This paper proposes a cluster partitioning technique to calculate improved upper bounds to the optimal solution of maximal covering location problems. Given a covering distance, a graph is built considering as vertices the potential facility locations, and with an edge connecting each pair of facilities that attend a same client. Coupling constraints, corresponding to some edges of this graph, ...

Optical scanning holography (OSH) is an incoherent digital holography technique, with wide applications such as optical microscopy, remote sensing etc [1]. It uses a Fresnel zone plate (FZP) to record the volume information of an object by two-dimensional (2D) raster scanning. For optical image processing, it is highly desirable that the edge information can be extracted via reconstruction. Var...

an injective map f : e(g) → {±1, ±2, · · · , ±q} is said to be an edge pair sum labeling of a graph g(p, q) if the induced vertex function f*: v (g) → z − {0} defined by f*(v) = (sigma e∈ev) f (e) is one-one, where ev denotes the set of edges in g that are incident with a vetex v and f*(v (g)) is either of the form {±k1, ±k2, · · · , ±kp/2} or {±k1, ±k2, · · · , ±k(p−1)/2} u {k(p+1)/2} accordin...

We investigate the problem of packing and covering odd (u, v)-trails in a graph. A (u, v)-trail is a (u, v)-walk that is allowed to have repeated vertices but no repeated edges. We call a trail odd if the number of edges in the trail is odd. Let ν(u, v) denote the maximum number of edge-disjoint odd (u, v)-trails, and τ(u, v) denote the minimum size of an edge-set that intersects every odd (u, ...

Atacama Submillimeter Telescope Experiment Polarimeter is an integrated module that enables magnetic field imaging on the 10m dish telescope. APol works in combination with a transition edge sensor bolometer camera covering 245 to 370 GHz. Herein we introduce the design concept and latest progress.

We prove that any finite simple graph can be covered by three of its odd subgraphs, and we construct an infinite sequence of graphs where an edge-disjoint covering by three odd subgraphs is not possible. c © ??? John Wiley & Sons, Inc.

Visual receptive fields have been mapped with moving patterns in the cat's retinal ganglion cells. A small, general-purpose computer was used to collect a matrix of 2500 data points covering a 25 degrees -by-25 degrees region of space. The analysis of 40 units reveals the existence of many nonconcentric receptive fields and also the presence of line and edge detectors.

A decomposition of Kn \L, the complete graph of order n with a subgraph L (called the leave) removed, into edge disjoint copies of a graph G is called a maximum packing of Kn with G if L contains as few edges as possible. A decomposition of Kn U P, the complete graph union a graph P (called the padding), into edge disjoint copies of a graph G is called a minimum covering of Kn with G if P conta...

We show that if pn log n the binomial random graph Gn,p has an approximate Hamilton decomposition. More precisely, we show that in this range Gn,p contains a set of edge-disjoint Hamilton cycles covering almost all of its edges. This is best possible in the sense that the condition that pn log n is necessary.