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高新兵  李姗姗  李海  张宏伟  王应建 《大地测量与地球动力学》2013,33(1):145-149

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体感温度客观分析方法研究     

陈莉  张海东  王承伟  李帅 《成都信息工程学院学报》2009,24(3)

影响人体体感温度的气象要素主要包括温度、湿度、风以及太阳辐射,依据这些气象要素影响人体体感温度的原理,确定了平均气温与体感温度相同时的临界相对湿度、风速及太阳辐射值.以全国有水平面直接辐射曝辐量观测项目的77个气象台站的历年逐日4次定时观测资料为基础,把相邻两个白昼(夜间)的气温差作为因变量,相对湿度差、风速差、垂直辐射差(白昼)作为自变量,以旬为时问分辨率,建立了逐旬多元回归方程.各地所建立的逐句多元线性拟合方程拟合优度相当高,F统计量检验也充分证明线性回归方程总体成立,从气候意义、统计角度来看该方法都具有充分的可行性.  相似文献   

三维GIS的线性八叉树数据结构研究     

马智民  陈浩  王金玲 《地球科学与环境学报》1999,(Z1)

本文在分析和比较了三维ＧＩＳ中多种数据结构的基础上,重点讨论了线性八叉树编码原理、线性八叉树数据结构以及线性八叉树的生成、显示与操作,并从数据结构的优缺点着眼,提出将ＢＲ 法与线性八叉树相结合的观点;从三维动画技术着眼,提出将原型法、ＣＳＧ 法与线性八叉树相结合的观点,最后提出一种基于多元表示的三维ＧＩＳ系统的构想框架  相似文献   

Eemian and Early Weichselian environments in southern Sweden: a multi‐proxy study of till‐covered organic deposits from the Småland peneplain     

GEOFFREY LEMDAHL  ANNA BROSTRÖM  LARS HEDENÄS  KRISTINA ARVIDSSON  SOFIA HOLMGREN  MARIE‐JOSÉ GAILLARD  PER MÖLLER 《第四纪科学杂志》2013,28(7):705-719

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North Atlantic climate impact on early late‐glacial climate oscillations in the south‐eastern Alps inferred from a multi‐proxy lake sediment record     

Roland Schmidt  Kaarina Weckström  Stefan Lauterbach  Richard Tessadri  Kerstin Huber 《第四纪科学杂志》2012,27(1):40-50

High‐resolution multi‐proxy analyses of a sediment core section from Lake Jeserzersee (Saissersee) in the piedmont lobe of the Würmian Drau glacier (Carinthia, Austria) reveal pronounced climatic oscillations during the early late glacial (ca. 18.5–16.0k cal a BP). Diatom‐inferred epilimnetic summer water temperatures show a close correspondence with temperature reconstructions from the adjacent Lake Längsee record and, on a hemispheric scale, with fluctuations of ice‐rafted debris in the North Atlantic. This suggests that North Atlantic climate triggered summer climate variability in the Alps during the early late glacial. The expansion of pine (mainly dwarf pine) between ca. 18.5 and 18.1k cal a BP indicates warming during the so‐called ‘Längsee oscillation’. The subsequent stepwise climate deterioration between ca. 18.1 and 17.6k cal a BP culminated in a tripartite cold period between ca. 17.6 and 16.9k cal a BP with diatom‐inferred summer water temperatures 8.5–10 °C below modern values and a shift from wet to dry conditions. This period probably coincides with a major Alpine glacier advance termed the Gschnitz stadial. A warmer interval between ca. 16.9 and 16.4k cal a BP separates this cold phase from a second, shorter and less pronounced cold phase between ca. 16.4 and 16.0k cal a BP, which is thought to correlate with the Clavadel/Senders glacier advance in the Alps. The following temperature increase, coupled with wet (probably snow‐rich) conditions, caused the expansion of birch during the transition period to the late glacial interstadial. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

皖江中东部雾的客观预报自动化业务系统     

周述学  叶金印 《气象》1994,20(11):37-39

介绍了一种雾的客观预报方法，并研制了一个与ＳＴＹＳ接口的雾的客观预报自动化业务系统，对雾有一定的预报能力。  相似文献   

地球物理非线性反演模拟退火法的改进   总被引：33，自引：9，他引：33       下载免费PDF全文

姚姚 《地球物理学报》1995,38(5):643-650

在地球物理非线性反演方法中，模拟退火法是一种较先进的启发式蒙特卡洛（ＭｏｎｔｅＣａｒｌｏ）方法．但是，在处理实际资料时，该方法存在着计算效率不够高的缺点，有时还会失效．为此，从模拟退少法的关键问题──最低温度的选择入手，根据模拟退火法与统计力学的吉布斯－马尔柯夫（Ｇｉｂｂｓ－Ｍａｒｋｏｖ）模型之间的关系导出临界温度的近似表达式；用此式分析目标函数超曲面形状对模拟退火法计算的影响；提出利用模糊先验信息确定最低温度、改造目标函数等改进措施．  相似文献   

Identification of modal parameters of non‐classically damped linear structures under multi‐component earthquake loading     

M. Mahmoudabadi  M. Ghafory‐Ashtiany  M. Hosseini 《地震工程与结构动力学》2007,36(6):765-782

A method for parametric system identification of classically damped linear system in frequency domain is adopted and extended for non‐classically damped linear systems subjected up to six components of earthquake ground motions. This method is able to work in multi‐input/multi‐output (MIMO) case. The response of a two‐degree‐of‐freedom model with non‐classical damping, excited by one‐component earthquake ground motion, is simulated and used to verify the proposed system identification method in the single‐input/multi‐output case. Also, the records of a 10 storey real building during the Northridge earthquake is used to verify the proposed system identification method in the MIMO case. In this case, at first, a single‐input/multi‐output assumption is considered for the system and modal parameters are identified, then other components of earthquake ground motions are added, respectively, and the modal parameters are identified again. This procedure is repeated until all four components of earthquake ground motions which are measured at the base level of the building are included in the identification process. The results of identification of real building show that consideration of non‐classical damping and inclusion of the multi‐components effect of earthquake ground motions can improve the least‐squares match between the finite Fourier transforms of recorded and calculated acceleration responses. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

空间信息可视化的现状与趋势   总被引：10，自引：0，他引：10  

刘纪平  常燕卿等 《测绘学院学报》2002,19(3):207-210

对空间信息可视化的现状进行了较为细致的总结，分析了目前空间信息可视化存在的问题。在此基础上，讨论了空间信息可视化的完整概念，提出了空间信息可视化位置特征、交互性、多维性和可视化多样性的本质特征，概括了数据组织与调度、静态可视化、过程模拟与探索性分析等空间信息可视化基本过程。最后，提出未来空间信息可视化主要关键技术。  相似文献   

福建省物探找矿若干实例分析   总被引：1，自引：0，他引：1  

黄海清  许井明  黄春鹏 《福建地质》2002,21(1):27-34

物探作为一种地质勘察技术方法在国民经济各个领域，得到广泛的应用，物探方法和其它地质学科一样都存在着不足为奇的解释多解性。通过对福建省金，多金属，煤等矿产的地球物理勘察实例分析。认为要取得物探找矿效果应注意以下几点；（1）分析矿产的地质规律和特点；（2）掌握矿体与围岩之间物性差异的特征，直接找矿与间接找矿并举；（3）选择适合的物探方法，发挥各种方法的长处，（4）建立和利用矿床的地质-地球物理模型。圈出矿床（体）赋存的部位。  相似文献