Research on the fuzzy relationship between the precursory anomalous elements and earthquake elements

IntroductionThepreparationandoccurrenceofearthquakesareofthecomplicatednaturewithsomephysicalorchemicalphenomena,socalledasearthquakeprecursorswhichmightbeexpectedtobeusedtopredictearthquake,speciallystrongearthquake.Intheresearchofearthquakeprediction,however,theproblemthathowtheprecursorscouldbeidentifiedtoattributetoanearthquakehasbeenstillunsolved.AsthefirststeptheresearchoftherelationbetWeentheprecursoryinformatiollandearthquakeelements(magnitude,space,andoccurrencetime)needtobeconducted.…     

多级模糊评判方法在地震预报中的某些应用

本在前人工作的基础上,把多级模糊评判方法应用到地震综合预报工作中。选取地震活动性和定点前兆共１４个因子作为因素集合,建立综合评判矩阵和综合预报地震强度的评判模型,并应用于天津及邻近地区地震预报中。结果证明多级模糊评判方法在综合预报中有一定的应用前景。     

A pseudo-Thellier relative palaeointensity record, and rock magnetic and geochemical parameters in relation to climate during the last 276 kyr in the Azores region

In the pseudo-Thellier method for relative palaeointensity determinations (Tauxe et al. 1995) the slope of the NRM intensity left after AF demagnetization versus ARM intensity gained at the same peak field is used as a palaeointensity measure. We tested this method on a marine core from the Azores, spanning the last 276  kyr. We compared the pseudo-Thellier palaeointensity record with the conventional record obtained earlier by Lehman et al . (1996 ), who normalized NRM by SIRM. The two records show similar features: intensity lows with deviating palaeomagnetic directions at 40–45  ka and at 180–190  ka. The first interval is associated with the Laschamps excursion, while the 180–190  ka low represents the Iceland Basin excursion (Channell et al. 1997). The pseudo-Thellier method, in combination with a jackknife resampling scheme, provides error estimates on the palaeointensity.
  Spectral analysis of the rock magnetic parameters and the palaeointensity estimates shows orbitally forced periods, particularly 23  kyr for climatic precession. This suggests that palaeointensity is still slightly contaminated by climate. Fuzzy c -means cluster analysis of rock magnetic and geochemical parameters yields a seven-cluster model of predominantly calcareous clusters and detrital clusters. The clusters show a strong correlation with climate, for example samples from detrital clusters predominantly appear during rapid warming. Although both the pseudo-Thellier palaeointensity m _a and fuzzy clusters show climatic influences, we have not been able to find an unambiguous connection between the clusters and m _a .     

Fuzzy Weights of Evidence Method and Its Application in Mineral Potential Mapping

This paper proposes a new approach of weights of evidence method based on fuzzy sets and fuzzy probabilities for mineral potential mapping. It can be considered as a generalization of the ordinary weights of evidence method, which is based on binary or ternary patterns of evidence and has been used in conjunction with geographic information systems for mineral potential mapping during the past few years. In the newly proposed method, instead of separating evidence into binary or ternary form, fuzzy sets containing more subjective genetic elements are created; fuzzy probabilities are defined to construct a model for calculating the posterior probability of a unit area containing mineral deposits on the basis of the fuzzy evidence for the unit area. The method can be treated as a hybrid method, which allows objective or subjective definition of a fuzzy membership function of evidence augmented by objective definition of fuzzy or conditional probabilities. Posterior probabilities calculated by this method would depend on existing data in a totally data-driven approach method, but depend partly on expert's knowledge when the hybrid method is used. A case study for demonstration purposes consists of application of the method to gold deposits in Meguma Terrane, Nova Scotia, Canada.     

渤海湾盆地第三纪的岩浆旋回

本文提出了岩浆旋回的概念,初步探索了岩浆旋回的划分方法,并以构造演化为基础,结合岩浆活动方式、岩石地球化学指标,对渤海湾盆地岩浆旋回进行了划分。盆地中第三纪岩浆活动划分为两大旋回：早第三纪华北Ⅰ幕旋回和晚第三纪华北Ⅱ幕旋回。第一旋回（华北Ⅰ幕）划分为3期：孔店组（房身泡组）—沙河街组四段期、沙河街组三段—沙河街组二段期及沙河街组一段—东营组期。第二旋回（华北Ⅱ幕）为晚第三纪。旋回内部各期的早、晚岩浆活动形式有所不同。     

神经智能信息处理系统的研究现状及其在水文水资源中的应用展望

从神经网络(NN),模糊系统(FS)和进化算法(EC)三者相结合的角度,介绍了神经智能信息处理系统的研究现状,讨论了该系统在水文水资源中的应用,并对其应用发展趋势进行了预测。     

模糊综合评判法在水质评价中的应用及探讨

指出了以往水质模糊综合评判法中权重确定方法和评价结果表达形式的不合理之处,并提出了改进后的权重确定方法和结果表达形式来解决这些问题,使模糊综合评判法更加合理和实用,并用实例进行了验证.     

日本海沟大震与华东地区地震的相关性

应用模糊相关方法,研究了日本海沟与我国华东地区地震活动的相关性.计算结果表明:日本海沟地区(35～45°N,140～150°E)MS6.8级以上地震和华东地区(29～34°N,119～124°E)MS4.8级以上地震有较好的相关对应关系;用相关分析方法对华东地区尤其是上海附近地区未来发震的可能性进行了分析,并估算了两地区延迟相关的平均概率.     

多目标模糊优选模型在环境质量评价中的应用

环境质量评价属于多因子识别和排序问题。在实际应用中评价因子的基准往往难以确定 ,从而影响评价结果。针对此问题 ,提出了多目标模糊优选模型 ,它是分析多目标环境系统的一个较新的方法 ,在介绍该理论的基础上 ,建立了环境质量评价模型 ,并在吉林西部进行了应用 ,通过与其它评价方法的比较表明 ,该方法用于环境质量评价具有通用性、合理性和实用性     

基于模糊数学的广东沿海陆地地质环境区划

针对广东沿海地震、水土流失、崩塌、滑坡、地裂缝、地面沉降、岩溶塌陷、软土地基形变等地质灾害发育历史与现状 ,从土地开发利用的风险与费用出发 ,构建了一套地质环境评价的指标体系 ,包括活动断裂、历史地震、地形起伏度、地形坡度、沟谷密度、水土流失程度、崩滑密度、地裂缝密度、土体承载力等。通过指标量化分级、指标赋权和构造隶属函数 ,构建了模糊数学综合评价模型 ,对广东沿海 190单元进行了运算 ,将广东沿海陆地地质环境划分五级 17个亚区 ,为广东沿海2 1世纪土地开发利用和防灾减灾等提供了决策依据。