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1.
Geospatial data and tools are key in locating lost or missing persons in as short a time as possible. In this study, we used a geographic information system (GIS) to analyze four years of search and rescue (SAR) mission data from Colorado to determine the appropriate use of GIS for volunteer-based SAR organizations with limited resources and GIS expertise. GIS can provide more sophisticated analyses of geospatial data than simple mapping technologies, but our findings indicated that complex spatial analysis might not be required on all missions, because the majority of missions were completed within six to ten hours. Instead, new technologies such as tablets with mapping software and online GIS systems that provide quick and easy access to up-to-date geospatial data such as imagery offer capabilities that could improve mission planning. Here we provide a framework in which SAR missions can apply geospatial technologies to aid with missions, identify critical “hotspots,” and enhance postanalysis and training. The work here is highly applicable for nonprofit SAR groups when deciding on what GIS technologies to consider for their areas. 相似文献
2.
为保障船舶海上航行安全,结合GIS与模糊层次分析法,从海上搜救的自然环境和人文搜救力量2个方面选取9个因子建立海上搜救困难性评价模型,对南海海上搜救困难性进行评价。结果表明：1）自然环境影响下,南海海域搜救困难性具有“V”字形分布的特点,由东北向西南难度等级逐渐降低。2）在人文搜救力量影响下,南海海域的搜救困难性整体呈“东北－西南条带式”,难度最大的区域主要位于南海东北―西南的连线上,呈不规则环状向连线两侧递减。3）综合两方面因素,南海部分岛屿周围搜救难度偏高,主要受台风等恶劣天气及远离搜救基地的影响,而远海海域搜救难度在整体上为“东北－西南递减式”空间分布格局,最高和较高的区域由研究区东北延伸至西南,然后向西北、东南两侧递减。总体而言,南海研究区中近21.1%的海域搜救难度≥7级,仍需加强对搜救力量的部署与建设。 相似文献
3.
Dieudonné Tsatcha Éric Saux Christophe Claramunt 《International journal of geographical information science》2014,28(7):1355-1377
Route planning is an important problem for many real-time applications in open and complex environments. The maritime domain is a relevant example of such environments where dynamic phenomena and navigation constraints generate difficult route finding problems. This paper develops a spatial data structure that supports the search for an optimal route between two locations while minimizing a cost function. Although various search algorithms have been proposed so far (e.g. breadth-first search, bidirectional breadth-first search, Dijkstra’s algorithm, A*, etc.), this approach provides a bidirectional dynamic routing algorithm which is based on hexagonal meshes and an iterative deepening A* (IDA*) algorithm, and a front to front strategy using a dynamic graph that facilitates data accessibility. The whole approach is applied to the context of maritime navigation, taking into account navigation hazards and restricted areas. The algorithm developed searches for optimal routes while minimizing distance and computational time. 相似文献
4.
STEPHEN J. CARVER 《International journal of geographical information science》2013,27(3):321-339
Abstract Geographical information systems (GIS) provide the decision-maker with a powerful set of tools for the manipulation and analysis of spatial information. The functionality of GIS is, however, limited to certain deterministic analyses in key application areas such as spatial search. The integration of multi-criteria evaluation (MCE) techniques with GIS is forwarded as providing the user with the means to evaluate various alternatives on the basis of multiple and conflicting criteria and objectives. An example application based on the search for suitable sites for the disposal of radioactive waste in the UK using the Arc/Info GIS is included. The potential use of a combined GIS-MCE approach in the development of spatial decision support systems is considered. 相似文献
5.
Computer-assisted navigation systems provide navigation information to automobile drivers and are now available. They are capable of storing, processing and displaying information about street networks. The display typically mimics a printed street map. The underlying capabilities of these systems present unique opportunities for geographers to study spatial cognition, wayfinding, spatial search, the impact of spatial information on trip behavior, and market responses to potentially different travel patterns. Such systems are reviewed and key areas for future research are identified. 相似文献
6.
基于潜能模型的医疗设施空间可达性评价方法 总被引：15，自引：4，他引：11
空间可达性是评价医疗设施布局合理与否的重要指标,传统的医疗设施空间可达性评价,或者从医疗服务供需状况着手,或者从供需双方之间距离因素着手,均无法全面评价居民实际所能获取的医疗资源。本文采用基于潜能模型的评价方法对江苏省如东县医疗设施空间可达性进行分析研究,该方法综合考虑了医疗设施服务能力、居民点人口数量、医疗设施与居民点之间的出行阻抗。研究表明,通过选取合适的出行摩擦系数,该方法能够较为全面准确地测度较小研究单元的医疗设施空间可达性,辅以GIS技术,可以很直观地揭示研究区域内医疗设施空间可达性差异,结合公共卫生管理部门制定的医疗资源配置标准,还可较为准确判定缺医地区,为政府相关部门规划决策提供依据。 相似文献
7.
空间信息技术支持下的沿海风能资源评价 总被引：7，自引：0，他引：7
沿海地区是我国重要的风能资源区,由于近地面风场具有很强的时空变异性,给风能资源定量评价带来了很大困难.空间信息技术的发展为我们提供了新的视角和手段,近年来,利用星载合成孔径雷达(SAR)进行沿海风场信息遥感反演已从试验逐步走向成熟,它以布拉格原理为依据,建立合成孔径雷达后向散射系数与海面风场之间的关系,反演风速、风向等关键参数,并进而对研究区风能资源进行准确的定量评价.本文回顾了本领域国内外研究进展,重点阐述了风场要素反演的基本方法和校验手段,探讨了目前存在的一些问题和改进方法,并对本方法在我国的应用前景作了展望. 相似文献
8.
世界遗产预备项目“丝绸之路-海路-中国段”研究 总被引：2，自引：1，他引：1
中国海上丝绸之路申遗于2016年正式启动,迄今尚无有关中国海上丝绸之路申遗专题的综合研究成果。首先建议申遗项目的中英文名称：丝绸之路-海路-中国段（Silk Road-Maritime Route in China）,然后探讨“丝绸之路”申遗的国际背景（除1项“丝绸之路：长安-天山廊道路网”系列跨国世界遗产外,另有8国递交9项“丝绸之路”预备项目）与“丝绸之路-海路-中国”项目的申报意义（主动性、创新性、唯一性、均衡性、政治性、世界性）。并就申报项目的遗产内容提出具体建议：遗产地从31处扩展至141处,遗产类型在文物遗产的基础上增加了聚落遗产（历史文化名镇、名村、街区）。最后提出在UNESCO世界遗产委员会建立“丝绸之路-海路”申遗专项基金。 相似文献
9.
THANASIS HADZILACOS NECTARIA TRYFONA† 《International journal of geographical information science》2013,27(2):179-203
Abstract. A formal, yet practical, GeoRelational Data Model (GRDM) is presented for the logical database design phase of the development of spatial information systems. Geographic applications are viewed in the context of information systems development. The generic needs of modelling spatial data are analyzed; it is concluded that they are not served satisfactorily by existing data models, so specifications of modelling tools for spatial application design are given. GRDM provides a set of representational constructs (relations and layers for the logical schema; virtual layers, object classes and spatial constraints for the user views) on top of well-established models. It constitutes part of a full, easily automated application design methodology. Extensive examples demonstrate the relevance, and ease-of-use of the platform-independent GRDM. 相似文献
10.
中国民用运输机场的可达性溢出效应研究 总被引：3，自引：0，他引：3
交通基础设施投资的“利己利人”甚至“损己利人”现象使得空间溢出效应一直是研究的热点。我国民用运输机场经过属地化改革之后,地方政府在机场投资和运营中的作用越来越突出,机场的空间溢出效应逐步受到地方政府和研究者的关注。针对机场所在地辖区和机场服务范围存在空间错位,本文定义某辖区的机场可达性溢出效应为该辖区范围内的机场对周边地区到机场可达性的改善程度,并基于潜力模型和网络分析方法设计了机场可达性溢出效应的计算方法;进而以我国民用运输机场为例,在机场属地化背景下确定了省级和市级两种研究尺度,采用县级数据分别定量计算了我国民用运输机场的可达性溢出效应。结果发现,我国省级尺度的机场可达性溢出较小;市级尺度的可达性溢出差异较大,部分城市机场可达性溢出显著,但空间分布较为复杂。本文还进一步讨论了计算结果对我国机场投资和运营成本空间分担制度设计的启示。 相似文献
11.
面向地震应急准备的居民地遥感提取及量化分析 总被引：2，自引：1，他引：1
运用灰度共生矩阵、数学形态学等方法提取新疆新源地区高分一号2 m分辨率影像居民地信息,运用目视解译、影像叠加分析、缓冲区分析等方法,进行居民地量化分级,为地震应急准备提供数据支持。结果表明：研究区在地震烈度为Ⅷ度及以下区域,埋压主要集中在单层结构为主的建筑区;当地震烈度高于Ⅷ度且造成多层建筑大面积倒塌时,县城等人口密集区为首要救援区;在地震应急准备时,应对交通条件三等区和交通条件四等区重点关注,增加应急物资储备点,对山区居民地,应考虑道路毁坏情况,转换救援方式,做好应急预案。 相似文献
12.
G. B.M. Heuvelink Z. Jiang S. De Bruin C. J.W. Twenhöfel 《International journal of geographical information science》2013,27(3):365-382
In case of a nuclear accident, decision makers rely on high-resolution and accurate information about the spatial distribution of radioactive contamination surrounding the accident site. However, the static nuclear monitoring networks of many European countries are generally too coarse to provide the desired level of spatial accuracy. In the Netherlands, authorities are considering a strategy in which measurement density is increased during an emergency using complementary mobile measuring devices. This raises the question, where should these mobile devices be placed? This article proposes a geostatistical methodology to optimize the allocation of mobile measurement devices, such that the expected weighted sum of false-positive and false-negative areas (i.e. false classification into safe and unsafe zones) is minimized. Radioactivity concentration is modelled as the sum of a deterministic trend and a zero-mean spatially correlated stochastic residual. The trend is defined as the outcome of a physical atmospheric dispersion model, NPK-PUFF. The residual is characterized by a semivariogram of differences between the outputs of various NPK-PUFF model runs, designed to reflect the effect of uncertainty in NPK-PUFF meteorological inputs (e.g. wind speed, wind direction). Spatial simulated annealing is used to obtain the optimal monitoring design, in which accessibility of sampling sites (e.g. distance to roads) is also considered. Although the methodology is computationally demanding, results are promising and the computational load may be considerably reduced to compute optimal mobile monitoring designs in nearly real time. 相似文献
13.
This study attempts to identify areas with a high level of discrepancy in the probability for an individual to exceed the threshold of walking time for grocery shopping. It is based on an assumption that a higher discrepancy is associated with more relative disadvantages for socially excluded people, the elderly, with no car and unemployed. A geographically weighted logistic model that incorporates individual constraints and spatial accessibility is developed to yield a probability, capturing the spatial variation of relations of factors. In the city of Tokyo, the north-eastern area shows a significant discrepancy for the socially excluded group. The distribution of high level of discrepancy differs compared to that of the area with low accessibility. This study's methodology and results provide convincing evidence that in determining food desert areas, relative accessibility estimated with personal attributes should be taken into account. 相似文献
14.
儿童服务设施是建设儿童友好性城市的重要内容。基于北京城区社区人口数据及儿童服务设施数据,通过两步移动搜寻法,以社区为单元分析儿童服务设施可达性的空间格局及分布模式。结果显示,不同类别儿童服务设施空间可达性服务水平差异较大,在1000米阈值范围内小学的空间可达性水平优于幼儿园,3000米阈值范围内儿童诊所的空间可达性优于公园。受儿童人口和儿童服务设施分布的影响,小学、幼儿园、儿科门诊的可达性均呈现“中心高、边缘低”的分布格局,空间分布不均衡;公园分布则相对分散,其可达性呈现边缘区域优于中心区域分布特征。北京城区儿童服务设施可达性情况可分为五种类型区,类型区之间以同心圆的结构进行组合,局部体现出扇形的特征。据此提出针对不同区域儿童服务设施的改善策略。 相似文献
15.
基于“海上丝绸之路”通道安全的海外港口战略布局研究 总被引：2，自引：0，他引：2
本文研究了“海上丝绸之路”通道网络安全的海外港口布局，对沿线集装箱港口及航线挂靠情况进行统计分析，探讨了“海上丝绸之路”主要通道通航受阻时网络连通性的变化。根据地缘特点，对“海上丝绸之路”所覆盖海域的通道安全进行了风险分析；为加强“海上丝绸之路”运输网络的风险控制，保障其互联互通，结合地缘风险探讨了近年来我国对“海上丝绸之路”沿线港口投资的分布状况。研究表明，为加强“海上丝绸之路”的畅通性，应在保障本国港口和周边海域海上通行安全的同时，积极参与全球不稳定因素的治理，进一步加强“海上丝绸之路”各个国家间的友好往来；重点加强在莫桑比克海峡和英吉利海峡周围的港口布点；在主动布局各海上通道投资港口的同时，还应不断加强海上军事力量建设，建立海外军事基地，提升海军的远洋能力，增加我国在重要海上通道周边海域的军事存在；积极推动沿线国家的政治互信，促进区域的和平发展。本文成果对于科学规划我国在“海上丝绸之路”的海外港口布局具有重要借鉴价值。 相似文献
16.
This study examines spatial accessibility of pharmacies in Baton Rouge, Louisiana. Two popular geographic information systems (GIS)—based methods are compared: the proximity method uses the distance (travel time) from the nearest pharmacy, and the two‐step floating catchment area (2SFCA) method considers the match ratio between providers and population as well as the complex spatial interaction between them. The study indicates that disproportionally higher percentages of African‐Americans are in areas with shorter travel time to the nearest pharmacies than whites, but suffer from poorer accessibility measured by the 2SFCA method—that is, fewer pharmacies per 10,000 residents. Seniors, particularly those of seventy‐five years or older, tend to be disproportionally concentrated in areas that not only are closer to pharmacies, but also have more pharmacies per 10,000 residents. The two methods used in the study capture different elements in spatial accessibility: one being physically close to a facility and another adding the crowdedness in service. Both properties can be valuable for residents. The two may not always coincide with each other in spatial variability, as it is the case for racial disparity in our study area. However, when they do, as in the case for seniors, it may imply a true (dis)advantage for a demographic group in terms of both properties of spatial accessibility. 相似文献
17.
Inshore artisanal fishing in Malta is under intense spatial competition as the coastal zone is fragmented by multiple uses and designations including maritime transport, infrastructure, industrial fisheries, aquaculture, tourism and recreation. This research, adopting a grounded visualization methodology, explains how the artisanal fishing sector has undergone and been affected by ‘spatial squeezing’. Our results show that artisanal fishermen have been forced to give up fishing grounds or co-exist with other uses to the point where the ability to fish is becoming increasingly challenging. These difficulties might escalate with the advent of the marine protected areas (MPAs) which encompass nearly half of the inshore fishing zones. Since there does not seem to be effective MPA consultation mechanisms that elicit the real social, cultural and economic value of artisanal fishing grounds, fishermen feel threatened, alienated and disempowered. This study urges for a more holistic approach to spatial marine planning and accentuates the need of realizing the dependency of the artisanal sector on the inshore zones in the implementation of conservation measures, such that the prolonged existence of the coastal fishing communities is not jeopardized. 相似文献
18.
《地理学报(英文版)》2010,(5)
Based on the case study of peripheral urban areas in Beijing,this paper aims to identify the factors which will influence the spatial distribution of peri-urban recreation areas,by analyzing the collected data from questionnaires,online survey,documentation and field investigations(2007).In order to achieve sound information,relevant data from different management departments,owners and land-use types involved in the case study area are collected.A sampling database for peri-urban recreation areas in Beijing is established,and GIS spatial analyses as well as statistic analyses are applied.The result indicates that spatial distribution of recreation areas is majorly influenced by four factors,e.g.tourism attractions and environmental conditions,policy and spatial governance,consumption demand and preference,land price and availability.Tourism attractions and environmental conditions are dominant factors for public recreation areas.Commercial recreation areas are highly related with accessibility.Agricultural recreation areas are usually attached to special farmlands near large-scaled scenic areas.Meanwhile,recreational business clusters have appeared in suburbs influenced by mass recreation market growth.Controlled by the land price,commercial recreation areas are differentiated on their scales and developing intensity.Policy and spatial governance have made arrangements of recreation areas more balancing and more human-oriented.A peri-urban recreation area model is therefore established on the basis of this analysis,which can guide urban planning and designing,land-use planning and recreation resource development. 相似文献
19.
Highly technological in vitro fertilization (IVF) treatment is available at relatively few medical centers in rural United States. This research derives a spatial accessibility surface for IVF centers in a rural Midwestern state through the application of computational methods that consider spatial and non-spatial parameters to discover potentially underserved areas in the state. These methods include a modified gravity model and techniques from spatial interaction modeling. The approach develops an enhanced accessibility index that incorporates three key sociodemographic variables describing patients seeking infertility healthcare in Iowa that have been identified based on a survey of IVF care practitioners in the state. Self-organizing map techniques are used to reveal cluster locations based on the degree of match between census sociodemographic data and the expert-identified variables. The spatial accessibility surface is combined with the sociodemographic clusters to define an enhanced measure of spatial accessibility. The results suggest that while the state's IVF centers are located in tracts characterized by high spatial accessibility, at least 19% of patients travel from census tracts classed as moderate to low accessibility. This result reveals some opportunities for service improvements for these locations. Interestingly, for tracts that are characterized as having a lower patient sociodemographic match, high spatial accessibility does not appear to be a factor that improves the likelihood of patient care, at least for the variables investigated as part of this research. 相似文献
20.
论我国沿海地区的海陆经济一体化 总被引：14，自引：0，他引：14
在给定了海洋产业概念的基础上,重点论述了海域自然基础的特殊性,海洋产业结构与陆域产业结构的差异,并从技术和陆域产业向海洋延伸的可能性等方面分析了海洋产业和陆域产业间形成差异的原因;在海岸带地区由海洋生态系统和陆域生态系统所形成的复合生态系统是海陆产业联系的自然基础,而海洋产业对陆域的技术和空间上的依赖则决定了海陆经济一体化的必然性;最后,作者从发展临海产业,海陆统一规划和协调海陆生态系统等三方面论 相似文献