Generally,the interaction between the East Asian subtropical westerly jet(EASWJ)and the East Asian summer monsoon(EASM)is regarded as a critical dynamic factor in the evolution of precipitation patterns in *** simulat...
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Generally,the interaction between the East Asian subtropical westerly jet(EASWJ)and the East Asian summer monsoon(EASM)is regarded as a critical dynamic factor in the evolution of precipitation patterns in *** simulation results from the transient climate evolution since the last glacial maximum,this study applies the multivariate empirical orthogonal function(MVEOF)analysis method to investigate the co-evolution relationships of the EASWJ and the EASM during the early,middle,and late Holocene,as well as their influence on precipitation patterns in *** results indicate that all the first MVEOF modes in different time periods of the Holocene display an out-of-phase relationship in the intensity anomaly between the EASWJ and the ***,the jet stream is wider and more tilted in the late *** the influence of secondary circulations formed during their co-evolution,a north-south dipolar precipitation pattern in eastern China(“flood in the south and drought in the north”or“drought in the south and flood in the north”)and an east-west dipolar pattern in northern China(“wet in the west and dry in the east”or“wet in the east and dry in the west”)are found in the early and middle Holocene,while in the late Holocene a regionally-consistent precipitation pattern is witnessed across the whole *** this mode,the precipitation in the middle and late Holocene is primarily dominated by trend *** second MVEOF mode reveals that the EASM weakens when the EASWJ shifts eastward and the jet steam axis shortens during the early Holocene,resulting in a north-south dipolar precipitation pattern in eastern China and a regionally-consistent pattern in northern *** the middle Holocene,dipolar precipitation patterns are also observed in both eastern China and northern China when the EASWJ moves northward and the EASM strengthens,while the moisture condition in North China is less pronounced,and vice *** the late Holocene,the intensity anomali
We propose a new numerical domain decomposition method for solving elliptic equations on compact Riemannian manifolds. One advantage of this method is its ability to bypass the need for global triangulations or grids ...
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Universal conductance fluctuations (UCF) are a hallmark of quantum interference in mesoscopic devices. According to the Altshuler-Lee-Stone theory, the amplitude of UCF remains independent of system parameters such as...
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The continuous miniaturization of 2D electronic circuits results in increased power density during device operation, leading to heat localization and placing higher demands on their performance thresholds. The risk to...
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Owing to its efficiency in solving some types of large-scale separable optimization problems with linear constraints, the convergence rate of the alternating direction method of multipliers(ADMM for short) has recentl...
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Owing to its efficiency in solving some types of large-scale separable optimization problems with linear constraints, the convergence rate of the alternating direction method of multipliers(ADMM for short) has recently attracted significant attention. In this paper, we consider the generalized ADMM(G-ADMM), which incorporates an acceleration factor and is more efficient. Instead of using a solution measure that depends on a bounded set and cannot be easily estimated, we propose using the original ?-optimal solution measure, under which we prove that the G-ADMM converges at a rate of O(1/t). The new bound depends on the penalty parameter and the distance between the initial point and the solution set, which is more reasonable than the previous bound.
The structural and elastic properties of multiferroic Ca3Mn2O7 with ferroelectric orthorhombic (O-phase) and paraelectric tetragonal structures (T-phase) have been studied by first-principles calculations within t...
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The structural and elastic properties of multiferroic Ca3Mn2O7 with ferroelectric orthorhombic (O-phase) and paraelectric tetragonal structures (T-phase) have been studied by first-principles calculations within the generalized gradient approximation (GGA) and the GGA plus Hubbard U approaches (GGA + U). The calculated theoretical structures are in good agreement with the experimental values. The T-phase is found to be antiferromagnetic (AFM) and the AFM O-phase is more stable than the T-phase, which also agree with the experiments. On these bases, the single-crystal elastic constants (Cijs) and elastic properties of polycrystalline aggregates are investigated for the two phases. Our elasticity calculations indicate Ca3Mn2O7 is mechanically stable against volume expansions. The AFM O-phase is found to be a ductile material, while the AFM T-phase shows brittle nature and tends to be elastically isotropic. We also investigate the influence of strong correlation effects on the elastic properties, qualitatively consistent results are obtained in a reasonable range of values of U. Finally, the ionicity is discussed by Bader analysis. Our work provides useful guidance for the experimental elasticity measurements of Ca3Mn2O7, and makes the strain energy calculation in multiferroic Ca3Mn2O7 thin films possible.
The effects of the Dzyaloshinski-Moriya (DM) interaction on the ground-state properties of the anisotropic XY chain in a transverse field have been studied by means of correlation functions and entanglement. Differe...
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The effects of the Dzyaloshinski-Moriya (DM) interaction on the ground-state properties of the anisotropic XY chain in a transverse field have been studied by means of correlation functions and entanglement. Different from the case without the DM interaction, the excitation spectra ek of this model are not symmetrical in the momentum space and are not always positive. As a result, besides the ferromagnetic (FM) and the paramagnetic (PM) phases, a gapless chiral phase is induced. In the chiral phase, the von Neumann entropy is proportional to log2 L (L is the length of a subchain) with the coefficient A ~ 1/3, which is the same as that of the XY chain in a transverse field without the DM interaction for 7 = 0 and 0 〈 h 〈 1. And in the vicinity of the critical point between the chiral phase and the FM (or PM) phase, the behaviors of the nearest- neighbor concurrence and its derivative are like those for the anisotropy transition.
We investigate the instability of two-layer Phillips model in this paper, which is a prototypical geophysical fluid model. Using the results of Guo and Strauss et al, we obtained linear instability implies nonlinear i...
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We investigate the instability of two-layer Phillips model in this paper, which is a prototypical geophysical fluid model. Using the results of Guo and Strauss et al, we obtained linear instability implies nonlinear instability provided the linearized system has an exponentially growing solution.
Based on rectangular partition and bilinear interpolation,we construct an alternating-direction implicit(ADI)finite volume element method,which combined the merits of finite volume element method and alternating direc...
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Based on rectangular partition and bilinear interpolation,we construct an alternating-direction implicit(ADI)finite volume element method,which combined the merits of finite volume element method and alternating direction implicit method to solve a viscous wave equation with variable *** paper presents a general procedure to construct the alternating-direction implicit finite volume element method and gives computational *** error estimate in L2 norm is obtained for the *** with the finite volume element method of the same convergence order,our method is more effective in terms of running time with the increasing of the computing *** experiments are presented to show the efficiency of our method and numerical results are provided to support our theoretical analysis.
Depending on the excitability of the medium, a propagating wave segment will either contract or expand to fill the medium with spiral waves. This paper aims to introduce a simple mechanism of feedback control to stabi...
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Depending on the excitability of the medium, a propagating wave segment will either contract or expand to fill the medium with spiral waves. This paper aims to introduce a simple mechanism of feedback control to stabilize such an expansion or contraction. To do this, we lay out a feedback control system in a block diagram and reduce it into a bare, universal formula. Analytical and experimental findings are compared through a series of numericalsimulations of the Barkley model.
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