相关试题
【单选题】
一台微型计算机的字长为4个字节，它表示___ 。
A. 在CPU中运算的结果为8的32次方
B. 能处理的数值最大为4位十进制数9999
C. 能处理的字符串最多为4个ASCⅡ码字符
D. 在CPU中作为一个整体加以传送处理的二进制代码为32位
【单选题】
计算机病毒主要是造成 ___ 破坏。
A. 软盘
B. 磁盘驱动器
C. 硬盘
D. 程序和数据
【单选题】
发现病毒后，比较彻底的清除方式是___ 。
A. 格式化磁盘
B. 删除磁盘文件
C. 用杀毒软件处理
D. 用查毒软件处理
【单选题】
防病毒卡能够 ___ 。
A. 杜绝病毒对计算机的侵害
B. 自动消除已感染的所有病毒
C. 自动发现病毒入侵的某些迹象
D. 自动发现并阻止任何病毒的入侵
【单选题】
照查继电器电路中,ZCJ设置在 ___ 。
A. 只设置在1LXF中
B. 只设置在2LXF中
C. 设置在1LXF或2LXF中
D. 设置在LXZ或1LXZ或2LXF中
【单选题】
只有___ 的按钮才能兼作相反方向的调车进路的变通按钮。
A. 单置调车信号机
B. 并置调车信号机
C. 差置调车信号机
D. 通过信号机
【单选题】
只有在变通进路上没有调车按钮可兼作变通按钮的情况下，才特设一个___ 。
A. 变通按钮
B. 单置调车按钮
C. 并置调车按钮
D. 差置调车按钮
【单选题】
方向电源，例如“KZ-共用-H”是通过四个方向继电器后接点和___ 后接点接通的正极性电源。
A. ZQJ
B. ZRJ
C. 1RJJ
D. 2RJJ
【单选题】
有两个离去区段都空闲,出站信号机点亮绿灯时 ___ 。
A. LXJ↓、DXJ↓、DJ↑
B. LXJ↑、DXJ↑、DJ↓
C. LXJ↑、ZXJ↑、2LQJ↑、DJ↑
D. LXJ↓、DXJ↑、DJ↑
【单选题】
在KJ3-4线圈的电路中，通过一个___ 第七组接点接入负极性电源。
A. JXJ
B. XJJ
C. JYJ
D. ZJ
【单选题】
6502电气集中，___ 是选择究竟哪一个区段可以锁闭和为解锁做准备的。
A. FKJ
B. QJJ
C. 进路继电器
D. SJ
【单选题】
6502电气集中， ___ 是专门检验解锁条件的。
A. FKJ
B. QJJ
C. 进路继电器
D. SJ
【单选题】
6502电气集中，___ 是反映进路在锁闭状态或解锁状态用的。
A. FKJ
B. QJJ
C. 进路继电器
D. SJ
【单选题】
在整个网络中，对每条具体进路的电路来说，进路的区分用 ___ 接点确定。
A. DBJ或FBJ
B. DCJ或FCJ
C. 1LJ或2LJ
D. DBJ
【单选题】
当道岔在转换或发生挤岔故障，停电或断线等故障时，必须保证DBJ和FBJ落下，因此必须使用 ___ 。
A. 安全型继电器
B. 有极型继电器
C. 电码型继电器
D. 非安全型继电器
【单选题】
在ZQJ与ZRJ的线圈上都并联有电容C和电阻R，其作用是为了使继电器有___ 左右的缓放时间。
【单选题】
在办理取消进路和人工解锁时，要求___ 在进路未解锁以前一直保持吸起。
A. XJ
B. QJ
C. ZQJ
D. ZRJ
【单选题】
ZCJ失磁落下后，只有进路中___ 解锁，才能使ZCJ复原。
A. 最末一个区段道岔
B. 第一个区段道岔
C. 最末一个区段
D. 第一个区段
【单选题】
6502电气集中控制台零层18柱端子第10端子的用途 ___ 。
A. 道岔按扭CA-12接点
B. 列车按钮LA-12接点
C. 调车按钮DA-12接点
D. 按钮表示灯L灯
【单选题】
选平行进路要用 ___ 。
A. 分线法
B. 断线法
C. 选岔电路
D. 选路法
【单选题】
6502电气集中，___ 是用来区分黄与双黄显示的。
A. ZXJ
B. TXJ
C.
D. XJ D. LXJ
【单选题】
6502电气集中，___ 是用来区分绿与黄的显示。
A. ZXJ
B. TXJ
C.
D. XJ D. LXJ
【单选题】
CTCS-2车站列控中心设备接地电阻一般不大于 ___ 。
【单选题】
CTCS-2车站列控电源屏供电电压应在AC220V～ ___ 内。
A. 230V
B. 235V
C. 240V
D. 250V
【单选题】
微机的性能指标中的内存容量是指 ___ 。
A. RAM的容量
B. RAM和ROM的容量
C. 软盘的容量
D. ROM的容量
【单选题】
计算机的CPU每执行一个 ___ ，就完成一步基本运算或判断。
【单选题】
计算机能按照人们的意图自动、高速地进行操作，是因为采用了___ 。
A. 程序存储控制
B. 高性能的CPU
C. 高级语言
D. 机器语言
【单选题】
当交流电压为198V（直流电压为19.5V），移频发送盒负载电阻为3.3Ω时，功放输出电压应不小于 ___ 。
A. 5.6V
B. 6V
C. 13V
D. 16.2V
【单选题】
操作系统的主要功能是 ___ 。
A. 进行数据处理
B. 实现软、硬件转换
C. 把源程序转换为目标程序
D. 管理系统所有的软、硬件资源
【单选题】
下面关于ROM的说法中，不正确的是 ___ 。
A. CPU不能向ROM随机写入数据
B. ROM是只读存储器的英文缩写
C. ROM中的内容在断电后不会消失
D. ROM是只读的，所以它不是内存而是外存
【单选题】
在下面关于字符之间大小关系的说法中，正确的是 ___ 。
A. 空格符>b>B
B. 空格符>B>b
C. b>B>空格符
D. B>b>空格符
【单选题】
汉字系统中的汉字字库里存放的是汉字的 ___
A. 机内码
B. 输入码
C. 字形码
D. 国标码
【单选题】
滤波电路中整流二极管的导通角较大，峰值电流很小，输出特性较好，适用于低电压、大电流场合的滤波电路是___ 。
A. 电感式
B. 电容式
C. 复式
D. 有源
【单选题】
光盘驱动器通过激光束来读取光盘上的数据时，光学头与光盘 ___ 。
A. 直接接触
B. 不直接接触
C. 播放VCD时接触
D. 有时接触有时不接触
【单选题】
移频电源检测盒的报警电路是由四个电压检测电路和四个光电耦合器组成的___ 电路构成的。
A. 与门
B. 与非门
C. 或门
D. 异或门
【单选题】
为了满足移频接收设备采用双机并联运用，必须在限放前增加一级___ 电路。
A. 放大
B. 反相
C. 射级跟随器
D. 阻容耦合
【单选题】
双稳态触发器的返还系数一般要求大于 ___ ，此值越大，设备的抗干扰能力越强。
A. 75%
B. 85%
C. 90%
D. 95%
【单选题】
移频地面发送设备，当交流电压在220±22V范围内变动时，载频漂移不大于___。
A. ±3Hz
B. ±4Hz
C. ±5Hz
D. 9Hz
推荐试题
【单选题】
The survey by the Kaiser Family Foundation is mentioned to illustrate the idea that . ___
A. kids don’t always follow parents’ rules
B. only few parents believe the good news
C. much media use results in bad health
D. parents’ rules make a huge difference
【单选题】
What did the kids do when parents set any time or content limits, according to the Kaiser Family Foundation? ___
A. They cut down on their screen time.
B. They appreciated their parents’ love.
C. They spent more time staying outdoor.
D. They accepted parents’ rules unwillingly.
【单选题】
What will Kenneth Ginsburg most probably suggest that parents should do? ___
A. Avoid setting firm rules.
B. Avoid ruling with an iron grip.
C. Set rules after family discussion.
D. Set rules that are easy to understand.
【单选题】
Margaret Broe -Fitzpatrick finds it impossible. ___
A. to achieve just- right parenting
B. to keep track of everything done by the kids
C. for the kids to face rules alone
D. for the kids to observe rules without protest
【单选题】
The passage is mainly intended for parents . ___
A. whose kids have difficulty in self- discipline
B. whose kids are addicted to media use
C. who have doubts about setting rules
D. who are too busy to care for their kids
【单选题】
The word “it” (Para. 2) most probably refers to. ___
A. the lack of stable communities
B. the breakdown of informal information channels
C. the increased mobility of families
D. the growing number of people moving from place to place
【单选题】
The main problem people may encounter today arises from the fact that . ___
A. they have to learn new things consciously
B. they lack the confidence of securing reliable and trustworthy information
C. they have difficulty obtaining the needed information readily
D. they can hardly carry out casual communications with an extended family
【单选题】
From the passage we can infer that _______. ___
A. electronic mail will soon play a dominant role in transmitting messages
B. it will become more difficult for people to keep secrets in an information era
C. people will spend less time holding meetings or conferences
D. events will be reported on the spot mainly through satellites
【单选题】
Technology facilitates _______. ___
A. sharing information
B. storing and sending information
C. providing people with easy access to more information
D. all of the above
【单选题】
We can learn from the last paragraph that _______. ___
A. it is necessary to obtain as much
B. people should make the best use of the information
C. we should realize the importance of accumulating information
D. it is of vital importance to acquire needed information efficiently
【单选题】
The author thinks that people are _________. ___
A. satisfied with their appearance
B. concerned about appearance in old age
C. far from neglecting what is in fashion
D. reluctant to follow the trends in fashion
【单选题】
Fashion magazines and TV advertisements seem to link fashion to _________. ___
A. confidence in life
B. personal dress
C. individual hair style
D. personal future
【单选题】
Causes of fashions are _________. ___
A. uniform
B. varied
C. unknown
D. inexplicable
【单选题】
Present-day society is much freer and easier because it emphasizes _________. ___
A. uniformity
B. formality
C. informality
D. individuality
【单选题】
Which is the main idea of the last paragraph? ______________ ___
A. Care about appearance in formal situations.
B. Fashion in formal and informal situations.
C. Ignoring appearance in informal situations.
D. Ignoring appearance in all situations.
【单选题】
Permissive parents would ________. ___
A. let their children read any books they like to
B. not let their children see any films they like to
C. not let their children read any books without first checking their contents
D. let their children see the films with their first checking
【单选题】
The fact that parents check the contents of the book or the film for their children to read or see shows __________. ___
A. the necessity of censorship
B. that many books and films are bad
C. that children need their parents to help them understand more
D. that the parents are permissive
【单选题】
Which of the following statements is NOT true?____________ ___
A. Some adults can’t tell right from wrong.
B. Censorship is compared to the law because both of them perform good service to society as a whole.
C. Censors pay attention only to genuine works of art.
D. Censorship is necessary because many books, plays and films are far from being “works of art”.
【单选题】
What does the word “corrupt” in Para.4 mean?__________ ___
A. Make morally bad.
B. Hurt.
C. Injure.
D. Damage.
【单选题】
What would be the best title of this passage?_____________ ___
A. Permissive Parents and Responsible Parents.
B. Censorship and the Law.
C. Censors Value Artistic Merits .
D. Censorship Performs Good Service to Society.
【单选题】
Lie detectors are widely used in the United States because _____________. ___
A. they can help detect people’s emotional stress
B. they can help detect people's physiological changes
C. they can help find out whether a person is telling the truth or not
D. they can measure the subject’s electrical resistance
【单选题】
According to the passage, we know that Britain______________. ___
A. will adopt lie detectors widely
B. will adopt lie detectors on a smaller scale
C. adopt lie detectors
D. has not decided whether to adopt lie detectors or not
【单选题】
The tests themselves are by no means free from error..." (Line 1-2.Para.3) means ____________. ___
A. the tests definitely have no error
B. the tests sometimes make mistakes
C. the polygraphers do not make mistakes
D. the polygraphers can avoid error by using some techniques
【单选题】
Which of the following is true? ________________ ___
A. The tests are conducted by qualified polygraphers.
B. Innocent people may blush or stammer when questioned.
C. Guilty people can definitely be found out by answer questions
D. Guilty people may escape by refusing to answer questions.
【单选题】
What troubles lie detector researchers most is that _______________. ___
A. innocent people are convicted crimes
B. innocent people will learn to tell lies
C. lie detectors may cause industrial unrests
D. lie detectors are sometimes not dependable
【单选题】
In the passage the author's attitude towards "mixed-ability teaching" is _______. ___
A. critical
B. questioning
C. approving
D. objective
【单选题】
By "held back" (Line 1) the author means _____. ___
A. made to remain in the same classes
B. forced to study in the lower classes
C. drawn to their studies
D. prevented from advancing
【单选题】
The author argues that a teacher's chief concern should be the development of the student's _________. ___
A. personal qualities and social skills
B. total personality
C. learning ability and communicative skills
D. intellectual ability
【单选题】
Which of the following is NOT MENTIONED in the third paragraph? __________ ___
A. Group work gives pupils the opportunity to learn to work together with others.
B. Pupils also learn to develop their reasoning abilities.
C. Group work provides pupils with the opportunity to learn to be capable organizers.
D. Pupils also learn how to participate in teaching activities.
【单选题】
The author's purpose in writing this passage is to ______. ___
A. argue for teaching bright and not-so-bright pupils in the same class
B. recommend pair work and group work for classroom activities
C. offer advice on the proper use of the library
D. emphasize the importance of appropriate formal classroom teaching
【单选题】
According to the author, the deaths among youth are mainly caused by _____. ___
A. traffic accidents
B. smoking-related diseases
C. murder
D. all of these
【单选题】
Every day there are over_____high school students who will become regular smoker. ___
A. 75
B. 23
C. 30
D. 3000
【单选题】
By "dropout" the author means______. ___
A. students who failed the examination
B. students who left school
C. students who lost their way
D. students who were driven out of school
【单选题】
The reason for declining adolescent smoking is that ________. ___
A. NCI has taken effective measures
B. smoking is prevented among high school seniors
C. there are many smokers who have died of cancer
D. not stated
【单选题】
What is implied but not stated by the author is that ________. ___
A. smoking rates among youth have declined very little
B. there are now more female than male smokers among high school seniors
C. high smoking rates are due to the increase in wealth
D. smokers at high school are from low socio-economic backgrounds
【单选题】
According to the passage, which of the following is NOT a disadvantage of part time education? _______________ ___
A. It requires some break in one's career.
B. It tends to last too long for many people to complete a degree program.
C. It affects one's career.
D. It gives the student less time to share with the family.
【单选题】
Which of the following is NOT an advantage of distance learning? _________ ___
A. The student may choose his or her own pace.
B. The student may study at any time to his or her convenience.
C. They can pursue their chosen career while studying.
D. Their tutorial assistance comes through regular airmail, telephone, etc.
【单选题】
What benefit will distance learning program bring to a business? __________ ___
A. Recruitment of more talented people.
B. Good image of the business.
C. Better cooperation with universities.
D. Further training of employees and business growth.
【单选题】
Good distance learning program have the following characteristic EXCEPT______. ___
A. distance learning course is the same as students taking courses in campus
B. the degree should be same as on campus study
C. professor-student relationship is strictly one to one all through the course
D. includes subject evaluation tool
【单选题】
What benefit will distance learning bring to an employee of a business? ___________ ___
A. Professional growth.
B. Good relationship with the employer.
C. Good impression on the employer.
D. Higher salary.
