Solving resource availability cost problem in project scheduling by pseudo particle swarm optimization

This paper considers a project scheduling problem with the objective of minimizing resource availability costs appealed to finish al activities before the deadline. There are finish-start type precedence relations among the activities which require some kinds of renewable resources. We predigest the process of sol-ving the resource availability cost problem （RACP） by using start time of each activity to code the schedule. Then, a novel heuris-tic algorithm is proposed to make the process of looking for the best solution efficiently. And then pseudo particle swarm optimiza-tion （PPSO） combined with PSO and path relinking procedure is presented to solve the RACP. Final y, comparative computational experiments are designed and the computational results show that the proposed method is very effective to solve RACP.

Bottleneck Analysis of the Minimum Cost Problem for the Generalized Network Based on Augmented Forest Structure

The bottleneck analysis of the minimum coat problem for the generalized netwok(MCPGN) is discussed.The analysis is based on the network simplex algorithm,which gains negative cost graphs by constructing augmented forest structure,then augments flows on the negative cost graphs until the optimal revolution is gained Bottleneck structure is presented after analyzing the augmented forest structure.The negative cost augmented graphs are constructed with the bottleneck structure.The arcs that block the negative cost augmented graph are the elements of the bottleneck.The bottleneck analysis for the generalized circulation problem,the minimum circulation problem and the circulation problem are discussed respectively as the basal problems,then that for MCPGN is achieved.An example is presented at the end.

A TRUST REGION ALGORITHM VIA BILEVEL LINEAR PROGRAMMING FOR SOLVING THE GENERAL MULTICOMMODITY MINIMAL COST FLOW PROBLEMS

This paper proposes a nonmonotonic backtracking trust region algorithm via bilevel linear programming for solving the general multicommodity minimal cost flow problems.Using the duality theory of the linear programming and convex theory,the generalized directional derivative of the general multicommodity minimal cost flow problems is derived.The global convergence and superlinear convergence rate of the proposed algorithm are established under some mild conditions.

Some Remarks on Application of Sandwich Methods in the Minimum Cost Flow Problem

In this paper, two new sandwich algorithms for the convex curve approximation are introduced. The proofs of the linear convergence property of the first method and the quadratic convergence property of the second method are given. The methods are applied to approximate the efficient frontier of the stochastic minimum cost flow problem with the moment bicriterion. Two numerical examples including the comparison of the proposed algorithms with two other literature derivative free methods are given.

Optimal investment with transaction costs based on exponential utility function:a parabolic double obstacle problem

This paper concerns optimal investment problem with proportional transaction costs and finite time horizon based on exponential utility function. Using a partial differential equation approach, we reveal that the problem is equivalent to a parabolic double obstacle problem involving two free boundaries that correspond to the optimal buying and selling policies. Numerical examples are obtained by the binomial method.

Competitive analysis of price online inventory problem with cost function

In this paper,a new price is given to the online decision maker at the beginning of each day.The trader must decide how many items to purchase according to the current price.We present three variants and an online algorithm based on cost function.The competitive ratio of the online algorithm is given for each variant,which is a performance measure of an online algorithm.More importantly,we show that the online algorithm is optimal.

Study on the Transportation Problem of Petrol Secondary Distribution with Considering Shortage Cost

Petrol is a kind of strategic natural resources. Provide legitimate transportation plans for the petrol secondary distribution are the key links to guarantee the petrol provision. If the total supply is insufficient, some petrol stations can’t avoid shortage because their demands could not be met. So the shortage cost will appear. This paper studies the problem of how to arrange the transportation plan in order to minimize the total cost when the total volume of supply is insufficient. Given the storage volume, the sales rate and the unit shortage cost of every petrol station, considering the full loading constraints of the compartment vehicle, a mixed integer programming model for minimizing the total cost of petrol secondary distribution is established. A Lingo program is compiled for solving the model. Finally, simulation on an example has been done and a reasonable transportation plan is obtained. The model and algorithm in this paper can provide a theoretical basis for dispatching department to make transportation plan.

Reducing a Lot Sizing Problem with Set up, Production, Shortage and Inventory Costs to Lot Sizing Problem with Set up, Production and Inventory Costs

We reduce lot sizing problem with (a) Set Up, Production, Shortage and Inventory Costs to lot sizing problem with (b) Set Up, Production, and Inventory Costs. For lot sizing problem (as in (b)), Pochet and Wolsey [1] have given already integral polyhedral with polynomial separation where a linear program yield “integer” solutions. Thus problem (b) which we have created can be more easily solved by methods available in literature. Also with the removal of shortage variables is an additional computational advantage.

Minimum Cost of Capacity Expansion for Time-Limited Transportation Problem On-Demand

The minimum cost of capacity expansion for time-limited transportation problem on-demand (MCCETLTPD) is to find such a practicable capacity expansion transportation scheme satisfying the time-limited T along with all origins’ supply and all destinations’ demands as well as the expanding cost is minimum. Actually, MCCETLTPD is a balance transportation problem and a variant problem of minimum cost maximum flow problem. In this paper, by creating a mathematical model and constructing a network with lower and upper arc capacities, MCCETLTPD is transformed into searching feasible flow in the constructed network, and consequently, an algorithm MCCETLTPD-A is developed as MCCETLTPD’s solution method basing minimum cost maximum flow algorithm. Computational study validates that the MCCETLTPD-A algorithm is an efficient approach to solving the MCCETLTPD.

混合遗传变邻域搜索算法求解柔性车间调度问题

针对考虑生产成本的柔性作业车间调度问题(flow job shop scheduling problem, FJSP),以完工时间与加工成本为优化指标,提出一种求解FJSP的混合遗传变邻域搜索算法。根据个体适应度对种群分割,结合自适应交叉概率改进子代种群产生方式;设计两种邻域结构增强算法的局部搜索能力;提出一种基于动态交叉变异概率的优化算法流程提高求解效率。运用提出的算法求解基准实例与实际问题测试,验证了算法的有效性。

考虑鲁棒成本与绝对后悔的最短路径问题研究

为克服鲁棒偏差方法在处理区间路网时所求鲁棒最短路径的保守性问题,通过分析鲁棒成本的定义以及鲁棒最短路径过于保守的原因,结合算例分析提出了绝对后悔值的概念,并以鲁棒成本和绝对后悔值为目标函数建立了区间路网的多目标最短路径模型;根据最短路径模型的特点设计了分离路径决策变量与连续变量的Benders分解算法,同时基于传统有效路径的判断依据重新定义了符合该最短路径模型的有效路径,并在分解后的主问题模型中引入了有效路径约束以加快算法收敛速度;利用MATLAB生成了一个包含29个节点、70条双向通行路段的区间路网对模型与算法进行仿真测试。结果表明:考虑鲁棒成本和绝对后悔值的最短路径模型能在区间路网中找到不保守,且同时兼具鲁棒性的最短路径,能够有效克服鲁棒偏差方法的缺陷。

An Algorithm Based on Mobile Agent for Delay Constrained Least Cost Unicast Routing

The delay constrained least cost path problem with imprecise delay information is discussed, and a distributed heuristic algorithm without any assumption of imprecise state information is presented. The algorithm employs mobile agents to search feasible paths in parallel and requires limited network state information kept at each node. The simulations indicate that the presented solution provides better call acceptance probability and better fairness between short paths and long paths. And the algorithm can tolerate high degree of delay imprecision.

动态环境下基于换电模式的电动车路径问题研究

在实际配送中,考虑车速受不同天气、不同时段的影响,根据电动车辆行驶速度与能耗之间的函数关系,以电动车固定行驶成本、能耗成本、时间惩罚成本构成的总运输费用最小为目标,以车辆载重、车辆电池容量、客户时间窗、车辆速度为约束条件,构建动态环境下基于换电模式和时变速度的电动汽车路径优化模型。用遗传算法对模型求解,采用实数编码、轮盘赌选择算子、随机单点交叉、随机变异的方式,并以小变异率提高局部搜索能力,然后与车辆速度恒定时的几种情况进行对比。试验结果表明,所建立的优化模型更符合实际情况,能够根据客户属性和动态环境下的路网特性,合理安排发车、规划配送路径和顺序,从而降低配送成本,为物流企业运营车辆和优化配送提供参考。

公园建设项目成本管理与优化策略研究

为解决公园建设项目成本管理存在的问题,对公园建设项目成本管理的现状进行了分析,针对性地提出了优化策略。公园建设项目成本管理需制订科学合理的成本管理计划、加强成本核算和监控、推进信息化手段应用、强化供应链管理以及实施成本控制措施等优化策略。通过在案例工程中进行应用,验证了这些策略的可行性和实际效果,提高了公园建设项目的成本管理水平,实现了企业的可持续发展,总结的经验可供其他公园类建设项目进行成本管理时参考。

建筑工程造价管理的现状及对策研讨

剖析当前建筑工程造价管理中存在的问题,涉及造价控制、施工成本动态管控、建筑工程限额设计、招标控制与审计管理以及工程造价管理人员素质等方面。提出了优化设计方案造价管理、落实施工成本动态管控、实行建筑工程限额设计、强化招标控制与审计管理和提高工程造价管理人员素质等对策。

建筑工程造价中存在的问题与对策的分析

我国经济的飞速发展,使工程建设也进入快速发展阶段,无论是建筑工程的规模还是数量都在不断地增加。因为建筑工程是一项很大的工程,所以资金投入巨大,造价管理就成为建筑工程管理中的重心。做好工程造价管理工作不但可以降低工程的成本,还能提升工程项目的经济效益,同时减少不必要的浪费。但并不能要一味地提高造价管理水平,而是应该在保证工程建设的基础之上,最大限度地控制成本,减少资金的浪费,最大化地提升经济效益和社会效益。文中对当前我国工程造价管理中的问题展开探析,同时根据这些问题提出相应的解决对策,以给造价管理工作提供参考。

建筑工程造价与成本控制管理的研究

在改革开放深化背景下,我国经济呈现稳步发展趋势,为建筑行业的快速发展营造了良好环境,建筑企业快速发展的同时面临着诸多风险因素,在一定程度限制了上企业的可持续发展。要想有效管理施工项目成本,建筑企业就要控制好建筑工程造价。建筑企业需要通过积累资本才能得到更好的发展,提高经济效益,因此本文就如何把控工程造价各环节的成本,优化现阶段工程造价与成本控制管理存在的问题进行分析研究。

企业成本管理存在的问题及解决策略

随着我国社会主义市场经济体制改革持续深入推进,涌现出了越来越多的中小型企业并得到快速发展,加大了市场竞争压力,在此环境下,企业所面临的外部市场环境更加复杂多变,因此对企业成本管理与控制提出了更高的要求。企业要对自身发展过程中的不足进行深入分析,要深刻意识到高质量的成本管控对企业自身长远发展的重要性,在此基础上不断优化完善成本管理和控制体系,以此来提升成本管理质量,推动企业长远发展。

机械制造企业成本控制问题及对策分析

结合机械制造企业成本控制的现状,深入分析企业成本控制的主要问题,从人员培训、物流管理、供应链管理、质量成本等方面针对性提出了制造企业成本控制的对策措施,从而推动企业构建全面成本控制机制,实现高质量、可持续健康发展.

基于建筑工程成本管理及常见问题分析

建筑工程的成本控制管理是建筑工程项目组织实施中需要重点强调的内容之一,其直接影响着企业效益,对现阶段建筑企业的成本管理工作进行分析可知其存在的问题是较多的,且问题表现在多个方面,如意识、方面、技术方面。面对成本管理存在的显著问题,针对问题提出解决策略,这对于成本管理的实际效果提升是有显著价值的。本文就相关内容展开分析与讨论,旨在为目前的工程实践提供参考与指导。