Global ETD Search

131	Efficient Semi-Implicit Time-Stepping Schemes for Incompressible Flows Loy, Kak Choon January 2017 (has links) The development of numerical methods for the incompressible Navier-Stokes equations received much attention in the past 50 years. Finite element methods emerged given their robustness and reliability. In our work, we choose the P2-P1 finite element for space approximation which gives 2nd-order accuracy for velocity and 1st-order accuracy for pressure. Our research focuses on the development of several high-order semi-implicit time-stepping methods to compute unsteady flows. The methods investigated include backward difference formulae (SBDF) and defect correction strategy (DC). Using the defect correction strategy, we investigate two variants, the first one being based on high-order artificial compressibility and bootstrapping strategy proposed by Guermond and Minev (GM) and the other being a combination of GM methods with sequential regularization method (GM-SRM). Both GM and GM-SRM methods avoid solving saddle point problems as for SBDF and DC methods. This approach reduces the complexity of the linear systems at the expense that many smaller linear systems need to be solved. Next, we proposed several numerical improvements in terms of better approximations of the nonlinear advection term and high-order initialization for all methods. To further minimize the complexity of the resulting linear systems, we developed several new variants of grad-div splitting algorithms besides the one studied by Guermond and Minev. Splitting algorithm allows us to handle larger flow problems. We showed that our new methods are capable of reproducing flow characteristics (e.g., lift and drag parameters and Strouhal numbers) published in the literature for 2D lid-driven cavity and 2D flow around the cylinder. SBDF methods with grad-div stabilization terms are found to be very stable, accurate and efficient when computing flows with high Reynolds numbers. Lastly, we showcased the robustness of our methods to carry 3D computations. time-stepping Navier-Stokes equations finite element method Taylor-Hood elements high-order 2D/3D unsteady flows semi-implicit grad-div stabilization defect correction sequential regularization method artificial-compressibility flow around the cylinder lid-driven cavity
132	Komparace redistribuce příjmů prostřednictvím dávek státní sociální podpory v České republice a Velké Británii / Comparison of income redistribution through state social support benefits in the Czech Republic and Great Britain Trávníčková, Jana January 2010 (has links) The thesis is focused on the exploration of income inequality among citizens of the Czech Republic and Great Britain. It is a comparison that evaluates the state income redistribution through state social support benefits. It provides information, in which country exists greater income inequality in income distribution among households and whether the income inequality among the citizens decreased due to the payment of these benefits or not. The theoretical parts of the work are devoted to explanation of basic terms (such as income redistribution, instruments of redistribution, relationship between social policy and redistribution) and tools for measuring income inequality (Lorenz curve, Gini coefficient, Robin Hood index, Interquintile share ratio S80/S20). The text also describes the various state social support benefits of both countries. The main research section contains calculations and graphical representations of all the above mentioned indicators. The final values are compared and the results are summarized.
133	THE IMPACT OF MELTING GLACIERS ON MOUNTAIN GROUNDWATER SYSTEMS: A MULTI-YEAR STUDY INCORPORATING ISOTOPIC TRACERS AND MICROBIOLOGY IN MOUNT HOOD NATIONAL FOREST, OREGON, AND GLACIER NATIONAL PARK, MONTANA, AND TIME SERIES ANALYSES IN THE SWISS ALPS Jordyn B Miller (11852195) 17 December 2021 (has links) <p>Alpine glaciers around the world are in retreat and are unlikely to reverse course. This dissertation focuses on improving our understanding of the impact of glacial melt on mountainous alpine groundwater systems. Studies on glacial melt-groundwater interactions have become more prevalent, particularly in the past 5 years, because we are recognizing that the contribution of glacial melt to the hydrologic cycle is not limited to melt-season surficial streamflow. The importance of glacial melt to mountain groundwater systems has the potential to not only influence spring and streamflow generation, but also the longevity of alpine specific, and frequently endangered species, dependent on this source of recharge. This recharge may be vital for human water needs such as potable water, agriculture, and hydrothermal power.</p>The impact that a transition from glacial melt to snow- or rain-dominated streamflow and recharge will have on alpine ecosystems in a continually warming climate is far reaching. This dissertation: 1) tests whether glacial melt is an important source of recharge for mountain springs and their microbial communities, 2) investigates the spatial impact of glacial-melt recharge on residence times and flowpaths that support alpine springs, and 3) explores the impact of post-peak water on alpine baseflow using a statistical, timeseries approach. My results show that the groundwater systems in glaciated mountainous, alpine regions are particularly vulnerable to climate change. Springs in Mount Hood National Forest and Glacier National Park were sampled over a 4-year period, and in addition, publicly available long-term streamflow datasets were are also utilized. The chapters composing this work build upon each other, and compare and contrast the factors most important in glacial melt recharging the mountain-block. Information that is vital to the management of alpine water resources by landowners, watershed groups, scientists, and others interested in mountain groundwater systems in glaciated alpine regions is presented in the following pages. Geology Environmental Science Hydrology Climate Science Isotope Geochemistry Geochronology Glaciology Hydrogeology Surface Processes Surfacewater Hydrology groundwater glacier climate change isotope mountain groundwater melting glaciers glacier national park mount hood national forest swiss alps glacial retreat
134	Vliv polohy zesíleného štěrbinového sacího nástavce nad pracovním stolem na účinnost odsávání / Influence of location of reinforced slot exhaust hood above work table on capture efficiency Winkler, Martin January 2012 (has links) The present thesis explores the reinforced exhaust slot system above work table. Its objective was to measure the capture efficiency in front of the suction extension in various elevation levels of the workbench, taking into consideration four mobility ratios, while in the first case we performed traditional suction. The thesis also presents the results of capture efficiency measurements recorded in figures and tables of measured values. The conclusion analyzes the uncertainty in performed measurements.
135	Understanding Participation in Wildlife Conservation Programs on Private Lands Sorice, Michael G. 14 January 2010 (has links) One major lesson derived from the implementation of the Endangered Species Act (ESA) over the past 30 years is that direct regulation is not the only nor the optimal way to protect endangered species on working lands because of an undue burden imposed on private landowners. The role of a voluntary conservation program is to rearrange incentives so that society bears the cost rather than the landowner. Employing a survey research methodology, I used theories of reasoned action and random choice to explore landowners? stated preferences for conservation programs. I found landowners? stated interest in compensation programs to be moderate at best. For those willing to consider programs involving endangered species, associating land management requirements for species conservation with direct benefits to the landowner is important, but perhaps not as important as ensuring that the program provides adequate financial incentives, consideration of the term of the program, and a level of certainty regarding the landowner?s future obligations under the ESA. Landowners are not a homogenous group. I identified two classes of landowners according to preferences for program structure. One group was highly sensitive to program structure, aside from financial incentives, while the other was likely to participate if adequately compensated with financial and technical assistance. These differences related to opinions on endangered species protection and dependence on their land for income. Voluntary incentive programs increasingly are a popular tool to maintain and enhance conservation; however, these programs are only successful insofar as landowners choose to enroll. This research demonstrates that improving recovery efforts on private lands requires program administrators to have a more complete understanding of landowners? views on endangered species and conservation programs in general, as well as their motivations for owning and operating their land. By doing so, programs with broader appeal and greater efficacy can be designed and implemented. endangered species human dimensions incentive programs private lands landowners decision making conservation endangered species act black-capped vireo golden-cheeked warbler ranchers theory of reasoned action stated preference choice model choice experiment biodiversity wildlife management non-game wildlife texas fort hood recovery credit system
136	Barns medierade värld : syskonsamspel, lek och konsumtion / Children's mediated world : Sibling interaction, play and consumption Ågren, Ylva January 2015 (has links) This thesis focuses on sibling interaction and children’s everyday media practices in their homes. Ten sibling pairs, aged four to nine years, have been followed in their homes during a six-month period with media ethnographic methods. The data mainly consist of video recorded sibling interactions. The thesis draws on sociocultural theories, cultural sociological perspectives and insights from social interaction research. The analyses are grounded in the social interaction and meaning making acts that take place in media activities in the home settings. However they also extend to a broader societal context, in order to show how social structure and social action are constantly interwoven in children’s lives. The thesis documents how the media represent an important part of the child's everyday culture. Media create key reference frames and common platforms for the children’s games and play activities. The siblings use media and various artifacts to negotiate, challenge or assume desirable positions. Media artefacts can also be used as a way to present oneself. The younger siblings progressively work their way into the older siblings’ media landscapes, and the elder siblings become guides or role models in handling video games, music, and YouTube activities. In addition to purely practical skills when it comes to handling the technical equipment, the older siblings also mediate local taste hierarchies, norms, and values. The thesis also describes how children are social actors who interpret and reinterpret the constant ongoing movements in the media landscape. Moreover, the thesis highlights how consumption is closely linked to media practices. Mobiles, games consoles and membership on virtual gaming sites become highly valued phenomena and status markers in children’s media worlds. / Detta arbete undersöker hur syskon samspelar och skapar mening och social ordning inom ramen för olika mediepraktiker. Med hjälp av medieetnografiska metoder har 14 barn i åldrarna fyra till nio år (tio olika syskonkonstellationer) följts i hemmiljö under en halvårsperiod. Materialet består främst av videoinspelad interaktion. Avhandlingen bygger på sociokulturella och kultursociologiska perspektiv, där individen ses som en aktiv, meningsskapande och samspelande aktör som påverkar och påverkas av sin sociala och kulturella kontext. Analysen är i huvudsak relaterad till de handlingar som äger rum i lokalt situerade aktiviteter och undersöker vad syskonen gör med medier i olika verksamheter, men visar även hur samhällelig kontext och barns aktörskap är parallella aspekter i barns liv. Avhandlingen synliggör hur medier utgör en stor och viktig del av barns vardagskultur. Medier är självklara referensramar och skapar gemensamma plattformar för barnens samtal och lekar. Syskonen använder medier och olika artefakter för att förhandla, utmana eller fördela positioner. Småsyskonen tar sig successivt in i de äldre syskonens medielandskap, medan de äldre ofta blir ledstjärnor eller ger sig själva tolkningsföreträde. Vidare visas hur kunskapsförmedling är ett väsentligt inslag mellan syskon. Utöver rent praktiska färdigheter i hur de tekniska apparaterna ska hanteras, förhandlas även smak, normer, värderingar och tillgång till symboliskt kapital. Spel, musik, TV, YouTube och medieartefakter används som resurser för självpresentation. Analyserna pekar på barnens aktörskap; barnen tolkar, omtolkar, utmanar och förhandlar innebörder och föreställningar om vad som är kultur för barn. Avhandlingen belyser även hur konsumtion intimt hänger samman med mediepraktiker. Mobiler, spelkonsoler och medlemskap på virtuella spelsidor blir åtråvärda artefakter och statusmarkörer i barnens medievärldar. social interaction meaning making positionings siblings age generation mediatization media computer games play practices consumption communities of practice cultural capital taste negotiations child-hood studies barnkultur aktörskap social interaktion meningsskapande positioneringar syskonskap åldersordning medialisering medier datorspel lek musik TV konsumtion praktikgemenskap kulturellt kapital smak förhandlingar
137	Komparace daňové zátěže zaměstnanců v ČR a v Rakousku / Comparison of the tax burden of employees in the Czech Republic and in Austria Krčmářová, Simona January 2014 (has links) This master´s thesis compares a taxation of employment in the Czech Republic and in Austria. The effective tax rate and the effective rate of the total burden employee analyzes the tax burden on emplyee for various types of taxpayers. The next chapter examines the interval progressivity of taxes in both states and it evaluates, for which taxpayers a degree of progressivity of the income tax is the most sensitive. Lorenz curve before and after taxation in the last chapter shows the distribution of income between employees and the impact of taxation in order to redistribute the income in society. Coefficients compiled from the Lorenz curve for the Czech Republic and Austria quantify the degree of income redistribution through a progressive income tax.
138	Modélisation et simulation numérique de matériaux à changement de phase. / Numerical simulation and modelling of phase-change materials Rakotondrandisa, Aina 27 September 2019 (has links) Nous développons dans ce travail de thèse un outil de simulation numérique pour les matériaux à changement de phase (MCP), en tenant compte du phénomène de convection naturelle dans la phase liquide, pour des configurations en deux et trois dimensions. Les équations de Navier-Stokes incompressible avec le modèle de Boussinesq pour la prise en compte des forces de flottabilité liées aux effets thermiques, couplées avec une formulation de l’équation d’énergie suivant la méthode d’enthalpie, sont résolues par une méthode d’éléments finis adaptatifs. Une approche mono-domaine, consistant à résoudre les mêmes systèmes d’équations dans les phases solide et liquide, est utilisée. La vitesse est ramenée à zéro dans la phase solide, en introduisant un terme de pénalisation dans l’équation de quantité de mouvement, suivant le modèle de Carman-Kozeny, consistant à freiner la vitesse à travers un milieu poreux. Une discrétisation spatiale des équations utilisant des éléments finis de Taylor-Hood, éléments finis P2 pour la vitesse et éléments finis P1 pour la pression, est appliquée, avec un schéma d’intégration en temps implicite d’ordre deux (GEAR). Le système d’équations non-linéaires est résolu par un algorithme de Newton. Les méthodes numériques sont implémentées avec le logiciel libre FreeFem++ (www.freefem.org), disponible pour tout système d’exploitation. Les programmes sont distribués sous forme de logiciel libre, sous la forme d’une forme de toolbox simple d’utilisation, permettant à l’utilisateur de rajouter d’autres configurations numériques pour des problèmes avecchangement de phase. Nous présentons dans ce manuscrit des cas de validation du code de calcul, en simulant des cas tests bien connus, présentés par ordre de difficulté croissant : convection naturelle de l’air, fusion d’un MCP, le cycle complet fusion-solidification, chauffage par le bas d’un MCP, et enfin, la solidification de l’eau. / In this thesis we develop a numerical simulation tool for computing two and three-dimensional liquid-solid phase-change systems involving natural convection. It consists of solving the incompressible Navier-Stokes equations with Boussinesq approximation for thermal effects combined with an enthalpy-porosity method for the phase-change modeling, using a finite elements method with mesh adaptivity. A single-domain approach is applied by solving the same set of equations over the whole domain. A Carman-Kozeny-type penalty term is added to the momentum equation to bring to zero the velocity in the solid phase through an artificial mushy region. Model equations are discretized using Galerkin triangular finite elements. Piecewise quadratic (P2) finite-elements are used for the velocity and piecewise linear (P1) for the pressure. The coupled system of equations is integrated in time using a second-order Gear scheme. Non-linearities are treated implicitly and the resulting discrete equations are solved using a Newton algorithm. The numerical method is implemented with the finite elements software FreeFem++ (www.freefem.org), available for all existing operating systems. The programs are written and distributed as an easy-to-use open-source toolbox, allowing the user to code new numerical algorithms for similar problems with phase-change. We present several validations, by simulating classical benchmark cases of increasing difficulty: natural convection of air, melting of a phase-change material, a melting-solidification cycle, a basal melting of a phase-change material, and finally, a water freezing case. Navier-Stokes Boussinesq Méthode d'enthalpie mono-domaine Carman-Kozeny Eléments finis FreeFem++ Maillage adaptatif Matériaux à changement de phase (MCP) Convection naturelle Algorithme de Newton Fusion Cycle complet Solidification de l'eau Navier-Stokes Boussinesq Enthalpy-porosity method Carman-Kozeny Finite elements Taylor-Hood FreeFem++ Mesh adaptivity Phase-change materials (PCM) Natural convection Newton algorithm GEAR scheme Open-source toolbox 2D and 3D simulations Melting Solidification Water freezing 511.8
139	My Journey with Prisoners: Perceptions, Observations and Opinions Briney, Carol E. 08 July 2013 (has links) No description available. African American Studies African Studies Aging Art Criticism Art Education Behavioral Psychology Behavioral Sciences Black History Black Studies Cognitive Psychology Cognitive Therapy Communication Counseling Education Counseling Psychology Criminology Cultural Anthropology Cultural Resources Management Curriculum Development Developmental Psychology Divinity Early Childhood Education Education Education Philosophy Educational Psychology Educational Evaluation Educational Sociology Educational Tests and Measurements Elementary Education Evolution and Development Experimental Psychology Families and Family Life Fine Arts Forensic Anthropology Gender Studies Gerontology Individual and Family Studies Inservice Training Instructional Design Journalism Kinesiology Language Linguistics Literacy Logic Mental Health Metaphysics Minority and Ethnic Groups Modern History Modern Literature Occupational Psychology Organizational Behavior Pastoral Counseling Peace Studies Pedagogy Personal Relationships Personality Psychology Philosophy Political Science Psychology Psychotherapy Public Administration Public Policy Religion Religious Education School Counseling Secondary Education Social Psychology Social Research Social Structure Social Work Sociolinguistics Sociology Spirituality Teacher Education Theology Urban Planning Vocational Education Welfare Womens Studies prison reentry trauma poverty grounded theory universal value punitive recidivism corrections Retablo play therapy male prisoners female prisoners socio-metaphysics grief-impairment grief and loss truth-telling poverty hood prison art
140	The Social Construction of Economic Man: The Genesis, Spread, Impact and Institutionalisation of Economic Ideas Mackinnon, Lauchlan A. K. Unknown Date (has links) The present thesis is concerned with the genesis, diffusion, impact and institutionalisation of economic ideas. Despite Keynes's oft-cited comments to the effect that 'the ideas of economists and political philosophers, both when they are right and when they are wrong, are more powerful than is commonly understood'(Keynes 1936: 383), and the highly visible impact of economic ideas (for example Keynesian economics, Monetarism, or economic ideas regarding deregulation and antitrust issues) on the economic system, economists have done little to systematically explore the spread and impact of economic ideas. In fact, with only a few notable exceptions, the majority of scholarly work concerning the spread and impact of economic ideas has been developed outside of the economics literature, for example in the political institutionalist literature in the social sciences. The present thesis addresses the current lack of attention to the spread and impact of economic ideas by economists by drawing on the political institutionalist, sociological, and psychology of creativity literatures to develop a framework in which the genesis, spread, impact and institutionalisation of economic ideas may be understood. To articulate the dissemination and impact of economic ideas within economics, I consider as a case study the evolution of economists' conception of the economic agent - "homo oeconomicus." I argue that the intellectual milieu or paradigm of economics is 'socially constructed' in a specific sense, namely: (i) economic ideas are created or modified by particular individuals; (ii) economic ideas are disseminated (iii) certain economic ideas are accepted by economists and (iv) economic ideas become institutionalised into the paradigm or milieu of economics. Economic ideas are, of course, disseminated not only within economics to fellow economists, but are also disseminated externally to economic policy makers and business leaders who can - and often do - take economic ideas into account when formulating policy and building economic institutions. Important economic institutions are thereby socially constructed, in the general sense proposed by Berger and Luckmann (1966). But how exactly do economic ideas enter into this process of social construction of economic institutions? Drawing from and building on structure/agency theory (e.g. Berger and Luckmann 1966; Bourdieu 1977; Bhaskar 1979/1998, 1989; Bourdieu 1990; Lawson 1997, 2003) in the wider social sciences, I provide a framework for understanding how economic ideas enter into the process of social construction of economic institutions. Finally, I take up a methodological question: if economic ideas are disseminated, and if economic ideas have a real and constitutive impact on the economic system being modelled, does 'economic science' then accurately and objectively model an independently existing economic reality, unchanged by economic theory, or does economic theory have an interdependent and 'reflexive' relationship with economic reality, as economic reality co-exists with, is shaped by, and also shapes economic theory? I argue the latter, and consider the implications for evaluating in what sense economic science is, in fact, a science in the classical sense. The thesis makes original contributions to understanding the genesis of economic ideas in the psychological creative work processes of economists; understanding the ontological location of economic ideas in the economic system; articulating the social construction of economic ideas; and highlighting the importance of the spread of economic ideas to economic practice and economic methodology. 410401 Design Theory 349901 Political Economy 370000 Studies in Human Society 340302 History of Economic Thought 349900 Other Economics 410402 Design Innovation 360201 Public Policy 360000 Policy and Political Science 380100 Psychology 360100 Political Science 360200 Policy and Administration 370101 Social Theory 370102 Social Policy and Planning 340100 Economic Theory genesis spread diffusion impact institutionalisation economic ideas idea ideation psychology of creativity Wallas Wertheimer stage model productive thinking creative creativity process economic economics sociology social methodology methodological self-altering self-fulfilling self-denying prophecy belief reflexive reflexivity institution institutionalise institutionalised social construction Berger Luckmann Bhaskar critical realism Lawson Bordieu habitus field spread impact ideation ideational structure social structure action creativity creative economists sociology philosophy of science homo economicus homo oeconomicus economic man economic agent rational economic man man lucas critique Goodhart's law Keynes Marx Mill Hayek Hicks Samuelson Walras Jevons Arrow Debreu Samuelson Merton sociology of economics sociology of scientific knowledge SSK Holton prediction control reflexive prediction reflexivity Whitley Mackie canonization Henshel Grunberg Modigliani Morgenstern Lucas Muth Simon Blyth Hall Sikkink Hira Hood institutionalize institutionalized socialise socialisation internalise internalisation internalization socialization behaviour behavior Thomas theorem expectations stage model productive thinking evolution

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