DBMS安全审计功能测试用例生成方法

数据库管理系统（DBMS）安全审计功能的符合性测试要求测评人员设计有效覆盖安全功能规范的测试用例。本文提出一种基于安全审计规范使用标记迁移系统（LTS）建立形式化模型的DBMS安全审计测试用例自动化生成方法。该方法根据数据库分级评估的安全目标建立审计功能组件的LTS模型,再依据LTS模型启发式路径搜索算法从模型的路径中...     

基于LogicSQL数据库的强制访问控制研究

访问控制是保障数据库安全的核心技术之一.本文综合比较分析了几种数据库访问控制模型,结合在LogicSQL数据库内核加入强制访问控制策略(MAC),同时对Bell-LaPadula模型进行改进,实现了基于角色的强制访问控制下数据库的权限管理,使LogicSQL成为多级安全数据库管理系统(MLS DBMS).该多级安全数据库管理系统已在企业搜索与公安信息系统中得到应用.     

工作流管理系统中基于角色的访问控制

在已有的基于角色访问控制模型基础上，提出了一个基于角色的安全工作流管理系统模型．讨论了安全模型的安全目标，给出了模型的形式化描述，分析了用户牵引方式和服务器牵引方式各自的优缺点，详细描述了在服务器牵引方式下的工作方式，同时讨论了动态授权时的一些安全机制．该安全模型较好地将基于角色的访问控制策略运用到工作流管理系统中，动态授权机制使得模型的安全性进一步提高．     

基于模式识别的Lebesgue积分在PVS中的形式化证明与分析

针对传统模型验证方法存在效率低和模型较为复杂的缺点,将Lebesgue积分的运算特征引入模型验证和测试,提出一种基于Lebesgue积分的形式化验证和测试方法。通过不等式计算、闭区间子集可积分性、多重分部、线性运算、Cauchy可积分准则以及极限定理等方面的形式化,实现Lebesgue积分的运算特征在PVS(Prototype Verification System)定理证明器中的形式化。以标准反相积分器为应用模型验证数学理论和公式推导的正确性,通过数理分析验证Lebesgue积分形式化定理库在计算机信息安全领域应用的正确性。测试结果证明了Lebesgue积分在PVS中进行形式化的可行性和有效性。     

基于原型验证系统的自稳定算法形式化验证

介绍了分布式系统的自稳定性以及原型验证系统(PVS),阐述了从形式化角度验证系统性质的方法.使用PVS对分布式系统及系统中的自稳定算法进行形式化描述和建模,并成功地证明了系统的自稳定性.同时,通过机械化的验证和分析结果,可以得出形式化证明的优势.     

基于元模型架构的UML类图到PVS规范的转化方法

UML是一种非形式化的面向对象建模语言,它缺少精确的语义定义;PVS规范则是一种具有精确语义定义的形式化规范语言,通过PVS规范给UML图形赋予精确的语义可以结合两者的优势.为此,提出了一个将UML类图转换成PVS规范的框架.按照UML的4层架构,依次对元元模型、元模型以及UML图形进行转换,并且前一次转换所得到的规范可以为后面的转换提供上下文背景.与其他方法相比,这种分层转化的方法降低了转换难度,保证了转换的正确性,保持了UML模型更完整的语义成分.     

Lebesgue积分在PVS中的证明分析

为了有效解决函数系统建模、信号实时分析等数理支持领域验证与测试的定理证明形式化问题,设计并实现了利用Lebesgue积分的运算特征在PVS定理证明器中进行形式化证明与分析.主要对其分裂定理、不等式计算、闭区间子集可积分性、多重分部、线性运算、Cauchy可积分准则和极限定理等多个方面进行了形式化,且依据数学定理与推论形式化,说明Lebesgue积分在PVS中的形式化是可行的、有效的.以标准反相积分器为应用模型,对其通用电路原理与机制进行了形式化证明,通过数理分析测试了本文Lebesgue积分形式化定理库的正确性.     

安全苛求系统的形式化开发方法

从系统工程的角度出发,基于形式化理论,对安全苛求系统的开发方法进行了研究.首先介绍了安全苛求系统的形式化方法,分析了形式化方法对安全苛求系统的作用;提出了一种安全苛求系统的形式化开发模型(FDM),给出了具体的应用实例.     

安全数据库数据层推理泄漏检测方法

普通权限用户通过查询并结合数据库的其他知识,绕过安全机制,进行间接推理获取非授权信息,从而造成安全数据库敏感信息的推理泄漏.针对这一问题,提出了一种数据层的推理泄漏检测方法.该方法在形式化描述的基础上,根据数据库的约束规则和用户查询数据,基于逻辑推理实现了推理泄漏的检测.理论分析和测试结果表明该方法能够全面、有效地获取用户查询结果中实际蕴含规则,运用这些规则,可以使推理检测的正确率达到81.3%.     

采用模型检测器的软件安全模型验证方法

针对软件开发过程中安全性分析与设计不足的问题,在研究现有软件安全性建模及形式化验证技术的基础上,提出了一种适用于面向对象的软件安全性建模与验证方法.建立软件安全属性的非形式化UML模型,采用安全扩展有限自动机创建其形式化模型,并使用线性时序逻辑描述安全属性,将形式化模型与安全属性共同作为模型检测器的输入,得到模型是否满足性质的验证结果,从而实现了软件安全设计与验证技术的有机结合.实验结果表明,该方法能够在软件设计初期对所涉及的安全性进行有效分析与验证.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with