On volume quotient functions

On the Complete Monotonicity of Quotient of Gamma Functions

In this paper, we concern with a conjecture involving the ratio of two gamma functions posed by Qi, Guo and Chen [Math. Inequal. Appl. 9(3)(2006), 427-436]. We also generalize a result of Qi [Theorem 2, J. Comput. Appl. Math. 214 (2008), 610-616]. Mathematics subject classification (2010): 33B15, 26A48, 26A51.

Fibers, Surjective Functions, and Quotient Groups

The Rayleigh Quotient of Bent Functions

The Rayleigh quotient of a bent function is an invariant under the action of the orthogonal group, and it measures the distance of the function to its dual. An efficient algorithm is derived that generates all bent functions of given Rayleigh quotient. The Rayleigh quotient of some bent functions obtained by primary (Maiorana McFarland, Dillon) or secondary (direct and indirect sum) constructio...

study of hash functions based on chaotic maps

توابع درهم نقش بسیار مهم در سیستم های رمزنگاری و پروتکل های امنیتی دارند. در سیستم های رمزنگاری برای دستیابی به احراز درستی و اصالت داده دو روش مورد استفاده قرار می گیرند که عبارتند از توابع رمزنگاری کلیددار و توابع درهم ساز. توابع درهم ساز، توابعی هستند که هر متن با طول دلخواه را به دنباله ای با طول ثابت تبدیل می کنند. از جمله پرکاربردترین و معروف ترین توابع درهم می توان توابع درهم ساز md4, md...

On Differentiability of Volume Time Functions

We show differentiability of a class of Geroch’s volume functions on globally hyperbolic manifolds. Furthermore, we prove that every volume function satisfies a local anti-Lipschitz condition over causal curves, and that locally Lipschitz time functions which are locally antiLipschitz can be uniformly approximated by smooth time functions with timelike gradient. Finally, we prove that in stably...