• Journal of Biosystems Engineering
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• 제26권2호
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• pp.93-104
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• 2001

A linear chemigation system, integrating agrichemical appication units of pesticide and fertilizer into an irrigation system, was selected as a suitable model for the cost savings in farm management and automation. Technical designs were conducted in the areas of structure, power, drive, control, and hydraulic systems. An experimental farm was sectioned into the fields of 40m by 200m and systemized with the linear-move chemigation system of 36m in span. The chemigation system consisted of a base unit monitoring and controlling overall operation, and a driving unit traveling linearly and injecting agrichemicals. Monitoring and interlocking systems were utilized against unexpected malfunctions of power, injection and drive systems using radio freuency modems between the units. The system can be also modified to various farm sizes and stationary systems of indoor and outdoor.

• 한국자동차공학회논문집
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• 제11권6호
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• pp.118-126
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• 2003

Digital Manufacturing is a technology facilitating effective developments and agile productions of the product via digital computer models representing physical and logical schema and the behavior of the real manufacturing systems including manufacturing resources, environments and products. For the successful application of this technology, a digital factory as a well-designed and an integrated environment is essential. In this paper, we constructed the sophisticated digital factory of a Korean automotive company's body shop, and conducted precise simulations of unit cell, lines and the whole factory for the collision check, the production flow analysis and the off-line programming. We expect that this digital factory of the body shop helps us achieve great savings in time and cost for many manufacturing preparation activities of the new car development.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1-5
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• 2005

The grinding process is replacing lapping and etching process because significant cost savings and performance improvemnets is possible. This paper presents the experimental results of wafer grinding. A three-variable two-level full factorial design was employed to reveal the main effects as well as the interaction effects of three process parameters such as wheel rotational speed, chuck table rotational speed and feed rate on TTV and STIR of wafers. The chuck table rotaional speed was a significant factor and the interaction effects was significant. The ground wafer shape was affected by surface shape of chuck table.

• 한국산학기술학회논문지
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• 제12권3호
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• pp.1408-1416
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• 2011

클라우드 컴퓨팅은 컴퓨팅 리소스의 경비 절감과 효율은 물론 서비스의 확장 및 향상을 제공한다. 그러나 클라우드 서비스 사용자(기업 등)들은 클라우드 컴퓨팅 특성에 의한 여러 가지 위험들에 대해서 많은 염려를 갖고 있다. 본 논문에서는 클라우드 컴퓨팅 환경으로 인한, 시큐리티를 포함한 여러 가지 주요 이슈들을 검토하여 보고자 한다. 또한 시큐리티에 관한 문제들을 보다 구체적으로 분석하고 클라우드 컴퓨팅에 관한 위협들을 식별하여 시큐리티 위험을 줄일 수 있는 대략적인 대응책들을 제안하였다.

• 전기학회논문지P
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• 제58권2호
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• pp.142-147
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• 2009

Conventional HP(high pressure) sodium or Metal-halide lamps have a life span of around one year requiring at least annual replacement and maintenance. High Power LED lights require no regular maintenance further increasing savings on replacement bulbs, access equipment and labour costs. New installations benefit from a substantial reduction in the cost of expensive heavy duty cable required for sodium lighting. Especially, LED light can achieve variable color temperature, high functional performance in the field of street light. There are two main method to achieve variable color temperature function of the street light. one method is using RGB multi-chip LED, the other is using Orange-White LED method. In this paper, it was compare RGB Multi-chip LED with white-orange LED for there characteristics performance.

• 산업공학
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• 제15권4호
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• pp.356-363
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• 2002

Virtual Manufacturing is a technology to facilitate effective product development and agile production by computer models representing the physical and logical schema and the behavior of real manufacturing systems including manufacturing resources, environments and products. For the successful application of this technology, a virtual factory as a well-designed and integrated environment is essential. In this research, we constructed a sophisticated virtual factory model of an automotive company's paint shop, and performed precise simulations of unit cells, lines and whole plant operations for collision check and off-line programming. It is expected that this virtual paint shop is useful for achieving time and cost savings in many manufacturing preparation and planning activities of new car development processes.

• 한국정보처리학회논문지
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• 제5권9호
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• pp.2395-2403
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• 1998

메모리 할당은 두 개의 독립적인 목표가 있다. 즉, 메모리 개수를 최소화하는 것과 한 개의 메모리 내의 레지스터(즉 단어)수를 최소화시키는 것이다. 우리의 관심은 메모리 할당시 이들 바인딩이 일어나는 순서에 있다. 바인딩이 일어나는 순서를 변경하여 세 가지의 전혀 다른 메모리 할당 알고리즘을 만들고 이들을 분석하였다. 실험 결과 경험적 비용 함수를 도입하여 부분 작업을 동시에 실행시켰을 때 메모리 면적을 최대 20%까지 줄일 수 있음을 확인하였다.

• 한국주거학회논문집
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• 제12권4호
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• pp.227-230
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• 2001

The Sri Autobindo Learning Center(SALC) is sponsoring the development of a passive solar village in Creston, Colorado, Situated near the Sangre de Cristo mountains, Savitri Village will be one of several religious communities in the area. This village will incorporate 12 permanent residences and teaching and guest facilities for fifty to one hundred people. The purpose of this study is to evaluate the passive solar elements and performance of guest house at the Sri Autobindo Learning Center(SALC). To do this evaluation, the following tasks needed to be addressed. 1. the guest house design 2. the location of weather data 3. The determination of the building heating load As part of the evaluation process, guest house design will be modified and the building load and solar saving recalculated. This process will be completed until the building performance is deemed satisfactory. The conclusion is as follows; The high solar savings fraction predicted by SUNCODE should taken as an indication that further design changes would probably not be cost effective. But adding removal overhangs or other low costs measures to increase comfort in the summer appear to be appropriate.

• 한국안전학회지
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• 제14권4호
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• pp.78-84
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• 1999

A compact air-preheating type heat exchanger was developed and tested for the ultra-high temperature heat recovery applications. For the direct use of exhaust gases up to $1200^{\circ}C$, the heat exchanger adopted a ceramic core with high strength and low thermal expansion coefficient less than $1{\times}10^{-6}^{\circ}C^{-1}$. The ceramic core was fabricated by special extrusion and bonding techniques. To minimize thermal stresses in the core, spring-loaded sealing mechanism was designed and successfully installed. 1-pass air flow scheme was adopted for the compactness and cost-savings. The pressure test for the ceramic core showed no failure under 35 kPa and less than 3% leak under 7 kPa. Flue gas simulation system was developed to investigate the performance of the heat exchanger. The test results showed normal operations of the heat exchanger up to $1200^{\circ}C$ of exhaust gases and relatively high heat recovery efficiencies of 31～39% depending upon exhaust gas temperatures..

• 한국기계가공학회지
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• 제10권3호
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• pp.87-93
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• 2011

CNC lathe machining has been widely used for parts machining of vehicles, aircraft, ships, electronics, etc. because cost savings for shortening processing time and increasing productivity are great. In this study, the purpose is to investigate the effect of cooling methods such as oil mist, water-soluble cutting oils on the workpiece surface roughness with the cutting speed, cutting depth, tool nose radius and feed rate of CNC lathe machine as a parameter in the cutting process of the aluminum alloy 2024 which is used a lot recently on aircraft parts. It is found that oil mist is coolant and water-soluble cooled by cutting the experimental conditions, cutting speed and cutting depth without effecting the surface roughness value was constant.