• Title/Summary/Keyword: Feature space

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Document Clustering Technique by K-means Algorithm and PCA (주성분 분석과 k 평균 알고리즘을 이용한 문서군집 방법)

  • Kim, Woosaeng;Kim, Sooyoung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.3
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    • pp.625-630
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    • 2014
  • The amount of information is increasing rapidly with the development of the internet and the computer. Since these enormous information is managed by the document forms, it is necessary to search and process them efficiently. The document clustering technique which clusters the related documents through the similarity between the documents help to classify, search, and process the large amount of documents automatically. This paper proposes a method to find the initial seed points through principal component analysis when the documents represented by vectors in the feature vector space are clustered by K-means algorithm in order to increase clustering performance. The experiment shows that our method has a better performance than the traditional K-means algorithm.

A Study of Baek-je Relic with Modern So-ban Design - Focused on Gold Chignon Ornaments - (백제문양을 이용한 현대 소반 Design 연구 -뒤꽃이를 중심으로-)

  • Ra, Soo-Youn;Kim, Yun-Hee;Kim, Gun-Soo
    • Journal of the Korea Furniture Society
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    • v.18 no.3
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    • pp.195-204
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    • 2007
  • The house method of today is the house form which is composed inside the space where it is unified in social change. Also the life method from left was exchanged with stand-up meal and it became simplification and also the form of So-ban changed in the life method which is controlled. If the ship construction trillion So-ban was the furniture which is used with putting first and today the So-ban with variation of form or the material changed with entirely different role. The So-ban of today was used in the pattern element which is form freely to appear, dual anger there is a possibility of knowing the fact that it is turning out with the So-ban which expresses a geometric pattern with the present-day sense. Today of the So-ban it will pattern it will rightly use Beak-je, the feature person who is the possibility this pattern showing It is soft with the sharp, soft beauty of curved line and rectilinear which is refined, omission and emphasizing which are bold today It applied in So-ban design.

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An Elliptical Basis Function Network for Classification of Remote-Sensing Images

  • Luo, Jian-Cheng;Chen, Qiu-Xiao;Zheng, Jiang;Leung, Yee;Ma, Jiang-Hong
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1326-1328
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    • 2003
  • An elliptical basis function (EBF) network is proposed in this study for the classification of remotely sensed images. Though similar in structure, the EBF network differs from the well-known radial basis function (RBF) network by incorporating full covariance matrices and uses the expectation-maximization (EM) algorithm to estimate the basis functions. Since remotely sensed data often take on mixture -density distributions in the feature space, the proposed network not only possesses the advantage of the RBF mechanism but also utilizes the EM algorithm to compute the maximum likelihood estimates of the mean vectors and covariance matrices of a Gaussian mixture distribution in the training phase. Experimental results show that the EM-based EBF network is faster in training, more accurate, and simpler in structure.

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Hybrid Fuzzy Least Squares Support Vector Machine Regression for Crisp Input and Fuzzy Output

  • Shim, Joo-Yong;Seok, Kyung-Ha;Hwang, Chang-Ha
    • Communications for Statistical Applications and Methods
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    • v.17 no.2
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    • pp.141-151
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    • 2010
  • Hybrid fuzzy regression analysis is used for integrating randomness and fuzziness into a regression model. Least squares support vector machine(LS-SVM) has been very successful in pattern recognition and function estimation problems for crisp data. This paper proposes a new method to evaluate hybrid fuzzy linear and nonlinear regression models with crisp inputs and fuzzy output using weighted fuzzy arithmetic(WFA) and LS-SVM. LS-SVM allows us to perform fuzzy nonlinear regression analysis by constructing a fuzzy linear regression function in a high dimensional feature space. The proposed method is not computationally expensive since its solution is obtained from a simple linear equation system. In particular, this method is a very attractive approach to modeling nonlinear data, and is nonparametric method in the sense that we do not have to assume the underlying model function for fuzzy nonlinear regression model with crisp inputs and fuzzy output. Experimental results are then presented which indicate the performance of this method.

The effects of scanning position on evaluation of cerebral atrophy level: assessed by item response theory

  • Mahsin, Md;Zhao, Yinshan
    • Communications for Statistical Applications and Methods
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    • v.23 no.6
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    • pp.531-541
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    • 2016
  • Cerebral atrophy affects the brain and is a common feature of patients with mild cognitive impairment or Alzheimer's diseases. It is evaluated by the radiologist or reader based on patient's history, age and the space between the brain and the skull as indicated by magnetic resonance (MR) images. A total of 70 patients were scanned in the supine and prone positions before three radiologist assessed their atrophy level. This study examined the radiologist's assessment of the cerebral atrophy level using a graded response model of item response theory (IRT). A graded response model (GRM) is fitted to our data and then item-fit and person-fit statistics are evaluated to assess the fitted model. Our analysis found that the cerebral atrophy level is better discriminated by readers in the prone position because all item slopes were greater than 2 at this position, versus the supine position where all the slope parameters were less than 1. However, the thresholds are very similar for the first reader and are quite different for the second and third readers because the scanning position affects readers differently as the category threshold estimates vary considerably between the readers..

Optimal Estimation of Rock Mass Properties Using Genetic Algorithm (유전알고리즘을 이용한 암반 물성의 최적 평가에 관한 연구)

  • Hong Changwoo;Jeon Seokwon
    • Tunnel and Underground Space
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    • v.15 no.2 s.55
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    • pp.129-136
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    • 2005
  • This paper describes the implementation of rock mass rating evaluation based on genetic algorithm(GA) and conditional simulation technique to estimate RMR in the area without sufficient borehole data RMR were estimated by GA and conditional simulation technique with reflecting distribution feature and spatial correlation. And RMR determined by GA were compared with the results from kriging. Through the analysis of the results from 30 simulations, the uncertainty of estimation could be quantified.

Classification of Normal/Abnormal Conditions for Small Reciprocating Compressors using Wavelet Transform and Artificial Neural Network (웨이브렛변환과 인공신경망 기법을 이용한 소형 왕복동 압축기의 상태 분류)

  • Lim, Dong-Soo;An, Jin-Long;Yang, Bo-Suk;An, Byung-Ha
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.11a
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    • pp.796-801
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    • 2000
  • The monitoring and diagnostics of the rotating machinery have been received considerable attention for many years. The objectives are to classify the machinery condition and to find out the cause of abnormal condition. This paper describes a signal classification method for diagnosing the rotating machinery using the artificial neural network and the wavelet transform. In order to extract salient features, the wavelet transform are used from primary noise signals. Since the wavelet transform decomposes raw time-waveform signals into two respective parts in the time space and frequency domain, more and better features can be obtained easier than time-waveform analysis. In the training phase for classification, self-organizing feature map(SOFM) and learning vector quantization(LVQ) are applied, and the accuracies of them are compared with each other. This paper is focused on the development of an advanced signal classifier to automatise the vibration signal pattern recognition. This method is verified by small reciprocating compressors, for refrigerator and normal and abnormal conditions are classified with high flexibility and reliability.

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A novel, reversible, Chinese text information hiding scheme based on lookalike traditional and simplified Chinese characters

  • Feng, Bin;Wang, Zhi-Hui;Wang, Duo;Chang, Ching-Yun;Li, Ming-Chu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.1
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    • pp.269-281
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    • 2014
  • Compared to hiding information into digital image, hiding information into digital text file requires less storage space and smaller bandwidth for data transmission, and it has obvious universality and extensiveness. However, text files have low redundancy, so it is more difficult to hide information in text files. To overcome this difficulty, Wang et al. proposed a reversible information hiding scheme using left-right and up-down representations of Chinese characters, but, when the scheme is implemented, it does not provide good visual steganographic effectiveness, and the embedding and extracting processes are too complicated to be done with reasonable effort and cost. We observed that a lot of traditional and simplified Chinese characters look somewhat the same (also called lookalike), so we utilize this feature to propose a novel information hiding scheme for hiding secret data in lookalike Chinese characters. Comparing to Wang et al.'s scheme, the proposed scheme simplifies the embedding and extracting procedures significantly and improves the effectiveness of visual steganographic images. The experimental results demonstrated the advantages of our proposed scheme.

Improved Tooth Detection Method for using Morphological Characteristic (형태학적 특징을 이용한 향상된 치아 검출 방법)

  • Na, Sung Dae;Lee, Gihyoun;Lee, Jyung Hyun;Kim, Myoung Nam
    • Journal of Korea Multimedia Society
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    • v.17 no.10
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    • pp.1171-1181
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    • 2014
  • In this paper, we propose improved methods which are image conversion and extraction method of watershed seed using morphological characteristic of teeth on complement image. Conventional tooth segmentation methods are occurred low detection ratio at molar region and over, overlap segmentation owing to specular reflection and morphological feature of molars. Therefore, in order to solve the problems of the conventional methods, we propose the image conversion method and improved extraction method of watershed seed. First, the image conversion method is performed using RGB, HSI space of tooth image for to extract boundary and seed of watershed efficiently. Second, watershed seed is reconstructed using morphological characteristic of teeth. Last, individual tooth segmentation is performed using proposed seed of watershed by watershed algorithm. Therefore, as a result of comparison with marker controlled watershed algorithm and the proposed method, we confirmed higher detection ratio and accuracy than marker controlled watershed algorithm.

Facial Impression Classification for Sasang Constitution Diagnosis (사상체질 진단을 위한 얼굴인상 분류)

  • Jang, Kyung-Shik
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.1
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    • pp.196-204
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    • 2008
  • In this paper, we propose an efficient method to classify human facial impression using frontal face image. The features that represent the shape of eye, jaw and face are used. The proposed method employs PCA, LDA and SVM in series. PCA is used to project the feature space to a low dimensional subspace. LDA produces well separated classes in a low dimensional subspace even under severe variation. This results in good discriminating power for classification. SVM is used to classify the data. Human face has been classified for 8 facial impressions. The experiments have been performed for many face images, and show encouraging result.