• 제목/요약/키워드: Numeric analysis

검색결과 224건 처리시간 0.025초

Representation of Spatial Relations between Regions in a 2D Segmented Image

  • Ralescu, Anca;Miyajima, Koji
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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    • pp.1317-1320
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    • 1993
  • We are concerned with developing a robust method for comprehensive scene analysis. In particular, we address the problem of representing spatial relations between regions in a segmented 2D image. Spatial relations are modeled as fuzzy sets. The method has two aspects, symbolic and quantitative, consisting of assigning labels for spatial relations and numeric degrees to which a relation holds respectively. The procedure of deriving a spatial relation is hierarchical taking into account geometric/physical characteristics of the regions in question.

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Uncertainty Analysis of Concrete Structures Using Modified Latin Hypercube Sampling Method

  • Yang, In-Hwan
    • International Journal of Concrete Structures and Materials
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    • 제18권2E호
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    • pp.89-95
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    • 2006
  • This paper proposes a modified method of Latin Hypercube sampling to reduce the variance of statistical parameters in uncertainty analysis of concrete structures. The proposed method is a modification of Latin Hypercube sampling method. This analysis method uses specifically modified tables of random permutations of ranked numbers. In addition, the Spearman coefficient is used to make modified tables. Numerical analysis is carried out to predict the uncertainty of axial shortening in prestressed concrete bridge. Statistical parameters obtained from modified Latin Hypercube sampling method and conventional Latin Hypercube sampling method are compared and evaluated by a numeric analysis. The results show that the proposed method results in a decrease in the variance of statistical parameters. This indicates the method is efficient and effective in the uncertainty analysis of complex structural system such as prestressed concrete bridges.

Modal analysis of cracked cantilever composite beams

  • Kisa, Murat;Arif Gurel, M.
    • Structural Engineering and Mechanics
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    • 제20권2호
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    • pp.143-160
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    • 2005
  • Modal analysis of cracked cantilever composite beams, made of graphite-fibre reinforced polyamide, is studied. By using the finite element and component mode synthesis methods, a numeric model applicable to investigate the vibration of cracked composite beams is developed. In this new approach, from the crack section, the composite beam separated into two parts coupled by a flexibility matrix taking into account the interaction forces. These forces are derived from the fracture mechanics theory as the inverse of the compliance matrix calculated with the proper stress intensity factors and strain energy release rate expressions. Numerical results are obtained for modal analysis of composite beams with a transverse non-propagating open crack, addressing the effects of the location and depth of the crack, and the volume fraction and orientation of the fibre on the natural frequencies and mode shapes. By means of modal data, the position and dimension of the defect can be found. The results of the study confirmed that presented method is suitable for the vibration analysis of cracked cantilever composite beams. Present technique can be easily extended to composite plates and shells.

Simulator Output Knowledge Analysis Using Neural network Approach : A Broadand Network Desing Example

  • Kim, Gil-Jo;Park, Sung-Joo
    • 한국시뮬레이션학회:학술대회논문집
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    • 한국시뮬레이션학회 1994년도 추계학술발표회 및 정기총회
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    • pp.12-12
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    • 1994
  • Simulation output knowledge analysis is one of problem-solving and/or knowledge adquistion process by investgating the system behavior under study through simulation . This paper describes an approach to simulation outputknowldege analysis using fuzzy neural network model. A fuzzy neral network model is designed with fuzzy setsand membership functions for variables of simulation model. The relationship between input parameters and output performances of simulation model is captured as system behavior knowlege in a fuzzy neural networkmodel by training examples form simulation exepreiments. Backpropagation learning algorithms is used to encode the knowledge. The knowledge is utilized to solve problem through simulation such as system performance prodiction and goal-directed analysis. For explicit knowledge acquisition, production rules are extracted from the implicit neural network knowledge. These rules may assit in explaining the simulation results and providing knowledge base for an expert system. This approach thus enablesboth symbolic and numeric reasoning to solve problem througth simulation . We applied this approach to the design problem of broadband communication network.

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고해상도 영상레이더 성능 분석을 위한 모델링 및 시뮬레이션 기법 (Modeling and Simulation Techniques for Performance Analysis of High Resolution SAR System)

  • 성진봉;김세영;이현익;전병태
    • 한국전자파학회논문지
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    • 제24권5호
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    • pp.558-565
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    • 2013
  • 본 논문에서는 고해상도 광대역 영상레이더의 성능을 분석하기 위하여 시간, 주파수 및 Numeric 영역에서 아날로그, RF 및 디지털 신호처리 해석을 통합할 수 있는 시스템 시뮬레이션 툴인 Agilent사의 ADS Ptolemy DF(TSDF: Timed Synchronous DataFlow)를 이용하여 모델링 및 시뮬레이션을 수행하였다. 영상레이더용 하드웨어 시스템은 안테나, 통제장치 및 송수신 장치로 크게 구성되며, 송수신 장치는 고주파 변환 장치, 고출력 송신 장치, 그리고 송수신 전단 장치로 구성된다. 본 논문에서는 시스템의 하드웨어 성능에 영향을 미치는 오차 변수를 정의하고, 이들 오차 변수의 오차 원인이 되는 부품에 대한 특성을 모델링하였다. 영상레이더는 TSDF 모델링 기법을 이용하여 순방향 전송 임펄스 특성($S_{21}$), 고주파 소자의 비선형 특성(이득 비선형, 3차 intercept 및 믹서 교차변조), 채널간 전파 특성, 주파수 합성기 위상 잡음, TWTA의 진폭/위상 특성, 파형 발생기의 샘플링 주파수 및 I/Q 밸런스 등에 대한 모델링을 수행하여 SAR 성능을 분석하였으며, 최종 임펄스 응답 특성 분석을 통한 시스템의 하드웨어 규격을 도출하였다.

한국 미혼 여성의 하반신체형 분석과 체형변인이 플레어스커트 입체성능에 미치는 영향(II) (Analysis of Lower body on Korean Young Women and the Effect of the Lower body Type on the Shape of Flare Skirt (II))

  • 조정미
    • 대한가정학회지
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    • 제30권3호
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    • pp.15-32
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    • 1992
  • The purpose of this study was to detect the effect of the lower body type on the shape of flare skirts. The subjects for the wearing test were 50 female students, who were controlled in their hip and waist shapes. The skirts used for wearing test were six types(three flar angles $\times$ two fabric types). The effect of lower body type on the shape of flare skirts was determind by the hemline trace method and the silhouette photography. The data were then analyzed by the repeated measures of analysis of variance and the SNK multiple range test. The results obtained from this study were as follows : 1) When a flare skirt made with larger flare angle and better drapable fabric was worn, the numeric of the nodes increased as the drop value(hip - waist) increased. When a flare skirt made with smaller flare angle was worn, the width of horizontal sectio of hemline increased as the drop value increased. The hemline uneveness decreased on the sides and back as the drop value increased. When a flare skirt made with worse drapable fabric was worn, the sides angle of the flarskirt increased as the drop value increased. 2) When a flare skirt made with larger flare angle was worn, the numeric of nodes increased as the ratio of dropped hip increased. The wave-height increased and the back variation ratio of wave-height was higher than the front variation ratio of wave-height as the ratio of dropped hip increased. The hemiline uneveness decreased on the back as the ratio of dropped hip increased. When a flare skirt made with larger flare angle was worn, the sides angle of the flare skirt increased as the ratio of dropped hip increased.

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전자상거래 서비스 품질 인증에 관한 연구 (Certifying the Quality of Electronic Commerce Services)

  • 최덕원
    • 품질경영학회지
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    • 제33권2호
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    • pp.1-12
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    • 2005
  • An extensive literature review has been made in this paper to build the evaluation hierarchy structure for the certification of electronic commerce services. In building the evaluation hierarchy structure, major candidate evaluation factors are selected by bench marking the various certification practices, including the Malcolm Baldrige award, ISO9000, and BSC(balanced scorecard) techniques. This paper deployed principal component analysis and factor analysis techniques to develop a statistically solid and systematic evaluation model. The final evaluation model, as presented in this paper as a model for the certification of electronic commerce services, produces a numeric score on the 100% scale, which can be served as a metric for the certification decision. The AHP technique was used in converting the various qualitative and quantitative evaluation values into a single measure for the certification decision.

빅데이터 분석결과에 대한 해석 : 브랜드 인지도와 선호도를 중심으로 (The Interpretation of Results from Big Data Analysis : Focusing on Brand Awareness and Preference)

  • 김도관
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2016년도 추계학술대회
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    • pp.117-119
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    • 2016
  • 빅데이터 분석 결과를 제공하는 사이트들은 분석 결과에 있어 단순한 수치결과만을 제시해주고 있으며, 그 결과에 대한 사회현상 및 트랜드에 대한 해석을 제공하지는 않고 있다. 이러한 점에서 본 연구에서는 빅데이터 분석 결과의 검토를 통해서 브랜드와 선호도를 파악하는 방법을 통하여 빅데이터 분석결과에 대한 해석 방법을 제시하고 한다.

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Effect of model calibration on seismic behaviour of a historical mosque

  • Demir, Ali;Nohutcu, Halil;Ercan, Emre;Hokelekli, Emin;Altintas, Gokhan
    • Structural Engineering and Mechanics
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    • 제60권5호
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    • pp.749-760
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    • 2016
  • The objective of the study is to investigate the effects of model calibration on seismic behaviour of a historical mosque which is one of the most significant Ottomon structures. Seismic analyses of calibrated and noncalibrated numeric models were carried out by using acceleration records of Kocaeli earthquake in 1999. In numerical analysis, existing crack zones on real structure was investigated in detail. As a result of analyses, maximum stresses and displacements of calibrated and noncalibrated numerical models were compared each other. Consequently, seismic behaviour and damage state of historical masonry Hafsa Sultan mosque was determined as more realistic in the event of a severe earthquake.

Torque Converter의 설계 및 유동해석 (Design and Flow Analysis of Torque Converter)

  • 박재인;조강래
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 1998년도 강연회 및 연구개발 발표회 논문집
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    • pp.3-10
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    • 1998
  • The situation frequently occurs in which the input torque capacity of the converter should be changed. It is known that the modification of the ou angles of the torque converter elements is suitable for such situation with diameter of flow path of the converter maintained. But so far it has been, predict correctly the converter characteristics as well as the effects of oulet torque capacity in the past numerical methods. In the present numeric introducing the interrow mixing planes, the torque capacity was satifactorily and it was shown that the torque capacity could be effectively changed by the oulet blade angles of pump and stator.

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