This thesis presents the design of a Sensor Control Chip (SCC) developed to provide the required clock and bias signals for the Large Synoptic Survey Telescope’s CCD imagers. The circuit consists of current-summing DACs followed by trans-impedance operational amplifiers to control the rail voltages of the clock signals and bias voltages. The clocks are input to the SCC through LVDS receivers and converted internally to the required amplitude for driving the CCDs. The ASIC is designed to drive clock signals with 20-V adjustable output voltage swing and a maximum output current of 150 mA. The prototype chip has been fabricated in a 0.8-um BCD-SOI process, and is designed to operate down to 175K. Design techniques used in the ASIC will be presented, along with room temperature and operational temperature test results obtained from prototype chips. Test results have shown that the prototype chip is fully functional and agrees well with simulation results.

Hydrologic processes impact the functioning of aquatic ecosystems and influence fish population dynamics. The flow regime of a stream affects the structure, composition, and productivity of fish communities by regulating abiotic habitat conditions and biotic community processes. In the Great Smoky Mountains National Park (GRSM), native brook trout (Salvelinus fontinalis) populations have declined in some watersheds over the past decade, believed to be primarily due to episodic acidification. The potential affects long-term hydrologic patterns, temporal hydrologic trends, and hydrologic extremes have on brook and rainbow trout (Oncorhynchus mykiss) populations were explored in this study. The current GRSM fish sampling program began nearly two decades ago; a total of 69 streams, including 369 sites, are routinely sampled by GRSM fisheries biologists with standard methods. Detailed data is collected on the trout populations. The Nature Conservancy¡¯s Indicators of Hydrologic Alteration (IHA) was used to quantify the flow regime of each stream into 67 ecological relevant parameters. Because the trout sites were located in remote ungaged streams, the Hydrologic Simulation Program FORTRAN (HSPF) was used to simulate flows at each trout site for a study period lasting 18 years (1990-2007). Using local climate data the model was calibrated by adjusting parameters including storage, infiltration, runoff, and ground water for three elevation classes (low < 800 m ¡Ü middle ¡Ü 1,200 m < high) to observed stream flows from two USGS gaging stations and one NPS gaging station. The parameters defined by IHA included the a) magnitude, b) frequency, c) duration, d) time, and e) rate of change of hydrological events. IHAs were statistically compared to the surveyed trout populations. Results indicated the abundance of young-of-the-year (YOY) brook and rainbow trout significantly declined after extreme floods and droughts. In particular, low-flows during droughts significantly reduced recruitment for both brook and rainbow trout, which is likely due to decreased spawning habitat. Brook trout populations in larger low-elevation streams showed more stability compared to smaller headwater streams. The study provided GRSM resource managers a calibrated hydrology model with unique flow parameters characterizing GRSM watersheds, and possible influences hydrologic conditions may have on trout populations.

The objective of the present study was to laser process a refractory metal – refractory carbide alloy based on W-Ti-C ternary system for severe service applications. The key concept was to cast a eutectic alloy of tungsten and titanium carbide/carbonitride straight from the melt through laser materials processing route. In the present study, a WTi- C ternary alloy has been laser processed into three-dimensional objects and surface protective coatings. Two novel fabrication systems were designed to build threedimensional objects, namely tower nozzle solid freeform fabrication system and axissymmetric laser powder deposition system. W-Ti-C alloy based protective coatings were deposited on graphite substrates, through laser melting of pre-placed powder mixture, to widen the use of carbon structural elements for high temperature applications. A method for depositing W-Ti-C alloy on steel using multi-intermediate layers strategy is discussed and the preliminary results are presented in this study.

Precision op amps are widely used in instrumentation, automotive, and industrial applications. This thesis presents the design and characterization of a low-power precision operational amplifier that uses “ping-pong” autozero architecture for automatic offset correction. The op amp is designed for extreme environment applications, operating across a wide temperature range (minus 180 degree Celsius to plus 120 degree Celsius) with low offset, low drift and low power consumption. This design has been fabricated in a SiGe BiCMOS 0.5-micron process and the measured results demonstrate that the op amp is fully functional and achieves less than 40 microvolt input-referred offset voltage with 0.1 microvolt per degree offset voltage drift and 1 microwatt power consumption.

OBJECTIVE: The objective of this experimental investigation was to document the turbulent mixing of subsonic axisymmetric hydrogen and air streams at velocity ratios which have not been previously reported. Special emphasis is placed on [1] determining the effect of velocity ratio and density gradients on the centerline decay of composition, velocity, and total enthalpy, and on the composition, velocity, and total enthalpy profile shapes, and [2] presenting nondimensional composition, velocity, and total enthalpy relationships which are indicative of the turbulent Prandtl, Lewis, and Schmidt numbers.

Years of study and constant anecdotal infonnation dating back to the ancient Romans exists regarding the relationship of mandibular position, occlusion surface changes, and human performance. Such old sayings and practices like "bite the bullet" and the actual act ofclenching one's teeth on a stick prior to exertion or in anticipation ofpain are but two examples of how this relationship has been intuitively understood by man for some time. Previous scientific works in this area have generally suffered at least one serious shortcoming in data collection, data analysis, test device flaws or lack of control measures. There seem to be emotionally charged efforts to either prove or disprove the apparent relationship between jaw positioning and human performance. It is unclear why there has been so much controversy but the fact that this emotional side taking exists leads to concerns about preconceptions on the part ofthe previous research teams. In an effort to reach some realistic levels of confidence, this effort has been accomplished in a double blind, placebo controlled, unbiased manner utilizing the tenets of the scientific method throughout. The data indicate that a self-fit, intra-oral device is beneficial in improving grip strength values for both men and women at a confidence level of at least 95 percent. In addition, there is a 96 percent confidence level that a mandibular repositioning appliance is of greater assistance in grip strength tests than a placebo device. Therefore, the results of this research initiative demonstrate that statistically relevant human performance increases are possible by employing a self-fit, intra-oral device in active men and women ofall ages.

Thesis (M.App.Sc.) - Carleton University, 2009. / Includes bibliographical references (p.136-143). Also available in electronic format on the Internet.

Thesis--PlanA (M.S.)--University of Wisconsin--Stout, 2004. / Includes bibliographical references.

Thesis (M.S.)--Ohio State University, 1955. / Includes bibliographical references (leaf 48). Available online via OhioLINK's ETD Center

This thesis describes a novel procedure for achieving full 3D reconstruction from multiple RGB-D cameras configured such that the amount of overlap between views is low. Overlap is used to describe the portion of a scene that is common in a pair of views, and is considered low when at most 50% of the scene is common. Compatible systems are configured such that interpreting cameras as nodes and overlap as edges, a connected undirected graph can be constructed. The fundamental goal of the proposed procedure is to calibrate a given system of cameras. Calibration is the process of finding the transformation from each camera's point of view to the reconstructed scenes global coordinate system. The procedure focuses on maintaing the accuracy of reconstruction once the system is calibrated.par RGB-D cameras gained popularity from their ability to generate dense 3D images; however, individually these cameras can not provide full 3D images because of factors like occlusions from and a limited field of view. In order to successfully combine views there must exist common features that can be matched or prior heuristics pertaining to the environment that can be used to infer alignment. Intuitively, corresponding features exist in overlapping regions of views. Combining data from pairs of overlapping views would provide a more full 3D reconstructed scene. A calibrated system of cameras is susceptible to misalignment. Re-calibration of the entire system is expensive, and is unnecessary if only a small number of cameras became misaligned. Correcting misalignment is a much more practical approach for maintaing calibration accuracy over extended periods of time. par The presented procedure begins by identifying the necessary overlapping pairs of cameras for calibration. These pairs form a spanning tree in which overlap is maximized; this tree is referred to as the alignment tree. Each pair is aligned by a two-phase procedure that transforms the data from the coordinate system of the camera at a lower level in the alignment tree to that of the higher. The transformation between each pair is catalogued and used to reconstruction of incoming frames from the cameras. Once calibrated, cameras are assumed to be independent and their successive frames are compared to detect motion. The catalogued transformations are updated on instances that motion is detected essentially correcting misalignment. \par At the end of the calibration process the reconstructed scene generated from the combined data would contain relative alignment accuracy throughout all regions. Using this proposed algorithm reconstruction accuracy of over 90% was achieved for systems calibrated with the angle between the cameras 45 degrees or more. Once calibrated the cameras can observe and reconstruct a scene on every frame. This is reliant on the assumption that the cameras will be fixed; however, in a practical sense this cannot be guaranteed. Systems maintained over 90% reconstruction accuracy during operation with induced misalignment. This procedure also maintained the reconstruction accuracy from calibration during execution for up to an hour. The fundamental contribution of this work is the novel concept of using overlap as a means of expressing how a group of cameras are connected. Building a spanning tree representation of the given system of cameras provides a useful structure for uniquely expressing the relationship between the cameras. A calibration procedure that is effective with low overlapping views is also contributed. The final contribution is a procedure to maintain reconstruction accuracy overtime in a mostly static environment.