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基于ArcGIS的空间自相关分析模块的开发与应用 总被引:1,自引:0,他引:1
针对目前GIS的空间分析能力,利用ArcObjects开发了空间自相关分析模块。模块包括空间权值矩阵建立、全局空间自相关分析、局部空间自相关分析三方面的功能,并可以嵌入到ArcGIS系统中。论文介绍了空间自相关分析的基本概念、空间自相关分析模块的设计与开发,并演示了模块的应用。 相似文献
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周玲霞李红张少杰黄振宇 《地理空间信息》2016,(6):59-61
防汛抢险情况复杂,时效性要求极高。为了高效地进行防汛抢险,基于GIS技术开发了防汛抢险信息系统,该系统包括等深线叠加分析、断面分析、冲淤分析、工程设计等功能。系统在2013年长江七坝岸段崩岸抢险中发挥了巨大作用,分析了险情的原因,设计了初步方案,及时为抢险工作提供了信息,减少了损失。还对七坝工程完工后进行效果分析,显示工程效果较好。 相似文献
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供水管网地理信息系统中爆管分析的算法研究 总被引:1,自引:0,他引:1
爆管关阀分析是供水管网地理信息系统中重要的空间分析功能之一,目前已建系统的爆管分析功能存在着算法繁琐或功能简单、不具通用性等缺点。本文以高质量的源数据为基础,根据系统和爆管分析的需求建立合理的数据模型,设计了爆管关阀分析算法,该算法克服现有算法的不足,剔除了可关可不关的阀门,得到正确、经济的关阀门方案,并列出了受影响的用户。将此设计方案应用于"新疆石油管理局供水地理信息系统"中,成功地实现了爆管分析,体现出了该算法简洁、高效、准确、通用的优越性。 相似文献
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城区土地定级研究是进行城区地价评估的基础.运用特尔菲法选取定级因素、因子并确定权重;借助GIS强大的空间数据和属性数据管理、分析功能,计算影响因素、因子的分值和定级单元的分值,并进一步对土地级别进行了划分;通过GIS的制图功能对定级结果以图形化的方式输出. 相似文献
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空间数据精度的检查和评价方法研究 总被引:1,自引:0,他引:1
从GIS空间数据精度出发,论述了空间数据误差的影响因素,提出空间数据精度的评价方法和确定空间数据精度实际检查过程中应注意的问题,并以实际工作成果说明本文提出的空间数据精度检查及评价的效果。 相似文献
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The quality and yield of tea depends upon management of tea plantations, which takes into account the factors like type, age of plantation, growth stage, pruning status, light conditions, and disease incidence. Recognizing the importance of hyperspectral data in detecting minute spectral variations in vegetation, the present study was conducted to explore applicability of such data in evaluating these factors. Also stepwise discriminant analysis and principal component analysis were conducted to identify the appropriate bands for accessing the above mentioned factors. The Green region followed by NIR region was found as most appropriate best band for discriminating different types of tea plants, and the tea in sunlit and shade condition. For discriminating age of plantation, growth stage of tea, and diseased and healthy bush, Blue region was most appropriate. The Red and NIR regions were best bands to discriminate pruned and unpruned tea. The study concluded that field hyperspectral data can be efficiently used to know the plantation that need special care and may be an indicator of tea productivity. The spectral signature of these characteristics of tea plantations may also be used to classify the hyperspectral satellite data to derive these parameters at regional scale. 相似文献
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《地理信息系统科学与遥感》2013,50(3):371-393
This study uses a multiple linear regression method to composite standard Normalized Difference Vegetation Index (NDVI) time series (1982-2009) consisting of three kinds of satellite NDVI data (AVHRR, SPOT, and MODIS). This dataset was combined with climate data and land cover maps to analyze growing season (June to September) NDVI trends in northeast Asia. In combination with climate zones, NDVI changes that are influenced by climate factors and land cover changes were also evaluated. This study revealed that the vegetation cover in the arid, western regions of northeast Asia is strongly influenced by precipitation, and with increasing precipitation, NDVI values become less influenced by precipitation. Spatial changes in the NDVI as influenced by temperature in this region are less obvious. Land cover dynamics also influence NDVI changes in different climate zones, especially for bare ground, cropland, and grassland. Future research should also incorporate higher-spatial-resolution data as well as other data types (such as greenhouse gas data) to further evaluate the mechanisms through which these factors interact. 相似文献
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基于特征价格模型的农村土地征收价格影响因素研究 总被引:3,自引:0,他引:3
在分析我国农村土地征收市场现状和农村土地征收价格影响因素的基础上,以天津市环城3个近郊区为例,收集市场案例256宗,选择影响因素13个,采用SPSS12.0进行多元回归,构建了两种形式的特征价格模型,重点分析了影响因素对价格的作用机制. 相似文献
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基于蒸渗仪的蒸散量时间尺度扩展方法对比 总被引:7,自引:2,他引:5
蒸散量(ET,Evapotranspiration)时间尺度扩展方法模拟效果受多种因素影响。本文利用蒸渗仪实测的冬小麦生育期ET数据,对比分析基于蒸发比、作物系数和冠层阻力的不同ET时间尺度扩展方法的估算效果。结果表明,对小时到日尺度的ET时间扩展而言,利用上午时段(10:00-11:00)的ET实测数据,基于冠层阻力的日ET尺度扩展值估算效果要优于基于蒸发比和作物系数的效果,而利用下午时段(14:00-15:00)的ET实测数据,基于作物系数的日ET尺度扩展值估算效果要优于基于蒸发比和冠层阻力的效果,对于从典型日到生育期尺度的ET时间扩展,基于作物系数的生育期ET尺度扩展值估算效果要好于基于蒸发比和冠层阻力的效果。应根据当地的气候气象条件、作物种植状况、时间尺度扩展类型、土壤水分、ET观测设施种类等因素,择优适宜的ET时间尺度扩展方法。 相似文献
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Estimating tropical biomass is critical for establishment of conservation inventories and landscape monitoring. However, monitoring biomass in a complex and dynamic environment using traditional methods is challenging. Recently, biomass estimates based on remotely sensed data and ecological variables have shown great potential. The present study explored the utility of remotely sensed data and topo-edaphic factors to improve biomass estimation in the Eastern Arc Mountains of Tanzania. Twenty-nine vegetation indices were calculated from RapidEye data, while topo-edaphic factors were taken from field measurements. Results showed that using topo-edaphic variables or vegetation indices, biomass could be predicted with an R2 of 0.4. A combination of topo-edaphic variables and vegetation indices improved the prediction accuracy to an R2 of 0.6. Results further showed a decrease in biomass estimates from 1162 ton ha?1 in 1980 to 285.38 ton ha?1 in 2012. This study demonstrates the value of combining remotely sensed data with topo-edaphic variables in biomass estimation. 相似文献