一个面向对象的单域数据库密钥管理模型

半通信系统主机密码操作移植到网络数据库环境中进行密钥管理,并提出了一个基于对象的密钥管理模型,利用对成员的访问限制实现密钥的访问控制,替代了用密钥加密钥的工作方式,提高了经济的效果,可移植性和可重用性。最后用该对象的模型述了一个典网络数据库密钥管理系统。     

密钥管理在数据库加密系统中的应用研究

密钥管理是数据库加密系统设计和实现要解决的一个十分关键的问题，也是一个很难解决的问题，密钥管理的好坏直接关系到整个加密系统的性能和密文数据的安全．作者从密钥的产生、分配、存储、转换和更换几个方面讨论了密钥管理，提出了具体的密钥管理方案，并讨论了该方案的安全性．讨论结果表明，该方案是一个能满足数据库加密系统安全要求的行之有效的密钥管理方案．     

基于MYSQL的网络密文数据库研究

密文数据库是增强数据库系统安全性的有效技术途径.介绍网络密文数据库的研究现状和基于服务器的数据库MYSQL所具有的特点,针对采用MYSQL所设计的网络密文数据库,在加密算法的选择、密钥管理及加密粒度等方面给出解决措施.     

面向对象的工艺装备管理数据库设计方法

分析工艺与工艺装备设计过程的本质特征 ,采用面向对象的方法 ,研究工艺装备管理数据库的设计方法。详细论述了工艺装备管理数据库对象模型的建模步骤和将面向对象模型转化为关系数据库模型的方法 ,实用证明按照O -O方法建立的工艺装备管理数据库能适应网络环境下CAPP系统的应用要求     

计及多端互联通信的智能电网AMI新型密钥管理方案

针对智能电网高级量测体系(advanced metering infrastructure, AMI)中智能电表与配电自动化系统、分布式电源监控系统等通信过程中可能存在的信息安全问题，提出了一种计及多端互联通信的智能电网AMI新型密钥管理方案.首先基于电力系统IEC 61850标准建立了智能电表量测信息交互模型，然后根据AMI在电力系统中的密钥实际管理需要，提出了一种适用于AMI环境下的密钥管理架构，并采用数据-密钥双向动态更新策略，降低了网络密钥分发耗损与泄漏风险.通过算法安全性和性能测试可知，该新型密钥管理方法符合电力系统数据量测的安全需要，能够有效保障智能电网AMI中多端互联通信过程中的信息安全.     

分布式环境下数据库加密密钥管理方案

针对分布式环境下数据库加密密钥管理问题，分析了密钥管理的特点，提出了一种基于矩阵模型的密钥转换表方案，并严格论证了其安全性，矩阵中存储的都是密文，敌手不能从中得到有用的信息或推导，系统能够根据用户的数据库访问请求，进行密钥变换，从而安全高效地响应用户的请求。另外，此方案既能够提供各个子数据库系统之间一定程度的数据共享，又能够保持各自的独立性。     

基于IBE算法的无线传感器网络加密方法研究

由于无线传感器网络在电源、计算能力、内存容量和易受攻击等方面的局限性,传统的网络密钥分配和管理方法已不适用.目前人们提出了随机分配等基于对称密钥系统的加密方法.文中试图探讨基于非对称密钥系统的方法.从身份标识的密钥体系IBE(Identity-Based Encryption)出发,给出了一种适用于无线传感器网络的密钥分配和管理方法.首先简要介绍基于身份标识的密钥体系,特别是Boneh-Franklin算法,然后给出密钥分配和加密方法,并从算法的复杂性、安全性、健壮性和内存需求等方面,与随机算法、RAS算法等进行分析比较,应用仿真平台TinyOS的实验结果表明了文中推出方法的可行性和有效性,显示了良好的综合性能,为无线传感器网络的加密提供了新的手段.     

无线传感器网络密钥管理问题研究

无线传感器网络(wireIess sensor network,WSN)应用广泛,其安全问题非常重要,WSN安全问题的核心是密钥管理问题.本文分析了在WSN的应用中密钥管理问题所受的限制,介绍了几种典型的密钥管理模型,并对它们进行了比较和分析,在此基础上指出了WSN密钥管理问题下一步的研究方向.     

基于EBS的无线传感器网络密钥管理方法研究

针对现有无线传感网络(wireless sensor networks, WSN)群组通信中网络环境复杂、资源占用率高以及共谋攻击等问题,提出一种融合三元多项式和EBS(exclusion basis system)管理机制的动态密钥管理方法。通过分析现有方法的不足,从WSN系统模型和EBS密钥管理2个方面对其进行改进,针对WSN系统模型引入层次式拓扑结构,有效解决簇头节点存在的单点失效问题,在此基础上,根据EBS群组密钥管理方法,引入三元多项式算法对EBS管理机制的参数进行优化。仿真结果表明,改进方法与局域化组合密钥管理(localized key management, LOCK)方法相比,改进后的EBS方法可以减少传感器节点的密钥存储量,增加网络共谋链的长度以及提高WSN的网络抗毁性。     

医疗传感器网络认证密钥交换协议

针对一个基于无线传感器网络的医疗监护系统的实际情况,分析了系统的安全需求.基于通用可组合安全模型,定义了医疗传感器网络认证密钥交换理想函数,该理想函数提供了强安全性和实用性.在传感器节点和基站之间,设计了一个通用可组合安全的认证密钥交换协议NB-AKE.NB-AKE协议使用伪随机函数原语实现.该协议提供匿名认证功能,并且具有前向安全性和并发安全性.新协议结构简单,通信量较低,节点端的计算负载较小.     

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.     

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

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