A formal framework for the analysis of Hopf bifurcations in delay differential equations with a single time delay is presented. Closed-form linear algebraic equations are determined and the criticality of bifurcations is calculated by normal forms.

In this paper, Numerical solution of Differential-Algebraic equations (DAEs) with index-3 is considered by Pade approximation. We applied this method to two examples. First differential-algebraic equations (DAEs) with index-3 has been converted to power series by one-dimensional differential transformation, Then the numerical solution of equation was put into Pade series form. Thus we obtained ...

With any connected affine algebraic group G over an algebraically closed field K of characteristic zero, we associate another connected affine algebraic group D over K and a finite central subgroup F of D such that, up to isomorphism of algebraic groups, affine algebraic groups over K abstractly isomorphic to G are precisely of the form D/α(F )×Ks +, where α is an abstract automorphism of D and...

Various nonlinear, fixed-neighborhood techniques based on local statistics have been proposed in the literature for filtering noise in color images. We present adaptive-neighborhood filtering (ANF) techniques for noise removal in color images. The main idea is to find for each pixel (called the “seed” when being processed) a variable-shaped, variable-sized neighborhood that contains only pixels...

Chi-square tests are generally used for distinguishing purposes; however when they are combined to simultaneously test several independent variables, extra notation is required. In this study, the chi-square statistics in some previous works is revealed to be computed half of its real value. Therefore, the notion of Multi–Chi-square tests is formulated to avoid possible future confusions. In or...

We consider cubic boolean bent functions, each cubic monomial of which contains the same variable. We investigate canonical forms of these functions under affine transformations of variables. In particular, we refine the affine classification of cubic bent functions of 8 variables. 1 Preliminaries Let Vn be an n-dimensional vector space over the field F2, and Fn be the set of all boolean functi...

A new distinguishing property against block ciphers, called the division property, was introduced by Todo at Eurocrypt 2015. Our work gives a new approach to it by the introduction of the notion of parity sets. First of all, this new notion permits us to formulate and characterize in a simple way the division property of any order. At a second step, we are interested in the way of building dist...

This paper generalizes the notion of the backbone of a CNF formula to capture also equations between literals. Each such equation applies to remove a variable from the original formula thus simplifying the formula without changing its satisfiability, or the number of its satisfying assignments. We prove that for a formula with n variables, the generalized backbone is computed with at most n+1 s...

d-Monomial tests are statistical randomness tests based on Algebraic Normal Form representation of a Boolean function, and were first introduced by Filiol in 2002. We show that there are strong indications that the Gate Complexity of a Boolean function is related to a bias detectable in a d-Monomial test. We then discuss how to effectively apply d-Monomial tests in chosen-IV attacks against str...

In this paper two methods of designing Balanced Boolean functions for cryptographical transformations are presented. The first of them is based on using orthogonal nonlinear components. The second method realizes a combinatorial approach. Both methods provide high nonlinearity for the obtained functions and both of them operating with Algebraic Normal Form. The advantage of the first method is ...