Research On Items Assignment Method For Automated Sortation System Of Pharmaceutical Logistics Distribution Center

Automated sortation system is widely used in pharmaceutical logistics distribution center, but because pharmaceuticals items are numerous and order structures are complex, how to reasonably assign items, improve equipment sorting efficiency, has been one of the problems to be solved for pharmaceutical logistics distribution center. The thesis researched on items assignment methods, taking an automatically sortation system of a harmaceutical logistics distribution center as an example.Items assignment is to assign all of the items to the automatically sortation system, which decides the selection of quantity of the orders and items sorting parallel degree on the channels, which affected orders sorting time.Reasonable items assignment could raise automatically sortation system sorting efficiency based on no additional cost of equipment.At present, automated sortation systems of pharmaceutical logistics distribution center widely applied are based on wireless digital picking. The research of the thesis is based on wireless digital picking which the characteristic is sorting parallel on Multi-layer and serial on the same layer, combining unique feature of the pharmaceutical logistics distribution center. And this paper analyzes the main factors influencing the sorting efficiency, namely sorting waiting time on the same time and personnel replenishment efficiency. This thesis researchs from two angles of shortening waiting time and improving personnel replenishment efficiency, concludes two methods based on rapid replenishment and replenishment comfortable degree respectively, and provides theoretical guidance for items assignment on an automatically sortation system of pharmaceutical logistics distribution center.First, logistics system methods and theory are used to analyze and study the method of configuring pharmaceutical automated sortation system. According to sorting operation characteristic of the pharmaceutical logistics distribution center, the thesis determines the pharmaceutical sortation system planning factors, sorting unit, operation way, etc.Secondly, this thesis makes a deep analysis to the equipment, system composition, operation process, sorting efficiency of the pharmaceutical automated sortation system. And researched how to shorten sorting waiting time in the same layer under a rapid replenishment mode, puts forward an items assignment method based on items similarity coefficient and using heuristic optimization model of clustering algorithm to solve.To further enhance the paper value of application, this thesis researches the items assignment problem from improving the replenishment comfort degree. And designs replenishment scheme, puts forward the items assignment optimization indexes: distribution of the replenishment of items demands for balanced and the sum of items similarity coefficient in the same layer is minimum, and based on these, the thesis builds multi-objective optimization model and use the best - the worst ant system to slove the problem.Finally, taking items assignment problem for an automated sortation system of pharmaceutical logistics distribution center as an example, the paper testifies the methods to slove items assignment problem are feasibility and validation. Results show that the two methods proposed to slove items assignment problem can shorten the time 11% 25% than traditional experience method and can make the replenishment comfort reach 30%-80%. Distribution center can choose one of the two kinds of methods, in light of the replenishment efficiency of the automated sortation system.