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The Structure Entropy of Social Networks

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Journal of Systems Science & Complexity 2024年第3期37卷 1147-1162页

作者： LI Zhenpeng yan zhihua yanG Jian TANG Xijin School of Electronics and Information Engineering Taizhou UniversityLinhai 317000China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Yunnan Key Laboratory of Smart City in Cyberspace Security Yuxi Normal UniversityYuci 653100China University of Chinese Academy of Sciences Beijing 100039China

Micro triadic structure is an important motif and serves the building block of complex *** this paper,the authors define structure entropy for a social network and explain this concept by using the coded triads proposed by Davis and Leinhardt in *** proposed structure entropy serves as a new macro-evolution index to measure the network’s stability at a given *** analysis of real-world network structure entropy discloses rich information on the mechanism that yields given triadic motifs frequency *** paper illustrates the intrinsic link between the micro dyadic/triadic motifs and network structure ***,the authors find that the high proportion of reciprocity and transitivity results in the emergence of hierarchy,order,and cooperation of online social networks.

关键词： Dyadic and triadic motifs network structure entropy reciprocity and transitivity

Exploring Evolution of Public Opinions on Tianya Club Using Dynamic Topic Models

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Journal of Systems Science and Information 2020年第4期11卷 309-324页

作者： zhihua yan Xijin TANG Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Online media have brought tremendous changes to civic life, public opinions, and government administration. Compared with traditional media, online media not only allow individuals to browse news and express their views more freely, but also accelerate the transmission of opinions and expand influence. As public opinions may arouse societal unrest, it is worth detecting the primary topics and uncovering the evolution trends of public opinions for societal administration. Various algorithms are developed to deal with the huge volume of unstructured online media data. In this study,dynamic topic model is employed to explore topic content evolution and prevalence evolution using the original posts published from 2013 to 2017 on the Tianya Zatan Board of Tianya Club, which is one of the most popular BBS in China. Based on semantic similarities, topics are grouped into three themes: Family life, societal affairs, and government administration. The evolution of topic prevalence and content are affected by emergent incidents. Topics on family life become popular, while themes"societal affairs" and "government administration" with bigger standard deviations are more likely to be influenced by emergent hot events. Content evolution represented by monthly pairwise distance matrix is very easy to find change points of topic content.

关键词： likely administration Topic

Uniqueness Theorem of Meromorphic Mappings with Moving Targets

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Chinese Annals of Mathematics,Series B 2006年第4期27卷 393-400页

作者： zhihua CHEN Qiming yan Department of Mathematics Tongji University Shanghai 200092 China.

Some uniqueness theorems of meromorphic mappings with moving targets are given under the inclusion relations between the zeros sets of meromorphic mappings.

关键词： Uniqueness theorem Meromorphic mapping Moving hyperplane

@AMORPHOUS Ni50Ti50 FILM FORMED BY SOLID-STATE REACTION

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Chinese Physics Letters 1987年第12期4卷 569-571页

作者： yan zhihua WANG Wenkui Institute of Physics Academy SinicaBeijing

The solid-state reaction technique has been used to form the amorphous Ni_(50)Ti_(50) *** alternative layers were prepared by an electron beam evaporating *** amorphization was determined by means of X-ray diffraction... 详细信息

关键词： amorphization apparatus amorphous

SOLED STATE AMORPHIZATION REACTION REACTION UNDER HIGH PRESSURE

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Chinese Physics Letters 1989年第4期6卷 173-176页

作者： yan zhihua LI Jinfeng WANG Wenkui Institute of Physics Academia SinicaBeijing Depax tment of Mat erial Science Jilin UniversityJilin

The solid state reaction of Nigo Tigo multilayer under high pressure was carried out to investigate the effect of pressure on the amorphization *** the pressure of BOkbars amorphization reaction could not occur at 250℃while amorphous phase formed by isothermal annealing at same temperature in vacuum as well as lower *** is suggested that the effect of pressure on diffusion played a predominant role,and Ni atom should diffuse into Ti layers with vacancy mechanism rather than interstitial one.

关键词： process annealing amorphous

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融合高效用模式的在线媒体突发话题发现

系统工程理论与实践 2021年第5期41卷 1138-1149页

作者：闫志华唐锡晋中国科学院数学与系统科学研究院北京100190 中国科学院大学北京100049

在线媒体拥有海量的非结构化数据,包含大量的突发话题和普通话题.传统的话题模型在不加入先验信息的情况下,无法有效区分普通话题和突发话题.本文的研究提出基于高效用模式和话题模型的突发话题发现(high utility bursty topic model,HU... 详细信息

在线媒体拥有海量的非结构化数据,包含大量的突发话题和普通话题.传统的话题模型在不加入先验信息的情况下,无法有效区分普通话题和突发话题.本文的研究提出基于高效用模式和话题模型的突发话题发现(high utility bursty topic model,HU-BTM)模型.该模型使用高效用模式挖掘找出文本数据中的突发词组,使用基于普通Polya坛子模型的Gibbs抽样方法,将突发词组与突发词引入话题模型,实现突发话题的自动识别.实验结果表明与现有的主要突发话题发现方法比较,HU-BTM模型在准确率和召回率指标上优于对比算法.

关键词：高效用模式突发话题发现话题模型在线媒体

UNIQUENESS PROBLEM WITH TRUNCATED MULTIPLICITIES OF MEROMORPHIC MAPPINGS FOR MOVING TARGETS

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Acta Mathematica Scientia 2007年第3期27卷 625-634页

作者：陈志华李燕华颜启明 Department of Mathematics Tongji University

In this article, two uniqueness theorems of meromorphic mappings on moving targets with truncated multiplicities are proved.

关键词： Moving targets uniqueness theorem value distribution

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中低速磁浮线连续弯梁设计研究

城市轨道交通研究 2010年第4期13卷 54-57页

作者：颜志华铁道第三勘察设计院集团有限公司天津工程师300142

依托唐山试验线曲线半径为100m的17.7m+27m+17.7m斜弯连续梁,对中低速磁浮线轨道梁设计进行初步探讨。为了满足车辆限界和轨道安装及承轨台预埋件的要求,连续曲梁截面斜置,构成复杂的空间扭转曲线箱梁。轨道梁桥面与轨道采用承轨台上置... 详细信息

依托唐山试验线曲线半径为100m的17.7m+27m+17.7m斜弯连续梁,对中低速磁浮线轨道梁设计进行初步探讨。为了满足车辆限界和轨道安装及承轨台预埋件的要求,连续曲梁截面斜置,构成复杂的空间扭转曲线箱梁。轨道梁桥面与轨道采用承轨台上置式连接方式。为了增加轨道梁的横向稳定性,采取了增大梁宽、加大支座横向间距、设置拉力支座等构造措施。根据连续曲梁的受力特点,建立空间模型进行了计算分析,并参考相关规范,讨论了轨道梁刚度和动力特性的设计要求。

关键词：中低速磁浮连续梁设计

基于演化博弈的药品质量安全监管“人理”分析

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管理评论 2021年第5期33卷 64-75页

作者：闫志华唐锡晋中国科学院数学与系统科学研究院北京100190 中国科学院大学北京100049

药品质量安全监管涉及众多利益相关者,是一个复杂的系统问题。本文应用物理-事理-人理方法论(Wuli-Shili-Renli System Approach,WSR)探讨药品质量安全监管中的物理、事理、人理,提出药品质量安全监管的WSR框架。以往WSR方法论研究中"人... 详细信息

药品质量安全监管涉及众多利益相关者,是一个复杂的系统问题。本文应用物理-事理-人理方法论(Wuli-Shili-Renli System Approach,WSR)探讨药品质量安全监管中的物理、事理、人理,提出药品质量安全监管的WSR框架。以往WSR方法论研究中"人理"分析以描述性讨论为主,本文使用演化博弈方法对药品质量安全监管中的参与主体的行为和利益动机进行建模,探讨了参与主体的行为影响要素,为药品质量安全监管机制的设计提供依据。在此基础上,研究以长生生物疫苗造假事件为例,分析长生生物、监管机构、地方政府等的行为策略,阐明药品质量安全监管中人理对药品质量监管的重要意义。研究结果表明:基于WSR的药品质量安全监管方案需要综合考虑社会舆情、监管力度和问责力度;不断完善现有监管机构管理模式,可以规避监管机构的机会主义;社会公众通过产生社会舆情表达诉求可能会使药品质量监管陷入震荡状态。

关键词：药品质量安全监管 WSR系统方法论人理演化博弈论