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O'Brien, Diarmuid Francis. "Conjugated polymer electroluminescence." Thesis, University of Sheffield, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266004.
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Jayaweera, Asanka. "Energy Analysis & Effects on Power Utility of LED's compared to Conventional Bulbs." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-19222.
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Jobanputra, Manish C. "Investigation of Organic Thin Films for Application in Electro-Optic Devices." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1017755544.
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Lea, Arthur Max. "Investigation of the electrical characteristics of GaAsP light-emitting diodes (LED's) under conditions of mechanical stress." Thesis, Brunel University, 1986. http://bura.brunel.ac.uk/handle/2438/7287.
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The main line pursued is the mechanical stressing of light-emitting diodes (LED's) by pressing on the surface with spherically rounded sapphire probes ranging from 100 μm to 500 1m radius of curvature and with forces up to 50 grams weight on the largest probe, care being taken not to exceed the elastic limit of the material, which is estimated to be about 1.4 x 10^9 pascals (14,000 atmospheres) at the central bottom point of the probe. With the diode under forward bias a very wide range of current is covered from 10 mA to about 100 pA in the light-emitting region and from 100 pA to 100 nA in the generation/recombination region - and across the whole range a small decrease in current of about 1 per cent or less is observed. The classical theory of the distribution of stress by a spherical probe has been investigated by a modern computer technique, and by integration of the stress over the whole of the junction interface it is shown that the decrease in current can be ascribed to the increase in band gap of the semiconductor that is brought about by the axial component of pressure stress at right angles to the interface. With the larger currents in the light-emitting region a further decrease in current of the order of 1 per cent or less can be ascribed to heat conduction from the warm surface of the diode to the probe, thereby. lowering the temperature of the interface. Finally, the electrical characteristics of the diode under reverse bias have been investigated, with incident light playing an important role; in the absence of light the extremely small currents (10^-12 to 10^-10 amp) are consistent with thermal generation of carriers similar to the generation/ recombination mechanism for very low currents in the forward direction.
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Vilbrandt, Nicole [Verfasser], Matthias [Akademischer Betreuer] Rehahn, and Markus [Akademischer Betreuer] Biesalski. "Poly(p-phenylen vinylen)e nach Gilch - Konstitutions- und Morphologieeinflüsse auf die Emissionsfarbe und das Ermüdungsverhalten in organischen LED's / Nicole Vilbrandt. Betreuer: Matthias Rehahn ; Markus Biesalski." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2013. http://d-nb.info/1107772338/34.
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Meacham, Rebecca Anne. "Let's do." Cincinnati, Ohio : University of Cincinnati, 2002. http://rave.ohiolink.edu/etdc/view.cgi?acc_num=ucin1038336719.
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Feger, Claudia. "Let's go schmoozing." Universitätsbibliothek Chemnitz, 2005. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200501703.
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Cheung, Yuk-fai, and 張煜輝. "Phosphor-free multilayered LEDs and thin film LEDs." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hub.hku.hk/bib/B50900067.
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The irreversible trend of replacing the conventional incandescence light bulbs and fluorescent tubes with white light emitting diodes (LEDs) aims to use less energy for lighting. Plenty of the commercially available white LEDs are made from blue LED chips with few-micron-thick gallium nitride (GaN) grown on several hundred micron thick transparent sapphire substrates, followed by coating of yellow phosphor powder on top of the chips for converting the emitted blue light to white light. Not only does such approach give the white LEDs a high colour temperature, but also introduces conversion loss from the phosphor powder. The former issue makes users feel unpleasant for living while the latter wastes energy.
Therefore, a new version of phosphor-free multilayered vertically-stacked colour-tunable LED structure is proposed in this thesis such that it allows users to regulate the colour temperature of light source according to their preference. Simultaneously, the device replaces light conversion agents with direct light generation. The fabrication of the proposed device involved the use of backside laser micromachining of trenches on the substrates of the upper layers of basic colour LED chips at a size just enough to fit the wire-bonded wire of lower layer LED chips inside. With equal-sized basic colour LED chips tightly packed together, colour homogeneity of the proposed device is enhanced and thus provides the proposed device the capability to substitute the conventional RGB LED devices with basic colour LED chips separately aligned.
To improve the internal quantum efficiency and light extraction of nitride-based LEDs, thin film photonic crystal LED is proposed. Light and heat trapping sapphire substrate is removed by laser lift-off (LLO), forming GaN thin film on an electrically conductive opaque substrate with better heat conductivity than sapphire. By proper etching, N-dopped GaN layer can be exposed, resulting in the formation of vertical LED. Compared with conventional lateral LEDs with sapphire substrate, carrier path of vertical LED is greatly reduced and hence achieving lower internal resistance. To further boost light extraction, the device top surface is patterned with nanopillars by nanosphere lithography. A monolayer of closely-packed silica nanospheres is patterned on the N-GaN surface by spin coating. It acts as a mask for etching the nanopillars which bandfold lights from diffracted modes to radiative modes located above the light line for extraction.
A typical laser LLO process results in thin films with undopped gallium nitride (U-GaN) surface or N-GaN (after etching) faces up. If P-side up is necessary, the GaN layers are first required to attach to a temporary substrate for LLO and then the LLO exposed surface is adhered to the real substrate before temporary substrate is detached. This method is proposed to relieve the issue of light channeling inside the sapphire substrate of full colour LED micro-display panel fabricated on a single GaN on Sapphire wafer. With the elimination of sapphire, “parasitic” blue emissions from the area surrounding pixels are reduced which in turns improved the observable effects from the microspheres jet-printed on the top surface of the panel.published_or_final_version
Electrical and Electronic Engineering
Master
Master of Philosophy
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Hinshaw, Jesse Creede. "Let's Exchange the Experience." Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/art_design_theses/42.
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The purpose of this study is to attain an understanding of my work for the viewer as well as myself. These works on paper are visual documents illustrating my ideas and opinions about media and its desire for control. Through research, critical thinking, experience, and exposure to media (both wanted and unwanted) I have created imagery that I feel is exemplary of our forced relationship with advertising. In order to accomplish this I studied my influences, and the origin of my current work. Reading upon realization of those influences further informed the work. Every conceivable influence was studied and analyzed, and those studies are contained in this thesis. Questions of audience, scale, medium, and history were also taken into account as a measure to make this thesis cohesive. As an audience for advertisers we must constantly be aware of how our sensitivities are being played upon.
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Hinshaw, Jesse C. "Let's exchange the experience." Atlanta, Ga. : Georgia State University, 2009. http://digitalarchive.gsu.edu/art_design_theses/42/.
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Thesis (M.F.A.)--Georgia State University, 2009.Title from title page (Digital Archive@GSU, viewed July 12, 2010) Cheryl Goldsleger, committee chair; Joe Peragine, Matthew Sugarman, committee members. Includes bibliographical references (p. 22).
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Uribe, Gabriela. "Hey Neighbor! Let's play." Research Showcase @ CMU, 2012. http://repository.cmu.edu/theses/28.
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“Hey Neighbor! Let’s Play.” Is a masters thesis evaluating the effects games and playful interactions have in building a sense of community. Throughout the thesis, I researched the emotional connections urban residents have with their communities and neighbors, and used the research data to develop installations for play throughout pedestrian staircases in the Southside Slopes, an urban neighborhood in Pittsburgh. From these installations, I collected user feedback and evaluated how the games affected various residents of the community. From the feedback, I was able to ultimately establish several design principles to inspire and facilitate future designers interested in designing neighborhood-based games.
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Marks, Lori J. ""Let's Celebrate Fall 2000!"." Digital Commons @ East Tennessee State University, 2000. https://dc.etsu.edu/etsu-works/3710.
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Shrestha, Joseph. "Let's Talk About Roads." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/5476.
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Dr. Joseph Shrestha, Assistant Professor, ETSU Department of Engineering Technology shares that U.S. roads received a D-grade in the latest report card from American Society of Civil Engineers (ASCE). His presentation will discuss various aspects of U.S. roads; including funding sources, cost estimation, cost overruns, speed limits, and crash statistics.
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Kaja, Ben. "Let's Waltz the Rumba." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/77489.
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A collection of poems primarily in free verse that deals with loss, love, nostalgia, memory, nature (both human and wild), and the self. The title is a Fats Waller quote I found as the epigraph in one of my favorite books, The World Doesn’t End by Charles Simic. While it is literally impossible to waltz the rumba, since they are two different dances and types of music, I like the idea it provokes for me: it says to me, “let’s do this our own way"? or the old cliché phrase “let’s walk to the beat of a different drummer."? This quote embodies the spirit in which these poems where written.Master of Fine Arts
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Fernandez, Arturo. "Windlife Vs. Let's Read." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1509983717956456.
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Steele, Ann. "Let's talk about psychosis." Thesis, King's College London (University of London), 2014. http://kclpure.kcl.ac.uk/portal/en/theses/lets-talk-about-psychosis(ecbf77f9-57e9-4c31-b454-abe84c01ea96).html.
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Background: Recent advances in the psychological understanding of psychosis are supplementing the traditional medical model approach to schizophrenia. Furthermore, a patient-centred model of care is being introduced throughout healthcare promoting collaborative care inline with patients’ values and preferences. Research suggests that patients with schizophrenia wish to talk about their psychotic symptoms. In contrast psychiatrists may be reluctant to engage in discussion of psychotic symptoms leading to potential difficulties in delivering truly collaborative care. Aims: The current study aims to explore the aspects of psychotic experiences patients wish to discuss in psychiatric consultations, as well as the features on which psychiatrists focus by applying thematic analysis to extracts of naturally occurring, routine outpatient psychiatric consultations between patients with psychosis and their psychiatrists. Results: Sixty-five consultations from a total of 143 contained at least one discussion about a present positive psychotic symptom. Patients with higher clinical levels of positive psychotic symptoms were more likely to discuss psychotic symptoms during the consultation. Both psychiatrists and patients initiated discussions of symptoms, but psychiatrists were more likely to end the discussion. Conclusions: The focus of psychiatrists during discussion of positive psychotic symptoms in consultations does not correspond to the features of psychosis most salient to patients. In order to be more patient-centred the focus and aims of the psychiatric consultation may need to be adjusted to more closely target the concerns of patients.
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Steiger, Sebastian. "Modelling Nano-LEDs." Konstanz Hartung-Gorre, 2009. http://d-nb.info/995394202/04.
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Armelim, Ana Sofia Monteiro. "Experiências com LEDs." Dissertação, Universidade do Porto. Reitoria, 1999. http://hdl.handle.net/10216/10041.
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Armelim, Ana Sofia Monteiro. "Experiências com LEDs." Master's thesis, Universidade do Porto. Reitoria, 1999. http://hdl.handle.net/10216/10041.
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Groves, Teddy. "Let's reappraise Carnapian inductive logic!" Thesis, University of Kent, 2015. https://kar.kent.ac.uk/54023/.
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NASCIMENTO, Jadiel da Silva. "Dispositivo para medição e controle da pressão do balonete das proteses traqueais." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/18945.
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O uso de ventilação artificial é indicado para indivíduos que apresentem, insuficiência ou falência respiratória, traumatismo crânio encefálico ou pacientes politraumatizados. As unidades de terapia intensiva (UTIs) são ambientes destinados ao atendimento de pacientes graves, com potencial risco de morte, que necessitam de atendimento ininterrupto, caracterizadas, muitas vezes, como um ambiente relacionado ao sofrimento e a morte. Sabe-se que nessas unidades é comum encontrar pacientes que necessitam de suporte ventilatório mecânico invasivo através de prótese traqueal. A pesquisa deve como objetivo desenvolver um equipamento específico para aferir e corrigir a pressão do balonete do tubo endotraqueal ou cânula de traqueostomia, e verificar o nível de conhecimento dos profissionais de saúde referente a pressão do balonete externo do tubo ou cânula traqueal. Trata-se de um estudo experimental, realizado no ano de 2015 no laboratório de instrumentação biomédica do Departamento de Engenharia Biomédica da Universidade Federal de Pernambuco (UFPE). O passo inicial para o desenvolvimento do equipamento foi a escolha do sensor de pressão de baixa intensidade, cuja a função primordial do sensor de pressão é transformar uma grandeza fisiológica (pressão) em uma grandeza elétrica (tensão). O equipamento desenvolvido é capaz de monitorar a pressão do cuff, em tempo real e de forma continua. O sistema de alarme sonoro e visual com três LEDs, cada uma com finalidades diferentes, sendo a LED verde responsável em informar que os valores estão dentro dos normais, a LED amarela indica que o valor da pressão se encontra fora dos limites máximo e mínimo estabelecidos como referência e a LED vermelha indicando pressão nula do cuff. O dispositivo criado nesta pesquisa pode monitorar de forma continua a pressão do cuff, e em tempo real sinalizar aos profissionais das UTIs que os valores pressóricos se encontram fora dos limites estabelecidos pelo profissional de saúde. A maioria dos profissionais das duas UTI utilizam técnica de mensuração da pressão do cuff de forma subjetiva com a palpação digital, ao mesmo tempo que realizam o ajuste de forma errada com a utilização da seringa, sem ter a precisão de ter corrigido a pressão para os valores correto
The use of artificial ventilation is indicated for individuals who have, failure or respiratory failure, cranial trauma or polytrauma patients. Intensive care units (ICUs) are environments used in the treatment of critically ill patients with potentially lifethreatening, which require uninterrupted service, characterized often as a related suffering and death environment. It is known that these units is common to find patients requiring invasive mechanical ventilation through tracheal prosthesis. Research should aim to develop specific equipment to measure and correct the pressure of the cuff of the endotracheal tube or tracheostomy tube, and check the level of knowledge of health professionals concerning the external pressure cuff tube or tracheal cannula. This is an experimental study carried out in 2015 in biomedical instrumentation laboratory of the Department of Biomedical Engineering at the Federal University of Pernambuco (UFPE). The initial step in the development of the equipment was the choice of low-level pressure sensor, whose primary function of the pressure sensor is to turn a physiological variable (pressure) into an electrical magnitude (voltage). The equipment developed is able to monitor the cuff pressure in real time and continuously. The audible and visual alarm system with three LEDs, each with different purposes, and the green LED charge to report that the values are within normal, the yellow LED indicates that the pressure value is outside the maximum and minimum limits as a reference and the red LED indicates zero pressure cuff. The device created in this research can monitor continuously the pressure of the cuff, and real-time signal to the ICU professionals that blood pressure values are outside the limits set by health professional. Most practitioners of the two ICUs use cuff pressure measurement technique subjectively by digital palpation while performing adjustment in the wrong way with the use of the syringe without having to precision have fixed pressure for correct values.
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Eckerskog, Sven. "Let's play fair - en jämförelse av Fair Use och svenska undantagsregler applicerat på Let's Play." Thesis, Umeå universitet, Juridiska institutionen, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-138275.
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Olson, Linda Helena. "Masculinities in Bruce Lee's 'Breakthrough' films." Thesis, Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B38778907.
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Wei, Shiyu M. Arch Massachusetts Institute of Technology. "Let's meet at the Civic Center!" Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/97370.
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Thesis: M. Arch., Massachusetts Institute of Technology, Department of Architecture, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (page 129).
The town halt as a type of architecture has become so prevalent that the term has been used to describe the activities that go on inside - namely, social gatherings of the public for purposes of discussion, question, and feedback to the governing body. The archetypes of the town hall, in the 12th century Italy, or 17th century New England, functioned not only as the municipal headquarters with offices and courts, but also in some cases included markets, church, warehouse, museum, pub, etc. Most importantly, it functioned as a meeting place for the public. However, as an architecture typology, the town hall does not scale as the municipality expands. The administrative parts of the town hall can grow or multiply proportionally with the population, but the public functions that were originally embedded in the architecture were either pushed out into the large plaza outside of the city hall, or disappeared entirely. This thesis project seeks to re-establish the ideologies of democracy manifested through the architectural typology of the town hall in New York City's Civic Center through creating small spaces for social discourse.
by Shiyu Wei.
M. Arch.
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Ressler, Christopher Michael. "Let's All Go to the Movies." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/79683.
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Welcome to the movies! Welcome to the stars! Welcome to this grand illusion! All of it's yours.
New Urbanism. Hollywood thinks you're stupid. Scientology. Retro-futurism. Taking back color from toiletries. Personal politics. Cutting off the legs of the bioscopes. The architecture of Fun. The death of Entertainment. Freedom of speech. Sticky floors. Googie. Suburbia. Popcorn. The way we live our lives. All seen through the limelight of a night at the movies.Master of Architecture
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Göhler, Tino. "Lichtauskopplung aus LEDs mittels Metallnanoteilchen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-64116.
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Der externe Wirkungsquerschnitt von auf AlGaAs/InGaAlP basierenden Leuchtdioden (LEDs) ist auf Grund von Totalreflexion infolge des hohen Brechungsindex des Halbleitermaterials (n=3...4) beschränkt. Auf die Oberfläche der LED aufgebrachte metallische Nanoteilchen (MNT) können jedoch als Dipolstreuer genutzt werden, um so die Emission der LED zu vergrößern. In dieser Arbeit wurden zunächst einzelne Goldnanoteilchen verschiedener Größe auf einer solchen Leuchtdiode in zwei verschiedenen Der externe Wirkungsquerschnitt von auf AlGaAs/InGaAlP basierenden Leuchtdioden (LEDs) ist auf Grund von Totalreflexion infolge des hohen Brechungsindex des Halbleitermaterials (n=3...4) beschränkt. Auf die Oberfläche der LED aufgebrachte metallische Nanoteilchen (MNT) können jedoch als Dipolstreuer genutzt werden, um so die Emission der LED zu vergrößern. In dieser Arbeit wurden zunächst einzelne Goldnanoteilchen verschiedener Größe auf einer solchen Leuchtdiode in zwei verschiedenen Umgebungsmedien untersucht. Dabei zeigt sich eine deutliche Verstärkung der Emission, falls die Dipolresonanz des MNT bei kürzeren Wellenlängen im Vergleich zur LED-Emission liegt. Für den Fall, dass die Dipolresonanz mit der Emission überlappt oder bei größeren Wellenlängen liegt, kommt es zu einer Abschwächung. Numerische Berechnungen zeigen, dass dabei die Stärke der Quadrupolmode, welche zusätzliche Absorption hervorruft, sowie eine Rotverschiebung der Dipolresonanz bei Anregung oberhalb des kritischen Winkels der Totalreflexion eine entscheidende Rolle spielen. Mit Hilfe einer speziellen Maskentechnik, der Fischer-Pattern-Nanolithographie, können Arrays von MNT hergestellt und anschließend die MNT in Form und Größe manipuliert werden. Die zunächst dreieckige Form der Partikel führt zu einer Abschwächung der Emission, welche sich aber durch Umwandlung der MNT in Kugeln zu einer Emissionsverstärkung wendet. Dabei kann Licht, welches sonst im Substrat gefangen wäre, durch plasmonische Streuung ausgekoppelt werden. Eine Untersuchung ähnlicher Strukturen auf einem hochbrechenden, transparenten Substrat (GaP) zeigt, dass die Lage der plasmonischen Resonanzen stärker vom Abstand der Partikel abhängt, als gewöhnlich zu erwarten wäreThe external quantum efficiency of light-emitting diodes (LEDs) based on AlGaAs/InGaAlP is limited by total internal reflection because of the high refractive index (typically between 3 and 4) of the semiconductor. Metal nanoparticles (MNP) deposited on the surface of the LED can be used as dipole scatterers in order to enhance the emission of the LED. In this thesis, first, single gold nanoparticles of various sizes deposited on such an LED were investigated. A clear enhancement is detected as long as the dipole plasmon resonance of the particle is at a shorter wavelength than the LED emission. If the plasmon resonance coincides with the LED emission or is at a larger wavelength, the enhancement turns into suppression. Numerical simulations indicate that this latter effect is mainly caused by the particle quadrupole resonance producing extra absorption. Arrays of MNPs can be produced by a special mask technique called \"Fischer pattern nanolithography\" and manipulated in shape and size by additional steps. Originally, the MNPs produced by this technique are triangular in shape and turn out to suppress the LED emission. After transformation of the particles to spheres, a clear enhancement was detected. Light that would otherwise remain trapped inside the substrate is coupled out by resonant plasmonic scattering. Investigations on analogous structures on a transparent high-index material (GaP) indicate a stronger coupling between the particles than expected on the basis of literature data
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Pettersson, Alexander. "Let's Walk, (interaktionsdesign) från början till slut." Thesis, Umeå universitet, Institutionen för datavetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-52936.
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Many interactive products constructed today is not produced towards a specific targetaudience and how they will interact with the product. This master's thesis follows the designprocess in the development of the Let's Walk webapplication. In the designprocess has users of the webapplikation been identified, prototypes developed and an interactive version has been evaluated. The Let's Walk webapplication is a fully working system used to administrate Let's Walk, an exercise competition between companies. Experts and users have been involved to evaluate the Let's walk high-fidelity webapplication prototype. The result of the evaluation shows that involving users and experts in the designprocess is very important when finding usabilityproblems in an interface. It has lead to comments of how to develop future versions of the Let's Walk system.
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Merryfield, Jessica L. "Let's play Designing spaces for cognitive development /." Cincinnati, Ohio : University of Cincinnati, 2006. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1148070735.
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Thesis (Master of Architecture)--University of Cincinnati, 2006.Title from electronic thesis title page (viewedJuly 17, 2006). Includes abstract. Keywords: children's design, architecture, cognitive development. Includes bibliographical references.
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MERRYFIELD, JESSICA L. "LET'S PLAY: DESIGNING SPACES FOR COGNITIVE DEVELOPMENT." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1148070735.
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Coutinho, Ronaldo Portela. "Conversor TrifÃsico com Capacitor Chaveado para LEDs de PotÃncia." Universidade Federal do CearÃ, 2016. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=17634.
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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel SuperiorEste trabalho apresenta o estudo, o projeto e a implementaÃÃo de um driver trifÃsico para diodos emissores de luz (LEDs) baseado num conversor com capacitor chaveado (SC â Switched Capacitor), tambÃm conhecido como charge-pump. Uma luminÃria LED com a tecnologia Chip-on-Board (COB), que proporciona uma elevada densidade de potÃncia, à utilizada como carga. Assim como os LEDs, os drivers destes dispositivos devem apresentar uma longa vida Ãtil e um elevado rendimento. A vida Ãtil dos drivers para LEDs à geralmente limitada pelo uso de capacitores eletrolÃticos convencionais. Estes dispositivos apresentam uma vida Ãtil incompatÃvel com a dos LEDs e, por isso, nÃo devem ser utilizados nos seus drivers. AlÃm disso, os drivers para LEDs devem proporcionar uma baixa ondulaÃÃo de corrente nos LEDs, garantindo um baixo flicker percentual e evitando danos à saÃde humana. Diante destes problemas, o conversor trifÃsico SC proposto nÃo utiliza capacitores eletrolÃticos, o que eleva a expectativa de vida Ãtil do driver. O conversor emite um baixo flicker percentual e à capaz de estabilizar a corrente de saÃda sem a necessidade de um controle de malha fechada, o que pode reduzir os custos de projeto. A topologia permite a dimerizaÃÃo dos LEDs atravÃs da variaÃÃo da frequÃncia de comutaÃÃo. Resultados experimentais de um protÃtipo de 216 W sÃo analisados e discutidos para validaÃÃo da proposta. Em condiÃÃes nominais, o conversor apresentou um rendimento global de 91,5%, um fator de potÃncia acima de 0,99 e uma distorÃÃo harmÃnica menor que 5% nas trÃs fases, obedecendo as Classes A e C da norma IEC 61000-3-2:2014. AlÃm disso, foi obtida uma ondulaÃÃo de corrente de alta frequÃncia igual a 16,97% e um flicker percentual de 4,97%, estando de acordo com as recomendaÃÃes da IEEE. A dimerizaÃÃo dos LEDs permitiu a reduÃÃo da potÃncia de saÃda em atà 50%, com rendimento prÃximo a 91%, fator de potÃncia acima de 0,97, distorÃÃo harmÃnica total inferior a 6% para as trÃs fases e flicker percentual menor que 7% para toda a faixa de potÃncia.
This paper presents the study, design and implementation of a three-phase light-emitting diode (LED) driver based on a switched capacitor (SC) converter, also known as charge-pump. A LED lamp with Chip-On-Board (COB) technology, which provides a high power density, is used as load. As the LEDs, drivers of these devices must have a high efficiency and a long useful lifetime, which is usually limited by the use of conventional electrolytic capacitors. These devices have an incompatible lifetime with LEDs and, therefore, they should not be used in their drivers. In addition, the LED drivers should provide a low ripple current in LEDs, which can provide the emission of a low percent flicker. Studies demonstrate that excessive percent flicker may cause damage to human health. Given these problems, the proposed switched capacitor LED driver does not use electrolytic capacitors, which increases the expectative of useful lifetime of the driver. It emits a low percent flicker, which reduces the risks to human health. It can stabilize the output current without the need of a closed-loop control, which may reduce design costs. It allows the LEDs dimming by varying the switching frequency. An experimental prototype rated at 216 W has been developed in order to evaluate the performance of the proposed approach, while results are properly presented and discussed. In nominal conditions, the drive presented an overall efficiency of 91.5%, a power factor greater than 0.99 and a current total harmonic distortion lower than 5% in three phases. The harmonic currents are in accordance with the limits imposed by IEC Standard 61000-3-2:2014 to class A and C equipment. Furthermore, a high frequency current ripple equal to 16.97% and a percent flicker of 4.97% was obtained, which is in accordance with IEEE recommendations. The LEDs dimming allowed the reduction of the output power up to 50%, while the efficiency remained close to 91% and the power factor remained above 0.97. In addition, the total harmonic distortion was below 6% and the percent flicker was lower than 7% for the entire dimming range.
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Grice, Alan William. "Device physics of conjugated polymer LEDs." Thesis, University of Sheffield, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286975.
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Wood, Vanessa Claire. "All inorganic colloidal quantum dot LEDs." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/40882.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.Includes bibliographical references (p. 85-89).
This thesis presents the first colloidal quantum dot light emitting devices (QD-LEDs) with metal oxide charge transport layers. Colloidally synthesized quantum dots (QDs) have shown promise as the active material in optoelectronic devices because of their tunable, narrow band emission. To date, the most efficient QD-LEDs involve a monolayer of closely packed QDs sandwiched between organic charge transport layers. However, these organic materials are subject to degradation due to atmospheric oxygen and water vapor. In contrast, metal-oxide films used in this work are chemically and morphologically stable in air and can withstand numerous organic solvents, which increases the flexibility of device processing. Furthermore, they can sustain higher carrier injection rates needed to realize an electrically pumped colloidal QD laser. This thesis details the characterization techniques, such as Atomic Force Microscopy, photoluminescence spectroscopy, Hall Effect measurements, X-Ray Diffraction, and Ultraviolet Photoelectron Spectroscopy, used to design efficient QD-LEDs. It reviews the steps used to optimize device performance and obtain a transparent device architecture with external quantum efficiency of 0.15% and a peak luminance of 7000 Cd/m2. This manifests a 100-fold improvement in efficiency over any previously reported all inorganic QD-LED structure.
by Vanessa Claire Wood.
S.M.
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Mars, Risha R. "Organic LEDs for optoelectronic neural networks." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/77537.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 79-81).
In this thesis, I investigate the characteristics of Organic Light Emitting Diodes (OLEDs) and assess their suitability for use in the Compact Optoelectronic Integrated Neural (COIN) coprocessor. The COIN coprocessor, a prototype artificial neural network implemented in hardware, seeks to implement neural network algorithms in native optoelectronic hardware in order to do parallel type processing in a faster and more efficient manner than all-electronic implementations. The feasibility of scaling the network to tens of millions of neurons is the main reason for optoelectronics - they do not suffer from crosstalk and other problems that affect electrical wires when they are densely packed. I measured the optical and electrical characteristics different types of OLEDs, and made calculations based on existing optical equipment to determine the specific characteristics required if OLEDs were to be used in the prototype. The OLEDs were compared to Vertical Cavity Surface Emitting Lasers (VCSELs) to determine the tradeoffs in using one over the other in the prototype neural network.
by Risha R. Mars.
M.Eng.
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Wallace, Michael. "Optoelectronic study of InGaN/GaN LEDs." Thesis, University of Strathclyde, 2016. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27451.
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The quality of light emitting diodes (LEDs) has increased to a point where solid state lighting is becoming fairly common. Despite this, greater understanding of the effect of the device structure and the electric fields within them is helpful to continue improving device efficiency and uniformity and in reducing costs. In this thesis the optical and electronic properties of InGaN/GaN LEDs have been studied with a combination of luminescence spectroscopy, microscopy, conductivity mapping and efficiency measurements. A study was made of the effects of the various electric fields, and the interplay between them, on LED luminescence and conductivity. Cathodoluminescence (CL) mapping shows die to die variation across large wafers revealing the powerful effects of a induced electric field on spectral intensity/position/width, in uncontacted devices. Micron scale spots in the LED material, lower in luminescence intensity and which trap charge, were revealed by CL/EBIC mapping with the origin attributed to cluster point defects in the active region. Depth resolved CL and CL under bias reveal the extent of asymmetry in carrier transport in the p/n type GaN around the active region. LEDs grown with different active region temperature profiles were studied. Devices exposed to high temperature after quantum well growth (2T) were found to have a uniform spatial luminescence and a peak efficiency that is higher and occurs at a lower current density (0.1 W/A @ 1 Acm¯²). By contrast those with a low temperature cap (Q2T) exhibit dark spots in the luminescence, and a lower peak efficiency at a higher current density (0.04 W/A @ 10 Acm¯²). The effect of improvement in LED design and material quality on the device efficiency, uniformity and spectral characteristics was studied. The addition of an Al₀.₂₃Ga.₇₇N electron blocking layer (EBL) was found to reduce the size and strength of the dark spots by about a factor of 2, while an additional In₀.₀₅Ga₀.₉₅N underlayer (UL) removed the dark spots entirely and shifted the luminescence peak by around 100 meV. The effect on the electroluminescence efficiency of the reduction in template dislocation density was found to depend strongly on the drive current density, with defect non-radiative recombination more important at low currents. Overall device efficiency was shown to be improved with an EBL and UL. The most efficient devices were those with the 2T type growth but the relative improvements are larger in LEDs grown with the Q2T method. Together, the results present a number of factors limiting the performance of current LEDs and suggest potential routes for improvement and optimisation.
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Clayton, Govinda. "Let's talk about peace: mediation in civil conflict." Thesis, University of Kent, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.594413.
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This dissertation contributes to the growing literature centered on civil war mediation. Relying on a rationalist framework of conflict and actors, and employing quantitative methods, the research uncovers a number of findings relating to the features that assist and impede civil conflict peace brokers. Paper one demonstrates the importance of the relative belligerent strength. Using disaggregated dyadic data, the analysis shows that insurgents whose capacity more closely matches the state are more likely to see mediation in the first place, and ultimately end their conflict through a settlement This argument is developed in the second paper, which shows how belligerent capacity is affected by natural resources. The presence of oil is shown to increase the relative position of the incumbent, lowering the likelihood of mediation and agreement. Paper three focuses on the interaction between the characteristics of the mediator and the belligerents. It demonstrates that mediation is more likely to be accepted when the incumbent and third party share institutional similarities. Notably, non-democratic states are shown to have a significantly higher demand for mediation led by non-democratic third parties. In paper four, which is co-authored with Kristian :=== Skrede Gleditsch, we extend previous research on mediation by assessing the predictive powers of features highlighted as important determinants for mediation. Our results suggest that a two stage model of mediation and success does relatively well in out-of-sample predictions. In total the dissertation makes a number of important contributions, including: using disaggregated data to facilitate assessments of competing mechanisms; adopting an innovative modelling procedure to better capture the selection effects underpinning mediation; and proposing a new means of result validation that offers a more comprehensive assessment of statistical results. In , ,I I • ( i I-.- -.- "; ~ J.... i ---- ~:= I • this way the dissertation bridges the gap between studies of civil war mediation, and theoretical and methodological innovations within the broader civil war literature.
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Krieger, Angela Kristi. "L'être des lettres : Linda Lê's compositions of form." Thesis, Royal Holloway, University of London, 2010. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538772.
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Since 1987, Linda Lê has composed a corpus (twelve novels, three short-story collections, two compilations of essays, an autobiography) that displays a marked preoccupation with exploring the endless possibilities of literary invention. This interest is manifest most immediately in her fictional depictions of lexically-obsessed protagonists and authors at work and further developed through her creative searching as a reader/writer, which sees her crafting a variety of genres, narratorial configurations, and literary references in her own texts. This thesis addresses the constructive potential of literature figured within Lê's oeuvre by drawing upon the notion of 'l'être des lettres', which expresses the diverse ways in which letters - referring to both a broader literary canon and the solitary activity of reading/writing - contribute to the formulation of Lê's diverse corpus as well as to the elaboration of the literary subject (either Lê as an author or her lexically-obsessed protagonists). The lexical slippage between the terms l'êtrel lettres suggests the transformative possibilities that arise when the subject and the literary converge. 'L'être' will refer to the various modalities of being constructed by and through 'lettres' in Lê's work and that this thesis will examine across three areas: the development of Lê's authorial 'être', or identity, as a result of reading/writing; her thematic representations of the impact of literature upon her protagonists' very being and bodies; and the effects of Lê's preoccupation with the compositional process on the creation, or 'coming to being', of her oeuvre. Departing from the primarily post-colonial and psychoanalytical interpretations of Lê's texts that suggest Lê uses literature to articulate aspects of her own history, this thesis adopts a corpus-based approach to Lê's oeuvre in order to posit reading/writing as a productive force allowing for the composition of separate and distinct literary personae and forms that, beyond her biography, reflect Lê's authorial preoccupations with exploring her craft.
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Boonsin, Rachod. "Développement de luminophores sans terres rares pour l'éclairage éco-énergétique à base de diodes électroluminescentes." Thesis, Clermont-Ferrand 2, 2016. http://www.theses.fr/2016CLF22704/document.
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Les luminaires à LEDs représentent une alternative "verte" aux lampes fluorescentes et aux lampes à incandescence en répondant notamment à des critères de préservation de l'environnement : réduction de la consommation d’énergie, technologies sans mercure ni plomb et recyclables à 98%. Cependant, ces luminophores, qui sont actuellement utilisés dans les luminaires à LEDs, contiennent aujourd’hui des éléments de terres rares qui sont issus à 95% de Chine, créant de ce fait une situation de quasi-monopole et un risque réel pour le déploiement de la technologie LED dans les années à venir. Dans le cadre de cette thèse, nous nous sommes intéressés au développement de luminophores sans terres rares pour produire de la lumière blanche dans les luminaires à LEDs. Au cours de ces travaux nous avons étudié trois types de luminophores sans terres rares: luminophores organiques, luminophores hybrides (organiques-inorganiques) et quantum dots (QDs) type cœur-coquille. Les études optiques réalisées sur ces luminophores sous excitation LEDs UV ou bleue nous ont permis de déterminer leurs caractéristiques colorimétriques (IRC, T(K), PLQY(%)) et de mettre en évidence l’évolution de leurs performances dans les conditions d’usage. Pour obtenir une lumière la plus proche du blanc idéal, les luminophores les plus performants ont été sélectionnés puis mélangés en proportion adéquate avec une matrice polymère de type silicone pour conduire à un film composite offrant une émission blanche de qualité sous excitation LEDs UV ou bleue. Un autre volet de ce travail a été dédié à l’étude de la stabilité de ces luminophores (films ou poudres) en fonction du temps et de la température. L’influence de ces paramètres sur les propriétés optiques a été déterminée. Des performances optiques de 30% ont été enregistrées avec des caractéristiques photométriques intéressantes. Aussi, l’ensemble des résultats obtenus montre l’intérêt de poursuivre ces études sur les luminophores sans terres rares qui offrent des propriétés optiques intéressantes. Même s'ils ne concurrencent pas encore les luminophores inorganiques pour l’application « éclairage grand public », les luminophores sans terres rares peuvent déjà se positionner sur d’autres secteurs d’activité comme par exemple : l’éclairage d’ambiance, la signalétique le marquage anti-contrefaçonsLighting technologies based on light-emitting diodes have become an alternative solution over the obsolete technologies (fluorescent lamps and incandescent lamps) due to their positive key criteria of environmental conservation: reduction of energy consumption and mercury/lead-free with 98% recycling technologies. However, the rare-earth elements, which are currently used in LED lightings, are produced by China at about 95%, thereby creating a monopoly situation on the rare-earth elements’ market and also a risk to the deployment of LED technologies in coming years. In this work, we have been interested in the development of rare-earth-free luminescent materials for LED lighting applications in order to produce a white light emission. Three kinds of rare-earth-free luminescent materials have been investigated: organic phosphors, hybrid (organic-inorganic) phosphors and core-shell quantum dots (QDs). The optical studies of these phosphors recorded upon UV and/or blue excitations allow us to determine their colorimetric parameters (CRI, T(K), PLQY(%)) and to demonstrate their optical performances for use in lighting devices. In order to yield a color emission close to ideal white light, the best phosphors were selected and then introduced by mixing them in appropriate proportions into silicone polymers. Another part of this work was devoted to the studies of stability of phosphors (films or powders) under operating conditions of LEDs, moreover, variation of their optical properties as a function of time and temperature were also determined. The optical performances about 30% have been recorded with some interesting colorimetric parameters. Although these materials have presented lower photoluminescence properties compared with commercial rare-earth based inorganic phosphors for “public lighting” applications, they can already be positioned on other luminescent sectors such as indoor lighting, signage anti-counterfeit marking
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Merz, Andreas [Verfasser]. "Mikrowellen-Spinmanipulation in Spin-LEDs / Andreas Merz." Aachen : Shaker, 2015. http://d-nb.info/1071527959/34.
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Hansson, Josefin, and Magnus Mets. "Hur leds den inhyrda personalen i kundföretaget?" Thesis, Högskolan i Gävle, Avdelningen för ekonomi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-14576.
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Syfte: Vi vill med denna undersökning se hur cheferna leder sin inhyrda personal när arbetsgruppen består av både inhyrd och ordinarie personal. För att få svar på detta har vi utgått från fyra frågeställningar Hur ser introduktions- och utbildningsinsatserna ut för de inhyrda? Anpassar ledarna sitt ledarskap gentemot de inhyrda? Hur motiveras de inhyrda? Hur gör ledarna för att få de inhyrda att känna sig delaktiga i organisationen? Metod: Vi har använt en kvalitativ metod. Våra primärdata är intervjuer av ledare. Sekundärdata är insamlade med hjälp av facklitteratur och vetenskapliga artiklar. Därefter har vi låtit den teori vi valt ut möta den empiri vi fått fram. Resultat & slutsats: Ledarna på de företag vi undersökte ansåg att de inte anpassar sitt ledarskap gentemot den inhyrda personalen. De inhyrda får samma introduktion och motiveras på samma sätt som den ordinarie personalen. Utifrån de forskningsresultat vi tagit del av så anser vi att en viss anpassning bör ske, framförallt vid introduktion av den inhyrda personalen. Förslag till fortsatt forskning: Hur pass lång bör kontrakttiden vara eller hur pass avancerade bör arbetsuppgifterna vara för att det ska bli lönsamt med en anpassad introduktion för inhyrd personal? Uppsatsens bidrag: Denna studie visar hur ledarna i de arbetsgrupper vi undersökt leder de inhyrda. Även om man inte kan generalisera utifrån denna forskning anser vi att det går att se en tendens då ledarnas svar ofta överensstämmer.Aim: We want to use this study to investigate whether the leaders of the companies we studied lead the hired workers in a different way when the working group includes both hired and ordinary staff. To answer this we have been based on four issues: What do the introductions- and training efforts look like for the hired worker? Do the leaders adapt their leadership towards the hired worker? How do they motivate the hired worker? How do the leaders get the hired worker to feel involved in the organization? Method: We have chosen a qualitative method. Our primary data are collected by interviews of leaders. Secondary data are collected with the help of literature and scientific articles. Then we have allowed the theory we have selected to meet the empirical knowledge gained. Result & Conclusions: In our study, we concluded that the leaders of the companies we surveyed consider that they don’t adapt their leadership towards the hired workers. The hired workers got the same introduction and get motivated in the same way. From research we have studied, we believe that some adjustment should be made, especially regarding the introduction of the hired worker. Suggestions for future research: How long should the contract term be or how advanced tasks should it be to make it profitable with a customized introduction for hired workers? Contribution of the thesis: This study shows how the leaders of the groups we studied control the hired worker. Even though we cannot generalize based on this research we believe that we can see a trend since the leaders' responses often coincide.
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Dudda, Bruna. "Morphology of leds by atomic force microscopy." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/6647/.
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The concern of this work is to present the characterization of blue emitting GaN-based LED structures by means of Atomic Force Microscopy. Here we show a comparison among the samples with different dislocation densities, in order to understand how the dislocations can affect the surface morphology. First of all we have described the current state of art of the LEDs in the present market. Thereafterwards we have mentioned in detail about the growth technique of LED structures and the methodology of the characterization employed in our thesis. Finally, we have presented the details of the results obtained on our samples studied, followed by discussions and conclusions.
L'obiettivo di questa tesi é quello di presentare la caratterizzazione mediante Microscopia a Forza Atomica di strutture di LED a emissione di luce blu a base di nitruro di gallio (GaN). Viene presentato un confronto tra campioni con differente densità di dislocazioni, allo scopo di comprendere in che modo la presenza di dislocazioni influisce sulla morfologia della superficie. Innanzitutto, viene descritto il presente stato dell'arte dei LED. Successivamente, sono forniti i dettagli riguardanti la tecnica di crescita delle strutture dei LED e il metodo di caratterizzazione adottato. Infine, vengono mostrati e discussi i risultati ottenuti dallo studio dei campioni, seguiti dalle conclusioni.
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De, Mello John Christian. "Ionic space-charge effects in polymer LEDs." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.625051.
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Gutha, Akash. "QUANTUM KEY DISTRIBUTION USING FPGAS AND LEDS." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587769155531749.
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Gallardo, D. E. "Dynamic effects in CdTe quantum-dot LEDs." Thesis, Cranfield University, 2006. http://dspace.lib.cranfield.ac.uk/handle/1826/2961.
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In this work the electrical and electroluminescence properties CdTe nanocrystal films were analysed. The structure consisted of a multilayer of CdTe nanocrystals deposited by the layer-by-layer technique, sandwiched between an ITO anode and an aluminium cathode. The first part of this work was dedicated to structural and process improvement. Earlier devices, produced through a layer-by-layer (LbL) manual procedure, had an average thickness of 30nm per nanocrystal monolayer, with a roughness near 30% of the overall thickness. Electrical tests showed current densities over 100 mA/cm^2, with a frequent occurrence of pinholes and short-circuits that caused erratic sample behaviour and device rupture. SEM and AFM microscopic analysis showed that the nanoparticles were aggregated in 15-20nm thick clusters bound by polymer. A high porosity and non- uniformity of the multilayer was observed, explaining the formation of short-circuits. Luminescence was obtained from a very small number of samples, and with a very short duration that did not make spectral analyses possible. A robotic arm was programmed to carry out the LbL deposition, in an attempt to reduce the inhomogeneities of the multilayer. A key factor was the introduction of a special routine to remove the samples from the solutions. The sample withdrawal was designed to be in the vertical at a rate of 1.18 mm/s. The idea was to use gravity and the surface tension of the aqueous solutions to remove all the excess liquid from the surface. Additionally, poly(ethylenimine) (PEI) was eliminated from the process to improve homogeneity. These modifications produced multilayers with a thickness of 3nm per layer, average roughness below 5nm and CdTe packing density of 27%. Electrical measurements showed a stabilisation of the current-voltage (I-V) characteristics. A significant improvement in luminescence occurrence frequency and intensity was also achieved, enabling first spectral analyses. Once a reliable manufacturing procedure was developed, the electrical characterisation commenced with the analyses of samples with a different number of layers, operated in air. A field dependency of the I-V curves was found. Optimal performance was obtained from 30-layer samples, and this number of layers was adopted for subsequent analyses. Best samples showed external quantum efficiencies of 0.51%, with a photometric response of 0.8 lm/W and peak brightness of 1.42 cd/m^2. However, current and electroluminescence (EL) degradation with voltage and operation time were found in the device. Single carrier devices revealed a barrier for electron injection higher than predicted by the band diagram of the structure. The presence of an aluminium oxide layer at the multilayer/cathode interface was postulated, and confirmed through experiments in nitrogen. It was proposed that the growth of this oxide layer is the cause of device degradation during operation in air. However, it was demonstrated that the presence of the oxide favoured radiative recombination prior to degradation, with device efficiencies nearly 10 times higher than in devices without the oxide film. This was justified through three effects: charge accumulation at both sides of the oxide, field concentration across the oxide barrier and a reduction in leakage current. Unequal behaviour of samples with different electrode materials revealed that charge injection was the limiting mechanism for current flow, with a current onset field in the range of 2-3x10^7 V/m. Fowler-Nordheim plots showed that field emission was responsible for hole and electron injection into the device. Also, Fowler-Nordheim plots provided evidence of the dynamic nature of the cathode oxidation process. Dielectric breakdown of the aluminium oxide barrier at a rupture field of 3x10^7 V/m was found as a possible triggering mechanism of oxide layer growth. It was found that a critical field around 4.5x10^7 V/m caused irreversible loss of photoluminescence (PL) of the nanocrystals. This loss was attributed to an avalanche effect within the multilayer. The operational range for the devices is then found to be between 2x10^7 V/m and 4.5x10^7 V/m.
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McNamara, Kathleen Anne. "Let's Talk About It, a group for adolescent girls." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ32941.pdf.
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Trip, Albert. "Statistical Process Control in practice let's make it better /." Amsterdam : Amsterdam : Faculteit der Natuurwetenschappen, Wiskunde en Informatica ; Universiteit van Amsterdam [Host], 2000. http://dare.uva.nl/document/57156.
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Lam, Yat-lim, and 林逸濂. "The society of Hong Kong in Lilian Lee's fiction =." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43208629.
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Quigley, Jennifer. "Let's work| Employment experiences of adults with developmental disabilities." Thesis, California State University, Long Beach, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1569589.
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The present study investigated the employment experiences of adults with mild developmental disabilities. The study's sample consisted of 45 participants with developmental disabilities who were over the age of 18. Participants were recruited from two Regional Centers in Southern California and either phone interviews or in-person interviews were conducted.
A structured interview protocol examined each participant's current work experience, along with several items exploring facilitators and obstacles to employment. Data from this qualitative investigation were organized into categories using inductive content analysis. Descriptive statistics were computed for quantitative items. Overall, it was discovered that: participants found money as the most rewarding aspect of employment, relied on outside support in obtaining and maintaining employment and found few obstacles of which to overcome, worked with others with developmental disabilities, and utilized workplace supports in entry level positions making an average wage of $8.92 a hour during a 20.72 hour work week.
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Shephard, Thomas F. "An LEA's financial devolution pilot scheme : one school's involvement." Thesis, University of East Anglia, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235580.
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Taylor, Andrew R. "Let's Talk about It| Collective Rumination's Effect on Aggression." Thesis, California State University, Long Beach, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10840250.
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Rumination is defined as thinking about a provoking event. Previous studies had participants ruminate by themselves (i.e., engage in individual rumination), however, individuals can also experience rumination if they communally relive a provocation with others. We have termed this phenomenon “collective rumination. Participants (n = 175) first completed the Revenge Planning subscale of the Displaced Aggression Questionnaire. They were then provoked, randomly assigned to either the collective rumination, individual rumination, or distraction condition, and given the opportunity to aggress. Results indicated that collective rumination produced significantly higher amounts of aggression relative to both individual rumination and distraction. This effect, however, was moderated by revenge planning. Specifically, collective rumination increased aggression for participants with low and mean levels of revenge planning but did not impact aggression for those high in revenge planning. Furthermore, there was a strong positive correlation between group cohesion and aggression for participants who collectively ruminate.
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Gan, Min. "The phantom returns: on Lilian Lee's three supernatural stories." Thesis, University of Iowa, 2010. https://ir.uiowa.edu/etd/804.
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This thesis, based on Green Snake, The Reincarnation of Golden Lotus and Rouge, three novels written by Hong Kong author Lilian Lee, discusses the respective supernatural heroines in relation to the Chinese folklore and to the Hong Kong status quo before the 1997 Handover, seeking to find the allegorical significance behind the heroines beyond the genre of fantastic.