• 대한설비공학회지:설비저널
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• 제22권1호
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• pp.1-16
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• 1993

• 동력기계공학회지
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• 제17권6호
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• pp.5-10
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• 2013

Diesel engines have the advantages of good fuel efficiency and low emissions. Therefore, car makers have been developed various kinds of diesel engine management system to clean up emissions while improving fuel efficiency. One of them is the common rail system. In the common rail system, diesel fuel is injected into the combustion chamber at ultra high pressures up to 1,800 bar to ensure more complete combustion for cleaner exhaust gas, and highly precise multiple injection reduces NOx emission, combustion noise and vibration. Generally speaking, common rail system consists of booster pump, high pressure pump, common rail, injectors, control valves, and sensors. The high pressure pump receives low pressure fuel from the booster pump and supply high pressure fuel to injectors through the high pressure common injection rail. Therefore, high pressure pump has an important role in common rail system. In this paper, we have investigated the performance of high pressure pump of common rail system.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.962-967
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• 2011

발사체의 추력을 증진시키기 위해서 사용되는 고체 부스터나 궤도 투입을 위한 킥 모터 플룸의 주요 성분인 알루미나 입자의 복사물성을 도출하기 위해서 입자의 복사특성을 분석하였다. 특히 입자의 흡수나 산란현상이 파장의 함수이므로, 이를 전 파장에 대한 총방사율로 표현할 수 있도록 수식을 정리하였고, 입자의 크기 및 Complex Index of Refraction을 Mie 이론에 도입하여 최종적으로 총 방사율을 도출하였다. 결과적으로 방사율은 온도에 따라 증가하는 것을 확인할 수 있었다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1999년도 전력전자학술대회 논문집
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• pp.323-326
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• 1999

For decrease the harmonic current components of the power source, a first method is insert the choke coil that used the choke input type rectifier, the booster chopper circuit and buck chopper circuit. And the several method are studying like as the PWM(Pulse Width Modulation) converter and the active filter type which is used the high frequency switching and the sinusoidal wave formed input current. In this type, there are many problem as a low efficiency, increased the noise, the high leakage current and cost up by the high frequency switching. For improve this problems, the partial resonan method is used on the booster inducter and lossles snubber condenser. This method decreased the distortion factor has lower harmonic components than the hard switching and there is no switching loss by the ZCS(Zero Current Switching) at switch turn-on and the ZVS(Zero Voltage Swithcing) at switch turn-off

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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• pp.191-196
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• 2001

In the systems with largely pipe head loss, variable speed pumps are generally used because substantial energy saving can be expected from such systems by controlling pump speed and also they offer simpler maintenance and operational ease even in conditions where abrupt changes In flow rate and head can occur. The invertor or the fluid coupling system are mainly adopted to control the rotating speed. In this paper, operating conditions at Migum pressing pump station(5 stage), where the fluid coupling system was the first installed for KOWACO, are investigated and analysed so that information thus gained can be usefully employed in the efficient operation of variable speed pump in new installations of in-line booster pumping station.

• 화약ㆍ발파
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• 제21권1호
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• pp.19-27
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• 2003

국내 석회석 광산에서는 벤치 발파패턴을 현장의 KNOW-HOW에 따라 가장 경제저인 발파패턴을 적용하고 있다. 그러나 인건비 재료비등 제반경비가 상승함에 따라 좀 더 효율적인 발파방법의 개선이 요구되고 있는 바, 현 석회석 광산에서의 발파패턴을 보다 개선하여 경제적인 발파패턴을 적용하고, 그에 따른 고려해야 할 사항들을 본 논문에서 연구 하고자 한다. 따라서 국내 석회석 광산의 발파 패턴과 외국의 광산발파 패턴을 비교하고, 수치해석을 적용하여 기존의 발파 패턴에서 장약길이, 공간격, 장약량의 변화, 천공경은 102mm에서 115mm로 변화하고 장양방법을 단일장약에서 이중장약으로 변화하여 동해 쌍용자원에서 시험을 실시하였다. 연구 결과 장약길이의 20% 감소는 Power Factor를 (20%)낮게 하나, 파쇄효과는 28% 감소하고 Back Break가 (7%)이상 발생하였으며, 천공경을 115mm로 적용하고, 장약길이를 11% 감소를 위하여 이중장약을 적용하여 Power Factor를 10% 낮게 하였을 때 파쇄효과는 22.45%가 증대되었으며, 기존 동일 패턴에 Booster를 추가로 적용하였을 때 파쇄효과는 13.21% 가 증대되었고, Power Factor는 11% 가 감소되는 것을 알 수 있었다.

• 식물조직배양학회지
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• 제24권4호
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• pp.225-231
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• 1997

For genetic engineering to be commercially viable, an efficient transformation system is needed to produce transgenic plane from diverse genotypes ("generalized protocol"). Development of such a system requires optimization of a number of components such as gene transfer agent, plant tissues competent for both regeneration and transformation, and control of transgene expression. Although several novel gene transfer methods have been developed for plane, a majority of stably transformed plane express the introduced genes at low levels. Moreover, silencing of selectable marker genes shortly after their incorporation into plant chromosomes may result in low recovery of transgenic tissues from selection. Matrix attachment regions (MARs) are DNA sequences that bind to the cell's proteinaceous nuclear matrix to form DNA loop domains. MARs have been shown to increase transgene expression in tobacco cells, and reduce position in mature transgenic plants. Flanking an antibiotic resistance transgene with MARs should therefore lead to improved rates of transformation in a diversity of species, and may permit recalcitrant species and genotypes to be successfully transformed. Literature review and recent data from my laboratory suggest that MARs can serve as a transformation booster in recalcitrant plant species.

• 한국자동차공학회논문집
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• 제9권2호
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• pp.137-142
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• 2001

A throttle/brake control law for the intelligent cruise control(ICC) systems has been proposed in this paper. The ICC system consists of a vehicle detection sensor, the control algorithm and a throttle/brake actuators. The control performance has been investigated through vehicle tests. The test vehicle is equipped with a MMW radar sensor, a solenoid-valve-controlled Electronic-Vacuum-Booster(EVB) and a step-motor controlled throttle actuator. The results indicate the proposed throttle/brake control laws can provide satisfactory vehicle-to-vehicle distance and velocity control performance.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.741-746
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• 2001

This paper presents an investigation of a vehicle-to-vehicle distance control using a Hardware-in-the-Loop Simulation(HiLS) system. Since vehicle tests are costly and time consuming, how to establish a efficient and low cost development tool is an important issue. The HiLS system consists of a stepper motor, an electronic vacuum booster, a controller unit and two computers which are used to form real time simulation and to save vehicle parameters and signals of actuator through a CAN(Controller Area Network). Adoption of a CAN for communication is a trend in the automotive industry. Since this environment is the same as that of a real vehicle, a distance control logic verified in laboratory can be easily transfered to a test vehicle.

• 한국항공우주학회지
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• 제32권1호
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• pp.58-64
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• 2004