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基于信息离散度的DNA序列相似性分析 被引量:4
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作者 骆嘉伟 刘芳 杨华 《计算机应用》 CSCD 北大核心 2009年第1期269-272,共4页
信息离散性度量方法在生物信息处理领域中获得成功的应用,其基本思想是利用子序列分布差异来表示序列之间的差异,但是子序列长度的变化对结果的影响较大。文中提出了一种新的基于信息离散度的DNA序列相似性分析方法,利用不同距离的碱基... 信息离散性度量方法在生物信息处理领域中获得成功的应用,其基本思想是利用子序列分布差异来表示序列之间的差异,但是子序列长度的变化对结果的影响较大。文中提出了一种新的基于信息离散度的DNA序列相似性分析方法,利用不同距离的碱基对的联合概率分布差异来表示DNA序列之间的差异,并分析了信息集变化对结果的影响。实验结果表明,该方法是分析DNA序列相似性的简单且有效的工具。当信息集变化时,相似度较高的序列间的距离值变化很小。 展开更多
关键词 碱基对 完全信息集 离散度函数 相似性
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氨基酸序列特征提取方法研究 被引量:3
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作者 罗林波 陈绮 《计算机技术与发展》 2010年第2期206-208,212,共4页
组成蛋白质的基本单位是氨基酸,对于蛋白质分类预测问题,氨基酸序列特征提取方法是一个非常重要的因素。对基于氨基酸组成、位置的特征提取算法如熵密度、n阶耦联组成和基于氨基酸性质的特征提取方法如自相关函数、伪氨基酸组成等方法... 组成蛋白质的基本单位是氨基酸,对于蛋白质分类预测问题,氨基酸序列特征提取方法是一个非常重要的因素。对基于氨基酸组成、位置的特征提取算法如熵密度、n阶耦联组成和基于氨基酸性质的特征提取方法如自相关函数、伪氨基酸组成等方法进行了阐述,并进行了简单评价。基于氨基酸组成的方法实现简单、计算量小,且对所有的氨基酸序列都适用,但丢失了氨基酸的顺序信息以及其间的相互作用,基于氨基酸位置信息或理化特性等方法计算量非常大,科研工作者可以根据对蛋白质的不同要求选择相应的特征提取方法。 展开更多
关键词 特征提取 熵密度 完全信息集
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A Decision Model Based on Grey Rough Sets Integration with Incomplete Information 被引量:5
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作者 HOU Ya-lin LUO Dang 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第1期151-158,共8页
In this paper, for multiple attribute decision-making problem in which attribute values are interval grey numbers and some of them are null values, a decision model based on grey rough sets integration with incomplete... In this paper, for multiple attribute decision-making problem in which attribute values are interval grey numbers and some of them are null values, a decision model based on grey rough sets integration with incomplete information is proposed. We put forward incidence degree coefficient formula for grey interval, by information entropy theory and analysis technique, the method and principle is presented to fill up null values. We also establish the method of grey interval incidence cluster. Because grey system theory and Rough set theory are complementary each other, decision table with preference information is obtained by the result of grey incidence cluster. An algorithm for inducing decision rules based on rough set theory and the dominance relationship is presented. In some extent, this algorithm can deal with decision-making problem in which the attribute values are interval grey numbers and some of them are null values. Contrasted with classical model of cluster decision-making, the algorithm has an advantage of flexibility and compatibility to new information. 展开更多
关键词 grey system theory rough set incidence cluster interval grey number entropy null value
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Extension of information entropy-based measures in incomplete information systems
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作者 李仁璞 黄道 高茂庭 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第5期544-550,共7页
It is helpful for people to understand the essence of rough set theory to study the concepts and operations of rough set theory from its information view. In this paper we address knowledge expression and knowledge re... It is helpful for people to understand the essence of rough set theory to study the concepts and operations of rough set theory from its information view. In this paper we address knowledge expression and knowledge reduction in incomplete infolvnation systems from the information view of rough set theory. First, by extending information entropy-based measures in complete information systems, two new measures of incomplete entropy and incomplete conditional entropy are presented for incomplete information systems. And then, based on these measures the problem of knowledge reduction in incomplete information systems is analyzed and the reduct definitions in incomplete information system and incomplete decision table are proposed respectively. Finally, the reduct definitions based on incomplete entropy and the reduct definitions based on similarity relation are compared. Two equivalent relationships between them are proved by theorems and an in equivalent relationship between them is illustrated by an example. The work of this paper extends the research of rough set theory from information view to incomplete information systems and establishes the theoretical basis for seeking efficient algorithm of knowledge acquisition in incomplete information systems. 展开更多
关键词 rough set theory information entropy incomplete information system knowledge reduction
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