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计算机科学引论课后题原文

23页

1. A common term that describes the combination of traditional computer and communication

technologies is

a.management of information systems

b. information technology

c. information superhighway

d. computer competency

2. Procedures are typically documented in manuals written by

a. end users c. Microsoft

b. computer specialists d. service providers

3. Which of the following is an example of connectivity?

a. Internet

b. floppy disk

c. power cord

d. dala

4. Windows XP, Windows Vista, and Macintosh OS X are all examples of

a. application software

b. operating systems

c. browsers

d. shareware

5. because of their size and cost, these computers are relatively rare.

a. minicomputers

b. maintrame computers

c. microcomputers

d. supercomputers

6. The system component that controls and manipulates data in order to produce

Information is called the a. monitor

b. mouse

c. keyboard

d. microprocessor

7.A systrm component that translates data and programs that humans can understand

Into a form that the computer can process is called a(n)

a. input device

b. pointer

c. output device

d. display

8. A CD is an example of a(n)

a. output device

b. floppy disk

c. optical disc

d. hard disk

9.If you want to communicate a message or persuade other people, you would typically

a. worksheet

b. document

c. database

d. presentation

10. Many experts are predicting that this revolution iss expected to dramatically affect the

Way we communicate and use computer technology.

a. FTP

b. World Wide Web

c. Telnet

d. wireless

24页

a. microcomputers

b. optical discs

c. output device

d. primary storage

e. procedures

f. program

g. secondary, storage

h. supercomputers

i. system software

j. the Internet

1.Guidelines people follow when using software.__ I

2.Consists of the step-by-step instructions that tell the

computer how to do its work.

3. 3. Software that enables the application software to interact with the computer hardware.

4. The most powerful type of computer.

5. The least powerful and most widely used type of computer.

6. Translates data and programs that humans can understand into a form that the

computer can process.

7. Holds data and programs even after electrical power to the system has been turned off.

8. Uses laser technology. __

9. Holds data and program instructions for processing data

10. The largest network in the world.

55页

1.The Internet was launched m 1969 when the United States funded a project that developed national computer network called

R. AARPNET b. CERNET c. CERN d. ARPANET

2._____ is the most popular" lnternet activity.

a, communication b. shopping c. searching d. entertainment

3.A(n)____program provides access to Web resources.

a. Web

b. ISP c, browser d. URL

4. Rules for exchanging data between computers are called

a. programs

b. procedures

c. protocols

d. hyperlinks

5. The of the domain name following the dot (.) is the top domain,

a. level

b. link

c. locator

d. language

6. ____to add interest and activity to a Web site by presenting animation

Displaying graphics , providing interactive games, and more.

a. Applets

b. Bots

c. Plug-ins

d. Spiders

7. unwanted e-mails are called

a. spam

b. junk

c. flame

d. lurk

8.Programs that submit your search request to several search engines

a. metasearch engines

b. search engines

c. spiders

d. hits

9. ______ cash is the Internet's equivalent to traditional cash

a. Universal

b. Web

c. Premium

d. Digital

10. These programs allow parents as well as organizations to block OUl selected sites and

a. plug-ins

b. filters

c. FTP

d. WAIS

56页

a. carders b digital cash c. e-commerce d. header e. hits r. metasearch engine

g. plug-in h. reuniting i. URLs j. Web auction

1. Addresses of Web resources. _

2. Part of an e-mail message that includes the subject address, and attachments.

3. Program that starts and operates as part of a browser. __

4. The list of sites that contain the keyword search.

5. Program that automatically submits a search request to several search engines

simultaneously.

6. Buying and selling goods over the Internet.

7. Type of social networking site that reconnects people who have lost touch with one another.

8. Similar to a traditional auction, but buyers and sellers typically interact only on the Web.

9. Criminals that specialize in stealing, trading, and using stolen credit cards over the Internet.

10. Internet equivalent to traditional cash.

87页

1.This type of software works with end users, application software, and computer hardware to

handle the majority of technical details.

a. communication software

b. application software

c. Web software

d. system software

2. ____are narrowly focused on specific disciplines and occupations.

a. Basic applications

b. Utility programs

c. Specialized applications

d. Business suites

3. This primary purpose of this type of software is to create text-based documents.

a. Web development

b. word processing

c. spreadsheet

d. presentation

4. Organiztions create newsletters, manuals, and brochures with this type of software.

a. presentation b, graphics c. spreadsheet d. word processing

5.Letters, memos, term papers, reports, and contracts are all examples of

a.. menus

b. models

c. spreadsheets

d. documents

6. Numbers and formulas entered in a cell are called

a.. numeric entries

b. intersection

c. labels

d. text

7. The acronym DBMS stands for what?

a. document binder management system

b. database management system

c. double-blind management setup

d. dam binding and marketing structure

8. Database____ are primarily used to enter new records and to make changes to existing records.

a. table

b. forms

c. queries

d. reports

9.A file that includes predefined settings that can be used to create many common types of presentations is called a

a. pattern

b. model

c. template

d. blueprint

10. A(n)__is a single program that provides the functionality of a word processor,spreadsheet, database manager, and more.

a. software suite

b. integrated package

c. specialized application

d. basic application

88页

a. analytical

b. cell

c. integrated package

d. range

e. relational database

f. software suite

g. sort h. spelling checker i. what-if analysis j. window

1. Area that contains a document, program or message..

2. Type of graph or chart.

3. Includes the functionality of a word processor, spreadsheet, database manager, and more

4. Identifies incorrectly spelled words and suggests alternatives.

5. The intersection of a row and column in a spreadsheet

6. A collection of two or more cells in a spreadsheet

7. Spreadsheet feature in which changing one or more numbers results in the automatic recalculation related fields. ,,

8. Database structure that organizes data into related tables.

9. Arranging objects numerically or alphabetically

10. Individual applications that are sold as a group

115页

1.Graphic programs widely used in the graphic arts profession include

a. desktop publishing programs, image

b. artficial intelligence ,virtual reality, and illustration programs

c. megamedia programs, image editors, and desktop publishing programs

d. virtual reality, desktop publishing programs, and illustration programs

2. Image editors are used' for creating and editing

a. bitmap images

b. vector images

c. text

d. HTML codes

3. Protrams used to create or modify vector images are called

a. illustration programs

b. image editors

c. graphical modifiers

d. bit publishing packages

4.pages in a multimedia presentation typically provide ~ or connections to related

a. blogs

b. links

c. logs

d. maps

5. when determining the overall objective of a multimedia project, the resources required,and the people who will work on the project, you are in the __ step.

a. planning

b. designing

c. creating

d. supporting

6. Many individuals create their own personal sites called Web logs, or

a. flobs

b. blogs

c. buds

d. fellows

7. A special effect in which one image seems to melt into another is referred to as

a. drifting

b. flashing

c. morphing

d. polling

https://www.wendangku.net/doc/992216396.html,er can interact in a fully immersed 3-D environment using __

a. unstructured problems

b. virtual reality

c. VRML

d. robotics

9. Fuzzy logic is

a. use to respond to questions in a humanlike way

b. a new programming language used to program animation

c. the result of fuzzy thinking

d. a term that indicates logical values greater than one

10. Robots used in automobile plants would be classified as

a. perception system robots

b.industrial robots

c. mobile robots d, knowledge robots

116页

a. AI

b. bitmap

c. desktop publishing

d. fuzzy logic

e. graphical map

f. graphics suite

g. image editor h. morphing i. multimedia J. vector image

1. integrates all sorts of media into onepresentation .

2. Graphics program for creating and editing bitmap images.

3. Programs used to create multimedia presentations

4. Diagram of a Web site's overall design

5. Program that allows you to mix text and graphics to create publications of professional quality.

6. Group of graphics programs offered at lower cost than if purchased separately.

7. Special effect in which one image seems to melt into another.

8. Graphics file made up of thousands of pixels

9. Graphics file made up of a collection of objects,such as rectangles, lines, and ovals

10.Attempts to develop computer systems that mimic or simulate human thought processes and actions

143页

1.Software that allows your computer to interact with the user, applications, and

hardware is called

a, application software c,, system software

b. word processor d. database software

2, In order for a computer to understand a program, it must be converted into machine

language by a(n) .

a. operating system c. device driver

b. utility d. language translator

3. ~GUI" stands for

a. gnutella universal interface c. graphical user interface

b. graphic uninstall/install d. genera] utility interface

4, To connect several computers together, one generally needs to be running a(n) operating system.

L network c. stand-alone

b. Internet d. embedded

$. __ is the most widely used operating system.

a. Windows c. UNIX

b. Mac OS d. Linux

6. This operating system is most popular with graphic designers and those who work

in multimedia.

a. Windows XP c. Mac OS

b~ Linux d. UNIX

7. This operating system was originally designed to run on minicomputers used in a

network environment.

a, Linux c. Windows

b. UNIX d. Mac OS

8, These programs guard your computer against malicious programs that may invade your computer system.

L file compression program c. backup program

b. antivirus program tL troubleshooting program

9. A concentric ring on a hard disk is referred to as a

a, track c. table

b. ,sector d. segment

10. Ever).' time the computer system is ,,tarred, the operating system loads these into

memory~

a. driver updates c. device drivers

b, device managers d. Windows updates

144页

a. desktop OS

b. embedded OS

c. file compression program

d. Leopard

e. Linux

f. multitasking

g. NOS

h. platform L system software j. track

1. Concentric ring on a disk.__

2. A version of Mac Os X.__

3. A computer's ability to run more than one application at a time.

4. Operating systems completely stored within ROM.

5. Operating system used to control and coordinate computers that are linked together

6. Another name for software environment.

7. An operating system located on a single stand-alone hard disk.

g. One popular, and free, version of the UNIX operating system.

9. Collection of programs that handle technical details.

10. Program that reduces the size of files for efficient storage.

174页

1' The container that houses most of the electronic components that make a computer ~ system is known as the

a. arithmetic-logic unit c. primary storage unit

b. central processing unit d. system unit

2. The smallest unit in a digital system is a

a. byte c. word

b. bit d. character

3. The communications medium for the entire computer system is the

a. arithmetic-logic unit c. motherboard

b. semiconductor d. coprocessor

4. These provide expansion capability for a computer system.

a. sockets c. ports

b. slots d. bays

5. The __ tells the rest of the computer how to carry out a program's instructions.

a. ALU c. system unit

b. control unit d. motherboard

6. A 32-bit word computer can access __ bytes at a time.

a. 4 e. 16

b. 8 d. 32

7. These chips are specifically designed to handle the processing requirements related to

displaying and manipulating 3-D images.

a. graphics coprocessors c. control unit processors

b. arithmetic-logic unit processors d. CISC chips

8. This type of memory improves processing by acting as a temporary high-speed holding

area between the memory and the CPU.

a. RAM c. cache memory

b. ROM d. flash memory

9. is a set of hardware and software standards.

a. CPU c. cache

b. Plug and Play d. ALU

10. ports connect special types of music instruments to sound cards.

a. BUS c. USB

b. CPU d. MIDI

a. bus widlh

b. cables

c. control unit

d. expansion card

e. PC card

f. port

g. RAM h. smart card i. system clock j. system unit

1. Houses most of the electronic components in a computer system --

2. The number of bils that can travel down a bus at the same time

3. Tells the computer system how to carry out a program's instructions,

4. A credit card-sized piece of plastic with an embedded chip.

5. Volatile storage that holds the program and data the CPU is currently processing.

6. Produces precisely timed electrical beats as a timing mechanism. __

7. Plugs into slots on the system board.

8. Credit card sized expansion boards used by portable computers. __

9. Connecting socket on the outside of the system unit. __

10. Connects input and output devices to the system unit via the ports. __

207页

1, Hardware used to translate words, sounds, images, and actions,that people understand into a form that the system unit can process is known as

a. input devices c. device reader'~

lb. output devices d. device drivers

2. This type of keyboard provides the greatest amount of flexibility and convenience by

eliminating cables connected to the system unit.

a. ergonomic keyboard c. traditional keyboard

b. wireless keyboard d. flexible keyboard

3. The mouse_ usually appears in the shape of an arrow.

a. pointer c. indicator

b. marker d. meter

4. This type of pointing device is located in the middle of the keyboard.

a. joystick c. wireless

b. pointing stick d. light pen

5. This type of pointing device has crisscrossed invisible beams of infrared light that are

protected with a clear plastic outer layer.

a. optical mouse c. pointing stick

b. light pen d. touch screen

6. A Universal Product Code is read by what type of scanner?

a. bar code c. OCR

b. flatbed d. MICR

7. ~ input devices convert sounds into a form that can be processed by the system unit

a. Electrolyzing c. WebCarn

b. Plotting d. Audio

8. The most important characteristic of a monitor is its

a. dot pitch c. clarity

b. resolution d. viewable size

9. Which of the following printer types requires special paper?

a. chain c. ink-jet

b. laser d. thermal

10. ____ is a specialized input and output device for receiving and sending voice

communication.

a. Fax machine c. Network terminal

b. Internet telephone d. PDA

207页

a. clarity

b. CRT

c. dpi

d. HDTV

e. joystick

f. stylus

h. thermal L toggle ]. UPC

1. These keys turn a feature on or off. __

2. A pointing device widely used for computer games. --

3. Penlike device commonly used with tablet PCs and PDAs. __

4. ~ of bar code used in supermarkets. --

5. Refers to quality and sharpness of displayed images.

6.Type of monitor similar to a traditional television set.

7. Monitors that have independently activated pixels. __

g. Delivers a much clearer wide-screen picture than regular television. --

9, Measurement used to determine a printer's resolution.

10. Printer that uses heat to produce images on heat sensitive paper __

235页

1. Primary storage is referred to as __ storage.

a. volatile c. direct

b. sequential d. nonvolatile

2. The amount of time required by a storage device to retrieve data and programs is its

a. access speed c. memory

b. capacity d. storage

3. How tightly the bits can be packed next to one another on a disk is referred to as

a. tracks c. density

b. sectors d. configuration

4. Thick, rigid metal platters that are capable of storing and retrieving information at a

high rate of speed are known as

a. hard disks c. cartridges

b. soft disks d. packs

5. The data on an optical disc is represented by flat areas called on the disc surface.

a. surfaces c. lands

b. flats d. pits

6. A CD-ROM disc

a. cannot be erased and rewritten c. holds less data than a floppy disk

b. has more storage capacity than a CD-R d. can be written to only once

7. DVD stands for

a. digital video data c. digital versatile disc

b. direct video disc d. direct versatile disc

8. This type of storage device has no moving parts.

a. hard disks c. optical discs

b. floppy disks d. solid state

9. Tape is described as using this type of access.

a. magneto-optical c. direct

b. DVD d. sequential

10. Specialized high-capacity secondary storage device designed to meet organizational

demands for data.

a. Blue-Ray c. mass storage

b. hi def d. Zip disk

235页

a. access speed

b. file compression

c. flash memory card

d. hard-disk pack

e. hi def

f. Internet hard drive h. solid-state storage i. track j. Zip disk

1. A type of storage that is volatile. --

2. Time required to retrieve data and programs. --

3. A high-capacity floppy disk. __

4. Closed concentric ring on a disk on which data is recorded. __

S. Several platters aligned one above the other, allowing greater storage capacity. __

6. Increases storage capacity by reducing the amount of space required to store data and

programs

7. Stores data electronically and has no moving parts. __

8. Solid-state storage device used in portable computers. __

9. Free or low-cost storage available at special service Web sites. --

10. The next generation of optical discs. –

305页

1. The standards of moral conduct that control how computers are used are called

a. ethics c. security requirements

b. laws d. business demand~

2. The ethical issue that involves who is able to read and use data is

a. access c. accuracy

b. property d. privacy

3. Two types of cookies are __

a. advanced and remedial c. natural and ad network

b. traditional and natural d. ad network and traditional

4. People who gain unauthorized access to computers for the fun of it, but do not

intentionally do damage, are __

a. employees c. crackers

b. hackers d. members of organized crime

5. A program that migrates through networks and operating systems by attaching itself to

different programs and databases is a __

a. virus c. denial-of-service attack

b. worm d. Web bug

6. An attempt to slow down or stop a computer system or network by flooding the system

with requests for information is called a

a. virus c. denial-of-service attack

b. worm d. Trojan horse

7. Secret words or numbers used to gain access to a computer system are called

a. encryption c. crackers

b. codes d. passwords

8. One of the more common types of technological failures is when your computer

experiences too much electricity. This is known as __

a. a protector c. a voltage surge

b. a brownout d. energizing

9. __ is the study of human factors relating to things people use

a. EPA c. encryption

b. ergonomics d. privacy

10. The computer industry response to the Energy Star program is the

a. CFC Association e. Freedom of Information Act

b. EncryptionAct d. Green PC

305页

a. ad network cookies

b. computer crime

c. cracker

d. DoS

e. firewall

f. illusion of anonymity

g. property h, snoopware i virus checkers j. worm

I. Relates to who owns data and rights to software. __

2. Programs that record virtually every activity on a computer system. __

3. Belief that there is little threat to personal privacy via the Internet. __

4. Monitor Web activity and send repot ts to marketing groups. --

5. Illegal action involving special knowledge of compute technology. __

6. Gains unauthorized access to a system for malicious purposes. __

7. Fills a computer system with self-replicating information.

8. An attack that overwhelms Web sites with data, making them inaccessible. __

9. Programs that alert users when certain viruses enter a system. __

10. Security hardware and software that controls access to internal computer networks. –

331页

a. DSS

b. exception report

c. GDSS

d. general ledger

e. knowledge Workers

f. MIS

g. periodic report

h. supervisor

i. tactical models J. TPS

I. Manager responsible for administration and monitoring workers

2. System that records day-to-day transactions ~

3. Computer-based information system that produces standardized reports in summarized, structured form,

4. Activity that produces income statements and balance sheets based on all transactions of a company

5. Repot1 generated at regular intervals

6. Report that calls attention to unusual events ____

7. Flexible tool for analysis that helps manager make decisions about unstructured problems. --

8. System used to support the collective work of a team addressing large problems, --

9. Models that help middle managers control the work the organization. --

10. Individuals involved in the creation of information.

361页

a. data dictionary

b. DBMS engine

c. file

d. key field

e. logical

f. multidimensional

g. network database h. SOL i. real-time processing j. relational database

1. End users ~d most computer professional use this data view. __

2. A collection of records.

3. The common field by which tables m a database are related.

4. Processing that occurs where data is processed when the transaction occurs. __

5. Software required to create, modify', and gain access to a database.

6. Dictionary ~ith a description of the data structure in a database --

7. Most widely used query language.

8. Database with hierarchical arrangement of nodes in which each child node may have more than one parent node. __

9. Database structure in which data is organized into related tables. __

10. DBMS su'ucture that extends the two-dimensional relational data model. –

393页

1.In which phase of the systems life cycle are information needs identified?

a. preliminary investigation c. systems implementation

b, systems design d. systems maintenance

2, This phase of the systems life cycle is known as the "ongoing phase," where the system is periodically evaluated and updated as needed.

It. preliminary investigation c. systems implementation

b, systems design d. systems maintenance

3. Which of the following shows levels of management and formal lines of authority?

a, organization chart c. pyramid diagram

b. decision table d. grid chart

4, Which of the following is r~0t found on a data flow diagram?

a. entities c. locations

b. process d. file

5. Which of the following tasks is not part of the systems design phase?

a. designing alternative systems c. writing a systems design report

b. selecting the best system d. suggesting alternative solutions

6. Determining if employees, managers, and clients will resist a proposed new system is

part of this feasibility study.

a. technical feasibility c. organizational feasibility

b. economic feasibility d. operational feasibility

7. The __ approach conversion type simply involves abandoning the old system and

using the new

a. direct c. phased

b. pilot d. parallel

8, In the implementation approach, the new system is broken down into smaller parts that are implemented over time.

a. pilot c. parallel

b, direct d. phased

9. The ongoing testing and analysis of an existing system is called systems

a. maintenance c. design

b. implementation d, analysis

10. Which of the following is a disadvantage to prototyping?

L quick user feedback c. difficult to manage

b. lengthy development times d. lack of user feedback

393页

a. data flow diagram

b. economic feasibility e. grid chart d. organization chart

e. phased approach

f. preliminary investigation

g. systems anal)sis and design

h. systems analyst L systems design report j. systems development

1. Six-phase procedure for examining and improving information systems. __

2. Computer professional who studies an organization's systems.

3. The first phase of the systems life cycle. __

4. Chart showing management levels and format lines of authority. __

g. Shows the relationship between input and output documents.

6. Shows the data or information flow within an information system. --

7. Condition where cost of designing a system is justified by the benefits.

8. Report for higher management describing the alternative designs suggested in the design phase.

9, Phase consisting of developing software, acquiring hardware, and testing the new system. __ 10. Implementation gradually over a period of time. __

451页

1.Change in technology require people who

a. think every piece of equipment is so simple they can just turn it on and use it

b. know just the basics about the technology

c. think each new machine is a potential disaster

d. are not afraid to learn and manage new technology

2. One of the advantages of the changes in information technology

a, people are put out of work c. data can be lost and/or stolen

b. new businesses are created d. new skills are constantly m demand

3. The __ user believes that learning and using computers take time away from his or her real

job.

a. cynical c. frustrated

b. proactive d. naive

4. Generally, a proactive person

a. feels that the idea of using a c. hates to take time to learn about

microcomputer is overrated microcomputers

b. is unfamiliar with computers d. looks at technology in a positive, realistic way

5. To maintain your computer competence, you should try to stay ahead of technology by

a. learning a new trade c. reading books, journals, newspapers

b. reviewing the systems life cycle and magazines

d. quiting your current job and going back to school

6. Successful people make it a point to

a. develop nonspecific skills c. get their education and relax

b. avoid contact with others d. maintain contact with others in their filed

7. These individuals design, test, and research encryption procedures.

a. database administrator c. cryptographer

b. technical writer d. computer trainer

8. __ oversee the work of programmers, computer specialists, and other computer professionals.

a. Systems analysts c. Information systems managers

b. Database administrators d. Network managers

9. These individuals are responsible for creating, testing, and troubleshooting computer

programs.

a. systems analysts c. network managet~

b. database administrators d. programmers

10. ___develop and maintain Web sites and Web resources.

a. System analysts c. Network managers

b. Webmaster d. Programmers

451页

a.database administrator computer technician c. computer trainer d. cynic

e. software engineer

f. technical writer

g. network administrator h programmer

i systems analyst J. Webmaster

1. Computer user who feels the idea of using microcomputers overrated. __

2. A computer specialist employed to evaluate, create, and maintain Web sites. --

3. Computer professional who creates, tests, and troubleshoots computer programs. __

4. Computer specialist who uses datable management software to determine the most efficient ways to organize and access dam. __

5. Computer professional who an analyzes uses' needs and creates application software. __

6. Computer professional who plans and designs information systems.

7. Computer professional who plans and installs computer components and systems --

8. Computer professional who creates and maintains networks. __

9. Computer professional who instructs users on the latest software or hardware. __

10. Computer professional who prepares ins4rucfion manuals, technical reports, and other scientific or technical documents. --

计算方法引论课后答案.

第一章误差 1. 试举例,说明什么是模型误差,什么是方法误差. 解: 例如,把地球近似看为一个标准球体,利用公式2 4A r π=计算其表面积,这个近似看为球体的过程产生的误差即为模型误差. 在计算过程中,要用到π,我们利用无穷乘积公式计算π的值: 12 222...q q π=? ?? 其中 11 2,3,... n q q n +?=?? ==?? 我们取前9项的乘积作为π的近似值,得 3.141587725...π≈ 这个去掉π的无穷乘积公式中第9项后的部分产生的误差就是方法误差,也成为截断误差. 2. 按照四舍五入的原则,将下列各数舍成五位有效数字: 816.956 7 6.000 015 17.322 50 1.235 651 93.182 13 0.015 236 23 解: 816.96 6.000 0 17.323 1.235 7 93.182 0.015 236 3. 下列各数是按照四舍五入原则得到的近似数,它们各有几位有效数字? 81.897 0.008 13 6.320 05 0.180 0 解: 五位三位六位四位 4. 若1/4用0.25表示,问有多少位有效数字? 解: 两位 5. 若 1.1062,0.947a b ==,是经过舍入后得到的近似值,问:,a b a b +?各有几位有效数字? 解: 已知4311 d 10,d 1022 a b --

计算机科学导论课后练习

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