Towards Cross Docking System Model Simulation Optimization Through The Use Of RSM

Logistic system is a Complicated Discrete Event System.As far as the complicated logistics system design concern,Simulation technology not only provides optimal combination of technical and economic,but also a straightforward analysis tool. However,instead of an optimization method,simulation model which is exclusively a sampling simulation should be amalgamated with optimization methods.Simulation optimization is defined as objective optimization researches which studied on input and output characteristic can lead to optimal input quantity based on optimization algorithms through the use of simulation.Logistic scheduling problems employing in simulation optimization become a new focus in the field of logistic researches.This paper encompassed on the transport strategies of Cross-docking distribution system using simulation optimization method Which objective is to simultaneously minimize the operating time and maximize the throughout capacity of the CD.Therefore,this paper can be divided into two parts.(1) Established a CD simulation model.Hitherto,Most of the scholars still analyzed Cross docking system employed with Analytical Method and no the example of use simulation yet.This dissertation applied simulation in CD which can present the whole process of CD characteristics clearly.For this,the author analyzed the methods, strategies,procedures and compared and selected suitable simulation tools.Then introduced the functions,components and simulation steps of Flexsim in details. Through the investigation of processes,styles,tactics and application of CD,developed a CD receiving dock and shipping dock two-phase queue system model.Further, according to the simulation procedures above,accomplished the setting of simulation layout,object parameter,programs of the two-phase Queue system.At last,compiled, debugger and ran the simulation model.(2) Simulation optimization based on RSM.Currently,the popular methods studied on Logistic system are still Heuristic algorithm.In the light of the features of logistics system,this dissertation applied with the Response Surface Methodology and developed the multiple response problems successfully.Based on the results of Flexsim statistical Standard Output Report,showed the possibility of combination of RSM and Flexsim. Chose operation time and throughout as response variables affected by five factors consist of vehicles speed,load,etc.Designed a rotatable central composite design RSM experiment.Simulation experiments are run to produce the responses data and estimate the response surface of the model.After this,the most important factors will be detected and the optimal operating level can be determined.Moreover,the results will be verified in simulation model.The conclusions:Some useful results can be found through the combination RSM with Deterministic Simulation.Compared with other algorithms,Logistics system can comprehensively be characterzie by simulation model.Then,simulation results can be easily analyzed and optimized while using RSM which takes the random factors and errors into account.Moreover,RSM no need to list all of the restrictions but analyze, optimize and verify the system more plainly.