• 제목/요약/키워드: Models and Theories

검색결과 403건 처리시간 0.026초

해류발전 로터의 개발 (Development of Current Generation Rotor)

  • 조철희;김경수;민경훈;정광식
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2002년도 춘계학술대회 논문집
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    • pp.75-79
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    • 2002
  • In this research, a design guideline of current generating rotor and acceptable field rotor in offshore environment is proposed. To design rotor model, wind mill rotor design principles and turbine theories were applied based on a field rotor experimental data. To verify the compatibility of the rotor design method and to analyze the properties of design factors, 3 rotor models were designed and experimented in a circular water channel. Three rotor models were designed according to different blade numbers and blade shapes. With various flow velocities and rotor rpm, the rotor power and efficiency were measured and the properties of rotor were estimated. The results can be effectively applied to the design of current generation rotor.

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수평축 해류발전 로터의 설계와 성능해석 (Study on HAT Current Generation Rotor)

  • 조철희;김경수;민경훈;양태열;이현상
    • 한국해양공학회지
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    • 제16권1호
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    • pp.58-63
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    • 2002
  • In this research, a design guideline of current generating HAT rotor and acceptable field rotor in offshore environment is proposed. To design HAT rotor model, wind mill rotor design principles and turbine theories were applied based on a field HAT rotor experimental data. To verify the compatibility of the rotor design method and to analyze the properties of design factors, 3 rotor models were designed and experimented in a circular water channel. Three rotor models were designed according to different blade numbers and blade shapes. By changing flow velocity, rotor rpm, the rotor power and efficiency were measured and the properties of rotor were estimated. The results can be effectively applied to the design of current generation rotor.

Developing a Model to Explain the Process of Technology Transfer at Entrepreneurial University

  • Soleimani, Mohsen;Tabriz, Akbar Alem;Shavarini, Sohrab Khalili
    • Industrial Engineering and Management Systems
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    • 제15권4호
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    • pp.298-306
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    • 2016
  • The gap between universities, scientific centers and industrial-production units is one of higher education concerns. In academic entrepreneurship, the university work simultaneously in education, research and entrepreneurship. The universities play a key and important role in providing educational opportunities in economic development. This research aims to develop and expand science as well as help managers to explain the process of technology transfer in entrepreneurial university. This research is applied-developmental type and on the other hand, data driven theories have been used in this study. Current model is generally tried to meanwhile compensate previous shortcomings, include some strengths such as considering domestic factors of Iran as well as update effective factors on the process of technology transfer. Finally the suggested model has been compared with existing well-known models that each one of those models have some drawbacks which have been tried to be minimized in suggested model as much as possible.

공진 주파수 측정방법을 이용한 Coplanar Waveguide 용량성 불연속 구조 설계 (Modeling of Capacitive Coplanar Waveguide Discontinuities Characterized with a Resonance Method)

  • 김동영;지용
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 하계종합학술대회 논문집(2)
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    • pp.181-184
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    • 2001
  • A coplanar waveguide(CPW) on a dielectric substrate consists of a center strip conductor with semi-infinite ground planes on either side. This type of waveguide offers several advantages over microstrip line. It facilitates easy shunt as well as series mounting of active and passive devices. It eliminates the need for wraparound and via holes, and it has a low radiation loss. These, as well as several other advantages, make CPW ideally suited for microwave integrated circuit applications. However, very little information is available in the literature on models for CPW discontinuities. This lack of sufficient discontinuity models for CPW has limited the application of CPW in microwave circuit design. We presented for the characteristics of coplanar waveguide open end capacitance and series gap capacitance. Measurements by utilizing the resonance method were made and the experimental data confirmed the validity of theories. The relationships between the CPW capacitances and the physical dimensions were studied.

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경제성장에 대한 본원적 구조와 지속가능 내생적 성장이론에 대한 시스템 다이내믹스 모델링 (System Dynamics Modeling for the Generic Structure of Economic Growth and the Sustainable Endogenous Growth Theory)

  • 전대욱;김지수
    • 한국시스템다이내믹스연구
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    • 제10권1호
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    • pp.5-32
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    • 2009
  • This paper revisited the key advances on System Dynamics modeling about traditional macro-economic models and economic growth structures, and then tries to elaborate a new model based on the endogenous growth theory that incorporates new growth factors, relevant to knowledge/technology as well as the Environment, into traditional growth models. Accordingly, the new model augments the acceleration and multiplier loops and the balancing ones representing market clearing mechanism with a simple numerical example. The authors thus provides macroeconomic System Dynamics analysts with a milestone to model macro-economic structures reflecting on traditional and cutting-edge theories on sustainable economic growth and general equilibrium modeling.

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Preservice Biology Teachers' Learning to Teach Science through Science Methods Courses

  • Kim, Sun Young
    • 한국과학교육학회지
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    • 제32권9호
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    • pp.1427-1442
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    • 2012
  • This study tracked the changes of preservice biology teachers' pedagogical knowledge along with science teaching efficacy throughout sequentially developed science methods course I and II over two consecutive semesters. Two courses, science methods course I and II, aimed these preservice teachers to discuss the notion of science teaching with teaching and learning theories, to learn science instructional models, to design lessons utilizing science instructional models, and to eventually implement microteaching. The preservice teachers were mainly engaged in cooperative instructional planning activities through science methods course I, and engaged in cooperative microteaching activities through the science methods course II. This study revealed that preservice teachers successfully developed pedagogical knowledge and science teaching efficacy after two science methods courses. The science methods course I where cooperative instructional planning activities occurred helped the preservice teachers to improve pedagogical knowledge but not science teaching efficacy. Based on their pedagogical knowledge development, then, these preservice teachers increased science teaching efficacy belief after completion of the science methods course II.

A Selective Induction Framework for Improving Prediction in Financial Markets

  • Kim, Sung Kun
    • Journal of Information Technology Applications and Management
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    • 제22권3호
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    • pp.1-18
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    • 2015
  • Financial markets are characterized by large numbers of complex and interacting factors which are ill-understood and frequently difficult to measure. Mathematical models developed in finance are precise formulations of theories of how these factors interact to produce the market value of financial asset. While these models are quite good at predicting these market values, because these forces and their interactions are not precisely understood, the model value nevertheless deviates to some extent from the observable market value. In this paper we propose a framework for augmenting the predictive capabilities of mathematical model with a learning component which is primed with an initial set of historical data and then adjusts its behavior after the event of prediction.

위험물 취급설비 화재 사고결과 영향평가 프로그램 개발 방향 (Development Direction of Fire Consequence Analysis Programs for Hazardous Materials)

  • 유재환;김용수;이영순;이경봉;이성우;박달재
    • 한국화재소방학회논문지
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    • 제13권4호
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    • pp.1-6
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    • 1999
  • 본 연구에서는 위험물 취급설비에 대하여 4가지 화재유형으로 나누어 사고 시나리오를 작성하였다. 그리고 작성된 시나리오를 바탕으로 SuperChems Pro., 3.1, SAFER Trace Ver., 8.2, PHAST Pro., Ver., 5.2 등 외국의 사고결과 영향평가 프로그램을 이용하여 사고결과 영향평가 프로그램의 적용 특성을 분석·평가하였으며 이들 프로그램의 분석, 적용 평가 결과 및 관련이론을 활용하여 이를 전산화 할 수 있는 화재모델 및 서브모델을 선정하여 제시하였다.

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홈네트워크 산업의 비즈니스 모델과 전략적 제휴 : 분석과 제안 (A Study on Business Models and Strategic Alliance : An Analysis and Suggestion)

  • 이희상;한현수;노승종
    • 경영과학
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    • 제23권3호
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    • pp.157-182
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    • 2006
  • Increasing attention has been paid to the home network business in Korea. The rate of growth of the business, however, has not been as high as it was expected. In this study we first categorize the business into three classes of services, with five distinct players. The business models of the five players differ from each other, which in turn keeps the business from visible growth. Based on this observation, we applied business alliance theories to the home network business to find out ways to make the players cooperate with each other. And we proposed five cooperation strategies for three different classes of home network services. Finally we made some suggestions to remove obstacles against business cooperation among the players.

강화학습 기반의 다단계 공급망 분배계획 (Reinforcement leaning based multi-echelon supply chain distribution planning)

  • 권익현
    • 대한안전경영과학회지
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    • 제16권4호
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    • pp.323-330
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    • 2014
  • Various inventory control theories have tried to modelling and analyzing supply chains by using quantitative methods and characterization of optimal control policies. However, despite of various efforts in this research filed, the existing models cannot afford to be applied to the realistic problems. The most unrealistic assumption for these models is customer demand. Most of previous researches assume that the customer demand is stationary with a known distribution, whereas, in reality, the customer demand is not known a priori and changes over time. In this paper, we propose a reinforcement learning based adaptive echelon base-stock inventory control policy for a multi-stage, serial supply chain with non-stationary customer demand under the service level constraint. Using various simulation experiments, we prove that the proposed inventory control policy can meet the target service level quite well under various experimental environments.