Application of fuzzy optimization model in the evaluationof urban flood-waterloggedvulnerabilitybased on the synthetic weight ofgame theory

The evaluation of urban flood-waterlogged vulnerability is very important to the safety of urban flood control. In this paper, the evaluation of consolidated index is used. Respectively, AHP and entropy method calculate the subjective and objective weight of the evaluation indicators, and combine them by game theory. So we can obtain synthetic weight based on objective and subjective weights. The evaluation of urban flood-waterlogged vulnerability as target layer, a single variable multi-objective fuzzy optimization model is established. We use the model to evaluate flood-waterlogged vulnerability of 13 prefecture-level city in Hunan, and compare it with other evaluation method. The results show that the evaluation method has certain adaptability and reliability, and it＇ s helpfid to the construction planning of urban flood control.

Climate change vulnerability assessment in the new urban planning process in Tanzania

Climate change vulnerability assessment is an essential tool for identifying regions that are most susceptible to the impacts of climate change and designing effective adaptation actions that can reduce vulnerability and enhance long-term resilience of these regions.This study explored a framework for climate change vulnerability assessment in the new urban planning process in Jangwani Ward,Tanzania.Specifically,taking flood as an example,this study highlighted the steps and methods for climate change vulnerability assessment in the new urban planning process.In the study area,95 households were selected and interviewed through purposeful sampling.Additionally,10 respondents(4 females and 6 males)were interviewed for Focus Group Discussion(FGD),and 3 respondents(1 female and 2 males)were selected for Key Informant Interviews(KII)at the Ministry of Lands,Housing and Human Settlements Development.This study indicated that climate change vulnerability assessment framework involves the assessment of climatic hazards,risk elements,and adaptive capacity,and the determination of vulnerability levels.The average hazard risk rating of flood was 2.3.Socioeconomic and livelihood activities and physical infrastructures both had the average risk element rating of 3.0,and ecosystems had the average risk element rating of 2.9.Adaptive capacity ratings of knowledge,technology,economy or finance,and institution were 1.6,1.9,1.4,and 2.2,respectively.The vulnerability levels of socioeconomic and livelihood activities and physical infrastructure were very high(4.0).Ecosystems had a high vulnerability level(3.8)to flood.The very high vulnerability level of socioeconomic and livelihood activities was driven by high exposure and sensitivity to risk elements and low adaptive capacity.The study recommends adoption of the new urban planning process including preparation,planning,implementation,and monitoring-evaluation-review phases that integrates climate change vulnerability assessment in all phases.

Vulnerability of Large City and Its Implication in Urban Planning: A Perspective of Intra-urban Structure

Vulnerability is a new field and analytical tool in the study of urban safety. Analysis and assessment of vulnerability provide a new basis for urban planning. This study constructed a quantitative index system for assessing vulnerability, based on the city′s sensitivity and emergency response capacity. City size, density, and spatial form influence a city′s sensitivity to crises and risks, to which vulnerability is positively related. Levels of socio-economic development, infrastructures, and emergency management contribute to a city′s emergency response capacity, with which vulnerability is inversely associated. Vulnerability of 19 large Chinese cities was assessed. Harbin and Shenzhen demonstrated the highest and lowest vulnerability among 19 cities, while Beijing, Shanghai and Guangzhou ranked the 5th, the 9th and the 12th. Spatially, northern cities tended to be more vulnerable than southern cities. And the differences in vulnerability among cities were explored based on cities′ physical geography conditions, level of socioeconomic development, infrastructures, regional status, history of disaster, history of urban planning and development, government policies, etc.

Seismic vulnerability assessment of urban buildings and traffic networks using fuzzy ordered weighted average

Urban buildings and urban traffic network are considered as the vital arteries of cities which have particular effects especially after the crisis in the search and rescue operations. The aim of this study is to determine the vulnerability of urban areas especially, buildings and traffic networks using multicriteria geographic information systems and decisionmaking methods. As there are many effective criteria on the seismic vulnerability that they have uncertain and vague properties, the method of this paper is applying fuzzy ordered weighted average(OWA) to model the seismic vulnerability of urban buildings and traffic networks in the most optimistic and pessimistic states. The study area is district 6 of Tehran that is affected by the four major faults, and thus will be threatened by the earthquakes. The achieved results illustrated the vulnerability with different degrees of risk levels including very high, high, medium, low and very low. The results show that in the most optimistic case 14% and in the pessimistic case 1% of buildings tolerate in very low vulnerability. The vulnerability of urban street network also indicates that in the optimistic case 12% and in the pessimistic case at most 9% of the area are in appropriate condition and the North and NorthEast of the study area are more vulnerable than South of it.

Seismic vulnerability assessment of urban buildings using the rough set theory and weighted linear combination

Seismic vulnerability assessment of urban buildings is among the most crucial procedures to post-disaster response and recovery of infrastructure systems.The present study proceeds to estimate the seismic vulnerability of urban buildings and proposes a new framework training on the two objectives.First,a comprehensive interpretation of the effective parameters of this phenomenon including physical and human factors is done.Second,the Rough Set theory is used to reduce the integration uncertainties,as there are numerous quantitative and qualitative data.Both objectives were conducted on seven distinct earthquake scenarios with different intensities based on distance from the fault line and the epicenter.The proposed method was implemented by measuring seismic vulnerability for the seven specified seismic scenarios.The final results indicated that among the entire studied buildings,71.5%were highly vulnerable as concerning the highest earthquake scenario(intensity=7 MM and acceleration calculated based on the epicenter),while in the lowest earthquake scenario(intensity=5 MM),the percentage of vulnerable buildings decreased to approximately 57%.Also,the findings proved that the distance from the fault line rather than the earthquake center(epicenter)has a significant effect on the seismic vulnerability of urban buildings.The model was evaluated by comparing the results with the weighted linear combination(WLC)method.The accuracy of the proposed model was substantiated according to evaluation reports.Vulnerability assessment based on the distance from the epicenter and its comparison with the distance from the fault shows significant reliable results.

A Systemic Approach to Evaluate the Flood Vulnerability for an Urban Study Case in Southern Italy

Currently, the urban flooding is one of the most concerning problems in hydraulic protection, both for the enormous number of people and the different elements (buildings, roads, vehicles, and so on) potentially exposed to risk, as well as the complexity of the territory at issue. At the practical level, vulnerability indicators are often predictably too narrow in their coverage of aspects of vulnerability. An important need remains to produce more conceptually informed vulnerability indicators or parameters and more satisfactory operational tools to assess weaknesses and resilience in coping with natural risks. In this paper, we present an innovative methodology that adopts a systemic approach to evaluate the vulnerability due to a flood scenario. The operative efficiency of the proposed GIS tool is validated in pilot application site, i.e. an urban area in Puglia Region, Southern Italy, on the basis of, studies surveys and damages carried out from a recent flood event occurred in the area. The model evaluates the direct structural damages and explores the potential operating conditions of the road network in case of the flood event. The resulting vulnerability assessment tool can guide evaluators towards a comprehensive understanding of strengths and fragilities of a territory and community where a flood occurs embedding and integrating as much as possible the multifaceted and articulated nature of an urban system.

Urban Vulnerabilities in the Kathmandu Valley, Nepal: Visualizations of Human/Hazard Interactions

Excessive unplanned urban growth leads to many vulnerabilities and impacts on urban environments to varying degrees. However, the majority of the extant literature focuses on the problems related to location and socioeconomic conditions, rather than vulnerability processes and related environmental degradation. This paper analyzes the scope of urban vulnerabilities for five rapidly urbanizing and highly-congested cities in the Kathmandu Valley, Nepal. First, the historic context of the Valley’s uncontrolled urbanization sets the scene. Second, the optic is narrowed to focus upon the geographical features of the resultant urbanized Valley landscape that includes spatial arrangements and of houses, population densities, road networks, vehicular densities, garbage problems, and available open spaces. Additionally, seismic vulnerabilities in the urban areas are also considering in this examination. Third, three-dimensional visualizations of selected urban locations are presented to differentiate between vulnerable and relatively safe locations. The intent of this research is to contribute to the methodological understanding of human/hazards interactions in rapidly urbanizing cities of the Third World, which share similar socioeconomic conditions and environmental con-texts.

Analysis of the impact of large scale seismic retrofitting strategies through the application of a vulnerability-based approach on traditional masonry buildings

The buildings＇ capacity to maintain minimum structural safety levels during natural disasters, such as earthquakes, is recognisably one of the aspects that most influence urban resilience. Moreover, the public investment in risk mitigation strategies is fimdamental, not only to promote social and urban and resilience, but also to limit consequent material, human and environmental losses. Despite the growing awareness of this issue, there is still a vast number of traditional masonry buildings spread throughout many European old city centres that lacks of adequate seismic resistance, requiring therefore urgent retrofitting interventions in order to both reduce their seismic vulnerability and to cope with the increased seismic requirements of recent code standards. Thus, this paper aims at contributing to mitigate the social and economic impacts of earthquake damage scenarios through the development of vulnerability-based comparative analysis of some of the most popularretrofitting techniques applied after the 1998 Azores earthquake. The influence of each technique individually and globally studied resorting to a seismic vulnerability index methodology integrated into a GIS tool and damage and loss scenarios are constructed and critically discussed. Finally, the economic balance resulting from the implementation of that techniques are also examined.

Vulnerability to Landslides in the City of Sao Paulo

The City of Silo Paulo is the largest urban occupation in Brazil, covering 1,500 km^2. Its population is approximately 12 million inhabitants, 12% of them living in subnormal agglomerates, the IBGE （Brazilian Agency for Statistics and Geography） denomination for informal settlements, mostly located in fiver floodplain areas or top of hills. The extreme high level of soil sealing and high slopes have a fundamental role to explain the increase the risks of mass movements or landslides, related to precipitation magnitude and duration. This article presents the construction of curves coupling landslides occurrences and precipitation based on the data analysis of different basins in the city of Sao Panlo, considering also the probability and duration of the rainfall event in order to establish a vulnerability index to estimate the vulnerability category of an specific area. Based on the data analysis of instantaneous radar rain records for seven extreme rainfall events where landslides occurrences records were available, it was possible to plot sigmoid curves linking the number of occurrences with the event probability in terms of return period.

The Role of the Spatial Network in Urban Disaster Risk Variations:Reimagining the Notion of Spatial Vulnerability at the Urban Scale

The notion of“spatial vulnerability”is present in most disaster studies with a strong geographical connotation and accordingly is adopted at all scales,including the urban.While enabling mapping and visualizing risk patterns at macroscales,this geocentric foundation fails to capture disaster risk dynamics associated with the urban spatial network—an element that plays a significant role in the everyday and emergency functioning of cities,enabling users'movement and interaction.Yet,urban vulnerability assessment overlooks this aspect and thus leaves urban disaster risk mechanisms partially unexplored.This study investigated the role of the network of urban public open spaces(UPOS)in the creation and progression of urban disaster risk in earthquake-prone settlements.Through a multimethod approach that integrates quantitative and qualitative methods and explores spatial configuration,planning policies,and practices of use of UPOS in everyday and emergency scenarios,our study demonstrated that UPOS configuration plays an active role in urban disaster risk.Urban public open spaces impact risk by influencing the exposure of pedestrians and their capacity for self-protection.The study further reconceptualized spatial vulnerability at the urban scale,as the fraction of vulnerability associated to the spatial network,highlighting the interplay of planning policies and spatial practices in its production and progression.Our findings make the notion of spatial vulnerability less ambiguous at the urban scale,by viewing the variable as an imbalance in capacities and exposure that generates spatially unsafe conditions.This refined conceptualization of spatial vulnerability becomes a lens for a more granular approach to urban disaster risk reduction and city planning by identifying and integrating sociospatial considerations.

Simulating Sustainable Urban Development by Incorporating Social-ecological Risks into a Constrained CA Model

A key solution to urban and global sustainability is effective planning of sustainable urban development, for which geo-techniques especially cellular automata(CA) models can be very informative. However, existing CA models for simulating sustainable urban development, though increasingly refined in modeling urban growth, capture mostly the environmental aspect of sustainability. In this study, an adaptable risk-constrained CA model was developed by incorporating the social-ecological risks of urban development. A three-dimensional risk assessment framework was proposed that explicitly considers the environmental constraints on, system resilience to, and potential impacts of urban development. The risk-constrained model was then applied to a case study of Sheyang County, Jiangsu Province in the eastern China. Comparative simulations of urban development in four contrasting scenarios were conducted, namely, the environmental suitability constrained scenario, the ecological risk constrained scenario, the social risk constrained scenario, and the integrated social-ecological risk constrained scenario. The simulations suggested that considering only environmental suitability in the CA simulation of urban development overestimated the potential of sustainable urban growth, and that the urbanization mode changed from city expansion that was more constrained by social risks to town growth that was more constrained by ecological risks. Our risk-constrained CA model can better simulate sustainable urban development; additionally, we provide suggestions on the sustainable urban development in Sheyang and on future model development.

Management of Water Supply Reservoirs under Uncertainties in Arid and Urbanized Environments

Simulation and evaluation study of the three Water Supply Reservoirs in the Notwane Catchment was undertaken using a hybrid modelling approach linking the reservoir simulation model (HEC-ResSim) model and a reservoir reliability analysis (RRA) model. It was used to understand the management challenges and operation aspects facing the recent failure and declining water supply from three reservoirs in Gaborone and the surrounding areas, a typical arid and urbanized environment where current and future water supply reliability is challenged by both climate and anthropologic factors. The model was analysed for a calibration period of ten years (1993-2002), and verification period of eight years (2003-2010) and then simulation period of 40 years (2011-2050). The simulation period up to the year 2050 was considered to include the year 2035, which is the planning horizon of the National Water Master Plan. The model calibration and verification results are satisfactorily accepted for the fit of the daily water levels. The values of R2 and the Nash-Sutcliffe model efficiency criteria for the calibration period, are 0.81/60%, 0.62/27% and 0.54/39% for the Bokaa dam, Gaborone dam and Nnywane dam, respectively. Various scenarios were considered to determine the plausible sources of uncertainty and challenge for operation and management of the water supply reservoirs considering: population and urbanization, sedimentation, seepage, climate change, operational aspects, among others. From the RRA model, it was found that Gaborone dam, which is the largest of the three dams has lower resilience, lower reliability and higher vulnerability associated with increasing population pressures, urbanisation and climatic factors. Climate change, sedimentation, seepage, operational rules, contributing to the operation and management of the dams could have accelerated the drying up of the reservoirs and the prevailing water supply situation, which might continue to be the future possible challenges of water supply in the area.

Spatial Distribution Pattern and Terrain Analysis of Urban Flash Floods and Inundated Areas in Maiduguri Metropolis, Borno State, Northeast, Nigeria

Maiduguri metropolis Nigeria, lies on a relatively flat terrain of about 350 meters above sea level and is part of the undulating Borno Plain that slopes towards the Lake Chad. The rapid physical expansion of the metropolis and the annual recurrent flash flooding and inundation problems within the city continues to impact devastating socioeconomic effects on the livelihood of residents sometimes leading to loss of lives and property. It is important therefore to understand the spatial pattern of floods and terrain characteristics in Maiduguri for planning purposes. The paper examined the spatial pattern of urban flash floods and inundations, and the terrain characteristics in Maiduguri metropolis. Digital Terrain Model (DTM) generated from the Shuttle Raddar Topography Mission was used to provide the basis for the terrain analysis to generate hydrological parameters such as elevation, flow accumulation and direction, drainage network and slope angle as well as classified elevation images and terrain wetness index to map out potential flood risk areas. The DTM identified potential areas liable to flash flood and inundation. The 3D Digital Terrain Model (DTM) of the area showed where potential floods or traps were located in the metropolis. The findings further revealed that Maiduguri was generally characterized by low lying locations with slope angles of less than 5 degrees covering an area of 144.4 km2 out of 148 km2 making it extremely difficult to drain. The processed flow accumulation of the study area showed a high flow accumulation pixel value of 19,972 that drained into outlet, suggesting that a large proportion of the study area was getting flooded during a rainstorm. Even though the calculated drainage density of 0.73 for the study area indicated a very good drainage system, this was also undermined by the flat terrain and urbanization. The study recommends for improved land use planning;raising awareness of the residents, provision of more drainages and continued vulnerability mapping improved the functionality of bodies responsible for flood management among others for sustainable flood management in the study area.

Geological environment conflicts of Kunming Basin and its urban sustainable development

Kunming Basin locates middle of Yunnan altiplano and has a particularity in geography,topographic and geological environment.With the urban dilation quickly,add the reason of the unreasonable city layout,conflicts between environment and urban resources consumption become shrill increasingly.It is human being activities that lead to vulnerability and depravation of geological environment in local.Take a few examples on geological environment to expatiate relationship between urban construction and geological environment carrying capacity,and find a way how to make a better plan for urban sustainable development to achieve new balance between man and nature in local.

城乡居民医保整合与农村相对贫困治理的准自然实验研究

推进基本公共服务均等化、防范农村相对贫困是巩固拓展脱贫攻坚成果、促进城乡共同富裕的内在要求。论文基于2013年和2018年中国健康与养老追踪调查数据以及2013年和2019年中国家庭金融调查数据,运用双重差分倾向得分匹配模型,实证检验城乡居民医保整合对农村相对贫困脆弱性的影响。研究发现,城乡居民医保整合显著降低了农村相对贫困脆弱性。这种影响在低收入群体和受大病冲击群体中更加显著,但慢性病患者受到的影响并不显著,且城乡居民医保整合的减贫防贫效应随着脆弱性标准提高呈现下降趋势。机制检验表明,医疗费用支出、健康、劳动参与和家庭资产积累是重要的作用渠道。在此基础上,论文从动态认定相对贫困人口、促进低收入家庭应保尽保、提高农村医保实际保障水平和开展减贫绩效评估等方面提出推进农村相对贫困长效治理的政策建议。

基于VSD模型的陕南城市群水资源脆弱性评价及影响因子研究

[目的]构建基于社会-经济-生态耦合作用下的陕南城市群水资源脆弱性模型,阐明水资源脆弱性状态,厘定影响因子,助力秦岭地区人水和谐。[方法]基于暴露度-敏感性-适应性(Vulnerability Scoping Diagram,VSD)对陕南城市群水资源脆弱性进行了评价,结合多元统计法,进一步识别了社会-经济-生态耦合作用下水资源脆弱性的影响因子。[结果]2011—2020年,陕南整体水资源脆弱性的变化趋势与商洛市最相似,除2011年极度脆弱外,基本保持在轻度脆弱状态,而汉中市和安康市的水资源脆弱性等级较高,水安全保障程度相对较低;陕南城市群水资源脆弱性的主控因子有生态环境用水量、人均水资源量、年降水量;优化生态环境用水量分配,加强对年降水量与人均水资源量监测,将成为陕南城市群降低水资源脆弱性新的工作重心。[结论]陕南城市群水资源系统安全性的提升与当地注重水生态文明建设以及与社会-经济协调发展有关。此外,构建的VSD模型适用于陕南城市群水资源脆弱性评价,可为缓解人-城-水矛盾提供理论指导。

黄河“几”字弯都市圈资源环境承载力与经济发展耦合协调研究

在生态文明建设理念下,如何实现生态脆弱区资源环境与经济的协调发展,已成为我国亟待解决的问题之一。以典型生态脆弱区黄河“几”字弯都市圈21个地级市为例,基于2005年、2010年、2015年、2020年的资源环境与经济发展数据,运用熵权TOPSIS法分析资源环境承载力状况,并引入耦合协调度模型揭示资源环境承载力与经济发展水平耦合协调关系及其时空演变特征,结果表明:黄河“几”字弯都市圈资源环境承载力呈波动上升趋势,区域差异显著;资源环境承载力与经济发展水平的耦合协调度整体逐渐趋向于更高程度的耦合;通过莫兰指数分析发现,黄河“几”字弯都市圈资源环境承载力与经济发展水平耦合协调度为显著空间正相关。

生态脆弱性与城镇化水平时空耦合及其交互影响因素——以湖南省为例

协调生态建设与城镇化是实现区域可持续发展的保证,对科学引导城镇化并实现高质量发展具有重大意义。为探究我国中部地区生态环境脆弱程度与城镇化水平整体进程之间的关系,以湖南省为例,各县区为评价单元,基于生态敏感性-生态恢复力-生态压力度模型构建生态脆弱性评价指标体系,通过人口-经济-社会-空间模型构建城镇化水平评价指标体系,通过耦合协调度模型多维度测算湖南省2000—2020年生态脆弱性和城镇化水平的空间耦合关系,并运用双变量空间自相关、时空地理加权回归模型探究其交互影响效应。结果表明:(1)研究期间,湖南省生态脆弱程度呈先加重后减轻的趋势,以长株潭为核心重度脆弱区,向南北方向扩散,形成南北地区脆弱程度高、中西部生态脆弱程度低的格局;(2)城镇化水平差异较大,总体呈现上升的趋势,高水平城镇化区域从2000年以各地级市行政中心向外发散的散点式布局,到2020形成以长株潭为核心高值区,东部整体较高,西部偏低的空间分布格局;(3)湖南省严重失调区县明显减少,基本协调区县明显增加的趋势,且城镇化水平是制约湖南省生态环境与城镇化均衡高质量发展的主要因素。(4)交互作用结果表明,城镇化发展导致地区生态脆弱程度加深,而地区生态状况又反向制约城镇化水平可持续、高质量发展。研究表明,湖南省需着力推进生态环境建设和城镇化水平的健康发展,缓解城镇化发展和生态环境的矛盾,以期实现区域城镇化与生态协同发展。

基于精细化空间格局的城市承灾体脆弱性评估

针对目前流域内部跨行政区单元空间精细化模拟并用于评估城市洪涝灾害工作的空白,本文着重聚焦精细化经济指标空间分布并将多源数据融合,构建了基于精细化空间格局的城市承灾体脆弱性评估体系,量化了深圳河流域脆弱性等级。研究结果表明:单一数据不足以准确模拟流域GDP密度,结合多源数据是进行GDP空间精细化更加有效的办法;深圳河流域GDP密度与第二、三产业空间化结果显示出高度一致性,产值密度最高达617214万元/km^(2);流域两岸脆弱性等级存在显著差异和区域特征,深圳侧脆弱性明显高于香港侧,高脆弱性地区约占流域面积的8.8%。研究结果有助于识别灾害危险性大小和损失程度,提高城市洪涝灾害评估的精确性。

城市暴雨洪涝灾害脆弱性评价

基于脆弱性概念阐述暴雨洪涝灾害下的城市脆弱性内涵,从暴露度、敏感性和适应能力3个方面构建了包含11个指标的城市暴雨洪涝灾害脆弱性综合评价指标体系和评价模型,并确定脆弱性等级划分标准。以南京市秦淮区为例,针对100年一遇设计暴雨情景,基于MIKE一二维耦合模型,定量分析指标值,采用构建的评价模型计算了城市暴雨洪涝灾害脆弱性指数,对极端暴雨情景下研究区的脆弱性进行了评价,绘制了研究区脆弱性空间分布图,分析了脆弱性分布特点与成因。结果表明:MIKE一二维耦合模型可用于暴露度指标中最大淹没水深和时段末淹没水深的获取;河流沿岸且地势较为平坦的区域,交通路网中的低洼区域、立交桥下易形成积水的区域,人口稠密、GDP产值高、暴露程度较高的居民住宅区与企业中心等区域脆弱性较高。