To see the other types of publications on this topic, follow the link: Bubble Theory.
Dissertations / Theses on the topic 'Bubble Theory'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Bubble Theory.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Mauá, Sara Malvar. "Bubble dynamics in magnetic fluids : theory and applications." reponame:Repositório Institucional da UnB, 2015. http://repositorio.unb.br/handle/10482/19461.
Full textAbstract:
Dissertação (mestrado)—Universidade de Brasília, Faculdade de Tecnologia, Departamento de Engenharia Mecânica, 2015.Submitted by Fernanda Percia França (fernandafranca@bce.unb.br) on 2015-12-17T17:13:08Z No. of bitstreams: 1 2015_SaraMalvarMauá.pdf: 111260219 bytes, checksum: 51c18f67aa6cbe9639aa0abfb22e32b0 (MD5)
Approved for entry into archive by Raquel Viana(raquelviana@bce.unb.br) on 2016-02-05T18:43:44Z (GMT) No. of bitstreams: 1 2015_SaraMalvarMauá.pdf: 111260219 bytes, checksum: 51c18f67aa6cbe9639aa0abfb22e32b0 (MD5)
Made available in DSpace on 2016-02-05T18:43:44Z (GMT). No. of bitstreams: 1 2015_SaraMalvarMauá.pdf: 111260219 bytes, checksum: 51c18f67aa6cbe9639aa0abfb22e32b0 (MD5)
O presente trabalho tem por objetivo principal investigar o comportamento não-linear de uma bolha imersa em um fluido magnético, sujeita a um campo de pressão acústico e um campo magnético. Uma nova versão da equação de Rayleigh-Plesset e proposta com o tensor magnético. Esta equação para dinâmica de bolhas e resolvida computacionalmente pelo método Runge-Kutta de quinta ordem com passo de tempo adaptativo, visando diminuir o custo computacional. O código e validado por meio de uma teoria assintótica em função da amplitude de excitação e do numero de Reynolds Magnético. A influência de parâmetros adimensionais e investigada, como o numero de Reynolds e Weber e dos parâmetros magnéticos, como Reynolds Magnético e Susceptibilidade Magnética. A excitação magnética aplicada foi variada contando com campos oscilatórios e constantes. Uma solução assintótica para o raio mínimo de colapso e apresentada. Isto permite uma analise utilizando tanto as teorias de estabilidade linear hidrodinâmica quanto as teorias não-lineares - como as redes neurais e os expoentes de Lyapunov. Uma serie de analises como diagrama de bifurcação dos padrões vibracionais e diagramas de colapso são construídos. Neste contexto, um novo método baseado nas ferramentas de diagrama de fase e DFT e proposto para analisar o comportamento da bolha oscilando em diferentes números de Reynolds Magnético e Suscetibilidade Magnética. Os novos padrões vibracionais apresentados devido ao acoplamento das escalas de tempo do problema são estudados e que leva a identificação de padrões caóticos. Neste sentido, a magnetização do ferrofluido e analizada tanto do ponto de vista das interações partícula-partícula, utilizando-se tanto das ferramentas já apresentadas quanto da equação fenomenológica da magnetização. Essa ultima permite a comparação deste modelo com o modelo superparamagnético proposto para a modelagem matemática. Visando verificar os conceitos utilizados e as hipóteses restritivas de movimento radial e não deformação uma bancada experimental e desenvolvida. Nesta bancada, estuda-se uma bolha ascendente em diversos fluidos magnéticos que foram sintetizados para este fim. Estes fluidos tem suas características analizados por meio de um reometro de discos rotativos e um tensiometro. Por fim, adiciona-se um campo magnético estacionário por meio de um ima de neodímio e observa-se como a bolha responde. __________________________________________________________________________________________________ ABSTRACT
The main purpouse of the present work is to investigate the nonlinear behaviour of a bubble immersed in a magnetic fluid, subjected to an acoustic pressure forcing and a magnetic field. A new version of the Rayleigh-Plesset equation is proposed with the magnetic tensor. That equation is numerically solved using a fith order Runge-Kutta scheme with and adaptive time step, in order to lower the computacional cost. That code is validated with an asymptotic solution in terms of Magnetic Reynolds number and the pressure forcing amplitude. The influence of the main Newtonian dimentionless physical parameters, such as the Reynolds and Weber numbers and the non-Newtonian parameters, as Magnetic Reynolds and Magnetic Susceptibility are investigated. The applied magnetic excitation was varied between stationary and oscillatory fields. An asymptotic theory for the minimum radius before collapse is presented. This permits an analysis using both hydrodynamic linear stability theory and nonlinear theories, such as neural networks and Lyapunov exponents. A serie of analyzes using vibrational pattern bifurcation diagrams and collapse diagrams are built. In this context, a new method based in the phase plot and DFT is proposed in order to analyze the bubble behavior when oscillating. The identified vibrational patterns are studied in order to generate chaotic patterns due to time scales coupling. In this sense, the magnetization of the ferrofluid is analyzed from the particle-particle interactions point of view, using the tools already presented and the phenomenological equation of magnetization. This last allows the comparison of this model with the superparamagnetic model proposed for the mathematical modeling. In order to verify the concepts used, the restrictive assumption of radial movement and lack of deformation an experimental bench is developed. In this bench, a rising bubble immersed in synthesized magnetic fluid is observed. These fluids have their characteristics (such as viscosity and surface tension) analyzed using a rotating disc rheometer and a tensiometer. Finally, a stationary magnetic field is applied using a neodymium magnet and the bubble behavior is observed.
2
Llewellin, Edward William. "The rheology of bubble bearing magmas : theory and experiments." Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.251071.
Full text
3
Hmaida, Mufida Mohamed A. "Representation theory of algebras related to the bubble algebra." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/15987/.
Full textAbstract:
In this thesis we study several algebras which are related to the bubble algebra, including the bubble algebra itself. We introduce a new class of multi-parameter algebras, called the multi-colour partition algebra $ P_{n,m} ( \breve{\delta} )$, which is a generalization of both the partition algebra and the bubble algebra. We also define the bubble algebra and the multi-colour symmetric groupoid algebra as sub-algebras of the algebra $ P_{n,m} ( \breve{\delta} ) $. We investigate the representation theory of the multi-colour symmetric groupoid algebra $ \F S_{n,m} $. We show that $ \F S_{n,m} $ is a cellular algebra and it is isomorphic to the generalized symmetric group algebra $ \F \mathbb{Z}_m \wr S_n $ when $ m $ is invertible and $ \F $ is an algebraically closed field. We then prove that the algebra $ P_{n,m} ( \breve{\delta} ) $ is also a cellular algebra and define its cell modules. We are therefore able to classify all the irreducible modules of the algebra $ P_{n,m} ( \breve{\delta} ) $. We also study the semi-simplicity of the algebra $ P_{n,m} ( \breve{\delta} ) $ and the restriction rules of the cell modules to lower rank $ n $ over the complex field. The main objective of this thesis is to solve some open problems in the representation theory of the bubble algebra $ T_{n,m} ( \breve{\delta} ) $. The algebra $ T_{n,m} ( \breve{\delta} ) $ is known to be cellular. We use many results on the representation theory of the Temperley-Lieb algebra to compute bases of the radicals of cell modules of the algebra $ T_{n,m} ( \breve{\delta} ) $ over an arbitrary field. We then restrict our attention to study representations of $ T_{n,m} ( \breve{\delta} ) $ over the complex field, and we determine the entire Loewy structure of cell modules of the algebra $ T_{n,m} ( \breve{\delta} ) $. In particular, the main theorem is Theorem 5.41.
4
Burley, Adam Craig. "Toward a Fundamental Understanding of Bubble Nucleation in Polymer Foaming." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1338220471.
Full text
5
Kauper, Benjamin, and Karl-Kuno Kunze. "Modellierung von Aktienkursen im Lichte der Komplexitätsforschung." Universität Potsdam, 2011. http://opus.kobv.de/ubp/volltexte/2011/5228/.
Full textAbstract:
This paper offers empirical evidence on the power of Sornette et al's [2001] model of bubbles and crashes regarding the German stock market between 1960 and 2009. We identify relevant time periods and describe them with the function given by Sornette et al's model. Our results show some evidence in predicting crashes with the understanding of logarithmic periodic structures that are hidden in the stock price trajectories. It was shown that for the DAX most of the relevant parameters determining the shape of the logarithmic periodic structures are lying in the expected interval researched by Sornette et al. Further more the paper implicitly shows that the point of time of former crashes can be predicted with the presented formula. We conclude that the concept of financial time series conceived as purely random objects should be generalised as to admit complexity.
6
Kundiger, Kyle. "Optimal investment strategies using multi-property commercial real estate analysis of pre/post housing bubble." Honors in the Major Thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/575.
Full textAbstract:
This paper analyzes theperformance of five commercial real estate property types (office, retail, industrial, apartment, and hotel) between 2000 and 2012 to determine the U.S. housing crisis'simpact on Real Estate investing. Under the concept of Modern Portfolio Theory, the data was analyzed using investment analysis programs to determine correlation, risk/return characteristics, and trade-offs (Sharpe ratio) as well as the optimal allocation among the individual property types. In light of the results, each property type plays a different role in investment strategies in various economic cycles. Some assets are attractive solely based onpotential return, or risk for return tradeoffs; however, through diversification, other property types play valuable roles in hedging risk on investors' target returns.B.A. and B.S.
Bachelors
Business Administration
Finance
7
Ghaderi, Hazhar. "The Phase-Integral Method, The Bohr-Sommerfeld Condition and The Restricted Soap Bubble : with a proposition concerning the associated Legendre equation." Thesis, Uppsala universitet, Institutionen för fysik och astronomi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-169572.
Full textAbstract:
After giving a brief background on the subject we introduce in section two the Phase-Integral Method of Fröman & Fröman in terms of the platform function of Yngve and Thidé. In section three we derive a different form of the radial Bohr-Sommerfeld condition in terms of the apsidal angle of the corresponding classical motion. Using the derived expression, we then show how easily one can calculate the exact energy eigenvalues of the hydrogen atom and the isotropic three-dimensional harmonic oscillator, we also derive an expression for higher order quantization condition. In section four we derive an expression for the angular frequencies of a restricted (0≤φ≤β) soap bubble and also give a proposition concerning the parameters l and m of the associated Legendre differential equation.Vi använder Fröman & Frömans Fas-Integral Metod tillsammans med Yngve & Thidés plattformfunktion för att härleda kvantiseringsvilkoret för högre ordningar. I sektion tre skriver vi Bohr-Sommerfelds kvantiseringsvillkor på ett annorlunda sätt med hjälp av den så kallade apsidvinkeln (definierad i samma sektion) för motsvarande klassiska rörelse, vi visar också hur mycket detta underlättar beräkningar av energiegenvärden för väteatomen och den isotropa tredimensionella harmoniska oscillatorn. I sektion fyra tittar vi på en såpbubbla begränsad till området 0≤φ≤β för vilket vi härleder ett uttryck för dess (vinkel)egenfrekvenser. Här ger vi också en proposition angående parametrarna l och m tillhörande den associerade Legendreekvationen.
8
Geiger, Karen Audrey. "Cross-Race Relationships as Sites of Transformation: Navigating the Protective Shell and the Insular Bubble." Antioch University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=antioch1289853182.
Full text
9
Patraucean, Viorica. "Detection and identification of elliptical structure arrangements in images : theory and algorithms." Thesis, Toulouse, INPT, 2012. http://www.theses.fr/2012INPT0020/document.
Full textAbstract:
Cette thèse porte sur différentes problématiques liées à la détection, l'ajustement et l'identification de structures elliptiques en images. Nous plaçons la détection de primitives géométriques dans le cadre statistique des méthodes a contrario afin d'obtenir un détecteur de segments de droites et d'arcs circulaires/elliptiques sans paramètres et capable de contrôler le nombre de fausses détections. Pour améliorer la précision des primitives détectées, une technique analytique simple d'ajustement de coniques est proposée ; elle combine la distance algébrique et l'orientation du gradient. L'identification d'une configuration de cercles coplanaires en images par une signature discriminante demande normalement la rectification Euclidienne du plan contenant les cercles. Nous proposons une technique efficace de calcul de la signature qui s'affranchit de l'étape de rectification ; elle est fondée exclusivement sur des propriétés invariantes du plan projectif, devenant elle même projectivement invarianteThis thesis deals with different aspects concerning the detection, fitting, and identification of elliptical features in digital images. We put the geometric feature detection in the a contrario statistical framework in order to obtain a combined parameter-free line segment, circular/elliptical arc detector, which controls the number of false detections. To improve the accuracy of the detected features, especially in cases of occluded circles/ellipses, a simple closed-form technique for conic fitting is introduced, which merges efficiently the algebraic distance with the gradient orientation. Identifying a configuration of coplanar circles in images through a discriminant signature usually requires the Euclidean reconstruction of the plane containing the circles. We propose an efficient signature computation method that bypasses the Euclidean reconstruction; it relies exclusively on invariant properties of the projective plane, being thus itself invariant under perspective
10
Fraser, Henry. "Copyright and culture : a qualitative theory." Thesis, University of Oxford, 2018. https://ora.ox.ac.uk/objects/uuid:cd4e645a-7e45-4309-bc68-e115e1fa306d.
Full textAbstract:
Copyright is conventionally justified as an incentive to produce and disseminate works of authorship. We can justify and theorise copyright more richly, not least because empirical evidence does not support the incentive narrative. Rather than focussing on quantitative matters such as the number of works incentivised and produced, we should consider copyright's qualitative influence on culture. A threshold objection to such an approach is the risk of cultural paternalism. This objection can be overcome. Rather than specifying paternalistic standards of merit for works, we can target the conditions under which their creation and consumption takes place. I argue, firstly, that we should adopt the following high-level principles: (i) that the conditions of creation and consumption of works should be conducive to democratic deliberation (democracy) and (ii) that they should facilitate the development of human capabilities (autonomy). Secondly, I propose that we pursue three mid-level objectives, which are helpful indicia of democracy and autonomy: - a fair and wide distribution of communicative and cultural power (inclusiveness); - diversity in the content and perspectives available to the public (diversity); and - conditions that permit authors and users of works to engage rigorously with the conventions of the media in which they operate (rigour). It is often said that copyright obstructs important qualitative objectives, like freedom of expression, and that we could better pursue these goals by weakening copyright and relying on non-proprietary alternatives. My approach produces a more optimistic, but also more complicated, view of copyright. While copyright's qualitative influence is not optimal, reductions in the strength and scope of copyright sometimes produces conditions and incentive structures that are worse for inclusiveness, diversity and rigour than stronger copyright. For example, both attention and wealth are highly concentrated in networked information economies driven by free sharing of content, and this is bad for diversity or inclusiveness. Online business models, based on surveillance of users' consumption of free works, are corrosive of autonomy and democracy. Merely removing copyright-based restrictions on the sharing of works is not a panacea for copyright's ills. A qualitative theory such as mine equips us to better understand and calibrate more richly the trade-offs involved in copyright policy decisions, and encourages us to treat copyright as part of a broader, qualitatively-oriented information and cultural policy.
11
Akbar, Muhammad Khalid. "Transport Phenomena in Complex Two and Three-Phase Flow Systems." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4897.
Full textAbstract:
Two and three-phase flow processes involving gas, liquid and solid, are common in nature and industry, and include some of the most complex and poorly-understood transport problems. In this research hydrodynamics, heat and mass transfer processes in complex two and three-phase flows were investigated. The interfacial surface area concentration in a short vertical column subject to the through flow of fiber-liquid-gas slurry was experimentally measured using the gas absorption technique. The experimental data were statistically analyzed for parametric effects, and were empirically correlated. The absorption of a gaseous species by a slurry droplet with internal circulation and containing reactive micro-particles was simulated, and parametrically studied. The micro-particles were found to enhance the absorption rate. The absorption rate was sensitive to droplet recirculation, and shrinkage of particles with time resulted in declining absorption rates. The transport of soot particles, suspended in laminar hot gas flowing in a tube, was modeled and parametrically studied. Due to coupled thermal radiation and thermophoresis, a radially-nonuniform temperature profile develops, leading to sharp, non-uniform radial soot-concentration profiles. The assumption of monodisperse particles leads to over-prediction of thermophoresis. The transport and removal of particles suspended in bubbles rising in a stagnant liquid pool were modeled based on a Eulerian – Monte Carlo method. The bubble hydrodynamics were treated in Eulerian frame, using the Volume-of-Fluid (VOF) technique, while particle equations of motion were numerically solved in Lagrangian frame. The bubbles undergo shape change, and have complex internal circulation, all of which influence the particle removal. Model predictions were also compared with experimental data. Using a resemblance between two-phase flow in microchannels, and in large channels at microgravity, a simple Weber number-based two-phase flow regime map was developed for microchannels. Based on the available air-water experimental data, a criterion for the prediction of conditions that lead to flow regime transition out of the stratified-wavy flow pattern in horizontal annular channels was proposed. The thermocapillary effects on liquid-vapor interface shape during heterogeneous bubble ebullition in microchannels were analytically studied.
12
Vogel, Harold. "Financial market bubbles : characteristics and theory." Thesis, University of London, 2008. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.534026.
Full text
13
Asaoka, Shintaro. "Essays on the Theory of Bubbles." Kyoto University, 2020. http://hdl.handle.net/2433/253470.
Full text
14
Yang, Qian. "Stock bubbles : The theory and estimation." Thesis, Brunel University, 2006. http://bura.brunel.ac.uk/handle/2438/3597.
Full textAbstract:
This work attempts to make a breakthrough in the empirical research of market inefficiency by introducing a new approach, the value frontier method, to estimate the magnitude of stock bubbles, which has been an interesting topic that has attracted a lot of research attention in the past. The theoretical framework stems from the basic argument of Blanchard & Watson’s (1982) rational expectation of asset value that should be equal to the fundamental value of the stock, and the argument of Scheinkman & Xiong (2003) and Hong, Scheinkman & Xiong (2006) that bubbles are formed by heterogeneous beliefs which can be refined as the optimism effect and the resale option effect. The applications of the value frontier methodology are demonstrated in this work at the market level and the firm level respectively. The estimated bubbles at the market level enable us to analyse bubble changes over time among 37 countries across the world, which helps further examine the relationship between economic factors (e.g. inflation) and bubbles. Firm-level bubbles are estimated in two developed markets, the US and the UK, as well as one emerging market, China. We found that the market-average bubble is less volatile than industry-level bubbles. This finding provides a compelling explanation to the failure of many existing studies in testing the existence of bubbles at the whole market level. In addition, the significant decreasing trend of Chinese bubbles and their co-moving tendency with the UK and the US markets offer us evidence in support of our argument that even in an immature market, investors can improve their investment perceptions towards rationality by learning not only from previous experience but also from other opened markets. Furthermore, following the arguments of “sustainable bubbles” from Binswanger (1999) and Scheinkman & Xiong (2003), we reinforce their claims at the end that a market with bubbles can also be labelled efficient; in particular, it has three forms of efficiency. First, a market without bubbles is completely efficient from the perspective of investors’ responsiveness to given information; secondly, a market with “sustainable bubbles” (bubbles that co-move with the economy), which results from rational responses to economic conditions, is in the strong form of information-responsive efficiency; thirdly, a market with “non-sustainable bubbles”, i.e. the bubble changes are not linked closely with economic foundations, is in the weak form of information-responsive efficiency.
15
Evripidou, Andria C. "Essays on speculative financial bubbles." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/49811/.
Full textAbstract:
This thesis contributes to the study of long-run relationships between financial assets. We develop a methodology for testing the hypothesis of co-bubbling behaviour in two series, employing a variant of the stationarity test of Kwiatkowski et al. (1992) which uses a conditional 'wild' bootsrap scheme to control size. We subsequently use our method to test for the presence of co-bubbles in a series of different markets. We look at commodities such as gold and silver and the housing market. There is a plethora of research on the efficacy of unit root tests for detecting explosive rational asset price bubbles. However, the migration of these bubbles and the possibility of co-bubbling behaviour of two series have seldom been researched. In the second chapter of this thesis we apply our model to the commodities market and find that the prices of gold and silver co-bubble in the period following the financial crisis. In the third chapter we investigate the migration of speculative housing bubbles between UK geographic regions. In the third chapter we analyse the co-bubbling relationship between rental and housing prices. We find that an explosive bubble behaviour in rental prices will lead to a bubble behaviour in house prices. The two series co-bubble over a period of time of around two years.
16
Makhankov, Vladimir, and Granados Máximo Agüero. "Bubbles Soliton Solutions in the φᶝ - Field Theory." Pontificia Universidad Católica del Perú, 2002. http://repositorio.pucp.edu.pe/index/handle/123456789/95741.
Full text
17
Pasini, Giulio. "Black holes and bubbled solutions in String Theory." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS218/document.
Full textAbstract:
Il existe des nombreuses solutions lisses dans le domaine de la théorie des cordes, caractérisées par une topologie non triviale (bulles) et sans sources localisées. Dans cette thèse nous analysons quelques-unes parmi les solutions les plus importantes avec les différents objectifs pour lesquels ils sont étudiés. Des solutions lisses en onze dimensions peuvent être interprétées comme microétats BPS de trou noir dans le cadre de la Fuzzball proposal. On peut promouvoir ces microétats à être quasi-BPS en plaçant de supertubes au minimum métastable à l’intérieur de ces solutions. Nous montrons que ces minima peuvent abaisser leur énergie lorsque les bulles se déplacent dans certaines directions dans l’espace des modules, ce qui implique que ces microétats quasi-BPS sont en fait instables. L’énergie dissipée par ces solutions correspond au rayonnement Hawking et on compare le taux d’émission et la fréquence à celles du trou noir correspondant. En modifiant la géométrie asymptotique de ces microétats on pourrait construire des microétats pour des trous noirs BPS sans charge électrique en cinq dimensions. Il faut donc trouver une nouvelle solution de supergravité en cinq dimensions dont la norme du vecteur de Killing passe de positive à nulle dans certaines régions. Nous construisons des exemples explicites où la norme du vecteur de Killing supersymétrique est une fonction réelle non-analytique telle que tous ses dérivés sont nulles à un point où le vecteur de Killing devient nul. Dans la solution de Lin-Lunin-Maldacena on trouve un mécanisme pour briser la supersymétrie similaire à celui utilisé pour les microétats quasi-BPS. Nous analysons l’énergie potentielle de branes M2 polarisés en branes M5. Lorsque les charges des M2 sont parallèles à ceux de la solution, nous trouvons des configurations stables. Lorsque les charges des M2 ne sont pas parallèles, nous trouvons des états métastables qui brisent la supersymétrie et nous analysons le processus de rayonnement d’énergie. Nous analysons aussi la solution de Klebanov-Strassler et construisons sa version T- duale dans la supergravité de type IIA. Pour cela une analyse approfondie est nécessaire pour choisir l’isomérie la plus appropriée. Notre construction est la première étape d’un programme pour tester la stabilité des antibranes dans la supergravité de type IIAThere exist many smooth solutions in String Theory characterized by a nontrivial topology threaded by fluxes and no localized sources. In this thesis we analyze some of the most important bubbled solutions along with the different purposes they are studied for. Some smooth, eleven-dimensional solutions can be interpreted as BPS black hole microstates in the context of the Fuzzball proposal. One can promote these to be microstates for near-BPS black holes by placing probe supertubes at a metastable minimum inside these solutions. We show that these minima can lower their energy when the bubbles move in certain directions in the moduli space, which implies that these near-BPS microstates are in fact unstable. The decay of these solutions corresponds to Hawking radiation and we compare the emission rate and frequency to those of the corresponding black hole. By modifying the asymptotic behavior of these microstates one could be able to construct microstates for five-dimensional BPS black holes with no electric charge. To do so one needs to find a new supergravity solution in five-dimensions whose Killing vector switches from timelike to null in some open regions. We construct explicit examples where the norm of the supersymmetric Killing vector is a real not-everywhere analytic function such that all its derivatives vanish at a point where the Killing vector becomes null. In the Lin-Lunin-Maldacena solution we find a supersymmetry-breaking mechanism similar to that used for near-BPS microstates. We analyze the potential energy of M2 probes polarized into M5 brane shells. When the charges of the probe are parallel to those of the solution we find stable configurations, while when the charges are opposite we find metastable states that break supersymmetry and analyze the decay process to supersymmetric configurations. We analyze also the Klebanov-Strassler solution and construct its T-dual version in Type IIA. This is done by just reconstructing the solution expanded on a small region of the deformed conifold, after a thorough analysis to choose the most suitable isometry. Our construction is the first step in a program to test the stability of antibranes in Type IIA backgrounds
18
Ramanan, Sisir. "Essays in asset price bubbles." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7357/.
Full textAbstract:
This thesis studies the field of asset price bubbles. It is comprised of three independent chapters. Each of these chapters either directly or indirectly analyse the existence or implications of asset price bubbles. The type of bubbles assumed in each of these chapters is consistent with rational expectations. Thus, the kind of price bubbles investigated here are known as rational bubbles in the literature. The following describes the three chapters. Chapter 1: This chapter attempts to explain the recent US housing price bubble by developing a heterogeneous agent endowment economy asset pricing model with risky housing, endogenous collateral and defaults. Investment in housing is subject to an idiosyncratic risk and some mortgages are defaulted in equilibrium. We analytically derive the leverage or the endogenous loan to value ratio. This variable comes from a limited participation constraint in a one period mortgage contract with monitoring costs. Our results show that low values of housing investment risk produces a credit easing effect encouraging excess leverage and generates credit driven rational price bubbles in the housing good. Conversely, high values of housing investment risk produces a credit crunch characterized by tight borrowing constraints, low leverage and low house prices. Furthermore, the leverage ratio was found to be procyclical and the rate of defaults countercyclical consistent with empirical evidence. Chapter 2: It is widely believed that financial assets have considerable persistence and are susceptible to bubbles. However, identification of this persistence and potential bubbles is not straightforward. This chapter tests for price bubbles in the United States housing market accounting for long memory and structural breaks. The intuition is that the presence of long memory negates price bubbles while the presence of breaks could artificially induce bubble behaviour. Hence, we use procedures namely semi-parametric Whittle and parametric ARFIMA procedures that are consistent for a variety of residual biases to estimate the value of the long memory parameter, d, of the log rent-price ratio. We find that the semi-parametric estimation procedures robust to non-normality and heteroskedasticity errors found far more bubble regions than parametric ones. A structural break was identified in the mean and trend of all the series which when accounted for removed bubble behaviour in a number of regions. Importantly, the United States housing market showed evidence for rational bubbles at both the aggregate and regional levels. In the third and final chapter, we attempt to answer the following question: To what extend should individuals participate in the stock market and hold risky assets over their lifecycle? We answer this question by employing a lifecycle consumption-portfolio choice model with housing, labour income and time varying predictable returns where the agents are constrained in the level of their borrowing. We first analytically characterize and then numerically solve for the optimal asset allocation on the risky asset comparing the return predictability case with that of IID returns. We successfully resolve the puzzles and find equity holding and participation rates close to the data. We also find that return predictability substantially alter both the level of risky portfolio allocation and the rate of stock market participation. High factor (dividend-price ratio) realization and high persistence of factor process indicative of stock market bubbles raise the amount of wealth invested in risky assets and the level of stock market participation, respectively. Conversely, rare disasters were found to bring down these rates, the change being severe for investors in the later years of the life-cycle. Furthermore, investors following time varying returns (return predictability) hedged background risks significantly better than the IID ones.
19
Leonard, S. R. "The propagation of nonlinear waves in a bubbly liquid." Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235334.
Full text
20
Narasimha, Reddy Vaka. "Comparison and Optimization of Insonation Strategies for Contrast Enhanced Ultrasound Imaging." Thesis, Linköpings universitet, Biomedicinsk instrumentteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-76646.
Full textAbstract:
Evolution of vulnerable carotid plaques are crucial reason for cerebral ischemic strokes and identifying them in the early stage can become very important in avoiding the risk of stroke. In order to improve the identification and quantification accuracy of infancy plaques better visualization techniques are needed. Improving the visualization and quantification of neovascularization in carotid plaque using contrast enhanced ultrasound imaging still remains a challenging task. In this thesis work, three optimization techniques are proposed, which showed an improvement in the sensitivity of contrast agents when compared to the conventional clinical settings and insonation strategies. They are as follows:1) Insonation at harmonic specific (2nd harmonic) resonance frequency instead of resonance frequency based on maximum energy absorption provides enhanced nonlinear contribution.2) At high frequency ultrasound imaging, shorter pulse length will provide improved harmonic signal content when compared to longer pulse lengths. Applying this concept to multi- pulse sequencing (Pulse Inversion and Cadence contrast pulse sequencing) resulted in increased magnitude of the remaining harmonic signal after pulse summations.3) Peak negative pressure optimization of Pulse Inversion and Cadence contrast pulse sequencing was showed to further enhance the nonlinear content of the backscattered signal from contrast microbubbles without increasing the safety limits, defined by the mechanical index.The results presented in this thesis are based on computational modeling (Bubblesim software) and as a future continuation we plan to verify the simulation results with vitro studies.
21
Magdelaine-Guillot, de Suduiraut Quentin. "Hydrodynamique des films liquides hétérogènes." Thesis, Sorbonne université, 2019. http://www.theses.fr/2019SORUS531.
Full textAbstract:
Revêtir une surface d’un film mince permet de lui conférer de nouvelles propriétés, comme en réduire les reflets ou améliorer sa résistance aux rayures. Une méthode pour produire ces revêtements est le dépôt par voie liquide : elle consiste à couvrir la surface avec un matériau dispersé dans un liquide puis à le sécher. Cette méthode permet de fonctionnaliser efficacement et rapidement de grandes surfaces. Bien qu'attrayante pour l’industrie verrière, la perspective d'une fonctionnalisation par voie liquide se heurte actuellement à l'apparition de défauts dans le film lors de son séchage, notamment des variations d'épaisseurs sur de grandes distances. Ces imperfections détériorent l'esthétique et les propriétés optiques de la surface. Dans cette thèse, nous apportons un éclairage sur l’apparition de ces défauts, en étudiant les écoulements générés lors du séchage de films liquides de mélanges binaires. En effet, l'évaporation du solvant peut induire des variations de composition qui génèrent en retour des gradients de tension à la surface du film qui le déstabilisent. La combinaison d'expériences modèles, de modélisations théoriques et de simulations numériques ont permis de mettre en évidence et de décrire quantitativement plusieurs régimes, qui correspondent aux différents effets limitant l’instabilité : la pesanteur, la pression de Laplace, l’homogénéisation latérale par diffusion des composées dans le film ou au contraire la stratification verticale de ces composés, causée par l’évaporation. Une étude indépendante a été menée sur la génération de trains de bulles lorsque de l’air est lentement injecté dans un bainCoating processes allow functionalizing a surface to obtain new properties, as anti-glare or anti-scratch. Amongst the various methods, wet coating, the process of spreading then drying a liquid layer containing a material of interest, is particularly appealing because of its efficiency and low cost. One key hurdle, however, is the possible apparition of defects in the film during the drying process, notably, thickness variations over large areas. These imperfections degrade the aspect and the optical properties of the surface. In this Ph.D. thesis, we shed light on the apparition of these defects, by studying the flows triggered by the evaporation in liquid films of binary mixtures. Indeed, the evaporation of the solvent can induce variations of composition which generate in return gradients of tension at the film surface which destabilize it. The combination of model experiments, theoretical modeling and numerical simulations allowed us to reveal and describe quantitatively several regimes, which correspond to the factor limiting the instability: gravity, Laplace pressure, lateral homogenization by diffusion of the compounds or by their vertical stratification due to the evaporation. An independent study has been lead on the generation of bubble trains when air is slowly injected in a bath
22
von, Coester Sorbas. "Bubbles and chaotic dynamics in economies with externalities." Thesis, London School of Economics and Political Science (University of London), 1996. http://etheses.lse.ac.uk/1427/.
Full textAbstract:
The present thesis deals with some consequences of the existence of external effects a la Homer, i.e. positive spillovers from the capital stock onto the efficiency of labour, and is mainly considering problems of discrete dynamics in the absence of any intrinsic (i.e. exogenous) shock. In the first chapter, using a one-sector three- period OLG model with borrowing constraints, it is shown that the standard result stating that, in the presence of externalities, any simple tax/subsidy policy undertaken to get rid of a bubble on an intrinsically useless asset creates an IOU which has exactly the same negative effects as the bubble itself, fails if there are agents who must borrow at some moment of their life. The other three chapters are mainly studying the problem of endogenous fluctuations in competitive equilibrium models. The second chapter looks at the possibility of Hopf bifurcations in the dynamical system characterizing a two-sector OLG economy meeting all neo-classical assumptions from the point of view of the private sector, and its ILA analogue : it demonstrates the existence of economies with stable closed orbits, derives some conditions on the parameters and compares the results to the continuous time modelization, concluding to a non robustness with regard to the time structure assumption. The third chapter is considering endogenous fluctuations in self-sustaining growth : using the same framework as previously, but under another assumption on the externalities, we establish that even if production inputs substitute perfectly and savings increase monotonically with the interest rate, cycles or even chaotic trajectories of the growth rate are possible. We show that this requires a strong externality in the consumption good sector in the absence of bubbles or sunspots, but not necessarily in their presence. Furthermore, we prove the existence of economies where, in the absence of any intrinsic uncertainty, the only possible equilibria involve bubbles or sunspots. The last and very short fourth chapter is a critical note on a recently published paper ; its main purpose is to show why current mathematical knowledge does not allow to sustain the claim of chaos in the proposed ILA framework.
23
Ignatieva, Ekaterina. "Adaptive Bayesian sampling with application to 'bubbles'." Connect to e-thesis, 2008. http://theses.gla.ac.uk/356/.
Full textAbstract:
Thesis (MSc(R)) - University of Glasgow, 2008.MSc(R). thesis submitted to the Department of Mathematics, Faculty of Information and Mathematical Sciences, University of Glasgow, 2008. Includes bibliographical references.
24
Fung, Tsan Sing Libon. "Rational speculative bubbles in a cross-sectional framework : a theory and simulation experiments." Thesis, Birkbeck (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369261.
Full text
25
Wong, Brehnen. "The Bayesian economic agent as a mechanism for asset-price bubbles." abstract and full text PDF (free order & download UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1460791.
Full text
26
Fitchett, Christian. "Asset price inflation- theory, history, and an alternative model." Oberlin College Honors Theses / OhioLINK, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1354820913.
Full text
27
Sola, Martin. "Essays on speculative attacks on fixed exchange rate regimes, speculative bubbles and endogenous switching regime estimation." Thesis, University of Southampton, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316309.
Full text
28
Pira, Jenni. "Homosexuellas upplevelser av våld : Utanför den underbara bubblan." Thesis, Mälardalen University, Department of Social Sciences, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-253.
Full textAbstract:
Syftet med den här studien har varit att undersöka hur homosexuella män upplever våld och risken att bli utsatt för våld bara på grund av att de är homosexuella. Den metod som användes för att utföra studien var Grundad teori. Detta för att på ett öppet sätt närma sig problemområdet utan föreställningar med syftet att skapa en ny teori. En bidragande orsak till teorivalet, då Grundad teoris huvudsyfte är att skapa nya teorier, var att forskning om homosexuellas utsatthet ofta beskrivs ur en heterosexuell synvinkel och handlar om vad de utsatts för och inte hur det upplevs. I resultatet framkom en komplex bild som å ena sidan visar att intervjupersonerna anpassar sig i vissa situationer på grund av risken att bli utsatt för våld, men å andra sidan anser de inte att våldet begränsar deras sätt att leva. Våldets närvaro leder till att personerna ifrågasätter och tvivlar på sig själva men har även lett till att personerna härdats och står för vilka de är. I sällskap med andra HBT-personer känner de sig helt trygga och där existerar inget våld alls, det är utanför den ”bubblan” som våldet finns och påverkar dem.
29
Sandberg, Fransson Emelie, and Petra Olgarsson. "Bubblan som sprack - Isabella Löwengrips kriskommunikation genom bloggen." Thesis, Umeå universitet, Institutionen för kultur- och medievetenskaper, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-169607.
Full textAbstract:
The research conducted in The Bubble That Burst – Isabella Löwengrip’s Crisis Communication Through Blog Posts aims to answer how Isabella Löwengrip attempted to save both her and her companies images during a crisis in the fall of 2019. Benoit’s Image Repair Theory and Goffman’s Self-Presentation Theory were combined to create the framework of this study. The material studied were blog posts uploaded onto her personal blog that mainly concerned the crisis during the months of October and November 2019. To demonstrate how the crisis evolved, additional material was added from February 2020. A textual rhetorical analysis method was used to investigate how Löwengrip aimed to persuade the blog’s readers that both she and her companies are still trustworthy. The results showed that Löwengrip used several Image Repair as well as rhetorical strategies. Löwengrip also changed her self-presentation during the crisis. Furthermore, it demonstrates how aware she is about her image. Additionally, the personal character of the blog medium makes the crisis communication more emotionally based and relationship building than traditional Image Repair and crisis communication efforts.
30
Křížová, Eliška. "Příčiny a souvislosti finanční krize v USA." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-113685.
Full textAbstract:
The diploma thesis investigates causes and progression of the financial crisis beginning in 2007 in the United States and leading in the economic recession. Theoretical part of the thesis describes business cycles and their explanations in accordance with the Austrian theory of the business cycle and other theories. Analytical part of the thesis explores the period before the crisis and significant events relevant to it. The main subject of the thesis are institutions and regulatory measures that have major importance for the U.S. real estate market -- including monetary and intervenionist policy of Fed, Community Reinvestment Act, government sponsored enterprises and three major rating agencies. The goal of the work is to provide a comprehensive view of the financial crisis and analyse main factors that influenced its creation -- credit expansion, mortgage market, Fed's monetary policy, bank behavior, etc. This thesis tries to demonstrate an inaccuracy of state inteventions and their impacts on the economy and market system.
31
Glade, William Daniel. "Way-Finding: A New Approach to Studying Digital Communications." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/8554.
Full textAbstract:
This work further develops the way-finding model first proposed by Pearson and Kosicki (2017) which examines the flow of information in the digital age. Way-finding systems are online systems that help individuals find information—i.e. social media, search engines, email, etc. Using a grounded theory methodology, this new framework was explored in greater detail. Way-finding theory was created using the context of the elaboration likelihood model, gatekeeping theory, algorithmic gatekeepers, and the existence of the filter bubble phenomenon. This study establishes the three basic pillars of way-finding theory: the user’s mindset when accessing way-finding systems, the perception of how popular way-finding systems function, and the perception of the information personalization process—particularly regarding algorithmic gatekeepers and their roles in creating the filter bubble phenomenon. These pillars and the relationships that exist between each constitute way-finding theory.
32
Ferreira, Murilo Resende. "Essays on banking theory and history of financial arrangements." reponame:Repositório Institucional do FGV, 2014. http://hdl.handle.net/10438/12421.
Full textAbstract:
Submitted by Murilo Resende Ferreira (muriloresende82@gmail.com) on 2014-10-28T15:22:42Z
No. of bitstreams: 1
Tesedoutoradomuriloresende.PDF: 806113 bytes, checksum: e6d9cfcc660128de80d20f44f9c5213e (MD5)Approved for entry into archive by BRUNA BARROS (bruna.barros@fgv.br) on 2014-11-10T11:34:49Z (GMT) No. of bitstreams: 1 Tesedoutoradomuriloresende.PDF: 806113 bytes, checksum: e6d9cfcc660128de80d20f44f9c5213e (MD5)
Approved for entry into archive by Marcia Bacha (marcia.bacha@fgv.br) on 2014-11-13T13:40:01Z (GMT) No. of bitstreams: 1 Tesedoutoradomuriloresende.PDF: 806113 bytes, checksum: e6d9cfcc660128de80d20f44f9c5213e (MD5)
Made available in DSpace on 2014-11-13T13:40:15Z (GMT). No. of bitstreams: 1 Tesedoutoradomuriloresende.PDF: 806113 bytes, checksum: e6d9cfcc660128de80d20f44f9c5213e (MD5) Previous issue date: 2014-06-27
This thesis contains two chapters, each one dealing with banking theory and the history of financiai arrangements. In Chapter 1, we extend a Diamond and Dybvig economy with imperfect monitoring of early withdrawals and make a welfare comparison between all possible allocations, as proposed by Prescott and Weinberg(2003) [37]. This imperfect monitoring is introduced by establishing indirect communication( trough a mean of payment) between the agents and the machine that is an aggregate of the financiai and the productive sector. The extension consists in studying allocations where a fraction of the agents can exploit imperfect monitoring and defraud the contracted arrangement by consuming more in the early period trough multiple means of payment. With limited punishment in the period of late consumption, this new allocation is called a separating allocation in contrast with pooling allocations where the agent with the ability of fraud is blocked from it by a costly mean of payment or by receiving enough future consumption to make fraud unattractive. The welfare comparison in the chosen range of parameters show that separating allocations are optimal for poor economies and pooling allocations for intermediary and rich ones. We end with a possible historical context for this kind of model, which connects with the historical narrative in chapter 2. In Chapter 2 we explore the quantitative properties of an early warning system for financiai crises based on the boom and bust framework described in more detail in appendix 1. The main variables are: real growth in equity and housing prices, the yield spread between the 10-year government bond and the 3-month interbank rate and the growth in total banking system assets. These variables display a higher degree of correct signals for recent crises (1984-2008) than comparable early warning systerns. Taking into account an increasing base-line risk ( due to increasing rates of credit expansion , lower interest rates and the accumulation of distortions) also proves to be informative and to help signaling crises in countries that did not go trough a great boom in previous years.
Esta tese contém dois capítulos, cada um lidando com a teoria e a história dos bancos e arranjos financeiros. No capítulo 1, busca-se extender uma economia Diamond-Dybvig com monitoramento imperfeito dos saques antecipados e realizar uma comparação do bem estar social em cada uma das alocações possíveis, como proposto em Presscott and Weinberg(2003). Esse monitoramento imperfeito é implementado a partir da comunicação indireta ( através de um meio de pagamento) entre os agentes e a máquina de depósitos e saques que é um agregado do setor produtivo e financeiro. A extensão consiste em estudar alocações onde uma fração dos agentes pode explorar o monitoramento imperfeito e fraudar a alocação contratada ao consumirem mais cedo além do limite, usando múltiplos meios de pagamento. Com a punição limitada no período de consumo tardio, essa nova alocação pode ser chamada de uma alocação separadora em contraste com as alocações agregadoras onde o agente com habilidade de fraudar é bloqueado por um meio de pagamento imune a fraude, mas custoso, ou por receber consumo futuro suficiente para tornar a fraude desinteressante. A comparação de bem estar na gama de parâmetros escolhida mostra que as alocações separadoras são ótimas para as economias com menor dotação e as agregadoras para as de nível intermediário e as ricas. O capítulo termina com um possível contexto histórico para o modelo, o qual se conecta com a narrativa histórica encontrada no capítulo 2. No capítulo 2 são exploradas as propriedade quantitativas de um sistema de previsão antecedente para crises financeiras, com as váriaveis sendo escolhidas a partir de um arcabouço de ``boom and bust'' descrito mais detalhadamente no apêndice 1. As principais variáveis são: o crescimento real nos preços de imóveis e ações, o diferencial entre os juros dos títulos governamentais de 10 anos e a taxa de 3 meses no mercado inter-bancário e o crescimento nos ativos totais do setor bancário. Essas variáveis produzem uma taxa mais elevada de sinais corretos para as crises bancárias recentes (1984-2008) do que os sistemas de indicadores antecedentes comparáveis. Levar em conta um risco de base crescente ( devido à tendência de acumulação de distorções no sistema de preços relativos em expansões anteriores) também provê informação e eleva o número de sinais corretos em países que não passaram por uma expansão creditícia e nos preços de ativos tão vigorosa.
33
Häggbom, Marcus, and Shayan Nafar. "Mean-Variance Portfolio Selection Accounting for Financial Bubbles: A Mean-Field Type Approach." Thesis, KTH, Matematisk statistik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-252299.
Full textAbstract:
The phenomenon of financial bubbles is known to have impacted various markets since the seventeenth century. Such bubbles are known to form when the market drastically overvalues the price of an asset, causing its market value to increase hyperbolically, only to suddenly collapse once the untenable perceived future prospects of the asset are realized. Hence, it remains crucial for investors to be able to sell off assets residing within a bubble before they burst and their value is significantly diminished. Thus, portfolio optimization methods capable of accounting for financial bubbles in stock dynamics is a field of great value and interest for market participants. Portfolio optimization with respect to the mean-field is a relatively novel approach to accounting for the bubble-phenomenon. Hence, this paper investigates a previously unattempted method of portfolio optimization, providing a mean-field solution to the mean-variance trade-off problem, as well as providing new definitions of stock dynamics capable of diverting investors from bubbles.Finansiella bubblor är ett fenomen som har påverkat marknader sedan 1600-talet. Bubblor tenderar att skapas när marknaden kraftigt övervärderar en tillgång vilket orsakar en hyperbolisk tillväxt i marknadspriset. Detta följs av en plötslig kollaps. Därför är det viktigt för investerare att kunna minska sin exponering mot aktier som befinner sig i en bubbla, så att risken för stora plötsliga förluster reduceras. Således är portföljoptimering där aktiedynamiken tar hänsyn till bubblor av högt intresse för marknadsdeltagare. Portföljoptimering med avseende på medelfältet är ett relativt nytt tillvägagångssätt för att behandla bubbelfenomen. Av denna anledning undersöks i detta arbete en hittills oprövad lösningsmetod som möjliggör en medelfältslösning till avvägningen mellan förväntad avkastning och risk. Där-utöver presenteras även ett antal nya modeller för aktier som kan bortleda investerare från bubblor.
34
Shen, Huanhuan. "Interferometric out-of-focus imaging and digital holography for the characterization of droplets or bubbles : theory, optical design, characterization of a flow, synchronized experiments." Rouen, 2014. http://www.theses.fr/2014ROUES015.
Full textAbstract:
Un simulateur original d'imagerie interférométrique en défaut de mise au point (ILIDS), permettant de modéliser n'importe quel système optique, est développé. Le formalisme de ce simulateur repose sur l'intégrale de Huygens-Fresnel généralisée. Le champ initial diffusé par des gouttes est simplifié par deux glare points. Un système original d'ILIDS, utilisant une configuration cylindrique, est conçu grâce au simulateur. Cette nouvelle configuration permet d'obtenir simultanément la position en trois dimensions et la taille des gouttelettes ou des bulles. Elle comprend une lentille cylindrique supplémentaire ayant un angle de rotation approprié autour de l'axe optique. Cette configuration anamorphique permet de lier l'orientation des franges d'interférence d'une part, et la forme de l'image en défaut de mise au point d'autre part, à la position axiale de la particule. Trois expériences sont réalisées successivement : l'observation de gouttes d'eau dans l'air, de bulles dans l'eau au sein d'un aquarium cubique et de bulles dans la glycérine située dans un canal cylindrique. Les comparaisons entre simulations et expériences montrent des résultats cohérents. Les précisions des positions axiales et des talles obtenus par la configuration cylindrique d'ILILDS sont évaluées expérimentalement. Les positions axiales sont validées par une comparaison avec leurs valeurs calibrées, tandis que les diamètres sont vérifiés grâce à une configuration couplée deux techniques: holographie numérique sur l'axe et configuration cylindrique d'ILIDSAn original simulator of Interferometric Laser Imaging for Droplet Sizing (ILIDS), allowing predicting the image patterns obtained by any imaging system, is developed. The formalism of the simulator relies on the generalized Huygens-Fresnel integral. The initial field scattered by the droplet is simplified by two glare points. An original ILIDS system is designed due to the simulator. The advantage of this configuration is that the three dimensional locations and sizes of droplets can be obtained simultaneously. The cylindrical ILIDS configuration includes a supplemental cylindrical lens rotated in a proper angle with respect to the axis of imaging system. The anamorphic configuration allows to change the orientation of the fringes and the form of the out-of-focus image with respect to the axial location of the particle. Three experiments are successively conducted: water droplets in air, bubbles in water at cubic aquarium and bubbles in glycerin at cylindrical channel. The comparisons of the simulations and experiments show good consistence. The precisions of the axial location and diameter obtained by cylindrical ILIDS technique are evaluated experimentally. The axial locations obtained by cylindrical ILIDS configuration are validated by comparing them with calibrated values, while the diameters are validated due a synchronized experiment coupling Digital In-Line Holography technique and cylindrical ILIDS technique
35
Choo, Chang Yuan Lawrence. "Iterative reasoning and markets : three experiments." Thesis, University of Exeter, 2014. http://hdl.handle.net/10871/15825.
Full textAbstract:
We present in this thesis three distinct experiments, studying issues in behavioural economics and finan- cial market. In the first paper, we study the level-k reasoning model in an experimental extension of Arad and Rubinsten (2012) “11-20 Money Request Game”. In the second paper, we introduce an experimental design where traders can buy or sell the rights for performing complex decisional task. The design seeks to test the allocative efficiency of markets. In the third paper, we introduce an Arrow-Debreu market where traders have diverse and partial information about the true state of nature. The design seeks to test the Rational Expectations model’s prediction that all relevant information will be aggregated into market prices.
36
Critchfield, Brian L. "Statistical Methods For Kinetic Modeling Of Fischer Tropsch Synthesis On A Supported Iron Catalyst." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1670.pdf.
Full text
37
Piel, Konstanze. "Ökonomie des Nichtwissens : Aktienhype und Vertrauenskrise im Neuen Markt /." Frankfurt/Main [u.a.] : Campus Verl, 2003. http://www.gbv.de/dms/zbw/358063833.pdf.
Full text
38
Engvall, Aida, and Viviann Le. "Misstag eller konspiration? : En kvalitativ gestaltningsanalys av Fria Tiders skildringar av mordet på före detta statsminister Olof Palme." Thesis, Linnéuniversitetet, Institutionen för medier och journalistik (MJ), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-75796.
Full textAbstract:
The Swedish prime minister, Olof Palme was murdered in the middle of the street in the heart of Stockholm, by an unknown perpetrator on the 28th of February 1986. Even though it has been 32 years since the death of the former prime minister, a keen interest of the murder within the media still exists and has not decreased over the years. By conducting a qualitative text analysis, this paper examined how the murder of Olof Palme is described in an alternative medium; Fria Tider. The aim of this study is to problematize citizen journalism in Sweden. With the basis of the framing theory and agenda setting, eight texts were chosen from the alternative medium Fria Tider, an online newspaper. The authors conducted a framing analysis to identify which frameworks were most prominent in the way of describing the murder. The result of this study showed that three frames dominated; a conspiracy of several actors, the police's responsibility, and the solution is near. The authors found that Fria Tider produced several individuals and institutions as suspected of the murder of Olof Palme in these frameworks. While these frameworks can be seen as problematic, this study cannot conclude that it is problematic to read opinions other than what traditional media give. Therefore, this study cannot problematize citizen journalism.
39
Lin, Kun Nan, and 林坤南. "Shock-wave theory for single-bubble sonoluminescence." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/42678070910988956059.
Full textAbstract:
碩士國立清華大學
物理系
101
To understand the light emission mechanism in single-bubble sonoluminescence experiment, the spectra are a key source of information. They already reveal that the light emission region is smaller than the bubble size. Theorists have been trying hard to predict the highest temperature and the size of light emission region. This is the main goal of my thesis work. According to the shock-wave theory, we analyzed the propagation of the shock wave. Then we take into account the van der Waals force and energy conservation to both analytically and numerically elucidate how the light emission region and its temperature distribution evolve. In the end, we are able to obtain the highest temperature intuitively and qualitatively.
40
"Incorporating Social Network Variables into Relational Turbulence Theory: Popping the Dyadic Bubble." Doctoral diss., 2018. http://hdl.handle.net/2286/R.I.49170.
Full textAbstract:
abstract: Relational turbulence theory (RTT) has primarily explored the effects of relational uncertainty and partner interdependence on relational outcomes. While robust, the theory fails to account for uncertainties and perceived interdependence stemming from extra-dyadic factors (such as partners’ social networks). Thus, this dissertation had two primary goals. First, scales indexing measures of social network-based relational uncertainty (i.e., network uncertainty) and social network interdependence are tested for convergent and divergent validity. Second, measurements of network uncertainty and interdependence are tested alongside measures featured in RTT to explore predictive validity. Results confirmed both measurements and demonstrated numerous significant relationships for turbulence variables. Discussions of theoretical applications and future directions are offered.Dissertation/Thesis
Doctoral Dissertation Communication Studies 2018
41
Brainerd, Andrew Eric. "Topics in Cosmology and Quantum Mechanics: Entanglement Harvesting and Cosmic Bubble Collisions." Thesis, 2017. https://doi.org/10.7916/D8PV6XNT.
Full textAbstract:
This dissertation explores two topics located in the intersection of quantum mechanics and cosmology. Entanglement harvesting is a phenomenon in which quantum entanglement can develop between the states of two Unruh-DeWitt detectors travelling through spacetime by way of mutual interaction with a scalar quantum field. I numerically explore entanglement harvesting of Unruh-DeWitt detectors in Minkowski space travelling with constant acceleration, generalizing previous analytical results which held only in a limiting case. Cosmic bubble collisions arise in inflationary cosmology as a mechanism to begin reheating at the end of inflation. I extend the previously proposed theory of boom and bust inflation which relies on the existence of a large extra dimension by exploring particular inflationary models in which reheating need not begin the first time that two bubble walls collide. This allows for a smaller lower bound on the size of the compact extra dimension in the boom and bust proposal.
42
Vimalnath, Pratheeba. "A Comparison between Singleton and Portfolio Patent Valuation in Auction Mode of Patent Transaction." Thesis, 2016. http://hdl.handle.net/2005/3076.
Full textAbstract:
Patents have become a direct source of revenue, apart from providing legal protections for inventions. A patent generates revenue in its patented form through licensing or sell-out. Three challenges confront this shift in use of patents as direct revenue generators especially in the context of patent sale. First, the challenge of estimating the price a patent fetches in a sale (referred as ‗patent value‘) remains scarcely addressed owing to the intangible nature of patents and lack of patent sale data in public domain. Secondly, the variations in price and the method used to estimate the price while selling a patent individually (called as a singleton) or in a group along with other patents (called as portfolio) are little understood. Thirdly, literature focus so far has been on the static dimensions of patent value determinants leaving scope for researching the time varying dynamic nature of potential value determinants.
This thesis aims to systematically address the above challenges and research gaps through five specific research objectives pertaining to the following four aspects of patent sale:
(1) Successful sale aspect of patent lots in an auction (Research objective 1)
Research objective 1: To explore the determinants of successful sale of singletons and portfolios.
(2) Selling strategy aspect of the sold patents (Research objective 2)
Research objective 2: To characterize the singleton and portfolio patent lots successfully sold in an auction.
(3) Time dynamic aspect of factors influencing price (Research objectives 3 & 4) Research objective 3: To investigate the effect of time dynamic nature of patent age on the selling prices of singletons and portfolios.
Research objective 4: To understand the effect of time dynamic trend of technological importance (TI) and patent class trend on selling prices of singletons and portfolios.
(4) Valuation aspect (Research objective 5)
Research objective 5: To identify the determinants of selling prices of singletons and portfolios.
In this thesis, we use a combination of patent bibliometric and market based approach to study various aspects of singleton and portfolio patent sale incorporating the time dynamic aspect. A set of US patents auctioned by an US auction firm, called Ocean Tomo, is used as sample. The sample was dominated by patents from Computer & Communication field.
The research findings showed significant differences in the characteristics of sold and unsold lots both in the case of singletons and portfolios. Amongst the sold lots, singletons were found to include more novel (lesser patent backward citations) and technology specific (higher C&C technology scope) patents than the portfolios sold. Further investigation on the variation in selling prices fetched by singletons and portfolios showed portfolios fetching significantly higher prices than singletons at the lot level. Interestingly, at a granular level, the equation reversed with singletons showing significantly higher price compared to the average price per individual US patent member within the portfolio.
Along the time dynamic aspect, the existence of an optimal age to sell patents for higher prices is evidenced especially in the case of singletons from C&C technology field. The optimal age was found to be around 10 year 2 months of age from grant of singletons. No such optimal age was identified for portfolios. The growth trend analysis of the forward citations (technological importance of patent) and the patent applications filed within the specific patent class of a patent (attractiveness of patent class) illustrated the significance of the patent class trend in explaining variation in selling price of singletons.
Finally, the valuation models of singletons and portfolios showed singletons being valued more on the patent related characteristics unlike portfolios which were valued based on the all three aspects – patent, seller and bundling.
In summary, the novelty of the thesis resides in the (1) incorporation of new set of variables namely forward citation diversity, forward citations trend, patent class trend, technology scope and portfolio type in understanding patent price (2) treatment of time dynamic variables in understanding patent value and (3) focus on portfolio analysis through independent analysis of singleton and portfolio selling prices.
43
柯順雄. "The empirical evidence of bubbles theory in Taiwan stock market: testing the existence and characteristics of bubbles." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/24803810037645781655.
Full text
44
Alizadeh, Mohsen. "Experimental investigation of shock wave - bubble interaction." Doctoral thesis, 2010. http://hdl.handle.net/11858/00-1735-0000-0006-B4C2-3.
Full text
45
Tiwari, G. P., M. Laghate, and R. S. Mehrotra. "A Theory for the Surface Induced Growth of Helium Gas Bubbles in Irradiated and Annealed Copper - Boron Alloys." 2017. https://ul.qucosa.de/id/qucosa%3A31552.
Full textAbstract:
Neutron irradiated copper-boron alloys are employed to study the mutual interaction between metallic crystalline lattices and inert gases. Inert gases precipitate to form gas bubbles and their growth
induces dilation of the matrix. This dilation, technically designated as swelling, affects the structural integrity of nuclear fuels during their service. The estimated enthalpy of solution of helium in copper is 5.5 eV/atom. As a Consequence, its solubility in the copper matrix is extremely poor and it cannot enter a copper based matrix via any thermo-chemical route. Hence, recourse to a nuclear reaction is taken to impregnate copper with helium. Helium is produced in situ through neutron irradiation in copper-boron alloys as a result of (n, alpha) nuclear reaction between boron atoms and neutrons. The characteristic feature
of the growth of helium gas bubbles driven by isothermal annealing of the metallic matrix is that their rate of growth is highly sensitive to the distance of the bubbles from the external surface of the specimen. The growth of gas bubbles as a function of time and temperature is modulated by the flow of vacancies from the free surface of the specimen. A theory for the surface induced growth of helium gas bubbles in the neutron irradiated copper-boron alloys is presented here.
46
Savard, Antoine. "Stabilité des bulles de masse négative dans un espace-temps de de Sitter." Thèse, 2019. http://hdl.handle.net/1866/23817.
Full textAbstract:
L'existence de la masse négative a un sens parfaitement physique du moment que les conditions d'énergie dominante sont satisfaites par le tenseur énergie-impulsion correspondant. Jusqu'à maintenant, seules des configurations de masses négatives avaient été trouvées. On démontre l'existence de bulles de masse négative stables dans un espace-temps qui s'approche asymptotiquement d'un espace-temps de de Sitter. Les bulles sont des solutions aux équations d'Einstein qui correspondent à une région intérieure qui contient une distribution de masse spécifique séparée par une coquille mince de l'espace-temps à masse négative de Schwarzschild-de Sitter à l'extérieur.
Ensuite, on applique les conditions de jonction d'Israel à la frontière de la bulle ce qui impose la conservation d'énergie-impulsion à travers la surface. Les conditions de jonction donnent une équation pour un potentiel pour le rayon de la bulle qui dépend de la distribution de masse à l'intérieur, ou vice versa.
Finalement, on trouve un potentiel qui aboutit à une solution stable, statique et non-singulière, ce qui crée une distribution de masse interne qui satisfait les conditions d'énergie dominante partout à l'intérieur. Cependant, la bulle ne satisfait pas ces conditions. De plus, on trouve une solution stable, statique et non-singulière pour une géométrie interne de de Sitter pure. La solution est fondamentalement différente: elle requiert que la densité d'énergie de la bulle change avec le rayon. La condition d'énergie dominante est satisfaite partout.Negative mass makes perfect physical sense as long as the dominant energy condition is satisfied by the corresponding energy-momentum tensor. Until now, only configurations of negative mass have been found. We demonstrate the existence of stable, negative-mass bubbles in an asymptotic de Sitter space-time. The bubbles are solutions of the Einstein equations which correspond to an interior region of space-time containing a specific distribution of mass separated by a thin wall from the exact, negative mass Schwarzschild-de Sitter space-time in the exterior. Then, we apply the Israel junction conditions at the wall which impose the conservation of energy and momentum across the wall. The junction conditions give rise to an effective potential for the radius of the wall that depends on the interior mass distribution, or vice versa. Finally, we find a potential that gives rise to stable, non-singular, static solutions, which yields an interior mass distribution that everywhere satisfies the dominant energy condition. However, the energy momentum of the wall does not satisfy the dominant energy condition. Moreover, we find a stable, non-singular, static solution for a pure de Sitter geometry inside the bubble. The solution is fundamentally different: the energy density of the bubble is no longer a constant, but now varies with the radius. The dominant energy condition is everywhere satisfied.
47
Tucci, Stacey L. "Effects of Theory of Mind Training on the False Belief Understanding of Deaf and Hard of Hearing Students in Prekindergarten and Kindergarten." 2014. http://scholarworks.gsu.edu/epse_diss/99.
Full textAbstract:
Data from a growing number of research studies indicate that children with hearing loss are delayed in Theory of Mind (ToM) development when compared to their typically developing, hearing peers. While other researchers have studied the developmental trajectories of ToM in school-age students who are deaf and hard of hearing (DHH), a limited number have addressed the need for interventions for this population. The present study extends the current research on ToM interventions to the PreKindergarten and Kindergarten levels. This study used a single-case multiple-baseline multiple-probe across skills design with replications across classrooms to examine the effects of a ToM intervention on participants’ false belief understanding as well as outcomes on a near generalization measure (i.e., Sally-Anne Task, Baron-Cohen, Firth, Leslie, 1985) and a far generalization measure (i.e., five-task ToM developmental scale, Wellman & Liu, 2004). A thought bubble intervention (i.e., a visual representation of what people are thinking) developed by Wellman and Peterson (2013) was modified in key areas: (a) participants were substantially younger than the population in the original study and thus required a pre-teaching phase addressing vocabulary and materials, (b) manipulable materials were created from the description provided in the Wellman and Peterson (2013) study along with parallel materials used in assessment probes, (c) a certified teacher of DHH children provided direct instruction to participants in a small group setting, (d) study length was increased to 25 weeks, and (e) methodological design change (i.e., group design to single-case design). These modifications addressed the need for evidence-based ToM interventions that are both proactive and easily implemented by teachers in a classroom setting. Results from the single-case design portion of the study indicate a functional relation between the thought bubble intervention and the participants’ acquisition of the targeted skills in each stage, although progress was not uniform. Results from the pre-post assessments indicate that the children did make progress up the scale, however, children who used spoken language tended to proceed faster through the stages than those who used sign language. These results inform the field in regard to the efficacy and feasibility of a ToM intervention for young DHH children.
48
Silva, Rui Miguel Constantino da. "The investor behavior on extreme situations of speculation and crash: a game theory approach based on the iterated prisoner’s dilemma." Master's thesis, 2011. http://hdl.handle.net/10071/12422.
Full textAbstract:
JEL Classification System: C73; G01The present dissertation aims to develop an analysis to the investor behavior on situations of speculation and crash on stock markets. An approach to the main investor behavioral features is made, mainly the ones related with cognitive and decision-making questions in order to obtain an individual and the aggregate behavioral profile of the investor on situations of extreme events. Thus, the present work is structured on two main parts. The first one is related to the literature review about the definition of the investor, mainly considering questions linked to rationality, information processing, motivations and needs and properties which define the decision making process; contextualized the main problem of the study. In this part the events that leaded to the stock crashes of 1929 and 2000 were selected. On the second part (from Chapter 4) a concrete analysis to the behavior of the investor is made for these events through game theory, particularly, making use of the Iterated Prisoner’s Dilemma model to a sub-game that possesses as the main problem the existence, between players, of cooperation attitudes, aiming the maintenance of their positions or even their investments on overvalued assets, which are the main cause of the speculative bubble, and defection, which implies the opposite posture. The possibility of cooperation among the agents is inferred for a brief period of time, being demonstrated also that the equilibria were unstable for these situations.
A presente dissertação visa proceder a um estudo do comportamento do investidor em situações de especulação e crash nos mercados bolsistas. É efectuada uma abordagem às características comportamentais do investidor, sobretudo as que se relacionam com questões do foro cognitivo e de escolha, de modo a obter um perfil tanto individual como agregado do comportamento do investidor em eventos extremos. Deste modo o presente trabalho encontra-se estruturado em duas partes. A primeira relaciona-se com uma abordagem à literatura existente relativamente à definição do investidor, particularmente nas questões vocacionadas com a racionalidade, processamento de informação, motivações e necessidades e propriedades que influenciam a tomada de escolha, com uma definição do problema subjacente ao presente estudo, seleccionando para tal os eventos que implicaram os crashes bolsistas de 1929 e 2000. Numa segunda parte (a partir do Capitulo 4) é efectuada uma análise concreta ao comportamento do investidor nesses mesmos eventos via modelação pela teoria dos jogos, em particular, através da aplicação do Dilema do Prisioneiro Iterativo a um sub-jogo que possui como problema-base a existência entre jogadores de atitudes de cooperação, para manutenção das posições ou mesmo investimento em activos sobreavaliados e que são o foco da bolha especulativa, e não cooperação, que implica a atitude contrária. Acabou por ser inferida a possibilidade de existência de cooperação entre os agentes por um curto espaço de tempo, tendo os equilíbrios obtidos demonstrado instabilidade.
49
Woolman, Stu (Stuart Craig). "The Selfless Constitution : experimentation&flourishing as the foundations of South Africa's basic law." Thesis, 2007. http://hdl.handle.net/2263/27527.
Full textAbstract:
The way the vast majority of us think about the self, consciousness and free will is incorrect – dramatically out of step with what the majority of neuroscientists, cognitive psychologists scientists and analytic philosophers have to say about those subjects. One consequence of these erroneous views is that the manner in which the majority of us understand ‘freedom’ – as a metaphysical term and as a political concept -- is sharply at odds with how things actually are. We replicate similar kinds of errors when we think about how various forms of human association are constructed and how change actually occurs within such associations. Once again, epistemological fallacies with regard to social theory have the consequence of leading us to attribute far greater ‘freedom’ to groups than they actually possess. This second misattribution of autonomy results in institutional political arrangements and constitutional doctrines at odds with what we know about the human condition. As things stand, the various models of political theory with which the South African Constitutional Court operates rest upon a belief that the rights and freedoms enshrined in the Final Constitution should enable individuals to exercise relatively unfettered control over decisions about the intimate relationships and the various practices deemed critical to their self-understanding. However, individual autonomy as a foundation for constitutional theory overemphasizes dramatically the actual space for self-defining choices. In truth, our experience of personhood, of self-consciousness, is a function of a complex set of narratives over which we exercise little in the way of (self) control. The involuntary and arational nature of identity formation – at the level of both the individual and the social -- requires a constitutional theory that supplants the model of a rational individual moral agent which undergirds much of our current jurisprudence with a vision of the self that is more appropriately located within and determined by the associations to which we all belong. Despite the involuntary and arational nature of identity formation, we can live within communities that determine the greater part of the meaning we make, and still remain committed to the possibility of significant change (for the better) within those communities. This thesis then goes on to explain how a commitment to experimentalism in the political domain, when married to a robust conception of basic entitlements and citizenship, services human flourishing. (To expand the conditions for flourishing, however, is not to make us metaphysically ‘free’ to ‘will’ our actions: a commitment to flourishing reflects an attempt to create an environment in which all inhabitants of South Africa have the opportunity to live lives worth valuing.) Experimental constitutionalism dovetails with a very modest, naturalized account of flourishing because both accounts (1) take the radical givenness of existing constitutive attachments seriously; (2) recognize the boundedness of individual and collective rationality; and (3) describe various kinds of feedback mechanisms that allow for error correction and the enhancement of the conditions of being. Experimental constitutionalism, in particular, enables more citizens to see what ‘works’ and what doesn’t – both with respect to the means and the ends of our existence. Experimental constitutionalism offers the promise of improving the conditions for being by suggesting a range of alterations in constitutional doctrine and a host of changes in the manner in which many political institutions operate. In South Africa, the innovations associated with experimental constitutional design embrace: (1) a doctrine of constitutional supremacy that maintains a meaningful equilibrium with a doctrine of separation of powers, and thus sets relatively clear guidelines for how authority for constitutional interpretation might best be shared by the judiciary, the legislature, the executive and non-state-actors; (2) the use of various standard judicial mechanisms – such as cost orders, court procedures, amici and intervenors, expanded constitutional jurisdiction and structural injunctions – to create bubbles of participatory democracy better able (than courts or legislatures) to resolve various kinds of polycentric conflict; (3) an approach to limitations analysis that provides a better process than ‘balancing’ for experimentalist adjudication; and (4) greater roles for Chapter 9 Institutions with respect to investigation, information-sharing and norm-setting; and (5) a principle of democracy that invites public participation in law-making that will both elicit better information about which government policies work best and effect widespread reflection about the meaning of those constitutional norms that govern our lives. The thesis then (a) mines the brief historical record of two important policy areas – Housing and Education – to show how the principles of experimental constitutionalism have already been put to work and (b) re-examines six Constitutional Court cases to demonstrate how the dual commitment to experimental constitutionalism and flourishing might generate more optimal outcomes.Thesis (LLD)--University of Pretoria, 2008.
Public Law
unrestricted
50
Walden, Johan. "Investing when knowledge is limited : essays in financial economics /." 2005. http://www.gbv.de/dms/zbw/547361629.pdf.
Full text