With the explosive increase of the network information,people can find information more and more difficultly. The occurrence of the Web search engine overcomes this problem in some degree. This paper tells about the h...With the explosive increase of the network information,people can find information more and more difficultly. The occurrence of the Web search engine overcomes this problem in some degree. This paper tells about the history of the search engine ,the current state of the search engine. Some guidelines about the search engine are analysed and the related checking methods are also given. In this basis, we introduce the trend of the search engine.展开更多
The convergence properties of the Fletcher-Reeves method for unconstrained optimization are further studied with the technique of generalized line search. Two conditions are given which guarantee the global convergenc...The convergence properties of the Fletcher-Reeves method for unconstrained optimization are further studied with the technique of generalized line search. Two conditions are given which guarantee the global convergence of the Fletcher-Reeves method using generalized Wolfe line searches or generalized Arjimo line searches, whereas an example is constructed showing that the conditions cannot be relaxed in certain senses.展开更多
文摘With the explosive increase of the network information,people can find information more and more difficultly. The occurrence of the Web search engine overcomes this problem in some degree. This paper tells about the history of the search engine ,the current state of the search engine. Some guidelines about the search engine are analysed and the related checking methods are also given. In this basis, we introduce the trend of the search engine.
基金Project supported by the National Natural Science Foundation of China (Grant No. 19801033).
文摘The convergence properties of the Fletcher-Reeves method for unconstrained optimization are further studied with the technique of generalized line search. Two conditions are given which guarantee the global convergence of the Fletcher-Reeves method using generalized Wolfe line searches or generalized Arjimo line searches, whereas an example is constructed showing that the conditions cannot be relaxed in certain senses.