英语口语准确翻译.doc

第一章Electronic amplifiers are used mainly to increase the voltage , current ,or power of a signal . 电子放大器主要是用来增强电压，电流或信号（信号功率）的强度A linear amplifier provides signal amplification with little or no distortion , so that the output is proportional to the input .线性的放大器能几乎无失真地放大信号，从而使输出与输入相称 A nonlinear amplifier may produce a considerable change in the waveform of the signal .非线性放大器在信号的波形方面会产生相当大的变动 Linear amplifiers are used for audio and video signals , whereas nonlinear amplifier find use in oscillators , power electronics , modulators , mixers , logic circuits , and other applications where an amplitude cutoff is desired . 线性放大器用于音频信号，而非线性放大器用于振荡器，电力电子学，调节器，混音器，逻辑电路以及其他的要求振幅中断的器材Although vacuum tubes played a major role in amplifiers in the past , today either discrete transistor circuits or integrated circuits are mostly used .尽管真空管在过去的放大器中充当了主要的角色，而如今最常用的是离散的晶体管电路或集成电路第二章Configurable computing is still an extremely young field .可配置计算仍然是极年轻的领域 Although Gerald Estrin of the University of California at Los Angeles proposed configurable computing in the late 1960s , the first demonstrations did not occur until a few years ago , and current FPGAs ,with up to 100,000 logic elements , still do not come close to exploiting the full possibilities of the technique . 虽然可配置计算是由洛杉矶加州大学的杰拉尔德艾斯特林在1960年代末期提出的，但是在几年前才首次展示给世人，甚至，含有十万个逻辑元件的电流FPGA（现场可编程门阵列）仍未能开发出其技术的全部潜力Future FPGAs will be much larger , as with many other integrated circuits , the number of elements on a single FPGA has doubled roughly every 18 months . 正如许多其他的集成电路一样，未来的FPGA会（比目前的）大的多,单一的FPGA中的元件的数量约每隔一年半就会翻倍。 Before the decade is out , we expect to see FPGAs that have a million logic elements .十年之后，我们期盼着会出现含有一百万个逻辑元件的FPGA Such chips will have much broader application , including highly complex communications and signal-processing algorithms .这些芯片应用范围更广，包括应用于高度合成的通讯系统和信号加工算法。第三章Variable-length instructions are more difficult for a chip to process , though , and the longer CISC instructions are especially complex . 可变长度指令使芯片更难处理，而较长的CISC（复杂指令集计算）指令特别复杂。Nonetheless , to maintain software compatibility , modern chips such as Intels Pentium III and Advanced Micro Devices Inc.s Athlon must still work with all troublesome CISC instructions that were designed in the 1980s , even though their original advantage-memory conservation-isnt as important .尽管如此，为了维持软件兼容性，诸如英特尔奔腾3和AMD公司（高级微设备公司）的速龙这样的现代芯片，虽然它们最初的优势存储保护不是那么重要，但都还是用1980年代设计的令人费劲的CISC指令处理。第四章The TCP/IP (Transmission Control Protocol/Internet Protocol) protocol suite supports the Internet , the single largest computer network in the world .TCP/IP（传输控制协议/互联网协议）支持全世界单个最大计算机网络，也即是互联网。 The Internet is not a single network .Rather ,it is an internet consisting of many smaller networks .互联网不是单个的网络，而是由许许多多更小的网络组成的。The Internet (note the definite article and the capital “I”) is unique for it contains more than 11000 networks and a million hosts .互联网（注意定冠词和大写的“I”）是唯一的，因为它包括了11000多个网络和一百万个主机。 It is a multiprotocol internet , since protocol suites other than TCP/IP also are used .协议套房除了TCP / IP也使用，所以这是个多重协议的因特网 However , the TCP/IP protocol is by far the most widely used .但在目前最普遍使用的还是TCP/IP协议。第五章A number of biometric characteristics exist and are in use in various applications (see Figure 1) .许多的生物计量特征存在和正使用于各种各样的应用程序中。（详见图形1） Each biometric has its strengths and weaknesses , and the choice depends on the application .每个生物计量都有其各自的优劣势，这选择取决于它们的应用程序 No single biometric is expected to effectively meet the requirements of all the applications . 并非单个生物计量都能如愿且有效地满足所有应用程序的要求的。In other words , no biometric is “optimal” .换言之，没有生物计量是最理想的。 The match between a specific biometric and an application is determined depending upon the operational mode of the application and the properties of the biometric characteristic .决定某个特定的生物计量和某个应用程序间是否匹配取决于应用程序的运作模式和生物计量的性能。A brief introduction of the commonly used biometrics is given below .如下会给出常用生物统计学的简单介绍。第六章Ideally , humans can hear sounds that fall within a frequency range of 20 HZ to 20 kHZ . 理想上，人们能听到频率在20到20000赫兹之内的声音。 As we age , our ability to hear high-frequency sounds diminishes , so its fair to say that adults can hear sounds as high as 10 kHZ to 15 kHZ .当我们变老时，我们听高频声音的能力相应减弱，因此，说成人能听到10到15000赫兹间的声音是一点也不夸张的。 You might think that since we can only hear frequencies up to a certain frequency , a 22 kHZ sampling rate would be more than enough . The truth is , unfortunately , a little more complicated .你可能会认为既然我们只能听到某一定频率到某一特定频率（间的声音），那么22000赫兹的采样率是绰绰有余的。很遗憾，事实上是更复杂些。第七章The face retrieval problem , known as face detection , can be defined as follows :人脸检索问题也即人们常说的人脸检测可定义如下： given an arbitrary black and white , still image , find the location and size of every human face it contains . 考虑到这其中任意的黑白片静态影像，以及要寻找每张脸的拍摄场地和它们的尺寸大小。There are many applications in which human face detection plays a very important role :（就需要）很多程序在人脸检测方面发挥重要作用。 it represents the first step in a fully automatic face recognition system , and it can be used in image database indexing searching by content , in surveillance system and in human-computer interfaces . 它采用了全自动的人脸识别系统描绘了第一个步骤，还可用于按内容搜索的影像数据库检索中以及监视系统和人机界面（方面上）It also provides insight on how to approach other pattern recognition problems involving deformable textured objects . At the same time , it is one of the harder problems in pattern recognition . 它甚至能使人深入了解如何处理另外的一些涉及可变形的有织纹的物体类的模式识别问题。同时，这也是一种更难的模式识别第八章The optical system of a television camera include a fixed lens that is used to focus the scence onto the front of the pickup device . 采用光学系统的摄像机包括一个固定的镜头，这个镜头能用于聚焦场景于摄取装置前。Color cameras also have a system of prisms and mirrors that separate incoming light from a scene into the three primary colors : red , green , and blue .彩色摄像机有个棱镜和反光镜系统可分解场景的入射光线为三原色，即：红绿蓝。 Each beam of light is then directed to its own pickup device . 然后每个光束指向各自的摄取装置Almost any color can be reproduced by combining these colors in the appropriate proportions .以适当比例结合这些颜色，几乎任何色彩都能重制出来Most inexpensive consumer video cameras use a filter that breaks light from an image into the three primary colors . 大多便宜的消费者视频摄像机会用过滤器把光从影像中分解成三原色。第九章Telecommunications are the transmission of words , image or data in the form of electronic or electromagnetic signals or impulses .通讯便是以电子信号或电磁脉冲的形式传输文字，影像或数据的传动装置。 Transmission media include the telephone (using wire or optical cable) , radio , television , microwave , and satellite .传送介质包括电话（使用线缆或光缆），收音机，电视，微波和卫星Data communication , the fastest growing field of telecommunication , is the process of transmitting data in digital form by wire or radio .在通信领域发展最为迅速的数据通信是通过有线或无线地以数字形式传送数据的过程。第十章第十二章As of March 1994 , 24 GPS satellites were in operation . Replenishment satellites are ready for launch , and contracts have been awarded to provide satellites into the 21st century .自1994年3月，24全球定位系统卫星开始运转以来，备用卫星时刻准备发射，并拟好了在21世纪允许卫星运行的合同 GPS applications continue to grow in land , sea , air , and space navigation . 全球定位系统程序在海陆空及外太空都持续增加The ability to enhance safety and to decrease fuel consumption will make GPS for landing at fogbound airports . 提高安全性的能力和减少能耗将会使GPS能应用于雾天的飞行着陆Automobiles will use GPS as part of intelligent transportation systems . 汽车会将GPS作为智能交通系统的一部分Emerging technologies will enable GPS to determine not only the position of a vehicle but also its altitude . 新兴技术使GPS不仅能定位交通工具，还能定位它们的高度第十三章Artificial intelligence is scarely younger than conventional computer science , the beginnings of AI can be seen in the first game-playing and puzzle-solving programs written shortly after World War II . 人工智能并无早于传统的计算机科学的出现，人工智能的初期可见于首次的游戏竞技和解迷程序，这些程序编于二战结束不久。Game-playing and puzzle-solving may seem somewhat remote from expert systems , and insufficiently serious to provide a theoretical basis for real applications . 电子竞技和解谜可能与专家系统有点遥远，且不能为实时程序提供理论基础However , a rather basic notion about computer-based problem solving can be traced back to early attempts to program computers to perform such tasks .但是，一个关于解决基于计算机问题的基本概念要追溯到程序计算机执行这些任务的早期尝试第十四章Imagine a house that always knows where your kids are and tells you if they are getting into trouble .假设有这么个房子，它总是能知道你孩子在哪并告诉你孩子们是否有麻烦。 Or an office that sees when you are having an important meeting and shields you from interruptions Or a car that senses when you are tired and warns you to pull over . 或者有那么一个办公室，它能知道你什么时候会有重要的会议并保证你不受打扰。抑或有那么一辆车，它能感觉到你何时会疲倦并警告你停车。Scientists have long tried to design computer systems that could accomplish such feats . 科学家曾长时间尝试设计一种能实现拥有这些特技的计算机系统。Despite their efforts , mordern machines are still no match for baby-sitters or secretaries . But they could be . 尽管科学家们做了很多努力，仍未能找到与保姆和秘书相匹配的现代设备第十五章Training the neural