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21.
YAN  Sen-Lin 《理论物理通讯》2011,55(3):481-488
We study dynamics in two mutually coupling multi-quantum-well lasers. We carry out theoretical and numerical analysis of synchronization, anti-synchronization, in-phase locking in the two identical lasers but detuning, in detain. It is proved that the coupling level determines stability of the lasers by analyzing the eigenvalueequation. Critical case of locking is discussed via the phase difference equation. Quasi-period and stable states in the two lasers are investigated via varying the current, detuning and coupling level.  相似文献   
22.
According to the chemical kinetic model of lysogeny/lysis switch in Escherichia coli (E. coli) infected by bacteriophage λ, the entropy production rates of steady states are calculated. The results show that the lysogenic state has lower entropy production rate than lytic state, which provides an explanation on why the lysogenic state of λ phage is so stable. We also notice that the entropy production rates of both lysogenic state and lytic state are lower than that of saddle-point and bifurcation state, which is consistent with the principle of minimum entropy production for living organism in nonequilibrium stationary state. Subsequently, the relations between CI and Cro degradation rates at two bifurcations and the changes of entropy production rate with CI and Cro degradation are deduced. The theory and method can be used to calculate entropy change in other molecular network.  相似文献   
23.
自从1896年贝克勒尔(Becguerel)发现了天然性放射线以后,人们对物质结构的研究进入了微观领域(原子物理、核物理、粒子物理),随后进一步的研究表明,在放射性元素发生核衰变的过程中,由于核衰变产生的新核处于不稳定状态,总是要辐射出丫射线而达到稳定状态。这里的γ射线实质上是原子内放出的波长在0.1nm以下、带电量和静质量均为零、电离能力很弱、贯穿本领很强的高频电磁波——光子流。  相似文献   
24.
We report a numerical simulation of continuous terahertz beam induced transient thermal effects on static water. The terahertz wave used in this paper has a Gaussian beam profile. Based on the transient heat conduction equation, the finite element method (FEM) is utilized to calculate the temperature distribution. The simulation results show the dynamic process of temperature change in water during terahertz irradiation. After about 300 s, the temperature reaches a steady state with a water layer thickness of 5 mm and a beam radius of 0.25 mm. The highest temperature increase is 7 K/mW approximately. This work motivates further study on the interaction between terahertz wave and bio-tissue, which has a high water content.  相似文献   
25.
The evolutionary prisoner's dilemma game is investigated under different initial distributions for cooperators and defectors on scale-free networks with a tunable clustering coefficient. It is found that, on the one hand, cooperation can be enhanced with the increasing clustering coefficient when only the most connected nodes are occupied by cooperators initially. On the other hand, if cooperators just occupy the lowest-degree nodes at the beginning, then the higher the value of the clustering coefficient, the more unfavorable the environment for cooperators to survive for the increment of temptation to defect. Thereafter, we analytically argue these nontrivial phenomena by calculating the cooperation probability of the nodes with different degrees in the steady state, and obtain the critical values of initial frequency of cooperators below which cooperators would vanish finally for the two initial distributions.  相似文献   
26.
Many works have investigated the problem of reparameterizing rational B~zier curves or surfaces via MSbius transformation to adjust their parametric distribution as well as weights, such that the maximal ratio of weights becomes smallerthat some algebraic and computational properties of the curves or surfaces can be improved in a way. However, it is an indication of veracity and optimization of the reparameterization to do prior to judge whether the maximal ratio of weights reaches minimum, and verify the new weights after MSbius transfor- mation. What's more the users of computer aided design softwares may require some guidelines for designing rational B6zier curves or surfaces with the smallest ratio of weights. In this paper we present the necessary and sufficient conditions that the maximal ratio of weights of the curves or surfaces reaches minimum and also describe it by using weights succinctly and straightway. The weights being satisfied these conditions are called being in the stable state. Applying such conditions, any giving rational B6zier curve or surface can automatically be adjusted to come into the stable state by CAD system, that is, the curve or surface possesses its optimal para- metric distribution. Finally, we give some numerical examples for demonstrating our results in important applications of judging the stable state of weights of the curves or surfaces and designing rational B6zier surfaces with compact derivative bounds.  相似文献   
27.
The flutter instability and response of finite-span flexible plates in uniform flow are investigated experimentally. The effects of the plate aspect ratio on its dynamic responses are mainly analyzed. A hysteretic phenomenon is observed and can be described such that the plate flutters spontaneously as the flow velocity is greater than a critical value UC and the plate returns to its stable state as the flow velocity is slowly decreased to another critical one UD. We find that the aspect ratio has a greater effect on UC than on UD. The flutter frequency decreases and the amplitude increases with the increase in the flow velocity. When the flutter instability of the plate occurs, three typical flutter modes are identified and are associated with the aspect ratio and the flow velocity.  相似文献   
28.
周芳 《数学杂志》2012,32(2):281-295
本文讨论了一类三维非等熵半导体方程. 利用能量估计法, 证明了热平衡稳态解的存在唯一性.然后, 得到了Cauchy-Neumann问题光滑解的整体存在性以及当t→ +∞这种光滑解以指数速度收敛到稳定解, 改进了文献[12]的结果.  相似文献   
29.
Time-resolved photoluminescence (TRPL) was applied to investigate the transient process in GaP1-xNx (x = 0.12%) alloy. The filling, transferring and decay processes among nitrogen pairs are directly observed. The NN4 pair, either not present or only a small obscure peak under a proper excitation condition in the steady-state photoluminescence spectrum, is well resolved by TRPL.  相似文献   
30.
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