• Title/Summary/Keyword: Master equation

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A Study on the Development of Regional Master Recession Curve Model

  • Lee, Jae-Hyoung;Oh, Nam-Sun;Lee, Hee-Ju
    • Journal of Soil and Groundwater Environment
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    • v.6 no.3
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    • pp.61-71
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    • 2001
  • A regional master recession curve model to predict groundwater discharges in a given basin was presented. Considering a stream-aquifer system, both theoretical and experimental baseflow equations were compared and a practical groundwater discharge equation was derived, The groundwater discharge equation was expanded and transformed to the discharge equation at the basin exit. For practical use, the equation was expressed as a function of watershed area, the mean slope of basin and the recession constant. To verify the model, the model was applied to Ssang-chi basin where long-term and temporal hydrological data at the upper basin were collected. Our results show that a master recession curve of unmeasured area can be predicted.

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Dynamics of Resonant Energy Transfer in OH Vibrations of Liquid Water

  • Yang, Mi-No
    • Bulletin of the Korean Chemical Society
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    • v.33 no.3
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    • pp.885-892
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    • 2012
  • Energy transfer dynamics of excited vibrational energy of OH stretching bonds in liquid water is theoretically studied. With time-dependent vibrational Hamiltonian obtained from a mixed quantum/classical calculation, we construct a master equation describing the energy transfer dynamics. Survival probability predicted by the master equation is compared with numerically exact one and we found that incoherent picture of energy transfer is reasonably valid for long-time population dynamics. Within the incoherent picture, we assess the validity of independent pair approximation (IPA) often introduced in the theoretical models utilized in the analysis of experimental data. Our results support that the IPA is almost perfectly valid as applied for the vibrational energy transfer in liquid water. However, proper incorporation of radial and orientational correlations between two OH bonds is found to be critical for a theory to be quantitatively valid. Consequently, it is suggested that the Forster model should be generalized by including the effects of the pair correlations in order to be applied for vibrational energy transfer in liquid water.

The empirical corner stiffness for right-angle frames of rectangular and H-type cross-sections

  • Kwon, Young-Doo;Kwon, Soon-Bum;Gil, Hyuck-Moon;Cho, Hui-Jeong
    • Structural Engineering and Mechanics
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    • v.51 no.3
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    • pp.471-485
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    • 2014
  • Until now, the finite corner stiffness of the right-angle frames used as horizontal girders in a bonnet, have not been considered during the design process to result in not a precise result. This paper presents a design equation set for right-angle frames used as horizontal girders in a bonnet assuming rigid corner stiffness. By comparing the center stresses of the right-angle frame according to the design equation set with the results of the finite element method, the master curves for the empirical corner stiffness can be determined as a function of slenderness ratio. A second design equation set for a right-angle frame assuming finite corner stiffness was derived and compared with the first equation set. The master curves for the corner stiffness and the second design equation set can be used to determine the design moments at the centers of the girder so that the bending stresses can be analyzed more precisely.

Prediction of the Rhelolgical of Soybean Curd during Storage by using WLF equation (저장중의 두부에 WLF식을 이용한 물성 변화 예측에 관하여)

  • Jang, Won-Young;Kim, Byung-Yong;Kim, Myoung-Hwan
    • Korean Journal of Food Science and Technology
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    • v.27 no.2
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    • pp.193-198
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    • 1995
  • The changes in the rheological properties of soybean curd upon the various storage temperatures ($5{\sim}25^{\circ}C$) were measured by the stress-relaxation test and analysed by time-temperature superposition theory. As the storage temperature was lower, higher initial and equilibrium stress of soybean curd were observed. When the stress-relaxation curves were moved horizontally by using the shift-factor on the basis of reference temperature, the master curve was obtained. By applying master curve and shift-factor to the WLF (Williams-Landel-Ferry) equation, activation energy (30kcal/mol) was calculated and storage time at the specific temperature could be predicted, suggesting the equivalent shelf-life of soybean curd texture.

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Vibration Analyses and Design of Resonance Avoidance of the Unmanned Helicopter Master (무인 헬리콥터 마스터의 진동해석 및 공진회피 설계)

  • Lee, Seong-Chul;Son, In-Soo;Hur, Kwan-Do
    • Journal of the Korean Society for Precision Engineering
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    • v.28 no.8
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    • pp.951-958
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    • 2011
  • In this paper, the purpose is to investigate the vibration characteristics and the design of resonance avoidance of the unmanned helicopter master. Based on the Euler-Bernoulli beam theory for helicopter master, the equation of motion is derived by using extended Hamilton's principle. It was studied about the natural frequency of helicopter master as the design variances(tip mass, length and diameter of master). Also, it was compared the theoretical results for natural frequency with the results of FE analysis. The results of this study showed the vibration characteristics of helicopter master for the design of resonance avoidance.

A Theoretical Representation of Relaxation Processes in Complex Spin System Using Liouville Space Method

  • Kyunglae Park
    • Bulletin of the Korean Chemical Society
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    • v.14 no.1
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    • pp.21-29
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    • 1993
  • For the study of relaxation processes in complex spin system, a general master equation, which can be used to simulate a vast range of pulse experiments, has been formulated using the Liouville representation of quantum mechanics. The state of a nonequilibrium spin system in magnetic field is described by a density vector in Liouville space and the time evolution of the system is followed by the application of a linear master operator to the density vector in this Liouville space. In this master equation the nuclear spin relaxation due to intramolecular dipolar interaction or randomly fluctuating field interaction is explicitly implemented as a relaxation supermatrix for a strong coupled two-spin (1/2) system. The whole dynamic information inherent in the spin system is thus contained in the density vector and the master operator. The radiofrequency pulses are applied in the same space by corresponding unitary rotational supertransformations of the density vector. If the resulting FID is analytically Fourier transformed, it is possible to represent the final nonstationary spectrum using a frequency dependent spectral vector and intensity determining shape vector. The overall algorithm including relaxation interactions is then translated into an ANSIFORTRAN computer program, which can simulate a variety of two dimensional spectra. Furthermore a new strategy is tested by simulation of multiple quantum signals to differentiate the two relaxation interaction types.

Design of transfer alignment algorithm in ship of horizontal axis attitude motion (수평축 자세운동이 있는 배에서의 전달정렬 알고리즘 설계)

  • Song, Ki-Won;Jeon, Chang-Bae;Kim, Hyun-Baek;Yoo, Jun
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.672-675
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    • 1996
  • This paper presents algorithm including Kalman filter for transfer alignment of velocity and quaternion matching method, when master inertial navigation system is a gimbled type and slave inertial navigation system is a strapdown type on a cruising ship which is naturally in motion of horizontal axis attitude. And relative attitudes are considered on a measurement equation for quaternion matching between master INS and slave INS.

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Multistep Quantum Master Equation Theory for Response Functions in Four Wave Mixing Electronic Spectroscopy of Multichromophoric Macromolecules

  • Jang, Seog-Joo
    • Bulletin of the Korean Chemical Society
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    • v.33 no.3
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    • pp.997-1008
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    • 2012
  • This work provides an alternative derivation of third order response functions in four wave mixing spectroscopy of multichromophoric macromolecular systems considering only single exciton states. For the case of harmonic oscillator bath linearly and diagonally coupled to exciton states, closed form expressions showing all the explicit time dependences are derived. These expressions can provide more solid physical basis for understanding 2-dimensional electronic spectroscopy signals. For more general cases of system-bath coupling, the quantum master equation (QME) approach is employed for the derivation of multistep time evolution equations for Green function-like operators. Solution of these equations is feasible at the level of 2nd order non-Markovian QME, and the new approach can account for inter-exciton coupling, dephasing, relaxation, and non-Markovian effects in a consistent manner.

Simulation of Manipulating Various Pulsed Laser Operations Through Tuning the Modulation Depth of a Saturable Absorber (포화 흡수체의 투과변조깊이 조절을 통한 다양한 펄스상태 조작 방법에 관한 전산 모사)

  • Gene, Jinhwa;Yeom, Dong-Il;Kim, Byoung Yoon
    • Korean Journal of Optics and Photonics
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    • v.28 no.6
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    • pp.351-355
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    • 2017
  • In this paper, we conduct a simulation of manipulating various pulsed laser operations through tuning the modulation depth of the saturable absorber in a laser cavity. The research, showing that various pulsed operations could be manipulated from Q-switching through Q-switched mode locking to mode locking by tuning the modulation depth of the saturable absorber in a cavity, has been studied by experimental means. We conduct a simulation with the Haus master equation to verify that these experimental results are consistent with expectations from theory. The time dependence of the gain was considered to express Q-switching fluctuation through applying a rate equation with the Haus master equation. Laser operation was manipulated from mode locking through Q-switched mode locking to Q-switching as modulation depth was increased, and this result agreed well with the theoretical expectation.

Vortex Filament Equation and Non-linear Schrödinger Equation in S3

  • Zhang, Hongning;Wu, Faen
    • Kyungpook Mathematical Journal
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    • v.47 no.3
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    • pp.381-392
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    • 2007
  • In 1906, da Rios, a student of Leivi-Civita, wrote a master's thesis modeling the motion of a vortex in a viscous fluid by the motion of a curve propagating in $R^3$, in the direction of its binormal with a speed equal to its curvature. Much later, in 1971 Hasimoto showed the equivalence of this system with the non-linear Schr$\ddot{o}$dinger equation (NLS) $$q_t=i(q_{ss}+\frac{1}{2}{\mid}q{\mid}^2q$$. In this paper, we use the same idea as Terng used in her lecture notes but different technique to extend the above relation to the case of $R^3$, and obtained an analogous equation that $$q_t=i[q_{ss}+(\frac{1}{2}{\mid}q{\mid}^2+1)q]$$.

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