专业英语 7

1.what's a shopping cart?

A shopping cart is a order-processing technology that allows customers to accumulate items they wish to buy as they continue to shop.

2.What's the difference between business model and revenue model?

A business model is a set of processes that combine to achieve a company's goal,which is to yield a profit.

A revenue model ,which is a specific collection of business processes used to identify customers,market to those customers,and generate sales to those customers.

3.What are Transaction costs?

Transaction costs are the total costs that a buyer and seller incur as they gather information and negotiate a purchase-sale transaction.

4.list Five parties may be involved in the e-payment method:

(1)Customer/payer/buyer. 客户/付款人/买主

The party making the e-payment in exchange for goods or services.

(2)Merchant/payee/seller. 商人/收款人/销售者

The party receiving the e-payment in exchange for goods and services.

(3)Issuer. 发行者

The banks or nonbanking institutions that issue the e-payment instrument used to make the purchase.

(4)Regulator. 管理者

Usually a government agency whose regulations control the e-payment process.

(5)ACH (Automated Clearing House). 自动化交易所

An electronic network that transfers money between bank accounts.

5.What are credit cards?

A credit card provides the holder with credit to make purchases up to a limit fixed by the card issuer.

6.What are virtual credit cards?

Virtual credit card is an e-payment system in which a credit card issuer issues a special number that can be used in place of regular credit card numbers to make online purchases.

7.Describe the four main catagories of EC intermediaries?

Brokers match buyers and sellers for a fee.

Auctioneers set up a mechanism to determine prices.

Dealers take ownership of goods provided by suppliers and resell them to buyers.

Exchanges are double-sided markets, similar to existing markets for financial instruments and some commodities.

8.what dose Authentication/Authorization mean?

9.what’s the difference between Authentication and Authorization?(8和9答案相同) Authentication

The process by which one entity verifies that another entity is who they claim to be is called authentication.

Authorization

Authorization ensures that a person or program has the right to access certain resources.

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SAND CASTING Most metal castings are made by pouring molten metal into a prepared cavity and allowing it to solidify. The process dates from antiquity. The largest bronze statue in existence today is the great Sun Buddha in Nara, Japan. Cast in the eighth century, it weighs 551 tons (500 metric tons) and is more than 71 ft (21m) high. Artisans of the Shang Dynasty in China (1766 - 1222B.C.) created art works of bronze with delicate filigree as sophisticated as anything that is designed and produced today. There are many casting processes available today, and selecting the best one to produce a particular part depends on several basic factors, such as cost, size, production rate, finish ,tolerance, section thickness, physical-mechanical properties, intricacy of design, machinability, and weldability. Sand casting, the oldest and still the most widely used casting process, will be presented in more detail than the other processes since many of the concepts carry over into those processes as well. Green Sand Green sand generally consists of silica sand and additives coated by rubbing the sand grains together with clay uniformly wetted with water.More stable and refractory sands have been developed, such as fused silica, zircon, and mullite, which replace lower-cost silica sand and have only 2% linear expansion at ferrous metal temperatures. Also, relatively unstable water and clay bonds are being replaced with synthetic resins, which are much more stable at elevated temperatures. Green sand molding is used to produce a wide variety of castings in sizes of less than a pound to as large as several tons. This versatile process is applicable to both ferrous and nonferrous materials. Green sand can be used to produce intricate molds since it provides for rapid collapsibility; that is, the mold is much less resistant to the contraction of the casting as it solidifiesthan are other molding processes. This results in less stress and strain in the casting. The sand is rammed or compacted around the pattern by a variety of methods, including hand or pneumatic-tool ramming, jolting (abrupt mechanical shaking),

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专业英语

直升机helicopter 机体 fuselage,body 座舱 main cabin 旋翼桨叶rotor 旋翼桨毂rotor head 旋翼铰rotor hinge 自动倾斜器swashplate 尾桨桨叶tail rotor 尾桨桨毂tail rotor head 主减速器 main gearbox 中间减速器middle gearbox 尾部减速器rail gearbox 功率输出轴power transmissionshaft 尾部传动轴tail transmissionshaft 水平尾翼，平尾 horizontal tail 垂直尾翼，垂尾 vertical tail 水平安定面 stabilizer 垂直安定面 fin 起落架 undercarriage,landing gear 定轴式涡轮轴发动机fixed shaftturbine yur-boshaft engine 辅助动力装置auxiliary powerunit 燃油调节器 fuel regulator 驾驶杆control stick ,cyclic 脚蹬 pedal,anti-torque pedal 总距杆collective 旋翼转速 rotor speed 尾翼 tail 重心 center of gravity 外挂物 external stores 高度表 altimeter 空速表 air-speed meter,air-speed indic-tor 升降速度表 vertical-speed indicator,rate-of-climb meter

功率 power 转速 speed of revolution 进气道 air intake,air inlet 表速 indicated airspeed 真速 true airspeed 高度 height altitude 升力 lift 拉力 thrust 阻力 drag 诱导阻力 induced drag 摩擦阻力 skin-friction drag 压差阻力 pressure drag 升力系数 lift coefficient 阻力系数 drag coefficient 迎角 angle of attack,angle of incidence 失速 stall 升阻比 lift-drag ratio 地面效应 ground effect 标准大气压 standard atmosphere 侧滑角 angle of sideslip 俯仰角 angle of pitch,inclination angle,el-evation 偏航角 angle of yaw,azimuth angle 滚转角 angle of roll,angle of bank,bank angle 航迹倾斜角 flight path angle,flight-pathinclinationangle,flight-path climb an-gle,angle of velocity pitch 轨迹偏转角course angle,flight-path track angle,angleof velocity yaw 速度滚转角angle of roll,flight-path bankangle,angle ofvelocity roll 俯仰角速度rate of pitch 偏航角速度rate of yaw 滚转角速度rate of roll

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专业英语

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专业英语-整理版

Chapter 1 Introduction: Why Project Management? True/False 1) Projects have a process orientation. F 2) Client interest in a project is highest during the termination and conceptual phases. T Multiple Choice 1). A project typically has: A) A defined start and end date. B) A defined start date but no defined end date. C) No defined start but a defined end date. D) No defined start or end date. 2) Which of the following statements about project success criteria is best? A) Project cost is an external performance measure. B) Completion time is an internal performance measure. C) Client acceptance is an internal performance measure. D) Client acceptance is often referred to as conducting a quality check. Short Answer 1) What changes in the business environment have necessitated a greater use of project management skills?

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Key to Unit 7 Page 126 Text Comprehension I. D II. 1. F 2. F 3.T 4.T 5. F IV 1.I tried to comfort her by saying that we would manage to tide it over. 2.After experiencing such an incident, the girl’s visit to London would seem much less exciting in comparison. 3.The young woman, who was as confident as that businessman, must have noticed my fear. 4.The young businessman was sorry that he had not got a chance to buy his two little girls a present. 5.I am very grateful to my fellow passengers. Page 127 Vocabulary I. 1.having the seat belt fastened on 2.catch another flight to continue the journey 3.he had completed his task (announcement) 4.controlled my feelings and began behaving calmly again https://www.wendangku.net/doc/ef7971334.html,nd successfully and safely 6.am very grateful to, do something nice in return II. 1.witnessed 2.figured

电子信息类专业英语翻译

1.This electron beam sweeps across each line at a uniform rate，then flies back to scan another line directly below the previous one and so on，until the horizontal lines into which it is desired to break or split the picture have been scanned in the desired sequence． 电子束以均匀的速率扫描每一行，然后飞速返回去扫描下一行，直到把被扫描的图像按所希望的顺序分割成行。 2.The technical possibilities could well exist，therefore，of nation-wide integrated transmission network of high capacity，controlled by computers，interconnected globally by satellite and submarine cable，providing speedy and reliable communications throughout the word 因此，在技术上完全可能实现全国性的集成发送网络。这种网络容量大，由计算机控制，并能通过卫星和海底电缆实现全球互联，提供世界范围的高速、可靠的通信。 3.Transit time is the primary factor which limits the ability of a transistor to operate at high frequency． 渡越时间是限制晶体管高频工作能力的主要因素 4.The intensity of sound is inversely proportional to the square of the distance measured from the source of the sound. 声强与到声源的距离的平方成反比。 5.The attenuation of the filter is nearly constant to within 0.5 dB over the entire frequency band． 该滤波器的衰减近于恒定, 整个频带内的变化在0.5 dB以内。 6.At present, the state of most semiconductor device technology is such that the device design and process technology must be supplemented by screening and inspection procedures, if ultimate device reliability is to be obtained and controlled． 目前, 大多数半导体器件的技术尚未十分完善, 以至若要获得并控制器件最终的可靠性, 就必须辅以筛选和检验, 以弥补设计和工艺技术之不足 7.Bandwidth of transistor amplifiers vary from about 250 MHz in the L band to 1000 MHz in the X band． 晶体管放大器的带宽在L波段约为250 MHz, 在X波段为1000 MHz。 8.The output of the differential amplifier is fed to the circuit’s output stage via an offset-compensation network, which causes the op-amp’s output to center at zero volts. The output stage takes the form of a complementary emitter follower, and provides a low-impedance output. 差动放大级的输出通过一个失调补偿网络与输出级相连, 目的是使运放的输出以0 V为中心。输出级采用互补的射极跟随器的形式以使输出阻抗很低 9.Because of the very high open-loop voltage gain of the op-amp, the output is driven into positive saturation (close to +V) when the sample voltage goes slightly above the reference voltage, and driven into negative saturation (close to-V) when the sample voltage goes slightly below the reference voltage. 由于运放的开环电压增益很高, 当取样电压略高于参考电压时, 输出趋向于正向饱和状态(接近+V)。当取样电压低于参考电压时, 输出趋向于负向饱和状态(接近-V)。 10.If the signal source were direct connected instead of capacitor coupled, there would be a low resistance path from the base to the negative supply line, and this would affect the circuit bias conditions. 如果信号源和电路不是用电容耦合而是直接相连，从基极到负电源线就会一个低阻通路，并且这将影响到电路偏置状态 11.The differential amplifier has a high-impedance (constant-current)“tail”to give it a high input impedance and a high degree of common-mode signal rejection. It also has a high-impedance collector (or drain) load, to give it a large amount of signal-voltage gain (typically about 100 dB). 差动放大极有一个高阻抗的“尾巴”（恒流源）以提供高输入阻抗和对共模信号的深度抑制，同时，它还具有一个高阻抗和集电极或漏极负载以提供高的信号电压增益（典型的数据是100dB). 12.On the other hand, a DC negative-logic system, as in Figure 3.6(b), is one which designates the more negative voltage state of the bit as the 1 level and the more positive as the 0 level. 另一方面, 如图3.6(b)所示, 把比特的较低的电压状态记为1电平, 较高的电压状态记为0电平, 这样的系统称为直流负逻辑系统。 13.For example, to represent the 10 numerals (0, 1, 2, …, 9) and the 26 letters of the English alphabet would require 36 different combinations of 1’s and 0’s. Since 25<36<26, then a minimum of 6 bits per bite are required in order to accommodate all the alphanumeric characters. 例如，要表示0～9十个数字和英文字母表中的26个字母，就需要0和1的36种不同的组合。因为25<36>26,