• Journal of the Korean Society for Precision Engineering
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• v.15 no.2
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• pp.75-80
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• 1998

Process information is known to have the continuous distribution in many manufacturing processes. Generalized p-chart has been developed for controlling processes by classifying the information characteristics into several groups. But it is improper to describe continuous processes with the classified process informal ion, which is based on the classical set concept. Fuzzy control chart, has been developed for the control of linguistic data, but it is also based on the dichotomous notion of classical set theory. In this paper, fuzzy sampling method is studied in order to process the uncertain data properly. The method is incorporated with the fuzzy control chart. Statistical characteristics of the fuzzy representative value are utilized to device the fuzzy-statistical control chart. The fuzzy-statistical control chart is compared with the generalized p-chart and both the sensitivity to the process information distribution change pared robustiness against the noise on the process information of the fuzzy-statistical control chart are shown to be superior.

• Journal of the Korean Institute of Intelligent Systems
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• v.7 no.2
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• pp.66-69
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• 1997

In this paper a fuzzy similarity measure is proposed. The proposed fuzzy similarity measure considers the relative distance between data and cluster centers in addition to the Euclidean distance to decide the degree of similarity. The boundary of a cluster center is constracted on the competitive region and expanded on the less competitive region. This result shows the possibility of using relative distance as a similarity measure.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.4
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• pp.460-465
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• 2006

This paper presents a new fuzzy learning rule which considers the Euclidean distances between the input vector and the prototypes of classes. The new fuzzy learning rule is integrated into the supervised IAFC neural network 4. This neural network is stable and plastic. We used iris data to compare the performance of the supervised IAFC neural network 4 with the performances of back propagation neural network and LVQ algorithm.

• Journal of Korea Multimedia Society
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• v.3 no.3
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• pp.241-252
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• 2000

In this paper, a translation, rotation and scale invariant system for the recognition of closed 2-D images using the bispectrum of a contour sequence and a weighted fuzzy classifier is derived and compared with the recognition process using one of the competitive neural algorithm, called a LVQ( Loaming Vector Quantization). The bispectrum based on third order cumulants is applied to the contour sequences of an image to extract fifteen feature vectors for each planar image. These bispectral feature vectors, which are invariant to shape translation, rotation and scale transformation, can be used to the represent two-dimensional planar images and are fed into a weighted fuzzy classifier. The experimental processes with eight different shapes of aircraft images are presented to illustrate a relatively high performance of the proposed recognition system.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.10a
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• pp.90-93
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• 1998

입？출력 데이터 쌍만을 이용하여 규칙 및 소속 함수를 자동적으로 결정하는 자기 학습 퍼지 알고리즘 중에서, 가장 이해하기 용이하고 퍼지 규칙 및 소속 함수 생성이 빠른 방법으로 기울기 강하를 이용한 방법들이 있다. 기울기 강하를 이용한 방법중에서 가장 대표적인 Araki가 제안한 방법은 퍼지 조건부가 퍼지 집합 형태이고 결론부는 단일값으로 구성된 알고리즘으로써 입력 퍼지 공간을 세분화하면서 시스템을 규명해나가는 간단하면서도 효율적인 알고리즘이다. 그러나 이 방법은 퍼지 입력 변수가 증가하면 퍼지 공간이 세분화 되면서 소속 함수 및 규칙 생성 개수가 급격히 제곱배로 증가하는 문제점을 가지고 있다. 따라서, 본 논문에서는 퍼지 입력 변수가 증가함에 따라 급격히 퍼지 규칙 및 소속 함수의 수가 증가하는 Araki 알고리즘의 문제점을 분석하여 소속 함수 및 규칙 수의 급격한 증가를 억제하고 Araki 방법에 비해 학습속도가 현저히 향상된 새로운 방안을 제안한다. 연구 결과, Arki 방법이 입력 변수의 개수가 증가 할수록 규칙 수가 기하 급수적으로 많이 필요하였던 것에 비해 제안한 방법은 훨씬 적은 규칙 수로 우수한 성능을 얻을 \ulcorner 있었다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.7
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• pp.1234-1243
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• 1992

A systematic procedure to design fuzzy PID controllers is developed in this paper. The concept of local fuzzy control cell is proposed by introducing both an adequate global control rule and membership functions to simplify a fuzzy logic controller. Fuzzy decision is made by using algebraic product and parallel firing arithematic mean, and a defuzzification strategy is adopted for improving the computational efficiency based on nonfuzzy micro-processor. A direct method, transforming the typical output of quasi-linear fuzzy operator to the digital compensator of PID form, is also proposed. Finally, the proposed algorithm is applied to an DC-servo motor. It is found that this algorithm is systematic and robust through computer simulations and implementation of controller using Intel 8097 micro-processor.

• The KIPS Transactions:PartB
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• v.17B no.2
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• pp.177-182
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• 2010

This paper proposes a new document clustering method using PCA and fuzzy association. The proposed method can represent an inherent structure of document clusters better since it select the cluster label and terms of representing cluster by semantic features based on PCA. Also it can improve the quality of document clustering because the clustered documents by using fuzzy association values distinguish well dissimilar documents in clusters. The experimental results demonstrate that the proposed method achieves better performance than other document clustering methods.

• Computational Structural Engineering
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• v.4 no.3
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• pp.107-115
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• 1991

A probabilistic-Fuzzy model for seismic hazard analysis is developed. The proposed model is able to reproduce both the randomness and the imprecision in conjunction with earthquake occurrences. Results-of this research are (a) membership functions of both peak ground accelerations associated with a given probability of exceedance and probabilities of exceedance associated with a given peak ground acceleration, and (b) characteristic values of membership functions at each location of interest. The proposed probabilistic-fuzzy model for assessment of seismic hazard is successfully applied to the Wasatch Front Range in Utah in order to obtain the seismic maps for different annual probabilities of exceedance, different peak ground accelerations, and different time periods.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.10a
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• pp.383-385
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• 2018

기존의 한방 자가 진단 방법에서는 PCM 기반의 알고리즘을 적용시켰으나 고질적인 문제점 중의 하나인 증상 수가 급격하게 증가할 경우에는 진단 결과가 정확하게 도출되지 않는 현상이 발생한다. 이러한 문제점을 개선하는데 효율적인 퍼지 의사 결정 트리 알고리즘을 적용한다. 퍼지 의사 결정 트리는 과거의 데이터를 미리 학습시킨 후에 엔트로피에 따라 경계 값을 구한 후, 사용자가 여러 증상을 입력하면 입력된 증상에 해당되는 상위 질병 5개를 도출한다. 그리고 도출된 상위 5개의 질병과 도출된 질병의 원인과 치료하기 위한 민간요법을 제공한다. 질병과 증상에 대한 데이터베이스는 한의사가 추천한 여러 한의학 전문 서적을 기반으로 증상과 질병의 데이터베이스를 설계한 후, 한의학 전문의의 검증을 거쳐 구현하였다. 제안된 한방 자가 진단 시스템은 과거의 데이터를 바탕으로 증상을 학습함으로써 기존의 질병 진단 시스템보다 정확하고 신속한 진단 결과를 도출하는 것을 확인하였다.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.4
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• pp.471-475
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• 2008

Microarray technology in biological science enables molecular level observations and analyses on the biological phenomina by allowing to measure the RNA expression profiles in cells. Microarray data analysis is applied in various purposes such as identifying significant genes which react to drug treatment, understanding the genome scale phenomina. In drug response experiments, the microarray-based gene expression analysis could provide meaningful information. It is sometimes needed to identify the genes which shows different expression behavior for treatment group and normal group each other. When the normal group shows the medium level expression, it is not easy to discriminate the group just by expression level comparison. This paper proposes a method which selects group-wise representative values for each gene and sets the value range of the groups in order to filter out the genes with specific pattern. It also shows some experiment results.