• 한국자동차공학회논문집
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• 제24권6호
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• pp.619-626
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• 2016

The new 1.4 L turbocharged LPG direct injection (T-LPDI) engine is presented in this paper to improve the fuel efficiency of the vehicles installed with the 2.0 L LPG port fuel injection (LPI) engine, while maintaining the performance as a downsizing concept for the new engine platform development. Firstly, the return type high pressure LPG fuel supply system is designed and mounted in the new 1.4 L T-LPDI engine. As a result, this new engine shows a much better WOT performance and approximately 8 % of improved fuel economy level, as compared to the 2.0 L LPI vehicle. Secondly, the LPDI engine specific optimized design for high pressure fuel components and fuel injection control strategies are proposed and evaluated in order to overcome the restartability problem in a heat-soaked condition called the vapor lock phenomenon. Consequently, these experimental results illustrate a great potential for the developed 1.4 L T-LPDI engine as a possible substitute for the 2.0 L LPI engine.

• Applied Biological Chemistry
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• 제19권3호
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• pp.121-129
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• 1976

우유중에 상당량 존재하는 myo-Inositol의 생성을 알아보기 위하여 3% SE-52를 충진시킨 gas-liquid chromatography에 의해 myo-Inositol의 정량을 행하고 이 myo-Inositol의 유래를 feeding 실험과 $(^{14}C)-glucose$와 (3H)-myo-Inositol을 쥐에 주사한 실험으로 알아 븐 결과 다음과 같은 결과를 얻었다. 1. 쥐우유를 G.L.C. 방법으로 분석하여 우유 100gm.당 61-91mg.의 myo-Inositol (free)을 얻었다. 2. Feeding 실험 결과 우유 myo-Inositol의 85%는 diet에서 흡수되었고 나머지는 mammary gland에서 합성된 것으로 나타났다. 3. $(^{14}C)-glucose$에서 $(^{14}C)-myo-Inositol$ 생성은 lactose의 생성과 비슷하게 한시간이내에 최고에 달하였다. 4. $(^3H)-myo-Inositol$을 lactating rat에 주사하여 실험한 결과 우유 myo-Inositol의 대부분은 혈액 myo-Inositol에서 유래되었다. $(^{14}C)-glucose$를 주사한 후 우유중에 나타난 myo-Inositol의 비방사능(比放射能)은 4시간 후에 혈액 glucose의 8%였다.

• The Korean Journal of Pain
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• 제19권1호
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• pp.77-80
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• 2006

Background: Painful experiences during procedures such as prolotherapy and intramuscular stimulation are stressful to patients and can affect the treatment outcome. We present a method for relieving pain and increasing the level of patient comfort during the procedure. Methods: Twenty six patients who requested sedation anesthesia during the procedure were examined. All patients were injected with 500 ml of 0.9% normal saline and were monitored by electrocardiography, blood pressure and pulse oximetry. The patients were supplied with oxygen (3 L/min) through a nasal cannula. Midazolam (0.02 mg/kg) and alfentanil ($8{\mu}g/kg$) was injected before the procedure and a bolus injection was administered during the procedure if patients felt any pain. The duration of the procedure, the total amount of drugs, the changes in the systolic blood pressure, heart rate, pulse oxygen saturation, sedation and pain level during procedure, satisfaction scale after the procedure, complications and the incidence of amnesia were evaluated. Results: Twenty one patients had a moderate level of sedation, 15 patients did not feel any pain during the procedure, 17 patients had high level of satisfaction (8-10). No patient experienced complications after the procedure, or unstable vital signs, and 6 patients could not remember the procedure. Conclusions: Sedation anesthesia is a safe method for relieving pain during the procedure, and most patients had a high level of satisfaction.

• 전자공학회논문지
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• 제52권11호
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• pp.36-43
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• 2015

본 연구를 통해서 초점면 배열 이차원 마이크로볼로미터를 위한 픽셀 단위의 신호취득 회로를 연구하였다. 높은 응답도와 긴 적분시간을 갖는 픽셀 단위의 구조를 위해 이 단계 바이어스 전류 억제 방식을 갖는 전류 미러 입력회로를 제안하였다. 제안하는 회로는 $0.35-{\mu}m$ 2-poly 4-metal CMOS 공정을 이용하여 설계했고, 마이크로볼로미터의 배열 크기는 $320{\times}240$이며 픽셀 크기는 $50{\mu}m{\times}50{\mu}m$이다. 제안하는 이 단계 바이어스 전류 억제 방식은 넓은 보정 범위에서 충분히 작은 보정 오차를 보이며, 설계 파라미터를 조정하여 보정 범위와 보정 오차를 간단히 최적화할 수 있다. 제안하는 회로는 높은 응답도와 1 ms 이상의 긴 적분시간을 갖기 때문에 회로의 잡음등가온도차(NETD)를 26 mK까지 개선할 수 있고, 이는 기존회로의 잡음등가 온도차인 67 mK에 비해 매우 개선된 수치이다.

• 한국연소학회지
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• 제3권1호
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• pp.59-69
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• 1998

The results of study on the active control of naturally occurring combustion oscillations with a single dominant frequency in an atmospheric dump combustor are presented. Control was achieved by an oscillatory infection of secondary fuel at the dump plane. A high speed solenoid valve with a maximum frequency of 250Hz was used as the actuator and a sound level meter, located at the combustor exit, measured the pressure fluctuations which served as the feedback signal for the control loop. Instability characteristics were mapped over a range of mean mixing section velocities from 6.7 m/s-9.3 m/s and with three mixing conditions. Different fuel/air mixing conditions were investigated by introducing varying percentages of primary fuel at two locations, one at the entrance to the mixing section and one 6 mixing tube diameters upstream of the dump plane. Control studies were conducted at a mean velocity of 9.3 m/s, with an air temperature of $415^{\circ}C$, and from flame blowout to the stoichiometric condition.

• 한국지하수토양환경학회지:지하수토양환경
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• 제27권3호
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• pp.1-10
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• 2022

Most wells developed in Jeju island before the enactment of the Groundwater Management Ordinance in 2002 are vulnerable to aquifer contamination due to inflow of upper groundwater having the high concentration of nitrate nitrogen, likely due to incomplete grouting in upper section of the wells. Although these wells require entire reinstallation, it is often necessary to rehabilitate the existing wells due to various constraints. Therefore, to identified the inflow section of contaminants, the thermal level sensor (TLS) technique was firstly applied for three wells, which enables to monitor temperature variations in every 50 cm depth. Then, the grouting material was injected to the upper section to prevent the inflow of upper contaminated groundwater into the entire aquifer. By applying TLS technique, it was found that the temperature deviations in the upper groundwater inflow section decreased sharply. Moreover, both the change in the concentration of nitrate nitrogen in the rainy/dry seasons and the average concentrations were found to decrease rapidly after grouting material injection. Consequently, the application of TLS proposed in the study turned out to be appropriate to prevent aquifer contamination.

• 터널과지하공간
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• 제31권4호
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• pp.243-269
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• 2021

2010년대 이후 고준위 방사성폐기물 심층처분, 지하 CO₂ 저장과 시추공 조사 기반 심지층 특성화를 대상으로 한 연구 및 실용화 프로젝트의 사회적 중요성이 점차 높아지고 있다. 이와 관련하여, 대심도 암반의 수리 특성에 대한 정량적이고 신뢰성있는 정보를 얻을 수 있는 현장 시험 기술의 필요성도 크게 증가하고 있다. 수년간의 연구 개발을 통해 자체 기술력으로 설계, 제작된 핵심 장치들을 기반으로 대심도 시추공 수리특성 조사 시스템(DHTS)을 독자적으로 구축하였다. 이 시스템을 사용하여 경주시 중생대 화강암과 퇴적암 지역에 위치한 심도 1 km 급 시추공 2개소에서 고정밀도 정압 주입시험을 성공적으로 수행하였다. 현장 시험에서 미세 유량 주입/조절 모듈을 사용하여 0.01 l/min 미만의 매우 낮은 유량 측정이 가능하였다. 본 논문에서는 DHTS의 주요 특성을 소개하고 대심도 저투수성 암반 환경 하에서 수행된 고정밀도 시험 결과에 대해 간단히 논의하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.432-437
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• 2001

It is necessary to improve mechanical and optical porperties in the optical disk substrates as the information storage devices with high storage density using blue laser are being developed. Injection compression molding is regarded as the most suitable process to manufacture optical disk substrates for quality recording and read-out. In the present research, the effects of processing conditions and the insulation layer thickness on gapwise birefringence and the land-groove pattern were investigated. It was found that the values of the birefringence distribution were very sensitive to mold temperature history, and the level of birefringence reduced and, furthermore, the quality of replication was improved due to the insulation layer.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1996년도 춘계학술발표회논문집(2)
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• pp.368-373
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• 1996

A simple set of the transition criterion of the condensation regimes and the heat transfer coefficients on the direct contact condensation of the core makeup tank is developed, and implemented in RELAP5/MOD3.1 The condensation regimes are divided into two regimes: supply limit and condensation limit. In mode]ing the transition criterion between two regimes, a large-eddy model developed by Theofanous is used, and the empirical coefficient of the present large-eddy model is close to that of the large-eddy model. It turns out that the modified code better predicts the experimental data, especially the injection flow rate and the water level trend than the original code does.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.64-66
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• 2009

We obtained high performance of n-type organic thin film transistors (OTFTs) using a solution process. N, N' bis-(octyl-)-dicyanoperylene-3,4:9,10-bis(dicarboximide) (PDI-$8CN_2$) in ambient air. Low work function interlayer on source/drain is needed to enhance the electron injection to low LUMO level of n-type organic semiconductor. By using self-assembled monolayer (SAM) the field-effect mobility of 0.33 $cm^2$/Vs was achieved.