• 제목/요약/키워드: rough

검색결과 2,767건 처리시간 0.032초

3차원 거친 접촉하에서의 피로균열 시작수명에 관한 연구 (Study on the Fatigue Crack Initiation Life uncle]r 3-Dimensional Rough Contact)

  • 김태완;구영필;조용주
    • Tribology and Lubricants
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    • 제18권2호
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    • pp.160-166
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    • 2002
  • In case of rough contact fatigue, the accurate calculation of surface tractions is essential to the prediction of crack initiation life. Accurate Surface tractions influencing shear stress amplitude can be obtained by contact analysis based on the morphology of contact surfaces. In this study, to simulate rough contact under sliding condition, gaussian rough surface generated numerically in the previous study was used and to calculate clack initiation life in the substrate, dislocation pileup theory was used.

러프 집합 분류기의 성능 평가 (Performance Evaluation of Rough Set Classifier)

  • 류재홍;임창균
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1998년도 추계학술대회 학술발표 논문집
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    • pp.232-235
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    • 1998
  • This paper evaluates the performance of a rough set based pattern classifier using the benchmarks in artificial neural nets depository found in internet. The definition of rough set in soft computing paradigm is briefly introduced. next the design of rough set classifier is suggested. Finally benchmark test results are shown the performance of rough set compare to that of ANNs and decision tree.

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3차원 거친 접촉하에서의 피로균열 시작수명에 관한 연구 (Study on the Fatigue Crack Initiation Life under 3-Dimensional Rough Contact)

  • 이문주;구영필;조용주
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 2000년도 제32회 추계학술대회 정기총회
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    • pp.72-79
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    • 2000
  • In case of rough contact fatigue, the accurate calculation of surface tractions is essential to the prediction of crack initiation life. Accurate Surface tractions influencing shear stress amplitude can be obtained by contact analysis based on tile morphology of contact surfaces. In this study, to simulate rough contact under sliding condition, gaussian rough surface generated numerically in the previous study was used and to calculate crack initiation life in the substrate, dislocation pileup theory was used.

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Intuitionistic Fuzzy Rough Approximation Operators

  • Yun, Sang Min;Lee, Seok Jong
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제15권3호
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    • pp.208-215
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    • 2015
  • Since upper and lower approximations could be induced from the rough set structures, rough sets are considered as approximations. The concept of fuzzy rough sets was proposed by replacing crisp binary relations with fuzzy relations by Dubois and Prade. In this paper, we introduce and investigate some properties of intuitionistic fuzzy rough approximation operators and intuitionistic fuzzy relations by means of topology.

CERTAIN ASPECTS OF ROUGH IDEAL STATISTICAL CONVERGENCE ON NEUTROSOPHIC NORMED SPACES

  • Reena Antal;Meenakshi Chawla;Vijay Kumar
    • Korean Journal of Mathematics
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    • 제32권1호
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    • pp.121-135
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    • 2024
  • In this paper, we have presented rough ideal statistical convergence of sequence on neutrosophic normed spaces as a significant convergence criterion. As neutrosophication can handle partially dependent components, partially independent components and even independent components involved in real-world problems. By examining some properties related to rough ideal convergence in these spaces we have established some equivalent conditions on the set of ideal statistical limit points for rough ideal statistically convergent sequences.

퍼지-라프 집합을 이용한 관계 데이터베이스 구성 (Design and Implementation of Relational Database model Using Fuzzy-rough Sets)

  • 강전근;정환묵
    • 한국정보처리학회논문지
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    • 제4권1호
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    • pp.1-10
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    • 1997
  • 본 논문에서는 의미적으로 접근되어 애매성이 있으며 구별하기 힘든 자료를 효과 적으로 관리하기 위한 방안의 하나로 퍼지 집합과 라프 집합을 통합한 퍼지-라프 집 합(Fuzzy-Rough Sets:FRS)을 이용, 관계 데이터베이스를 구성하고 구현하였다. 먼저 불완전한 정보를 데이터베이스로 구성, 표현하는 방법에 대하여 일반적 관계 데이터 베이스를 확장시킨 퍼지 데이터베이스와 라프 데이터베이스를 간략히 살펴본다. 그리 고 퍼지 집합과 라프 집합을 통합한 퍼지-라프 집합을 근거로 퍼지-라프(Fuzzy -Rough:FR)관계데이터베이스를 구성한 후, 펜티엄 컴퓨터(166Mhz)상에서 데이터베이 스 관리 시스템인 엑세스(access)와 비쥬얼베이직(visual)을 도구(tool)로 구현하고 분석 하였다. 본 논문에서는 퍼지 집합의 특성과 라프 집합의 특성을 가진 집합을 기 반으로 한 데이터베이스를 구성, 구현함으로서 데이터의 감소를 유도하였다.

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벼 및 현미의 평형함수율/평형상대습도 (EMC/ERH of Rough Rice and Brown Rice)

  • 최병민
    • Journal of Biosystems Engineering
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    • 제30권2호
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    • pp.95-101
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    • 2005
  • Adsorption and desorption experiments were carried out on rough rice and brown rice (Nampyung) at 5, 15, 25, 35, $45^{\circ}C$ for moisture contents between 8.7 and $25\%$ (db). The method employed was to measure the equilibrium relative humidity (ERH) of air in contact with the grain under static conditions, using an electronic hygrometer The effects of temperature and moisture contents were investigated, and the measured values were fitted to the modified Henderson, the modified Chung-Pfost, the modified Halsey and the modified Oswin model. The ERHs of rough rice and brown rice decreased with an decrease in moisture content and temperature, and the effects of temperature was no significant at moisture content of $25\%$ (db). Equilibrium moisture content (EMC) of brown rice was higher than rough rice at same temperature and relative humidity. Desorption EMC is higher than the adsorption, but there is no significant difference between desorption and adsorption EMC in moisture content near $25\%$ (db) at rough rice and near 9, 21 and $25\%$ (db) at brown rice. The modified Oswin model was the best in describing the adsorption EMC and the modified Chung-Pfost model was the best in describing the adsorption ERH of rough rice. The modified Oswin model was the best in describing the adsorption EMC/ERH of brown rice. The modified Chung-Pfost model was the best in describing the desorption EMC/ERH of rough rice and brown rice.