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1.
The focus of this research is on supplying gasoline after a natural disaster. There are two aspects for this work: determination of which gas stations should be provided with generators (among those that do not have electric power) and determination of a delivery scheme that accounts for increased demand due to lack of public transportation and considerations such as equity. We develop a mixed integer program for this situation. Two case studies based on Hurricane Sandy in New Jersey are developed and solved in CPLEX. As expected, increasing equity increases cost and also tends to place generators to stations with large initial inventories. It is further observed that CPLEX can solve the largest instances of the problem for a 5% tolerance gap, indicating that the model is efficient.  相似文献   

2.
    
Models for the distribution of relief supplies often assume immediate availability of relief items upon the occurrence of a natural disaster. However, such an assumption does not always apply in realistic settings. In some cases, at least it is necessary to assemble relief items into kits before distributing them among the affected population. This paper presents a rolling horizon methodology that considers dynamic parameters such as demand, capacities and demand priorities for the problem of distributing relief supplies after the occurrence of a natural disaster by including such assembling activities before the delivery.  相似文献   

3.
The paper argues that welfare economic principles must be incorporated in post-disaster humanitarian logistic models to ensure delivery strategies that lead to the greatest good for the greatest number of people. The paper's analyses suggest the use of social costs—the summation of logistic and deprivation costs—as the preferred objective function for post-disaster humanitarian logistic models. The paper defines deprivation cost as the economic valuation of the human suffering associated with a lack of access to a good or service. The use of deprivation costs is evaluated with a review of the philosophy and the economic literature to identify proper foundations for their estimation; a comparison of different proxy approaches to consider human suffering (e.g., minimization of penalties or weight factors, penalties for late deliveries, equity constraints, unmet demands) and their implications; and an analysis of the impacts of errors in estimation. In its final sections, the paper conducts numerical experiments to illustrate the comparative impacts of using the proxy approaches suggested in the literature, and concludes with a discussion of key findings.  相似文献   

4.
This paper proposes a logistics model for delivery of prioritized items in disaster relief operations. It considers multi-items, multi-vehicles, multi-periods, soft time windows, and a split delivery strategy scenario, and is formulated as a multi-objective integer programming model. To effectively solve this model we limit the number of available tours. Two heuristic approaches are introduced for this purpose. The first approach is based on a genetic algorithm, while the second approach is developed by decomposing the original problem. We compare these two approaches via a computational study. The multi-objective problem is converted to a single-objective problem by the weighted sum method. A case study is presented to illustrate the potential applicability of our model. Also, presented is a comparison of our model with that proposed in a recent paper by Balcik et al. [6]. The results show that our proposed model outperforms theirs in terms of delivering prioritized items over several time periods.  相似文献   

5.
    
During the preparation before a hurricane makes landfall, affected individuals may be asked to evacuate. Large and small-scale evacuations can cause rapid increases in the demand for gasoline fuel. However, during a hurricane vessels carrying gas may be delayed and/or rerouted, adding to the difficulty of providing the necessary gas in affected areas. In this work, we determine alternate delivery locations and times for vessels carrying fuel that are scheduled to arrive and deliver fuel at ports impacted by an approaching hurricane. Motivated by Hurricane Irma in Florida, we develop a multi-period stochastic scheduling model that incorporates hurricane (weather) advisories, fuel delivery schedules, port storage capacities, and port docking capacities. Our model determines the best schedule based on two objectives: (1) minimize the total unmet demand at each port, and (2) minimize inequities in unmet demands among the ports. We also present a case study and a numerical experiment based on fuel delivery data from ports in Florida. Among our key findings is that port availability is the driving factor in determining feasible schedules for vessel gas deliveries. We also present a scheduling heuristic that dynamically adapts to weather advisories so as to minimize the impact of unmet demand in the affected areas.  相似文献   

6.
    
Humanitarian assistance is meant to save lives and alleviate human suffering during and in the aftermath of man-made and natural disasters. To prevent and strengthen preparedness for the occurrence of such situations, having available relief supplies in the short-term becomes crucial. The lack of access to life-sustaining items implies a loss in people's welfare, treated as an externality called deprivation costs which must be incorporated into decision-making processes. Since typical humanitarian applications are extensions of commercial logistic models, they usually do not account for externalities, leading to high social costs and likely to unfeasible or suboptimal solutions.This paper develops a facility location model for prepositioning supplies in preparation for disasters; the key feature of this formulation being the fact that it explicitly considers deprivation costs in the objective function. The model attempts to minimize the global social costs, as the sum of both private costs (i.e. costs of transportation, inventory costs and fixed costs of facilities) and deprivation costs, determining the amount per type of product to be prepositioned for serving the areas affected by a disaster during the initial response. The model focuses on those assistance interventions that should be carried out immediately, i.e. within the first 24 h of a humanitarian crisis. We applied the model, using real information, to the Colombian Caribbean region, which was affected by floods in 2010 and 2011. Results demonstrate that deprivation costs represent more than 50% of the total social cost.  相似文献   

7.
    
In case of disaster, providing relief supplies to the affected people has vital importance. Governmental or non-governmental organizations (NGOs) prepare for disasters by purchasing and stockpiling these aid materials in appropriate quantities. They operate under a limited budget and this budget can either be used before the disaster for stocking decisions under uncertainty or it can be used after the disaster to satisfy the required demand at a higher cost when the uncertainty is resolved. If all the budget is used before the disaster, and if there is no disaster in a long term, there will be a high holding cost. On the other hand, if all the budget is reserved for use after the disaster, meeting the demand will be more costly or the demand may not be met within a certain period of time. Thus, NGOs need to decide how to allocate the budget for pre and post-disaster usage. In this system, the budget of NGOs may also change over time through donations or other incomes. In this point of view, NGOs need to make dynamic stock and budget allocation decisions, under the available budget at hand. In our study, we analyze the dynamic stocking decisions of NGOs using stochastic dynamic programming formulations under budget constraints. We develop infinite horizon stochastic dynamic programming models with and without budget considerations, and compare the results of these models via numerical analysis. Detailed numerical studies and results of the sensitivity analysis show the significance of budget considerations in inventory decisions and the effects of different parameters on the system results.  相似文献   

8.
市场供给和市场需求的均衡发展.是第三方物流市场健康发展的必要条件。物流市场需求包括需求数量和需求质量两个方面,中国物流市场虽已启动.却因物流有效需求不足,特别是物流需求质量的低下.而未被激活。物流需求质量的提升,将为第三方物流的发展提供动力。  相似文献   

9.
Debris occurs from the ruin and wreckage of structures during a disaster. Proper removal of debris is of great importance because it blocks roads and prohibits emergency aid teams from accessing disaster-affected regions. Poor disaster management, lack of efficiency and delays in debris removal cause disruptions in providing shelter, nutrition, healthcare and communication services to disaster victims, and more importantly, result in loss of lives. Due to the importance of systematic and efficient debris removal from the perspectives of improving disaster victims quality of life and allowing the transportation of emergency relief materials, the focus of this study is on providing emergency relief supplies to disaster-affected regions as soon as possible by unblocking roads through removing the accumulated debris. We develop a mathematical model for the problem that requires long CPU times for large instances. Since it is crucial to act quickly in an emergency case, we also propose a heuristic methodology that solves instances with an average gap of 1% and optimum ratio of 80.83%.  相似文献   

10.
    
The race to meet vital needs following sudden onset disasters leads response organizations to establish stockpiles of inventory that can be deployed immediately. These government or non-government organizations dynamically make stockpile decisions independently. Even though the value of one organization's stock deployment is contingent on others' decisions, decision makers lack evidence regarding sector capacity to assess the marginal contribution (positive or negative) of their action. To our knowledge, there exist no metrics describing the system capacity across many agents to respond to disasters. To address this gap, our analytical approach yields new humanitarian logistics metrics based on stochastic optimization models. Our study incorporates empirical data on inventory stored by various organizations in United Nations facilities and in their own warehouses to offer practical insights regarding the current humanitarian response capabilities and strategies. By repositioning inventory already deployed, the system could respond to disasters in the same expected time with a range of 7.4%–20.0% lower cost for the items in our sample.  相似文献   

11.
    
In the current paper, a model of possibilistic location-allocation is proposed for designing a multi-period bi-objective humanitarian logistics network that pursues a reduction in the total cost and maximizes the total network coverage. The model considers the inventory management of perishable relief items and the flow of affected and wounded people in pre-disaster and post-disaster phases, simultaneously. Moreover, wounded people are categorized according to the injury severity. The uncertainty associated with key parameters is also addressed. To handle the uncertainty, a fuzzy chance-constrained programming method originated in the Me measure is used. The purpose of this measure is to prevent the extreme attitudes of the decision maker by considering the combination of possibility and necessity measures and using the optimistic-pessimistic parameter. This paper presents a solution procedure derived from a fuzzy interactive programming approach and two meta-heuristic algorithms, imperialist competitive algorithm and invasive weed optimization, so as to solve the study model. As for the validation of the proposed model and solution procedures, a number of test problems have been generated. A real-life case study is also implemented to instantiate whether the proposed model is applicable or not.  相似文献   

12.
    
This paper proposes a novel two-period option contract integrated with supplier selection and inventory prepositioning. A two-stage scenario-based mixed possibilistic-stochastic programming model is developed to cope with various uncertainties. The first stage's decisions include supplier selection and capacity reservation level at each supplier/period and the level of inventory prepositioning. Furthermore, decisions regarding the time and exercised amount are made in the second stage. Applicability of the model is validated through a real case study. Finally, several sensitivity analyses are conducted to examine the effect of important parameters on the solutions to gain useful managerial insights.  相似文献   

13.
熊欣  李靖辉 《物流科技》2005,28(6):22-24
广东省现代物流正处于快速增长的阶段,如何协调物流供给与需求的矛盾,是现代物流发展过程中不可避免的问题。本文从物流的需求和供给的状况着手,分析了广东省现代物流存在供需不平衡问题的原因与表象,对匹配广东省现代物流的需求与供给提出了几条建议。  相似文献   

14.
在以国内为主,国内国际双循环的经济格局下,开拓农村市场,发展农村经济势在必行。物流业是国民经济的重要组成部分,也是发展经济的重要支撑,因此研究农村物流的需求和供给对农村物流业的发展有重要的意义。文章选取甘肃省西北部、中部、东部、东南部、西南部5个区域内的30个行政村为研究对象,采用实地调查、网络调研、访谈咨询的方法对30个行政村的物流供给和需求进行了调研。研究结果表明,甘肃省农村物流在供给上存在物流网点整体较少且区域分布不均衡等问题;在需求上存在整体需求量不足,需求结构不均衡等问题。物流发展整体水平较低。  相似文献   

15.
    
Humanitarian aid organizations are most known for their short-term emergency relief. While getting aid items to those in need can be challenging, long-term projects provide an opportunity for demand planning supported by forecasting methods. Based on standardized consumption data of the Operational Center Amsterdam of Médecins Sans Frontières (MSF-OCA) regarding nineteen longer-term aid projects and over 2000 medical items consumed in 2013, we describe and analyze the forecasting and order planning process. We find that several internal and external factors influence forecast and order planning performance, be it indirectly through demand volatility and safety markup. Moreover, we identify opportunities for further improvement for MSF-OCA, and for humanitarian logistics organizations in general.  相似文献   

16.
曾建辉  刘智勇 《物流科技》2006,29(12):44-45
本文从物流信息系统的需求分析入手,分析了物流企业信息化建设过程中的几个关键问题,从物流适作流程分析与设计两方面阐述了物流企业的信息化建设之路。  相似文献   

17.
尝试运用多元线性回归模型对河北省物流需求进行预测分析.在借鉴前人研究成果的基础上,选取研究指标,并且根据统计对数据的严格要求,选取了1990-2009年河北省统计年鉴上的相关指标作为数据来源,并对数据进行了逐步回归,以消除多重共线性,最后得出回归模型,并对模型进行了相关检验,验证模型是适合进行预测的.最后提出基于货运量是物流需求预测的关键,从三个方面提出加快河北省物流产业发展的政策建议.  相似文献   

18.
从城市发展的角度出发,分析了地下物流需求类型的各影响因素,包括产业、人口和基础设施。并以此为基础,对需求类型的宏观分类、商品类型、货物形态和配送对象等展开了系统化研究。最后以雄安新区容东片区为例,对研究成果进行了应用,以期为城市规划建设地下物流系统提供决策参考。  相似文献   

19.
首先对当前部分物流专业学生就业现状进行了问卷调研,结合当前市场对物流人才的需求现状,对应用型本科物流专业学生的培养方向及培养过程设计提出了建议。  相似文献   

20.
从物流客户需求的角度出发研究了物流企业市场定位中的市场细分、目标市场选择和相关营销策略问题,分别从国民经济其他产业的行业客户需求、区域客户需求、单个最终物流用户需求以及层次性的市场物流需求等几个角度研究了物流企业的市场定位问题,并在每个角度的研究中指出了存在的问题,给出了相关建议和理论构想.  相似文献   

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