The leaf surface is a stark environment for bacterial colonists with limited
availability of nutrients, water and protected niches. Despite these limitations, a
plethora of bacteria appear to have adapted ways to survive and flourish on leaf
surfaces. One mechanism of survival is the formation of biofilms. Biofilms are a...
Energy development is expanding rapidly across the western US. Negative effects have been documented for some wildlife, but consequences of development are unclear for other taxa, including raptors. We had the opportunity to examine effects of oil and natural gas development on two raptor species of conservation concern, ferruginous hawks...
Throughout the course of this thesis, I argue that the prose of David Foster Wallace, specifically his posthumously published novel The Pale King, inhabits a middle ground between universal sincerity and the particularized authenticity of postmodern irony. I examine Lionel Trilling's definitions of sincerity and authenticity before moving toward an...
This collection consists of autobiographical essays which center around my father,
my first husband, and my backyard. All of the pieces are recollections, and most occur
either from my study inside the house, or from the deck outside, looking at the yard. The
Preface is the story of how I...
The Vietnamese population that migrated to the United States is largely tied to South Vietnam. As the population settled, their strong opposition to communism has driven many in the community towards political alignment with the alt-right and even white nationalists. The proximity to these movements and their seeming tolerance of...
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Patricia Sakurai
The Vietnamese population that migrated to the United States is largely tied to
Mule deer (Odocoileus hemionus hemionus) and Rocky Mountain elk (Cervus canadensis nelsoni; hereafter elk) populations in northeast Oregon have declined in the past 10 to 20 years. Concurrent with these declines, cougar (Puma concolor) populations have apparently increased, leading to speculation that predation by cougars may be responsible for declining...
Normal adult rats absorbed and metabolized C¹⁴-labeled acetate
rapidly. The greatest percentage of the administered radioactivity
was recovered in the expired CO₂, however small amounts of radioactivity
were also found in the urine and feces. There were two rates
of C¹⁴O₂ elimination in normal adult rats. The small amount of...
The Brush less Doubly-Fed Machine (BDFM) has the potential to be a more cost effective replacement for conventional induction or synchronous machine drives. The BDFM has two stator windings: a power winding and a control winding. An electronic power converter of variable voltage and frequency is connected to the control...
This thesis covers the efforts of the design, analysis,
characteristics, and construction of a Linear Brush less Doubly-Fed
Machine (LBDFM), as well as the results of the investigations and
comparison with its actual prototype.
In recent years, attempts to develop new means of high-speed,
efficient transportation have led to considerable...
A brushless doubly-fed machine (BDFM) is a single-frame, self-cascaded
induction machine capable of operating in both the induction
and the synchronous modes. This thesis presents some important
advances concerning dynamic modeling, simulation and analysis of the
BDFM.
Initially, a two-axis model and its associated parameters are developed
and calculated. The...
This thesis presents both an analysis and simulations of a passively controlled variable-speed generator system, which can be applied for renewable energy sources such as wind turbines. Parallel connected passive/external resistors and inductors are connected to the slip rings of a wound rotor induction machine to provide an acceptable speed...
The continuing desire of industry to further improve process efficiency,
through tighter control and energy conservation, has prompted users to pay closer
attention to Adjustable Speed Drives (ASDs). The conventional ASDs consist of
induction or synchronous motors controlled by power electronic controllers through
the adjustment of supply frequency and line...
This thesis presents and examines the concept that the output of a wound-rotor induction generator (WRIG) can be limited by means of linking to external impedances for wind-turbine generating system application. An 80kW-WRIG is simulated as a model to examine the control of the output power vs. speed characteristic. Model...
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 evaluation of the stray-load losses in induction motors is an important part of the efficiency estimation process. However, stray-load losses have several components which are difficult to isolate and calculate. Consequently, they are more readily determined by test. IEEE Standard 112-1996 recommends the testing of electrical induction motors at...
Brushless Doubly Fed Machines (BDFM) have potential advantages in variable
speed generation and adjustable speed drive applications. The most significant of these
advantages is a reduction in the power electronic converter rating, and therefore a
reduction in overall system cost. Presently, efforts are being directed at optimizing the
design of...
The Motor Systems Resource Facility (MSRF) at Oregon State University presently conducts a variety of steady state tests on Motors and Generators, with ratings of upto 300Hp.(225kW), using a dynamometer. The dynamometer consists of an induction motor fed by a power electronic converter. A control computer uses a serial link,...
The thesis describes the preliminary studies on a
laboratory model of a magnetic elevator intended as part
of a system for circulating magnetic materials in chemical
reactors. A multiple coil laboratory model, controlled by
computer, was designed and constructed. Current measuring
transducers were used to monitor system performance and
study...
A 300 hp motor and generator testing facility is being completed at Oregon State University. The testing center is the largest independent testing facility west of the Mississippi River. This regional resource center will incorporate state-of-the-art features that set it apart from other testing facilities. An induction machine with a...
A project funded by the Southern California Edison (SCE) Company, Research
Center of Irwindale, California, has supported the development of a performance and
parameter prediction software program for use during the refurbishment of large
synchronous machines, turbine generators, and synchronous condensers. The computer
program was developed for SCE to allow...