• Journal of the Korean Physical Society
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• 제73권10호
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• pp.1466-1472
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• 2018

A key comparison has been made between the air-kerma standards of the National Institute of Metrology (NIM), China, and other Asia Pacific Metrology Programme (APMP) members in the medium-energy X-ray. This paper reviews the primary standard Free-air ionization chamber correction factor experimental method and Monte Carlo simulation method in the NIM. The experimental method and the Monte Carlo simulation method are adopted to obtain the correction factor for the medium-energy X-ray primary standard free-air ionization chamber at 100 kV, 135 kV, 180 kV, 250 kV four CCRI reference qualities. The correction factor has already been submitted to the APMP as key comparison data and the results are in good agreement with those obtained in previous studies. This study shows that the experimental method and the EGSnrc simulation method are usually used in the measurement of the correction factor. In particular, the application of the simulation methods is more common.

• 한국CDE학회논문집
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• 제13권4호
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• pp.296-304
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• 2008

Recently, various attempts are being done to apply off-line programming system to field of paint robot. But most commercial simulation softwares have problems that are slow simulation speed and not support various painting paramenters on simulation. This paper proposes enhanced paint simulation method for off-line programming system. For these, this method used the mathematical model of flux field from a previous research. The flux field has the flux distribution function, which reflects on the feature of paint spray. A previous research derived this flux distribution function for an integral function and calculated paint thickness function for an integral function. But if flux distribution function is defined as an integral function, it is inadequate to use for real-time simulation because a number of calculation is needed for estimation of paint thickness distribution. Therefore, we defined the flux distribution function by numerical method for reducing a mount of calculation for estimation of paint thickness. We derived the equation of paint thickness function analytically for reducing a mount of calculation from the paint distribution function defined by numerical method. In order to prove proposed paint simulation method this paper compares the simulated and measured thickness. From this comparison this paper show that paint thickness distribution is predicted precisely by proposed spray paint simulation process.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2006년도 PARALLEL CFD 2006
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• pp.21-26
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• 2006

A large-scale finite element simulation and modeling method is presented for environmental flows in urban area. Parallel stabilized finite element method based on domain decomposition method is employed for the numerical simulation. Several GIS and CAD data are used for the preparation of the shape model for landform and urban structures. The present method Is applied to the simulation of flood flow and wind flow In urban area. The present method is shown to be a useful planning and design tool for the natural disasters and the change of environments in urban area.

• 한국시뮬레이션학회논문지
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• 제9권3호
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• pp.43-51
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• 2000

In regression model, we estimate the unknown parameters by using various methods. There are the least squares method which is the most general, the least absolute deviation method, the regression quantile method and the asymmetric least squares method. In this paper, we will compare each others with two cases: firstly the theoretical comparison in the asymptotic sense and then the practical comparison using Monte Carlo simulation for a small sample size.

• 한국대기환경학회지
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• 제33권6호
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• pp.583-592
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• 2017

A method is proposed for locating the heat sources from temperature observations, and its applicability is investigated for urban thermal environment simulations. A Lagrangian particle dispersion model, which is originally built for simulating the pollutants spread in the air, is exploited to identify the heat sources by transporting the Lagrangian heat particles backwards in time. The urban wind fields are estimated using a diagnostic meteorological model incorporating the morphological model for the urban canopy. The proposed method is tested for the horizontally homogeneous urban boundary layer problems. The effects of the turbulence levels and the computational time on the simulation are investigated.

• 패션비즈니스
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• 제15권3호
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• pp.97-111
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• 2011

This study aims to apply 3D virtual fabric parameters - as obtained from previous research experiments - to 3D virtual clothing simulation in comparing its similarity with actual clothing as worn, with a view to verifying the objectivity and validity of the 3D virtual fabric simulation method devised by the drape image analysis method. In addition, the result is intended to be used as the basic data for new 3D virtual clothing simulation methods. As the results, 3D virtual fabric parameters designed to simulate 3D drape to be similar to actual fabrics were found to be Bending Strength, Buckling Point, Density, Particle Distance, and Shear. They were also found to be important measurements when evaluating visual similarity between drape shadow images and number of nodes. 3D virtual fabric simulation method devised by the drape image analysis method was appropriate in extracting 3D fabric parameters with the reflection of actual fabrics' physical and dynamic characteristics, in connection with 3D virtual fabric simulation. 3D virtual fabric parameters with the reflection of actual fabrics' physical and dynamic characteristics using the proposed 3D virtual fabric simulation method are accumulated and provided as a standard, this will facilitate the introduction 3D virtual fabric simulation technology.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2008년도 정기 학술대회
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• pp.442-445
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• 2008

The purpose of this study is making Proto-type development of BIM based Architectural Construction Simulation System. This study suggest a new schedule access method for overcoming limitation of current Simulation Program focused on visualization. The method made from analysis of current Simulation Program. This program is based on Visual Basic .Net language.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.309-312
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• 2002

For the purpose of more effective simulation of the utility interactive WPGS(Wind Power Generation System) the SWRW (Simulation method for WPGS using Real Weather condition) is used in this paper, in which those of three topics for the WPGS simulation. user-friendly method, applicability to grid-connection and the utilization of the real weather conditions, are satisfied. The simulation of the WPGS using the real weather condition including components modeling of wind turbine system is achieved by introducing the interface method of a non-linear external parameter and FORTRAN using PSCAD/EMTDC. The simulations of steady-state and transient-state are performed effectively by the introduced simulation method. The generator output and current supplied into utility can be obtained by the steady-state simulation, and THD can be achieved by analyzing the results as well. The transient - state of the WPGS can be analyzed by the simulation results of over cut-out wind speed.

• 한국철도학회논문집
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• 제10권3호
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• pp.306-312
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• 2007

This paper presents the optimal design method of the train repair facility based on the simulation analysis. The train is divided into the power car, motorized car and passenger car for the simulation process analysis and train repair facility is composed of each subsystems such as a blast, dry and wash workshop. In simulation analysis, we consider the critical (dependent) factors and design (independent) factors for the optimal design. Therefore, a simulation optimization uses Evolution Strategy (ES) in order to find the optimal design factors. Experimental results indicate that simulation design factors are sufficient to satisfy the conditions of dependent variables. The proposed analysis method demonstrates that simulation design factors determined by the simulation optimization are appropriate for real design factors in a real situation and the accuracy and confidence for the simulation results are increased.

• 한국시뮬레이션학회논문지
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• 제14권3호
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• pp.129-136
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• 2005

We develop a variance reduction technique applicable in one simulation experiment whose purpose is to estimate the parameters of a first order linear model. This method utilizes the control variates obtained during the course of simulation run under Schruben and Margolin's method (S-M method). The performance of this method is shown to be similar in estimating the main effects, and to be superior to S-M method in estimating the overall mean response in a given model. We consider that a proposed method may yield a better result than S-M method if selected control variates are highly correlated with the response at each design point.