• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2008년도 추계학술대회 및 정기총회
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• pp.444-447
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• 2008

This study is intended to develop a improved version of Cross Impact Analysis Model based on Scaling Theory. In developing the model, we applied the scale transformation technique and regression technique to existing CIA model. Improved CIA model is composed of two sub-models: 'model for impact value measurement,' and 'model for impact value conversion'. We applied a technique which measures data by ordinal scale and then transforms them into interval scale and ratio scale data to CIA model. The accuracy of forecasting and the usability of CIA application have been improved.

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 2001년도 제19회 하계학술발표회 논문집
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• pp.61-70
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• 2001

Cross impact relationships exist among technologies. The purpose of this study is to develop a Cross Impact-based Technology Valuation Model necessary for evaluating the value of interdependent technology. For this purpose, cross impact relationships among interdependent technologies within specific technological system are analyzed by using Fuzzy Structural Modeling(FSM) Method. The model developed in this study will be a useful means of strategic decision making for companies which transact technologies.

• 환경영향평가
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• 제32권2호
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• pp.61-71
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• 2023

공간 스케일에 따른 생물 종 별 영향의 차이가 발생함에 따라, 도시 개발 사업에 따른 영향을 정량적으로 평가하기 위해서는 경관규모에서의 분석이 필요하다. 선행연구에서는 도시개발에 따라 변화하는 환경에 대한 생물종 영향을 분석하기위해 메타개체군 이론을 기반한 Incidence Function Model (IFM)을 활용하여 분석하고 있다. 하지만 해당 모델은 최소 점유영역이 10개 이상이 되어야 하므로, 모니터링이 어려운 생물종에 대한 활용은 어렵다. 따라서 본 연구에서는 이러한 문제점을 보완하기 위해 삵(Prionailurus bengalensis)을 중심으로 종 분포 모델을 통해 구축된 데이터를 바탕으로 IFM 모델을 분석하고자 하였다. 또한, 본 모델을 통해 환경영향평가서 중 자연생태환경분야에서의 활용 가능성을 검토하였다. 연구결과, 도시개발에 따른 삵의 최소 점유율은 56.5%, 생존가능성은 28.7%로 감소하는 것을 확인할 수 있었다. 서식지 개수 감소에 따른 개체군 수용력에 대한 분석을 통해 230개소와 70개소에서 개체군의 수용 능력이 급격하게 감소함을 확인하였다. 본 연구는 환경계획 관점에서 서식지 면적 감소에 따른 삵의 환경영향을 평가하였으며, 삵을 보호하기 위한 최소한의 서식지 개수 및 면적 설정에 대한 의사결정을 지원할 수 있다. 이는 개발 프로젝트 전, 후 영향평가 및 저감방안 계획에 기초자료로 활용됨으로써, 저감방안의 실효성을 높여줄 수 있을 것으로 기대된다.

• 대한기계학회논문집
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• 제18권3호
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• pp.600-611
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• 1994

The purpose of this research is to propose a model for the prediction of residual strength. For this purpose, two-paremeter model based on Caprino's is developed and formulated by the ratio of indentation due to impact and normalized residual strength. The damage zone is considered only as an indentation. Impact tests are carried out on laminated composites by steel balls. Test material is carbon/epoxy laminate. The specimens are composed of $[{\pm}45^{\circ}/0^{\circ}/90^{\circ}]_2$ and $[\pm}45^{\circ}]_4$ stacking sequence and have $0.75^T{\times}0.26^W{\times}100^L(mm) dimension. A proposed model shows a good correlation with the experimental results And failure mechanism due to high impact velocity is discussed on CFRP laminates to examine the initiation and development of damage by fractography and ultrasonic image ststem. The effect of the unidirectional ply position on the residual strength is considered here.

• 한국자동차공학회논문집
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• 제6권2호
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• pp.178-190
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• 1998

We have developed a planar impact model with a capability of reverse calculation to reconstruct various types of automobile collisions. This topic is the main part of what is referred to as accident reconstruction. The model uses the principle of impulse and momentum, and introduces a restitution coefficient and an impulse ratio at the impact center. Based on the car-to-car collision test results, we present how to estimate the restitution coefficient and the impulse ratio from some impact conditions. To validate the model and improve its reliability in accident analysis, the collision analysis has been performer with the estimated parameters. The analysis and experimental results agree well in the kinetic energy loss and the post-impact velocity.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문집
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• pp.719-724
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• 2002

Impact hammer is widely used as a convenient excitation tool in structural modal testing though, little is known about the dynamic characteristics of its impulse mechanism. Transmission of the impulsive force to the structure depends m the dynamic properties of the impact hammer as well as the stiffness of the tip. In this study an improved dynamic model of the impact hammer is proposed with the consideration of structure to be tested. The deformation masses of hammer tip and structure are as well as their contact stiffness. Numerical results show that this model is useful for the prediction of the impulse duration and the condition of rebounce..

• 한국경영과학회지
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• 제8권2호
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• pp.9-25
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• 1983

A new approach to cross impact analysis using probabilistic system dynamics(PSD) is presented in this article. The previous models using PSD consist of system dynamics models as a basis which are interacting with cross impact analysis (CIA) sectors. In this model, the policy impact analysis part is separated from the CIA sectors and is constituted an independent subsectors of the model. The policy subsector is designed to separate the policy impact and provide feedback both to the system dynamics base model and cross impact analysis sectors. The new technique is applied to the forecasting, assessment and policy formulation of air pollution in Seoul metropolitan area in 2,000. The results show that the new tool consider policy effects more effectively than the previous PSD models.

• 대한기계학회논문집
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• 제19권3호
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• pp.623-630
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• 1995

The impulse response functions (force-strain relations) for Euler-Bernoulli and Timoshenko beams are considered. The response of a beam to a transverse impact force is numerically obtained with the convolution approach using the impulse response function obtained by Laplace transform. Using this relation, the impact force history is determined in the time domain and results are compared with those from Hertz's contact law. The parameters of timpact force model are identified using the recovered force and compared with the Hertz's contact model. In order to verify the proposed algorithm, measurements were done using an impact hammer and a steel ball drop test and these results are also compared with the simulated values.

• 한국해양공학회지
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• 제29권2호
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• pp.163-168
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• 2015

This paper presents the results of experimental work on the wedge slamming impact problem. An experiment was done with a wedge model. The deadrise angle of the wedge was $4^{\circ}$. The model was made in two parts: the outside part was made of a 5-mm-thick steel plate that could be assumed to be a rigid body, and the inside part was made of a thin SUS plate that could be assumed to be an elastic body. Thin SUS plate thicknesses of 2 mm and 3 mm were used to determine the effect of plate rigidity. The drop height was varied from 0.25 m to 1 m to determine the effect of a large deformation.

• 환경영향평가
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• 제20권3호
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• pp.337-348
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• 2011

Urban environmental problem became one of major issues during its urbanization processes. Environmental impacts are assessed during recent urban planning and development. Though the environmental impact assessment considers meteorological impact as a minor component, changes in wind environment during development can largely affect the distribution pattern of air temperature, humidity, and pollutants. Impact assessment of local wind is, therefore, a major element for impact assessment prior to any other meteorological impact assessment. Computational Fluid Dynamics (CFD) models are utilized in various fields such as in wind field assessment during a construction of a new building and in post analysis of a fire event over a mountain. CFD models require specially formatted input data and produce specific output files, which can be analyzed using special programs. CFD's huge requirement in computing power is another hurdle in practical use. In this study, a CFD model and related software processors were automated and integrated as a microscale wind environmental impact assessment system. A supercomputer system was used to reduce the running hours of the model. Input data processor ingests development plans in CAD or GIS formatted files and produces input data files for the CFD model. Output data processor produces various analytical graphs upon user requests. The system was used in assessing the impacts of a new building near an observatory on wind fields and showed the changes by the construction visually and quantitatively. The microscale wind assessment system will evolve, of course, incorporating new improvement of the models and processors. Nevertheless the framework suggested here can be utilized as a basic system for the assessment.