The concepts of an automatic 3d grid generator for the solution of the semiconductor equations are presented. The grid generator allows to mix elements of different shapes. An algorithm for the refinement of a grid according to a given point density function is outlined. Local heuristics for the improvement of the quality of the elements with worst aspect ratio obtained during the refinement ar...

A new procedure for generating smooth uniformly clustered threedimensional structured elliptic grids is presented here which formulates three-dimensional boundary constraints by extending the two-dimensional counterpart1 presented by the author earlier. This fully automatic procedure obviates the need for manual specification of decay parameters over the six bounding surfaces of a given volume ...

This paper is concerned with the construction of optimized sparse grid approximation spaces for elliptic pseudodifferential operators of arbitrary order. Based on the framework of tensor-product biorthogonal wavelet bases and stable subspace splittings, we construct operator-adapted subspaces with a dimension smaller than that of the standard full grid spaces but which have the same approximati...

We show that under the assumption of Artin’s Primitive Root Conjecture, for all primes p there exist ordinary elliptic curves over Fp(x) with arbitrary high rank and constant j-invariant. For odd primes p, this result follows from a theorem which states that whenever p is a generator of (Z/lZ)∗/〈−1〉 (l an odd prime) there exists a hyperelliptic curve over Fp whose Jacobian is isogenous to a pow...

In a wind power generator using doubly fed induction generator (DFIG), the three-phase pulse width modulation (PWM) voltage source converter (VSC) is used as grid side converter (GSC) and rotor side converter (RSC). The standard linear control laws proposed for GSC provides not only instablity against comparatively large-signal disturbances, but also the problem of stability due to uncertainty ...

The use of wind turbines is increasing at very high rates in many countries around the world. Studies to evaluate the impact of connecting these new generation units to the existing power systems must be done. This paper proposes a wind energy conversion system for a grid connected permanent magnet synchronous generator (PMSG) and power electronic converter system. The model includes a PMSG mod...

Abstract: A permanent magnet (PM) synchronous generator system driven by wind turbine (WT), connected with smart grid via AC-DC converter and DC-AC converter, are controlled by the novel recurrent Chebyshev neural network (NN) and amended particle swarm optimization (PSO) to regulate output power and output voltage in two power converters in this study. Because a PM synchronous generator system...

The concept and implementation of the system for creating dynamic noise maps in PL-Grid infrastructure are presented. The methodology of dynamic acoustical maps creating is introduced. The concept of noise mapping, based on noise source and propagation models, was developed and employed in the system. The details of incorporation of the system to the PL-Grid infrastructure are presented. The re...

The security of many cryptographic schemes and protocols rests on the conjectured computational intractability of the discrete logarithm problem in some group 〈g〉 of prime order. Such schemes and protocols require domain parameters that specify 〈g〉 and a specific generator g. In this paper we consider the problem of computing information on the domain parameters from public keys selected unifor...