• Title/Summary/Keyword: Fuzzy assessment

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PERFORMANCE INDEX-An Assessment Indicator of Concrete Bridges (콘크리트 교량의 상태 평가를 위한 성능지수)

  • Kim, Kyoung-Soo;Cabrera, J.G.
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.1 no.2
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    • pp.131-140
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    • 1997
  • 콘크리트 교량을 저렴하고 신속하게 상태 평가를 하기 위하여 성능 지수(Performance Index)를 제안한다. 이 기법은 육안 검사에 의하여 발견된 결함의 범위와 심각도를 사용하여 콘크리트 교량의 전반적인 상태를 신속하게 등급화 하고 콘크리트 교량의 노출 조건을 고려하여 콘크리트 성능을 정량적으로 평가한다. 또한 본 연구에서는 상기한 성능 지수 기법의 타당성을 증명할 수 있는 정밀 안전 진단 시험결과를 활용하여 6개의 주요 노후화 원인을 고려하는 또 다른 성능 지수를 제안한다. 이러한 두 상태 평가 방법이 영국의 실제 교량 상태 평가 자료를 바탕으로 한 상태 평가 결과를 퍼지 집합 이론(fuzzy set theory)으로 분석한 결과와 비교하여 방법의 정당성 및 신뢰성을 논의한다.

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Comprehensive evaluation method for user interface design in nuclear power plant based on mental workload

  • Chen, Yu;Yan, Shengyuan;Tran, Cong Chi
    • Nuclear Engineering and Technology
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    • v.51 no.2
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    • pp.453-462
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    • 2019
  • Mental workload (MWL) is a major consideration for the user interface design in nuclear power plants (NPPs). However, each MWL evaluation method has its advantages and limitations, thus the evaluation and control methods based on multi-index methods are needed. In this study, fuzzy comprehensive evaluation (FCE) theory was adopted for assessment of interface designs in NPP based on operators' MWL. An evaluation index system and membership functions were established, and the weights were given using the combination of the variation coefficient and the entropy method. The results showed that multi-index methods such as performance measures (speed of task and error rate), subjective rating (NASA-TLX) and physiological measure (eye response) can be successfully integrated in FCE for user interface design assessment. The FCE method has a correlation coefficient compared with most of the original evaluation indices. Thus, this method might be applied for developing the tool to quickly and accurately assess the different display interfaces when considering the aspect of the operators' MWL.

Self-Directed Learning Assessment System Using Fuzzy Logic (퍼지 논리를 이용한 자기 주도적 학습 및 평가 시스템)

  • Woo, Young-Woon;Kim, Kwang-Baek;Lee, Jong-Hee
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.4
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    • pp.815-825
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    • 2007
  • The existing web-based self-directed learning systems are in short for the ability of learning skills assessment. Even worse, hey only give test scores as an indicate for test skills, which is also not a good measure for learning skills assessment and makes it difficult to assess learning skills objectively and to present clear assessment criterion. In this paper, we proposed an improved self-directed learning system using fuzzy logic, which can be controlled by learners themselves and helps to evaluate their on learning process. We also implemented the system on the written examination of Engineer Information Processing. The purposed system lust calculates membership functions of learning tine, learning frequency, testing time, and test score. Using them the final membership functions of learning and test skills are calculated and presented in a graphical, i.e. mon understandable, way to user. The purposed system helps learners to assess their achievement and to plan future schedule, and the survey result on the students used the system also supports that.

The plant fault diagnostic system of the using fuzzy FTA (퍼지 FTA를 이용한 설비고장진단 시스템)

  • 박주식;김길동;박상민
    • Proceedings of the Safety Management and Science Conference
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    • 2000.05a
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    • pp.207-215
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    • 2000
  • This study deals with the application of knowledge-engineering and a methodology for the assessment & measurement of reliability, availability, maintainability, and safety of industrial systems using fault-tree representation. A fuzzy methodology for fault-tree evaluation seems to be an alternative solution to overcome the drawbacks of the conventional approach(insufficient information concerning the relative frequences of hazard events). To improve the quality of results, the membership functions must be approximated based on heuristic considerations. The purpose of this Is to describe the knowlwdge engineering approach, directed to integrate the various sources of knowledge involved in a FTA.

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The plant fault diagnostic system using fuzzy FTA (퍼지 FTA를 이용한 설비고장진단 시스템)

  • 박주식;김길동;강경식
    • Journal of the Korea Safety Management & Science
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    • v.2 no.2
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    • pp.1-10
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    • 2000
  • This study deals with the application of knowledge engineering and a methodology for the assessment and measurement of reliability, availability, maintainability, and safety of industrial systems using fault-tree representation. A fuzzy methodology for fault-tree evaluation seems to be an alternative solution to overcome the drawbacks of the conventional approach (insufficient information concerning the relative frequence of hazard events). To improve the quality of results, the membership functions must be approximated based on heuristic considerations. The purpose of this study is to describe the knowledge engineering approach, directed to integrate the various sources of knowledge involved in a FTA.

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Image Analysis Fuzzy System

  • Abdelwahed Motwakel;Adnan Shaout;Anwer Mustafa Hilal;Manar Ahmed Hamza
    • International Journal of Computer Science & Network Security
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    • v.24 no.1
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    • pp.163-177
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    • 2024
  • The fingerprint image quality relies on the clearness of separated ridges by valleys and the uniformity of the separation. The condition of skin still dominate the overall quality of the fingerprint. However, the identification performance of such system is very sensitive to the quality of the captured fingerprint image. Fingerprint image quality analysis and enhancement are useful in improving the performance of fingerprint identification systems. A fuzzy technique is introduced in this paper for both fingerprint image quality analysis and enhancement. First, the quality analysis is performed by extracting four features from a fingerprint image which are the local clarity score (LCS), global clarity score (GCS), ridge_valley thickness ratio (RVTR), and the Global Contrast Factor (GCF). A fuzzy logic technique that uses Mamdani fuzzy rule model is designed. The fuzzy inference system is able to analyse and determinate the fingerprint image type (oily, dry or neutral) based on the extracted feature values and the fuzzy inference rules. The percentages of the test fuzzy inference system for each type is as follow: For dry fingerprint the percentage is 81.33, for oily the percentage is 54.75, and for neutral the percentage is 68.48. Secondly, a fuzzy morphology is applied to enhance the dry and oily fingerprint images. The fuzzy morphology method improves the quality of a fingerprint image, thus improving the performance of the fingerprint identification system significantly. All experimental work which was done for both quality analysis and image enhancement was done using the DB_ITS_2009 database which is a private database collected by the department of electrical engineering, institute of technology Sepuluh Nopember Surabaya, Indonesia. The performance evaluation was done using the Feature Similarity index (FSIM). Where the FSIM is an image quality assessment (IQA) metric, which uses computational models to measure the image quality consistently with subjective evaluations. The new proposed system outperformed the classical system by 900% for the dry fingerprint images and 14% for the oily fingerprint images.

Aggregation Based on Situation Assessment (상황 평가에 기반을 둔 병합)

  • Choi, Dae-Young
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.10
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    • pp.2584-2590
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    • 1998
  • In the existing fuzzy aggregation method, the operators such as t-norm, t conorm, mean operator, Yafer's operator and $\gamma$ operator are used to aggregate the values of membership functions. However, these methods have problems in that they do not reflect the decision situation properlyin the decision process. In order to solve these problems we suggest a situation assessment model(SAM) to reflect the decision situation in the decision proess. In the fuzzy decision environment, we propose a new aggregation method to reflect the decision situation using the result of SAM. We call it the aggregation based on situation assessment (ASA) method. It makes the stepwise aggregation with derection according to the decision situation. Moreover, we compare ASA method with the existing aggregation methods.

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Evaluating future deforestation to assess REDD implementation suitability study on Kon Tum province in Vietnam (베트남 Kon Tum 지역에서의 산림훼손지역 예측을 통한 REDD 적지 분석)

  • Tanaka, Riwako;Lee, Dongkun;Jung, Taeyong;Ryu, Jieun
    • Journal of Environmental Impact Assessment
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    • v.22 no.6
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    • pp.649-657
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    • 2013
  • UNFCCC(United Nations Framework Convention on Climate Change) agreed with Reducing emissions from deforestation and forest degradation(REDD). It is necessary to develop the method of REDD suitability assessment in national scale. Existing researches suggested projection methods of deforestation area by many deforestation factors, but the causes of deforestation were different by regions. Therefore, in this study, REDD suitability in Kon Tum province in Vietnam was analyzed by several significant deforestation factors. REDD suitability value was computed using the Fuzzy set. As a result, all deforestation factors related to deforestation area and the REDD suitability value was the highest in Sa Thay district, Dak Glei district, Kon Plong district and Dak Ha district. These provinces have high biodiversity, on the other hand deforestation problem has been occurred.

A fuzzy expert system for diagnosis assessment of reinforced concrete bridge decks

  • Ramezanianpour, Ali Akbar;Shahhosseini, Vahid;Moodi, Faramarz
    • Computers and Concrete
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    • v.6 no.4
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    • pp.281-303
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    • 2009
  • The lack of safety of bridge deck structures causes frequent repair and strengthening of such structures. The repair induces great loss of economy, not only due to direct cost by repair, but also due to stopping the public use of such structures during repair. The major reason for this frequent repair is mainly due to the lack of realistic and accurate assessment system for the bridge decks. The purpose of the present research was to develop a realistic expert system, called Bridge Slab-Expert which can evaluate reasonably the condition as well as the service life of concrete bridge decks, based on the deterioration models that are derived from both the structural and environmental effects. The diagnosis assessment of deck slabs due to structural and environmental effects are developed based on the cracking in concrete, surface distress and structural distress. Fuzzy logic is utilized to handle uncertainties and imprecision involved. Finally, Bridge Slab-Expert is developed for prediction of safety and remaining service life based on the chloride ions penetration and fick's second law. Proposed expert system is based on user-friendly GUI environment. The developed expert system will allow the correct diagnosis of concrete decks, realistic prediction of service life, the determination of confidence level, the description of condition and the proposed action for repair.

The Fuzzy QFD Approach to Importance the Public Sector Information Performance Measurement Category (퍼지 QFD를 활용한 공공부문 정보화 성과 측정범주 중요도 도출)

  • Oh, Jin-Seok;Song, Young-Il
    • Information Systems Review
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    • v.12 no.2
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    • pp.189-203
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    • 2010
  • Is presenting guidance of information performance measurement as government PRM version 2.0 these common reference models in public sector. Government PRM is consisted of assessment classification system and standard line of sight and performance management standard form. Through this, is sorting performance element and define cause-and effect. Government PRM is supplying measurement categories at assessment classification system, but relative importance for application standard by measurement categories is not presenting. In this study, importance for government PRM's measurement categories been applying by commonness Test of information performance measurement of public sector wishes to deduce estimation and priority. Research model used Fuzzy QFD, and designed so that can reflect well PRM's development purpose. I applied Fuzzy AHP and FPP method that graft together fuzzy theory to minimize uncertainty and ambiguity in that expert opinion. Is drawn to element that "Standard model offer for information department and management" is the most important in government PRM's development purpose. "Quality of service" is showing the highest priority in customer results in measurement category. Importance for government PRM's measurement categories can offer common valuation basis in government and public institution. Hereafter if examine closely quantitative cause-and effect for structure model of measurement classification system when study government PRM more objective and efficient reference model become.