多项选择题

6.5.1# 下列关于分程控制方案的描述中，正确的有（  ）。 A.
分程控制是通过阀门定位器或电-气阀门定位器来实现的；
B.
阀门定位器将调节器输出的压力信号分成几段；
C.
各分段压力信号由相应的阀门定位器转化为20~100kPa压力信号，进而使每个调节阀都能全行程动作；
D.
各分段的调节阀不都能全行程动作。

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听力原文： Last summer I was working in Washington, D.C., as an intern at the Armed Forces Institute of Pathology. In one way it was an awful job because the purpose was to figure out ways to identify dead people, like identifying the remains of soldiers in wars, or bodies after disasters such as plane crashes or earthquakes. But the exciting part was that I was working with a scientist who heads a program that is identifying bodies by their DNA structures. As you know, DNA is the name for the genetic material in our bodies. In the past, all soldiers had to wear a necklace and a metal tag with their names and identification numbers on the tag. But this method of identification was not very accurate because the tags could be lost or switched arounD.So in my job I worked at helping the Institute to set up a DNA file to store the genetic information for new soldiers. The armed forces will get a blood sample from each person in the military. Then, if the body of a military person cannot be identified by its tag, fingerprints, or dental records, the body tissue can be analyzed and matched with DNA records at the InstitutE.(23)A.To prevent disease among military personnel.B.To investigate serious crimes in the military.C.To find ways of identifying bodies of soldiers.D.To store old military journals and diaries.
A.,
B.
(23)
A.To
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B.To
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C.To
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D.To
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听力原文： In America, where labor costs are so high, 'do it yourself' is a way of lifE.May people repair their own cars, build their own garages, even rebuild their own houses. Soon many of them will also be writing their own books. In Hollywood there is a company that publishes children's books with the help of computers. Although other book companies also publish that way, this company is not like the others. It allows the reader to become the leading character in the stories with the help of computers. Here is how they do it. Let us suppose the child is named Jenny. She lives in New York, and has a dog named Hody. The computer uses this information to make up a story with pictures. The story is then printed up. A child who receives such a book might say, 'This book is about me,' so the company calls itself the 'Me- books Publishing Company.'Children like the me-books because they like to see their own names in print and the names of their friends and their pets. But more important, in this way, readers are much more interested in reading the stories. Me-books are helping a child to learn how to reaD.(26)A.They can do better than others.B.It is expensive to hire labor.C.They don't like to be helpeD.D.They don't trust others.
A.'
B.
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D.They
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