Real coded genetic algorithm for stochastic hydrothermal generation scheduling

The intent of this paper is to schedule short-term hydrothermal system probabilistically considering stochastic operating cost curves for thermal power generation units and uncertainties in load demand and reservoir water inflows. Therefore, the stochastic multi-objective hydrothermal generation scheduling problem is formulated with explicit recognition of uncertainties in the system production cost coefficients and system load, which are treated as random variable. Fuzzy methodology has been exploited for solving a decision making problem involving multiplicity of objectives and selection criterion for best compromised solution. A real-coded genetic algorithm with arithmetic-average-bound-blend crossover and wavelet mutation operator is applied to solve short-term variable-head hydrothermal scheduling problem. Initial feasible solution has been obtained by implementing the random heuristic search. The search is performed within the operating generation limits. Equality constraints that satisfy the demand during each time interval are considered by introducing a slack thermal generating unit for each time interval. Whereas the equality constraint which satisfies the consumption of available water to its full extent for the whole scheduling period is considered by introducing slack hydro generating unit for a particular time interval. Operating limit violation by slack hydro and slack thermal generating unit is taken care using exterior penalty method. The effectiveness of the proposed method is demonstrated on two sample systems.     

交换机过载控制机理Petri网模型的仿真求解方法

通过建立数字交换机过载控制机理的广义随机Petri网模型并基于马氏理论求解,可以有效地分析系统的控制特性,但这种方法对于变迁时延为非负指数分布就比较困难.鉴于此,本文提出用仿真方法求解,利用GPSS仿真对两种常用过载控制机理的广义随机Petri网模型进行了分析,找出了GPSS框图与Petri网模型之间的对应关系,得出了系统性能的仿真分析结果,与理论分析结果相对照,结论是一致的.     

基于Petri网的一种实时计划调度方法

基于实际生产环境中制造系统经常受外部随机事件影响，利用可分解Petri网把整个系统分解成若干个模块，然后对其中的部分模块进行短期的计划调度，使得变更后的生产尽可能和预先计划相一致，并给出了基于关键路径的调度算法，这样既可达到对外部事件作出快速反应的目的，又提供了较优的调度策略。     

基于增广自控网的路灯故障检测系统

用带禁止/容许弧的自控网构建一类路灯故障检测系统模型,此系统模型适用于描述对按线性编号的故障路灯设备进行检测的过程,能够准确的检测出多个故障路灯。系统模型采用应答方式的工作原理。最后,用可达标识和关联矩阵对模型进行分析、验证。     

电子商务系统主体行为的描述与分析

电子商务系统的主体行为对整个交易的安全非常重要。本文应用标注Petri网模拟技术,建立了电子商务系统中主体行为模型,解决了主体的责任分析、证据收集等与安全性有关的问题。     

非线性量化因子模糊控制器及其应用

针对被控系统的随机动态过程,选取系统中的误差与误差变量,采用二者所集成的复合函数实现对系统的最优控制.同时,应用此复合函数设计了包含非线性量化因子的模糊控制算法.采用此模糊控制算法的仿真结果表明,此种方法不仅便于实现,而且与传统的控制方法相比具有较好的控制效果.     

社会关系网络密度对创新扩散的影响

从微观个体角度研究创新扩散是近年来创新扩散颁域的一个重要研究方向,本文运用复杂网络工具来精细刻画个体的微观结构,并以此研究了社会关系网络密度对创新扩散的影响.通过对原有阈值模型进行网络化扩展,结合创新扩散的两个基本渠道--传媒和口头交流.建立了基于复杂网络的随机阙值模型,利用计算机仿真模拟,测试了不同社会关系网络密度下的创新扩散程度,指出社会关系网络密度对创新扩散的影响取决于消费者对传媒网争社会关系网的依赖程度.     

可达性与状态方程可满足性等价的两个Petri网子类

可达性是Petri网最基本最重要的动态性质之一,但一般Petri网的可达性判定问题至少具有指数空间复杂度,且目前尚无有效的判定算法。不过,存在某些Petri网子类,其可达性判定问题要相对简单,寻找这样的Petri网子类具有重要意义。为此,提出极小陷阱回路网与后向回路网的概念,并证明了初始标识下不含空极小回路的这两个Petri网子类,其可达性判定问题等价于状态方程的可满足性问题。     

INTELLIGENT SIMULATION FOR ALTERNATIVES COMPARISON AND APPLICATION TO AIR TRAFFIC MANAGEMENT

1.Introduction Computer simulation technology has matured over the past decade and is now commonly used to evaluate large-scale real systems with complex stochastic behavior.Simulation allows one to more accurately specify a system through the use of logically complex,and often non-algebraic,variables and constraints.This capability compliments the inherent limitation of traditional optimization.However,the added flexibility often creates models that are computationally intractable.The effici…