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Exploring child-led research : case studies from Bangladesh, Lebanon and JordanCuevas-Parra, Patricio January 2018 (has links)
The right to participate and express a view is an intrinsic right afforded to all human beings, regardless of age (Lundy, 2007). Explicitly, Articles 12, 13, 14 and 15 of the United Nations Convention on the Rights of the Child (UNCRC) grant participatory rights to children and young people in decision-making. One of the forms of participation academics and practitioners have studied over the past decades, the engagement of children and young people in participatory processes, is moving away from the understanding of children as passive recipients of research to active participants. However, literature has paid scant attention to research led directly by children and young people (Thomas, 2015). Child-led research is understood, as starting definition from literature, as an approach in which children and young people are involved in all stages - from planning, fieldwork and analysis to dissemination. The aim of this research is to critically explore how the process and outcomes of children and young people's participation in their own child-led research contributes, positively or negatively, to decision-making processes in the context of international development programmes. The research questions are: Question 1: What are children and young people's motivations for, expectations of and experiences with engaging in their own child-led research as a way to influence decision-making? Question 2: What are the processes of child-led research that positively or negatively influence decision-making? Question 3: In what ways does child-led research influence decision-making? (And why and how do they do so?) This research project used a case study approach to examine two cases where children and young people claimed they conducted child-led research. The first, Bekaa and Irbid, investigated the research conducted by a group of children and young people on issues relevant to their situations as refugees in the host countries of Lebanon and Jordan. The second, Dhaka, reviewed child-led research focused on the lack of birth certificates issued for Bangladeshi children and the possible effects of not having this legal registration. A group of children and young people who are members of a Children's Parliament in Dhaka led this project. The research participants for this project are defined as (1) the children and young people, aged 12 to 18 (when I interviewed them), who are associated with World Vision programmes and engaged in the child-led research projects within their constituencies in the Irbid and Bekaa and Dhaka case studies and (2) the adult professionals who acted as facilitators of child-led research projects and those who worked in the design of these projects or dissemination of their findings. These participants were those who were best suited to provide the information needed as they were fully involved in the child-led research projects and had in-depth knowledge to contribute answers to the research questions. This project adopted several methods for data collection, including focus groups, semi-structured interviews, observations and documentary review. The study followed ethical research guidelines to ensure the safety, rights, dignity and well-being of both the children and young people and adult participants (Morrow, 2009). The research took into account the special considerations required to gain informed consent, ensure confidentiality and anonymity, acknowledge the cultures of the research sites, and refrain from presenting information that may potentially harm participants (Marshall and Rossman, 2006). The findings of the study show that the child-led research approach is considered an adequate participatory approach that creates spaces for children and young people to engage in their own research and influence change based on their findings. Thus, this approach enabled participants to gather together and pursue collectively a research project in which they were able to explore issues about their lives using research methodologies that were appropriate to their experiences, abilities and expertise. This conversion, however, highlights a variety of tensions around the understanding and legitimacy of child-led research. Findings from this study supports the view that child-led research generates empirically grounded knowledge, which produced through data collection and personal experiences of the young researches and its analysis as a whole. Findings also reveal that the young researchers' motivations and expectations were to make an impact on their own lives, as well as the lives of their peers and change a situation that they perceived as unfair. Findings show that the adult facilitators played an important role in facilitating the young researchers but not managing them. However, this study evidenced some tensions between participation and protection rights. The study found manifestations of power amongst the children and young people during the child-led research projects, which were based on age, gender, religion, language and ethnicity. This confirms children and young people can replicate power relations within their participatory projects, which are deeply embedded in their traditions and cultures. Findings show that child-led research has different levels of impact; on decision-making and in the individual lives of the young researchers. This is connected to the contexts where children and young people conducted their research, which was conducive in one case study and more challenging in the other case. Overall, the findings of this study contribute to the body of literature that challenges the dominant conceptualisation that children and young people are unable to conduct their own research. Instead, the findings of this research project contribute to the study of children and young people's participation by providing different perspectives on the debate around the children and young people's abilities and motivations to engage in their own child-led research projects. The findings contribute to knowledge about the nature of child-led research as an approach that supports children and young people in their struggle to participate in society. These findings contribute to the substantial gap of understanding about what is knowledge and expertise by exploring the ways in which children and young people conduct their own research and create knowledge with the aim of making a change in society. Specifically, the findings provide empirical evidence of the impact that their work has had on policy and practice and their personal lives.
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Managing the tensions between the maintenance of academic standards and the commercial imperative : a case study in UK higher educationPitcher, Graham January 2011 (has links)
During the past two decades there have been significant changes in the landscape for higher education. Among these was a trend for universities and colleges to respond by adopting a more market-driven approach, leading to the introduction of new public management within universities and colleges, which led to the emergence of tensions between the academic and quasi business aims. In 2004 the UK government changed the criteria for the grant of degree-awarding powers and university title opening up the possibility for non-public organisations to apply. This thesis presents the case study of a private sector for-profit organisation as it introduced a more robust quality assurance infrastructure during the application process for taught degree-awarding powers. The analysis is undertaken within a conceptual framework developed from institutional and agency theory. The need to demonstrate legitimacy and the influence of key groups played a large part in the changes made. Using data collected via participant observation, key informant interviews and documentary evidence, the study examines the changes and management actions that took place during the period between June 2004 and July 2009 in order to identify the strategies that were adopted to manage the tensions between the academic standards and the commercial imperative of meeting shareholder expectations. The study contributes to the literature covering change in educational institutions and in particular that which reports on the introduction of a more business-oriented approach to the management of universities. The study is able to bring a new perspective to studying the management of tensions between academic and business aims by looking at the issues from an alternative angle. The key strategy developed was a gradual rationalisation of the academic aims within the business aims such that the duality of aims was diminished.
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Dispositivo de tecnologia assistiva baseado no processamento em tempo real de imagens do globo ocularFigueiredo Vieira, Tiago 31 January 2009 (has links)
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Previous issue date: 2009 / Nesta dissertação são investigadas algumas técnicas de rastreamento ocular para o
desenvolvimento de um dispositivo de tecnologia assistiva simples e de baixo custo, para
indivíduos com deficiências motoras severas. O dispositivo desenvolvido permite que o
usuário controle a posição de um cursor em uma tela gráfica e acione programas de
computador com seus movimentos oculares. Dessa forma, os indivíduos vítimas de
doenças degenerativas do sistema nervoso ou de acidentes vasculares cerebrais, com pouca
ou nenhuma liberdade de movimento dos membros e/ou da cabeça, podem exercer alguma
atuação no mundo à sua volta se comunicando com outras pessoas. Os sistemas
desenvolvidos utilizam webcams de baixo custo e iluminação do objeto com LEDs
infravermelhos. Algumas técnicas de detecção de formas e de calibração de câmeras foram
investigadas para localização, em tempo real, da pupila do globo ocular de um indivíduo.
Os algoritmos de processamento de imagens desenvolvidos para funcionamento da
interface foram implementados inicialmente em Matlab® e posteriormente em C. Este
último forneceu um ganho substancial em velocidade de processamento. Foi desenvolvida
uma primeira configuração de dispositivo de tecnologia assistiva, em formato de armação
de óculos, que funciona sem necessidade de re-calibração, desde que o usuário permaneça
com a cabeça imóvel. São também descritos resultados preliminares obtidos no âmbito de
desenvolvimento de uma segunda configuração de dispositivo, para uso remoto, que
permite rastrear os movimentos oculares independentemente dos movimentos da cabeça do
indivíduo
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Enhancing fluorescence and charge transport in disordered organic semiconductorsThomas, Tudor Huw January 2018 (has links)
High performance optoelectronic applications require simultaneously high mobility ($\mu$) and high quantum efficiency of fluorescence ($\Phi$). While this has been realised for organic small molecule semiconductors, applications such as high efficiency organic photovoltaics and bright organic light-emitting diodes towards electrically driven lasing are hampered by an apparent trade-off between $\mu$ and $\Phi$ in disordered systems. Recent reports of state-of-the-art device performance often optimise $\mu$ and $\Phi$ in disordered organic materials separately, and employ multi-layer architectures. In this work, we investigate materials in a class of donor-acceptor polymer materials; the indacenodithiophene-$\textit{alt}$-benzothiadiazole family, which demonstrate high $\mu$ in spite of a low long-range structural order, to understand the interplay between these two important device figures-of-merit. In the first section, we evaluate the effect of various tuneable parameters on $\mu$ and device performance in organic field-effect transistors. Using chemical modifications to the solubilising side chains, we observe that the substitution of bulky groups leads to a reduction of the hole mobility $\mu_h$ > 2 cm$^{2}$/Vs to ~ 0.5 cm$^{2}$/Vs in the benchmark polymer of this family, indacenodithiophene-$\textit{alt}$-benzothiadiazole. Crystallographic and exciton-quenching based experiments confirm this observation is closely related to the degree of polymer backbone aggregation, and this leads to a different temperature evolution of the transport behaviour. In order to reliably improve $\mu$ in these systems, an elongation of the donor subunit is required. This increases the $\pi$-electron density on the donor, and can lead to an improvement in $\mu$ where the side chain density is decreasing. This chemical design, leading to a more highly aggregated structural motif is much more potent in determining $\mu$, it seems, than design strategies to further improve the energetic disorder in the joint density of states and the potential barrier to torsion, which may be near optimised in these low-disorder systems. In the second section, we unpick the precise relationship between the degree of aggregation apparently linking high $\mu$ to low $\Phi$. With a prototype system, we compare the photophysics of two indacenodithiophene-$\textit{alt}$-benzothiadiazole polymers differing by side chain bulkiness. Despite the aforementioned suppression of $\mu$, we observe an improvement to $\Phi$ of $< 0.02$ to $\sim 0.18$ upon backbone separation. This derivative has the highest $\Phi$ reported for any polymer with $\mu$ exceeding that of amorphous-Si. However, the $\Phi$ in the more aggregated derivative is not limited by the formation of non-emissive excitons, but rather by an additional internal conversion pathway which is strongly temperature dependent, and mediated by Raman-active vibrations and close chain coupling. Extending this study, we analyse additional materials in this family with the highest $\Phi \cdot \mu$ values reported for conjugated polymers. We find that increasing the energy gap leads to an increase in $\Phi$, and secondary emission pathways via weakly luminescent inter-chain charge transfer species. By solving the rate equations for exciton recombination, we use the radiative rate of inter-chain luminescence as a probe to show strong wavefunction mixing at close-contact points for some polymers, and suggest this as the origin for a superior $\mu$ in dithiopheneindenofluorene-$\textit{alt}$-benzothiadiazole compared to indacenodithiophene-$\textit{alt}$-benzothiadiazole. We demonstrate how low $\mu$ can be decoupled from the energy gap ($E_g$), and propose backbone elongation leading to increased inter-chain wavefunction overlap and a higher $E_g$ as a design rule to increase $\Phi$ and $\mu$ together. Finally, we assess the role of low-frequency vibrations in organic semiconductors displaying thermally activated delayed fluorescence (TADF). In the low-aggregation limit where $\Phi$ is maximised, we show that non-radiative triplet recombination is strongly related to low frequency torsional motion, and both are reduced in the presence of a rigid polymer host matrix for various TADF materials across different classes. However, we also explore the importance of rotational freedom in determining the oscillator strength, exchange energy, and spin-orbit coupling matrix elements which mediate luminescence in the absence of a rigid host. We demonstrate that suppressing dynamic motion is a powerful tool to modulate the photophysical properties of these emitters, and can lead to improved $\Phi$ particularly for low $E_g$ emitters.
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Architectural emptiness : on a reinterpretation of the architectural implications of Heidegger's concept of dwellingWilliams, Aidan January 2013 (has links)
This thesis reinterprets the architectural implications of Heidegger’s concept of dwelling. In particular it stresses the importance of the concept of poetry on dwelling that was outlined in ‘ ... Poetically Man Dwells ... ’. This essay from Heidegger’s late period has been less frequently quoted in the literature of the architectural profession than some of Heidegger’s more well known essays. The importance of poetry is developed in this thesis through creative practice explorations of Heidegger’s philosophy supplemented by deep textual analysis. By developing Heidegger’s concept of poetic dwelling, it is possible to reinterpret his ideas about building in richer ways than have previously been carried out in architecture. We will discover that space has a particular kind of emptiness that allows for poetic experience. Ways of building that manifest this emptiness can be considered building for dwelling. The focus on poetic dwelling unravels previous architectural interpretations of Heidegger’s concept of dwelling. These interpretations tend to focus on the creation of a certain type of product rather than on enabling the poetic dwelling process. Consequently, by shifting this understanding of dwelling new links can be suggested to the work of architectural writers and practitioners who hitherto have not been considered to be Heideggerian.
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Prototyping the exhibition : a practice-led investigation into the framing and communication of design as a process of innovationBletcher, Joanna January 2016 (has links)
A challenge ignited the research outlined in this thesis. Design is increasingly being framed (across academia and industry) as an integral method and strategy for social, cultural and economic innovation. How is this value to be communicated within the museum context, which is more commonly rooted in an object-centric tradition? Temporary exhibitions are a primary means of communication and engagement for museums. The presentation of contemporary design has followed traditions of display stemming from fine art practices, as well being influenced by those in commercial environments. Consequently the thesis argues that there is a prevailing tendency to display the outcomes of design activity, to celebrate aesthetics and functionality, and to concentrate on the personality and talent of the designer. A key concern underpinning this research is that many museum design exhibitions arguably struggle to reveal the complexity of design activity: the intellectual and material processes driving innovation. This arguably risks limiting broader interpretation, and stifles the opportunity to extend audience understanding of design. The aim of this thesis is to question and explore key concepts that constitute the communication and exhibition of design in the museum. Design, innovation, curating, exhibition, audience: in the dynamic, transitioning contexts of design and the museum, all concepts must be scrutinized. In order to navigate this territory, a core method of design inquiry is adopted: prototyping. In this research, prototyping actively puts concepts to work through a dialectical investigation. This involves actively engaging in design to examine the concepts of curatorial practice, the exhibition, and innovation, whilst concurrently exploring concepts of design and innovation through the process of curating exhibitions. This dual-focussed research approach that has been developed, can be described as a hermeneutic, practice-led methodology. Hermeneutics supports a belief in contextually situated, practical action as a basis for developing understanding and knowledge (Bolt, 2011; Heidegger, 1962). The method of exhibition-making is framed and employed as a practical prototyping process: curating exhibitions in order to reflect on the construction of design narratives from within. Prototyping becomes a way to reflexively explore, analyse and question the practice of framing, mediating and communicating design as innovation. Three iterative practical projects act as case studies for the thesis, situated in three concrete contexts: the industry sponsor – V&A Museum of Design Dundee; design in Higher Education; and a national innovation festival. Each can be seen as the exploration and delineation of a design space (Heape, 2007), with all three forming part of the wider design space that is the thesis as a whole. Through reflecting on the acts of evaluating, selecting, editing, juxtaposing, connecting, framing and presenting design practice through exhibition, the research has formulated a curatorial strategy that aims at attending to the complex nature, changing priorities and values of particular design contexts. The thesis names this approach ‘the constellation’: adapting this term from the work of critical theorist Theodor Adorno (1973). The constellation takes the form of a series of visualisations that draw on, combine and develop research on design theory, design processes, and prototyping, by a number of key design researchers (e.g. Buchanan, 1998, 1995a; Dorst, 2015a, 2008; Heape, 2007; Lim et al., 2008; Sanders and Stappers, 2014, 2008). Operating at two levels, the constellation is the manifestation of the reflexive research process, illuminating both design and curatorial practice. It makes an original contribution to knowledge in two ways: firstly as the visual delineation of a prototype curatorial strategy for researching, framing and communicating narratives of design; secondly it offers a conceptualisation of concept development in design practice, shown as the continuous exploration of a design space. This articulates how prototyping, as a key design method, can encourage innovation through the exploration and analysis of concepts at varying levels of detail, with the aim of developing new perspectives. This thesis also makes an original contribution on a methodological level by extending the practice and discourse of prototyping to the method of exhibition, framing it as a strategy for innovation in design research. This adds to current discourse surrounding practice-led research within art and design. It also contributes to nascent discourse in relation to curatorial practice for design, and the growing interest in the specificities of design curation, in the context of the museum.
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Output limitations to single stage and cascaded 2-2.5μm light emitting diodesHudson, Andrew Ian 01 December 2014 (has links)
Since the advent of precise semiconductor engineering techniques in the 1960s, considerable effort has been devoted both in academia and private industry to the fabrication and testing of complex structures. In addition to other techniques, molecular beam epitaxy (MBE) has made it possible to create devices with single mono-layer accuracy. This facilitates the design of precise band structures and the selection of specific spectroscopic properties for light source materials.
The applications of such engineered structures have made solid state devices common commercial quantities. These applications include solid state lasers, light emitting diodes and light sensors. Band gap engineering has been used to design emitters for many wavelength bands, including the short wavelength (SWIR) infrared region which ranges from 1.5 to 2.5 μm [1]. Practical devices include sensors operating in the 2-2.5 μm range. When designing such a device, necessary concerns include the required bias voltage, operating current, input impedance and especially for emitters, the wall-plug efficiency. Three types of engineered structures are considered in this thesis. These include GaInAsSb quaternary alloy bulk active regions, GaInAsSb multiple quantum well devices (MQW) and GaInAsSb cascaded light emitting diodes.
The three structures are evaluated according to specific standards applied to emitters of infrared light. The spectral profiles are obtained with photo or electro-luminescence, for the purpose of locating the peak emission wavelength. The peak wavelength for these specimens is in the 2.2-2.5μm window. The emission efficiency is determined by employing three empirical techniques: current/voltage (IV), radiance/current (LI), and carrier lifetime measurements. The first verifies that the structure has the correct electrical properties, by measuring among other parameters the activation voltage. The second is used to determine the energy efficiency of the device, including the wall-plug and quantum efficiencies. The last provides estimates of the relative magnitude of the Shockley Read Hall, radiative and Auger coefficients. These constants illustrate the overall radiative efficiency of the material, by noting comparisons between radiative and non-radiative recombination rates.
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Aktivitet och ljusOlsson, Anna January 2009 (has links)
<p>Abstract</p><p>Den här uppsatsen beskriver examensarbetet Ljus och aktivitet. Syftet med projektet har varit att ifrågasätta invanda tankemönster och förhållningssätt och på så sätt hitta nya och relevanta lösningar för en traditionell armatur. Uppsatsen beskriver ljuset kopplat till aktivitet ur användarnas perspektiv, hur de upplever ljuset kopplat till deras hem och hur de använder sina rum. Ljuset beskrivs även utifrån ett historiskt, socialt, emotionellt och biologiskt perspektiv men också hur ljuset skapar rumslighet genom kontraster. Upplevelsen av det naturliga ljusets variationer finns som en underliggande ton i arbetet. Utvecklingen av LED - tekniken skapar nya möjligheter och det här arbetet är ett försök att genom LED – tekniken hitta nya lösningar till en traditionell produkt. Uppsatsen är också ett försök att beskriva designprocessen, de verktyg jag använt t ex ITK och introspektion mm. Vad jag kommit fram till och resultatet, men också hur jag ser på min roll som designer. Resultatet är en flytt- och bärbar armatur där ljuset regleras vid närvaro i rummet, men också manuellt efter aktivitet och situation.</p><p> </p>
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Degradation Analysis of High Power LED Device in High Temperature Acceleration Aging TestLin, Yu-kuan 07 September 2007 (has links)
Recently, the high-power light-emitting diodes (LEDs) have been used from the traditional indicator purpose to general illumination purpose. The operating environment and requirement has been more severe. The long operating life high efficiency and high reliability are its main feature attracting the lighting community to this technology.
The effect of operating temperature on the degradations of high-power blue LEDs is studied in this thesis. The experiment, measurements, and finite element simulations were conducted to investigate the possible causes of LED degradation. The influence of LED material degeneration on the radiometric pattern was analyzed by tracing rays simulation.
Different groups of sample LEDs produced by Lumileds, Unity opto technology Co., and Everlight electronics Co. were studied. Different operating ambient temperatures, e.g. 80oC, 100 oC, and 120 oC, were considered in the accelerated aging test. Experimental results indicated that yellowing, carbonization, gel degeneration, lens chapping and deformation were observed during the test. Results also indicated that the operating temperature is the key factor for LED failure mechanism, that is, different operating ambient temperature may lead to different degradation phenomenon.
Numerical simulation results shown that the creep caused by high temperature and thermal stress would cause solder takeoff. This takeoff defects were observed in experimental results. Through ray tracing simulation, it is assured that gel degeneration would change the radiometric pattern of the LED significantly.
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High School Principals' Perceptions of Their Effectiveness in Leading District Initiated High School Reform: An Analysis of High School Principals Previously Engaged in High School Reform in an Urban Texas School DistrictRios, Carlos 2012 May 1900 (has links)
Current research has described a changed central office perspective that not only includes campus principals as part of the district's leadership team, but also focuses on developing principals' instructional abilities with the purpose of supporting school reform. However, to date, research has not provided examples of a successful relationship between campus principals as a collective group and the district (central office) leadership team attempting to implement district-wide high school reform.
This study was conducted in order to examine the perceptions of high school principals (in an urban school district in Texas) toward district-wide initiated high school reform. Methods used for data collection included semi-structured interviews, review of available artifacts, and case profile development. Questions derived from the researcher's review of the literature and ongoing professional interest were the basis for dialogue during the semi-structured interviews. All interviews were recorded, transcribed, and unitized. The data were further organized into categories and
subcategories.
The analysis of principals' perceptions provided insight and helped develop an understanding of obstacles that high school principals perceive in implementing district-led high school reform. This study has concluded that the district goals and mission do not define the daily operations of a campus. Instead, the district goals and mission are often reprioritized because principals are insecure, believe they have a better understanding of the local context than does the central office, and are oftentimes frustrated by the central office's political machinations.
Recommendations include suggestions on how to eliminate these obstacles, improve the ability of principals to implement district-led high school reform, and how to suggest actions for the improvement of the high school reform process at the central office level.
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