Chosen ciphertext secure fuzzy identity based encryption without ROM

Two new constructions of chosen-ciphertext secure fuzzy identity-based encryption(fuzzy-IBE) schemes without random oracle are proposed.The first scheme combines the modification of chosen-plaintext secure Sahai and Waters'"large universe"construction and authenticated symmetric encryption, and uses consistency checking to handle with ill-formed ciphertexts to achieve chosen-ciphertext security in the selective ID model.The second scheme improves the effciency of first scheme by eliminating consistency checking.This improved scheme is more effcient than existing chosen-ciphertext secure fuzzy-IBE scheme in the standard model.     

An identity-based encryption scheme with compact ciphertexts

This paper proposes an identity-based encryption scheme with the help of bilinear pairings, where the identity information of a user functions as the user's public key. The advantage of an identity-based public key system is that it can avoid public key certificates and certificate management. Our identity-based encryption scheme enjoys short ciphertexts and provable security against chosen-ciphertext attack (CCA).     

Non-interactive and non-malleable commitment scheme based on q-one way group homomorphisms

Commitment scheme is a basic component of many cryptographic protocols, such as coin-tossing, identification schemes, zero-knowledge and multi-party computation. In order to prevent man-in-middle attacks, non-malleability is taken into account. Many forming works focus on designing non-malleable commitments schemes based on number theory assumptions. In this paper we give a general framework to construct non- interactive and non-malleable commitment scheme with respect to opening based on more general assumptions called q-one way group homomorphisms (q-OWGH). Our scheme is more general since many existing commitment schemes can be deduced from our scheme.     

组合效应对腹板削弱型梁柱节点的影响

采用数值模拟方法分析了混凝土楼板组合效应对钢框架腹板开圆孔削弱型梁柱节点的影响,着重讨论了节点承栽力、弹塑性阶段的应变分布、梁塑性区的产生和扩展情况,并与未考虑组合效应此类节点的性能进行了对比．削弱截面与柱的距离和削弱半径是重要的削弱参数,决定了腹板削弱型节点塑性区的扩展特征．研究结果表明,组合效应对腹板开圆孔削弱型梁柱节点区域的应变分布和塑性区扩展影响显著,其削弱参数的确定须充分考虑楼板组合效应．     

用WSE 3.0实现Web服务安全中的签名与加密

签名和加密是实现Web服务安全中的常用技术.Web服务安全开发工具包WSE 3.0的推出,为Web Services安全问题提供了新的解决方案.本文给出了用WSE 3.0实现部分签名和加密的具体过程,具有广泛的实用性.     

一种基于Logistic混沌序列的加密隐藏算法

利用混沌序列的随机性和不可预测性,可将其作为密钥进行数据加密.同时,传统的加密技术所得到的密文容易被攻击者发现,影响了信息的安全性.本文有效地引入信息隐藏方法,提出了基于Logistic混沌序列并将加密与隐藏相结合的算法,防止密文在传送中被监测到,提高了信息的安全性.     

平交路口远引掉头设置方法分析

平交路口远引是解决路口流向禁限后车流转向问题的有效方法。通过对掉头地点的选址规划以及交叉口之间的协调控制进行研究,提出最佳掉头位置应满足的条件以及交叉口协调控制的相位差计算方法。通过对掉头通道通行能力的分析,提出实施掉头信号控制条件和具体实施方法。     

Identity-based broadcast encryption with shorter transmissions

This paper describes two identity-based broadcast encryption(IBBE) schemes for mobile ad hoc networks.The first scheme proposed achieves sub-linear size cipertexts and the second scheme achieves O(1)-size ciphertexts.Furthermore, when the public keys are transmitted, the two schemes have short transmissions and achieve O(1) user storage cost, which are important for a mobile ad hoc network.Finally, the proposed schemes are provable security under the decision generalized bilinear Di?-Hellman(GBDH) assumption in the random oracles model.     

The gap between intractable problem and adaptive chosen ciphertext security

To describe the design approaches of IND-CCA2 (adaptive chosen ciphertext attack) secure public key encryption schemes systematically, the gaps between different kinds of intractable problems and IND-CCA2 security are studied. This paper points out that the construction of IND-CCA2 secure schemes is essentially to bridge these gaps. These gaps are categorized, analyzed and measured. Finally the methods to bridge these gaps are described. This explains the existing design approaches and gives an intuition about the difficulty of designing IND-CCA2 secure public key encryption schemes based on different types of assumptions.     

一种图文信息隐藏算法

针对信息与网络安全的重要性及严峻性,提出了一种汉字信息加密、在BMP图像文件中隐藏、恢复及解密的方法.     

道路平曲线辅点加密的一种方法

现代道路施工,由于施工企业机械化程度的提高,这就要求测量放样快速准确。介绍了平曲线加密的一种简捷方法,分为圆曲线加密与缓和曲线加密,使小半径平曲线辅点的测放简捷易行。     

一个基于Schnorr算法的可公开验证的加密方案

基于离散对数问题和Schnorr算法提出了一个新的有效的认证加密方案,新方案具有以下优点:该方案在不暴露消息明文的情况下,任何第三方都可验证签名的有效性,实现公开验证;降低了计算量和占用带宽;在签名中加入了时间戳,能够有效防止重发密文攻击.     

GSM-R系统的安全策略研究与改进

由于网络结构与用户终端移动性本身的制约,GSM-R本身存在着一些网络安全隐患,本文旨在提出GSM-R系统安全策略的改进方案.文章结合GSM-R系统在铁路上的应用,简要阐述了现有GSM-R系统所采用的安全机制和存在的安全缺陷.针对GSM-R系统采用的单向认证和信息加密的局部性两个方面分别提出了相应的改进方案,即系统的双向认证和端到端加密,并详细描述了认证过程和加密过程.     

数字图像安全技术研究进展

随着数字技术和因特网的飞速发展,图像数据的安全性越来越受到社会的普遍重视.全面分析了数字图像安全需求以及为达到各安全需求的各种安全措施,重点对数字图像加密以及数字图像水印技术的研究现状以发展进行了分析,并对存在的问题以及该领域未来可能的研究方向和研究重点进行了展望.     

桥长调查和桥长公式

根据两次全国公路大中桥孔径设计资料的调查, 对桥孔长度进行了全面分析, 为 《公路工程水文勘测设计规范》制定桥长公式提供参考．     

恶意主机上Mobile Agent安全解决方案

根据非对称加密原理提出了恶意主机上Mobile Agents（MA）的安全解决方案。在该方案中，只有得到许可的主机才能执行MA的代码，交换的数据也要求加密。当MA返回源主机后可根据MA执行过程中的信息判断是否有目标主机对其有恶意行为。分析了恶意主机上MA所受到的安全威胁，并用所提出的方案逐一分析解决了MA所受到的安全威胁。     

Security Policies for Web Service Invocation of Automotive Industry Chain Collaboration Platform

To meet the actual requirements of an automotive industry chain collaboration platform (AICCP), this paper offers several simple but effective security policies based upon the traditional security mechanism of data transfer, including user ID verification with SOAP (simple object access protocol) header, SOAP message encryption with SOAP extension and XML (extensible markup language) file encryption and decryption. Application of these policies to the AICCP for more than one year proves the effectiveness of the data exchange practice between the AICCP and enterprise Intranet.     

蓄电池电压驱动的缸内直喷汽油发动机喷嘴的研究

把喷嘴的线圈分成开启与保持两部分，开启线圈用于快速开启电磁阀，而保持线圈在电磁阀开启之后仅起保持作用，驱动电路使用蓄电池直接驱动，简化了驱动电路，而且避免了电磁噪声的产生，使其可以直接安装在发动机驱动电路中，ECU通过控制开启线圈上电时间来控制喷油量．     

无理数发生器及确定性随机数发生器

计算机密码学的核心在于如何可靠的产生随机数．无理数小数无限展开序列以其不重复的无限不循环特性,非常适合作为一次性随机数发生器使用．在信息安全领域,利用此特性可以产生无限长的确定性随机密钥．文中就无理数的无限不循环小数的特性及其作为二进制的0,1字串的0,1分布情况,进行正规性的满足性证明．给出n＋1√n（n〉1）的通用无理数构造算法,并对其在密码学领域的典型应用,即确定性随机数发生器的应用进行实现算法说明．     

钢框架梁柱端板连接腹板开孔型节点的受力特性

对梁柱端板连接标准型和腹板开孔型节点进行了非线性有限元分析,研究了腹板开孔参数对节点区应力分布、屈服时应力应变发展变化及节点的弹性极限承载力的影响,对不同开孔尺寸节点的力学性能进行了分析比较,探讨了端板厚度、螺栓、开孔参数对端板上应力分布的影响．结果表明,梁柱端板连接腹板开孔型节点的细部构造对其受力影响较大,采用合理的细部构造形式有利于降低应力集中．改善节点的应力分布,使之受力均匀合理．