The Turing machine is an abstract (71) of computer execution and storage introduced in 1936 by Alan Turing to give a mathematically precise definition of (72) . or ’mechanical procedure’. As such it is still widely used in theoretical computer science, especially in (73) theory and the theory of computation. The thesis that states that Turing machines indeed capture the informal notion of effective or mechanical method in logic and mathematics is known as Turing’s thesis.
B.
Every Turing machine computes a certain (74) partial function over the strings over its alphabet. In that sense it behaves like a computer with a fixed program. However, as Alan luring already described, we can encode the action table of every Turing machine in a string. Thus we might try to construct a Turing machine that expects on its tape a string describing an action table followed by a string describing the input tape, and then computes the tape that the encoded Turing machine would have computed. As Turing showed, such a luring machine is indeed possible and since it is able to simulate any other Turing machine it is called a (75) Turing machine.
C.
A universal Turing machine is Turing complete. It can calculate any recursive function, decide any recursive language, and accept any recursively enumerable language. According to the Church-Turing thesis, the problems solvable by a universal Turing machine are exactly those problems solvable by an algorithm or an effective method of computation, for any reasonable definition of those terms.
You want to use the Web to let Eternal users or your customers look at corporate information. But you want to keep installation at the user end (66) and you don’t want just anyone to get (67) your databases.
B.
That may be where an application server enters the picture. For more user machine independent, these t software packages, typically written in the (68) programming language.
C.
for use on Windows NT-based systems, act as go-betweens linking browser-equipped end users to the databases that (69) the information they need to (70) 。
Like many other aspects of the computer age, Yahoo began as an idea, (1) into a hobby and lately has (2) into a full-time passion. The two developers of Yahoo, David Filo and Jerry Yang, Ph.D. candidates (3) Electrical Engineering at Stanford University, started their guide in April 1994 as a way to keep (4) of their personal interest on the Internet. Before long they (5) that their homebrewed lists were becoming too long and (6) Gradually they began to spend more and more time on Yahoo.
B.
During 1994, they (7) yahoo into a customized database designed to (8) the needs of the thousands of users (9) began to use the service through the closely (10) Internet community. They developed customized software to help them efficiently locate, identify and edit material stored on the Internet.
When the subject is money, women often cling to two persistent stereotypes, one a pleasant dream, the other a nightmare.
B.
In the (1) , they hate fantasies that a white (2) will provide happily-ever-after financial security. (3) the nightmare, by contrast, they fear that an impoverished retirement could (4) them into bag ladies on the street.
C.
Now (5) advisers and managers are (6) forces to change those images. In a proliferation of books, seminars, conferences, Web (7) , and investment clubs, they are (8) out to women, helping them to become financially savvy and economically (9) . Prince Charming, they warn, may not come.
D.
"If and when he does show (10) , he may have less than you do," quips Brooke Stephens, a financial adviser.