• 제목/요약/키워드: kinetic

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Management of Discon tinuous Reconstruction In the Evolution Stage of Kinetic Scheme

  • Ohwada Taku;Kobayashi Seijiro
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2003년도 The Fifth Asian Computational Fluid Dynamics Conference
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    • pp.189-190
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    • 2003
  • A New kinetic scheme for the compressible Navier-Stokes equations is developed. While the conventional approach, such as KFVS scheme, employs the splitting algorithm and computes the numerical flux on the basis of the collisionless equation, the present approach employs the splitting algorithm in the evaluation of the numerical flux, where the collision effect is explicitly taken into account. However, the initial condition employed in the computation is slightly different from the conventional Chapman-Enskog NS distribution function. The present study also reveals the background of the existing kinetic schemes. such as the KFVS scheme and Gas-Kinetic BGK scheme.

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기-액 기둥에서 기포유동에 관한 연구 (A Study on the Bubble Flow in the Gas-Liquid Plume)

  • 서동표;홍명석;오율권
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.2105-2108
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    • 2003
  • The characteristics of upward bubble flow were experimentally investigated in a liquid bath. In the present study, a thermal-infrared camera and high speed CCO camera were used to measure their temperature and local rising velocity, respectively. Heat transfer from bubble surface to water is largely completed within z=10mm from the nozzle, and then the temperature of bubble surface reaches that of water rapidly. The rising velocity of bubble was calculated for two different experimental conditions: 1) bubble flow without kinetic energy 2) with kinetic energy. Bubble flow without kinetic energy starts to undergo the effect of inertia force 10cm away from the nozzle. Whereas, kinetic energy is dominant before 30 cm away from the nozzle in bubble flow, but after this point, kinetic energy and inertial force are applied on bubble flow at the same time.

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PIV 계측에 의한 $180^{\circ}$곡관 출구에 연결된 직관에서 층류정상유동의 운동에너지 (Kinetic energy of Laminar Steady flows in the Exit Reguon Connected to the straight Square-sectionnal $180^{\circ}$ curved Duct by using PIV)

  • 이종구;이홍구;손현철;이행남;박길문
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2002년도 학술대회지
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    • pp.521-524
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    • 2002
  • In the present study, kinetic energy of laminar steady flow in the exit region connected to the square-sectional $180^{\circ}$curved duct was investigated experimentally. The experimental study for air flows was conducted to measure kinetic energy distributions by using the Particle Image Velocimetry(PIV) system with the data acquisition and processing system of Cactus 2000 software. The results obtained from experimental studies are summarized as follows : (1) The critical Reynolds number for a change from laminar steady flow to transitional steadt flow was about 1910, in the 50 region of dimensionless axial position (x/Dh) whirh was considered as a fully developed flow region. (2) Maximum kinetic energy of laminar steady flow was gradually increased as the Reynolds number increased.

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대학생의 자아분화와 동적 가족화 반응 특성 연구 (Study on the self-differentiation of the university students and Kinetic Femily Drawing Respondent Characteristics)

  • 이정숙;김윤희
    • 한국생활과학회지
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    • 제9권4호
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    • pp.429-445
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    • 2000
  • This study was analyzed for the relationship between the self-differentiation of the university students and Kinetic Family Drawings that was responded their mental aspect. Results of this study were following. First, the level of self-differentiation by sex, age, region and grade was significantly different. Second, Kinetic Family Drawings respondent characteristics by their sex, age, region, grade and sibling order was significantly different. Third, in the relationship between the self-differentiation of the university students and Kinetic Family Braving respondent characteristics, when the group had less conflict and more interaction among family members, they could separate their subjective and objective tension and they could attach to their parents. In the case that crisis was occurred in their family, they had less possibility to represent dysfunctional communication style or regressive behaviors.

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A Chemical Kinetic Model Including 54 Reactions for Modeling Air Nonequilibrium Inductively Coupled Plasmas

  • Yu, Minghao;Wang, Wei;Yao, Jiafeng;Zheng, Borui
    • Journal of the Korean Physical Society
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    • 제73권10호
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    • pp.1519-1528
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    • 2018
  • The objective of the present study is the development of a comprehensive air chemical kinetic model that includes 11 species and 54 chemical reactions for the numerical investigation of air nonequilibrium inductively coupled plasmas. The two-dimensional, compressible Navier-Stokes equations coupled with the electromagnetic-field equations were employed to describe the fundamental characteristics of an inductive plasma. Dunn-Kangs 32 chemical-reaction model of air was reconstructed and used as a comparative model. The effects of the different chemical kinetic models on the flow field were analyzed and discussed at identical/different working pressures. The results theoretically indicate that no matter the working pressure is low or high, the use of the 54 chemical kinetic model presented in this study is a better choice for the numerical simulation of a nonequilibrium air ICP.

Synthesis of Carbobenzoxy-alanyl-thiaarginine (thialysine) benzyl ester and kinetic Studies with Trypsin

  • 홍남주;장성훈;진동훈
    • Bulletin of the Korean Chemical Society
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    • 제19권6호
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    • pp.689-695
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    • 1998
  • Carbobenzoxy-alanyl-thiaarginine benzyl ester and carbobenzoxy-alanyl-thialysine benzyl ester were synthesized in solution. Kinetic studies were carried out using three different analytical methods, semi-classical method, progress curve analysis and competitive spectrophotometry. In competitive spectrophotometry, carbobenzoxy-valyl-glycyl-arginyl-p-nitroaniline was used as a detector. Kinetic constants such as $K_m$ and $V_{max}$ measured by competitive spectrophotometry are almost the same as those values measured by semi-classical method. Colorimetric Ellman's assays showed the thio-peptido mimetics to be a suitable substrates for trypsin. Kinetic studies with trypsin gave $K_m$ of 2.33 mM and $k_{cat}$ of $1.50{\times}10^5\;min^{-1}$ for carboxy-alanyl-thiaarginine benzyl ester and $K_m$ of $3.41{\times}10^{-3}\; Mm\; and\; k_{cat}\; of\; 520{\times}102\; min^{-1}$ for carbobenzoxy-alanyl-thialysine benzyl ester, respectively. Kinetic constants $(K_m=2.04{\times}10^{-2}\; mM, K_{cat}=4.42{\times}10^3 \;min^{-1})$ for natural substrate, carbobenzoxy-alanyl-lysine benzyl ester, were also evaluated by competitive spectrophotometry in order to compare the mode of binding on trypsin.

A Kinetic Study of Biphenyl Type Epoxy-Xylok Resin System with Different Kinds of Catalysts

  • 한승;김환근;윤호규;문탁진
    • Bulletin of the Korean Chemical Society
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    • 제18권11호
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    • pp.1199-1203
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    • 1997
  • The investigation of cure kinetics of biphenyl epoxy (4,4-diglycidyloxy-3,3,5,5-tetramethyl biphenyl)-xylok resin system with four different catalysts was performed by differential scanning calorimeter using an isothermal approach. All kinetic parameters of the curing reaction including the reaction order, activation energy and rate constant were calculated and reported. The results indicate that the curing reaction of the formulations using triphenylphosphine (TPP) and 1-benzyl-2-methylimidazole (1B2MI) as a catalyst proceeds through a first order kinetic mechanism, whereas that of the formulations using diazabicyloundecene (DBU) and tetraphenyl phosphonium tetraphenyl borate (TPP-TPB) proceeds by an autocatalytic kinetic mechanism. To describe the cure reaction in the latter stage, we have used the semiempirical relationship proposed by Chern and Poehlein. By combining an nth order kinetic model or an autocatalytic model with a diffusion factor, it is possible to predict the cure kinetics of each catalytic system over the whole range of conversion.

A TYPE OF FRACTIONAL KINETIC EQUATIONS ASSOCIATED WITH THE (p, q)-EXTENDED 𝜏-HYPERGEOMETRIC AND CONFLUENT HYPERGEOMETRIC FUNCTIONS

  • Khan, Owais;Khan, Nabiullah;Choi, Junesang;Nisar, Kottakkaran Sooppy
    • Nonlinear Functional Analysis and Applications
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    • 제26권2호
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    • pp.381-392
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    • 2021
  • During the last several decades, a great variety of fractional kinetic equations involving diverse special functions have been broadly and usefully employed in describing and solving several important problems of physics and astrophysics. In this paper, we aim to find solutions of a type of fractional kinetic equations associated with the (p, q)-extended 𝜏 -hypergeometric function and the (p, q)-extended 𝜏 -confluent hypergeometric function, by mainly using the Laplace transform. It is noted that the main employed techniques for this chosen type of fractional kinetic equations are Laplace transform, Sumudu transform, Laplace and Sumudu transforms, Laplace and Fourier transforms, P𝛘-transform, and an alternative method.

The Theoretical Calculations of Kinetic and Thermodynamics Parameters and Anharmonic Correction for the Related Reactions of NO3

  • Yu, Hongjing;Liu, Yancheng;Xia, Wenwen;Wang, Li;Jiang, Meiyi;Hu, Wenye;Yao, Li
    • 대한화학회지
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    • 제65권6호
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    • pp.419-432
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    • 2021
  • According to the transition state (TS) theory, Gaussian software and Yao and Lin (YL) method, the thermodynamics and kinetic data respectively were calculated, and anharmonic effect was considered for related reactions of NO3. The methods of calculating and fitting kinetic and thermodynamics parameters were provided by least square method and related equations in this paper. Notably, the fitted E of Arrhenius equation was close to the calculated barrier of related reaction by QCISD(T) method. Therefore, the kinetic fitting result can well express the physical meaning of E in Arrhenius equation. Besides, the conversion process and the reaction mechanism of NO3 were researched. For NO3, it seemed that its instability results from its easy reaction with other substances rather than the decompose reaction of itself.

The Effects of Closed Kinetic and Open Kinetic Chain Exercises Using Knee Reposition Sense in Chronic Stroke Patients

  • Lee, Kyu-Young;Shin, Won-Seob
    • The Journal of Korean Physical Therapy
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    • 제26권3호
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    • pp.182-190
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    • 2014
  • Purpose: This study aimed to determine the effects of open kinetic chain exercise (OKCE) and closed kinetic chain exercise (CKCE) using knee reposition sensing on balance, strength, and knee joint reposition sense (JPS) in chronic stroke patients. Methods: Twenty-nine hemiplegic patients participated in this study. Participants were randomly divided into 3 groups, CKCE, OKCE, and controls, with 9, 10, and 10 participants, respectively. The CKCE group completed CKCE using knee reposition sensing, whereas the OKCE group completed OKCE using knee reposition sensing. The control group completed conventional physical therapy. Results: Significant differences between the CKCE and OKCE groups were apparent for all outcomes except the functional reaching test. The CKCE group displayed significant improvements in knee JPS versus the OKCE and control groups (p<0.01). The OKCE group displayed significant improvements in knee extensor muscle strength versus the CKCE and control groups (p<0.05). The CKCE and OKCE groups displayed significantly improvements in static balance versus the control group (p<0.05). Conclusion: CKCE and OKCE improved balance, strength, and knee JPS. Additionally, CKCE might provide a more useful intervention benefit than OKCE for increasing knee JPS, a weight-bearing task. OKCE was sufficient to improve the knee extensor muscle strength.