Transport coefficients of quantum plasma.
The two time Green's function method is applied to calculate the transport coefficients of an electron gas. The sequence of equations for Green's functions is derived. and it is shown that the results corresponding to the random phase approximation (including the exchange effects) can be obtained by terminating this sequence at the first stage. Proceeding to the second stage, one can quite naturally take the shielding effects and the plasma oscillation into account. Some discussions are made about the derivation of the kinetic equation for quantum plasma. (auth)
The generation and behavior of the fractal Koch array factor from a Kaiser window generator is studied. The main advantage of using Kaiser windows is that pattern parameters become much more flexible through altering the Kaiser window. The mainlobe width, current distribution, side-lobe ratio are now adjustable. Different reduced array structures can be obtained by using different threshold levels. Higher threshold values result in a highly reduced number of elements but they may highly distort the pattern and, hence, the multiband behavior. Finally, we study the effect of quantization of the feeding values. Quantization is necessary for implementation and simplification purposes. Several configurations of current distributions with the corresponding patterns are illustrated for different quantization levels. It is shown that moderate quantization keeps the same interesting similarity properties at several bands.