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991.
张丽春  武月琴  赵仁 《中国物理》2004,13(6):974-978
Improving the membrane model by which the entropy of the black hole is studied, we study the entropy of the black hole in the non-thermal equilibrium state. To give the problem stated here widespread meaning, we discuss the (n 2)-dimensional de Sitter spacetime. Through discussion, we obtain that the black hole‘s entropy which contains two horizons (a black hole‘s horizon and a cosmological horizon) in the non-thermal equilibrium state comprises the entropy corresponding to the black hole‘s horizon and the entropy corresponding to the cosmological horizon. Furthermore, the entropy of the black hole is a natural property of the black hole. The entropy is irrelevant to the radiation field out of the horizon. This deepens the understanding of the relationship between black hole‘s entropy and horizon‘s area. A way to study the bosonic and fermionic entropy of the black hole in high non-thermal equilibrium spacetime is given.  相似文献   
992.
陆杭军  吴锋民  方允樟 《中国物理》2004,13(12):2038-2044
Chessboard-like substrates are introduced in this paper, in order to study the diffusion-limited aggregation (DLA)and the motion of poly-atoms on heterogeneous surfaces. The effect of morphology of such substrates upon the cluster aggregation is investigated using the Monte Carlo simulation. It is found that the growth process and the cluster morphology are governed by the energetic topography of the substrates. Our simulation also indicate that the island density and the fractal dimension of the clusters depend strongly on the substrate topography and the activation energy.  相似文献   
993.
氢气扩散火焰中辐射源项湍流脉动特征的PDF模拟   总被引:1,自引:0,他引:1  
采用κ-ε湍流模型、标量联合的概率密度函数(PDF)输运方程和层流火焰面模型相结合,模拟氢气自由扩散火焰中辐射源项湍流脉动特征.给出了主燃区内辐射源项湍流脉动的频率图.辐射源项的样本点分布集中,大约95%以上的样本落在其系综的±3倍方差以内,频谱图为单峰.  相似文献   
994.
邵静波  王玉兰  洪光 《物理实验》2004,24(8):31-32,35
应用F-P模型,阐述了半导体激光自混频干涉式传感器的干涉与调制过程,同时给出了相应的计算.  相似文献   
995.
压缩真空场与原子非线性作用过程中的纠缠与消纠缠   总被引:12,自引:0,他引:12       下载免费PDF全文
用Von Neumann熵研究了附加克尔介质的压缩真空场与二能级原子依赖强度耦合相互作用量子体系的量子纠缠特性.讨论了初始压缩真空场的压缩度以及克尔非线性作用的强度对该量子体系纠缠特性的影响.结果表明,克尔介质的非线性作用的强弱可以改变体系量子纠缠的周期性;在初始压缩度较大(r=5)时,克尔介质的非线性作用可导致原子与场持续地处于最大纠缠态,无消纠缠态或持续地处于消纠缠态. 关键词: 压缩真空态 克尔介质 依赖强度耦合J-C模型 Von Neumann熵 量子纠缠  相似文献   
996.
The entropy squeezing properties for a two-level atom interacting with a two-mode field via two different competing transitions are investigated from a quantum information point of view. The influences of the initial state of the system and the relative coupling strength between the atom and the field on the atomic information entropy squeezing are discussed. Our results show that the squeezed direction and the frequency of the information entropy squeezing can be controlled by choosing the phase of the atom dipole and the relative competing strength of atom-field, respectively. We find that, under the same condition, no atomic variance squeezing is predicted from the HUR while optimal entropy squeezing is obtained from the EUR, so the quantum information entropy is a remarkable precision measure for the atomic squeezing in the considered system.  相似文献   
997.
 建立了高超声速低温(HYLTE)喷管的响应面模型,样本点设计矩阵采用正交试验设计法构造,样本数据通过3维粘性NS方程计算喷管光腔耦合段的多组分混合流场获得。基于HYLTE喷管响应面模型,对喷管进行了多目标优化,定义了综合性能参数,优化后喷管混合性能显著改善,综合性能明显提高。计算表明,基于响应面模型的优化策略,能够满足喷管优化对计算精度和计算量的要求。运用多学科设计优化软件框架iSIGHT作为建模和优化的辅助工具,提高了优化设计的实现效率。  相似文献   
998.
K^- condensation and quark deconfinement phase transitions in neutron stars are investigated. We use the modified quark-meson coupling model for hadronic phase and the MIT bag model for quark phase. With the equation of state (EOS) solved self-consistently, we discuss the properties of neutron stars. We find that the EOS of pure hadron matter with condensed K- phase should be ruled out by the redshift for star EX00748-676, while EOS containing unpaired quark matter phase with B1/4 being about 180 MeV could be consistent with both this observation and the best measured mass of star PSR 1913 + 16. But if the recent inferred massive star among Terzan 5 with M 〉 1.68M is confirmed, all the present EOSes with condensed phase and deconfined phase would be ruled out.  相似文献   
999.
The sigma meson production in p + ^12C and p A- ^40Ca reactions at the incident energy Ep = 1.5 GeV is investigated within the Quantum Molecular Dynamics model. The simulation results indicate a distinctive A dependence of the sigma production, that is, the increase of A is followed by an increase of the production cross sections. We find that the σ meson production in proton-induced reactions is strongly medium-dependent, and the produced σ mesons decaying in a denser medium experience a stronger mass shift towards lower masses. This mass shift is an experimentally accessible observable in the final state pion pairs, which do not suffer from reabsorption by the surrounding nucleons. It is pointed out that the ratio of measured sigma cross sections as a function of the sigma invariant-mass from various reactions is a good probe to explore the existence of the σ meson in a dense nuclear environment.  相似文献   
1000.
A semi-direct sum of two Lie algebras of four-by-four matrices is presented, and a discrete four-by-four matrix spectral problem is introduced. A hierarchy of discrete integrable coupling systems is derived. The obtained integrable coupling systems are all written in their Hamiltonian forms by the discrete variational identity. Finally, we prove that the lattice equations in the obtained integrable coupling systems are all Liouville integrable discrete Hamiltonian systems.  相似文献   
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