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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.
101

ACQUISITION AND TRANSMISSION OF SEISMIC DATA OVER PACKET RADIO

Hinterseer, Martin, Wegscheider, Christoph 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 / Research on earthquakes and volcanos is of particular importance in seismic instable regions. To improve opportunities of research and civil defence, continuous coverage of seismic activities of a large area at a certain time is necessary. This paper deals with the issues concerning the collecting of environmental data by a number of autonomous field stations and their transmission to central station through a cost effective low bandwidth packer radio data network. This paper deals with the acquisition, preprocessing and transmission of seismic data. Therefore, a prototype system is discussed, which will be developed at the University of Salzburg, Austria.
102

A Field Monitor System of Rod-pumped Wells Based on GPRS

Zhaodong, Xing, Yanhong, Kou, Qishan, Zhang 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / To enhance the production management of the rod-pumped wells in the oil field, using a high performance single-chip as the processor, a field monitor system based on GPRS is researched and developed. In the paper the hardware design and software design are expatiated, the sampling frequency and determination rules for the running state are analyzed, the rational communication protocol is designed to ensure the reliable message transmission and reduce the communication fees. In the end the field monitor system is successfully implemented and verified in practice, part of data transmission result is illustrated.
103

APPLYING IEEE 1451 STANDARD TO AATIS

Sinclair, Robert, Jones, Charles H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Current legacy acquisition systems such as the Advanced Airborne Test Instrumentation System (AATIS) are custom-built to each individual application with unique sensors and data modules. Replacing, adding, or subtracting sensors requires the system to be removed from service for days, weeks, or even months. This is a result of having to route special wires to each sensor and reprogramming the system with sensor information, calibration data, etc. AR sensor information must be contained in the main system since these systems do not have intelligence at the sensor level. If sensors were to contain information in their own IEEE 1451-compliant transducer electronic data sheet (TEDS), the main system would no longer have to be reprogrammed with this information. This information could then be obtained directly from the sensors when they are inserted into the system. A plug-n-play capability is being added to the system with the development of a standard interface to the system control unit (SCU). This interface, called a Multi-Network Capable Applications Processor (Multi-NCAP), will interface IEEE 1451-compliant smart transducer interface modules (STIMs) to the SCU in the AATIS as well as other legacy systems. With this development, maintenance and new configuration times for the AATIS and other legacy systems will be significantly reduced.
104

A SYNCHRONOUS REAL TIME NETWORK BASED WIRELESS AIRBORNE DATA ACQUISTION SYSTEM

Long, Mark A., Zymowski, Paul H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The purpose of this paper is to present a chronology from a Small Business Innovation Research Program (SBIR) showing the impact of a wireless network architecture on future airborne data acquisition systems. The major advantages and challenges associated with the use of wireless network data acquisition versus wired time division multiplexing systems are rooted in data latency, bandwidth efficient data transmission while maintaining a low bit error rate and not interfering with existing avionics. Many of the issues raised are subtle and complex. It is not the intent of this paper to give these issues the thorough academic and technical analysis they deserve. It is the hope of the authors that this paper will generate awareness and discussion on these issues.
105

A LAYERED APPROACH TO PACKET BASED INSTRUMENTATION

Jones, Sid, Chalfant, Tim 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The telemetry industry must take advantage of the constantly increasing capability and decreasing per unit costs of network technology. The most effective way to do this is to adopt the layered reference model approach that is being used throughout the telecommunications industry. With a layered reference model, the interfaces between the layers are defined. As a layer is changed, the new layer must adhere to the same interfaces as the previous one. This approach easily allows new technology insertion in key areas without affecting the rest of the system. The Navy and the Air Force see this approach as a key component of acquisition reform and have established a comprehensive road map to achieve this goal.
106

The Subminiature Flight Safety System

Woodard, Tracy, Dehmelt, Chris 10 1900 (has links)
ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / Weapons platform testing and monitoring have historically consisted of custom telemetry and flight safety system solutions tailored to the requirements (including Title 10 Mandates) and size constraints of individual platforms. The size of these individual components of these systems has necessitated that warhead replacement to facilitate insertion of these units to support test and evaluation activities. Currently there are no products available to meet these requirements in a miniaturized and modular package. L-3 Communications Telemetry East (L-3 TE) has developed an extensive background in providing solutions to gather vital missile and target information over the last several decades. Under the auspices of Eglin AFB, L-3 TE is leading a multi-disciplinary team to design and develop the Subminiature Flight Safety System (SFSS) to support existing and new weapons applications. SFSS is a universal, small, and low cost redundant flight termination system (FTS) that incorporates encoding, processing and TSPI capacities that provides critical health/safety/welfare monitoring and allows for highly efficient telemetering of all weapon application and FTS data. The SFSS is intended as a solution to allow weapon system developers, test agencies, and range safety officers the ability to track, monitor, and if necessary, terminate all types of weapon systems. It is designed to interface with newly developed weapon systems, while providing backward compatibility to meet existing requirements with minimal modifications to the weapon. The SFSS components are intended to significantly reduce the cost and improve the quality of test support by providing a highly integrated solution that minimizes physical intrusion into weapon systems, by eliminating the need for warhead removal. In addition, a common hardware platform will reduce overall system cost of acquisition and maintenance to the government, a key element in today's world of stressed budgets.
107

Comparison of direct-s modes produced by different source types

Erturk, Nurtac 23 September 2014 (has links)
Compressional and shear body waves generated by a seismic source can be analyzed using vertical seismic profiling (VSP) data-acquisition procedures. If a goal of exploration geophysics is to study the physics and exploration applications of shear waves, it is important to know how much S-wave energy a source puts into the earth. To maximize S-wave created by a source, considerable effort has been expended to create surface sources that apply horizontally directed impulses to the earth (horizontal vibrators and horizontal impacts). In my project, radial shear (SR) and transverse shear (ST) waves generated by different types of sources and recorded by multicomponent receivers in a VSP well are examined and compared. The research question is ‘can a vertical-impact source create shear wave energy equivalent to the S-wave energy produced by standard horizontal-force shear-wave sources?’ To quantify the energy of shear-wave modes produced by different kinds of seismic sources, a VSP field test program was conducted at the Devine Test Site owned by The University of Texas at Austin. In the VSP data acquisition phase, the orientation of horizontal geophones is unknown because a borehole geophone rotates as it is lowered into a well, causing the horizontal geophones at each receiver station to be oriented in different azimuths. To study body waves, it is essential that all geophones in a vertical VSP array be oriented in a consistent azimuth. I mathematically rotated multi-component VSP sensors systems to change them from the inconsistent orientation they had at the time of data recording to a user-defined consistent-azimuth coordinate system. This rotation allowed ST and SR wave modes to be identified. After geophone rotation, direct-S wavelet amplitudes were analyzed in 90-ms windows starting at the first-break times of each arriving mode. Analysis of the rotated data showed that SR energy created by a vertical-impact source, a shot-hole explosive, and an inclined-impact source differ only slightly, and that there is essentially no difference in ST energy among these sources. Also, the signal frequency of SR and ST wave modes produced by horizontal-force shear wave sources are essentially the same as the frequency of SR and ST wave modes generated by a vertical-impact source. These test data show that vertical and horizontal vibrator sources produce shear wave modes having amplitudes 1000 times stronger than the other energy sources we tested. Considering the cost of using inclined-impact sources which is relatively expensive compared to using a vertical-impact source, and the difficulty of applying inclined-impacts in some land conditions, it is possible to obtain direct-S data of the same quality by using only a vertical-impact source or a shot-hole explosive. The arguments given above demonstrate that it is not necessary to use inclined-impact sources or horizontal vibrators to produce shear-wave data. S-wave data of the same quality produced by a horizontal-force source are provided by simple vertical-impact sources and shot-hole explosives. / text
108

Development of a computer interface for a clamp-on ultrasonic flow meter

Sundin, Peter January 2007 (has links)
<p>The section for volume, flow and temperature at SP Technical Research</p><p>Institute of Sweden performs measurements of volume, flow and temperature</p><p>in liquids.</p><p>Flow meters are best calibrated in its installation to take sources of error like</p><p>installation effects and the medium into account. If this can be done without</p><p>having to place measurement equipment inside the pipe it will mean several</p><p>practical benefits.</p><p>Since many years, clamp-on ultrasonic flow meters have been available on the</p><p>market. But even with today’s improvements they still have a measurement</p><p>uncertainty in the measurements that is five to ten times too big to make them</p><p>useful as references for calibration procedures.</p><p>This thesis focuses on analysis, using reversed engineering, of an existing</p><p>clamp-on ultrasonic flow meter.</p><p>The goal of the project is evaluation and further development of the ultrasonic</p><p>flow meter’s existing computer interface with the purpose of offering the</p><p>option of using Microsoft Excel and Visual Basic for data acquisition and</p><p>measurement of the flow rate of liquids.</p>
109

A PC-Based Data Acquisition and Compact Disc Recording System

Bretthauer, Joy W., Davis, Rodney A. 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / The Telemetry Data Distribution System (TDDS) solves the need to record, archive, and distribute sounding rocket and satellite data on a compact, user-friendly medium, such as CD-Recordable discs. The TDDS also archives telemetry data on floppy disks, nine-track tapes, and magneto-optical disc cartridges. The PC-based, semi-automated, TDDS digitizes, time stamps, formats, and archives frequency modulated (FM) or pulse code modulated (PCM) telemetry data. An analog tape or a real-time signal may provide the telemetry data source. The TDDS accepts IRIG A, B, G, H, and NASA 36 analog code sources for time stamp data. The output time tag includes time, frame, and subframe status information. Telemetry data may be time stamped based upon a user-specified number of frames, subframes, or words. Once recorded, the TDDS performs data quality testing, formatting, and validation and logs the results automatically. Telemetry data is quality checked to ensure a good analog source track was selected. Raw telemetry data is formatted by dividing the data into records and appending header information. The formatted telemetry data is validated by checking consecutive time tags and subframe identification counter values (if applicable) to identify data drop-outs. After validation, the TDDS archives the formatted data to any of the following media types: CD-Recordable (CD-R) Disc (650 megabytes capacity); nine track tape (180 megabytes capacity); and erasable optical disc (499 megabytes capacity). Additionally, previously archived science data may be re-formatted and archived to a different output media.
110

Acquisition and Near Real-Time Display of Multispectral Test Data from Widely Separated Test Sites

Donlan, Brian, Sabo, Frank 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / As modern weapons grow more sophisticated and capable of operating autonomously, the challenge of testing these weapons has also grown more complex. Seekers may be multispectral and must be able to overcome threat countermeasures. To effectively analyze the performance of these weapons, time-correlated test data must be efficiently, simultaneously acquired from both the weapons' internal busses and from the threat countermeasures' internal communication busses, often in a "live fire" environment. The test data must be transmitted to a central processing station where test personnel may immediately analyze the performance of the weapon with the assistance of scientific visualization techniques. In addition, the data must be captured on permanent media for future playback and more detailed analysis. One solution is to link the test article, threat countermeasures and other test support resources through an Integrated Telemetry System (ITS). Instrumentation to acquire high-speed test data is installed in data collection vans that are remotely located in the vicinity of the article under test or in the vicinity of the threat countermeasures systems or test support resources. The remote vans will be interconnected and linked to a control van which provides a centralized test control and monitoring point. Remote Data Formatter (RDF) instrumentation units, located in the remote vans, can acquire data from and control seekers, sensors, emission sources or other equipment located in or near the remote vans. The RDF units can also format the data for transmission to the control van via either fiber optic or microwave radio links. The data transmitted from multiple remote vans is received by Real-time Data Processing System (RTPS) units located in the control van for merging, processing and recording. Some of the processed data can be transferred to a Host Processing System (HPS) where it can be displayed on color graphic workstations. The control van's HPS workstations provide user-friendly displays and menus for test setup and control. Both the remote and control vans are equipped with secure digital communication systems capable of supporting compressed digital video, audio, high-speed instrumentation data and an Ethernet computer network.

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