Research on Fault Tolerant Scheduling Algorithms of Web Cluster Based on Probability

Aiming at the soft real time fault tolerant demand of critical web applications at present, such as E-commerce, a new fault tolerant scheduling algorithm based on probability is proposed. ““““““““Ib achieve fault tolerant scheduling, the primary/slave backup technology is applied on the basis of task‘s self similar accessing characteristics, when the primary task completed successfully, the resources allocated for the slave task are reclaimed, thus advancing system‘s efficiency. Experimental results demonstrate on the premise of satisfying system‘s certain fault tolerant probability, task‘s schedulabilistic probability is improved, especially, the higher task‘s self similar degree is, the more obviously the utilization of system resources is enhanced.     

Turbo-Based DNW Algorithm for Compressed Video in VLC Domain

In order to improve the robustness of the differential number watermarking (DNW) algorithm proposed by us before, we proposed turbo-based DNW (TDNW) in which the turbo code was employed in the DNW algorithm. The turbo code was used to encode the message prior to watermark embedding and decode the watermark posterior to watermark detection. From the analysis and experiments, the following conclusion could be drawn. The T-DNW algorithm has little higher computational complexity than DNW. And both algorithms have the same performance ;,n terms of watermark visual quality impact. Furthermore, the TDNW algorithm is much more robust against some common attack than DNW. Ahhough the TDNW algorithm sacrifices a half payload, we think the achievements are encouraging.     

基于实时分布式计算机系统的容错技术研究

目的为研制适应第四代飞机高度综合化、模块化、高可靠性的航空电子系统的计算平台。方法提出了分层容错管理策略。结果由系统、分系统和模块构成三级容错管理策略;由故障监控程序负责故障的监控和确认,并将确认的故障交由故障管理程序处理;由故障管理程序根据蓝图定义完成重构;重构通过逻辑功能到物理资源的不同映射方式实现;给出了这些过程的实例。结论容错功能的实现必须以保证强实时系统的确定性为前提。     

OPC技术在焦化厂监控系统中的应用

基于对OPC技术的剖析,结合焦化厂的实际工程,介绍了用VB开发OPC客户端的步骤和关键技术,并将OPC与Intemet结合,实现了网络监控。     

洗消车虚拟作战仿真训练系统的设计与实现

给出了洗消虚拟作战仿真训练系统的设计与实现思路,完成了洗消车单机训练分系统的开发,完成了组网协同虚拟作战仿真训练。介绍了系统的构成及激光三维定位系统、可视数据库建模、网络通信、特殊模块等几个关键技术。实践结果表明,该系统可代替实装完成技术、战术训练,在实际应用中产生了显著的军事、经济效益。     

基于可编程图形处理器的实时景深模拟

一幅具有景深效果的图，其显著特征是图像部分清晰部分模糊。基于这一特点，在景深的计算机仿真中，首先由计算机对三维场景成像，并将该场景存储为纹理，此纹理为清晰的场景纹理。成像时通过顶点编程，于α通道中存储了物体距离聚焦面的深度信息。然后对场景纹理进行多次均值滤波生成模糊的场景纹理，最后以清晰场景纹理的α值为插值系数将两幅纹理进行融合而模拟出景深效果。算法充分利用了图形处理器（GPU）的多纹理技术和可编程性，将运算从CPU转移至GPU，很好地仿真了景深效果，且满足实时性要求，可应用于虚拟现实系统。     

基于可视化仿真的水电工程施工进度分析与控制研究

对基于可视化动态仿真的水电工程施工进度分析与控制进行了研究,提出了基于GIS的施工进度可视化动态仿真方法,实现了施工进度仿真建模、计算及结果的可视化;提出了结合柔性网络计划技术的进度分析与优化方法,包括工期分析及资源优化,在此基础上提出了基于可视化动态仿真的施工进度实时管理与控制方法;进行了实例分析,其成果在工程施工进度管理当中的成功应用表明所提方法具有可行性和优越性.     

An Efficient Secure Real-Time Concurrency Control Protocol

0 IntroductionThe real-ti me database system(RTDBS) is usually ap-pliedto the safety-critical applications .Inthese applica-tions,besides the ti ming constraints ,it is essential to preventunlawful information flows between different transactions .The traditional real-ti me concurrency protocols such as two-phase locking high priority (2PL-HP)[1], priority ceiling(PC)[2], OPT-WAIT[3], OPT-SACRIFICE[4], etc ., con-centrate on how to mini mize the missing deadlines ratio oftransactio…     

物流公共实时基础数据平台设计

物流公共实时基础数据平台已成为物流业发展的迫切需要。在分析平台建设可行性的基础上，对物流公 共实时基础数据平台的方案进行了设计，包括平台的目标、作用、基本功能、数据种类、系统结构和关键子系统，以 满足现有物流活动参与各方对信息共享的需求。     

基于Matlab的实时模糊控制系统的研发

研制出一种低成本、高可靠性和高稳定性倒立摆硬件系统,同时提出一种专家模糊控制策略以及基于Matlab的实时控制途径。采用模糊组合变量来减少模糊规则数,并根据摆角来选择不同模糊规则库从而提高控制性能。用Matlab实现的控制算法在对倒立摆的实验中表现出很好的实时控制性能。