一种RBAC组图模型研究

简要介绍了RBAC模型和角色图模型。提出了一种组图模型,重点分析了组图模型和角色图模型之间的关系。在两者关系的基础上,提出了组．角色分配的平行四边形法则。利用该法则,用户组一角色授权将变得规范化、正规化,且更加易于实施。     

Resonance Treatment for Double Heterogeneity Based on Subgroup Method

The improved subgroup method coupled with Sanchez-Pomraning method (ISSP) was proposed for the resonance self-shielding calculation of double heterogeneity (DH) problems. ISSP employed a fine-mesh energy structure to avoid the extra resonance interference treatment. The DH subgroup fixed source equations and the neutron slowing-down equations were established to obtain the effective resonance cross-section in particle and matrix. Finally, the transport calculation under DH condition was carried out. By contrast with the continuous-energy Monte Carlo method and the ultra-fine group method, numerical verification results indicate that ISSP could provide resonance cross-section in DH condition accurately and effectively.     

基于属性的BGN型密文解密外包方案

云计算的安全问题是制约其发展的关键瓶颈,其中对云计算结果的访问控制是当前研究的一个热点。在经典的类同态BGN方案基础上,结合CP-ABE（Ciphertext-Policy Attribute-Based Encryption）型密文解密外包设计,构造了基于属性的BGN型密文解密外包方案,部分密文的解密被外包到云上进行,减小了用户的存储开销与计算开销,并且只有用户属性满足访问策略时,才会得到正确的解密结果。与现有的基于属性的外包方案相比,新方案能对密文进行任意次加法同态和一次乘法同态操作。最后,分析了方案的安全性。所提方案在子群判定问题假设下达到语义安全,在随机预言机模型下满足属性安全。     

A two-dimensional model of intergroup leadership: The case of national diversity.

The model presented argues that leadership involves bringing together not only diverse individuals but also the subgroups to which they belong. The model further argues that this does not require replacing people’s subgroup identities with a superordinate group identity (turning “us” and “them” into “we”); bringing together diverse individuals and their subgroups can be accomplished by promoting positive relations among subgroups, even as their distinctive identities (their senses of “us” and “them”) remain. The model conceptualizes positive and negative intergroup attitudes as two independent dimensions of intergroup relations, each with distinct antecedents and distinct associated outcomes. Leaders seeking to create a collective from diverse subgroups must therefore (a) reduce negative intergroup attitudes and (b) increase positive intergroup attitudes. The author applies the model to organizational contexts of national diversity, but it can be applied to leadership across other forms of diversity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

双极值模糊软子群和双极值模糊正规软子群

研究了双极值模糊软子群的等价刻画。在双极值模糊软子群的基础上定义了双极值模糊正规软子群,得到了它的一些性质及等价刻画,进一步还研究了在双极值模糊软同态下,双极值模糊正规软子群的像与原像一些性质。     

双极值模糊（反）软子群

在双极值模糊软集理论的基础上,给出了双极值模糊（反）软子群的概念,讨论了它们的一些相关性质及等价刻画。提出了双极值模糊软映射下双极值模糊软集的像与原像的概念,并研究了双极值模糊软同态下双极值模糊（反）软子群的同态像与原像的初等性质。     

复杂几何燃料组件的共振自屏计算

共振参数计算是反应堆堆芯设计计算中的重要内容,传统的共振计算模型只适应于简单几何计算。本工作应用A.Hebert提出的子群共振自屏计算模型研制了复杂几何燃料组件的共振自屏计算程序。该程序能处理含有两种共振核素的复杂几何下的共振自屏。对一系列问题的数值校验计算表明,该模型在低富集度时具有较好的计算精度。     

软集与新型软子群

定义并研究了软集上的一些新的代数运算,给出了二型软子群,正规二型软子群的新概念,得到了它们的一些等价刻画,进一步研究了在软集的各种不同的运算之下软子群、正规软子群的一些初等性质。     

有限群p-可解的几个充分条件

子群的中心化子对群的结构有很强的控制作用.对有限群G的极小子群的中心化子赋予较弱的条件,得到G的p-可解的充分条件.在一定程度推广了李世荣的结果.     

l—群的主极子群格的极小条件

研究了的l-群G的主极子群格PP（G）的极小条件,主要证明了PP（G）满足极小条件当且仅当对于AN∈μГm（G）,N=α^┴,作为应用,还证明了：（1）G是紧生成的l-群,Fν与Fν2是等价的;（2）G是有基的l－群,则P（G）格是完全分配的。