[国际新闻] 国际象棋电脑程序堪称无敌

中新网7月21日电加拿大一组科学家用18年的时间，开发了堪称无敌的国际象棋(checkers)电脑程序——契努克(Chinook)。该组科学家宣称，没有人能够打败它；哪怕对手一步也不出错，顶多也只是取得和局。% S1 ^5 a# t; b+ } h: G
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加拿大艾伯塔大学电脑系系主任谢弗教授和他领导的电脑高手研究团队研发了契努克。他们在这18年时间内，研究国际象棋的各种走法，总共计算了5000亿步棋。

　　谢弗表示，他最初的目标是希望打败世界冠军。1990年，契努克进入世界大赛；1992年，打入决赛却最终折翼；直到1994年，才成为第一个获得世界冠军殊荣的电脑棋手。

　　2001年，谢弗团队再次着手修改优化程序；今年4月，这一国际象棋大王终于诞生。
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　　谢弗教授团队的这项成就就刊登在前天出版的《科学》期刊内。契努克的诞生提升了人工智能的成就，提高了电脑的运算和记忆功能，是这一科学领域的重要里程碑。

Breakthrough in artificial intelligence as computer wins at draughts% }( {) P- Q% ^8 r: M

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After 18 years of practice, computers have finally conquered the game of draughts人在德国社区+ r- s- [( P7 m+ @, e7 k$ y2 C

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Draughts, known as checkers in America, is a popular board game with a history that dates back 5,000 years. 人在德国社区9 J; ~+ l/ F; U. \! p
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Disc-shaped counters move diagonally on a chequered board one square at a time and jump over an opponent's pieces to capture them. Counters that reach an opponent's end of the board are crowned "kings" and can then move backwards as well as forwards.

The game is essentially simple, but working out responses to every possible move meant sifting through 500 billion billion (five followed by 20 zeroes) different play positions. 2 S5 V* D" q6 G% R8 j1 X4 ^+ m( L

An average of 50 computers were run together every day for years at a time to complete the programme, known as Chinook. At peak periods, more than 200 computers were in use. 5 k/ ?* y/ J- u
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Scientists led by Dr Jonathan Schaeffer, from the University of Alberta in Edmonton, Canada, sought the help of top-level draughts players to programme the computers.
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Chinook now contains all the information needed to predict the best move to play in every situation of a game. Even making no mistakes, the best an opponent taking on the programme could achieve would be a draw. # C0 J6 z4 P1 Q. |) {

Dr Schaeffer, whose team describe the programme in the journal Science, said: "I think we've raised the bar - and raised it quite a bit - in terms of what can be achieved in computer technology and artificial intelligence. With Chinook, we've pushed the envelope about one million times more than anything that's been done before. 5 k+ M8 Y4 g8 `
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"We've taken the knowledge used in artificial intelligence applications to the extreme by replacing human-understandable heuristics (rules of thumb) with perfect knowledge. It's an exciting demonstration of the possibilities that software and hardware are now capable of achieving."
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Dr Schaeffer, who chairs the University of Alberta's Department of Computing Science, started the Chinook project in 1989, with a view to winning the human world checkers championship. ! e1 ]6 F) Q( |) Q3 P4 W
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Chinook lost the championship match in 1992, but won two years later, becoming the first computer programme to win a human world championship in any game - a feat recognised by the Guinness Book of World Records. 5 S% G& f3 Y; N% }: a5 ?

The programme remained undefeated until it was "retired" in 1997. Dr Schaeffer re-started the project in 2001, now with the goal of developing a "perfect" draughts programme. % z5 y/ M4 _! C4 N
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"Solving checkers has been something of an obsession of mine for nearly two decades, and it's really satisfying to see it through to its conclusion," he said. rs238848.rs.hosteurope.de0 Y$ m& K$ Q4 u" |
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Dr Jaap van den Herik, editor of the International Computer Games Journal, said: "This is a tremendous achievement - a truly significant advance in artificial intelligence." 7 A. r0 Q" i3 K5 |6 Q

Although computers can play a good game of chess, creating an unbeatable chess programme is still out of the question using current technology. The game is simply too complex, with a much larger "search space" containing all possible moves than in draughts.
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However the Alberta team has developed Polaris, a poker-playing computer programme.

Next week Polaris will challenge poker professionals in a £24,000 man-versus-machine world championship in Vancouver. The event is part of the annual conference of the Association for the Advancement of Artificial Intelligence, being held in the Canadian city.人在德国社区% s6 u; ~8 k8 t* h" a
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[ 本帖最后由日月光于 2007-7-21 20:23 编辑 ]