集散控制系统中,顺序控制系统通常集中在几个I/O过程控制站中,启动顺序控制应()。A

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问题:

集散控制系统中,顺序控制系统通常集中在几个I/O过程控制站中,启动顺序控制应()。

A、在操作员站上发指令;

B、根据条件自动执行;

C、定时执行;

D、A、B均可能。

考点:热工程控保护考试热工程控保护技师热工程控保护技师题库
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生活中的下列现象,用分子的相关知识解释不合理的是                  (     )

A.食物变质­­­­­­­­­­­­­­­———分子本身发生变化

B.花香四溢———分子在不停运动

C.热胀冷缩———分子间间隔改变

D.汽油挥发———分子大小发生变化

题型:单项选择题

Come and see me whenever ____ .

A. you are convenient

B.you will be convenient

C. it will be convenient for you

D.it is convenient to you

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如图所示,光滑球重100N,球的半径10cm,绳的一端与球面上C点相连,使球靠在墙上而静止,绳子长10cm,求:球对绳子的拉力和对墙的压力各多大?

题型:单项选择题

But let no one think that pleasure is immoral. Pleasure in itself is a great good, all pleasure, but its consequences may be such (31) the sensible person eschews certain varieties of (32) Nor need pleasure be gross and sensual. They are wise in their generation (33) have discovered that intellectual pleasure is the most satisfying and the most enduring. It is well to (34) the habit of reading. There are (35) sports in which you can engage to your own satisfaction after you have passed the prime of life; there are no games except patience, chess problems and crossword puzzles that you can play without someone to play them with you. Reading suffers (36) no such disadvantages; there is no occupation—except perhaps needle- work, but that leaves the restless spirit (37) liberty—which you can more easily (38) up at any moment, for any period, and more easily put (39) when other calls press upon you; there is no other amusement that can be obtained in these happy days of public liberties and cheap editions at so small a (40) . To acquire the habit of reading is to construct for yourself a refuge from almost all the miseries of life.

A.his

B.its

C.it

D.him

题型:单项选择题

每个机翼中装有两个电动传输活门,其作用是()

A.将燃油从外侧油箱传输到内侧油箱

B.将将燃油从中央油箱传输到内侧油箱,再供给发动机

C.将燃油从内侧油箱传输到外侧油箱,以克服机翼弯曲并减轻颤振

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