• Title/Summary/Keyword: Linear Features

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Support Vector Machine Based Arrhythmia Classification Using Reduced Features

  • Song, Mi-Hye;Lee, Jeon;Cho, Sung-Pil;Lee, Kyoung-Joung;Yoo, Sun-Kook
    • International Journal of Control, Automation, and Systems
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    • v.3 no.4
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    • pp.571-579
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    • 2005
  • In this paper, we proposed an algorithm for arrhythmia classification, which is associated with the reduction of feature dimensions by linear discriminant analysis (LDA) and a support vector machine (SVM) based classifier. Seventeen original input features were extracted from preprocessed signals by wavelet transform, and attempts were then made to reduce these to 4 features, the linear combination of original features, by LDA. The performance of the SVM classifier with reduced features by LDA showed higher than with that by principal component analysis (PCA) and even with original features. For a cross-validation procedure, this SVM classifier was compared with Multilayer Perceptrons (MLP) and Fuzzy Inference System (FIS) classifiers. When all classifiers used the same reduced features, the overall performance of the SVM classifier was comprehensively superior to all others. Especially, the accuracy of discrimination of normal sinus rhythm (NSR), arterial premature contraction (APC), supraventricular tachycardia (SVT), premature ventricular contraction (PVC), ventricular tachycardia (VT) and ventricular fibrillation (VF) were $99.307\%,\;99.274\%,\;99.854\%,\;98.344\%,\;99.441\%\;and\;99.883\%$, respectively. And, even with smaller learning data, the SVM classifier offered better performance than the MLP classifier.

Co-Registration of Aerial Photos, ALS Data and Digital Maps Using Linear Features (선형기하보정 요소를 이용한 항공레이저측량 자료, 항공사진, 대축척 수치지도의 기하보정에 관한 연구)

  • Lee, Jae-Bin;Yu, Ki-Yun
    • Journal of Korean Society for Geospatial Information Science
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    • v.14 no.4 s.38
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    • pp.37-44
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    • 2006
  • To use surveying data obtained from different sensors and different techniques, it is a pre-requite step that register them in a common coordinate system. For this purpose, we developed methodologies to register airborne photos, ALS (Airborne Laser Scanning) data and digital maps. To achieve this, conjugate features from these data should be extracted in advance. In this study, linear features are chosen as conjugate features. Based on such a selection strategy, a simple and robust algorithm is proposed for extracting such features from ALS data. Then, to register them, observation equations are established from similarity measurements of the extracted features and the results was evaluated statistically. The results clearly demonstrate that the proposed algorithms are appropriate to register these data.

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Featured-Based Registration of Terrestrial Laser Scans with Minimum Overlap Using Photogrammetric Data

  • Renaudin, Erwan;Habib, Ayman;Kersting, Ana Paula
    • ETRI Journal
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    • v.33 no.4
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    • pp.517-527
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    • 2011
  • Currently, there is a considerable interest in 3D object reconstruction using terrestrial laser scanner (TLS) systems due to their ability to automatically generate a considerable amount of points in a very short time. To fully map an object, multiple scans are captured. The different scans need to be registered with the help of the point cloud in the overlap regions. To guarantee reliable registration, the scans should have large overlap ratio with good geometry for the estimation of the transformation parameters among these scans. The objective of this paper is to propose a registration method that relaxes/eliminates the overlap requirement through the utilization of photogrammetrically reconstructed features. More specifically, a point-based procedure, which utilizes non-conjugate points along corresponding linear features from photogrammetric and TLS data, will be used for the registration. The non-correspondence of the selected points along the linear features is compensated for by artificially modifying their weight matrices. The paper presents experimental results from simulated and real datasets to illustrate the feasibility of the proposed procedure.

Generalization of the Stream Network by the Geographic Hierarchy of Landform Data (지형자료의 계층화를 이용한 하계망 일반화)

  • Kim Nam-Shin
    • Journal of the Korean Geographical Society
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    • v.40 no.4 s.109
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    • pp.441-453
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    • 2005
  • This study aims to generalize the stream network developing algorithm of the geographic hierarchy Stream networks with hierarchy system should be spatially hierarchized in linear features. The generalization procedure of the stream networks are composed of the hierarchy of stream, selection and elimination, and algorithm. Working of stream networks is composed by the decision of direction on stream networks, ranking of stroke segments, and ordering by the strahler method, using geographic data query for controlling selection and elimination of the linear feature by scale. Improved Simoo algorithm was effective in enhancement and decreasing curvature of linear features. Resultantly, it is expected to improve generalization of features with various spatial hierarchy.

A Study on 3D Road Extraction From Three Linear Scanner

  • Yun, SHI;SHIBASAKI, Ryosuke
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.301-303
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    • 2003
  • The extraction of 3D road network from high-resolution aerial images is still one of the current challenges in digital photogrammetry and computer vision. For many years, there are many researcher groups working for this task, but unt il now, there are no papers for doing this with TLS (Three linear scanner), which has been developed for the past several years, and has very high-resolution (about 3 cm in ground resolution). In this paper, we present a methodology of road extraction from high-resolution digital imagery taken over urban areas using this modern photogrammetry’s scanner (TLS). The key features of the approach are: (1) Because of high resolution of TLS image, our extraction method is especially designed for constructing 3D road map for next -generation digital navigation map; (2) for extracting road, we use the global context of the intensity variations associated with different features of road (i.e. zebra line and center line), prior to any local edge. So extraction can become comparatively easy, because we can use different special edge detector according different features. The results achieved with our approach show that it is possible and economic to extract 3D road data from Three Linear Scanner to construct next -generation digital navigation road map.

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Face Recognition Based on Improved Fuzzy RBF Neural Network for Smar t Device

  • Lee, Eung-Joo
    • Journal of Korea Multimedia Society
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    • v.16 no.11
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    • pp.1338-1347
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    • 2013
  • Face recognition is a science of automatically identifying individuals based their unique facial features. In order to avoid overfitting and reduce the computational reduce the computational burden, a new face recognition algorithm using PCA-fisher linear discriminant (PCA-FLD) and fuzzy radial basis function neural network (RBFNN) is proposed in this paper. First, face features are extracted by the principal component analysis (PCA) method. Then, the extracted features are further processed by the Fisher's linear discriminant technique to acquire lower-dimensional discriminant patterns, the processed features will be considered as the input of the fuzzy RBFNN. As a widely applied algorithm in fuzzy RBF neural network, BP learning algorithm has the low rate of convergence, therefore, an improved learning algorithm based on Levenberg-Marquart (L-M) for fuzzy RBF neural network is introduced in this paper, which combined the Gradient Descent algorithm with the Gauss-Newton algorithm. Experimental results on the ORL face database demonstrate that the proposed algorithm has satisfactory performance and high recognition rate.

Improved Gradient Direction Assisted Linking Algorithm for Linear Feature Extraction in High Resolution Satellite Images, an Iterative Dynamic Programming Approach

  • Yang, Kai;Liew, Soo Chin;Lee, Ken Yoong;Kwoh, Leong Keong
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.408-410
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    • 2003
  • In this paper, an improved gradient direction assisted linking algorithm is proposed. This algorithm begins with initial seeds satisfying some local criteria. Then it will search along the direction provided by the initial point. A window will be generated in the gradient direction of the current point. Instead of the conventional method which only considers the value of the local salient structure, an improved mathematical model is proposed to describe the desired linear features. This model not only considers the value of the salient structure but also the direction of it. Furthermore, the linking problem under this model can be efficiently solved by dynamic programming method. This algorithm is tested for linear features detection in IKONOS images. The result demonstrates this algorithm is quite promising.

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Updating GIS Data using Modified Iterative Hough Transform Algorithm (Modified Iterative Hough Transform 알고리즘을 이용한 GIS 자료의 갱신에 대한 연구)

  • 손홍규;최종현;피문희
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2003.04a
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    • pp.429-432
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    • 2003
  • In this study, exterior orientation parameters of one image are determined using linear features of imagery and GIS data based on the Modified Iterative Hough Transform algorithm and the possibility of automatic updating GIS data is presented.

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Nonlinear Feature Extraction using Class-augmented Kernel PCA (클래스가 부가된 커널 주성분분석을 이용한 비선형 특징추출)

  • Park, Myoung-Soo;Oh, Sang-Rok
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.48 no.5
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    • pp.7-12
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    • 2011
  • In this papwer, we propose a new feature extraction method, named as Class-augmented Kernel Principal Component Analysis (CA-KPCA), which can extract nonlinear features for classification. Among the subspace method that was being widely used for feature extraction, Class-augmented Principal Component Analysis (CA-PCA) is a recently one that can extract features for a accurate classification without computational difficulties of other methods such as Linear Discriminant Analysis (LDA). However, the features extracted by CA-PCA is still restricted to be in a linear subspace of the original data space, which limites the use of this method for various problems requiring nonlinear features. To resolve this limitation, we apply a kernel trick to develop a new version of CA-PCA to extract nonlinear features, and evaluate its performance by experiments using data sets in the UCI Machine Learning Repository.

Geometric Correction of IKONOS-2 Geo-level Satellite Imagery Using LiDAR Data - Using Linear Features as Registration Primitivess (항공레이저측량 자료를 활용한 IKONOS-2 위성영상의 기하보정에 관한 연구 - 선형요소를 기하보정의 기본요소로 활용하여)

  • Lee, Jae-Bin;Kim, Yong-Min;Lee, Hyo-Seong;Yu, Ki-Yun;Kim, Yong-Il
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.25 no.3
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    • pp.183-190
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    • 2007
  • To make use of surveying data obtained from different sensors and different techniques, it is a pre-requite step that register them in a common coordinate system. For this purpose, we developed methodologies to register IKONOS-2 Satellite Imagery using LiDAR(Light Detection And Ranging) data. To achieve this, conjugate features from these data should be extracted in advance. In this study, linear features are chosen as conjugate features. Then, to register them, observation equations are established from similarity measurements of the extracted features and the results was evaluated statistically. The results clearly demonstrate that the proposed algorithms are appropriate to register these data.