Global Existence and Stability to the Isothermal Gas Dynamics System with an Outer Force

En este artículo aplicamos el método clásico de viscosidad, junto con la aproximación de flujo y la teoría de la compacidad compensada, para obtener la existencia global de las soluciones entrópicas acotadas para el sistema dinámico de gas isotérmico con una fuente externa. Las estimaciones a priori de L∞ independientes del tiempo se prueban aplicando el principio máximo para un sistema parabólico acoplado no lineal adecuado de dos ecuaciones.In this paper, we apply the classical viscosity method, coupled with the flux approximation and the compensated compactness theory to obtain the global existence of the bounded entropy solutions for the isothermal gas dynamics system with an outer source. The a-priori time-independent L∞ estimates are proved by applying the maximum principle to a suitable nonlinear coupled parabolic system of two equations

The ant-parasitizing genus Pseudacteon Coquillett (Diptera: Phoridae) from China with description of three new species

The ant-parasitizing genus Pseudacteon Coquillett is reported for the first time in China. Three new species, P. quadrisetalis Liu & Cai, sp. n., P. obtusatus Liu & Cai, sp. n. and P. hexosetalis Liu & Wang, sp. n., are described and illustrated

Influence of unsymmetrical periodicity on extraordinary transmission through periodic arrays of subwavelength holes

Quadrate hole array is explored to study the influence of unsymmetrical periodicity on extraordinary optical transmission through periodic arrays of subwavelength holes. It is found that the transmission efficiency of light and the ratio between transmission efficiencies of horizontal and vertical polarized light can be continuously tuned by rotating the quadrate hole array. We can calculate out the transmission spectra (including the heights and locations of peaks) for any rotation angle $\theta$ with a simple theoretical model.Comment: 6 pages, 5 figure