X iv :1 70 4. 01 92 2v 1 [ m at h. C O ] 6 A pr 2 01 7 Sandwiches Missing Two Ingredients of Order Four José D. Alvarado Simone Dantas Dieter Rautenbach 1 Instituto de Matemática e Estat́ıstica, Universidade Federal Fluminense, Niterói, Brazil [email protected], [email protected] 2 Institute of Optimization and Operations Research, Ulm University, Ulm, Germany dieter.rautenbach@uni-ul...

In a recent paper, we introduced the simultaneous representation problem (defined for any graph class C) and studied the problem for chordal, comparability and permutation graphs. For interval graphs, the problem is defined as follows. Two interval graphs G1 and G2, sharing some vertices I (and the corresponding induced edges), are said to be “simultaneous interval graphs” if there exist interv...

Obstacle representations of graphs have been investigated quite intensely over the last few years. We focus on graphs that can be represented by a single obstacle. Given a (topologically open) polygon C and a finite set P of points in general position in the complement of C, the visibility graph GC(P ) has a vertex for each point in P and an edge pq for any two points p and q in P that can see ...

Sandwich structures have become effective structural elements for engineering applications due to their good design flexibility. Understanding the material behavior under static and dynamic loads, as well failure mechanisms of these sandwich structures, is great importance. This work evaluates fatigue bending epoxy resin specimens composites composed an core with glass fiber laminated faces. Th...