Considering that the vehicle routing problem （VRP） with many extended features is widely used in actual life, such as multi-depot, heterogeneous types of vehicles, customer service priority and time windows etc., a ...Considering that the vehicle routing problem （VRP） with many extended features is widely used in actual life, such as multi-depot, heterogeneous types of vehicles, customer service priority and time windows etc., a mathematical model for multi-depot heterogeneous vehicle routing problem with soft time windows （MDHVRPSTW） is established. An improved ant colony optimization （IACO） is proposed for solving this model. First, MDHVRPSTW is transferred into different groups according to the nearest principle, and then the initial route is constructed by the scanning algorithm （SA）. Secondly, genetic operators are introduced, and crossover probability and mutation probability are adaptively adjusted in order to improve the global search ability of the algorithm. Moreover, the smooth mechanism is used to improve the performance of the ant colony optimization （ACO）. Finally, the 3-opt strategy is used to improve the local search ability. The proposed IACO was tested on three new instances that were generated randomly. The experimental results show that IACO is superior to the other three existing algorithms in terms of convergence speed and solution quality. Thus, the proposed method is effective and feasible, and the proposed model is meaningful.展开更多
由于机型体积小,安装、操作方便和分散控制等特点,风机盘管(Fan Coil Unit,FCU)空调系统在办公楼、宾馆和公寓等建筑场所得到了广泛应用。然而,其主要设备-FCU具有惯性和较大时间滞后等动态特性,传统控制方式,如整数阶PID方式会导致室...由于机型体积小,安装、操作方便和分散控制等特点,风机盘管(Fan Coil Unit,FCU)空调系统在办公楼、宾馆和公寓等建筑场所得到了广泛应用。然而,其主要设备-FCU具有惯性和较大时间滞后等动态特性,传统控制方式,如整数阶PID方式会导致室温稳态误差和超调量较大,调节时间长等问题。鉴于此,提出FCU的室温分数阶PID(PIλDμ)控制器参数整定新算法及其控制系统构建的设计思路。首先,结合空调工艺的相关要求和分数阶控制技术,分别对FCU作用下的室内温度对象、室温测量变送器、FCU的送风单元、冷却/加热单元和室温PIλDμ控制器(Indoor Temperature Fractional Order Proportional Integral Derivative Controller,IT-FOPIDC)进行建模。其次,基于改进的蚁群优化算法(Improved Ant Colony Optimization Algorithm,IACOA)对该IT-FOPIDC的5个控制参数进行整定,获取其最佳值。最后,借助Matlab工具,对FCU作用下的空调房间室温PIλDμ调节系统进行组态和数值模拟其控制效果。结果表明,该室温PIλDμ调节系统在理论上是可行的,且室温控制效果明显优于Ziegler-Nichols(Z-N)整定法和ACOA算法的室温整数阶PID控制系统。展开更多
基金The National Natural Science Foundation of China(No.61074147)the Natural Science Foundation of Guangdong Province(No.S2011010005059)+2 种基金the Foundation of Enterprise-University-Research Institute Cooperation from Guangdong Province and Ministry of Education of China(No.2012B091000171,2011B090400460)the Science and Technology Program of Guangdong Province(No.2012B050600028)the Science and Technology Program of Huadu District,Guangzhou(No.HD14ZD001)
文摘Considering that the vehicle routing problem （VRP） with many extended features is widely used in actual life, such as multi-depot, heterogeneous types of vehicles, customer service priority and time windows etc., a mathematical model for multi-depot heterogeneous vehicle routing problem with soft time windows （MDHVRPSTW） is established. An improved ant colony optimization （IACO） is proposed for solving this model. First, MDHVRPSTW is transferred into different groups according to the nearest principle, and then the initial route is constructed by the scanning algorithm （SA）. Secondly, genetic operators are introduced, and crossover probability and mutation probability are adaptively adjusted in order to improve the global search ability of the algorithm. Moreover, the smooth mechanism is used to improve the performance of the ant colony optimization （ACO）. Finally, the 3-opt strategy is used to improve the local search ability. The proposed IACO was tested on three new instances that were generated randomly. The experimental results show that IACO is superior to the other three existing algorithms in terms of convergence speed and solution quality. Thus, the proposed method is effective and feasible, and the proposed model is meaningful.
文摘由于机型体积小,安装、操作方便和分散控制等特点,风机盘管(Fan Coil Unit,FCU)空调系统在办公楼、宾馆和公寓等建筑场所得到了广泛应用。然而,其主要设备-FCU具有惯性和较大时间滞后等动态特性,传统控制方式,如整数阶PID方式会导致室温稳态误差和超调量较大,调节时间长等问题。鉴于此,提出FCU的室温分数阶PID(PIλDμ)控制器参数整定新算法及其控制系统构建的设计思路。首先,结合空调工艺的相关要求和分数阶控制技术,分别对FCU作用下的室内温度对象、室温测量变送器、FCU的送风单元、冷却/加热单元和室温PIλDμ控制器(Indoor Temperature Fractional Order Proportional Integral Derivative Controller,IT-FOPIDC)进行建模。其次,基于改进的蚁群优化算法(Improved Ant Colony Optimization Algorithm,IACOA)对该IT-FOPIDC的5个控制参数进行整定,获取其最佳值。最后,借助Matlab工具,对FCU作用下的空调房间室温PIλDμ调节系统进行组态和数值模拟其控制效果。结果表明,该室温PIλDμ调节系统在理论上是可行的,且室温控制效果明显优于Ziegler-Nichols(Z-N)整定法和ACOA算法的室温整数阶PID控制系统。
