• 제목/요약/키워드: Classification of Scheme

검색결과 837건 처리시간 0.031초

모의결함을 갖는 고체절연재에서 발생하는 부분방전 및 패턴분류 (Classification of PD Signals Generated in Solid Dielectrics by Neural Networks)

  • 박성희;이강원;박재열;강성화;임기조
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 C
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    • pp.1876-1878
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    • 2003
  • The recognition of PD(Partial Discharge) phenomenon is useful for classification of defects. The distribution of stochastic parameters which consisted of those PD pulses data and pulses train can show discriminable characteristics of PD sources. But it is not sufficient to discriminate among to PD sources. In this paper, we suggests that classification method of PD source by NN(Neural Networks) are good tools for differentiate of those. The learning scheme of NN is (Back Propagation learning algorithm(BP).

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Ultrasonic NDE Classifications with the Gradient Descent Method and Synthetic Aperture Focusing Technique

  • Kim, Dae-Won
    • 비파괴검사학회지
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    • 제25권3호
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    • pp.189-200
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    • 2005
  • Ultrasonic inspection methods are widely used for detecting flaws in materials. One of the more popular methods involves the extraction of an appropriate set of features followed by the use of a neural network for the classification of the signals in the feature space. This paper describes an approach which uses LMS method to determine the coordinates of the ultrasonic probe followed by the use of SAFT to estimate the location of the ultrasonic reflector The method is employed for classifying NDE signals from the steam generator tubes in a nuclear power plant. The classification results using this scheme for the ultrasonic signals from cracks and deposits within steam generator tubes are presented.

진공함침에 따른 견인전동기 고정자 코일의 부분방전 분포 해석 및 분류 (Analysis and Classification of PD Distribution for VPI Stator coil of Traction motor)

  • 박성희;강성화;임기조;장동욱;박현준
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 C
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    • pp.1982-1984
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    • 2004
  • Stator coil of rotating machinery has shown different characteristics according to impregnated with coil or not. And this is major determinant of equipment's life. In this paper, PD characteristics is studied as a classification scheme between two specimens. Processing of the coil impregnation is very important thing because that influences on thermal and electrical characteristics of the coil. And then PD is occurring at the coil and causing insulation degradation. For processing statistical processing, PD data acquired from PD detector using PDASDA(partial discharge acquisition, storage and display system). And also these statistical distribution and parameter are applied to classify PD sources by neural networks. As a result of, Neural Networks have a good discrimination rate for classification PD sources.

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필기체 한글의 오프라인 인식을 위한 효과적인 두 단계 패턴 정합 방법 (Efficient two-step pattern matching method for off-line recognition of handwritten Hangul)

  • 박정선;이성환
    • 전자공학회논문지B
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    • 제31B권4호
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    • pp.1-8
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    • 1994
  • In this paper, we propose an efficient two-step pattern matching method which promises shape distortion-tolerant recognition of handwritten of handwritten Hangul syllables. In the first step, nonlinear shape normalization is carried out to compensate for global shape distortions in handwritten characters, then a preliminary classification based on simple pattern matching is performed. In the next step, nonlinear pattern matching which achieves best matching between input and reference pattern is carried out to compensate for local shape distortions, then detailed classification which determines the final result of classification is performed. As the performance of recognition systems based on pattern matching methods is greatly effected by the quality of reference patterns. we construct reference patterns by combining the proposed nonlinear pattern matching method with a well-known averaging techniques. Experimental results reveal that recognition performance is greatly improved by the proposed two-step pattern matching method and the reference pattern construction scheme.

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부분방전원의 분류에 있어서 BP와 SOM의 비교 (Comparison of BP and SOM as a Classification of PD Source)

  • 박성희;강성화;임기조
    • 한국전기전자재료학회논문지
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    • 제17권9호
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    • pp.1006-1012
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    • 2004
  • In this paper, neural networks is studied to apply as a PD source classification in XLPE power cable specimen. Two learning schemes are used to classification; BP(Back propagation algorithm), SOM(self organized map - kohonen network). As a PD source, using treeing discharge sources in the specimen, three defected models are made. And these data making use of a computer-aided discharge analyser, statistical and other discharge parameters is calculated to discrimination between different models of discharge sources. And a]so these distribution characteristics are applied to classify PD sources by two scheme of the neural networks. In conclusion, recognition efficiency of BP is superior to SOM.

Category Factor Based Feature Selection for Document Classification

  • Kang Yun-Hee
    • International Journal of Contents
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    • 제1권2호
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    • pp.26-30
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    • 2005
  • According to the fast growth of information on the Internet, it is becoming increasingly difficult to find and organize useful information. To reduce information overload, it needs to exploit automatic text classification for handling enormous documents. Support Vector Machine (SVM) is a model that is calculated as a weighted sum of kernel function outputs. This paper describes a document classifier for web documents in the fields of Information Technology and uses SVM to learn a model, which is constructed from the training sets and its representative terms. The basic idea is to exploit the representative terms meaning distribution in coherent thematic texts of each category by simple statistics methods. Vector-space model is applied to represent documents in the categories by using feature selection scheme based on TFiDF. We apply a category factor which represents effects in category of any term to the feature selection. Experiments show the results of categorization and the correlation of vector length.

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Adaptive Fuzzy Inference Algorithm for Shape Classification

  • Kim, Yoon-Ho;Ryu, Kwang-Ryol
    • 한국정보통신학회논문지
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    • 제4권3호
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    • pp.611-618
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    • 2000
  • This paper presents a shape classification method of dynamic image based on adaptive fuzzy inference. It describes the design scheme of fuzzy inference algorithm which makes it suitable for low speed systems such as conveyor, uninhabited transportation. In the first Discrete Wavelet Transform(DWT) is utilized to extract the motion vector in a sequential images. This approach provides a mechanism to simple but robust information which is desirable when dealing with an unknown environment. By using feature parameters of moving object, fuzzy if - then rule which can be able to adapt the variation of circumstances is devised. Then applying the implication function, shape classification processes are performed. Experimental results are presented to testify the performance and applicability of the proposed algorithm.

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우리나라 수산업의 산업적 분류에 대한 연구 (A Study on Industrial Classification of Fisheries in Korea)

  • 김삼곤
    • 수산해양교육연구
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    • 제20권1호
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    • pp.23-35
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    • 2008
  • The purposes of this study are to analyze problems in industrial classification of fisheries in Korea and to suggest future directions. Based on a thorough review of relevant literature, the study proposes a five-level scheme for classifying fisheries. The highest level should be the fisheries industry, and the next highest level ought to be fisheries. The medium level should include fishing, aquaculture, and fishery service industries. At the fourth level, fishing is to be further divided into sea fishery and inland fishery, aquaculture into sea-surface aquaculture and inland aquaculture, and fishery service industries into integrated fishery service and fishery distribution service. The lowest level is the most detailed. At this level, sea fishery is split into deep sea fishery, offshore fishery, and coastal fishery; sea-surface aquaculture consists of sea aquaculture, seed production aquaculture, and food organism aquaculture; integrated fishery service is further classified into fishery-related service and fishery information service.

A Resetting Scheme for Process Parameters using the Mahalanobis-Taguchi System

  • Park, Chang-Soon
    • 응용통계연구
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    • 제25권4호
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    • pp.589-603
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    • 2012
  • Mahalanobis-Taguchi system(MTS) is a statistical tool for classifying the normal group and abnormal group in multivariate data structures. In addition to the classification itself, the MTS uses a method for selecting variables useful for the classification. This method can be used efficiently especially when the abnormal group data are scattered without a specific directionality. When the feedback adjustment procedure through the measurements of the process output for controlling process input variables is not practically possible, the reset procedure can be an alternative one. This article proposes a reset procedure using the MTS. Moreover, a method for identifying input variables to reset is also proposed by the use of the contribution. The identification of the root-cause parameters using the existing dimension-reduced contribution tends to be difficult due to the variety of correlation relationships of multivariate data structures. However, it became possible to provide an improved decision when used together with the location-centered contribution and the individual-parameter contribution.

Kano 모형에 기반한 소비자 요구사항 분류: 퍼지 접근방법 (Fuzzy KANO Model: Fuzzy Set-Based Classification of Customer Requirements)

  • 임정훈;민대기;김광재
    • 품질경영학회지
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    • 제31권3호
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    • pp.98-113
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    • 2003
  • Kano model distinguishes three types of customer requirements, namely, one-dimensional quality, must-be quality, and attractive quality. There are a few methods for classifying a given customer requirement into one of the Kano's quality elements. However, the existing methods have a common limitation in that they are based on Kano evaluation table. Kano evaluation table is not always effective for the classification task, and suffers from a significant information loss. This paper proposes an alternative to Kano's evaluation table and a new classification scheme based on fuzzy set concept. The proposed method is illustrated using a case study on the ADSL service.