An improved bacterial foraging algorithm for combined static/dynamic environmental economic dispatch

Economic dispatch is carried out at the energy control center to find out the optimal output of thermal generating units such that power balance criterion is met, unit operating limits are satisfied and the fuel cost is minimized. With growing environmental awareness and strict government regulations throughout the world, it has become essential to optimize not only the total fuel cost but also the harmful emissions, both, under static as well as dynamic conditions. The static environment economic dispatch finds the optimal output of generating units for a fixed load demand at a given time, while the dynamic environmental economic dispatch schedules the output of online generators with changing power demands over a certain time period (normally one day) so as to minimize these two conflicting objectives, simultaneously. In this paper, the price penalty factor approach is employed for simultaneous minimization of cost and emission. The generator ramp rate constraints, non-convex and discontinuous nature of cost function and the large number of generators in practical power plants, make this problem very difficult to solve. Here, a fuzzy ranking approach is employed to identify the solution which offers the best compromise between cost and emission objectives.     

Environmental economic dispatch in multi-area power system employing improved differential evolution with fuzzy selection

In a deregulated multi-area electrical power system the objective is to determine the most economical generation dispatch strategy that could satisfy the area load demands, the tie-line limits and other operating constraints. Usually, economic dispatch (ED) deals only with the cost minimization, but minimization of emission content has also become an equally important concern due to the mandatory requirement of pollution reduction for environmental protection. Environmental economic dispatch (EED) is a complex multi-objective optimization (MOO) problem with conflicting goals. Normally a fuzzy ranking is employed to rank the large number of Pareto solutions obtained after solving a MOO problem. But in this paper the preference of the decision maker (DM) is used to guide the search and to select the population for the next generation. An improved differential evolution (DE) method is proposed where the selection operation is modified to reduce the complexity of multi-attribute decision making with the help of a fuzzy framework. Solutions are assigned a fuzzy rank on the basis of their level of satisfaction for different objectives before the population selection and then the fuzzy rank is used to select and pass on better solutions to the next generation. A well distributed Pareto-front is obtained which presents a large number of alternate trade-off solutions for the power system operator. A momentum operation is also included to prevent stagnation and to create Pareto diversity. Studies are carried out on three test cases and results obtained are found to be better than some previous literature.     

ARAIM可用性预测系统的设计与实现

随着全球导航卫星系统空间星座的增多以及双频技术的发展,用于航路阶段的常规接收机自主完好性监测算法不能满足LPV-200进近对完好性的要求,因此,出现应用于进近阶段的高级接收机自主完好性监测(ARAIM)技术。针对 LPV-200进近,基于对垂直保护限值的理论分析,研究ARAIM可用性预测算法,并设计ARAIM瞬时可用性预测系统。仿真结果表明,该系统能满足LPV-200进近对完好性的要求,在中国区域内,当可用性设置为99.9%时,ARAIM预测算法的覆盖率可达100%。     

多星座全球导航卫星系统完整性分析

在未来多星座双频情况下,对全球导航卫星系统提供的全球服务的完整性进行仿真分析,设计多星座的模拟环境,采用奇偶向量法进行完整性计算,从而获得全球VPL的分布情况。仿真实验结果表明,与现有全球定位系统提供的标准定位服务相比,该系统提供的服务的完整性更高,能够达到民航LPV-200级别的完整性要求。     

基于MRDS的清洁机器人室内路径规划算法的仿真实现

针对目前室内清洁机器人的路径规划算法理论研究较多,而难以应用于实践的问题,建立了清洁机器人相对定位的数学模型,通过使用清洁机器人的迂回式路径规划、回字形路径规划、包围式路径规划和启发式路径规划算法进行了研究,分析了路径规划算法的具体实现过程.利用微软机器人开发平台（MRDS）,使用可视化编程语言（VPL）,对4种路径规划算法进行仿真实验.对启发式路径规划中激光测距仪的返回数据进行了分析,将单位时间内各路径规划算法的转弯角度作为评价算法优劣的标准,比较了各路径规划算法的优缺点.研究结果表明,启发式路径规划中,清洁机器人能够根据当前的环境信息选择最佳路径,相同时间内所用转弯角度最少,该算法优于其他算法,具有一定的推广价值.     

一种支持VPL的制造执行系统的体系结构

在制造执行系统(Manufacturing Execution Systems，MES）中实现VPL(Virtual Production Line)可以较好地平衡现代制造系统对生产效率和灵活性的需求。提出了基于ARC模型（Asent，Role，Character)的车间-工艺协作-资源(SVR)、支持VPL实现的多代理MES体系结构。给出了一个车间订单处理实例，说明了该系统实现高度灵活性的特点。     

长输油气管道激光焊接技术

分析了熔化极气体保护焊与激光焊在管道焊接中的优缺点.以德国VIETZ公司的管道激光焊接系统VPL为重点,介绍了高能光纤激光器焊接系统的设备架和空调房的组成;评定了其焊接工艺,实验结果表明,焊缝成形窄,X射线检测无裂纹和气孔,管道错边量在允许范围内时,焊缝成形也较好.展望了激光焊接技术在管道焊接中尤其X70管线钢时的应用前景.     

基于视图的访问控制语言VPL及其应用

CORBA中间件的安全管理是一个烦琐而重要的工作。本文针对CORBA安全服务规范在安全管理方面的不足,介绍了一种新的访问控制管理语言,即视图策略语言(VPL),并用一个具体实例说明了VPL如何对访问控制策略进行静态和动态管理,体现了VPL在策略管理方面带来的好处。     

分布式对象访问控制的UML建模

讨论如何扩充UML图素,为系统对象安全访问控制建模,使安全建模融入系统建模的各个阶段,使用视图策略描述语言VPL形式化描述安全模型,探讨了安全策略由VPL描述向通用的扩展的访问控制语言XACML描述的映射.     

基于RFID的生产线监控技术与应用

针对离散制造企业数据采集手段落后,生产线实时监控能力弱的问题,研究和实现了基于RFID技术的生产线可视化监控系统.给出了生产线可视化和生产过程控制的技术实现方法,通过实际应用表明,该方法提高了企业的生产效率和产品质量,取得了较为明显的经济效益.