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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.
61

Commercial human space flight in the United States : federal licensing and tort liability

Mineiro, Michael C. January 2008 (has links)
In the early 21st century, the private commercial space transportation industry demonstrated that commercial human space flight is both technologically and economically feasible. In 2004, the United States Congress responded by passing legislation authorizing the Department of Transportation to license and regulates commercial human space flight. / This thesis examines and assesses the U.S. commercial human space flight vehicle licensing and regulatory law. Tort liability is inextricably linked to the success of the commercial human space flight industry and to that end this thesis provides an analysis of U.S. tort liability law in the event of a commercial human space flight vehicle accident.
62

Solar sailcraft motion in sun-earth-moon space with application to lunar transfer from geosynchronous orbit

Salvail, James Ronald January 1991 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 1991. / Includes bibliographical references (leaves 152-154) / Microfiche. / xvi,154 leaves, bound ill. 29 cm
63

Nuclear power systems for human mission to Mars /

McGinnis, Scott James. January 2004 (has links) (PDF)
Thesis (M.S. in Astronautical Engineering)--Naval Postgraduate School, Dec. 2004. / Thesis Advisor(s): Sherif Michael. Includes bibliographical references. Also available online.
64

A qualitative focus on gender-based physiological differences and cellular signaling needed for modeling /

Pietarila, Kristel M., January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 101-110). Also available on the Internet.
65

A qualitative focus on gender-based physiological differences and cellular signaling needed for modeling

Pietarila, Kristel M., January 2004 (has links)
Thesis (M.S.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 101-110). Also available on the Internet.
66

Commercial human space flight in the United States : federal licensing and tort liability

Mineiro, Michael C. January 2008 (has links)
No description available.
67

Protein Concentration Elevations in Mouse Lungs Following Sudden Transient Cephalad (+Gz) Acceleration

Gutierrez, Charles J. 01 January 1985 (has links) (PDF)
Laboratory and feral lineages of mice were subjected to cephalad (+GZ) accelerations, for 1.8 seconds, aboard a solid fuel rocket. Spectrophotometric analysis of bronchoalveolar lavage retrieved post launch revealed significant (p < .001) elevations of protein in the lungs of experimental mice. Sudden transient imposition of a mean +GZ acceleration of 6.22 ± .47 (SD) G, at lift-off, may have induced hypervolemia of basilar pulmonary microvasculature with concomitant migration of fluid and protein from intravascular to juxta-alveolar perivascular compartments. Exudates may have entered bronchiolar airways subsequently gravitating toward alveoli.
68

Parameter optimization of atmospheric skip trajectories for use in minimum fuel usage transfer orbits

Martell, Craig Alan 17 March 2010 (has links)
The problem of developing a generalized impulse as a function of a set of parameters is investigated. The proposed generalized impulse alters an existing orbit by producing, over some period of time, a change in velocity, ΔV, as well as a change in position, Δr. The generalized impulse is described by parameters associated with an instantaneous change in velocity as well as parameters associated with an atmospheric skip trajectory. Closed form solutions are obtained through several changes of independent variable, the use of modified Chapman variables and the consequent analytical integration of the uncoupled equations. The closed form solutions contain between two and six parameters depending on the complexity of the desired skip trajectory. Fuel optimal transfer orbits are obtained using the generalized impulse along with Keplerian arcs and instantaneous changes in velocity. Families of coplanar and noncoplanar transfers for circular orbit to circular orbit are numerically generated. The generated transfer trajectories involve the rendezvous of two vehicles. The orbits are not globally optimal but rather optimal for the specified number and type of velocity impulses specified. The optimal solution to the nonlinear problem is determined via sequential quadratic programming which satisfies the Kuhn-Tucker optimality conditions for constrained minimization. It is found that for transfer between coplanar and noncoplanar orbits, solutions using the generalized impulse compare favorably with solutions obtained by optimal control theory. Numerical solution to complex problems involving transfer from general orbit to general orbit were not obtained. / Master of Science
69

Sharing the Shuttle with America: NASA and Public Engagement after Apollo

Kaminski, Amy Paige 30 March 2015 (has links)
Historical accounts depict NASA's interactions with American citizens beyond government agencies and aerospace firms since the 1950s and 1960s as efforts to 'sell' its human space flight initiatives and to position external publics as would-be observers, consumers, and supporters of such activities. Characterizing citizens solely as celebrants of NASA's successes, however, masks the myriad publics, engagement modes, and influences that comprised NASA's efforts to forge connections between human space flight and citizens after Apollo 11 culminated. While corroborating the premise that NASA constantly seeks public and political approval for its costly human space programs, I argue that maintaining legitimacy in light of shifting social attitudes, political priorities, and divided interest in space flight required NASA to reconsider how to serve and engage external publics vis-à-vis its next major human space program, the Space Shuttle. Adopting a sociotechnical imaginary featuring the Shuttle as a versatile technology that promised something for everyone, NASA sought to engage citizens with the Shuttle in ways appealing to their varied, expressed interests and became dependent on some publics' direct involvement to render the vehicle viable economically, socially, and politically. NASA's ability and willingness to democratize the Shuttle proved difficult to sustain, however, as concerns evolved following the Challenger accident among NASA personnel, political officials, and external publics about the Shuttle's purpose, value, safety, and propriety. Mapping the publics and engagement modes NASA regarded as crucial to the Shuttle's legitimacy, this case study exposes the visions of public accountability and other influences -- including changing perceptions of a technology -- that can govern how technoscientific institutions perceive and engage various external publics. Doing so illuminates the prospects and challenges associated with democratizing decisions and uses for space and, perhaps, other technologies managed by U.S. government agencies while suggesting a new pathway for scholarly inquiry regarding interactions between technoscientific institutions and external publics. Expanding NASA's historical narrative, this study demonstrates that entities not typically recognized as space program contributors played significant roles in shaping the Shuttle program, substantively and culturally. Conceptualizing and valuing external publics in these ways may prove key for NASA to sustain human space flight going forward. / Ph. D.
70

Astrofarmaci: Hur antibiotika fungerar i rymden : En scoping review av antibiotikas farmakokinetiska förändringar i rymden. / Astropharmacy: How antibiotics function in space : A scoping review of the pharmacokinetic changes of antibiotics in space

Qanbari, Nadia January 2024 (has links)
Introduction: Space exploration has been a dream of mankind since ancient times, this dream became a reality with the launch of Sputnik in 1957. Since then, significant advances in space technology have enabled humans to travel beyond the Earth's atmosphere. Although some of the health risks are well known, the effect of changes in the pharmacokinetics of drugs and their effectiveness is not yet fully understood. Aim and Method: This study aims to investigate the effect of space travel on the pharmacokinetics of antibiotics. A scoping review method was employed to investigate the changes in the pharmacokinetics of antibiotics during space travel. A search of the PubMed database was performed using the relevant terms. Inclusion criteria included available English full-text articles. A three-step selection process was employed, followed by data analysis and evaluation, to select relevant original scientific articles. Results: The findings suggest that the pharmacokinetics of some antibiotics, such as ciprofloxacin penicillin and benzylpenicillin, may not be significantly altered in microgravity environments. Further research is needed to better understand the implications of space travel on antibiotic efficacy and safety. Conclusion: Current research on the pharmacokinetic changes of antibiotics in microgravity simulations shows little change compared to Earth. However, further research is crucial to understand their bioavailability, durability, and performance in space environments, ensuring the health and safety of space travelers.

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