覆盖多播节点失效检测的分布式算法的改进

覆盖多播在端系统间构建数据分发树．由于端系统随意地加入或退出多播组,其可靠性不如路由器．当分发树中的非叶节点退出或者节点失效时,其下游节点将受到影响．低代价而快速的节点失效检测能降低由于服务间断所带来的影响,同时也为后续的恢复工作提供一个良好的基础．在分析相关工作的基础上,提出了一种改进的节点失效检测机制,它能够兼顾节点失效检测时间和额外消息负载两个性能指标．     

基于分布式防火墙的高校校园网信息安全建设方案

对高校校园网使用中出现的安全问题,以及传统防火墙技术的不足之处进行了初步分析,并将分布式防火墙应用于校园网建设,设计了一个基于分布式防火墙的高校校园网信息安全解决方案。     

基于．NET的社区医疗健康档案系统设计与实现

探讨了社区医疗健康档案管理系统的关键技术,并利用面向对象的体系结构,构建了一个轻量级、低技术风险的面向组件的安全体系结构模型,设计了一个基于．NET平台的MVC通用开发框架,实现了高效的web开发。     

分布式认知视域下的课堂教学质量评估模式探析

从分布式认知角度,分析了教学效果与教师、学生、组织、学校、社会等多层面的关系。采用模糊综合评价法,对影响课堂教学效果的因素、构成进行实证研究,提出了一套实用性和操作性较强的评估模式。     

基于．NET Remoting三层分布式信息管理系统的设计与实现

以一个房地产中介管理系统设计为背景,探讨了基于．NET Remoting三层分布式的信息管理系统设计的过程和相关思路,说明了使用Remoting技术可以非常便捷地构建分布式的信息管理系统。     

(Un)Critical times? Situating distributed leadership in the field

It is time to situate distributed leadership as a critical conceptualisation of school leadership; its popularisation has generally preceded conceptual and empirical development. Over the last 10 years distributed leadership has often been presented as a new construct of school leadership, though critique against education policy reforms and conceptual and historical links to the wider leadership field have generally been underemphasised. The theorisation and research of distributed leadership is currently situated at a critical point in its development; it is at the ‘crossroads’ of where it could dominantly be situated in the field of school leadership. A review of the literature and research suggests that distributed leadership is tending towards an uncritical position that is decoupled from critique of past and present education reforms and predominantly silent on how power relations at the local school level shape leadership activity.     

Public service reform in education: why is progress so slow?

This case study examines why public‐sector reform in education often fails to deliver expected performance gains. Longitudinal evidence from a secondary comprehensive located in a former coalfield is used to identify constraints that frustrate government policies. Although the head and senior staff at Norcross School adopted transformational, distributed modes of leadership and implemented a rigorous target‐setting regime, the expected increase in effectiveness has not materialised. This disappointment is explained in relation to the flawed assumptions of the result‐driven effectiveness agenda, the resistance arising from continuing structural inequalities in society, and the hyperactive complexity of New Labour’s approach to managing public services. The study concludes that as the assessment regime in England provides an unreliable picture of student progress, there is no stable basis for judging the success of reform, particularly when perceived improvements in student experience are qualitative in nature.     

Application of developed Grid-GA distributed hydrologic model in semi-humid and semi-arid basin

A grid and Green-Ampt based(Grid-GA)distributed hydrologic physical model was developed for flood simulation and forecasting in semi-humid and semi-arid basin. Based on topographical information of each grid cell extracted from the digital elevation model (DEM) and Green-Ampt infiltration method, the Grid-GA model takes into consideration the redistribution of water content, and consists of vegetation and root interception, evapotranspiration, runoff generation via the excess infiltration mechanism, runoff concentration, and flow routing. The downslope redistribution of soil moisture is explicitly calculated on a grid basis, and water exchange among grids within runoff routing along the river drainage networks is taken into consideration. The proposed model and Xin’anjiang model were applied to the upper Lushi basin in the Luohe River, a tributary of the Yellow River, with an area of 4 716 km2 for flood simulation. Results show that both models perform well in flood simulation and can be used for flood forecasting in semi-humid and semi-arid region.     

基于Windows CE构建嵌入式Web Services

在嵌入设备之间使用Web Services可以解决分布嵌入系统之间协同工作的问题．介绍了在Windows CE上构建嵌入式Web Services的基本框架,给出了3个实现方案,并对方案进行分析,为嵌入应用上构建Web Services提供一些设计参考．     

微型冷热电联产系统动力装置的参数优化

建立了内燃机的通用数学模型,提出了内燃机的运行经济区.得出了改装后的LJ276M型内燃机的数学模型,并界定了此内燃机的运行经济区的边界范围,分析了此内燃机的运行优化曲线和最佳运行工况点.针对动力系统的冷热电、热电和供电3种操作模式,分别建立了能量转换数学模型,优化了动力装置的内燃机/变速箱传送比ies、电动机/变速箱传送比ims和电动机/内燃机传送比ime.结果表明：在冷热电模式下,ies和ims的优化值分别为2.9和1;在热电模式下,当动力系统需求负荷小于内燃机运行经济区的下限值时,ime取1,而当动力系统需求负荷超过内燃机运行经济区的下限值时,ime取0.85;在供电模式下,ims的最优值取2.5.