BTS的时钟使用从Abis口提取的时钟来同步BTS,使用卫星链路来连接Abis时,对

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问题:

BTS的时钟使用从Abis口提取的时钟来同步BTS,使用卫星链路来连接Abis时,对于BTS的时钟源,一般采用BTS()

A.网同步时钟

B.链路时钟同步

C.帧时钟同步

D.内同步时钟

考点:无线电调试工考试无线电调试工综合知识无线电调试工综合知识题库
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已知m mol某气体的质量为a g,则b g该气体在标准状况下的体积(L)为(  )

A.22.4am/b

B.22.4b/am

C.22.4bm/a

D.22.4a/bm

题型:单项选择题

下列关于接口的说法中,正确的是( )。

A.接口之间不能有继承关系

B.一个类不可实现多个接口

C.接口与抽象类是相同的概念

D.实现一个接口必须实现接口的所有方法

题型:单项选择题

颈椎病用枕颌吊带牵引的重量是

A.1~2 kg

B.2~3 kg

C.3~10 kg

D.6~8 kg

E.8~10 kg

题型:单项选择题

The standardized educational or psychological tests, that are widely used to aid in selecting, assigning, or promoting students, employees, and military personnel have been the target of recent attacks in books, magazines, the daily press, and even in Congress. The target is wrong, for in attacking the tests, critics divert attention from the fault that lies with ill-informed or incompetent users. The tests themselves are merely tools, with characteristics that can be measured with reasonable precision under specified conditions. Whether the results will be valuable, meaningless, or even misleading depends partly upon the tool itself but largely upon the user.

All informed predictions of future performance are based upon some knowledge of relevant past performance. How well the predictions will be validated by later performance depends upon the amount, reliability, and appropriateness of the information used and on the skill and wisdom with which it is interpreted. Anyone who keeps careful score knows that the information available is always incomplete and that the predictions are always subject to error.

Standardized tests should be considered in this context. They provide a quick, objective method of getting some kinds of information about what a person has learned, the skills he has developed, or the kind of person he is. The information so obtained has, qualitatively, the same advantages and shortcomings as other kinds of information. Whether to use tests, other kinds of information, or both in a particular situation depends, therefore, upon the empirical evidence concerning comparative validity, and upon such factors as cost and availability.

In general, the tests work most effectively when the traits or qualities to be measured can be most precisely defined (for example, ability to do well in a particular course of training program) and least effectively when what is to be measured or predicted cannot be well defined (for example, personality or creativity). Properly used, they provide a rapid means of getting comparable information about many people. Sometimes they identify students whose high potential has not been previously recognized, but there are many things they do not do. For example, they don’t compensate for gross social inequality, and thus don’t tell how able an underprivileged younger might have been had he grown up under more favorable circumstances.

According to the text, which of the following statements is not true()

A. Predictions do not always hold true

B. Some students "shine" unexpectedly

C. The supervisor of the test must be well trained

D. Personality tests often fall short of their purpose

题型:单项选择题

闸瓦制动器的闸瓦磨损量超过原厚度1/4时,应及时更换。

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