• 제목/요약/키워드: Fuzzy k-means algorithm

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A Study on Optimal Fuzzy Identification by means of Hybrid Identification Algorithm

  • Park, Byoung-Jun;Park, Chun-Seong;Oh, Sung-Kwun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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    • pp.215-220
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    • 1998
  • In order to optimize fuzzy model, we use the optimal algorithm with a hybrid type in the identification of premise parameters and standard least square method in the identification of consequence parameters of a fuzzy model. The hybrid optimal identification algorithm is carried out using a genetic algorithm and improved complex method. Also, the performance index with weighting factor is proposed to achieve a balance between the insults of performance for the training and testing data. Several numerical examples are used to evaluate the performance of the proposed model.

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뉴로퍼지학습 알고리듬을 이용한 연소상태진단 (Flame Diagnosis Using Neuro-Fuzzy Learning Algorithm)

  • 이태영;김성환;이상룡
    • 대한기계학회논문집A
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    • 제26권4호
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    • pp.587-595
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    • 2002
  • Recent trend changes a criterion for evaluation of humors that environmental problems are raised as a global issue. Burners with higher thermal efficiency and lower oxygen in the exhaust gas, evaluated better. To comply with environmental regulations, burners must satisfy the NO/sub x/ and CO regulation. Consequently, 'good burner'means one whose thermal efficiency is high under the constraint of NO/sub x/ and CO consistency. To make existing burner satisfy recent criterion, it is highly recommended to develop a feedback control scheme whose output is the consistency of NO/sub x/ and CO. This paper describes the development of a real time flame diagnosis technique that evaluate and diagnose the combustion states, such as consistency of components in exhaust gas, stability of flame in the quantitative sense. In this paper, it was proposed on the flame diagnosis technique of burner using Neuro-Fuzzy algorithm. This study focuses on the relation of the color of the flame and the state of combustion. Neuro-Fuzzy loaming algorithm is used in obtaining the fuzzy membership function and rules. Using the constructed inference algorithm, the amount of NO/sub x/ and CO of the combustion gas was successfully inferred.

HCM을 이용한 퍼지 모델의 On-Line 동정 (On-line Identification of fuzzy model using HCM algorithm)

  • 박호성;박병준;오성권
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 G
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    • pp.2929-2931
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    • 1999
  • In this paper, an adaptive fuzzy inference and HCM(Hard C-Means) clustering method are used for on-line fuzzy modeling of nonlinear and complex system. Here HCM clustering method is utilized for determining the initial parameter of membership function of fuzzy premise rules and also avoiding overflow phenomenon during the identification of consequence parameters. To obtain the on-line model structure of fuzzy systems. we use the recursive least square method for the consequent parameter identification. And the proposed on-line identification algorithm is carried out and is evaluated for sewage treatment process system.

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FUZZY IDENTIFICATION BY MEANS OF AUTO-TUNING ALGORITHM AND WEIGHTING FACTOR

  • Park, Chun-Seong;Oh, Sung-Kwun;Ahn, Tae-Chon;Pedrycz, Witold
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 The Third Asian Fuzzy Systems Symposium
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    • pp.701-706
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    • 1998
  • A design method of rule -based fuzzy modeling is presented for the model identification of complex and nonlinear systems. The proposed rule-based fuzzy modeling implements system structure and parameter identification in the efficient form of " IF..., THEN,," statements. using the theories of optimization and linguistic fuzzy implication rules. The improved complex method, which is a powerful auto-tuning algorithm, is used for tuning of parameters of the premise membership functions in consideration of the overall structure of fuzzy rules. The optimized objective function, including the weighting factors, is auto-tuned for better performance of fuzzy model using training data and testing data. According to the adjustment of each weighting factor of training and testing data, we can construct the optimal fuzzy model from the objective function. The least square method is utilized for the identification of optimum consequence parameters. Gas furance and a sewage treatment proce s are used to evaluate the performance of the proposed rule-based fuzzy modeling.

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대학 강의평가에서 문항 추출에 관한 연구 (A Study on Effective Selection of University Lecture Evaluation)

  • 황세명;김인택
    • 공학교육연구
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    • 제8권1호
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    • pp.31-45
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    • 2005
  • 본 논문에서는, 강의 평가에 필요한 설문을 효과적이며 체계적으로 얻기 위한, 대표 문항 추출 방법을 비교하였다. 비교에 사용한 방법은 요인분석(Factor Analysis: FA), FCM(Fuzzy c-Means) 알고리즘과 군집분석(Cluster Analysis : CA) 등으로 이러한 방법들을 사용하여 고려할 수 있는 다양한 형태의 많은 문항들로부터 적은 수의 문항을 추출한다. 추출된 문항은 많은 수의 문항들이 형성하는 클러스터의 대표 문항을 이루고 있다. 이를 위해 여러 개의 설문지로부터 얻은 120 문항의 강의 평가서를 명지대학교 외 3 개 대학교 646명의 학생들에게 평가를 실시하여 데이터를 얻었는데 학생들은 주어진 문항에 대하여 "매우 그렇다", "그렇다", "보통이다", "그렇지 않다", "매우 그렇지 않다", 그리고 "해당 없다"까지의 6등급으로 응답하였다. 각 문항에 대한 학생들의 응답 성향을 분석하여 약 25문항을 추출하였다. 실험 결과 본 논문에서 비교 분석한 요인분석, FCM알고리즘과 군집분석 등의 기법은 매우 유사한 설문을 추출할 수 있었다.

Colorectal Cancer Staging Using Three Clustering Methods Based on Preoperative Clinical Findings

  • Pourahmad, Saeedeh;Pourhashemi, Soudabeh;Mohammadianpanah, Mohammad
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권2호
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    • pp.823-827
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    • 2016
  • Determination of the colorectal cancer stage is possible only after surgery based on pathology results. However, sometimes this may prove impossible. The aim of the present study was to determine colorectal cancer stage using three clustering methods based on preoperative clinical findings. All patients referred to the Colorectal Research Center of Shiraz University of Medical Sciences for colorectal cancer surgery during 2006 to 2014 were enrolled in the study. Accordingly, 117 cases participated. Three clustering algorithms were utilized including k-means, hierarchical and fuzzy c-means clustering methods. External validity measures such as sensitivity, specificity and accuracy were used for evaluation of the methods. The results revealed maximum accuracy and sensitivity values for the hierarchical and a maximum specificity value for the fuzzy c-means clustering methods. Furthermore, according to the internal validity measures for the present data set, the optimal number of clusters was two (silhouette coefficient) and the fuzzy c-means algorithm was more appropriate than the k-means clustering approach by increasing the number of clusters.

잡음 구분에 의한 지능형 기동표적 추적기법 (Intelligent Maneuvering Target Tracking Based on Noise Separation)

  • 손현승;박진배;주영훈
    • 한국지능시스템학회논문지
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    • 제21권4호
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    • pp.469-474
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    • 2011
  • 본 논문에서는 기동표적의 위치 오차값 보상 기법을 이용한 지능형 기동표적 추적 기법을 제안한다. 기동표적의 관측값과 예상위치와의 차이를 가속도와 순수 잡음으로 분리한다. 최적의 수준으로 가속도를 추출하기 위하여 K-means 클러스터링 기법과 TS 퍼지 시스템을 이용한다. K-means 클러스터링에 의해 분리된 가속도와 잡음에 대한 소속함수를 설정하고 퍼지 모델화하여 기동표적의 특성을 파악한다. 계산상의 오차를 보상하기 위하여 분리된 가속도와 잡음은 추적 알고리즘의 계산과정에 적절히 이용된다. 추정값 계산시, 가속도를 분리 하므로써 필터링 과정은 표적의 비선형 기동을 선형기동으로 인식하여 칼만필터의 성능을 유지시킨다. 기동표적의 비선형성에 대한 오차는 추정된 가속도를 통해 보상된다. 제안된 시스템의 소속함수에 사용되는 파라미터값을 조종하여 상황에 따라 적응성과 강인성을 향상시킨다. 제안된 시스템은 실시간 추적이 가능하도록 구성하였으며, 몇 가지 예를 통하여 본 논문에서 제안한 방법의 우수성을 증명한다.

Nucleus Recognition of Uterine Cervical Pap-Smears using FCM Clustering Algorithm

  • Kim, Kwang-Baek
    • Journal of information and communication convergence engineering
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    • 제6권1호
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    • pp.94-99
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    • 2008
  • Segmentation for the region of nucleus in the image of uterine cervical cytodiagnosis is known as the most difficult and important part in the automatic cervical cancer recognition system. In this paper, the region of nucleus is extracted from an image of uterine cervical cytodiagnosis using the HSI model. The characteristics of the nucleus are extracted from the analysis of morphemetric features, densitometric features, colormetric features, and textural features based on the detected region of nucleus area. The classification criterion of a nucleus is defined according to the standard categories of the Bethesda system. The fuzzy C-means clustering algorithm is employed to the extracted nucleus and the results show that the proposed method is efficient in nucleus recognition and uterine cervical Pap-Smears extraction.

성장곡선을 이용한 퍼지군집분석 기법의 연구 (A Study of the Fuzzy Clustering Algorithm using a Growth Curve Model)

  • 김응환;이석훈
    • 응용통계연구
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    • 제14권2호
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    • pp.439-448
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    • 2001
  • 본 연구는 시간자료(Longitudinal data)의 분석을 위하여 Fuzzy k-means 군집분석 방법을 확장한 알고리즘을 제안한다. 이 논문에서 제안하는 군집분석방법은 각각의 개체에 대응하는 성장곡선에 Fuzzy k-means 군집분석의 알고리즘을 결합하는 것을 핵심아이디어로한다. 분석결과는 생성된 군집을 성장곡선모형으로 표현할 수 있고 또한 추정된 모형의 식을 활용하여 새로운 개체를 분류도 할수 있음을 보인다. 그리고 이 군집분석방법은 아직 자라지 않은 나이 어린 개체가 미래에 어느 군집에 속할 것인가 하는 분류와 함께 이 개체의 향후 성장상태를 예측을 하는 데에도 적용이 가능하다. 제안된 알고리즘을 원숭이(macaque)의 상악동(maxillary sinus)의 자료에 적용한 실례로 보인다.

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Identification of Fuzzy Systems by means of the Extended GMDH Algorithm

  • Park, Chun-Seong;Park, Jae-Ho;Oh, Sung-Kwun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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    • pp.254-259
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    • 1998
  • A new design methology is proposed to identify the structure and parameters of fuzzy model using PNN and a fuzzy inference method. The PNN is the extended structure of the GMDH(Group Method of Data Handling), and uses several types of polynomials such as linear, quadratic and cubic besides the biquadratic polynomial used in the GMDH. The FPNN(Fuzzy Polynomial Neural Networks) algorithm uses PNN(Polynomial Neural networks) structure and a fuzzy inference method. In the fuzzy inference method, the simplified and regression polynomial inference methods are used. Here a regression polynomial inference is based on consequence of fuzzy rules with a polynomial equations such as linear, quadratic and cubic equation. Each node of the FPNN is defined as fuzzy rules and its structure is a kind of neuro-fuzzy architecture. In this paper, we will consider a model that combines the advantage of both FPNN and PNN. Also we use the training and testing data set to obtain a balance between the approximation and generalization of process model. Several numerical examples are used to evaluate the performance of the our proposed model.

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