• 한국정밀공학회지
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• 제19권11호
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• pp.137-145
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• 2002

Electric vehicle body has to be subjected to uniform load and requires auxiliary equipment such as air pipe and electric wire pipe. Especially, the cross beam supports the weight of passenger and electrical equipments. a lightweight vehicle body is salutary to save operating costs and fuel consumption. Therefore this study is to perform the size and the shape optimization of crossbeam for electric vehicle using the method of topology optimization to introduce the concept of homogenization based on optimality criteria method which is efficient for the problem having the number of design variables and a few boundary condition. this provides the method to determine the optimum position and shape of circular hole in the cross beam and then can achieve the optimal design to reduce weight.

• 기술사
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• 제32권2호
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• pp.99-109
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• 1999

The dried sea tangle added for soup prepatation to improved the taste in Korean and Japaness for long time. Attempts were made to develop the best procedures for extraction and removal of alginate by ultrafiltration and diafiltration. The summerized results of this study are as follows: 1) For hot water extraction in temperature range of 60～100$^{\circ}C$ for 4 hours, the higher temperature resulted higher yields in solids and protein. 2) Optimum sea tangle hot water extraction condition were 60～65$^{\circ}C$ for 1 hour which was cheap operating cost and high yield of good taste components. 3) The membrane flux was more higher GR 51 PP. and increase of flow rate permeate flow rate was accordingly increased. but limiting flow volume was 3.7 l/min. 4) It was found that ultration was relatively of higher recovery rate, solid and taste components, and low rejection coefficient rate than diafiltration.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 춘계학술대회 및 기술 세미나 논문집 디스플레이 광소자
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• pp.67-68
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• 2008

A simple bi-layer structure of organic light emitting diode (OLED) was used to study the characteristics of anode preparation. Indium tin oxide (ITO) anode surface treatment of OLEDs was performed to get the optimum condition for the ITO anode. The ITO surface was treated by $O_2$ or $O_2$ / Ar mixed gas plasma with different processing time. The electrical characteristics of OLED were improved by plasma treatment. The operating voltage of OLED with $O_2$ or $O_2$/Ar mixed gas plasma treated anodes decreases from 8.2 to 3.4 V and 3.2V, respectively. The $O_2$ /Ar mixed gas plasma treatment results in better electrical property.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.359-361
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• 2003

본 연구에서는 태양광 발전 시스템용 밀폐형 연축전지(VRLA Valve Regulated Lead Acid battery)의 특성을 고려한 최적 정전압 충전 기법을 적용하여 축전지 과충전 현상 및 부적절한 충전에 의한 조기 수명 저하의 요인을 해결할 수 있는 방안을 모색함으로써, 태양광 발전 시스템의 활성화 및 Lift-Cycle 단가를 감소시킬 수 있는 기초 자료로 활용하고자 한다. 또한 원격 감시 시스템을 통한 시스템의 운용 상태 결과를 정확하게 실시간 수집 분석하여 대체에너지용 밀폐형 축전지 최적 충전 시스템 상용화를 위한 기초 자료로 활용하고자 한다.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2001년도 추계학술대회(한국공작기계학회)
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• pp.185-189
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• 2001

In order to prevent the production defects the optimum design of product, jig and fixture putting in the field is very significant manufacturing method. Drilling Jig is the device according to industrial demand for multi manufacturing products on the growing at alarming rate. In the field of design and making for machine tool working, welding, assembling with jig and fixture for mass production is a specific division. They require analysis of many kinds of important factors, theory and practice of machine tool operating process and jig & fixture structure, machining condition for tool making, tool materials, heat treatment of jig & fixture components, know-how and so on. In this study we designed and constructed a drilling jig of mass production and performed tryout under the Auto CAD, Auto Lisp database, that we made by database, and window environment. Especially this study is reveals with the analysis of part drawing, jig planning, jig design etc, and then the result of drill jig's making try out.

• Journal of Korean Society for Atmospheric Environment
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• 제18권E1호
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• pp.13-20
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• 2002

The electrical and chemical properties of the dielectric barrier discharge (DBD) process for the benzene removal were investigated. The benzene removal was initiated with the applied voltage higher than the discharge onset value. The removal efficiency over 95 % was obtained at approximately 1.6 kJ lite $r^{r-1}$ of the electrical energy density. The increase of the inlet concentration decreased the removal efficiency. However, the benzene decomposition rate increased with the inlet concentration . While the increase of the gas retention time enhanced the removal efficiency, the decomposition rate decreased. Identification of the optimum condition between the decomposition rate and the removal efficiency is required for field applications of the DBD process.s.

• 시스템엔지니어링학술지
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• 제12권1호
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• pp.41-58
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• 2016

Reliability Centered Maintenance (RCM) introduces a systematic method and decision logic tree for utilizing previous operating experience focused on reliability and optimization of maintenance activities. In this paper RCM methodology is applied on safety injection system for APR-1400. Functional Failure Mode Effects and Criticality Analysis (FME&CA) are applied to evaluate the failure modes and the effect on the component, system and plant. Logic Tree Analysis (LTA) is used to determine the optimum maintenance tasks. The results show that increasing the condition based maintenance will reduce component failure and improve reliability and availability of the system. Also the extension of the surveillance test interval of Safety Injection Pumps (SIPs) would lead to an improved pump's availability, eliminate the unnecessary maintenance tasks and this will optimize maintenance activities.

• Journal of the Optical Society of Korea
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• 제16권1호
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• pp.17-21
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• 2012

A surface-normal input/output volume holographic grating coupler (VHGC) operating at 1550nm wavelength region by using a $10{\mu}m$-thick DuPont photopolymer film is designed and fabricated. The angular and wavelength responses of the input/output VHGC are investigated in order to validate applicability of this device in integrated optics and optical communications. The effect of incident-beam position on the output reflectance to determine optimum condition for input coupling is also presented. The fabricated input/output VHGC exhibited an angular selectivity of ${\sim}0.027^{\circ}$, a wavelength selectivity of ~0.8 nm, and an output peak reflectance of 34.13%.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2000년도 춘계학술대회 논문집
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• pp.104-108
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• 2000

Drilling Jig is the device according to industrial demand for multi manufacturing products on the growing at alarming rate. In the field of design and making for machine tool working, welding, assembling with jig and fixture for mass production is a specific division. In order to prevent the production defects the optimum design of product, fig and fixture putting in the field is very significant manufacturing method. They require analysis of many kinds of important factors, theory and practice of machine tool operating process and its phenomena, jig & fixture structure, machining condition for tool making tool materials, heat treatment of jig & fixture components, know-how and so on. In this study we designed and constructed a drilling jig of mass production and performed tryout under the Auto CAD, database, and window environment. Especially Part1 of this study is reveals with the analysis of part drawing, jig planning, jig design etc.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제28회 추계학술대회
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• pp.292-299
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• 1998

The effect of characteristic of surface roughness on friction and sliding wear was studied experimentally with ball-on-disk type wear tester. The test was conducted with specimens those have varying arithmetic mean value, skewness and kurtosis under the condition of different load, sliding speed and lubricant viscosity. The surface of the lower skewness in negative value or the highel kurtosis tends to have low friction for the same arithmetic mean value. There is optimum arithmetic mean value surface roughness for operating variables have load, speed, etc.