• Title/Summary/Keyword: fuzzy measure possibility

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Assessment of Fuzzy Measure Possibility for the Electromagnetic Field according to Voltage fluctuation of the Jechon Area (제천지역 전압변동에 따른 전자계에 대한 퍼지척도 가능성 평가)

  • Kim, Sang-Chul
    • Journal of the Korean Society of Safety
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    • v.20 no.2 s.70
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    • pp.50-55
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    • 2005
  • This Paper Presents assessment of fuzzy measure Possibility far the electromagnetic field according to voltage fluctuation of the Jechon Area. To cope with substantial electromagnetic analysis, the safety assessment were analyzed the double 154kV T/L, 345kV T/L, Jechon-Ichon Jechon-Youngju, respectively. As the results of case study, in case of 345kV T/L, the electric field value was 11.4927kV/m, magnetic field value was 0.4622G at the Point about 7m away from the line in severest case. Tn assessment of fuzzy measure Possibility for the electromagnetic field, this paper use probability of fuzzy and measure of fuzziness technique.

Assessment of Fuzzy Measure Possibility for the Electromagnetic Field of unbalanced two coupled Three-phase Transmission line Considering toad-Voltage Characteristics (부하의 전압특성을 고려한 3상 2회선 불평형 송전선로에서의 전자계에 대한 퍼지척도 가능성평가)

  • 송현선;김상철
    • Journal of the Korean Society of Safety
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    • v.16 no.3
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    • pp.45-52
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    • 2001
  • This paper presents a study on the assessment of fuzzy measure possibility for the electromagnetic field of unbalanced system. It takes into account m untransposed transmission line and unbalanced load. A three phase load flow program was developed which employs a Newton-Raphson method as a tool to analyze system unbalanced. This research presents a method of handling two coupled three phase transmission system unbalance analysis and unbalanced power demand as a function of voltages. In assessment of fuzzy measure possibility for the electromagnetic field, this paper use probability of fuzzy and measure of fuzziness technique.

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Assessment of Possibility on the Human Risk for the Electromagnetic Field of Unbalanced Two Coupled Three-phase Transmission Line Using Fuzzy Theory (퍼지이론을 이용한 3상 2회선 불평형 송전선로에서의 전자계에 대한 인체 위험 가능성평가)

  • Kim, Sang-Chul;Kim, Doo-Hyun
    • Journal of the Korean Society of Safety
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    • v.21 no.2 s.74
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    • pp.22-28
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    • 2006
  • This paper presents assessment of possibility on the human risk for the electromagnetic field of unbalanced two coupled three-phase transmission line using fuzzy theory. Three phase load flow program was developed which employed a Newton-Raphson method as a tool to analyze system unbalanced. This research presents a method of handling two coupled three phase transmission system unbalance analysis and unbalanced power demand as a function of voltages. As the results of case study, in case of 345[kV] T/L, the electric field intensity was 10.9540[kV/m], magnetic field intensity was 0.2567[G] in severest case. The results showed that the membership of a proposition fuzzy '10.9540 [kV/m] is hazardous' is 0.6349. As the analytic results using the fuzzy qualifier term, the membership in case of very false is 0.1379 and fairly false is 0.6124, respectively. In assessment of fuzzy measure possibility for the electromagnetic field, this paper used probability of fuzzy arid measure of fuzziness technique.

Power System Fault Diagnosis using Possibility Theory (가능성 이론을 이용한 전력계통 고장진단)

  • Lee, Heung-Jae;Lee, Chul-Kyun;Park, Deung-Yong;Kim, Seong-Hee;Ahn, Bok-Shin
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.6
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    • pp.665-670
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    • 1999
  • This paper introduces a fuzzy expert systems for fault diagnosis, where the causal relationships between faults and protective devices are defined as fuzzy relations. The uncertainties existing in the fault diagnosis are figured out using the possibility theory and the possibility measure is associated with the fuzzy relation to evaluate the possibilities of faults. Besides, the knowledge base in the expert system is described and explained. In this way, multiple-fault can be handled easily and simultaneously together with single faults.

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FUZZY RISK MEASURES AND ITS APPLICATION TO PORTFOLIO OPTIMIZATION

  • Ma, Xiaoxian;Zhao, Qingzhen;Liu, Fangai
    • Journal of applied mathematics & informatics
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    • v.27 no.3_4
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    • pp.843-856
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    • 2009
  • In possibility framework, we propose two risk measures named Fuzzy Value-at-Risk and Fuzzy Conditional Value-at-Risk, based on Credibility measure. Two portfolio optimization models for fuzzy portfolio selection problems are formulated. Then a chaos genetic algorithm based on fuzzy simulation is designed, and finally computational results show that the two risk measures can play a role in possibility space similar to Value-at-Risk and Conditional Value-at-Risk in probability space.

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ON THE LIMITS OF SUMS OF FUZZY NUMBERS

  • Kwon, Joong-Sung
    • Journal of applied mathematics & informatics
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    • v.5 no.1
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    • pp.153-162
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    • 1998
  • We study limits of sums of fuzzy numbers with different spreads and different shape functions where addition is defined by the sup-t-norm. We show the existence of the limit of the series of fuzzy numbers and prove the uniform continuity of the limit. Finally we investigate a law of large numbers for sequences of fuzzy numbers.

A Tuning of Intrusin Detection Model With Fuzzy Set

  • KIM Young-Soo
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.7 no.4
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    • pp.11-21
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    • 1997
  • This paper introduces a statistical approach of intrusion detection and tunes an intrusion detection model using fuzzy ste. We describel the method of applying fuzzy set for NIDES intensity measure. By using fuzzy set, we improve the algorithm for evaluating score value of NIDES, and present a possibility of intrusion detection system.

Application of fuzzy measure and fuzzy integrals model to evaluation of human interface

  • Sohn, Young-Sun;Onisawa, Takehisa
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.787-790
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    • 1997
  • This paper proposes a method which selects essential elements in a human evaluation model using the Choquet integral based on fuzzy measures, and applies the model to the evaluation of human interface. Three kinds of concepts are defined to select essential elements. Increment Degree implies the increment degree from fuzzy measures of composed elements to the fuzzy measure of a combined element. Average of Increment Degree of an element means the relative possibility of superadditivity of the fuzzy measure of each combined element. Necessity Degree means the selection degree of each combined element as a result of the human evaluation. A task experiment, which consists of a static work and two dynamic works, is performed by the use of some human interfaces. In the experiment, (1) a warning sound which gives an attention to subjects, (2) a color vision which can be distinguished easily or not, (3) the size of working area and (4) a response of confirmation that is given from an interface, are considered as human interface elements. Subjects answer the questionnaire after the experiment. From the data of the questionnaire, fuzzy measures are identified and are applied to the proposed model. Effectiveness of the proposed model is confirmed by the comparison of human interface elements extracted from the proposed model and those from the questionnaire.

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A Study on the Fuzzy Similarity Measure (퍼지 유사 척도에 관한 연구)

  • 김용수
    • 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.

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Construction of Diagnosis System for Electric-fire Causes using Fuzzy Possibility Measure (퍼지가능성 척도를 이용한 전기화재 원인진단 시스템의 구축)

  • 김두현;김상철
    • Journal of the Korean Society of Safety
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    • v.7 no.4
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    • pp.105-114
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    • 1992
  • This paper presents an study on the knowledge based system for diagnosing the fire causes using the Fuzzy Possibility Measure( FPM ) about the electric-fire ignition. The Ignition values needed for causes diagnosis is computed as FPM for electric-fire ignition based on the internal scale technique that assigns numerically the characteristic difference of facts to the-tin-ear scale. For the convinience of inference, ignition sources are classified into seven types : short, ground fault, leakge of electricity, overcurrent, cord junction overheating, bad Insulation and spark. The system for causes diagnosis of electric-fire is composed of Knowledge Acquisition System, Inference Engine and Man-Machine Interface, The diagnosis system is wrritten in an artificial intelligence langusge “PROLOG” which uses depth-first search and backward chaining schemes in reasoning process.

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