基于直方图的遥感图像相似性检索方法比较

相似性度量是用于研究多源数据之间相似程度的，是对空间数据进行模式识别的基础。通过单波段遥感图像的检索对两组直方图相似性检索方法进行了实验研究，即基于特征向量的相似性度量和基于概率的相似性度量。实验中发现第一组相似度量中有两种以往较少用于遥感图像检索的方法表现出色，它们分别是，统计距离和相似夹角余弦度量。第二组实验中，针对其中包含较明显的目标物体且背景较为单一的遥感图像（其直方图可看作混合高斯分布），在类别可分离判据的基础上，根据K-近邻法则提出了一种计算该类图像之间相似值的方法。实验结果表明基于K-近邻法则的计算方法行之有效。所得出的结论将对多源数据分析中相似性度量的理解与选择有积极意义。     

引力向量及梯度张量在坐标系之间的变换

引力向量和引力梯度张量在局部和全局坐标系间的转换过程是对卫星重力梯度测量进行模拟研究的主要手段和重要步骤.提出了利用计算机符号运算辅助推导该转换过程的新思想.首先通过对该过程进行分析,指出其运算繁琐复杂;然后通过对理论推导过程的分解,确定了引力向量和引力梯度张量在局部和全局坐标系之间转换的各关键步骤;并借助于计算机符号运算实现了这一转换过程的计算机推演,成功地得到了完整的符号公式结果.所编写的符号推演程序在多台计算机的多种平台上获得了一致的结果.实验结果表明,计算机符号运算对于公式体系繁杂的卫星重力学理论研究来说具有极大的增效作用.     

一种建筑物倾斜测量的方法

本文提出一种基于无反射棱镜全站仪的建筑物倾斜测量方法,通过推导、精度分析和实例计算,证明了此方法的可行性,具有一定的实用意义.     

逆气压改正对卫星测高数据反演潮汐参数的影响

定量分析了逆气压改正对各主分潮潮汐参数反演的影响。结果表明,逆气压改正对Sa的反演结果影响最大,在Sa的实际振幅中,气压变化的平均贡献比率为42%,气压变化使Sa的迟角减小了约27°,而对其他主分潮的影响可忽略不计。建议在应用卫星测高数据时,不加逆气压改正,但在数据处理时,需加Sa分潮的改正。     

贵州西部中、上二叠统界线附近风化壳类型及成矿作用

贵州西部中、上二叠统界线附近普遍存在不整合面,在不整合面上往往发育厚度不等的风化壳。风化壳主要可归纳为三种类型:茅口组顶部的喀斯特漏斗、洼地中堆积的红粘土风化壳,锰质(铁质)风化壳,峨眉山玄武岩喷发间断面上或玄武岩顶部与龙潭组(宣威组)之间的的高铝高岭石风化壳。喀斯特侵蚀面上的红土风化壳是红土型金矿的赋存层位,峨眉山玄武岩喷发间断面上的高铝高岭石风化壳是铜矿、铝土矿赋存层位,喀斯特侵蚀面上的锰质(铁质)风化壳是锰矿、铁矿赋存层位,而玄武岩顶部与龙潭组(宣威组)之间的高岭石粘土风化壳是稀土、硫铁矿、铝土矿赋存层位。中、上二叠统界线附近风化壳对金、铜、铝土、硫铁、锰和稀土有明显的控制作用。     

被动微波反演裸露区土壤水分综述

被动微波具有全天候、穿透性以及不受云的影响等特征,使其在反演土壤水分时具有很大的优势。通过研究发现,被动微波遥感是反演土壤水分的各种技术中最有效的方法之一。概括了主要的被动微波传感器并从被动微波遥感的原理出发,针对被动微波遥感裸露区地表随机粗糙面的模型以及土壤水分反演算法作了简要介绍。     

中国西部道路交通开发的地质环境及可行性认识

宏观上论述了我国西部道路交通开发中地质环境基本特点、主要工程地质问题及工程可行性,并着重指出,地形复杂、地壳强活动、滑坡泥石流、冻土和风沙等灾害构成了交通开发中施工、养护的突出问题,部分干旱区水源匮乏矛盾尤为突出,但工程地质环境仍具可选择的条件。     

内蒙古耕地重心移动及其驱动因子分析

简单回顾了内蒙古垦荒历史,并用内蒙古自治区近５０年的统计数据计算出１９４９年～１９９６年不同年份的全区耕地重心及人口重心,在此基础上得到了内蒙古耕地重心及人口重心均向东北方向移动的结论,分析了耕地重心移动的驱动因子,提出了土地持续利用的几点建议。     

南极海冰变化异常与全球海平面变化(英)

In this paper, the long-term variation trend of the Antarctic sea ice in 1973～1994 and the inter-decade variation rule of the global sea level are analyzed. It is foundthat, the Antarctic sea ice area in 1980's was significantly less than in 1970's but with regional difference:decreasing in Regions Ⅰ, Ⅱ, and Ⅲ, and increasing in Region Ⅳ, the average global sea levelheightvalue in 1980's was also significantly higher than in 1970's but also with very large regional difference.Connecting variation of both to analyze their physical mechanism, it is pointed that, the accumulated seaice anomaly value in 1980's less than in 1970's means a global climate warming, the sea watertemperature and air temperature rising, sea water volume expanding, and more icebergs transportingfrom the ice cover on the Antarctic continent to ocean in the warmer years. As a result, the global sealevel raised significantly with the global average sea level value in 1980's was 22 mm higher than in 1970's. The Sea Level Raising (SLR) distributed uneven. It is especially true in the Pacific Ocean andAtlantic. This kind of uneven SLR distribution closely relates to, or is introduced by the uneven sea ice change of the Antarctic Regions.     

气候系统内极区热汇与热带海洋热源之间的相互作用(英)

The anomalous change of two polar sea ice and tropical ocean SST is a very important index for global climate monitoring and prediction. In this paper, the wave resonance principle is used to calculate month by month running cross couple correlation coefficient time series between sea ice in different sea area of two Polars, as well as between them and five elements of E1 Nino events, to analyze their variation features, and to find out their resonance periods. The resonance period of two waves is just the strongest interaction period.Some results are concluded as follows. 1) The Arctic sea ice to the Pacific-side (NPI1) and Atlantic-side (NP12) show a strong positive-negative feedback impact each other to the Antarctic Ross Sea ice (SPI2) with equal intensity. 2) Both NPI1 and NPI2 give a strong positive and negative feedback to the Antarctic Wedded Sea ice (SPI3) while it is rather weak in convercse status. It means that, the Arctic sea ice plays a leading and controlling role on the Wedded Sea ice. 3) SST of Nino 4 area in thecentral equatorial Pacific has a best resonance period with SPI2 with cycle period of 132 months. It closely relates to quasi-11 years oscillation period of both SST of Nino 4 area and SPI2. SST of Nino 4 has also a resonance period to SPI3 with cycle of 61 months. There also exist strong interaction periods between the Antarctic sea ice and other elements of ENSO event but weaker than SST of Nino 4 area.