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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.
41

VECTOR QUANTIZATION USING ODE BASED NEURAL NETWORK WITH VARYING VIGILANCE PARAMETER

Khudhair, Ali Dheyaa 01 May 2012 (has links)
Vector Quantization importance has been increasing and it is becoming a vital element in the process of classification and clustering of different types of information to help in the development of machines learning and decisions making, however the different techniques that implements Vector Quantization have always come short in some aspects. A lot of researchers have turned their heads towards the idea of creating a Vector Quantization mechanism that is fast and can be used to classify data that is rapidly being generated from some source, most of the mechanisms depend on a specific style of neural networks, this research is one of those attempts. One of the dilemmas that this technology faces is the compromise that has to be made between the accuracy of the results and the speed of the classification or quantization process, also the complexity of the suggested algorithms makes it very hard to implement and realize any of them on a hardware that can be used as a fast-online classifier which can keep up with the speed of the information being presented to the system, an example for such information sources would be high speed processors, and computer networks intrusion detection systems. This research focuses on creating a Vector Quantizer using neural networks, the neural network that is used in this study is a novel one and has a unique feature that comes from the fact that it is based solely on a set of ordinary differential equations. The input data will be injected in those equations and the classification would be based on finding the equilibrium points of the system with the presence of those input patterns. The elimination of conditional statements in this neural network would mean that the implementation and the execution of the classification process of this technique would have one single path that can accommodate any value. A single execution path will provide easier algorithm analysis and open the possibility to realizing it on a pure analog circuit that can have an operation speed able to match the speed of incoming information and classify the data in a real time fashion. The details of this dynamical system will be provided in this research, also the shortcomings that we have faced and how we overcame them will be explained in particulars. Also, a drastic change in the way of looking at the speed vs. accuracy compromise has been made and presented in this research, aiming towards creating a technique that can produce accurate results with high speeds.
42

Shock Metamorphism in Ordinary Chondrites: Constraining Pressure and Temperature History

January 2016 (has links)
abstract: Shock metamorphism in meteorites constrains the impact histories of asteroids and planets. Shock-induced high-pressure (HP) minerals can provide more precise estimates of shock conditions than shock-induced deformation effects. In this research, I use shock features, particularly HP minerals, in ordinary-chondrite samples to constrain not only shock pressures but also the pressure-temperature-time (P-T-t) paths they experienced. Highly shocked L5/6 chondrites Acfer 040, Mbale, NWA 091 and Chico and LL6 chondrite NWA 757 were used to investigate a variety of shock pressures and post-shock annealing histories. NWA 757 is the only highly shocked LL chondrite that includes abundant HP minerals. The assemblage of ringwoodite and majoritic garnet indicates an equilibration shock pressure of ~20 GPa, similar to many strongly shocked L chondrites. Acfer 040 is one of the only two chondrite samples with bridgmanite (silicate perovskite), suggesting equilibration pressure >25 GPa. The bridgmanite, which is unstable at low-pressure, was mostly vitrified during post-shock cooling. Mbale demonstrates an example of elevated post-shock temperature resulting in back-transformation of ringwoodite to olivine. In contrast, majoritic garnet in Mbale survives as unambiguous evidence of strong shock. In these two samples, HP minerals are exclusively associated with shock melt, indicating that elevated shock temperatures are required for rapid mineral transformations during the transient shock pulse. However, elevated post-shock temperatures can destroy HP minerals: in temperature sequence from bridgmanite to ringwoodite then garnet. NWA 091 and Chico are impact melt breccias with pervasive melting, blackening of silicates, recrystallization of host rock but no HP minerals. These features indicate near whole-rock-melting conditions. However, the elevated post-shock temperatures of these samples has annealed out HP signatures. The observed shock features result from a complex P-T-t path and may not directly reflect the peak shock pressure. Although HP minerals provide robust evidence of high pressure, their occurrence also requires high shock temperatures and rapid cooling during the shock pulse. The most highly shocked samples lack HP signatures but have abundant high-temperature features formed after pressure release. / Dissertation/Thesis / Doctoral Dissertation Geological Sciences 2016
43

The effect of different Ordinary Portland cement binders, partially replaced by fly ash and slag, on the properties of self-compacting concrete

Almuwbber, Omar Mohamed January 2015 (has links)
Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Civil Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology / Self-compacting concrete (SCC) is a flowable self-consolidating concrete which can fill formwork without any external vibration. A self-compacting concrete mix requires the addition of superplasticiser (SP), which allows it to become more workable without the addition of excessive water to the mixture. The effect of different CEM I 52.5N cements produced by one company at different factories on self-compacting concrete was investigated. The properties of SCC are highly sensitive to changes in material properties, water content and addition of admixtures. For self-compacting concrete to be more accepted in South Africa, the effect that locally sourced materials have on SCC, partially replaced with extenders, needs to be investigated. The European guidelines for SCC (2005) determined the standard, through an extensive study, for the design and testing of self-compacting concrete. Using these guidelines, the properties of self-compacting concrete with the usage of local materials were investigated. The effect on SCC mixes was studied by using four cements; two types of SPs – partially replaced with two types of fly ash; and one type of slag. Mix design and tests were done according to the European Specification and Guidelines for Self-Compacting Concrete (2005). Using locally sourced materials (different cements, sand, coarse aggregate, fly ashes and slag), mixes were optimised with different SPs. Optimisation was achieved when self-compacting criteria, as found in the European guidelines, were adhered to, and the binders in these required mixes were then partially replaced with fly ash and slag at different concentrations. Tests done were the slump flow, V-funnel, L-box, sieve segregation resistance as well as the compressive strength tests. The results obtained were then compared with the properties prescribed by the European guidelines. The cements reacted differently when adding the SPs, and partially replacing fly ash and slag. According to the tests, replacing cement with extenders – in order to get a sufficient SCC – seemed to depend on the chemical and physical properties of each cement type, including the soluble alkali in the mixture, C3A, C3S and the surface area. The range, in which the concentration of these chemical and physical cement compounds should vary – in order to produce an acceptable SCC partially replaced by extenders – was determined and suggested to the cement producer. The main conclusion of this project is that cement properties vary sufficiently from factory to factory so as to influence the performance of an SCC mix. The problem becomes even bigger when such cements are extended with fly ash or slag, and when different SPs are used. When designing a stable SCC mix, these factors should be taken into account.
44

Discursos diagnósticos pós-lacanianos: dos fundamentos em psiquiatria às teses sobre um novo sujeito / Discourses of post-lacanian diagnosis: from psychiatric foundations to theses about a new subject

Daniele Rosa Sanches 16 July 2015 (has links)
A pesquisa tem por objetivo geral construir um mapeamento dos principais discursos diagnósticos pós-lacanianos que se circulam no Brasil. Um primeiro objetivo específico desta tese é distinguir a racionalidade subjacente comum a diferentes autores. O segundo objetivo específico é realizar uma breve indicação dos elementos conceituais que se destacam em cada discurso, um destaque que nos revelas as chaves para abrir o debate a ser realizado mais adequadamente nas considerações finais. A justificativa desta pesquisa reside na possibilidade de oferecer ao campo da psicanálise uma inédita visão de conjunto do universo diagnóstico pós-lacaniano. Neste intuito, nossa tese possui uma primeira parte que tem função histórica de situar o campo em debate e refazer os primeiros passos de construção do pensamento diagnóstico em Lacan, assim oferecemos as condições prévias para acompanhar a subsequente discussão pós-lacaniana. Optamos por realizar esta apresentação histórica, pois a hipótese com a qual trabalhamos é que alguns fundamentos do período nascente da obra lacaniana, da década de trinta e quarenta, retornam como questão no debate pós-lacaniano. Na sequencia, temos dois grupos discursivos que trabalham diretamente ligados ao texto de Lacan. O primeiro grupo de autores representa a visão da diagnóstica clássica, pois faz uma redescrição das três estruturas clínicas (neurose, psicose e perversão) e adota esta racionalidade como modelo diagnóstico padrão da obra lacaniana; já o segundo grupo de autores defende a necessidade de reformulações na diagnóstica lacaniana, pois postula a insuficiência do modelo das estruturas clínicas; tais autores estão unidos pela hipótese de que a obra de Lacan possui rupturas conceituais determinantes para uma reacomodação diagnóstica. Por fim, os dois últimos capítulos de nossa tese define um terceiro grupo discursivo que não extrai sua interpretação diretamente do texto de Lacan, mas sim de um diagnóstico social sobre o declínio da função paterna na atualidade, donde cada autor fará sua hipótese para um novo sujeito contemporâneo. Enquanto resultado adicional desta pesquisa, verificamos que as problemáticas clínicas da esfera do Eu retornam ao campo lacaniano de modo direto ou indireto. Como conclusão constatamos que o tema do declínio da função paterna, o desentendimento acerca do alargamento conceitual da categoria de psicose (através da psicose ordinária e psicose compensada) e, por fim, o uso variável da noção de suplência, são os principais elementos dos discursos pós-lacanianos que nos dão as chaves para o debate diagnóstico na atualidade / This research aims to map the main discourses of post-lacanian diagnosis that spread in Brazil. This thesis first specific objective is to differentiate the underlying rationality common to different authors. The second specific objective is to make a brief indication of the conceptual elements that stand out in each discourse. This reveals the keys to open the debate to be more adequately done in our closing remarks. The justification of this research resides in the possibility of offering to the psychoanalytic field an original overview of the post-lacanian diagnostic universe. In order to do so, we first locate historically the field at issue and remake the first steps of Lacans diagnostic thought. This subsidies the ensuing post-lacanian debate. Our hypothesis is that some fundamentals of the first part of the lacanian oeuvre, comprising the 1930s and the 1940s, return in the form of a question in the post-lacanian debate. We present then two discursive groups that are directly related to the lacanian text. The first group of authors represents the classic diagnostic view, since they do a redescription of the three clinic structures (neurosis, psychosis and perversion) and adopt this rationale as the standard diagnostic model in the lacanian oeuvre. The second group of authors defends the necessity of reformulations in lacanian diagnostic, postulating the insufficiency of the clinic structures model. These authors gather around the hypothesis that the lacanian oeuvre has conceptual ruptures that are decisive for diagnostic reaccommodation. The two last chapters define a third discursive group that does not extract its interpretation directly from lacanian text, but from a social diagnosis about the decline of the paternal function nowadays. Each author will hypothesize about a new contemporary subject. As an additional result, we found that the clinical problematic of the Ego returns to the lacanian field both direct and indirectly. We conclude that the main elements of the post-lacanian discourses that grant us the keys to the nowadays diagnostic debate are 1) the decline of the paternal function; 2) the misunderstanding regarding the broadening of the category of psychosis (ordinary psychosis and compensation psychosis) and 3) the variable use of the notion of supplant
45

The new East Window of St Martin-in-the-Fields Church, London : a window of opportunity for developing ordinary theology through a visual image

Betts, Edmund John January 2014 (has links)
Ordinary theology is a developing concept focusing on people’s explicit religious beliefs, and relying on anecdotal evidence and other academic writers to bridge the gap with academy theology. It has influenced empirical studies of ordinary people’s experience with the Bible, doctrine and cathedral visiting. A feminist qualitative ethnographic study and action research provide other voices as alternatives to this empiricism. Theologians-in-the-arts have appropriated art to illustrate their academic theology. This thesis takes further the use of a visual image, with a recently commissioned non-figurative designed window, by a female Iranian-born artist, in an well-known London church. It enquires how far a non-specific doctrinal and non-narrative window encourages wider public participation in meaning making and metaphor generation, challenging the current static concept of ordinary theology. An interpretative paradigm with perspectives from constructivism, phenomenology, and hermeneutics shapes an inductive and qualitative approach to give attention to regular worshippers and visitors. A visual ethnographic method elicits data through semi-structured questionnaires, interviews, and journal writing. Adopting a ‘lay’ outsider participant role during the fieldwork, unstructured situational interviews with passers-by, street traders and church staff were also undertaken. Interpretive lenses of framing, the pastoral cycle, ethnomethodology, and nitty-gritty hermeneutics assisted in analysing the data. The window attracted a high degree of participation, engaging people in reflection. Over 85% of participants were professional/university and technically educated and competent in academic disciplines other than theology. The respondents initially made non-religious statements challenging ordinary theology, which focussed on explicit religion. When respondents viewed it a second time, they used religious concepts. The analysis led to the construction of ordinary portraits constructed of previously not heard voices and challenged the earlier faces of academic partners. The window is a dialogically framed ‘lived experience’ breaking the ‘is’ of metaphor and the gestalt law of closure. This research explores the ‘is not’ of metaphor. It explores the relationship of image, metaphor and concept by focussing on window parts; the images of centre, line and web. The window becomes both a working metaphor and a model of working metaphors extensively used by these participants. Ordinary theology discovers through feminist metaphorical theology that concepts are metaphorical, focusing on both dissimilarities and similarities. The window as a visual image provides an opportunity to extend the concept and metaphor of ordinary theology. It invites academic professionals to an intensive fieldwork experience using a visual image to rediscover a general process of reflection and to reveal people’s indirect and implicit metaphorical ordinary theology.
46

La ruralité au comptoir : une géographie sociale et culturelle des cafés ruraux bretons / The rural life at the counter : a social and cultural geography of Breton rural coffees

Cahagne, Nicolas 11 December 2015 (has links)
En France comme dans l’ensemble des pays industrialisés, la ruralité, entendue comme construction sociale du monde, se transforme. La mobilité croissante des individus, l’installation de nouvelles populations, l’urbanisation des esprits, setraduisent par de nouvelles manières d’habiter la campagne. Cette thèse apporte sa contribution à l’analyse de la ruralité contemporaine à travers l’étude des pratiques des cafés en interrogeant le déclin et les formes de résistance des cafés dans les espaces ruraux bretons.D’un point de vue général, notre questionnement est double : il porte d’une part sur l’évolution des campagnes et la construction des ruralités contemporaines et, d’autre part, sur les modes d’habiter des ruraux, plus exactement sur la pratique des cafés au sein de ces modes d’habiter. L’un, regard surplombant, et l’autre, regard de terrain, se soutenant mutuellement. Dans un premier temps, nous interrogeons les profils et les stratégies des cafetiers face à la crise des cafés. Cette analyse débouche sur une typologie des cafés ruraux fondée sur les activités et services proposés et met en évidence l’émergence de cafés alternatifs. Dans un second temps, ce sont les pratiques spatiales ordinaires des clients qui sontmises à l’épreuve de cette diversité des cafés ruraux. Les choix des cafés effectués par les clients apparaissent comme dictés par une volonté de différenciation sociale dans l’espace local. / In France, as in all industrialized countries, rurality, defined as social construction of the world, evolves. Mobilities of people, newcomers in rural spaces and urbanization of minds result in new ways of living in countryside. This thesis wants to analyse today rurality by studying drinking establishments practices. It questions decline and forms of renewal in drinking establishments in rural spaces of Brittany. The methods combine interviews with owners and patrons, ethnographic materials and a survey. So we can study profiles and strategies of drinking establishment owners. We propose a typology of drinking establishments in rural Brittany based on activities and products and we highlight the emergence of “alternative” bars. Then, we study the diversity of drinking establishment practices. Patrons’ choices of their bars appear to be related tosocial differentiations in the rural space.
47

Liveable places : housing biographies in a Manchester neighbourhood

Cole, Dawn Nicola January 2016 (has links)
This thesis explores how individuals and households experience the places in which they live and examines the potential impact of those places on outcomes across a range of life careers. Residential neighbourhoods have been variously framed as sites of personal expression or alternatively as locations of multiple deprivation that limit the life chances of the local population. This thesis however, argues that the limited framework within which existing studies of housing and residential choice are developed provides only a partial account of the complex and multidimensional nature of the relationship people have with the places in which they live. It addresses this gap by drawing on a wide range of theoretical ideas and by moving away from the deficit model of housing that dominates much academic work. In doing so it opens up the subject to scrutiny from a variety of perspectives and lays bare the varied and competing influences on decisions about housing. Use of quantitative information in the form of detailed housing biographies addresses a gap in existing knowledge by placing housing decisions in the context of past experience and other life careers. The introduction of qualitative techniques to a discipline dominated to date by large scale surveys supplements this evidence with the rich, nuanced data of personal experience. Three key elements of housing practices are identified, demonstrating the extent to which they are inextricably interconnected with a range of other life careers. Despite the recent ascendency within geography of a relational sense of place at the expense of the territorial, both are seen to be important. Savage et al’s (2005) concept of elective belonging is clearly identified as residents construct a narrative of fit between self and neighbourhood. Multiple strategies of social distinction are observed, each of which serves to transform the house and the neighbourhood into a home. Secondly notions of community remain an essential element of residents’ sense of belonging to their neighbourhood. The research reveals highly focussed personal networks that serve to produce and sustain location specific capital. An un-reflexive immobility is the result, where settled households perceive little need to consider residential alternatives. Finally, the physical and social infrastructure provided by the neighbourhood is identified as an important means of mediating the demands of home, work and childrearing. As such women, as primary care-givers, show greater investment than male partners in the ‘right’ residential choice. The thesis reveals liveable place to be complex and multifaceted, difficult to reduce to a simple economic or social variable. Whilst there are constant characteristics which appeal across the social scale, it highlights divergent experiences according to class, gender and life course stage. Choices and outcomes are embedded in social structures so that the research demonstrates the on-going impact of liveable place in the accumulation of social, cultural and economic capital to those who live there. Whilst liveable place is seen to mean different things according to class, gender and age, those trapped in neighbourhoods they do not consider liveable are potentially excluded from this accumulation.
48

Capital structure and determinants of capital structure, before, during and after the 2008 financial crisis: A South African study

Ntshobane, Gcobisa 15 September 2021 (has links)
This study examines the effects of 2007/8 financial crisis on capital structure determinants of Johannesburg Stock Exchange (JSE) listed companies in South Africa. Data extracted from INET BFA Expert database was analyzed using regression models on the correlation between the leverage and company size, growth, profitability, tangibility, liquidity, non-debt tax shield along with Ordinary Least Squares based on the sample of JSE listed companies for the period of 2004 to 2013. The study examined two industries namely, Real estate and Retail industry. The results show that size, tangibility, profitability and liquidity have significant impact on the capital structure before, during and after financial crisis. Growth results were inconsistent over the period under review, and non-debt tax shield was found to be statistically insignificant. The study also shows that the 2007/8 had statistical significance on the capital structure of the listed companies in South Africa.
49

Two Types of Typicality: Rethinking the Role of Statistical Typicality in Ordinary Causal Attributions

Sytsma, Justin, Livengood, Jonathan, Rose, David 01 December 2012 (has links)
Recent work on the role of norms in the use of causal language by ordinary people has led to a consensus among several researchers: The consensus position is that causal attributions are sensitive to both statistical norms and prescriptive norms. But what is a statistical norm? We argue that there are at least two types that should be distinguished-agent-level statistical norms and population-level statistical norms. We then suggest an alternative account of ordinary causal attributions about agents (the responsibility view), noting that this view motivates divergent predictions about the effect of information about each of the two types of statistical norms noted. Further, these predictions run counter to those made by the consensus position. With this set-up in place, we present the results of a series of new experimental studies testing our predictions. The results are in line with the responsibility view, while indicating that the consensus position is seriously mistaken.
50

In-situ quantitative analysis of trace elements in metal grains from H,L and LL ordinary chondrites using femtosecond laser ablation-ICP-mass spectrometry / フェムト秒レーザーアブレーションICP質量分析法によるH, L, LL普通コンドライト中金属粒子の局所微量元素分析

Yokoyama, Takaomi 23 July 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18495号 / 理博第4010号 / 新制||理||1578(附属図書館) / 31381 / 京都大学大学院理学研究科地球惑星科学専攻 / (主査)教授 平田 岳史, 准教授 伊藤 正一, 教授 土`山 明 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

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