We tackle the challenge of efficiently learning the structure of expressive multivariate realvalued densities of copula graphical models. We start by theoretically substantiating the conjecture that for many copula families the magnitude of Spearman’s rank correlation coefficient is monotonic in the expected contribution of an edge in network, namely the negative copula entropy. We then build o...

Refractive index (RI) is a complex number comprising a real refractive index and an imaginary part: the absorption (or extinction) coefficient. The analysis of refractive index by the Surfoptic Imaging Reflectometer yields an approximation to the real part of the refractive index. The well established technique of ellipsometry, by contrast, can determine both the real refractive index and the e...

sedimentation in reservoirs reduces dams storage and makes many problems in their operation. therefore accurate computation of sediment volume is essential for appropriate design and optimum reservoir management during its operation. in this research long term field data of sefid-rood dam were used to check the sediment volume computed for ghezelozan basin. the computed volume of sediment by ra...

‎the global fom and gmres algorithms are among the effective‎ ‎methods to solve sylvester matrix equations‎. ‎in this paper‎, ‎we‎ ‎study these algorithms in the case that the coefficient matrices‎ ‎are real symmetric (real symmetric positive definite) and extract‎ ‎two cg-type algorithms for solving generalized sylvester matrix‎ ‎equations‎. ‎the proposed methods are iterative projection metho...

We propose a simple rule that generates scale-free networks with very large clustering coefficient and very small average distance. These networks are called simplex triangulation networks(STNs) as they can be considered as a kind of network representation of simplex triangulation. We obtain the analytic results of power-law exponent γ = 2 + 1 d−1 for d-dimensional STNs, and clustering coeffici...

in this paper, we reconstruct the hardy-littlewood’s inequality byusing the method of the weight coefficient and the technic of real analysis includinga best constant factor. an open problem is raised.