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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.
111

Integrating apatite (U-Th)/He and fission track dating for a comprehensive thermochronological analysis: refining the uplift history of the Teton Range

Brown, Summer Jasmine 24 June 2010 (has links)
Uplift of the Teton Range is primarily controlled by displacement across the range-front Teton normal fault. The Tetons comprise the footwall block while the hanging wall encompasses Jackson Hole valley and a portion of the Snake River. Relative to the rest of the Rocky Mountains, the Tetons experienced the majority of uplift very recently, substantiating the need for a detailed investigation integrating structural analysis and bedrock thermochronometry. New low-temperature cooling ages are documented in three vertical transects across the Teton Range and at low elevations parallel to the Teton fault. Samples adjacent to the Teton fault are consistently young (~9 Ma) and represent a minimum estimate for the onset of Teton fault-related uplift. Modeling of time-temperature histories supports a ~9-11 Ma onset of rapid uplift, indicating that the Teton fault likely originated as a Basin and Range-type structure. A maximum throw of ~8 km occurs proximal to the Grand Teton, while the average throw for the entire ~100 km along-strike fault length is ~3.3 km. Thus, the geometry of the Teton fault is comparable to traditional scaling relationships dictating a correlation between fault length and displacement. Inversion of the typical (U-Th)/He (AHe) and fission track (AFT) relationship in a few of the Teton Range samples is a result of intense zoning, primarily in apatite from Precambrian layered gneisses. Nonetheless, both the AHe and AFT ages consistently indicate slight differential uplift of the Tetons between the Late Oligocene and Middle Miocene. HeFTy models indicate that doming of the Precambrian-Paleozoic unconformity occurred prior to ~50 Ma. However, by ~15 Ma, rapid cooling of the Mount Moran section essentially "flattened" the unconformity. Thus, the modern domed shape is a result of displacement across the Teton fault, allowing the unconformity to be used as a proxy for fault deformation. Moreover, reconstruction of the unconformity and volume calculations produced an average depth to incision of ~0.3 km and a long-term erosion rate of 0.18 mm/yr. Compared to the long-term uplift rate of 0.22 mm/yr, this provides a quantitative explanation for the modern Teton topography. / Master of Science
112

Advanced Test Range Verification at RF Without Flights

Williams, Steve 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / Flight and weapons test ranges typically include multiple Telemetry Sites (TM Sites) that receive telemetry from platforms being flown on the range. Received telemetry is processed and forwarded by them to a Range Control Center (RCC) which is responsible for flight safety, and for delivering captured best source telemetry to those responsible for the platform being flown. When range equipment or operations are impaired in their ability to receive telemetry or process it correctly, expensive and/or one-of-a-kind platforms may have to be destroyed in flight to maintain safety margins, resulting in substantial monetary loss, valuable data loss, schedule disruption and potential safety concerns. Less severe telemetry disruptions can also result in missing or garbled telemetry data, negatively impacting platform test, analysis and design modification cycles. This paper provides a high level overview of a physics-compliant Range Test System (RTS) built upon Radio Frequency (RF) Channel Simulator technology. The system is useful in verifying range operation with most range equipment configured to function as in an actual mission. The system generates RF signals with appropriate RF link effects associated with range and range rate between the flight platform and multiple telemetry tracking stations. It also emulates flight and RF characteristics of the platform, to include signal parameters, antenna modeling, body shielding and accurate flight parameters. The system is useful for hardware, software, firmware and process testing, regression testing, and fault detection test, as well as range customer assurance, and range personnel training against nominal and worst-case conditions.
113

Enhanced Flight Termination System Study Overview and Status

Cronk, Steven G., Tobin, Maria A., Sakahara, Robert D. 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Range Commanders Council (RCC) Range Safety Group (RSG) is conducting a study into the next generation of ground-based flight termination technology, known as the Enhanced Flight Termination System (EFTS) study. The study was initiated by the RCC in April 2000 and scheduled to be complete in March 2002. The Government is performing the study with support from contractors and academia. In addition to the RSG, the Telemetry Group, Frequency Management Group, Telecommunications and Timing Group of the RCC support the study. Additionally, the National Security Agency is providing key support along with vendors who design, build, and test range safety systems. This paper will describe the background, goals, and current status of the study.
114

Design Scaling Og Aeroballistic Range Models

Kutluay, Umit 01 December 2004 (has links) (PDF)
The aim of this thesis is to develop a methodology for obtaining an optimum configuration for the aeroballistic range models. In the design of aeroballistic range models, there are mainly three similarity requirements to be matched between the model and the actual munition: external geometry, location of the centre of gravity and the ratio of axial mass moment of inertia to the transverse mass moment of inertia. Furthermore, it is required to have a model with least possible weight, so that the required test velocities can be obtained with minimum chamber pressure and by use of minimum propellant while withstanding the enormous launch accelerations. This defines an optimization problem: to find the optimum model internal configuration and select materials to be used in the model such that the centre of gravity location and the inertia ratio are matched as closely as possible while the model withstands the launch forces and has minimum mass. To solve this problem a design methodology is devised and an optimization code is developed based on this methodology. Length, radius and end location of an optimum cylinder which has to be drilled out from the model are selected as the design variables for the optimization problem. Built&ndash / in functions from the Optimization Toolbox of Matlab&reg / are used in the optimization routine, and also a graphical user interface is designed for easy access to the design variables. The developed code is a very useful tool for the designer, although the results are not meant to be directly applied to the final product, they form the starting points for the detailed design.
115

Tectonic stress regime of the Cascades region and tectonic classification of large calderas

Ferrall, Charles C January 1986 (has links)
Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1986. / Bibliography: leaves 361-395. / Photocopy. / xviii, 395 leaves, bound ill. 29 cm
116

Biomechanical analysis of carpal flexion and extension

Hallbeck, M. Susan 01 February 2006 (has links)
An experiment was performed to evaluate the relations between active range of motion (ROM) and upper limb anthropometric dimensions. Eight anthropometric dimensions, forearm length, distal and proximal forearm circumferences, wrist breadth, wrist thickness, wrist circumference, hand breadth, and hand length in combination with gender, wrist position, and direction of motion or exertion were evaluated to determine their effects on instant center of rotation (ICOR) and the magnitude of force exertion. The knowledge gained from analysis of the study data will be the first step in the formulation of a biomechanical model of wrist flexion and extension. Such a model would predict forces and torques at specific wrist postures and be employed to reduce cumulative trauma disorders of the wrist. Sixty right-hand dominant subjects (30 male, 30 female) between 20 and 30 years of age all reporting no prior wrist injury and good to excellent overall physical condition, were employed in this study. The upper limb anthropometric dimensions and ROM were measured and recorded for each subject. The anthropometric dimensions were compared to tabulated data. The measured active ROM values were compared with values in the literature. Correlation coefficients between pairs of anthropometric variables (by gender) were calculated. The mean active ROM measures, 164.0 deg for females and 151.8 deg for males, were significantly different (<i>Z</i> = 2.193, <i>p</i> = 0.014). The relationships between the anthropometric variables and active ROM were analyzed by three methods: correlation between ROM and each anthropometric dimension, prediction (regression) equations, and analysis of variance (ANOVA). No correlation coefficient between ROM and any anthropometric dimension was greater than 0.7. No prediction equation, based upon linear and quadratic combinations of anthropometric dimensions variables, was above the threshold of acceptability (<i>R²</i> ≥ 0.5). The results of the ANOVA showed a significant effect for gender. The ICOR had been hypothesized to be either in the head or neck of the capitate. The Method of Reuleaux was employed to locate the leOR points for flexion and extension (over the ROM) of the wrist with three load conditions, i.e., no-load, palmar resistance, and dorsal resistance. Analysis of the data, using ANOYA, showed that wrist position was the only significant variable. Thus, in future wrist models, the assumption cannot be made that the wrist is a pin-centered joint for flexion and extension. The static maximal voluntary contractile forces that can be generated by recruiting only the six wrist-dedicated muscles in various wrist positions were measured. There was a significant gender difference for the mean flexion force (<i>Z</i> = 4.00, <i>p</i> = 0.0001) and for the mean extension force (<i>Z</i> = 4.58, <i>p</i> = 0.0001). Females averaged 76.3 percent of the mean male flexion force and 72.4 percent for extension. The force data, categorized by gender, were then analyzed using three methods: correlation of variable pairs, regression equations, and ANOVA. None of the eight anthropometric dimensions and ROM was correlated with flexion or with extension force at an acceptable level. The prediction equations, linear and quadratic combinations of all possible subsets of anthropometric dimension values, ROM, and wrist position did not meet the minimum acceptable level of <i>R²</i> ≥ 0.5. The ANOVA procedure showed gender, wrist position, direction of force exertion, and the wrist position interaction with direction to have significant effects upon maximal force exertion. / Ph. D.
117

Comparison of See-and-Avoid Performance in Manned and Remotely Piloted Aircraft

Kephart, Ryan J. 29 December 2008 (has links)
No description available.
118

Image-Based Passive Acquisition of Range Data

Xu, Shi January 1992 (has links)
An image-based technique for passive acquisition of three-dimensional (3-D) range data is proposed. The distance is extracted, in this technique, from the estimation of focus conditions on images produced through a monocular imaging system under natural illumination. The image taken from a 3-D object is generally out-of-focus (defocused). For each surface point, the severity of defocus on the image depends upon how far away the point is from the imaging system and how camera (optical) parameters are adjusted. Each setting of the parameters can be recorded physically, and associated in object-space with the inverse of a distance that corresponds to the position for the sharpest imaging under this setting. Therefore, for a given surface point the defocus severity is a function of such an inverse object-distance. It can be shown that this function is symmetrical to, and monotonic on both sides of, a point corresponding to the inverse distance of the surface point. To estimate the parameters of the function (one of which is the inverse distance of the surface point), 3~4 images need to be taken under different camera settings with known associated inverse distances in object-space, determined through a once-for-all calibration procedure. Defocus severity is evaluated from a calculation on the window image that corresponds to a small area around the surface point, and the inverse variance in the window is suggested in this technique for the best performance. The 3-D surface geometry is acquired by applying the algorithm, in parallel, to all surface points in the field of view. Various aspects of the technique are discussed and several algorithms are developed. The technique is implemented on an opto-digital imaging system and evaluated under different conditions. A number of objects are tested to demonstrate its performance. / Thesis / Master of Engineering (ME)
119

Cattle grazing behavior and range plant dynamics in southern Arizona.

Gamougoun, Ngartoina Dedjir. January 1987 (has links)
A 15-month study was conducted on the Santa Rita Experimental Range to evaluate the factors influencing both plants and cattle in southern Arizona. Forage biomass, nutrient value, botanical composition, and ground cover were greater in the growing season than in the dormant season. Moderate and heavy pastures had lower plant parameters than very heavy pasture, except for forage biomass and Lehmann lovegrass proportion, forage fiber and ground cover. Slopes and washes had a higher forage nutrient content and lower biomass and ground cover than the uplands. Lehmann lovegrass was more abundant on the uplands and in the washes than on the slopes and the reverse was true for native grasses and shrubs. Understory forages contained greater nutrients and forbs than open forages and the opposite occurred for shrubs and ground cover. Grazing activities, drinking, salting, defecation, urination and rumination were greater in the growing seasons, but standing and idling were greater in winter. There were no differences among pastures in major activities, but walking, drinking and salting were greater on very heavy pasture than on moderate and heavy pastures. Most grazing activities were on the uplands and resting activities were in the washes. Biting rates were similar among topographic areas. Upland and wash defecation and urination frequencies were similar and higher than slope frequencies. Grazing activities were greater in the open than under canopy and the reverse was true for resting activities. Open and canopy areas were similar in defecation and urination frequencies and biting rates. Except for resting activities, major and minor activities were more intense in the afternoon than in the morning. Morning and afternoon biting rates were similar. The weather index was the most important predictor of all cattle activities, except for the defecation frequency which mostly depended on the proportion of green forage. The forage nutrients and green proportion were the second and third important predictors of cattle activities, respectively. In conclusion, plants and animals interact and both react to environmental conditions. The recommendations for best management of a grazing land ecosystem should consider these conditions.
120

Twenty-five years of grazing research at Meadow Creek in the Starkey Experimental Forest and Range

Walburger, Kenric 18 January 2002 (has links)
Graduation date: 2002

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