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Using the evolution history of the universe, one can make constraint on the parameter space of dynamic dark energy models. We discuss two different parameterized dark energy models. Our results further restrict the combined constraints obtained from supernova and the first-year Wilkinson-microwave-anisotropy-probe observations. From the allowed parameter space, it is found that our universe will experience an eternal acceleration. We also estimate the bound on the physically relevant regions both in the re-inflationary and inflationary phases. 相似文献
324.
高速显微技术是一种在多学科中有着广泛应用潜力的研究手段。作者将高速显微摄影技术实际应用于金属切削、血液流变、气液双相流、液体气穴形成、高压玻壳汞继电器触点测量等研究领域,为这些研究领域提供了有价值的实验数据。文中分别介绍这些应用的实验情况,并给出了部分实验结果。 相似文献
325.
1990年原子能科学研究院建成一台百焦耳KrF激光器,最大能量输出达106焦耳。本文介绍激光器腔体主要结构参数的选定和激光实验。 相似文献
326.
模拟了强流电子束泵浦下,激光腔内的反应动力学过程,及不同注入时间、不同注入强度下注入锁定的激光生成、放大和输运过程。对实际非稳腔使用了一维伸展近似,并采用了预估—校正方法对光子输运方程进行求解。模拟结果表明,激光生成阶段,注入种子光源后,激光输出质量明显改善,使自发辐射部分受到了明显的抑制。得到了在不同注入强度、注入时间以及放大倍数下的激光输出的光谱特性,能量及各种效率的关系。发现锁定效果最佳时的注入时间出现在小信号增益峰值处。 相似文献
327.
Yi QinDavid L.B. Jupp Michael A. Box 《Journal of Quantitative Spectroscopy & Radiative Transfer》2002,74(6):767-781
As an accurate and efficient algorithm, the discrete-ordinate method (DOM) has been used to solve the radiative transfer problem of plane-parallel scattering atmosphere illuminated by a parallel beam, an idealized case of the sun, from above the atmosphere. In this paper, we extend this algorithm so that radiative problems of more general sources, such as parallel surface sources that illuminate with a parallel beam in any direction from any vertical position, and general surface sources that illuminate continuously in a hemisphere, can be solved. For a problem where intensity distributions are sought for a number of different sources within the same atmosphere-surface system, the intrinsic properties of DOM are used so that the time required for the solution for extra sources is reduced to a substantially small amount. In the case of parallel surface sources, numerical testing has shown that the amount can be reduced to as little as 15% of a full solution. Examples of applications are presented. 相似文献
328.
Green's function is a widely used approach for boundary value problems. In problems related to radiative transfer, Green's function has been found to be useful in land, ocean and atmosphere remote sensing. It is also a key element in higher order perturbation theory. This paper presents an explicit expression of the Green's function, in terms of the source and radiation field variables, for a plane-parallel atmosphere with either vacuum boundaries or a reflecting (BRDF) surface. Full polarization state is considered but the algorithm has been developed in such way that it can be easily reduced to solve scalar radiative transfer problems, which makes it possible to implement a single set of code for computing both the scalar and the vector Green's function. 相似文献
329.
ZONG Hong-Shi SUN Wei-Min 《理论物理通讯》2006,46(4):717-722
Based on the global color symmetry mode/ (GCM), a method for obtaining the quark loop effects on the dressed gluon propagator in GCM is developed. In the chiral limit, it is found that the dressed gluon propagator containing the quark loop effects in the Nambu-Goldstone and Wigner phases are quite different. In solving the quark self-energy functions in the two different phases and subsequent study of bag constant one shouM use the above dressed gluon propagator as input. The above approach for obtaining the current quark mass effects on the dressed gluon propagator is quite general and can also be used to calculate the chemical potential dependence of the dressed gluon propagator. 相似文献
330.
Yalong TianMichael A. Box 《Journal of Quantitative Spectroscopy & Radiative Transfer》2002,72(6):789-802
Radiative perturbation theory has proven to be a useful tool in radiative transfer calculations, especially in situations where repeated solution of the radiative transfer equation is required. So far however, its use has been restricted to non-polarized situations, including such applications as surface fluxes, UV indices, and the inversion of satellite radiance observations. Here, we extend the structure of radiative perturbation theory to incorporate the full Stokes formalism of polarization, to obtain the relevant equations for the first order term. This formalism will be applied to fluxes in a follow-up paper, and eventually to satellite observations. 相似文献