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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.
401

The Phillips Laboratory's Mobile Ground Telemetry Station (MGTS) Configuration and Operations

Flint, Keith D., Mathis, Gregory P., Cronauer, Tom G. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / In support of the various programs that the Phillips Laboratory's Space Experiments Directorate is conducting for the Ballistic Missile Defense Organization (BMDO), the Range Operations Division is developing a mobile telemetry processing system as part of the Mobile Ground Telemetry Station (MGTS) program. The MGTS program's goals are to develop a mission-dedicated telemetry system to supplement current test range capabilities by receiving, processing and recording multiple data streams, sometimes exceeding 10 Mbps. The system will support airborne and suborbital vehicles as well as customized satellite downlinks designed for spacecraft bus State-of-Health monitoring and sensor payload observations. Autonomy and off-road capabilities are also important factors since some of the operations envisioned require deployment to remote field locations where no telemetry processing capabilities currently exist to support the unique data handling requirements. The Phillips Laboratory has completed, with support from Wyle Laboratories and Systems Engineering and Management Company (SEMCO), a "proof-of-concept" mobile telemetry processing system referred to as MGTS #2. Demonstration of the system has been accomplished with the successful deployment and operational support provided to both BMDO's Lightweight Exo-Atmospheric Projectile (LEAP) sub-orbital missions and Miniature Sensor Technology Integration (MSTI) satellite program. MGTS #2 has deployed and is scheduled for further deployment to various operating sites including: White Sands Missile Range (WSMR), NM; Air Force Flight Test Center (AFFTC), Edwards AFB, CA; Vandenberg AFB, CA; and NASA's Wallops Island Flight Facility, VA. While deployed MGTS #2 processes, records and rapidly distributes the critical mission telemetry data conforming to both IRIG and SGLS standards. This paper will describe the evolution of the MGTS program, current hardware configurations and the various mission scenarios that have been supported by the MGTS team.
402

Implementation of CCSDS Telemetry and Command Standards for the Fast Auroral Snapshot (FAST) Small Explorer Mission

Olsen, Douglas 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Recommendations of the Consultative Committee for Space Data Systems (CCSDS) provide a standard approach for implementing spacecraft packet telemetry and command interfaces. The Fast Auroral Snapshot (FAST) Small Explorer mission relies heavily on the CCSDS virtual channel and packetization concepts to achieve near real-time commanding and distribution of telemetry between separate space borne science and spacecraft processors and multiple ground stations. Use of the CCSDS recommendations allows the FAST mission to realize significant re-use of ground systems developed for the first Small Explorer mission, and also simplifies system interfaces and interactions between flight software developers, spacecraft integrators, and ground system operators.
403

ASW-II: Advanced Satellite Workstation for the UHF Follow-On Satellite Program

Hamilton, M. J., Abbott, R., Eggan, P., Golber, D., Hsieh, S., Jordan, L., Le, T., Newcomb, R., Sutton, S., Ton, T., Yu, C., Zechiel, S. 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / ASW-II (Advanced Satellite Workstation, Version II) has been developed and delivered as an operational prototype in support of the Ultra High Frequency (UHF) Follow-On satellite. It provides unified and coordinated real time reception and storage of satellite telemetry, display of both real time and stored telemetry, expert-system analysis of spacecraft status, and an information navigator system that stores and presents information about the spacecraft. The architecture is modular and reconfigurable, and it provides support for multiple analyst workstations. There are several unusual aspects of the design. The entire telemetry history of the satellite is regarded as a continuum by the user, with ASW-II automatically tracking and displaying contact periods. A "streams" mechanism organizes the telemetry in such a way that the user can interactively define new derived parameters and have them presented graphically. Both real time and archived data can be displayed simultaneously. The user has very flexible controls for all display interfaces using mouse and window technologies.
404

Integrated Media Technologies for Satellite Decision Support Systems

Sutton, S. A., Yu, C. S. 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / Within the Aerospace industry, the operational community is facing staff reductions, reduced skill levels, and greater complexity of space assets and space missions. This combination requires that techniques be developed that more efficiently interface a human operator with a complex computer system. Operational support of complex space systems will be greatly facilitated by better presentation of information. The presentation and distribution of complex data must evolve towards formats that are easily and naturally embraced by our sensory systems. Some of the information technologies/techniques that facilitate the presentation of complex dynamic graphical data fall into a category called integrated media. The cost of implementing integrated media (IM) architectures has decreased substantially within in the past five years. While implementation costs continue to recede, the quality and value of information that can be presented using IM technologies continues to improve. Today's IM architect can select a variety of components including digital interactive video, 3D Navigable Worlds, Multimedia Authoring Systems, standardized compressors for IM data, low cost high volume storage systems, and operating system extensions for temporal data management. Together, these components form a solid foundation for the development of a variety of compelling IM architectures. Existing satellite support and mission data processing architectures typically present tabular data for assessment. Some "advanced" systems include 2D graphical projections of the data. System experts are generally trained to correlate relationships between tabular data items. The training required to "learn" these complex relationships is tedious and time consuming. This complexity impedes productivity and as space systems increase in sophistication, these techniques for data assessment are quickly becoming antiquated. The development of a prototype decision support system explores the utility of an integrated media documentation system as part of a full-featured decision support architecture for satellite operations.
405

The art of peace dissuading China from developing counter space weapons / Dissuading China from developing counter space weapons

Meteyer, David O. 06 1900 (has links)
adversary efforts in a direction desired by Washington. Several things become clear during this investigation. First, very little scholarly work exists discussing the concept of dissuasion and the mechanisms used to formulate, implement, and execute it as a defense policy. Second, that while an admirable attempt to lessen the need for more costly policy options such as deterrence and defeat, dissuasion will not prevent China from developing counter space weapons, especially since ground-based jammers that target satellite links have already proven effective. Third, the best chance of dissuading China's efforts to acquire space-based OCS systems is through international treaties and laws.
406

The role of satellite TV channels as news sources in Libya : a study of university students

Elareshi, Mokhtar Hassan January 2012 (has links)
The Libyan media has dramatically changed in recent years. This has been most prominently manifest in the introduction of new satellite television news services. This thesis was designed to investigate two elements – patterns of news media consumption and news credibility in Libya. It examined the patterns of major local and international TV news services operating across different media, broadcast and print, and associations between Libyan students’ consumption of different news media platforms. In this context, it investigated the news consumption habits of young people, with special attention paid to their consumption of pan-Arab news services broadcast via satellite television. It looked at the perception of gratifications students obtained from these news services. It also reported findings on students’ perceptions of the credibility of two local, Al Jamahiriya and Al Libiya TV, and two pan-Arab TV news services, Al Jazeera and Al Arabiya. In order to address the thesis research questions, a survey was administered to a sample of 400 undergraduate students at Al-Fateh University using a stratified random sampling approach, with the sampling strata set by demographic variables. The study found that the new TV news services played an important role in attracting young Libyans with information they desire. The spread of new news media sources (television, radio and print) in Libya has created a new type of customer that transcends national boundaries. Statistical analyses indicated that there are distinct news consumption demographic differences defined in part by news platform (TV versus radio versus print) and in part by the type of news provider (local versus non-local TV news services). The findings were discussed in relation to the growing impact of international satellite broadcast news services and the need for local TV news services to find methods of making themselves distinctive in a way that provides an alternative but still relevant and valued news sources. With regard to news credibility, in general Al Jazeera and Al Arabiya were given higher credibility scores than Al Jamahiriya and Al Libiya news services. Higher credibility ratings, however, were significantly correlated with an increased likelihood of reported watching of both local TV news services, but only one of the pan-Arab TV news services (Al Jazeera).
407

Cell and molecular analysis of intra-operative supraspinatus muscle from patients with rotator cuff injury

Gigliotti, Deanna 14 September 2015 (has links)
Rotator cuff injury is a debilitating condition and when injury cannot be managed through non-operative procedures, surgery is required. To determine explanations for the failure of surgery to restore joint function, human muscle biopsies of supraspinatus were studied compared to deltoid. Histology showed atrophy and a tendency toward fibrosis/fatty infiltration in injured supraspinatus. Findings from AChR-subunit western blot and Sema3A localization around satellite cells suggest supraspinatus denervation. Nucleotide incorporation to quantify satellite cell activation in culture showed a significant increase in BrdU+(active) satellite cells in supraspinatus treated with a nitric oxide-donor drug, but not deltoid muscle. The application of principal component analysis to these data extracted components that suggest variables assaying muscle atrophy, satellite cell activity, and fibrosis contribute strongly to the observed variability. The results suggest supraspinatus muscle of the injured rotator cuff is atrophic, denervated, possibly subject to fibro-fatty infiltration, and support the idea that treatment could promote growth in atrophic supraspinatus to improve functional outcomes. / October 2015
408

Laminin 521 maintains differentiation potential of mouse and human satellite cell-derived myoblasts during long-term culture expansion

Penton, Christopher M., Badarinarayana, Vasudeo, Prisco, Joy, Powers, Elaine, Pincus, Mark, Allen, Ronald E., August, Paul R. 13 December 2016 (has links)
Background: Large-scale expansion of myogenic progenitors is necessary to support the development of high-throughput cellular assays in vitro and to advance genetic engineering approaches necessary to develop cellular therapies for rare muscle diseases. However, optimization has not been performed in order to maintain the differentiation capacity of myogenic cells undergoing long-term cell culture. Multiple extracellular matrices have been utilized for myogenic cell studies, but it remains unclear how different matrices influence long-term myogenic activity in culture. To address this challenge, we have evaluated multiple extracellular matrices in myogenic studies over long-term expansion. Methods: We evaluated the consequence of propagating mouse and human myogenic stem cell progenitors on various extracellular matrices to determine if they could enhance long-term myogenic potential. For the first time reported, we comprehensively examine the effect of physiologically relevant laminins, laminin 211 and laminin 521, compared to traditionally utilized ECMs (e.g., laminin 111, gelatin, and Matrigel) to assess their capacity to preserve myogenic differentiation potential. Results: Laminin 521 supported increased proliferation in early phases of expansion and was the only substrate facilitating high-level fusion following eight passages in mouse myoblast cell cultures. In human myoblast cell cultures, laminin 521 supported increased proliferation during expansion and superior differentiation with myotube hypertrophy. Counterintuitively however, laminin 211, the native laminin isoform in resting skeletal muscle, resulted in low proliferation and poor differentiation in mouse and human cultures. Matrigel performed excellent in short-term mouse studies but showed high amounts of variability following long-term expansion. Conclusions: These results demonstrate laminin 521 is a superior substrate for both short-term and long-term myogenic cell culture applications compared to other commonly utilized substrates. Since Matrigel cannot be used for clinical applications, we propose that laminin 521 could possibly be employed in the future to provide myoblasts for cellular therapy directed clinical studies.
409

Enhancing the water solubility of MyoNovin - a novel skeletal muscle regenerator

Wang, Siyan 16 April 2015 (has links)
Satellite precursor cells are normally quiescent but once activated they support skeletal muscle growth and regeneration by proliferating and differentiating into myoblasts. When an animal suffers from a muscle injury, quiescent satellite precursor cells are activated by nitric oxide (NO). MyoNovin (1-(3,4-Bis-nitrooxy-butoxy)-2-methoxy-benzene), as a NO donor, was developed to provide nitric oxide directly to the skeletal muscle and has been shown to promote satellite cell activation. A potential drawback of the current MyoNovin molecule is its poor water solubility. The aim of this work was to enhance the water-solubility of MyoNovin in order to improve its ease of formulation and possibly enhance its biological activity. The structure of MyoNovin (MN1) was modified with three different functional groups - methanesulfonyl (MN2), benzoic acid (MN3) and acetamide (MN4). The three novel MyoNovin analogs were identified and shown to have similar biological activity as with MyoNovin. All three MyoNovin analogs were found to have better water solubility.#Based on these results, two of the MyoNovin analogs (MN2 and MN3) had much better biological activity with respect to satellite activation and much improved water solubility and may be the most promising candidates for future studies. / May 2015
410

On the Determination of Building Footprints from LIDAR Data

George, Henry C. 15 December 2007 (has links)
A new approach to improve the determination of building boundaries through automatic processing of light detection and ranging (LIDAR) data is presented. The LIDAR data is processed and interpolated into a grayscale image of intensity values corresponding to height measurements. Ground measurements are separated from non-ground measurements by using a progressive morphological filter. With these measurements now distinct, further separation of non-ground measurements into building and non-building measurements is performed by growing regions with similar characteristics. These building areas are then refined, resulting in a ground plan representation of building boundaries, known as building footprints. Several algorithms are then implemented to clean these footprints. A new method is developed to analyze actual known satellite imagery in order to confirm identified building footprints.

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