西安邮电大学专业英语重点译文.doc

一名词解释PCM pulse-code modulation脉冲编码调制PPM Pulse Position Modulation脉冲位置调制ASK amplitude shift keying幅移键控FSK frequencyshiftkeying频移键控BFSK binaryfrequencyshiftkeying二进制频移键控MSK minimumshiftkeying最小频移键控PSK phaseshiftkeying(PSK)相移键控FDM Frequencydivisionmultiplexing频分复用OFDMorthogonalfrequencydivisionmultiplexing正交频分复用TDMtimedivisionmultiplexing时分复用 WDMwavedivisionmultiplexing波分复用DWDMdensewavedivisionmultiplexing密集型波分复用PMamplitude/frequency/phasemodulation(AM/FM/PM)幅度/频/调制CPMcontinuousphasemodulation连续相位调制FDMAfrequencydivisionmultipleaccess(FDMA).频分多址TDMAtimedivisionmultipleaccess时分多址CDMA code division multiple access码分多址SDMAspacedivisionmultipleaccess空分多址GSMglobalsystemformobilecommunicatons全球数字移动通信系统MSmobilestation移动台 BTSbasetransceviver基站收发台BSCbasestationcontroller基站控制器 BSSbasestationsubsystem基站子系统MSCmobileswitchingcenter移动交换中心 AUCAuthenticationcenter鉴权中心VLRvisitorlocationregister访问位置寄存器EIR equipment identity register设备识别寄存器HLR home location register本地位置寄存器PSTN public switched telephone network公共电话交换网ISDNintegratedsercicesdigitalnetwork综合业务数字网ADSLasymmetricdigitalsubscriberline非对称数字用户线路NSSnetworkandswitchingsubsystem网络交换中心PBX private branch exchange程控交换机ATMasynchronoustransfermode异步传输模式 LANlocalareanetwork局域网IEEE Institute of Electrical and Electronics Engineers美国电气和电子工程师协会CSMA/CD Carrier Sense Multiple Access/Collision Detect载波监听多路访问/冲突检测MACmedium access control介质访问控制层LLClogical link control链路逻辑控制TCPTransmission Control Protocol传输控制协议FTP file transferprotocol文件传输协议JPEG JointPhotographicExpertsGroup联合图像专家小组MPEG Moving Pictures ExpertsGroup动态图像专家组NAPsnetworkaccesspoints网络接入点IXPsInternetexchangepoints互联网接入点SNAsystemsnetworkarchitecture系统网络体系结构OSI open system interconnection开放式系统互联GPS global positioning system全球定位系统ICMP：InternetControlMessageProtocol控制报文协议IGMP：InternetGroupManagementProtocol组管理协议FDDfrequency division duplex频分双工 TDDtimedivisionduplex时分双工PLLphaselockloop锁相环ADCanalog-to-digitalconverter模数转换器SSMAspreadspectrummultipleaccess扩频多址系统VLC variable length coding可变长编码HDTVhigh-definitiontevevision高清晰度电视VODvideo-on-demand视频点播技术OSSoperationsupportsystems运营支撑系统DRMdigitalrightsmanagement数字版权管理CISC/SISCcomplex/simpleinstruction set computer复杂/精简指令集计算机PLMNpubliclandmobilenetwork公共陆地移动网MULmobileuserlink移动用户链路 GWLgatewaylink网关链路ISLintersatellitelinks内部卫星链路BRI basicrateinterface基本速率接口PRI primaryrateinterface基群速率接口 TAterminaladapter终端适配器APDavalanchephotodiode雪崩光电二极管PINpositive-intrinsicnegative本征光电二极管TE transverseelectricmode模电模式 TM tranaversemagnetic横磁模式LP linearlypolarizedmode线性模式 STBsettopbox机顶盒二翻译SoWhatisCloudComputing?WeseeCloudComputingasacomputingmodel,notatechnology.Inthismodel“customers”plugintothe“cloud”toaccessITresourceswhicharepricedandprovided“on-demand”.Essentially,ITresourcesarerentedandsharedamongmultipletenantsmuchasofficespace,apartments,orstoragespacesareusedbytenants.DeliveredoveranInternetconnection,the“cloud”replacesthecompanydatacenterorserverprovidingthesameservice.Thus,CloudComputingissimplyITservicessoldanddeliveredovertheInternet.RefertosectionofTypesofCloud Computing.译文：我们把云计算看作是一种计算模型,而不是一种技术.在这个模型中,客户插入到云中访问IT资源,而这些资源被定价且按需提供。从本质上讲，IT资源和写字楼，公寓，或是存储空间一样是被多个用户租用和共享的。通过互联网连接，“云”取代该公司的数据中心或服务器提供相同的服务。因此，云计算是简单的在互联网上出售及交付的IT服务。参考部分云计算的类型。2.PaaS(Platform as a Service)Deliversvirtualizedserversonwhichcustomerscanrunexistingapplicationsordevelopnewoneswithouthavingtoworryaboutmaintainingtheoperatingsystems,serverhardware,loadbalancingorcomputingcapacity.ThesevendorsprovideAPIsordevelopmentplatformstocreateandrunapplicationsinthecloude.g.usingtheInternet.ManagedServiceproviderswithapplicationservicesprovidedtoITdepartmentstomonitorsystemsanddownstreamapplicationssuchasvirusscanningfore-mailarefrequentlyincludedinthiscategory译文：提供虚拟化服务器上，客户可以运行现有应用程序或者开发新的应用程序，无需担心维护操作系统，服务器硬件，负载均衡或计算能力。这些供应商提供应用接口或开发平台来创建和运行在云中的应用程序以互联网为例。管理服务提供商与应用服务提供给IT部门监视系统和下游应用，如电子邮件病毒扫描经常被包括在这一类里。3.AlthoughanalystsdefinetheIoTintermsofconnectedeverydayobjects,thenatureoftheconnectionremainstobedetermined.Atwo-wayconnectionbymeansoftheInternetProtocolconstitutestheidealcase,buttheoriginatorsoftheIoTconceptappeartohaveemphasizedasimplermodelofRFIDqueryandresponse.TheIoTwillbeinextricablefromsensornetworksthatmonitorthingsbutdonotcontrolthings.Bothconnectedeverydayobjectsandsensornetworksbothleverageacommonsetoftechnologicaladvancestowardminiature,power-efficientsensing,processing,andwirelesscommunication.AnalystscommonlydescribetwodistinctmodesofcommunicationintheInternetofThings:thingtopersonandthing-to-thingcommunication.译文：虽然分析师用连接日常物品来定义物联网，但物联网连接的性质仍有待确定。通过互联网协议的双向连接建立了理想化的情况，但是物联网概念的发起人似乎已经强调了一种更简便的RFID查询和应答模型。物联网和传感器网络是密不可分的，这个网络监控但不控制任何东西。与日常用品连接和传感器网络二者都使用共同的一套技术向着小型化，高效率的传感处理，以及无线通讯的方向发展。分析师通常这样描述两种不同的通信模式的物联网：人物通讯和物物通讯。(2)Thing-to-person(andperson-to-thing)communicationsencompassesanumberoftechnologiesandapplicationswhereinpeopleinteractwiththingsandviceversa,includingremoteaccesstoobjectsbyhumans,andobjects(sometimescalled“blogjects”)thatcontinuouslyreporttheirstatus,whereabouts,andsensordata.译文：人物（物人）通讯包含了许多人和物体相互进行技术和应用，反之亦然，包括人类远程访问物体，并不断报告对象（有时称为“blogjects”）他们的状态，行踪和传感器数据的技术。(3)Thing-to-thingcommunicationsencompassestechnologiesandapplicationswhereineverydayobjectsandinfrastructureinteractwithnohumanoriginator,recipient,orintermediary.Objectscanmonitorotherobjects,takecorrectiveactions,andnotifyorprompthumansasrequired.Machine-to-machinecommunicationisasubsetofthing-to-thingcommunication;butmachine-to-machinecommunicationoftenexistswithinlarge-scaleITsystemsandsoencompassesthingsthatmaynotqualifyas“everydayobjects”.译文：物物通信包括很多日常对象和基础设施的技术和应用，其中没有人类的发送者，收件者或中介。对象可以监视其他对象，采取纠正措施，并按照要求通知或提示人类。机器对机器的通信是物物通信的一个子集，但机器与机器之间的通信通常存在于大型的IT系统中，且其中的物体可能并不是“日常对象”。4.The word data warehouse was first developed by Bill Inmon in the early 1990s.He referred to it as being a integrated collection of information that could companies and organizations make better decisions.译文：数据仓库这个词最早在1990年代早期由Bill Inmon 提出的。他提到它是一个集成的信息集合，可以使公司和组织做出更好的决定。5.To be effective, a data warehouse had to be integrated ,subject oriented, non-volatile, and time variant. in this article, i will go over all these factors in detail. if you are building a data warehouse, it is important for you to understand why they are important.译文：为了使数据仓库有效,数据仓库必须具有集成性、面向主题、非易失性,和随时间变化的特性。在这篇文章中,我将详细讨论所有这些因素。如果您正在构建一个数据仓库,理解这些要素为什么重要对你来说是很重要的。 6.Being subject oriented means that the data will provide information about a specific subject rather than the information about the functions of a company. Because a data warehouse is subject oriented, it will allow you to analyze information that is connected to a specific subject. Being integrated means that the data that is collected within the data warehouse can come from different sources, but can be combined into one unit that is relevant and logical. Having a time-variant means that all the information within the data warehouse can be found with a given period of time. 译文：面向主题意味着数据仓库提供的数据将是有关特定主题的，而不是关于某一个公司的职能信息。由于数据仓库是面向主题的，它可以让你分析连接到某个特定主题的信息。集成性意味着在数据仓库中收集到的数据可以来自不同的来源，但也可以合并成到一个相关联且符合逻辑的单元中。随时间变化，表示该数据仓库内的所有的信息都可以在给定一个时间后被找到。 7. Currently, there are a number of ways that data is transferred from device to device. CDMA (code division multiple access) is one popular technology, and TDMA (time division multiple access) is a second. CDMA transfers a number of different data packets on one channel, using codes to distinguish between different receivers. TDMA, on the other hand, again uses one channel but allots each different data packet a time slot. 译文：目前，有许多的方式数据是从设备传送到设备的。 CDMA（码分多址）是一种流行的技术，和TDMA（时分多址）是另一种。 CDMA在一个信道上传输多个不同的数据分组，用不同的代码接收器之间进行区分。 TDMA，同样使用一个信道，但给每个不同的数据分组分配时隙。8.OFDMdiffersfromthesetechnologiessignificantly;thechannelitselfisdividedintonarrowbands,anddatapacketsaresentthrougheachbandindividually.Thismethodprovestobemuchmoreefficientthanthepreviouslyusedtechnologies,henceitisconsideredtobeanintegralpartofthe4Grevolution.译文：OFDM明显不同于这些技术;信道本身分为窄频带，并且数据分组通过每个频带分别发送。这种方法被证明比以前使用的技术更加高效，因此它被认为是4G革命的不可分割的一部分。9,”were well underway on the second year of GENI prototyping, GRNI Spiral 2,”Falk says. “One of our more exciting activities is what we are calling meso-scale deployments of virtualisable, programmable routers, switches, and WiMax base stations on 14 campuses and two national research backbone networks. Deployments like these are particularly exciting because theyll allow experimental applications and services built on GENI to directly reach real users on university campuses. Thus researchers will have the ability to build new services perhaps incompatible with the current interest- and test them at-scale with real end-users.” One area of concern is routing tables, which the nets backbone routers use to direct online traffic. The BGP (border gateway protocol ) routing table has grown hugely, doubling in size between 2003 and 2009, and there are concerns that if the level of growth continues, router hardware wont be able to cope. The IRTFs Routing Research Group(RRG ) is investigating alternatives, and its goal is to produce solid recommendations that the IETF can implement. Another related programs is Rochester Institute of Technologys Floating Cloud initiative, which hopes to address the problem of routing table growth by moving the routing tables from inside routers to network clouds. Initial testing took place on a dozen Linus boxes, and the next step is to try it on GENI.译文：“我们正在有条不紊地进行GENI原型研究的第二年，GRNI螺旋2，”福尔克说。 “我们的一个更令人兴奋的活动，就是我们正在呼吁在14校园和两个国家级科研骨干网进行，可编程路由器，交换机和WiMax基站的尺度虚拟部署。这样的部署是特别令人兴奋，因为他们将允许在GENI上建立试验性应用和服务从而直接到达大学校园里的真实用户。从而研究人员将有能力建立新的服务 - 或许与当前的利益是不相容的，在规模化的真实的终端用户中测设它们。“关注的一个领域是路由表网络上的骨干路由器用于转发在线流量。BGP（边界网关协议）的路由表已经增长的十分巨大，在2003年到2009年间的规模扩大了一倍，而且有人担心，如果增长水平继续下去，路由器的硬件将无法应付。IRTF的路由研究小组（RRG）正在研究替代方案，它的目标是创造出IETF可以实施的实体建议。另一个相关的项目是罗彻斯特理工学院的浮点云倡议，希望能通过将路由表从路由器内部移动到互联网云上来解决路由表的增长问题。最初的测试上在一些Linux操作系统上进行，下一步就是要在GENI进行尝试。9、Some time after a web page has been crawled by the search bot or crawler, the search engine then processes or indexes the page to determine what search words and phrases the page is relevant to as well as how relevant that page is compared with other web pages for those phrases. During this processing the search engine looks at many different factors including how many times each word and phrase occurs on the page, which words are in headings or bold, the domain name of the site, filename of the page, the pages that link to the page, and many more. 译文：网页在一段时间后就被搜索机器人或者爬虫捕获，接着搜索引擎处理或索引该页面以确定哪些搜索词和短语与该网页是相关的，以及对于那些短语，该网页相较于其他网页相关程度如何。在此处理过程中的搜索引擎着眼于许多不同的因素，包括在这个页面上每个单词或短语出现了多少次，哪些词语位于标题或是被加粗了，站点的域名，网页的文件名，页面链接的其他网页等等。10.An embedded system is any software system that must be designed on a platform different from the platform on which the system is intended to be deployed.译文：嵌入式系统是一种设计平台与运行平台不同的软件系统。11.what is meant by platform? On the development side, platform typically refers to an operating system capable of hosting software development, such as Windows, Solaris ,HP, etc. on the target side, the word platform refers to the devices on which the embedded system will be deployed.译文：平台是什么？对于开发者来说，平台指的是一种操作系统，能进行软件的开发工作，例如Windows，Solaris，HP操作系统等。对目标机来说，平台指的是一种设备，嵌入式软件能在上面部署运行。12.OK then, why the design constraint? Why arent embedded targets capable of hosting software development？ Because these targets are optimized for performance and/or simplicity, they lack equipment necessary for development (such as keyboard, monitors, networking, etc.) in general, development for the embedded environment is referred to as “cross-platform development”.译文：那好吧,为什么设计约束呢?为什么嵌入式目标不能够承载大规模的软件开发?因为这些目标为性能进行了优化和/或十分简单,他们发展开发所必需的设备(如键盘、显示器、网络等),一般来说,开发嵌入式环境称为“跨平台开发 13、The Private Eye, manufactured by Reflection Technology, is a LED based display that can produce a monochrome image at 720-780 resolution。It uses a vibrating mirror to create this image。 译文：私家侦探，是一个通过反射技术制造、可以摄制720-780分辨率的黑白图像，基于LED的显示屏，它使用振镜来产生图像。 14.The Twiddler, made by Handikey, is a one-handed chorded keyboard and mouse combination. It allows fairly rapid typing(up to 60 words a minute) in any body position.译文：Twiddler由Handikey制造,是一个单手弦线键盘和鼠标的组合。它允许你以任何体位相当快速地打字(一分钟60字以上) 15、At Cyrano Sciences, Inc. we are commercializing an electronic nose technology invented at the California Institute of Technology. This technology involves an array of sensors composed of polymers that are filled with conductive particles. When these sensors come in contact with a vapor, the polymer expands changing the resistance of the composite. This change in resistance is transmitted to a computer and the pattern derived from the sensor array is used to determine the type, quantity or quality of the odor that was sensed. This type of information is useful in a wide range of industries including the chemical, automotive, medical, petroleum, food, and fragrances.译文：在西拉诺科学公司，我们正在商业化一款使用加利福尼亚科技研究所发明的技术的电子鼻。这项技术涉及一组由导电粒子填充的聚合物的传感器，当这些传感器与蒸汽接触时，聚合物的膨胀改变了复合材料的电阻，这种电阻的变化被发送到一台计算机上，来自传感器阵列的图案被用于确定感应的气味的类型，数量或质量。这种类型的信息在许多行业中是有用的，包括化学，汽车，医疗，石油，食品和香料。16. our end product takes advantage of the fact that Pfinder follows the users position at all times. Borrowing this information, the speech-recognition system electronically “steers” an array of fixed microphones so that they reinforce only those sounds coming from the direction of the users mount. It is an easy job. Because sound travels at a fixed speed, it arrives at different locations at slightly different times. So each sound location yields a different pattern of time delays. Thus, if the system takes the outputs from a fixed array of microphones and adds then to time delays that characterize a certain location, it can reinforce the sound from that location. Then it need only compare the sound with those of known words until a match is found.译文：我们的最终产品利用Pfinder始终跟随用户的位置这一事实。借助这一点,语音识别系统电子“引导”一组固定麦克风,以便只加强那些来自用户安装方向传来的声音。这是一个简单的工作。因为声音以一个固定的速度传播,它在不同的时间到达不同的地方。所以每个声音的位置产生不同模式的时间延迟。因此,如果系统需要从一组固定麦克风输出并增加时间延迟来描述一个特定的位置,它可以加强这一位置的声音。然后只需要将声音与已知的单词进行直到找到一个匹配的。 17.One such standard is MPEG-4 from the Moving Picture Expert Group, which allows the compression of different objects in a scene with