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1.
针对"互联网+大数据"优化电商配送服务质量问题,明确不同收货方的质量需求稳定性,引导电商根据收货方不同质量敏感性提供相对精准服务,提升配送服务质量。模拟投票结果的形成过程聚类得到收货方对服务质量偏好的记忆性特征:(1)"无记忆"型收货方;(2)"记忆"型收货方;(3)"不确定"型收货方;(4)收货方总体。进一步推导不同规划类型求解空间,设计得到"无记忆"型收货方动态规划精确求解方法,及其他三种类型近似求解粒子群算法。研究过程中,配送资源质量感知度被嵌入到模型约束;"无记忆"型收货方的质量需求规划问题转化为零库存策略最优解问题,进而证明存在精确解;"记忆"型收货方呈现出对质量感知的累积;"不确定"型收货方模型通过赋值即可得总体收货方表达式。结果表明:数据驱动研究框架借助大数据资源,使得电商更易通过收货方的质量偏好设计更加匹配的配送方案;不确定服务需求得到有效满足,投入成本的利用率更高;通过特征分类的方式,尽可能地抽取能够精确最优化的部分,缩小NP范围,提高整体求解的精确度。  相似文献   
2.
Managing risk in infrastructure systems implies dealing with interdependent physical networks and their relationships with the natural and societal contexts. Computational tools are often used to support operational decisions aimed at improving resilience, whereas economics‐related tools tend to be used to address broader societal and policy issues in infrastructure management. We propose an optimization‐based framework for infrastructure resilience analysis that incorporates organizational and socioeconomic aspects into operational problems, allowing to understand relationships between decisions at the policy level (e.g., regulation) and the technical level (e.g., optimal infrastructure restoration). We focus on three issues that arise when integrating such levels. First, optimal restoration strategies driven by financial and operational factors evolve differently compared to those driven by socioeconomic and humanitarian factors. Second, regulatory aspects have a significant impact on recovery dynamics (e.g., effective recovery is most challenging in societies with weak institutions and regulation, where individual interests may compromise societal well‐being). And third, the decision space (i.e., available actions) in postdisaster phases is strongly determined by predisaster decisions (e.g., resource allocation). The proposed optimization framework addresses these issues by using: (1) parametric analyses to test the influence of operational and socioeconomic factors on optimization outcomes, (2) regulatory constraints to model and assess the cost and benefit (for a variety of actors) of enforcing specific policy‐related conditions for the recovery process, and (3) sensitivity analyses to capture the effect of predisaster decisions on recovery. We illustrate our methodology with an example regarding the recovery of interdependent water, power, and gas networks in Shelby County, TN (USA), with exposure to natural hazards.  相似文献   
3.
Abstract

Resource scheduling for emergency relief operations is complex as it has many constraints. However, an effective allocation and sequencing of resources are crucial for the minimization of the completion times in emergency relief operations. Despite the importance of such decisions, only a few mathematical models of emergency relief operations have been studied. This article presents a bi-objective mixed integer programming (MIP) that helps to minimize both the total weighted time of completion of the demand points and the makespan of the total emergency relief operation. A two-phase method is developed to solve the bi-objective MIP problem. Additionally, a case study of hospital network in the Melbourne metropolitan area is used to evaluate the model. The results indicate that the model can successfully support the decisions required in the optimal resource scheduling of emergency relief operations.  相似文献   
4.
Not only ETO (Engineering to Order), but even serial production industry should know how to deal with projects and their schedule: plant commissioning, shutdown, introducing new products and similar circumstances should be managed with adequate planning and resource allocation techniques to create a schedule useful in decision making during the execution. The current complex reality, with evolving technologies and fierce pressure to reach the market as soon as possible, pushes the project managers to use more advanced techniques than waterfall planning, such as agile or lean. It also requires them to take a holistic view and manage concurrent tasks in complex projects. The contributions of this paper are two: the proposal to control specific parallel groups of waterfall activities under uncertain environments, which can lead to iterations and reworks, as a single concurrent Activity Managed by Kanban Methods (AMKM). This activity can be subsequently embedded into traditional scheduling approaches as CPM-PERT. The second contribution is the feasibility of its application in industrial environments due to the affordability of simulation software. Two use cases are shown as evidence. It is not a disruptive proposal, but a kaizen action based on very mature technologies. Finally, it is suggested some improvements to be implemented in Project Management Software due to this ‘kaizen’ proposal.  相似文献   
5.
随着我国房地产市场由卖方市场逐渐过渡到买方市场,房地产投资运作模式由作坊生产式投资模式逐渐向社会化大生产式投资模式椎进。  相似文献   
6.
基于GPS/GSM/GIS集成的动态车辆优化调度的研究   总被引:1,自引:0,他引:1  
目前,GPS(全球定位系统)、GSM(数字蜂窝移动通信系统)和GIS(地理信息系统)都是成熟的商业技术。运用这些技术,再结合Dijstra最短路和贪心算法,可合理实现单配送中心、非满载送货条件下的车辆优化调度,提高配送效率。  相似文献   
7.
反梯度推进:西部产业升级的一种思路   总被引:1,自引:0,他引:1  
反梯度推进理论的核心内容强调 :落后地区要根据自己的实际情况 ,直接引进世界最先进的技术 ,发展自己的高新技术 ,带动传统产业实现超越发展。近几年 ,我国提出的西部大开发战略 ,其实质就是要解决中国区域经济的均衡协调发展问题 ,实现区域经济的跨越式发展。而实现结构优化和产业升级则是根本出路。在这方面 ,反梯度推进理论为我国西部大开发过程中的产业升级提供了非常重要的启示。  相似文献   
8.
While much used in practice, latent variable models raise challenging estimation problems due to the intractability of their likelihood. Monte Carlo maximum likelihood (MCML), as proposed by Geyer & Thompson (1992 ), is a simulation-based approach to maximum likelihood approximation applicable to general latent variable models. MCML can be described as an importance sampling method in which the likelihood ratio is approximated by Monte Carlo averages of importance ratios simulated from the complete data model corresponding to an arbitrary value of the unknown parameter. This paper studies the asymptotic (in the number of observations) performance of the MCML method in the case of latent variable models with independent observations. This is in contrast with previous works on the same topic which only considered conditional convergence to the maximum likelihood estimator, for a fixed set of observations. A first important result is that when is fixed, the MCML method can only be consistent if the number of simulations grows exponentially fast with the number of observations. If on the other hand, is obtained from a consistent sequence of estimates of the unknown parameter, then the requirements on the number of simulations are shown to be much weaker.  相似文献   
9.
本文给出一类非均匀弦的横向振动的最佳控制,推广了P C Park的结果。这一结果同样适用于同类型振动问题。  相似文献   
10.
将无抵触理论应用于公共英语教学,可以对外语学习活动进行设计,使学习者水平与任务的难度相当、培养语言学习兴趣、加强师生交流、确保学习者获得学习主动权等,使其在学习过程中体验到巨大乐趣,进入以注意力高度集中和全身心投入为特征的无抵触心理状态,提高学习效率。  相似文献   
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