Additive Number Theory can be best described as the study of sums of sets of integers. A simple example is given two subsets A and B of a set of integers, what facts can we determine about A + B where A + B := {a + b | a ∈ A and b ∈ B}? We will state a result regarding this example shortly. We note that a very familiar problem in Number Theory, namely Lagrange’s theorem that every nonnegative i...

This study investigates the effect of sub-phonemic variation in bilabial stop and sibilant fricative consonants on word identification. Recent research suggests that sub-phonemic variation in stop voicing contrasts influences lexical processing. The present study seeks further support for this view by examining listeners’ responses to synthetic speech varying along VOT and fricative place conti...

Within this paper we study the Minkowski sum of prisms (" Cephoids ") in a finite dimensional vector space. For a vector a ∈ R n with positive components we write ¯ a = (1 ¯ a 1 1 ¯ an) and denote by = ¯ a = {x ∈ R n || ¯ a, x 1 , x 0} the associated prism. We provide a representation of a finite sum of prisms in terms of inequalities.

Let SH denote the homothety class generated by a convex set S ⊂ R: SH = {a + λS | a ∈ R, λ > 0}. We determine conditions for the Minkowski sum BH + CH or the Minkowski difference BH ∼ CH of homothety classes BH and CH generated by closed convex sets B,C ⊂ R to lie in a homothety class generated by a closed convex set (more generally, in the union of countably many homothety classes generated by...

Fakhruddin has proved that for two lattice polygons P and Q any lattice point in their Minkowski sum can be written as a sum of a lattice point in P and one in Q, provided P is smooth and the normal fan of P is a subdivision of the normal fan of Q. We give a shorter combinatorial proof of this fact that does not need the smoothness assumption on P .

Under the extra assumption that the boundary is of class C this was proven by S. Nakajima (= A. Matsumura) in 1926 Theorem 1 solves this problem. For convex bodies with C boundaries and positive curvature Nakajima’s result was generalized by Chakerian [?] in 1967 to “relative geometry” where the width and brightness are measured with with respect to some convex body K0 symmetric about the origi...

TheMinkowski sum of two setsA,B ∈ IR, denotedA⊕B, is defined as {a+ b | a ∈ A, b ∈ B}. We describe an efficient and robust implementation for the construction of Minkowski sums of polygons in IR using the convolution of the polygon boundaries. This method allows for faster computation of the sum of non-convex polygons in comparison to the widely-used methods for Minkowski-sum computation that d...

We survey the connection between two results from rather different areas: failure of the 3-space property for local convexity (and other properties) within the category of quasiBanach spaces, and the irreducibility (in the sense of Minkowski difference) of large families of finite dimensional polytopes. Mathematics subject classification (2010): 46A16, 46B03, 52B15..

A global visibility map is a spherical image built to describe the complete set of global visible view directions for a surface. In this paper, we consider the computation of global visibility maps for regions on the boundary of a polyhedron. Both the self-occlusions introduced by a region and the global occlusions introduced by the rest of the surfaces on the boundary of the polyhedron are con...

In a partially ordered semigroup with the duality (or polarity) transform, it is possible to define a generalisation of continued fractions. General sufficient conditions for convergence of continued fractions are provided. Two particular applications concern the cases of convex sets with the Minkowski addition and the polarity transform and the family of non-negative convex functions with the ...