• 전자공학회논문지
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• 제51권1호
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• pp.172-178
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• 2014

본 논문은 공통 소스 증폭기의 부유 커패시턴스에 밀러 정리를 적용할 때 출력 커패시턴스를 고려한 AC 이득을 사용하여 정확한 밀러 효과 모델을 도출하였다. 정확한 AC 이득을 사용하면 부유 커패시턴스는 입력과 출력 부분에 C와 병렬 RC 회로의 직렬연결로 변환된다. 제안한 밀러 효과 모델로 구성된 등가회로의 주파수 응답 특성은 변환 전 회로의 주파수 응답 특성과 일치해 제안한 모델의 정확성이 확인되었다. 제안한 밀러 효과 모델과 소자 값이 다소 복잡하지만 공통 소스 증폭기의 특성을 이용하여 간략화 시킬 수 있다. 또한 개방 회로 시정수 방법을 사용하면 증폭기의 3-dB 주파수도 쉽게 예측이 가능하며 예측된 3-dB 주파수는 공통 소스 증폭기의 주 극점 근사 방법과 같은 값을 가진다.

• 동의신경정신과학회지
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• 제20권3호
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• pp.229-236
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• 2009

Objectives : This study is designed investigate the effect of oriental medial therapy on a 63 year old female patient had Miller Fisher Syndrome with sleeplessness. Methods : We experienced a case of Miller Fisher Syndrome and treated with herbal medicine, eletro-acupuncture. The effects of treatment were measured by sleeping hour, taken measurements with a ruler(eyeball movement). Results : Whole condition (ophthalmoplegia, ataxia and so on) was improved and Oriental treatment had a good effect on sleeping hour. Conclusions : Oriental medical treatments were very effective for the patient had Miller Fisher Syndrome with sleeplessness.

• 해양환경안전학회지
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• 제25권7호
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• pp.953-960
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• 2019

밀러 사이클은 흡입밸브 닫힘 시기 조정을 통해 압축비를 줄임으로써 NOx의 저감과 연료소비율 개선이 동시에 가능하다는 점(밀러 효과)에서 디젤엔진에 매우 활발하게 채택되어지고 있다. 밀러 사이클은 흡입 밸브를 BDC 이전에 닫는 Early 밀러 방식과 BDC 이후에 닫는 Late 밀러 방식으로 나눌 수 있다. 저속에서는 체적효율의 증가를 꾀할 수 있는 Late Miller가 유리한 반면, 중속, 고속에서는 IVC 이후 BDC 까지의 피스톤 하강 과정의 흡기의 팽창에 따른 내부 온도 감소 효과 높은 Early 밀러가 유리하다. 따라서 Early 밀러와 Late 밀러의 효과를 고려하여 운전 조건에 적합한 밀러 구현 방법을 채택할 필요가 있다. 본 연구에서는 4행정 엔진을 대상으로 2단 과급 시스템의 적용하고 흡·배기 밸브 오버랩(valve overlap)의 감소를 통해 밀러 효과를 강화하는 과정과 밸브 조정 기구를 통한 밸브 조건의 변화가 밀러 효과에 미치는 영향을 고찰하였다. 결과적으로 2단과급과 밀러사이클, 밸브 오버랩 감소와 흡입밸브 리프트 증가를 통해 연료소 비율과 최고연소온도 감소의 효과를 확인하였다.

• Journal of Acupuncture Research
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• 제29권6호
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• pp.105-110
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• 2012

Objectives : This study is designed to investigate the effect of oriental medical therapy on a 10 year old male patient had atypical Miller-Fisher syndrome with ophthalmoplegia and ptosis. Methods : We experienced a case of atypical Miller-Fisher syndrome and treated with acupuncture treatment, electro-acupuncture therapy, herbal medicine. The effect of treatment were evaluated with pictures of palpebra and eyeball movement. Results : After oriental medical treatment, ophthalmoplegia and ptosis was improved. Conclusion : Acupuncture, electro-acupuncture therapy and herbal medication is promising treatment for atypical Miller-Fisher syndrome with ophthalmoplegia and ptosis.

• 대한기계학회논문집
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• 제18권11호
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• pp.2837-2845
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• 1994

Several methods have been developed to predict on the remaining life of the old power plants. However, Larson-Miller parameter, one of existing creep life prediction methods, has not reflected the effect of material degradatioin and grain size. So this study has been carried out to research the effects of material degradation and austenite grain coarsening on the life prediction of 3.5Ni-Cr-Mo-V steel. An experimental result shows that carbide coarsening has no significant effects on the creep rupture life and the Larson-Miller parameter, but grain coarsening has an important influence on the creep ruptrure life and the Larson-Miller parameter. Therefore Larson-Miller constant, K should be determined to consider on the chemical composition and the grain size of materials.

• 한국자동차공학회논문집
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• 제24권1호
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• pp.47-52
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• 2016

Miller timing is one of the promising ways which can improve the fuel consumption of internal combustion engines. Indeed, Miller timing employing an early intake valve close is widely applied to large diesel and gas engines to enhance performance and reduce NOx emissions. In this study, performance evaluation is carried out by 1-D cycle simulation in order to estimate the effect of Miller CAM timing before BDC for a 32 L turbocharged diesel engine. To optimize Miller CAM timing, a single stage turbocharger is matched with an early intake valve close since boost pressure is a significant parameter that can control compression work in a turbocharged engine. The engine simulation result shows that there is enough potential to improve fuel consumption rate and also reduce NOx emissions at the same time.Abstract here.

• Journal of Advanced Marine Engineering and Technology
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• 제26권2호
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• pp.248-255
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• 2002

Miller cycle was studied and analyzed by engine performance simulation to achieve very low fuel consumption and to meet the IMO NOx regulation on a medium speed diesel engine. Based on the performance simulation results the intake valve closing time for HYUNDAI HiMSEN 6H21/32 engine was set at 0deg.ABDC(After Bottom Dead Center). Also, the simulation results indicated that significant NOx reduction could be achieved with low reduction of fuel consumption. The performance simulation investigated the effect of compression ratio and turbocharger on fuel consumption and NOx concentration in combination with Miller cycle. The results indicated a significant reduction of fuel consumption with keeping NOx concentration. The results of performance simulation were compared with measured data to verify simulation results. The comparison showed the maximum error was 2.34% in exhaust temperature. Also, the experimental result showed that improvement in BSFC(Brake Specific Fuel Consumption) was 5.8g/kwh with keeping NOx level similar to simulation result.

• 생약학회지
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• 제50권2호
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• pp.86-95
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• 2019

In the present study, the effect of Z. jujuba Miller var. inermis Rehder extracts on the secretion of atopic dermatitis (AD)-related cytokines and hyaluronidase activity was investigated. We prepared four fractions, butylene glycol (JB), ethanol (JE), and water (JW), with Z. jujuba Miller var. inermis extracts. JW significantly reduced the secretion of interleukin-8 and JE reduced the secretion of tumor necrosis factor-alpha in human keratinocyte HaCaT cells. Also, hyaluronidase activity was measured by enzyme assay and the fractions inhibited the activity in a dose-dependent manner. In addition, the human dermal fibroblast, HDF-n cells were treated with the extracts and antioxidant activities were measured. The results showed that the extracts increased the free radical scavenging activity and the superoxide dismutase activity. Taken together, Z. jujuba Miller var. inermis extracts reduced the secretion of AD-related cytokines and inhibited the hyaluronidase. In addition, the extracts showed antioxidant activity.

• 대한전기학회논문지
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• 제41권3호
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• pp.237-243
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• 1992

The large value of the snubber capacitor is needed to protect the devices in high voltage converters using series connected power semiconductors. But that results in more losses and longer commutation time. So, new technique of series connection is required, which can minimize the value of snubber capacitor and also promote the reliability of high voltage converters. We study on the switching characteristics of series connected power semiconductors and then propose a novel switching algorithm for series-connection which is able to implement not only the dynamic voltage balancing in spite of the differerce of switching characteristics, but the minimization of the value of snubber capacitor, through the change of the value of snubber capacitor by Miller effect. Finally, we illustrate the validity of this synchronization by computer simulation and experimental results.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.218-220
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• 2004

A new wide-band VCO topology using Miller capacitance is proposed. Contrary to conventional VCO using the Miller capacitance where the variable amplifier gain is negative, the proposed VCO uses both the negative and positive variable amplifier gain to enhance the frequency tuning range significantly. The proposed VCO is simulated using HSPICE. The simulations show that 410MHz and 220MHz frequency tuning range are obtained using the negative .and positive variable amplifier gain, respectively. The tuning range of the proposed VCO is $23\%$ of the center frequency(2.8GHz). The phase noise is -104dBc/Hz at 1MHz offset by simple model. The operating current is only 3.84mA at 2.5V power supply.