紧急避难场所震灾服务效率的评价方法及实证——以北京市海淀区为例

紧急避难场所的服务效率评价是确保避难疏散安全性的首要科学问题。建立了紧急避难场所的识别模型,利用该模型将城市中的绿地、广场、楼间空地等所有的开敞空地识别出来,并利用地质、地理等条件对紧急避难场所自身的安全性进行了筛选,识别出城市内部的紧急避难场所,解决了紧急避难场所空间数据获取的难题。提出利用时间成本和容纳能力两个指标来综合测评紧急避难场所的服务水平。以北京市海淀区为例,评价了紧急避难场所的服务效率。评价结果显示:1海淀区紧急避难场所空间分布的集疏特征与人口空间分布的集疏特征在部分地区不相吻合。2海淀区震灾避难场所在规划时限(5 min)与实际震灾逃生时限(12 s)服务水平存在较大差异。3结合人口昼夜空间分布特征,充实度评价表明夜间紧急避难场所人均不足的现象比较明显,比较突出的是位于海淀区中部三环附近的小南庄居住区。未来,可通过提高该地区与周边无人街区或避难面积充足街区的连通性,例如通过避难标识规划的方式,来提高紧急避难场所整体的服务效率。     

城市商圈应急疏散空间布局与路径优化——以广州上下九商圈为例

针对流动人口密集和商业集中的城市商圈应急疏散的特殊性,建立了城市商圈应急疏散研究框架。该框架主要包括应急疏散需求预测、应急疏散空间适宜性评价、应急疏散路径优化3个层面。通过3σ法、灰色关联法和熵权法、GIS、OD模型等技术,将研究框架应用于广州上下九商圈。结果发现:上下九商圈疏散人口和疏散场地需求较大,目前应急避难场所不能满足区域内疏散需求;适宜性强的紧急避难场所多为学校内操场用地,但有效避难空间极易受到建筑物倒塌影响,导致场地内避难空间不足;人口密集区大部分在选定紧急避难场所500 m服务范围和疏散用时在10 min内,但城市商圈路况复杂增加了疏散成本,同时降低了疏散效率。提出了应急避难场所的空间布局和疏散路径优化建议。     

基于GIS的上海中心城区公园避难可达性研究

绿地公园对于城市防灾减灾发挥着重要应急避难作用,其空间布局的合理性直接影响到城市综合减灾效益。基于空间可达性理论和防灾避难要求,采用2SFCA模型和ArcGIS集成技术,定量研究上海中心城区公园的应急避难服务与居民避难需求之间的平衡关系。结果表明:当避难可达距离d0为500~2 000 m时,公园避难可达性呈现"中心地区弱、边缘地区强"的趋势;当d0为1 500 m时,现有城市公园避难服务范围达最大,服务人口比重达22.9%;城市公园空间布局及规模与人口分布格局不匹配是影响避难可达性空间分布差异的主要因素;适当增设学校、广场等作为避难空间以及合理设置公园的避难服务半径和规划专门的避难道路等有利于改善上海中心城区居民避难的可达性。     

基于GIS的村镇避难场所和疏散通道规划方法研究——以神农架松柏镇区为例

我国山区村镇防灾减灾意识和规划比较薄弱,不适应新时代发展要求。该文面向村镇,以避难场所和疏散通道为研究对象,从供需双向考虑出发,在总结公共设施区位模型和探讨村镇避难场所规划技术指标和评价指标的基础上,提出了基于GIS的村镇避难场所和疏散通道规划方法。首先,运用道路易损性评价方法规划疏散通道,作为避难场所规划的前提;其次,通过选址适宜性评价方法保证了避难场所的安全性和时效性,并利用现状避难场所评价方法对其进行局部优化;最后,针对现状没有或需要新增避难场所的情况,对避难人口总数和避难需求比例随时间变化进行估算,运用集合覆盖模型和最大化有容量限制覆盖模型进行新增避难场所规划,并对总体和单个避难场所进行评价。以神农架松柏镇区为例,完成了该规划方法的开发与应用,验证了其适用性与科学性。     

沈阳城市应急避难场所的识别、空间格局与服务功能

以沈阳市为例,运用高分辨率遥感影像识别城市应急避难场所,采用空间插值、波段集统计等方法刻画应急避难场所空间分布及其与人口的空间匹配性,通过栅格成本分析和加权Voronoi图等方法测算空间可达性并划分其服务区范围。研究表明:(1)沈阳市应急避难场所分布呈现出"小集聚、大分散"的基本格局,与人口分布的空间匹配性差;(2)应急避难场所可达性表现出空间异质性,大型用地对整体格局起到主要塑造作用;(3)研究区域可划分为14个较为明确的应急避难场所服务区,不同服务范围在空间上存在大小、数量和构成上的差异。最后,从城市安全视角对沈阳市应急避难场所的空间布局提出优化建议,为政府部门决策提供科学依据与政策参考。     

面向15 min生活圈的城市服务设施规划模型与实验

生活圈规划是城市公共资源均等化配置和可持续发展的重要抓手。特定城市15 min生活圈服务设施规划实践中,针对某一类公共服务,如何确定其设施数量、空间位置和服务公平性,具有诸多挑战。为回答这一问题,本文首次改进经典的设施区位问题（CFLP）为服务半径和覆盖率双重约束下的部分覆盖问题（μCFLP）,使其适用于生活圈服务设施布局规划。构造μCFLP线性规划模型,设计数学启发求解算法。按照中国城市规模划分标准,选择6个典型城市案例区域,以社区卫生服务中心为例,进行服务设施布局规划实验。结果表明：改进模型适用于城市生活圈服务设施布局规划,能够平衡服务供给成本、可及性和公平性;在人口密度较低的城市,模型对服务半径和覆盖率参数设置敏感,服务质量与效率难以兼顾,而在人口密度高的大都市,相对容易满足15 min生活圈建设标准。本文模型在面向15 min生活圈的城市服务设施规划方面具有明显的优势,一是无须事先确定设施数量,二是能够按覆盖半径与覆盖率探索最优设施布局。     

风暴洪水灾害应急疏散方法研究——以浙江省玉环县为例

以浙江省玉环县为例,对超强台风(中心气压为915hPa,最大风速61.2m·s-1)风暴洪水灾害情景下的应急疏散方法进行了系统研究。首先,基于"点-线-面"洪灾避难思想和GIS空间分析技术构建应急疏散网络模型;其次,以疏散总时间最短为目标,并综合考虑避灾容量、交通拥堵、公平分配、资源节约等因素,求解最佳疏散路径;最后,根据疏散过程动态模拟结果,进一步优化路径选择,并编制应急疏散专题预案。结果表明:如果遭受915hPa超强台风袭击,将玉环县受淹危险区内的人群完全疏散到安全地带平均耗时647s(约11min),最长疏散时间不超过45min,可满足应急避难的实际需求。该疏散预案可为完善城市安全保障系统提供科学参考。     

昆明市城区公园应急避难场所可达性研究

城市公园绿地的空间分布反映了公园绿地应急避难空间供给与居民应急避难需求的平衡关系,应急避难可达性反映了应急避难场所避难能力大小。结合防灾公园规划建设标准和空间可达性理论,采用2SFCA算法和GIS技术,研究昆明市城区公园的避难可达性。结果表明:昆明市城区公园绿地应急避难覆盖率较低,最低为1.44%,应急避难可达性整体较差;可达距离d0在2 000～2 500 m时,避难可达性呈现中间低周边高的布局;当d0为2 000 m时,可达度最大,昆明市城区公园绿地的空间分布不合理;昆明市城区公园绿地整体应急避难能力较低,不能满足居民的应急避难需求。     

河流健康评价的主评指标筛选

河流健康是近年来探讨水资源问题的一个热点,其评价指标体系正成为河流管理的目标。为了筛选出一些基本的、易于量化的主要评价指标来揭示河流健康基本状况和变化趋势,通过对1972～2010年约150篇相关文献、45个河流健康评价指标体系902项指标的整理和归纳,应用统计、层次和相关性分析法,确定各指标的被采用率,并同时综合考虑指标的重要性、普遍性、可量化性和易获得性,筛选出揭示河流生境物理、水环境、生物和水资源利用4类特征的主要指标。结果表明,有以下8个指标可作为河流健康的主评指标:河岸植被覆盖率、河流连通性、湿地保留率、径流量变化率、水质达标率、鱼类生物完整性指数、水资源利用率和流域天然植被覆盖率。     

基于微观个体避难行为的城市小微开敞空间应急救灾效能评价 ——以西安市为例

小微开敞空间能弥补避难场所在空间布局上的不足,保障居民避难的空间公平.针对西安市地震事件,通过选取典型研究区开展走访与问卷调查,对适于紧急避难的小微开敞空间进行识别,并对其容灾能力和可达性进行评价,最后基于个体避难行为微观调查,开展小微开敞空间实际应急效能实证研究.结果表明:1)从安全性和有效性角度看,研究区适于紧急避难的小微开敞空间由绿地、楼宇间和校园内空地及公共停车场组成.2)小微开敞空间容灾能力和可达性空间差异显著.其中,城中村、老旧小区、单位大院等"街区制"街区以及道路沿线区域小微开敞空间容灾能力较弱,但可达性较好,而别墅和高档住宅区等"封闭式"居住区容灾能力较强,但可达性较差.3)根据居民避难行为特征发现,广泛渗透于高密度区且居民方便接触、容易接近和感知的小微开敞空间,其实际应急效能整体较高,是居民临时避难的主要目的地.研究结果可为城市小微开敞空间识别及其灾时应急救灾能力评价提供依据.     

基于应急疏散智能体模型模拟的城市避难所空间配置——以上海市静安区为例

城市应急避难所的空间配置一直是灾害防治和城市安全研究领域的热点问题。本文以城市居民尽快地,尽少拥挤地到达满足容纳需求的应急避难所为目标,整合遥感影像数据、高精度人口分布数据、交通路网数据和专家知识等数据,综合运用智能体模型和多准则决策方法,对城市避难所空间配置开展研究。本文设计了三类与应急疏散相关的智能体：政府智能体、避难所智能体和居民智能体,来实现应急疏散的模拟,并根据模拟结果支持应急避难所的空间选址和配置。选址方法上运用了多准则决策方法和权重敏感性分析,在选址高适宜区域内选定避难所的新建方案。以新的避难所空间布局和配置为条件,执行新一轮的应急疏散模拟过程,实现选址的循环优化,从而获得最终的避难所空间配置方案。本文以上海市静安区的应急避难所空间配置分析为案例,生成了该区域应急避难所的详细空间配置方案,该方案能帮助居民在尽少拥挤风险下尽快疏散到附近的避难所。本文提出的方法充实了中国城市避难所选址的相关理论与可操作性的技术基础,为其他地区开展避难所的配置工作提供借鉴与参考。     

Integrating multi-agent evacuation simulation and multi-criteria evaluation for spatial allocation of urban emergency shelters

The timely and secure evacuation of residents to nearby urban emergency shelters is of great importance during unexpected disaster events. However, evacuation and allocation of shelters are seldom examined as a whole, even though they are usually closely related tasks in disaster management. To conduct better spatial allocation of emergency shelters in cities, this study proposes a new method which integrates techniques of multi-agent system and multi-criteria evaluation for spatial allocation of urban emergency shelters. Compared with the traditional emergency shelter allocation methods, the proposed method highlights the importance of dynamic emergency evacuation simulations for spatial allocation suitability analysis. Three kinds of agents involved in evacuation and sheltering procedures are designed: government agents, shelter agents, and resident agents. Emergency evacuations are simulated based on the interactions of these agents to find potential problems, for example, time-consuming evacuation processes and road congestion. A case study in Jing’an District, Shanghai, China was conducted to demonstrate the feasibility of the proposed method. After three rounds of simulation and optimization, new shelters were spatially allocated and a detailed recommended plan of shelters and related facilities was generated. The optimized spatial allocation of shelters may help local residents to be evacuated more quickly and securely.     

The temporal hierarchy of shelters: a hierarchical location model for earthquake-shelter planning

The problem of emergency facility location is a critical component in evacuation planning. The emergence of geographic information systems (GIS) has provided a useful operational platform to assist this issue. A previously overlooked facet is the consideration of a hierarchical structure in the placement of emergency shelters. Due to the fact that survivors' needs change over time during post-disaster evacuations, shelters have now been categorized on a temporal scale based on their functions at different evacuation phases. This article proposes a three-level hierarchical location model for optimizing the placement of earthquake shelters by taking into account this temporal variance. The article not only scrutinizes the modeling procedure but also implements the model in a planning area with many real-world details. Based on the optimization results derived from a GIS context, we have found that the quality of the earthquake response procedure is not only dependent on the placement strategy of shelters, but more importantly on the financial constraints imposed on the planning and construction of these shelters. A discussion has been proposed to balance the trade-off between budget planning and evacuation efficiency. As the first attempt to model the hierarchical configuration of emergency shelters with specific focus on evacuees' escalating sheltering demands, this article will be of great significance in helping policy makers consider both the spatial and financial aspects of the strategic placement of emergency shelters.     

Utilising volunteered geographic information to assess resident's flood evacuation shelters. Case study: Jakarta

Research on disaster response frequently uses volunteered geographic information (VGI), due to its capability to provide near real-time information during and after a disaster. It is much less commonly used in spatial planning related to disaster management. However, VGI appears to have considerable potential for use in spatial planning and offers some advantages over traditional methods. For example, VGI can capture residents' preferences in a much faster, more timely, and more comprehensive fashion than is possible with, for example, questionnaires and surveys. This research investigates the usefulness of VGI for planning flood evacuation shelters. Using Jakarta, Indonesia, as a case study, we use VGI to capture the locations of flood evacuation shelters based on residents' preferences during flood periods in 2013–2014 and 2014–2015 and compare these with the locations of official shelters. Floods frequently affect Jakarta and the city administration uses VGI in flood emergency responses. Moreover, Jakarta has been identified as having the largest number of active Twitter users among cities worldwide. Thus, Jakarta is an appropriate place to study the use of VGI for planning evacuation shelters. VGI generated by Twitter users was used to identify the shelter locations preferred by Jakarta residents, and more precisely the flood evacuees. Of 171,046 tweets using keywords relating to flood evacuation, the content of 306 tweets indicated that they had been sent from inside or near evacuation shelters. The spatial pattern showed that those tweets were sent from 215 locations, mostly located near flooded areas. The analysis further showed that 35.6% of these shelter locations preferred by residents intersected with the locations of official evacuation shelters. As a general conclusion, our study demonstrates the advantages of using VGI for spatial planning, which mainly relates to the ease of capturing community preferences over a large area.     

基于GIS的福州应急避难所空间格局评价

日益凸显的突发性自然灾害对城市应急管理提出了更高的要求,应急避难所是其重要基础设施之一.本研究利用福州市社区尺度的人口统计数据建立高精度的人口密度分布图,根据应急避难所的容纳人数与人口密度图动态缓冲区分析计算其服务能力空间范围,对研究区内21个避难所的空间格局进行评价.结果表明,福州城区避难所建设数量不足,空间分布不均,人口服务辐射能力弱.针对福州城区避难所空间分布现状,分析了主要的影响因素,对福州城区应急避难场所选址提出了进一步优化建议,认为在人口分散区的避难所应该增加数量,适当减小规模;而在人口稠密区则可增加规模适中的避难所建设.     

基于WoS和Citespace的应急避难场所知识图谱和进展分析

以近30 年Web of Science 核心数据库收录的2472 篇应急避难场所相关文献为基础,首先统计发文数量时间分布和期刊分布,然后利用Citespace可视化软件,从发文作者、机构、国家、关键词和学科方向5个方面分别进行知识图谱分析。结果表明：近30年来应急避难场所研究发文呈现由缓慢探索、稳步发展向高速发展的阶段;发文期刊主要为自然灾害类、紧急医学类、工程技术类;研究作者群较多,学术交流较为紧密;美国和中国为发文量最多的国家;路易斯安那州立大学和中国科学技术大学是主要的发文机构;从关键词发现应急避难场所目标人群主要围绕灾害救援和社会弱势群体,研究视角从单一问题和事件开始向综合系统演变,研究方法从定性的方法模型转向动力机制和信息系统开发,研究内容则注重多学科交叉和微观尺度、重视案例实证和信息共享和强调应急避难场所管理;学科方向主要为工程学和公共环境与健康两个学科。在建设韧性城市的背景下,可借鉴国际经验来构建中国应急避难场所研究体系和管理。     

Factors Affecting Evacuation Behavior: The Case of 2007 Cyclone Sidr,Bangladesh

Cyclone Sidr, a Category 4 storm, struck the southwestern coast of Bangladesh on 15 November 2007. Despite early cyclone warnings and emergency evacuation orders for coastal residents, thousands of individuals stayed in their homes. This study examines Sidr victims’ responses to cyclone warnings and evacuation orders, and explores the factors that would explain why the victims did or did not comply with the orders. Based on survey data collected from 277 Sidr survivors living in the four most severely impacted coastal districts, this study found that more than 75 percent of all respondents were aware of the cyclone warnings and evacuation orders before Sidr's landfall. Despite the efforts of the Bangladesh government, there were lapses in cyclone warnings and evacuation procedures. Field data also reveal several reasons cited by respondents for not complying with evacuation orders. Multivariate analyses of survey data show that trust in warning messages was the most important determinant in the decision to seek refuge in safer shelters, followed by distance to nearest shelter and annual level of education. Several recommendations have been made to improve cyclone warnings and the use of public shelters for similar future events.     

基于生活圈理论的合肥市城市养老服务设施空间配置合理性研究

基于生活圈理论,构建了城市养老服务设施空间配置合理性评价标准,运用GIS空间分析方法,从城市、行政区及街道等不同空间层面对合肥市城市养老服务设施空间分布特征及配置合理性进行分析。研究发现：1）合肥市城市养老供给以社区养老服务为主要类型,城市养老服务设施建设数量和体量在4个行政区间存有较大差异;2）合肥市城市养老服务设施空间分布、配置合理性均由城市中心向外围地区呈圈层式递减,城市新区是养老服务供给的薄弱地段;3）合肥市城市养老服务设施空间配置合理性在街道层面差异更显著,覆盖率相似街道呈现明显的空间聚集特征。     

A multicriteria spatial decision support system for solving emergency service station location problems

Earthquakes occurring in urban areas constitute an important concern for emergency management and rescue services. Emergency service location problems may be formulated in discrete space or by restricting the potential location(s) to a specified finite set of points in continuous space. We propose a Multicriteria Spatial Decision Support System to identify shelters and emergency service locations in urban evacuation planning. The proposed system has emerged as an integration of the geographical information systems (GIS) and the multicriteria Decision-Making method of Preference Ranking Organization Method for Enrichment Evaluation IV (PROMETHEE IV). This system incorporates multiple and often conflicting criteria and decision-makers’ preferences into a spatial decision model. We consider three standard structural attributes (i.e., durability density, population density, and oldness density) in the form of spatial maps to determine the zones most vulnerable to an earthquake. The information on these spatial maps is then entered into the ArcGIS software to define the relevant scores for each point with regards to the aforementioned attributes. These scores will be used to compute the preference functions in PROMETHEE IV, whose net flow outranking for each alternative will be inputted in ArcGIS to determine the zones that are most vulnerable to an earthquake. The final scores obtained are integrated into a mathematical programming model designed to find the most suitable locations for the construction of emergency service stations. We demonstrate the applicability of the proposed method and the efficacy of the procedures and algorithms in an earthquake emergency service station planning case study in the city of Tehran.     

A comparison of scenario-based hybrid bilevel and multi-objective location-allocation models for earthquake emergency shelters: a case study in the central area of Beijing,China

The accurate location and allocation of disaster emergency shelters are key components of effective urban planning and emergency management. Various models have been developed to solve the location-allocation problem, but gaps remain with regard to model realism and associated applicability. For the available location and allocation models of earthquake emergency shelters, uncertainty with respect to earthquake hazard, population exposure, rate of damage to buildings and the effects of evacuee behavior are often neglected or oversimplified. Moreover, modifying the models can be an alternative means of improving the solution quality when the optimization algorithm has difficulty coping with a complex, high-dimensional problem. This article develops a scenario-based hybrid bilevel model that addresses the concerns related to high-dimensional complexity and provides a higher degree of realism by incorporating the uncertainties of population dynamics and earthquake damage scenarios into location-allocation problems for earthquake emergency shelters. A modified particle swarm optimization algorithm combined with a simulated annealing algorithm was applied to derive solutions using the hybrid bilevel model and a conventional multi-objective model, and the solutions obtained using the two models were then compared. The novel features of the study include the hybrid bilevel model that considers the dynamic number of evacuees and its implementation for earthquake emergency shelter location and allocation. The results show that the solutions significantly differ between daytime and nighttime. When applied to the multi-objective model, the optimization algorithm is time consuming and may only find the local optima and provide suboptimal solutions in the considered scenarios with more evacuees. By contrast, the hybrid bilevel model shows more desirable performance because it significantly reduces the dimensionality of the location-allocation problem based on a two-step-to-reach approach. The proposed hybrid bilevel model is proven to be useful for optimal shelter allocation, and the presented results can be used as a reference for balancing the interests of the government and residents during the planning of shelters in Beijing.