in the current research, wind energy potential at yazd synoptic stations, which contain wind data with 10 years statistic period and beyond, including yazd synoptic station (1976-2006), tabass (1987-2006), robate poshte badam (1992-2006), bafgh (1993-2006) and marvast (1997-2006), has been studied. wind data were obtained from the recorded data at yazd meteorology organization. the data were re...

In the present note, we address the question about behavior of L3-norm of the velocity field as time t approaches blow-up time T . It is known that the upper limit of the above norm must be equal to infinity. We show that, for blow-ups of type I, the lower limit of L3-norm equals to infinity as well. 1991 Mathematical subject classification (Amer. Math. Soc.): 35K, 76D.

1991 Mathematics subject classi cation: 11R11, 11D09 We study the density of the set of real quadratic fields for which the norm of the fundamental unit equals 1 inside the set of real quadratic fields containing elements of norm 1. A conjectural density is derived from a single heuristic assumption, and experimental data supporting this assumption are given. We finally discuss how close one ca...