A (1,-1)-matrix will be called a bent type matrix if each row and each column are bent sequences. A similar description can be found in Carlisle M. in which the authors use the properties of bent type matrices to construct a class of bent functions. In this paper we give a general method to construct bent type matrices and show that the bent sequence obtained from a bent type matrix is a genera...

Failure investigation was conducted on a bleed air connector of an aircraft engine that developed opening during service. The fabricated tubular structure wherein the flanges were circumferentially welded to bent pipe both ends. and made austenitic stainless steel AISI 321. Fractography study confirmed had failed by fatigue mechanism. Fatigue crack initiated at one weld joints. exact location i...

Bent functions as optimal combinatorial objects are difficult to characterize and construct. In the literature, bent idempotents are a special class of bent functions and few constructions have been presented, which are restricted by the degree of finite fields and have algebraic degree no more than 4. In this paper, several new infinite families of bent functions are obtained by adding the the...

This paper presents the post-forming limits of polyamide 6 carbon (CF/PA6) thermoplastic tubes to facilitate design and process optimisation bent tubular CF/PA6 part manufacturing. Straight can be post-formed using rotary draw bending at elevated temperature achieve desired curvatures. Forming are predicted based on their winding angles, tube geometry, radius, presented as relation between angl...

In this paper, we consider the characterization of the bentness of quadratic Boolean functions of the form f(x) = ∑ m 2 −1 i=1 Tr n 1 (cix 1+2ei)+Tr n/2 1 (cm/2x 1+2n/2), where n = me, m is even and ci ∈ GF (2 ). For a general m, it is difficult to determine the bentness of these functions. We present the bentness of quadratic Boolean function for two cases: m = 2p and m = 2pq, where p and q ar...

We obtain the nonexistence of generalized bent functions (GBFs) from (\ZZ/t\ZZ)^n to \ZZ/t\ZZ (called type [n,t]), for a large new class. Specifically, by showing certain quadratic norm form equations have no integral points, we obtain the universal nonexistence of GBFs with type [n, 2p^e] for all sufficiently large p with respect to n and (p-1)/\ord_2(p), and by computational methods with a we...

In this paper we investigate properties of generalized bent Boolean functions and 2-bent (i.e., negabent, octabent, hexadecabent, et al.) Boolean functions in a uniform framework. We generalize the work of Stǎnicǎ et al., present necessary and sufficient conditions for generalized bent Boolean functions and 2-bent Boolean functions in terms of classical bent functions, and completely characteri...

In this paper we characterize (octal) bent generalized Boolean functions defined on Z2 with values in Z8. Moreover, we propose several constructions of such generalized bent functions for both n even and n odd.

A Boolean function with an even number n = 2k of variables is called bent if it is maximally nonlinear. We present here a new construction of bent functions. Boolean functions of the form f(x) = tr(α1x1 + α2x2), α1, α2, x ∈ F2n , are considered, where the exponents di (i = 1, 2) are of Niho type, i.e. the restriction of xi on F2k is linear. We prove for d1 = 2 + 1 and d2 = 3 · 2k−1 − 1, d2 = 2 ...