机械工程英语——Lesson 27 CAD/CAM

CAD  Acronym for computer-aided design. A CAD system is a combination of hardware and software that enables engineers and architects to design everything from furniture to airplanes. In addition to the software, CAD systems require a high-quality graphics monitor; a mouse, light pen, or digitizing tablet for drawing; and a special printer or plotter for printing design specifications.

CAD systems allow an engineer to view a design from any angle with the push of a button and to zoom in or out for close-ups and long-distance views. In addition, the computer keeps track of design dependencies so that when the engineer changes one value, all other values that depend on it are automatically changed accordingly.

Until the mid 1980s, all CAD systems were specially constructed computers. Now, you can buy CAD software that runs on general-purpose workstations and personal computers.

CAM

(1) Short for channel access method, a protocol for how data is transmitted in the bottom two layers of the OSI model. CAMs describe how networking systems put data on the network media, how low-level errors are dealt with, and how the network polices itself. Polling, contention and token passing are three examples of CAMs.

(2) Acronym for computer-aided manufacturing, a type of computer application that helps automating a factory. For example, the following are types of CAM systems

·real-time control

·robotics

·materials requirements

All these systems are concerned with automatically directing the manufacture and inventory of parts.

(3) Slang term to describe a bootleg copy of a movie that was recorded in the movie theater with a digital video camera. It''s usually poor quality and the sound in a CAM is recorded by the cameras microphone, meaning it will capture theater sounds and laughter and such from the attending movie-goers.

Vocabulary

1.acronym n.只取首字母的缩写

2.combination n. 结合，并合

3.architect n. 建筑师

4.light pen n. 光笔

5.tablet n. 写字板

6.bootleg n. 私卖酒

7.digitize v. 将数字化

8.specification n. 设计说明书

9.keeps track of 跟踪，记录

10.dependencies n. 从属

11.accordingly adv. 因此，从而

12.workstation n. 工作站

13.protocol n. 协议

14.police v. 管辖，维持秩序

15.contention n. 论点

16.inventory n. 详细目录

17.Slang n. 俚语

18.capture v. 捕捉

19.goer n. 行人