基于分布式工厂的供应链二级分销网络生产计划优化模型

从供应链的集成和协作角度出发,提出了在多工厂、多分销商条件下二级分销网络生产计划制定的双层规划模型,模型考虑了二级网络中制造商和分销商之间的信息共享,从而降低了整个链上的费用。同时设计了启发式求解算法,并给出了一个数值例子。     

Managing Production and Distribution for Supply Chains in the Processed Food Industry

We develop and evaluate a modeling approach for making periodic review production and distribution decisions for a supply chain in the processed food industry. The supply chain faces several factors, including multiple products, multiple warehouses, production constraints, high transportation costs, and limited storage at the production facility. This problem is motivated by the supply chain structure at Amy's Kitchen, one of the leading producers of natural and organic foods in the United States. We develop an enhanced myopic two‐stage approach for this problem. The first stage determines the production plan and uses a heuristic, and the second stage determines the warehouse allocation plan and uses a non‐linear optimization model. This two‐stage approach is repeated every period and incorporates look‐ahead features to improve its performance in future periods. We validate our model using actual data from one factory at Amy's Kitchen and compare the performance of our model to that of the actual operation. We find that our model significantly reduces both inventory levels and stockouts relative to those of the actual operation. In addition, we identify a lower bound on the total costs for all feasible solutions to the problem and measure the effectiveness of our model against this lower bound. We perform sensitivity analysis on some key parameters and assumptions of our modeling approach.     

汶川特大地震灾后社区心理援助的统筹优选模式

汶川特大地震使灾区城镇和农村原有的社区基本被破坏甚至毁灭,通过对灾后社区展开问卷调查和访谈,运用SPSS统计分析软件,找出灾后社区心理援助的关键问题。在以人为本的科学发展观的统领下,依据统筹优选的思想与方法,以在最短的时间内投入最少精力,运用最有效的方法取得最佳援助效果为目的,分析灾后社区心理援助的解决思路,构建灾后社区心理援助的基本框架,提出灾后社区心理援助的统筹优选模式。该模式包括灾后心理评估体系和灾后社区心理援助过程2个方面,前者由灾后心理评估和援助效果评估2个部分组成;后者包括初期心理援助、中期心理援助和长期心理援助3个阶段,分别从援助主客体、援助内容和援助方法来进行分析研究,实现对地震灾后社区的心理援助。     

改进粒子群优化算法在电源规划中的应用

电源规划是一类复杂、非线性组合优化问题.传统的方法随着规划期的延长,考虑因素的增多,难以有效的进行优化,在实际应用中作用有限.首先,对电源规划优化问题进行了建模.然后,对于粒子群(PSO)的迭代策略进行改进,在此基础上,运用遗传粒子群(GPHA)混合优化算法进行了优化尝试.考虑到电源规划中相关参数众多,在优化过程中引入了虚拟变量对电源规划中的问题进行了简化描述;GHPA算法的适应度评价函数设计中,运用了罚函数的思想,以提高算法优化的效果.最后本文使用某省实际负荷预测和系统负荷实际数据,进行了电源规划方案优化,得到了优化后的电源规划方案,并与普通的遗传算法、粒子群算法以及传统的动态规划算法得到的结果进行了比较.比较的结果显示出了本文提出的算法在优化结果和速度方面具有明显效果.     

客户时间窗变化的物流配送干扰管理模型——基于行为的视角

针对客户时间窗变化而导致的物流配送难以顺利实施这一难题,运用干扰管理思想,以提高物流配送干扰管理决策过程的科学性为目标,结合行为科学中对人的行为感知的研究方法与运筹学中定量的研究手段,分析客户时间窗变化这类干扰事件对客户、物流配送运营商和配送业务员等受扰主体的影响,研究基于行为的扰动度量方法, 构建客户时间窗变化的字典序多目标干扰管理模型,并给出快速高效的求解方法。实例结果表明:本文方法比已有的全局重调度方法和局部重调度方法更实用--能够均衡各方的利益,获得扰动最小的调整方案。     

Linear solution schemes for Mean-SemiVariance Project portfolio selection problems: An application in the oil and gas industry

We study the Mean-SemiVariance Project (MSVP) portfolio selection problem, where the objective is to obtain the optimal risk-reward portfolio of non-divisible projects when the risk is measured by the semivariance of the portfolio׳s Net-Present Value (NPV) and the reward is measured by the portfolio׳s expected NPV. Similar to the well-known Mean-Variance portfolio selection problem, when integer variables are present (e.g., due to transaction costs, cardinality constraints, or asset illiquidity), the MSVP problem can be solved using Mixed-Integer Quadratic Programming (MIQP) techniques. However, conventional MIQP solvers may be unable to solve large-scale MSVP problem instances in a reasonable amount of time. In this paper, we propose two linear solution schemes to solve the MSVP problem; that is, the proposed schemes avoid the use of MIQP solvers and only require the use of Mixed-Integer Linear Programming (MILP) techniques. In particular, we show that the solution of a class of real-world MSVP problems, in which project returns are positively correlated, can be accurately approximated by solving a single MILP problem. In general, we show that the MSVP problem can be effectively solved by a sequence of MILP problems, which allow us to solve large-scale MSVP problem instances faster than using MIQP solvers. We illustrate our solution schemes by solving a real MSVP problem arising in a Latin American oil and gas company. Also, we solve instances of the MSVP problem that are constructed using data from the PSPLIB library of project scheduling problems.     

The multicriteria selection of products in technological diversification strategies: an application to the Spanish automotive industry based on AHP

The economic recession, the dynamism and complexity of the markets and the generalised globalisation of the world economy have forced many companies to rethink and reorganise their industrial strategies. Through identifying and taking advantage of the key technologies of a company, this work presents a new and original methodology for dealing with a general technological diversification process. The methodology, which includes an innovative cognitive perspective and its corresponding decisional tool (decision support system) has been used to select the best product in a process of technological diversification that, along with the key technologies, identifies the sub-levels consonant to the sub-technologies and applications to sectors and products. The multicriteria selection tool employed in the proposed methodology, based on the analytic hierarchy process, allows the integration of multiple scenarios, actors and criteria, both tangible and intangible. The methodology has been applied to a case study in the Spanish automotive auxiliary sector.     

基于环境角度的双层选址优化模型

本文通过建立以政府为上层,物流企业为下层的双层优化模型,对政府如何制定环境政策、企业在政府的政策指导下如何确定既保护环境,又能降低物流配送成本的选址方案进行了讨论。最后,文章通过一个实例说明了所建模型的适用性。     

Interstitial Lung Diseases in the U.S. Mining Industry: Using MSHA Data to Examine Trends and the Prevention Effects of Compliance with Health Regulations, 1996–2015

Given the recent increase in dust‐induced lung disease among U.S. coal miners and the respiratory hazards encountered across the U.S. mining industry, it is important to enhance an understanding of lung disease trends and the organizational contexts that precede these events. In addition to exploring overall trends reported to the Mine Safety and Health Administration (MSHA), the current study uses MSHA's enforcement database to examine whether or not compliance with health regulations resulted in fewer mine‐level counts of these diseases over time. The findings suggest that interstitial lung diseases were more prevalent in coal mines compared to other mining commodities, in Appalachian coal mines compared to the rest of the United States, and in underground compared to surface coal mines. Mines that followed a relevant subset of MSHA's health regulations were less likely to report a lung disease over time. The findings are discussed from a lung disease prevention strategy perspective.