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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Speed control of three-phase induction motors

Wong, D. January 1987 (has links)
No description available.
82

Methods and tool for implementing run-time reconfigurable FPGA designs

Shirazi, Nabeel January 1999 (has links)
No description available.
83

Microstructure and mechancial properties of rapidly solidified tool steels

Komatsubara, N. January 1989 (has links)
No description available.
84

Steady-state analysis of the static Kramer drive with alternative recovery systems

Al-Zahawi, B. A. T. January 1988 (has links)
No description available.
85

Computational methods for the design of multi-tooth-per-pole switched reluctance motors

Faiz, J. January 1988 (has links)
No description available.
86

Added power required by ships in bad weather

Baree, M. S. January 1985 (has links)
No description available.
87

A microprocessor thyristor-controlled DC drive incorporating regenerative braking

Mahmoud, M. El-S. January 1985 (has links)
No description available.
88

Speed control of wound-rotor induction motor using thyristors to control rotor external resistance

Smiai, Mohamed Salah January 1989 (has links)
No description available.
89

Unmanned aerial vehicle survivability the impacts of speed, detectability, altitude, and enemy capabilities

McMindes, Kevin L. 09 1900 (has links)
Warfighters are increasingly relying on Unmanned Aerial Vehicle (UAV) systems at all levels of combat operations. As these systems weave further into the fabric of our tactics and doctrine, their loss will seriously diminish combat effectiveness. This makes the survivability of these systems of utmost importance. Using Agent-based modeling and a Nearly Orthogonal Latin Hypercube design of experiment, numerous factors and levels are explored to gain insight into their impact on, and relative importance to, survivability. Factors investigated include UAV speed, stealth, altitude, and sensor range, as well as enemy force sensor ranges, probability of kill, array of forces, and numerical strength. These factors are varied broadly to ensure robust survivability results regardless of the type of threat. The analysis suggests that a speed of at least 135 knts should be required and that increases in survivability remain appreciable up to about 225 knts. The exception to speed's dominance is in the face of extremely high capability enemy assets. In this case, stealth becomes more important than speed alone. However, the interactions indicate that as both speed and stealth increase, speed yields a faster return on overall survivability and that speed mitigates increased enemy capabilities.
90

Evaluation of straight and swept ramp obstacles on enhancing deflagration-to-detonation transition in pulse detonation engines

Medina, Carlos A. 12 1900 (has links)
The use of detonations to achieve thrust in pulse detonation engines (PDEs) offers significant advantages in efficiency, simplicity, and versatility. An enabling mechanism for practical PDE implementation will likely utilize an efficient deflagration-todetonation transition (DDT) process. This method simplifies detonation generation, but the required length is prohibitive in many applications and limits the frequency of repeatability. Obstacles have historically been employed to minimize the DDT distance, but often result in significant total pressure losses that degrade the delivered efficiency advantages of PDEs. This thesis explored the use of straight and swept ramp obstacles to accelerate DDT while minimizing the overall pressure losses. Computer modeling examined three-dimensional disturbances caused by such obstacles. Experimental tests measured combustion shockwave speed, flame velocity, and flame front interactions with obstacles. Evaluations were completed for several straight ramp obstacle configurations in a modeled two-dimensional flow. The placement of consecutive ramps resulted in flame acceleration accompanied by significant pressure spikes approaching 500 psi. Although detonation was not verified across the instrumented section, experimental data prove that straight ramp obstacles successfully accelerate the DDT process. Computer modeling predicts that swept ramps may be even more effective by introducing streamwise vorticity with a relatively low pressure drop.

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