• 산업경영시스템학회지
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• 제44권4호
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• pp.113-127
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• 2021

Topic modeling has been receiving much attention in academic disciplines in recent years. Topic modeling is one of the applications in machine learning and natural language processing. It is a statistical modeling procedure to discover topics in the collection of documents. Recently, there have been many attempts to find out topics in diverse fields of academic research. Although the first Department of Industrial Engineering (I.E.) was established in Hanyang university in 1958, Korean Institute of Industrial Engineers (KIIE) which is truly the most academic society was first founded to contribute to research for I.E. and promote industrial techniques in 1974. Korean Society of Industrial and Systems Engineering (KSIE) was established four years later. However, the research topics for KSIE journal have not been deeply examined up until now. Using topic modeling algorithms, we cautiously aim to detect the research topics of KSIE journal for the first half of the society history, from 1978 to 1999. We made use of titles and abstracts in research papers to find out topics in KSIE journal by conducting four algorithms, LSA, HDP, LDA, and LDA Mallet. Topic analysis results obtained by the algorithms were compared. We tried to show the whole procedure of topic analysis in detail for further practical use in future. We employed visualization techniques by using analysis result obtained from LDA. As a result of thorough analysis of topic modeling, eight major research topics were discovered including Production/Logistics/Inventory, Reliability, Quality, Probability/Statistics, Management Engineering/Industry, Engineering Economy, Human Factor/Safety/Computer/Information Technology, and Heuristics/Optimization.

• 한국군사과학기술학회지
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• 제14권2호
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• pp.173-180
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• 2011

SRMD system which protects MBT from the threats in a short range is composed of 2 radars, 2 IRTs 1 CCU and 2 countermeasures. To analyze the performance of this system, there is a need to make the model of MBT on which this system is loaded. In this paper, a method of MBT movement modeling is proposed to fulfill the above need. The methods of the coordinate system transformation among the components and the modeling of a hull's traveling and a turret's turning are proposed. The method of the modeling of a pose variation caused by the vibrations is proposed and the results of the modeling are presented.

• 산업기술연구
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• 제31권B호
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• pp.81-90
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• 2011

Centrifuge modeling and numerical analysis on works of breakwater construction were performed to investigate the behavior of caisson type of breakwater and foundation treated with the method of DCM (Deep Cement Mixing) under the condition of wave action in field. In centrifuge modeling, construction sequence of breakwater caisson such as preparation of ground, treatment of DCM, installation of rubble mound, placement of breakwater caisson and lateral loading on the breakwater due to wave action were reconstructed. Lateral movement of model breakwater and ground reaction in the vertical direction were monitored during test. Stress concentration ratio between the untreated ground and the treated ground with DCM was evaluated from measurement of vertical stresses on each ground. Numerical analysis with the software of PLAXIS was carried to compare with Results of centrifuge model test. It was found that stability of model breakwater was maintained during stage of construction and the compared results about stress concentration ratio were in relatively good agreements.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2005년도 춘계 학술대회논문집
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• pp.91-95
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• 2005

A heat dissipation modeling method of EEE parts is developed for thermal design and analysis of an satellite electronic equipment. The power consumption measurement value of each functional breadboard is used for the heat dissipation modeling method. For the purpose of conduction heat transfer modeling of EEE parts, surface heat model using very thin ignorable thermal plates is developed instead of conventional lumped capacity nodes. The thermal plates are projected to the printed circuit board and can be modeled and modified easily by numerically preprocessing programs according to design changes. These modeling methods are applied to the thermal design and analysis of CTU and verified by thermal cycling and vacuum tests.

• 한국정밀공학회지
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• 제20권2호
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• pp.209-217
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• 2003

In this paper, the dynamic system modeling and the state sensitivity analysis of the spin-coater system are proposed for the reduction of the vibration. In the respect of modeling, the spin-coater system is considered to be composed of servomotor, spindle, supporting base and so on. Each component of model is combined and derived to 3 dimensional equations. The combined model is verified by experimental values of actual system in the frequency domain. By direct differentiation of the constraint equations with respect to kinematic design variables, such as eccentricity of spindle, moment of inertia, rotational stiffness and damping of supported base, sensitivity equations are derived to the verified state equations. Sensitivity of design variables could be used for vibration reduction and natural frequency shift in the frequency domain. Finally, dominant design variables are selected from the sensitivity analysis.

• 소음진동
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• 제2권2호
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• pp.125-134
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• 1992

In this study, ti identify the dynamic characteristics of automobile steering system which consists of many components and joints, each component combined structure was analyzed using commercial structural package, ANSYS. And, the finite element method for each component and modeling method of several joints universal joint, bolt joint, bearing, etc. were studied. On the other hand, the experimental modal analysis was performed to compare with the results of the finite element analysis and joint modeling. The result shows very close agreement between two analysis. Also, it was found that the steeing column used in this experiment does not effect the low frequency mode of entire system. In addition, we found that constraint equations need to be considered in modeling universal joint. Since the stiffness effect of Urethane around wheel could be ignored, it can be modeled only with mass effect. In the end, it was found that dynamic characteristics of the entire steerintg system depends mainly upon the wheel characteristics.

• 한국항공우주학회지
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• 제31권1호
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• pp.67-72
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• 2003

본 논문에서는 다목적실용위성 1호의 태양전지를 모델링하고 해석하였다. 태양전지판의 모델링은 적은 수의 데이터만을 갖고 있으므로 비선형 시스템을 모델링하는 데 적합한 누럴 알고리즘을 사용하였다. 모델링 결과는 다목적실용위성 1호의 태양전지 셀 데이터를 고려한 태양전지판의 해석과 시뮬레이션에 의해 그 특성을 증명하였다. 또한, 태양전지판의 특성 및 전력발생 특성은 모델링 결과를 사용하여 해석하였다

• 한국연소학회:학술대회논문집
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• 한국연소학회 2013년도 제46회 KOSCO SYMPOSIUM 초록집
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• pp.59-60
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• 2013

Rotary kiln furnace is one of the most widely used gas-solid reactors in the industrial field. Although the rotary kiln is a versatile system and has different size, approach to the reactor modeling can be generalized in terms of flow motion of the solid and gas phase, heat transfer and chemical reactions on purpose. In this paper, a performance analysis example case of axial direction direct flame rotary kiln is introduced.

• 대한기계학회논문집B
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• 제26권6호
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• pp.875-882
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• 2002

The modeling for turbulent flow through a porous media has not been confirmed because of a undetermined constant which appears in the governing equations. In present study, the turbulent porous modeling based on the local thermal equilibrium has been extended to the turbulent clear flow. A undetermined constant is also suggested by microscopic analysis. The microscopic analysis is performed in the flat tube with micro-channels, and it confirms that the undetermined constant is 0.99. It is shown that the results of the macroscopic analysis using confirmed constant agree well with those of the microscopic analysis with a maximum error of 3.5%.

• 대한기계학회논문집B
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• 제23권9호
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• pp.1129-1138
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• 1999

This paper presents a systematic two-zone modeling for reliable performance prediction of centrifugal compressors. In order to improve the predictive capability, a modified jet slip factor is developed and new corrections for the wake flow deviation and mass fraction are suggested based on the comprehensive experimental data of the three Eckardt impellers. The proposed two-zone modeling is tested against nine sets of measured data of centrifugal compressors. The results are also compared with those obtained by the mean streamline analysis. It was found that the predictions by the present two-zone modeling agree fairly well with experimental data for a variety of centrifugal compressors over the wide operating conditions.