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Control systems for in-orbit microgravity facilitiesYork, Max January 1992 (has links)
No description available.
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Re-visioning the public in the city of difference : poetics and politics in post-reform Guangzhou, ChinaQian, Junxi January 2013 (has links)
This thesis attempts to contribute to the literature on urban public space. It focuses on urban China which is a non-Western social context and also undergoing unprecedented social, economic and cultural transformation since its market-reform in 1978. It suggests that the socio-spatial restructuring of post-reform Chinese cities has opened up new possibilities for examining the complex entanglement of social changes, spatial practices in the public and the reconstitution of social relations. This thesis first uses an ideal-predicament-practice framework to develop an overview of the extant literature on urban public space. It argues that in classic social theories public space is associated with two normative ideals, namely the ideal of political expression and the ideal of unfettered social engagement. However, since the 1970s most studies in Anglophone sociology, geography and urban studies have tended to focus on the decline of the public sphere. This rhetoric of decline is manifested in three major strands of research, namely the decrease of civic participation in public communication, the privatization of public space and the regulation of public space. In this thesis, I argue that this body of literature only presents a partial picture of the ongoing construction of the public realm. While it certainly offers a solidly critical stance in the examination of urban change, it does not need to lead us to the impression that the public sphere is no longer central to our civic and political life. Many studies in this literature suffer from two epistemological problems. First, many of these studies are undergirded by a closed perspective which reifies the binary oppositions of exclusion and inclusion, absence and presence. Being visible in the public is unproblematically seen as socially empowering, while exclusion is considered to reduce the social and political relevance of public space. Second, this body of literature also delineates the public sphere in terms of fixed types of spaces which accommodate fixed uses and produce fixed social and cultural meanings. Which has been dispensed with, as a result, is an epistemologically more open approach which actively locates and analyzes people’s actually existing practices and actions related to the production and construction of competing visions of publicness. Thus I argue that the social and political potentials of public spaces are never determined prior to social members’ active participation in the public realm. Public space is constantly made and remade through engaged practices which produce and construct the social and cultural turfs of space from below. Armed with this perspective, this thesis will use four chapters of empirical research to elucidate the complex socio-spatial dynamics associated with the production and construction of public space. Four stories are narrated in this thesis: 1. The emergence of grassroots leisure class in China’s urban public space and the possibilities which it has created for ordinary people to enact and perform their cultural identities. 2. Gay men’s cruising in Guangzhou’s People’s Park and the ways in which gay men negotiate a self-disciplining subjectivity in relation to their public presence and their “deviant” and “abnormal” cultural identity. 3. The construction of improvised grassroots public and counterpublic in the singing of socialist “Red Songs” and how this collective public culture provides opportunities for the production and reproduction of political identities and political discourses. 4. The regulation of motorcycle taxis and the ways in which visions of public space are intrinsically implicated in the constitution of dominant knowledge, social relations and power structures.
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Space Qualified Magnetic DiskTreff, Arthur J., Forella, John F. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1993 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Highly reliable data storage for satellites and spacecraft is a challenging technology. The space environment is a unique combination of many environmental factors which impact the reliability and even the very survival of electronic systems. The need for space qualified memory is becoming even more important with the advent of on-board data processing which requires rapid access to large data bases. This paper describes the unique environmental and design considerations that must be taken into account for a magnetic disk that is designed to operate for years in the space environment.
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The International Space Station comparative maintenance analysis model (CMAM)Soldon, Brian T. 09 1900 (has links)
Approved for public release; distribution is unlimited / The National Aeronautic and Space Administration (NASA) and its prime
contractors currently use a software tool called RMAT (the Reliability and
Maintainability Assessment Tool) for the forecasting of Orbital Replacement Unit
(ORU) failure rates and associated maintenance demands for the International
Space Station (ISS). This thesis introduces a new model: CMAM (the
Comparative Maintenance Analysis Tool), which was developed to replicate
some of the basic functionality of RMAT in order to provide a comparative look at
RMAT results. The CMAM program, developed in Visual Basic.net and
dynamically linked to a Microsoft ACCESS database, focuses on a
representative set of critical Orbital Replacement Units (ORUs that represent key
items that require both internal and external maintenance in both pressurized and
un-pressurized storage) and generated failure rate data for each critical ORU.
The results of the CMAM model are then compared with the failure rates
generated by RMAT program for the same set of critical ORUs. These two
independently developed sets of data are then analyzed against historic failure
rates for these ISS parts. / Major, United States Army
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Strain-based displacement estimation for precision spacecraft structuresColeman, Craig S. 12 1900 (has links)
For precision spacecraft structures used for antennas and reflectors of telescopes, determination of in-orbit structural displacement and its control is very important. While this kind of measurement is relatively easy to carry out in a laboratory setting, it can be problematic in a real world environment. A procedure for the real-time determination of displacements at any point of a vibrating body can be utilized by measuring strain that is present. The procedure could employ measurement devices like Fiber Bragg Gratings, which are capable of very fine strain measurements. This thesis presents the finite element analysis of a truss similar to the NPS Space truss to observe the behavior of the strain relative to the displacement. A relationship between strain and displacement for the truss is derived.
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Army space and transformationScherer, Clay S. 09 1900 (has links)
The Army is undergoing a Transformation process, the outcome of which will be an enhanced warfighting capability via the Objective Force. Space is a key enabler for the Army's Objective Force capabilities and Joint combat operations. The Army has a long history of success in the space mission area that stretches back to the 1940s. The Army established doctrine for conducting space operations in support of the Objective Force. This thesis explains why the Army is involved in space from historical, doctrinal and policy perspectives. The Army created force structure for Space Support Elements (SSE) at the tactical level and organic to Division headquarters, and has planned and proposed additional space elements at the Brigade, Corps and Army organizational levels. The FA40, (Space Operations), Career Field is a relatively new personnel category that brings space products and services to the warfighter. Proper distribution of the FA40 personnel pool is a critical part of assuring the success of the FA40 Career Field. This thesis presents recommendations on how the Army can better organize its space force structure, allocate personnel and develop future space capabilities requirements documents to ensure relevancy in a transformed Army.
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Ground-based high energy power beaming in support of spacecraft power requirementsGuoan, Christopher M. 06 1900 (has links)
This thesis investigates the feasibility of projecting ground-based laser power to energize a spacecraft electrical bus via the solar panels. The energy is projected through a telescope, using modern optical compensation systems, at controlled wavelengths. Research conducted on high-energy lasers has matured to the point today, that the bulk of the power required by spacecraft on orbit can be projected from the surface of the earth. With battery life being the greatest limitation on spacecraft lifespan, the ability to provide electrical power from the surface to a satellite in eclipse with degraded batteries could mean multi-billion dollar cost savings by extending the lifetime of current and future satellites. / US Navy (USN) author.
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Object and spatial subsystems in mental imagery : behavioral investigationsWatson, Maria Eugenie, 1966- 01 February 2017 (has links)
Recent evidence indicates that mental imagery comprises independent object and spatial subsystems. The experiments reported here are behavioral studies of these subsystems. Experiments 1 and 2 used the selective interference paradigm to determine whether these subsystems could be behaviorally dissociated. In Experiment 1, subjects listened to descriptions of spatially arrayed objects as they performed an object or spatial interfering task. Recall of the descriptions was expected to demonstrate selective interference of item names or spatial relations as a function of interfering task, however this result was not found. In Experiment 2, subjects indicated whether sentences read in either a spatial or a non-spatial format were true or false. Sentences required either object, spatial, or no imagery. The spatial presentation differentially slowed verification time for high imagery sentences compared to abstract sentences. The prediction that the spatial format would selectively slow verification time for spatial versus object imagery sentences did not obtain for all subjects, however subjects of lower spatial ability showed this pattern of results. Experiments 3-5 isolated one contribution of spatial imagery to memory: Its ability to preserve the sequential order of events. Pictures were presented either in the same location or in different locations. When items in the spatial condition appeared in consecutive locations (Experiment 3), there was no effect on amount recalled, but subjects made fewer sequencing errors. No benefits of the spatial presentation were found with nonconsecutive locations (Experiment 4), presumably because subjects could not remember the order of locations in which the stimuli appeared. When retrieval cues informed subjects of the sequence of locations in which the stimuli had appeared (Experiment 5), subjects were able to use the nonconsecutive locations to aid in sequencing. These studies are interpreted in terms of the anatomical underpinnings of the spatial and object systems. It is argued that connections between these systems make it difficult to separate them through selective interference. Nevertheless, Experiments 3-5 indicate that spatial imagery functions to maintain temporal order information. The two systems therefore appear to serve different and complementary roles in memory. / This thesis was digitized as part of a project begun in 2014 to increase the number of Duke psychology theses available online. The digitization project was spearheaded by Ciara Healy.
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The Relationship Between Room Size and the Limits for Comfortable ConversationWest, Geoffrey B. 05 1900 (has links)
The problem with which this investigation is concerned is that of determining the relationship between room size and the limits for comfortable conversation in dyadic interactions.
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Integration of Vector Valued FunctionsAnderson, Edmond Cardell, III 08 1900 (has links)
This paper develops an integral for Lebesgue measurable functions mapping from the interval [0, 1] into a Banach space.
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