In this paper the authors consider the existence and uniqueness of the solution to the initial boundary value problem for a class of modified Zakharov equations, prove the global existence of the solution to the probl...
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In this paper the authors consider the existence and uniqueness of the solution to the initial boundary value problem for a class of modified Zakharov equations, prove the global existence of the solution to the problem by a priori integral estimates and Galerkin method.
An approach to deal with movings and collisions of arbitrary many discontinuities in the conservative front tracking method is developed. Using this approach one may develop an ＂all-purposed and robust＂ front-tracki...
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An approach to deal with movings and collisions of arbitrary many discontinuities in the conservative front tracking method is developed. Using this approach one may develop an ＂all-purposed and robust＂ front-tracking algorithm. The algorithm with this approach may have some inconsistency and thus will have 0（1） magnitude errors in some grid cells at sometimes. Nevertheless, these errors will be eliminated by the conservation-preserving property of the front-tracking method in the following computation. Numerical examples are presented to illustrate the efficiency of the approach.
Hydride precipitation in zirconium cladding materials can damage their integrity and *** temperature and material defects have a significant effect on the dynamic growth of *** this study,we have developed a phasefiel...
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Hydride precipitation in zirconium cladding materials can damage their integrity and *** temperature and material defects have a significant effect on the dynamic growth of *** this study,we have developed a phasefield model based on the assumption of elastic behaviour within a specific temperature range(613 K-653 K).This model allows us to study the influence of temperature and interfacial effects on the morphology,stress,and average growth rate of zirconium *** results suggest that changes in temperature and interfacial energy influence the length-to-thickness ratio and average growth rate of the hydride *** ultimate determinant of hydride orientation is the loss of interfacial coherency,primarily induced by interfacial dislocation defects and quantifiable by the mismatch degree *** escalation in interfacial coherency loss leads to a transition of hydride growth from horizontal to vertical,accompanied by the onset of redirection ***,redirection occurs at a critical mismatch level,denoted as qc,and remains unaffected by variations in temperature and interfacial ***,this redirection leads to an increase in the maximum stress,which may influence the direction of hydride crack *** research highlights the importance of interfacial coherency and provides valuable insights into the morphology and growth kinetics of hydrides in zirconium alloys.
It is showed that, as the Mach number goes to zero, the weak solution of the compressible Navier-Stokes equations in the whole space with general initial data converges to the strong solution of the incompressible Nav...
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It is showed that, as the Mach number goes to zero, the weak solution of the compressible Navier-Stokes equations in the whole space with general initial data converges to the strong solution of the incompressible Navier-Stokes equations as long as the later exists. The proof of the result relies on the new modulated energy functional and the Strichartz's estimate of linear wave equation.
The widely used energy transfer theory is a foundation of luminescence, in which the rates of Stokes and anti-Stokes processes have the same calculation formula. An improvement on the anti-Stokes energy transfer to ex...
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The widely used energy transfer theory is a foundation of luminescence, in which the rates of Stokes and anti-Stokes processes have the same calculation formula. An improvement on the anti-Stokes energy transfer to explain the fluorescence intensity reversal between the red and green fluorescence of Er（0.5）Yb（9.5）：FOV is reported in the present article. The range of the intensity reversal Z was measured to be 877. Dynamic processes for 16 levels were simulated. A coefficient, the improvement factor of the intensity ratio of Stokes to anti-Stokes processes in quantum Raman theory compared to classical Raman theory, is introduced to successfully describe the anti-Stokes energy transfer. A new method to calculate the distance between the rare earth ions, which is critical for the energy transfer calculation, is proposed. The validity of these important improvements is also proved by experiment.
One of the main challenges in modeling massive stars to the onset of core collapse is the computational bottleneck of nucleosynthesis during advanced burning stages. The number of isotopes formed requires solving a la...
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作者：
Yunkai ZhouJames R.ChelikowskyXingyu GaoAihui ZhouDepartment of Mathematics
Southern Methodist UniversityDallasTX 75275USA Center for Computational Materials
Institute for Computational Engineering and Scienceand Departments of Physics and Chemical EngineeringUniversity of TexasAustinTX 78712USA HPCC
Institute of Applied Physics and Computational MathematicsBeijing100094China LSEC
Institute of Computational Mathematics and Scientific/Engineering ComputingAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China
The Teter,Payne,and Allan“preconditioning”function plays a significant role in planewave DFT *** function is often called the TPA *** present a detailed study of this“preconditioning”*** develop a general formula ...
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The Teter,Payne,and Allan“preconditioning”function plays a significant role in planewave DFT *** function is often called the TPA *** present a detailed study of this“preconditioning”*** develop a general formula that can readily generate a class of“preconditioning”*** functions have higher order approximation accuracy and fulfill the two essential“preconditioning”purposes as required in planewave DFT *** general class of functions are expected to have applications in other areas.
We consider a two-state model which extends the exponential time-dependent Demkov model of non-adiabatic coupling to complex energies and interactions. Using the method of steepest descent, exact and practicable asymp...
We consider a two-state model which extends the exponential time-dependent Demkov model of non-adiabatic coupling to complex energies and interactions. Using the method of steepest descent, exact and practicable asymptotic expansions of the Hankel functions H(upsilon-j)(1)(lambda), H(upsilon-j)(2)(lambda) are obtained when \upsilon(j)\ and \lambda\ are large and of the same order. The semiclassical scattering two channel matrix within the strong-coupling Demkov model and embracing non-adiabatic parameters is derived. Closed form expressions for the transition probabilities, wich incorporate the effects of the classical turning point, are also derived. The matrix elements are shown to reduce correctly in known limiting cases. These include the case of exact symmetric resonance, the Landau-Zener and Callaway-Bartling model and the Stueckelberg noncrossing formula. In the case of a Hamiltonian matrix which is complex Hermitian on the real t axis, Berry has shown that the phenomenon of anholonomy arises as the physical manifestation of a non-integrable real geometric phase in adiabatic parallel transport round a closed circuit in real space. More recently Berry has reinterpreted this theory as arising from transport around a circuit in complex time. The geometric amplitude factor, which is simply the anholonomic phase corresponding to the connection on a complex fibre bundle, occurs naturally in the Demkov model which is an example of a closed system in parameter space driven by a complex Hermitian Hamiltonian. It is shown that the Berry phase phenomenon also involves contributions from both real and complex circuit adiabatic phases.
The aim of the present work is to generalize the method introduced by Güémez et al.[***.E52(1995)R2145]Using feedback scheme,two systems can be synchronized by signals or variables which come from the drivin...
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The aim of the present work is to generalize the method introduced by Güémez et al.[***.E52(1995)R2145]Using feedback scheme,two systems can be synchronized by signals or variables which come from the driving ***,it is possible for the systems to be synchronized by different driving signals which come from the third or fourth *** the unmasking procedure becomes more *** simulations are given.
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