On some systems of regular functions.

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...

Some properties of the regular asynchronous systems

The asynchronous systems are the models of the asynchronous circuits from the digital electrical engineering. An asynchronous system f is a multi-valued function that assigns to each admissible input u : R → {0, 1}m a set f(u) of possible states x ∈ f(u), x : R → {0, 1}n. A special case of asynchronous system consists in the existence of a Boolean function Υ : {0, 1}n × {0, 1}m → {0, 1}n such t...

On Padé Approximation of Some Practical Functions

Additive Functions with Respect to Numeration Systems on Regular Languages

Additive numeration systems and the corresponding additive arithmetic functions have been studied from various points of view since the seminal papers of H. Delange [4, 5], where such functions were investigated for the usual q-adic numeration system. Later more exotic systems of numeration, such as general linear numeration systems [13, 14], especially such systems defined by linear recurring ...

On Some Fractional Systems of Difference Equations

This paper deal with the solutions of the systems of difference equations $$x_{n+1}=frac{y_{n-3}y_nx_{n-2}}{y_{n-3}x_{n-2}pm y_{n-3}y_n pm y_nx_{n-2}}, ,y_{n+1}=frac{y_{n-2}x_{n-1}}{ 2y_{n-2}pm x_{n-1}},,nin mathbb{N}_{0},$$ where $mathbb{N}_{0}=mathbb{N}cup left{0right}$, and initial values $x_{-2},, x_{-1},,x_{0},,y_{-3},,y_{-2},,y_{-1},,y_{0}$ are non-zero real numbers.