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1.
李飞雪  李满春  赵书河 《遥感信息》2003,(3):23-25,T004
本文提出了一种新的基于Kohonen神经网络与决策树相结合模型的遥感图像自动分类方法。选取绍兴地区为实验区,对TM图像进行了分类实验。并将该模型分类结果与基于Kohonen网络模型的分类结果进行了比较,发现对于江南低山丘陵河网密集区的TM图像应用该模型进行分类能够得到较为满意的分类结果,其分类精度可达到85.16%,较之单纯使用Kohonen网络模型提高了20.12%。  相似文献   

2.
变精度粗集模型在决策树生成过程中的应用   总被引:2,自引:0,他引:2  
Pawlak粗集模型所描述的分类是完全精确的,而没有某种程度上的近似。在利用Pawlak粗集模型构造决策树的过程中,生成方法会将少数特殊实例特化出来,使生成的决策树过于庞大,从而降低了决策树对未来数据的预测和分类能力。利用变精度粗集模型,对基于Pawlak粗集模型的决策树生成方法进行改进,提出变精度明确区的概念,允许在构造决策树的过程中划入明确区的实例类别存在一定的不一致性,可简化生成的决策树,提高决策树的泛化能力。  相似文献   

3.
梁艳红  坎启轩  苏翌 《计算机工程》2019,45(10):221-226
在对类别模糊的文本进行分类时,主题模型只考虑文档和主题级别信息,未考虑底层词语间的隐含信息,且多数主题信息复杂、中心不明确。为此,提出一种改进的文本分类方法。通过分位数选择中心明确的主题,将其映射到word2vec词向量空间内,对模糊文本进行分类操作,进而得到文本分类结果。实验结果表明,与C_LCD+KNN方法相比,该方法分类效果较好,鲁棒性较强。  相似文献   

4.
一种快速的文本聚类-分类法   总被引:4,自引:0,他引:4  
本文提出了文本分类的一种新方法,该方法是将部分文献的内容词进行聚类,根据聚类的结果生成分类模型,再根据朴素的贝叶斯原理将文献进行归类。  相似文献   

5.
王守信  雷雷  马娜 《计算机工程》2008,34(20):43-45
在本体建模中,概念分类结构不明确,缺少理论指导,本体建模方法也欠缺特定本体描述语言定制能力。针对这种情况,该文将本体基础理论与UML本体承诺相结合,提出基于本体基础理论和UML元模型扩展的核心本体元模型及其扩展方法,并以Web本体描述语言为例,对核心本体元模型的扩展能力及扩展方法的有效性进行了验证。  相似文献   

6.
框架消歧指的是在给定的句子中根据目标词的上下文语境,自动识别出有歧义的目标词所属的框架。针对传统FrameNet框架消歧方法使用单一分类模型时没有考虑到目标词之间的联系而导致隐性特征难以被提取,以及分类结果比较依赖分类模型的性能及参数的设置的问题,提出了一种基于SVM和CRF双层模型的FrameNet框架消歧方法。该方法利用分治思想将框架消歧问题转化为对目标词的分类及序列标注。第一层SVM模型对输入的语料进行粗分类,得到分类标签序列;第二层CRF模型将文本序列和SVM模型的分类标签序列作为输入,将分类标签加入特征模板进一步进行序列标注。实验选取了FrameNet语义知识库中能够激起多个框架的18个词元,2?614条例句作为实验数据。实验结果显示,与传统方法相比,基于SVM和CRF的双层模型有较高的准确率,证明了该方法是一种较为适用的FrameNet框架消歧方法。  相似文献   

7.
使用最大熵模型进行中文文本分类   总被引:51,自引:1,他引:51  
随着WWW的迅猛发展,文本分类成为处理和组织大量文档数据的关键技术.由于最大熵模型可以综合观察到各种相关或不相关的概率知识,对许多问题的处理都可以达到较好的结果.但是,将最大熵模型应用在文本分类中的研究却非常少,而使用最大熵模型进行中文文本分类的研究尚未见到.使用最大熵模型进行了中文文本分类.通过实验比较和分析了不同的中文文本特征生成方法、不同的特征数目,以及在使用平滑技术的情况下,基于最大熵模型的分类器的分类性能.并且将其和Baves,KNN,SVM三种典型的文本分类器进行了比较,结果显示它的分类性能胜于Bayes方法,与KNN和SVM方法相当,表明这是一种非常有前途的文本分类方法.  相似文献   

8.
通过对浏览器安全漏洞的形成原因和利用效果进行分析,并利用层次分类模型,提出了一种基于AHP模型的浏览器安全漏洞分类方法。该方法从漏洞成因和攻击效果两个维度上对浏览器安全漏洞进行分类,并把分类结果与CNNVD的分类方法的分类结果进行了对比,结果表明本文的分类方法具有更好的适用性。  相似文献   

9.
一种概率过程神经元网络模型及分类算法   总被引:2,自引:0,他引:2  
针对动态信号分类及与先验类别知识融合问题,提出了一种概率过程神经元网络模型.模型将贝叶斯概率分类机制与过程神经元网络动态信号处理方法相结合,通过在前馈过程神经元网络中增加一个模式单元层,以及采用归一化指数类型激励函数,实现基于贝叶斯规则的动态信号分类.分析了概率过程神经元网络分类机制与贝叶斯分类规则的等价性,给出了具体的学习算法,实验结果验证了模型和算法的有效性.  相似文献   

10.
支持向量机在显微图像分类中的应用研究   总被引:1,自引:0,他引:1  
张宪  李晓娟 《计算机应用》2008,28(3):790-791
根据微生物显微图像中微生物形态各异、目标重叠、灰度接近等特性,提出了一种新的显微图像分类识别方法。该方法利用变差函数对微生物显微图像纹理信息进行特征提取,根据支持向量机模式识别原理建立分类识别模型。将该方法应用于两类微生物分类,并与基于神经网络方法的分类结果进行对比分析,结果表明,该方法具有较高的分类精度。  相似文献   

11.
A self-organizing Takagi-Sugeno (TS)-type fuzzy network with support vector learning (SOTFN-SV) is proposed in this paper. The proposed SOTFN-SV is inspired by analysis of TS-type fuzzy systems and composite-kernel support vector machine (SVM). SOTFN-SV is a fuzzy system constructed by the hybridization of fuzzy clustering and SVM. The antecedent part of SOTFN-SV is generated via fuzzy clustering of the input data, and then SVM is used to tune the consequent part parameters to give the network better generalization performance. For demonstration, SOTFN-SV is applied to several classification problems, especially the skin color classification problem. In the skin color classification application, each color pixel is represented by hue and saturation (HS) color space. To represent color information by histogram as accurately as possible, a nonuniform partition of HS space is proposed. For comparison, SVMs and other fuzzy systems trained by SVM or neural networks are applied to the same classification problems. The advantages of SOTFN-SV are verified by comparisons with the results of these methods.  相似文献   

12.
基于模糊高斯基函数神经网络的遥感图像分类   总被引:8,自引:0,他引:8       下载免费PDF全文
针对遥感图像分类的特点,提出了一种基于模糊高斯基函数神经网络的遥感图像分类器。该分类器将模糊技术与神经网络相结合,采用神经网络来实现模糊推理,利用神经网络的学习能力来达到调整模糊隶属函数和模型规则的目的,从而使系统具备了自适应的特性,实验结果表明,这种基于模糊高斯基孙数神经网络的分类器经过训练后,可应用于遥感图像的分类,其分类精度明显高于传统的最大似然分类法。  相似文献   

13.
模糊聚类分析是一种重要的分类方法。传统模糊聚类分析法着眼于全体属性,在对多属性数据集分类方面具有明显优势,对基于特定、重要属性的分类时显得不足。本文对传统方法进行改进,提出了一种基于特征属性分类的模糊聚类方法,利用特征属性进行分类,产生了较好的分类效果,展示了一个成用实例。改进的方法人人提高了特定分类问题的应用价值。  相似文献   

14.
In this study, a fuzzy‐spectral mixture analysis (fuzzy‐SMA) model was developed to achieve land use/land cover fractions in urban areas with a moderate resolution remote sensing image. Differed from traditional fuzzy classification methods, in our fuzzy‐SMA model, two compulsory statistical measurements (i.e. fuzzy mean and fuzzy covariance) were derived from training samples through spectral mixture analysis (SMA), and then subsequently applied in the fuzzy supervised classification. Classification performances were evaluated between the ‘estimated’ landscape class fractions from our method and the ‘actual’ fractions generated from IKONOS data through manual interpretation with heads‐up digitizing option. Among all the sub‐pixel classification methods, fuzzy‐SMA performed the best with the smallest total_MAE (MAE, mean absolute error) (0.18) and the largest Kappa (77.33%). The classification results indicate that a combination of SMA and fuzzy logic theory is capable of identifying urban landscapes at sub‐pixel level.  相似文献   

15.
GA-fuzzy modeling and classification: complexity and performance   总被引:11,自引:0,他引:11  
The use of genetic algorithms (GAs) and other evolutionary optimization methods to design fuzzy rules for systems modeling and data classification have received much attention in recent literature. Authors have focused on various aspects of these randomized techniques, and a whole scale of algorithms have been proposed. We comment on some recent work and describe a new and efficient two-step approach that leads to good results for function approximation, dynamic systems modeling and data classification problems. First, fuzzy clustering is applied to obtain a compact initial rule-based model. Then this model is optimized by a real-coded GA subjected to constraints that maintain the semantic properties of the rules. We consider four examples from the literature: a synthetic nonlinear dynamic systems model, the iris data classification problem, the wine data classification problem, and the dynamic modeling of a diesel engine turbocharger. The obtained results are compared to other recently proposed methods  相似文献   

16.
In this paper a suitable neural classification algorithm, based on the use of Adaptive Resonance Theory (ART) networks, is applied to the fusion and classification of optical and SAR urban images. ART networks provide a flexible tool for classification, but are ruled by a large number of parameters. Therefore, the simplified ART2-A algorithm is used in this paper, and the neural approach is integrated into a classification chain where fuzzy clustering for merging of classes is also considered. The interaction between the two methods leads to encouraging results in less CPU time than classification with fuzzy clustering alone or other classical approaches (ISODATA). Examples of classification are provided using C-band total power AIRSAR data and optical images of Santa Monica, Los Angeles.  相似文献   

17.
Classification is one of the most popular data mining techniques applied to many scientific and industrial problems. The efficiency of a classification model is evaluated by two parameters, namely the accuracy and the interpretability of the model. While most of the existing methods claim their accurate superiority over others, their models are usually complex and hardly understandable for the users. In this paper, we propose a novel classification model that is based on easily interpretable fuzzy association rules and fulfils both efficiency criteria. Since the accuracy of a classification model can be largely affected by the partitioning of numerical attributes, this paper discusses several fuzzy and crisp partitioning techniques. The proposed classification method is compared to 15 previously published association rule-based classifiers by testing them on five benchmark data sets. The results show that the fuzzy association rule-based classifier presented in this paper, offers a compact, understandable and accurate classification model.  相似文献   

18.
Induction of descriptive fuzzy classifiers with the Logitboost algorithm   总被引:3,自引:3,他引:0  
Recently, Adaboost has been compared to greedy backfitting of extended additive models in logistic regression problems, or “Logitboost". The Adaboost algorithm has been applied to learn fuzzy rules in classification problems, and other backfitting algorithms to learn fuzzy rules in modeling problems but, up to our knowledge, there are not previous works that extend the Logitboost algorithm to learn fuzzy rules in classification problems.In this work, Logitboost is applied to learn fuzzy rules in classification problems, and its results are compared with that of Adaboost and other fuzzy rule learning algorithms. Contradicting the expected results, it is shown that the basic extension of the backfitting algorithm to learn classification rules may produce worse results than Adaboost does. We suggest that this is caused by the stricter requirements that Logitboost demands to the weak learners, which are not fulfilled by fuzzy rules. Finally, it is proposed a prefitting based modification of the Logitboost algorithm that avoids this problem  相似文献   

19.
基于模糊积分和遗传算法的分类器组合算法   总被引:3,自引:0,他引:3  
将多个分类器进行组合能提高分类精度。基于模糊测度的Sugeno和Choquet积分具有理想的特性,因此该文利用其进行分类器组合。然而在实际中难以求得模糊测度。该文利用两种方法求取模糊测度,一是分类器对样本数据的分类能力,另一种是根据遗传算法。这两种方法均考虑了每个分类器对不同类的分类能力不同这一经验知识。实验中对UCI中的几个数据库进行了测试,同时将该组合方法应用于一多传感器融合工件识别系统。测试结果表明了该算法是一种计算简便、精度较高的分类器组合方法。  相似文献   

20.
提出一种基于支持向量机学习的模糊分类束纯模型.通过将支持向量机映射成等价的模糊分类系统,支持向量机的稀疏性表示等特性使得相应的模糊分类系统避免了“维数灾难”问题,并具有良好的泛化能力.另一方面,模糊系统的一些理论和应用成果也可用来进一步改善分类系统的性能.本文根据模糊集合的贴近度概念对模糊系统的语言变量进行约简,合并冗余的和不一致的模糊规则,然后采用粒子群优化方法改善模糊分类系统性能.该方法增强了系统的泛化能力,并可以理解为解决支持向量机中难以确定的系统参数问题的一种辅助方法.实验结果表明了该方法的可行性和有效性.  相似文献   

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