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41.
In many instances hydrogeological parameters obtained by conventional methods for selected localities within an aquifer or an aquitard are not sufficient for adequate regionalization at the scale of the entire layer. Here, we demonstrate an application of the fuzzy kriging method in regionalization of hydrogeological data, in which the set of conventional, crisp values is supplemented by imprecise information subjectively estimated by an expert. It is believed that such an approach eventually may reflect the real-world conditions more closely than a traditional crisp-value approach, because the former does not impose exactness artificially on phenomena which are diffuse by their nature. Spatial interpolation was done for the thickness of one of the major aquitards (till and glaciolacustrine clay) in northwestern Germany. The dataset consists of 329 crisp values from boreholes supplemented by 172 imprecise values defined as fuzzy numbers. It is demonstrated that the reliability of regionalization was higher, compared to regionalization performed with the crisp dataset only. Fuzzy kriging was performed with FUZZEKS (Fuzzy Evaluation and Kriging System) developed at the Ecosystem Research Center at the University of Kiel.  相似文献   
42.
斜坡稳定性分析的模糊综合评判应用初探   总被引:1,自引:0,他引:1       下载免费PDF全文
采用两级模糊综合评判方法,在对评判实例的稳定性因素的定性分析基础上,选取主要因素四类14项作为稳定性评价指标并将其定量化,按稳定,较稳定,较不稳定和不稳定四个级别进行综合评判,评判结果与斜坡的实际情况有较好的一致性。  相似文献   
43.
古潜山火成岩裂缝带划分与孔隙度计算   总被引:3,自引:0,他引:3  
针对火成岩岩性成分复杂,常规测井难以正确划分岩性,严重阻碍了储层参数的定量计算。本文提出模糊聚类划分岩性,采用综合概率法与混合体积模型计算裂缝孔隙度、有效孔隙度等参数。其测井解释结果与井壁取心和地质描述资料对照,完全吻合。  相似文献   
44.
Grade estimation using fuzzy- set algorithms   总被引:1,自引:0,他引:1  
This paper presents a new approach for estimating unknown ore grades within a mining deposit in a fuzzy environment using fuzzy c- means clustering and a fuzzy inference system. Based on a collection of cluster centers obtained from fuzzy c- means, a fuzzy rule base and fuzzy search domains are established to compute grades at these cluster centers. These cluter center- grade pairs act as control information in the fuzzy space- grade system in order to infer unknown grades on the basis of fuzzy interpolation, fuzzy extrapolation, and a defuzzification process of fuzzy control.  相似文献   
45.
基于小波分解的西太平洋副热带高压模糊推理预测   总被引:3,自引:2,他引:3  
基于NCEP/NCAR再分析资料,讨论了西太平洋副高脊线与其前期位置的相互关系,并在此基础上用小波分解和自适应模糊推理方法,对副高脊线进行集成建模和预测.基于小波分解重构的副高脊线短期活动集成预测结果表明,该方法可有效降低预报难度,明显改进和提高了副高脊线短期活动的预报准确率.  相似文献   
46.
Automated reconstruction of building objects from aerial images is a complex problem due to the diversity of buildings as well as noise and low contrast of images, which are the results of distant photography, atmospheric effects and poor illumination. In this paper, a semi-automated approach to the reconstruction of parametric building models from aerial images is presented, which works with line segments extracted from the image. The model is selected interactively from a library of parametric models. A perceptual grouping technique is used to select the most significant image lines in terms of relations such as proximity and parallelism. Model lines are searched for the same relations as in the grouped image lines, and the corresponding lines undergo a matching procedure, which determines whether or not a match can be found between the given model and image lines. An experiment with aerial images of flat-roof and gable-roof buildings is shown and its results indicate the robustness and efficiency of the proposed approach.  相似文献   
47.
Fuzzy set approaches to classification of rock masses   总被引:6,自引:0,他引:6  
A. Aydin   《Engineering Geology》2004,74(3-4):227-245
Rock mass classification is analogous to multi-feature pattern recognition problem. The objective is to assign a rock mass to one of the pre-defined classes using a given set of criteria. This process involves a number of subjective uncertainties stemming from: (a) qualitative (linguistic) criteria; (b) sharp class boundaries; (c) fixed rating (or weight) scales; and (d) variable input reliability. Fuzzy set theory enables a soft approach to account for these uncertainties by allowing the expert to participate in this process in several ways. Hence, this study was designed to investigate the earlier fuzzy rock mass classification attempts and to devise improved methodologies to utilize the theory more accurately and efficiently. As in the earlier studies, the Rock Mass Rating (RMR) system was adopted as a reference conventional classification system because of its simple linear aggregation.

The proposed classification approach is based on the concept of partial fuzzy sets representing the variable importance or recognition power of each criterion in the universal domain of rock mass quality. The method enables one to evaluate rock mass quality using any set of criteria, and it is easy to implement. To reduce uncertainties due to project- and lithology-dependent variations, partial membership functions were formulated considering shallow (<200 m) tunneling in granitic rock masses. This facilitated a detailed expression of the variations in the classification power of each criterion along the corresponding universal domains. The binary relationship tables generated using these functions were processed not to derive a single class but rather to plot criterion contribution trends (stacked area graphs) and belief surface contours, which proved to be very satisfactory in difficult decision situations. Four input scenarios were selected to demonstrate the efficiency of the proposed approach in different situations and with reference to the earlier approaches.  相似文献   

48.
基于模糊算子理论的道路半自动提取   总被引:2,自引:0,他引:2  
提出了一种基于模糊算子理论的道路半自动提取方法。该方法在对小比例尺影像进行Sobel边缘检测的基础上,定义了12种模糊算子表示2维道路的各种可能的结构,然后在给定道路种子点附近形成的一定范围内进行搜索,提取出道路的中心线。实验结果表明,该算法速度较快并且具有较强的鲁棒性。  相似文献   
49.
提出一种基于高度和彩色纹理信息的目标识别方法 ,其目的是提取具有相对高度的地物。由于传统二维纹理分析的方法往往不能有效地提取这类目标 ,本文把高度、色彩和纹理信息有机地结合起来 ,提高了识别率。依据影像提取结果 ,探讨了树林对森林覆盖地区自动空中三角测量选点的负面影响 ,同时建议采用数据分组的方案来改善森林覆盖地区自动空中三角测量的精度 ,并用对比实验证明了其有效性。  相似文献   
50.
根据地名信息的特点,提出一种基于地名首字母的模糊查询方法。采用Access数据库,结合微软自带的字库实现了地名首字母的提取与入库,特别是解决了多音字在首字母提取及入库时的处理,并提供了一种文件批量输入的方法,实现了基于地名首字母的模糊查询。设计开发的地名查询系统,使用简单,效率也得到了极大的提高,可以获取对应的地理位置,为后继GIS系统开发提供方便。  相似文献   
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