泰国普吉岛上的两种含锡伟晶岩

对泰国普吉岛上的几个锡矿进行的研究表明,含锡伟晶岩有两个主要类型.钽-铌-锡伟晶岩以铌铁矿-钽铁矿、铌钇矿及含钽和钽铁矿出溶体的锡石为特征.伴生的锆石晶体是一种不透明的褐色短棱柱     

经济新常态下我国土地利用形势分析

本文以数据为基础,分析了近年来我国经济新常态下土地利用的总体形势,包括:耕地面积减速趋缓,耕地质量有所提升;伴随经济增速放缓和发展方式转变,建设用地供应在2013年出现拐点,供地结构逐步调整优化;土地利用效率显著提升,土地边际效益明显递减等.总结了耕地保护面临建设占用和生态保护双重压力、建设用地供应存在结构性错配和低效闲置等4方面问题.在此基础上,提出加强耕地保护和土地供给侧改革等5方面建议.     

TDI CCD相机动态成像对几何质量的影响研究

本文通过影像模拟的方法分析动态积分成像对空间TDI CCD相机成像几何质量的影响。首先对卫星固有推扫速度、像移速度与电荷转移速度失配、卫星三轴姿态运动及偏流角误差等4种动态成像因素进行了介绍,建立了4种因素的数学模型;在此基础上提出了空间TDI CCD相机成像模拟方法;最后提出统计单级静态影像和多级动态合成影像配准误差的分布特点评价与4种因素有关的内部几何质量,统计低阶多项式拟合的姿态曲线与实际姿态曲线条件下地面点像方误差的分布特点评价外部几何质量。     

BP神经网络遥感水深反演算法的改进

针对BP神经网络遥感水深反演算法（简称传统BP算法）的缺点,提出了改进型BP神经网络遥感水深反演算法（简称改进型BP算法）,其基本原理是在模型训练过程中反复运用粒子群算法对BP神经网络的权值和阈值进行优化以弥补传统BP算法的不足。试验表明：改进型BP算法的训练迭代收敛速度明显快于传统BP算法,浅水区的水深反演精度优于传统BP算法,且学习算法对初始权值和阈值不敏感。     

基于改进标记分水岭的高分辨率遥感影像海岸水边线提取方法

利用遥感技术快速提取海岸线是一种重要的技术手段,针对传统分水岭算法在高分辨率多光谱卫星数据处理中存在的过分割和抗干扰能力差的问题,本文提出了一种基于扩展极值变换标记分水岭的算法.首先通过形态学重建、扩展极值变换等方法建立前景和背景标记,初步抑制灰度极小值和极大值区域,然后依据这两类标记对梯度图像进行修正,进而进行分水岭...     

SOI和El Nino与湘潭汛期洪涝的关系

本文研究了湘潭汛期（4～9月）洪涝与南方涛动指数（SOI）和厄尔尼诺（ElNino）事件的遥相关联系。结果表明，南方涛动指数异常偏负（弱）以及厄尔尼诺事件的滞后影响对湘潭汛期洪涝的短期气候预报有很好的指示性。在统计分析的基础上，我们建立了日常业务应用的湘潭汛期洪涝预报物理模型。     

用因子场客观相似分析法制作湘潭汛期降水预报

为制作湘潭汛期降水量预报,对相拟方法作了改进,即将北半球500hPa环流场和北太平洋海温场作为基本背景场,然后用相关普查法寻找预报因子,组成一个预报因子场作相似分析,再做出客观定量预报,系统在计耳机上宴现,并对1994～1998年进行试报,其结果较好。     

旅游导向的乡村空间重构过程与机制——以南京市后圩村为例

乡村旅游是推动乡村空间重构的重要驱动力,探究其重构乡村空间的内在机制有利于完善乡村振兴的科学体系。本文以南京市后圩村为例,从“物质-关系-文化”三维视角剖析了旅游导向的乡村空间重构过程,并结合政府力、市场力、社会力互动作用逻辑分析其重构机制。研究结果表明：(1)后圩村物质空间重构以土地利用集中化和空间功能复合化为主要特征;关系空间重构呈现出空间主体多元化,关系网络复杂化,组织形式集中化,权属关系明晰化等特征;文化空间重构表现出空间内涵多样化和乡风文明规范化等特征。(2)政府力、市场力、社会力相互作用构成了驱动后圩村空间重构的核心动力,促进乡村“物质-关系-文化”空间的协同演进,共同推动乡村空间重构。乡村旅游发展不同阶段多元力量作用程度和方式存在显著差异。乡村旅游起步发展阶段社会力量主导空间重构,乡村旅游快速发展阶段多元力量合作博弈推动空间价值提升,乡村旅游转型升级阶段多元力量协同共治落实空间有序重构。旅游导向的乡村空间重构内在机制可为优化乡村振兴政策提供参考。     

丹东华能电厂主厂房震害预测

丹东华能电厂主厂房属高层建筑，结构型式复杂。本文采用现场测试与结构反应计算相结合的方法，计算了结构内力与楼层延伸率，最终给出了震害预测结果。     

黄淮海平原耕地功能演变的时空特征及其驱动机制（英文）

Using counties as the basic analysis unit,this study established an evaluation index system for farmland function(FF) from economic,social,and ecological perspectives.The method combining entropy weighting and multiple correlation coefficient weighting was adopted to determine the weights,and the FF indices were calculated for each county.Subsequently,the spatio-temporal characteristics of farmland function evolution(FFE) were analyzed and the coupled relationships between the sub-functions were explored based on a coupling coordination model.At the same time,the dynamic mechanism of FFE was quantitatively analyzed using a spatial econometric regression analysis method.The following major conclusions were drawn:(1) The farmland economic function generally exhibited a declining trend during 1990–2010,and it is essential to point out that it was stronger in underdeveloped and agriculture-dominated counties,while it continuously weakened in developed areas.Farmland social function decreased in 60.29% of the counties,whereas some counties,which were mostly located in north of Zhengzhou and west of Dezhou and Cangzhou,Yantai,and Weihai,clearly increased.A dramatic decline in farmland ecological function occurred around Beijing,Tianjin,and Jinan.Areas located in the northern part of Henan Province and the central part of Shandong Province saw an increase in ecological function.(2) There was a significant spatial difference in the coupling degree and coordination degree of the sub-functions,and the decoupling phenomenon highlighted this.The changes in social function and ecological function lagged behind economic function in developed areas,but these were highly coupled in some underdeveloped areas.(3) FFE in the Huang-Huai-Hai Plain(HHHP) is resulted from the comprehensive effects of regional basic conditions and external driving factors.Furthermore,the transitions of population and industry under urbanization and industrialization played a decisive role in the evolution intensity and direction of farmland sub-systems,including the economy,society,and the ecology.According to the results mentioned above,promoting the transformation from traditional agriculture to modern agricultureshould be regarded as an important engine driving sustainable development in the HHHP.Taking different regional characteristics of FFE into account,differentiated and diversified farmland use and management plans should be implemented from more developed urban areas to underdeveloped traditional agricultural areas.