Gravitational search algorithm (GSA) is one of the newest swarm based optimization algorithms, which has been inspired by the Newtonian laws of gravity and motion. GSA has empirically shown to be an efficient and robust stochastic search algorithm. Since introducing GSA a convergence analysis of this algorithm has not yet been developed. This paper introduces the first attempt to a formal conve...

Gravitational search algorithm (GSA) is one of the newest swarm based optimization algorithms, which has been inspired by the Newtonian laws of gravity and motion. GSA has empirically shown to be an efficient and robust stochastic search algorithm. Since introducing GSA a convergence analysis of this algorithm has not yet been developed. This paper introduces the first attempt to a formal conve...

Hydrodynamics analyses as a part of the APEX (advanced power extraction) study demonstrates the potential application of applying swirling thick liquid walls to innovative confinement concepts such as field reversed configuration (FRC), spherical torus (ST) and heavy-ion fusion (HIF). This paper addresses the design and the hydrodynamic aspects of fusion relevant swirling flow including 3-D vel...

The circumnuclear disk and ionized gas filaments as remnants of tidally disrupted clouds Abstract. Sticky particle calculations indicate that a coherent structure , a dispersion ring, forms when a cloud on a low angular momentum orbit passes close to the dynamical center of a potential containing a point mass. The cloud is tidally stretched and differentially wrapped, and dissipation in shocks ...

We present the results of a combined study of ASCA and ROSAT observations of the distant cluster Abell 2390. For this cluster a gravitational arc as well as weak lensing shear have been previously discovered. We determine the surface brightness profile and the gas density distribution of the cluster from the ROSAT PSPC and HRI data. A combined spatially resolved spectral analysis of the ASCA an...