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11.
Yong Huang Ke-Yong Zhu Jun Wang 《Journal of Quantitative Spectroscopy & Radiative Transfer》2011,112(14):2363-2371
The curved ray-tracing method is extended to radiative transfer in the graded index medium with diffuse gray boundary conditions instead of black boundary conditions and the pseudo-source adding method is extended to the case of the linear-anisotropic scattering medium with graded index from non-scattering medium. Furthermore, the equivalence of the two methods is verified by formulation derivation. As exact analytical solutions, both the methods have high accuracy and fast computational speed. The predicted temperature distributions and dimensionless radiative heat flux at radiative equilibrium are determined by the proposed methods, and the numerical results are compared with the data in references. The results show that the present methods have a good accuracy. Influences of various combinations of refractive index and boundary emissivities on the temperature distributions and dimensionless radiative heat flux are also investigated. 相似文献
12.
In this paper, we investigate a class of quadratic reversible Lotka-Volterra system of genus one with b=3/5. It is proved that the cyclicity of the period annulus under quadratic perturbations is equal to two. Moreover, we prove that the period function of its period trajectories is monotone increasing. 相似文献
13.
In this paper we study the problems of centers and isochronous centers and the local bifurcation of critical periods for a Liénard system with forth damping. Calculating the singular point values and period constants, we find all center conditions and isochronous center conditions. Moreover, the numbers of local critical periods bifurcating from centers and isochronous centers is obtained by computing the orders of weak centers. 相似文献
14.
Leonardo P. Bonorino Eduardo H.M. Brietzke Carlos A. Taschetto 《Journal of Differential Equations》2005,214(1):156-175
In this work we study the period function T of solutions to the conservative equation x″(t)+f(x(t))=0. We present conditions on f that imply the monotonicity and convexity of T. As a consequence we obtain the criterium established by C. Chicone and find conditions easier to apply. We also get a condition obtained by Cima, Gasull and Mañosas about monotonicity and, following some of their calculations, present results on the period function of Hamiltonian systems where H(x,y)=F(x)+n-1|y|n. Using the monotonicity of T, we count the homogeneous solutions to the semilinear elliptic equation Δu=γuγ-1 in two dimensions. 相似文献
15.
This paper presents an economic model of short-rotation forestry and shows that Lemke's linear complementarity algorithm can
be used to compute optimal sustainable harvesting strategies. As an example, we apply our method, using existing data, to
calculate optimal harvesting strategies for a plantation consisting of two interdependent species of trees. 相似文献
16.
Mansour Hashemi 《代数通讯》2018,46(9):4104-4119
17.
On the monotonicity of the period function of reversible centers On the monotonicity of the period function of reversible centers 下载免费PDF全文
Kuilin Wu 《Journal of Applied Analysis & Computation》2012,2(2):205-212
In this paper we study the period function of centers for a class of reversible systems and give a criteria to determine the monotonicity of the period functions. 相似文献
18.
J. Villadelprat 《Applied mathematics and computation》2010,216(7):1956-1964
In this note, motivated by the recent results of Wang et al. [Wang et al., Local bifurcations of critical periods in a generalized 2D LV system, Appl. Math. Comput. 214 (2009) 17-25], we study the behaviour of the period function of the center at the point (1,1) of the planar differential system
19.