لینک دانلود و خرید پایین توضیحات
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نوع فایل : .ppt ( قابل ویرایش و آماده پرینت )
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قسمتی از متن .ppt :
1/19
Informed search algorithms
Chapter 4
Modified by Vali Derhami
2/19
Relaxed problemsمسائل تعدیل شده
A problem with fewer restrictions on the actions is called a relaxed problem
The cost of an optimal solution to a relaxed problem is an admissible heuristic for the original problem
If the rules of the 8-puzzle are relaxed so that a tile can move anywhere, then h1(n) gives the shortest solution
If the rules are relaxed so that a tile can move to any adjacent square, then h2(n) gives the shortest solution
ترکیب هیوریستیک ها: h(n)=max(h1(n), h2(n), .. hm(n))
اگر همه hiها قابل قبول باشند h(n) هم قابل قبول و اگر همه سازگار باشند h(n) هم سازگار خواهد بود
3/19
Local search algorithms
In many optimization problems, the path to the goal is irrelevant; the goal state itself is the solution, such as 8 queens problem
State space = set of "complete" configurations
Find configuration satisfying constraints, e.g., n-queens
In such cases, we can use local search algorithms
keep a single "current" state, try to improve it
4/19
Example: n-queens
Put n queens on an n × n board with no two queens on the same row, column, or diagonal