Aiming at the problems of low efficiency, low accuracy and poor safety of the current automatic route selection method for shipping transportation, an automatic route selection method for shipping transportation based...
详细信息
Aiming at the problems of low efficiency, low accuracy and poor safety of the current automatic route selection method for shipping transportation, an automatic route selection method for shipping transportation based on heuristic algorithm is proposed. The index system for route selection in shipping transportation is constructed. The model of route selection in shipping transportation is established by using set variables, parameter variables, decision variables, objective functions and constraints and the model is solved by using inertia factors and learning factors. The route selection in shipping transportation is designed, and the maximum probability of route selection in shipping transportation is calculated and the constructed route is updated locally. It enlarges the difference of pheromones between the optimal and the worst routes, makes the search behavior to select the transportation route of goods more quickly, and finally realizes the automatic selection of the shipping transportation route. The experimental results show that the method has high efficiency, accuracy and safety in the automatic route selection of shipping transportation.
In this work, we tackle problem of integrated delivery-inventory for the supply of multi items to more than one customer, after its production by a manufacturer to minimize the total delivery and storage costs. A math...
详细信息
In this work, we tackle problem of integrated delivery-inventory for the supply of multi items to more than one customer, after its production by a manufacturer to minimize the total delivery and storage costs. A mathematical model incorporating the costs of both the delivery and the storage costs is developed as a Mixed Integer Programming model (MIP). The proposed approach is an heuristic algorithm where in the first phase, a heuristic search is deployed to construct a sequence of batches and in the second the batches are scheduled accord to the due dates of the jobs. Extensive experiments are conducted to evaluate the efficiency of the algorithm in terms of time of resolution and solution quality. The evaluation is carried out against the solutions generated by the exact mathematical model of the problem. Experimental results demonstrate that, the proposed heuristic algorithm is robust in term of time of resolution and generates feasible solutions for the instances where the MIP model cannot. (C) 2015, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.
In this paper an effective search-type heuristic algorithm for the problems of scheduling activities under resource and precedence constraints is presented. Such problems are typically massive in size and combinatoria...
详细信息
This paper analyzes a dynamic lot-sizing problem, in which the order size of multiple products and a single container type are simultaneously considered. In the problem, each order (product) placed in a period is imme...
详细信息
This paper analyzes a dynamic lot-sizing problem, in which the order size of multiple products and a single container type are simultaneously considered. In the problem, each order (product) placed in a period is immediately shipped by some containers in the period and the total freight cost is proportional to the number of containers used. It is also assumed that backlogging is not allowed. The objective of this study is to simultaneously determine the lot-sizes and the transportation policy that minimizes the total costs, which consist of production cost, inventory holding cost, and freight cost. Because this problem is NP-hard, a heuristic algorithm with an adjustment mechanism is proposed based on the optimal solution properties. The computational results from a set of simulation experiment are also presented. (c) 2005 Elsevier B.V. All rights reserved.
This paper describes a new design of Tabu Search (TS) algorithm for solving the Vehicle Routing Problem with Time Windows (VRPTW). Since VRPTW is a well known NP-hard problem, heuristic algorithms such as Tabu Search ...
详细信息
ISBN:
(纸本)9781424423873
This paper describes a new design of Tabu Search (TS) algorithm for solving the Vehicle Routing Problem with Time Windows (VRPTW). Since VRPTW is a well known NP-hard problem, heuristic algorithms such as Tabu Search are always used to get a good approach. The former published designs of TS usually focus on the neighbor structure, the relaxation to the objective function or the multi-period algorithms. This paper has two contributions. First, it designs an objective value-based Tabu List structure to help decreasing the tabu list size and escape from local optima. it still adopts some tactics like adaptive tabu size, randomly selected neighbor structure and so on. Second, from a problem oriented point of view, it shows that, with this self-adaptive Tabu List, even five kinds of simple neighbor structures and a single period algorithm with original objective function can get very good solutions. We tested this algorithm with Solomon's VRPTW benchmark problems, and 7 of the best known solutions are updated. Another advantage of this algorithm is its efficiency. It runs on an average of 80 seconds on a normal personal computer for a solution of a problem with 100 customers.
In this paper, the network expanded problem (NEP) which optimally assigns new adding and splitting cells in PCS (Personal Communication Service) network to switches in an ATM (Asynchronous Transfer Mode) network is st...
详细信息
ISBN:
(纸本)9783540744689
In this paper, the network expanded problem (NEP) which optimally assigns new adding and splitting cells in PCS (Personal Communication Service) network to switches in an ATM (Asynchronous Transfer Mode) network is studied. In NEP, the locations of all cells (or Base Station, BS) in PCS network are fixed and known, but new switches should be installed to ATM network and the topology of the backbone network may be changed. Given some potential sites of new switches, the problem is to determine how many switches should be added to the backbone network, the locations of new switches, the topology of the new backbone network, and the assignments of new adding and splitting cells in the PCS to switches on the new ATM backbone network in an optimum manner. The goal is to do the expansion in as attempt to minimize the total communication cost under budget and capacity constraints. The NEP is modeled as a complex integer programming problem and finding an optimal solution to this problem is NP-hard. A heuristic algorithm is proposed to solve this problem. The proposed heuristic algorithm consists of four phases: Remaining Capacities Pre-assigning Phase (RCPP), Cell Clustering Phase (CCP), Switch Selection Phase (SSP), and Backbone Design Phase (BDP). Experimental results indicate that the proposed algorithm can find good solution.
Transportation investment is a difficult decision, especially in developing countries where numerous improvements are needed but only limited resources are available. Although many studies have suggested that the netw...
详细信息
In this paper, The traditional vehicle routing problem with time windows is expanded to the situation that the time window is replaced by fuzzy due time which can represent the preferences of the customers. After a si...
详细信息
ISBN:
(纸本)9781479951482
In this paper, The traditional vehicle routing problem with time windows is expanded to the situation that the time window is replaced by fuzzy due time which can represent the preferences of the customers. After a simple description of fuzzy due time and the fuzzy vehicle routing problem, a multi-objective mathematical model for the problem is built. Then, an insertion heuristic-based hybrid genetic algorithm is proposed to this kind of problem. In this algorithm, the modified push-bump-throw procedure is employed to handle the fuzzy nature of the problem. Finally, an extensive computational analysis is presented, which identifies the tradeoffs between the different objectives, and the superiority of the genetic algorithm is proved through the comparison of the genetic algorithms with improved Solomon insert heuristic algorithm.
Weather is one of the most important factors threatening the safety of general aviation. It is necessary to avoid the possible hazardous weather regions according to the weather forecast in the planning stage. In this...
详细信息
ISBN:
(纸本)9781728104898
Weather is one of the most important factors threatening the safety of general aviation. It is necessary to avoid the possible hazardous weather regions according to the weather forecast in the planning stage. In this paper. a flight path planning method based on phased altitude changes is proposed. The influence of hazardous weather in different altitudes of the airspace is discretized into gridding polygons. In order to evaluate the influence of hazardous weather on flight paths, flight distance is used to construct cost function and maneuver of the aircraft is modeled as the constraint condition. As the result, a flight path with minimum cost is planned using heuristic algorithm in the gridding system. Numerical simulations show that the flight distance of the path planned by the proposed method is shorter than the planned path that with a constant flight altitude.
A heuristic polynomial algorithm is presented, which is used for the recognition of isomorphism of graphs and can be assigned to the group of methods that use local characteristic invariants of graphs. At each step, t...
详细信息
暂无评论