In this paper we propose right-angled Artin groups as platform for a secret sharing scheme based on the efficiency (linear time) of the word problem. We define two new problems: subgroup isomorphism problem for Artin subgroups and group homomorphism problem in right-angled Artin groups. We show that the group homomorphism and graph homomorphism problems are equivalent, and the later is known to...

The flow hydrodynamics in a low specific speed radial pump-turbine reduced scale model is experimentally investigated under off-design operating conditions in generating mode. Wall pressure measurements, in the stator, synchronized with high-speed flow visualizations in the vaneless space between the impeller and the guide vanes using air bubbles injection are performed. When starting from the ...

The causes of resonance of a certain model pump-turbine unit during startup process were investigated in this article. A three-dimensional full flow path analysis model which contains spiral case, stay vanes, guide vanes, runner, gaps outside the runner crown and band, and draft tube was constructed. The transient hydraulic excitation force of full flow path was analyzed under five conditions n...

The radiometric force produced by a linear array of three radiometer vanes has been assessed numerically using an argon carrier gas and experimentally using air. The separation distance between the three vanes of the array was varied between 0 and 120 percent based on the height of an individual radiometer vane of 40mm. Qualitative agreement between the numerical and experimental results is sho...

Until recently, angled abutments have been the only solution to correcting the trajectory of the emergence profile of labially inclined implants in the maxilla. However, the clinical implications of angled abutments reveal several shortcomings. Newly designed angulated implants with a 12-degree restorative platform angulation are an alternative to angled abutments. The purpose of this article w...

This study was conducted to compare the success of implants restored with angled abutments to implants restored with standard abutments. Eighty-one implants in 24 patients were evaluated for up to 36 months. Measurements included probing depths, gingival level, gingival index, and mobility. No significant difference could be found for any of the parameters examined between implants restored wit...

In this paper we study topological invariants of a class of random groups. Namely, we study right angled Artin groups associated to random graphs and investigate their Betti numbers, cohomological dimension and topological complexity. The latter is a numerical homotopy invariant reflecting complexity of motion planning algorithms in robotics. We show that the topological complexity of a random ...

We show that a right-angled Artin group, defined by a graph Γ that has at least three vertices, does not split over an infinite cyclic subgroup if and only if Γ is biconnected. Further, we compute JSJ–decompositions of 1–ended right-angled Artin groups over infinite cyclic subgroups.

AIM The aim of the present study was to compare the success and complication rates of pediatric renal biopsy procedures between the angled tangential approach and the traditional approach. METHODS From 2004 to 2009 we prospectively enrolled pediatric patients who had undergone real time ultrasound guided renal biopsy with angled tangential approach. For comparison, we retrospectively reviewed...