This thesis presents the development of dynamic control strategies for the
brushless doubly-fed machine (BDFM). A simple open-loop scalar controller is first
investigated and its response is found to be oscillatory. Using the speed feedback
signal, an improved closed loop scalar control algorithm is designed. Steady state
performance is controlled...
The awareness of electric power quality has increased over the past decade as electronic equipment
has become more susceptible to power disturbances. The most disruptive power disturbances are voltage
sags and momentary interruptions and their effect on adjustable speed drives (ASDs) is studied in this
thesis.
Several solutions have been...
The links between forests, streamflow, and climate are poorly understood. Despite hundreds of studies over the past 60 years, fundamental questions of forests' effects on the hydrologic cycle remain unanswered. The hydrological cycle involves mutually-dependent biological and physical processes that operate at multiple scales of time and space, and this...
Carnitine, acetylcarnitine, and long-chain acylcarnitine concentrations
were determined for heart, brain, and liver of chick
embryos during various stages of development. The total carnitine
concentration was approximately the same in all three organs and
showed only small variations during development. Acetylcarnitine
was not detected in any organ until the seventeenth...
A highly flexible numerical simulation model for the performance
prediction of brushless dc drives is presented, which is capable of
investigating unbalanced and asymmetrical operating conditions as well
as drives with non-ideal parameters. Numerical speed-up procedures
allow for the investigation of pulse-width modulated (PWM) drives using
a personal computer. Experimental...
The purpose of this qualitative phenomenological study was to explore the successes of first generation, community college transfer students served by a TRiO/Student Support Services (TRiO/SSS) program. This study addresses a specific problem in higher education – there are a limited number of first generation transfer students who successfully matriculate...
The United States Air Force uses a test constructed by Air
Force personnel to test all individuals seeking entrance into Air
Force officer training programs. This test is titled "The Air Force
Officer Qualifying Test" (AFOQT). There are two major classes of
candidates who are required to take the test:...
An economic analysis and optimization of forest biomass processing and transportation at the operational level is presented. Renewable sources of energy have captured the interest of public and private institutions to develop cost-effective supply chains to reduce dependence on fossil fuels. The production of energy from forest harvest residues constitutes...
Samples of weathervane scallops taken on Oregon Department of
Fish and Wildlife cruises off Oregon waters during 1981-1982 were
analyzed for a comparative growth study. No evidence of internal
growth marks were found in the shell structure when analyzed by the
acetate peel technique. Internal growth lines formed in the...