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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

Space in Space: Privacy Needs for Long-Duration Spaceflight

Aiken, Jo 05 1900 (has links)
Space exploration is a uniquely human activity. As humans continue to push the limits of exploring the unknown, they have sought knowledge supporting the sustenance of life in outer space. New technologies, advancements in medicine, and rethinking what it means to be a “community” will need to emerge to support life among the stars. Crews traveling beyond the Moon will rely on the development of new technologies to support the technological aspects of their missions as well as their quality of life while away from Earth. Likewise, through advancements in medicine, scientists will need to address remaining questions regarding the effects of long-duration spaceflight on the human body and crew performance. Space explorers must learn to utilize these new technologies and medical advancements while learning to adapt to their new environment in space and as a space community. It is important that researchers address these issues so that human survival beyond Earth is not only achievable but so that life among the stars is worth living and sustaining. This thesis addressed these issues in an attempt to extend the trajectory of space exploration to new horizons.
52

A systems analysis of space industrialization

Akin, D. L. (David L.) January 1981 (has links)
Thesis (Sc.D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1981. / Microfiche copy available in Archives and Barker. / Includes bibliographical references. / by David L. Akin. / Sc.D.
53

Galilean moon tour using simplified trajectory computational techniques

Williams, Ryan. January 2006 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (February 23, 2007) Includes bibliographical references.
54

Exhaled nitric oxide in extreme environments

Hemmingsson, Tryggve, January 2009 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2009. / Härtill 4 uppsatser.
55

Model predictive control for spacecraft rendezvous

Hartley, Edward Nicholas January 2010 (has links)
No description available.
56

Assembly, Integration and Thermal Testing of the Generic Nanosatellite Bus

de Carufel, Guy 13 January 2010 (has links)
This thesis describes the assembly and integration procedures, methods and strategies used for the Generic Nanosatellite Bus (GNB) developed at the Space Flight Laboratory. The design of the interconnection medium routing will be presented and aspects of thermal testing such as thermal shock procedures and the satellite support structure design for the thermal vacuum testing. The compliance of the assembly, integration and testing requirements is demonstrated through validation and implementation. Step by step procedures are presented for GNB assembly, solar cell bonding and thermal tape application. The evolution of the integration design is described based on optimizing efforts and GNB design changes. Flexible circuits are presented as an alternative to the conventional harness for future missions. Finally, general assembly, integration and thermal testing recommendations are offered to add to the wealth of knowledge acquired by SFL in the proper design of nanosatellites.
57

Design, Test, Calibration and Qualification of Satellite Sun Sensors, Power Systems and Supporting Software Development

Gavigan, Patrick 30 May 2011 (has links)
This thesis describes technologies developed for nanosatellites at the Space Flight Laboratory. A critical ground station component, the Terminal Node Controller, was upgraded in order to support Generic Nanosatellite Bus and future missions. Sun sensor requirements and operation were reviewed, followed by details of the author's work in executing the acceptance testing on these parts, including thermal shock testing, thermal functional testing, calibration, system level testing and on orbit commissioning. A new calibration test process was developed, along with supporting structure and software to ease the testing process, producing accurate calibration parameters and expected performance results for the sensors. A thermal qualification campaign was completed, demonstrating that sun sensors are capable of functioning with negligible performance degradation after exposure to extreme temperatures. A process for installing the sun sensor pin hole was developed using photolithography. Finally, power subsystem analysis for the NEMO-AM mission is presented.
58

Assembly, Integration and Thermal Testing of the Generic Nanosatellite Bus

de Carufel, Guy 13 January 2010 (has links)
This thesis describes the assembly and integration procedures, methods and strategies used for the Generic Nanosatellite Bus (GNB) developed at the Space Flight Laboratory. The design of the interconnection medium routing will be presented and aspects of thermal testing such as thermal shock procedures and the satellite support structure design for the thermal vacuum testing. The compliance of the assembly, integration and testing requirements is demonstrated through validation and implementation. Step by step procedures are presented for GNB assembly, solar cell bonding and thermal tape application. The evolution of the integration design is described based on optimizing efforts and GNB design changes. Flexible circuits are presented as an alternative to the conventional harness for future missions. Finally, general assembly, integration and thermal testing recommendations are offered to add to the wealth of knowledge acquired by SFL in the proper design of nanosatellites.
59

Design, Test, Calibration and Qualification of Satellite Sun Sensors, Power Systems and Supporting Software Development

Gavigan, Patrick 30 May 2011 (has links)
This thesis describes technologies developed for nanosatellites at the Space Flight Laboratory. A critical ground station component, the Terminal Node Controller, was upgraded in order to support Generic Nanosatellite Bus and future missions. Sun sensor requirements and operation were reviewed, followed by details of the author's work in executing the acceptance testing on these parts, including thermal shock testing, thermal functional testing, calibration, system level testing and on orbit commissioning. A new calibration test process was developed, along with supporting structure and software to ease the testing process, producing accurate calibration parameters and expected performance results for the sensors. A thermal qualification campaign was completed, demonstrating that sun sensors are capable of functioning with negligible performance degradation after exposure to extreme temperatures. A process for installing the sun sensor pin hole was developed using photolithography. Finally, power subsystem analysis for the NEMO-AM mission is presented.
60

A minimalistic model of resistance training : effects on skeletal muscle function during unloading

Schulze, Kimberley E. January 1999 (has links)
Since astronaut time and energy are at a premium, effective countermeasures must be designed to maximize benefits while minimizing time/energy cost. Therefore, our intent was to design and evaluate a low volume, high intensity resistance training program (RTP) on the preservation of knee extensor and plantar flexor size, strength and neuromuscular function in response to unloading. A total of 32 subjects participated. Sixteen men underwent 21 days of unilateral lower limb suspension (ULLS) and were assigned to control (no RTP) (ULLS-CON, n=8) or countermeasures (ULLS-CM, n=8). The remaining subjects were ambulatory for 21 days and were assigned to no RTP (n=8) or countermeasures (n=8). Countermeasure subjects performed RTP every third day during the suspension period (total=6). The RTP consisted of 2 maximal isometric contractions (MVC), 1 set of 10 concentric/eccentric isotonic repetitions, and 1 set to exhaustion, at 80% of 1-repetition maximum (1RM). There was no change in muscle function in ambulatory subjects. Whole muscle cross sectional area (CSA) measured by computed tomography (CT) decreased 7% (thigh) and 7.5% (calf) in ULLS-CON (p<0.05), and was unchanged in ULLS-CM. MVC decreased 16.5% in both quadricep and calf muscles in ULLS-CON (p<0.05) and increased 6% in the quadricep of ULLSCM (p<0.05). Maximal concentric (CNC) and eccentric (ECC) isokinetic strength decreased an average of 18% and 17% in the knee extensors and plantar flexors of ULLS-CON, respectively (p<0.05) and was unchanged in ULLS-CM. 1RM decreased 16% in both quadricep and calf of ULLS-CON (p<0.05) and was unchanged in ULLSCM. Knee extensor work capacity, evaluated during 30 maximal CNC contractions (3.14 rad•sec-'), decreased 18% in ULLS-CON (p<0.05). Neural activation of knee extensors and plantar flexors was measured by electromyography (EMG). Submaximal v.lat, v.med, gast and sol EMG increased in ULLS-CON (p<0.05) and was unaltered in ULLSCM. Maximal EMG decreased 20% and 26% in v.1at and v.med, respectively in ULLSCON (p<0.05). ULLS-CM showed a 15% and 28% increase in v.med and gast maximal EMG (p<0.05). These data suggest knee extensor and plantar flexor muscle size, strength and neuromuscular function were preserved during unloading using a low volume, high intensity RTP performed every third day. / School of Physical Education

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