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1
Li, Xiaochun. "Uniform bounds for the bilinear Hilbert transforms /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3025634.
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Khan, Mumtaz Ahmad. "On fractional integral operators of three variables and integral transforms." Pontificia Universidad Católica del Perú, 2012. http://repositorio.pucp.edu.pe/index/handle/123456789/96049.
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The present paper is a continuation to authors paper [11]where three variable analogues of certain fractional integraloperators of M. Saigo were investigated. This paper dealswith the effect of operating three variable analogues of Mellinand Laplace transforms on these three variable analogues offractional integral operators of the earlier paper.
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Khan, Mumtaz Ahmad, and Abukhammash Ghazi Salama. "On certain fractional integral operators of two variables and integral transforms." Pontificia Universidad Católica del Perú, 2014. http://repositorio.pucp.edu.pe/index/handle/123456789/97226.
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The present paper is in continuation to authors earlier paper {9} where two variable analogues of certain fractional integral operators of M. Saigo were investigated. This paper deals with the effect of operating two variable analogues of Mellin and Laplace transforms on these two variable analogues of fractional integral operators of the earlier paper.
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Alkauskas, Giedrius. "Integral transforms of the Minkowski question mark function." Thesis, University of Nottingham, 2008. http://eprints.nottingham.ac.uk/10641/.
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The Minkowski question mark function F(x) arises as a real distribution function of rationals in the Farey (alias, Stern-Brocot or Calkin-Wilf) tree. In this thesis we introduce its three natural integral transforms: the dyadic period function G(z), defined in the cut plane; the dyadic zeta function zeta_M(s), which is an entire function; the characteristic function m(t), which is an entire function as well. Each of them is a unique object, and is characterized by regularity properties and a functional equation, which reformulates in its own terms the functional equation for F(x). We study the interrelations among these three objects and F(x). It appears that the theory is completely parallel to the one for Maass wave forms for PSL_2(Z). One of the main purposes of this thesis is to clarify the nature of moments of the Minkowski question mark function.
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Kerr, Fiona Helen. "Fractional powers of integral transforms for classical and generalized functions." Thesis, University of Strathclyde, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303285.
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Ramaseshan, Karthik. "Microlocal analysis of the doppler transform on R³ /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/5739.
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Sanja, Kostadinova. "Some classes of integral transforms on distribution spaces and generalized asymptotics." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2014. https://www.cris.uns.ac.rs/record.jsf?recordId=87772&source=NDLTD&language=en.
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In this doctoral dissertation several integral transforms are discussed.The first one is the Short time Fourier transform (STFT). We present continuity theorems for the STFT and its adjoint on the test function space K1(ℝn) and the topological tensor product K1(ℝn) ⊗ U(ℂn), where U(ℂn) is the space of entirerapidly decreasing functions in any horizontal band of ℂn. We then use such continuity results to develop a framework for the STFT on K'1(ℝn). Also, we devote one section to the characterization of K’1(ℝn) and related spaces via modulation spaces. We also obtain various Tauberian theorems for the short-time Fourier transform.Part of the thesis is dedicated to the ridgelet and the Radon transform. We define and study the ridgelet transform of (Lizorkin) distributions and we show that the ridgelet transform and the ridgelet synthesis operator can be extended as continuous mappings Rψ : S’0(ℝn) → S’(Yn+1) and Rtψ: S’(Yn+1) → S’0(ℝn). We then use our results to develop a distributional framework for the ridgelet transform that is, we treat the ridgelet transform on S’0(ℝn) via a duality approach. Then, the continuity theorems for the ridgelet transform are applied to discuss the continuity of the Radon transform on these spaces and their duals. Finally, we deal with some Abelian and Tauberian theorems relating the quasiasymptotic behavior of distributions with the quasiasymptotics of the its Radon and ridgelet transform.The last chapter is dedicated to the MRA of M-exponential distributions. We study the convergence of multiresolution expansions in various test function and distribution spaces and we discuss the pointwise convergence of multiresolution expansions to the distributional point values of a distribution. We also provide a characterization of the quasiasymptotic behavior in terms of multiresolution expansions and give an MRA sufficient condition for the existence of α-density points of positive measures.U ovoj doktorskoj disertaciji razmotreno je nekoliko integralnih transformacija. Prva je short time Fourier transform (STFT). Date su i dokazane teoreme o neprekidnosti STFT i njena sinteza na prostoru test funkcije K1(ℝn) i na prostoru K1(ℝn) ⊗ U(ℂn), gde je U(ℂn) prostor od celih brzo opadajućih funkcija u proizvoljnom horizontalnom opsegu na ℂn. Onda, ovi rezultati neprekidnosti su iskorišteni za razvijanje teorije STFT na prostoru K’1(ℝn). Jedno poglavlje je posvećeno karakterizaciji K’1(ℝn) sa srodnih modulaciskih prostora. Dokazani su i različiti Tauberovi rezultata za STFT. Deo teze je posvećen na ridglet i Radon transformacije. Ridgelet transformacija je definisana na (Lizorkin) distribucije i pokazano je da ridgelet transformacija i njen operator sinteze mogu da se prošire kako neprekidna preslikava Rψ : S’0(ℝn) → S’(Yn+1) and RtΨ: S’(Yn+1) → S’0(ℝn). Ridgelet transformacija na S’0(ℝn) je data preko dualnog pristupa. Naše teoreme neprekidnosti ridgelet transformacije su primenjene u dokazivanju neprekidnosti Radonove transformacije na Lizorkin test prostorima i njihovim dualima. Na kraju, dajemo Abelovih i Tauberovih teorema koji daju veze izmedju kvaziasimptotike distribucija i kvaziasimptotike rigdelet i Radonovog transfomaciju.Zadnje poglavje je posveceno multirezolucijskog analizu M - eksponencijalnih distrubucije. Proucavamo konvergenciju multirezolucijkog razvoja u razlicitih prostori test funkcije i distribucije i razmotrena je tackasta konvergencija multirezolucijkog razvoju u tacku u distributivnog smislu. Obezbedjena je i karakterizacija kvaziasimptotike u pogled multirezolucijskog razvoju i dat dovoljni uslov za postojanje α-tacka gustine za pozitivne mere.
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Dušanka, Perišić. "On Integral Transforms and Convolution Equations on the Spaces of Tempered Ultradistributions." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 1992. https://www.cris.uns.ac.rs/record.jsf?recordId=73337&source=NDLTD&language=en.
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In the thesis are introduced and investigated spaces of Burling and of Roumieu type tempered ultradistributions, which are natural generalization of the space of Schwartz’s tempered distributions in Denjoy-Carleman-Komatsu’s theory of ultradistributions. It has been proved that the introduced spaces preserve all of the good properties Schwartz space has, among others, a remarkable one, that the Fourier transform maps continuposly the spaces into themselves.In the first chapter the necessary notation and notions are given.In the second chapter, the spaces of ultrarapidly decreasing ultradifferentiable functions and their duals, the spaces of Beurling and of Roumieu tempered ultradistributions, are introduced; their topological properties and relations with the known distribution and ultradistribution spaces and structural properties are investigated; characterization of the Hermite expansions and boundary value representation of the elements of the spaces are given.The spaces of multipliers of the spaces of Beurling and of Roumieu type tempered ultradistributions are determined explicitly in the third chapter.The fourth chapter is devoted to the investigation of Fourier, Wigner, Bargmann and Hilbert transforms on the spaces of Beurling and of Roumieu type tempered ultradistributions and their test spaces.In the fifth chapter the equivalence of classical definitions of the convolution of Beurling type ultradistributions is proved, and the equivalence of, newly introduced definitions, of ultratempered convolutions of Beurling type ultradistributions is proved.In the last chapter is given a necessary and sufficient condition for a convolutor of a space of tempered ultradistributions to be hypoelliptic in a space of integrable ultradistribution, is given, and hypoelliptic convolution equations are studied in the spaces.Bibliograpy has 70 items.U ovoj tezi su proučavani prostori temperiranih ultradistribucija Beurlingovog i Roumieovog tipa, koji su prirodna uopštenja prostora Schwarzovih temperiranih distribucija u Denjoy-Carleman-Komatsuovoj teoriji ultradistribucija. Dokazano je ovi prostori imaju sva dobra svojstva, koja ima i Schwarzov prostor, izmedju ostalog, značajno svojstvo da Furijeova transformacija preslikava te prostore neprekidno na same sebe.U prvom poglavlju su uvedene neophodne oznake i pojmovi.U drugom poglavlju su uvedeni prostori ultrabrzo opadajucih ultradiferencijabilnih funkcija i njihovi duali, prostori Beurlingovih i Rumieuovih temperiranih ultradistribucija; proučavana su njihova topološka svojstva i veze sa poznatim prostorima distribucija i ultradistribucija, kao i strukturne osobine; date su i karakterizacije Ermitskih ekspanzija i graničnih reprezentacija elemenata tih prostora.Prostori multiplikatora Beurlingovih i Roumieuovih temperiranih ultradistribucija su okarakterisani u trećem poglavlju.Četvrto poglavlje je posvećeno proučavanju Fourierove, Wignerove, Bargmanove i Hilbertove transformacije na prostorima Beurlingovih i Rouimieovih temperiranih ultradistribucija i njihovim test prostorima.U petoj glavi je dokazana ekvivalentnost klasičnih definicija konvolucije na Beurlingovim prostorima ultradistribucija, kao i ekvivalentnost novouvedenih definicija ultratemperirane konvolucije ultradistribucija Beurlingovog tipa.U poslednjoj glavi je dat potreban i dovoljan uslov da konvolutor prostora temperiranih ultradistribucija bude hipoeliptičan u prostoru integrabilnih ultradistribucija i razmatrane su neke konvolucione jednačine u tom prostoru.Bibliografija ima 70 bibliografskih jedinica.
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Ngounda, Edgard. "Efficient numerical methods based on integral transforms to solve option pricing problems." Thesis, University of the Western Cape, 2012. http://hdl.handle.net/11394/4223.
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Philosophiae Doctor - PhDIn this thesis, we design and implement a class of numerical methods (based on integral transforms) to solve PDEs for pricing a variety of financial derivatives. Our approach is based on spectral discretization of the spatial (asset) derivatives and the use of inverse Laplace transforms to solve the resulting problem in time. The conventional spectral methods are further modified by using piecewise high order rational interpolants on the Chebyshev mesh within each sub-domain with the boundary domain placed at the strike price where the discontinuity is located. The resulting system is then solved by applying Laplace transform method through deformation of a contour integral. Firstly, we use this approach to price plain vanilla options and then extend it to price options described by a jump-diffusion model, barrier options and the Heston’s volatility model. To approximate the integral part in the jump-diffusion model, we use the Gauss-Legendre quadrature method. Finally, we carry out extensive numerical simulations to value these options and associated Greeks (the measures of sensitivity). The results presented in this thesis demonstrate the spectral accuracy and efficiency of our approach, which can therefore be considered as an alternative approach to price these class of options.
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Pirbudak, Ozan. "Reconstruction of Radar Images by Using Spherical Mean and Regular Radon Transforms." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7889.
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The goal of this study is the recovery of functions and finite parametric distributions from their spherical means over spheres and designing a general formula or algorithm for the reconstruction of a function f via its spherical mean transform. The theoretical study is and supported with a numerical implementation based on radar data. In this study, we approach the reconstruction problem in two different way. The first one is to show how the reconstruction problem could be converted to a Prony-type system of equations. After solving this Prony-type system of equations, one can extract the parameters that describe the corresponding functions or distributions efficiently. The second way is to solve this problem via a backprojection procedure.
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Vasilieva, Olesya. "A new method of pricing multi-options using Mellin transforms and Integral equations." Thesis, Halmstad University, Applied Mathematics and Physics (CAMP), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-3075.
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In this thesis a new method for the option pricing will be introduced with
the help of the Mellin transforms. Firstly, the Mellin transform techniques for
options on a single underlying stock is presented. After that basket options
will be considered. Finally, an improvement of existing numerical results
applied to Mellin transforms for 1-basket and 2-basket American Put Option
will be discussed concisely. Our approach does not require either variable
transformations or solving diusion equations.
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Ambartsoumian, Gaik. "Spherical radon transforms and mathematical problems of thermoacoustic tomography." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1807.
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Roper, Ryan Todd. "A Study of Radiofrequency Cardiac Ablation Using Analytical and Numerical Techniques." Diss., CLICK HERE for online access, 2003. http://contentdm.lib.byu.edu/ETD/image/etd262.pdf.
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Pipkins, Daniel Scott. "Non-linear analysis of (i) wave propagation using transform methods and (ii) plates and shells using integral equations." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/20052.
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Fink, Thomas [Verfasser], Brigitte [Akademischer Betreuer] Forster-Heinlein, Uwe [Akademischer Betreuer] Kähler, and Daniel [Akademischer Betreuer] Potts. "Curvature Detection by Integral Transforms / Thomas Fink ; Brigitte Forster-Heinlein, Uwe Kähler, Daniel Potts." Passau : Universität Passau, 2020. http://d-nb.info/1203371632/34.
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Xu, Rui Hui. "Windowed linear canonical transform and its applications." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2493220.
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Skokan, Michal. "Regularity of ghosts of geodesic X-ray transform /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/5744.
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Krishnan, Venkateswaran P. "A support theorem and an inversion formula for the geodesic ray transform /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/5804.
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R?go, Maria das Gra?as Oliveira. "An?lise da magnetohidrodin?mica com transfer?ncia de calor em canais de placas paralelas via transforma??o integral." Universidade Federal do Rio Grande do Norte, 2010. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15631.
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Previous issue date: 2010-11-12Universidade Federal do Rio Grande do Norte
The main goal of the present work is related to the dynamics of the steady state, incompressible, laminar flow with heat transfer, of an electrically conducting and Newtonian fluid inside a flat parallel-plate channel under the action of an external and uniform magnetic field. For solution of the governing equations, written in the parabolic boundary layer and stream-function formulation, it was employed the hybrid, numericalanalytical, approach known as Generalized Integral Transform Technique (GITT). The flow is sustained by a pressure gradient and the magnetic field is applied in the direction normal to the flow and is assumed that normal magnetic field is kept uniform, remaining larger than any other fields generated in other directions. In order to evaluate the influence of the applied magnetic field on both entrance regions, thermal and hydrodynamic, for this forced convection problem, as well as for validating purposes of the adopted solution methodology, two kinds of channel entry conditions for the velocity field were used: an uniform and an non-MHD parabolic profile. On the other hand, for the thermal problem only an uniform temperature profile at the channel inlet was employed as boundary condition. Along the channel wall, plates are maintained at constant temperature, either equal to or different from each other. Results for the velocity and temperature fields as well as for the main related potentials are produced and compared, for validation purposes, to results reported on literature as function of the main dimensionless governing parameters as Reynolds and Hartman numbers, for typical situations. Finally, in order to illustrate the consistency of the integral transform method, convergence analyses are also effectuated and presented
O prop?sito do estudo desenvolvido nesse trabalho est? relacionado com a din?mica do escoamento incompress?vel, laminar, em regime permanente, com transfer?ncia de calor, de um fluido newtoniano condutor el?trico, no interior de um canal de placas planas paralelas, submetido a um campo magn?tico externo uniforme. Para a solu??o das equa??es de governo, modeladas atrav?s da formula??o parab?lica de camada limite em fun??o corrente, foi empregado o m?todo h?brido, num?rico-anal?tico, conhecido como T?cnica da Transformada Integral Generalizada (GITT). O escoamento analisado ? sustentando por um gradiente de press?o e assume-se que o campo magn?tico externo, aplicado na dire??o normal ao escoamento, permanece uniforme, muito maior do que quaisquer outros campos gerados em outras dire??es, n?o sendo, dessa forma, influenciado por nenhum efeito magn?tico interno. Para avaliar a influ?ncia do campo magn?tico sobre o desenvolvimento t?rmico e hidrodin?mico desse problema de convec??o for?ada, e tamb?m para fins de valida??o da metodologia de solu??o adotada, foram empregados dois tipos de condi??es de contorno para o campo de velocidade na entrada no canal: perfil uniforme e perfil parab?lico do escoamento sem campo magn?tico completamente desenvolvido. Para o problema t?rmico, por outro lado, empregou-se apenas o perfil uniforme de temperatura na entrada do canal e considerou-se que as placas se mant?m ? temperatura constante, iguais ou diferentes uma da outra. Resultados para os campos de velocidade, temperatura e potenciais correlatos s?o produzidos e comparados aos da literatura em fun??o dos principais par?metros de governo, a saber, n?mero de Reynolds, n?mero de Hartmann e par?metro el?trico, para algumas situa??es t?picas. Com o objetivo de ilustrar a consist?ncia da t?cnica da transformada integral generalizada, an?lises de converg?ncia s?o tamb?m efetuadas e apresentadas
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Goncharov, Fedor. "Transformations de Radon pondérées et leurs applications." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLX029/document.
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Cette thèse est consacrée à l'étude des problèmes inverses des transformations de Radon pondérées dans les espaces euclidiens. D'une part, nos études sont motivées par l'application des transformations de Radon pondérées pour différentes tomographies, par exemple en tomographie d'émission (PET, SPECT), en tomographie de fluorescence et en tomographie optique. En particulier, nous développons une nouvelle approche de reconstruction pour les tomographies en 3D, où les données sont modélisées par des transformations des rayons pondérées le long des rayons parallèles à un plan fixe. À cet égard, nos résultats contiennent : des formules pour la réduction des transformées des rayons pondérés en transformées de Radon le long de plans en 3D ; un analogue de la formule d'inversion approximative de Chang et un analogue de l'algorithme d'inversion itératif de type Kunyansky pour les transformations de Radon pondérées en multidimension ; des reconstructions numériques à partir de données simulées et réelles. D'autre part, nos études sont motivées par des problèmes mathématiques liés aux transformations susmentionnées. Plus précisément, nous poursuivons l'étude de l'injectivité et de la non-injectivité des transformations de Radon et des transformations des rayons pondérées en multidimension et construisons une série de contre-exemples à l'injectivité de ces dernières. Ces contre exemples sont intéressants et, dans un certain sens, inattendus parce qu'ils sont proches des cas où ces transformations deviennent injectives. En particulier, par l'une de nos constructions, nous donnons des contre-exemples à des théorèmes d'injectivité bien connus pour les transformations des rayons pondérées (Quinto (1983), Markoe, Quinto (1985), Finch (1986), Ilmavirta (2016)) lorsque les hypothèses de régularité des poids sont légèrement relaxées. Par ce résultat, nous montrons en particulier que les hypothèses de régularité sur les poids sont cruciales pour l'injectivité et qu'il y a une "brisure" de cette dernière si les hypothèses sont légèrement affaibliesThis thesis is devoted to studies of inverse problems for weighted Radon tranforms in euclidean spaces. On one hand, our studies are motivated by applications of weighted Radon transforms in different tomographies, for example, in emission tomographies (PET, SPECT), flourescence tomography and optical tomography. In particular, we develop a new reconstruction approach for tomographies in 3D, where data are modelized by weighted ray transforms along rays parallel to some fixed plane. In this connection our results include: formulas for reduction of the aforementioned weighted ray transforms to weghted Radon transforms along planes in 3D; an analog of Chang approximate inversion formula and an analog of Kunyansky-type iterative inversion algorithm for weighted Radon transforms in multidimensions; numercal reconstructions from simulated and real data. On the other hand, our studies are motivated by mathematical problems related to the aforementioned transforms. More precisely, we continue studies of injectivity and non-injectivity of weighted ray and Radon transforms in multidimensions and we construct a series of counterexamples to injectivity for the latter. These counterexamples are interesting and in some sense unexpected because they are close to the setting when the corresponding weighted ray and Radon transforms become injective. In particular, by one ofour constructions we give counterexamples to well-known injectivity theorems for weighted ray transforms (Quinto (1983), Markoe, Quinto (1985), Finch (1986), Ilmavirta (2016)) when the regularity assumptions on weights are slightly relaxed. By this result we show that, in particular, the regularity assumptions on weights are crucial for the injectivity and there is a breakdown of the latter if the assumptions are slightly relaxed
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Assad, Gustavo Elia. "Análise híbrida da interação mútua escoamento/campo magnético na região de entrada de um canal de placas paralelas." Universidade Federal da Paraíba, 2016. http://tede.biblioteca.ufpb.br:8080/handle/tede/8792.
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The aim of this work deals with the analysis of the mutual interaction between flow and magnetic fields that develops in a parallel-plate channel as soon as an external magnetic field is applied transversely to the plates. The fluid, electrically conductive, enters the channel under any velocity profile and will have its natural development within the channel changed by the applied magnetic field. With a coupled two-way interaction, the field will also be affected by the flow. The study of these interactions will be made from the two-dimensional version of the steady-state Navier-Stokes equations in the stream function formulation, coupled with the transport equation of the magnetic field. The solution of the governing equations will be obtained by the Generalized Integral Transform Technique (GITT). The results obtained for the velocity field, magnetic field and temperature field, as well as the associated scalar functions, are produced and compared with the literature on the basis of the main parameters of government: Reynolds number (Re), magnetic Reynolds number (Rem) and Hartmann number (Ha). In order to illustrate the consistency of the generalized integral transform technique, convergence analysis, are also performed and presented.
O objetivo do presente trabalho trata da análise da interação mútua escoamento/campo magnético que se desenvolve no interior de um canal de placas planas e paralelas ao se aplicar um campo magnético externo transversal. O fluido, eletricamente condutor, entra no canal sob um perfil qualquer de velocidade, e terá seu desenvolvimento natural afetado pelo campo magnético aplicado. Com uma interação acoplada de duas vias, o campo também será afetado pelo escoamento. O estudo dessas interações será efetuado a partir de uma formulação bidimensional das equações de Navier-Stokes, na formulação em função corrente, para escoamento em regime permanente, acoplada à equação de transporte do campo magnético. A solução das equações governantes será obtida através da Técnica da Transformada Integral Generalizada (GITT). Os resultados obtidos para o campo de velocidade e campo magnético, bem como suas funções escalares associadas, são produzidos e comparados aos da literatura em função dos principais parâmetros de governo: número de Reynolds (Re), número de Reynolds magnético (Rem) e número de Hartmann (Ha). Com o objetivo de ilustrar a consistência da técnica da transformada integral generalizada, análises de convergência são também efetuadas e apresentadas.
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Ячменьов, Володимир Олександрович, Владимир Александрович Ячменев, Volodymyr Oleksandrovych Yachmenov, and С. А. Терновский. "Решение начально-краевых задач для уравнений с дробными производными." Thesis, Сумский государственный университет, 2014. http://essuir.sumdu.edu.ua/handle/123456789/39366.
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Исследование диффузионных процессов аномальной природы, отклоняющихся от классической гауссовской диффузии, приводит к необходимости решения начально-краевых задач для дифференциальных уравнений с дробными производными.
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Gomes, Francisco Augusto Aparecido [UNESP]. "Estudo analítico/numérico do problema de ablação em corpos rombudos com simetria axial." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/88887.
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O fenômeno da ablação é um processo que envolve o estudo de proteções térmicas, com muitas aplicações, principalmente na engenharia mecânica e aeroespacial. O processo envolve transferência de calor com movimento de fronteira, onde a posição é desconhecida a priori. As equações governantes do processo formam um sistema não-linear de equações diferenciais acoplado. A análise unidimensional do processo ablativo é realizada em um corpo de revolução, o qual está sobre intenso aquecimento. Esse problema é resolvido utilizando a Técnica da Transformada Integral Generalizada – TTIG, para solução do sistema de equações governantes. Como condição de contorno é considerada um fluxo de calor transiente no contorno, como por exemplo, o que ocorre com veículos na reentrada da atmosfera. A teoria do fluxo de calor de Tauber e de Van Driest é utilizada nessa análise. Os resultados de interesse são, a espessura e a taxa de material ablatado. Os resultados obtidos são comparados com resultados disponíveis de outras técnicas de solução em literaturas.
The phenomenon of ablation is a process of thermal protection with several applications, mainly, in mechanical and aerospace engineering. This process involves heat transfer with a moving boundary which position is unknown a priori. The governing equations of the process are a non-linear system of coupled partial differential equations. The onedimensional analysis of ablative process has been done in a revolution body, which is on intense heating. This problem is performed by using the generalized integral transform technique – GITT for solution of the system of governing equations. As boundary condition is considered a transient heat flux like ones that occur, for example, in re-entrance of aerospace vehicles in the atmosphere. The heat flux theory of Tauber and Van Driest were used in that analysis. The results of interest are the thickness and the rate of loss of the ablative material. The obtained results are compared with available results of other techniques of solution in the literature.
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Chunaev, Petr. "Singular integral operators and rectifiability." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/663827.
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Los problemas que estudiamos en esta tesis se encuentran en el área de Análisis Armónico y Teoría de la Medida Geométrica. En particular, consideramos la conexión entre las propiedades analíticas de operadores integrales singulares definidos en $L^2(\mu)$ y asociados con algunos núcleos de Calderón-Zygmund y las propiedades geométricas de la medida $\mu$. Seamos más precisos.
Sea $E$ un conjunto de Borel en el plano complejo con la medida lineal de Hausdorff $H^1$ finita y distinta de cero, es decir, $0The problems that we study in this thesis lie in the area of Harmonic Analysis and Geometric Measure Theory. Namely, we consider the connection between the analytic properties of singular integral operators defined in $L^2(\mu)$ and associated with some Calderón-Zygmund kernels and the geometric properties of the measure $\mu$. Let us be more precise. Let $E$ be a Borel set in the complex plane with non-vanishing and finite linear Hausdorff measure $H^1$, i.e. such that $0
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Souza, Luís Henrique Gazeta de [UNESP]. "Aplicação da transformada integral generalizada no escoamento potencial em contrações." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/88871.
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souza_lhg_me_ilha.pdf: 1993240 bytes, checksum: b09e517d41877144e2a7b2634fd5fd55 (MD5)Realiza-se a formulação matemática do escoamento potencial no interior de contrações bidimensionais usando sistemas de coordenadas cartesianas e cilíndricas. Para tal considera-se que as geometrias das contrações sejam bidimensionais no sistema de coordenadas cartesianas e bidimensionais com simetria axial no sistema de coordenadas cilíndricas. A formulação é adaptada a partir das equações tridimensionais de Euler em coordenadas cartesianas e cilíndricas, fazendo-se as hipóteses de bidimensionalidade, regime permanente, fluido invíscido e escoamento irrotacional. O formalismo diferencial do escoamento potencial no interior de contrações bidimensionais é formalmente resolvido utilizando-se a Técnica da Transformada Integral Generalizada – TTIG – cuja fundamentação está na expansão de funções-quadrado-integráveis em séries de funções ortogonais. Desenvolveu-se algoritmos computacionais, em linguagem computacional Fortran 95, para simular as soluções formais obtidas e produzir resultados numéricos que possibilitassem a análise do escoamento potencial nas referidas contrações. Realizou-se extensivos testes numéricos para quatro famílias de geometrias das contrações, sendo que cada família ainda possuía diferentes funções modeladoras do formato de suas paredes, bem como os parâmetros razão e esbeltez e razão de contração. Analisou-se os resultados visando sintetizar aspectos e características de como as contrações operam e que formatos são mais adequados ou não
It was done the mathematical formulation for potential flow inside two-dimensional contractions using both Cartesian and cylindrical coordinate systems. To achieve such aim it was considered that contraction geometries are two-dimensional in the Cartesian coordinate system and two-dimensional with axial symmetry in cylindrical system. Formulation is adapted from tri-dimensional Euler equations in Cartesian and cylindrical coordinate systems, doing hypothesis such as: two-dimensionality, steady flow regime, inviscid fluid and irrotational flow. Differential formulae that models potential flow inside two-dimensional contraction is formally solved using Generalized Integral Transform Technique – GITT – which is based upon orthogonal series expansion of square-integrable functions. It was developed some computational algorithms, using Fortran 95 computational language, to simulate the obtained formal solutions and to produce numerical results that allows potential flow analysis for referred contractions. It was done comprehensive numerical tests for four families of contraction geometries, being that each family yet has different contraction wall modeling functions, as well length and contraction ratios. Results were analyzed aiming to synthesize aspects and characteristics of how contractions operate and which forms are more adequate or not
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Gomes, Francisco Augusto Aparecido. "Estudo analítico/numérico do problema de ablação em corpos rombudos com simetria axial /." Ilha Solteira : [s.n.], 2006. http://hdl.handle.net/11449/88887.
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Resumo: O fenômeno da ablação é um processo que envolve o estudo de proteções térmicas, com muitas aplicações, principalmente na engenharia mecânica e aeroespacial. O processo envolve transferência de calor com movimento de fronteira, onde a posição é desconhecida a priori. As equações governantes do processo formam um sistema não-linear de equações diferenciais acoplado. A análise unidimensional do processo ablativo é realizada em um corpo de revolução, o qual está sobre intenso aquecimento. Esse problema é resolvido utilizando a Técnica da Transformada Integral Generalizada - TTIG, para solução do sistema de equações governantes. Como condição de contorno é considerada um fluxo de calor transiente no contorno, como por exemplo, o que ocorre com veículos na reentrada da atmosfera. A teoria do fluxo de calor de Tauber e de Van Driest é utilizada nessa análise. Os resultados de interesse são, a espessura e a taxa de material ablatado. Os resultados obtidos são comparados com resultados disponíveis de outras técnicas de solução em literaturas.Abstract: The phenomenon of ablation is a process of thermal protection with several applications, mainly, in mechanical and aerospace engineering. This process involves heat transfer with a moving boundary which position is unknown a priori. The governing equations of the process are a non-linear system of coupled partial differential equations. The onedimensional analysis of ablative process has been done in a revolution body, which is on intense heating. This problem is performed by using the generalized integral transform technique - GITT for solution of the system of governing equations. As boundary condition is considered a transient heat flux like ones that occur, for example, in re-entrance of aerospace vehicles in the atmosphere. The heat flux theory of Tauber and Van Driest were used in that analysis. The results of interest are the thickness and the rate of loss of the ablative material. The obtained results are compared with available results of other techniques of solution in the literature.
Orientador: João Batista Campos Silva
Coorientador: Antonio João Diniz
Banca: Cássio Roberto Macedo Maia
Banca: Paulo Gilberto de Paula Toro
Mestre
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Souza, Luís Henrique Gazeta de. "Aplicação da transformada integral generalizada no escoamento potencial em contrações /." Ilha Solteira : [s.n.], 2009. http://hdl.handle.net/11449/88871.
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Orientador: João Batista AparecidoBanca: Cassio Roberto Macedo Maia
Banca: Alcides Padilha
Resumo: Realiza-se a formulação matemática do escoamento potencial no interior de contrações bidimensionais usando sistemas de coordenadas cartesianas e cilíndricas. Para tal considera-se que as geometrias das contrações sejam bidimensionais no sistema de coordenadas cartesianas e bidimensionais com simetria axial no sistema de coordenadas cilíndricas. A formulação é adaptada a partir das equações tridimensionais de Euler em coordenadas cartesianas e cilíndricas, fazendo-se as hipóteses de bidimensionalidade, regime permanente, fluido invíscido e escoamento irrotacional. O formalismo diferencial do escoamento potencial no interior de contrações bidimensionais é formalmente resolvido utilizando-se a Técnica da Transformada Integral Generalizada - TTIG - cuja fundamentação está na expansão de funções-quadrado-integráveis em séries de funções ortogonais. Desenvolveu-se algoritmos computacionais, em linguagem computacional Fortran 95, para simular as soluções formais obtidas e produzir resultados numéricos que possibilitassem a análise do escoamento potencial nas referidas contrações. Realizou-se extensivos testes numéricos para quatro famílias de geometrias das contrações, sendo que cada família ainda possuía diferentes funções modeladoras do formato de suas paredes, bem como os parâmetros razão e esbeltez e razão de contração. Analisou-se os resultados visando sintetizar aspectos e características de como as contrações operam e que formatos são mais adequados ou não
Abstract: It was done the mathematical formulation for potential flow inside two-dimensional contractions using both Cartesian and cylindrical coordinate systems. To achieve such aim it was considered that contraction geometries are two-dimensional in the Cartesian coordinate system and two-dimensional with axial symmetry in cylindrical system. Formulation is adapted from tri-dimensional Euler equations in Cartesian and cylindrical coordinate systems, doing hypothesis such as: two-dimensionality, steady flow regime, inviscid fluid and irrotational flow. Differential formulae that models potential flow inside two-dimensional contraction is formally solved using Generalized Integral Transform Technique - GITT - which is based upon orthogonal series expansion of square-integrable functions. It was developed some computational algorithms, using Fortran 95 computational language, to simulate the obtained formal solutions and to produce numerical results that allows potential flow analysis for referred contractions. It was done comprehensive numerical tests for four families of contraction geometries, being that each family yet has different contraction wall modeling functions, as well length and contraction ratios. Results were analyzed aiming to synthesize aspects and characteristics of how contractions operate and which forms are more adequate or not
Mestre
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Rastandi, Josia Irwan. "Modelization of dynamic soil-structure interaction using integral transform-finite element coupling." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=970018614.
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Chibawara, Trust. "Pricing and hedging asian options using Monte Carlo and integral transform techniques." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4292.
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Thesis (MSc (Mathematics))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: In this thesis, we discuss and apply the Monte Carlo and integral transform methods in pricing options. These methods have proved to be very e ective in the valuation of options especially when acceleration techniques are introduced. By rst pricing European call options we have motivated the use of these methods in pricing arithmetic Asian options which have proved to be di cult to price and hedge under the BlackScholes framework. The arithmetic average of the prices in this framework, is a sum of correlated lognormal distributions whose distribution does not admit a simple analytic expression. However, many approaches have been reported in the academic literature for pricing these options. We provide a hedging strategy by manipulating the results by Geman and Yor [42] for continuous xed strike arithmetic Asian call options. We then derive a double Laplace transform formula for pricing continuous Asian call options following the approach by Fu et al. [39]. By applying the multi-Laguerre and iterated Talbot inversion techniques for Laplace transforms to the resulting pricing formula we obtain the option prices. Finally, we discuss the shortcomings of using the Laplace transform in pricing options.
AFRIKAANSE OPSOMMING: In hierdie tesis bespreek ons Monte Carlo- en integraaltransform metodes om die pryse van nansi ele opsies te bepaal. Hierdie metodes is baie e ektief, veral wanneer versnellingsmetodes ingevoer word. Ons bepaal eers die pryse van Europese opsies as motivering, voordat ons die bostaande metodes gebruik vir prysbepaling van Asiatiese opsies met rekenkundige gemiddeldes, wat baie moeiliker is om te hanteer in die BlackScholes raamwerk. Die rekenkundige gemiddelde van batepryse in hierdie raamwerk is 'n som van gekorreleerde lognormale distribusies wie se distribusie nie oor 'n eenvoudige analitiese vorm beskik nie. Daar is egter talle benaderings vir die prysbepaling van hierdie opsies in die akademiese literatuur. Ons bied 'n verskansingsstrategie vir Asiatiese opsies in kontinue tyd met 'n vaste trefprys aan deur die resultate van Geman en Yor [42] te manipuleer. Daarna volg ons Fu et al. [39] om 'n dubbele Laplace transform formule vir die pryse af te lei. Deur toepassing van multi-Laguerre en herhaalde Talbotinversie tegnieke vir Laplace transforms op hierdie formule, bepaal ons dan die opsiepryse. Ons sluit af met 'n bespreking van die tekortkominge van die gebruik van die Laplace transform vir prysbepaling.
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Pavel, Dimovski. "Translation invariant Banach spaces of distributions and boundary values of integral transform." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2015. https://www.cris.uns.ac.rs/record.jsf?recordId=93767&source=NDLTD&language=en.
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We use common notation ∗ for distribution (Scshwartz), (Mp) (Beurling) i {Mp} (Roumieu) setting. We introduce and study new (ultra) distribution spaces, the test function spaces D∗E and their strong duals D'∗E’*.These spaces generalize the spaces D∗Lq , D'∗Lp , B’* and their weighted versions. The construction of our new (ultra)distribution spaces is based on the analysis of a suitable translation-invariant Banach space of (ultra)distribution E with continuous translation group, which turns out to be a convolution module over the Beurling algebra L1ω, where the weight ω is related to the translation operators on E. The Banach space E’∗ stands for L1ωˇ ∗ E’. We apply our results to the study of the convolution of ultradistributions. The spaces of convolutors O’∗C (Rn) for tempered ultradistributions are analyzed via the duality with respect to the test functionspaces O∗C (Rn), introduced in this thesis. Using the properties of translationinvariantBanach space of ultradistributions E we obtain a full characterization ofthe general convolution of Roumieu ultradistributions via the space of integrableultradistributions is obtained. We show: The convolution of two Roumieu ultradistributions T, S ∈ D’{Mp} (Rn) exists if and only if (φ ∗ Š) T ∈ D’{Mp}L1(Rn) for every φ ∈ D {Mp} (Rn). We study boundary values of holomorphic functions defined in tube domains. New edge of the wedge theorems are obtained. The resultsare then applied to represent D’E’* as a quotient space of holomorphic functions.We also give representations of elements of D’E’* via the heat kernel method.Koristimo oznaku ∗ za distribuciono (Svarcovo), (Mp) (Berlingovo) i {Mp} (Roumieuovo) okruženje. Uvodimo i prouavamo nove (ultra)distribucione prostore, test funkcijske prostore D∗E i njihove duale D'∗E'*. Ovi prostori uopštavaju prostore D∗Lq , D'∗Lp , B'∗ i njihove težinske verzije. Konstrukcija naših novih (ultra)distribucionih prostora je zasnovana na analizi odgovarajuićh translaciono - invarijantnih Banahovih prostora (ultra)distribucija koje označavamo sa E. Ovi prostori imaju neprekidnu grupu translacija, koja je konvolucioni modul nad Beurlingovom algebrom L1ω, gde je težina ω povezana sa operatorima translacije prostora E. Banahov prostor E'∗ označava prostor L1ω˅ ∗ E'. Koristeći dobijene rezultata proučavamo konvoluciju ultradistribucija. Prostori konvolutora O'∗C (Rn) temperiranih ultradistribucija, analizirani su pomoću dualnosti test funkcijskih prostora O∗C (Rn), definisanih u ovoj tezi. Koristeći svojstva translaciono - invarijantnih Banahovih prostora temperiranih ultradistribucija, opet označenih sa E, dobijamo karakterizaciju konvolucije Romuieu-ovih ultradistribucija, preko integrabilnih ultradistribucija. Dokazujemo da: konvolucija dve Roumieu-ove ultradistribucija T, S ∈ D'{Mp} (Rn) postoji ako i samo ako (φ ∗ Sˇ)T ∈ D'{Mp} L1 (Rn) za svaki φ ∈ D{Mp}(Rn). Takođe, proučavamo granične vrednosti holomorfnih funkcija definisanih na tubama. Dokazane su nove teoreme ”otrog klina”. Rezultati se zatim koriste za prezentaciju D'E'∗ preko faktor prostora holomorfnih funkcija. Takođe, data je prezentacija elemente D'E'∗ koristeći heat kernel metode.
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Huang, Min. "Applications of integral transform methods to the Schroedinger equation and dynamical systems." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1277345391.
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Vitturi, Marco. "Double Hilbert transforms along surfaces in the Heisenberg group." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/25418.
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We provide an L² theory for the local double Hilbert transform along an analytic surface (s, t ,φ(s, t )) in the Heisenberg group H¹, that is operator f ↦ Hφ f (x) := p.v.∫∣s∣,∣t∣≤1 f (x ∙ (s, t ,φ(s, t ))-¹) ds/s dt/t, where ∙ denotes the group operation in H1. This operator combines several features: it is amulti-parameter singular integral, its kernel is supported along a submanifold, and convolution is with respect to a homogeneous group structure. We reprove Hφ is always L²(H¹)→L²(H¹) bounded (a result first obtained in [Str12]) to illustrate the method and then refine it to characterize the largest class of polynomials P of degree less than d such that the operator HP is uniformly bounded when P ranges in the class. Finally, we provide examples of surfaces that can be treated by our method but not by the theory of [Str12].
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Alves, Thiago Antonini [UNESP]. "Aplicação da transformada integral e da transformação conforme na solução de uma classe de problemas difusivo-convectivos em domínios de geometrias não-convencionais." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/88876.
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alves_ta_me_ilha.pdf: 8112255 bytes, checksum: 408af7eb63e2a3050e7bda3fd133d8cf (MD5)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
O presente trabalho trata da solução de uma classe de problemas difusivo-convectivos, tanto de natureza elíptica como parabólica, em domínios de geometrias não-convencionais, através da aplicação da Transformada Integral. Para facilitar o tratamento analítico e a aplicação das condições de contorno, antes da aplicação da Técnica da Transformada Integral Generalizada - TTIG sobre a equação governante do problema estudado, emprega-se uma Transformação Conforme - TC visando efetuar uma mudança de coordenadas adequada. Analisa-se inicialmente o problema hidrodinâmico do escoamento laminar completamente desenvolvido de fluidos Newtonianos no interior de dutos. Para a obtenção do campo de velocidades do escoamento aplica-se a TTIG sobre a equação da quantidade de movimento. Os parâmetros hidrodinâmicos de interesse, tais como: velocidades média e máxima, fator de atrito de Fanning, fator de Hagenbach, número de Poiseuille, comprimento de entrada hidrodinâmico e queda de pressão são calculados para as diversas geometrias. Feito isso, efetua-se o estudo dos problemas difusivo-convectivos relacionados à transferência de calor do escoamento laminar hidrodinamicamente desenvolvido e termicamente em desenvolvimento de fluidos Newtonianos com perfil de temperatura de entrada uniforme em dutos submetidos a condições de contorno de Dirichlet. Para a obtenção do campo de temperatura aplica-se a TTIG sobre a equação da energia e então, calculam-se os parâmetros térmicos de interesse: temperatura média de mistura, números de Nusselt local e médio e comprimento de entrada térmica. Realiza-se, quando possível, a comparação dos resultados obtidos para os parâmetros termos-hidráulicos com os disponíveis na literatura.
The present work describes the solution of a class of elliptical-parabolic diffusiveconvective problems, on unconventional geometries, employing the Generalized Integral Transform Technique (GITT). In order to facilitate the analytical treatment and the application of the boundary conditions, a Conformal Transform (CT) is used to change the domain into a more suitable coordinate system, just before GITT is to be applied. First of all, using this procedure, the hydrodynamic problem of fully developed Newtonian laminar flow inside ducts is analyzed. In order to obtain the velocity field, GITT is applied on the momentum equation. Interesting hydrodynamic parameters, such as: maximum and minimum velocity values, Fanning friction and Hagenbach factors, Poiseuille number, hydrodynamic entry length, as well as pressure loss, are evaluated for several geometries. Following that, diffusive-convective problems are studied in relationship to the heat transfer in hydrodynamically fully developed and thermally non-developed Newtonian laminar flow inside ducts under Dirichlet boundary conditions, considering uniform temperature entrance profile. In order to obtain the temperature field, GITT is applied on the energy equation, evaluating the relevant parameters: bulk mean temperature, average and local Nusselt numbers and thermal entry length. The results are compared, as much as possible, with the parameter values available in the literature.
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Bacca, Sonia. "Study of electromagnetic reactions on light nuclei with the Lorentz integral transform method." [S.l. : s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976128365.
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Szabo, Szilard. "Nahm transform for integrable connections on the Riemann sphere." Université Louis Pasteur (Strasbourg) (1971-2008), 2005. http://www.theses.fr/2005STR13072.
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Ballard, Grey M. "Asymptotic behavior of the eigenvalues of Toeplitz integral operators associated with the Hankel transform." Electronic thesis, 2008. http://dspace.zsr.wfu.edu/jspui/handle/10339/221.
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Doroshenko, V. O., N. P. Klimova, N. P. Stognii, and Yu D. Kostyn. "Mathematical Modelling of Impulse Excitation of a Superwideband PEC Cone Antenna." Thesis, 2019 IEEE 8th International Conference on Advanced Optoelectronics and Lasers, CAOL*2019, 2019. https://openarchive.nure.ua/handle/document/16284.
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The method for solving initial-boundary electromagnetic problems is proposed. It uses the Green’s function method and the Laplace and Meler-Fock integral transforms in a time domain. The model problem of special slotted cone antenna excitation is studied. Integral and series representation of electromagnetic field component are given.
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Grouy, Thibaut. "Radon-type transforms on some symmetric spaces." Doctoral thesis, Universite Libre de Bruxelles, 2019. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/285815.
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Dans cette thèse, nous étudions des transformées de type Radon sur certains espaces symétriques. Une transformée de type Radon associe à toute fonction continue à support compact sur une variété $M$ ses intégrales sur une classe $Xi$ de sous-variétés de $M$. Le problème sur lequel nous nous concentrons est l'inversion d'une telle transformée, c'est-à-dire déterminer la fonction à partir de ses intégrales sur les sous-variétés dans $Xi$. Nous présentons d'abord la solution de ce problème inverse due à Sigurdur Helgason et François Rouvière, entre autres, lorsque $M$ est un espace symétrique riemannien isotrope et $Xi$ une certaine orbite de sous-variétés totalement géodésiques de $M$ sous l'action d'un groupe de transformations de Lie de $M$. La transformée de Radon associée est qualifiée de totalement géodésique.Sur les espaces symétriques pseudo-riemanniens semisimples, nous considérons une autre transformée de type Radon, qui associe à toute fonction continue à support compact ses intégrales orbitales, c'est-à-dire ses intégrales sur les orbites du sous-groupe d'isotropie du groupe des transvections. L'inversion des intégrales orbitales, qui est donnée par une formule-limite, a été obtenue par Sigurdur Helgason sur les espaces symétriques lorentziens à courbure sectionnelle constante et par Jeremy Orloff sur tout espace symétrique pseudo-riemannien semisimple de rang un. Nous résolvons le problème d'inversion des intégrales orbitales sur les espaces de Cahen-Wallach, qui sont les modèles d'espaces symétriques lorentziens indécomposables résolubles.Pour finir, nous nous intéressons aux transformées de type Radon sur les espaces symétriques symplectiques à courbure de type Ricci. L'inversion des orbitales intégrales sur ces espaces lorsqu'ils sont semisimples a déjà été obtenue par Jeremy Orloff. En revanche, lorsque ces espaces ne sont pas semisimples, la transformée donnée par les intégrales orbitales n’est pas inversible. Ensuite, nous déterminons les orbites de sous-variétés totalement géodésiques symplectiques ou lagrangiennes sous l'action d'un groupe de transformations de Lie de l'espace de départ. Dans ce contexte, la méthode d'inversion développée par Sigurdur Helgason et François Rouvière, entre autres, ne fonctionne que pour les transformées de Radon totalement géodésiques symplectiques sur les espaces symétriques kählériens à courbure holomorphe constante. Les formules d'inversion de ces transformées sur les espaces hyperboliques complexes sont dues à François Rouvière. Nous calculons les formules d'inversion de ces transformées sur les espaces projectifs complexes.In this thesis, we study Radon-type transforms on some symmetric spaces. A Radon-type transform associates to any compactly supported continuous function on a manifold $M$ its integrals over a class $Xi$ of submanifolds of $M$. The problem we address is the inversion of such a transform, that is determining the function in terms of its integrals over the submanifolds in $Xi$. We first present the solution to this inverse problem which is due to Sigurdur Helgason and François Rouvière, amongst others, when $M$ is an isotropic Riemannian symmetric space and $Xi$ a particular orbit of totally geodesic submanifolds of $M$ under the action of a Lie transformation group of $M$. The associated Radon transform is qualified as totally geodesic.On semisimple pseudo-Riemannian symmetric spaces, we consider an other Radon-type transform, which associates to any compactly supported continuous function its orbital integrals, that is its integrals over the orbits of the isotropy subgroup of the transvection group. The inversion of orbital integrals, which is given by a limit-formula, has been obtained by Sigurdur Helgason on Lorentzian symmetric spaces with constant sectional curvature and by Jeremy Orloff on any rank-one semisimple pseudo-Riemannian symmetric space. We solve the inverse problem for orbital integrals on Cahen-Wallach spaces, which are model spaces of solvable indecomposable Lorentzian symmetric spaces.In the last part of the thesis, we are interested in Radon-type transforms on symplectic symmetric spaces with Ricci-type curvature. The inversion of orbital integrals on these spaces when they are semisimple has already been obtained by Jeremy Orloff. However, when these spaces are not semisimple, the orbital integral operator is not invertible. Next, we determine the orbits of symplectic or Lagrangian totally geodesic submanifolds under the action of a Lie transformation group of the starting space. In this context, the technique of inversion that has been developed by Sigurdur Helgason and François Rouvière, amongst others, only works for symplectic totally geodesic Radon transforms on Kählerian symmetric spaces with constant holomorphic curvature. The inversion formulas for these transforms on complex hyperbolic spaces are due to François Rouvière. We compute the inversion formulas for these transforms on complex projective spaces.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Butler, Samuel Thomas James. "Inverse Scattering Transform Method for Lattice Equations." Thesis, The University of Sydney, 2012. http://hdl.handle.net/2123/8724.
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The main original contribution of this thesis is the development of a fully discrete inverse scattering transform (IST) method for nonlinear partial difference equations. The equations we solve are nonlinear partial difference equations on a quad-graph, also called lattice equations, which are known to be multidimensionally consistent in N dimensions for arbitrary N. Such equations were discovered by Nijhoff, Quispel and Capel and Adler and later classified by Adler, Bobenko and Suris. The main equation solved by our IST framework is the Q3δ lattice equation. Our approach also solves all of its limiting cases, including H1, known as the lattice potential KdV equation. Our results provide the discrete analogue of the solution of the initial value problem on the real line. We provide a rigorous justification that solves the problem for wide classes of initial data given along initial paths in a multidimensional lattice. Moreover, we show how soliton solutions arise from the IST method and also utilise asymptotics of the eigenfunctions to construct infinitely many conservation laws.
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Poliak, Juraj. "Vliv optických prvků na vyzařovaný laserový svazek." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219107.
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Diplomová práca pojednáva o skalárnej teórii difrakcie a zavádza dôležité riešenie vlnovej rovnice a to elipticky symetrický Gaussov zväzok. V praktickej časti bude popísané modelovanie difrakcie na kruhovom otvore dvoma rôznymi prístupmi. Model bude experimentálne overený experimentom. V záverečnej časti bude kriticky pojednané o výsledkoch experimentu a simulácie.
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Aquino, Junielson Pantoja de. "Alguns resultados sobre a teoria de restrição da transformada de Fourier." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/159583.
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A análise harmônica e o ramo da matemática que estuda a representação de funções ou sinais como a sobreposição de ondas base. Ela investiga e generaliza as noções das séries de Fourier e da transformação de Fourier. Neste trabalho, investigou-se um teorema de restrição da transformada de Fourier devido a Mitsis e Mockenhaupt (uma generalização do teorema de Stein-Tomas). Foram realizados estudos analíticos sobre o método para operadores integrais oscilatórios, baseado na fase estacionária. Os resultados permitem deduzir o teorema de restrição no plano (em seu caso geral) e o teorema de Carleson-Sjölin.Harmonic analysis is the mathematical branch that studies the function or signals representation as a base wave overlay. It investigates and generalizes the notions of Fourier series and of the Fourier transform. In this work, was investigated a restriction theorem of the Fourier transform due to Mitsis and Mockenhaupt (a generalization of Stein-Tomas theorem) . Were performed analytic studies on the method for oscillating integral operators, based in the stationary phase. The results allow deducing the restriction theorem on the plane (in the general case) and the Carleson-Sjölin theorem.
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Bishop, Shannon Renee Smith. "Gabor and wavelet analysis with applications to Schatten class integral operators." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33976.
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This thesis addresses four topics in the area of applied harmonic analysis. First, we show that the affine densities of separable wavelet frames affect the frame properties. In particular, we describe a new relationship between the affine densities, frame bounds and weighted admissibility constants of the mother wavelets of pairs of separable wavelet frames. This result is also extended to wavelet frame sequences. Second, we consider affine pseudodifferential operators, generalizations of pseudodifferential operators that model wideband wireless communication channels. We find two classes of Banach spaces, characterized by wavelet and ridgelet transforms, so that inclusion of the kernel and symbol in appropriate spaces ensures the operator is Schatten p-class. Third, we examine the Schatten class properties of pseudodifferential operators. Using Gabor frame techniques, we show that if the kernel of a pseudodifferential operator lies in a particular mixed modulation space, then the operator is Schatten p-class. This result improves existing theorems and is sharp in the sense that larger mixed modulation spaces yield operators that are not Schatten class. The implications of this result for the Kohn-Nirenberg symbol of a pseudodifferential operator are also described. Lastly, Fourier integral operators are analyzed with Gabor frame techniques. We show that, given a certain smoothness in the phase function of a Fourier integral operator, the inclusion of the symbol in appropriate mixed modulation spaces is sufficient to guarantee that the operator is Schatten p-class.
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Gismalla, Yousif Ebtihal. "Performance analysis of spectrum sensing techniques for cognitive radio systems." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/performance-analysis-of-spectrum-sensing-techniques-for-cognitive-radio-systems(157fe1af-717c-4705-a649-d809766cf5cb).html.
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Cognitive radio is a technology that aims to maximize the current usage of the licensed frequency spectrum. Cognitive radio aims to provide services for license-exempt users by making use of dynamic spectrum access (DSA) and opportunistic spectrum sharing strategies (OSS). Cognitive radios are defined as intelligent wireless devices capable of adapting their communication parameters in order to operate within underutilized bands while avoiding causing interference to licensed users. An underused band of frequencies in a specific location or time is known as a spectrum hole. Therefore, in order to locate spectrum holes, reliable spectrum sensing algorithms are crucial to facilitate the evolution of cognitive radio networks. Since a large and growing body of literature has mainly focused into the conventional time domain (TD) energy detector, throughout this thesis the problem of spectrum sensing is investigated within the context of a frequency domain (FD) approach. The purpose of this study is to investigate detection based on methods of nonparametric power spectrum estimation. The considered methods are the periodogram, Bartlett's method, Welch overlapped segments averaging (WOSA) and the Multitaper estimator (MTE). Another major motivation is that the MTE is strongly recommended for the application of cognitive radios. This study aims to derive the detector performance measures for each case. Another aim is to investigate and highlight the main differences between the TD and the FD approaches. The performance is addressed for independent and identically distributed (i.i.d.) Rayleigh channels and the general Rician and Nakagami fading channels. For each of the investigated detectors, the analytical models are obtained by studying the characteristics of the Hermitian quadratic form representation of the decision statistic and the matrix of the Hermitian form is identified. The results of the study have revealed the high accuracy of the derived mathematical models. Moreover, it is found that the TD detector differs from the FD detector in a number of aspects. One principal and generalized conclusion is that all the investigated FD methods provide a reduced probability of false alarm when compared with the TD detector. Also, for the case of periodogram, the probability of sensing errors is independent of the length of observations, whereas in time domain the probability of false alarm is increased when the sample size increases. The probability of false alarm is further reduced when diversity reception is employed. Furthermore, compared to the periodogram, both Bartlett method and Welch method provide better performance in terms of lower probability of false alarm but an increased probability of detection for a given probability of false alarm. Also, the performance of both Bartlett's method and WOSA is sensitive to the number of segments, whereas WOSA is also sensitive to the overlapping factor. Finally, the performance of the MTE is dependent on the number of employed discrete prolate spheroidal (Slepian) sequences, and the MTE outperforms the periodogram, Bartlett's method and WOSA, as it provides the minimal probability of false alarm.
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Moghaddam, Peyman P., and Felix J. Herrmann. "Migration preconditioning with curvelets." Society of Exploration Geophysicists, 2004. http://hdl.handle.net/2429/425.
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In this paper, the property of Curvelet transforms for preconditioning the migration and normal operators is investigated. These operators belong to the class of Fourier integral operators and pseudo-differential operators, respectively. The effect of this preconditioner is shown in term of improvement of sparsity, convergence rate, number of iteration for the Krylov-subspace solver and clustering of singular(eigen) values. The migration operator, which we employed in this work is the common-offset Kirchoff-Born migration.
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Almeida, Luis Miguel Lima de. "All-optical processing based on integrated optics." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13705.
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Mestrado em Engenharia Eletrónica e TelecomunicaçõesDuring the last years, the demand for high data transfer rates in optical fiber communications has increased exponentially. Since image in its original format exactly as it is captured by the digital camera requires an enormous amount of storage capacity, it is important to develop a system that increases its amount of compression while preserving the important image’s information. In the topic of image’s compression, there are several transformation techniques used for data compression. Discrete Wavelet Transform (DWT) is one of the most commonly used, thanks to its multi-resolution transformation. This multi-resolution property allows to develop, not only a lossless compression method, from which the original image can be obtained exactly as it was before the transform, but also, a lossy method where it is not possible to obtain the original image. In this context, this thesis will develop the idea to apply the Haar wavelet transform using optical circuits. This concept will be analyzed, verifying the possibility of its implementation in the optical domain, using several methods, lossy and lossless, to conclude about the best compression method to apply to an image. Finally, the lossy method will be tested in the laboratory with different components and design the optical device able to accomplish the Haar wavelet transform.
Nos últimos anos, a procura por elevados ritmos de transferência de informação em comunicações óticas tem aumentado exponencialmente. Dado que imagem, no seu formato original exactamente como é captada pela câmara fotográfica ocupa enormes quantidades de espaço de armazenamento, torna-se importante desenvolver um sistema que aumente o seu grau de compressão, preservando as informações importantes da imagem. No tópico da compressão de imagem existem várias técnicas de transformação usadas para compressão de dados. A transformada discreta de onduleta é uma das mais usadas, graças ao uso da transformação em multiresolução. Esta propriedade de multi-resolução permite não só desenvolver métodos de compressão de imagem sem perdas, nos quais se obtém a imagem original exatamente como era antes da transformação, como também métodos com perdas, já não sendo possível obter a imagem original. Neste contexto, esta tese irá desenvolver a ideia de aplicar a transformada de onduleta de Haar usando circuitos óticos. Este conceito irá ser analisado, verificando a possibilidade da sua implementação no domínio ótico, usando vários métodos, com perdas e sem perdas, para concluir acerca do melhor método de compressão a aplicar a uma imagem. Por fim, o método com perdas irá ser testado no laboratório com diferentes componentes e desenhar o dispositivo ótico capaz de aplicar a transformada de onduleta de Haar.
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Camargo, Rubens de Figueiredo. "Calculo fracionario e aplicações." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/307012.
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Orientadores: Edmundo Capelas de Oliveira, Ary Orozimbo ChiacchioTese (doutorado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica
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Resumo: Apresentamos neste trabalho um estudo sistemático e detalhado sobre integrais e derivadas de ordens arbitrárias, o assim chamado cálculo de ordem não-inteira, popularizado com o nome de Cálculo Fracionário. Em particular, discutimos e resolvemos equações diferenciais e integrodiferenciais de ordem não-inteira e suas aplicações em diversas áreas do conhecimento, bem como apresentamos resultados inéditos, isto é, teoremas de adição, envolvendo as funções de Mittag-Leffler. Após abordar as diferentes definições para a derivada de ordem não-inteira, justificamos o fato de utilizarmos, em nossas aplicações, a definição de derivada conforme proposta por Caputo, mais restritiva, e não a definição segundo Riemann-Liouville, embora seja esta a mais difundida. Nas aplicações apresentamos uma generalização para a equação diferencial associada ao problema do telégrafo na versão fracionária, cuja solução, obtida de duas maneiras distintas, deu origem a dois novos teoremas de adição envolvendo as funções de Mittag-Leffler. Numa segunda aplicação, discutimos o conhecido sistema de Lotka-Volterra na versão fracionária; por fim, introduzimos e resolvemos uma equação integrodiferencial fracionária, a assim chamada, equação de Langevin generalizada fracionária.
Abstract: At this work we present a systematic and detailed study about integrals and derivatives of arbitrary order, the so-called non-integer order calculus, popularized with the name Fractional Calculus. Particularly, we discuss and solve non-integer order differential and integrodifferential equations and its applications into several areas of the knowledge, as well as introduce some new results, i.e., addition theorems, involving the Mittag-Leffler functions. After approaching the different definitions to the non-integer order derivative, we justify the fact that we use, in our applications, the definition proposed by Caputo to the fractional derivative, which is more restrictive, instead of the Riemann-Liouville ones, although this one is best known. Into the applications we presented a fractional generalization to the equation associated with the telegraph's problem, whose solution, obtained by two different ways, was the origin of two new addition theorems to the Mittag-Leffler functions. As a second application, we present the fractional version of the Lotka-Volterra system; finally, we introduce and solve the fractional generalized Langevin equation.
Doutorado
Doutor em Matemática
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Li, Wei. "Thermal Barrier Effect, Non-Fourier Effect and Inertia Effect on a Cracked Plate under Thermal Shock Loading." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCD089/document.
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Les chocs thermiques provoquent, en général, l’endommagement et la fissuration des matériaux. Ces phénomènes sont observés, par exemple, dans le revêtement de barrière thermique pour les moteurs des turbines, le traitement des surfaces ou la soudure par laser etc. Plusieurs travaux de recherche ont été réalisés au cours des dernières décennies dans l’objectif d’améliorer les performances thermiques et/ou mécaniques des matériaux sous chargement thermique. L’étude des dommages et de la fissuration des matériaux provoqués par les chocs thermiques, tels que le décollement des interfaces et de décohésion de revêtements, a reçu également une attention considérable par les chercheurs. La majorité de ces travaux utilisent les théories classiques, tels que la loi de Fourier de conduction thermique et l'hypothèse de quasi-statique. Malheureusement ces théories ne sont pas adaptées dans le cas de charges extrêmes provoqués par le choc thermique et dans le cas des matériaux micro-fissurés. En conséquence, les théories conventionnelles doivent être enrichies.L'objectif de la thèse est de montrer le rôle crucial des termes non Fourier et les termes inertiels dans le cas de choc thermique sous conditions sévères et dans le cas où les fissures sont petites. Pour cela nous avons mené des études sur deux structures particulières soumises à des chocs thermiques. Chaque structure contient une fissure parallèle au bord libre de la structure située au voisinage de ce dernier. L’influence de la présence de fissure sur la conductivité thermique est prise en compte. Nous avons utilisé la théorie Hyperbolique de transfert de chaleur par conduction pour les champs thermique et mécanique à la place de la théorie traditionnelle classique de Fourier. Pour mener cette étude, nous avons utilisé les Transformées de Laplace et de Fourier aux équations de mouvement et à l’équation de transfert de chaleur. En s’intéressant en particulier aux champs de contrainte au voisinage de la pointe de fissure et aux facteurs d'intensité de contrainte dynamiques. Le problème se ramène à la résolution d’un système d'équations intégrales singulières dans l'espace de Laplace-Fourier. On utilise une méthode d'intégration numérique pour obtenir les différents champs. Nous résolvons ensuite un système d'équations algébriques linéaires. En effectuant des inversions numériques des transformées, nous obtenons les champs de contrainte de température et les facteurs d'intensité de contrainte dynamiques dans le domaine temporel.Les résultats numériques montrent que la conductivité thermique du milieu est affectée par l’ouverture de la fissure ce qui perturberait fortement le champ de température ainsi que l'amplitude des facteurs d'intensité de contrainte dynamiques. Les amplitudes sont supérieures à celles obtenues à partir de la théorie classique de Fourier ainsi que dans le cadre de l'hypothèse quasi-statique. On constate également qu’elles oscillent au cours du temps. La prise en compte simultanément de l’influence de la fissure sur la conductivité thermique, de l'effet non-Fourier ainsi que les effetsIVd'inertie induit un couplage entre les trois phénomènes qui rendrait le problème de choc thermique très complexe. L'effet de barrière thermique induit par la fissure affecte d’une manière significative les champs de température et des contraintes. Les effets d’inertie, et des termes non-Fourier joueraient également un rôle non négligeable lorsque la longueur de la fissure est petite. Comme dans de nombreux problèmes d'ingénierie, l'initiation et la propagation des micro-fissures sont des mécanismes dont il faut tenir compte dans les prévisions de la rupture des structures. Ces effets non conventionnels ne sont plus négligeables et doivent être inclus dans l'analyse de la fracture des structures soumises à des chocs thermiquesThermal shock problems occur in many engineering materials and elements, which are used in high temperature applications such as thermal barrier coatings (TBCs), solid propellant of rocket-engine, pulsed-laser processing of materials, and so on. The thermal shock resistance performances and the thermal shock damages of materials, especially the interface debonding and spallation of coatings, have received considerable attention in both analysis and design. Some conventional theories, such as the Fourier’s law of thermal conduction and the quasi-static assumption of the thermoelastic body, may no longer be appropriate because of the extreme loads provoked by the thermal shock. Therefore, these conventional theories need to be enriched or revised.The objective of this thesis is to develop the solutions of the transient temperature field and thermal stresses around a partially insulated crack in a thermoelastic strip under thermal shock loading. The crack lies parallel to the heated traction free surface. The thermal conductivity of the crack gap is taken into account. Hyperbolic heat conduction theory is used in solving the temperature field instead of the traditional Fourier thermal conduction theory. Equations of motion are applied to obtain the stress fields and the dynamic stress intensity factors of the crack. The Laplace and Fourier transforms are applied to solve the thermal-elastic governing equations such that the mixed boundary value problems are reduced to solving a singular integral equations system in Laplace-Fourier space. The numerical integration method is applied to get the temperature field and stress fields, respectively. The problems are then solved numerically by converting the singular integral equations to a linear algebraic equations system. Finally, numerical inversions of the Laplace transform are performed to obtain the temperature field and dynamic stress intensity factors in the time domain.Numerical results show that the thermal conductivity of the crack gap strongly affects the uniformity of the temperature field and consequently, the magnitude of the dynamic stress intensity factors of the crack. The stress intensity factors would have higher amplitude and oscillating feature comparing to those obtained under the conventional Fourier thermal conduction and quasi-static hypotheses. It is also observed that the interactions of the thermal conductivity of the crack gap, the non-Fourier effect and the inertia effects would make the dynamic thermal shock problem more complex. The magnitude of the thermal barrier, non-Fourier and inertia effects is estimated for some practical cases
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Alves, Thiago Antonini. "Aplicação da transformada integral e da transformação conforme na solução de uma classe de problemas difusivo-convectivos em domínios de geometrias não-convencionais /." Ilha Solteira : [s.n.], 2006. http://hdl.handle.net/11449/88876.
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Resumo: O presente trabalho trata da solução de uma classe de problemas difusivo-convectivos, tanto de natureza elíptica como parabólica, em domínios de geometrias não-convencionais, através da aplicação da Transformada Integral. Para facilitar o tratamento analítico e a aplicação das condições de contorno, antes da aplicação da Técnica da Transformada Integral Generalizada - TTIG sobre a equação governante do problema estudado, emprega-se uma Transformação Conforme - TC visando efetuar uma mudança de coordenadas adequada. Analisa-se inicialmente o problema hidrodinâmico do escoamento laminar completamente desenvolvido de fluidos Newtonianos no interior de dutos. Para a obtenção do campo de velocidades do escoamento aplica-se a TTIG sobre a equação da quantidade de movimento. Os parâmetros hidrodinâmicos de interesse, tais como: velocidades média e máxima, fator de atrito de Fanning, fator de Hagenbach, número de Poiseuille, comprimento de entrada hidrodinâmico e queda de pressão são calculados para as diversas geometrias. Feito isso, efetua-se o estudo dos problemas difusivo-convectivos relacionados à transferência de calor do escoamento laminar hidrodinamicamente desenvolvido e termicamente em desenvolvimento de fluidos Newtonianos com perfil de temperatura de entrada uniforme em dutos submetidos a condições de contorno de Dirichlet. Para a obtenção do campo de temperatura aplica-se a TTIG sobre a equação da energia e então, calculam-se os parâmetros térmicos de interesse: temperatura média de mistura, números de Nusselt local e médio e comprimento de entrada térmica. Realiza-se, quando possível, a comparação dos resultados obtidos para os parâmetros termos-hidráulicos com os disponíveis na literatura.Abstract: The present work describes the solution of a class of elliptical-parabolic diffusiveconvective problems, on unconventional geometries, employing the Generalized Integral Transform Technique (GITT). In order to facilitate the analytical treatment and the application of the boundary conditions, a Conformal Transform (CT) is used to change the domain into a more suitable coordinate system, just before GITT is to be applied. First of all, using this procedure, the hydrodynamic problem of fully developed Newtonian laminar flow inside ducts is analyzed. In order to obtain the velocity field, GITT is applied on the momentum equation. Interesting hydrodynamic parameters, such as: maximum and minimum velocity values, Fanning friction and Hagenbach factors, Poiseuille number, hydrodynamic entry length, as well as pressure loss, are evaluated for several geometries. Following that, diffusive-convective problems are studied in relationship to the heat transfer in hydrodynamically fully developed and thermally non-developed Newtonian laminar flow inside ducts under Dirichlet boundary conditions, considering uniform temperature entrance profile. In order to obtain the temperature field, GITT is applied on the energy equation, evaluating the relevant parameters: bulk mean temperature, average and local Nusselt numbers and thermal entry length. The results are compared, as much as possible, with the parameter values available in the literature.
Orientador: Cassio Roberto Macedo Maia
Coorientador: Ricardo Alan Verdú Ramos
Banca: João Batista Campos Silva
Banca: Marcelo Moreira Ganzarolli
Mestre
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Bastos, ?sis Boll de Ara?jo. "A efetividade da previs?o constitucional de prote??o integral de crian?as e adolescentes : o uso da media??o como procedimento adequado ? transforma??o dos conflitos conjuparentais." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2018. http://tede2.pucrs.br/tede2/handle/tede/8278.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
The effectiveness of the constitutional provision of integral protection of children and adolescents with the use of mediation as a proper procedure in the transformation of conjugalparental disputes is the theme to be here developed. The general objective is to analyze the procedural adequation of mediation as a means of transformation of conjugal-parental conflicts with juridical effects. The specific objectives have been unfolded in identifying the conceptual content of integral protection and verifying the suitable procedural construction of mediation by considering the Child and Youth Law. The central issue involves assessing whether mediation is a suitable means to actualize and materialize the integral protection of children and adolescents, as well as the procedures required to achieve this goal. It is understood that, in the face of a specific and associated procedural commitment of mediation of conflicts, by means of collaborative and committed behaviors of integral protection agents (family, society and State), the materialization of the integral protection is a real possibility in the sphere of mediation. By following three sequential paths, the procedure is suitable to attain the intended result. The first one is the moment of pre-judicial mediation, i.e. before any judicial or litigation proceeding. The second one is the action of society, in the person of both the mediator, on the grounds of their training and accountability, and the lawyer, through their collaborative and committed action. The third one is the function of the State as an agent of planning and taking actions intended for increasing and providing judicial and managerial settings for implementation of mediation. Thus, if the previous procedural sequence is followed, mediation becomes a proper procedure for transformation of conjugal-parental disputes, and it materializes the integral protection of children and adolescents.
A efetividade da previs?o constitucional de prote??o integral de crian?as e adolescentes a partir do uso da media??o como procedimento adequado ? transforma??o dos conflitos conjuparentais ? o tema a ser desenvolvido. O objetivo geral ? analisar a aptid?o procedimental da media??o como meio de transforma??o de conflitos conjuparentais com reflexos jur?dicos. Os objetivos espec?ficos desdobram-se em identificar o conte?do conceitual de prote??o integral e verificar a constru??o procedimental adequada da media??o a partir do Direito da Crian?a e do Adolescente. A problem?tica central implica aferir se a media??o ? um meio adequado para efetivar e concretizar a prote??o integral de crian?as e adolescentes e o que precisa ser realizado em termos procedimentais para atingir este fim. Entende-se que, diante de um comprometimento procedimental espec?fico e vinculado da media??o de conflitos, mediante comportamentos colaborativos e comprometidos dos agentes de prote??o integral (fam?lia, sociedade e Estado), o resultado de concretiza??o da prote??o integral ? uma possibilidade real no ?mbito da media??o. O procedimento, ao obedecer a tr?s caminhos sequenciais, ? apto a atingir o resultado pretendido. O primeiro ? o momento de ocorr?ncia da media??o de forma pr?-judicial, antes de qualquer procedimento judicial ou processual. O segundo ? a a??o da sociedade, nas figuras do mediador, a partir dos pilares da capacita??o e responsabiliza??o, e do advogado, por meio de uma atua??o colaborativa e comprometida. O terceiro ? a fun??o do Estado como ator de planejamento e a??es direcionadas ? amplia??o e facilita??o de espa?os administrativos e judiciais para implementa??o da media??o. Logo, a media??o, observada a sequ?ncia procedimental exposta, ? procedimento adequado ? transforma??o dos conflitos conjuparentais e concretiza a prote??o integral de crian?as e adolescentes.
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Vasconcellos, Vagner. "Proposição de um sistema integrado de gestão de transformadores." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-13082007-154218/.
Full textAbstract:
O transformador de potência é o ativo mais valioso e importante de uma subestação, razão pela qual se faz necessário um acompanhamento especial para estes equipamentos. A operação de qualquer equipamento fora de suas condições nominais é sempre uma situação de risco, porém, tal risco pode ser minimizado através de estudos e análises particulares para cada equipamento.Com os transformadores de potência isso não é diferente, as normas e guias de aplicação de cargas em transformadores prevêem períodos de sobrecarga dentro de algumas condições, porém, há uma grande incerteza nesses dados já que cada transformador envelhece de forma diferente ainda que sejam idênticos de projeto e fabricação. Por essa razão se faz necessária uma análise particular de cada equipamento onde serão identificados os riscos em potencial e a partir daí determinado o grau de confiabilidade do equipamento. Com base em informações históricas dos equipamentos e algoritmos desenvolvidos com base nas normas vigentes, foi desenvolvido o Sistema Integrado de Gestão denominado SGT. Através deste sistema será possível armazenar de forma organizada as informações de todas as unidades fornecendo subsídios para uma tomada de decisão minimizando os riscos. Através do Sistema Integrado será possível estabelecer uma base única de consultas, promovendo assim a otimização destes equipamentos face a regulação do setor elétrico.The power transformer is the most valuable and important assets of a substation, for that reason is necessary a special attendance for these equipments. The operation of any equipment out of their nominal conditions it is always a risk situation, however, such a risk can be minimized through studies and private analyses for each equipment. Power transformers are not different, the norms and guides of load application foresee overload periods under some conditions, however, and there is a great uncertainty in those data since each transformer ages in a different way although they are identical of project and production. For that reason are necessary peculiar analysis of each equipment where you/they will be identified the potential risks and since then certain the degree of reliability of the equipment. Based in historical informations of the equipments and algorithms developed in agreement with the effective norms, the Integrated System of Management was developed and denominated SGT. Through this system it will be possible to store in an organized way the information of all of the units, supplying subsidies to have a safe decision minimizing the risks. Through the Integrated System it will be possible to establish an only base of consultations, promoting the assets optimization based in the new regulation of the electric section.