this study is focused on investigating the parameters of laser percussion drilling process of nickel-base super alloy inconel 718 with thickness of 1 mm. fiber laser with the power of 500 watts was used as the laser source. laser pulse frequency, duty cycle, laser power, focal point position, were assumed as the laser drilling process variables. the hole geometry features, i.e. entrance hole di...

post-mineralization activities may cause difficulties in the process of ore modeling in porphyry deposits. sungun, nw iran, is one of the porphyry copper deposits, in which dyke intrusions have made ore modeling more complicated than expected. among different kinds of dykes, two types were chosen and the consequent geostatistical analyses were applied on. in this study, simple directional vario...

Rectangular waveguide is one of the earliest types of transmission lines. Rectangular waveguide can be produced by hot extrusion process. In this paper, the hot extrusion process of CuZn5 rectangular waveguide was investigated by Finite Element Method (FEM). In addition, Genetic Algorithm (GA) was used to optimize the die geometry and process conditions to achieve the lowest magnitude of extrus...

The interaction of a cosmic string with a four-dimensional stationary black hole is considered. If a part of an infinitely long string passes close to a black hole it can be captured. The final stationary configurations of such captured strings are investigated. A uniqueness theorem is proved, namely it is shown that the minimal 2-D surface Σ describing a captured stationary string coincides wi...

The interaction of a cosmic string with a four-dimensional stationary black hole is considered. If a part of an infinitely long string passes close to a black hole it can be captured. The final stationary configurations of such captured strings are investigated. A uniqueness theorem is proved, namely it is shown that the minimal 2-D surface Σ describing a captured stationary string coincides wi...

Most hole filling approaches use techniques to fill up a hole first and then to smooth it. Very few tries rebuild features on the filled surface of the original 3D model. We propose an efficient hole-filling methodology which preserves sharp features of the geometry of the original model. The main idea is that we reconstruct feature curves in the missing parts of the given mesh before filling t...

We investigate thermodynamic curvatures of the Kerr and Reissner-Nordström (RN) black holes in spacetime dimensions higher than four. These black holes possess thermodynamic geometries similar to those in four dimensional spacetime. The thermodynamic geometries are the Ruppeiner geometry and the conformally related Weinhold geometry. The Ruppeiner geometry for d = 5 Kerr black hole is curved an...

We derive and solve the black hole attractor conditions of N = 8 supergravity by finding the critical points of the corresponding black hole potential. This is achieved by a simple generalization of the symplectic structure of the special geometry to all extended supergravities with N > 2. There are two classes of solutions for regular black holes, one for 1/8 BPS ones and one for the non-BPS. ...