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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.
51

Genetic Characterization of Intermixed Walleye Stocks in Claytor Lake and the Upper New River, Virginia

Palmer, George Caleb 15 December 1999 (has links)
Historically, the New River may have contained a genetically unique, river-spawning population of walleye (Stizostedion vitreum). Additionally, a number of genetically different walleye stocks have been stocked in Claytor Lake, Virginia. The increasing importance of the walleye fishery led to interest in clarifying key unknowns regarding the biology of the New River walleye stock. A radio telemetry study and genetic evaluation of present-day stocks led to identification of three spawning areas and the characterization of the genetic stock structure of walleye in Claytor Lake and the upper New River. Using radio telemetry to track movements of walleye, I determined that two resident walleye populations co-exist: one within Claytor Lake and the other in the New River above the lake. These populations establish spatially disjunct home ranges, remaining spatially separated throughout most of the year. Although there is no blockage to movement or migration, walleye within Claytor Lake generally spawn at Allisonia, while walleye within the upper New River spawn at Buck Dam. Some walleye from both populations spawn in other areas, such as Fosters Falls. Using allozymes, microsatellite DNA, and mitochondrial DNA marker techniques to examine population structure of walleye, I determined that the walleye within Claytor Lake are a panmictic population. This is the result of years of stocking walleye from different genetic stocks and interbreeding among individuals. The genetic structure of walleye from the New River also shows the presence of more than one genetic stock. Within the New River population, there exists a genetic stock of walleye that is characterized by three mitochondrial DNA haplotypes (43, 44, and 45) that previously have not been seen. This may be indicative of a unique walleye stock that is native to the New River and which has remained spatially or temporally segregated by spawning habits. The co-existence of two different walleye populations in the Claytor Lake / upper New River system justifies different management strategies. I recommend that management of the walleye population in Claytor Lake focus on increasing the exploitation of this non-indigenous stock. Management of the upper New River walleye population should focus on conservation of the unique native stock through supportive breeding and/or strict harvest regulations. / Master of Science
52

THE BASE STATION TELEMETRY DATA PROCESSING SYSTEM FOR UNMANNED HELICOPTERS

Bin, Xu, XiaoLin, Zhang, Guolei, Lu, Weiwei, Hu 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / This paper discusses the design and implementation of the base station telemetry data processing system for the unmanned helicopter. The system designed is composed of code synchronizer, decoding and frame synchronizer as well as PCI bus interface. The functions of the system are implemented with very large integrated circuits and a standard PCI inserted card that is compact and easy to install. The result of flight performance tests shows that the system is reliable and can satisfy the requirements of telemetry system for unmanned helicopters.
53

MERGING TELEMETRY DATA FROM MULTIPLE RECEIVERS

Wilson, Michael J. 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Multiple receiver telemetry systems are common in the aeroballistics test and evaluation community. These systems typically record telemetry data independently, requiring post-flight data processing to produce the most accurate combination of the available data. This paper addresses the issues of time synchronization between multiple data sources and determination of the best choice for each data word. Additional filtering is also developed for the case when all available data are corrupted. The performance of the proposed algorithms is presented.
54

ADVANCED RANGE TELEMETRY DYNAMIC MEASUREMENT LISTS

Luten, Robert H., Diekmann, Vernon 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A typical telemetry system for aircraft flight-testing transmits one or several data streams to the ground for real-time display and analysis, and also records the same stream onboard for later playback. During test operations, only a fraction of the available data is used at any given time for real-time display or analysis. More efficient use of the RF channel could be realized if only the data needed for the current test point is transmitted, rather than the entirety of the data. Intelligent selection of a subset of the data stream can provide large reductions in the required telemetry downlink bandwidth. As one of the Advanced Range Telemetry (ARTM) On-Board Data Management (OBDM) initiatives, a prototype on-board data selection subsystem is being developed and demonstrated. The demonstration utilizes COTS telemetry workstations to the maximum extent possible and includes “plug-in” data requestor, selection, and server components to implement the added DML functionality. A significant objective of the OBDM/DML project will be to validate RF channel models to help minimize the amount of flight-testing necessary to validate the DML concept. This paper will discuss the OBDM/DML architecture, integration of several custom components with the COTS portions of the ARTM “test bench”, and the current status of the OBDM/DML development and test program.
55

A COMPACT, LIGHTWEIGHT, LOW POWER, MULTI-FUNCTION TELEMETRY RECEIVER/COMBINER SYSTEM PROVIDES "HANDS OFF" AUTOMATION FOR SYSTEMS COST REDUCTION

O'Cull, Douglas C. 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / With the increased concerns for reducing cost and improving reliability in today's telemetry systems, many users are employing simulation and automation to guarantee reliable telemetry systems operation. This places an increased demand on the remote capabilities of the equipment used in the telemetry system. Furthermore, emphasis has been placed on the ability to decrease the space and power consumption of the telemetry system to facilitate transportability of the a single telemetry system to multiple sites. Finally, today's telemetry systems demand that all equipment provide multiple functions to provide the maximum performance for the lowest system cost.
56

APPLICATION OF DATA COMPRESSION TO FRAME AND PACKET TELEMETRY

Horan, Stephen, Horan, Sheila B. 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Reduction of signal transmission is of paramount concern to many in the telemetry and wireless industry. One technique that is available is the compression of the data before transmission. With telemetry type data, there are many approaches that can be used to achieve compression. Data compression of the Advanced Range Telemetry (ARTM) PCM data sets in the frame and packet modes, and for the entire data file will be considered and compared. The technique of differencing data will also be applied to the data files by subtracting the previous major frame and then applying compression techniques. It will be demonstrated that telemetry compression is a viable option to reduce the amount of data to be transmitted, and hence the bandwidth. However, this compression produces variable-length data segments with implications for real-time data synchronization.
57

FIBEROPTIC TRANSMISSION SYSTEM FOR IMPROVING RAMP TM RECEPTION

Maurer, Ricky L. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The requirement for improved ramp telemetry data and video coverage has prompted the Telemetry Branch at the Naval Air Warfare Center Aircraft Division (NAWCAD) to install an L and S-Band Fiberoptic Transmission System linking multiple hangar locations to the Telemetry Data Center. This system uses Commercial-off-the-Shelf (COTS) equipment and is capable of transmitting analog telemetry data and video from multiple sites to one location for processing and display. The system at NAWCAD has been in use since 1996 and is continually growing to accommodate additional requirements.
58

COMMERCIAL-OFF-THE-SHELF TELEMETRY FRONT-END PROTOTYPING

Hogie, Keith, Weekley, Jim, Jacobsohn, Jeremy 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / The world of data communication and networking has grown rapidly over the last decade, and this growth has been accompanied by the development of standards that reflect and facilitate the need for commercial products that work together in a reliable, robust, and coherent fashion. To a great extent this commercialization, with its increasing performance and diminishing cost, has not been adapted to the data communication needs of satellites. As budgets and mission development and deployment timelines shrink, space exploration and science will require the development of standards and the use of increasing amounts of off-the-shelf hardware and software for integrated satellite ground systems. The Renaissance project at NASA/Goddard Space Flight Center has engaged in rapid prototyping of ground systems using off-the-shelf hardware and software products to identify ways of implementing satellite ground systems "faster, better, cheaper". This paper presents various aspects of these activities, including issues related to the configuration and integration of current off-the-shelf products using telemetry databases for existing spacecraft, an analysis of issues related to the development of standard products for satellite communication, tradeoffs between hardware and software approaches to performing telemetry front-end processing functions, and proposals for future standards and development.
59

SUBMINIATURE TELEMETRY FOR MULTIPLE MUNITION (TECHNOLOGY TRANSITION)

Cullen J. M., Keller, Ed 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / The Instrumentation Technology Branch of Wright Laboratory Armament Directorate (WL/MNSI), has successfully completed an Exploratory Development (6.2) program to develop Subminiature Telemetry (SMT). SMT is a flexible, programmable telemeter with self calibration, power control and Direct Sequence Spread Spectrum modulation. The development program successfully demonstrated the ability of the SMT system to collect up to 64 analog and/or 128 digital discrete signals with programmable gain, bandwidth and offset. The program demonstrated a spread spectrum multiple-access technique that allows for simultaneous transmission and receipt of up to 96 different telemetry units within a 100 MHz telemetry band. WL/MNSI is conducting an Advanced Technology Development (6.3) program to continue development in this area. An air-worthy 4 channel spread spectrum demodulator was developed to support the SMT program but it is too costly for ground applications. The goals of this effort are to reduce the demodulator cost by a factor of 10 while increasing the capability for simultaneously processing data from 24 telemetry units and to support the first Technology Transition Plan (TTP) between WL/MN and the Air Force Development Test Center (AFDTC). The TTP will facilitate the transition of SMT spread spectrum technology to AFDTC for mission support over the next three years.
60

A modular Network Architecture for Lower Cost, High Performance Telemetry Processing

Schumacher, Gary A. 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / There is a continuing need in the aerospace industry for lower cost and more maintainable telemetry data processing systems that can deliver a high level of performance. While systems based on the Intel family of x86 processors and Microsoft operating systems have seen increasing use in lower performance and portable applications, UNIX/VME based systems have been necessary to achieve required performance in higher end, multi-stream applications. Recent developments in the computer industry now promise lower cost alternative to these systems. With currently available technology, it is now possible to provide a powerful distributed processor architecture based entirely on commercial products. The system takes advantage of the latest of Intel Pentium processors, the PCI bus, 100BaseT Fast Ethernet, Microsoft Windows NT, ActiveX technology and NT servers. The architecture offers both current and future cost advantages for test facilities which must support a diverse set of requirements and which must maintain and support systems for many years.

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