Inside the computer, the operation system (of another software module called a data communication (71) )must decide which program will get control next. Each program remember, is associated (72) . a particular front -end port. If a program’s data have not yet reached its front - end buffer, there is no point giving that program control. Thus the data communication monitor sends its own (73) signal to the front -end devices next port is polled. Note that the (74) computer speed. The computer never has to wait for a terminal or a communication line. Instead, it is the expressive front - end processor that waits for the slower system (75) to respond.
（74）处填（）。Inside the computer, the operation system (of another software module called a data communication (71) )must decide which program will get control next. Each program remember, is associated (72) . a particular front -end port. If a program’s data have not yet reached its front - end buffer, there is no point giving that program control. Thus the data communication monitor sends its own (73) signal to the front -end devices next port is polled. Note that the (74) computer speed. The computer never has to wait for a terminal or a communication line. Instead, it is the expressive front - end processor that waits for the slower system (75) to respond.
（71）处填（）。
Passage Two Clifford Stoll ran a computer system in Berkeley, California. As a system administrator, he kept a close eye on the records. One day, Stoll found something strange in the payment record. There was a 75 cents mistake. One of the thousands of users had used the system for 75 cents worth of time and not paid for it. It might sound like very little money to worry about. But that 75 cents was the first clue Stoll had to a much bigger problem--that a hacker had broken into Stoll’ s computer system. Who was it Stoll spent the next year trying to find out. During that time the hacker used the system in Berkeley as a starting point to break into military computer systems all over the United States. Stoll had to keep track of the hacker’s activities on the computer without the hacker’ s knowing someone was watching him. Stoll even made up huge files of false information so the hacker would have lots to read. When the hacker spent long time reading, the
A. student
B. hacker
C. manager
D. professor
| A new computer system has been designed to stop
ships sinking. The greatest danger{{U}} (21) {{/U}}a holed vessel is
that flooding of its compartments will make the ship unstable enough to capsize.
It is estimated that nearly half the ships{{U}} (22) {{/U}}during the
second world war capsized because of the loss of{{U}} (23)
{{/U}}. Pacer systems of Burlington, Massachusetts, has now{{U}} (24) {{/U}}a system devised by a{{U}} (25) {{/U}}US Navy officer, Stephen Drabouski, which effectively thought out alternative strategies for the ship. The{{U}} (26) {{/U}}is programmed with every possible eventuality of flood damage.{{U}} (27) {{/U}}the actual damage is keyed into the computer the operator is told by the computer{{U}} (28) {{/U}}the implications are and what can be done to destabilize the vessel. Trials on the "America A. after B. before C. provided D. now that 我来回答: 提交
|
