The angled bounce of a sports ball off a hard surface such as a typical tennis court has been the subject of many studies, for example Thorpe and Canaway (1986), Brody (1983), conferences and in-house reports. During play the tennis ball is hit at a variety of speeds, often with spin imparted to contact and bounce off the tennis court from a range of angles. The characteristics of these angled ...

Accurate casting to achieve a passive prosthesis is very important. Also, fabrication of a restoration because of the proximity implants remains a challenge. In this case report, one approach to this problem is discussed. Also, the goal of this study is analyzing fabrication an implant level cast with the help of angled abutment and acrylic resin cap. The advantage of the mentioned method is th...

The study examined the utility of stabilometric dimensions and explored whether the changes in sitting postures were manifested in functional measures of postural control. Eleven women participated in the study, which used 11 chair sitting postures: arms on laps or arms right angled; armrest at a height of 17, 20 and 23 cm; with or without backrest; slouch or straight back; legs right angled at...

For every orientable surface of finite negative Euler characteristic, we find a rightangled Artin group of cohomological dimension two which does not embed into the associated mapping class group. For a right-angled Artin group on a graph Γ to embed into the mapping class group of a surface S, we show that the chromatic number of Γ cannot exceed the chromatic number of the clique graph of the c...

Various species of high intensity highly charged state heavy ion beams with small emittance are required in many fields including particle physics, medical uses, inertial fusion, and simulator of space radiations. Direct Plasma Injection Scheme (DPIS), we have developed for several years, is a unique scheme to provide heavy ion beams to meet the above requirements. A high-density plasma created...

The paper presents the results of an experimental study a vertical wind turbine type Darrieus with frontal cylindrical guide vane unit. main goal research is to analyze influence geometry classical unit on active and passive zone turbine. aerodynamic scheme synthesized by classic runner vanes. Three different guiding devices model frontally located vanes have been studied. Their characteristics...

This article defines a pair of combinatorial operations on the combinatorial structure of compact right-angled hyperbolic polyhedra in dimension three called decomposition and edge surgery. It is shown that these operations simplify the combinatorics of such a polyhedron, while keeping it within the class of right-angled objects, until it is a disjoint union of Löbell polyhedra, a class of poly...