• 제목/요약/키워드: Self-organizing map

검색결과 424건 처리시간 0.033초

2 단 Self-Organizing Feature Map 을 사용한 변환 영역 영상의 벡터 양자화 (Image VQ Using Two-Stage Self-Organizing Feature Map in the Transform Domain)

  • 이동학;김영환
    • 전자공학회논문지B
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    • 제32B권3호
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    • pp.57-65
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    • 1995
  • This paper presents a new classified vector quantization (VQ) technique using a neural network model in the transform domain. Prior to designing a codebook, the proposed approach extracts class features from a set of images using self-organizing feature map (SOFM) that has the pattern recognition characteristics and the same as VQ objective. Since we extract the class features from the training images unlike previous approaches, the reconstructed image quality is improved. Moreover, exploiting the adaptivity of the neural network model makes our approach be easily applied to designing a new vector quantizer when the processed image characteristics are changed. After the generalized BFOS algorithm allocates the given bits to each class, codebooks of each class are also generated using SOFM for the maximal reconstructed image quality. In experimental results using monochromatic images, we obtained a good visual quality in the reconstructed image. Also, PSNR is comparable to that of other classified VQ technique and is higher than that of JPEG baseline system.

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코호넨 자기조직화함수를 이용한 홍수위 예측 (Flood Stage Forecasting using Kohonen Self-Organizing Map)

  • 김성원;김형수
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2007년도 학술발표회 논문집
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    • pp.1427-1431
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    • 2007
  • In this study, the new methodology which combines Kohonen self-organizing map(KSOM) neural networks model and the conventional neural networks models such as feedforward neural networks model and generalized neural networks model is introduced to forecast flood stage in Nakdong river, Republic of Korea. It is possible to train without output data in KSOM neural networks model. KSOM neural networks model is used to classify the input data before it combines with the conventional neural networks model. Four types of models such as SOM-FFNNM-BP, SOM-GRNNM-GA, FFNNM-BP, and GRNNM-GA are used to train and test performances respectively. From the statistical analysis for training and testing performances, SOM-GRNNM-GA shows the best results compared with the other models such as SOM-FFNNM-BP, FFNNM-BP, and GRNNM-GA and FFNNM-BP shows vice-versa. From this study, we can suggest the new methodology to forecast flood stage and construct flood warning system in river basin.

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A Method for Producing Animation as a Series of Backward-Projected Patterns in a Self-Organizing Map

  • Wakuya, Hiroshi;Takahama, Eishi;Itoh, Hideaki;Fukumoto, Hisao;Furukawa, Tatsuya
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2012년도 춘계 종합학술대회 논문집
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    • pp.195-196
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    • 2012
  • A self-organizing map (SOM) can be seen as an analytical tool to discover some underlying rules in the given data set. Based on such distinctive nature called topology-preserving projection, a new method for generating intermediate patterns was proposed. Then, following to this method, producing animation as a series of backward-projected patterns just like a flip book is tried in this article.

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자기조직화지도를 이용한 직선 추출 알고리즘 (A Straight-Line Detecting Algorithm Using a Self-Organizing Map)

  • 이문규
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 2002년도 춘계공동학술대회
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    • pp.886-893
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    • 2002
  • The standard Hough transform has been dominantly used to detect straight lines in an image. However, massive storage requirement and low precision in estimating line parameters due to the quantization of parameter space are the major drawbacks of the Hough transform technique. In this paper, to overcome the drawbacks, an iterative algorithm based on a self-organizing map is presented. The self-organizing map can be adaptively learned such that image points are clustered by prominent lines. Through the procedure of the algorithm, a set of lines are sequentially detected one at a time. Computational results for synthetically generated images are given. The promise of the algorithm is also demonstrated with its application to two natural images of inserts.

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데이터 마이닝 기법의 기업도산예측 실증분석 (A Study of Data Mining Techniques in Bankruptcy Prediction)

  • Lee, Kidong
    • 한국경영과학회지
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    • 제28권2호
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    • pp.105-127
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    • 2003
  • In this paper, four different data mining techniques, two neural networks and two statistical modeling techniques, are compared in terms of prediction accuracy in the context of bankruptcy prediction. In business setting, how to accurately detect the condition of a firm has been an important event in the literature. In neural networks, Backpropagation (BP) network and the Kohonen self-organizing feature map, are selected and compared each other while in statistical modeling techniques, discriminant analysis and logistic regression are also performed to provide performance benchmarks for the neural network experiment. The findings suggest that the BP network is a better choice among the data mining tools compared. This paper also identified some distinctive characteristics of Kohonen self-organizing feature map.

An Optimal Clustering using Hybrid Self Organizing Map

  • Jun, Sung-Hae
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제6권1호
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    • pp.10-14
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    • 2006
  • Many clustering methods have been studied. For the most part of these methods may be needed to determine the number of clusters. But, there are few methods for determining the number of population clusters objectively. It is difficult to determine the cluster size. In general, the number of clusters is decided by subjectively prior knowledge. Because the results of clustering depend on the number of clusters, it must be determined seriously. In this paper, we propose an efficient method for determining the number of clusters using hybrid' self organizing map and new criterion for evaluating the clustering result. In the experiment, we verify our model to compare other clustering methods using the data sets from UCI machine learning repository.

SOFM(Self-Organizing Feature Map)형식의 Travelling Salesman 문제 해석 알고리즘 (Self Organizing Feature Map Type Neural Computation Algorithm for Travelling Salesman Problem)

  • 석진욱;조성원;최경삼
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 하계학술대회 논문집 B
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    • pp.983-985
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    • 1995
  • In this paper, we propose a Self Organizing Feature Map (SOFM) Type Neural Computation Algorithm for the Travelling Salesman Problem(TSP). The actual best solution to the TSP problem is computatinally very hard. The reason is that it has many local minim points. Until now, in neural computation field, Hopield-Tank type algorithm is widely used for the TSP. SOFM and Elastic Net algorithm are other attempts for the TSP. In order to apply SOFM type neural computation algorithms to the TSP, the object function forms a euclidean norm between two vectors. We propose a Largrangian for the above request, and induce a learning equation. Experimental results represent that feasible solutions would be taken with the proposed algorithm.

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Scanning Acoustic Tomograph 방식을 이용한 지능형 반도체 평가 알고리즘 (The Intelligence Algorithm of Semiconductor Package Evaluation by using Scanning Acoustic Tomograph)

  • 김재열;김창현;송경석;양동조;장종훈
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2005년도 춘계학술대회 논문집
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    • pp.91-96
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    • 2005
  • In this study, researchers developed the estimative algorithm for artificial defects in semiconductor packages and performed it by pattern recognition technology. For this purpose, the estimative algorithm was included that researchers made software with MATLAB. The software consists of some procedures including ultrasonic image acquisition, equalization filtering, Self-Organizing Map and Backpropagation Neural Network. Self-Organizing Map and Backpropagation Neural Network are belong to methods of Neural Networks. And the pattern recognition technology has applied to classify three kinds of detective patterns in semiconductor packages: Crack, Delamination and Normal. According to the results, we were confirmed that estimative algorithm was provided the recognition rates of $75.7\%$ (for Crack) and $83_4\%$ (for Delamination) and $87.2\%$ (for Normal).

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SDN 환경에서 자기조직화지도 신경망을 이용한 분산 컨트롤러 (Distributed controllers using a Self-Organizing Map Neural Network in SDN environment)

  • 유승언;김민우;이병준;김경태;윤희용
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2019년도 제59차 동계학술대회논문집 27권1호
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    • pp.47-48
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    • 2019
  • 본 논문에서는 신경망의 일종인 자기조직화지도(Self Organizing Map)을 이용하여 컨트롤러의 순서를 정하는 모델을 제안하였다. 자기조직화지도는 자율 학습에 의한 클러스터링을 수행하는 알고리즘으로써 컨트롤러에 가중치를 부여하고 컨트롤러 간 거리를 계산하여 효율적인 컨트롤러 선택을 목표로 한다.

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주성분 자기조직화 지도 PC-SOM (Principal Components Self-Organizing Map PC-SOM)

  • 허명회
    • 응용통계연구
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    • 제16권2호
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    • pp.321-333
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    • 2003
  • 자기조직화 지도(SOM)은 T. 코호넨의 주도하에 개발된 비지도 학습 신경망 모형이다. 그 동안 패턴인식과 문서검색 분야에 주로 응용되어 왔기 때문에 통계학 분야에서는 덜 알려졌으나, 최근 K-평균 군집화에 대한 대안적 데이터 마이닝 기법으로 활용되기 시작하였다. 본 연구에서는 SOM의 한 버전인 PC-SOM(주성분 자기조직화 지도)을 제안하고 활용 예를 제시하고자 한다. PC-SOM은 1차원적 SOM 알고리즘을 반복 수행하여 2차원, 3차원 등의 SOM을 얻는 방법이기 때문에 기존 SOM과는 달리 사전 Map의 크기를 확정할 필요가 없다. 또한, 기존 SOM에 비하여 향상된 시각화를 가능하게 한다.