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101.
本文论述作者对不连续植被冠层与辐射间相互作用机理研究的最新进展,提出了建立不连续植被二向性反射分布函数的几何光学与辐射传输一体化综合模型的设想和基本理论。该综合模型的建立以Li-Strahler间隙概率模型为基础,在大尺度上用纯几何光学模型反映植被的结构特征,在适于辐射传输模型的尺度上则以冠层内的间隙概率处理叶丛的截获辐射与散射。本文详细说明了冠层内任意高度的间隙率模型,也介绍了多次散射的建模方法。 相似文献
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<正>People'sRepublicofChinaisoneofthemostrapidlydevelopingcountriesintheworldtoday.Thereisagreatdemandonhighlyactualandaccuratespatialinformationofthewholecountry,especiallyofWestChinawhichbecomesthefocusofdevelopmentoftheChinesegovernmentrightnowandinthenextyears,butwherestillnotenoughtopographicmapsareavailable.ThisraisesgreatchallengestothesurveyingandmappingcommunityinChina.FacingthenewchallengestheChineseAcademyofSurveyingandMapping(CASM)starteditspioneerworkearly2002toexplorenewtechniquesandtechnologiesavailabletodaytowardincreasingthemapproductivity.WithimportofaCCNS/AEROcontrolsysteminNovember2002,thefirstDGPS/IMU-basedphotogrammetricprojectinChinawassuccessfullyaccomplishedjointlybyCASM,theGermany-basedcompaniesIGIandTechedge.Twophotogrammetricblocksof1:4,000and1:20,000photoscales,respectively,wereflowninAnyang,China.Directgeoreferencingandintegratedsensororientationwereconducted.Resultsachievedwereprovenbyusinggroundcheckpointsandcomparedwiththoseofaerialtriangulation.Orthophotosgeneratedbasedondir 相似文献
104.
利用S波纯波形拟合法以及T函数法反演了苏鲁地区壳幔剪切波速度结构,并利用长周期P波T函数反演得到了连云港和莱阳台下方800km深度的速度结构。结果显示:(1)苏鲁地区大部分台站地壳表层及上地壳浅部速度偏高,分别对应高压、超高压物质和古老基底出露地区;(2)沿郯庐断裂带分布的台站均显示明显低速层,并具有北浅南深的特点;(3)连云港和莱阳台超深度反演结果显示两台均在150km深度下出现高速层,反映扬子板块的俯冲深度为100km以下,俯冲板片厚度在100km以上;板片拆离下沉深度甚至达到300km或者更深;(4)地震深度分布与低速层关系密切,沿郯庐断裂和烟台—五莲断裂的中小地震震源深度都比较深,有的甚至达到地壳的底部,反映这两条断裂目前切割深度都比较大,而且地幔物质相对比较活跃。 相似文献
105.
Constructing quality: The multinational histories of chocolate 总被引:1,自引:0,他引:1
Geographic research on food quality, while considering many of the ways in which quality is socially constructed, has largely focused on the place-based aspects of the raw materials of food production. Here, we use French convention theory to look at a highly processed food in order to show how place associations in the social construction of food quality extend to manufacturing. For chocolate, quality is based on material characteristics whose relative importance in determining quality depends on the country in which different stages of economic innovation took place. Struggles over the definition of quality chocolate, as exemplified by the “European Chocolate War,” show how quality issues are connected to geographies of manufacturing and innovation. 相似文献
106.
In the absence of strong motion records, ground motion during the 26th January, 2001 Kutch, India earthquake, has been estimated by analytical methods. A contour map of peak ground acceleration
(PGA) values in the near source region is provided. These results are validated by comparing them with spectral response recorder
data and field observations. It is found that very near the epicenter, PGA would have exceeded 0.6 g. A set of three aftershock
records have been used as empirical Green's functions to simulate ground acceleration time history and 5% damped response
spectrum at Bhuj City. It is found that at Bhuj, PGA would have been 0.31 g–0.37 g. It is demonstrated that source mechanism
models can be effectively used to understand spatial variability of large-scale ground movements near urban areas due to the
rupture of active faults. 相似文献
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108.
根据察尔汗盐湖别勒滩卤水等温蒸发试验数据,结合大量生产取样分析资料,对盐田光卤石矿生产机理及其控制因素作了分析研究,并提出了管理措施。 相似文献
109.
Synthesis of available data allows us to define general patterns of late Quaternary carbonate production and sedimentation
in the global ocean. During high stands of sea level, the neritic and pelagic environments appear to sequester approximately
similar amounts of carbonate, whereas during low stands of sea level the decreased neritic zone produces and accumulates approximately
an order of magnitude less carbonate. Assuming that global accumulation of deep-sea carbonates remains more or less constant
during glacially induced changes in sea level, the ocean becomes depleted with respect to calcium carbonate during high stands
and recharges during low stands. Before we can achieve a better understanding of the global carbonate system, however, we
need a better understanding of key environments and processes: (a) production and accumulation on continental shelves both
as potential sinks (accumulation) and as sources (export to the deep sea); (b) a better measure of pelagic carbonate production;
and (c) late Quaternary (late Pleistocene and Holocene) mass accumulation rates in the deep sea. 相似文献
110.