基于混合聚类的岩体结构面优势分组方法     

许扬  张文  符锐  聂振邦  兰志广  陈怀玉  单博 《世界地质》2020,39(1):113-120

提出一种基于凝聚层次法和模糊C均值法的混合聚类法,用于对岩体结构面的优势组划分。该方法将结构面投放到在单位球面上,并使用欧式距离作为极点的相似性度量准则。先剔除结构面数据中的孤值产状,然后用凝聚层次法得到初步聚类结果,并将其作为FCM法的初始聚类中心,最后用FCM法划分优势组。通对人工生成产状样本的分组,验证了该法的正确性。将该方法应用于大藤峡坝址区实测的结构面数据的划分。在实测数据中寻找到两个孤值产状,成功将大藤峡D1y^1-3地层岩体结构面划分为两组,得到了符合实际的分组结果。  相似文献   

高速铁路无砟轨道地基泥岩膨胀性分类分级研究     

薛彦瑾  王起才  马丽娜  张戎令  代金鹏  王强 《岩土力学》2020,41(9):3109-3118

红层泥岩是一种典型侏罗系沉积岩，其含有微量黏土矿物，易遇水软化、失水崩解，具有一定膨胀性，是引起兰新高速铁路路基持续上拱变形的一个重要因素，故重新判定该种土体膨胀性对高速铁路无砟轨道设计和施工具有重要意义。为此，选取等效蒙脱石含量、阳离子交换量、自由膨胀率和液限为泥岩膨胀性判别指标，通过兰新高速铁路上拱地段大量钻孔实测资料，提出了泥岩膨胀等级分级标准，采用改进层次分析法、基尼系数法和直觉模糊理论确定了判别指标组合权重，基于逼近理想解排序法(TOPSIS法)建立了泥岩膨胀性直觉模糊综合评价模型。结果表明：直觉模糊综合评价模型将泥岩膨胀性进行了定量化，克服了同一试样不同指标属于不同等级判别缺陷；室内膨胀量试验验证了膨胀等级分级标准和直觉模糊综合评价模型对兰新高铁地基泥岩适用性和准确性。研究成果对地基红层泥岩高速铁路路基长期持续上拱变形风险评估和工程控制措施提供技术支撑。  相似文献   

Using advanced soft computing techniques for regional shoreline geoid model estimation and evaluation     

Mosbeh R. Kaloop  Mostafa Rabah  Ahmed Zaki 《Marine Georesources & Geotechnology》2018,36(6):688-697

This study aims at evaluating the global geoid model for a regional shoreline fitting using advanced soft computing techniques and global navigation satellite system/leveling measurements. Artificial neural networks, fuzzy logic, and least square support vector machine models are developed and used to fit the global geoid model for the north coastal Egyptian line. In addition, a novel estimation geoid model is designed and evaluated based on the latest global geoid models. The results of the three estimation models show that they can be used to correct the shoreline geoid model, in terms of root mean square error that ranges from 1.7 to 8.5?cm. Moreover, it is found that the least square vector machine model is a competitive approach with certain advantage in solving complex problems represented by missing data.  相似文献   

黄土斜坡稳定性的模糊信息分析法     

王家鼎  冯学才  孟兴民 《山地学报》1991,(1)

本文基于黄土斜坡稳定性的实际资料,利用信息分配、模糊一二级近似推论及信息集中等原因建立了一套黄土斜坡稳定性的评价方法。用这套方法对一些黄土斜坡(非母体)稳定性进行了验证,其结果与实际情况一致。本方法已应用于兰州市滑坡防灾规划和皋兰山三台阁北侧几个滑坡及斜坡稳定性的研究中,效果良好。  相似文献   

FUZZY COMPREHENSIVE EVALUATION OF CONTAINER TRANSPORTATION MODES ALONG THE CHANGJIANG RIVER MAIN LINE AND ITS DELTA AREA   总被引：1，自引：0，他引：1  

ZHANGShi-yu XIAOHan-liang 《中国地理科学(英文版)》2003,13(3):259-261

The Changjiang River (Yangtze) is one of the fastest growth areas of container transportation in Chi-na. Rail, road and water transportation have competed against each other for container transportation in the Chang-jiang River main line and its delta area. It is of significance to assess these different transportation modes scientifi-cally in order to organize container transportation efficiently in this area and make decision for integral plan and construction of transportation system in this area. This paper outlines application of fuzzy comprehensive evaluation to appraise different modes of typical direction of containers. Twelve assessment indexes were decided. Membership functions were formulated. Evaluation results indicated that road transportation was optimal mode in the Changjiang River delta area, however water transportation was the primary way in the Changjiang River main line.  相似文献   

模糊PID控制器在水压机控制系统中的应用     

温海燕  王增强 《成都信息工程学院学报》2006,21(2):256-260

介绍了模糊控制中的设计思想及方法，并采用模糊控制的方法来改进实际生产中PID控制的一些控制难点。将改进方法应用在一大型水压机控制系统中并在实际生产中取得了理想效果。  相似文献   

Quantitative Assessment of the Ecological Vulnerability of Baiyangdian Wetlands in the North China Plain     

TIAN Jinghan  GUO Chenchen  WANG Jianhua 《资源与生态学报(英文版)》2021,12(6):814-821

Quantitative assessment of vulnerability is a core aspect of wetland vulnerability research. Taking Baiyangdian (BYD) wetlands in the North China Plain as a study area and using the ‘cause-result’ model, 23 representative indicators from natural, social, sci-tech and economic elements were selected to construct an indicator system. A weight matrix was obtained by using the entropy weight method to calculate the weight value for each indicator. Based on the membership function in the fuzzy evaluation model, the membership degrees were determined to form a fuzzy relation matrix. Finally, the ecological vulnerability was quantitatively assessed based on the comprehensive evaluation index calculated by using a composite operator to combine the entropy weight matrix with the fuzzy relation matrix. The results showed that the ecological vulnerability levels of the BYD wetlands were comprehensively evaluated as Grade II, Grade Ⅲ, Grade IV, and Grade Ⅲ in 2010, 2011-2013, 2014, and 2015-2017, respectively. The ecological vulnerability of the BYD wetlands increased from low fragility in 2010 to general fragility in 2011-2013, and to high fragility in 2014, reflecting the fact that the wetland ecological condition was degenerating from 2010 to 2014. The ecological vulnerability status then turned back into general fragility during 2015-2017, indicating that the ecological situation of the BYD wetlands was starting to improve. However, the ecological status of the BYD wetlands on the whole is relatively less optimistic. The major factors affecting the ecological vulnerability of the BYD wetlands were found to be industrial smoke and dust emission, wetland water area, ammonia nitrogen, total phosphorus, rate of industrial solid wastes disposed, GDP per capita, etc. This illustrates that it is a systematic project to regulate wetland vulnerability and to protect regional ecological security, which may offer researchers and policy-makers specific clues for concrete interventions.  相似文献   

基于模糊物元模型的中国旅游生态安全评价及障碍因子诊断研究   总被引：1，自引：0，他引：1  

徐少癸  左逸帆  章牧 《地理科学》2021,41(1):33-43

基于DPSIR模型构建旅游生态安全评价指标体系,利用模糊物元模型对中国31个省（市、区）（不含港澳台）旅游生态安全进行动态评价,并运用空间自相关分析空间格局演化特征。同时借助障碍度模型,对旅游生态安全的障碍因子进行诊断。结果表明:① 旅游生态安全呈现出波动增长的“W”型演化趋势。2013—2016年中国旅游生态安全在空间上呈现出“东部高、西部低”的分布格局,但随着时间推移,出现“北部高、南部低;中间高、两边低”的格局变化;② 从全局来看,2013—2017年中国旅游生态安全在空间上呈现出显著的空间集聚分布的特点,但集聚程度有逐渐下降的态势。从局部关联来看,各省旅游生态安全空间分布存在着空间集聚特征和省域间的空间依赖性;③ 各省旅游生态安全障碍因子存在显著差异,障碍度高于10%的障碍因子较多,主要的障碍因子有旅游经济密度、游客密度、烟尘排放、生活垃圾处理率和污水处理率等。因此,在大力发展旅游业时,需充分考虑经济发展程度和旅游生态安全提升能力;同时还要注意旅游政策与环境保护政策的协调性。  相似文献   

基于滨海环境资源特点的大连旅游承载状态评价   总被引：2，自引：0，他引：2  

朱佳玮  孙文章  岳秀峰 《地理科学》2021,41(4):664-673

旅游环境承载力涉及多维度属性相互制约影响,而传统方法中对于各属性间影响程度及游客偏好选择的判定则较多依赖于个体的主观感知。因此,针对处理多属性综合评价中存在的模糊性及主观性,提出基于蒙特卡罗模拟修正的模糊综合评价模型。结果表明,借助上述模糊综合评价修正模型针对大连滨海旅游环境承载力进行解释与分析,成功缓解了在模型度量与数据分析环节所出现的主观偏误缺陷,从而有效提升了大连市滨海旅游景区有关阈值综合评价体系的科学性与稳健性。评价结果表明,当前大连市滨海旅游环境承载力状态可以判定为“适载”;在影响滨海旅游环境承载力的6项要素中,游憩环境要素与气候要素的评价分数较高,最低评分数值指标为景区游客管理状态。  相似文献   

Kriging with imprecise (fuzzy) variograms. I: Theory   总被引：2，自引：0，他引：2  

A. Bardossy  I. Bogardi  W. E. Kelly 《Mathematical Geology》1990,22(1):63-79

Imprecise variogram parameters are modeled with fuzzy set theory. The fit of a variogram model to experimental variograms is often subjective. The accuracy of the fit is modeled with imprecise variogram parameters. Measurement data often are insufficient to create good experimental variograms. In this case, prior knowledge and experience can contribute to determination of the variogram model parameters. A methodology for kriging with imprecise variogram parameters is developed. Both kriged values and estimation variances are calculated as fuzzy numbers and characterized by their membership functions. Besides estimation variance, the membership functions are used to create another uncertainty measure. This measure depends on both homogeneity and configuration of the data.  相似文献