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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.
281

RANGE SAFETY CASE STUDY: WESTERN RANGE CENTRALIZED TELEMETRY PROCESSING SYSTEM (WR CTPS), A LARGE DISTRIBUTED GROUND SYSTEM

Mather, Jonathan, Shaw, Nancy 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper presents a case study of the Western Range Centralized Telemetry Processing Subsystem (WR CTPS). This system was developed by Lockheed Martin Integrated Systems and Global Services and L-3 Communications Telemetry-West as part of the Range Standardization and Automation (RSA) IIA program. Requirements included real-time simultaneous acquisition of 16 PCM streams at rates of up to 30M bits per second; real-time processing; and data display on workstations connected over a gigabit Ethernet network. This system is designed for range safety and needs to be fault-tolerant while maintaining 100 percent data availability in the event of a single failure during an operation. The development of such a system demanded a rigorous Systems Engineering approach to ensure the successful upgrade and deployment onto the range infrastructure. This case study provides an overview of the system technical requirements and its architecture. The summary presents challenges encountered during the development and lessons learned while meeting them.
282

GROUND SUPPORT FOR THE SPACE-BASED RANGE FLIGHT DEMONSTRATION 2

Burkes, Darryl A. 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The primary objective of the NASA Space-Based Range Demonstration and Certification program was to develop and demonstrate space-based range capabilities. The Flight Demonstration 2 flights at NASA Dryden Flight Research Center were conducted to support Range Safety (commanding and position reporting) and high-rate (5 Mbps) Range User (video and data) requirements. Required ground support infrastructure included a flight termination system computer, the ground-data distribution network to send range safety commands and receive range safety and range user telemetry data and video, and the ground processing systems at the Dryden Mission Control Center to process range safety and range user telemetry data and video.
283

EXTENDED RANGE COMMUNICATIONS SUPPORT FOR THE X-33

Eslinger, Brian, Garza, Reynaldo 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / Communications support for the X-33 requires addressing several unique challenges to meet program and range safety requirements. As an avenue to minimize costs, the program has reduced requirements to the communications system, which lowered the cost of networking the extended range. Cost trade-offs showed that by lowering the telemetry data rate from 2 Megabits per second to 1.440 Megabits per second that significant cost avoidance could be realized. Also, by adopting standard telecommunications data rate for the uplink data stream, an efficient and integrated solution for the extended range communications could be supported. Meeting the program requirements as well as range safety requirements for this effort are critical to the success of the program. This paper describes some of the important requirements driving the design of the extended range communications support and the design of the system to meet those requirements.
284

AN INTEGRATED APPROACH TO ROBUST FLIGHT TERMINATION FOR SMALL MISSILE TEST AND TRAINING RANGE USE

Alves, Daniel F. Jr 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / This paper will investigate the areas that must be addressed to implement a truly integrated Range instrumentation system on a GPS-based Range, using a patented L-Band commanding scheme. Hardware issues will be highlighted as well the issues to be addressed in changing from an audio tone-frequency modulated command system to a digital system incorporating encryption and spread spectrum. Some thoughts addressing costs and schedule to incorporate this approach into the architecture of Joint Advanced Missile Instrumentation (JAMI) program are also presented, as well as a discussion of the benefits to be accrued over the existing system.
285

NAVSTAR-GLOBAL POSITIONING SYSTEM (GPS) FOR RANGE APPLICATIONS

HANCOCK, THOMAS P 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1985 / Riviera Hotel, Las Vegas, Nevada / The purpose of this paper is to describe the Tri-Service effort to use the NAVSTAR Global Positioning System (GPS) on Tri-Service ranges. It will describe the background, the development program, the equipment, the management team, the specifications that the equipment must satisfy, the integration into five DOD ranges, an assessment of developmental risk, a recap of logistical aspects, and will provide a development schedule.
286

DEMONSTRATION OF A LOW-COST MOBILE LAUNCH RANGE SAFETY SYSTEM

Huff, Dave, Rice, Robert 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Ballistic Missile Range Safety Technology (BMRST) program developed and demonstrated a low-cost, rapidly reconfigurable, launch range tracking and safety system. The system is comprised of both an on-board tracking unit and a ground based telemetry acquisition and control system. The on-board unit is based on an integrated GPS/INS unit with an embedded S-band telemetry transmitter. The ground system is comprised of fully redundant telemetry acquisition systems, telemetry processing computers, tracking computers, and secure/IRIG UHF command destruct transmission systems. This paper provides an overview of the system architecture and describes telemetry system design trades in particular. The paper describes how aircraft and satellite testing supports verification of system tracking capability. The paper closes by presenting data from the Quick Reaction Launch Vehicle (QRLV) flight test in Kodiak, Alaska.
287

Late Eocene paleoaltitude, paleoclimate, and paleogeography of the Front Range region, Colorado.

Gregory, Kathryn Mary. January 1992 (has links)
Erosion beveled the Laramide Front Range uplift in Colorado to a surface of low relief by the end of the Eocene. This study uses paleobotanic climate analysis techniques to determine the paleoelevation of this regional surface by examining the overlying 34.9 Ma Florissant flora. Multiple regression models explaining 93.4% of the variance in mean annual temperature (MAT), 86.1% of the variance in growing season precipitation (GSP) and 65.7% of the variance in rainfall distribution were derived from J. A. Wolfe's dataset of 31 leaf physiognomic character states from 86 modern vegetation sites. When applied to a new collection of 29 species from the Florissant flora, estimates of MAT = 10.7 ± 1.5°C, and GSP = 55.6 ± 12.5 cm, with precipitation occurring mostly during the growing season, are derived. This paleoclimate estimate is corroborated by data from late Eocene Sequoia affinis from Florissant. Higher mean ring width of the fossil trees as compared to modern counterparts can be explained by a climate with summer mean monthly temperatures ≥ 14°C and summer mean monthly rainfall >1.5 cm. The estimated MAT, when combined with coeval sea level MAT and terrestrial lapse rate, implies an elevation of 2.3-3.3 km for Florissant, which is indistinguishable from the modern elevation of 2.5 km. The elevation of Florissant is tied to that of the Great Plains by the Wall Mountain Tuff, so the Great Plains were also high. The elevation was created either by underplating and/or mass transfer in the Laramide, or by mantle uplift of crust thickened by pre-Laramide tectonics. This elevation estimate implies that: (1) Pliocene uplift is not required to explain the present elevation. Thus, late Tertiary plateau uplift in the western US was not a contributing factor to the marked global cooling since 15 Ma; and (2) in the late Eocene, regional surfaces of planation could be formed at elevations significantly above sea level but below tree line. The surface was possibly formed from a lack of storminess; a preponderance of small storm events will diffusively smooth topography.
288

SLOPE AND EXPOSURE EFFECTS ON RANGE SITE INTERPRETATIONS (ARIZONA).

MEYER, WILLIAM WALTER. January 1983 (has links)
Vegetational responses to changes in exposures within a constant slope range were studied on the Shallow Upland Range Sites and Granitic Hills Range Site in the Chihuahuan semidesert grasslands in Central Arizona. Sixteen exposures with slopes between 11 and 17 degrees were chosen for subsample sites. Environmental, complete soil descriptions, and vegetational composition data were taken. All data were analyzed using analyses of variance, ordination programs, and regression analyses to determine climate, soils, and vegetational relationships among exposures. The resulting data indicated that the geological lithologic unit on which the soils formed was the most important factor affecting apparent vegetational type. In this study, the data obtained from the complete soil profile descriptions contributed little information to the understanding of vegetational responses. Soil surface characteristics and surface soil horizon properties influenced soil moisture relationships. The conservation of soil moisture appeared to be more important to plant communities than did the total moisture holding capacity of the soil continuum. Monthly precipitation reliability and soil surface reflectances were environmental factors affecting plant communities occurring on different exposures. Fall/spring, winter/spring, and spring soil temperature interactions were the most important environmental factors affecting vegetation on different sloping exposures. All exposures within each of the four sample locations had vegetational components that were similar to the vegetational components of other exposures but all exposures were found to have different plant communities. Each exposure within a given slope range is a phase and/or subphase of currently used range site descriptions. A range site that is based on a potential natural community at one type location cannot be extrapolated across broad geographical expanses to define vegetative potentials for other areas having similar vegetative aspects. Range site descriptions must be site specific for one geographical rangeland that has had the same historical uses.
289

Geographic Range Size: Measuring The Fundamental Unit Of Biogeography and Evaluating Climatic Factors That May Influence Longitudinal Range Size Gradients In North American Trees

Donoghue, John, Donoghue, John January 2016 (has links)
This research seeks to advance our understanding of how to make better informed species conservation decisions on a global scale and advance our understanding of how species' spatial distributions (their geographic ranges) may be respond to climate change, so we can know which areas should be set aside to ensure their present and future conservation. To understand how species' geographic ranges may change, it's important to first assess how geographic ranges are defined and measured. The quantifiable measurement of a species' geographic range, (its geographic range size), is a key criterion the International Union for the Conservation of Nature uses to determine the conservation status and prioritization of species worldwide. Thus, part one of this thesis evaluates different measures for how geographic range size is commonly quantified in the conservation community, to determine whether some range size measures are more reliable than others.Further, to evaluate how species' geographic ranges may respond to climate change, I examine the climatic factors influencing observable longitudinal range size gradients in the North American tree species range maps from E.L. Little's Atlas of North American Trees.
290

A Study of the Relationship between the Intensity of Short-Range and Medium-Range Capacity Management and the Effectivenesss of Manufacturing Operations

Yehudai, Joseph 05 1900 (has links)
The objective of this study was to examine the relationship between intensity of short-range and medium-range capacity management and effectiveness of manufacturing operations. Data were collected to test the null hypothesis which stated that intensity of short-range and medium-range capacity management does not influence manufacturing effectiveness. Intensity of short-range and medium-range capacity management was indicated by the following variables: (1) production standards; (2) priority determination; (3) delivery dates determination; (4) material requirements planning; (5) routing information; (6) capacity utilization; and (7) backlog measurement. Manufacturing effectiveness was indicated by the following variables: (1) delivery dates performance; (2) lead times; (3) subcontract work; (4) direct labor overtime; (5) direct labor efficiency; (6) plant and equipment utilization; and (7) work in process inventory. The population selected to provide data for this study is the manufacturing firms in the State of Texas with five hundred or more employees. Over 42 percent of the eligible firms responded to a six-page questionnaire. Several multivariate techniques were utilized for data analysis: (1) factor analysis; (2) canonical correlation analysis; (3) bivariate correlation; (4) multiple linear regression; (5) cross-tabulation; and (6) analysis of variance. The results of this research did not adequately support the rejection of the null hypothesis. However, they did definitely identify a distinct group of capacity management intensity variables that influence manufacturing effectiveness in specific cases. Intensity variables were placed in three groups that identified how influential they were over the effectiveness measures. The most influential group included the variables: production standards and material requirements planning. The indication for the manufacturing manager is to concentrate on improvements in these areas. Effectiveness variables were also placed in three groups that identified the level at which the variables were influenced by the intensity variables. The highly influenced group included plant and equipment utilization and delivery dates performance.

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