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Arbesu, Ramon A. "Boundary : an exploration of architecture's power to mark a boundary." FIU Digital Commons, 2002. http://digitalcommons.fiu.edu/etd/1345.
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Cities are no longer recognizing their boundaries beyond their legal or political implications. This thesis explored the architecture of a boundary in the design of a structure that visually and symbolically marked the current Miami-Dade County development limit along Krome Avenue. This limit ultimately separates the city from the endangered Everglades ecosystem. Through the examination of ancient boundaries such as Medieval and Renaissance Military fortifications, as well as contemporary interventions such as Steven Holl's "Edge of the City Projects", an architectural vocabulary was developed considering the Double Wall, Bastion, Rampart, and Gate principles. However, rather than considering these principles to defend the city from outside forces, the focus of this exploration is their inversion in order to contain the city by strengthening its periphery visually and symbolically. From this exploration, it was concluded that a successful boundary or limit should be visible and significant. Furthermore, it should serve as an informative and reflective landmark.
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Velde, Antoine van de. "A multidimensional boundary sources method." Doctoral thesis, Universite Libre de Bruxelles, 1994. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212674.
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Dullaway, Scott N. M. "A VHF boundary-layer radar /." Title page, contents and abstract only, 1999. http://web4.library.adelaide.edu.au/theses/09SM/09smd883.pdf.
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Furulind, Johanna, and Olivia Sjöqvist. "The Uber Boundary : Contextualizing the Organizational Boundary of a Digital Platform Organization." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-388921.
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Digital platform organizations challenges the organizational landscape by utilizing technology enabling cost efficient transactions. Uber is a commonly known example of such an organization, where tensions have arisen in various local contexts due to that the organization draw their boundary tightly around the platform to the benefit of organizational efficiency. Uber has as a consequence, been highly questioned in its liability of their primary operations: Is it a technology platform, or a transportation firm? This thesis sets out to answer: How is the organizational boundary of Uber challenged in various local contexts? The purpose is to provide an explanation towards how the organizational boundary of a digital platform organization could be understood in relation to local context, and how it can or cannot evolve in regards to these contexts. The results show that context matters for the boundary of Uber. In addition, a pattern amongst the context specific events emerged influencing the boundary. These can be categorized into four configurations: Adjusting, Expanding, Withdrawing and Intertwining. Each of the configurations explain the underlying reasons for the varying fluctuations the boundary of Uber show, and thus answer how the organizational boundary of Uber is challenged in various local contexts.
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Fure, Ashley Rose. "Boundary Notions: A Sonic Art Portfolio." Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:10962.
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I offer this dissertation as a survey and a story: a survey of my work across the field of sonic art and a story of my progressive compulsion toward sound that conveys touch. This haptic sensibility sharpens from Susurrus (2006) through Soma (2012), manifesting in a fixation on the impact of sound on bodies and the impact of bodies on sound. Both the visceral sensation of hearing and the manner in which movement imprints onto acoustic phenomena concern me. My musical forms are conceived not as abstract arrangements of objects (or notes) but as complex physical confrontations that produce audible byproducts. I compose primarily with chaotic spectra, mixing raw noise from found objects with extended instrumental techniques. These timbres front an acoustic wildness intentionally abated in conventional instrumental practice. And yet, the precision of classical instruments opens avenues of transformation closed to unmediated noise. Virtuosity and crudeness face-off in my work, circling an aesthetic region between embellishment and fact, between sound as a carrier of aesthetic intent and sound as a subsidiary effect of action. The ten works presented in this portfolio include eight compositions scored for a range of ensembles, from soloist to orchestra, with and without electronics, as well as two interactive multimedia installations. Dramatic links between physical movement and musical form arise across this output. In my installations, I posit causal relationships between visible stimuli (spinning strings, spatial structures, moving bodies) and resultant sounds. In my electroacoustic works, I attend to the implied weight of spatialized sound – as though a gesture’s trajectory through arrayed speakers were informed by gravity. In my acoustic music, I bring the muscular strain behind instrumental technique to the perceptual fore. My professional activities shift regularly between concert music and installation art and between acoustic and electroacoustic contexts. Passing between these genres stretches the boundaries of my creative practice and forces me to consistently reframe notions of ritual and form. Within each platform, I aim to stage visceral aesthetic encounters that, as Francis Bacon once hoped for his paint, bypass the brain and go directly to the nervous system.Music
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Harrison, Jonathan. "Boundary strategy : a new sociological model." Thesis, University of Leicester, 2006. http://hdl.handle.net/2381/29010.
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This thesis is a work of historical sociology, presenting a developmental model of the British State that tracks its growth as a strategic system since 1066. It is comparable with the work of Mann (1986) and Tilly (1992) in arguing for a long-term model of state development that focusses on elite strategies. Boundary strategy is defined as a field of strategic action, with the state at its centre, which helps to produce a national population that imagines its internal boundaries of 'race', ethnicity, class and location in ways that conceal the objective structure of political and class relations. The thesis demonstrates how this field has developed in Britain over the centuries into six key strategies, defined as Blood, Pollution, Property, Civilisation, Nation and Race. The study achieves this by dividing British history since 1066 into four phases. The first is the Feudal State, 1066-1529. The second is the Protestant State, 1530-1829. The third is the Incorporation State, 1830 to the present day, and the fourth is the Fortress State, 1903 to the present day. It is argued that the Incorporation and Fortress phases of the state's development have unfolded concurrently since 1903, forming two distinct but interdependent functional dimensions. The thesis devotes one case study chapter to each phase. The final case study chapter then examines how the incorporation and fortress dimensions have been synthesised in the policy of asylum seeker dispersal since 1997. Each study is structured around the strategies and investigates how the strategies have responded to conflicts between elite interests and popular pressures 'from below'. The case studies also examine how popular violence against minorities has resulted from the unintended consequences of boundary strategies.
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Ademoyero, Oreoluwa Oyinlade. "A parallel Galerkin boundary element method." Thesis, University of Hertfordshire, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410144.
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Tang, W. "A generalized approach for transforming domain integrals into boundary integrals in boundary element methods." Thesis, University of Southampton, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378981.
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Zhang, Cheng. "Continuous and quad-graph integrable models with a boundary : reflection maps and 3D-boundary consistency." Thesis, City University London, 2013. http://openaccess.city.ac.uk/3016/.
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This thesis is focusing on boundary problems for various classical integrable schemes. First, we consider the vector nonlinear Schrodinger (NLS) equation on the halfline. Using a Backlund transformation method which explores the folding symmetry of the system, classes of integrable boundary conditions (BCs) are derived. These BCs coincide with the linearizable BCs obtained using the unified transform method developed by Fokas. The notion of integrability is argued by constructing an explicit generating function for conserved quantities. Then, by adapting a mirror image technique, an inverse scattering method with an integrable boundary is constructed in order to obtain N-soliton solutions on the half-line, i.e. N-soliton reflections. An interesting phenomenon of transmission between different components of vector solitons before and after interacting with the boundary is demonstrated. Next, in light of the fact that the soliton-soliton interactions give rise to Yang-Baxter maps, we realize that the soliton-boundary interactions that are extracted from the N-soliton reflections can be translated into maps satisfying the set-theoretical counterpart of the quantum reflection equation. Solutions of the set-theoretical reflection equation are referred to as reflection maps. Both the Yang-Baxter maps and the reflection maps guarantee the factorization of the soliton-soliton and soliton-boundary interactions for vector NLS solitons on the half-line. Indeed, reflection maps represent a novel mathematical structure. Basic notions such as parametric reflection maps, their graphic representations and transfer maps are also introduced. As a natural extension, this object is studied in the context of quadrirational Yang-Baxter maps, and a classification of quadrirational reflection maps is obtained. Finally, boundaries are added to discrete integrable systems on quad-graphs. Triangle configurations are used to discretize quad-graphs with boundaries. Relations involving vertices of the triangles give rise to boundary equations that are used to described BCs. We introduce the notion of integrable BCs by giving a three-dimensional boundary consistency as a criterion for integrability. By exploring the correspondence between the quadrirational Yang-Baxter maps and the so-called ABS classification, we also show that quadrirational reflection maps can be used as a systematic tool to generate integrable boundary equations for the equations from the ABS classification.
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McGregor, Peter Stanley. "Modelling the Effect of Suspended Bodies on Cavitation Bubbles near a Ridgid Boundary using a Boundary Integral Approach." Queensland University of Technology, 2003. http://eprints.qut.edu.au/15822/.
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Cavitation is the spontaneous vaporisation of a liquid to its gaseous state due to the local absolute pressure falling to the liquid's vapour pressure (Douglas, Gasiorek et al. 1995). Cavitation is present in a wide range of mechanical systems ranging from ship screws to journal bearing. Generally, cavitation is unavoidable and may cause considerable damage and efficiency losses to these systems. This thesis considers hydraulic systems specifically, and uses a modified Greens equation to develop a boundary integral method to simulate the effect that suspended solid bodies have on a single cavitation bubble. Because of the limitations of accurately modelling cavitation bubbles beyond touchdown, results are only presented for cases up to touchdown. The aim of the model is to draw insight into the reasons there is a measurable change in cavitation erosion rate with increasing oil-in-water emulsion percentage. This principle was extended to include the effect that ingested particulates may have on cavitation in hydraulic machinery. Two particular situations are modelled; the first consists of stationary rigid particles in varying proximity to a cavitation bubble near a rigid boundary. The second case is similar; however the suspended particle is allowed to move under the influence of the pressure differential caused by the expanding/contracting cavitation bubble. Numerous characteristics of the domain are considered, including domain pressures and fluid field motion, and individual boundary surface characteristics. The conclusion of the thesis is that solid bodies, either stationary or moving, have little effect on the cavity from an energy perspective. Regardless of size or density, all energy transferred from the cavity to the solid body is returned indicating that there is no net change. As this energy is ultimately responsible for the peak pressure experienced by the domain (and hence responsible for eroding the rigid boundary) as the cavity rebounds, it then serves that a cavity with a solid body will rebound at the same pressure as a cavity without a suspended body present. If this is coupled with the observation that the cavity centroid at touchdown is largely unaffected by the presence of a suspension, then it would appear that the bubble near a solid would rebound at a very similar position as a cavity without a solid. Consequently, the damage potential of a cavity is unaffected by a suspension. However, there is one point of contention as the profile of the re-entrant jet of the cavity is altered by the presence of a suspension. As energy is radiated away from the cavity during penetration, it is possible that the shape of the jet may alter the rate that energy is radiated away during penetration. However, this requires further research to be definitive.
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McGregor, Peter Stanley. "Modelling the effect of suspended bodies on cavitation bubbles near a rigid boundary using a boundary integral approach." Thesis, Queensland University of Technology, 2003. https://eprints.qut.edu.au/15822/1/Peter_McGregor_Thesis.pdf.
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Cavitation is the spontaneous vaporisation of a liquid to its gaseous state due to the local absolute pressure falling to the liquid's vapour pressure (Douglas, Gasiorek et al. 1995). Cavitation is present in a wide range of mechanical systems ranging from ship screws to journal bearing. Generally, cavitation is unavoidable and may cause considerable damage and efficiency losses to these systems. This thesis considers hydraulic systems specifically, and uses a modified Greens equation to develop a boundary integral method to simulate the effect that suspended solid bodies have on a single cavitation bubble. Because of the limitations of accurately modelling cavitation bubbles beyond touchdown, results are only presented for cases up to touchdown. The aim of the model is to draw insight into the reasons there is a measurable change in cavitation erosion rate with increasing oil-in-water emulsion percentage. This principle was extended to include the effect that ingested particulates may have on cavitation in hydraulic machinery. Two particular situations are modelled; the first consists of stationary rigid particles in varying proximity to a cavitation bubble near a rigid boundary. The second case is similar; however the suspended particle is allowed to move under the influence of the pressure differential caused by the expanding/contracting cavitation bubble. Numerous characteristics of the domain are considered, including domain pressures and fluid field motion, and individual boundary surface characteristics. The conclusion of the thesis is that solid bodies, either stationary or moving, have little effect on the cavity from an energy perspective. Regardless of size or density, all energy transferred from the cavity to the solid body is returned indicating that there is no net change. As this energy is ultimately responsible for the peak pressure experienced by the domain (and hence responsible for eroding the rigid boundary) as the cavity rebounds, it then serves that a cavity with a solid body will rebound at the same pressure as a cavity without a suspended body present. If this is coupled with the observation that the cavity centroid at touchdown is largely unaffected by the presence of a suspension, then it would appear that the bubble near a solid would rebound at a very similar position as a cavity without a solid. Consequently, the damage potential of a cavity is unaffected by a suspension. However, there is one point of contention as the profile of the re-entrant jet of the cavity is altered by the presence of a suspension. As energy is radiated away from the cavity during penetration, it is possible that the shape of the jet may alter the rate that energy is radiated away during penetration. However, this requires further research to be definitive.
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Holloway, Simon. "Remote sensing measurements of the atmospheric boundary layer : development of a nocturnal boundary layer temperature LiDAR." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/remote-sensing-measurements-of-the-atmospheric-boundary-layer-development-of-a-nocturnal-boundary-layer-temperature-lidar(3de0f22b-8165-4c22-b38e-296062b37940).html.
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A LiDAR instrument to monitor the evolution of the urban boundary layer capping inversion over Manchester has been developed from a previous instrument. This LiDAR uses a frequency-tripled Nd:YAG laser, operating at low pulse energy but high repetition frequency. Rotational Raman scattering of this laser light is parsed into two channels by narrowband interference filters, before detection by photomultiplier tubes operating in photon-counting mode. The receiving telescope was refocused to operate in the boundary layer, and an interference filter was replaced following modelling work. The calibrations of this instrument use locally-launched sondes to determine corrections due to operating in the near-field region of the receiving telescope. The LiDAR receiver was thoroughly calibrated under laboratory conditions to construct a lookup table. Locally-launched sondes were used to correct for mirror shading by instrument components, as well as constrain the overlap function of the BLT. A temperature resolution of better than 0.4K arising from Poisson noise was achieved for data collected for the mean temperature profile measured over the course of a night, with temperature inversions being identifiable down to a height of 500m. A total temperature error of less than 3K was achieved by taking the whole-night mean, which is significantly less than the size of the smallest identified temperature inversion (7.6±2K). The LiDAR instrument data was compared with locally-launched sondes to validate the collected data, agreeing with the sonde measurements to within the uncertainty of the instrument. A WRF model temperature output was compared to both the BLT and sonde data and found to poorly capture the boundary layer temperature profile. The inversion strength was always underestimated by several K, and when the inversion height is below 300m the model underestimates the inversion height by 100-500m.
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Gusev, Ivan. "A mathematical study of the effect of a moving boundary and a thermal boundary layer on droplet heating and evaporation." Thesis, University of Brighton, 2012. https://research.brighton.ac.uk/en/studentTheses/092cc4ff-5890-4f6c-8969-f40b1afa9762.
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Two new solutions to the heat conduction equation, describing transient heating of an evaporating droplet, are suggested. Both solutions take into account the effect of the reduction of the droplet radius due to evaporation, assuming that this radius is a linear function of time. It has been pointed out that the new approach predicts lower droplet surface temperatures and slower evaporation rates compared with the traditional approach. New solutions to the heat conduction equation, describing transient heating of an evaporating droplet, are suggested, assuming that the time evolution of droplet radius Rd(t) is known. The results of calculations are compared with the results obtained using the previously suggested approach, when the droplet radius was assumed to be a linear function of time during individual time steps, for typical Diesel engine-like conditions. Both solutions predict the same results which indicates that both models are likely to be correct. Two new solutions to the equation, describing the diffusion of species during multi-component droplet evaporation, are suggested. The first solution is the explicit analytical solution to this equation while the second one reduces the solution of the differential species diffusion equation to the solution of the Volterra integral equation of the second kind. Both solutions take into account the effect of the reduction of the droplet radius due to evaporation, assuming that this radius is a linear function of time. The analytical solution has been incorporated into a zero dimensional CFD code and applied to the analysis of bi-component (50% ethanol- 50% acetone mixture) droplet evaporation at atmospheric pressure. The transient heat conduction equation, describing heating of a body immersed into gas with inhomogeneous temperature distribution, is solved analytically, assu- ming that, at a certain distance from the body, gas temperature remains constant. The solution is applied to modelling of body heating in conditions close to those observed in Diesel engines. In the long time limit, the distribution of temperature in the body and gas practically does not depend on the initial distribution of gas temperature.
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Stigner, Carl. "A classifying algebra for CFT boundary conditions." Licentiate thesis, Karlstad University, Faculty of Technology and Science, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-4890.
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Conformal field theories (CFT) constitute an interesting class of twodimensionalquantum field theories, with applications in string theoryas well as condensed matter physics. The symmetries of a CFT can beencoded in the mathematical structure of a conformal vertex algebra.The rational CFT’s are distinguished by the property that the categoryof representations of the vertex algebra is a modular tensor category.The solution of a rational CFT can be split off into two separate tasks, apurely complex analytic and a purely algebraic part.
The TFT-construction gives a solution to the second part of the problem.This construction gets its name from one of the crucial ingredients,a three-dimensional topological field theory (TFT). The correlators obtainedby the TFT-construction satisfy all consistency conditions of thetheory. Among them are the factorization constraints, whose implicationsfor boundary conditions are the main topic of this thesis.
The main result reviewed in this thesis is that the factorization constraintsgive rise to a semisimple commutative associative complex algebrawhose irreducible representations are the so-called reflection coefficients.The reflection coefficients capture essential information aboutboundary conditions, such as ground-state degeneracies and Ramond-Ramond charges of string compactifications. We also show that the annuluspartition function can be derived fromthis classifying algebra andits representation theory.
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Loewen, Lydia. "Boundary development in survivors, a group intervention." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0003/MQ32168.pdf.
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Dunlop, Rishma. "Boundary Bay : a novel as educational research." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0015/NQ46339.pdf.
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Shaikh, F. N. "Turbulent spots in a transitional boundary layer." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319596.
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Heredia, N. Fernando. "A new method for boundary value problems." Thesis, Monterey, California. Naval Postgraduate School, 1985. http://hdl.handle.net/10945/21467.
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Savi, L. L. [UNESP]. "A geometric approach to cosmological boundary conditions." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/132136.
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A assimetria temporal observada na física macroscópica se deve à configuração de entropia extremamente baixa do universo primordial. Apesar de a matéria estar muito quente e com uma temperatura uniforme naquele estágio, os graus de liberdade gravitacionais estavam em grande medida suprimidos, fato este que contribui para o baixo valor da entropia e está codificado no alto grau de simetria espacial (caráter aproximadamente Friedman-Lemaître-Robertson-Walker) da superfície de último espalhamento. Analisamos diferentes tentativas de explicar a origem de tal configuração especial. O paradigma inflacionário é testado com respeito a esse problema, e é concluído que a baixa entropia inicial não pode ser explicada dentro dele. Conclusões similares são obtidas com respeito a formulações estatísticas (i.e. antrópicas). Por outro lado, o paradigma conhecido como cosmologia cíclica conforme (CCC) se apresenta como uma nova alternativa que ultrapassa muitas das dificuldades enfrentadas pelos seus rivais, apesar de levantar suas próprias questões em aberto. Introduzimos o modelo juntamente com a estrutura matemática das geometrias de Cartan como um meio possível de atingir um melhor entendimento das condições de contorno cosmológicas. Um elemento que é crucial nessa análise é a modelagem de uma estrutura geométrica de Cartan sobre o espaço de de Sitter SOe(4,1)/SOe(3,1) com um parâmetro de comprimento variável. A introdução de um parâmetro de comprimento na cinemática é favorecida pela observação de uma constante cosmológica positiva e também desejável por motivos oriundos da gravitação quântica, devido à escala natural determinada pelo comprimento de Planck
The observed T-asymmetry of macroscopic physics is traced back to the extremely low entropy configuration of the early universe. Although matter was very hot and with a uniform temperature at that stage, the gravitational degrees of freedom were largely suppressed, which fact contributes to the lowness of the entropy and is encoded in the high level of spatial symmetry (nearly Friedman-Lemître-Robertson-Walker character) of the last scattering surface. I analyze different attempts to explain the origin of such special configuration. The inflation paradigm is probed with respect to this problem, and it is concluded that the initial low entropy cannot be accounted for within it. Similar conclusions are reached with respect to statistical (i.e. anthropic) reasonings. On the other hand, the paradigm known as conformal cyclic cosmology (CCC) presents itself as a new alternative which surpasses many of the difficulties faced by its rivals, although raising its own open questions. I introduce the model together with the mathematical structure of Cartan geometries as a possible means of achieving a better understanding of cosmological boundary conditions. One element which is crucial in this analysis is the modeling of the Cartan geometric structure over a de Sitter space SOe(4,1)/SOe(3,1) with varying length parameter. The introduction of a length parameter in the kinematics is favored by the observation of a positive cosmological constant and also desirable for quantum gravity reasons, due to the natural scale set by Planck's constant
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Savi, L. L. (Lucas Lolli). "A geometric approach to cosmological boundary conditions /." São Paulo, 2015. http://hdl.handle.net/11449/132136.
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Orientador: José Geraldo PereiraBanca: Bruto Max Pimentel Escobar
Banca: Roldão da Rocha Junior
Banca: Davi Cabral Rodrigues
Banca: José abdalla Helayel-Neto
Resumo: A assimetria temporal observada na física macroscópica se deve à configuração de entropia extremamente baixa do universo primordial. Apesar de a matéria estar muito quente e com uma temperatura uniforme naquele estágio, os graus de liberdade gravitacionais estavam em grande medida suprimidos, fato este que contribui para o baixo valor da entropia e está codificado no alto grau de simetria espacial (caráter aproximadamente Friedman-Lemaître-Robertson-Walker) da superfície de último espalhamento. Analisamos diferentes tentativas de explicar a origem de tal configuração especial. O paradigma inflacionário é testado com respeito a esse problema, e é concluído que a baixa entropia inicial não pode ser explicada dentro dele. Conclusões similares são obtidas com respeito a formulações estatísticas (i.e. antrópicas). Por outro lado, o paradigma conhecido como cosmologia cíclica conforme (CCC) se apresenta como uma nova alternativa que ultrapassa muitas das dificuldades enfrentadas pelos seus rivais, apesar de levantar suas próprias questões em aberto. Introduzimos o modelo juntamente com a estrutura matemática das geometrias de Cartan como um meio possível de atingir um melhor entendimento das condições de contorno cosmológicas. Um elemento que é crucial nessa análise é a modelagem de uma estrutura geométrica de Cartan sobre o espaço de de Sitter SOe(4,1)/SOe(3,1) com um parâmetro de comprimento variável. A introdução de um parâmetro de comprimento na cinemática é favorecida pela observação de uma constante cosmológica positiva e também desejável por motivos oriundos da gravitação quântica, devido à escala natural determinada pelo comprimento de Planck
Abstract:The observed T-asymmetry of macroscopic physics is traced back to the extremely low entropy configuration of the early universe. Although matter was very hot and with a uniform temperature at that stage, the gravitational degrees of freedom were largely suppressed, which fact contributes to the lowness of the entropy and is encoded in the high level of spatial symmetry (nearly Friedman-Lemître-Robertson-Walker character) of the last scattering surface. I analyze different attempts to explain the origin of such special configuration. The inflation paradigm is probed with respect to this problem, and it is concluded that the initial low entropy cannot be accounted for within it. Similar conclusions are reached with respect to statistical (i.e. anthropic) reasonings. On the other hand, the paradigm known as conformal cyclic cosmology (CCC) presents itself as a new alternative which surpasses many of the difficulties faced by its rivals, although raising its own open questions. I introduce the model together with the mathematical structure of Cartan geometries as a possible means of achieving a better understanding of cosmological boundary conditions. One element which is crucial in this analysis is the modeling of the Cartan geometric structure over a de Sitter space SOe(4,1)/SOe(3,1) with varying length parameter. The introduction of a length parameter in the kinematics is favored by the observation of a positive cosmological constant and also desirable for quantum gravity reasons, due to the natural scale set by Planck's constant
Doutor
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Bhide, Kalyani R. "Shock Boundary Layer Interactions - A Multiphysics Approach." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1543994392025663.
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Brereton, Ashley. "Phytoplankton aggregations in a turbulent boundary layer." Thesis, University of Liverpool, 2013. http://livrepository.liverpool.ac.uk/15833/.
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Phytoplankton aggregations come in a wide range of space and time scales and, as such, simulating such behavior is computationally restrictive. I present a Large-eddy simulation of the upper mixed layer, resolving scales of o(1m). I then show how aggregations are promoted by nutrient upwellings (something which macroscale models struggle to emulate), facilitated primarily by Langmuir circulations. I then demonstrate how certain levels of turbulent mixing encourage planktonic thin layering, a phenomenon which is widely observed.
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Williams, Simon. "Three-dimensional separation of a hypersonic boundary layer." Thesis, Imperial College London, 2005. http://hdl.handle.net/10044/1/11450.
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Stamicar, Robert. "A free boundary problem modelling zoning in rocks." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0004/NQ42881.pdf.
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Stamic̆ar, Robert Nikola. "A free boundary problem modelling zoning in rocks /." *McMaster only, 1998.
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Ghazawneh, Ahmad. "Towards a Boundary Resources Theory of Software Platforms." Doctoral thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Informatik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-19820.
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The last few years have witnessed a significant increase in the frequency and magnitude of involving third-party application developers in software platforms. While this involvement offers great opportunities in building and sustaining platform innovation, it also exposes platform owners to significant challenges. Typically, platform owners facilitate the involvement of third-party developers by providing resources, referred to in this thesis as boundary resources, that give access to the platform, shift design capability, and facilitate the use of the platform’s core technologies. At the same time, these resources have the potential to be used to maintain platform control. This involves seemingly conflicting goals that creates a challenge for platform owners in finding the right balance. The main objective of this thesis is to investigate and understand the role of boundary resources in platform owners’ efforts to stimulate third-party development. To this end, this thesis proposes a theoretical model of boundary resources. This model centres on various drivers behind boundary resources design and use, and how these drivers interact in third-party development. The thesis also presents a comprehensive view of governance and strategizing practices used by platform owners through boundary resources. This thesis comprises a cover and a collection of five published research papers. The thesis applies a qualitative research method and employs multiple case studies. Boundary resources, innovation networks and platform governance perspectives have been synthesized to build a theoretical basis to analyze the empirical findings. This thesis complements and extends the literature on software platforms, and the insights derived from the thesis enhance previous research on third-party development. In addition, it provides a focused theoretical account of the interfaces between platform owners and third-party developers that contributes to the body of knowledge developed around using tools for innovation.
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McBean, David P. O. "Board interconnect testing in a boundary scan environment." Thesis, University of Oxford, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333253.
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Metcalfe, S. J. "A blow-up mechanism in boundary layer transition." Thesis, Keele University, 2013. http://eprints.keele.ac.uk/193/.
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McFiggans, Gordon. "A modelling study of marine boundary layer chemistry." Thesis, University of East Anglia, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323352.
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Shola, Peter Bamidele. "Numerical solution of a free-boundary viscous flow." Thesis, University of Essex, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.256393.
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Williams, Jonathan Jowett. "Aeolian entrainment thresholds in a developing boundary layer." Thesis, Queen Mary, University of London, 1986. http://qmro.qmul.ac.uk/xmlui/handle/123456789/28966.
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The aeolian threshold condition is identified as defining the critical state between a static sediment bed and active aeolian transport. Disparities in reported mean threshold shear velocities (U*T) are attributed to variation in: (a) flow regimes; (b) entrainment criteria; (c) particle characteristics and exposures; and (d) techniques for measurement of 1*T The relative significance of these factors is assessed for strips and beds of ballotini, aeolian sand, salt crystals and sugar crystals using the controlled, reproducible flow conditions of the developing boundary layer over a flat plate. Such a plate was covered with a non-erosive layer of grains to simulate a flat sediment bed and was positioned in a wind tunnel. values were calculated using the momentum integral method. In a separate study, threshold conditions on impervious and permeable beds were compared directly. Analysis of entrainment from strips and beds on the plate shows that the threshold condition is principally determined by a critical degree of overlap between the probability distributions of local shear velocity, P ( U ), and of grain threshold shear velocity, P(U*T). Characteristic P(U*T) distributions for test materials were determined and two objective definitions of U*T were devised. Experimental *T values agree well with published data and are used to resolve the data scatter associated with both 'restricted' and 'universal' threshold curves. Rates of aeolian entrainment over a range of values are found to be an inverse exponential function of time and wind speed. Different erosion rates were found to result from skewness of P(U) and degree of overlap between P(U) and P(U*T). Fluid sweeps in the turbulent bursting cycle are considered to be the primary entrainment mechanism. Medium/high-speed cine film gave insight into initiation processes. Grain oscillation due to vortex shedding and initial motion characterized by a progressive rolling and bouncing were observed. Bed permeability was not found to affect aeolian threshold values.
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Olsson, Jörgen. "Localized disturbances in a flat plate boundary layer." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/47351.
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Plas, Angélique (Angélique Pascale). "Performance of a boundary layer ingesting propulsion system." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35568.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2006.Includes bibliographical references (p. 111-114).
This thesis presents an assessment of the aerodynamic performance of an aircraft propulsion system, with embedded engines, in the presence of aircraft fuselage boundary layer ingestion (BLI). The emphasis is on defining the role that the turbomachinery (i.e., the fan, in the ultra high bypass engines considered) plays in establishing the flow benefit due to BLI. A three-dimensional body force approach to fan response to inlet distortion has been utilized to analyze the flow in the engine ducts. In addition to providing quantitative information as to the fuel burn benefit from BLI, the body force approach is also compared with two simpler analyses, one based on the parallel compressor concept and one based on integral boundary layer methodology. It is shown that the distortion transfer across the fan, basically attenuation of the stagnation pressure non-uniformity downstream of the fan compared to that upstream of the fan plays a major role in determining the impact of boundary layer ingestion on fuel burn. This, in turn, puts requirements on the fidelity with which one needs to assess the distortion transfer, and thus the type of models to be used in such assessment.
(cont.) In terms of qualitative information, the three models are found to give broadly similar trends for distortion attenuation and for fuel burn benefit. In terms of quantitative results, the body force analysis shows that for a fan diameter and flight condition representative of that employed in the Cambridge-MIT Institute "Silent Aircraft" boundary layer ingestion can provide decreases in fuel burn of up to 3.8 percent.
by Angélique Plas.
S.M.
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Khalid, A. H. "Free boundary problems in a Hele-Shaw cell." Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1463159/.
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The motion of a free boundary separating two immiscible fluids in an unbounded Hele-Shaw cell is considered. In the one-phase problem, a viscous fluid is separated from an inviscid fluid by a simple closed boundary. Preliminaries for a complex variable technique are presented by which the one-phase problem can be solved explicitly via conformal mappings. The Schwarz function of the boundary plays a major role giving rise to the so called Schwarz function equation which governs the evolution of exact solutions. The Schwarz function approach is used to study the stability of a translating elliptical bubble due to a uniform background flow, and the stability of a blob (or bubble) subject to an external electric field. The one-phase problem of a translating free boundary and of a free boundary subject to an external field are studied numerically. A boundary integral method is formulated in the complex plane by considering the Cauchy integral formula and the complex velocity of a fluid particle on the free boundary. In the case of a free boundary subject to an external electric field due to a point charge, it is demonstrated that a stable steady state is achieved for appropriate charge strength. The method is also employed to study breakup of a single translating bubble in which the Schwarz function singularities (shown to be stationary) of the initial boundary play an important role. The two-phase problem is also considered, where the free boundary now separates two viscous fluids, and the construction of exact solutions is studied. The one-phase numerical model is enhanced, where a boundary integral method is formulated to accommodate the variable pressure in both viscous phases. Some numerical experiments are presented with a comparison to analytical results, in particular for the case where the free boundary is driven by a uniform background flow.
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Al-Ghamdi, Ahmed Abdullah Saud. "The Saudi-Yemeni boundary : towards a peaceful resolution." Thesis, Durham University, 1996. http://etheses.dur.ac.uk/1650/.
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Wang, Hongwei. "Boundary Layer Characteristics on a Tiltrotor Blade Model." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/33630.
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Boundary layer characteristics at the trailing edge of a tiltrotor blade model were measured using a flattened pitot probe and a single hot wire. The blade was mounted in Virginia Tech Stability Wind tunnel stationary on a turntable on the wind tunnelâ s upper wall with the tip pointing down. The measurement point was located at 1 mm behind the trailing edge to make it possible to measure the flow near the blade surface and measure the boundary layer on both sides of the trailing edge in a same run. Mean velocity profiles were measured for a variety of Reynolds numbers and angles of attack. Turbulence intensity and spectral measurements were performed using a single hot wire at the highest Reynolds number. Conclusion was reached that both of the flattened pitot probe and single hot wire are good for boundary layer thickness measurements. Displacement thickness, which is important in trailing edge noise prediction, was calculated from the profile data and fit using an algebra expression against the tip angle of attack. Once the relationship between tip angle of attack and local effective angle of attack is obtained by lifting line theory, the results can be used in the trailing edge noise prediction code.Master of Science
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Ahlin, Karin. "Approaching the intangible benefits of a boundary object." Licentiate thesis, Mittuniversitetet, Avdelningen för data- och systemvetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-21576.
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Today´s information society is constantly increasing the quantity of digital information that organisations have access to and depend on. Despite this dependency, few descriptions exist of the benefits which this digital information can provide the organisation with. Examples of what the organisation can use the information for include business intelligence or in a business process. The absence of such benefit descriptions results in missed opportunities in organisational management and a failure to cultivate the artefact. In terms of a practical operational work role, this means that the artefact just exists and that there are no decisions, communication and discussions connected to it. Earlier research about benefits in the Information Systems field is focused on describing the process of finding benefit factors from different IT investments and how these investments can be measured financially. The result of this was that it was only the measurable benefits that were taken into consideration. Later benefit management research has shown interest in the intangible benefit factors as well and added this as an activity in the evaluation process. Today´s view is that the benefit consists both of tangible and intangible benefit factors. This thesis emphasises benefit factors found by means of qualitative research in organisations producing Technical Information (TI). TI isinformation connected to goods and services and is a part of a product. The intangible benefit factors found which are connected to TI are semantic interoperability and knowledge. Semantic interoperability is beneficial both for the organisation and the individuals – in the first case exemplified by a uniform working process and in the second as efficiency in the internal communication. Knowledge also provides benefit both to the organisation and the individuals – the organisation can operate without depending on certain individuals and information gives the individuals mobility in their profession.The next part in the thesis discusses information management´simpact on benefit factors. In the case of an autocratic approach, it is the organisation that benefits most, whereas a decentralised management style provides the individual co-workers with a greater number of benefit factors. This proves that information management is an important and decisive ingredient, and that it affects benefit factors.One step in the direction of converting the intangible benefit factors into tangible ones is to visualise them. In this work the theoreticallens provided by a boundary object has been used. This lens adds a qualitative view on cross-boundary information and has efficiency approaches. These approaches are the syntactical, semantic andpragmatic. Via interpretations from the thesis´s two empirical cases, those approaches are "measured" by interpretations and visualised by the three leaves of a clover. This gives the opportunity to describewhat information efficiency, in this case connected to a positiveexpectation, can contribute to the organisation or the individuals. By this procedure, different cases or time aspects can be compared,thereby providing a basis for decision-making, communication and discussion. Future research in this area can be made in different directions – one is to investigate whether the intangible benefit factors can be turned into measurable ones. In this way, the internal organisation can be provided with better knowledge of the digital information's impact. Another research direction is to investigate how the passage of time affects the benefit factors that digital information gives the organisation.
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Al-Salman, Adam. "Nonlinear modal interactions in a compressible boundary layer." Thesis, Imperial College London, 2003. http://hdl.handle.net/10044/1/61537.
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It is well known that boundary layers in the supersonic regime can support multiple instability modes, including the well-documented first and second modes. The main aim of this thesis is to investigate nonlinear modal interactions. Since an instability mode attains its maximum magnitude in its critical layer (i.e. the region surrounding the position where the basic flow velocity is equal to the phase velocity), particularly effective interactions can take place among modes which share the same critical layer. As a first step, we solved the compressible Rayleigh equation, using parameters representing practical supersonic flows. Our calculations show that the resonant triad and phase-locked interactions can occur among purely first modes, or a certain combination of first and second modes. A new type of interaction between two or more modes which are frequency-locked, was identified. Each of these interactions has been studied in the so-called nonlinear nonequilibrium viscous critical-layer regime. For the resonant triad interaction, we derived a system of integro-partial-differential equations, which govern the spatial-temporal modulation of a triad, consisting of two oblique and one planar wavetrains. In the first stage, the amplitude of the planar wavetrain is governed by a linear equation. The oblique wavetrain amplitudes are governed by a set of coupled nonlinear equations, due to the quadratic interaction between the oblique and the planar wavetrains, which takes place in their common critical layers. These equations are solved for the two cases of interest where each wavetrain has a discrete spectrum or a narrow band continuous spectrum. Our results are able to capture experimental observations qualitatively. The disturbance enters the second stage once the planar wave has grown to such an extent that its self nonlinearity becomes significant. We find that the viscosity law can affect the form of the nonlinear term in the planar wave amplitude equation. As a result of this, the solution to this equation saturates. The previously super-exponential growth of the oblique wave is reduced to exponential growth. Similarly for the phase-locked interaction, we derived a system of integro-partial-differential equations, which govern the spatial-temporal modulation of a pair of wavetrains. Again in the first stage of the development, the planar mode is governed by a linear equation, but it interacts with the obhque mode to generate a large difference mode, which in turn interacts with the planar mode, to contribute a cubic nonlinear term to the amplitude equation of the oblique mode. These equations are solved for the case of interest where the wavetrains have a narrow band continuous spectra. The evolution of these waves in the second stage where the planar wave becomes nonlinear is also investigated. Next we studied the interaction between two oblique modes which are frequency-locked, in the sense that they all have the same streamwise wave number and frequency. This is a unique feature of supersonic flows, and may be relevant for the K-type of transition. We also investigate this type of interaction between two pairs of oblique modes. Finally we considered the streamwise-spanwise modulation of a nearly planar acoustic mode in a hypersonic boundary layer. We derived an evolution system consisting of an amplitude equation coupled to the two strongly nonlinear equations for the vorticity and temperature in the critical layer.
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Lucas, Regina Marie. "Ralph and Lily: Victims in a Boundary World." W&M ScholarWorks, 1998. https://scholarworks.wm.edu/etd/1539626174.
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Lee, Yoon-Mee. "Hopf Bifurcation in a Parabolic Free Boundary Problem." DigitalCommons@USU, 1992. https://digitalcommons.usu.edu/etd/7138.
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We deal with a free boundary problem for a nonlinear parabolic equation, which includes a parameter in the free boundary condition. This type of system has been used in models of ecological systems, in chemical reactor theory and other kinds of propagation phenomena involving reactions and diffusion.
The main purpose of this dissertation is to show the global existence, uniqueness of solutions and that a Hopf bifurcation occurs at a critical value of the parameter r. The existence and uniqueness of the solution for this problem are shown by finding an equivalent regular free boundary problem to which existence results can be applied. We then show that as the bifurcation parameter r decreases and passes through a critical value rc, the stationary solution loses stability and a stable periodic solution appears. Several figures have been included, which illustrate this transistion. The pascal source program used in the numerical simulation is included in an appendix.
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Johansson, Tomas. "Reconstruction of a stationary flow from boundary data." Licentiate thesis, Linköpings universitet, Kommunikations- och transportsystem, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-140141.
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We study a Cauchy problem arising in uid mechanics, involving the socalled stationary generalized Stokes system, where one should recover the ow from boundary measurements. The problem is ill-posed in the sense that the solution does not depend continuously on data. Two iterative procedures for solving this problem are proposed and investigated. These methods are regularizing and in each iteration one solves a series of well-posed problems obtained by changing the boundary conditions. The advantage with this approach, is that these methods place few restrictions on the domain and on the coe_cients of the problem. Also the structure of the equation is preserved. Well-posedness of the problems used in these procedures is demonstrated, i.e., that the problems have a unique solution that depends continuously on data. Since we have numerical applications in mind, we demonstrate well-posedness for the case when boundary data is square integrable. We give convergence proofs for both of these methods.
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Smith, Malcolm Gordon. "Sound radiation from a vibrating surface under a boundary layer." Thesis, University of Southampton, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398608.
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Breuer, Kenneth Samuel. "The development of a localized disturbance in a boundary layer." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/34991.
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Modh, Sandra Violeta. "Lamaholot of East Flores : a study of a boundary community." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:b7693f46-3a18-4b1a-ba96-0f17e91f0282.
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Lamaholot is a population found on Flores and in the Solor Archipelago of Eastern Indonesia. The population is village-based and divided into patrilineal descent groups. Marriage is coupled with bridewealth and follows a pattern of asymmetric marriage alliance between descent groups. This thesis shows that a small group of Lamaholot in the administrative regency of East Flores shares certain traditions with a neighbouring population called Ata Tana ‘Ai. Ata Tana ‘Ai are a sub-group of the Sikka population in the administrative regency of Sikka. Descent group among Ata Tana ‘Ai are matrilineal and households were traditionally based in scattered gardens. Marriage is not coupled with bridewealth and instances of asymmetric marriage alliance between descent groups are here a consequence rather than a cause of marriage. The current fieldsite seems to have been part of the ceremonial system of Ata Tana ‘Ai and also to have shared a tradition of dispersed settlement in the gardens. The descent groups might initially have been matrilineal, but in the recent past there was also a habit of dividing children between the parental descent groups. Recent traditions of dividing children can be found throughout central-east Flores, but seemingly not to same extent as at the fieldsite. The payment of elephant’s tusks was a central feature in the acquisition of group members at the fieldsite and could be paid by both men and women. These payments were not necessarily tied to marriage and did not serve as bridewealth. In the last century outer social factors, such as the Catholic mission and the creation of the Dutch colonial state, have resulted in that many of the traditional practices at the fieldsite have been replaced with traditions from Lamaholot elsewhere. The residence pattern is now village-based, but gardens retain a central social and ritual position. The role of the elephant’s tusks has taken different expressions throughout this period of social change, and alongside the changing role of tusks, the traditional social and material authority of women at the fieldsite has declined, whereas that of men has increased. This thesis examines the current and the traditional practices in and around the fieldsite, and focuses on local definitions of descent group, kinship, and inheritance, looking at both biological and social perspectives.
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Gertzell, Christopher. "Change agents as boundary spanners : -A case study of how change agents acts as boundary spanners within a major business transformation." Thesis, Uppsala universitet, Företagsekonomiska institutionen, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-264297.
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Sandanayake, Don Suneth Sameera. "Stope boundary optimisation in underground mining based on a heuristic approachStope boundary optimisation in underground mining based on a heuristic approach." Thesis, Curtin University, 2014. http://hdl.handle.net/20.500.11937/1725.
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Stope optimisation is pivotal to maximisation of NPV of an underground mining project. However, none of the algorithms developed for stope optimisation guarantees optimal stope layout due to the computational complexity of the problem. The research proposes an innovative heuristic based algorithm to generate optimal stope layout for a given resource model. The developed algorithm is implemented on a real-case block model representing a Copper deposit and compared with two existing algorithms in case studies.
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Grudsky, Serguey, and Nikolai Tarkhanov. "Conformal reduction of boundary problems for harmonic functions in a plane domain with strong singularities on the boundary." Universität Potsdam, 2012. http://opus.kobv.de/ubp/volltexte/2012/5774/.
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We consider the Dirichlet, Neumann and Zaremba problems for harmonic functions in a bounded plane domain with nonsmooth boundary. The boundary curve belongs to one of the following three classes: sectorial curves, logarithmic spirals and spirals of power type. To study the problem we apply a familiar method of Vekua-Muskhelishvili which consists in using a conformal mapping of the unit disk onto the domain to pull back the problem to a boundary problem for harmonic functions in the disk. This latter is reduced in turn to a Toeplitz operator equation on the unit circle with symbol bearing discontinuities of second kind. We develop a constructive invertibility theory for Toeplitz operators and thus derive solvability conditions as well as explicit formulas for solutions.
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Kral, Linda Dee. "Numerical investigation of transition control of a flat plate boundary layer." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184621.
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A numerical model has been developed for investigating boundary layer transition control for a three-dimensional flat plate boundary layer. Control of a periodically forced boundary layer in an incompressible fluid is studied using surface heating techniques. The spatially evolving boundary layer is simulated. The Navier-Stokes and energy equations are integrated using a fully implicit finite difference/spectral method. The Navier-Stokes equations are in vorticity-velocity form and are coupled with the energy equation through the viscosity dependence on temperature. Both passive and active methods of control by surface heating are investigated. In passive methods of control, wall heating is employed to alter the stability characteristics of the mean flow. Both uniform and nonuniform surface temperature distributions are studied. In the active control investigations, temperature perturbations are introduced locally along finite heater strips to directly attenuate the instability waves in the flow. A feedback control loop is employed in which a downstream sensor is used to monitor wall shear stress fluctuations. Passive control of small amplitude two-dimensional Tollmien-Schlichting waves and three-dimensional oblique waves are numerically simulated with both uniform and nonuniform passive heating applied. Strong reductions in both amplitude levels and amplification rates are achieved. Active control of small amplitude two-dimensional and three-dimensional disturbances is also numerically simulated. With proper phase control, in phase reinforcement and out of phase attenuation is demonstrated. A receptivity study is performed to study how localized temperature perturbations are generated into Tollmien-Schlichting waves. It is shown that narrow heater strips are more receptive in that they maximize the amplitude level of the disturbances in the flow. It is also found that the local temperature fluctuations cause mainly a strong normal gradient in spanwise vorticity. Control of the early stages of the nonlinear breakdown process is also investigated. Uniform passive control is applied to both the fundamental and sub-harmonic routes to turbulence. A strong reduction in amplitude levels and growth rates results. In particular, the three-dimensional growth rates are significantly reduced below the uncontrolled levels. Active control of the fundamental breakdown process is also numerically simulated. Control is achieved using either a two-dimensional or three-dimensional control input.
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Hernandez, Medina Santiago. "Turbulent interface phenomena in a temporally developing boundary layer." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14721/.
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The purpose of the current study was to examine the characteristics and behavior of the turbulent/non-turbulent interface on a temporally developing boundary layer.
Flow topology, turbulent statistics, enstrophy budgets and spectral statistics were computed with the purpose of acquiring meaningful results.
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Eibner, Tino, and Jens Markus Melenk. "A local error analysis of the boundary concentrated FEM." Universitätsbibliothek Chemnitz, 2006. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200601440.
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The boundary concentrated finite element method is
a variant of the hp-version of the FEM that is
particularly suited for the numerical treatment of
elliptic boundary value problems with smooth
coefficients and boundary conditions with low
regularity or non-smooth geometries. In this paper
we consider the case of the discretization of a
Dirichlet problem with exact solution
$u \in H^{1+\delta}(\Omega)$ and investigate the
local error in various norms. We show that for
a $\beta > 0$ these norms behave as
$O(N^{−\delta−\beta})$, where $N$ denotes the
dimension of the underlying finite element space.
Furthermore, we present a new Gauss-Lobatto based
interpolation operator that is adapted to the
case non-uniform polynomial degree distributions.