安全性

Upon completion of this course, the student should be able to: distinguish between reliability and safety and critically read accident reports, perform a hazard analysis on a computer-based system, write requirements for a safety-critical system and trace safety constraints to design, work with human factors experts in the design of safe human-computer interaction, apply the principles of safe design to both systems and software, critique and evaluate a system design for safety, and design a process for building a safety-critical system.

通过完成这门课程，学生能够：区别可靠性和安全性，精读意外事件报告，运行一个以电脑为基础的系统的危险分析，写出一个安全危急系统的必备条件，并通过追踪安全限制，与人类因素专家合作设计安全的人机交互，在系统和软体中应用安全设计理论，评估一个设计系统的安全性和设计一个建立安全危急系统的步骤。

Mostly I accomplish following tasks:(1)After analysis of the mobile agent platform of IBM, I find problem in safety precautions. Aglet uses unilateral secure safeguard, that is to say, which emphasize on system protecting and lose sight of the security of itself.

主要完成的工作有：(1)本文在对IBM的移动Agent平台进行深入的研究后，发现在安全性措施的处理上，Aglet实现了单向的安全性保护，也就是说，它着重强调了对于系统的保护，忽略了对于Aglet本身的保护，比如在传输过程中的保护。

The basic approach of protecting people from being hurt or killed in an accident is to improve crashworthiness of vehicles. This paper starts with discussing theories and methods for vehicle passive safety design, which included experiential methods, analytic methods, multi-body dynamics methods, crash test methods and the finite element method. Emphasis will be paid to the basic FEM theories and algorithms of impact problems. Topics discussed include the governing equation, element discretization, hourglass control, time integration, material model, shell element algorithms and contact-impact algorithms. For more reliable simulation results, this paper then conducts study on how to accurately get material model parameters by combining the FEM method with experimental method, and develops relevant material test machine and parameter calculating software. Based on that, basic typical impact simulation and test validation study are conducted. On the basis of the above work, the paper studies the thin-shell structures'crashworthiness, which was affected by the following factors: spot-weld features, shell thickness, cross-section and pre-deformation. As to vehicle parts'crashworthiness, the paper conducts simulation study of designing energy-absorbing steering system and adaptive airbag system. A practical energy-absorbing steering wheel is designed as an example. In further depth research, the paper suggests several inverse quantificational methods for vehicle crashworthiness design based on the ideal crash characteristics. The above theories and methods are applied with good results through several practical vehicles' crashworthiness design and improvement.

文中对汽车碰撞安全性的设计理论和方法进行了归类和总结，其中包括经验法、解析法、多刚体动力学法、试验法以及有限元方法等；重点介绍了碰撞有限元法的基本理论和有关算法，涉及到有限元求解控制方程、单元离散、沙漏模态控制、时间积分、材料模型和应力修正、薄壳单元算法以及接触碰撞界面算法等，探讨了有限元计算中的材料模型参数获取技术，开发了相应的材料试验装置及材料模型参数反求软件，在此基础上进行了基本的碰撞仿真算例和试验对比研究；文中通过应用有限元方法研究了薄壁构件的碰撞吸能特性，指出了设计薄壁吸能构件时需要考虑的几个主要影响因素，即焊点、壁厚、横截面和预变形等；在关于车辆部件的碰撞安全性能设计中进行了吸能转向机构和自适应安全气囊的仿真研究，提出了吸能转向机构和自适应安全气囊的仿真研究方法；文中最后探讨了整车碰撞性能的设计与改进方法，提出了以理想碰撞特性为目标，采用分段加速度或者根据碰撞时间进行设计的反推设计法、部件吸能仿真优化设计法等量化设计方法，并通过综合应用文中所讨论的相关技术进行了整车碰撞性能的设计与改进实例研究，所选定的车型是大众化的普通轿车和碰撞安全性基础较差的微型面包车，研究结果表明，本文所提出的设计与改进方法是适用而有效的，具有重要的工程实用意义和价值。

This paper proposes an universal e-cash system based on partially blind signature which can be divided to small pieces of arbitrary number one time, so-called single-divisibility.

针对通用电子现金系统的难点在于其可分性，本文提出的方案以SK00系统为基础，实现其转移性(SK00公开问题)，并给商家颁发电子执照行使银行的部分职能，进而提出了一个显式可分(即一次性任意分割电子现金)的离线电子货币系统；同时利用以前的技术实现了一个采用树型结构的可分电子现金系统，并比较了这两个方案和以前方案的效率；二者安全性基于离散对数问题和强无碰撞Hash函数安全性；最后本文利用代理签名给出了一个新的部分盲签名方案。

Through simulation tests with curb, the real time data was obtained. Meanwhile, the author concluded that curb set is median strip has great influence on the safety of driving, analyzed the relationship between collision angle and safety, appraised the safety guard rail and finally offered the foundation of drawing up new standards.

在这些模型中，进行多角度、不同速度下对有、无路缘石的情况进行三维动态碰撞仿真实验，并实时获得需要的碰撞数据，得出了我国高速公路中央分隔带设置路缘石在规定位置对行车安全性的影响，车辆碰撞角度的大小对安全性的影响，并对护栏安全性进行评估和为今后规范的制定提供了依据。

Because designs of operating systems are quite different, the evaluating system is semiautomatic.

操作系统安全性的测评是实现安全操作系统的一个极为重要的环节，如果不测评、验证所开发操作系统的安全性和该安全性的可信度，那么开发出的安全操作

Along with the password attack method unceasing renewal, the computation ability unceasing enhancement as well as to the operating speed request, the tradition disperses row algorithm MD5, SHA has demonstrated their shortcoming and the insufficiency day by day, and thestructure of hash function is mostly based on block cipher algorithm DES, but the HASH function security is established above the grouping function security, because the DES operand is very big, the operating speed very slowly by and its itself some characteristics, therefore disperses a row function based on the DES algorithm to have potential unsecurity.

随着密码攻击手段的不断更新、计算能力的不断提高以及对运算速度的要求，传统的散列算法MD5，SHA已日益显示出它们的缺点和不足，并且过去hash函数的构造多是基于分组密码算法DES的，而hash函数的安全性是建立在分组函数的安全性之上的，由于DES运算量很大、运算速度很慢以及其本身的一些特性，因此基于DES算法的散列函数具有潜在的不安全性。

Along with the password attack method unceasing renewal,the computation ability unceasing enhancement as well as to theoperating speed request, the tradition disperses row algorithm MD5,SHA has demonstrated their shortcoming and the insufficiency day byday, and thestructure of hash function is mostly based on block cipheralgorithm DES, but the HASH function security is established above the grouping function security,because the DES operand is very big, the operating speed veryslowly by and its itself some characteristics, thereforedisperses a row function based on the DES algorithm to havepotential unsecurity.

摘要随着密码攻击手段的不断更新、计算能力的不断提高以及对运算速度的要求，传统的散列算法MD5，SHA已日益显示出它们的缺点和不足，并且过去hash函数的构造多是基于分组密码算法DES的，而hash函数的安全性是建立在分组函数的安全性之上的，由于DES运算量很大、运算速度很慢以及其本身的一些特性，因此基于DES算法的散列函数具有潜在的不安全性。

So the new protocol achieves key independence, and it provides perfect forward secrecy, KGC-forward secrecy and resistance to passive and active attacks as well.

同时新协议满足完善的前向安全性、主密钥前向安全性，以及抗主动和被动攻击等安全性。

In order to gain the result of the safety assessment of CFST arch bridge, based on the traditional safety evaluation methods, artificial neural network and analytic hierarchy process, a safety evaluation method based on radial basis function neural network was presented.

以全桥安全性评价为总体目标，在以往桥梁安全性评价方法的基础上，引入人工神经网络理论，并结合层次分析法，提出了基于径向基网络的钢管混凝土拱桥安全性评价方法。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了