多级模糊综合评判在油气资源评价中的应用

基于模糊综合评判理论，建立了一级评判、多级评判的模型，讨论了模糊评判的反问题及其应用，用VC^ 5.0语言在Windows95/98平台上开发了相应的程序，给出了一级评判和多级评判模型在储层评价方面的应用实例，结果表明，多级模糊综合评判不但比传统的判别分析更符合客观实际，同时，通过反问题的求解，可重构相应的因素集和评价集，有助于成因机理预测。     

整数群上一类和超差集合的构造

考虑了整数群子集自身和及自身差势的问题，基于对前人给出的几类整数群上超差集合构造的研究，通过对典型有限和超差集合A。的有限分解，即A1={0，2}U{3，7，11，…，4k-1}U{4k，4k＋2}U{4}，其中k是不小于3的正整数，证明给出了整数群上一类无限的和超差集合的构造，使集合的势从有限上升为无限，拓展了前人的理论成果。     

Geologically Constrained Fuzzy Mapping of Gold Mineralization Potential,Baguio District,Philippines

An application of the theory of fuzzy sets to the mapping of gold mineralization potential in the Baguio gold mining district of the Philippines is described. Proximity to geological features is translated into fuzzy membership functions based upon qualitative and quantitative knowledge of spatial associations between known gold occurrences and geological features in the area. Fuzzy sets of favorable distances to geological features and favorable lithologic formations are combined using fuzzy logic as the inference engine. The data capture, map operations, and spatial data analyses are carried out using a geographic information system. The fuzzy predictive maps delineate at least 68% of the known gold occurrences that are used to generate the model. The fuzzy predictive maps delineate at least 76% of the unknown gold occurrences that are not used to generate the model. The results are highly comparable with the results of previous stream-sediment geochemical survey in the area. The results demonstrate the usefulness of a geologically constrained fuzzy set approach to map mineral potential and to redirect surficial exploration work in the search for yet undiscovered gold mineralization in the mining district. The method described is applicable to other mining districts elsewhere.     

基于灰集的不确定性时空数据模型

不确定性处理是时空数据库面临的新问题。其研究的首要任务是对不确定时空对象进行建模,研究时空不确定性的表示和存储,进而设计离散模型实现数据库系统。提出了建立在灰集理论上的时空数据抽象模型,适合处理部分已知部分未知的不确定对象。首先给出了抽象数据类型的定义,包括建立在灰集理论上的基本数据类型,空间数据类型和时空数据类型;随后对不确定时空分析操作进行了简单的定性分析;最后给出不确定性时空查询的表达方式。     

利用粗集理论的声呐图像边缘锐化

边缘锐化是图像增强的重要内容。声呐图像像素少品质恶劣,边缘锐化是个难题。粗集理论是一种新的处理含糊和不确定性问题的数学工具,它为智能信息处理提供了有效的处理技术。将粗集理论应用于声呐图像的边缘锐化中,给出了实验结果。结果表明这种方法具有可行性。     

一种随机粗糙海面电磁散射的极化核函数

从磁场的积分方程出发,应用迭代方法推导了二次迭代条件下粗糙海面的近似电磁散射极化核函数,并对其进行了分析.这种函数的表示是在光学近似即KA近似的基础上的一种扩展形式,因而可称为扩展KA近似(EKA).Elfouhaily采用了与Holliday类似的方法分析了双站配置条件下散射的极化核函数,试图保留所有的高次项,但是由于处理的复杂性他只给出了斜率项在散射项中的表示形式,并称之为KA近似的“补充项”.本文在此基础上进一步考虑了Elfouhaily近似的形式,给出了表示双站散射极化核函数的完整表达形式,并以此为基础推算了后向散射条件下极化核函数的理论结果,并与Elfouhaily的结果进行了对比,说明了极化核函数完整表达形式的合理性.近似散射极化核函数的分析对于深入理解粗糙表面(特别是海面)电磁散射特性以及散射近似模型的建立等问题的研究具有重要意义.     

太原雷暴大风潜势预报方法研究

利用太原市7个国家观测站实况、探空以及MICAPS等资料,对1998—2018年5—9月太原的雷暴大风进行天气学分型,选取雷暴大风的消空因子以及不同天气型下的预报因子并确定其阈值,利用指标叠套法,建立雷暴大风潜势预报方法,并进行预报检验。结果表明：(1)选取700 hPa温度露点差、850 hPa与500 hPa的温差、条件性稳定度指数和混合相层4个环境参数作为消空因子并确定了消空阈值。（2）将雷暴大风分为高空槽型、冷涡型、切变线型、西北气流型和副高边缘型5类,选取了5类天气型下雷暴大风的预报因子,利用指标叠套法,建立了太原雷暴大风潜势预报方法。(3)运用雷暴大风潜势预报方法开展历史样本回报检验和2019-2020年试预报检验,取得了较好的预报效果。     

The fractal geometry of the soil—covered landscape

The soil-covered landscape surface can be idealized from two viewpoints. The intuitive view is of a smooth, absolutely continuous surface with continuous contour lines and measurable in integral dimensions. The alternative view emphasizes the roughness, a surface of little regularity and at the limit of no contours, the appropriate measure being that of fractional Hausdorff dimension. Regularity is a local property and both idealizations need to stop far short of the limit to avoid awkward consequences. The dichotomy of viewpoint can be matched in the theory of Gaussian random fields. These, if they are smooth, are very smooth but if they are irregular they are highly irregular (erratic); there is no middle ground. This Belayev dichotomy is defined and both modes applied to the soil-covered landscape. On the one hand, if the landscape is subject to a general diffusive type degradation or more generally a Davisian downwasting regime then the curvature of the landscape surface is progressively straightened and the distribution of gradient (increments) along a typical traverse will eventually adopt a Gaussian form. Then from the irregular viewpoint the surface is ultimately well represented by a fractional Brownian surface of low Hausdorff dimension (2·0 < dim < 2·3). The Hausdorff dimension is directly related to the entropy of the landscape and as degradation proceeds both quantities decrease in value. On the other hand, if the surface is regarded as smooth and well represented by an absolutely continuous Gaussian field then the mean value of the number of upcrossings of a level or the extent of an excursion set will also be Gaussian. This analysis is restricted to one dimension; the number of times a profile curve crosses or the amount of time it spends above any given level. Predictions from both viewpoints are substantially corroborated in a map analysis of 15 sites on varied terrains in Southern England and the map analysis checked against one based upon digital tape data for one of the sites.     

Compositional Kriging: A Spatial Interpolation Method for Compositional Data

Compositional data are very common in the earth sciences. Nevertheless, little attention has been paid to the spatial interpolation of these data sets. Most interpolators do not necessarily satisfy the constant sum and nonnegativity constraints of compositional data, nor take spatial structure into account. Therefore, compositional kriging is introduced as a straightforward extension of ordinary kriging that complies with these constraints. In two case studies, the performance of compositional kriging is compared with that of the additive logratio-transform. In the first case study, compositional kriging yielded significantly more accurate predictions than the additive logratio-transform, while in the second case study the performances were comparable.     

基于Rough集理论的矿井突水规则获取

以突水样例的一个子集为例,采用可变精度的Rough集模型,经过对原始决策信息表的数据预处理、属性约简、值约简和规则生成等主要步骤,最终获得了与该样例子集相适应的若干突水规则,这些规则较好地覆盖了该样例子集所包含的突水信息,具有同等的分类决策效果。