Theory and Practice in Mathematical Geology—Introduction and Discussion     

Hannes Thierg?rtner 《Mathematical Geology》2006,38(6):659-665

Mathematical geology has developed into a very diverse system of mathematical models, algorithms and corresponding software. Experience shows that this diversification of approaches and methods was and is accompanied by an increasing gap between the availability of powerful tools and the continuation of many traditional working methods in the geosciences. Besides continuing to develop models, one of the basic functions of mathematical geology should be to introduce all new tools into practice and to aid non-specialized geoscientists to use them successfully and without bias. Some ways to do so will be briefly discussed here. Instructive and intelligible contributions towards attaining this goal were presented at the last (32nd) International Geological Congress held in Florence, Italy, in 2004. The intention of this present compilation is to suggest relevant discussions and conclusions. Mathematical geology should not be the domain of a few experts. It should be made accessible to all geologists and scientists in related fields.  相似文献   

A comparative study of conventional, ANN black box, fuzzy and combined neural and fuzzy weighting procedures for landslide susceptibility zonation in Darjeeling Himalayas   总被引：7，自引：0，他引：7  

D.P. Kanungo  M.K. Arora  S. Sarkar  R.P. Gupta   《Engineering Geology》2006,85(3-4):347-366

Landslides are one of the most destructive phenomena of nature that cause damage to both property and life every year, and therefore, landslide susceptibility zonation (LSZ) is necessary for planning future developmental activities. In this paper, apart from conventional weighting system, objective weight assignment procedures based on techniques such as artificial neural network (ANN), fuzzy set theory and combined neural and fuzzy set theory have been assessed for preparation of LSZ maps in a part of the Darjeeling Himalayas. Relevant thematic layers pertaining to the causative factors have been generated using remote sensing data, field surveys and Geographic Information System (GIS) tools. In conventional weighting system, weights and ratings to the causative factors and their categories are assigned based on the experience and knowledge of experts about the subject and the study area to prepare the LSZ map (designated here as Map I). In the context of objective weight assignments, initially the ANN as the black box approach has been used to directly produce an LSZ map (Map II). In this approach, however, the weights assigned are hidden to the analyst. Next, the fuzzy set theory has then been implemented to determine the membership values for each category of the thematic layer using the cosine amplitude method (similarity method). These memberships are used as ratings for each category of the thematic layer. Assuming weights of each thematic layer as one (or constant), these ratings of the categories are used for the generation of another LSZ map (Map III). Subsequently, a novel weight assignment procedure based on ANN is implemented to assign the weights to each thematic layer objectively. Finally, weights of each thematic layer are combined with fuzzy set derived ratings to produce another LSZ map (Map IV). The maps I–IV have been evaluated statistically based on field data of existing landslides. Amongst all the procedures, the LSZ map based on combined neural and fuzzy weighting (i.e., Map IV) has been found to be significantly better than others, as in this case only 2.3% of the total area is found to be categorized as very high susceptibility zone and contains 30.1% of the existing landslide area.  相似文献   

模糊聚类实现岩性自动划分     

徐海波  李瑞  邹炜  潘杨辉 《物探化探计算技术》2006,28(4):319-321

利用测井数据中的自然伽玛、中子、声波和密度测井曲线所蕴含的岩性信息,用模糊聚类算法实现岩性的自动划分。该方法识别准确度高,可靠性强。通过对川西坳陷十八口井的实际应用,此方法在低孔低渗的致密碎屑岩岩性划分中取得了良好的效果。  相似文献   

模糊综合评价法在地下水水质评价中的应用   总被引：13，自引：1，他引：13  

李进  陈益滨  师伟  梁煦枫 《地下水》2006,28(2):4-5,22

将模糊数学应用于水质评价中.模糊综合评价法通过建立和确定因子集、评价集、隶属函数和权重集等模糊集合,进行环境评价.选择咸阳市地表水环境质量对模糊综合评价法进行验证.评价结果符合实际情况.说明模糊综合评价法可用于环境质量综合评价.  相似文献   

杭州市水资源开发利用阈限分析的综合评价     

佘孝云  汤洁  赵芝清 《世界地质》2006,25(2):177-181,186

基于模糊数学理论的区域水资源开发利用阈限分析方法,选取灌溉率、产水系数、水资源开发程度、供需水模数、人均供水量和生态用水率7个主要因素作为评价因素,以杭州市区为例进行具体计算与分析。评判结果表明,杭州市区水资源开发已经达到相当的规模,在水资源开发过程中,处于过渡阶段。  相似文献   

灌区运行状况综合评价的方法研究   总被引：20，自引：0，他引：20       下载免费PDF全文

李慧伶  王修贵  崔远来  李凯  方彬 《水科学进展》2006,17(4):543-548

研究了使用模糊综合评价和灰色系统评价对灌区的运行状况进行综合评价的方法。在确定权重时,运用了博弈论方法将主观赋权法(层次分析法)和客观赋权法(熵值法)进行集化、融合,使得到的综合权重与各单一权重向量之间的偏差最小,该法消除了单一权重法的片面性,操作简便,便于实际应用。以山东省部分灌区为例,运用上述方法对其进行综合排序,结果表明,其排序结果基本一致,说明将这两种方法运用到灌区综合评价中是切实可行的。  相似文献   

模糊地理实体的表示及其性质的研究     

胡圣武  王宏涛 《测绘与空间地理信息》2006,29(2):8-10

对模糊地理实体的点实体、线实体和面实体的模糊性进行了研究,就它们的模糊表示进行了阐述。特别是就模糊面实体和确定的面实体进行对比,就二者的不同点进行了探讨,并给出了模糊面实体的实例,最后对本文进行了总结,得出了本文的研究只是一个探讨,还有很多问题需要解决。  相似文献   

旅游城市可持续发展评价指标体系   总被引：6，自引：2，他引：6  

戴永光 《云南地理环境研究》2006,18(1):35-38,42

旅游业正在世界范围内蓬勃兴起，但随之而来也引起了旅游城市的一系列问题，如何评价旅游城市的可持续发展就显得很有必要。依据旅游城市可持续发展的特殊性，确定了其指标体系构建的基本原则，应用模糊评价方法计算得到具有代表性的34个评价因子，试着初步构建旅游城市可持续发展指标体系，并对指标体系的层次架构、指标的涵义作了具体说明，也对指标体系评价应用过程作了简要介绍。  相似文献   

城乡一体化过程中农民满意度调查研究     

任平  周介铭  何伟  蒋贵国 《云南地理环境研究》2006,18(1):75-78

推进城乡一体化的最终目的就是要达到城乡共荣，其中农民问题解决与否成为城乡一体化成败的关键。成都市几个城乡一体化试点城镇的农民对现今政策、生活等方面满意程度如何，也是一个备受关注的问题。通过实地调查，采用模糊数学方法，对成都市的几个城乡一体化试点城镇的农民目前的状况进行综合评价，计算出他们的满意程度，找出存在的问题，为今后城乡一体化的普遍开展提供参考。经过对调查数据的处理计算，结果表明：成都市城乡一体化试点城镇的农民的满意程度处于满意和一般满意状况。  相似文献   

青海省泥石流预警模型     

肖宏斌李有宏  王青川李海红 《气象科技》2006,34(6):754-757

根据野外考察和分析,利用模糊数学方法,定义了青油省玉树州结古镇泥石流沟固有危险度,并以分段函数的形式定义了夏季泥石流降水指数,初步建立了当地泥石流危险度的二级综合判别预警模型。对玉树州结古镇5条泥石流沟的危险度做了判别,对不同降水级别所对应的泥石流危险度进行预报,得出相应的预警等级。并以2003年7月29日结古镇北山泥石流为例,对该模型的有效性进行了初步检验。  相似文献