parameters as interception, infiltration, water storage on surface holes and soil profile, evapotranspiration are factors of loss water in a watershed and avoid from changing of precipitation to runoff. in this study, by use of hec-hms model and comparison of results of different methods of precipitation loss evaluation (initial and constant, green & ampt, scs curve number, deficit & constant a...

This paper studies the perturbations of system $${\dot{x}}=y$$ , $${\dot{y}}=-x$$ under arbitrary polynomial with switching curve $$y = x^m$$ where m is a positive integer. By analysing first order Melnikov function, we obtain lower bound and upper maximum number limit cycles bifurcating from period annulus if function not identically 0.

So far, the Elliptic Curve Cryptosystem(ECC) provides the highest strength-per-bit of any cryptosystem. The fast implementation of elliptic curve cryptosystem key algorithms, namely, Scalar Multiplication, is studied in this paper. The limitation of the traditional fixed point comb method is analyzed, and on the basis of the study improvement strategy of fixed-base comb algorithm of this propos...