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1.
为克服马氏距离判别模型无法考虑指标权重的不足,引入粗糙集理论,通过分析评判方法对评价对象的支持度和重要性计算得到权重系数。将权重系数嵌入距离判别模型,构建了边坡稳定性预测的加权距离判别模型。根据边坡失稳破坏特点,选取合理的判别因子,以大量工程实例样本作为原始数据和训练样本,建立了边坡稳定性评价预测的粗糙集-距离判别模型。将边坡稳定性评价预测的粗糙集-距离判别模型评价预测结果与马氏距离判别法、支持向量机理论、Bayes判别分析等方法得到的预测结果进行了对比分析,验证了粗糙集-距离判别模型的有效性。将建立的粗糙集-距离判别模型应用于黄河中游地区某大型水利枢纽库区边坡工程,预测结果与实际情况吻合。研究结果表明,粗糙集-距离判别模型具有权重分析合理、预测准确性高等优点,是进行边坡稳定性分析预测的一种新的有效途径。  相似文献   

2.
关维娟  许光泉  陈明强  许峰 《地下水》2014,(1):40-42,47
对Bayes逐步判别法在矿井突水水源判别中的应用进行研究分析。选用六大常规离子( Ca2+、Mg2+、K++Na+、SO42-、Cl-、HCO3-)作为判别因子,建立Bayes逐步判别分析模型,以内蒙唐家汇矿区突水水源判别为例,在建立的判别模型回判检验准确率仅60%,分析原因可能与选定的特征判别因子对该矿区水样分类影响能力较弱有关。增加总硬度、碱度、PH值和矿化度作为判别因子,重新建立Bayes判别分析模型,使回判准确率提高至90%,证明适当增加特征判别因子对改善Bayes逐步判别模型的可靠性和稳定性有利。经对唐家会矿区的3个未知样本进行了判别分析,并与距离判别法和模糊综合评判法判别结果对比,结果表明Bayes逐步判别模型准确性较好,判别准确率与距离判别结果完全相同,而优于模糊综合评判方法。在合理选取特征判别因子的情况下,Bayes逐步判别法是目前矿井突水水源判别的有效方法。  相似文献   

3.
如何准确地判识和评价滑坡的稳定性一直是滑坡研究中的关键问题。基于多分类支持向量机的基本理论,利用三峡库区的37个典型滑坡(27个训练样本,10个测试样本),建立了滑坡稳定性判识的多分类支持向量机模型,并与距离判别分析方法进行了比较。结果表明,SVM模型对测试样本和训练样本的判识准确率均达到100%,而距离判别法对测试样本和训练样本的判识准确率分别为80%和77.8%,前者的判识精度明显优于后者。在此基础上,将SVM模型运用于溪洛渡库区牛滚凼滑坡的稳定性判识中,结果与实际情况吻合较好。  相似文献   

4.
赵洪波 《岩土力学》2005,26(2):235-238
围岩的破坏受到多种因素的影响,并且各破坏模式之间没有明显的界限,因此其破坏模式的识别是一种模糊、非线性、小样本、高维数的模式识别问题。支持向量机(SVM)是最近发展起来的一种新机器学习技术,已在模式识别领域有很多成功地应用。基于支持向量机的思想,提出了围岩破坏模式识别的支持向量机方法,很好地表达了围岩破坏模式与其影响因素之间的复杂非线性关系。具体算例表明,该方法是可行的,具有一定的准确性。  相似文献   

5.
以淮南潘二矿区、山西河池矿区和河南焦作矿区水样作为突水水源数据,采用距离判别分析理论,对突水水源进行判别分析。选用六大常规离子作为判别因子,分别建立矿井突水水源的距离判别分析模型。经回判检验表明,潘二水样和焦作水样的距离判别模型回判准确率超过90%,而河池矿区水样距离判别模型的回判准确率仅50%。为此,增加总硬度、碱度、PH值和矿化度作为判别因子,重新建立河池矿区水样的距离判别分析模型,回判准确率提高至90%,证明适当增加特征判别因子对改善距离判别分析模型的判别准确率有利。最后对三个矿区的未知样本进行了距离判别分析,并与Bayes逐步判别法和模糊综合评判法判别结果对比,结果表明距离判别法稳定性较好,判别准确率与Bayes逐步判别基本相同,比模糊综合评判要好。因此,在判别因子选择合适的情况下,距离判别法是目前矿井突水水源判别的有效方法。  相似文献   

6.
宫凤强  李夕兵  张伟 《岩土力学》2010,31(Z1):370-377
在岩爆发生和烈度分级预测的距离判别分析模型的基础上,结合地下工程岩爆的特点和Bayes判别分析理论,提出了地下工程岩爆发生及烈度分级预测的Bayes判别分析方法。综合分析影响岩爆主要因素,选取最大切向应力 、岩石抗压强度 、岩石抗拉强度 和弹性能量指数 作为判别因子建立岩爆预测的Bayes判别分析模型,并利用回代估计法对误判概率进行估计。利用国内外一些重大深部地下工程实例作为学习的样本进行训练建模,经过训练后的模型回判估计的误判率为0。利用该模型对国内3处典型的隧道岩爆情况进行预测,结果与实际情况符合得很好。研究结果表明,Bayes判别模型在岩爆发生可能性及烈度分级预测中具有良好的适用性和有效性。  相似文献   

7.
准确有效地判别突水水源是解决矿井水害的前提条件。基于淮北袁店二矿各含水层共59个水样水质化验资料,利用主成分分析法,计算各水样的因子得分,并进行系统聚类,剔除错误样本。利用剩余水样作为学习样本,检验Bayes判别函数的判定准确性,得出准确率为92.5%,并进行交叉验证。利用该判别函数对某工作面底板下一富水区水样进行判别,结果与实际情况吻合。结果指示基于主成分分析与Bayes判别法较单一Bayes判别法更加准确,能够消除样本变量之间的相互影响,实现对突水水源的快速有效判别。   相似文献   

8.
砂砾岩储集体为快速沉积环境下形成的沉积物,具有很强的非均质性,因此,利用测井数据进行岩性识别的结果准确性较差。笔者针对该问题,从砂砾岩储集体中岩性测井特征提取和模式识别算法2方面进行分析。在测井特征提取上,针对其粒度跨度大、成分复杂、过渡岩性测井特征多样的特点,利用沉积相、物源体系控制岩石的成分和结构特征的多样性,达到准确提取岩石骨架颗粒参数的目的。在模式识别算法上,选取支持向量机、极限学习机和概率神经网络3种基于不同分类原理的模式识别算法,构建SEP岩性判别算法。在松辽盆地南部梨树断陷下白垩统营城组砂砾岩储集体岩性识别中,采用SEP法,利用GR-AC-CNL-DEN-RLLD-w(K-PE测井数据组合,对13口钻井的284块样本岩性进行判别,SEP识别结果与3种单方法相比,能够提高岩性判别结果的准确性和稳定性,识别符合率均值达到83.64%。  相似文献   

9.
以贵州北部一茶叶园区80个表层土壤样品为研究对象,对其Hg、As、Cd、Pb、Cr和Cu含量进行测定,在MATLAB中应用支持向量机构建土壤环境质量评价模型,并与模糊综合评价法和内梅罗综合污染指数法的评价结果对比分析,探究支持向量机模型在喀斯特山区土壤环境质量评价中的适用性,其结果表明:研究区土壤质量Ⅰ类与Ⅱ类样品比例为33∶7,土壤环境质量大多数为I类;支持向量机方法的评价结果与模糊综合评价法和内梅罗综合污染指数法结果的相同率分别达到82.5%和80.0%,并分析结果有差异的样品,发现支持向量机评价结果更符合实际情况,这说明该模型适用于土壤环境质量的评价。   相似文献   

10.
机器学习在滑坡的易发性评价中面临两个难点,一是评价指标的客观量化,二是训练样本的选择。鉴于此,采用频率比法实现了评价指标的客观量化,利用k均值聚类算法实现了非滑坡样本数据的筛选。结果表明,以k均值聚类算法筛选非滑坡为前提,神经网络的训练精度由73%提升到了97%,支持向量机的训练精度由75%提升到了96%。基于GIS平台,将神经网络和支持向量机模型计算的全区易发性指数按自然断点法分为五个区域,分区图与历史灾害点的叠加分析统计结果显示,神经网络在全局范围内的评价结果优于支持向量机模型,全局精度分别为76%和74%。研究结果可为南江县的防灾减灾工作提供参考。  相似文献   

11.
The aim of this study is the application of support vector machines (SVM) to landslide susceptibility mapping. SVM are a set of machine learning methods in which model capacity matches data complexity. The research is based on a conceptual framework targeted to apply and test all the procedural steps for landslide susceptibility modeling from model selection, to investigation of predictive variables, from empirical cross-validation of results, to analysis of predicted patterns. SVM were successfully applied and the final susceptibility map was interpreted via success and prediction rate curves and receiver operating characteristic (ROC) curves, to support the modeling results and assess the robustness of the model. SVM appeared to be very specific learners, able to discriminate between the informative input and random noise. About 78% of occurrences was identified within the 20% of the most susceptible study area for the cross-validation set. Then the final susceptibility map was compared with other maps, addressed by different statistical approaches, commonly used in susceptibility mapping, such as logistic regression, linear discriminant analysis, and naive Bayes classifier. The SVM procedure was found feasible and able to outperform other techniques in terms of accuracy and generalization capacity. The over-performance of SVM against the other techniques was around 18% for the cross-validation set, considering the 20% of the most susceptible area. Moreover, by analyzing receiver operating characteristic (ROC) curves, SVM appeared to be less prone to false positives than the other models. The study was applied in the Staffora river basin (Lombardy, Northern Italy), an area of about 275 km2 characterized by a very high density of landslides, mainly superficial slope failures triggered by intense rainfall events.  相似文献   

12.
As the basal group of Polypodiales, the specific taxonomy of Dicksoniaceae is still being debated. As aquantitative analysis method, numerical taxonomy has been applied to the taxonomic study of many plant families andgenera in recent years due to its simplicity and high accuracy. However, the numerical analysis of the Dicksoniaceae fossilshas not been reported at present. In the present study, the pinnule morphological data of 42 Mesozoic fossil species of theDicksoniaceae were analyzed using cluster analysis, principal component analysis and correlation analysis. The resultsrevealed that 42 taxonomic units could be divided into six representative groups, which are consistent with the traditionaltaxonomy. After screening, an identification key on 28 fossil species of four genera with a definite taxonomic position wasestablished. According to the quantitative analysis, a Bayes discriminant model was established for the selected species.Lastly, the model was tested using the morphological data of the fossil pinnules in Dicksoniaceae from the YaojieFormation, suggesting that the discriminant model is accurate to a certain extent. As a result, the numerical taxonomy canbe applied to the classification of the Dicksoniaceae fossils.  相似文献   

13.
辛176区块沙四段储层存在粗砂岩、不等粒砂岩和细砂岩,岩性非均质性较强.“四性”关系研究表明,岩性的准确识别是正确评价储层静态参数,识别油水层特别是低阻油层的前提.这里介绍了Bayes逐步判别方法原理和技术流程,在应用有序聚类分析方法开展测井曲线自动分层的基础上,综合应用自然电位(SP)、自然伽玛(GR)、声波时差(AC)、深探测电阻率(Rt)、浅探测电阻率(Rxo)测井资料和岩心分析资料,建立了粗砂岩、不等粒砂岩、细砂岩和泥岩的判别函数.应用效果表明,Bayes逐步判别法识别岩性符合率达到了86%,能够满足辛176区块沙四段储层岩性识别的需要.  相似文献   

14.
SVM and SAM classifiers for the lithological mapping using Hyperion data in parts of Gadag schist belt of western Dharwar craton, Karnataka, India were used. The main objective of the present study is to assess and compare the potential use of Hyperion data set for lithological mapping. Accuracy assessment of the derived thematic maps was based on the analysis of the confusion matrix statistics computed for each classification map. For consistency, the same set of validation points were used in evaluating the accuracy of the lithological thematic maps produced. On the basis of the accuracy assessment results, it appears that SVM generally outperformed the SAM classifier in both OA accuracy and individual classes’ accuracies. OA accuracy and Kc for SVM is 96.93% and 0.9655, whereas for SAM it is 74.02% and 0.7085 respectively. SVM classification is the best in describing the spatial distribution and the cover density of each lithology, as was also indicated from the statistics of the individual class results. The individual class accuracy were also analyzed for the SVM and the result show that PA ranges from 87% to 100% and UA ranges from 91% to 100%, whereas for SAM ranges from 15% to 95%, and from 31% to 100% respectively. The SVM method could effectively classify and improve on the existing geological map for the Gadag schist belt (GSB) using hyperspectral data. The results could be validated through field visits. Therefore, it is concluded that hyperspectral remote sensing data can be efficiently used to improve existing maps, especially in areas where same rock types show variable degree of alteration over smaller spatial scales.  相似文献   

15.
The product of the mining industry (ore) is considered to be the raw material for the metal industry. The destination policy of the raw materials of iron mine is highly dependent on the class of iron ores. Thus, regular monitoring of iron ore class is the urgent need at the mine for accurately assigning the destination policy of raw materials. In most of the iron ore mines, decisions on ore class are made based on either visual inspection by the geologist or laboratory analyses of the ores. This process of ore class estimation is time consuming and also challenging for continuous monitoring. Thus, the present study attempts to develop an online vision-based technology for classification of iron ores. A laboratory-scale transportation system is designed using conveyor belt for online image acquisition. A multiclass support vector machine (SVM) model was developed to classify the iron ores. A total of 2200 images were captured for developing the ore classification model. A set of 18 features (9-histogram-based colour features in red, green and blue (RGB) colour space and 9-texture features based on intensity (I) component of hue, saturation and intensity (HSI) colour space) were extracted from each image. The performance of the SVM model was evaluated using four confusion matrix parameters (sensitivity, accuracy, misclassification and specificity). The SVM model performance was also compared with the other methods like K-nearest neighbour, classification discriminant, Naïve Bayes, classification tree and probabilistic neural network. It was observed that the SVM classification model performs better than the other classification methods.  相似文献   

16.
Bayes方法在矿井突水水源判别中的应用   总被引:1,自引:0,他引:1  
快速有效地判别突水水源是矿井安全生产的重要保障。选取各含水层多项水质指标,应用Bayes方法建立适用于不同水质类型的矿井突水水源快速判别模型。结合SPSS软件,以淮南顾桥矿为例,并与模糊综合评判模型、神经网络模型进行分析比较。结果表明:贝叶斯多类线性判别模型能够有效地判别突水水源,比模糊综合评判有更高的准确性,与神经网络模型的判别准确率相同。Bayes多类线性判别模型又以其计算过程简单、模型结构稳定而优于神经网络模型。既提高判别准确率又提高判别速度,实现对突水水源快速有效判别。   相似文献   

17.
Few strong relationships exist along the Chesapeake Bay shoreline between the historic erosion rate and the distribution of any of several coastal parameters which were defined and tested using traditional regression and discriminant analysis procedures To develop a simple predictive equation for shore erosion that could be used by coastal managers, the entire Chesapeake Bay shoreline was partitioned into naturally occurring reaches 2–5 km in length, and the historic erosion rate on each reach was modelled as a function of five variables (a) shoreline type, (b) “100-year” storm surge height, (c) mean tide range, (d) wave climate, and (e) potential littoral drift rate The statistical analysis yielded a multiple correlation coefficient (r 2) of 30 8%, discriminant analysis showed only the first two variables listed above are useful predictors (i e, statistically significant) of historic erosion rates A 95-mile portion of the same bay shoreline in Queen Anne’s and Talbot counties was then partitioned into shorter reach lengths (1/2–2km) and more variables were included The multiple correlation coefficient (r 2) improved slightly to 32 9%, but only shoreline type and potential littoral drift rate were found to be useful predictors of historic erosion rates Curiously, the ability to model statistically the historic shore erosion rate is best on those reaches already substantially protected by structures For Queen Anne’s and Talbot counties, the multiple regression coefficient improved to 61 5% when only reaches 1/2–2km in length protected by structures were considered.  相似文献   

18.
高光谱遥感影像分类是高光谱遥感影像处理和应用的重要组成部分。然而,高光谱遥感影像具有波段数量较多和空间分辨率较高等特点,给分类任务带来一定的挑战。为了提高分类精度,充分利用影像的空间信息和像素间的局部信息,提出一种引导滤波联合局部判别嵌入的高光谱影像分类方法。首先,对高光谱遥感影像进行归一化,利用主成分分析方法实现特征提取,将提取的第一主成分影像作为引导图像;其次,采用引导滤波分别提取各波段影像的空间特征;然后,将提取的空间影像特征进行叠加,通过局部Fisher判别分析完成低维嵌入;最后,将得到的低维嵌入特征输入支持向量机分类器得到分类结果。采用Indian Pines和Pavia University两幅高光谱影像进行实验的结果表明:在分别从各类地物中随机选取10%和100个样本作为训练样本的情况下,其总体分类精度分别提高到98.28%和99.45%;对比其他相关方法,该方法能够获取更高的分类精度。该方法在低维嵌入的同时,有效利用了影像的空间信息,改善了分类效果。  相似文献   

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