最新计算机专业英语的课文与翻译

Unit 8 Computer Networking

Text 1 Data Communications

The end equipment can be computers, printers, keyboards, CRTs, and so on.They are either generates the digital information for transmission or uses the received digital data. This equipment generally operates digital information internally in word units.

DTE is data terminal equipment. A station controller (STACO)is the corresponding unit at the secondaries. At one time, the DTE was the last piece of equipment that belonged to the subscriber in a data link system. Between the DTEs, first is the modem, and then is the communications equipment. The communication equipment is owned and maintained by Telco. Data communications equipment (DCE) accepts the serial data stream from the DTE. And DCE converts it to some form of analog signal suitable for transmission on voice-grade lines. At the receive end, the DCE performs the reverse function. It converts the received analog signal to a serial digital data stream. The simplest form of DCE is a modem (modulator/demodulator) or data set. At the transmit end, the modem can be considered a form of digital-to-analog converter.While at the receive end, it can be considered a form of analog-to-digital converter.

参考译文

数据通信

终端设备可以是计算机、打印机、键盘、CRT等。它们可以生成要发送的数字信息，也可以使用所接收的数字数据。这种设备通常在内部以字为单位处理数字信息。

DTE一般称为数据终端设备。辅助设备一方的相应设备是工作站控制器（STACO）。同时，DTE也是数据链路系统中属于用户端的最后一个设备。在两个DTE之间，先是调制解调器，接着是属于Telco电话公司维护的通信设备。数据通信设备（DCE）从DTE接收串行数据流，并将其转换成适合于在语音线路上发送的某种模拟信号形式。在接收端，DCE完成相反的功能，把接收到的模拟信号转换成串行数字数据流。最简单的DCE是调制解调器或数据传送机。在发送端，调制解调器可以视为一种数/模转换器，而在接收端则可视为一种模／数转换器。

Text 2 Architecture of Computer Networks

Computer network is a complex unit, it consists of two or more connected computing units. It is used for the purpose of data communication and resource sharing. Design of a network and its logical structure should comply with a set of design principles. They include: the organization of functions, the description of data formats and procedure.

In the following two sections we will discuss two important network architectures, the OSI reference model and the TCP/IP reference model.

(1)the OSI reference model

The OSI (open systems interconnection) model was created by the ISO. This model is a foundation for comparing protocols; However, more protocols deviate from the rules set up by the OSI model.

The OSI model has seven layers. Note that the OSI model itself is not a network architecture.

It just tells what each layer should do. However, ISO has also produced standards for all the layers. Each one has been published as a separate international standard.

(2)the TCP/IP reference model

TCP/IP is a communication protocol; it provides many different networking services.

The TCP/IP Internet protocol suite is formed from two standards: the TCP (Transmission Control Protocol) and the IP (Internet Protocol). TCP means it is on the transport layer. IP means it is on the network layer. On top of the transport layer is the application layer. It contains all the higher-level protocols. The early ones included virtual terminal (TELNET), file transfer (FTP), electronic mail (SMTP)and domain name service (DNS).

As we know, TCP/IP is the foundation of the Internet.These protocols are continually changing and evolving to support the needs of the user community.

参考译文

计算机网络结构

计算机网络是由两个或多个计算机设备互连而成的一种复合系统，它用于数据通信和资源共享。网络设计及其逻辑结构应该遵循一套设计原则，其中包括：功能的组织以及数据格式和过程的说明。

在下面的两小节里，我们将讨论两个重要的网络体系结构，即OSI参考模型和TCP/IP 参考模型。

(1)OSI参考模型

OSI模型（开放系统互联参考模型）是由国际标准化组织（ISO）开发的一个建议。相对于其他协议来说，此种模式为基础模式。然而，更多的协议是背离OSI模型的。

OSI模型有7层。应该注意的是，OSI模型本身并不是一种网络体系结构，它只是说明每一层应该做什么。然而，ISO还是对各层制定了标准，每一层都是作为一个单独的国际标准来颁布的。

(2)TCP/IP参考模型

TCP/IP参考模型是一种传输协议，提供了许多不同的网络服务。

TCP/IP协议组由TCP（传输控制协议）和IP（网际协议）两部分组成。TCP表明是处于传输层，IP意为是在网络层。在传输层上面是应用层。应用层包括所有高层协议。早期的协议包括虚拟终端TELNET、文件传送协议FTP、电子邮件SMTP和域名服务DNS。

现在我们知道，TCP/IP协议是因特网的基础。这些协议在用户们的支持下不断地改变和进化着。

Text 3 Local Area Network

A LAN (Local area data network) is a group of computers. The work devices connected together usually within the same building. By definition, the connections must be high-speed and relatively inexpensive (e.g. token ring or Ethernet). For example, a LAN may be used to interconnect workstations distributed around offices within a single building or a group of buildings such as a university campus.

LANs consist of carefully selected groups of components (hardware and software). They are configured for the specific requirements of the organization. A LAN is generally limited to the size of a department or an organization. And a LAN often consists of 2 to 100 devices. LANs usually contain resources such as servers, printers, and connections to other networks through

internetworking devices. The internetworking devices include switches and routers.

In the next section we will discuss the structure of the different types of LAN.

(1)Topology

Most wide area networks, such as the PSTN, use a mesh (sometimes referred to as a network) topology.With LANs, however, the limited physical separation of the subscriber DTEs allows simpler topologies to be used. The four topologies in common use are star, bus, ring and hub.

The most widespread topology for LANs designed to function as data communication subnetworks for the interconnection of local computer-based equipment is the hub topology. It is a variation of the bus and ring.

(2)Transmission media

Twisted pair, coaxial cable and optical fibre are the three main types of transmission medium used for LANs.

(3)Medium access control methods

Two techniques have been adopted for use of the medium access control in the LANs. One is carrier-sense-multiple-access with collision detection, and the other is control token.

参考译文

局域网

局域数据网(局域网)由若干计算机组成。通常是一幢楼内的工作设备被连接在一起。通过定义可知，这种连接一定是高速并且相对廉价的（如：令牌网和以太网）。例如，一个局域网可以把一幢楼里或像大学校园内楼群里的各个办公室的工作站连在一起。

局域网是由精心挑选的各组设备（硬件和软件）构成的。它们根据组织的各种特殊需要来配置。局域网的大小一般限制在一个部门或者一个组织，由2～100台电脑组成。局域网经常包含一些资源，如一些服务器和打印机，而且可以通过网络设备与其他的网络连接。这些网络设备包括交换机和路由器等。

接下来，我们将讨论不同类型局域网的结构。

(1)拓扑结构

大多数广域网，如公共电话交换网（PSTN），使用网状（有时称为网络）拓扑结构；而局域网由于用户数据终端设备相距很近，可采用简单的拓扑结构。常用的有星形、总线、环形和集线器等4种拓扑结构。

应用最广的、用于互连本部门计算机设备以进行数据通信的局域网拓扑结构是集线器拓扑结构。这种拓扑结构是总线和环形拓扑结构的变种。

(2)传输媒体

双绞线、同轴电缆和光纤是局域网采用的3种主要传输媒体。

(3)媒体访问控制方法

局域网中采用了两种媒体访问控制技术，一种是载波侦听多路访问／冲突检测技术（CSMA/CD），另一种是令牌控制技术。

Text 4 Internet

The Internet is used by millions of people across the world to communicate business and personal information. The Internet is huge. Then we will talk about the difference of “an internet”and “ the Internet”.

An internet (note the lower case "i") is a computer network. It allows computers with

distinctive software and hardware to communicate. Many kinds of computers can be connected to an internet. Each computer can serve a specialized role. It offers a wide variety of services to its users.

The Internet is specific kind of internet. In The Internet Passport, the Internet will be defined as the network of networks. It follows a set of rules known as the "Internet Protocol (IP) suite".

But what does this mean to you? It means that any computer that is connected to the Internet can communicate with any other Internet computer. From the user's perspective, this works much like the telephone system works. You can dial from your phone to any other phone on the system, no matter what kind of telephone you have; you only need to know the phone number of the person you want to reach.

With an Internet connection you can get some of the basic services available are:

?E-mail. It’s a fast, easy, and inexpensive way to communicate with other Internet users around the world.

?Telnet. It allows a user to log into a remote computer as though it were a local system.

?FTP. It allows a user to transfer virtually every kind of file that can be stored on a computer from one Internet-connected computer to another.

?Usenet news. It’s a distributed bulletin board which offers a combination news and discussion service on thousands of topics.

?World Wide Web (WWW). It’s a hypertext interface to Internet information resources. Also, through an Internet connection, you can:

?access online library catalogs.

?copy computer files or software from archives.

?access databases for teaching or research.

?obtain free electronic books.

?use educational and information services.

?use directory services to find Internet users.

?access supercomputer sites.

It was estimated that at this rapid growth everyone in the world would have an e-mail address in the near future.

参考译文

互联网

因特网是世界上很多人用来进行商业贸易和个人信息交流的网络，它非常巨大。接下来，我们将讨论互联网及因特网。

互联网(internet)（注意小写字母i）是一种计算机网络，该网络上的计算机在通信时可以使用不同的软件和硬件。多种计算机都可以连入互联网，每台计算机都可以有一独特作用。一个互联网可以向它的用户提供各式各样的业务。

因特网(Internet)是一种专用互联网。因特网在它的证书中定义为网络的网络，该网络使用了一组叫做互联网协议（IP）组的规则。

但对你来说，这意味着什么呢？这表明连接到因特网上的计算机可以与因特网上任何其他计算机通信。从用户的角度来看，其工作方式很像电话系统的工作方式。在电话系统内，可以从你的电话机拨打任何其他电话，而不管你使用什么样的电话机，你只需知道对方的电

话号码即可。

你可以通过因特网得到的基本服务如下：

?电子邮件。它是与世界范围内的因特网用户进行联系的一种快速、方便、廉价的交流方式。

?远程登录。允许用户连接到远程计算机上，就像这台远程计算机是本地机一样。

?文件传输协议。该协议可以将存储在计算机上的各种文件，从因特网上的一台计算机传送给另一台计算机。

?新闻组网络系统。一种分布式的电子公告牌，它能提供有关上千种话题的新闻和讨论服务。

?万维网。一种因特网信息资源的超文本界面。

?访问在线图书馆目录。

?

?从计算机档案库存储器中拷贝文件或软件。

?访问教学或科研数据库。

?

?获取免费电子图书。

?

?使用教育和信息服务。

?

?使用目录服务以查找因特网用户。

?访问超级计算机站点。

估计以这样的高速发展，在不久的将来世界上每个人都将拥有至少一个电子邮件地址。

Text 5 The World Wide Web

The World Wide Web (also known as WWW or Web) is one of the fastest-growing Internet software applications. It is an architectural framework. It linked documents spread out over thousands of machines for accessing all over the Internet.

The World Wide Web ties the computers together into a vast collection of interactive multimedia resources. The WWW is a way of exchange information between computers on the Internet.

The Web is built around hypertext and hypermedia. A hypertext document has certain keywords or phrases linked to other online documents. A person reading a hypertext document about mobile phone, for example, might be able to select the highlighted word “Nokia 3310”, and he call up another document giving more information about that particular type. With documents intertwined by links into a web of information, you can select paths to browse online resources, a process often referred to as surfing.

Hypermedia extends the concept of hypertext to other forms of information. They include: images, sounds, and even video clips. If a person read a hypermedia document about mobile phones, then he might select a video show of a phone and hear the ring of it.

The World Wide Web also subsumes previous Internet information systems such as Gopher

and FTP. These resources can still be accessed through the Web. But the Web offered by these more restricted connection methods. Now the Web provides a wealth of additional capabilities.

Thousands of computers around the world are now connected to the Web. They offer a huge variety of information and services to visitors. These online documents are generally referred to as pages. They are composed and supported by various people and organizations. Web pages are available for an amazing variety of tasks ranging from the playful to the serious. You can get many services access Web pages. For example, you can search database of mailing lists, you can see pictures of your favorite band and their concert schedule, or you can take a “tour”through a foreign country. Thousands of links to new services are added to the Web each day, and its growth has been explosive.

参考译文

万维网

万维网（又称WWW或Web）是因特网上发展最快的应用软件之一。它是一种结构化框架，用于访问遍布在因特网上的成千上万台机器中的链接文档。

万维网把这些计算机连接成了一个巨大的交互式多媒体资源库，它是因特网上的计算机之间进行信息交流的一种方式。

Web是用超文本和超媒体设计的。超文本文档中的一些关键词或短语被链接到了其他的在线文档中。例如，某人在阅读一篇有关移动电话的超文本文档时，如果他选择高亮显示的词“诺基亚3310”，就能链接到另一篇有关这一类型移动电话的文章，从而可以获取更多的信息。网络文章通过链接形成了一个网络信息资源库，用户可以选择路径来浏览这些在线资源，这种行为通常被称为“网上冲浪”。

超媒体将超文本的概念扩展到了其他的信息形式，其中包括图片、声音，甚至是录像剪辑。在超媒体文档中阅读有关移动电话的文章时，读者可以选择关于该电话的视频演示，还能听见铃声。

万维网也包括了以前的因特网信息系统，如Gopher 和FTP。这些资源仍然可以通过网络访问，但是以前那些连接方式的局限性很大，现在的网络提供了许多先辈们没能提供的功能。

现在世界上成千上万的计算机都连接到了网络上，而且为访问者提供了相当多的信息和服务。这些由不同的人和组织编写和支持的在线文档被称为网页。Web网页可以跨越从诙谐到严肃的各种风格。通过访问网页，用户可以查看邮件数据库，查阅自己喜爱的乐队的图片和他们的演出时间表，或去国外周游一圈。现在每天都会增加上千种新的服务链接，万维网已经飞速发展起来了。

计算机专业英语翻译

国家计算机教育认证 计算机英语 计算机英语词汇对译 蒙阴高新电脑学校 资料整理：孙波 IT CFAC gaoxindiannaoxuexiao

2010年9月1日

?PC personal computer 个人计算机 ?IBM International Business Machine 美国国际商用机器公司的公司简称，是最早推出的个人 计算机品牌。 ?Intel 美国英特尔公司，以生产CPU芯片著称。 ?Pentium Intel公司生产的586 CPU芯片,中文译名为“奔腾”。 ?Address地址 ?Agents代理 ?Analog signals模拟信号 ?Applets程序 ?Asynchronous communications port异步通信端口 ?Attachment附件 ?Access time存取时间 ?access存取 ?accuracy准确性 ?ad network cookies广告网络信息记录软件 ?Add-ons 插件 ?Active-matrix主动矩阵 ?Adapter cards适配卡 ?Advanced application高级应用 ?Analytical graph分析图表 ?Analyze分析 ?Animations动画 ?Application software 应用软件 ?Arithmetic operations算术运算 ?Audio-output device音频输出设备 ?Basic application基础程序 ?Binary coding schemes二进制译码方案 ?Binary system二进制系统 ?Bit比特 ?Browser浏览器 ?Bus line总线 ?Backup tape cartridge units备份磁带盒单元 ?Business-to-consumer企业对消费者 ?Bar code条形码 ?Bar code reader条形码读卡器 ?Bus总线 ?Bandwidth带宽 ?Bluetooth蓝牙 ?Broadband宽带 ?Business-to-business企业对企业电子商务 ?cookies-cutter programs信息记录截取程序 ?cookies信息记录程序

现代大学英语精读book4-unit6课文

Book 4-Unit 5 Text A The Telephone Anwar F. Accawi 1.When I was growing up in Magdaluna, a small Lebanese village in the terraced, rocky mountains east of Sidon, time didn't mean much to anybody, except maybe to those who were dying. In those days, there was no real need for a calendar or a watch to keep track of the hours, days, months, and years. We knew what to do and when to do it, just as the Iraqi geese knew when to fly north, driven by the hot wind that blew in from the desert. The only timepiece we had need of then was the sun. It rose and set, and the seasons rolled by and we sowed seed and harvested and ate and played and married our cousins and had babies who got whooping cough and chickenpox—and those children who survived grew up and married their cousins and had babies who got whooping cough and chickenpox. We lived and loved and toiled and died without ever needing to know what year it was, or even the time of day. 2.It wasn't that we had no system for keeping track of time and of the important events in our lives. But ours was a natural or, rather, a divine—calendar, because it was framed by acts of God: earthquakes and droughts and floods and locusts and pestilences. Simple as our calendar was, it worked just fine for us. 3.Take, for example, the birth date of Teta Im Khalil, the oldest woman in Magdaluna and all the surrounding villages. When I asked Grandma, "How old is Teta Im Khalil" 4.Grandma had to think for a moment; then she said, "I've been told that Teta was born shortly after the big snow that caused the roof on the mayor's house to cave in."

土木工程外文文献及翻译

本科毕业设计 外文文献及译文 文献、资料题目：Designing Against Fire Of Building 文献、资料来源：国道数据库 文献、资料发表（出版）日期：2008.3.25 院（部）：土木工程学院 专业：土木工程 班级：土木辅修091 姓名：武建伟 学号：2008121008 指导教师：周学军、李相云 翻译日期： 20012.6.1

外文文献: Designing Against Fire Of Buliding John Lynch ABSTRACT: This paper considers the design of buildings for fire safety. It is found that fire and the associ- ated effects on buildings is significantly different to other forms of loading such as gravity live loads, wind and earthquakes and their respective effects on the building structure. Fire events are derived from the human activities within buildings or from the malfunction of mechanical and electrical equipment provided within buildings to achieve a serviceable environment. It is therefore possible to directly influence the rate of fire starts within buildings by changing human behaviour, improved maintenance and improved design of mechanical and electrical systems. Furthermore, should a fire develops, it is possible to directly influence the resulting fire severity by the incorporation of fire safety systems such as sprinklers and to provide measures within the building to enable safer egress from the building. The ability to influence the rate of fire starts and the resulting fire severity is unique to the consideration of fire within buildings since other loads such as wind and earthquakes are directly a function of nature. The possible approaches for designing a building for fire safety are presented using an example of a multi-storey building constructed over a railway line. The design of both the transfer structure supporting the building over the railway and the levels above the transfer structure are considered in the context of current regulatory requirements. The principles and assumptions associ- ated with various approaches are discussed. 1 INTRODUCTION Other papers presented in this series consider the design of buildings for gravity loads, wind and earthquakes.The design of buildings against such load effects is to a large extent covered by engineering based standards referenced by the building regulations. This is not the case, to nearly the same extent, in the

计算机专业英语2008影印版选择题的翻译加答案

CHAPTER 1 1、A common term that describes the combination of traditional computer and communication technologies is b. information technology 一个描述了传统的计算机和通信技术结合的常见的术语 B.信息技术 2、Procedures are typically documented in manuals written by b. computer specialists 程序一般是___在手册撰写记录的 B.计算机专家 3、Which of the following is an example of connectivity? a. Internet 下列哪一项是连接的一个例子吗？ A.互联网 4、Windows XP, windows Vista, and Macintosh OS X are all examples of b. operating systems Windows XP，Windows Vista，和Macintosh OS X都是__的例子 B.操作系统 5、Because of their size and cost, these computers are relatively rare. d. supercomputers 由于它们的尺寸和成本，这些电脑是比较少见的。 D.超级计算机 6、The system component that controls and manipulates data in order to produce information is called the d. microprocessor 系统组成，控制和操纵数据来产生信息称为 D.微处理器 7、A system component that translates data and programs that humans can understand into a form that the computer can process is called a(n) c. output device 一个系统组件，将人类可以理解成计算机能够处理的形式的数据和程序被称为 C.输出设备 8、A CD is an example of a(n) c. optical disc CD是___的简称 C.光盘 9、If you want to communicate a message or persuade other people, you would typically use this type of software. d. presentation 如果你想传达信息或说服别人，你通常会使用这种类型的软件。 D.演示 10、Many experts are predicting that this revolution is expected to dramatically affect the way we communicate and use computer technology. d. wireless

现代大学英语精读2课文

Unit1 Another School Year — What For Let me tell you one of the earliest disasters in my career as a teacher. It was January of 1940 and I was fresh out of graduate school starting my first semester at the University of Kansas City. Part of the student body was a beanpole with hair on top who came into my class, sat down, folded his arms, and looked at me as if to say "All right, teach me something." Two weeks later we started Hamlet. Three weeks later he came into my office with his hands on his hips. "Look," he said, "I came here to be a pharmacist. Why do I have to read this stuff" And not having a book of his own to point to, he pointed to mine which was lying on the desk. New as I was to the faculty, I could have told this specimen a number of things. I could have pointed out that he had enrolled, not in a drugstore-mechanics school, but in a college and that at the end of his course meant to reach for a scroll that read Bachelor of Science. It would not read: Qualified Pill-Grinding Technician. It would certify that he had specialized in pharmacy, but it would further certify that he had been exposed to some of the ideas mankind has generated within its history. That is to say, he had not entered a technical training school but a university and in universities students enroll for both training and education.

土木工程外文文献翻译

专业资料 学院： 专业：土木工程 姓名： 学号： 外文出处：Structural Systems to resist (用外文写) Lateral loads 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 抗侧向荷载的结构体系 常用的结构体系 若已测出荷载量达数千万磅重，那么在高层建筑设计中就没有多少可以进行极其复杂的构思余地了。确实，较好的高层建筑普遍具有构思简单、表现明晰的特点。 这并不是说没有进行宏观构思的余地。实际上，正是因为有了这种宏观的构思，新奇的高层建筑体系才得以发展，可能更重要的是：几年以前才出现的一些新概念在今天的技术中已经变得平常了。 如果忽略一些与建筑材料密切相关的概念不谈，高层建筑里最为常用的结构体系便可分为如下几类： 1.抗弯矩框架。 2.支撑框架，包括偏心支撑框架。 3.剪力墙，包括钢板剪力墙。 4.筒中框架。 5.筒中筒结构。 6.核心交互结构。 7. 框格体系或束筒体系。 特别是由于最近趋向于更复杂的建筑形式，同时也需要增加刚度以抵抗几力和地震力，大多数高层建筑都具有由框架、支撑构架、剪力墙和相关体系相结合而构成的体系。而且，就较高的建筑物而言，大多数都是由交互式构件组成三维陈列。 将这些构件结合起来的方法正是高层建筑设计方法的本质。其结合方式需要在考虑环境、功能和费用后再发展，以便提供促使建筑发展达到新高度的有效结构。这并

不是说富于想象力的结构设计就能够创造出伟大建筑。正相反，有许多例优美的建筑仅得到结构工程师适当的支持就被创造出来了，然而，如果没有天赋甚厚的建筑师的创造力的指导，那么，得以发展的就只能是好的结构，并非是伟大的建筑。无论如何，要想创造出高层建筑真正非凡的设计，两者都需要最好的。 虽然在文献中通常可以见到有关这七种体系的全面性讨论，但是在这里还值得进一步讨论。设计方法的本质贯穿于整个讨论。设计方法的本质贯穿于整个讨论中。 抗弯矩框架 抗弯矩框架也许是低，中高度的建筑中常用的体系，它具有线性水平构件和垂直构件在接头处基本刚接之特点。这种框架用作独立的体系，或者和其他体系结合起来使用，以便提供所需要水平荷载抵抗力。对于较高的高层建筑，可能会发现该本系不宜作为独立体系，这是因为在侧向力的作用下难以调动足够的刚度。 我们可以利用STRESS，STRUDL 或者其他大量合适的计算机程序进行结构分析。所谓的门架法分析或悬臂法分析在当今的技术中无一席之地，由于柱梁节点固有柔性，并且由于初步设计应该力求突出体系的弱点，所以在初析中使用框架的中心距尺寸设计是司空惯的。当然，在设计的后期阶段，实际地评价结点的变形很有必要。 支撑框架 支撑框架实际上刚度比抗弯矩框架强，在高层建筑中也得到更广泛的应用。这种体系以其结点处铰接或则接的线性水平构件、垂直构件和斜撑构件而具特色，它通常与其他体系共同用于较高的建筑，并且作为一种独立的体系用在低、中高度的建筑中。

计算机专业英语课文翻译部分(第四版)

1.2 总线互连 总线是连接两个或多个设备的通信通路。总线的关键特征是，它是一条共享传输介质。多个设备连接到总线上，任一个设备发出的信号可以为其他所有连接到总线上的设备所接收。如果两个设备同时传送，它们的信号将会重叠，引起混淆。因此，一次只能有一个设备成功地（利用总线）发送数据。 典型的情况是，总线由多条通信通路或线路组成，每条线(路)能够传送代表二进制1和0的信号。一段时间里，一条线能传送一串二进制数字。总线的几条线放在一起能同时并行传送二进制数字。例如, 一个8位的数据能在8条总线线上传送。 计算机系统包含有多种不同的总线，它们在计算机系统层次结构的各个层次提供部件之间的通路。连接主要计算机部件(处理机, 存储器, I/O)的总线称为系统总线。系统总线通常由50~100条分立的(导)线组成。每条线被赋予一个特定的含义或功能。虽然有许多不同的总线设计，但任何总线上的线都可以分成三个功能组：数据线、地址线和控制线。此外可能还有为连接的模块提供电源的电源线。 数据线提供系统模块间传送数据的路径，这些线组合在一起称为数据总线。典型的数据总线包含8、16或32根线，线的数量称为数据总线的宽度。因为每条线每次传送1位，所以线的数目决定了每次能同时传送多少位。数据总线的宽度是决定系统总体性能的关键因素。 地址线用于指定数据总线上数据的来源和去向。例如，如果处理机希望从存储器中读一个字的数据，它将所需要字的地址放在地址线上。显然，地址总线的宽度决定了系统最大可能的存储器容量。 控制线用来控制对数据线和地址线的访问和使用。由于数据线和地址线被所有部件共享，因此必须用一种方法来控制它们的使用。控制信号在系统模块之间传送命令和定时信息。定时信息指定了数据和地址信息的有效性，命令信号指定了要执行的操作。 大多数计算机系统使用多总线，这些总线通常设计成层次结构。图1.3显示了一个典型的高性能体系结构。一条局部总线把处理机连接到高速缓存控制器，而高速缓存控制器又连接到支持主存储器的系统总线上。高速缓存控制器集成到连接高速总线的桥中。这一总线支持连接到：高速LAN、视频和图形工作站控制器，以及包括SCSI 和FireWire的局部外设总线的接口控制器。低速设备仍然由分开的扩充总线支持，用一个接口来缓冲该扩充总线和高速总线之间的通信流量。 PCI 外部设备互连是流行的高带宽的、独立于处理机的总线，它能够作为中间层或外围设备总线。当前的标准允许在66MHz频率下使用多达64根数据线，其原始传输速率为528MB/s, 或4.224Gbps。PCI被设计成支持各种各样基于微处理机的配置，包括单处理机和多处理机的系统。因此，它提供了一组通用的功能。PCI使用同步时序以及集中式仲裁方案。 在多处理机系统中，一个或多个PCI配置可通过桥接器连接到处理机的系统总线上。系统总线只支持处理机/高速缓存单元、主存储器以及PCI桥接器。使用桥接器使得PCI独立于处理机速度，又提供快速接收和传送数据的能力。 2.1 光存储介质：高密度存储器 2.1.1 光盘 光盘技术最终可能使磁盘和磁带存储淘汰。用这种技术，磁存储器所用的读/写头被两束激光代替。一束激光通过在光盘上刻制微小的凹点，对记录表面进行写；而另一束激光用来从光敏感的记录表面读取数据。由于光束容易被偏转到光盘上所需要的位置，所以不需要存取臂。 对用户而言，光盘正成为最有吸引力的选择。它们(光盘)对环境变化不太敏感，并且它们以每兆字节比磁盘低得多的存储器价格提供更多的直接存取存储器。光盘技术仍在出现，并且还需要稳定；然而，目前有三种主要类型的光盘。它们是CD-ROM、WORM盘和磁光盘。 CD-ROM 1980年引入的，非常成功的CD，或紧密盘是设计来提高音乐的录音重放质量的光盘。为了制作一张CD，把音乐的模拟声音转换成等价的数字声音，并且存储在一张4.72英寸的光盘上。在每张光盘上可以用数字格式（用20亿数字位）记录74分钟的音乐。因为它的巨大存储容量，计算机工业的企业家们立刻认

现代大学英语精读3课文电子版

Michael Welzenbach 1. When I was 12 years old, my family moved to England, the fourth major move in my short life. My father’s government job demanded that he go overseas every few years, so I was used to wrenching myself away from friends. 2. We rented an 18th-century farmhouse in Berkshire. Nearby were ancient castles and churches. Loving nature, however, I was most delighted by the endless patchwork of farms and woodland that surrounded our house. In the deep woods that verged against our back fence, a network of paths led almost everywhere, and pheasants rocketed off into the dense laurels ahead as you walked. 3. I spent most of my time roaming the woods and fields alone, playing Robin Hood, daydreaming, collecting bugs and bird-watching. It was heaven for a boy —but a lonely heaven. Keeping to myself was my way of not forming attachments that I would only have to abandon

土木工程类专业英文文献及翻译

PA VEMENT PROBLEMS CAUSED BY COLLAPSIBLE SUBGRADES By Sandra L. Houston,1 Associate Member, ASCE (Reviewed by the Highway Division) ABSTRACT: Problem subgrade materials consisting of collapsible soils are com- mon in arid environments, which have climatic conditions and depositional and weathering processes favorable to their formation. Included herein is a discussion of predictive techniques that use commonly available laboratory equipment and testing methods for obtaining reliable estimates of the volume change for these problem soils. A method for predicting relevant stresses and corresponding collapse strains for typical pavement subgrades is presented. Relatively simple methods of evaluating potential volume change, based on results of familiar laboratory tests, are used. INTRODUCTION When a soil is given free access to water, it may decrease in volume, increase in volume, or do nothing. A soil that increases in volume is called a swelling or expansive soil, and a soil that decreases in volume is called a collapsible soil. The amount of volume change that occurs depends on the soil type and structure, the initial soil density, the imposed stress state, and the degree and extent of wetting. Subgrade materials comprised of soils that change volume upon wetting have caused distress to highways since the be- ginning of the professional practice and have cost many millions of dollars in roadway repairs. The prediction of the volume changes that may occur in the field is the first step in making an economic decision for dealing with these problem subgrade materials. Each project will have different design considerations, economic con- straints, and risk factors that will have to be taken into account. However, with a reliable method for making volume change predictions, the best design relative to the subgrade soils becomes a matter of economic comparison, and a much more rational design approach may be made. For example, typical techniques for dealing with expansive clays include: (1) In situ treatments with substances such as lime, cement, or fly-ash; (2) seepage barriers and/ or drainage systems; or (3) a computing of the serviceability loss and a mod- ification of the design to "accept" the anticipated expansion. In order to make the most economical decision, the amount of volume change (especially non- uniform volume change) must be accurately estimated, and the degree of road roughness evaluated from these data. Similarly, alternative design techniques are available for any roadway problem. The emphasis here will be placed on presenting economical and simple methods for: (1) Determining whether the subgrade materials are collapsible; and (2) estimating the amount of volume change that is likely to occur in the 'Asst. Prof., Ctr. for Advanced Res. in Transp., Arizona State Univ., Tempe, AZ 85287. Note. Discussion open until April 1, 1989. To extend the closing date one month,

计算机专业英语翻译

计算机专业英语翻译 1.1细看处理器与主存储器 我们已经了解到所有计算机有类似的能力且能执行相同的功能,尽管一些可能比其他的快。我们知道电脑系统有输入、输出、仓储、加工的元件,还知道处理器是计算机系统的“智能”部分,并且知道一个简单的计算机系统可以有几个处理器。我们已经讨论了在电脑系统中数据以被称作位的电子状态来表示。我们现在准备阐释计算机系统核心的内部活动——处理器。 电脑的内部操作很有趣,但真的没有什么奥秘的事。这种神秘性存在于那些道听途说和相信科幻作家的人心中。计算机是不会思考的电子设备,它必须插入电源,就像一台烤面包机或一盏灯。 毫不夸张地讲,市场上有几百种不同类型的计算机在销售。每种类型可能都很复杂,但每个处理器,有时被称为中央处理器或者说CPU,只有两个基本部分:控制单元,算术和逻辑单元。主存储器在处理器的内部发挥着重要作用。这三个——主存、控制单元,算术和逻辑单元——一起工作。让我们来看看他们之间的功能和联系。 与磁辅助存储设备,如磁带、磁盘相比,主存没有移动部件。没有机械的运动,数据可以以电子的速度被存取访问,接近光速。今天大多数电脑的主存使用 DRAM(动态随机访问存储器)技术。先进的DRAM芯片大约有1/8邮票那么大,大约可以储存256,000万位或多于25,600,000字符的数据。 主存储器,或者主存,提供给处理器的程序和数据暂时的存储。在可执行程序或数据 本材料版权归八舍109所有，任何人以任何形式使用请自觉支付版税～

可以被处理之前,所有的程序和数据必须被从输入设备(如VDT)或从辅助存储(如磁盘)转移到主存储器。主要的存储空间总是很少;因此,在一个程序被执行后,它占领的储藏空间会被重新分配给另一个等待执行的程序。 图1 - 1说明了所有的输入/输出(I / O)“读”或“用”主要的存储。图中(输入)探讨是在VDT上。消息被查询的形式,是通过一个渠道到主存储器(如同轴电缆)。消息被解释,处理机从辅助存储设备取出所需的程序和数据。程序和数据被“装好”,或移动,从辅助存储器到主存储器。这是一个无损阅读过程。也就是说,程序和数据被从主要存储器(暂时的)和辅助存储器(永久)中读取。数据根据程序指令被操作,报告被从主存储器写入到打印机。 一个程序指令或一块数据保存在的特定的主存单元被称为地址。地址允许程序指令和数据被存储,访问和加工。每一个地址的内容随着不同程序的执行和新的数据的处理是不断变化的。 主存储器的另一个名字是随机存取存储器,或RAM。一种特殊类型的主存储器,称为只读存储器(ROM),不能被程序员改写。ROM的内容被制造商作为“只读”所固化,设计在芯片的逻辑上,。当你打开微机系统,一个ROM中的程序自动启动计算机系统。然后ROM程序初步显示屏幕提示。 ROM的一种变种是可编程的只读存储器(PROM)。RPOM是让用户能装载“只读”的程序和数据的ROM。一旦一个程序被加载到PROM,它简直从不改变。然而,如果你本材料版权归八舍109所有，任何人以任何形式使用请自觉支付版税～ 需要能够修改内容的PROM,有EPROM,可擦写的PROM。在写操作之前,所有的储存单元必须被删除到同样的初始状态。 一个更具有吸引力的形式的主读存储器是电可擦可编程只读存储器(EEPROM)。在任何时候都可以写入,不需擦除原先内容,且只是更新寻址到的字节或多个字节。

建筑外文文献及翻译

外文原文 Study on Human Resource Allocation in Multi-Project Based on the Priority and the Cost of Projects Lin Jingjing , Zhou Guohua SchoolofEconomics and management, Southwest Jiao tong University ,610031 ,China Abstract----This paper put forward the a ffecting factors of project’s priority. which is introduced into a multi-objective optimization model for human resource allocation in multi-project environment . The objectives of the model were the minimum cost loss due to the delay of the time limit of the projects and the minimum delay of the project with the highest priority .Then a Genetic Algorithm to solve the model was introduced. Finally, a numerical example was used to testify the feasibility of the model and the algorithm. Index Terms—Genetic Algorithm, Human Resource Allocation, Multi-project’s project’s priority . 1.INTRODUCTION More and more enterprises are facing the challenge of multi-project management, which has been the focus among researches on project management. In multi-project environment ,the share are competition of resources such as capital , time and human resources often occur .Therefore , it’s critical to schedule projects in order to satisfy the different resource demands and to shorten the projects’ duration time with resources constrained ,as in [1].For many enterprises ,the human resources are the most precious asset .So enterprises should reasonably and effectively allocate each resource , especially the human resource ,in order to shorten the time and cost of projects and to increase the benefits .Some literatures have

计算机专业英语翻译题

Text A https://www.sodocs.net/doc/823866269.html,puter is an electronic equipment which can make arithmetic and logical calculation process information rapidly and automatically. 计算机是一种能够高速、自动地进行算术和逻辑运算及信息处理的电子设备。3.The purpose of inventing and developing computer is to make arithmetic calculations rapidly accurately. 发明和开发计算机的目的是使算术运算快速准确。 4.Production management ,data counting,office automation,traffic dispatching,information retrieval all belong to this field. 生产管理，数据统计，办公自动化，通信调度，信息检索都属于这一领域。 5.Real-time means that the time of computer’s calculating and controlling may match the time of controlled object’s practical running or working. 实时意味着计算机的计算和控制的时间符合受控对象的实际运行或工作的时间。Text B 1.Perhaps the most significant date in the history of computers is the year 1936.it was in this year that the first “computer”was developed。It was created by Konrad Zuse and dubbed the ZI Computer. 也许在计算机历史上最显著日期是今年1936.它是在今年的第一个“电脑”被开发，它由康拉德·楚泽创建，并冠以ZI计算机。 2.While expensive, these machines started the trend for computers within common households. 虽然昂贵，这些机器启动电脑的趋势在普通家庭。 3.Two years later ,the Harvard Mark I computer was developed, furthering the science of computing 两年后，哈佛大学马克一号电脑的开发，促进了科学计算。