世妇会IBC电视转播系统设计

本文作者参与了世妇会ＩＢＣ电视转播系统的设计，施工，测试及运行的全部过程，文章详细介绍了系统的总体要求，基本方案，设计及运行，以及由此得出的几点经验。     

Vibration Testing of Intermediate Bulk Containers for Dangerous Goods

Intermediate bulk containers (IBCs) for liquid dangerous goods require a ‘vibration test’ for type approval introduced in the United Nations Recommendations on the transport of dangerous goods. The test has to be performed as a repetitive shock test practically identical to the test procedure previously prescribed by the US Department of Transport. It is conceptually simple but has several drawbacks. The kinetics and dynamics of a bouncing IBC have been investigated by means of simple computational models. With increasing complexity, partially plastic impact, elastodynamic response and the excitation of internal vibrations not directly affected by the bounces can be covered. The latter is a model for the sidewall vibrations. The numerical results show that the control over the specimens' response is only partially defined in the test procedure. Chaotic movements at resonance are possible and must be suppressed by changing the test parameters, which is mostly left to the test engineer. Accordingly, it is not possible to interpret the test results with a sound relation to real transport vibration environment. Experimental results, however, suggest that vibration testing of IBCs improves safety because resonance effects in a frequency range excited by typical transportation loads exist. A more detailed numerical model is necessary for the assessment of the fatigue damage imposed on IBCs by the prescribed or alternative, more realistic test procedures. Copyright © 2011 John Wiley & Sons, Ltd.     

标准模型下高效的异构签密方案

异构签密方案能够为不同安全域之间的数据通信提供机密性和认证性。分析现有的异构签密方案,都是在随机预言模型下可证安全的。基于此,该文提出一个在标准模型下从基于身份的密码到传统公钥设施的签密方案,利用计算Diffie-Hellman问题和判定双线性Diffie-Hellman问题的困难性,对该方案的机密性和不可伪造性进行了证明。通过理论和实验分析,该方案在计算成本和通信成本方面具有更高的效率。     

Contact fault characterisation of complex silicon solar cells: a guideline based on current voltage characteristics and luminescence imaging

Highest efficiency solar cells in industrial and R&D environments are increasingly sensitive to local performance limiting processing faults, which are best characterised by spatially resolved characterisation techniques. This work contains a discussion on the processing faults related to contact resistance and finger interruptions in interdigitated back contact silicon solar cells, which are prime example for a complex cell structure. Using experimental and simulated current–voltage measurements and luminescence images, we explore the strongly non‐linear effect of poor local contact resistances on the global series resistance, fill factor, short circuit current density and efficiency. A good agreement between global and spatially resolved characterisation of faults is found, and potential artefacts are discussed. In conclusion, we present seven cases of contacting faults in interdigitated back contact cells with distinct characteristics that can be identified using a flow chart of experiments. The resulting guideline should assist silicon solar cell manufacturers in localising and quantifying local contacting faults that reduce the cells efficiency in manufacturing of complex solar cells. Copyright © 2015 John Wiley & Sons, Ltd.     

基于身份的网格安全体系结构研究

为了克服PKI证书机制对GSI规模化发展的制约, 本文在分析GSI中证书机制局限性的基础上, 将HIBC引入到GSI中, 使用HIBC签名方案代替GSI中的PKI数字证书签名并进行扩展, 提出一种基于身份的网格安全体系结构IBGSI（ID-based GSI）, 进而给出了结合HIBC方案改进TLS握手协议的方法, 并通过一组协议控制下的实体交互过程定义IBGSI的协议结构. 论文从分层身份结构、认证结构和协议结构三个方面对IBGSI进行了研究, 研究结果表明IBGSI体系结构融合了GSI与IBC的优势, 能够重用GSI的安全服务且便于部署, 并获得IBC轻量、高效的优点.     

浅谈无线网络中的安全技术

该文首先分析了无线通信网络的不安全因素,提出无线网络安全需求,接下来主要描述了基于WPKI和IBC的无线网络安全技术,对各自的工作流程和工作方式进行介绍,希望能够对相关工作的开展有一些参考作用。     

一种基于可信计算平台的无线传感器网络标识密钥更新方法

针对无线传感器网络使用标识密码的密钥更新问题,设计了一种以可信计算平台为密钥生成中心,利用单向函数构造随机数池的高效密钥更新方案,使得传感器节点既能对密钥更新消息进行验证,又不至于引起过多的网络通信。为保证通信密钥的安全性,使用可信计算平台作为密钥生成中心,保证了密钥源头的安全。密钥更新时,利用可信计算平台的特性对其平台配置情况进行验证,来判断其所发出的消息和密钥的真实性与完整性。利用单向函数产生随机数池,一方面使得传感器节点可以验证消息的真实性,另一方面可以抵抗重放攻击。     

基于身份的无线传输层安全握手协议改进方案

现有无线传输层安全(WTLS)协议主要基于数字证书构建,存在通信与计算开销较大、未对服务器证书的有效性进行在线验证等不足。以基于身份的密码体制思想,综合运用基于身份的加密(IBE)、基于身份的签名(IBS)及基于身份的密钥协商(IBAKA)等机制,提出了一种基于身份的密码系统(IBC)的WTLS改进协议。改进协议以身份标识为核心,以传递身份标识代替传递证书,使用IBE、IBS及IBAKA分别完成加密、签名及密钥协商等操作,并在密钥计算中融入了加密者的身份信息,使得密文具有消息源的可认证性。对改进协议的安全性及效率的分析表明,改进协议在确保安全的前提下降低了通信开销。     

一种新型稀疏Ad Hoc网络消息签名方案

针对稀疏Ad Hoc网络的易断易延时特性,采用基于身份的密码体制和椭圆曲线双线性对,提出一种新的稀疏Ad Hoc网络消息签名方案,并对方案的安全性和性能进行了分析。该方案可以解决第三方密钥托管带来的签名伪造问题,限制稀疏Ad Hoc网络中节点私钥泄密带来的伪造消息签名的影响,在保证安全性的前提下,有效减少密钥长度、签名长度与签名的计算量,降低了对网络通信带宽和节点存储、计算能力的要求,符合稀疏Ad Hoc网络的签名需求。     

Grid authentication from identity-based cryptography without random oracles

As a critical component of grid security, secure and efficient grid authentication needs to be well addressed. However, the most widely accepted and applied grid authentication is based on public key infrastructure （PKI） and X.509 certificates, which make the system have low processing efficiency and poor anti-attack capability. To accommodate the challenge of grid authentication, this article aims at designing a secure and efficient method for grid authentication by employing identity-based cryptography （IBC）. Motivated by a recently proposed secure and efficient identity-based encryption （IBE） scheme without random oracles, an identity-based signature （IBS） scheme is first proposed for the generation of private key during grid authentication. Based on the proposed IBS and the former IBE schemes, the structure of a novel grid authentication model is given, followed by a grid authentication protocol described in detail. According to the theoretical analysis of the model and the protocol, it can be argued that the new system has improved both the security and efficiency of the grid authentication when compared with the traditional PKI-based and some current IBC-based models.