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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.
891

THE PEOPLE OF STONE: A STUDY OF THE BASALT GROUND STONE INDUSTRY AT TRES ZAPOTES AND ITS ROLE IN THE EVOLUTION OF OLMEC AND EPI-OLMEC POLITICAL-ECONOMIC SYSTEMS

Jaime-Riveron, Olaf 01 January 2016 (has links)
This dissertation analyzes the basalt ground stone industry at the archaeological site of Tres Zapotes, Mexico. Artifacts and by-products were recovered in the excavations conducted by a University of Kentucky project directed by Christopher Pool. All contexts were examined, and the corpus of this study comprises the whole sequence of production, use, and discards of basalt such as by-products of manufacture, unfinished and finished tools, and discarded artifacts. In this opportunity was possible to study over time a change from the Early/Middle Formative period (Olmec occupation) a centralized and exclusionary political economic system to the Late/Terminal Formative period (Epi-Olmec occupation) when there was a corporate system. This work applied contemporary concepts in social sciences such as agency, practice theory, technological choice, and chaîne opératoire. The variation of raw materials over time was studied recoding physical characteristics and a sample of artifacts was analyzed with X-ray florescence in order to see variation in acquisition of rocks over time.
892

Bridging The Gap Between Telemetry and the PC

Nelson, Wade, Shurtleff, Diana 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1988 / Riviera Hotel, Las Vegas, Nevada / The explosive use and extensive development of software and hardware for the IBM PC and PC Clones over the past few years has positioned the PC as one of many viable alternatives to system designers configuring systems for both data acquisition and data analysis. Hardware abounds for capturing signals to be digitized and analyzed by software developed for the PC. Communication software has improved to where system developers can easily link instrumentation devices together to form integrated test environments for analyzing and displaying data. Telemetry systems, notable those developed for lab calibration and ground station environments, are one of many applications which can profit from the rapid development of data acquisition techniques for the PC. Recently developed for the ADS100A telemetry processor is a data acquisition module which allows the system to be linked into the PC world. The MUX-I/O module was designed to allow the PC access to telemetry data acquired through the ADS 100A, as well as provide a method by which data can be input into the telemetry environment from a host PC or equivalent RS-232 or GPIB interface. Signals captured and digitized by the ADS100A can be passed on to the PC for further processing and/or report generation. Providing interfaces of this form to the PC greatly enhances the functionality and scope of the abilities already provided by the ADS100A as one of the major front-end processors used in telemetry processing today. The MUX-I/O module helps "bridge the gap" between telemetry and the PC in an ever increasing demand for improving the quantity and quality of processing power required by today's telemetry environment. This paper focuses on two distinct topics, how to transfer data to and from the PC and what off-the-shelf software is available to provide communication links and analysis of incoming data. Major areas of discussion will include software protocols, pre vs post processing, static vs dynamic processing environments, and discussion of the major data analysis and acquisition packages available for the PC today, such as DaDisp and Lotus Measure, which aid the system designer in analyzing and displaying telemetry data. Novel applications of the telemetry to PC link will be discussed.
893

The population ecology of certain carabid beetles living in marshes and near fresh water

Murdoch, William January 1963 (has links)
No description available.
894

SATELLITE GROUND OPERATIONS AUTOMATION – LESSONS LEARNED AND FUTURE APPROACHES

Catena, John, Frank, Lou, Saylor, Rick, Weikel, Craig 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Reducing spacecraft ground system operations costs are a major goal in all missions. The Fast Auroral Snapshot (FAST) flight operations team at the NASA/Goddard Spacecraft Flight Center developed in-house scripts and procedures to automate monitoring of critical spacecraft functions. The initial staffing profile of 16x7 was reduced first to 8x5 and then to “lights out”. Operations functions became an offline review of system performance and the generation of future science plans for subsequent upload to the spacecraft. Lessons learned will be applied to the challenging Triana mission, where 24x7 contact with the spacecraft will be necessary at all times.
895

SYNTHETIC APERTURE GROUND PENETRATING RADAR IMAGING FOR NONDESTRUCTIVE EVALUATION OF CIVIL AND GEOPHYSICAL STRUCTURES

Brown, Andrew, Lee, Hua 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Synthetic-aperture microwave imaging with ground penetrating radar systems has become a research topic of great importance for the potential applications in sensing and profiling of civil and geophysical structures. It allows us to visualize subsurface structures for nondestructive evaluation with microwave tomographic images. This paper provides an overview of the research program, ranging from the formation of the concepts, physical and mathematical modeling, formulation and development of the image reconstruction algorithms, laboratory experiments, and full-scale field tests.
896

A MODULAR APPROACH TO LANDSAT 7 GROUND PROCESSING

Mah, G. R., Pater, R., Alberts, K., O’Brien, M., Senden, T. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / Current Landsat 7 processing is based on a single-string, multifunction approach. A follow-on system has been designed that repartitions functions across multiple hardware platforms to provide increased flexibility and support for additional missions. Downlink bit stream acquisition has been moved to lower cost systems functioning as “capture appliances” with high-speed network interconnections to Level 0 processing on generic compute servers. This decouples serial data stream acquisition from the processing system to allow the addition or replacement of compute servers, without the reintegration of specialized high-speed capture hardware. Moreover, it also allows the easy integration of new systems and missions without extensive system redesign or additional software.
897

THE IMPLEMENTATION OF NASA’s LOW EARTH ORBITER – TERMINAL AS AN AUTONOMOUS GROUND NETWORK ASSET

Bundick, Steven N., Kremer, Steven E. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / As part of NASA’s goal to reduce costs for satellite telemetry and command ground support, the ground network has installed two autonomous ground terminals known as Low Earth Orbiter - Terminal’s, or LEO-T’s. These systems are highly automated and were developed to prove the feasibility of supporting multi-mission satellites in a handsoff mode.
898

A Low-Cost, Autonomous, Ground Station Operations Concept and Network Design for EUVE and Other Earth-Orbiting Satellites

Abedini, A., Moriarta, J., Biroscak, D., Losik, L., Malina, R. F. 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / The Extreme Ultraviolet Explorer (EUVE) satellite was designed to operate with the Tracking and Data Relay Satellite System (TDRSS) and Deep Space Network (DSN). NASA, the Jet Propulsion Laboratory and the Center for EUV Astrophysics have been evaluating a commercially available ground station already used for NASA's Low Earth Orbit (LEO) weather satellites. This ground station will be used in a network of unattended, autonomous ground stations for telemetry reception, processing, and routing of data over a commercial, secure data line. Plans call for EUVE to be the initial network user. This network will be designed to support many TDRSS/DSN compatible missions. It will open an era of commercial, low-cost, autonomous ground station networks. The network will be capable of supporting current and future NASA scientific missions, and NASA's LEO and geostationary weather satellites. Additionally, it could support future, commercial communication satellites in low, and possibly medium, Earth orbit. The combination of an autonomous ground station and an autonomous telemetry monitoring system will allow reduction in personnel. The EUVE Science Operations Center has already reduced console work from three shifts to one by use of autonomous telemetry monitoring software.
899

EVOLUTION OF THE COST EFFECTIVE, HIGH PERFORMANCE GROUND SYSTEMS: A QUANTITATIVE APPROACH

Hazra, Tushar K., Stephenson, Richard A., Troendly, Gregory M. 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / During the recent years of small satellite space access missions, the trend has been towards designing low-cost ground control centers to maintain the space/ground cost ratio. The use of personal computers (PC) in combination with high speed transputer modules as embedded parallel processors, provides a relatively affordable, highly versatile, and reliable desktop workstation upon which satellite telemetry systems can be built to meet the ever-growing challenge of the space missions today and of the future. This paper presents the feasibility of cost effective, high performance ground systems and a quantitative analysis and study in terms of performance, speedup, efficiency, and the compatibility of the architecture to commercial off the shelf (COTS) tools, and finally, introduces an operational high performance, low cost ground system to strengthen the insight of the concept.
900

The Design of Telemetry Acquisition and Analysis Vans for Testing Construction and Mining Equipment

Jury, Owen T. 10 1900 (has links)
International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Caterpillar Inc. has over 25 years of experience using instrument vans equipped with telemetry to support product testing. These vans provide the capability to instrument the product, to acquire telemetered data, and to analyze the data. They are being used in tests performed on construction and mining equipment at Caterpillar's proving grounds and at customer job sites throughout North America. This paper presents a design summary of the newest generation vans. It starts with an overview of the major subsystems and concentrates on the Caterpillar developed software that tightly integrates the various hardware and software components. This software greatly enhances the productivity of the system and makes it possible for the van to perform a large variety and quantity of tests required by our internal customers.

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