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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.
241

Limited authority adaptive flight control

Johnson, Eric N. 12 1900 (has links)
No description available.
242

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
243

Experimental simulations of a rotating bubble membrane radiator for space nuclear power systems

Al-Baroudi, Homan Mohammed-Zahid 30 March 1993 (has links)
A rotating, flat plate condensation experiment has been developed to investigate the heat of the Rotating Bubble Membrane Radiator (RBMR). The RBMR is a proposed heat rejection system for space applications which uses working fluid condensation on the inside surface of a rotating sphere to reject heat to space. The flat plate condensation heat transfer experiment simulates the microgravity environment of space by orienting the axis of rotation parallel to the gravitational vector and normal to the surface of the plate. The condensing surface is cooled to simulate the rejection of heat to cold surface. The working fluid is a super heated steam. The results obtained include relationships between the overall heat transfer coefficient as a function of the temperature difference between the working fluid and a cold environment, both placed in dimensionless groups, and plate angular rotational speeds. This empirical relationship is useful for choosing the optimum rotational speed for the flat plate radiator given a desired heat rejection load. A RBMR prototype, using full sphere shell, was designed and built completely in this research efforts and ready to be tested in future planned experiments in microgravity environment. This RBMR is the first one ever built to investigate the RBMR concepts experimentally. This study also provides the basis for designing new heat rejection systems utilizing centrifugal forces and condensation phenomena in both space and ground applications. / Graduation date: 1993
244

The study of boundary layer control in a turbopump diffuser with fluid injection /

Pastor, Diego Garcia. January 1996 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1996. / Typescript. Includes bibliographical references (leaves [159]-[161]).
245

Investigation into compactifed dimensions Casimir energies and phenomenological aspects /

Obousy, Richard K. Cleaver, Gerald B. January 2008 (has links)
Thesis (Ph.D)--Baylor University, 2008. / Includes bibliographical references (p. 120-133)
246

High temperature volatility and oxidation measurements of titanium and silicon containing ceramic materials /

Nguyen, QuynhGiao N. January 2008 (has links)
Thesis (Ph.D.)--Cleveland State University, 2008 / Abstract. Includes bibliographical references (p. 110-111). Electronic full text release has been delayed at the author's request until December 31, 2010.
247

Investigation of injector system and gas generator propellant for aft-injected hybrid propulsion /

Pilon, Bryan January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2007. / Includes bibliographical references (p. 194-202). Also available in electronic format on the Internet.
248

Design of a high-efficiency, high-performance zero-voltage-switched battery charger-discharger for the NASA EOS space platform /

Espinosa, Pablo A., January 1994 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Vita. Abstract. Includes bibliographical references (leaves 121-123). Also available via the Internet.
249

Instrumental and environmental effects on RPC-ICA measurements of the cometary ion dynamics at comet 67P/CG

Berčič, Laura January 2017 (has links)
Observations provided from RPC-ICA in combination with the data from RPC-MAG and ROSINA-COPS show that many aspects of the time variability of the detected ions is correlated with the magnetic field or -- to a smaller extent -- with neutral atmosphere density. We also show that not all changes in the cometary ion data reflect the nature of the plasma dynamics, but are a consequence of the instrumental limitations. The main outcome of the article in Appendix 1 is that the cometary ions can be divided into two populations with distinct characteristics. One population we termed the convecting population, is accelerated to higher energies through the interaction with the solar wind. The other population we termed the expanding population is moving radially away from the nucleus in the terminator plane. Both populations exhibit a significant anti-sunward component.In addition we present in this thesis a case with observations day-side of the terminator plane. There we show how the expanding population has a sunward component, consistent with initial radial expansion of the ions from the nucleus which gradually turn into an anti-sunward flow which is then observed in the terminator plane.
250

An Iteration on the Horizon Simulation Framework to Include .NET and Python Scripting

Yost, Morgan 01 June 2016 (has links)
Modeling and Simulation is a crucial element of the aerospace engineering design pro- cess because it allows designers to thoroughly test their solution before investing in the resources to create it. The Horizon Simulation Framework (HSF) v3.0 is an aerospace modeling and simulation tool that allows the user to verify system level requirements in the early phases of the design process. A low fidelity model of the system that is created by the user is exhaustively tested within the built-in Day-in-the-Life simulator to provide useful information in the form of failed requirements, system bottle necks and leverage points, and potential schedules of operations. The model can be stood up quickly with Extended Markup Language (XML) input files or can be customly created with Python Scripts that interact with the framework at runtime. The goal of the work presented in this thesis is to progress HSF from v2.3 to v3.0 in order to take advantage of current software development technologies. This includes converting the codebase from C++ and Lua scripting to C♯ and Python Scripting. The particulars of the considerations, benefits, and implementation of the new framework are discussed in detail. The simulation data and performance run time of the new framework were compared to that of the old framework. The new framework was found to produce similar data outputs with a faster run time.

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