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编码混淆:一种新型匿名通信模型

武汉大学学报（理学版） 2011年第5期57卷 401-407页

作者：吴振强马亚蕾陕西师范大学计算机科学学院陕西西安710062

无线网络的特殊性决定了它会受到多种网络攻击的威胁,目前的广播、代理、洋葱路由和包混淆等匿名通信模型都无法完全适应链路开放、拓扑结构动态变化、资源有限的无线网络.本文在比较分析了抗流量分析的匿名技术基础上,根据网络编码具... 详细信息

无线网络的特殊性决定了它会受到多种网络攻击的威胁,目前的广播、代理、洋葱路由和包混淆等匿名通信模型都无法完全适应链路开放、拓扑结构动态变化、资源有限的无线网络.本文在比较分析了抗流量分析的匿名技术基础上,根据网络编码具有混淆与伪装数据的功能,提出了一种新型编码混淆匿名通信模型.该模型通过链路层编码混淆、网络层数据包拆分与多径路由等方法相结合,使路由节点数据包出入的对应关系和信息表现形式发生变化,提高匿名通信的抗攻击能力;新模型可以实现通信的保密性与匿名性.

关键词：编码混淆网络编码多径路由匿名通信基础设施

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求解TSP的改进自组织PSO算法

计算机工程与应用 2009年第31期45卷 30-33页

作者：孙晶晶雷秀娟陕西师范大学计算机科学学院西安710062

针对粒子群算法(PSO)的早熟收敛现象,从种群多样性出发,基于自组织临界性特点改进PSO算法的参数设置,采用自组织的惯性权重和加速系数,并增加了变异算子。借鉴交换子和交换序概念,设计出了能直接在离散域进行搜索的改进的自组织PSO算法... 详细信息

针对粒子群算法(PSO)的早熟收敛现象,从种群多样性出发,基于自组织临界性特点改进PSO算法的参数设置,采用自组织的惯性权重和加速系数,并增加了变异算子。借鉴交换子和交换序概念,设计出了能直接在离散域进行搜索的改进的自组织PSO算法。用于旅行商问题(TSP)的求解,并与基本及其他典型改进PSO算法进行性能比较。实验结果证实改进的自组织PSO算法是有效的。

关键词：粒子群算法自组织种群多样性旅行商问题(TSP)

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空间信息网抗毁安全路由协议

武汉大学学报（理学版） 2011年第5期57卷 413-418页

作者：郝选文马建峰刘小跃西安电子科技大学计算机网络与信息安全教育部重点实验室陕西西安710071 陕西师范大学计算机科学学院陕西西安710062

对空间信息网路由协议进行了研究,提出了一种基于GEO-LEO(geosynchronous earth orbit,GEO;low earth orbit,LEO)双层卫星组网的空间信息网抗毁安全路由协议.协议中GEO卫星组提供对LEO卫星的分组管理、密钥管理和超远距离中继服务功能,... 详细信息

对空间信息网路由协议进行了研究,提出了一种基于GEO-LEO(geosynchronous earth orbit,GEO;low earth orbit,LEO)双层卫星组网的空间信息网抗毁安全路由协议.协议中GEO卫星组提供对LEO卫星的分组管理、密钥管理和超远距离中继服务功能,LEO卫星担任主要通信任务,路由消息采用对称密钥加密;协议在每个卫星周期时间片起始路由查找产生路由表并对该路由表进行存储,若在该卫星周期内没有卫星节点失效或链路拥塞的情况出现,路由表保持不变,否则触发路由更新过程.仿真分析实验表明,该抗毁安全路由协议在信令开销不大的情况下对空间信息网路由消息的可靠性和安全性有很大提高.

关键词：空间信息网卫星抗毁安全路由

Finite automata based on quantum logic and monadic second-order quantum logic

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science China(Information sciences) 2010年第1期53卷 101-114页

作者： LI YongMing College of computer science, shaanxi normal university, Xi’an 710062, China College of computer science Shaanxi Normal University Xi’an China

We introduce monadic second-order quantum logic and prove that the behaviors of finite automata based on quantum logic are precisely the quantum languages definable with sentences of our monadic secondorder quantum logic. This generalizes Büchi’s and Elgot’s fundamental theorems to quantum logic setting. We also consider first-order quantum logic and show that star-free quantum languages and aperiodic quantum languages introduced here coincide with the first-order quantum definable ones. This generalizes Schützenberger’s fundamental theorems to quantum logic setting. The determinazation of finite automata based on quantum logic is studied by introducing the generalized subset construction method. Then the Kleene theorem in the frame of quantum logic is presented here.

关键词： quantum logic finite automaton monadic second quantum logic quantum language quantum computation Kleene theorem

Characterizations of α-Bloch functions on the unit ball without use of derivative

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science China Mathematics 2008年第11期51卷 1965-1981页

作者： CHEN HuaiHui school of Mathematics and computer science, Nanjing normal university, Nanjing 210097, China school of Mathematics and computer science Nanjing Normal University Nanjing China

In this paper we establish characterizations of α-Bloch functions on the unit ball without use of derivative, which are stronger, more precise and general than those obtained by Nowak and Zhao.

关键词： α-Bloch function unit ball Bergman metric

Progress in the studies of low-molecular mass gelators with unusual properties

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science China Chemistry 2011年第4期54卷 575-586页

作者： LIU KaiQiang,HE PanLi & FANG Yu Key Laboratory of Applied Surface and Colloid Chemistry (shaanxi normal university),Ministry of Education school of Chemistry and Materials science,shaanxi normal university,Xi’an 710062,China Key Laboratory of Applied Surface and Colloid Chemistry (shaanxi normal university) Ministry of Education school of Chemistry and Materials science Shaanxi Normal University Xi’an China

This article is intended to provide an overview of recent progress in the studies of cholesterol-based low-molecular mass gelators (LMMGs) with unusual properties,in particular,gelation and selective gelation at room temperature,gel emulsions and gel film formation,*** applications of the LMMGs in spilled oil collection and water purification are briefly presented.

关键词：低分子量凝胶剂性质胆固醇净化水成膜

Progress in the studies of electrochemically controllable host-guest interactions

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Progress in Natural science:Materials International 2005年第12期15卷 1057-1065页

作者： LIU Jing,LI Yuangang and FANG Yu school of Chemistry and Materials science,shaanxi normal university,Xi’an 710062,China school of Chemistry and Materials science Shanxi Normal University Xi'an 710062 China

Studies on the electrochemically controllable host-guest interactions have received considerable attention since the middle of the *** this paper,progress in such studies is reviewed according to the types of the hosts,including cyclodextrin,calixarene, cucurbituril,cyclophane,and so *** addition,perspectives for the future development and potential applications of the interactions are discussed.

关键词： host-guest interaction electrochemistry cyclodextrin calixarene cucurbituril cyclophane

Fixed point theorems for better admissible multimaps on Abstract convex spaces

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Applied Mathematics(A Journal of Chinese Universities) 2010年第1期25卷 55-62页

作者： LIU Xue-wen ZHANG Yue TAN Ren-xin school of Mathematics and computer science, Chongqing normal university, Chongqing 400047, China school of Mathematics and computer science Chongqing Normal University Chongqing China

In this paper, a better admissible class B＋ is introduced and a new fixed point theorem for better admissible multimap is proved on abstract convex spaces. As a consequence, we deduce a new fixed point theorem on abs... 详细信息

关键词： Multimap fixed point abstract convex space better admissible class.

Geometric double-entity model for recognizing far-near relations of clusters

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science China(Information sciences) 2011年第10期54卷 2040-2050页

作者： WANG KaiJun ,YAN XuanHui & CHEN LiFei school of Mathematics and computer science,Fujian normal university,Fuzhou 350108,China school of Mathematics and computer science Fujian Normal University Fuzhou China

When solving many practical problems,we not only need sample labels given by a clustering algorithm,but also rely on the recognition of far-near relations of *** the difficult condition of many clusters in a high-dimensional data set,the clustering visualization methods based on dimension reductions usually produce the phenomena,e.g.,some clusters are overlapping,interlacing,or pushed away;as a result,the far-near relations of some clusters are displayed wrongly or cannot be *** existing inter-cluster distance methods cannot determine whether two clusters are far away or *** geometric double-entity model method (GDEM) is proposed to describe far-near relations of clusters,and the methods such as the relative border distance,absolute border distance and region dense degree are designed to measure far-near degrees between *** pays attention to both the absolute distance between nearest sample sets and the dense degrees of border regions of two clusters,and it is able to uncover accurately far-near relations of clusters in a high-dimensional space,especially under the difficult condition mentioned *** experimental results on four real data sets show that the proposed method can effectively recognize far-near relations of clusters,while the conventional methods cannot.

关键词： geometric double-entity model far-near relations of clusters distance between clusters partitional clustering algorithms