27 research outputs found
Spreads, arcs, and multiple wavelength codes
AbstractWe present several new families of multiple wavelength (2-dimensional) optical orthogonal codes (2D-OOCs) with ideal auto-correlation λa=0 (codes with at most one pulse per wavelength). We also provide a construction which yields multiple weight codes. All of our constructions produce codes that are either optimal with respect to the Johnson bound (J-optimal), or are asymptotically optimal and maximal. The constructions are based on certain pointsets in finite projective spaces of dimension k over GF(q) denoted PG(k,q)
On The Nield-Koznetsov Integral Function and Its Application to Airys Inhomogeneous Boundary Value Problem
In this work, we provide a solution to a two-point boundary value problem that involves an inhomogeneous Airys differential equation with a variable forcing function. The solution is expressed in terms of the recently introduced Nield-Koznetsov integral function, Ni(x), and another conveniently defined integral function, Ki(x). The resulting expressions involving these integral functions are then evaluated using asymptotic and ascending series
Cubic Curves, Finite Geometry and Cryptography
Some geometry on non-singular cubic curves, mainly over finite fields, is
surveyed. Such a curve has 9,3,1 or 0 points of inflexion, and cubic curves are
classified accordingly. The group structure and the possible numbers of
rational points are also surveyed. A possible strengthening of the security of
elliptic curve cryptography is proposed using a `shared secret' related to the
group law. Cubic curves are also used in a new way to construct sets of points
having various combinatorial and geometric properties that are of particular
interest in finite Desarguesian planes.Comment: This is a version of our article to appear in Acta Applicandae
Mathematicae. In this version, we have corrected a sentence in the third
paragraph. The final publication is available at springerlink.com at
http://www.springerlink.com/content/xh85647871215644