• 제목/요약/키워드: Studying effect

검색결과 914건 처리시간 0.029초

히트펌프 냉·난방 시스템의 온도 자동제어에 관한 연구 (A Study for Automatic Temperature Control of the Heating-Cooling System with Heat Pump)

  • 구창대
    • 한국산업융합학회 논문집
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    • 제14권4호
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    • pp.143-149
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    • 2011
  • The experiment has been investigated the room temperature change under adjusting 4-way valve which was installed for cooling and heating switch. Beside, the temperature of heat pump was controlled automatically for autonomously adjusting temperature and maintaining a constant room temperature. As results, Inlet & outlet temperature differences of compressor are $95^{\circ}C$ in cooling condition and $57^{\circ}C$ in heating condition. Therefore, Compression efficiency of cooling effect is higher than heating effect. In addition, Heat exchange effect of Cooling system condition is higher than heating system. This results can be used for studying about automatic temperature control of cooling and heating system with heat pump and 4way valve.

증기 공동현상이 발생하는 무한 소폭 스퀴즈 필름 댐퍼 성능과 오일 공급압력의 영향 (The Effect of Oil Supply Pressure on the Performance of Vapor Cavitated Short Squeeze Film Dampers)

  • 정시영
    • Tribology and Lubricants
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    • 제24권3호
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    • pp.147-153
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    • 2008
  • The effect of oil supply pressure on the performance of vapor cavitated short squeeze film dampers is examined. Vapor cavitation is characterized by film rupture occurring as a result of evaporating oils. The pressure of vapor cavity in the film is almost zero in absolute pressure and nearly constant. Pan's model about the shape of vapor cavity is utilized for studying the effect of vapor cavitation on the damping capability of a short squeeze film damper. As the level of oil supply pressure is increasing, vapor cavitation is suppressed so that the direct damping coefficient increases and the cross coupled damping coefficient decreases. Futhermore, the analysis of the unbalance responses of a rigid rotor supported on cavitated squeeze film dampers shows that a significant reduction in rotor amplitude and force transmissibility is possible by controlling the oil supply pressure into short squeeze film dampers.

전력설비의 고조파진단에 관한 연구 (A Study on Harmonics Detection for Power Equipments)

  • 이범;김용하;최상규;김종국
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2000년도 추계종합학술대회
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    • pp.669-672
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    • 2000
  • This paper presents the methodology which analyze the effect of harmonics in power system. Considering the effect of less-harmonics, economic life and system loss, we have made the comprehensive countermeasure. According to the results of studying harmonics diagnosis and countermeasure, the following problems are pinpointed: protection of power system double investment space of the field. Therefore, in the initial stage, the countermeasure of harmonics trouble are set up. h a results, the following work has been done: $\circled1$ Generation source of harmonics and it's effect into en power system $\circled2$ Review of law related to harmonics, $\circled3$ Countermeasures to reduce the harmonics

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Nonlinear vibration of Timoshenko beam due to moving loads including the effects of weight and longitudinal inertia of beam

  • Wang, Rong-Tyai
    • Structural Engineering and Mechanics
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    • 제10권3호
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    • pp.197-209
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    • 2000
  • The effects of weight and axial inertia of a beam are taken into account for studying the nonlinear vibration of the Timoshenko beam due to external loads. The combination of Galerkins method and Runge-Kutta method are employed to obtain the dynamic responses of the beam. A concentrated force and a two-axle vehicle traversing on the beam are taken as two examples to investigate the response characteristics of the beam. Results show that the effect of axial inertia of the beam increases the fundamental period of the beam. Further, both the dynamic deflection and the dynamic moment of the beam obtained with including the effect of axial inertia of the beam are greater than those of the beam without including that effect of the beam.

A New Scaling Theory for the Effective Conducting Path Effect of Dual Material Surrounding Gate Nanoscale MOSFETs

  • Balamurugan, N.B.;Sankaranarayanan, K.;Suguna, M.
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제8권1호
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    • pp.92-97
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    • 2008
  • In this Paper, we present a scaling theory for dual material surrounding gate (DMSGTs) MOSFETs, which gives a guidance for the device design and maintaining a precise subthreshold factor for given device parameters. By studying the subthreshold conducting phenomenon of DMSGTs, the effective conductive path effect (ECPE) is employed to acquire the natural length to guide the design. With ECPE, the minimum channel potential is used to monitor the subthreshold behavior. The effect of ECPE on scaling factor significantly improves the subthreshold swing compared to conventional scaling rule. This proposed model offers the basic designing guidance for dual material surrounding gate MOSFETs.

가돌리늄의 자기열량효과에 대한 실증실험 (Demonstrative Experiments on the Magnetocaloric Effect of Gadolinium)

  • 이종석
    • 설비공학논문집
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    • 제16권4호
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    • pp.383-389
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    • 2004
  • Magnetic refrigeration is based on the magnetocaloric effect (MCE) - the ability of some materials to heat up when magnetized and cool down when removed from the magnetic field. The available techniques for studying the MCE we: (1) direct measurements by monitoring the change in the material's temperature during the application or removal of the magnetic field; and (2) indirect calculations from the experimental data of magnetization and/or specific heat as a function of the temperature and magnetic field. The MCE of gadolinium (Gd) has been demonstrated by direct measurements of temperature change, and isothermal magnetic entropy changes and adiabatic temperature changes have been calculated.

압출용 스크류 모델에서의 혼돈적 교반 (A numerical study on a chaotic stirring in a model for a single screw extruder)

  • 서용권;김용균;문종춘
    • 대한기계학회논문집B
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    • 제21권12호
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    • pp.1615-1623
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    • 1997
  • Numerical study on the chaotic stirring of the screw extruder model proposed has been performed. The velocity field was used in obtaining the trajectories of passive particles for studying the stirring effect of the screw extruder. Two nonlinear dynamical tools, that are Poincare sections and Lyapunov exponents, were used in analysing the stirring effect. The Poincare sections and the Lyapunov exponents show that the stirring effect is most satisfactory, when n(the number of flights in a section) is 1, for the case a (aspect ratio ; flight height divided by the spacing between flights) being O.1. It is also required to set n=3, or 5 at a= 0.2, 0.3 for a uniform stirring.

The effect of pre- and after-treatment of sevoflurane on central ischemia tolerance and the underlying mechanisms

  • Xu, Hao;Mei, Xiao-Peng;Xu, Li-Xian
    • Journal of Dental Anesthesia and Pain Medicine
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    • 제18권1호
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    • pp.1-8
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    • 2018
  • In recent years, with continuous research efforts targeted at studying the effects of pre- and after-treatment of inhaled anesthetics, significant progress has been made regarding the common clinical use of low concentrations of inhaled sevoflurane and its effect on induced central ischemia tolerance by pre- and post-treatment. In this study, we collected, analyzed, classified, and summarized recent literature regarding the effect of sevoflurane on central ischemia tolerance and its related mechanisms. In addition, we provide a theoretical basis for the clinical application of sevoflurane to protect the central nervous system and other important organs against ischemic injury.

차세대 고속전철에 적용할 IT 및 스마트센서 기술의 타당성 검토에 관한 연구 (Engineering Feasibility of IT and Smart Sensor Technology Applications for the Next Generation High Speed Train)

  • 장덕진;강송회;송달호
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2009년도 춘계학술대회 논문집 특별세미나,특별/일반세션
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    • pp.547-556
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    • 2009
  • In this paper, we tried to find the engineering feasibility of the component functions of the seven selected application technologies which are going to be installed on the next generation high speed train as the IT and smart sensor application technologies. The component functions of the seven applications, including the "Emergency or reminder notification", were identified and analyzed. In order to justify the feasibility of applications development, effect analysis and sufficiency analysis were performed. In effect analysis, how each function has an effect on safety, convenience, and efficiency of the passengers and attendants was evaluated. In sufficiency analysis, the importance and implementability of each function as a component was evaluated. The feasibility analysis was focused on the technical aspects of the functions. The following work will be the settlement of the final applications that are going to be designed and implemented. This will be done by studying the strategic feasibility in relation to the service or business of the high speed train.

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Theoretical Researches of Kinetics and Anharmonic Effect for the Reactions Related to NO in the Ozone Denitration Process

  • Yu, Hongjing;Xia, Wenwen;Liu, Yancheng;Yao, Li
    • 대한화학회지
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    • 제65권3호
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    • pp.185-196
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    • 2021
  • For studying the reaction mechanism of the reactions related to NO in the ozone denitration reactions, the harmonic and anharmonic rate constants were calculated by the transition state (TS) theory and Yao and Lin (YL) method. According to above calculations, the reactions of NO with O3 and NO3 play an essential role, and the kinetic parameters considering anharmonic effect were fitted. Furthermore, the rate constants were up as temperature increasing, and the tendencies of high temperature were more gradual than the low temperature. The research will provide theoretical basis for the ozone denitration reactions.