Abstract Vortex cores in fluid mechanics are easy to visualize, yet difficult detect numerically. Precise knowledge of these allows dynamics researchers study complex flow structures and allow for a better understanding the turbulence transition process development evolution instabilities, name but few relevant areas. Various approaches such as Q, delta, swirling strength criterion have been pr...

In the present work a new controller called Particle Swarm Optimization (PSO) based state feedback gain (K) controller has been proposed for frequency regulation of a two area system and then its performance is compared with earlier designed controllers such as Linear Quadratic Regulator– Proportional Integral (LQR-PI) controller and Integral controller. The performance comparison has been done...

We analyse long–slit spectra of four early–type galaxies which extend from ∼ 1 to ∼ 3 effective radii: IC 1459, IC 3370, NGC 3379 and NGC 4105. We have extracted the full line–of–sight velocity distribution (in the case of NGC 3379 we also used data from the literature) which we model using the two–integral approach. Using two–integral modelling we find no strong evidence for dark haloes, but t...

A graph G is called integral or Laplacian integral if all the eigenvalues of the adjacency matrix A(G) or the Laplacian matrix Lap(G) = D(G)−A(G) of G are integers, where D(G) denote the diagonal matrix of the vertex degrees of G. Let Kn,n+1 ≡ Kn+1,n and K1,p[(p−1)Kp] denote the (n+1)-regular graph with 4n+2 vertices and the p-regular graph with p2 + 1 vertices, respectively. In this paper, we ...

The γ-ray light curves and spectra are presented for a set of theoretical Type Ia supernova models including deflagration, detonation, delayed detonation, and pulsating delayed detonations of Chandrasekhar mass white dwarfs as well as merger scenarios that may involve more than the Chandrasekhar mass and helium detonations of sub-Chandrasekhar mass white dwarfs. The results have been obtained w...

In this paper we sum over the spherical modes appearing in the expression for the Casimir energy of a conducting sphere and of a dielectric ball (assuming the same speed of light inside and outside), before doing the frequency integration. We derive closed integral expressions that allow the calculations to be done to all orders, without the use of regularization procedures. The technique of mo...