• 제목/요약/키워드: model integration

검색결과 2,832건 처리시간 0.027초

지반재료의 비등방경화 구성모델에 대한 응력적분 알고리즘 (Stress Integration Algorithm for an Anisotropic Hardening Constitutive Model of Geomaterials)

  • 오세붕;이진구;김태경
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2005년도 춘계 학술발표회 논문집
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    • pp.343-350
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    • 2005
  • A constitutive model was implemented in ABAQUS code. The constitutive equation can model the behavior for overall range of strain level from small to large deformation, which is based on anisotropic hardening rule and total stress concept. The formulation includes (1) finite strain formulation on the basis of Jaumann rate, (2) implicit stress integration and (3) consistent tangent moduli. Therefore the mathematical background was established in order that large deformation analysis can be performed accurately and efficiently with the anisotropic constitutive model. In the large deformation analyses, geometric nonlinearity was considered and the result of analyses with the proposed model was compared with that of Mises model for the overall strain range behavior.

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수치모의를 통한 미세규모 순환과 확산에 대한 예측 (Predictions of Local Circulation and Dispersion with Microscale Numerical Model)

  • 안광득;이용희;장동언;조천호
    • 한국군사과학기술학회지
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    • 제6권4호
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    • pp.147-158
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    • 2003
  • The prediction of wind field is very important fact in the radioactive and chemical warfare. In spite of advanced numerical weather prediction modelling and computing technology, the high resolution prediction of wind field is limited by the very high integration costs. In this study we coupled the mesoscale numerical model and microscale diagnostic numerical model with minimized integration costs. This coupled model has not only the ability of prediction of high resolution wind field including complex building but also microscale pollutant diffusion fields. For military operation this system can help making a practical and cost-effective decision in a battle field.

저주파 노이즈와 BTI의 머신 러닝 모델 (Machine Learning Model for Low Frequency Noise and Bias Temperature Instability)

  • 김용우;이종환
    • 반도체디스플레이기술학회지
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    • 제19권4호
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    • pp.88-93
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    • 2020
  • Based on the capture-emission energy (CEE) maps of CMOS devices, a physics-informed machine learning model for the bias temperature instability (BTI)-induced threshold voltage shifts and low frequency noise is presented. In order to incorporate physics theories into the machine learning model, the integration of artificial neural network (IANN) is employed for the computation of the threshold voltage shifts and low frequency noise. The model combines the computational efficiency of IANN with the optimal estimation of Gaussian mixture model (GMM) with soft clustering. It enables full lifetime prediction of BTI under various stress and recovery conditions and provides accurate prediction of the dynamic behavior of the original measured data.

국제표준에 따른 기업의 대응전략 (Strategy of Korean Company for International Standardization)

  • 최성운;백봉기
    • 대한안전경영과학회지
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    • 제6권1호
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    • pp.247-256
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    • 2004
  • Recently, International Standardization is an important issue in competitive world market because of integration of standard, liberalization of international trade and globalization. Consequently, Korean companies need a strategy about corresponding to market circumstance and global standard. In this study, we examine Intellectual Property, Patent and Antitrust Law which are related to standardization. This study suggests company strategy and system integration model to dispose the global standard.

설계통합 전문분야로서의 형상설계 (Configuration Design As a Discipline of Design Integration)

  • 김구
    • 한국군사과학기술학회지
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    • 제6권4호
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    • pp.38-44
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    • 2003
  • In this paper configuration design is viewed as an engineering discipline that plays a key role in the design integration process at early-stage development of a complex and large-scale product. Taking as an instance an aircraft development program that Korean engineers had experienced in Lockheed-Martin company, the process of early-stage configuration design is recapitulated and then a role model of effective design integration activities is presented.

Continuous Improvement Through Integration of Quality Tools

  • He, Zhen;Qi, Ershi;Liu, Zixian
    • International Journal of Quality Innovation
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    • 제3권2호
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    • pp.38-45
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    • 2002
  • Continuous quality improvement is now the focus of research and application in quality engineering. To achieve continuous improvement, it's necessary to integrate quality tools and to plan, design and control the whole process of creating quality. Based on the extensive literature review and the philosophy of concurrent quality engineering, the paper analyzes the relationships among major quality tools such as QFD, FMEA, DOE and SPC and presents a basic model and structure for the integration of quality tools.

일반 등방경화 구성관계에 대한 내재적인 음력적분 : II. 검증 (Implicit Stress Integration of the Generalized Isotropic Hardening Constitutive Model : II . Verification)

  • 오세붕;이승래
    • 한국지반공학회지:지반
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    • 제12권6호
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    • pp.87-100
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    • 1996
  • 본 연구에서는 동반논문(오세붕 & 이승래, 1996)에서 정식화한 비등방경화 구성모델에 대한 내재적인 응력적분 알고리즘의 정확성과 효율성을 검증하였다. 비배수 삼축압축시험경로에 대한 오차평가를 통하여 정확도해석을 수행하였고 수치적인 굴착해석예제를 수행함으로써 정확도 및 수렴도를 분석하였다. 그 결과 제안된 알고리즘이 비등방경화 구성관계에 대하여 음력을 정화하게 적분하고 Newton 법을 이용한 비선형 해석시에 점근적인 2차 수렴도를 확보함을 알 수 있었다. 그리고 이러한 검증을 토대로 지반의 초기조건 및 시공단계를 고려한 유한요소법을 이용하여 실제 굴착문제를 해석하였다. 비등방경화 구성관계를 이용함으로써, 추정된 벽체의 변위는 Cainflay모델에 비하여 실제와 더 유사한 해석결과를 얻을 수 있었다.

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Effective Determination of Optimal Regularization Parameter in Rational Polynomial Coefficients Derivation

  • Youn, Junhee;Hong, Changhee;Kim, TaeHoon;Kim, Gihong
    • 한국측량학회지
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    • 제31권6_2호
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    • pp.577-583
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    • 2013
  • Recently, massive archives of ground information imagery from new sensors have become available. To establish a functional relationship between the image and the ground space, sensor models are required. The rational functional model (RFM), which is used as an alternative to the rigorous sensor model, is an attractive option owing to its generality and simplicity. To determine the rational polynomial coefficients (RPC) in RFM, however, we encounter the problem of obtaining a stable solution. The design matrix for solutions is usually ill-conditioned in the experiments. To solve this unstable solution problem, regularization techniques are generally used. In this paper, we describe the effective determination of the optimal regularization parameter in the regularization technique during RPC derivation. A brief mathematical background of RFM is presented, followed by numerical approaches for effective determination of the optimal regularization parameter using the Euler Method. Experiments are performed assuming that a tilted aerial image is taken with a known rigorous sensor. To show the effectiveness, calculation time and RMSE between L-curve method and proposed method is compared.

유전자알고리즘 기반 복수 분류모형 통합에 의한 캐피탈고객의 신용 스코어링 모형 (A credit scoring model of a capital company's customers using genetic algorithm based integration of multiple classifiers)

  • 김갑식
    • 한국컴퓨터정보학회논문지
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    • 제10권6호
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    • pp.279-286
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    • 2005
  • 본 연구에서는 캐피탈시장에서의 고객신용예측을 위한 모형으로 여러 가지 인공신경망(Neural Network) 모형들을 유전자 알고리즘(Genetic Algorithm)을 이용하여 통합한 신용예측모형을 제안하였다. 10개의 학습된 인공신경망 모형들을 유전자알고리즘을 이용하여 종류별로 통합하여 MLP (Multi-Layered Perceptron), Linear, RBF(Radial Basis Function) 세 가지의 대표모델을 얻고 이를 다시 하나의 인공신경망 모델로 통합하였다. 이를 통합되기 이전의 각각의 인공신경망 모형들과 성능을 비교, 분석하여 본 연구에서 제안한 통합모형의 유효성과 통합방법의 타당성을 제시하였다.

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Ready-Made Garments (RMG) Export Earnings and Economic Development of Bangladesh: Empirical Analysis Using Vector Error Correction Model

  • JIBAN, Abul Jannat;BISWAS, Gautam Kumar;YANG, Shaohua
    • The Journal of Asian Finance, Economics and Business
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    • 제9권10호
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    • pp.29-38
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    • 2022
  • Ready-made Garments (RMG) export earnings, which are almost 80% of the total exports of Bangladesh, have been recognized as one of the main catalysts for the recent development of the country. Therefore, the need to determine whether the RMG export had served as a mechanism for increasing the GDP growth as well as the economic development of the country is topical and pressing. We have applied the Johansen Co-integration test and Vector Error Correction Model (VECM) to reveal the linkage of RMG export earnings and other variables with the GDP growth rate in Bangladesh. Using data from 1990 to 2020 for Bangladesh, we have found long-run as well as short-run associations among RMG Export earnings, Foreign Direct Investment (FDI), and GDP growth. A co-integration among the variables is validated through the Johansen Co-integration test. Moreover, a causal correlation running from RMG export earnings to GDP was revealed by the Granger causality test in the long run. Finally, we estimated impulse response functions to observe the variations of model variables in response to a shock. Our result supports the proposition that RMG export earnings are one of the main growth engines in Bangladesh and this sector leads growth in other sectors also in the long term.