In this paper, the existence and uniqueness of the time-periodic solu-tions to the Ginzburg-Landau-BBM equations are proved by using a priori estimatesand Leray-Schauder fixed point theorem.
In this paper, the existence and uniqueness of the time-periodic solu-tions to the Ginzburg-Landau-BBM equations are proved by using a priori estimatesand Leray-Schauder fixed point theorem.
The mechanism by which spiral wave patterns appear in populations of Dictyostelium was probed experimentally by external chemical perturbation. Spiral waves, which often arise from the breakup of circular waves driven...
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The mechanism by which spiral wave patterns appear in populations of Dictyostelium was probed experimentally by external chemical perturbation. Spiral waves, which often arise from the breakup of circular waves driven by pacemakers, typically entrain those pacemakers. We studied these processes by resetting the waves with a spatially uniform pulse of extrinsic cyclic AMP. A pattern of spirals reappeared if resetting was early in the signaling stage, but only targets emerged following late resetting, in a manner analogous to cardiac defibrillation. This supports recent hypotheses that wave pattern selection naturally occurs by slow temporal variation of the excitability of the cells.
Summary form only given. We used the finite-difference time-domain method to solve Maxwell equations. More specifically, we applied the non-dissipative Yee's algorithm with a duality relation between the spatial r...
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In order to study melting of metals at high pressure, we propose a different method which can be thought of as a generalization of the well-known Lindemann law. One essential interesting feature is that neither the De...
In order to study melting of metals at high pressure, we propose a different method which can be thought of as a generalization of the well-known Lindemann law. One essential interesting feature is that neither the Debye temperature nor the Grüneisen coefficient are used in the theory. We find that the method based on first-principles calculations can be used to model the pressure dependence of the melting properties of metals very well. Predictions of the melting along the principal Hugoniot are calculated for Cu and Ta. In the case of Fe, the melting temperature is calculated at geophysically interesting pressures.
Dynamic behavior of coupled chaotic oscillators is investigated. A transition from high-dimensional hyperchaos to a generalized periodic splay state is found for extremely weak coupling. Chaotic nature of a single osc...
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Dynamic behavior of coupled chaotic oscillators is investigated. A transition from high-dimensional hyperchaos to a generalized periodic splay state is found for extremely weak coupling. Chaotic nature of a single oscillator and mutual resonant interactions are regarded to be responsible for this self-organized ordering. The functional phase distribution of the generalized splay state, which is essentially different from the equal-phase-separation distribution of the conventional splay states, can be well predicted by analyzing a single periodically forced oscillator.
Summary form only given. We used the finite-difference time-domain method to solve Maxwell equations. More specifically, we applied the non-dissipative Yee's algorithm with a duality relation between the spatial r...
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Summary form only given. We used the finite-difference time-domain method to solve Maxwell equations. More specifically, we applied the non-dissipative Yee's algorithm with a duality relation between the spatial representations of the electric and magnetic fields that represents both the differential and integral forms of Maxwell equations. The computational domain consists of 19 photonic lattice cells in the periodic structure for /spl epsi/ in the x and y direction and 8 mesh cells in the z direction. Each photonic lattice cell has been divided into 40/spl times/40 computational mesh cells, but due to duality of the discretization mesh, effectively we determined each field on only 20/spl times/20 points inside a photonic lattice cell. Periodic boundary conditions were used in all three directions. We observed the spatial distribution of the magnetic and electric fields and the movement of the mode resonance through the photonic band gap as the defect radius is changed. In addition, we determined the dependence of the localization (the field energy confined at the defect cell) on frequency (defect radius). We also found well localized defect modes.A defect in the form of an air hole with a modified radius was introduced in the center of a triangular lattice.
In Kaszlikowski et al. [Phys. Rev. Lett. 85, 4418 (2000)], it has been shown numerically that the violation of local realism for two maximally entangled N-dimensional (3<~N) quantum objects is stronger than for two...
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In Kaszlikowski et al. [Phys. Rev. Lett. 85, 4418 (2000)], it has been shown numerically that the violation of local realism for two maximally entangled N-dimensional (3<~N) quantum objects is stronger than for two maximally entangled qubits and grows with N. In this paper, we present the analytical proof of this fact for N=3.
There are many issues, including the high-velocity impact, the properties of materials in the mantle and the core of the earth, the controlled thermonuclear fusion of the laser-compressed pellets, and etc (in another ...
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There are many issues, including the high-velocity impact, the properties of materials in the mantle and the core of the earth, the controlled thermonuclear fusion of the laser-compressed pellets, and etc (in another word, geophysics, astrophysics, particles accelerator, fission and fusion reactor), which could be understood better if we had an accurate acknowledge on the thermodynamic properties/equation-of-state (EOS) for a condensed matter at high pressure and high temperature.
Experimentally, the thermodynamic properties of condensed matter at megabar pressures can now be probed in both static, low-temperature diamond-anvil-cell (DAC) experiments and in dynamic, high-temperature shock-wave experiments. The DAC technique is suitable for the ordinary laboratory hi which samples can be studied under controlled conditions. Using laser heating and refinements in instrumentation temperatures of about 3000 K can be reached up to pressure of the order of 200 - 300 GPa. Even higher temperature and pressure conditions can be achieved by shock-wave methods. Accordingly, there is an urgent need to develop theoretical method that can be used to facilitate the interpretation of the new data at extreme experimental conditions. In light of the tremendous technical advances in recent years the DAC and the shock-wave techniques have been brought closer together, it is also highly desirable to compare and evaluate the measurements made by the two techniques.
Theoretically, for the temperature range above 300 K and towards 100,000 K, a realistic ab initio prediction of the thermodynamic properties of materials still remains an important challenge to the theory of condensed matter. In this regard, the molecular dynamics simulation might in principle be the best tool, but the potential representing the interaction between the particles is somewhat too time-consuming to be calculated in the ab Initio framework. On the other hand, the quasi-harmonic theory indeed
We present a numerical study of the localized transverse magnetic (TM) defect modes in a two-dimensional, triangular-lattice photonic crystal. The sample consists of an array of circular, air cylinders in a dielectric...
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We present a numerical study of the localized transverse magnetic (TM) defect modes in a two-dimensional, triangular-lattice photonic crystal. The sample consists of an array of circular, air cylinders in a dielectric medium (GaAs). The defect modes were calculated by using a parallel version of the finite-difference time-domain method on the Yee mesh. To validate our computations the results for the transverse electric case were checked against experimental results and the numerical results using a different method. We study the spatial symmetry for TM modes, obtained by changing the dipole excitation frequency. Also, we vary the defect-cylinder radius to tune the resonant frequency across the band gap. The TM mode is found to be highly localized at the defect in the photonic lattice.
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