火电厂水务管理软件开发与应用

做好火电厂水务管理工作的前提是建立水平衡监测体系,对系统中各部分的需水量、水质以及排放量、排放水质等参数进行综合考虑,从而确定合理的用水方案。通过火力发电厂水系统划分,确定测量范围和内容,制定完善的统计规则,编制通用型火力发电厂水务管理软件。该软件在水平衡试验的运行检测中,达到了设计的标准,简化很多复杂的计算和烦琐的统计工作,有效的提高了工作效率。     

电网电压不平衡且严重畸变时的软件锁相技术

针对传统软件锁相环（SPLL）在三相电压不平衡且严重畸变条件下不能准确跟踪电网电压的频率和相位的问题。本文提出了一种基于相序解耦（SDR）级联二阶广义积分（SOGI）的新型软件锁相模型,通过SDR和SOGI实现了正负序分离,电压基波提取,以及滤波功能,有效地消除了负序分量、谐波分量对准确获取频率和相位信息的影响。仿真结果表明在三相电压不平衡且严重畸变的条件下,该新型SPLL能够准确地锁定电网电压的频率和相位,从而有效性地验证了新方法的正确性。     

SOE系统输入卡件的设计

事件顺序记录,即SOE（Sequence of Events）系统可以正确、快速地确定事故故障,迅速处理事故,恢复系统的正常运行。SOE系统中输入卡件的设计,包括卡件的组成及软件模块的设计。产品测试表明,系统接收多点数据信息正确,能够及时准确的反映数据采集的实时数值,并提供报警信息。     

自适应二进制算术编码的动态可重构实现研究

针对H.266/VVC视频编码标准下的上下文自适应二进制算术编码器编码速度慢、资源开销大的问题,面向可重构结构依据算法的内在并行特性优化了编码架构,并基于动态可重构阵列处理器设计实现了CABAC编码器常规编码模式下的并行映射方法,阵列结构能够根据编码输入对优化后的算法进行动态重构,在避免专用硬件编码器较高的资源开销情况下利用软件重构的方法实现熵编码过程,保证编码准确性的同时提高了视频数据流编码效率,为此类运算密集型算法的硬件实现提供了更为灵活高效的参考途径。仿真结果表明,映射实现的编码过程中每个编码周期完成5个二进制序列的编码,平均编码效率达到384.13Mbin/s。基于FPGA的测试结果表明,软件重构方法与专用硬件实现的编码器相比,资源开销降低且编码效率提升5.47%,与同类型可重构视频编码结构相比,编码效率提升7.03%。     

Using the cloud to develop applications supporting geo-collaborative Situated Learning

Situated Learning stresses the importance of the context in which learning takes place. It has been therefore frequently associated with informal learning or learning outside the classroom. Cloud technologies can play an important role supporting this type of learning, since it requires ubiquitous computing support, connectivity and access to data across various scenarios: on the field, in the classroom, at home, etc. In this paper we first present the situated learning theory and how we can take advantage of services offered by Cloud Computing to implement computer applications implementing learning activities based on this theory, providing pertinent geographical information and discussion boards. Next we propose a software architecture schema which can be used as a basis for integrating existing cloud services into new applications supporting learning activities. Then we present two examples developed with this approach with its viability and advantages. These are discussed in the concluding chapter.     

Trust assessment of security for e-health systems

The expansive connectivity of emerging information systems has set the stage for pervasive access to healthcare services via e-health systems for selecting the best possible healthcare services. Emerging systems are expected to be highly dynamic open environments connecting diverse number of healthcare services and autonomous entities that are autonomous agents or software applications representing patients. Entities in such dynamic environments may have different security needs from e-health systems raising the challenge of trust computations regarding security. In this research, we proposed a trust assessment model of an e-health service from the viewpoint of an entity. The model contains a comprehensive architecture applicable to different types of entities, and a novel set of trust assessment metrics may be used to assess a specific property of a security system (i.e. partial metrics) or all properties (i.e. total metrics). The simulation based evaluation of proposed model in the context of a Hospital Online Appointment Service has shown that the proposed model provides better trust computation results than existing trust models for e-health systems. Furthermore, the entities are also able to assess the trust even with incomplete security information.     

基于AADL的综合航电分区系统可调度性判定

综合模块化航电(IMA)系统中的分区系统提高了其可靠性和安全性,但在系统设计和实现过程中,应采用各种分析和验证方法确保系统的时间需求得到满足。为此,针对符合ARINC653规范的IMA系统,根据分区系统层级调度的特性,提出一种基于仿真的分区任务集可调度性判定方法。借助Cheddar工具及其自定义调度策略功能,使架构分析和设计语言(AADL)具有对分区系统进行建模的能力,并利用该工具对AADL模型进行仿真以判定系统的可调度性。实例分析结果表明,该方法能自动、准确、快速地进行可调度性判定,并以甘特图的方式绘制任务调度过程,得到直观、详细的结果。     

一种环境感知的仿真服务调度模型

针对传统分布式仿真框架HLA/RTI中动态调度负载平衡较差、执行可靠性较低的问题,提出一种基于环境感知的仿真服务调度模型C3SM。C3SM模型包含总体结构、调度策略和服务部署。总体结构规定各个模块的功能与交互接口,调度策略采用改进的蚁群算法进行仿真服务的动态调度,服务部署采用重叠覆盖部署策略以保证较好的服务可用性和较低的资源消耗。仿真实验结果表明,与传统分布式仿真框架HLA/RTI相比,C3SM模型通过实时获取执行环境的上下文信息,能够获得较优的负载平衡度,且重叠覆盖的仿真服务部署策略使得仿真运行系统的可靠性明显提高。     

一种并行中英文混合多模式匹配算法

针对中英文混合文本的匹配准确性及大规模数据文本的匹配效率等问题,基于经典的线索化完全哈希特里树算法,提出一种并行化的中英文混合多模式文本匹配算法。采用拆分文本降低多模式匹配算法的串行度,进而在拆分出的小文本上并行地执行文本匹配。通过并行化预处理过程,设计新的存储结构。实验结果表明,该算法在保证结果正确的前提下,执行效率高于经典的串行匹配算法,当数据规模达到226个字符时,可以获得8倍以上的加速比。