体制变迁与供需失衡:铁路春运运力不足的结构性困境研究

铁路春运"一票难求"的表面原因是铁路运力不足,而运力不足的背后是深层次的社会问题,是人口流动背景下的春运客运需求激增、垄断体制下的铁路发展困境,以及因春节情结和公众选择偏好引发的放大效应等结构性困境。     

Taking Stock of Neighbourhood Planning in England 2011–2016

Neighbourhood planning (NP) as enabled by the 2011 Localism Act in England has precipitated a considerable literature discussing its potential, limitations and likely shortcomings referenced against government rhetoric and the reporting of initial experiences of the process. This paper provides an overview of the current literature on neighbourhood planning and sets out how it has been received and practised across England drawing on empirical evidence. The extent of take-up and the experience of those involved in the first five years of neighbourhood planning is used to consider how community-led planning may be designed and used following operational principles of inclusivity, capacity-building and adding value.     

园林景观规划设计与地域文化

地域文化的缺失导致园林景观规划设计及其实施效果呈现雷同的趋势,通过提出规划设计中地域文化的范畴和意义,强调了体现地域文化在规划设计中的重要性。借助三个实际的规划设计案例从宏观角度提出规划概念应与地域自然特点、人文特点等要素有机结合,从而从微观角度提出设计可采用保留、抽取、融合、再现等手法来体现地域文化。此外,在规划设计中运用地域文化应该注意契合性、创新性、烂漫性及可实施性等的几个方面的问题。     

Joint product assortment,inventory and price optimization to attract loyal and non-loyal customers

In this paper, we analyze the emerging retail practice of carrying a combined product assortment consisting of both regular “standard” products and more fashionable and short-lived “special” products. The purpose of this practice is to increase store traffic by attracting heterogeneous classes of customers, which drives up sales of standard products due to the potential cross-selling effect. Customers who are primarily attracted by special products will also buy some standard products. In this context, we analyze three decisions that are crucial for a retailer׳s commercial success: the product assortment, the inventory levels and the pricing. We propose an optimization model and an iterative heuristic to analyze the trade-offs between the combined product assortment, the inventory level and the price per product when there is limited shelf space. Using numerical experiments, we show that our heuristic can be trusted and that its accuracy improves when the number of products increases. Our findings indicate that to attract more customers for standard products, a retailer may benefit from carrying low priced special products which, if considered in isolation, would be non-profitable. As the cross-selling effect decreases, a retailer should focus more on the standard assortment by increasing its size and decreasing the prices. However, introducing special products and ignoring the cross-selling effect may decrease a retailer׳s profitability. We show that the introduction of special products involves more than just choosing the right specials for non-loyal customers but impacts the global assortment planning, the standard products and the products pricing.     

Tactical production and distribution planning with dependency issues on the production process

Tactical production-distribution planning models have attracted a great deal of attention in the past decades. In these models, production and distribution decisions are considered simultaneously such that the combined plans are more advantageous than the plans resolved in a hierarchical planning process. We consider a two-stage production process, where in the first stage raw materials are transformed into continuous resources that feed the discrete production of end products in the second stage. Moreover, the setup times and costs of resources depend on the sequence in which they are processed in the first stage. The minimum scheduling unit is the product family which consists of products sharing common resources and manufacturing processes. Based on different mathematical modelling approaches to the production in the first stage, we develop a sequence-oriented formulation and a product-oriented formulation, and propose decomposition-based heuristics to solve this problem efficiently. By considering these dependencies arising in practical production processes, our model can be applied to various industrial cases, such as the beverage industry or the steel industry. Computation tests on instances from an industrial application are provided at the end of the paper.     

Community Resilience and Decision Theory Challenges for Catastrophic Events

Extreme and catastrophic events pose challenges for normative models of risk management decision making. They invite development of new methods and principles to complement existing normative decision and risk analysis. Because such events are rare, it is difficult to learn about them from experience. They can prompt both too little concern before the fact, and too much after. Emotionally charged and vivid outcomes promote probability neglect and distort risk perceptions. Aversion to acting on uncertain probabilities saps precautionary action; moral hazard distorts incentives to take care; imperfect learning and social adaptation (e.g., herd‐following, group‐think) complicate forecasting and coordination of individual behaviors and undermine prediction, preparation, and insurance of catastrophic events. Such difficulties raise substantial challenges for normative decision theories prescribing how catastrophe risks should be managed. This article summarizes challenges for catastrophic hazards with uncertain or unpredictable frequencies and severities, hard‐to‐envision and incompletely described decision alternatives and consequences, and individual responses that influence each other. Conceptual models and examples clarify where and why new methods are needed to complement traditional normative decision theories for individuals and groups. For example, prospective and retrospective preferences for risk management alternatives may conflict; procedures for combining individual beliefs or preferences can produce collective decisions that no one favors; and individual choices or behaviors in preparing for possible disasters may have no equilibrium. Recent ideas for building “disaster‐resilient” communities can complement traditional normative decision theories, helping to meet the practical need for better ways to manage risks of extreme and catastrophic events.     

基于分权视角的城市规划管理体制模式及改革建议

关于我国的城市规划管理权限一直存在＂集中＂与＂放权＂的讨论,并且城市规划管理体制也存在差异。通过对全国部分城市的规划管理体制进行梳理,从市、区（县、市）两级分权视角总结出我国城市规划管理体制中的＂垂直型＂、＂半垂直型＂和＂非垂直型＂三种典型模式,分别以南京、北京和上海为案例分析三种规划管理体制典型模式的主要特点和事权划分,并对其各自的优缺点进行比较,最后提出我国城市规划管理体制改革的若干建议,包括将规划决策权＂上收＂与实施管理重心＂下移＂、建立＂市—区—镇（街）＂三级规划管理机构体系、整合市区两级规划部门内部机构设置形成＂大处室＂和＂大科室＂以及完善城市规划委员会制度等。     

考虑储存成本的集装箱公铁联运路径优化

联运企业的效益受运输路径和运输方式的影响。如何降低联运成本、提高联运企业的效益,已成为学术研究的重中之重。针对集装箱公铁联运路径优化问题,以运输成本、换装成本、储存成本、时间惩罚成本构成的运输总成本为目标函数,建立集装箱公铁联运路径优化模型,考虑运输时间限制、班期限制、节点储存成本,得出使运输总成本最低的运输路径及运输方式,并利用算例验证模型的有效性。     

Backward capacity-filtering for electronics Fabs

In electronics Fabs such as semiconductor Fabs and liquid crystal display (LCD) Fabs, which are capital-intensive, finite-capacity planning is critical to achieving full-capacity production and on-time production. However, existing finite-capacity planning methods do not adequately reflect the actual capacity profiles of an electronics Fab. In this paper, we propose a new Fab-level capacity-filtering procedure to generate finite-capacity plan: a backward capacity-filtering procedure for generating finite-capacity release plan. When developing the Fab-level filtering procedures, we use stage-level capacity-filtering algorithms as a key building block. In this study, we enhance the previous capacity-filtering algorithms proposed by one of the authors in order to facilitate the practical requirements of electronics Fabs. We apply the proposed capacity-filtering method to a modern LCD–TFT Fab in Korea. Performance analyses demonstrate that the proposed method is superior to existing methods.     

The place of informality and illegality in planning education in Nigeria

This paper discusses the extent to which topical planning issues of informality and illegality are incorporated into the educational curricula in Nigerian planning schools. Given the scale and enormity of informal and illegal settlements in Nigeria and other African cities, these issues should be emphasized in the education and training of planning professionals. Yet, few curricula in Nigerian planning schools, including the Nigerian Town Planners Registration Council’s professional curriculum, incorporate informal urban issues. The paper recommends an educational interventionist approach based on recognition of the potential of indigenous knowledge as a means of producing critical and reflective planning graduates who possess the competencies to deal with contemporary settlement challenges. It presents the institutional landscape for planning education and the processes of planning curricular reform and accreditation with a view to revitalizing planning education in Nigeria.