On Covering Problems and the Central Facilities Location Problem

A number of variations of facilities location problems have appeared in the research literature in the past decade. Among these are problems involving the location of multiple new facilities in a discrete solution space, with the new facilities located relative to a set of existing facilities having known locations. In this paper a number of discrete solution space location problems are treated. Specifically, the covering problem and the central facilities location problem are shown to be related. The covering problem involves the location of the minimum number of new facilities among a finite number of sites such that all existing facilities (customers) are covered by at least one new facility. The central facilities location problem consists of the location of a given number of new facilities among a finite number of sites such that the sum of the weighted distances between existing facilities and new facilities is minimized. Computational experience in using the same heuristic solution procedure to solve both problems is provided and compared with other existing solution procedures.     

COMPETITIVE FACILITIES: MARKET SHARE AND LOCATION WITH RANDOM UTILITY*

ABSTRACT. A new approach is proposed for calculating the expected market share. It is assumed that consumers patronize a facility according to a utility function, selecting the facility with the highest utility value. However, consumers'ratings of the utility components are stochastic by some random distribution. Therefore, the buying power of customers located at the same point is divided among several facilities. A probability that a consumer patronizes a certain facility can be calculated. Consequently, the expected market share by competing facilities can be estimated. This calculation is more than 1,000 times faster than repeating a simulation enough times to achieve a reasonable accuracy. The distance decay calculated using the new approach is approximately exponential. A procedure for finding the optimal location anywhere in the plane for a new facility that maximizes the market share is also introduced.     

线上和线下生活服务设施可达性及其协调关系——以生鲜果蔬店铺为例

作为智慧城市的重要组成部分,“新零售”得到蓬勃发展,提供当日配送服务的“新零售”深刻影响了城市生活服务的可获取性和时空可达性。本文以南京中心城区为例,运用两步移动搜索法、耦合协调度模型等方法,探究提供当日配送生鲜果蔬服务的店铺和传统生鲜果蔬实体店空间分布特征,分析线上和线下生鲜果蔬店铺的可达性及空间协调关系。研究发现,线上生活服务遵循技术扩散假说,强化了中心城区的生活服务集聚,同时线上生活服务集聚和可达性仍受实体地理空间约束;线上生活服务有悖于效率假说,对传统生活服务的空间分异具有加强作用,整体上没有提高生活服务的供给效率和空间公平性。研究结果可为新零售影响下城市生活服务设施的配置优化提供科学依据。     

现代城市管理新模式:城市网格化管理综述

随着现代城市的快速发展,传统的城市管理手段和方式远远不能满足现代城市管理的要求,将现代城市管理理论与"数字城市"技术相结合而形成了新的城市管理模式-城市网格化管理。该模式将城市管理过程分为信息收集、案卷建立、任务派遣、任务处理、处理反馈、核实结案等环节,它采用的网格管理法、城市部件管理法、两个轴心的管理体制等是对现代城市管理模式的极大创新。     

Bi‐objective Model for Optimal Number and Size of Circular Facilities

This article presents a bi‐objective model for determining the number and size of finite size facilities. The objectives are to minimize both the average closest distance to facilities and the probability that a random line intersects facilities. The former represents the accessibility of customers, whereas the latter represents the interference to travelers. The average closest distance and the probability of intersecting facilities are derived for circular facilities randomly distributed in a circular city. The analytical expressions for the average closest distance and the probability of intersecting facilities demonstrate how the number and size of facilities affect the accessibility of customers and the interference to travelers. The model focuses on the tradeoff between the accessibility and interference, and the tradeoff curve provides planners with alternatives for the number and size of facilities.     

THE OPTIMAL LOCATIONS OF MULTIPLE BRIDGES,CONNECTING FACILITIES,OR PRODUCT VARIETIES*

ABSTRACT This paper considers the optimal locations of two or more facilities, and the optimal number of facilities, when trips are made in pairs. The results are the same as standard models of spatial competition when there is perfect matching, but not when there is random matching. The first interpretation is bridges across a river, with residential locations on one side matched perfectly or randomly to jobs on the other side. The second interpretation is connecting facilities, such as tennis courts or restaurants where pairs of consumers meet. The third interpretation is product differentiation, with husbands and wives jointly choosing from among varieties.     

广州市中心城区休闲服务设施区位类型特征的研究

以广州市中心城区为研究地域,以城市常住人口密度作为地域划分标准,引入基尼系数、带间差异系数、带别特化系数对广州市中心城区的休闲服务设施的区位类型进行划分,区分出城区均匀分布、弱城心均匀分布、城区核心集聚和城区局部集聚四类休闲服务设施的区位类型,进而对广州市中心城区的休闲服务设施的分布和微区位特征有一个初步的解读。     

中国城市社区公共服务设施配置现状与规划实施研究

城市社区服务设施分为生活服务设施、市政设施和公共服务设施三大类。在统计分析了全国城市社区建设基本情况抽样调查数据之后,重点考察了全国城市社区服务设施的覆盖率、配建规模和居民的需求现状,得出我国城市社区公共服务设施相对其它两类设施更加供不应求的结论,参照建设部和北京市、上海市、武汉市等地的城市居住区公共服务设施的设计规范,结合各种相关因素,提出了我国城市社区公共服务设施规划指标和实施建议。     

Programming Models for Facility Dispersion: The p-Dispersion and Maxisum Dispersion Problems

The p-dispersion problem is to locate p facilities on a network so that the minimum separation distance between any pair of open facilities is maximized. This problem is applicable to facilities that pose a threat to each other and to systems of retail or service franchises. In both of these applications, facilities should be as far away from the closest other facility as possible. A mixed-integer program is formulated that relies on reversing the value of the 0–1 location variables in the distance constraints so that only the distance between pairs of open facilities constrain the maximization. A related problem, the maxisum dispersion problem, which aims to maximize the average separation distance between open facilities, is also formulated and solved. Computational results for both models for locating 5 and 10 facilities on a network of 25 nodes are presented, along with a multicriteria approach combining the dispersion and maxisum problems. The p -dispersion problem has a weak duality relationship with the (p-1)-center problem in that one-half the maximin distance in the p-dispersion problem is a lower bound for the minimax distance in the center problem for (p-1) facilities. Since the p-center problem is often solved via a series of set-covering problems, the p-dispersion problem may prove useful for finding a starting distance for the series of covering problems.     

北京中低收入社区育儿人群的服务设施需求研究

服务设施需求分析是建设社区生活圈和完整社区的基础。已有研究关注服务设施供给的空间配置或评价,对服务设施需求的研究并不多见,尤其缺少对育儿人群等细分人群的研究。本文以此为切入点,讨论在二孩政策和年轻人少子化观念影响下,社区应当给予育儿人群什么样的服务设施支持。基于2017年北京公平与包容调查问卷数据,本文采用有序多分类模型分析中低收入社区居民对教育、医疗等10类设施的需求偏好。结果显示育儿人群对各类设施的需求和访问频率都超出其他人群,且相关需求存在性别差异;二孩家庭对服务设施的依赖性强于独生子女家庭,且因子女处于不同年龄段的家庭需求也有所差异。最后,本文提出了育儿人群所需服务设施的分类体系,以期为精细化社区服务设施规划提供参考。     

公共交通可达性分析方法进展

公共交通可达性拥有空间属性、时间属性、社会属性和经济属性,它是一种衡量区位价值的综合性指标,不仅可以反映城市空间特征,同时对城市中生活的人的社会经济属性和生活习惯,具有一定的解释力。为了不断适应新形势下的交通发展要求,减少环境负担,早日实现低碳绿色发展,创新公交都市规划与分析方法迫在眉睫。本文对基于个人的、基于效用的、基于基础设施的和基于位置的可达性研究进行了回顾,并归纳了七种公共交通可达性的分析方法,分别为：基于缓冲区的公共交通站点可达性、基于供需模型的公共交通面状可达性、基于网络分析法的公共交通网络可达性、基于成本栅格法的公共交通可达性、基于成本栅格与网络分析的集成法的公共交通可达性、基于高性能图形数据库的公共交通高精度可达性、基于开放地图 API 的公共交通高精度可达性。 以期为我国未来公共交通可达性的分析方法提供指引和借鉴。     

Optimal Number of Hierarchical Facilities with Failures

This article proposes a continuous approximation model for determining the number of hierarchical facilities when lower level facilities are subject to failures. The average distance from customers to the nearest open facility is derived for two types of customer behavior. The optimal number of facilities that minimizes the average distance is then obtained. The analytical expression for the optimal number of facilities demonstrates how the location of facilities, the failure probability, and the customer behavior affect the optimal hierarchy and the average distance. The result shows that introducing the hierarchy can reduce the average distance if the failure probability is small and the penalty for failing to use facilities is large. The model provides a fundamental understanding of the optimal hierarchy and is useful for designing hierarchical facility systems.     

THE OPTIMAL LOCATIONS OF BRANCH FACILITIES AND MAIN FACILITIES WITH CONSUMER SEARCH*

ABSTRACT. This paper examines the socially optimal locations of branch facilities (or small stores) and main facilities (or large stores) on a finite linear market that is uniformly populated from position 0 to position 1. Each consumer has a probability w of finding the desired service (or product) at a branch facility, and a probability 1 of finding the desired service (or product) at a main facility. Two types of consumer search are considered: phone search and visit search. Different assumptions are made about the numbers of branch facilities and main facilities (each involving one or two facilities of each type). Under visit search, the socially optimal locations of branch facilities tend to be closer to main facilities than under phone search, and this tendency is more pronounced for smaller values of w.     

The Regionally Constrained p-Median Problem

In many applications involving the location of public facilities, the activity that is being located is added to the landscape of existing public facilities and services. Further, there also exists a political and behavioral landscape of differing jurisdictions, representations, and perceptions. This paper presents a new form of the p-median problem which addresses two types of “regional” constraints that can arise in public facilities planning. A formulation is given for this specially constrained median problem along with a solution approach. Several examples are presented with computational results which indicate that this type of constrained problem could lead to better facilities planning.     

Population density and development potential in rural Zimbabwe: an assessment based on the 1969 and 1982 censuses

"Based on 1969 and 1982 census data, this paper examines the spatial association between high rural population density and development potential in Zimbabwe and its significance for national development policy. A 1982 grid cell density map was compiled on the same geographical frame as an existing 1969 density map, yielding an intercensal density change map. A land classification map and a composite map of development constraints were rasterized on the same spatial framework and subjected to computer analysis. Areas of critically high (and generally increasing) densities showed strong spatial associations with areas of severe development constraints...."     

新时期组团城市中区域性公共服务设施配置新视角--以佛山高明区为例

传统上,公共服务设施往往按照城市用地结构的等级序列自上而下集中配置。新时期,公共服务设施的准公共物品化、多元化的城市化发展模式、范围经济的出现以及信息网络和快速交通技术的发展动摇了配置公共服务设施的传统理论基础,使区域性公共服务设施可以摆脱中心城市而分散配置于其他周边地区。论文以佛山高明区为例,具体探讨了如何自下而上将区域性公共服务设施配置于次级组团城市的方法。     

健康公平理念下社区养老设施的空间分布研究——以上海市中心城区为例

提要:健康公平是当前联合国倡导的可持续发展重要目标,也是"健康中国"国策的重要战略目标.本文聚焦社区养老设施这一重要健康资源,采用基尼系数和洛伦兹曲线,比较分析上海市中心城区多种类型社区养老设施的空间分布公平性,并运用LISA方法辨析社区养老设施与老年人口的空间分布关联格局,识别存在高需求但低配置问题的供需显著失衡区域...     

上海市主城区公共服务设施网点分布的空间异质性

城市内部格局与过程空间异质性的复杂性规律成为当前人文地理研究的难点和热点。以上海市主城区为例,从结构与功能视角刻画公共服务设施的空间异质性并发现有趣现象：上海市公共服务网点呈典型“核心-边缘”圈层特点;由于占地面积、租金、服务性质等因素五大设施形成类似金融类网点的强邻近性群集聚与类似科教类网点的弱向心集聚（逆增长点）两种模式;弱向心集聚呈现空间差异扩大、空间集聚增强的新特征,与多中心空间结构会促进设施均衡化布局的构想相反;主城区边缘地带交通发展未受重视导致其运输功能空间差异增强。     

OF MISSED OPPORTUNITIES,COLONIAL LAW AND ISLAM-PHOBIA

Edward Said's works have been instructive in helping to understand the expanding influence of the West over the Orient, and the increasing apprehension this caused within colonialism. Western education was introduced to enlighten indigenous peoples, but at the same time it sowed the seeds of competition with Western hegemony. The expansion of the Netherlands East Indies in the course of the nineteenth century triggered Islamic-inspired resistance among the indigenous population, which in turn unsettled many colonial officials' peace of mind. The ongoing encroachment of the Dutch into the Malay kingdom of Riau-Lingga was one of the causes for a stricter adherence to a more orthodox form of Islam by the indigenous ruling elite. When Raja Ali Haji, a well-respected member of this elite, send in a request for funds to acquire a school building and printing facilities while referring to a government Code of Policy, Resident Netscher, the ambitious head of the regional colonial administration, must have been quite astounded. Netscher's own initiatives to establish a government school for the elite had recently been crushed, and here was a dignitary, suspected of inarticulated defiance of colonial policies, who had the nerve to request the help of the government to establish facilities that would probably aim eventually to oust government officials from the region. Surely, he would not let this (aspirant) babu take over his region! At the same time, this request shows how this Malay intellectual explored the possibilities provided by, and negotiated the boundaries set by, the colonial government.     

基于弱势群体需求的北京服务设施可达性集成研究

关注人群属性和需求,探讨服务设施供给的社会公平是新时代服务设施研究的重要议题,对于人口总量巨大、社会构成多元、社会空间分异凸显的大城市尤其如此。尽管研究某一弱势群体对单项服务设施需求的文献不断涌现,但是结合居民主观的服务设施需求偏好的可达性集成研究尚不多见。本文以北京作为案例城市,首先采用居民主观调查数据分析四类弱势群体对于公共服务设施的需求结构,然后基于POI数据,借助GIS分析这四类弱势群体服务设施需求偏好下的北京市公共服务设施综合可达性情况,且对综合可达性较差的区域进行了空间识别。本研究综合定性与定量方法,探讨主观与客观数据相匹配的可达性集成方法,可以为今后的相关研究提供借鉴,并能够对北京建设国际一流和谐宜居之都提供理论支撑。