• Journal of Korean Society of Forest Science
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• v.95 no.2
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• pp.203-208
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• 2006

This study compared the roundwood demand prediction accuracy of econometric and time-series models using Korean data. The roundwood was divided into softwood and hardwood by species. The econometric model of roundwood demand was specified with four explanatory variables; own price, substitute price, gross domestic product, dummy. The time-series model was specified with lagged endogenous variable. The dummy variable reflected the abrupt decrease in roundwood demand in the late 1990's in the case of softwood roundwood, and the boom of plywood export in the late 1970's in the case of hardwood roundwood. On the other hand, the prediction accuracy was estimated on the basis of Residual Mean Square Errors(RMSE). The results showed that the softwood roundwood demand prediction can be performed more accurately by econometric model than by time-series model. However, the hardwood roundwood demand prediction accuracy was similar in the case of using econometric and time-series model.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2002.05a
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• pp.234-239
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• 2002

한국인 인체모델은 동적 환경에서 정면 및 측면 충돌에 대한 지체의 가속도를 얻을 수 있도록 개발되었다. 우선 GEBOD에 입력하기 위한 32개의 한국인 인체치수를 선별하고, 15개의 지체를 가진 한국인 인체모델을 구성한다. 손 동작의 감성평가에 이용하기 위해 손을 독립된 지체로 분리한 17개 지체의 인체모델을 완성한다. MADYMO를 통한 정면충돌 테스트에서는 Hybrid III에 비해 한국인의 머리와 흉부 가속도가 비교적 높게 나왔고, 측면충돌 테스트에서 흉추 1번의 가속도는 ISO에서 요구하는 범위의 상한값을 조금 벗어나는 결과를 얻었다.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2002.05a
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• pp.240-243
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• 2002

본 연구에서는 인간공학적 평가를 위한 한국인 인체모델을 개발하고, 인체 모델의 평가를 위해 팔 동작의 시뮬레이션 및 리치 평가를 수행하였다. 한국인의 인체측정자료를 이용하여 통계학적 분석을 실시하고, 인체 자료생성 프로그램을 통해 인체 각 지체들의 특성치와 상관관계를 얻었다. 이를 바탕으로 인체 모델을 구성하고 가상 공간에서의 용이한 적용을 위해 인체 모델은 3차원 그래픽 기술을 통해 가시화되었다. 차량모델과 인체모델을 통합하고 차량 내에서 운전자의 팔 동작 표현 및 리치 평가기능을 구현하였다.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2001.11a
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• pp.173-178
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• 2001

제품 및 환경에 대한 감성평가를 위한 한국인 체형에 맞는 인체모델을 개발하기 위해 인체측정자료를 수집 및 분석한다. 분석된 인체측정 자료를 이용하여 15개의 지체와 14개의 조인트로 구성된 인체모델을 구성하고 기구학적 특성 값을 기술한다. 구성된 인체모델은 3차원 그래픽 기술을 통해 가시화하며, 가상현실 상에서 제품 및 환경과 상호 작용하도록 구성함으로써 감성평가가 가능하도록 구성한다. 정면충돌 상황시의 각 지체의 거동을 분석하고 국제 인체모델과 비교함으로써 동역학적으로 인체모델이 타당한지를 평가한다. 가상환경에서 차량 내부의 감성평가에 인체모델을 이용한다.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2018.05a
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• pp.125-126
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• 2018

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.04a
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• pp.33-39
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• 2003

Injection molding is widely used in producing various plastic parts due to its high productivity and the demand for high precision injection molded products is ever increasing. To achieve successful product quality and precision, the design of gating and runner systems in the injection mold is very important since it directly influences melt flow into the cavity. Some defects such as weld lines and overpacking can be effectively controlled with proper selection of gate locations. In the present study, the design of gate locations in injection molding of a dashboard for automobiles was carried out with CAMPmold, a PC-based simulation system for injection molding. A dummy runner was developed to simulate a runner system in order to increase the efficiency of the analysis. The numbers and locations of gates were varied in the present investigation as that an acceptable design was obtained in terms of reduced maximum pressure and clamping force.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.9
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• pp.203-211
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• 1999

The research committee for automobile repairs (RCAR), an international body of insurance research centers, has adopted the typical low speed crash test based on an average damage level in crash accidents to estimate the damageability , repairability and safety. The characteristics of body acceleration and the probability of injury are investigated based on damaged components, accelerations of body and injured dummy to analyze damageability and the driver's safety under low speed crash environment. It is found from the experimental results that the probability of head and thorax injuries are very low comparing to the injury criteria of FMVSS No.208. Furthermore, it is suggested that the deployment of airbag may not be necessary at RCAR low speed frontal crash test.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.2
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• pp.118-128
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• 1998

Finite element analyses are carried out to provide results usable in the design of airbag module that consists of inflater, cushion, cover, mounting plate, etc. In the first phase, a deployment process of airbag module is analyzed to evaluate the pressure waveform of developed airbag and deployment characteristics, and is compared with the test results. Interaction between head form and inflated airbag module is investigated in the second phase. In the last stage, sled test with rigid dummy, airbag midule, driving system and car interior part are simulated to investigate the influence of airbag design factor on the behavior of dummy with seat belt. The procedures can be provided as a guideline for airbag module design and improvement of airbag module performance.

• The Korean Journal of Applied Statistics
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• v.23 no.4
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• pp.693-703
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• 2010

Diseases of human or economical traits of cattles are occured by interaction of genes. We introduce expanded multifactor dimensionality reduction(E-MDR), dummy multifactor dimensionality reduction(D-MDR) and SNPHarvester which are developed to find interaction of genes. We will select interaction of outstanding gene combinations and select final best genotype groups.

• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.1
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• pp.61-83
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• 2009

This study developed a variable demand traffic assignment model by stable dynamics. Stable dynamics, suggested by Nesterov and do Palma[19], is a new model which describes and provides a stable state of congestion in urban transportation networks. In comparison with the user equilibrium model, which is based on the arc travel time function in analyzing transportation networks, stable dynamics requires few parameters and is coincident with intuitions and observations on congestion. It is therefore expected to be a useful analysis tool for transportation planners. In this study, we generalize the stable dynamics into the model with variable demands. We suggest a three stage optimization model. In the first stage, we introduce critical travel times and dummy links and determine variable demands and link flows by applying an optimization problem to an extended network with the dummy links. Then we determine link travel times and path flows in the following stages. We present a numerical example of the application of the model to a given network.