据共享。
实际工程设计中,充分考虑到电力通信专网拓扑结构的复杂性,SDH传输系统可以采用多达１26个Ｅ1(2M口)全交叉连接和双主光环＋多光分支的设计思想。基本构架为1~3个SDH/ＳTＭ－1双纤自愈环相交或相切,而且在需要时,可通过更换光卡的方式在线升级为SDH／ＳTM-4。如果局调度中心局域网位于网络地理中心,建
议设计为相切环,以调度中心为切点;如果局调度中心局域网偏离网络地理中心,建议设计为相交环，由于调度中心不在交点，为了环间可靠转接，各环相交至少两点，互为保护路由。
6结束语
在实际的配网自动化的通信系统，必须构建一个成本低、收效高的双向通信系统，用可以接受的费用在可靠性和信息流量方面提供非常高的性能。同时，由于配电网自动化系统所要完成的功能太多而系统复杂,采用单一的通信系统来满足所有的功能需要是不现实的,也是不经济的。因此,在配电网自动化系统中,要应用多种通信方式,按综合的经济技术指标而选取其中最优的组合。在电力系统中较常用的通信方式还有一点多址数字微波、数传电台、无线扩频、专线电缆、邮电本地网、载波、扩频载波等，可供组网时选择。
Optical fiber commｕnｉcaｔion in ｐoweｒｄistribution autｏmatｉon applic ａtiｏns on ｐaｐer
1 Foreｗord
Tｈe fiｒsｔｐhase in the evｏｌｕｔｉon of ｃomｍｕnication networｋs ｉs ｄominａtｅd by thｅwidｅspread of tｅleｐhony anｄｃoveｒs ovｅr ９0 years ．Howｅvｅr ,the telegrapｈｐrｅceded tｈe tｅｌephｏnｅby mｏre th ａn３0 yeａｒs and the teletｙpewｒｉter by ｈalf a cｅntury ．In18４4, Saｍｕｅl Mｏｒse , ｔhe ｔeleｇｒapｈ’s inventor ,seｎt tｈe fｉrst teleｇrａp ｈmessage frｏm Waｓｈｉngton Ｄ.Ｃ. ｔo ｈｉs ｃoｌｅague Afｒｅd Ｖaｉl ｉn Bａltimore, Marylanｄ. Shｏrｔｌy ａｆｔｅr thｅiｎventionｏf ｔhe tel ｅｐhone bｙＡｌexaｎdeｒGrahan Bell in 1８76,it wａs rｅalizeｄtｈａt telephone wirｅs haｄto convｅrgｅon centraｌｐoiｎtｓｗｈｅre ｔｅｌep ｈｏnｅ-ｔｏ－teleｐhonｅconｎｅctioｎs could bｅmａde .Ｔhese ｐoinｔs wer ｅmanual swｉtcｈ-bｏaｒｄ，
Staｆfed bｙopeｒatｏｒ.Tｈiｓwas ｆolｌｏwｅd ｂy the intｒoducｔiｏn of eleｃtroｍechaniｃal ｓwitchｉng ａnd in １889,Almoｎd B．Stｒｏｗｇｅrｉnｖｅntedｔhe firｓt tｗo－motion sｔep－ｂ-stｅp swiｔcｈ.
Tｈe goｌden aｇｅof automatic telephｏｎy ｏccurred afteｒＷord War∏wｈen ｔhe eｎtｉre lｏng-distance netｗoｒk wａs ａutomatｅd .
Thｅ inveｎｔion oｆ tｈe transisｔoｒ spurred the applicatｉon oｆ
Ｅｌectｒoｎicｓto switchiｎｇsｙsｔｅms aｎｄｌeｄtoｔｈe deplｏyｍe ｎｔof thｅｆirｓt ｅｌectrｏniｃswiｔchiｎｇin thｅｌaｔe 1９５0s. Ｅlｅctrｏniｃswｉtchｉng mａde ｉt pｏssibleｔo ｄesigｎanｄｂuｉｌd swi ｔｃhes wｉｔhｇreaｔerｃaｐａｃity.
The ｓｅｃond pｈase ofｎetworkiｎg,ｗhich occｕｒred in the 19６
0s ,includｅd three major milｅstonｅs：sｏfｔｗａｒe switｃｈinｇ,ｄigital transm ｉssｉｏn ,and satellitｅdｅｐloｙmeｎt.
Tｈe ｔhird phase oｆtｈe evoｌｕｔion oｆcｏmｍunicatiｏn ｎetworks o ｃｃurrｅd ｉn the 19７0s and ｉs chａｒacterizeｄbｙtｈe intｒoｄｕｃtｉon ｏf data networks and pａｃkｅｒsｗitchiｎｇtechnoｌogy. To aｃｈieｖe ｃompaｔiｂilｉｔy beｔｗeen ｃomputerｓanｄｐacket－sｗｉtchｅｄｎｅtworｋ,the intｅrnatioｎal Tｅlｅgrａph and Ｔelephone CｏｎsuｌｔatiｖｅＣommｉｔtee(CCITＴfrom ｔｈe Frencｈacｒｏnym ｅstablished aｗｏrd-standard proｔocoｌ, ｃaｌled X．25 in １９7６. Thisｐｈase oｆneｔｗorｋｉng iｓalｓo chaｒaｃｔerｉzｅd ｂｙｔｈe intｒoduction andｗidｅacｃep ｔａnｃe of ｌocaｌareａｎｅtwoｒkｓ（LANs).The iｎvｅntｉon ｏf thｅla ｓer (whｉｃh standｓfoｒliｇht amplｉfｉcatiｏn bｙsimulaｔｅd emisｓion of rａdiaｔioｎ)in19５9 ｌeｄtｏmaｊor ｔechnicaｌｄｅｖeｌｏpment ｓinｔhe fiｅld ｏf opticaｌcommuniｃatiｏｎ.１970,Ｃoｒｎｉｎg Glａss Woｒks reported ｏｎｔｈｅfirst low－lｏss optical fiｂer （dopeｄsｉliｃa claｄfiber ) ｔｈat acｈiｅved ２０dB/km lｏｓs.
The fourｔh phａｓe of comｍunicaｔｉon ｎetworｋing,which begａn ｉｎ1980,is cｈaracｔeｒiｚeｄbｙthｅavaiｌaｂiｌｉｔy of tｈe ｉntegrate ｄｓervｉces digｉtal neｔwoｒｋs（ISＤN) and ｍobile cｏｍmｕniｃａtions.
Wｉｔh the developmｅnｔof nａtiｏnaｌeconomy aｎd peｏplｅ's li ｖing stanｄards improvｅ,peｏｐle＇s growing demand for elｅctｒicity，wｈilｅtｈe reｌｉaｂility aｎd ｐoｗeｒqualiｔy oｆｐoweｒsｕｐｐly pu ｔforwａrｄhigheｒｒequｉrements. Feeｄｅr Automaｔion is thｅrelｉａbiliｔｙof power supply distribｕｔion netwｏrk systｅms ｔo impｒoｖe ｔhe mｏst dirｅｃt and effectivｅmeaｎs of tｅｃhnolｏｇｙ. Cｏｕnｔries ｈas ｉncrｅasｅd iｎreｃent yearｓｏn tｈe cｉｔｙｎeｔwｏrｋan ｄtｈe trａnsformａtioｎｏfｒｕｒal pｏｗer nｅtworｋ, pｏwｅr supｐly ｂuｒeａusｏfｔhe ｍaｊｏｒdomｅstic iｎvestment iｎｄiｓｔriｂution aｕｔomａｔiｏｎisａlsoｉnｃｒｅａsing.Ａchievｅd in the distｒｉ
bution netｗｏｒk ａuｔoｍａｔioｎproｃｅss, ｗe fｏund thatｃommunication prｏblｅms iｓａdifficuｌt problem．In this,juｓt from the fibｅr－optiｃcoｍｍunｉcａtion ｎetｗｏｒｋｓin autoｍation aｐｐlicａtｉoｎs with lｉttle knoｗlｅdge ａbｏut and exｐｅｒience.
2 ＤisｔｒibutiｏｎAuｔｏｍaｔion reqｕiremｅnts for ｃommｕnicatｉｏn
SCＡＤＡsystem ｗiｔh the saｍe ｄｉsｐatcｈ, distribution automa ｔｉon sｙsｔeｍalso neｅdｓaｎeffectｉｖe cｏmmｕnｉｃation ｎetwork, and ｈｅhaｓhis ｏwｎｃharａcterｉstｉcs: the number of termiｎalｓveｒｙｍｕch. Sｙstｅm hａｓa large ｄistributｉon neｔｗｏｒk bｙopeni ｎg and cloｓinｇ,power distrｉｂutioｎtransforｍerｓ,cｉｒcuit brｅａｋｅrs columｎto monitor these deviｃｅs ｒｅquireｓ a nｕmber ｏf ＦTＵand TTU,while the FTU with tｈe ｐｏwｅｒdistrｉｂution equipment instａｌｌation, wiｄe gｅographical distribｕｔiｏn，cｏmmunication nodes scaｔterｅd.
Distribｕtioｎauｔｏmａtiｏn ｓｙsteｍｓize, complｅxity and ａuｔｏmatiｏｎｌeveｌoｆtｈe ｄeciｓiｏn oｆtｈe communication syｓtem shｏulｄmｅet the ｆollowiｎg ｒｅquｉｒemｅｎts:
(1）Ｒｅliabiｌiｔｙ:
Cｏmmunicatioｎｓequiｐmeｎt distributｉoｎneｔwｏrk syｓteｍs have many exposed ｏutdoors, bad eｎviｒonｍenｔ, ｓo mｕｓt bｅable to witｈstanｄheat，ｃold, sｕn，ｒaiｎ, ｓnow, ｈaiｌand ｌｉgｈtning ａｎd other ｎatural ａttackｓ. Meａnwｈile,try to avoid alｌｋｉnds of ｅｌｅｃｔroｍagneｔicｉntｅrfｅｒenｃe, ｔo eｎsurｅlｏｎg-term ｓtablｅand r ｅlｉaｂｌｅｗork,and asｋeｄｗｈen ｔhe ｌｉｎe poｗer faiｌuｒe, communicａtｉon systｅm can stiｌl wｏrk properly．
(2) ecｏnomy:
Takingｉnto ａccoｕｎt ｔｈｅoverａll economicｐｏwer diｓtriｂutiｏn sysｔem, ｃommｕnicaｔionｓｙstem, investment ｓhould ｎot be tｏo la ｒgｅ, and sｔrive tｏｍaｋe full usｅoｆｔｈe existing main neｔwｏrk comｍunicaｔiｏn reｓｏurceｓ, foｒthe Loｒd，tｈe ｏveｒall dｉsｔribution ｎｅtwork pｌａｎniｎｇ，avoｉｄdupｌiｃatiｏn of invｅｓtment.
(３)addｒeｓsｉng ｌaｒge：
Cｏmmuniｃation syｓtem not onｌy tｏconsideｒtｈe preｓent anｄｆuturｅdata ｎeｅds, bｕt also coｎｓidｅr tｈe upgrａｄe requiｒements.
（４) ｔwo-ｗay cｏmmunｉｃatiｏn:
Ｄisｔributionｎetworkａｕtｏmatｉon to ａchieve thｅteｌemｅtｒy, remote, reｍotｅcontroｌ, ｙoｕｍusｔｒequeｓt a twｏ-ｗay comｍunｉcat ｉon cａpabilitiｅｓ．
(5)easy ｏpeｒatiｏn and mainteｎancｅ.
Ａccordinｇｔｏthe abovｅrequirements,aloｎg with fｉbeｒprices dowｎ，ａt preseｎｔ，ｏptｉcａｌｆiber ｃommｕｎｉcation ｓystemｓa ｒe wｉdｅｌｙｕsed in eｌecｔric power.
3 OpticaｌFibｅr Cｏｍmｕｎicatｉoｎ
Sincｅｔｈe inｃeption of lasｅｒand low ｌｏss ｏpｔical ｆｉｂｅr,ｏｐticａｌfibeｒcommｕniｃａｔion syｓtem wｉtｈits technｉcaｌanｄ
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英文论文及中文翻译
International Journal of Minerals, Metallurgy and Materials Volume 17, Number 4, August 2010, Page 500 DOI: 10.1007/s12613-010-0348-y Corresponding author: Zhuan Li E-mail: li_zhuan@https://www.360docs.net/doc/759758165.html, ? University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg 2010 Preparation and properties of C/C-SiC brake composites fabricated by warm compacted-in situ reaction Zhuan Li, Peng Xiao, and Xiang Xiong State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China (Received: 12 August 2009; revised: 28 August 2009; accepted: 2 September 2009) Abstract: Carbon fibre reinforced carbon and silicon carbide dual matrix composites (C/C-SiC) were fabricated by the warm compacted-in situ reaction. The microstructure, mechanical properties, tribological properties, and wear mechanism of C/C-SiC composites at different brake speeds were investigated. The results indicate that the composites are composed of 58wt% C, 37wt% SiC, and 5wt% Si. The density and open porosity are 2.0 g·cm–3 and 10%, respectively. The C/C-SiC brake composites exhibit good mechanical properties. The flexural strength can reach up to 160 MPa, and the impact strength can reach 2.5 kJ·m–2. The C/C-SiC brake composites show excellent tribological performances. The friction coefficient is between 0.57 and 0.67 at the brake speeds from 8 to 24 m·s?1. The brake is stable, and the wear rate is less than 2.02×10?6 cm3·J?1. These results show that the C/C-SiC brake composites are the promising candidates for advanced brake and clutch systems. Keywords: C/C-SiC; ceramic matrix composites; tribological properties; microstructure [This work was financially supported by the National High-Tech Research and Development Program of China (No.2006AA03Z560) and the Graduate Degree Thesis Innovation Foundation of Central South University (No.2008yb019).] 温压-原位反应法制备C / C-SiC刹车复合材料的工艺和性能 李专，肖鹏，熊翔 粉末冶金国家重点实验室，中南大学，湖南长沙410083，中国（收稿日期：2009年8月12日修订：2009年8月28日;接受日期：2009年9月2日） 摘要：采用温压?原位反应法制备炭纤维增强炭和碳化硅双基体(C/C-SiC)复合材
计算机专业毕业设计说明书外文翻译(中英对照)
Talking about security loopholes Richard S. Kraus reference to the core network security business objective is to protect the sustainability of the system and data security, This two of the main threats come from the worm outbreaks, hacking attacks, denial of service attacks, Trojan horse. Worms, hacker attacks problems and loopholes closely linked to, if there is major security loopholes have emerged, the entire Internet will be faced with a major challenge. While traditional Trojan and little security loopholes, but recently many Trojan are clever use of the IE loophole let you browse the website at unknowingly were on the move. Security loopholes in the definition of a lot, I have here is a popular saying: can be used to stem the "thought" can not do, and are safety-related deficiencies. This shortcoming can be a matter of design, code realization of the problem. Different perspective of security loo phole s In the classification of a specific procedure is safe from the many loopholes in classification. 1. Classification from the user groups: ● Public loopholes in the software category. If the loopholes in Windows, IE loophole, and so on. ● specialized software loophole. If Oracle loopholes, Apach e,
外文翻译
Load and Ultimate Moment of Prestressed Concrete Action Under Overload-Cracking Load It has been shown that a variation in the external load acting on a prestressed beam results in a change in the location of the pressure line for beams in the elastic range.This is a fundamental principle of prestressed construction.In a normal prestressed beam,this shift in the location of the pressure line continues at a relatively uniform rate,as the external load is increased,to the point where cracks develop in the tension fiber.After the cracking load has been exceeded,the rate of movement in the pressure line decreases as additional load is applied,and a significant increase in the stress in the prestressing tendon and the resultant concrete force begins to take place.This change in the action of the internal moment continues until all movement of the pressure line ceases.The moment caused by loads that are applied thereafter is offset entirely by a corresponding and proportional change in the internal forces,just as in reinforced-concrete construction.This fact,that the load in the elastic range and the plastic range is carried by actions that are fundamentally different,is very significant and renders strength computations essential for all designs in order to ensure that adequate safety factors exist.This is true even though the stresses in the elastic range may conform to a recognized elastic design criterion. It should be noted that the load deflection curve is close to a straight line up to the cracking load and that the curve becomes progressively more curved as the load is increased above the cracking load.The curvature of the load-deflection curve for loads over the cracking load is due to the change in the basic internal resisting moment action that counteracts the applied loads,as described above,as well as to plastic strains that begin to take place in the steel and the concrete when stressed to high levels. In some structures it may be essential that the flexural members remain crack free even under significant overloads.This may be due to the structures’being exposed to exceptionally corrosive atmospheres during their useful life.In designing prestressed members to be used in special structures of this type,it may be necessary to compute the load that causes cracking of the tensile flange,in order to ensure that adequate safety against cracking is provided by the design.The computation of the moment that will cause cracking is also necessary to ensure compliance with some design criteria. Many tests have demonstrated that the load-deflection curves of prestressed beams are approximately linear up to and slightly in excess of the load that causes the first cracks in the tensile flange.(The linearity is a function of the rate at which the load is applied.)For this reason,normal elastic-design relationships can be used in computing the cracking load by simply determining the load that results in a net tensile stress in the tensile flange(prestress minus the effects of the applied loads)that is equal to the tensile strength of the concrete.It is customary to assume that the flexural tensile strength of the concrete is equal to the modulus of rupture of the
计算机专业外文文献及翻译
微软Visual Studio 1微软Visual Studio Visual Studio 是微软公司推出的开发环境，Visual Studio可以用来创建Windows平台下的Windows应用程序和网络应用程序，也可以用来创建网络服务、智能设备应用程序和Office 插件。Visual Studio是一个来自微软的集成开发环境IDE，它可以用来开发由微软视窗，视窗手机，Windows CE、.NET框架、.NET精简框架和微软的Silverlight支持的控制台和图形用户界面的应用程序以及Windows窗体应用程序，网站，Web应用程序和网络服务中的本地代码连同托管代码。 Visual Studio包含一个由智能感知和代码重构支持的代码编辑器。集成的调试工作既作为一个源代码级调试器又可以作为一台机器级调试器。其他内置工具包括一个窗体设计的GUI应用程序，网页设计师，类设计师，数据库架构设计师。它有几乎各个层面的插件增强功能，包括增加对支持源代码控制系统（如Subversion和Visual SourceSafe）并添加新的工具集设计和可视化编辑器，如特定于域的语言或用于其他方面的软件开发生命周期的工具（例如Team Foundation Server的客户端：团队资源管理器）。 Visual Studio支持不同的编程语言的服务方式的语言，它允许代码编辑器和调试器（在不同程度上）支持几乎所有的编程语言，提供了一个语言特定服务的存在。内置的语言中包括C/C + +中（通过Visual C++）,https://www.360docs.net/doc/759758165.html,（通过Visual https://www.360docs.net/doc/759758165.html,），C＃中（通过Visual C＃）和F＃（作为Visual Studio 2010），为支持其他语言，如M,Python,和Ruby等，可通过安装单独的语言服务。它也支持的 XML/XSLT,HTML/XHTML ,JavaScript和CSS.为特定用户提供服务的Visual Studio也是存在的：微软Visual Basic，Visual J＃、Visual C＃和Visual C++。 微软提供了“直通车”的Visual Studio 2010组件的Visual Basic和Visual C＃和Visual C + +，和Visual Web Developer版本，不需任何费用。Visual Studio 2010、2008年和2005专业版，以及Visual Studio 2005的特定语言版本（Visual Basic、C++、C＃、J＃），通过微软的下载DreamSpark计划，对学生免费。 2架构 Visual Studio不支持任何编程语言，解决方案或工具本质。相反，它允许插入各种功能。特定的功能是作为一个VS压缩包的代码。安装时，这个功能可以从服务器得到。IDE提供三项服务：SVsSolution，它提供了能够列举的项目和解决方案; SVsUIShell，它提供了窗口和用户界面功能（包括标签，工具栏和工具窗口）和SVsShell，它处理VS压缩包的注册。此外，IDE还可以负责协调和服务之间实现通信。所有的编辑器，设计器，项目类型和其他工具都是VS压缩包存在。Visual Studio 使用COM访问VSPackage。在Visual Studio SDK中还包括了管理软件包框架(MPF)，这是一套管理的允许在写的CLI兼容的语言的任何围绕COM的接口。然而，MPF并不提供所有的Visual Studio COM 功能。
1外文文献翻译原文及译文汇总
华北电力大学科技学院 毕业设计（论文）附件 外文文献翻译 学号：121912020115姓名：彭钰钊 所在系别：动力工程系专业班级：测控技术与仪器12K1指导教师：李冰 原文标题：Infrared Remote Control System Abstract 2016 年 4 月 19 日
红外遥控系统 摘要 红外数据通信技术是目前在世界范围内被广泛使用的一种无线连接技术，被众多的硬件和软件平台所支持。红外收发器产品具有成本低，小型化，传输速率快，点对点安全传输，不受电磁干扰等特点，可以实现信息在不同产品之间快速、方便、安全地交换与传送，在短距离无线传输方面拥有十分明显的优势。红外遥控收发系统的设计在具有很高的实用价值，目前红外收发器产品在可携式产品中的应用潜力很大。全世界约有1亿5千万台设备采用红外技术，在电子产品和工业设备、医疗设备等领域广泛使用。绝大多数笔记本电脑和手机都配置红外收发器接口。随着红外数据传输技术更加成熟、成本下降，红外收发器在短距离通讯领域必将得到更广泛的应用。 本系统的设计目的是用红外线作为传输媒质来传输用户的操作信息并由接收电路解调出原始信号，主要用到编码芯片和解码芯片对信号进行调制与解调，其中编码芯片用的是台湾生产的PT2262，解码芯片是PT2272。主要工作原理是：利用编码键盘可以为PT2262提供的输入信息，PT2262对输入的信息进行编码并加载到38KHZ的载波上并调制红外发射二极管并辐射到空间，然后再由接收系统接收到发射的信号并解调出原始信息，由PT2272对原信号进行解码以驱动相应的电路完成用户的操作要求。 关键字：红外线；编码；解码；LM386；红外收发器。 1 绪论
英文文献及中文翻译
毕业设计说明书 英文文献及中文翻译 学院：专 2011年6月 电子与计算机科学技术软件工程
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计算机专业外文文献翻译6
外文文献翻译（译成中文2000字左右）： As research laboratories become more automated,new problems are arising for laboratory managers.Rarely does a laboratory purchase all of its automation from a single equipment vendor. As a result,managers are forced to spend money training their users on numerous different software packages while purchasing support contracts for each. This suggests a problem of scalability. In the ideal world,managers could use the same software package to control systems of any size; from single instruments such as pipettors or readers to large robotic systems with up to hundreds of instruments. If such a software package existed, managers would only have to train users on one platform and would be able to source software support from a single vendor. If automation software is written to be scalable, it must also be flexible. Having a platform that can control systems of any size is far less valuable if the end user cannot control every device type they need to use. Similarly, if the software cannot connect to the customer’s Laboratory Information Management System (LIMS) database,it is of limited usefulness. The ideal automation software platform must therefore have an open architecture to provide such connectivity. Two strong reasons to automate a laboratory are increased throughput and improved robustness. It does not make sense to purchase high-speed automation if the controlling software does not maximize throughput of the system. The ideal automation software, therefore, would make use of redundant devices in the system to increase throughput. For example, let us assume that a plate-reading step is the slowest task in a given method. It would make that if the system operator connected another identical reader into the system, the controller software should be able to use both readers, cutting the total throughput time of the reading step in half. While resource pooling provides a clear throughput advantage, it can also be used to make the system more robust. For example, if one of the two readers were to experience some sort of error, the controlling software should be smart enough to route all samples to the working reader without taking the entire system offline. Now that one embodiment of an ideal automation control platform has been described let us see how the use of C++ helps achieving this ideal possible. DISCUSSION C++: An Object-Oriented Language Developed in 1983 by BjarneStroustrup of Bell Labs,C++ helped propel the concept of object-oriented programming into the mainstream.The term ‘‘object-oriented programming language’’ is a familiar phrase that has been in use for decades. But what does it mean? And why is it relevant for automation software? Essentially, a language that is object-oriented provides three important programming mechanisms:
毕业设计外文翻译资料
外文出处： 《Exploiting Software How to Break Code》By Greg Hoglund, Gary McGraw Publisher : Addison Wesley Pub Date : February 17, 2004 ISBN : 0-201-78695-8 译文标题： JDBC接口技术 译文： JDBC是一种可用于执行SQL语句的JavaAPI（ApplicationProgrammingInterface应用程序设计接口）。它由一些Java语言编写的类和界面组成。JDBC为数据库应用开发人员、数据库前台工具开发人员提供了一种标准的应用程序设计接口，使开发人员可以用纯Java语言编写完整的数据库应用程序。 一、ODBC到JDBC的发展历程 说到JDBC，很容易让人联想到另一个十分熟悉的字眼“ODBC”。它们之间有没有联系呢？如果有，那么它们之间又是怎样的关系呢？ ODBC是OpenDatabaseConnectivity的英文简写。它是一种用来在相关或不相关的数据库管理系统（DBMS）中存取数据的，用C语言实现的，标准应用程序数据接口。通过ODBCAPI，应用程序可以存取保存在多种不同数据库管理系统（DBMS）中的数据，而不论每个DBMS使用了何种数据存储格式和编程接口。 1．ODBC的结构模型 ODBC的结构包括四个主要部分：应用程序接口、驱动器管理器、数据库驱动器和数据源。应用程序接口：屏蔽不同的ODBC数据库驱动器之间函数调用的差别，为用户提供统一的SQL编程接口。 驱动器管理器：为应用程序装载数据库驱动器。 数据库驱动器：实现ODBC的函数调用，提供对特定数据源的SQL请求。如果需要，数据库驱动器将修改应用程序的请求，使得请求符合相关的DBMS所支持的文法。 数据源：由用户想要存取的数据以及与它相关的操作系统、DBMS和用于访问DBMS的网络平台组成。 虽然ODBC驱动器管理器的主要目的是加载数据库驱动器，以便ODBC函数调用，但是数据库驱动器本身也执行ODBC函数调用，并与数据库相互配合。因此当应用系统发出调用与数据源进行连接时，数据库驱动器能管理通信协议。当建立起与数据源的连接时，数据库驱动器便能处理应用系统向DBMS发出的请求，对分析或发自数据源的设计进行必要的翻译，并将结果返回给应用系统。 2．JDBC的诞生 自从Java语言于1995年5月正式公布以来，Java风靡全球。出现大量的用java语言编写的程序，其中也包括数据库应用程序。由于没有一个Java语言的API，编程人员不得不在Java程序中加入C语言的ODBC函数调用。这就使很多Java的优秀特性无法充分发挥，比如平台无关性、面向对象特性等。随着越来越多的编程人员对Java语言的日益喜爱，越来越多的公司在Java程序开发上投入的精力日益增加，对java语言接口的访问数据库的API 的要求越来越强烈。也由于ODBC的有其不足之处，比如它并不容易使用，没有面向对象的特性等等，SUN公司决定开发一Java语言为接口的数据库应用程序开发接口。在JDK1．x 版本中，JDBC只是一个可选部件，到了JDK1．1公布时，SQL类包（也就是JDBCAPI）
计算机外文资料翻译---Visual Basic简介
毕业设计(论文)外文资料翻译 系（院）：计算机科学系 专业：计算机科学与技术 姓名： 学号： 111001203 外文出处：Learn Visual Basic in 24 hours --Hour 1 Visual Basic at Work 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 Visual Basic简介 什么是Visual Basic Microsoft Visual Basic 5.0是旧的BASIC语言最近的最好的化身，在一个包里给你一个完全的Windows应用开发系统。Visual Basic (我们常称它VB)能让你写、编辑，并且测试Windows应用程序。另外，VB有包括你能用来写并且编译帮助文件那的工具，ActiveX控制，并且甚至因特网应用程序 Visual Basic是它本身的一个Windows应用程序。你装载并且执行VB系统就好象你做其它Windows程序。你将使用这个运行的VB程序创造另外的程序。虽然VB是一个非常地有用的工具，但VB只是一个程序员(写程序的人)用来写，测试，并且运行Windows应用程序的工具。 尽管程序员们经常可替交地使用术语程序和应用程序，当你正在描述一个Windows 程序时术语应用程序似乎最适合，因为一个Windows程序由若干份代表性的文件组成。这些文件以工程形式一起工作。通过双击一个图标或由以Windows开始应用程序运行启动菜单用户从Windows加载并且运行工程产生最终的程序。 过去的45年与计算机硬件一起的编程工具的角色已经演变。今天一种程序语言，例如Visual Basic，一些年以前与程序语言的非常不一致。Windows操作系统的视觉的天性要求比一些年以前是可利用的更先进的工具。在windowed环境以前，一种程序语言是你用来写程序的一个简单的基于文章工具。今天你需要的不只是一种语言，你需要一种能在windows系统内部工作并且能利用所有的绘画、多媒体、联机和Windows提供的多处理活动开发应用软件的绘图开发工具。Visual Basic是如此的一种工具。超过一种语言，Visual Basic让你产生与今天的Windows操作系统的每个方面互相影响的应用程序。如果在过去你已经注意Visual Basic，你将很惊讶今天的Visual Basic系统。现在VB 创造独立的运行时刻的一个真实的编辑器.EXE文件比先前的VB程序更快速执行。VB也包括若干个提供逐步的对话框问题的奇才，这些对话框问题通过应用程序指导你。VB的开发平台，一个叫开发者工作室的发展环境，现在支持和先进的Visual C++，Visual J++ 编辑器一样的特征。因此，一旦你学习微软的视觉的编程产品的之一，你将能熟练的使用其它编程语言在学习其它编程语言时你前面没有很长的弯路。 语言 今天编程语言不再和它们以前一样。语言自己没变得不太重要，而是应用软件的绘画接口已经变得更重要。 一台计算机不能理解任何人的说的语言。一种口语，例如意大利或英语，简单地太全面并且不明确，计算机不能理解。因此，我们必须适应机器并且学习计算机能理解的一种语言。VB的程序语言是相当简单的并且在最多的部分使用普通的英语词和短语。然而，语言明确。当你用Visual Basic语言写声明时，在一样的上下文以内声明从来没有多样的意思。
毕业设计外文资料翻译译文
附件1：外文资料翻译译文 包装对食品发展的影响 一个消费者对某个产品的第一印象来说包装是至关重要的，包括沟通的可取性，可接受性，健康饮食形象等。食品能够提供广泛的产品和包装组合，传达自己加工的形象感知给消费者，例如新鲜包装/准备，冷藏，冷冻，超高温无菌，消毒（灭菌），烘干产品。 食物的最重要的质量属性之一，是它的味道，其影响人类的感官知觉，即味觉和嗅觉。味道可以很大程度作退化的处理和/或扩展存储。其他质量属性，也可能受到影响，包括颜色，质地和营养成分。食品质量不仅取决于原材料，添加剂，加工和包装的方法，而且其预期的货架寿命（保质期）过程中遇到的分布和储存条件的质量。越来越多的竞争当中，食品生产商，零售商和供应商；和质量审核供应商有显着提高食品质量以及急剧增加包装食品的选择。这些改进也得益于严格的冷藏链中的温度控制和越来越挑剔的消费者。 保质期的一个定义是：在食品加工和包装组合下，在食品的容器和条件，在销售点分布在特定系统的时间能保持令人满意的食味品质。保质期，可以用来作为一个新鲜的概念，促进营销的工具。延期或保质期长的产品，还提供产品的使用时间，方便以及减少浪费食物的风险，消费者和/或零售商。包装产品的质量和保质期的主题是在第3章中详细讨论。 包装为消费者提供有关产品的重要信息，在许多情况下，使用的包装和/或产品，包括事实信息如重量，体积，配料，制造商的细节，营养价值，烹饪和开放的指示，除了法律准则的最小尺寸的文字和数字，有定义的各类产品。消费者寻求更详细的产品信息，同时，许多标签已经成为多语种。标签的可读性是为视障人士的问题，这很可能成为一个对越来越多的老年人口越来越重要的问题。 食物的选择和包装创新的一个主要驱动力是为了方便消费者的需求。这里有许多方便的现代包装所提供的属性，这些措施包括易于接入和开放，处置和处理，产品的知名度，再密封性能，微波加热性，延长保质期等。在英国和其他发达经济体显示出生率下降和快速增长的一个相对富裕的老人人口趋势，伴随着更加苛
中文和英文简历和专业英语材料翻译
韶关学院 期末考核报告 科目：专业英语 学生姓名： 学号： 同组人： 院系： 专业班级： 考核时间：2012年10月9日—2012年11月1 日评阅教师： 评分：
第1章英文阅读材料翻译 (1) 第2章中文摘要翻译英文 (3) 第3章中文简历和英文简历 (4) 第4章课程学习体会和建议 (6) 参考文献 (7)
第1章英文阅读材料翻译 Mechanization and Automation Processes of mechanization have been developing and becoming more complex ever since the beginning of the Industrial Revolution at the end of the 18th century. The current developments of automatic processes are, however, different from the old ones. The “automation” of the 20th century is distinct from the mechanization of the 18th and 19th centuries inasmuch as mechanization was applied to individual operations, wherea s “automation” is concerned with the operation and control of a complete producing unit. And in many, though not all, instances the element of control is so great that whereas mechanization displaces muscle, “automation”displaces brain as well. The distinction between the mechanization of the past and what is happening now is, however, not a sharp one. At one extreme we have the electronic computer with its quite remarkable capacity for discrimination and control, while at the other end of the scale are “ transfer machines” , as they are now called, which may be as simple as a conveyor belt to another. An automatic mechanism is one which has a capacity for self-regulation; that is, it can regulate or control the system or process without the need for constant human attention or adjustment. Now people often talk about “feedback” as begin an essential factor of the new industrial techniques, upon which is base an automatic self-regulating system and by virtue of which any deviation in the system from desired condition can be detected, measured, reported and corrected. when “feedback” is applied to the process by which a large digital computer runs at the immense speed through a long series of sums, constantly rejecting the answers until it finds one to fit a complex set of facts which have been put to it, it is perhaps different in degree from what we have previously been accustomed to machines. But “feedback”, as such, is a familiar mechanical conception. The old-fashioned steam engine was fitted with a centrifugal governor, two balls on levers spinning round and round an upright shaft. If the steam pressure rose and the engine started to go too fast, the increased speed of the spinning governor caused it to rise up the vertical rod and shut down a valve. This cut off some of the steam and thus the engine brought itself back to its proper speed. The mechanization, which was introduced with the Industrial Revolution, because it was limited to individual processes, required the employment of human labor to control each machine as well as to load and unload materials and transfer them from one place to another. Only in a few instances were processes automatically linked together and was production organized as a continuous flow. In general, however, although modern industry has been highly mechanized ever since the 1920s, the mechanized parts have not as a rule been linked together. Electric-light bulbs, bottles and the components of innumerable mass-produced