• 한국초전도ㆍ저온공학회논문지
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• 제21권2호
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• pp.45-49
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• 2019

This paper reports comparison between analytic and numerical simulation approaches for calculation of screening current and screening current induced field in a high temperature superconductor magnet. Bean slab model is adopted to calculate screening current and SCF analytically, while the finite element method numerically. A case study of screening current and SCF calculation are conducted with a magnet, a 7 T 68 mm cold-bore multi-width no-insulation GdBCO magnet built and tested by Massachusetts Institute of Technology Francis Bitter Magnet Laboratory. In this study, we assume the magnet is dunked in liquid nitrogen at 77 K. Furthermore, the simulation results are compared in terms of computation time and accuracy. Finally, discussion on the different methods together with the comparison between the calculations and experiment is provided.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송∙미디어공학회 2022년도 추계학술대회
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• pp.26-29
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• 2022

The diffuse sound field plays a crucial role in the perceptual quality of the auralization of virtual scenes. Diffuse Rain is a geometrical scattering model which enables the simulation of diffuse fields that is compatible with acoustic ray tracing, but is often computationally expensive. We develop a novel method that can reduce this cost by rendering the large number of Diffuse Rain data in Ambisonics format. The proposed method is evaluated in a shoebox scene simulation run on MATLAB, in reference to a more faithful method of rendering the Diffuse Rain data ray-by-ray. The EDC and IACC of the binaural output show that the simulated diffuse field can be rendered in Ambisonics with only minimal deviations in energy decay and spatial quality, even with 1^st-order Ambisonics.

• 한국진공학회지
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• 제5권4호
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• pp.278-283
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• 1996

Field terminator를 이용하여 singl path cylindrical mirror analyser를 제작하였다. 먼저 컴퓨터 모의실험을 바탕으로 CMA의 원통형 전극양단에서 fringing field effect를 최소로 하여 log-scale의 등전위면을 그대로 유지하는 terminator의 전압비와 위치 등을 구하였다. 계산된 전압을 직렬로 연결된 금속산화물저항으로 만든 voltage divider로 field terminator에 직접 인가하여 CMA의 fringing field effect를 줄이는 방법으로 개발하였다. 이 방법으로 제작된 CMA의 분해능이 $\Delta$E/E=0.4% 이상임을 확인하였다.

• International Journal of Automotive Technology
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• 제6권4호
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• pp.351-357
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• 2005

Development of a real-time simulation model for high-speed and multibody tracked vehicles is difficult because they involve hundreds of highly nonlinear equations. In the development of a reliable tracked vehicle model for real-time simulation, it is helpful to use an off-line tracked vehicle model developed by considering all the degrees of freedom of each element. This paper presents a step-by-step procedure for the development of a real-time simulation model based on the off-line tracked vehicle model. The road input data, Profile IV, is used for the real time simulation and simulation results are compared with vehicle test results obtained in the military test field. It is noted that the simulation results are quite close to the test results.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 1999년도 춘계학술대회 논문집
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• pp.94-99
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• 1999

In this Paper, the estimation method of painting process in the automobile plant using computer simulation techniques is studied to improve the bottle neck process, the weak point and the productivity. For model and analysis, Promodel is used which is a manufacturing oriented simulation software developed by Promodel corporation in the U.S.A. Firstly the result of the simulation shows that we can obtain capability improvement in the system performance using computer simulation. Secondly, the optimum system specification is decided by comparing reports generated by scenario in simulation program find out the suitable conditions. Finally, the speed of conveyor and a pitch of painting body as the most critical parameters are chosen on the basis of exhaustive field evaluation to study their effects o the capacity of the process. The best alternative condition for the maximum capacity of the process is selected by computer simulation.

• 한국컴퓨터그래픽스학회논문지
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• 제21권5호
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• pp.21-27
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• 2015

본 논문에서는 방송국 그린 스튜디오에 서 있는 연기자와 CG로 표현되는 스페셜 이펙트(물, 불, 연기 등)와의 상호작용을 제공하는 시스템을 제안한다. 기존의 가상 스튜디오는 주로 CG 배경과 연기자 촬영 영상을 정합하는 방법에 초점을 맞추고 있다. 기존의 연구와 달리 본 논문에서는 실제 연기자와 상호작용하는 비주얼 이펙트를 시뮬레이션하는데 집중함으로써 TV 화면에서 새로운 영역을 표현하고자 한다. 연기자 동작에 비주얼 이펙트를 연동하기 위하여 깊이 카메라를 이용하여 연기자 동작을 추출한다. 이를 3차원 벡터 필드로 변환하고 Navier Stokes 방정식의 외력으로 적용하여 물, 불, 연기의 유체를 시뮬레이션한다. 특히, 물의 상호작용을 사실적으로 표현하기 위하여 물에 연동되는 스플레쉬의 상호작용도 함께 시뮬레이션하여 물이 등장하는 비주얼 이펙트의 사실감을 극대화시켰다. TV의 실시간 녹화를 지원하기 위하여 GPU 프로그래밍을 도입하여 VFX의 실시간 상호작용을 지원하는 기능도 추가하였다. 제안된 방법의 유용성은 물, 불, 연기, 바다 속 물고기 떼 등의 VFX 시뮬레이션과 연기자와의 상호작용 실험을 통하여 확인할 수 있었다.

• 대한건축학회연합논문집
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• 제20권6호
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• pp.81-87
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• 2018

In this paper, in order to maximize the input process efficiency of the building energy simulation field, the authors developed the automatic extraction module of spatial information based BIM geometry information. Existing research or software extracts geometry information based on object information, but it can not be used in the field of energy simulation because it is inconsistent with the geometry information of the object constituting the thermal zone of the actual building model. Especially, IFC-based geometry information extraction module is needed to link with other architectural fields from the viewpoint of reuse of building information. The study method is as follows. (1) Grasp the category and attribute information to be extracted for energy simulation and Analyze the IFC structure based on spatial information (2) Design the algorithm for extracting and reprocessing information for energy simulation from IFC file (use programming language Phython) (3) Develop the module that generates a geometry information database based on spatial information using reprocessed information (4) Verify the accuracy of the development module. In this paper, the reprocessed information can be directly used for energy simulation and it can be widely used regardless of the kind of energy simulation software because it is provided in database format. Therefore, it is expected that the energy simulation process efficiency in actual practice can be maximized.

• 대한산업공학회지
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• 제20권4호
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• pp.73-84
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• 1994

Output analysis is one of the most important fields of simulation to achieve the accurate simulation results. This study shows how to analyze simulation output data in the steady state using Procrustes analysis technique which has not been used in the field of simulation yet. In this paper Procrustes analysis method is used to perform the analysis of simulation output efficiently and effectively by applying the improved version of the method. The experiments are conducted using M/M/1 queueing simulation model. The results obtained by Procrustes analysis method show better estimates for average waiting times and average queue lengths which are closer to true values and narrower confidence intervals than when replication-deletion method is used. Also it requires the smaller number of simulation runs.

• 설비공학논문집
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• 제18권2호
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• pp.112-121
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• 2006

To evaluate the performance of ventilation system properly, the correlations among the ventilation rate, indoor air-quality and cooling/heating load should be analysed. In this study, simulation tool to analyze the performance of ventilation system was developed. The simulation tool is based on the TRNSYS and some modules to calculate concentration of pollutants with the operation of ventilation system and to decide the signal of ventilation system were newly developed in this study. And these modules coupled with building load and heating/cooling simulation modules. To verify the validity of developed simulation tool, comparison study between simulation and field study were accomplished. As results, the simulation tool developed in this study can be used to predict the performance of ventilation system with accuracy.

• 한국시뮬레이션학회논문지
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• 제8권2호
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• pp.73-85
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• 1999

In this paper, the productivity estimation of the painting line in an automobile plant is studied. To improve the bottleneck and the weak point of the process, computer simulations are performed. In determining the system specification, the status of the conveyor lines and the other physical facilities are considered in order not to intervene with each other and to satisfy the painting facility restrictions. As simulation parameters, production performance ratio, number of hanger and dolley, down time, speed of conveyor and the pitch of a painting body are chosen on the basis of exhaustive field evaluation to study their effects on the capacity of the process. The results of the simulation show that we can improve the capability of they system without additional investment to the plant facility. The best condition for the maximum capacity of the process is selected by comparing the alternative computer simulation results. As a simulation language, Promodel is used which is very useful and easy to use in manufacturing oriented simulation.