Analyse statistique de directions non orientees

Résumé On propose un mode de calcul des directions principales d'un ensemble de directions non orientées et des tests de précision. On propose des applications à l'analyse de nuages de pôles et à la recherche d'intersection de cercles de réaimantation.

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Statistical analysis of non-orientated directions. A computing mode of principal directions of a set of non-orientated directions or lineations and statistical tests are presented. An application to the analysis of a set of poles and for finding the intersection of remagnetisation circles is shown.

     

利用瑞利激光雷达和无线电探空仪观测数据对武汉上空重力波特性的研究

本文利用武汉大学的瑞利激光雷达的瑞利散射回波数据(30～65km)来研究武汉地区上空(30.5°N,114.4°E)重力波的活动规律和统计特性.通过对2003年12月到2005年3月观测的200h数据反演的密度进行处理分析,得到了重力波的一些个例特征,并提取垂直波长为2 km以上的重力波进行统计分析.结果表明,最可几的垂直波长是3～4 km和17～20 km,重力波振幅的月平均值在冬季有较大值,夏季值较小.与武汉2004年无线电探空仪的密度扰动提取到的重力波做比较,发现与瑞利激光雷达得到的重力波振幅的月平均值有很强的相关性,也是冬季值比较大,夏季值比较小.通过无线电探空仪的风场数据,本文还得到了急流的季节变化规律、最大风剪切年变化规律,发现急流和最大风剪切与激光雷达的重力波统计结果有很强的相关性.     

河南省气象部门科技服务与产业统计报表处理系统

根据统计工作需要，设计和开发了河南省气象部门科技服务与产业统计报表处理系统。该系统集成了报表处理过程中所需要的各种功能，界面友好，操作简单。     

How significant (p < 0.05) is geomorphic research?

The pervasive application of the Null Hypothesis Significance Test in geomorphic research runs counter to widespread, long running, and often severe criticism of the method in the broader scientific literature. The application of the methodology typically leads to a binary separation of evidence into ‘significant’ and ‘not significant’ results based on a p‐value that is dependent on the null hypothesis being true. The method should not therefore be used to provide statistical support for substantive hypotheses, and is unsuitable for scientific inference in open systems where confirmation can only ever be partial. Alternative approaches based on Bayesian statistics can importantly be applied to measure partial support for hypotheses, conditional on the available data. Though not without their own assumptions, wider application of such methods can help facilitate a transition towards a broader approach to statistical, and in turn, scientific inference in geomorphic systems. Copyright © 2014 John Wiley & Sons, Ltd.     

3D DEMAP数值模拟与观测实验

为推动电磁剖面(EMAP)技术向找矿勘探领域发展,本文针对密集阵列剖面(DEMAP)测量方式,利用三维积分方程法对层状介质中赋存三维地质异常体的电性结构进行了数值模拟,并在青海野马泉铁锌矿集区西部进行了大地电磁(MT)与DEMAP的野外对比观测实验.数值模拟结果显示,DEMAP观测方式获得的结果受偏移距影响,造成的视电阻率和相位误差与偏移距大小和地下电性结构的复杂性密切相关,但在整体上,统计误差≤10%.通过对野马泉矿集区的实验结果分析可得,DEMAP与MT的视电阻率断面和相位断面具有较好的一致性.本文从理论和实验上都表明DEMAP观测技术是一种有潜力的、经济、快速、有效的找矿手段.     

A dependence modelling study of extreme rainfall in Madeira Island

The dependence between variables plays a central role in multivariate extremes. In this paper, spatial dependence of Madeira Island's rainfall data is addressed within an extreme value copula approach through an analysis of maximum annual data. The impact of altitude, slope orientation, distance between rain gauge stations and distance from the stations to the sea are investigated for two different periods of time. The results obtained highlight the influence of the island's complex topography on the spatial distribution of extreme rainfall in Madeira Island.     

Flood Fatalities in Australia, 1788-1996

Information on fatalities from flooding in Australia has been compiled from newspapers, historical accounts, and government and scientific reports. Records covering 1788 to 1996 indicate that at least 2213 persons have been killed in floods in Australia. The overall decadal death rate has decreased from 23.98 per 100 000 population in the 1800s to 0.04 per 100 000 in the 1990s. The greatest number of fatalities has occurred in New South Wales but, taking population into account, Queensland has been the most vulnerable state historically as, more recently, has been the Northern Territory. Most fatalities have occurred during February, and amongst males (80.6 per cent). The overall male:female death and death-rate ratios are both 4:1. Whereas the male:female death-rate ratio has fluctuated over time from 10:1 to 1:1, it does not approach equality. Most fatalities (38.5 per cent) have occurred through attempts to cross creeks, bridges or roads in times of flood. Another 31.5 per cent of victims were in houses-the majority awaiting rescue, or simply unaware of the flood. Of the total known deaths, work-related fatalities have accounted for 12.4 per cent, and recreational pursuits for 5.7 per cent.     

紫坪铺库区断层分布规律统计分析

定量描述地质构造的分布规律对诸如核废料地质处置、边坡稳定性分析、采矿工程以及水利水电工程都具有十分重要的意义。本文根据紫坪铺水库工程区域地质图,通过提取断层信息的方法,获得了断层分布图。对紫坪铺水利枢纽工程库区内尺度跨越3个数量级、共126条断层进行了统计分析,获得了断层长度-数量间的幂律关系,即N(r)~r-D。并通过分段线性拟合的方法,计算了幂指数的值。发现当断层长度r2.5km时,幂指数D=0.32;而当断层长度r2.5km时,幂指数D=1.58。该幂律关系对推演更小或更大规模断层分布具有重要意义。     

Ground settlement monitoring based on temporarily coherent points between two SAR acquisitions

An InSAR analysis approach for identifying and extracting the temporarily coherent points (TCP) that exist between two SAR acquisitions and for determining motions of the TCP is presented for applications such as ground settlement monitoring. TCP are identified based on the spatial characteristics of the range and azimuth offsets of coherent radar scatterers. A method for coregistering TCP based on the offsets of TCP is given to reduce the coregistration errors at TCP. An improved phase unwrapping method based on the minimum cost flow (MCF) algorithm and local Delaunay triangulation is also proposed for sparse TCP data. The proposed algorithms are validated using a test site in Hong Kong. The test results show that the algorithms work satisfactorily for various ground features.     

延庆盆地地下水水化学特征统计分析

基于2008年枯水期地下水采样数据共计65个样本点,对水质组分进行了分层统计,并进行了地下水质量评价。此外,开展了TDS、Ca2＋、NO3-和硬度与取样深度的相关性分析。结果表明,垂向上,延庆盆地地下水由浅到深,地下水水质逐渐变好;横向上,上游地下水水质好于中游,中游好于下游;深层地下水已经出现较差和极差点。