• 제목/요약/키워드: Non-equilibrium

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유체가 흐르는 곡선관의 진동 해석과 비선형 평형 방정식 (Vibration Analysis and Non-linear Equilibrium Equations of a Curved Pipe Conveying Fluid)

  • 정두한;정진태
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 춘계학술대회논문집
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    • pp.983-986
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    • 2005
  • Free vibration characteristics of a curved pipe conveying fluid is studied when the pipe is clamped at both ends. Using the perturbation method, the non-linear governing equations divided into two parts; the steady state non-linear equilibrium equations and the linearized equations of motion in the neighborhood of the equilibrium position. The natural frequencies are computed from the linearized equations of motion. In this study, the equilibrium positions are determined by two types of equations, i.e., (1) the non-linear equations, and (2) the equations obtained by neglecting the non-linear terms. The natural frequencies obtained from the non-linear equilibrium equations are compared to those obtained from the linearized equilibrium equations. From the results, as the fluid velocity increases, the equilibrium position should be determined from the nonlinear equations for the vibration analysis of the curved pipe conveying fluid.

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A STUDY ON THE BEHAVIOR OF BORON DISTRIBUTION IN LOW CARBON STEEL BY PARTICLE TRACKING AUTORADIOGRAPHY

  • Mun, Dong-Jun;Shin, Eun-Joo;Koo, Yang-Mo
    • Nuclear Engineering and Technology
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    • 제43권1호
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    • pp.1-6
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    • 2011
  • The behavior of the non-equilibrium grain boundary segregation of boron in low carbon steel was studied through a particle tracking autoradiography. The behavior of the non-equilibrium grain boundary segregation of boron during continuous cooling was compared with the isothermal kinetics of the non-equilibrium grain boundary segregation of boron at the holding temperature using an effective time method. On the basis of the experiments, the cooling rate dependence of the non-equilibrium segregation of boron was explained using the time dependence of the non-equilibrium segregation of boron in low carbon steel. The experimental observations for the cooling rate dependence of the grain boundary segregation of boron are in good agreement with the time dependence of the grain boundary segregation of boron. The mechanisms of the non-equilibrium segregation of boron during cooling in low carbon steel are also discussed.

Non-Equilibrium Green Function Method in Spin Transfer Torque

  • You, Chun-Yeol
    • Journal of Magnetics
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    • 제12권2호
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    • pp.72-76
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    • 2007
  • We investigate the spin transfer torque in metallic multilayer system by employing Keldysh non-equilibrium Green function method. We study the dependences of the spin transfer torque on the detailed energy configuration of ferromagnetic, spacer, and lead layers. With Keldysh non-equilibrium Green function method applied to a single band model, we explore spin transfer torque effect in various layer structures and for various material parameters.

기능화된 실리카 비드를 이용한 수용액상의 중금속 이온의 제거공정에 대한 모사 연구 (A Simulation Study on the Removal Process of the Heavy Metal Ion in Aqueous Solution by the Functionalized Silica Beads)

  • 우윤환;주창업
    • 청정기술
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    • 제17권2호
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    • pp.150-155
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    • 2011
  • 본 연구에서는 수용액상의 금속이온을 기능화된 구형의 실리카 담체를 이용하여 제거하는 공정에 대하여 유한 차분법을 이용하여 모사하였다. 평형 모델과 비평형 모델을 수립하여 무차원 변수와 각종 변수에 대한 영향을 살펴보았으며 평형 모델과 비평형 모델의 결과를 비교하였다. 평형모델의 경우 Freundlich 등온식을 사용하였으며 비평형 모델의 경우 1차 반응속도를 가정하였다. 평형모델과 비평형 모델의 경우 변수값에 따라 비슷한 경향을 나타내었으며 금속이온 제거공정의 효율을 예측할 수 있었다. 문헌에 제시된 실험값을 활용하여 평형 모델의 예측 결과를 비교한 결과 부합되는 결과를 나타내었다.

음주량과 흡연에 따른 균형기능의 체질 상관성 연구 (A Study on The Sasang Constitutional Interrelationship of Equilibrium Function According to Drinking and Smoking)

  • 이한얼;이주용;한경수;이현;안택원
    • 사상체질의학회지
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    • 제21권3호
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    • pp.63-75
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    • 2009
  • 1. Objectives: This study was carried out to investigate the Sasang constitutional equilibrium functional difference according to drinking and smoking. 2. Methods: We analyzed the data of 300 adults(194 males, 106 females), who visited Cheonan oriental hospital of D univ. for medical examination, which includes Sasang constitution examination, equilibrium function test, questionnaire. We evaluationed the equilibrium function by measurement of open eyes and close eyes trace length, using the posturography system, according to drinking groups, smoking groups and drinking-smoking groups. 3. Results and Conclusions: The results were as follows : 1) In all subjects, trace length of heavy-drinker was significantly higher than non-drinker, trace length of smoker was significantly higher than non-smoker, trace length of drinker and smoker was significantly higher than non-drinker and non-smoker, trace length of male was significantly higher than female. 2) In Soyangin, trace length of middle-drinker was significantly higher than non-drinker. 3) In Taeumin, trace length of heavy-drinker was significantly higher than non-drinker, trace length of smoker was significantly higher than non-smoker, trace length of drinker and smoker was significantly higher than non-drinker and non-smoker. 4) In Soumin, trace length of drinker and smoker was significantly higher than non-drinker and non-smoker. The above results show that driking and smoking are one of main causes to decrease equilibrium function, specially the case of at once drinking and smoking are a potent influence. Also in Taeumin, comparing to different consitutions, the above results show that it is more obvious that drinking and smoking are influence on decrease of equilibrium function.

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초음속 습공기 유동에서 비정상 공동유동의 진동 (The Unsteady Cavity Flow Oscillation in Supersonic Moisture Air Stream)

  • 신춘식;이종성;김희동
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2008년도 제31회 추계학술대회논문집
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    • pp.341-344
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    • 2008
  • Numerical simulations have been carried out for a supersonic two-dimensional flow over open, rectangular cavities (length-to-depth ratios are L/D = 1.0) in order to investigate the effect of non-equilibrium condensation of moist air on supersonic flows around the cavity for the flow Mach number 1.83 at the cavity entrance. In the present computational investigation, a condensing flow was produced by an expansion of moist air in a Laval nozzle. The results obtained showed that in the case with non-equilibrium condensation for L/D = 1.0, amplitudes of oscillation in the cavity became smaller than those without the non-equilibrium condensation. Furthermore, the occurrence of the non-equilibrium condensation reduced the peaks of power spectrum density and the frequency of the flow field oscillation increased in comparison with the case of $S_0$ = 0.

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쌍행열게임의 평형점 (Equilibrium Points of Bimatrix Games: A State-of-the-Art)

  • 김여근
    • 한국국방경영분석학회지
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    • 제8권2호
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    • pp.57-68
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    • 1982
  • Bimatrix games are the two-person non-zero-sum non-cooperative games. These games were studied by Mills, Lemke, Howson, Millham, Winkels, and others. This paper is a systematic and synthetic survey relevant to bimatrix games. Among the many aspects of researches on bimatrix games, emphasis in this paper is placed on the relation of the equilibrium set to Nash subsets. Topics discussed are as follows: Properties of equilibrium point; The structure of equilibrium set; Relation of Nash subsets to equilibrium set; Algorithm for finding the equilibrium points; Concepts of solutions on bimatrix games.

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Ortho-to-Para Ratio Studies of Shocked $H_2$ Gas Observed from Two Supernova Remnants IC 443 and HB 21

  • 신종호;이호규;문대식
    • 천문학회보
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    • 제38권1호
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    • pp.48.2-48.2
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    • 2013
  • We present the near-infrared spectra (2.5-5.0 um) of shocked $H_2$ gas, observed with the Infrared Camera onboard the satellite AKARI. Two supernova remnants, IC 443 and HB 21, were observed. IC 443 shows a hint of non-equilibrium ortho-to-para ratio (OPR): 2.4 (-0.2, +0.3). HB 21 also shows an indication of a potential non-equilibrium OPR: 1.8-2.0. These non-equilibrium OPRs are first reported for shocked $H_2$ gas at E(v,J) > 7000 K, as far as we are aware. We concluded that the non-equilibrium OPR probably originates from dissociative J-shocks, considering several factors such as the shock combination requirement, the line ratios, and the possibility that $H_2$ gas can form on grains with a non-equilibrium OPR. The difference in the collision energy of H atoms on grain surfaces would give rise to the observed difference between the OPRs of IC 443 and HB 21, if dissociative J-shocks are responsible for the $H_2$ emission. Our study suggests that shocked-then-cooled $H_2$ gas may play as a heat reservoir with the non-equilibrium OPR.

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Transport Properties of Charged Mosaic Membrane Based on Non-equilibrium Thermodynamics

  • Song, Myung-Kwan;Yang, Wong-Kang
    • Korean Membrane Journal
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    • 제7권1호
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    • pp.67-70
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    • 2005
  • It is well known as the role of ion exchange membrane with functional group in membrane matrix. Recently, we were reported that the charged mosaic membrane within parallel array of negative and positive charge groups. In this study we are reported the properties for the various transport coefficients of metal and heavy metal ions across charged mosaic membrane based on non-equilibrium thermodynamics is not based on equilibrium state.