根据服务对象不同，常用的单处理机OS可以分为如下三种类型：允许多个用户在他们所在的终端上同时交互地使用计算机的OS称之为分时OS，它通常采用策略为用户服务；允许用户把若干个作业提交计算机集中处理的OS，称为______，衡量这种系统性能的一个主要指标是系统的吞吐率；在______的控制下，计算机系统能及时处理由过程控制反馈的数据并做出响应。设计这种系统时，应首先考虑系统的实时性和可靠性。
参考答案：时间片轮转；批处理OS；实时OS
| 阅读理解。 |
| "Time is a problem for children," says a news report for a new Swiss watch. Children in some countries "learn time slowly" because "they don't wear watches" and "parents don't really know how to teach them time." The children grow up with this handicap and become adults and then can't get to work on time. Is there an answer to this problem? Of course it's the Flik Flak, made by a famous Swiss watch company. The Flik Flak is being marketed as something teaching watch for children aged 4 to 10. The watch itself does not teach children how to tell time, of course; it only "takes their imagination" by presenting the "hour" hand as a beautiful red girl named Flak and the "minute" hand as a tall blue boy named Flik. Flik points to "blue" minutes on the dial (钟面), while Flak points to "red" hour numbers. The characters and colors together with parental help, are supposed to teach young children how to tell time. Peter Lipkin, the United States sales manager for the Flik Flak, calls it "childproof: if it gets dirty you can throw the whole watch in the washing machine," The product is being sold in some department stores in Europe, Asia and the United Stares for a suggested price of $25. Parents who buy the watch may find that it is odd thing to tell time; it's quite another for them to be on time. |
| 1．From the news report we know that _______. |
[ ] |
| A．parents are patient when they are teaching children time B．parents have little idea of how to teach children time C．children in every country learn time slowly D．children enjoy wearing the Flik Flak watch |
| 2．The underlined word "handicap" in the first paragraph means _______. |
[ ] |
| A．优势 B．特点 C．失望 D．不足 |
| 3．The United State sales manager calls the new watch "childproof" because _______. |
[ ] |
| A．it is designed to teach children to be on time B．it proves to be useful in teaching children time C．it is made so as not to be easily broken by children D．it is the children's favorite watch |