Title of Document: LONGITUDINAL SPACE-CHARGE WAVES INDUCED BY ENERGY MODULATIONS Brian L. Beaudoin, Master of Science, 2008 Directed By: Professor Patrick G. O’Shea and Professor Rami A. Kishek Department of Electrical and Computer Engineering High intensity beams that are space-charge dominated are important for applications such as free electron lasers that require high intensity and low emit...

Electronic Orientation Aids (EOA) usually guide visually impaired pedestrians using turn-by-turn instructions. However, several studies have demonstrated that mental representations of space seem difficult to build when turn-by-turn instructions only are provided. This is a crucial point as getting an accurate spatial representation of the surroundings can make the difference between successful...

A fast photodiode was demonstrated to be able to extract the turn by turn photon beam profile information of electron storage rings if the photodiode was operated at the saturated region. When applied this method to a 1.3 GeV synchrotron light source with 200 mA beam current, the synchrotron radiation intensity is not intense enough to saturate the photodiode. To apply this method to the type o...

This paper proposes an AC-DC converter with the application of active type soft switching techniques. Boost converter with active snubber is used to achieve power factor correction. Boost converter main switch uses Zero Voltage Transition switching for turn on and Zero Current Transition switching for turn off. The active snubber auxillary switch uses Zero Current Switching for both turn on and...

Abstract The fabrication and I-V characteristics of the novel AlGaN/GaN field effect diode are reported. This diode has a distinguishing anode structure and the relatively thick AlGaN barrier layer in contrast a conventional field-effect Schottky barrier diode (FESBD). By using fluoride-based plasma treatment, we could reduce its turn-on voltage to 0 V and decrease its leakage current at the re...

Copy Summary: It has been found that humans not only tend to avoid the middle routes and prefer the peripheral routes among multiple choices, but also rely on the ‘initial segment strategy’ to select the route. In this paper, we propose a new heuristic which humans apply during route selection: Participants prefer the route whose initial direction lies in the direction of their final destinatio...

The objective of this traffic safety investigation was to find critical road sections using Postand Preaccident analysis approaches. The Post-accident approach analyzes the effect of road geometric characteristics on accident rate. The study was based on accident and road maintenance data in Western Sweden. A total of 2912 accidents from 2000 to 2005 on 1615 km median-separated roads was collec...

Navigation aids provide users with a route as a sequence of turn by turn instructions, each of which guides the user from one decision point to the next. Along the extensive research on enriching navigation aids with the elements of spatial cognition, this research provokes the idea of including cognitive subdivisions of space in outdoor navigation. As the first step, we present the results of ...

The paper presents a simple soft-switching forward DC-DC converter suitable for low power applications. A lossless passive turn-off snubber is employed to provide zero voltage turn off of the switch as well as transformer reset. Moreover, the choice to operate the converter in discontinuous conduction mode (DCM), while providing zero current turn on of the switch, also allows to simplify the to...