Internet安全分析与安全防范对策

主要讨论分析Ｉｎｔｅｒｎｅｔ安全问题。从分析Ｉｎｔｅｒｎｅｔ网上存在的安全威胁入手,介绍了几种常见的安全防范措施,并详细讨论了实现Ｉｎｔｅｒｎｅｔ应采用的安全策略和相应的安全机制,最后对现行的主要网络安全防范措施的利弊进行了讨论     

信息安全管理方案研究与发展趋势分析

信息安全是信息社会中备受关注的主要问题,该文着重研究了信息安全的管理方案以及发展趋势。首先讨论了信息环境的安全管理,其次从信息存储和网络环境两个方面讨论了信息操作的安全管理方案,然后分析了基于实物和数字密钥进行身份识别所导致的信息安全管理问题,讨论了以生物特征实施信息安全管理的发展趋势。     

基于ASP＋SQL Server的在线考试系统的安全策略探讨

目前网络在线考试系统应用越来越广泛。本文讨论了基于ASP＋SQL Server的在线考试系统的安全目标,从ASP脚本的安全策略和SQL Server的安全配置两方面来讨论考试系统的安全性能。     

网格环境中的安全性问题研究

分析了网格环境下的安全性问题,即现有技术和安全协议的集成及扩展;不同主机环境协同工作的能力;相互影响的主机环境之间的信任关系。通过建立网格安全模型讨论了网格安全的服务特性,最后还讨论了网格安全解决方案的发展趋势,即将XML安全标准和Web服务的安全性规范融合到网格安全的体系结构中。     

电子商务的安全问题

讨论了电子商务中的安全技术和电子商务安全需要解决的问题。     

内联网Intranet的安全技术

在分析Intranet所面临安全威胁的基础上，讨论安全解决途径．     

Cisco路由器及交换机安全加固探讨

网络层面的安全主要有两个方面,一是数据层面的安全,使用ACL等技术手段,辅助应用系统增强系统的整体安全;二是控制层面的安全,通过限制对网络设备自身的访问,增强网络设备自身的安全性。本文主要集中讨论控制层面即设备自身的安全这部分,仍以最大市场占有率的思科设备为例进行讨论。     

基于Qmail-LDAP的大规模邮件系统的安全设计

讨论了基于LDAP的Qmail平台的安全邮件系统的实现和应用问题.首先介绍了SSL/TLS(安全套接字层/安全传输层)的模型,分析并给出了基于LDAP的POP、SMTP、IMAP的邮件服务协议安全的解决方法,讨论了LDAP协议的安全设计等相关问题.运用Stunnel和OpenSSL等开源软件包实现安全设计.     

我国道路交通安全的现状与改善对策

通过对日本、美国、英国、法国、意大利和德国等经济发达国家过去几十年道路交通安全状况发展历程的分析，提出并讨论以汽车为主要交通工具的现代道路交通系统、交通安全状况变化的基本规律。在此基础上，讨论与分析了我国现代道路交通系统发展状况与道路交通安全现状，最后讨论了我国近期进一步改善道路交通安全状况的基本对策。     

实验室通风柜的设计和使用

从实验的要求出发，讨论了实验室通风柜的设计类型、材料要求以及设计时必须考虑的安全问题及注意事项；详细讨论了实验室通风柜的安全使用和事故的防范与处理。     

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     

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