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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Towards an African theology of public conversation

Zewde, Estifanos T. January 2017 (has links)
Public conversation is an important aspect of a day-to-day social life in African social world. Its scope also extends into the political realm, be being a critical dimension of democratisation in the continent. This dissertation aims at constructing the contours of an African theology of public conversation. It embarks on the analysis of the notion of ‘public' as understood within the constellations of African politics and African theology, with the aim of establishing the possibility of context-focused theological reflection on the role of public conversation in Africa. Taking a cue from the literature on the interactions between Jürgen Habermas and some theologians, it establishes the possibility of African theological reflection on communicative action and advance contextual sensitivity in theological constructions by bring cultural and local values that are of significance, without necessarily resorting into cultural nostalgia. To this end, the study turns to a detailed study of African palaver, a customary conflict-resolving mechanism, as a model of public conversation. Palaver stands as a paradigm of traditional consensual democracy, which is communally bound, narratively structured and enshrines anamnestic solidarity between the visible and invisible members of a community. It will be argued that the structured interplay between community, narrative and memory makes African palaver an effective tool of communicative action. In order to advance this argument, it will be demonstrated that palaver offers a site of argumentative reasoning, a kind of narrative rationality, conceived as alternative form of communicative rationality to the one suggested by Habermas. On a theological level, the study builds on Johannes Baptist Metz's memory-oriented narrative theology, as embodied by his idea of ‘dangerous memory' and advances the argument for a contextual theological categorisation of memory-oriented (anamnestic) solidarity. In the final analysis, the study provides a hypothetical ground for theological contextualisation on the basis of a symmetrical conversation between culture and theology.
62

Double Integrating Sphere Characterization of PVA-Cryogels

Fiee, Peter Q 26 January 2015 (has links)
Proper functioning of instruments requires precise calibration and routine quality assurance. In a clinical setting, this is achieved through the use of phantoms, which mimic the physical characteristics of tissues. Polyvinyl alcohol (PVA), a non-toxic, water-soluble polymer is well-suited for use as clinical phantom material. Through successive freezing and thawing, solutions of PVA in water can be solidified into rigid cryogels (PVA-C). The number of freeze-thaw cycles affects the properties of the material, including its optical characteristics. A double integrating sphere system was used in conjunction with the Inverse Adding Doubling (IAD) algorithm to characterize the optical properties of thin slab samples. The setup was evaluated using liquid phantoms. Liquid emulsion and food colouring were used to impart scattering and absorbing properties in the range characteristic of human tissue. Measured values of normalized reflectances and transmittances were entered into IAD, and a set of optical properties (μ′s,μa,g) retrieved. The reduced scattering coefficient was found to increase linearly with increasing lipid concentration, while a consistent overestimation of the absorption coefficient was observed. Measurements of PVA cryogels revealed a linear increase in the reduced scattering coefficient with an increasing number of freeze-thaw cycles up to five cycles. Scattering was also observed to increase with concentration up to PVA concentrations of 15%, and to spontaneously increase during the lifetime of the slab samples. These findings suggest it is possible to tune the optical scattering of PVA-C via different purely physical mechanisms. / Thesis / Master of Science (MSc)
63

Quantifying Chromophore Concentration in Tissue Simulating Phantoms Using an Optical Detection System Based on an Integrating Sphere

Moscu, Diana F. 12 1900 (has links)
<p> An integrating sphere system has been developed to study the optical properties of biological tissues non-invasively, over a broad spectral range with the ultimate goal of quantifying erythema resulting from external beam radiotherapy. An empirical model was defined to calculate the absorption coefficient, μa, from the normalized integrating sphere signal, R *, and the reduced scattering coefficient, μ's As erythema is associated with an increase in the apparent concentration of oxygenated haemoglobin in the skin, the potential of the technique in quantifying erythema was assessed using measurements made in homogenous tissue simulating phantoms containing whole horse blood. After system validation in this simple model, a two-layer model was investigated. Whole blood from a horse was added to the bottom layer, while the top layer was fixed at an optical thickness simulating the epidermis. Reflectance measurements were made through the top layer while the bottom layer was deoxygenated using yeast. The retrieved concentrations of oxy- and deoxygenated haemoglobin were used to calculate the total haemoglobin concentration and the haemoglobin oxygen saturation. Errors in estimating the total haemoglobin concentration ranged from 3-12%; decreasing as a broadband absorber was added to the top layer. Preliminary in vivo measurements were also performed on areas of erythema induced by a topical anesthetic. For regions of erythema there was an increase in the apparent haemoglobin oxygenation which correlates to values of the erythema index calculated from the definition established by Dawson et al. These results demonstrate that the apparent haemoglobin oxygenation has the potential to be used as a surrogate in quantifying erythema. </p> / Thesis / Doctor of Philosophy (PhD)
64

AN EXPERIMENTAL STUDY OF INCOMPRESSIBLE TURBULENT FLOW IN PIPES CONTAINING SPHERE TRAINS

Tawo, Edom 11 1900 (has links)
<p> The pressure gradients for sphere trains in 1 in. and 2 in. pipes have been measured with water flowing past the stationary spheres at Reynolds numbers (based on pipe diameter) from to 4 - 105 , and sphere/pipe diameter ratios ranging from 0.486 - 0.84. Two dimensionless pressure ratios have been derived so that the experimental results obtained can be generalised to any pipe diameter with the above constraints on Reynolds number and diameter ratio. Drag coefficients have also been calculated from pressure drop measurements for the 0.84 diam. ratio spheres in· 1 in. pipe. These have been compared with McNoun's drag coefficient. </p> <p> The application of the results to predict pressure gradients for sphere trains in any pipe diameter has been illustrated. </p> / Thesis / Master of Engineering (MEngr)
65

Java Simulator of Qubits and Quantum-Mechanical Gates Using the Bloch Sphere Representation

Shary, Stephen 20 April 2011 (has links)
No description available.
66

High Contrast Sphere-Supported Thin-Film Electroluminescent Devices

Shi, Yunxi January 2006 (has links)
<p> This thesis is concerned with the improvement of the contrast ratio of flexible display devices, which are Sphere Supported Thin Film Electroluminescent (SSTFEL) devices. A two-layer coating system was selected as anti-reflection (AR) coatings to be deposited on the surface of SSTFEL devices to reduce the reflection of the ambient light from the surface of devices based on the interference concept. This AR coating was composed of an ITO layer and an ultra-thin gold layer. In order to maximize destructive interference in the visible wavelength range, the optical properties, including refractive index, transmittance and reflection of ITO films and ultra-thin gold films related to sputtering conditions have been studied. The electrical conductance of these two films has also been explored because these two layers work not only as AR coatings but also as a conductive and transparent electrode of SSTFEL devices. AFM images show that the surface morphology of ultra-thin gold films on Si substrates is similar to that on an ITO layer and on polypropylene sheets. The measurements of specular and diffuse reflectance of AR coatings on the propylene sheets and devices have been performed in detail. Results show that AR coatings have better performance on the devices when the thickness of ultra-thin gold layers and ITO layers are 3.43 to 4.01nm, and 42.5 to 45.0nm respectively. Specular and diffuse reflectance of SSTFEL devices with AR coatings are around 1.3% and 13.6% respectively, which is 6.3 times less than that of devices without AR coatings. The contrast ratio of devices with AR coatings is up to 47.9:1 at the ambient illumination level of 52.6Lux. At the ambient illumination level of 200 Lux, the contrast ratio of SSTFEL devices is 5 times higher than that of SSTFEL devices without AR coatings. </p> <p> During the research on the properties of ultra-thin gold films, it has been observed that the ultra-thin gold film has unreported optical and electric properties when its thickness is around 3nm. Its reflectance spectrum is similar to the reflectance spectrum of the substrate, whether the substrate is a glass slide or a wafer of silicon, and follows the reflectance spectrum of the substrates with an increase of several percent in visible wavelength range. The conductance of the ultra-thin gold film decreases by exponential decay as its thickness decreases for the conductance is based on tunneling effects. However, the conductance suddenly increases while the thickness of the ultra-thin gold layer is decreased at around 3 to 4 nm. This behavior has not been reported and explained. </p> / Thesis / Master of Applied Science (MASc)
67

Deliberation, Dissent, and Advocacy: A Rhetorical Study of Teachers' Lived Experiences with Education Reform

Garahan, Katie Lynn 23 April 2019 (has links)
Contemporary K-12 education reform policies have focused heavily on the teaching profession through increased accountability measures and decreased job security. In the rhetoric of contemporary reform, teachers are often praised as heroes capable of overcoming any obstacles and at the same time blamed for the perceived failures of public schools. This dissertation examines the impact of such policies and corresponding representations on the lived experiences of K-12 teachers in North Carolina, specifically highlighting the strategies through which teachers gain rhetorical agency within the discursive space of reform. To do so, I apply an analytical frame of public sphere theory and employ a mixed-methods approach that combines archival methods and fieldwork (e.g. participant observation and interviews). This dissertation argues that teachers' discourses provide alternative narratives to the dominant view that modifying the teaching profession is a cure-all for educational problems. I first develop a history of contemporary education reform in North Carolina and argue that within these discourses, teachers are represented as heroes able to do more work with less pay under increased scrutiny. Then, analyzing images of protest signs collected at the May 16 teacher rally in Raleigh, North Carolina, I argue that teachers rhetorically perform their professional identities as student advocates, champions of public educators, and political dissenters. As such, they dismantle dominant representations of their profession and advance a notion of public education that values collaboration, equitability, and the public good. Last, I examine how teachers negotiate the tension between their goals and the constraints of policy, arguing that contemporary reform undermines teachers' expertise. At the same time, teachers devise strategies to work toward their visions of public education. Such strategies include building relationships, being persistent, de-prioritizing policy, and cultivating community. / Doctor of Philosophy / Contemporary K-12 education reform policies have focused heavily on the teaching profession through increased accountability measures and decreased job security. In the rhetoric of contemporary reform, teachers are often praised as heroes capable of overcoming any obstacles and at the same time blamed for the perceived failures of public schools. This dissertation examines the impact of such policies and corresponding representations on the lived experiences of K-12 teachers in North Carolina. To do so, I employ an approach that combines archival methods and fieldwork (e.g. participant observation and interviews), and rhetorical analysis. This dissertation argues that teachers’ discourses provide alternative narratives to the dominant view that modifying the teaching profession is a cure-all for educational problems. I first develop a history of contemporary education reform in North Carolina and argue that within these discourses, teachers are represented as heroes able to do more work with less pay under increased scrutiny. Then, analyzing images of protest signs collected at the May 16 teacher rally in Raleigh, North Carolina, I argue that teachers rhetorically perform their professional identities as student advocates, champions of public educators, and political dissenters. As such, they dismantle dominant representations of their profession and advance a notion of public education that values collaboration, equitability, and the public good. Last, I examine how teachers negotiate the tension between their goals and the constraints of policy, arguing that contemporary reform undermines teachers’ expertise. At the same time, teachers devise strategies to work toward their visions of public education. Such strategies include building relationships, being persistent, de-prioritizing policy, and cultivating community.
68

以公私領域概念充實Dewey教育理論之研究 / A Study on The Dewey’s Educational Theory through The Concepts of Public and Private Spheres

葉彥宏, Ye, Yan Hong Unknown Date (has links)
人類的政治與日常生活內容存在於公共領域和私領域中,隨著社會的自由化與民主化,公私領域也對教育產生影響。本研究把公共領域視為政治生活的空間,人們在其中通過彼此的共同經驗來討論各種議題。私領域則是涉及自身關係與親密關係等內容,其發展與公共領域有密不可分的關係。本研究重新描述了Dewey教育理論中的經驗與民主等概念,且針對其中的不足之處,企圖以公私領域的概念加以充實之。研究者主要從四個部分的分析來重構Dewey的理論:一、增加生活經驗的多樣性;二、社會化與個性化的兼顧;三、公共與私人的民主生活;四、民主教育的自主與團結。根據上面的分析,最後研究者對Dewey的教育理論提出了四點建議:第一,把公私領域的概念融入Dewey的經驗理論中,使人們注意到在經驗的連續性及交互作用中,存在那些公共與私人生活的複雜關係;第二,重申個性化和社會化必須兼顧的重要性;第三,瞭解各種團體的互動關係能使共同生活更為完善;第四,把各種公共與私人的關係納入考量中,將有助於彰顯出完整的人類生活面貌。 / The politics and daily life of human lay both in the public and the private sphere, along with the liberalization and democratization in the society, the public and the private sphere also bring about influence on education. The study treats public sphere as the realm of political life. In the realm, people discuss various subjects with their associated experiences. The private sphere involves self and intimacy relations, their development have inseparable relevance to public sphere. The study redescribes the concepts of experience and democracy in the Dewey’s educational theory, and attempts to enrich his shortage with the concept of the public and the private sphere. The Author reconstructs Dewey’s educational theory by four points: Adding the variation of life experiences, giving equal attention to socialization and individualization, public and private democratic life, autonomy and solidarity of the democratic education. Accordingly, the author proposes four suggests to Dewey's educational theory: Firstly, if people want to understand the complexity of the public and the private life, they need to integrate the public sphere and the private sphere into Dewey’s experience theory. Secondly, reiterating the importance of the individualization and the socialization must be given equal attention. Thirdly, understanding the interactive relationships in various associations could cause to a better associated living. Fourthly, it will be helpful to show a complete human life by taking all kinds of the public and the private relation into account.
69

Varför bestiga berg?

Tingström, Emilia, Axelsson, Linus January 2013 (has links)
This essay will focus on the people using and are involved in, and have a large interest in the horror film genre. The purpose of this essay is to find what urge these people to continuously watch horror movies and how they believe to be acknowledge by the society in a modern sense. Our study is mainly based on two separate interviews and therefore, mainly from the users perspective. This essay is also complemented by earlier research on this topic. In context of stigma, violence debate, exclusion we found that the users truly can be found in a rare type of alternative sphere, besides the public sphere. But this is also in relationship with age and gender of the user. Our stands in all this is that horror movies should be accepted as an escape from reality, not a genre that twist people to become violent, and that users can see the difference between reality and fiction and using horror movies should not be considered a deviant behavior in a modern society.
70

Digitala julhälsningar : De virala kommunikatörerna, offentligheten och demokratin

Torgnysdotter, Anna-Sara January 2010 (has links)
Title: Digital christmas greetings - the viral communicators, public sphere and democracy(Digitala julhälsningar - de virala kommuniktörerna, offentligheten och demokratin)Number of pages: 41Author : Anna-Sara TorgnysdotterTutor: Ylva EkströmCourse : Media and Communication Studies DPeriod: Spring, semester 2010University: Devision of Media and Communications, Department of Information Science,Uppsala UniversityPurpose: The purpose of this study is to see if social media could be an arena for the usersto increase democracy and the public sphere. Studying the role and possibilitys of the individual.Is there a space for any one to act and debate?Method: A qualitative analysis based on interviews with ten users of social media - viralcommunicators. They were discussing public and private sphere, democracy, norms andbehavior in social media.Theoretical platform: The theoretical basis has its roots in sociology: Ervin Goffman´sidea on self-presentation and social interaction, Manuel Castels´ theories of the networksociety and Jürgen Habermas idea of the public spehere.Main result: The viral communicators are ambivalent in their use of socialmedia. They are users because they want to be but also because they feel forced to - professionalor private. Their primary aim in communicating in social media could summarize“self-expression”.The users of social media talks contradictivly about their feelings wheter they feel safe orunsafe in the social media situation.They talk about lacking time to debate on the internet and they feel confused about what´sprivate and whats public.Social norms and unwritten laws rules communication in social media and the loosening inpublic and private sphere creates confusion about to whom and where you communicate.This results in avoiding messages that might offend or harass. Because the viral communicatorscommunicate with a broad group of people, including every one - from your cousin toyour boss - there is a vague idea of the tolerance from the target audiences and therefor themessages tend to be very conservative and safe.The viral communicator uses that public arena the social media offers like traditional postcards. A christmas greeting to keep in touch and stress their prosperity and wellbeing.Keywords : Social media, viral communication, Habermas, Goffman, Castells, publicsphere, private sphere, social norms, unwritten laws

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