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The Attitude Determination and Control System of the Generic Nanosatellite BusGreene, Michael R. 16 February 2010 (has links)
The Generic Nanosatellite Bus (GNB) is a spacecraft platform designed to accommodate the integration of diverse payloads in a common housing of supporting components. The development of the GNB at the Space Flight Laboratory (SFL) under the Canadian Advanced Nanospace eXperiment (CanX) program provides accelerated access to space while reducing non-recurring engineering (NRE) costs. The work presented herein details the development of the attitude determination and control subsystem (ADCS) of the GNB. Specific work on magnetorquer coil assembly, integration, and testing (AIT) and reaction wheel testing is included. The embedded software development and unit-level testing of the GNB sun sensors are discussed. The characterization of the AeroAstro star tracker is also a major focus, with procedures and results presented here. Hardware models were developed and incorporated into SFL's in-house high-fidelity attitude dynamics and control simulation environment. This work focuses on specific contributions to the CanX-3, CanX-4&5, and AISSat-1 nanosatellite missions.
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Building NestCarter, Laura 03 August 2007 (has links)
“What does it mean, to make a genuine generalization, to create an objective concrete abstraction of a phenomenon?”—Evald Ilyenkov. As Guy Debord writes in his Society of the Spectacle, “the lack of general historical life also means that individual life as yet has no history.” These poems are my process of coming to understand history, and many of them are critiques of histories per se. If, as Frank O’Hara writes, “these anxieties remain erect,” they also shape the poems that I have written here. I want to be in dialogue with the spectacle that shapes postmodernism. I want to live in communication with the memories of events that have shaped my speech over the years. The title is a struggle to regain a home while not forgetting the displacement of the proverbial poet, a poet to whom I am forever indebted and probably likely to become.
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Protección ultravioleta proporcionada por los textiles:estudio de la influencia de las variables más significativas y aplicación de productos específicos para su mejoraAlgaba Joaquín, Inés M. 15 March 2005 (has links)
La componente ultravioleta de la radiación solar, beneficiosa a pequeñas dosis, puede ser muy nociva por su efecto acumulativo sobre la piel. Los dermatólogos aconsejan protegerse de cantidades excesivas de radiación UV. Generalmente se piensa en la protección de la piel no cubierta, pero hay que tener en cuenta también la protección proporcionada por los tejidos, en particular en prendas ligeras.El objetivo de esta tesis doctoral es el estudio de la protección ultravioleta proporcionada por los tejidos. Mediante diversas técnicas, fundamentalmente la determinación de la transmitancia espectral difusa de radiación ultravioleta, se estudia la influencia de las variables más significativas de las que depende el factor de protección ultravioleta (UPF) de los tejidos.En la primera parte de la tesis, se trata la influencia de la estructura del tejido sobre el UPF. Mediante técnicas estadísticas de planificación de experiencias, se han diseñado tres series de tejidos de Algodón, Modal y Modal Sun, formadas por 27 muestras con una gradación en su estructura. La compacidad del tejido tiene una importante influencia sobre el bloqueo de la radiación UV y el análisis estadístico de los resultados permite su cuantificación. Se obtienen modelos estadísticos que relacionan el UPF de los tejidos con algunos de los principales parámetros de fabricación (título del hilo de urdimbre, título del hilo de trama y densidad de pasadas). Asimismo, se modeliza la influencia sobre el UPF de otros parámetros estructurales de amplio uso en la industria textil (peso por unidad de superficie, cobertura y espesor). Debido a que los resultados muestran que el UPF puede variar muy significativamente en función del tipo de fibra, mediante la técnica FT-IR se analiza la causa del diferente comportamiento de las tres fibras. También se ha estudiado la influencia de las condiciones de uso de las prendas. El UPF puede variar cuando los tejidos se llevan en estado mojado o cuando son sometidos a las tensiones habituales en su contacto con el cuerpo. Se ha obtenido un modelo estadístico para cada fibra que cuantifica la variación del UPF en función de la tensión y humedad, así como del UPF inicial del tejido en estado relajado y seco (representante de la estructura inicial).A partir de tejidos seleccionados en la primera parte, se ha estudiado la aplicación de algunos productos textiles que pueden mejorar el nivel de protección.Se ha estudiado la influencia de la coloración sobre el UPF. Aunque cuando se habla de color se piensa en la región del visible, el espectro de absorción de colorantes también se extiende a las longitudes de onda del UV, por lo que pueden mejorar el UPF. Para cuantificar la influencia de este parámetro, se han aplicado tres colorantes, de una tricromía de colorantes directos, a diferentes concentraciones sobre varios tejidos de Algodón, Modal y Modal Sun, obteniéndose muestras con una gradación de color correspondiente a diferentes intensidades estándar. Se analiza también la influencia de la aplicación, a varias concentraciones, de dos blanqueadores ópticos de diferente estructura química. Estos productos pueden disminuir la transmisión en el UV debido a su capacidad de absorber este tipo de radiación. Del mismo modo se estudia la mejora del UPF mediante el tratamiento con un producto de acabado absorbente de radiación UV, en función de su concentración. Como complemento a este estudio, las imágenes SEM permiten dilucidar si el tratamiento produce modificaciones en la superficie de la fibra. También se analiza la permanencia del efecto de acabado y el impacto ecotoxicológico del tratamiento con el producto.En todos los casos, se han obtenido modelos estadísticos que relacionan el valor de la respuesta UPF con las variables de control en cada una de las partes: el tipo de colorante/blanqueador óptico, la intensidad de la tintura/concentración de producto y el UPF inicial del tejido. Los modelos permiten diseñar tejidos con UPF preestablecido. / The ultraviolet component of the solar radiation, beneficial in small doses, can be very harmful due to its accumulative effect on the skin. Dermatologists recommend the protection of the skin against excessive amounts of UV radiation. Generally, people think in the protection of the uncovered skin, but the protection provided by fabrics should be also taken into account, particularly in light garments.The objective of this doctoral thesis is the study of the ultraviolet protection provided by textiles. By the use of several techniques, fundamentally the determination of the diffuse spectral transmittance of the ultraviolet radiation, the influence of the more significant variables on the ultraviolet protection factor of the fabrics (UPF) is studied. The first part of the thesis deals with the influence of the fabric structure on the UPF. By means of statistical techniques for experiments planning, three sets of fabrics made with Cotton, Modal and Modal Sun are designed. Each set is composed by 27 samples of fabrics with a gradation in their structure. The compaction of the fabric has shown to have an important influence on the blocking of the ultraviolet radiation and the statistical analysis makes possible its quantification. Three statistical models, one for each fibre type, that describe the UPF of the fabrics as a function of some of the main manufacturing parameters (warp yarn number, weft yarn number and weft thread count) have been obtained. Likewise, the influence of other structural parameters widely used in the textile industry (weight per surface unit, percent cover and thickness) on the UPF is modelled. Due to the fact that the results show that the UPF can vary very significantly because of the type of fibre, the cause of the different behaviour of the three studied fibres is analysed by the FT-IR technique. The influence of the wearing conditions of the garments has been studied as well. The UPF can vary when the fabrics are worn in wet state or when they underwent the usual tensions in their contact with the body. A statistical model for each fibre has been obtained, which quantifies the variation of the UPF due to the tension, wetness and the initial UPF of the fabric in relaxed and dry state (which represents the initial structure of the fabric). Taking some fabrics selected in the first part of the thesis, the application of some textile chemicals that can improve the protection level has been investigated. The influence of the coloration on the UPF of the fabrics has been studied. Although when speaking about colour one thinks in the visible range of wavelengths, the absorption spectra of the dyestuffs extends in some part to the UV wavelengths, so they are likely to improve the UPF. To quantify the influence of the colour on the UPF, three dyes of a trichromie of direct dyes have been applied under different concentrations to fabrics made with Cotton, Modal and Modal Sun, therefore obtaining samples with a gradation in colour corresponding to different standard intensities.The influence of the application under several concentrations of two whitening agents of different chemical structure has been as well analysed. These chemicals are likely to decrease the transmittance in the UV region due to their capability to absorb this range of radiation.Likewise, the improvement on the UPF by means of the finishing treatment with an UV absorber under different concentrations has been studied. As a complement to this study, SEM images have been obtained to determine if the treatment produces a modification of the fibre surface. The permanence of the finishing effect and the ecotoxicological impact of the treatment with the UV absorber have been as well analysed.In all the cases, statistics has been use to model the relationship between the response UPF and the control variables in each one of the different parts of the study: the type of dyestuff / whitening agent, the dyeing intensity / concentration of the chemical and the initial UPF of the fabric. The models allow to design fabrics with a pre-established UPF.
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Melankoli och ironi : Strategier för hållbar utveckling / Melancholy and Irony : Strategies for sustainable developmentSvensson, Morgan January 2011 (has links)
The purpose of this study is to show what melancholy and irony in my poems express and what techniques that are used to accomplish these effects. Many theorists, among them Sigmund Freud and Julia Kristeva, characterize melancholy as an experience of loss, and therefore one of my questions is what kind of losses appear in my poetry. In search for an answer I analyze the texts from both a psychoanalytic and a sociological point of view. In the latter perspective I discuss the postmodern society using concepts from contemporary thinkers like Zygmunt Bauman, Fredric Jameson and Jean Baudrillard. Finally, I also examine if melancholy has an influence on the form of the poems. The result of my investigation shows that the psychoanalytic perspecitve of Kristeva with great accuracy can predict the elements in melancholy poems but not provide interesting information about the cultural content in them. On the contrary, the sociological perspective shows a multitude of interesting connections between the feeling of loss in the poems and a dysfunctional society. My analysis also shows that both the melancholy and the irony in the poems are expressions of an alienation in a society that is characterized by an abundance of invading images, a rigid system of self control in an ”open society” and the extreme difficulty to plan for the future as a consequence of the ”unleashed market”. Furthermore, several poems have an abrupt irony in the ending and I establish that this technique has several functions in common with the parabasis in the comedy of the Greek Attic theatre. / Morgan Svensson
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Autobiography Re-defined: A Discussion of Anita Endrezze¡¦s Life Writing Throwing Fire at the Sun, Water at the MoonChu, Po-jen 04 August 2010 (has links)
This thesis investigates autobiography from the standpoint of Native Americans, using Anita Endrezze¡¦s work as my anchor text. Drawing on Hertha Wong¡¦s critical position on Native American life writing, I argue that Anita Endrezze¡¦s autobiography, Throwing Fire at the Sun, Water at the Moon (2000), widens the scope of traditional generic limitations. The first chapter is the introduction, which delineates the theme of the thesis and introduces Yaqui history and Endrezze¡¦s family and cultural background. The second chapter analyzes what characterizes Native American autobiography by borrowing Hertha Wong¡¦s standpoint. Hertha Wong is one of the first theorists who yearn to widen the scope of the well-established generic limitations. She theorizes Native American autobiography by putting its etymology (¡§self,¡¨ ¡§life,¡¨ and ¡§writing¡¨) under scrutiny. Wong¡¦s critical base is the key thread of the chapter, and other critics¡¦ positions on Native American life writing are also provided as subsidizing points. Chapter Three revolves around how Endrezee conceptualizes ¡§the self¡¨ in her autobiographical narratives. Wong argues that Native Americans never regard the self as a separate entity from their community. Correspondingly, Endrezze consciously strives to construct a communal self in her personal narratives. To reach the aim, she relates herself to her relatives, her ancestors, and the present-day Yaquis. Besides, through her homing-in journey, she makes a direct connection to her ancestral homeland. Therefore, the representation of the self is not only community-based but also localized. Chapter Four aims to show that Endrezze¡¦s life narratives go beyond the realms of humans. That is, her autobiography resists anthropocentric narratives. She tells stories about the corn, the rain, and a wide variety of plants and animals. It is through the assistance of non-humans that human life is sustainable. Chapter Five aims to argue that Endrezze¡¦s autobiography shatters the fallacy that Native American culture is in demise. On the contrary, it is burgeoning. Endrezze uses her autobiography to fight back. Endrezze attempts to hybridize the languages to pose some reading obstacles to Euro-Americans. Besides, inserting her paintings at the end of autobiography is also a political act because it subverts traditional writing system. She mocks at the mono-dimensional narratives. Chapter Six is my conclusion, in which Endrezze¡¦s cultural and literary contributions are re-affirmed. It is my deep hope that Endrezze¡¦s book can, as her book title symbolizes, become another form of fire/water to continue the life of Yaquis.
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Analysis and Design of a Test Apparatus for Resolving Near-Field Effects Associated With Using a Coarse Sun Sensor as Part of a 6-DOF SolutionStancliffe, Devin Aldin 2010 August 1900 (has links)
Though the Aerospace industry is moving towards small satellites and smaller sensor technologies, sensors used for close-proximity operations are generally cost (and often size and power) prohibitive for University-class satellites. Given the need for low-cost, low-mass solutions for close-proximity relative navigation sensors, this research analyzed the expected errors due to near-field effects using a coarse sun sensor as part of a 6-degree-of-freedom (6-dof) solution. To characterize these near-field effects, a test bed (Characterization Test Apparatus or CTA) was proposed, its design presented, and the design stage uncertainty analysis of the CTA performed. A candidate coarse sun sensor (NorthStarTM) was chosen for testing, and a mathematical model of the sensor’s functionality was derived. Using a Gaussian Least Squares Differential Correction (GLSDC) algorithm, the model parameters were estimated and a comparison between simulated NorthStarTM measurements and model estimates was performed. Results indicate the CTA is capable of resolving the near-field errors. Additionally, this research found no apparent show stoppers for using coarse sun sensors for 6-dof solutions.
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Evaluation of Coarse Sun Sensor in a Miniaturized Distributed Relative Navigation System: An Experimental and Analytical InvestigationMaeland, Lasse 2011 May 1900 (has links)
Observing the relative state of two space vehicles has been an active field of research since the earliest attempts at space rendezvous and docking during the 1960's. Several techniques have successfully been employed by several space agencies and the importance of these systems has been repeatedly demonstrated during the on-orbit assembly and continuous re-supply of the International Space Station. More recent efforts are focused on technologies that can enable fully automated navigation and control of space vehicles. Technologies which have previously been investigated or are actively researched include Video Guidance Systems (VGS), Light Detection and Ranging (LIDAR), RADAR, Differential GPS (DGPS) and Visual Navigation Systems.
The proposed system leverages the theoretical foundation which has been advanced in the development of VisNav, invented at Texas A & M University, and the miniaturized commercially available Northstar sensor from Evolution Robotics. The dissertation first surveys contemporary technology, followed by an analytical investigation of the coarse sun sensor and errors associated with utilizing it in the near-field. Next, the commercial Northstar sensor is investigated, utilizing fundamentals to generate a theoretical model of its behavior, followed by the development of an experiment for the purpose of investigating and characterizing the sensor's performance. Experimental results are then presented and compared with a numerical simulation of a single-sensor system performance. A case study evaluating a two sensor implementation is presented evaluating the proposed system's performance in a multisensor configuration.
The initial theoretical analysis relied on use of the cosine model, which proved inadequate in fully capturing the response of the coarse sun sensor. Fresenel effects were identified as a significant source of unmodeled sensor behavior and subsequently incorporated into the model. Additionally, near-field effects were studied and modeled. The near-field effects of significance include: unequal incidence angle, unequal incidence power, and non-uniform radiated power. It was found that the sensor displayed inherent instabilities in the 0.3 degree range. However, it was also shown that the sensor could be calibrated to this level. Methods for accomplishing calibration of the sensor in the near-field were introduced and feasibility of achieving better than 1 cm and 1 degree relative position and attitude accuracy in close proximity, even on a small satellite platform, was determined.
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Small-scaled Financial Holding Company's operation performance and operation stratagem:Evidence from Jih Sun Financial Holding Company and Waterland Financial Holding CompanyTsai, Chung-Ting 10 June 2005 (has links)
Abstract
To integrate the operating ability and to enhance the operating efficiency of financial institutions, the government of Taiwan promulgated the act of financial holding company in June 2001. Fourteen licenses of financial holding company have been issued since then and the purpose of forming financial holding companies is to increase their international competitiveness which is important to Taiwan since she has become a member of WTO. Among those 14 financial holding companies they are different in scales, in operating strategies and in operating performances. Can those small-scaled financial holding companies survive in the market with increasing competitiveness? Should they merge with other large scaled financial holding companies? The purposes of this thesis are to analyze the previous two questions. In other words, we examine the impact of the Act on the operating strategy and performance of two small-scaled financial holding companies: Jin Sun and Waterland financial holding companies. To address the second issue mentioned previously, we also analyze the operating strategies and performances of the Fubon financial holding company, which is known as having the advantage of stores and branches and of marketing financial products. Our research provides critical operating strategies for Jin Sun and Waterland financial holding companies to enhance their operating performances.
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Study of building solar insolation with 3D GIS¡VAnalysis of shadow shading and solar radiationTao, Cheng-keng 07 December 2005 (has links)
Sunshine, air and water are the vital elements to the human. This study investigated the insolation and solar radiation in Kaohsiung city. Solar radiation on the horizontal and declined plane was calculated. Sun shadow model for urban buildings was constructed for computing accumulated sunshining hours. Horizontal and vertical building shadows were displayed in ArcGIS ¡V the GIS software.
Raster-based data model was used to analyze the effect of sun shadow shading by neighbour buildings. And the effect of shadow shading for solar water heater was also investigated.
According to the results, minor installation error of orientation and decline angles of solar panel will not cause major energy loss. And the distance between the buildings¡Bthe height difference and the orientation between buildings are most important factors which affect optimal installation location of the solar water heater. If there are buildings located to the south, southeast and southwest, and the stories difference between buildings is over three, the installing location should be moved toward north. If buildings are next to each others and the variation of height is large, the efficient of receiving solar radiation will be deteriorated. The larger is the distance between buildings, the better the energy received.
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A Study of the Application of Triangular Marketing Strategies of Service Industry to Market Universities¡GA Case Study of National Sun Yat-Sen University,TaiwanChiu, Yu-Ting 24 July 2007 (has links)
The purposes of this study, taking National Sun Yat-Sen University¡]NSYSU¡^as an example, are to understand the current status of external marketing, internal marketing and interactive marketing endeavors and also to analyze the perceptive difference in different backgrounds of undergraduates of NSYSU. Based on the results of investigation, conclusions and recommendations has been generated, providing analytical design for higher education institutions and also act as a reference for future research.
This study is taking place by the method of interviewing and questionnaire survey. In the section of interviews, a generalized interview summary has been written in the accordance of the documentary analysis. One representative person is selected from among the groups of marketing affairs in National Sun Yat-Sen University, five persons in total and a semi-structured interview method has been adopted. As for the questionnaire survey, based upon the paradigm questionnaires by Wang I-Ting, Lee Chun-Ling, Cheng Jane-Pei et al., a questionnaire was revised from several paradigms by the researcher and named ¡§Questionnaire of National Sun Yat-Sen University Marketing Strategies¡¨, and were delivered to 600 undergraduates of NSYSU with 497 copies returned valid. The results and information collected from the questionnaire were analyzed and compared by statistical methods of item analysis, factor analysis, reliability analysis, mean, standard deviation, t test, one-way ANOVA. After integrating the results both from interviews and questionnaire survey, some conclusions have been reach and several recommendations were raised by the researcher. The conclusions of this research are as follows¡G
1. The current external marketing level of¡@NSYSU is right in the middle level, with perception of ¡§place strategy¡¨ being the highest among students, but the perception experience with ¡§all marketing strategy¡¨ is lowest.
2. The current internal marketing strategy of NSYSU are ¡§refresher course training ¡¨, ¡§participation and authorization¡¨, ¡§positive encourage¡¨, ¡§high-grade environment¡¨ and ¡§congregate the communication¡¨.
3. The current interview marketing level of¡@NSYSU is slightly low, with perception of ¡§service capacity strategy¡¨ being the highest among students, but the perception experience with ¡§service enthusiasm strategy¡¨ is lowest.
4. The senior students have better awareness of school external marketing strategies.
5. The senior students and girl students have better awareness of school interviewing marketing strategies .
According the results as stated above, the researcher advances the suggestions for ¡§National Sun Yat-Sen University¡¨, and ¡§Related Research in the Future¡¨, hoping that they can be of referential value as far as related research and practice are concerned.
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