基于ODBC的医疗诊断专家系统数据库接口的研究和探讨

本文分析了ＭＤＥＳ的，提出了面向对象知识的ＯＤＢＣ数据库接口解决方案，并且介绍了用ＶＣ＋＋１．５开发ＭＤＥＳ的数据库接口的实践过程。     

也谈在C程序中使用DOS内部命令

本文依据ＤＯＳ命令解释程序ＣＯＭＭＡＮＤ．ＣＯＭ可个有命令行参数的特点，给出了在Ｃ程序中使用ＤＯＳ内部命令的一种简便、高效的方法。方法是通过调用Ｃ函数ｓｙｓｔｅｍ或ｓｐａｗｎｌ加载带有命令行参数的ＣＯＭＭＡＮＤ．ＣＯＭ实现的，文后给出了示例程序。     

DCOM应用开发

本文首先介绍ＡｃｔｉｖｅＸ和ＤＣＯＭ技术，然后介绍如何在ＶＢ５环境下开发和发布ＤＣＯＭ应用程序，最后讨论在应用中出现的问题及解决办法。     

多通道振动测量与分析系统中振型动画实现方法

由南京航空航天大学振动工程研究所开发完成的多通道振动测量与分析系统（ＭＶＭＡＳ）的适于做大型结构的模态分析。本文介绍了该系统实现振动动画的基本原理及在ＤＯＳ环境下实现动画的方法，该方法充分利用ＶＧＡ显示器特性，具有动画速度快的特点，最后介绍了ＭＶＭＡＳ在ＭＳ－ＷｉｎｄｏｗｓＳ３．１环境下利用ＡＰＩ函数实现动画的方法。     

在真正的MSDOS5.0或DRDOS6.0下运行汉字系统

文分析了在ＭＳＤＯＳ５．０或ＤＲＤＯＳ６．０下运行流行的王码５．０，金山５．０和２．１３Ｈ等汉字系统不能完全，充分发挥ＭＳＤＯＳ５．０和ＤＲＤＯＳ６．０性能的原因，给出了具体的实施方案，较好地解决了这一国内广大用户普遍关心的问题。     

大叶片CAD／CAM一体化加工系统软件

详细介绍了汽轮机未级大叶片的ＣＡＤ／ＣＡＭ一体化加工方法，尤其对大叶片的“５个难点”部位的空间曲线，曲面的Ｂ样条拟合方法及程序生成中的简化方法分别进行了研究介绍，并分析了可行性，进而介绍了大叶片ＣＡＤ／ＣＡＭ一体化加工系统的结构，功能特点和数控加工程序的生成及相应的框图。     

一个直接存取Internet节点数据的DBMS原型

基于现存ＤＢＭＳ和Ｉｎｔｅｒｎｅｔ数据模型的特点和互补性，本文提出了一个直接存取Ｉｎｔｅｒｎｅｔ节点数据的ＤＢＭＳ原型－ＷｅｂＨＢａｓｅ，分析了ＷｅｂＨＢａｓｅ的特殊任务，主要难点及特殊解决方法，基于ＷｅｂＨＢａｓｅ的预研经验，提出了Ｗｅｂ模型与ＤＢＭＳ各自改革、互相靠近，逐步融合，实现未来Ｗｅｂ－ＤＢＭＳ的若干建议。     

有限自动机定义函数的线性本原圈积分解

本文讨论有限自动机显表出定义函数ｆ的线性本原圈积分解问题。在该圈积分解之下,函数ｆ被表成线性外函数因子ｆＬ与线性本原内涵数因子ｆＮ的圈积,这里函数ｆＬ定义了一个线性弱可逆有限自动机ＭｆＬ,而函数ｆＮ定义了一个非线性有限自动机ＭｆＮ且其不能再分解成一非平凡的线性外函数与一非线性内函数的圈积。本文证明了一函数ｆ的任两线性本原内因子互为对方的线性本原内因子,从而证明了函数ｆ的线性本原圈积分解的唯一性。本     

MS DOS 6.0—一个用户版的操作系统

该文介绍了ＭＯＳ ＤＯＳ ６．０版从用户角度出发在ＭＳ ＤＯＳ ５．０基础上所作的改进，对其在存储管理方面的改善及自动配置功能模块ＭｅｍＭａｋｅｒ、实时压缩模块ＤｏｕｂｌｅＳｐａｃｅ、实用驱动程序和多配置、交互式引导特征等作了较为详细的介绍，并对ＭＳ ＤＯＳ ６．０特意为便携式计算机新增加的一些功能和在ＭＳ ＤＯＳ ５．０基础上添加的一些命令作了简要说明。     

异种平台的计算机网络系统建设

以ＦＤＤＩ为主干、１０Ｍ以太网连接到桌面，以及通过电话网可远程联接的覆盖５座科研楼和机关楼的分级交换网，并对其网络体系结构、特点，网络软件硬件配置及应用情况作了总结，以期对读者的网络选型和网络方案配置有所帮助。     

关于Hash函数MD5的解析

在王小云写的关于分析MD5算法文章的基础上,对MD5算法的破译进行进一步的解析.以MD5算法第八步为例,介绍了F函数的性质和差分路径的有效控制.从手工推算和程序实现两方面时MD5算法进行了解析和测试,对王的文章进行了部分修正,进一步说明了满足差分特征的条件和关键点.这对MD5和其他Hash函数的分析破译有着重要的作用.     

On security arguments of the second round SHA-3 candidates

In 2007, the US National Institute for Standards and Technology (NIST) announced a call for the design of a new cryptographic hash algorithm in response to vulnerabilities like differential attacks identified in existing hash functions, such as MD5 and SHA-1. NIST received many submissions, 51 of which got accepted to the first round. 14 candidates were left in the second round, out of which five candidates have been recently chosen for the final round. An important criterion in the selection process is the SHA-3 hash function security. We identify two important classes of security arguments for the new designs: (1) the possible reductions of the hash function security to the security of its underlying building blocks and (2) arguments against differential attack on building blocks. In this paper, we compare the state of the art provable security reductions for the second round candidates and review arguments and bounds against classes of differential attacks. We discuss all the SHA-3 candidates at a high functional level, analyze, and summarize the security reduction results and bounds against differential attacks. Additionally, we generalize the well-known proof of collision resistance preservation, such that all SHA-3 candidates with a suffix-free padding are covered.     

基于DES和MD5算法的安全注册系统

文章提出一种基于网络的软件保护方案,用户通过Internet连接至服务器端的注册机进行注册。方案中运用密码学中的MD5算法进行首轮加密并做循环移位处理,并用DES算法再次加密,最后以数据库的方式实现注册信息的管理。系统采用密钥验证机制,多个检查点调用验证函数来检查密钥的合法性。通过这一系列的手段使得软件能够比较有效地防止非法用户注册,达到软件保护的目的。     

Improved Collision Attack on Hash Function MD5

In this paper, we present a fast attack algorithm to find two-block collision of hash function MD5. The algorithm is based on the two-block collision differential path of MD5 that was presented by Wang et al. in the Conference EUROCRYPT 2005. We found that the derived conditions for the desired collision differential path were not sufficient to guarantee the path to hold and that some conditions could be modified to enlarge the collision set. By using technique of small range searching and omitting the computing steps to check the characteristics in the attack algorithm, we can speed up the attack of MD5 efficiently. Compared with the Advanced Message Modification technique presented by Wang et al., the small range searching technique can correct 4 more conditions for the first iteration differential and 3 more conditions for the second iteration differential, thus improving the probability and the complexity to find collisions. The whole attack on the MD5 can be accomplished within 5 hours using a PC with Pentium4 1.70GHz CPU.     

密码技术在当前信息安全领域中的应用研究

密码技术在信息安全中有着举足轻重的作用。文章介绍了密码技术的相关理论及应用现状,并以应用比较广泛的单向散列函数MD5为例介绍了单向散列函数在当前的应用,特别以网页设计中用户认证为例,对单向散列函数MD5所起的作用进行了比较。     

密码杂凑函数及其安全性分析

文章提出了针对密码杂凑函数及其安全性进行研究的重要意义,列举了单向杂凑函数、MD5、SHA-1等技术原理进行了技术分析,并从攻击手段入手,分析了密码杂凑函数的安全性,提出对SHA-1与MD-5的＂破解＂应客观看待的观点。     

A UML profile for multidimensional modeling in data warehouses

The multidimensional (MD) modeling, which is the foundation of data warehouses (DWs), MD databases, and On-Line Analytical Processing (OLAP) applications, is based on several properties different from those in traditional database modeling. In the past few years, there have been some proposals, providing their own formal and graphical notations, for representing the main MD properties at the conceptual level. However, unfortunately none of them has been accepted as a standard for conceptual MD modeling.

In this paper, we present an extension of the Unified Modeling Language (UML) using a UML profile. This profile is defined by a set of stereotypes, constraints and tagged values to elegantly represent main MD properties at the conceptual level. We make use of the Object Constraint Language (OCL) to specify the constraints attached to the defined stereotypes, thereby avoiding an arbitrary use of these stereotypes. We have based our proposal in UML for two main reasons: (i) UML is a well known standard modeling language known by most database designers, thereby designers can avoid learning a new notation, and (ii) UML can be easily extended so that it can be tailored for a specific domain with concrete peculiarities such as the multidimensional modeling for data warehouses. Moreover, our proposal is Model Driven Architecture (MDA) compliant and we use the Query View Transformation (QVT) approach for an automatic generation of the implementation in a target platform. Throughout the paper, we will describe how to easily accomplish the MD modeling of DWs at the conceptual level. Finally, we show how to use our extension in Rational Rose for MD modeling.     

一种基于嵌入式Linux的MD机制研究

提出一种嵌入式Linux下的MD算法和实现机制,并就MD自启动方式、MD与Raidtools的整舍以及进程管理等方面进行了有效改进和优化。在其方案基础上,设计一个基于嵌入式Linux平台的RAID5存储系统。     

一种Web站点网页资源保护设计方案

针对当前网络主页不断受到黑客攻击，给网络带来不良影响，危害了互联网事业的健康发展，提出了一种有效的解决方案－基于散列算法的文件系统扫描检测与恢复系统，预测网络黑客的攻击，并在一旦网络被黑客攻破后及时报警与恢复；有效地保护网页资源。     

带认证邮局协议的密钥恢复攻击

作者提出了一种新的针对带认证邮局协议的密钥恢复攻击,能够更快地恢复出密钥并能够恢复更多的密钥字符.基于通道技术和高级消息修改技术,提出了一种“群满足方案”来确定性地满足分而治之策略下最后一个通道首三步的所有充分条件,籍此提高MD5 (Message Digest Algorithm 5)碰撞对搜索的效率.并提出了一些新的通道来控制MD5碰撞对消息的更多比特的取值,比如可以构造出352比特值确定的MD5碰撞对.通过这些技术改进了多位信息确定的MD5碰撞对搜索效率,应用到APOP的密钥恢复攻击中不仅能够快速恢复长达31个字符的密钥,而且能够在实际时间内恢复长达43个字符的密钥.