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21.
以大庆市湿地为研究对象,以地理信息系统和遥感技术为技术平台,介绍了湿地环境因子研究工作程序及湿地现状类型分布研究,分析了地理信息系统和遥感技术在湿地资源研究中的地位和作用,从而为GIS与RS技术在湿地资源应用研究中提供理论支持。  相似文献   
22.
首先对WebGIS的发展状况进行了分析,然后介绍了Web Services的工作原理,给出了面向Geo-Services的城市空间信息基础设施建设的结构模型,并依据该模型对北京市基础地理信息数据库集成项目进行了典型研究.  相似文献   
23.
地铁隧道结构变形监测信息管理系统的开发   总被引:2,自引:0,他引:2  
地铁隧道结构变形监测的特殊性、周期性和长期性,使其信息量非常庞大.信息管理是地铁隧道结构变形监测中一项重要的工作,现有的管理方式效率很低.为了高效、准确地管理监测信息,及时分析预报地铁隧道结构的稳定状况,本文结合南京地铁运营期隧道结构变形监测实例,开发了一套具有变形监测资料存储、预处理、管理分析、可视化分析、预测预报及限值预警等功能的信息管理系统,保证了准确及时快速的数据处理和信息反馈,具有良好的运用和推广前景.  相似文献   
24.
Many decision-making processes in the Earth sciences require the combination of multiple data originating from diverse sources. These data are often indirect and uncertain, and their combination would call for a probabilistic approach. These data are also partially redundant with each other or with all others taken jointly. This overlap in information arises due to a variety of reasons—because the data arises from the same geology, because they originate from the same location or the same measurement device, etc. The proposed tau model combines partially redundant data, each taking the form of a prior probability for the event being assessed to occur given that single datum. The parameters of that tau model measure the additional contribution brought by any single datum over that of all previously considered data; they are data sequence-dependent and also data value-dependent. Data redundancy depends on the sequence in which the data is considered and also on the data values themselves. However, for a given sequence, averaging the tau model parameters over all possible data values leads to exact analytical expressions and corresponding approximations and inference avenues. Information on multiple-point connectivity of permeability arrives from core data, well-test data and seismic data which are defined over varying supports with complex redundancy between these information sources. In order to compute these tau weights for determining connectivity, one needs a model of data redundancy, here expressed as a vectorial training image (Ti) constructed using a prior conceptual knowledge of geology and the physics of data measurement. From such a vectorial Ti, the tau weights can be computed exactly. Neglecting data redundancy leads to an over-compounding of individual data information and the possible risk of making extreme decisions.  相似文献   
25.
Singular physical or chemical processes may result in anomalous amounts of energy release or mass accumulation that, generally, are confined to narrow intervals in space or time. Singularity is a property of different types of non-linear natural processes including cloud formation, rainfall, hurricanes, flooding, landslides, earthquakes, wildfires, and mineralization. The end products of these non-linear processes can be modeled as fractals or multifractals. Hydrothermal processes in the Earth’s crust can result in ore deposits characterized by high concentrations of metals with fractal or multifractal properties. Here we show that the non-linear properties of the end products of singular mineralization processes can be applied for prediction of undiscovered mineral deposits and for quantitative mineral resource assessment, whether for mineral exploration or for regional, national and global planning for mineral resource utilization. In addition to the general theory and framework for the non-linear mineral resources assessment, this paper focuses on several power-law models proposed for characterizing non-linear properties of mineralization and for geoinformation extraction and integration. The theories, methods, and computer system discussed in this paper were validated using a case study dealing with hydrothermal Au mineral potential in southern Nova Scotia, Canada.  相似文献   
26.
We report on an objective methodology, referred to as intrinsic sample methodology, for the delineation of exploration target areas or resource areas for assessment. Important features of the methodology include (1) identification of recognition criteria for critical genetic factors, (2) synthesis of new variables from enhanced geodata, (3) estimation of logit probability models, and (4) cutting of estimated logit probabilities to delineate exploration targets or resource areas. The methodology is demonstrated on the Walker Lake quadrangle of Nevada and California.  相似文献   
27.
本文初步研究了遥感、GIS和制图一体化实用技术方法。对黄土丘陵区和沙漠地区TM数据进行了特征信息分析;给出了分层分类和GIS辅助分类结果;经模糊推理和人机交互修改,将提“纯”的遥感专题数据作为GIS的动态信息源,对GIS进行扩充与更新;最后在GIS支持下分层提取专题图并进行辅助制图。  相似文献   
28.
The purpose of this study is to develop a geotechnical microzonation model using Geographical Information Systems (GIS) based on Multicriteria Decision Analysis (MCDA). As study area, the Eskişehir downtown area has been chosen. Eskişehir is one of the most rapidly growing cities in central Turkey. The model inputs include slope, flood susceptibility, soil, depth to groundwater table, swelling potential, and liquefaction potential. The weight and rank values are assigned to the layers and to the classes of each layer respectively. The assignment of the weight/rank values and the analysis are realized by the application of two different decision models, namely Simple Additive Weighting (SAW) and Analytic Hierarchy Process (AHP) methods. The geotechnical microzonation maps prepared as outputs of these methods are found to be consistent with each other and confirmed by the experts within the study area. The geotechnical microzonation map prepared using the AHP method is recommended as the final map of the study.  相似文献   
29.
城市信息化是中国城市发展的新主题与新动力,是解决目前我国城市发展中诸多难题的重要途径。本文首先对比了数字城市和信息城市,然后指出了建设信息城市的迫切性和重要性,最后提出了城市信息科学的学科范畴。  相似文献   
30.
基于GIS的城镇土地定级信息系统建模方法探讨   总被引:2,自引:0,他引:2  
基于GIS的城镇土地定级信息系统在建设过程中,定级方法确定、定级单元大小确定和定级因素/子权重值的生成是关键,且三者都具有不同的确定方法,因此选择什么样的方法决定了系统建立的优劣。本文着重归纳、总结了城镇土地定级信息系统定级方法,通过对比分析,探讨了最优定级方法、最优网格单元大小划分方法和最优因素/子权重值计算方法。  相似文献   
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