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The purpose of this research is to study the upper critical field (H c2 ) of two-band superconductors by two-band Ginzburg -Landau approach. The analytical formula of H c2 included anisotropy of order parameter and anisotropy of effective-mass are found . The parameters of the upper critical field in ab-plane( but it has an unusual temperature dependence. Askerzade [10] study H c1 (T) and H c2 (T) for MgB 2 and nonmagnetic borocarbides by using the isotropy two-band Ginzberg-Landau model. He shows the complicate formula of critical magnetic field. In the H c2 consideration, his formula is less fit to experimental data than Drechsler 's [11]. In the recent work of Dao and Zhitomirsky [12] ,they study the effect of angular and temperature on upper critical field of MgB 2 determined with the anisotropy two-band Ginzberg-Landau theory. They found that the temperature variation of the ratio of two gaps is responsible for the upward temperature dependence of in-plane H c2 as well as for the deviation of its out-of-plane behavior from the standard angular dependence.In this paper, we study the upper critical magnetic field( 2 c H ) of anisotropy two-band swave superconductors by Ginzburg-Landau theory . We can find the formula of H c2 included anisotropy of order parameter and anisotropy of effective-mass . The upper critical field in abplane( ab c

The upper and lower critical field, and the critical field ratio of an anisotropic two-band magnetic superconductors in Ginzburg-Landau(GL) scenery is derived analytically. The temperature-dependent on the upper critical field is investigated and applied to Fe-based superconductors. We find that the very high value of zero-temperature upper critical field in Febased superconductors can be found in the negative differential susceptibility region. The temperature-dependent upper critical field is presented in two formulas as in the empirical view and in the GL two-band view that agrees with the experiment results.

As we calculate analytic to link the coefficient of third-order polynomial equations from raw data of an Asean to the SEIR model. The Reproductive index depending on the average incubation period and the average infection period and the coefficient polynomial equations fitted from raw are derived . We also consider the difference of the average incubation period as 5 days and 3 days with the average infection period as 10 day of an Asean. We find that the value of 0