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基于R-树索引的高维相似重复记录检测改进算法 被引量:3
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作者 宋国兴 周喜 +1 位作者 马博 赵凡 《微电子学与计算机》 CSCD 北大核心 2017年第9期97-102,共6页
经典的相似重复记录检测算法SNM算法随着记录维度的增加,投影过程不仅会导致数据丢失,算法的误差率也会明显增大.针对SNM算法的不足,提出DRR算法,利用R-树构建索引保留记录的高维空间特性,通过聚类减少记录在叶子节点中的比较次数提高效... 经典的相似重复记录检测算法SNM算法随着记录维度的增加,投影过程不仅会导致数据丢失,算法的误差率也会明显增大.针对SNM算法的不足,提出DRR算法,利用R-树构建索引保留记录的高维空间特性,通过聚类减少记录在叶子节点中的比较次数提高效率,同时改进度量记录相似性的距离算法,避免高维数据稀疏性的影响.最后,通过真实数据在不同维度上分别与SNM算法进行对比,验证了算法的有效性. 展开更多
关键词 SNM算法 R-树索引 高维空间特性 改进距离算法 数据稀疏性
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Real-time road traffic states estimation based on kernel-KNN matching of road traffic spatial characteristics 被引量:2
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作者 XU Dong-wei 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第9期2453-2464,共12页
The accurate estimation of road traffic states can provide decision making for travelers and traffic managers. In this work,an algorithm based on kernel-k nearest neighbor(KNN) matching of road traffic spatial charact... The accurate estimation of road traffic states can provide decision making for travelers and traffic managers. In this work,an algorithm based on kernel-k nearest neighbor(KNN) matching of road traffic spatial characteristics is presented to estimate road traffic states. Firstly, the representative road traffic state data were extracted to establish the reference sequences of road traffic running characteristics(RSRTRC). Secondly, the spatial road traffic state data sequence was selected and the kernel function was constructed, with which the spatial road traffic data sequence could be mapped into a high dimensional feature space. Thirdly, the referenced and current spatial road traffic data sequences were extracted and the Euclidean distances in the feature space between them were obtained. Finally, the road traffic states were estimated from weighted averages of the selected k road traffic states, which corresponded to the nearest Euclidean distances. Several typical links in Beijing were adopted for case studies. The final results of the experiments show that the accuracy of this algorithm for estimating speed and volume is 95.27% and 91.32% respectively, which prove that this road traffic states estimation approach based on kernel-KNN matching of road traffic spatial characteristics is feasible and can achieve a high accuracy. 展开更多
关键词 road traffic kernel function k nearest neighbor (KNN) state estimation spatial characteristics
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A Class Curves with Some Geometric and Physical Properties in a Higher Dimensional Space
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作者 JIA Xing-qin LI Xian 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第3期289-295,共7页
In this paper, we have considered a class curves with some geometric properties in a higher dimensional space and obtained the differential equation of such a class curves, which are called the hyperbolas. We have con... In this paper, we have considered a class curves with some geometric properties in a higher dimensional space and obtained the differential equation of such a class curves, which are called the hyperbolas. We have considered also hyperbola-preserving conformal transformation and the relevant physical sense. And therefore obtained other invariant properties under the illustrious concircular transformation. 展开更多
关键词 Riemannian space HYPERBOLA CURVATURE conformal transformation
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Fault Diagnosis Based on MultiKernel Classification and Information Fusion Decision
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作者 Mohammad Reza Vazifeh Pan Hao Farzaneh Abbasi 《Computer Technology and Application》 2013年第8期404-409,共6页
In machine learning and statistics, classification is the a new observation belongs, on the basis of a training set of data problem of identifying to which of a set of categories (sub-populations) containing observa... In machine learning and statistics, classification is the a new observation belongs, on the basis of a training set of data problem of identifying to which of a set of categories (sub-populations) containing observations (or instances) whose category membership is known. SVM (support vector machines) are supervised learning models with associated learning algorithms that analyze data and recognize patterns, used for classification and regression analysis. The basic SVM takes a set of input data and predicts, for each given input, which of two possible classes fon^as the output, making it a non-probabilistic binary linear classifier. In pattern recognition problem, the selection of the features used for characterization an object to be classified is importance. Kernel methods are algorithms that, by replacing the inner product with an appropriate positive definite function, impticitly perform a nonlinear mapping 4~ of the input data in Rainto a high-dimensional feature space H. Cover's theorem states that if the transformation is nonlinear and the dimensionality of the feature space is high enough, then the input space may be transformed into a new feature space where the patterns are linearly separable with high probability. 展开更多
关键词 Fault diagnosis wavelet-kernel information fusion multi classification.
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Kernelized fourth quantification theory for mineral target prediction
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作者 CHEN Yongliang LI Xuebin LIN Nan 《Global Geology》 2011年第4期265-278,共14页
This paper presents a nonlinear multidimensional scaling model, called kernelized fourth quantifica- tion theory, which is an integration of kernel techniques and the fourth quantification theory. The model can deal w... This paper presents a nonlinear multidimensional scaling model, called kernelized fourth quantifica- tion theory, which is an integration of kernel techniques and the fourth quantification theory. The model can deal with the problem of mineral prediction without defining a training area. In mineral target prediction, the pre-defined statistical cells, such as grid cells, can be implicitly transformed using kernel techniques from input space to a high-dimensional feature space, where the nonlinearly separable clusters in the input space are ex- pected to be linearly separable. Then, the transformed cells in the feature space are mapped by the fourth quan- tifieation theory onto a low-dimensional scaling space, where the sealed cells can be visually clustered according to their spatial locations. At the same time, those cells, which are far away from the cluster center of the majority of the sealed cells, are recognized as anomaly cells. Finally, whether the anomaly cells can serve as mineral potential target cells can be tested by spatially superimposing the known mineral occurrences onto the anomaly ceils. A case study shows that nearly all the known mineral occurrences spatially coincide with the anomaly cells with nearly the smallest scaled coordinates in one-dimensional sealing space. In the case study, the mineral target cells delineated by the new model are similar to those predicted by the well-known WofE model. 展开更多
关键词 kernel function feature space fourth quantification theory nonlinear transformation mineral target prediction
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