The stability analysis of sleeve stiffened pin-ended slender hollow columns of pipe or box section is performed in the present study. This is accomplished by using energy method, employing three terms in the assumed approximate deflection function. The lengthy and tedious algebraic manipulations involved in solving the relevant eigenvalue problem, necessitates employing the "MATHEMATICA" softwa...

Using a simple, annealed model, some of the key features of the recently introduced extremal optimization heuristic are demonstrated. In particular, it is shown that the dynamics of local search possesses a generic critical point under the variation of its sole parameter, separating phases of too greedy (non-ergodic, jammed) and too random (ergodic) exploration. Comparison of various local sear...

as one of the most promising distributed generation (dg) sources, wind power technology has been widely developed in recent years. doubly fed induction generator (dfig) is currently employed as one of the most common topologies for wind turbine generators (wtgs). this generator operates as a synchronous/asynchronous hybrid generators. therefore, it is necessary to power engineers find understan...