• Proceedings of the KIEE Conference
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• 1991.11a
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• pp.31-34
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• 1991

This paper presents a voltage-reactive power control algorithm considering fuzziness. In this paper, a coordination technique based on fuzzy set theory is applied for system loss-voltage compromises. Here, we introduce membership functions to measure the adaptability of real power loss of transmission line and the deviation of load bus voltage from the constraints. Then the optimization of problem is solved by a linear programming technique considering the fuzzy set theory. The objective is a degree of satisfaction about the fuzzy decision-making function. The effectiveness of this algorithm has been verified by testing on sample systems.

• Journal of Internet Computing and Services
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• v.4 no.2
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• pp.61-67
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• 2003

It has recently become known that the social issue of obesity, caused by increased caloric intake and lack of exercise, is a risk factor in the cause of various adult diseases. Above all, to prevent or cure obesity, we must accurately evaluate the degree of obesity, and we have used BML, WHR, and waist measurements for this purpose. In this paper, we propose an obesity evaluation system based on fuzzy inference using BML and waist measurement. For this purpose, we decided reasoning rule and membership function about BML and waist measurements. The inference result is presented in a descriptive sentence.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.364-367
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• 2003

In this study, we develop a method for recognizing face images by combining wavelet decomposition, fisherface method, and fuzzy integral. The proposed approach comprises of four main stages. The first stage uses the wavelet decomposition. As a result of this decomposition, we obtain four subimages. The second stage of the approach applies a fisherface method to these four subimage sets. The two last phases are concerned with the generation of the degree of fuzzy membership and the aggregation of the individual classifiers by means of the fuzzy integral. The experimental results obtained for the CNU and Yale face databases reveal that the approach presented in this study yields better classification performance in comparison to the results produced by other classifiers.

• Journal of the Korean Data and Information Science Society
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• v.20 no.6
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• pp.1177-1190
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• 2009

In this paper, we propose a fuzzy proxy cache scheme for caching web documents in mobile base stations. In this scheme, a mobile cache model is used to facilitate data caching and data replication. Using the proposed cache scheme, the individual proxy in the base station makes cache decisions based solely on its local knowledge of the global cache state so that the entire wireless proxy cache system can be effectively managed without centralized control. To improve the performance of proxy caching, the proposed cache scheme predicts the direction of movement of mobile hosts, and uses various cache methods for neighboring proxy servers according to the fuzzy-logic-based control rules based on the membership degree of the mobile host. The performance of our cache scheme is evaluated analytically in terms of average response delay and average energy cost, and is compared with that of other mobile cache schemes.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2001.12a
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• pp.95-98
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• 2001

In this paper, we propose a method how to determine the medical section select that get input the conditions of illness from a dialog-box using a fuzzy logic as a guidance system of the Cyber Hospital. It is to offer an output the most matched section for medical treatment using the Algebraic product fuzzy inference and Max inference after match the membership degree table of symptoms of received input from patient and their information. It will present of the direction for ignored patient which of a medical section select.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.125-127
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• 2000

Multiple faults are hard to diagnose correctly because the operation of circuit breakers tripped by former fault changes the topology of power systems. The information including operating time of actuated relays and tripped circuit breakers is used for considering changes of the network topology in fault section diagnosis. This paper presents a method for fault section diagnosis using a set of matrices which represent changes of the network topology due to operation of circuit breakers. The proposed method uses fuzzy relation to cope with the unavoidable uncertainties imposed on fault section diagnosis of power systems. The inference executed by the proposed matrices provides the fault section candidates in the form of a matrix made up of the degree of membership. Experimental studies for real power systems reveal usefulness of the proposed technique to diagnose multiple faults.

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.63-67
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• 1999

This paper presents the optimization of CFRP laminated rectangular plates using fuzzy theory. In optimization, thickness of CFRP lamina and fiber angle are taken as design variables, and total thickness of the plates is minimized under Tsai-Hill failure criterion. The uncertainties are entered by introducing fuzzy material strengths and then the objective and constraints are represented by a membership function of their own according to the intersection method. Various design results are presented for the CFRP laminated composites plates.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.1
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• pp.35-42
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• 1998

This paper presents the introduction of Pseudo-2 axes robot module and its GA-based fuzzy control implementation. Pseudo-2 axes robot module which use a single motor and controller for driving 2 joints of a robot mechanism, is devised towards a lower priced robot with its degree of freedom maintained GA-based Fuzzy controller is considered for the better control implementation of the developed system than the conventional PID controller. Here. the scaling factors of the membership function with high fitness values are selected using a genetic algorithm for a pulse-type input trajectory. The obtained controller also shows better trajectory tracking performance than a PID controller.

• Journal of the Korean Society of Safety
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• v.12 no.1
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• pp.122-128
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• 1997

A new approach, called "two-phase approach", has been proposed In this study. Using this approach to solve MONLP(multiobjective nonlinear programming problem), the solution process is divied into two phase. In the first phase, the min-operator is used to aggregate the membership degree of fuzzy goals and constraints. In the second phase, the $\gamma$-operator is used to test and find an efficient solution in the sense of nondominated. It has been shown that no matter what the solution of the problem is unique or not, an efficient solution can be always obtained at the second phase. The proposed approach can be applied to industrial safety problem with multiobjective problems. On the basis of proposed approach, an illustrative numerical example is presented.presented.

• Journal of applied mathematics & informatics
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• v.35 no.1_2
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• pp.95-111
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• 2017

Recently, interval-valued fuzzy graph is a growing research topic as it is the generalization of fuzzy graphs. The interval-valued fuzzy graphs are more flexible and compatible than fuzzy graphs due to the fact that they allowed the degree of membership of a vertex to an edge to be represented by interval values in [0.1] rather than the crisp values between 0 and 1. In this paper, we introduce the concepts of regular and totally regular interval-valued fuzzy graphs and discusses some properties of the ${\mu}$-complement of interval-valued fuzzy graph. Self ${\mu}$-complementary interval-valued fuzzy graphs and self-weak ${\mu}$-complementary interval-valued fuzzy graphs are defined and a necessary condition for an interval valued fuzzy graph to be self ${\mu}$-complementary is discussed. We define busy vertices and free vertices in interval valued fuzzy graph and study their image under an isomorphism.