In recent years, there has been a fast growth in wind energy conversion system (WECS). There are two general types of wind turbines in WECS: fixed speed wind turbines and varying speed wind turbines.Permanent magnet synchronous generator (PMSG) is one of the most attractive generators for the varying speed turbine WECS.In this paper, a fuzzy controller is proposed to control the current source ...

Digital Simulation and implementation of a Power Factor Correction (PFC) half bridge converter based adjustable speed voltage controlled VSI fed PMBLDC motor is presented in this paper. A single-phase AC-DC converter topology based on the half bridge converter is employed for PFC which ensures near unity power factor over wide speed range. The proposed speed control scheme has the concept of DC...

In this paper I discuss three different methods to speed up midpoint-offset domain downward continuation based migration. I compare the migration results with the more standard downward continuation method. I show that a factor of two speed up is achievable with little discernible loss in image quality. In addition I show that for velocity analysis purposes a factor of three to four speed up is...

BACKGROUND Over the past decade, use of leukocyte platelet-rich fibrin (L-PRF) has gained tremendous momentum in regenerative dentistry as a low-cost fibrin matrix used for tissue regeneration. This study characterizes how centrifugation speed (G-force) along with centrifugation time influence growth factor release from fibrin clots, as well as the cellular activity of gingival fibroblasts expo...

We propose a hybrid method for forecasting the wind speed. The wind speed data is first decomposed into intrinsic mode functions (IMFs) with empirical mode decomposition. Based on the partial autocorrelation factor of the individual IMFs, adaptive methods are then employed for the prediction of IMFs. Least squares-support vector machines are employed for IMFs with weak correlation factor, and a...

this paper describes the theoretical and experimental investigations of the key components and also the performance analysis of a rotary wheel for using as a solid desiccant dehumidifier and also indirect evaporator cooling system. solid desiccants have long been used in dehumidification and cooling systems for energy efficiency or reduce electricity. although many mathematical models on the ro...

the non-uniformity factor is used for correction of the formulas obtained from the one-dimentional fluid flow method in a centrifugal impeller pump. the variations of radial velocity at the outlet of five centrifugal impellers with the specific speed of about ns =50 are calculated at design point by using two-dimentional potentional flow method for an invisid fluid. on the other hand~ the varia...

We propose simple transformation of the hidden states in variational Bayesian factor analysis models to speed up the learning procedure. The speed-up is achieved by using proper parameterization of the posterior approximation which allows joint optimization of its individual factors, thus the transformation is theoretically justified. We derive the transformation formulae for variational Bayesi...