2009/2010 YIDP Abstracts
Young Investigator Development Program
Combiner Design for Reducing Sidelobes in LINC Power Amplifiers(Electrical and Computer Engineering / School of Engineering and Computer Science)
This project focuses on the design of power amplifiers for high linearity and efficiency to be used in microwave radar systems for military applications. Specifically, the Linear Amplification of Nonlinear Components (LINC) power amplifier presently under use by the Navy is examined. Initial studies by the principal investigator has shown that the combiner design seems to be the source of the inability to simultaneously achieve the linearity and efficiency goals. The project will begin with a simulation study of different combiner topologies and examine design modifications to these topologies, with a goal of establishing an optimization of the linearity/efficiency tradeoff. The second part of the project will involve the construction and microwave testing of a hardware prototype for the combiner. Finally, the results of the first two parts of the work will be used to propose an improved design for the LINC system. The results of this project are expected to lead to a full proposal to the Naval Research Laboratory Radar Division. The topics are in line with NRL Radar Division BAA 53-07-02 as posted on the NRL website.
A Verifiable Composition Approach for Trustworthy System Development(Computer Science / School of Engineering and Computer Science)
The increasingly critical roles that pervasive software systems are playing in society makes clear the need for trustworthy software. Trustworthiness is not a quality that should be tacked onto software; software must be engineered to be trustworthy. Security, fault-tolerance, and other trust properties can affect multiple modules in a design. Ad-hoc approaches to integrating trust properties across modules in a complex design are highly likely to produce faulty designs that lead to security breaches or other costly system failures that adversely affect system trustworthiness.
This research proposes a novel approach to integrating trust properties into software designs. Software trust properties are described in aspects that can be methodically integrated with an application design (referred as a primary model). A design of a trustworthy software system is synthesized by composing aspects and the primary model. During synthesis, conflicts and undesirable emergent properties that can lead to failures that diminish trustworthiness are systematically uncovered and resolved. The approach also provides techniques for rigorously analyzing synthesized designs to determine the level of trustworthiness that can be realized. The research hypothesis is that describing trust properties in aspects significantly eases the tasks of specifying, analyzing, integrating, and evolving the properties for large-scale, complex applications.
The Ontogeny of Aerobic Capacity and Lipid Metabolism in Ice Seals(Biology / College of Arts and Sciences)
Air-breathing diving vertebrates exhibit physiological adaptations in their muscles (and other tissues) that sustain an aerobic, lipid-based metabolism under conditions of hypoxia and ischemia. Smaller phocid species such as bearded, spotted and ribbon seals are less capable divers than larger seal adults, in part because of their higher weight-specific metabolic rate and proportionately smaller blood and muscle oxygen stores. The ontogeny of muscle aerobic capacity, lipid metabolism, and oxygen stores in the skeletal muscles is of overwhelming importance for diving ability, yet we have only recently begun to describe the development of these physiological variables. In the proposed research, I will investigate the ontogeny of muscle adaptations (heart, liver and skeletal muscle) that ultimately determine the diving capabilities of phocid seals along with the role lipids play in these tissues. The ontogenetic development of these adaptations in the muscles of phocid seals will improve our understanding of the physiological mechanisms that protect tissues and organs from hypoxia and ischemic induced injury.
Targeted Measurements to Improve Air Pollution Emission Inventories(Environmental Science / College of Arts and Sciences)
This study will investigate the organic compound emission and trace element emission from known and previously unidentified sources of air pollution in Texas. Most notable this study will measure for the first time the magnitude of emission from oil and natural gas flares. Oil and natural gas flares will be characterized with source identifying elemental and molecular markers. Soil and air samples will be collected in transects around select non-point stationary sources. Samples will be analyzed for organics including polycyclic aromatic hydrocarbons by gas chromatographic mass spectrometry (GC/MS) as well as for trace metals using inductively coupled plasma mass spectroscopy (ICP-MS). Air samples will be collected using high volume air samplers. This study has three objectives: 1) improve our understanding of air quality with respects to non-point stationary sources as well as emissions pseudo-point stationary sources such as oil and natural gas flares 2) reduce unknown variability and irregularity associated with non-point stationary sources emission and 3) characterized emission patterns from such sources. The proposed objectives will be accomplished by measuring organic compound emissions and trace element emission from non-point stationary sources that include the flaring of oil and natural gas using spatial and temporal transects.