Specification and Verification for Semi-Structured Data

Tree logic, inherited from ambient logic, is introduced as the formal foundation of related programming language and type systems, In this paper, we introduce recursion into such logic system, which can describe the tree data more dearly and concisely. By making a distinction between proposition and predicate, a concise semantics interpretation for our modal logic is given. We also develop a model checking algorithm for the logic without △ operator. The correctness of the algorithm is shown. Such work can be seen as the basis of the semi-structured data processing language and more flexible type system.     

Password-Based Group Key Agreement Protocol for Client-Server Application

0 IntroductionWith the rapid advances of computer networks , moreand more users are connecting together to exchangelarge amounts of information and share useful resources .However ,the security issue is still a major gating factor fortheir full adoption; mainly due to many malicious adversariesresidingin networked environments will eavesdrop,interceptand modify the transmittedinformation.The client-server model , over past years , has enjoyedsignificant and continually increasing popularity in…     

小世界网络中的相分离和超大磁电阻效应

由于自旋、轨道、电荷和晶格的关联作用,具有超大磁电阻效应的锰氧化物表现出自发的相分离特征和复杂网络的输运特性.小世界网络是介于规则网络与无规网络之间的一种新的网络构形,它能够很好地描述锰氧化物的相分离特征.我们运用蒙特卡罗方法研究了基于小世界网络的一维伊辛自旋链中的磁输运性质,发现小世界关联会导致自发的长程序.随着小世界长程作用的增强,铁磁相的区域扩大,同时体系的磁性相变温度升高.相应的电阻网络模拟显示,在铁磁—顺磁转变温度附近,磁电阻效应有了很大的提高,很好地解释了锰氧化物中的相分离现象与超大磁电阻效应.     

轧机主传动轴断裂事故分析

为分析某热轧厂R2轧机传动轴断裂的原因,对该轧机在典型工况下传动轴受力状况进行了现场试验研究,采用现代设计方法对传动轴进行分析,结果表明,平衡力产生的弯矩造成轴的应力集中而导致断裂。根据此结果对轴的结构进行了改进。     

Sn-基复合氧化物的制备及电化学性能研究

采用一种流变相法制备掺杂B和P非金属元素的SnO复合氧化物（TBP）,对不同温度下热分解得到的产物结构及作为锂二次电池负极材料的电化学性能进行表征。结果表明,以比容量和循环性能折中考虑,500℃热处理试样的电化学性能较好。     

浅析粉煤灰在混凝土施工中的使用

在混凝土中掺入定量的粉煤灰既可降低成本，又可改善混凝土性能。分析了粉煤灰最佳掺量与坍落度、混凝土强度等级、浇筑气温、原材料的关系。     

A Method to Implement Full Anonymous Attestation for Trusted Computing Platform

Trusted computing （TC） technology is brought out by trusted computing group （TCG） to make computing as safe and reliable as people expect. Attestation is one main function specified by TCG, which is the means by which a trusted computer assures a remote computer whose platform is not tampered with. There are two protocols that implement attestation without disclosing the platform＇s real identity, which are Privacy CA-based protocol and direct anonymous attestation （DAA） protocol. However, in the first protocol the privacy CA is the bottleneck and the platform＇s identity will be disclosed if the privacy CA is compromise, while DAA protocol can do profiling when dealing with rogue hardware device. In this paper, we propose a DAA-extended new approach to ensure full anonymous attestation that can not only detect a rogue TPM, but also reveal rogue TPM＇s real identity.     

一种改进的Linux内存分配机制

在对Linux2.4.0中一种新型的内存分配机制－zone分配器进行分析的基础上，针对其中存在的碎片问题提出了一种改进的分配算法和碎片解决方案，即在区中定义一系列子区，每一个子区只用来处理一个类对象的分配，改进后的zone分配器简单、快速、明显减少了内存碎片，提高了分配性能。     

挤压油膜柔性转子系统突加质量的响应特性

针对旋转机械中经常发生折断或丢失一部分旋转质量的现象，分析研究了挤压油膜阻尼器－滑动轴承－柔性转子系统在考虑油膜惯性力的情形下，突加不平衡作用的响应特性。并将其所得的结果与不考虑惯性力情形下的结果进行了比较。研究表明：考虑惯性力后，此转子系统在定转速条件下，突加不平衡质量的响应时间和振幅都减小了。     

中国北方干旱化数据库的建立及问题探讨

文章简述了中国北方干旱化数据库的建立 ,并提出在数据库的建设过程中 ,由于数据源统计单元与时间序列较长而引起的基本问题及其解决方案 .对于不同数据源的基本单元采用面积权重法实现单元的匹配 ,采用解析的方法实现了社会单元、自然单元和信息单元的复合 ;对不同时段行政区划变化、统计标准和统计量纲不统一的问题 ,采用建立标准年份行政区划和统计标准换算的方法加以解决