The goal of this study is to develop an objective methodology for estimating design floods, i.e. the flood peak discharge with return period T , at ungauged river catchments in Iceland. First, a regional flood frequency analysis is presented for estimating the T -year flood peak discharge with fixed duration D, Q(T,D), for poorly gauged and ungauged catchments. This is done by scaling a regiona...

There are two different physical models connecting the micro-geometry of a surface and its physical reflectance properties (BRDF). The first, Cook-Torrance, assumes geometrical optics: light is reflected and masked by the micro-facets. In this model, the BRDF depends on the probability distribution of micro-facets normals. The second, Church-Takacs, assumes diffraction by the micro-geometry. In...

Some basic results for Dirichlet series ψ with positive terms via log-convexity properties are pointed out. Applications for Zeta, Lambda and Eta functions are considered. The concavity of the function 1/ψ is explored and, as a main result, it is proved that the function 1/ζ is concave on (1,∞) . As a consequence of this fundamental result it is noted that Zeta at the odd positive integers is b...

In this paper, we present a new and robust method, general time-frequency distribution series (TFDS), for time-frequency analysis. We also introduce the concept of local interference and global interference and show that the local interference is important and the global interference is less important in TF analysis. The TFDS is very general. With only one parameter, order of the TFDS, one can ...

abstract variation of climatic elements could be estimated by standard deviation, coefficients of variation and so on. in iranian climatological literature, variations of climatic elements have main attention during last decades. meanwhile worldwide climatologist desired to study the characteristics of variations as well as the distribution of frequency average of these elements. in this paper,...

The information conveyed by the discrete Wigner-Ville representations of real, complex or analytic signals is highly redundant, each time-frequency location being related to others via non-obvious relationships. In this paper, we demonstrate that there also exists a large amount of linear relationships between time-frequency sample!;. This implies that a whole discrete Wigner-Ville representati...