问题 判断题

闭环控制系统可以抑制闭环内的一切干扰,但往往对时间常数大的被控对象反应慢。开环控制系统在按干扰控制时,由于没有被控量反馈,因此不能最后检查被控量是否等于给定值。

答案

参考答案:

问答题

打开考生文件夹下的Word文档WORD1.doc,其内容如下:
[WORD1.doc文档开始]
最低生活保障标准再次调高
本报讯经北京市政府批准,本市城市居民最低生活保障标准再次调整,由家庭月人均收入280元增加到285元。新标准的执行起始日期定为今年7月1日。
据了解,1996年7月1日本市开始建立城市居民最低生活保障制度时,最低生活保障标准为家庭月人均收入170元,到目前为止已经调整过6次,累计投入救助资金近3.9亿元。
又讯本市将对最低工资标准、下岗职工基本生活费标准进行调整,最低工资标准从每月412元调整到435元,下岗职工的基本生活费从每人每月296元调整到305元。最低工资标准从每小时不低于2.46元人民币,提高到每小时不低于2.6元人民币。该通知从2001年7月1日起执行。
[WORD1.doc:文档结束]
按要求对文档进行编辑、排版和保存。
(1) 将文中所有“最低生活保障标准”替换为“低保标准”;将标题段(“低保标准再次调高”)设置为三号楷体_GB2312、居中、字符间距加宽3磅、并添加蓝色阴影边框。
(2) 将正文各段文字(“本报讯……从2001年7月1日起执行。”)设置为五号宋体;首行缩进2字符、段前间距0.5行;正文中“本报讯”和“又讯”二词设置为五号黑体。
(3) 将正文第三段(“又讯……从2001年7月1日起执行。”)分为等宽的两栏、栏间距为1字符、栏间加分隔。

阅读理解

What do you do if you are hit in the mouth and one of your teeth is knocked out? A dentist(牙医)may be able to put the tooth back in for you, but you have to get to the dentist first.In the meantime, you have to store the tooth so that it will stay healthy.

The simplest thing to do is put the tooth back into your mouth, or you could put it in milk.Frank Courts, a dentist at the University of Florida, worked with other researchers to find the safest way of keeping knocked-out teeth.He tried putting teeth into milk, into water, and into cell-culture medium(细胞培养液).He also tried, just drying the teeth in the open air.He used teeth that had to be removed from people’s mouths for various reasons.The teeth were put into one of the solutions(溶液)or stored in the air for one hour.Then cells from the root of the teeth were scraped-off the teeth.Dr.Courts and the others then studied how healthy these cells were.

The cell-culture medium worked best to keep a knocked-out tooth healthy outside the mouth.However, few people keep cell-culture medium handy at home or in school.

The next best thing was milk.But Dr.Courts said that the best thing of all was to wash the tooth and put it right back into its socket(牙槽)in the mouth.For some people, though, this is just too painful or upsetting.So milk will do, until you get your tooth (and your mouth)to a dentist.

小题1:This passage is mainly about             .

A.how a dentist can save a knocked-out tooth

B.how to keep a knocked-out tooth healthy

C.how Dr.Courts and other researchers made their experiments

D.how to put a knocked-out tooth back into its socket小题2:The best way to keep a knocked-out tooth healthy outside the mouth is to store it       .

A.in cell-culture medium

B.in milk

C.in water

D.in the open air小题3:Milk can be used instead of cell-culture medium to put a knocked-out tooth in because    .

A.milk works better to keep the tooth healthy

B.milk causes less pain

C.cell-culture medium is not usually handy

D.cell-culture medium is more expensive小题4:“Dr.Courts said that the best of al1 was to wash the tooth and put it right back into its socket in the mouth.”In the sentence, the word “best” means              .

A.cheapest and healthiest

B.least painful and cheapest

C.quickest and least painful

D.easiest and healthiest