• Title/Summary/Keyword: Miller effect

Search Result 122, Processing Time 0.019 seconds

Frequency Response Analysis of Common-Source Amplifier Using the Exact Modeling of Miller Effect (밀러 효과의 정확한 모델링을 이용한 공통 소스 증폭기의 주파수 특성 연구)

  • Yi, Soonjai;Lee, Dong-Keon;Jeong, Hang-Geun
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.51 no.1
    • /
    • pp.172-178
    • /
    • 2014
  • This paper presents a new model of the Miller effect. The new Miller effect model is obtained from the accurate AC gain which includes the effect of the output capacitance of the common-source (CS) amplifier. The new Miller effect model consists of the series connection of a capacitance and a parallel RC circuit, one at the input and the other at the output. The frequency response obtained by the new Miller effect model is equal to that obtained from the original circuit. Even though the new model is complicated, the 3-dB frequency can be easily estimated by using the open-circuit time constants method without the node analysis.

A Case Report of Miller Fisher Syndrome (밀러피셔증후군의 불면증 환자 치험 1례)

  • Cha, Hye-Jin;Lee, Ji-Won;Seo, Young-Min;Seo, Deok-Won;Park, Se-Jin
    • Journal of Oriental Neuropsychiatry
    • /
    • v.20 no.3
    • /
    • pp.229-236
    • /
    • 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.

  • PDF

Study on the Performance Factors of Two Stage Turbo-Charging System and Maximization of the Miller Cycle (2단 과급시스템의 성능 인자 영향과 밀러 효과 극대화에 관한 연구)

  • Beak, Hyun-min;Seo, Jung-hoon;Lee, Won-ju;Lee, Ji-woong
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.25 no.7
    • /
    • pp.953-960
    • /
    • 2019
  • The Miller cycle is a diesel engine that has been developed in recent years that it can reduce NOx and improve fuel consumption by reducing the compression ratio through intake valve closing (IVC) time control. The Miller cycle can be divided into the early Miller method of closing the intake valve before the bottom dead center (BDC) and the late Miller method of closing the intake valve after the BDC. At low speeds, the late Miller method is advantageous as it can increase the volumetric efficiency; while at medium and high speeds, the early Miller method is advantageous because of the high internal temperature reduction effect due to the expansion of the intake air during the piston lowering from IVC to BDC. Therefore, in consideration of the ef ects of the early and late Miller methods, it is necessary to adopt the most suitable Miller method for the operating conditions. In this study, a two-stage turbo charge system was applied to four-stroke engines and the process of enhancing the Miller effect through a reduction of the intake and exhaust valve overlap as well as the valve change adjustment mechanism were considered. As a result, the ef ects of fuel consumption and Tmax reduction were confirmed by adopting the Miller cycle with a two-stage supercharge, a reduction of valve overlap, and an increase of suction valve lift.

A Case Report of Atypical Miller-Fisher Syndrome (비전형적 Miller-Fisher 증후군 1례)

  • Lee, Seung Min;Ji, Young Seung;Lee, Chang Woo;Jeon, Ju Hyun;Kim, Jung Ho;Kim, Young Il
    • Journal of Acupuncture Research
    • /
    • v.29 no.6
    • /
    • pp.105-110
    • /
    • 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.

Effect of Material Degradation and Austenite Grain Coarsening on the Creep life Prediction in 3.5 Ni-Cr-Mo-V Steel (3.5Ni-Cr-Mo-V 강의 크리프 수명예측에 재질열화 및 오스테나이트 결정립 조대화가 미치는 영향)

  • 홍성호;조현춘
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.18 no.11
    • /
    • pp.2837-2845
    • /
    • 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.

Evaluation on a Miller Cam for Improving the Fuel Consumption of a Large Diesel Engine (대형 디젤 엔진의 연비 향상을 위한 Miller Cam 평가)

  • Song, Changhoon;Wang, Tae Joong;Im, Heejun
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.24 no.1
    • /
    • pp.47-52
    • /
    • 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.

Improving the performance of a Medium Speed Diesel Engine Using Miller Cycle (Miller 사이클을 이용한 중형 디젤 기관 성능 개선)

  • 김동훈;김기두;하지수;김호익;김주태
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.26 no.2
    • /
    • pp.248-255
    • /
    • 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.

Anti-inflammatory and Antioxidant Effects of Zizyphus jujuba Miller var. inermis extracts (대추 추출물의 항산화 및 아토피 피부염 관련 항염증 효과)

  • Hong, Chang-Eui;Chun, Young-Hee;Lyu, Su-Yun
    • Korean Journal of Pharmacognosy
    • /
    • v.50 no.2
    • /
    • pp.86-95
    • /
    • 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.

Synchronization on the Points of Turn -off Time of Series-Connected Power Semiconductor Devices Using the Miller Effect (전력용 반도체 소자의 직렬연결시 밀러효과를 이용한 소호시점 동기화 알고리즘)

  • 심은용;서범석;이택기;현동석
    • The Transactions of the Korean Institute of Electrical Engineers
    • /
    • v.41 no.3
    • /
    • pp.237-243
    • /
    • 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.

  • PDF

Design of Voltage Controlled Oscillator using Miller Effect

  • Choi Moon-Ho;Kim Yeong-Seuk
    • Proceedings of the IEEK Conference
    • /
    • summer
    • /
    • pp.218-220
    • /
    • 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.

  • PDF