The multi-compartment electric vehicle routing problem(EVRP)with soft time window and multiple charging types(MCEVRP-STW&MCT)is studied,in which electric multi-compartment vehicles that are environmentally friendl...The multi-compartment electric vehicle routing problem(EVRP)with soft time window and multiple charging types(MCEVRP-STW&MCT)is studied,in which electric multi-compartment vehicles that are environmentally friendly but need to be recharged in course of transport process,are employed.A mathematical model for this optimization problem is established with the objective of minimizing the function composed of vehicle cost,distribution cost,time window penalty cost and charging service cost.To solve the problem,an estimation of the distribution algorithm based on Lévy flight(EDA-LF)is proposed to perform a local search at each iteration to prevent the algorithm from falling into local optimum.Experimental results demonstrate that the EDA-LF algorithm can find better solutions and has stronger robustness than the basic EDA algorithm.In addition,when comparing with existing algorithms,the result shows that the EDA-LF can often get better solutions in a relatively short time when solving medium and large-scale instances.Further experiments show that using electric multi-compartment vehicles to deliver incompatible products can produce better results than using traditional fuel vehicles.展开更多
Problem solving is an important skill for a computer scientist.Mindstorm based robots have been used previously,for teaching programming to computing and engineering students here we look at problem solving.These appr...Problem solving is an important skill for a computer scientist.Mindstorm based robots have been used previously,for teaching programming to computing and engineering students here we look at problem solving.These approaches focus upon the development of problem solving skills and not on learning a new programming language from the outset.Therefore,initially,any programming is kept simple with the minimum of commands,with 'objects' unknowingly used,as these are later introduced/learnt during the programming stage of the computing module.This work suggests that using LEGO robots within the teaching of problem solving and the resulting java GUI emulation has some benefits for the students when learning to program.展开更多
基金supported by the National Natural Science Foundation of China(71571076)the National Key R&D Program for the 13th-Five-Year-Plan of China(2018YFF0300301).
文摘The multi-compartment electric vehicle routing problem(EVRP)with soft time window and multiple charging types(MCEVRP-STW&MCT)is studied,in which electric multi-compartment vehicles that are environmentally friendly but need to be recharged in course of transport process,are employed.A mathematical model for this optimization problem is established with the objective of minimizing the function composed of vehicle cost,distribution cost,time window penalty cost and charging service cost.To solve the problem,an estimation of the distribution algorithm based on Lévy flight(EDA-LF)is proposed to perform a local search at each iteration to prevent the algorithm from falling into local optimum.Experimental results demonstrate that the EDA-LF algorithm can find better solutions and has stronger robustness than the basic EDA algorithm.In addition,when comparing with existing algorithms,the result shows that the EDA-LF can often get better solutions in a relatively short time when solving medium and large-scale instances.Further experiments show that using electric multi-compartment vehicles to deliver incompatible products can produce better results than using traditional fuel vehicles.
文摘Problem solving is an important skill for a computer scientist.Mindstorm based robots have been used previously,for teaching programming to computing and engineering students here we look at problem solving.These approaches focus upon the development of problem solving skills and not on learning a new programming language from the outset.Therefore,initially,any programming is kept simple with the minimum of commands,with 'objects' unknowingly used,as these are later introduced/learnt during the programming stage of the computing module.This work suggests that using LEGO robots within the teaching of problem solving and the resulting java GUI emulation has some benefits for the students when learning to program.
