Recently, Guibas et al. 10 studied deformable necklaces – flexible chains of balls, called beads, in which only adjacent balls can intersect. In this paper, we investigate the problem of covering a necklace by cylinders. We consider several problems under different optimization criteria. We show that optimal cylindrical cover of a necklace with n beads in R by k cylinders can be computed in pol...

Laminar natural convection from an array of horizontal isothermal cylinders confined between two vertical walls, at low Rayleigh numbers, is investigated by theoretical and numerical methods. The height of the walls is kept constant, however, number of the cylinders and their spacing, the distance between the walls and Rayleigh number have been varied. The optimal spacing (confining walls) and ...

The risks of ferromagnetic compressed gas cylinders becoming projectiles in an MR environment are well known (12). The recent death of a child from such an incident reinforces the potential for disaster (3).

The stability of viscous flow between rotating cylinders in the presence of a constant axial magnetic field is considered. The boundary conditions for general conductivities are examined. It is proved that the Principle of Exchange of Stabilities holds at zero magnetic Prandtl number, for all Chandrasekhar numbers, when the cylinders rotate in the same direction, the circulation decreases outwa...

in this paper, first design and analysis history of full metal cng cylinders for vehicle are investigated. next with respect to the cng worldwide standards, a full metal type cylinder is designed and analysed. then the numerical analysis results and practical results are compared, and the correctness of the investigation is verified. in the end, the most suitable alloy with respect to the dimen...

In this paper, free and forced vibration analysis of functionally graded material cylinders was carried out by mesh-free and finite element method. In this analysis, MLS shape functions are used for approximation of displacement field in the weak form of motion equation and essential boundary conditions are imposed by transformation method. Resulted set of differential equations are solved usin...

Background and Aim: Recurrent caries and low bond strength are the main causes of composite restorations failure. This study sought to assess the effect of chlorhexidine (CHX) on micro-shear bond strength (MSBS) to dentin of a fourth generation adhesive system and a universal bonding agent after aging. Materials and Methods: This in vitro study used 32 extracted third molars and 3-5mm thick de...

An infinite row of periodically spaced, identical rigid circular cylinders is excited by an acoustic line source, which is parallel to the generators of the cylinders. A method for calculating the scattered field accurately and efficiently is presented. When the cylinders are sufficiently close together, Rayleigh–Bloch surface waves, which propagate energy to infinity along the array are excite...