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61.
基于普适性单通道算法,利用2005年5月6日的TM数据反演北京市区的实际地表温度。在此基础上,分析了北京市区的热环境特征、热岛分布的位置。运用GIS空间分析工具,分析了地表温度与地形特征和地表覆盖类型之间的关系。结果表明,北京市热岛分布具有环状和带状分布特征,高程较低处和坡度较小处更容易形成热岛中心,不同地表覆盖类型的热特征具有显著的差异。 相似文献
62.
根据1985年和2000年TM影像进行人工解译,提取各土地利用类型数据,计算了研究区的斑块指数、多样性指数、优势度、破碎度、分维度及形状指数等景观格局指标,并进行分析。结果表明,研究区有林地在整体景观格局上起基质作用;各主要景观类型均具有较大的边界曲折性;在研究时段内斑块总数下降,多样性也下降,反映土地利用向大景观要素集中。 相似文献
63.
煤的成因类型通过煤的有机显微组成、矿物成分等来体现。从微观研究的角度出发,以各子样的显微煤岩组分统计值、镜惰比(V/I)、骨基比(F/M)、矿物质含量为依据,对西山煤田屯兰煤矿7号煤进行成因类型划分,分为4类6型,即Ⅰ-①、Ⅲ-①、Ⅲ-②、Ⅳ-①、Ⅳ-②、Ⅴ-①。自下而上对煤层划分了23个成因分层。7煤层以Ⅳ类成因类型为主,沉积了覆水森林沼泽环境。 相似文献
64.
以胶州湾及周边海岸带为研究区,采用Landsat 7 ETM+数据,提出一种基于à trous小波变换的全色图像和多光谱图像融合改进算法。对全色图像和多光谱图像进行适当层数的小波分解,多光谱图像的低频部分采用全色图像和其低频分量的比来调制; 最高分解层外的其余分解层采用多光谱图像和全色图像在该层分解系数的加权和,加权系数由局部区域能量比来确定; 最高分解层则采用绝对值最大准则。实验表明,该方法得到的图像可提高空间分辨率,对多光谱图像的光谱信息扭曲也较小,为提高海岸带地物分类和信息提取精度奠定了基础。 相似文献
65.
Maximum likelihood (ML) and artificial neural network (ANN) classifiers were applied to three Landsat Thematic Mapper (TM) image sub-scenes (termed urban, agricultural and semi-natural) of Cukurova, Turkey. Inputs to the classifications comprised (i) spectral data and (ii) spectral data in combination with texture measures derived on a per-pixel basis. The texture measures used were: the standard deviation and variance and statistics derived from the co-occurrence matrix and the variogram. The addition of texture measures increased classification accuracy for the urban sub-scene but decreased classification accuracy for agricultural and semi-natural sub-scenes. Classification accuracy was dependent on the nature of the spatial variation in the image sub-scene and, in particular, the relation between the frequency of spatial variation and the spatial resolution of the imagery. For Mediterranean land, texture classification applied to Landsat TM imagery may be appropriate for the classification of urban areas only. 相似文献
66.
利用遥感技术动态监测城镇扩展己成为一个重要的研究领域和应用方向。本论文基于多源多时相遥感影像和地形数据,以福建漳州市区为示范区,探讨城镇建筑用地扩张遥感动态监测的方法。作者认为基于ASTER影像,综合利用非监督分类、多时相植被指数、城镇建筑用地的地形分布等知识建立分类决策规则,可以有效提取城镇建筑用地信息,准确度不低于90%。同时提出利用城镇建筑用地时空分布知识、多时相植被指数知识,改进TM三指数城镇建筑用地提取方法的思路,最终提取的城镇建筑用地信息满足城镇建筑用地动态变化分析的精度要求。 相似文献
67.
比值—特征主成分混合分析提取金矿蚀变信息:以赣南遂川地区为例 总被引:1,自引:0,他引:1
在分析与金矿有关的两类蚀变岩的TM波谱特征的基础上,以赣南遂川地区为实验区,利用比值-特征主成分混合分析进行了金矿蚀变岩信息提取,为找矿预测和野外工作指明了方向。 相似文献
68.
Mingcai Yan Chunshu Wang Tiexin Gu Qinghua Chi Zhong Zhang 《Geostandards and Geoanalytical Research》1998,22(2):235-246
Unlike the situation for other elements, few reference materials certified for the platinum-group elements are currently available. Therefore, the GPt1-7 series of PGE geochemical CRMs, prepared by the IGGE, represent an important addition and comprise a range of matrix types, including a soil, stream sediment, Mg-rich ultramafic rock, Fe-rich ultramafic rock, platinoid ore depleted in Cu, Ni and Fe, and a chromitite. The concentration of PGE in these samples ranges over 4-5 orders of magnitude and the samples were shown to have good homogeneity as assessed by a variance test. Analytical methods based on different principles were used in sample certification, including several fire assay and wet chemical procedures used for decomposition and preconcentration. Certified values for the elements Pt, Pd, Os, Ru, Ir, Rh and Au were determined by AAS, catalytic colourimetry (COL), catalytic polarography (POL), atomic emission spectrometry (AES), ICP-MS and NAA. Recently, the GPt1-7 samples were approved as national primary CRMs by the State Bureau of Technical Supervision of China. 相似文献
69.
Kimberly K. Takagi Phaothep Cherdsukjai Izumi Mimura Yuka Yano Kanjana Adulyanukosol Makoto Tsuchiya 《Estuarine, Coastal and Shelf Science》2010
This study aimed to elucidate Dotilla myctiroides (H. Milne-Edwards) food resources and how the soldier crab influences the organic matter composition on the intertidal flat. A preliminary assessment of D. myctiroides size, sex, and population distribution was conducted to clarify the characteristics of the inhabiting population. Overall, D. myctiroides size and abundance was normal across the tidal flat area. Comparison of different sediment types from the soldier crab habitat (surface sediments, igloos, burrow lining, burrow pellets, feeding pellets, and feces) using the fatty acid (FA) analysis technique revealed D. myctiroides removes organic matter via the significantly lower contributions of polyunsaturated FAs, essential FAs, and dinoflagellates in the feeding pellets. Dotilla myctiroides tissue analysis of the hepatopancreas and hindgut in individuals that had been starved for 24 h confirmed not only the consumption of dinoflagellates, but diatoms and macroalgae as well. In addition, the FA metabolism within the digestive system implied the ability of the soldier crab to synthesize highly unsaturated FAs (HUFAs) such as 20:4n–6, 20:5n–3 and 22:6n–3. 相似文献
70.
Ruiqing QIE Linfu XUE Shixiang LIU Yunliang YU 《东北亚地学研究》2007,10(1):88-94
The authors took the ETM + multi-spectra data as the data information and correlation coefficient for each band and carried out their information volume statistics. According to certain criteria, the authors also determined the optimum band-combined image. The image clarity is improved by various enhancements and fusions method. Based on remote sensing geological interpretation in detail, the relationship between remote sens- ing geological characters and gold mine were analyzed systemically. Using all kinds of remote sensing structure information, combining other research data, the authors determined mainly ore-controlling ore structure. Several prospective areas of gold ores were determined and furthermore significant finding mine target areas was confirmed. 相似文献