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1.
改善通风的城市形态因素可以分为建筑和道路2个方面。建筑形态的通风评价主要采取综合迎风面积密度方法,将城市建筑环境转化为具有数值属性的栅格,从而提取城市建成区的通风廊道,但是该方法忽略了城市重要的通风路径——城市街道。以街道的朝向为主要评价对象,挖掘线状要素城市道路的通风廊道,作为建筑形态通风廊道划分方法的补充。根据通风潜力随夹角的变化规律,利用地理信息系统(GIS)的空间分析技术进行街道的通风潜力评价,在综合迎风面积密度密集的区域,存在通风潜力较高的城市街道  相似文献   
2.
The increasing size of chemical plants and rapid growth in residential areas has led to many incompatible land-use scenarios in the last 100 years. In this context, the authors assume that assessment and planning have their significant role in preventing the juxtaposition of hazards and population, and that, in this field, there is a broad recognition of the need for legislative and policy consistency across the European Union. The paper presents a comparative case study in which the Romanian land-use planning (LUP) criteria and the risk-based quantitative approach for a chemical plant are applied. Accident scenarios involving chlorine and propylene arecomprehensively analyzed using consequence and risk modelling software and GIS technique for the territorial compatibility assessment. The objective of the paper is threefold. Firstly, it presents an overview about current risk analysis methods; secondly, the authors advance an understanding of risk assessment practices used in several countries for the prevention and control of major industrial accidents involving dangerous substances and, also, for LUP. Thirdly, a method targeting an improved risk assessment framework for LUP, encompassing Romania’s determinants is outlined. The results obtained using the two different approaches indicate significant differences regarding the possibly affected areas and territorial compatibility. Furthermore, based on the findings, the paper ends with a set of recommendations that can be transformed into the foundation for future enactments of new safety standards that cover risk assessment for LUP. Consequently, the present study aims to become a frame of reference for decision-makers towards more sustainable and updated risk assessment practices in the field of industrial activities.  相似文献   
3.
现代化农区耕地利用形态转型研究   总被引:3,自引:0,他引:3  
[目的]耕地利用转型是农业发展转型和土地利用转型的重要组成部分。探讨现代化农区耕地利用形态转型的一般特征,可以为区域耕地资源优化配置提供科学依据。[方法]基于GIS平台,结合耕地利用动态度、区域差异指数、耕地景观格局变化表征模型,分析黑龙江省垦区建三江管理局1976~2014年耕地利用形态变化规律。[结果](1)建三江垦区耕地利用可以划分为4种典型形态:耕地散布态、耕地密布态、耕地连布态和耕地满布态,耕地形态转型经历了旱地拓张期(1976~1986年)、水田萌发期(1986~1996年)、水田拓张期(1996~2006年)和旱—水转换期(2006~2014年);(2)旱地拓张期,垦殖率由18.55%猛增至45.96%,旱地占土地总面积比重由18.55%升至44.34%,旱地景观格局集聚度不断提升,水田"零星"镶嵌于研究区内;(3)水田萌发期耕地总量稳中有升,水田面积小幅增加,占耕地面积比重由3.53%提升至6.63%,水田景观破碎度较高;(4)水田拓张期垦殖率基本稳定,新增耕地以水田为主,主要来源于未利用地(沼泽地)、草地、林地的垦殖以及旱地转化,水田种植优势明显增强,景观集聚度升高;(5)旱—水转换期,水田比重由29.48%上升至80.90%,主要表现为耕地内部旱地—水田的转变。水田最大斑块所占景观面积比例骤然上升,水田逐渐占据绝对优势地位,逐渐由"破碎化"转向"聚集化"。(6)气候变暖、地貌适宜、经济效益是该区域耕地利用转型的重要原因,但地形地貌、土壤等自然条件以及发展水平、交通区位等社会经济条件的差异,使得耕地利用转型具有区域差异性。[结论]黑龙江省垦区建三江分局在全球气候变暖和国家粮食安全战略背景下,其耕地利用经历了面积逐渐扩展、结构不断调整的形态转型,其本质是农业生产投入规模和强度的提升。耕地利用形态转型规律可以为区域耕地利用调控提供依据。  相似文献   
4.
ABSTRACT

Tourism related stress has recently been revealed as an issue for tourism host community residents. Prior studies have relied on directly asking residents if tourism caused them stress, resulting in possible participant priming. This study utilized the ArcGIS Survey123 app to collect data on resident stress from a community with high levels of tourism visitation and a community with low levels of tourism visitation. During the study, researchers never mentioned tourism. Half of study participants in the community with high tourism visitation discussed tourism directly as a stressor, accounting for almost 5% of all stressful experiences, while no participants in the community with low tourism visitation mentioned tourism as a stressor. Geospatial data revealed that tourism related stressors occurred outside of the ‘tourism zone’ in the community with high tourism visitation, and tourism related stressors mirrored perceived tourism impacts measured in a post experiment survey of study participants.  相似文献   
5.
在当今社会经济的不断发展中,人们的环保意识也实现了不断提升,而伴随着科学技术的发展,各种先进技术也开始逐渐应用到了环境保护工作中。其中,GIS技术就是一项典型的环境影响评价技术。通过该技术的应用,可以让环境资源、生态资源、土地资源、林业资源以及农业资源等领域得到良好的影响评价,以此来保障资源与环境之间的可持续发展。基于此,论文对该技术在环境影响评价中的具体应用策略进行分析,希望可以为GIS技术在环境影响评价中的合理应用以及环境影响评价效果的提升提供足够动力。  相似文献   
6.
河南省传统村落空间分布特征及影响因素研究   总被引:1,自引:0,他引:1  
[目的]分析河南省传统村落的空间分布特征及其影响因素,以期为中原地区传统村落的建设发展提供指导。[方法]文章通过谷歌地理信息系统及Arc GIS10. 2软件对河南省124个国家级传统村落的空间分布类型、分布格局、分布均衡型及影响因素进行分析,采用最邻近距离法、核密度估计法及地理集中程度等方法揭示其空间分布特征及其形成的影响因素。[结果]最邻近距离法分析R=0. 628,小于1,分布类型为凝聚型。核密度分析中,整体空间分布呈现3个核心区域,平顶山东北区域,豫西北沿省边界呈带状分布及豫南信阳南部,空间分布受地理、经济和文化等因素影响。[结论]河南省传统村落的空间分布属凝聚型不均衡分布。从地级市层面上分析,主要集中在平顶山东部、信阳南部和三门峡地区;从分区层面上,以豫中较多,豫北、豫西和豫南其次,豫东基本空白。形成原因与地理高程、社会经济和历史事件有关。交通不便、经济相对发达或相对落后、历史事件少发的区域,传统村落保存较为完整。  相似文献   
7.
In many Brazilian cities, the most common procedure for planning cycling networks is using aggregated population data in census tracts, which may not take into account the true origin and destination of trips. It may also not identify potential users of a particular mode of transport. This is particularly important considering that implementing cycling infrastructures should be based on the assumption that they are able to meet the users' needs. Therefore, the aim of this study is to develop and adopt an objective method to design and compare cycling networks based on data-mining of disaggregated origin-destination data, GIS resources, and multicriteria analysis techniques. The method follows three steps: 1) identifying potential users based on real user profiles, 2) designing proposed cycling networks and 3) a comparison between the networks proposed in this study and those developed by the municipality selected as a case study, considering real and potential users, as well as cost and benefit criteria. As a positive outcome, using disaggregated data allows for a reasonable estimate of the number of people served by the networks, a detailed analysis of their proximity to the infrastructure, as well as identifying potential users. Comparing cycling networks considering cost and benefit criteria shows that the chosen criteria were effective. It was also determined that the cycling network of the studied city poorly serves bicycle transport users, if compared to the proposed networks. These findings indicate that appropriate methods for planning cycling networks are still needed.  相似文献   
8.
Fire stations play a central role in protection and response activities as part of emergency management services in cases of fire incidences. With the rising urban populations and city expansions, the demand for more fire services resultantly increases. It then becomes critical to effectively plan the location of emergency facilities to adequately service the population and ensure the protection of lives and infrastructure. This study, therefore proposes the use of the fuzzy extension of the Multi-Criteria Decision-Making (MCDM) method of Analytical Hierarchical Process (AHP), hence called fuzzy AHP, integrated with Geographic Information Systems (GIS) approach to optimally site new fire stations for the case of Istanbul region. This proposed fuzzy approach simulates the subjective expert judgements for the preferences of the six criteria assessed for fire station suitability mapping and thereby accounted for the uncertainty of crisp comparison values via triangular fuzzy numbers (TFNs). The criteria weights evaluated from this procedure were used in a weighted overlay analysis of the reclassified criteria map layers in ArcGIS to generate a fire station suitability map. These resultant fuzzy AHP criteria weights were validated using another MCDM technique, called Best-Worst Method (BWM) and found to be comparable and consistent. The criteria that had the strongest influence on the selection of sites for fire stations were identified to be: the density of hazardous material facilities (DHM), a high population density (HPD) and proximity to main roads (PMR) with associated weights of 33.3%, 24.4% and 15.2%, respectively. Based on a thorough assessment within the areas represented by class values ranging from 3 to 5 on the suitability map, a total of 34 new fire station sites were selected complementing the existing 121 fire stations. Further, a prioritization analysis from low, medium to high, was performed to plan the phases for the construction of new fire stations in view of competing budgetary needs and resource constraints. The methodology to achieve this was proposed and modelled for enhancing the decision-making process in urban fire station site selection studies.  相似文献   
9.
随着城市人口的增加和人们健康意识的增强,近年 来城市公园的使用率呈现迅速上升趋势。手机等智能电子设备 的高速发展,使人们可以在户外运动中监测自身活动轨迹、距 离和能量消耗等。以北京奥林匹克森林公园为例,通过手机 信令、微博、百度POI等大数据与GIS技术结合,构建依托大 数据的GIS耦合模型,从游人的行为需求出发对公园的慢跑游 线、景点热度、游人空间分布等进行使用后量化评价,并针对 问题提出北京奥林匹克森林公园的景观优化策略。结果显示大 数据与GIS的结合可以为公园的景观优化提供客观且理性的整 改依据,从而更科学地指导城市公园的景观提升。  相似文献   
10.
Understanding how spatial attributes of cities and neighborhoods induce cycling is relevant for urban planning and policy making. In this work, ordered logit and latent class models are specified and estimated to analyze how the built environment affects bicycle-commuting frequency. Data come from a survey to 1,487 people in the city of Santiago, Chile, including sociodemographic information, travel behavior patterns and place of residence and work. Using geographic information systems tools, the built environment was characterized with variables calculated for a 500-m-radius buffer around the residential and work locations of each individual. Two models are estimated, first an ordered logit model confirms that built environment variables effect on cycling is similar to what has been reported in the literature, with some new findings such as an increase in cycling when public transport accessibility is low and the role of built environment attributes at the destination. Second, a latent class ordered logit is used to identify two classes of neighborhood in term of their cycling patterns, as a function of their density, presence of cycling infrastructure and distance to the main activity center of the city. This result allows to map the class membership probabilities, potentially helping to identify neighborhoods that encourage cycling and providing relevant information for policy making and infrastructure decisions.  相似文献   
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