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1.
短生命周期产品因为需求的随机性和产品价值的瞬间变化性,对预测准确性提出了更高的要求.然而许多企业在使用多种预测模型后发现其预测准确率并没有得到显著提升.以短生命周期产品需求特点为背景,在需求预测影响的BASS模型基础上,建立受生命周期和季节性因素影响的需求预测优化模型,最后通过一个产品的实例证实了验证了模型的合理性.  相似文献   

2.
张玲  赖芸 《运筹与管理》2019,28(11):98-105
台风自然灾害具有强大的破坏力经常会引起一系列的连锁事件导致多米诺效应。本文考虑在对初始事故多米诺效应分析的基础上预测应急资源的需求,并建立应急资源配置的鲁棒优化模型。首先,本文对初始事故多米诺效应发展机理进行分析,并结合经验估计方法确定若干不同情景,进行应急资源需求预测;然后,建立了两阶段应急资源配置规划模型,并利用鲁棒优化的思想和情景松弛算法对模型进行求解,从而得到合理的资源配置方案。数值实验表明,建立的模型是有效并且可行的。  相似文献   

3.
针对舰船装备临修经费需求预测得不到满意解的问题,运用遗传算法将SVM相应的参数进行优化,建立了基于GA-SVM的舰船装备临修经费预测模型.通过将GA-SVM模型与BP神经网络模型的预测结果进行对比分析,结果表明:GASVM的预测效果更优异,对舰船装备临修经费需求预测有更好的参考意义.  相似文献   

4.
通过对当前电视广告的商业运行模式进行分析,建立了分户推送广告模型和组织竞价交易模型.首先,在分户推送广告模型中,建立了用户向量和广告向量,基于PageRank算法和模糊匹配的静态匹配模型确定了广告与用户的匹配度,并根据用户的历史收视情况和广告商品的销量增长情况更新用户向量和广告向量;其次,在组织竞价交易模型中,根据同类别其他电视台该时段的广告成交价格区间和相关因素来确定各时段广告的合理底价,通过信誉度和可信有效竞价来确定某时段广告的单位成交价格,在极大化卖方收益的同时提高了收视率和买方产品的销售量;最后,通过算例对模型进行了验证,并与现有的推送及竞价交易模式进行了比较.  相似文献   

5.
股票市场中当交易规模较大时,投资者不仅要预判未来的股票价格趋势从而降低风险成本,也要考虑大额交易指令对市场冲击的成本.在投资者预判股票未来价格趋势的同时,考虑交易量的线性价格冲击,建立一个控制最小交易成本的策略模型,采用随机动态规划方法得出总体执行成本最小的交易策略解析解,进一步利用数值算例对最优交易策略进行了比较静态分析.  相似文献   

6.
物流需求预测是物流园区整体规划的重要前提,准确的物流需求预测可以大大提高物流园区规划的科学性.首先建立了趋势曲线预测模型、回归预测模型及灰色预测模型的物流需求单项预测模型,鉴于单项预测模型的局限性,然后以Shapley值为权重确定方法,建立了组合预测模型,并以重庆空港物流园为例进行应用,最后得出了2015年和2020年重庆空港物流园物流需求的预测值.研究表明,组合预测比单项预测具有更高的精度和稳定性,方法在物流园区物流需求预测中具有推广应用价值.  相似文献   

7.
中国将同时实施可再生能源配额制与碳排放权交易,并以售电商为配额制的考核主体。本文建立两级供应链模型分析两者相互作用的政策效果。研究结果表明,引入碳排放权交易将导致火电价格上涨与可再生能源电力价格下降,有利于实现两者在同一价格水平竞争。然而,碳排放权交易亦将造成零售电价上涨,电力需求减少,且变化幅度与碳排放权价格和减排成本成正比。若配额比例与售电商差异性提高,在不影响环境成本内化于火电批发价格的同时,可降低售电商的转嫁成本。从而减小了可再生能源电力价格降幅与零售电价涨幅,并平抑碳排放权价格与减排成本上涨造成的电价与需求波动。  相似文献   

8.
薛桂琴  王征 《运筹与管理》2021,30(11):19-25
随着互联网商业迭代的不断深化,越来越多的企业倾向于从商品前置视角解决配送距离与配送时效性的矛盾。为此,本文研究基于客户协同分仓备货的动态车辆调度问题(Dynamic Vehicle Routing Problem with Inventory Synergetic Customer, DVRP-ISC),设计考虑区域分异特征的协同分仓客户选择方法,建立多阶段动态配送网络优化模型。鉴于研究问题的特殊性,设计多阶段两级网络协同配送路径优化算法;最后,以仿真算例、自定义算例集和基准算例,验证所提模型和算法性能及其拓展性。  相似文献   

9.
如何实现供应链需求预测的有效协同是一个需要解决的难点问题。论文基于博弈论分析了协同需求预测的利益分配机制,定量分析了供应链协同需求预测的整体收益系数,提出了考虑收益和成本的动态激励机制,还定性分析了核心企业主导、信息共享以及信任等机制。提出的机制对提高供应链整体的预测能力,提升竞争力和整体绩效具有很好的价值。  相似文献   

10.
基于现实配送过程中配送时间存在着不确定性,通过配送时间模糊化处理构建出跨区域鲜果电商配送模糊网络流模型,进而根据实际配送时间与期望配送时间的偏离建立顾客满意度函数,然后构建由满意度降低引起的惩罚成本函数,并根据鲜果成熟度变化特性建立带有模糊时间和成熟度的跨区域鲜果电商配送最小成本路线优化模型。在求解过程中利用三种去模糊化方法(重心法、积分法和α-cut法)对模糊时间进行处理,并结合现有的整数规划算法对模型进行求解,得出最佳配送路线并进行对比分析。结果表明:(1)根据鲜果成熟度水平选择适当的配送路线可以有效降低配送成本,保证鲜果品质;(2)在去模糊化方面α-cut法比重心法和积分法所得结果更具有一般性。  相似文献   

11.
基于网络分析方法的物流配送中心选址的研究   总被引:11,自引:1,他引:10  
经济全球化。信息技术和电子商务的发展对物流产生了深刻的影响。使之呈现出新的特点。这些特点对配送中心选址的研究提出了更高,更新的要求。本在对GIS网络分析方法的阐述和P中心选址模型的分析的基础上,建立了配送中心选址优化模型。该模型通过引入商品保管费用、处理费用、配送中心建造费用对P中心选址模型进行了拓展,并通过总费用最小化确定配送中心的数量、位置以及资源点与配送中心、配送中心与用户之间的供需关系。  相似文献   

12.
针对金属矿山企业的单位开采与运输成本大、优化求解结果偏差大问题, 首先, 依据金属矿山企业编制开采计划的基本原则, 以矿石开采与运输成本最小化为优化目标, 利用整数规划方法, 构建了金属矿山企业生产计划数学模型, 其次, 为了精准快速求解金属矿山企业生产计划模型, 提出了改进的量子粒子群优化算法, 采用进化速度和聚集度因子对算法中的惯性权重进行动态调整, 并设计了双层可行域搜索策略, 提高了算法的局部和全局搜索能力。最后, 以某大型金属矿山企业采运生产作业为案例, 通过与矿山实际生产指标、非线性规划结果以及粒子群优化结果进行比较分析。结果表明:在相同经济指标和参数环境下, 本文算法优于其它两种优化方法, 且每吨矿石的开采和运输成本减少了0.05元左右, 降低了金属矿山企业的开采运输成本, 提高了企业的整体经济效益。  相似文献   

13.
In this paper, we develop a supply chain network model in which both physical and electronic transactions are allowed and in which supply side risk as well as demand side risk are included in the formulation. The model consists of three tiers of decision-makers: the manufacturers, the distributors, and the retailers, with the demands associated with the retail outlets being random. We model the optimizing behavior of the various decision-makers, with the manufacturers and the distributors being multicriteria decision-makers and concerned with both profit maximization and risk minimization. We derive the equilibrium conditions and establish the finite-dimensional variational inequality formulation. We provide qualitative properties of the equilibrium pattern in terms of existence and uniqueness results and also establish conditions under which the proposed computational procedure is guaranteed to converge. We illustrate the supply chain network model through several numerical examples for which the equilibrium prices and product shipments are computed. This is the first multitiered supply chain network equilibrium model with electronic commerce and with supply side and demand side risk for which modeling, qualitative analysis, and computational results have been obtained.  相似文献   

14.
This paper presents a dynamic logistics model for medical resources allocation that can be used to control an epidemic diffusion. It couples a forecasting mechanism, constructed for the demand of a medicine in the course of such epidemic diffusion, and a logistics planning system to satisfy the forecasted demand and minimize the total cost. The forecasting mechanism is a time discretized version of the Susceptible-Exposed-Infected-Recovered model that is widely employed in predicting the trajectory of an epidemic diffusion. The logistics planning system is formulated as a mixed 0–1 integer programming problem characterizing the decision making at various levels of hospitals, distribution centers, pharmaceutical plants, and the transportation in between them. The model is built as a closed-loop cycle, comprising forecast phase, planning phase, execution phase, and adjustment phase. The parameters of the forecast mechanism are adjusted in reflection of the real data collected in the execution phase by solving a quadratic programming problem. A numerical example is presented to verify efficiency of the model.  相似文献   

15.
图论、最优化理论显然在蛋白质结构的研究中大有用场. 首先, 调查/回顾了研究蛋白质结构的所有图论模型. 其后, 建立了一个图论模型: 让蛋白质的侧链来作为图的顶点, 应用图论的诸如团、 $k$-团、 社群、 枢纽、聚类等概念来建立图的边. 然后, 应用数学最优化的现代摩登数据挖掘算法/方法来分析水牛普里昂蛋白结构的大数据. 成功与令人耳目一新的数值结果将展示给朋友们.  相似文献   

16.
基于混合算法的实时订货信息下的车辆调度优化   总被引:2,自引:0,他引:2  
实时订货信息下的车辆调度是随机性车辆调度中货物需求量、需求点均不确定的情况下的车辆调度.针对该问题,本文构建了配送总成本最小的目标函数,提出了采用混合算法求解的思路.即以局部搜索法求得初始解,采用遗传算法优化初始解,并在送货时间更新后,利用禁忌搜索法求解速度快的特点改进调度方案,得到订货信息不断更新的条件下的车辆调度方案.通过实例分析,本方法既可解决电子商务条件下实时订货的车辆调度问题,也具有求解结果可靠、求解过程快速的特点.  相似文献   

17.
The aim of minimal cost flow problem (MCFP) in fuzzy nature, which is denoted with FMCFP, is to find the least cost of the shipment of a commodity through a capacitated network in order to satisfy imprecise concepts in supply or demand of network nodes and capacity or cost of network links. Fuzzy supply–demand may arise in real problems, where incomplete statistical data or simulation results are used. Also, variation in the cost or capacity of links is commonly happening. In the present paper, after defining a total order on LR type fuzzy numbers, three models are studied; MCFP with fuzzy costs, MCFP with fuzzy supply–demand and a combination of two cases. For the first model, scaling negative cycle cancelling algorithm, which is a polynomial time algorithm, is proposed. For the second model, “nominal flow” is introduced which provides an efficient scheme for finding fuzzy flow. For the third model, we present an exact and some heuristic methods. Numerical examples are illustrated to demonstrate the efficiency of the proposed schemes. Finally, an application of this viewpoint in bus network planning problem is provided.  相似文献   

18.
Planning horizon is a key issue in production planning. Different from previous approaches based on Markov Decision Processes, we study the planning horizon of capacity planning problems within the framework of stochastic programming. We first consider an infinite horizon stochastic capacity planning model involving a single resource, linear cost structure, and discrete distributions for general stochastic cost and demand data (non-Markovian and non-stationary). We give sufficient conditions for the existence of an optimal solution. Furthermore, we study the monotonicity property of the finite horizon approximation of the original problem. We show that, the optimal objective value and solution of the finite horizon approximation problem will converge to the optimal objective value and solution of the infinite horizon problem, when the time horizon goes to infinity. These convergence results, together with the integrality of decision variables, imply the existence of a planning horizon. We also develop a useful formula to calculate an upper bound on the planning horizon. Then by decomposition, we show the existence of a planning horizon for a class of very general stochastic capacity planning problems, which have complicated decision structure.  相似文献   

19.
Biopharmaceutical manufacturing requires high investments and long-term production planning. For large biopharmaceutical companies, planning typically involves multiple products and several production facilities. Production is usually done in batches with a substantial set-up cost and time for switching between products. The goal is to satisfy demand while minimising manufacturing, set-up and inventory costs. The resulting production planning problem is thus a variant of the capacitated lot-sizing and scheduling problem, and a complex combinatorial optimisation problem. Inspired by genetic algorithm approaches to job shop scheduling, this paper proposes a tailored construction heuristic that schedules demands of multiple products sequentially across several facilities to build a multi-year production plan (solution). The sequence in which the construction heuristic schedules the different demands is optimised by a genetic algorithm. We demonstrate the effectiveness of the approach on a biopharmaceutical lot sizing problem and compare it with a mathematical programming model from the literature. We show that the genetic algorithm can outperform the mathematical programming model for certain scenarios because the discretisation of time in mathematical programming artificially restricts the solution space.  相似文献   

20.
Visual analytics is the science of analytical reasoning facilitated by interactive visual interfaces. In this paper, we present an adaptation of the visual analytics framework to the context of software understanding for maintenance. We discuss the similarities and differences of the general visual analytics context with the software maintenance context, and present in detail an instance of a visual software analytics application for the build optimization of large-scale code bases. Our application combines and adapts several data mining and information visualization techniques in answering several questions that help developers in assessing and reducing the build cost of such code bases by means of user-driven, interactive analysis techniques.  相似文献   

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