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1.
应用地理信息系统探测消化道癌症死亡率空间聚集性   总被引:6,自引:0,他引:6  
根据研究区分村4种消化道癌症死亡监测数据和人口数据,描述癌症死亡率的空间分布规律,探测病例在空间上存在的聚集性热点,为进一步开展环境和人群监测提供参考依据。本研究采用基本的图层Voronoi处理技术以及全局空间自相关和空间热点探测的方法,通过绘制空间自相关系数图,描述不同空间尺度与消化道癌症死亡率自相关系数之间的关系。结合空间探测技术和癌症死亡率分布特点,确定空间探测的合理参数,应用地理信息系统,对消化道癌症在研究区的空间聚集热点进行探测。结果发现,研究区在4300m尺度存在有意义的显著空间正自相关,探测到3个消化道癌症高值聚集区,共58个村,每个聚集区平均人口在3万左右。3个聚集区癌症粗死亡率明显高于非聚集区和该县平均粗死亡率。空间热点的探测与分析,引入空间权重矩阵的概念,弥补传统统计学缺乏空间信息和空间关联的缺陷,为引起消化道癌症高发的危险因素探寻提供线索,是传统统计学的必要补充。  相似文献   

2.
Geoscientific Information Systems (GIS) provide tools to quantitatively analyze and integrate spatially referenced information from geological, geophysical, and geochemical surveys for decision-making processes. Excellent coverage of well-documented, precise and good quality data enables testing of variable exploration models in an efficient and cost effective way with GIS tools. Digital geoscientific data from the Geological Survey of Finland (GTK) are being used widely as spatial evidence in exploration targeting, that is ranking areas based on their exploration importance. In the last few years, spatial analysis techniques including weights-of-evidence, logistic regression, and fuzzy logic, have been increasingly used in GTK’s mineral exploration and geological mapping projects. Special emphasis has been put into the exploration for gold because of the excellent data coverage within the prospective volcanic belts and because of the increased activity in gold exploration in Finland during recent years. In this paper, we describe some successful case histories of using the weights-of-evidence method for the Au-potential mapping. These projects have shown that, by using spatial modeling techniques, exploration targets can be generated by quantitatively analyzing extensive amounts of data from various sources and to rank these target areas based on their exploration potential.  相似文献   

3.
Knowledge representation structure and reasoning processes are very important issues in the knowledge-based approach of integrating multiple spatial data sets for resource exploration. An object-oriented knowledge representation structure and corresponding reasoning processes are formulated and tested in this research on the knowledge-based approach of integrating spatial exploration data. The map-based prototype expert system developed in this study has self-contained knowledge representation structure and inference mechanisms. It is important to distinguish between lack of information and information providing negative evidence for a map-based system because the spatial distribution of data sets are uneven in most cases. Error and uncertainty estimation is also an important component of any production expert system. The uncertainty propagation mechanisms developed here work well for this type of integrated exploration problem. Evidential bellef function theory provides a natural theoretical basis for representing and integrating spatially uneven geophysical and geological information. The prototype system is tested using real mineral exploration data sets from the Snow Lake area, northern Manitoba, Canada. The test results outline the favorable exploration areas successfully and show the effectiveness of the knowledge representation structure and inference mechanisms for the knowledge-based approach.  相似文献   

4.
This article reports on the results from a spatiotemporal analysis of disaggregate fire incident data. The innovative analysis presented here focuses on the exploration of spatial and temporal patterns for four principal fire incident categories: property, vehicle, secondary fires, and malicious false alarms. This research extends previous work on spatial exploration of spatiotemporal patterns by demonstrating the benefits of comaps and kernel density estimation in examining temporal and spatiotemporal dynamics in calls for services. Results indicate that fire incidents are not static in either time or space and that spatiotemporal variation is related to incident type. The application of these techniques has the potential to inform policy decisions both from a reactive, resource‐allocation perspective and from a more proactive perspective, such as through spatial targeting of preventive measures.  相似文献   

5.
全球气候变化及快速城市化增加了极端天气事件的发生频率,高温热浪作为其中的典型效应,增加了与热相关的健康风险,越来越受到气象学、医学与地理学学者的关注。论文系统梳理了高温热浪的定义,从地理学视角,以空间评估作为切入点,总结分析了高温热浪脆弱性评估中的空间指标、空间制图方法与空间对策等方面的研究进展,指明该领域已从单一视角逐步深入到气象学、医学、地理学等复合学科的交叉研究,地理学作为桥梁将气象学与医学有机结合,为脆弱性评估提供空间指标参数、为制图提供思路与方法,并提供空间对策连接规划和风险预警等实践工作。未来的研究展望包括:空间指标综合各学科研究需要、集成各学科优势进行构建,空间制图在社区小尺度到区域大尺度的耦合机理分析基础上探讨跨区域研究表达方式,空间对策针对不同风险人群采取差异化研究,为城市适应气候变化提供科学依据。  相似文献   

6.
To provide guides for exploration of porphyry copper mineralization at a district scale, we examine the spatial association between known porphyry copper deposits and geologic features in Benguet, Philippines. The spatial associations between the porphyry copper deposits and strike-slip fault discontinuities, batholithic pluton margins and porphyry plutons are quantified using weights of evidence modeling. In the training and testing district, the porphyry copper occurrences are associated spatially with strike-slip fault discontinuities, batholithic pluton margins and contacts of porphyry plutons within distances of 3 km, 2.25 km, and 1 km, respectively. In addition, the porphyry plutons are associated spatially with strike-slip fault discontinuities and contacts of batholithic plutons within a distance of 2.25 km and 3 km, respectively. Based on these significant spatial associations, predictive maps are generated to delineate zones favorable for porphyry copper mineralization and zones favorable for emplacement of porphyry plutons in Benguet province, Philippines. Validations of the predictive models demonstrate their efficacy in pointing to zones for subsequent follow-up exploration work.  相似文献   

7.
流域空间经济分析与西部发展战略   总被引:6,自引:2,他引:4  
本文在阐述流域空间经济的整体性和关联性、区段性和差异性、层次性和网络性、开放性和耗散性等特征的基础上 ,分析了流域开发的系统性、综合性、分区性、立体网络性和以水资源开发为中心的原则。以区域增长和空间经济发展模式为指导 ,以点轴开发为流域开发的重要组织形式 ,提出了依托大中城市 ,强化中心 ,通过“点”的经济技术力量向两翼腹地的辐射和扩散 ,又通过轴作用的向外 (上、下游 )传递 ,如此形成一种由点沿轴波及面的点线面渐进开发模式 ,最终使整个流域的国土资源和空间得到充分合理的全息开发利用。  相似文献   

8.
Ni  Xiaoming  Yang  Cixiang  Wang  Yanbin  Li  Zhongcheng 《Natural Resources Research》2021,30(2):1547-1559
Natural Resources Research - Accurate prediction of the spatial distribution of permeability of coal reservoirs using scare data from wells for coalbed methane exploration and development can lay a...  相似文献   

9.
基于GIS的地质勘察信息系统设计与实现   总被引:14,自引:0,他引:14  
从地质勘察领域分析入手,揭示三类主要数据内容及其内在联系,把握地质勘察领域的实质问题。采用信息系统实现关键技术与方法,建立地质勘察领域UML可视化需求模型,构建系统的三层架构体系,设计系统功能可视化组件图和系统数据库结构图。此研究内容与方法在深圳市地质勘察信息系统中成功实现,研究成果被列为科技项目成果推广应用。  相似文献   

10.
11.
空间信息分析技术   总被引:31,自引:5,他引:26  
在GIS技术日趋成熟和空间数据极大丰富的今天,通过分析空间数据探索空间过程机理正变得日益迫切。空间信息分析技术至少包括以下六个主要方面:(1)空间数据获取和预处理;(2)属性数据空间化和空间尺度转换;(3)空间信息探索分析;(4)地统计;(5)格数据分析;(6)复杂信息反演和预报。本文提出了解决具体应用问题一般的空间数据分析计算、结果解释和反馈程序。认为空间过程的一般共性和作为共同的研究对象,各种不同的方法技术最终可能导致空间数学(spatialmathematics)的产生,同时发展鲁棒的空间分析软件包对于普及空间数学是必要的。  相似文献   

12.
The evidential belief function (EBF) provides an adequate theoretical basis for managing uncertainties in exploration data integration. The EBF can be used to represent uncertainties in the reasoning process and provides the capability of distinguishing between lack of information and negative information. This capability is desirable when combining diverse data sets, which often vary in spatial resolution and spatial extent. The uncertainties associated with data and propositions can be represented naturally and consistently using belief functions. Hence, using the EBF approach can provide a realistic quantitative picture of the target proposition.  相似文献   

13.
Urban segregation has received increasing attention in the literature due to the negative impacts that it has on urban populations. Indices of urban segregation are useful instruments for understanding the problem as well as for setting up public policies. The usefulness of spatial segregation indices depends on their ability to account for the spatial arrangement of population and to show how segregation varies across the city. This paper proposes global spatial indices of segregation that capture interaction among population groups at different scales. We also decompose the global indices to obtain local spatial indices of segregation, which enable visualization and exploration of segregation patterns. We propose the use of statistical tests to determine the significance of the indices. The proposed indices are illustrated using an artificial dataset and a case study of socio‐economic segregation in São José dos Campos (SP, Brazil).  相似文献   

14.
The spatial distribution of discovered resources may not fully mimic the distribution of all such resources, discovered and undiscovered, because the process of discovery is biased by accessibility factors (e.g., outcrops, roads, and lakes) and by exploration criteria. In data-driven predictive models, the use of training sites (resource occurrences) biased by exploration criteria and accessibility does not necessarily translate to a biased predictive map. However, problems occur when evidence layers correlate with these same exploration factors. These biases then can produce a data-driven model that predicts known occurrences well, but poorly predicts undiscovered resources. Statistical assessment of correlation between evidence layers and map-based exploration factors is difficult because it is difficult to quantify the “degree of exploration.” However, if such a degree-of-exploration map can be produced, the benefits can be enormous. Not only does it become possible to assess this correlation, but it becomes possible to predict undiscovered, instead of discovered, resources. Using geothermal systems in Nevada, USA, as an example, a degree-of-exploration model is created, which then is resolved into purely explored and unexplored equivalents, each occurring within coextensive study areas. A weights-of-evidence (WofE) model is built first without regard to the degree of exploration, and then a revised WofE model is calculated for the “explored fraction” only. Differences in the weights between the two models provide a correlation measure between the evidence and the degree of exploration. The data used to build the geothermal evidence layers are perceived to be independent of degree of exploration. Nevertheless, the evidence layers correlate with exploration because exploration has preferred the same favorable areas identified by the evidence patterns. In this circumstance, however, the weights for the “explored” WofE model minimize this bias. Using these revised weights, posterior probability is extrapolated into unexplored areas to estimate undiscovered deposits.  相似文献   

15.
This study empirically investigates the potential of auditory displays for spatial data exploration, as an additional means to broaden the accessibility and dissemination of geographic information for a diverse body of users. In a mixed factorial experiment, three parameter mapping sonification methods are empirically evaluated to interactively explore discrete and continuous digital elevation models by auditory means. Contrasting prior sonification research, this study’s unique empirical evidence suggests that participants can indeed successfully interpret sonified displays containing continuous spatial data. Specifically, the auditory variable pitch leads to significantly better response accuracy, compared to the sound variable duration. Background and training has a weak effect on data interpretation performance with the auditory display. The more immersive the experienced soundscape, the better participants can interpret the sonified terrain. These encouraging empirical results indeed suggest that interactive auditory displays might offer additional means to disseminate spatial information, and to increase the accessibility to spatial data, beyond the currently dominant visual paradigm.  相似文献   

16.
伊洛河流域开发战略研究   总被引:3,自引:0,他引:3  
王兵  臧玲 《地域研究与开发》2007,26(6):53-56,74
伊洛河流域复杂的自然条件、丰富的自然资源以及悠久的开发历史,使其具有独特的人文环境和地域经济.基于伊洛河流域的基本特征和存在的主要问题,为实现流域可持续发展,提出了应坚持以经济发展优先、富县与富民相结合、各区段协调发展、经济发展与生态环境保护相协调等为基本原则,以优化农业空间生产结构、改善经济网络结构、合理开发自然资源、引导农村工业发展和积极开展生态旅游等为战略重点实施流域开发.  相似文献   

17.
社会经济统计数据空间化研究进展   总被引:1,自引:0,他引:1  
郭红翔  朱文泉 《地理学报》2022,77(10):2650-2667
社会经济统计数据通常是以各级行政区为单位的汇总数据,它虽然能反映统计单元之间的差异但却不能反映统计单元内部的异质性,在实际应用中,无法满足统计任意区域内的社会经济数据的需求,而社会经济统计数据空间化则是有效解决该问题的一条重要途径。本文对现有社会经济统计数据的空间化方法、社会经济统计数据空间化过程所依赖的辅助数据、现有主要的社会经济空间化数据产品进行了归纳总结,并从空间化方法的制约因素和改进方向、新型辅助数据的探索和多源辅助数据的综合利用、高时空分辨率和高精度数据产品研发3个方面展望了社会经济统计数据空间化的未来发展趋势。研究结果可为社会经济统计数据空间化方法的选择与改进、辅助数据的选择与综合利用、社会经济空间化数据产品的选择与改进提供参考。  相似文献   

18.
For public land management in Idaho and western Montana, the U.S. Forest Service (USFS) has requested that the U.S. Geological Survey (USGS) predict where mineral-related activity will occur in the next decade. Cellular automata provide an approach to simulation of this human activity. Cellular automata (CA) are defined by an array of cells, which evolve by a simple transition rule, the automaton. Based on exploration trends, we assume that future exploration will focus in areas of past exploration. Spatial-temporal information about mineral-related activity, that is permits issued by USFS and Bureau of Land Management (BLM) in the last decade, and spatial information about undiscovered resources, provide a basis to calibrate a CA. The CA implemented is a modified annealed voting rule that simulates mineral-related activity with spatial and temporal resolution of 1 mi2 and 1 year based on activity from 1989 to 1998. For this CA, the state of the economy and exploration technology is assumed constant for the next decade. The calibrated CA reproduces the 1989–1998-permit activity with an agreement of 94%, which increases to 98% within one year. Analysis of the confusion matrix and kappa correlation statistics indicates that the CA underestimates high activity and overestimates low activity. Spatially, the major differences between the actual and calculated activity are that the calculated activity occurs in a slightly larger number of small patches and is slightly more uneven than the actual activity. Using the calibrated CA in a Monte Carlo simulation projecting from 1998 to 2010, an estimate of the probability of mineral activity shows high levels of activity in Boise, Caribou, Elmore, Lincoln, and western Valley counties in Idaho and Beaverhead, Madison, and Stillwater counties in Montana, and generally low activity elsewhere.  相似文献   

19.
试论新经济发展条件下城市产业结构演进与空间结构变迁   总被引:3,自引:0,他引:3  
新经济是以知识和信息为基本生产要素.以智力资本创新为核心.以信息网络为基本生产工具的新经济形态。基于对新经济产业及其空间分布特征的探讨,认为在新经济发展条件下.城市产业结构有着螺旋式上升的轻型化发展趋势,城市空间结构在整体扩散的同时.中心城区蕴含着聚集产业和人口的引力,并从宏观、中观、微观三个层面给出对城市规划的启示。  相似文献   

20.
On Blind Tests and Spatial Prediction Models   总被引:3,自引:0,他引:3  
This contribution discusses the usage of blind tests, BT, to cross-validate and interpret the results of predictions by statistical models applied to spatial databases. Models such as Bayesian probability, empirical likelihood ratio, fuzzy sets, or neural networks were and are being applied to identify areas likely to contain events such as undiscovered mineral resources, zones of high natural hazard, or sites with high potential environmental impact. By processing the information in a spatial database, the models establish the relationships between the distribution of known events and their contextual settings, described by both thematic and continuous data layers. The relationships are to locate situations where similar events are likely to occur. Maps of predicted relative resource potential or of relative hazard/impact levels are generated. They consist of relative values that need careful quantitative scrutiny to be interpreted for taking decisions on further action in exploration or on hazard/impact mitigation and avoidance. The only meaning of such relative values is their rank. Obviously, to assess the reliability of the predicted ranks, tests are indispensable. This is also a consequence of the impracticality of waiting for the future to reveal the goodness of our prediction. During the past decade only a few attempts have been made by some researchers to cross-validate the results of spatial predictions. Furthermore, assumptions and applications of cross-validations differ considerably in a number of recent case studies. A perspective for all such experiments is provided using two specific examples, one in mineral exploration and the other in landslide hazard, to answer the fundamental question: how good is my prediction?  相似文献   

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