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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.
71

Les industries de la musique au prisme des acteurs de l’intermédiation numérique : une analyse des logiques socio-économiques et des pratiques communicationnelles des musiciens / The music industries through the prism of intermediating digital players : an analysis of the musician's socio economic logics and communication practices

Costantini, Stéphane 08 July 2014 (has links)
Depuis les années 2000, l’émergence de nouveaux acteurs issus des industries de lacommunication a été suivie de profonds bouleversements au sein des industries de la musique. L’hypothèse développée dans cette recherche suggère que, par l’intermédiaire d’un mouvement d’influence réciproque des musiciens et des acteurs de la musique, s’opère un déplacement vers la création du centre de gravité de l'industrialisation de la musique. L’adaptation des logiques socioéconomiques des musiciens, en phase avec les stratégies industrielles des acteurs de l’intermédiation numérique, indique la montée en importance des dimensions de rationalisation et d’idéologisation au sein des mondes de la musique. La démarche méthodologique adoptée s’appuie sur une analyse des discours et des pratiques socio-économiques des musiciens, au moyen d’une série d’entretiens semi-directifs réalisés en France et au Royaume-Uni. Les résultats de ces analyses mettent notamment en lumière chez les « musiciens connectés » étudiés, la disparité des pratiques, des compétences et des représentations à l’égard des activités de diffusion et de communication sur internet. Les disparités de ces pratiques font alors ressortir les enjeux relatifs à la construction de la figure contemporaine du musicien. Mots-clés : théories des industries culturelles, industries de la musique, industries de la communication, internet, Web 2.0, genres musicaux, pratiques communicationnelles, compétences, représentations sociales, rock, musiques électroniques, France, Royaume-Uni. / Since the 2000s and the emergence of new players from the communication industries, profound changes have occurred within the music industry. The hypothesis developed in this research suggests that, following a movement of mutual influence between musicians and economic players, there has been a shift in emphasis towards the industrialization of music, which is now concerning the creation itself. The adaptation of the musicians’ socio-economic logics, in line with the industrial strategies of the actors of the digital world, indicates the growing importance of rationalization and ideologization in the music worlds. The methodological approach is based on the analysis of discourses and socio-economic practices of musicians, using semi-structured interviews made in France and the United Kingdom. The results of these analyses highlights the the great disparity of the practices, skills and representations of these ‘connected musicians’, with regard to dissemination and communication activities on the internet. These practices’ disparities outlines the issues relating to the construction of the musician’s contemporary figure.
72

A qualitative approach to financial risk

Shedden, Jason Patrick 09 May 2007 (has links)
Research indicates that the dynamics and complexities driving and challenging business organisations in the current era have increased exponentially in the recent past. As a result more complex demands are being placed on organisations to adapt to an ever-changing environment. This adaptation to change is demanding more flexible structures capable of enduring the dynamics of current market risks. This research proposed that such endurance is possible by reconsidering the current paradigm that governs an understanding of risk. It is proposed that risk to date has been focused on a quantitative perception. In the light of this a comprehension from a qualitative perspective is proposed. This comprehension will then permit concepts from a number of diverse disciplines to be incorporated into an alternative paradigm on risk. As such a more creative approach to understanding risk can be presented. This dissertation will focus on introducing creativity into the current understanding of risk in a bid to produce a qualitative risk model capable of not only defining an alternative definition of risk but also providing solutions to managing risk. In this manner, it is proposed that a trend toward a more flexible organisational structure will arise and a comprehension of risk that is more in keeping with current economic trends will result. / Dissertation (Magister Commercii (Financial Management Sciences))--University of Pretoria, 2007. / Accounting / unrestricted
73

The background, architectural philosopy and work of Hellmut Wilhelm Ernst Stauch

Nation, Shelagh Suzanne 09 December 2008 (has links)
The thesis deals with Stauch’s childhood background, his youth and early involvement with sailing, art and architecture in Germany. The initial belief that he received his architectural training at the Bauhaus was investigated and found to be incorrect. The details of his training at the Ittenschule, his employment by first Forbat and then Peters, and his private practice in Berlin are described. The circumstances of his move from Berlin to South Africa and his employment by Nunn are discussed. The establishment of his own office in Pretoria, his registration with the Institute of South African Architects and a short-lived partnership with Wepener followed by the establishment of his present practice now known as Stauch Vorster, is described. Stauch’s architectural approach and philosophy are discussed in broad terms. Illustrations of his work are included chronologically within the text. / Dissertation (MArch)--University of Pretoria, 2008. / Architecture / unrestricted
74

Solutions of the Equations of Radiative Transfer by an Invariant Imbedding Approach

Adams, Charles N. 01 1900 (has links)
This thesis is a study of the solutions of the equations of radiative transfer by an invariant imbedding approach.
75

A pluralistic, socio-ecological approach to understand the long-term impact of mountain conservation: a counterfactual and place-based assessment of social, ecological and hydrological change in the Groot Winterhoek Mountains of the Cape Floristic Region

Holden, Petra Brigitte 24 August 2018 (has links)
The problem: For protected areas to remain relevant, we need to understand their impact on a wide set of conservation objectives and environmental outcomes. We also need to evaluate how this influence relates to the socio-ecological environment within which they occur. This is a complex endeavour requiring a pluralistic approach, which draws on a wide range of interdisciplinary fields. Research question: This thesis addresses the following question: What effects do mountain protected areas have on ecosystem services over time and how does this influence relate to broader socio-economic and ecological drivers of landscape change? Aim and objectives: I use a pluralistic, socio-ecological framing to assess the impact of ~40 years of mountain protection, drawing on comparisons of ~30 and ~40 years before and after protection respectively, with an adjacent area of similar terrain informing scenarios of counterfactual conditions. I also investigate what types of values (economic and intrinsic) are important when determining the impact of mountain protected areas. Thesis approach and methods: I operationalise the concepts of socio-ecological systems, ecosystem services, land use transitions and counterfactuals to investigate socio-ecological change and how it relates to protected area impact in the Groot Winterhoek, a mountain catchment in the south-western Cape of South Africa. This mountain catchment is important for regional water supplies for agricultural and domestic uses and falls in the Cape Floristic Region, a global biodiversity hotspot. It is comprised of privately owned mountain wildlands and a wilderness-protected area, known as the Groot Winterhoek Wilderness Area, established in 1978 (gazetted in 1985) which forms part of the Cape Floristic Region World Heritage Site. I combine methods from social science, ecology, environmental geography, geomatics and hydrology to understand the history of land use and cover (land use/cover) and associated ecosystem service trade-offs, how they are perceived by landowners as well as their wider impact on the region. Specifically, I assess the impact of protection on land use/cover, vegetation, fire and water flows over the last ~50 years, by comparing and contextualising results of change within the protected area to alternative scenarios of “no protection” (the counterfactual conditions). Vegetation and land use/cover change inside the protected area were determined respectively using 72 repeat terrestrial photographs and vegetation surveys, and an analysis of orthorectified aerial imagery. Methods used to construct the counterfactual scenarios of mechanisms (e.g. changes in land use/cover) that would likely drive vegetation changes inside the protected area included: i) 60 repeat surveys and in-depth interviews with landowners adjacent or proximal to the protected area owning unprotected land of similar terrain to the protected area; and ii) land use/cover change analysis of orthorectified aerial imagery of adjacent unprotected land of similar terrain before and after protected area establishment. 4 This latter information was used to understand the role of the protected area in driving vegetation changes inside the protected area. Social, biophysical and remote sensing results were directly used to parameterise land use/cover components of a hydrological model to determine the influence of protection on water flows. Specifically, water flows were simulated for the current state of the environment inside the protected area as well as for several counterfactual scenarios i.e. the alternative land use/cover scenarios of “no protection”. These counterfactual scenarios included land use/cover at two-time steps of ~30 and ~8 years before protection and one-time step ~40 years after protection both inside and outside the protected area. Results: Long-term change in ecosystem service use outside the protected area on privately owned land of similar terrain to inside the protected area (Section 3): Over the last ~50 years, outside the protected area, there was a shift from livestock-based, subsistence agriculture and small-scale farming to a diversified set of ecosystem service uses. The combined area of grazing and wildflower harvesting declined by 39%, while the number of landowners using the mountains for personal nature-based recreation and ecotourism increased by 61% and 23% respectively. Agriculture intensified in suitable areas of mountain land with the number of landowners cultivating land increasing by 20%. Exogenous socioeconomic drivers associated with globalisation and economic growth were important causal mechanisms of land use change. Landowners valued mountain protection for intrinsic and non-use reasons (73-80% of landowners), including existence, bequest and option values, as well as for the indirect use of water supply (72% of landowners) in comparison with direct use reasons such as spiritual/cultural experiences and nature-based recreation inside the protected area (18 and 50% of landowners respectively). Personal, nature-based recreation outside the wilderness-protected area was associated with valuing the protection of mountain land for intrinsic and non-use reasons. Long-term vegetation change inside the protected area and plausible mechanisms driving vegetation change (Section 4): Inside the mountain protected area, fynbos vegetation cover increased on average between 11 and 30% and there were significant declines in bare ground and rock cover. In 5 accumulation and fire intensities. However, these latter changes in land use/cover also occurred outside the protected area (see results summarised for Section 3 above and Section 4 below) and therefore cannot be attributed to protected area establishment. Land use/cover and the influence on water flows inside the protected area compared to counterfactual scenarios of no protection (Section 5): Declines in grazing and changes to the fire regimes occurred regardless of the protected area boundaries. In the past, there was a high frequency of small, low intensity fires across the landscape, both inside and outside the protected area. More recently, fires have been actively suppressed and this resultsin the build-up of biomass and the development of extensive, high intensity fires which, under suitable conditions, burn large expanses of the mountain catchment. Hydrological modelling showed that a high intensity burning regime negatively affected streamflow regardless of protected area boundaries. Streamflow increased by more than 80% under high flow conditions and decreased by more than 40% under low flow conditions relative to an unburnt ‘natural’ scenario. Over the last 50 years there has also been a substantial increase in dams, buildings and roads and minor increases in cultivation outside the protected area. This has been avoided inside the protected area where these land use/cover classes declined. If the increase in these land use/cover types observed outside the protected area occurred inside the protected area this would have resulted in reductions in daily streamflow leaving the protected portion of the catchment. For example, outside the protected area reductions of 8% to 25% of streamflow were observed during mid and low flow conditions respectively, particularly during dry years, in comparison to a ‘natural’ scenario. In contrast, inside the protected area streamflow recovered from past conditions to more closely resemble the natural flow conditions of the catchment. Therefore, had the protected area not been established there would have been losses in streamflow from the catchment as well as an increase in the degree of fragmentation within this mountain area. However, with increased water storage and fragmentation outside the protected area has also come increased socio-economic opportunities such as employment and local opportunities for ecotourism and sustainable agriculture e.g. indigenous cut flows. This highlights the importance of maintaining various forms of land management systems (multifunctional landscapes) within mountain ecosystems but also the need to understand the sustainability of different land management system types. Determining appropriate land management systems for mountain areas should be based on a full understanding of the impacts on ecosystem service benefits and costs at local and regional levels between social groups both spatially and temporally. Broader significance: This thesis contributes to the conservation literature on two main fronts. Firstly, it contributes conceptually and theoretically to understanding the dynamics of ecosystem services in relation to mountain protection. Secondly, it contributes methodologically by using an inclusive, trans- and interdisciplinary research approach for evidence-based conservation at a place-based and landscape level. The study provides a case 6 study example of the positive impact that mountain protection has on water-related ecosystem services, notably by maintaining streamflow throughout high to low flow periods and during dry years. It also provides clear evidence that ecosystem service trade-offs do not remain constant over time and shows that intrinsic and non-use values are required when describing the importance of mountain protected areas. In terms of understanding the impact that protected areas have in mountain regions, the research shows that complex processes are at play that extend beyond the boundaries of a specific protected area in both time and space. Interactions between global and local drivers were found to be prominent causal mechanisms of socio-ecological change and ultimately determined the influence of mountain-protection on land use/cover, fire, vegetation and water-related ecosystem services. The thesis emphasises that counterfactual framings are necessary to understand and attribute the impacts of protected areas on environmental outcomes, however pluralism and socio-ecological approaches are critical to determine plausible counterfactual conditions. This thesis focused only on landowners adjacent and proximal to the protected area owning the majority of mountain catchment land of similar terrain. It is likely that multiple socioeconomic trade-offs have occurred between different social groups and generations at both local and regional levels. Understanding how the disadvantages and benefits of the impacts of protected areas are apportioned across the landscape and temporally is an aspect that requires future research. Central to this would be to fully consider how human well-being is influenced both upstream and downstream, including at regional levels, and between social groups and across generations. Considering the impact of protected areas on the full range of ecosystem services and linking this to societal preferences and perceptions should be incorporated into the overall goal of developing an evidence base for conservation. This is because it is both scientific evidence and societal change that can determine protected area persistence and thus long-term protected area impact.
76

Retraining the Brain to Prevent Disordered Eating: Approach Versus Avoidance

Jones, Maegan Elizabeth January 2019 (has links)
Emerging adult college women are at particular risk for developing unhealthy eating habits. Despite this, methods of intervention in this population are understudied. This study sought to test whether an implicit, cognitive retraining program could alter how women approach foods. Specifically, the researcher wanted to determine if the Behavioral Activation System (BAS), which encourages individuals to approach positive goals, and the Behavioral Inhibition System (BIS), which helps individuals avoid negative outcomes, could be manipulated. Thus, this study examined whether a dot-probe retraining program could significantly alter women’s approaches to healthy foods. Dot-probe programs present two pictures side-by-side; when the pictures disappear, a stimulus, in this case a “+”, appears where one of the pictures was previously located. In this project, participants assigned to an experimental training program would have the “+” located under healthy foods most of the time, in order to encourage BAS activation and approach behaviors. In addition, because it is imperative to understand how women’s families affect their thin ideal internalization (i.e., drive for thinness and restraint) and their approach/avoidance habits, the quality of past and current parent-daughter relationships were examined. Indeed, no known research has examined how the parent-child relationship may affect BAS/BIS usage. Forty emerging adult women were recruited; half were assigned to an experimental training group, while the other half completed a sham training group, in which they equally reacted to all foods. Participants were asked to complete five sessions on their own devices, in their chosen environment. By the final training sessions, those in the experimental group (n = 15) reacted to healthy foods two times faster than those in the sham group (n = 15). In addition, a series of moderation analyses found that, even when participants had high levels of thin ideal internalization, positive parenting characteristics such as a current high-quality mother-daughter relationship and past low paternal control improved participants’ reaction times to healthy foods. These findings suggest that a combination of both a biologically-based method of intervention and a family systems intervention may lead women to have healthier approaches to foods, thereby potentially preventing the development of unhealthy eating habits.
77

Impact of Migration on Welfare of Migrant Sending Households in Selected Rural Areas of Zimbabwe

Zvendiya, Ronald 29 March 2022 (has links)
The New Economics of Labour Migration theory, recognizes family participation in migration decisions as a strategy for moving out of poverty, thus signaling potential welfare linkages between migrants and family members left behind. The current study investigates the impact of migration on welfare of migrant sending households in rural Zimbabwe using cross-sectional data. The study employed a Counterfactual approach and utilized two stage Heckman selection model to control for selection bias. The results indicated that on average, migration impacts household welfare positively but the welfare gains are not evenly distributed among households. Overall, the welfare of households with migrants would have been 5 percentage points lower if migrant members had stayed at home. Based on the findings, the main recommendation is that policy makers need to consider the removal of de facto and de jure migration restrictions.
78

Congestion control in packet switch networks

Kamga, Morgan 10 December 2008 (has links)
We consider a congestion control problem in computer networks. The problem is posed as an optimal control problem and reduced to a problem of finding solutions to delay differential equations. Systems involving time delays in the dynamics are actually very difficult to model and therefore very difficult to solve. We consider three approaches in our congestion control problem: an elastic queue approach leading to an optimal control problem with a state–dependent delay differential equation; three approaches in flow models (also leading to systems containing delay differential equations), precisely the dual control approach, the primal–dual control approach and the control approach based on queueing delay. The elastic queue approach is not explored due to the lack of software good enough to solve optimal control problems involving delay differential equations. In flow models, we consider the standard case, that is where the feedback from sources to links is exact and the network behaves perfectly well (without any unexpected event). We also consider some non–standard cases such as the case where this feedback contains errors (for example overestimation, underestimation or noise), and the case where one link breaks in the network. We numerically solve the delay differential equations obtained and use the results we get to determine all the considered dynamics in the network. This is followed by an analysis of the results. We also explore the stability of some simple cases in the dual control approach, with weaker conditions on some network parameters, and discuss some fairness conditions in some simple cases in all the flow model approaches. Non–standard cases are also solved numerically and the results can be compared with those obtained in the standard case.
79

A Hybrid Classifier Committee Approach for Microarray Sample Classification

Vishnampettai Sridhar, Aadhithya 17 August 2011 (has links)
No description available.
80

An Intersectional Approach to the Study of Sexual Stigma

Fredrick, Emma G., Williams, Stacey L. 02 April 2014 (has links)
Sexual minorities report experiencing more stigma, fewer psychosocial resources, and less positive regard. While differences within sexual minority subgroups may exist in terms of both experience and attitudes, the current literature lacks an exploration of those differences as well as an exploration of intersectionality (the concept of belonging to multiple minority groups thus creating a novel and distinctive experience). Our study aimed to examine sub-group differences as well as take an intersectional approach using data on heterosexuals, homosexuals, and bisexuals (N=1,725) from across the U.S. Bisexuals differed significantly from homosexuals on reported experiences, such as higher outness (p<.001, MD=-0.573). Further, significant differences were found between female (n=106) and male (n=136) homosexuals with lesbians reporting less direct help-seeking (t=-2.255, p=.026) and less perceived social support (t=-2.014, p=.046) than gay men, indicating that the intersection of gender and sexual orientation creates a novel experience for each group. These findings along with the lack of racial diversity lead us to conclude that a more extensive study must be done that targets racial minority individuals and expands the intersectional framework by including more gender and sexual orientation options. A full spectrum intersectionality study will be proposed.

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