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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.
111

EXPERIMENTAL AND NUMERICAL ANALYSIS OF ENVIRONMENTAL CONTROL SYSTEMS FOR RESILIENT EXTRA-TERRESTRIAL HABITATS

Hunter Anthony Sakiewicz (15339325) 22 April 2023 (has links)
<p> As space exploration continues to advance, so does the drive to inhabit celestial bodies. In<br> order to expand our civilization to the Moon or even other planets requires an enormous amount of research and development. The Resilient Extra-Terrestrial Habitat Institute is a NASA funded project that aims to develop the technology needed to establish deep-space habitats. Deep-space inhabitation poses many challenges that are not present here on earth. The Moon, for example, has temperatures that range from -233−123°C. Aside from the extreme temperatures, a variety of thermal loads will need to be handled by the Environmental Control and Life Support System (ECLSS). Aside from the research and architecture of the International Space Station’s ECLSS, very little information is known about disturbances related to the thermal management of extra- terrestrial habitats.<br> </p> <p>RETHi is developing a Cyber-Physical Testbed (CPT) that represents a one-fifth scale<br> prototype of a deep space habitat. In order to answer difficult research questions regarding ECLSS and thermal management of a deep-space habitat, a heat pump was modeled and validated with the physical part of the CPT. Once validated, the heat pump model is able to accurately predict the steady state behavior given the indoor and outdoor conditions of the testbed. When coupled with the interior environment (IE) model, it gives insight into the system’s requirements and response. Experimental testing was conducted with the heat pump in order to validate the model. After the model was validated, a series of parametric studies were conducted in order to investigate the effects of varying thermal loads and dehumidification. Since the groundwork was laid through model development and experimentation, future work consists of designing a more versatile heat pump to test a variety of disturbance scenarios. Although the heat pump model is specifically designed for the CPT, it proves to be versatile for other closed and pressurized environments such as aircraft and clean rooms according to the analysis of dehumidification and dependence on pressure. </p>
112

A Wave Home : Exploring furniture for the moon

Miller, André January 2023 (has links)
In this thesis, I have explored the possibilities of what furniture can look like on a moon base. How they will be made and what resources to use. What will the living conditions be like and why producing on a faraway place is important for future interstellar missions. By combining art and design, I will present a realistic concept that fits the need of the astronauts stationed on the moon and know what one might need when on a moon station.
113

OSIRIS-REx Surface Imaging to Constrain Properties of the Asteroid (101955) Bennu

Allen, Alicia 01 January 2022 (has links) (PDF)
This study used images taken from the OSIRIS-REx spacecraft sample-return mission and projected onto a three-dimensional shape model to determine surface properties of the asteroid (101955) Bennu. Two major projects were completed. For the first project, images of the pre-sampled Nightingale site and post-sampled Nightingale were compared to determine how the TAGSAM sampling maneuver effected the surface of the asteroid directly at the sampling site and in the surrounding area. This analysis demonstrated how spacecraft can potentially affect a small body during this and future sample-return missions. For the second project, several craters on Bennu’s surface were selected and all of the boulders within their rims and up to one crater radius outward from their rims were counted and measured. The interior and exterior of all craters were compared which determined that there is a pattern that supports the existence of a subsurface layer of finer-grained material which could be responsible for cohesion on Bennu and potentially other rubble-pile asteroids
114

Developing Origami-Based Approaches to Realize Novel Architectures and Behaviors for Deployable Space Arrays

Pehrson, Nathan Alan 01 October 2019 (has links)
Origami-based approaches for the folding of thick materials for specific application to large deployable space arrays is explored in this work. The folding approaches presented utilize strain energy, spatial kinematics, membranes, compliant mechanisms, and or in combination together to fold finite-thickness materials viewed through the lens of origami-based engineering. Novel architectures and behaviors of mechanisms are developed to achieve packaging efficiency, deployment, and self-stiffening. A method for the folding of monolithic thick-sheet materials is developed by incorporating compliant mechanisms into the material itself to strategically add degrees of freedom. The design and characterization of the compliant mechanisms with consideration to stress, material selection, and stiffness is given. Other folding approaches developed include a bistable vertex and a double-membrane method.The folding approaches derived are applied to larger tessellations and folding patterns. The fold patterns developed and used lend themselves well to large reconfiguration and the combination of the folding approaches with the patterns create opportunities to fabricate products out of thick, functional materials. Of specific interest is the application of these approaches and patterns to the field of deployable space arrays. Spatial kinematics, computational dynamics, physical tests, and systems engineering are used to develop an array architecture that is self-deployable, self-stiffening, and retractable. This architecture is shown to open the design space of large deployable arrays by increasing packaging efficiency and mass.The method, approaches, and architectures developed by this dissertation contribute to the fields origami-based engineering and deployable space arrays. While a focus of this work is the advancement of space technologies, the depth of the analyses provided are transferable to other origami-based and compliant-mechanism disciplines.
115

Conflicting Institutional Logics and the Loose Coupling of Practice with NASA's Enterprise Information System

Berente, Nicholas January 2009 (has links)
No description available.
116

Turboelectric Distributed Propulsion System for NASA Next Generation Aircraft

Abada, Hashim H. January 2017 (has links)
No description available.
117

Electrical Power and Storage for NASA Next Generation Aircraft.

Al-Agele, Saif January 2017 (has links)
No description available.
118

EFFECTS OF FEATURE PRESENCE/ABSENCE AND EVENT ASYNCHRONY ON VIGILANCE PERFORMANCE AND PERCEIVED MENTAL WORKLOAD

FINOMORE, VICTOR S., JR. 14 July 2006 (has links)
No description available.
119

NASA/LOCKHEED MARTIN-CSOC GROUND NETWORK AND SPACE NETWORK INTEROPERABILITY TESTBED

Martinez, Lindolfo, Muzny, Larry 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / NASA and Lockheed Martin-CSOC have been supporting in the development of plans for the evolution of NASA’s Ground Network (GN) and Space Network (SN), and where possible, synchronizing those plans with plans for the evolution of the Deep Space Network (DSN). This paper describes a recommendation for a common ground system communication architecture based on the Consultative Committee for Space Data Systems (CCSDS) Space Link Extension (SLE).
120

LINK ANALYSIS FOR THE NEAR EARTH ASTEROID PROSPECTOR

Barton, Randal L. 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / The Near Earth Asteroid Prospector (NEAP) has a scheduled launch date between mid- 1999 and mid-2000, and will encounter a yet to be determined near Earth asteroid (1.1 - 2.2 AU distance from Earth) some ten months later [2]. The purpose of this mission is not only to collect valuable scientific and geological data, but to also determine the value of the asteroid’s materials for possible mining and exploitation [2], [3]. The purpose of this paper is to detail frequency allocation issues and to determine possible return (space to Earth) data rates associated with deep space communications with the NEAP spacecraft.

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