Through an analytical explanation of the concept of impact factor and its derivatives presented by the Institute for Scientific Information(ISI)of the United States,and the case study of their limitations in the proce...Through an analytical explanation of the concept of impact factor and its derivatives presented by the Institute for Scientific Information(ISI)of the United States,and the case study of their limitations in the process of academic evaluation,this paper clarifies that impact factor and its derivatives can not directly reflect or reveal the actual impact and quality of journals and the papers published therein.展开更多
针对WPR(Weighted PageRank)算法存在的在网页搜索方面的主题漂移和偏重旧网页的现象,综合网页的主题特征和最近搜索周期网页的被引用频率两个因素,提出了一种改进的算法WTFPR(Weighted Topic Frequency PageRank)。该算法通过内容分析...针对WPR(Weighted PageRank)算法存在的在网页搜索方面的主题漂移和偏重旧网页的现象,综合网页的主题特征和最近搜索周期网页的被引用频率两个因素,提出了一种改进的算法WTFPR(Weighted Topic Frequency PageRank)。该算法通过内容分析,采用改进的TD-IDF算法来解决网页相关性,改善主题漂移现象;通过网页的最近搜索周期的被引用频率来提高那些较新而且价值较高的网页的PR值,从而改善偏重旧网页的现象。仿真结果表明,改进后的算法与WPR算法相比获得了更好的效果。展开更多
文摘Through an analytical explanation of the concept of impact factor and its derivatives presented by the Institute for Scientific Information(ISI)of the United States,and the case study of their limitations in the process of academic evaluation,this paper clarifies that impact factor and its derivatives can not directly reflect or reveal the actual impact and quality of journals and the papers published therein.
文摘针对WPR(Weighted PageRank)算法存在的在网页搜索方面的主题漂移和偏重旧网页的现象,综合网页的主题特征和最近搜索周期网页的被引用频率两个因素,提出了一种改进的算法WTFPR(Weighted Topic Frequency PageRank)。该算法通过内容分析,采用改进的TD-IDF算法来解决网页相关性,改善主题漂移现象;通过网页的最近搜索周期的被引用频率来提高那些较新而且价值较高的网页的PR值,从而改善偏重旧网页的现象。仿真结果表明,改进后的算法与WPR算法相比获得了更好的效果。
