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131.
GIS空间分析与模糊综合评判在银行ATM网点选址中的应用   总被引:4,自引:1,他引:3  
黎雯  周廷刚  张伟 《测绘科学》2008,33(1):229-231,237
空间分析是GIS的核心和灵魂,是GIS区别于一般信息系统的主要标志之一。运用GIS空间分析中的叠置分析、缓冲区分析、网络分析等功能对自动柜员机(ATM)网点进行选址,应用模糊综合评判模型对选址区位评价确定出ATM布放的最终布局,并通过实例验证该方法能为在ATM网点选址中提供决策依据,最后探讨了今后研究的方向。  相似文献   
132.
鄂尔多斯盆地合水地区长8储层特低渗透成因分析与评价   总被引:12,自引:6,他引:6  
鄂尔多斯盆地合水地区长8储层的物性总体较差,发育粒间孔、溶孔,孔隙结构类型属小孔隙、微细喉道和微喉道型;分析表明其特低渗透成因主要受沉积作用和成岩作用的共同影响,不同沉积微相储层的物性差异较大,柔性组分含量高、粒度细和成分成熟度较低是造成储层特低渗透特征的主要原因;同时成岩压实、胶结作用使得储层的孔隙度减小、渗透性变差,而溶蚀作用和少量成岩微裂缝的产生又在很大程度上改善了储层的特低渗透性能;水下分流河道与河口坝砂体是研究区主要储层的分布相带.  相似文献   
133.
Studies on rain-runoff process in the peripheral mountainous area of the Sichuan Basin, which is regarded as a key ecological shelter, will contribute to flood control and environmental protection for the Upper Yangtze River Basin. In two typical catchments--the Fujiang River Catchment and the Wujiang River Catchment, rainfall simulations have been conducted to study the rain-runoff processes of yellow soil and limestone soil in three types of land use--forestland, farmland and grassland. Results showed that (1) within the same rainfall process, overland flow occurs first on farmland, then on grassland, and finally on forestland; (2) soil surface coverage has a great impact on the occurrence and amount of overland flow. The runoff amount can increase 2-4 times after the coverage is removed; (3) the infiltration before the occurrence of overland flow will decrease because of higher gravel contents of soil, but it takes no effect on infiltration once overland flow becomes stable; (4) the runoff coefficient of the limestone soil forestland is greater than that of the yellow soil forest land, but less than that of the farmland; (5) three empirical infiltration models, including Horton' model, Kostiakov' model, and modified Kostiakov' model, were compared by using the observed results under rainfall simulation. The results showed that the Kostiakov' model performed better than both the Horton' model and modified Kostiakov model. According to the results of this research, the Kostiakov's model can be used to simulate rainfall infiltration when water erosion is modeled in the peripheral mountainous area of the Sichuan Basin.  相似文献   
134.
探讨在ArcGIS环境下利用1:5万DLG数据库直接生成地形图的若干关键技术,如定制1:5万DLG符号库、符号配置,并给出地形图生产的完整的工艺流程,这样能够缩短1:5万地形图的成图周期,提高工作效率。  相似文献   
135.
The northern margin of the Qaidam Basin is one of the main oil-gas exploration areas in western China, where source rocks are composed mostly of Middle and Lower Jurassic dark mud shale, carbargillite and coal. A large number of subsurface and outcrop samples differing in lithology with different types of organic matter were selected for resource evaluation, research and calculation. And among them, 13 samples were used for simulation experiment on hydrocarbon generating potential of various source rocks. At first, two kinds of heating modes were compared through simulation experiment, including single temperature-step heating and continual heating. Perhaps, the process of hydrocarbon generation and expulsion occurred naturally between a close system and an open system. In addition, the first heating mode was convenient, and all its reaction products were involved in the whole thermal evolution, and the final simulation experimental results were basically in consistency with the natural evolution trend Therefore, the first heating mode was adopted and the hydrocarbon yield of every sample was worked out. According to the type and lithology of organic matter and the hydrocarbon yield of samples for simulation experiment, hydrocarbon generation and expulsion mode with three kinds of lithology and five types of source rock has been established to provide the basis for hydrocarbon generation evaluation, research and resource calculation.  相似文献   
136.
The Baimazhai nickel deposit, Yunnan Province, China, is located in the southern part of the Sanjiang (Tri-river) alkali-rich intrusive rock belt (Sanjiang ARIR). In this paper was conducted ^40Ar-^39Ar dating of two phlogopites in lamprophyres which are, as dikes, widely distributed in the orefield, and two plateau ages were acquired, i.e., 32.46±0.62 Ma and 32.01±0.60 Ma, respectively (averaging 32.23±0.60 Ma). The ages are obviously younger than those of the ore-hosted complex and mineralization of the Baimazhai nickel deposit. In combination with the characteristics, it is indicated that lamprophyres in the orefield and those in the Sanjiang ARIR are similar in tectonic setting, mineral assemblage and geochemistry. It is considered that lamprophyres in the orefield are the important component of the Sanjiang ARIR, and the lamprophyres and ore-hosted complex in the orefield represent the products of two times of different magmatic activity from different mantle sources. On the other hand, the age of lamprophyres in the orefield is older than that of the strike-slip shearing of the Ailaoshan-Honghe fault belt, suggesting that the strike-slip shearing of the Ailaoshan-Honghe fault belt is not the factor leading to magmatic activity of lamprophyres in the orefield, while it is more possible that magmatic activity of the Sanjiang ARIR promoted strike-slip shearing of the fault belt.  相似文献   
137.
The significance of crop yield estimation is well known in agricultural management and policy development at regional and national levels. The primary objective of this study was to test the suitability of the method, depending on predicted crop production, to estimate crop yield with a MODIS-NDVI-based model on a regional scale. In this paper, MODIS-NDVI data, with a 250 m resolution, was used to estimate the winter wheat (Triticum aestivum L.) yield in one of the main winter-wheat-growing regions. Our study region is located in Jining, Shandong Province. In order to improve the quality of remote sensing data and the accuracy of yield prediction, especially to eliminate the cloud-contaminated data and abnormal data in the MODIS-NDVI series, the Savitzky–Golay filter was applied to smooth the 10-day NDVI data. The spatial accumulation of NDVI at the county level was used to test its relationship with winter wheat production in the study area. A linear regressive relationship between the spatial accumulation of NDVI and the production of winter wheat was established using a stepwise regression method. The average yield was derived from predicted production divided by the growing acreage of winter wheat on a county level. Finally, the results were validated by the ground survey data, and the errors were compared with the errors of agro-climate models. The results showed that the relative errors of the predicted yield using MODIS-NDVI are between −4.62% and 5.40% and that whole RMSE was 214.16 kg ha−1 lower than the RMSE (233.35 kg ha−1) of agro-climate models in this study region. A good predicted yield data of winter wheat could be got about 40 days ahead of harvest time, i.e. at the booting-heading stage of winter wheat. The method suggested in this paper was good for predicting regional winter wheat production and yield estimation.  相似文献   
138.
传统的机械式电位器控制电路难以满足高精度的信号调节要求,而且具有调节不方便、体积大、重复性差等弱点;为此,利用USB即插即用的优点,设计了基于USB的DCP控制电路;这里详细介绍了USB设计模块、DCP控制模块、固件程序设计和应用程序设计;测试结果表明:该设计是成功的,在输入1 V的正弦信号情况下,输出信号的调节精度可达1 mV,实现了输出信号的高精度调节,具有一定应用前景。  相似文献   
139.
潜水面对储层压力的作用机制   总被引:5,自引:0,他引:5  
潜水面与地表不一致会使储层压力产生异常,给煤层气勘探开发造成影响。从异常压力的成因机理入手,应用理论分析与实例解剖相结合的方法,通过不同系统中潜水面对储层压力的作用机制研究,分析了开放系统中区域潜水面变化所引起的储层压力变化规律,反映了盆地水动力场作用下的储层压力系统的动态演化过程,指出潜水面变化是储层异常压力形成的重要机制。  相似文献   
140.
高光谱遥感将反映目标辐射属性的光谱信息与反映目标空间几何关系的图像信息有机地结合在一起,能够实现地面目标的精细分类识别。FCM是一种有效的聚类算法,但存在相似性测度模型单一、分类精度的提高受到限制等问题。文中结合高光谱影像的技术特点,综合考虑光谱曲线的形状、地物辐射亮度及其权重,提出可以更好描述光谱向量之间的相似性的距离测度,并将其引入到FCM聚类模型中。聚类分析试验结果表明:通过改进和优化相似性测度的FCM,可以显著提高高光谱影像聚类精度。  相似文献   
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