电气工程及其自动化专业英语第6章6-1翻译

电气工程及其自动化专业英语第6章6-1翻译
电气工程及其自动化专业英语第6章6-1翻译

Electric Power Systems 电力系统

Section 1 Introduction 第一节介绍

The modern society depends on the electricity supply more heavily than ever before. 现代社会的电力供应依赖于更多地比以往任何时候。It can not be imagined what the world should be if the electricity supply were interrupted all over the world. 它无法想象的世界应该是什么,如果电力供应中断了世界各地。Electric power systems (or electric energy systems), providing electricity to the modern society, have become indispensable components of the industrial world. 电力系统(或电力能源系统),提供电力到现代社会,已成为不可缺少的组成部分产业界的。

The first complete electric power system (comprising a generator, cable, fuse, meter, and loads) was built by Thomas Edison –the historic Pearl Street Station in New Y ork City which began operation in September 1882. 第一个完整的电力系统(包括发电机,电缆,熔断器,计量,并加载)的托马斯爱迪生所建-站纽约市珍珠街的历史始于1882年9月运作。This was a DC system consisting of a steam-engine-driven DC generator supplying power to 59 customers within an area roughly 1.5 km in radius. The load, which consisted entirely of incandescent lamps, was supplied at 110 V through an underground cable system. 这是一个半径直流系统组成的一个蒸汽发动机驱动的直流发电机面积约1.5公里至59供电范围内的客户。负载,其中包括完全的白炽灯,为V提供110通过地下电缆系统。Within a few years similar systems were in operation in most large cities throughout the world. With the development of motors by Frank Sprague in 1884, motor loads were added to such systems. This was the beginning of what would develop into one of the largest industries in the world. In spite of the initial widespread use of DC systems, they were almost completely superseded by AC systems. By 1886, the limitations of DC systems were becoming increasingly apparent. They could deliver power only a short distance from generators.

在一个类似的系统在大多数大城市在世界各地运行数年。随着马达的弗兰克斯普拉格发展在1884年,电机负载被添加到这些系统。这是什么开始发展成为世界上最大的产业之一。在最初的直流系统广泛使用尽管如此,他们几乎完全被空调系统所取代。到1886年,直流系统的局限性也日益明显。他们可以提供功率只有很短的距离从发电机。

To keep transmission power losses ( I 2 R ) and voltage drops to acceptable levels, voltage levels had to be high for long-distance power transmission. Such high voltages were not acceptable for generation and consumption of power; therefore, a convenient means for voltage transformation became a necessity. 为了保持发射功率损失(我2 R)和电压下降到可接受的水平,电压等级,必须长途输电高。如此高的电压不发电和电力消耗可以接受的,因此,电压转换成为一个方便的手段的必要性。

The development of the transformer and AC transmission by L. Gaulard and JD Gibbs of Paris, France, led to AC electric power systems. 在发展的变压器,法国和交流输电由L.巴黎戈拉尔和JD吉布斯导致交流电力系统。

In 1889, the first AC transmission line in North America was put into operation in Oregon between Willamette Falls and Portland. 1889年,第一次在北美交流传输线将在俄勒冈州波特兰之间威拉梅特大瀑布和实施。

It was a single-phase line transmitting power at 4,000 V over a distance of 21 km. With the development of polyphase systems by Nikola Tesla, the AC system became even more attractive. By 1888, Tesla held several patents on AC motors, generators, transformers, and transmission systems. Westinghouse bought the patents to these early inventions, and they formed the basis of the present-day AC systems.这是一个单相线路传输功率为4,000公里,超过21 V系统的距离。随着交流的发展多相系统由尼古拉特斯拉,成为更具吸引力的。通过1888年,特斯拉举行交流多项专利电动机,发电机,变压器和输电系统。西屋公司购买了这些早期的发明专利,并形成了系统的基础,现在的交流。

In the 1890s, there was considerable controversy over whether the electric utility industry should be standardized on DC or AC. By the turn of the century, the AC system had won out over the DC system for the following reasons: 在19世纪90年代,有很大的争议或交流电力行业是否应该统一于直流。到了世纪之交的,在交流系统赢得了原因出在下面的直流系统为:

(1)V oltage levels can be easily transformed in AC systems, thus providing the flexibility for use of different voltages for generation, transmission, and consumption. (1)电压水平可以很容易地改变了空调系统,从而提供了传输的灵活性,发电用不同的电压和消费。

(2)AC generators are much simpler than DC generators. (2)交流发电机简单得多比直流发电机。

(3)AC motors are much simpler and cheaper than DC motors. (三)交流电机和电机便宜简单得多,比直流。

The first three-phase line in North America went into operation in 1893——a 2,300 V, 12 km line in southern California. 前三个阶段的美国北线投产于1893年- 1 2300五,南加州12公里路线研究。In the early period of AC power transmission, frequency was not standardized. 在电力传输初期交流,频率不规范。Many different frequencies were in use: 25, 50, 60, 125, and 133 Hz. 有许多不同频率的使用:25,50,60,125,和133赫兹。This poses a problem for interconnection. Eventually 60 Hz was adopted as standard in North America, although 50 Hz was used in many other countries. 这对互连的问题。最后60赫兹标准获得通过,成为美国在北美,虽然是50赫兹在许多其他国家使用。

The increasing need for transmitting large amounts of power over longer distance created an incentive to use progressively high voltage levels. To avoid the proliferation of an unlimited number of voltages, the industry has standardized voltage levels. In USA, the standards are 115, 138, 161, and 230 kV for the high voltage (HV) class, and 345, 500 and 765 kV for the extra-high voltage (EHV) class. In China, the voltage levels in use are 10, 35, 110 for HV class, and 220, 330 (only in Northwest China) and 500 kV for EHV class . 较长的距离越来越需要大量的电力传输多激励他们逐步使用高压的水平。为了避免电压增殖数量无限,业界标准电压水平。在美国,标准是115,138,161,和230千伏的高电压(高压)类,345,500和765千伏级的特高电压(超高压)。在中国,各级使用电压为10,35,110级高压,220,中国330(仅在西北)和500千伏超高压类。

The first 750 kVtransmission line will be built in the near future in Northwest China. 第一个750 kVtransmission线将建在不久的将来在中国西北地区。

With the development of the AC/DC converting equipment, high voltage DC (HVDC) transmission systems have become more attractive and economical in special situations. 随着交流的发展/直流转换设备,高压直流高压直流(HVDC)传输系统已经成为更具吸引力的经济和情况特殊。The HVDC transmission can be used for transmission of large blocks of power over long distance, and providing an asynchronous link between systems where AC interconnection would be impractical because of system stability consideration or because nominal frequencies of the systems are different. 在高压直流输电可用于输电块以上的大长途电话,并提供不同系统间的异步连接在AC联网系统将是不切实际的,因为稳定考虑,或因标称频率的系统。

The basic requirement to a power system is to provide an uninterrupted energy supply to customers with acceptable voltages and frequency. 基本要求到电源系统是提供一个不间断的能源供应,以客户可接受的电压和频率。Because electricity can not be massively stored under a simple and economic way, the production and consumption of electricity must be done simultaneously. A fault or misoperation in any stages of a power system may possibly result in interruption of electricity supply to the customers. 由于电力无法大量储存在一个简单的方法和经济,电力的生产和消费必须同时进行。系统的故障或误操作的权力在任何阶段可能导致电力供应中断给客户。Therefore, a normal continuous operation of the power system to provide a reliable power supply to the customers is of paramount importance. 因此,一个正常的电力系统连续运行的,提供可靠的电力供应给客户的重要性是至关重要的。

翻译

Power system stability may be broadly defined as the property of a power system that enables it to remain in a state of operating equilibrium under normal operating conditions and to regain an acceptable state of equilibrium after being subjected to a disturbance. 电力系统稳定,可广泛定义为干扰财产的权力系统,可继续经营的状态下正常运行的平衡条件和后向遭受恢复一个可以接受的平衡状态。

Instability in a power system may be manifested in many different ways depending on the system configuration and operating mode. 在电力系统的不稳定可能会表现在经营方式和多种不同的方式取决于系统配置。

Traditionally, the stability problem has been one of maintaining synchronous operation. Since power systems rely on synchronous machines for generation of electrical power, a necessary condition for satisfactory system operation is that all synchronous machines remain in synchronism or, colloquially "in step". This aspect of stability is influenced by the dynamics of generator rotor angles and power-angle relationships, and then referred to " rotor angle stability ". 传统上,稳定性问题一直是一个保持同步运行。由于电力系统的发电电力,一个令人满意的系统运行的必要条件是,依靠同步电机同步电机都留在同步或通俗的“步骤”。这一方面是受稳定的发电机转子的动态角度和功角的关系,然后提到“转子角稳定”。

电气专业英语论文

Page1 Electrical Energy Transmission(电能输送) From reference 1 Growing populations and industrializing countries create huge needs for electrical energy. Unfortunately, electricity is not always used in the same place that it is produced, meaning long-distance transmission lines and distribution systems are necessary. But transmitting electricity over distance and via networks involves energy loss. So, with growing demand comes the need to minimize this loss to achieve two main goals: reduce resource consumption while delivering more power to users. Reducing consumption can be done in at least two ways: deliver electrical energy more efficiently and change consumer habits. Transmission and distribution of electrical energy require cables and power transformers, which create three types of energy loss: the Joule effect, where energy is lost as heat in the conductor (a copper wire, for example); magnetic losses, where energy dissipates into a magnetic field; the dielectric effect, where energy is absorbed in the insulating material. The Joule effect in transmission cables accounts for losses of about 2.5 % while the losses in transformers range between 1 % and 2 % (depending on the type and ratings of the transformer). So, saving just 1 % on the electrical energy produced by a power plant of 1 000 megawatts means transmitting 10 MW more to consumers, which is far from negligible: with the same energy we can supply 1 000 - 2 000 more homes. Changing consumer habits involves awareness-raising programmers, often undertaken by governments or activist groups. Simple things, such as turning off lights in unoccupied rooms, or switching off the television at night (not just putting it into standby mode), or setting tasks such as laundry for non-peak hours are but a few examples among the myriad of possibilities. On the energy production side, building more efficient transmission and

翻译期末作业

浅谈中国菜名的翻译 我国悠久的历史和广袤的国土孕育了中国独特的烹饪艺术和丰富的饮食文化。我们国家也以几千年的饮食文化文明于世。随着我国经济飞速发展,与国外交流日益增多,餐饮业也面临着走向世界的机遇和挑战。中国菜名是汉语语汇中承载中国文化最多的语汇之一, 不仅承载着几千年来的中国饮食文化, 还承载着大量的非饮食文化, 如神话、民俗、历史、文学、宗教信仰等等, 在菜名所传达的表层语义背后有着更为深厚复杂的多元文化元素。同时由于饮食与文化的密切联系,这些都大大增大了翻译的难度。 1.首先我们来看一下一些我们常见的错误翻译 长期以来,菜名的翻译没有统一的标准,加上译者水平有限和地域差异,并不了解菜式的内涵,致使很多菜名的翻译让人感到不知所云。比如口水鸡slobbering chicken、童子鸡chicken without sexual life、夫妻肺片the couple’s lung 等,这翻译让外国人看了都吓跑了,哪里还有食欲吃饭呢?再如东坡肉poet Dongpo’s braised pork,东坡肉是用蒸的方法做出来的,所以这里应该为Poet Dongpo’s steamed pork 而不是用braised;“鱼香肉丝”较常见的有两种译法,另外也有人译为shredded pork with garlic sauce,前者译法为直译,后者加了简单的解释,虽然看似简单易懂,很直观,但是译者没有弄清楚此菜的配料,川菜口味浓重,很多菜肴的配料都是少不了“川菜之魂”郫县豆瓣酱,鱼香肉丝正是用到此配料,是不用所谓的大蒜酱,所以后者翻译存在误的地方;水煮鱼,也是川菜中的代表作,又麻又辣,有译者翻译为tender stewed fish,这个译法不够全面,应该在后面加上in chili sauce;夫妻肺片译为pork lungs in chili sauce,这个译法的译者应该不明白此菜的来历和主料,夫妻肺片根本不是用猪肺做成的,而且和肺一点都不沾边,此菜的主料都是用牛内脏,所以这个译发讲不通。对于以上的翻译错误我们不能只是一笑而过,我们应该感受到菜名翻译的难度,从而思考怎样才能更好的翻译来达到最佳的效果。

自动化专业英语考试翻译

PART 3 Computer Control Technology UNIT 1 A 计算机的结构与功能 这一节介绍计算机的内部体系结构,描述了指令如何存储和译码,并解释了指令执行周期怎样分解成不同的部分。 从最基本的水平来讲,计算机简单执行存储在存储器中的二进制编码指令。这些指令按照二进制编码数据来产生二进制编码结果。对于通用可编程计算机,四个必要部件是存储器、中央处理单元(CPU,或简称处理器),外部处理器总线,输入/输出系统,正如图 3-1A-1所示。 外部处理器总线 存储器CPU输入/输出 图 3-1A-1 计算机的基本元件 存储器储存指令和数据。 CPU读取和解释指令,读每条指令所需的数据,执行指令所需的操作,将结果存回存储器。CPU所需的操作之一是从外部设备读取或写入数据。这利用输入/输出系统来实现。 外部处理器总线是一套能在其他计算机部件之间传送数据、地址和控制信息的电导线。 存储器 计算机的存储器是由一套连续编号的单元所组成。每个存储单元是一个能存二进制信息的寄存器。单元的编号称为地址。初始地址为0。制造商定义处理器的一个字长为单元的整数长。在每个字中,各位表示数据或指令。对于英特尔8086/87和摩托罗拉MC68000微处理器来说,一个字是16位长,但每个存储单元仅为8位,因此两个8位单元来存取获得一个数据字长。

为了使用存储器中的内容,处理器必须取来右边的内容。为了完成这一次读取,处理器把所需单元的二进制编码地址放到外部处理器地址总线的地址线上,然后,存储器允许处理器读取所寻址的存储单元的内容。读取存储单元的内容的这一过程并不改变该单元的内容。 存储器中的指令存储器中的指令由CPU取来。除非发生程序转移,它们按在存储器中出现的顺序来执行。用二进制形式所写的指令叫做机器语言指令。一种得到(指令)有效形式的方法是将(这些)位分成段,如图3-1A-2所示。每一段都包含一个不同类型信息的代码。 在简单的计算机中,每条指令可分为四段,每段有四位。每条指令包括操作代码(或操作码,每条指令有唯一的操作码)、操作数地址、立即数、转换地址。 在一个实际的指令集中,有很多指令。也有大量的存储单元来存储指令和数据。为了增加存储单元的数目,如果我们使用同样的方法,地址段的指令一定长于16位。除了增加指令长度外,还有很多增加微处理器寻址范围的方法:可变指令段、多字指令、多寻址模式,可变指令长度。我们不将详细讨论它们。 存储数据数据是存储器中代表代码的信息。为了有效利用存储空间和处理时间,大多数计算机提供了不同长度和表示方法的处理数据能力。能被处理器识别的各种不同表示称作数据类型。常用的数据类型有:位、二进制码、十进制数字(4位字节,BCD)、字节(8位)、字(2个字节)、双字(4个字节)。 有一些处理器提供了可处理其他数据类型。例如单精度浮点数据类(32位)和双精度浮点数据(64位)等的指令。还有另一类的数据–––特征数据。通常也表示为8位。在标准键盘上,每个计算机终端键和键的组合(例如shift和control功能键)有定为美国信息交换标准码的7位码。 存储器类型在数字控制系统的应用中,我们也关注不同存储技术的特征。对主存储器来说,我们需用它临时存储信息,并逐次地从不同单元写入或获得信息。这种类型的存储器称作随机访问存储器(RAM)。在某些情况下,我们不想让存储器中的信息丢失。因此我们愿使用特殊技术写入存储器。如果写入只在物理改变连接时才能实现,那么这种存储器称为只读存储器(ROM)。如果相互连接的模式可由程序设定,那存储器叫做可编程只读存储器(PROM)。如果需要实现改写的情况,我们有可擦的可编程只读存储器(EPROM)。电可擦除的PROM缩写为EEPROM。

土木专业英语翻译作业

桂林理工大学土木与建筑工程学院 土木工程专业英语外文翻译,中文翻译 姓名:马凤志 专业:土木应用 班级:10级9班 学号:3100510939

原文

中文翻译 The Influence of Concrete Compaction on the Strength of Concrete Filled Steel Tubes 压实混凝土对混凝土强度的影响 Lin-Hai Han School of Civil Engineering, Harbin University of Civil Engineering and Architecture, Haihe Road 202, PO Box 689, Harbin 150090, P.R. China 韩林海,哈尔滨建筑大学,土木与建筑工程学院,海河路202号,邮政信箱,689,哈尔滨,150090 中国 ABSTRACT: Tests on twenty-one concrete filled steel tubes to investigate the influence of compaction methods on the strength of concrete filled steel tubular members are reported. 摘要:测试二十一钢管混凝土试验,研究了钢管对混凝土构件强度压实方法的影响报告。 Two parameters were investigated, including slenderness ratio and load eccentricity. 对两个参数进行研究,包括长细比和荷载偏心。 It was found that better compaction of concrete resulted in higher values of the ultimate strength of concrete filled steel

电气毕业论文英语文献原文 翻译

外文翻译院(系) 专业班级 姓名 学号 指导教师 年月日

Programmable designed for electro-pneumatic systems controller John F.Wakerly This project deals with the study of electro-pneumatic systems and the programmable controller that provides an effective and easy way to control the sequence of the pneumatic actuators movement and the states of pneumatic system. The project of a specific controller for pneumatic applications join the study of automation design and the control processing of pneumatic systems with the electronic design based on microcontrollers to implement the resources of the controller. 1. Introduction The automation systems that use electro-pneumatic technology are formed mainly by three kinds of elements: actuators or motors, sensors or buttons and control elements like valves. Nowadays, most of the control elements used to execute the logic of the system were substituted by the Programmable Logic Controller (PLC). Sensors and switches are plugged as inputs and the direct control valves for the actuators are plugged as outputs. An internal program executes all the logic necessary to the sequence of the movements, simulates other components like counter, timer and control the status of the system. With the use of the PLC, the project wins agility, because it is possible to create and simulate the system as many times as needed. Therefore, time can be saved, risk of mistakes reduced and complexity can be increased using the same elements. A conventional PLC, that is possible to find on the market from many companies, offers many resources to control not only pneumatic systems, but all kinds of system that uses electrical components. The PLC can be very versatile and robust to be applied in many kinds of application in the industry or even security system and automation of buildings.

自动化专业英语_考试版的文章翻译

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专业英语大作业

专业英语大作业 一:英译汉 翻译范围TCP/IP Illustrated, V olume 1: The Protocols 5.1~5.5 15.1~15.2 第5章RARP:逆地址解析协议 5.1简介 5.2 RARP报文格式 5.3 RARP示例 5.4 RARP服务的设计 5.5小结 练习 5.1简介 一个拥有本地磁盘的系统通常是从磁盘文件读取配置文件中获取其IP地址。但一个没有磁盘的系统,如X终端或无盘工作站,需要一些其它方式去获得其IP地址。 每个系统在网络上都有一个唯一的硬件地址,由网络接口的制造商分配。 RARP的原则是无盘系统从接口卡上读取其独特的硬件地址,并发送RARP请求(网络上的广播帧)要求别人对无盘系统的IP地址(使用RARP回应)进行应答。 虽然这个概念很简单,执行往往比ARP更难,在本章后面会描述其原因。 RARP的正式规范是RFC 903。 5.2 RARP报文格式 RARP报文的格式几乎与ARP报文是相同的(图4.3)。唯一的区别是,RARP 的请求或应答帧类型为0×8035,并且在操作层RARP请求值为3、RARP应答值为4。 图4-3 ARP在网络上请求与应答报文的格式 与ARP一样,RARP服务器请求是广播和RARP应答通常是单播。 5.3 RARP示例 在我们的网络,我们可以强制sun主机从网络引导,而不是它的本地磁盘。 如果我们在主机bsdi上运行RARP服务器和tcpdump,我们得到如图5.1所示的输出。我们使用-e参数去标记tcpdump的打印硬件地址:

图5.1 RARP请求和应答。 该RARP请求是广播(1号线)的,第2行的RARP应答是单播的。第2行的输出,“at sun”,意味着RARP应答包含了主机sun(140.252.13.33)的IP地址。 在第3行,我们看到,一旦sun接收其IP地址,它会发出一个TFTP读请求(RRQ)的文件8CFCOD21.SUN4C。(TFTP是简单文件传输协议,我们在第15章进行详细描述)。在文件名中的8个十六进制数字是sun主机的IP地址140.252.13.33的十六进制表示形式。这是在RARP应答中返回的IP地址。该文件名的其余部分,后缀SUN4C表示系统正在引导的类型。 Tcpdump表示第3行是一个长度为65的IP数据报,而不是一个UDP数据报(实际上它确实是),因为我们运行tcpdump命令使用-e参数,看硬件级别的地址。另一点,在图5.1要注意的是在第2行的以太网帧的长度似乎比最小较短(我们所说的是在4.5节60字节)。原因是我们的系统,该系统上运行的tcpdump 发送该以太网帧(BSDI)。该应用程序rarpd,写42字节到BSD分组过滤器装置(14字节的以太网报头和28字节的RARP应答),这是什么的tcpdump收到的副本。但以太网设备驱动程序垫这个短帧的最小尺寸为传输(60 )。如果我们在另一个系统上已经运行的tcpdump ,长度会是60。 我们可以看到在这个例子,当这种无盘系统接收在RARP应答它的IP地址,它会发出一个TFTP请求来读取一个引导映像。在这一点上,我们不会进入其他详细介绍无盘系统是如何引导自己。(第16章介绍了使用RARP ,BOOTP和TFTP无盘X终端的引导顺序。) 图5.2表示出了如果有在网络上没有RARP服务器所得到的数据包。每个数据包的目的地址为以太网的广播地址。以太网地址跟随的是目标硬件地址,并按照发送端的硬件地址发送。

上海海洋大学专业英语期末翻译

Analog computers are analog devices. That is, they have continuous states rather than discrete numbered states. An analog computer can represent fractional or irrational values exactly, with no round-off. Analog computers are almost never used outside of experimental settings. 模拟计算机是模拟设备。也就是说,他们是连续状态而不是离散的有限状态。一个模拟计算机可以精确代表小数或无理数,没有舍入。模拟计算机几乎从不被使用在实验设置以外。 A processor typically contains an arithmetic/logic unit (ALU), control unit( including processor flags, flag register, or status register), internal buses, and sometimes special function units( the most common special function unit being a floating point unit for floating point arithmetic). 一个处理器通常包含一个算术/逻辑单元(运算器),控制单元(包括处理器标志,标志寄存器,或状态寄存器),内部总线,有时特殊功能单元(最常见的特殊功能单元作为一个浮点单元用于浮点运算)。 CISC stands for Complex Instruction Set Computer. Mainframe computers and minicomputers were CISC processors, with manufacturers competing to offer the most useful instruction sets. Many of the first two generations of microprocessors were also CISC. CISC代表复杂指令集计算机。大型计算机和小型计算机是CISC处理器,与制造商竞争提供最有用的指令集。微处理器的前两代中许多也是CISC。 Lesson 2 Supercomputer is a broad term for one of the fastest computers currently available. Supercomputers are very expensive and are employed for specialized applications that require immense mounts of mathematical calculations (number crunching). 超级计算机是一个广泛的术语,因为它是目前可用的最快的计算机之一。超级计算机是非常昂贵的,并且它被用于需要大量的数学计算(数字运算)的专门应用。 It is a midsize computer. In the past decade, the distinction between large minicomputers and small mainframes has blurred, however, as has the distinction between small minicomputers and workstation. But in general, a minicomputer is a multiprocessing system capable of supporting up to 200 users simultaneously. 它是一个中型计算机。在过去的十年中,大的小型机和小的大型机之间的区别已经模糊,然而,有小的小型机和工作站之间的区别。但在一般情况下,一个小型机是一个能够同时支持多达200个用户的多处理系统。 Workstations generally come with a large, high-resolution graphics screen, a large amount of RAM, built-in network support, and a graphical user interface. Most workstations also have a mass storage device such as disk drive, but a special type of workstation, called a diskless workstation, comes without a disk drive. 工作站一般都配有一个大的,高分辨率的图形屏幕,大量的内存,内置网络支持以及一个图形用户界面。大多数工作站也有一个大容量存储设备如磁盘驱动器,但是一种特殊类型的工作站,被称为无盘工作站,是不带磁盘驱动器的。

电子商务专业英语作业翻译

E-commerce (electronic commerce or EC) is the buying and selling of goods and services on the Internet, especially the World Wide Web. In practice, this term and a newer term, e-business, are often used interchangably. For online retail selling, the term e-tailing is sometimes used. 电子商务(电子商务或电子商务)是购买和出售的商品和服务在互联网,特别是万维网上的。在实践中,这项和一个新的术语,电子商务,往往交替使用。网上零售,电子零售的术语有时用。 E-tailing or The Virtual Storefront and the Virtual Mall 网上或虚拟商店和虚拟商店 As a place for direct retail shopping, with its 24-hour availability, a global reach, the ability to interact and provide custom information and ordering, and multimedia prospects, the Web is rapidly becoming a multibillion dollar source of revenue for the world's businesses. A number of businesses already report considerable success. As early as the middle of 1997, Dell Computers reported orders of a million dollars a day. By early 1999, projected e-commerce revenues for business were in the billions of dollars and the stocks of companies deemed most adept at e-commerce were skyrocketing. Although many so-called dotcom retailers disappeared in the economic shakeout of 2000, Web retailing at sites such as https://www.360docs.net/doc/d015398418.html,, https://www.360docs.net/doc/d015398418.html,, and https://www.360docs.net/doc/d015398418.html, continues to grow. 作为一个直接的零售购物,其24小时供应,全球性的,互动的能力,并提供自定义信息和订购,和多媒体,网络正在迅速成为一个数十亿美元的收入来源,为全球的企业。一些企业已报告了相当大的成功。早在1997年年中,戴尔电脑报告的订单一百万美元一天。1999年初,预计的电子商务业务收入都在数十亿美元的股票和公司认为最善于电子商务暴涨。虽然许多所谓的互联网零售商消失在经济衰退2000,网上零售网站如https://www.360docs.net/doc/d015398418.html,,https://www.360docs.net/doc/d015398418.html,,和https://www.360docs.net/doc/d015398418.html,继续增长 Market Research 市场研究 In early 1999, it was widely recognized that because of the interactive nature of the Internet, companies could gather data about prospects and customers in unprecedented amounts -through site registration, questionnaires, and as part of taking orders. The issue of whether data was being collected with the knowledge and permission of market subjects had been raised. (Microsoft referred to its policy of data collection as "profiling" and a proposed standard has been developed that allows Internet users to decide who can have what personal information.) Electronic Data Interchange (EDI)

电气自动化专业毕业论文英文翻译

电厂蒸汽动力的基础和使用 1.1 为何需要了解蒸汽 对于目前为止最大的发电工业部门来说, 蒸汽动力是最为基础性的。 若没有蒸汽动力, 社会的样子将会变得和现在大为不同。我们将不得已的去依靠水力发电厂、风车、电池、太阳能蓄电池和燃料电池,这些方法只能为我们平日用电提供很小的一部分。 蒸汽是很重要的,产生和使用蒸汽的安全与效率取决于怎样控制和应用仪表,在术语中通常被简写成C&I(控制和仪表 。此书旨在在发电厂的工程规程和电子学、仪器仪表以 及控制工程之间架设一座桥梁。 作为开篇,我将在本章大体描述由水到蒸汽的形态变化,然后将叙述蒸汽产生和使用的基本原则的概述。这看似简单的课题实际上却极为复杂。这里, 我们有必要做一个概述:这本书不是内容详尽的论文,有的时候甚至会掩盖一些细节, 而这些细节将会使热力学家 和燃烧物理学家都为之一震。但我们应该了解,这本书的目的是为了使控制仪表工程师充 分理解这一课题,从而可以安全的处理实用控制系统设计、运作、维护等方面的问题。1.2沸腾:水到蒸汽的状态变化 当水被加热时,其温度变化能通过某种途径被察觉(例如用温度计 。通过这种方式 得到的热量因为在某时水开始沸腾时其效果可被察觉,因而被称为感热。 然而,我们还需要更深的了解。“沸腾”究竟是什么含义?在深入了解之前,我们必须考虑到物质的三种状态:固态,液态,气态。 (当气体中的原子被电离时所产生的等离子气体经常被认为是物质的第四种状态, 但在实际应用中, 只需考虑以上三种状态固态,

物质由分子通过分子间的吸引力紧紧地靠在一起。当物质吸收热量,分子的能量升级并且 使得分子之间的间隙增大。当越来越多的能量被吸收,这种效果就会加剧,粒子之间相互脱离。这种由固态到液态的状态变化通常被称之为熔化。 当液体吸收了更多的热量时,一些分子获得了足够多的能量而从表面脱离,这个过程 被称为蒸发(凭此洒在地面的水会逐渐的消失在蒸发的过程中,一些分子是在相当低的 温度下脱离的,然而随着温度的上升,分子更加迅速的脱离,并且在某一温度上液体内部 变得非常剧烈,大量的气泡向液体表面升起。在这时我们称液体开始沸腾。这个过程是变为蒸汽的过程,也就是液体处于汽化状态。 让我们试想大量的水装在一个敞开的容器内。液体表面的空气对液体施加了一定的压 力,随着液体温度的上升,便会有足够的能量使得表面的分子挣脱出去,水这时开始改变 自身的状态,变成蒸汽。在此条件下获得更多的热量将不会引起温度上的明显变化。所增 加的能量只是被用来改变液体的状态。它的效用不能用温度计测量出来,但是它仍然发生 着。正因为如此,它被称为是潜在的,而不是可认知的热量。使这一现象发生的温度被称为是沸点。在常温常压下,水的沸点为100摄氏度。 如果液体表面的压力上升, 需要更多的能量才可以使得水变为蒸汽的状态。 换句话说, 必须使得温度更高才可以使它沸腾。总而言之,如果大气压力比正常值升高百分之十,水必须被加热到一百零二度才可以使之沸腾。

专业英语翻译作业译文

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二0一五年六月 一、英译中(英文科技资料翻译) 原文: An operating system is the software which acts as an interface between a user of a computer and the computer hardware.The purpose of an operating system is to provide an environment in which a user may execute program. The primary goal of an operating system is thus to make the computer system convenient to use. A secondary goal is to use the computer hardware in an efficient way. We can view an operating system as a resource allocator. A computer system has many resources which may be required to solve a problem: CPU time, memory space, , input/output(I/O) devices, and so on.The operating system acts as the manager of these resources and allocates them to specific programs and users as necessary for their tasks. Since there may be many, possibly conflicting, requests for resources, the o/s must decide which requests are allocated resources to operate the computer system fairly and efficiently. Multimedia means, from the user ' perspective, that computer information can be represented through audio and/or video, in addition to text, image, graphics and animation . The integration of these media into the computer provides additional possibilities for the use of computational power currently available (e.g., for interactive presentation of huge amounts of information ). Furthermore, these data can be transmitted though computer and telecommunication networks, which implies applications in the areas of information distribution and cooperative work.Multimedia provides the possibility for a spectrum of new applications, many of which are in place today. A multimedia system distinguishes itself from other systems through several properties. We elaborate on the most important properties such as combination of the media, media-independence, computer control and integration.Not every arbitrary combination of media justifies the usage of the term multimedia. A simple text processing program with incorporated images is often called a multimedia application because two media are processed through one program.But one should talk about multimedia only when both continuous and discrete media are utilized.A text processing program with incorporated images is therefore not a multimedia application. An important aspect of different media is their level of independence from each other. In general, there is a request for independence of different media, but multimedia may require several levels of independence. On the one hand, a computer-controlled video recorder stores audio and video information, but there is an inherently tight connection between the two types of media. Both media are coupled together through the common storage medium of the tape. On the other hand, for the purpose of presentations, the combination of DAT recorder (Digital Audio Tape) signals and computer-available text satisfies the request for media-independence. Early computers were(physically) very large machines run from a console.The programmer would

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