The control of variable-speed wind turbines that generate electricity from the kinetic energy involves subsystems need to be controlled simultaneously, namely, blade pitch angle controllers and generator torque controllers. presented study solves problem with multiple inputs outputs (MIMO), using method reinforcement learning–based Trust Region Policy Optimization, through which parameters both...

Coronal harmony in Kinyarwanda causes alveolar fricatives to become postalveolar preceding a postalveolar fricative within a stem. Alveolar and postalveolar stops, affricates and palatals block coronal harmony, but the flap and non-coronal consonants are reported to be transparent. Kinematic data on consonant production in Kinyarwanda were collected using electromagnetic articulography. The mea...

PURPOSE To evaluate any correlation between various foot angles and their respective American Orthopaedic Foot and Ankle Society (AOFAS) scores for pain, and the effectiveness of a medial arch orthosis. METHODS 81 children with bilateral symptomatic flatfoot were randomised into orthosis (n=55) and control (n=26) groups. The orthosis group consisted of 33 male and 22 female patients aged 36 t...

plate heat exchangers are widely used in industries due to their special characteristics, such as high thermal efficiency, small size, light weight, easy installation, maintenance, and cleaning. the purpose of this study is to consider the effect of depth, angle, and pitch of hemispheric chevrons on the convective heat transfer coefficient and pressure drop. in the simulation of the heat exchan...

Li, Yuwei. "Coupled computational fluid dynamics/multibody dynamics method with application to wind turbine simulations." PhD ii To my family iii ACKNOWLEDGMENTS I would like to express my greatest appreciation to my advisor, Associate Professor Pablo M. Carrica, who has been continuously supporting me throughout my Ph.D. research with his knowledge, experience, enthusiasm and patience. I am gr...

The blade pitch of a Vertical Axis Wind Turbine can have profound impact on the aerodynamic loading experienced by turbine. This in turn impacts structural loads and performance machine. In order to characterize effects changing pitch, studies are conducted with fixed offsets from neutral position open jet wind tunnel TU Delft. Measurements strain gages bonded turbine struts used estimate norma...

In this study, a computational fluid dynamics (CFD) model was developed to simulate the aerodynamic performance of National Renewable Energy Laboratory (NREL) offshore 5-MW baseline wind turbine with single rotor and full turbine. Using statistical methods, relation between pitch angle when speed is above rated analyzed; furthermore, other published data were compiled establish functional equat...

The pitch angle control is the most common means for adjusting the aerodynamic torque of the wind turbine when we rate wind speed, controlling various variables could be chosen, as generator power, generator speed and wind. As conventional pitch control customarily use PI controller, the mathematical model of the system should be well known. The controller design by the genetic algorithm is dev...

The use of disturbance models in wind turbine individual pitch control design to attenuate effects of persistent disturbances is investigated. Previous work has used individual pitch control and disturbance models to design controllers that reduce the blade loads at the frequencies associated with the rotor speed. This paper takes a similar approach of using a disturbance model within the H∞ de...

in order to help in the engineering design of rice harvesting machines, there is a need to have exact information concerning the physical and mechanical properties of rice stems. the cutting force for rice stems, therefore, was measured by designing and fabricating a static and dynamic shear test apparatus. the effects of moisture levels and the cross-sectional area of stem as well as the varie...