• 한국음향학회지
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• 제9권3호
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• pp.56-61
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• 1990

수중폭발음의 Energy spectrum 분석에 보다 정밀한 이론적 뒷받침을 하기 위하여 폭발음의 파형에 Gaussian formula를 도입하였으며 이 파형에 따른 Energy spectrum 모델을 새로이 유도하였다. Impulse formula를 이용한 Weston 모델이 낮은 폭발 에너지나 음원의 작동수심이 깊을 경우 이론적 모델로서 한계성을 갖는데 비해 이 모델은 이러한 조건에서도 실험결과와 잘 일치되고 있음을 확인할 수 있었다.

• 한국콘텐츠학회논문지
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• 제6권8호
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• pp.85-93
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• 2006

최근 들어, IT 행동과 관련된 연구가 진행되었음에도 불구하고 수용자의 유형에 따라 행동이 어떻게 달라지는지 파악한 연구는 거의 없다. 본 연구는 모바일 인터넷 서비스를 대상으로 수용자의 유형에 따라 수용 후 행동이 어떻게 달라지는지 검증하고자 한다. 이를 위해, 본 연구에서는 사용 지속 모델을 이용하였고, 이 모델을 기반으로 두 집단 간의 행동 차이를 검증하였다. 연구 결과, 두 집단 간의 IT 행동은 각각 다르게 나타났다. 본 연구의 결과는 이론적인 의의와 실용적인 의의 점을 제공하고 있다.

• Tribology and Lubricants
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• 제13권4호
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• pp.1-9
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• 1997

ER clutch is a device using ER fluid, so called "intelligent material" and is a power transmission system controlled with electric field strength. In this paper(Part III), the behavior of ER clutch under proper conditions was investigated experimentally and compared to theoretical analyses developed from Part I, II. Considering the optimum design concept proposed from Part I, the concentric cylinder type of ER clutch was designed and the experimental apparatus for the performance test was constructed. The comparisons made indicated that the power transmission model of ER clutch and the temperature rise model of ER fluid developed from Part I, II were acceptable for engineering design calculations.culations.

• KDI Journal of Economic Policy
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• 제29권1호
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• pp.113-136
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• 2007

우리나라 주택가격은 2001년 이후 빠르게 상승하는 모습을 보이고 있어 주택가격의 급등에 대한 우려가 높다. 본 연구에서는 우리나라의 주택가격을 주택시장 수급의 장기균형모형, 현재가치모형 및 일반 균형자산 가격모형 등의 이론적 자산가격모형을 이용하여 분석하고 이에 따르는 시사점을 모색하였다. 분석결과 주택가격이 경제의 기초적인 여건을 반영한 균형가격보다 전반적으로 높게 나타나 주택가격의 안정화를 위한 노력이 필요한 것으로 판단된다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 춘계학술대회논문집
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• pp.601-606
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• 2004

This paper deals with friction-induced vibration of disc brake system under constant friction coefficient. A linear, lumped and distributed parameter model to represent the floating caliper disc brake system is proposed. The complex eigenvalues are used to investigate the dynamic stability and in order to verify simulations which are based on the theoretical model, the experimental modal test and the dynamometer test are performed. The comparison of experimental and theoretical results shows a good agreement and the analysis indicates that mode coupling due to friction force is responsible for disc brake squeal. And squeal type instability is investigated by using the parametric analysis. This indicates parameters which have influence on the propensity of brake squeal. This helped to validate the analysis model and establish confidence in the analysis results. Also they may be useful during system development or diagnostic analysis.

• Journal of international Conference on Electrical Machines and Systems
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• 제3권3호
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• pp.325-330
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• 2014

Eddy current induction is used in a wide range of electronic devices, for example in detection sensors. Due to the advances in computer hardware and software, the need for 3D computation and system comprehension is a requirement to develop and optimize such devices nowadays. Pure theoretical models are mostly limited to special cases. On the other hand, the classical use of commercial Finite Element (FE) electromagnetic 3D models is not computationally efficient and lacks modeling flexibility or robustness. The proposed approach focuses on: (1) implementing theoretical formulations in 3D (FE) model of a detection device as well as (2) an automatic Volumetric Estimation Method (VEM) developed to selectively model the target finite elements. Due to these two approaches, this model is suitable for parametric studies and optimization of the number, location, shape, and size of PCB receivers in order to get the desired target discrimination information preserving high accuracy with tenfold reduction in computation time compared to commercial FE software.

• 한국시스템다이내믹스연구
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• 제10권1호
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• pp.33-60
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• 2009

This study explores the limitation in making a causal model through an existing case and proposes an alternative plan to improve a theoretical system of causation modeling. To make a dynamic and actual model, several principles are needed such as reality based analysis of system structures and dynamics, consistent expression of causations, conversion of numerical formulas to causal relations, classification and arrangement of variables by size of concept, etc. However, it is hard to find cases to apply these considerations from existing models in System Dynamics. Therefore, this study verifies errors of derived models from literatures and proposes principles and guides that should be considered to make a sound dynamic model on a causal map. It contributes to making an opportunity for exciting public opinion to improve theory about causal maps, yet it has limitation that the study does not advance forward to the experimental step. For future study, it plans to make up by classifying and leveling causal variables, developing a dynamic BSC model.

• 한국정밀공학회지
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• 제15권3호
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• pp.150-156
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• 1998

In this paper, a 3-DOF(Degree Of Freedom) rigid body model is developed for dynamic analysis of a hydrostatic table. The dynamic coefficients, stiffness and damping constant of each pad are calculated from the mass flow continuity condition. The validity of this model is examined in theoretical and experimental method. The dynamic behavior when mass unbalances and local variations of stiffness and damping of pads present is analyzed for real applications of hydrostatic table. Since the theoretical and experimental results show goof agreement. it can be said that the 3-DOF rigid body model is useful for the dynamic model of the table. The analysis reveals that the pitching motion is the dominant mode of vibration, It also reveals that unbalanced loads can increase amplitude of tilting motion and reduce natural frequencies and damping capacity of the hydrostatic table.

• 한국소음진동공학회논문집
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• 제14권8호
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• pp.702-708
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• 2004

This paper deals with friction-induced vibration of disc brake system under constant friction coefficient. A linear, lumped and distributed parameter model to represent the floating caliper disc brake system is proposed. The complex eigenvalues are used to investigate the dynamic stability and in order to verify simulations which are based on the theoretical model, the experimental modal test and the dynamometer test are performed. The comparison of experimental and theoretical results shows a good agreement and the analysis indicates that mode coupling due to friction force is responsible for disc brake squeal. And squeal type Instability is Investigated by using the parametric analysis. This indicates parameters which have influence on the propensity of brake squeal. This helped to validate the analysis model and establish confidence in the analysis results. Also they may be useful during system development or diagnostic analysis.

• Asian Journal of Innovation and Policy
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• 제1권1호
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• pp.31-49
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• 2012

This paper is a review of a 13-year-old policy for university reform in Korea, the Brain Korea 21 Program, based on current theoretical frameworks. Current theoretical frameworks are classified into three groups: micro and macro perspectives on universities and discussion on world-class universities. The overall purpose of BK21 is to bring up high-level scholarship through manpower and achieve several targets of university reform. The program can be evaluated as a success in terms of following a research university model but not the entrepreneurial university model. However, the fact that a 13-year old policy developed under a research university model had features of the entrepreneurial university shows the direction of change that the research university is currently undergoing.