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A formal model of fair exchange protocols

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Science in china(Series F) 2005年第4期48卷 499-512页

作者： qing sihan1,2.3.& li gaicheng1,2.{2., institute of software, chinese Aca- demy of sciences, beijing 100080, china 2. beijing Zhongke Ansheng Corporation of information technology, beijing 100080, china 3. Graduate School of the chinese academy of sciences, beijing 100039, china engineering research {2. for information security technology Institute of Software Chinese Academy of Sciences Beijing China beijing Zhongke Ansheng Corporation of information {2. Beijing China Graduate School of the chinese academy of sciences Beijing China

Based on the study of existing fair exchange protocols, this paper sets up an accurate formal model by stepwise refinement. In the process of refinement an unreliable channel is employed to simulate an attack behavior. The model provides a novel formal definition of exchanged items, and presents the formal goals for fairness, accountability, etc., reflecting the inherent requirements for fair exchange protocols across-the-board. In order to check, prove, and design fair exchange protocols effectively and efficiently, the model puts forward a novel property of abuse-freeness which applies to all fair exchange protocols, gives a formal definition for trust strand of the third party, and presents general criteria of designing a secure and effective fair exchange protocol. Taking a typical fair exchange protocol as an example, this paper presents the analysis steps of fair exchange protocols appealing to our model. An unknown attack is uncovered. The analysis reveals the process of a complete attack, discovering deeper reasons for causing an attack. Finally, we modify the flawed protocol and the revised protocol ensures the desirable properties.

关键词： events local causal relation local temporal relation global relation exchanged item security goals.

ON DECORRELATED FAST CIPHER

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Journal of Electronics(china) 2000年第1期17卷 94-96页

作者： Wu Wenling li Bao Feng Denguo {2. sihan(engineering research center for information security technology,chinese academy of {12., beijing 100080)

Decorrelated Fast Cipher(DFC) is a candidate for the Advanced Encryption Standard (AES). It is shown that the cryptographic properties of the confusion permutation of DFC are weak in this paper. With the same F-function of DFC, a Feistel cipher VDFC which has no resistance against differential cryptanalysis is constructed. This demonstrates the importance of the key addition into DFC sufficiently. As a result, DFC may not be qualified candidate for the AES.

关键词： Round function Permutation Differential cryptanalysis Nonlinearity

基于TPM虚拟单调计数器的电子钱包方案的分析和扩展

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通信学报 2009年第S1期30卷 1-8页

作者：刘冬梅卿斯汉杨涛李小群中国科学院软件研究所基础软件国家工程研究中心北京100080 中国科学院研究生院北京100039 中国科学院软件研究所信息安全技术工程研究中心北京100080 中国科学院计算机网络信息中心e-Science应用推进总体组北京100190

针对一种基于虚拟单调计数器的电子钱包方案存在的不足,对其进行了扩展,原方案商品原子性无法得到满足,且不能够防止货币消失的问题,即其货币原子性只能得到部分满足。在原方案的基础上,将货物的交换过程考虑进来,扩展后的方案既满足货... 详细信息

针对一种基于虚拟单调计数器的电子钱包方案存在的不足,对其进行了扩展,原方案商品原子性无法得到满足,且不能够防止货币消失的问题,即其货币原子性只能得到部分满足。在原方案的基础上,将货物的交换过程考虑进来,扩展后的方案既满足货币原子性,又满足商品原子性,同时能够为顾客提供隐私保护。

关键词：电子现金电子支付可信计算 TPM 公平性原子性匿名性

A formal model for integrity protection based on DTE technique

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Science in china(Series F) 2006年第5期49卷 545-565页

作者： JI qingguang qing {2. HE Yeping engineering research {2. for information security technology Institute of Software Chinese Academy of Sciences Beijing 100080 China Infrastrucure software engineering {2. Institute of Software Chinese Academy of Sciences Beijing 100080 China

In order to provide integrity protection for the secure operating system to satisfy the structured protection class＇ requirements, a DTE technique based integrity protection formalization model is proposed after the implications and structures of the integrity policy have been analyzed in detail. This model consists of some basic rules for configuring DTE and a state transition model, which are used to instruct how the domains and types are set, and how security invariants obtained from initial configuration are maintained in the process of system transition respectively. In this model, ten invariants are introduced, especially, some new invariants dealing with information flow are proposed, and their relations with corresponding invariants described in literatures are also discussed. The thirteen transition rules with well-formed atomicity are presented in a well-operational manner. The basic security theorems correspond to these invariants and transition rules are proved. The rationalities for proposing the invariants are further annotated via analyzing the differences between this model and ones described in literatures. At last but not least, future works are prospected, especially, it is pointed out that it is possible to use this model to analyze SE-linux security.

关键词： formal model integrity policy information flow domain type.

A Kind of Multi-party Non-repudiation Protocol with Consistent Evidence

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china Communications 2009年第4期6卷 88-96页

作者： liu Dongmei qing {2. National engineering research {2. for Fundamental software Institute of Software The Chinese Academy of Science Beijing 100080 China engineering research {2. for information security technology Institute of Software The Chinese Academy of Science Beijing 100080 China Graduate School The Chinese Academy of Science Beijing 100039China

With development of electronic com- merce, non-repudiation protocol as the basal component of non-repudiation service has done more and more important functions. Comparing with lots of work on two-party non-repudiation, there are less work on multi-party non-repudiation protocol. Multi-party protocol is more complex and facing more challenge of collusion attack. In this paper we give a kind of multi-party non-repudiation protocol based on off-line TTP with consistent evidence. Consistent evidence is a property that can not only simplify the process of disputation resolving, but also make the service more friendly to users, which means that whether or not TTP involves, evidences participants obtained are consistent. In the meanwhile we analyze the collusion attack that multi-party protocol facing, our protocol can prevent collusion attack.

关键词： multi-party fair non-repudiation protocol consistent evidence collusion attack freehess fairness

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基于图注意力网络的城市内涝积水预测与研究

人民黄河 2024年第4期46卷 43-48页

作者：胡昊孙爽马鑫李擎徐鹏黄河水利职业技术学院河南开封475004 华北水利水电大学河南郑州450045 河南省跨流域区域引调水运行与生态安全工程研究中心河南开封475004 中国水利水电科学研究院北京100038 中水北方勘测设计研究有限责任公司天津300222

极端暴雨天气多发频发造成的城市内涝,严重威胁居民的人身财产安全,准确高效的内涝点积水面积预测在提高城市灾害应急处置能力中发挥着至关重要的作用。为了提高城市内涝点积水预测的准确性和直观性,提出一种基于GAT和LSTM网络的GATLST... 详细信息

极端暴雨天气多发频发造成的城市内涝,严重威胁居民的人身财产安全,准确高效的内涝点积水面积预测在提高城市灾害应急处置能力中发挥着至关重要的作用。为了提高城市内涝点积水预测的准确性和直观性,提出一种基于GAT和LSTM网络的GATLSTM组合预测模型,通过GAT提取积水信息局部空间特征,并通过节点分配权重的方式加强对关键信息序列的记忆,随后采用LSTM提取积水面积序列的时间特征,对内涝点积水面积进行预测。以开封市区某内涝点的积水数据建立模型并评估验证,将GATLSTM模型和LSTM、GAT以及GCNLSTM模型进行对比,结果表明:GATLSTM模型的预测精度优于另外3种模型,能够准确地对内涝点积水面积进行预测,可以为防汛工作和应急响应措施的制定提供科学依据。

关键词：积水预测城市暴雨图注意力网络长短期记忆网络

基于CNN-GRU-ATT的城市暴雨积水预测研究

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华北水利水电大学学报（自然科学版） 2024年第4期45卷 27-35页

作者：胡昊陈军朋李擎马鑫徐鹏刘明潇黄河水利职业技术学院河南开封475004 华北水利水电大学河南郑州450046 河南省跨流域区域引调水运行与生态安全工程研究中心河南开封475004 中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100038

多发频发的极端暴雨事件导致很多城市普遍面临严重内涝问题。能否准确高效地预测城市积水点的水位变化,是城市内涝防治的重要组成部分。为有效提升城市暴雨积水预测的精度和效率,建立了一种基于卷积神经网络(CNN)-门控循环单元(GRU)-注... 详细信息

多发频发的极端暴雨事件导致很多城市普遍面临严重内涝问题。能否准确高效地预测城市积水点的水位变化,是城市内涝防治的重要组成部分。为有效提升城市暴雨积水预测的精度和效率,建立了一种基于卷积神经网络(CNN)-门控循环单元(GRU)-注意力机制(ATT)的城市暴雨积水预测模型。首先利用CNN与GRU提取水位数据的局部空间特征和深层时间特征,然后引入ATT加强对降雨序列中关键信息的记忆,从而完成城市积水点的水位预测。利用开封市某积水点的实测水位对模型进行了验证,并与以往的CNN-GRU、ATT-CNN-LSTM以及CNN-LSTM模型进行了对比分析。结果表明,CNN-GRU-ATT模型的损失函数在epoch=2.处即达到收敛,损失函数值最终稳定在0.0002.右,收敛效果较好。此外,与其他3种模型相比,CNN-GRU-ATT模型的预测精度评价指标表现均为最优,且模型仍能保持较高的运算效率。其中均方根误差为1.39%,平均绝对百分比误差为4.32.,决定系数为0.9954。这表明CNN-GRU-ATT模型能够准确、高效地预测出积水点的水位变化情况,可为暴雨内涝预警和制定防汛排涝方案提供有效的科学依据。

关键词：城市暴雨积水预测卷积神经网络门控循环单元注意力机制

Active learning to overcome exponential-wall problem for effective structure prediction of chemical-disordered materials

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npj Computational Materials 2023年第1期9卷 2243-2251页

作者： Xiaoze Yuan Yuwei Zhou qing Peng Yong Yang Yongwang li Xiaodong Wen State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China National Energy center for Coal to Clean Fuels Synfuels China Technology Co.LtdHuairou DistrictBeijing 101400China The State Key Laboratory of Nolinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China beijing Advanced Innovation center for Materials Genome {2. Industry–University Cooperation Base between Beijing Information S&T University and Synfuels China Technology Co.LtdBeijingChina School of engineering sciences University of Chinese Academy of SciencesBeijing 100049China

Chemical-disordered materials have a wide range of applications whereas the determination of their structures or configurations isone of the most important and challenging problems. Traditional methods are extremely inefficient or intractable for large systemsdue to the notorious exponential-wall issue that the number of possible structures increase exponentially for N-body ***, we introduce an efficient approach to predict the thermodynamically stable structures of chemical-disordered materials viaactive-learning accompanied by first-principles calculations. Our method, named LAsou, can efficiently compress the samplingspace and dramatically reduce the computational cost. Three distinct and typical finite-size systems are investigated, including theanion-disordered BaSc(O_(x)F_(1−x))3 (x = 0.667), the cation-disordered Ca_(1−x)Mn_(x)CO_(3) (x = 0.2.) with larger size and the defect-disordered ε-FeC_(x) (x = 0.5) with larger space. The commonly used enumeration method requires to explicitly calculate 2.64, 1033,and 10496 configurations, respectively, while the LAsou method just needs to explicitly calculate about 15, 2., and 10configurations, respectively. Besides the finite-size system, our LAsou method is ready for quasi-infinite size systems empoweringmaterials design.

关键词： disordered exponential configuration

基于角色和数据可视域的农业科研协同办公平台设计

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西南师范大学学报（自然科学版） 2019年第9期44卷 82-88页

作者：李昀吴华瑞邓颖李庆学顾静秋北京市农林科学院北京100097 国家农业信息化工程技术研究中心北京100097 北京市农业信息技术研究中心北京100097 农业农村部农业信息软硬件产品质量检测重点实验室北京100097

农业科研单位信息类型和用户组成复杂,业务流程繁琐,给农业科研单位的协同办公、信息共享利用和信息安全管理等带来许多问题和困难.为了适应科技管理工作发展和科技信息共享服务的需要,系统研究和构建了基于角色和数据可视域,针对多源... 详细信息

农业科研单位信息类型和用户组成复杂,业务流程繁琐,给农业科研单位的协同办公、信息共享利用和信息安全管理等带来许多问题和困难.为了适应科技管理工作发展和科技信息共享服务的需要,系统研究和构建了基于角色和数据可视域,针对多源、复杂和多层级用户的高效管理流程与信息安全主动管理系统;将平台用户横向按部门、纵向按管理等级等进行划分,并对数据资源进行可视域限定,形成用户和数据双向控制的用户权限管理及数据安全控制体系.构建了既可以实现高效信息加载和共享,又可保持信息安全的农业科研协同办公平台.

关键词：信息流数据可视域协同办公数据分发