【单选题】
CTCS-2车站列控中心机柜UPS持续供电时间不小于_______。[332010104]___
A. 20min
B. 25min
C. 30min
D. 50min
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答案
C
解析
暂无解析
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CTCS-2列控地面设备阿尔斯通LEU电源板为整个LEU提供电源，输入标称电压为DC_______。[331050203]___
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ZD6型电动转辙机表示杆移动_______(推或拉，在检查柱与检查块每侧间隙为1.5mm条件下)，动接点应退出静接点组，切断表示电路。[331010204]___
A. 5.7mm～7.5mm
B. 5.7mm～8mm
C. 5.7mm～8.5mm
D. 5.7mm～9mm
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【单选题】
对于移频设备站内发送盒与区间发送盒，以下说法中_______是正确的。[321010103]___
A. 原理不相同，功放级相同
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C. 原理和功放级都相同
D. 原理相同，功放级不相同
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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_______。[321010103]___
A. ±3Hz
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D. 9Hz
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移频衰耗器初级线圈1、2的输入阻抗Z1为4Ω～4.5Ω，当RT从0变到∞时，此值变化范围在_______之间。[321010103]___
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当交流电压为242V(直流电压为24.5V)，移频发送盒负载电阻为0.85Ω时，功放输出电压应不小于_______。[321010101]___
A. 2.1V
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【单选题】
ZP·W1-18型无绝缘移频自动闭塞设备，通过发送、接收电缆盒的电缆补偿，使实际电缆长度与模拟电缆长度之和为_______，以利于移频信号的传输和调整。[312010103]___
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【单选题】
ZD9转辙机当滚轮在动作板上滚动时，启动片尖端离开速动片上平面的间隙应为_______。[312010204]___
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B. 0.5mm～1.7mm
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ZD9转辙机当锁闭杆从终端往回移动，锁闭杆斜面与检查柱斜面接触后，锁闭杆再移动_______时，表示接点组应可靠断开开关的常闭接点。[331010204]___
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载频中心为550Hz时，移频波的能量主要分布在495Hz、605Hz频率的附近，这说明频偏为_______。[321010103]___
A. 50Hz
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继电半自动闭塞电源停电恢复时，只有用_______办理，方能使闭塞机恢复。[333030204]___
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继电半自动闭塞采用架空线时，其直流电阻经运用腐蚀后最大不超过_______。[331010103]___
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C. 13.7Ω
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【单选题】
自动站间闭塞,当列车出发后,闭塞解除前,两站向该区间的出站信号机_______。[322030204]___
A. 不得再次开放
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【单选题】
自动站间闭塞,列车到达接车站,经过检查区间空闲后,闭塞_______。[322000000]___
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ZD6转辙机速动爪与速动片的间隙，在锁闭时为_______。[321010204]___
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According to one study, what do green spaces do to people? ___
A. Improve their work efficiently.
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What does Dr. White say people usually do to make themselves happier? ___
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What does Dr. White try to find out about living in a greener urban area? ___
A. How it affects different people.
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What did Dr. White’s research reveal about people living in a green environment? ___
A. Their stress was more apparent than real.
B. Their decisions required less deliberation.
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According to Dr. White, what should the government do to build more green spaces in cities? ___
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The survey by the Kaiser Family Foundation is mentioned to illustrate the idea that . ___
A. kids don’t always follow parents’ rules
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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.
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D. They accepted parents’ rules unwillingly.
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What will Kenneth Ginsburg most probably suggest that parents should do? ___
A. Avoid setting firm rules.
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【单选题】
Margaret Broe -Fitzpatrick finds it impossible. ___
A. to achieve just- right parenting
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【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
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【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
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The main problem people may encounter today arises from the fact that . ___
A. they have to learn new things consciously
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C. they have difficulty obtaining the needed information readily
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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
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【单选题】
The author thinks that people are _________. ___
A. satisfied with their appearance
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Fashion magazines and TV advertisements seem to link fashion to _________. ___
A. confidence in life
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Present-day society is much freer and easier because it emphasizes _________. ___
A. uniformity
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D. individuality
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Which is the main idea of the last paragraph? ______________ ___
A. Care about appearance in formal situations.
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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
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【单选题】
Which of the following statements is NOT true?____________ ___
A. Some adults can’t tell right from wrong.
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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
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【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
