The Model Of Closed-loop Logistics And Its Algorithm

Closed-loop logistics network contains two aspects: one is the forward logistics of the product from the factory to the sale station and then delivery to the customer area,the second is reverse logistics of recycle products shipped back from the customer area to the sale station then transport to factory.In the practical life,the question of closed loop integrated logistics network is very common,especially in aspect of product transportation,Therefore the scholars is glad to study the deliberation object.This paper researched the problem from the following four aspects.The first,based on uncertainty theory,uncertain closed-loop logistics network is proposed in the expectation and variance of the model.Because of the mean-variance criteria is the balancing act of investors between yield and risk.So that investors need to consider the least expected total cost.At the same time,they also need to make the part of the cost variance as small as possible.Firstly,this paper assumes that equipment construction costs,customer demand and product recovery rate has uncertainty distribution of uncertain variable,and establishes a model of closed-loop logistics network with variance constraint and the smallest expected total cost.Then,the model is transferred to a classical model based on knowledge of uncertainty theory,and the effectiveness of the proposed model is verified by an existing classic algorithms.The second,the uncertain closed-loop logistics network ?-pessimistic value measure constraint model is proposed based on uncertainty theory.In order to guarantee the validity of the model,for the uncertain variables,in addition to using the expected value,you can also use ?-pessimistic value to measure.That is to say uncertain variables to ? measure at least less than or equal to the ? negative value.So we came up with the uncertain closed-loop logistics network ?-pessimistic value measure constraint model,then studied the properties of the model.The third,the measure of uncertain random closed-loop logistics network constraint model and algorithm is proposed based on chance theory.Based on the chance theory,the paper builds a new closed-loop integrated logistics network model.It is called the measure-constraint model of uncertain random closed-loop logistics.The transportation cost of unit from the factory to the store is a random variable with probability distribution function,the transportation cost of unit from the customer to the store and the demand of customer are uncertain variables with uncertainty distribution and the objective is to minimize the expected total cost of the whole logistics.Its constrain is the measure of customer demands and total cost and the balance between production and sale.The properties of the model in special uncertainty distribution are given.The specific form of equal to primary model is gained.The using the given algorithm for verification.The forth one is the based on the new chance theory,chance-constraint model of uncertain random closed-loop logistics and its algorithms are studied.Based on the chance theory,the paper builds a new closed-loop integrated logistics network model.It is called the chance-constraint model of uncertain random closed-loop logistics and the objective is to minimize the expected total cost of the whole logistics.Its constrain is the chance of customer demands and total cost and the balance between production and sale.The properties of the model in special uncertainty distribution are given.An approximate algorithm(VOGEL+ stochastic simulation)is proposed by using VOGEL method of solving of transportation problem and method of random simulation.And the classical genetic algorithm are presented.Finally,By using two kinds of algorithm and has carried on the contrast,a numerical example is given to illustrate effectiveness of the model and the algorithm.