Tesi: "Nodal" – Grafiati

1

Georgiev, Bogdan [Verfasser]. "On the geometry of nodal sets and nodal domains / Bogdan Georgiev". Bonn : Universitäts- und Landesbibliothek Bonn, 2018. http://d-nb.info/117378960X/34.

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2

Davies, Brian E., Graham M. L. Gladwell, Josef Leydold e Peter F. Stadler. "Discrete Nodal Domain Theorems". Department of Statistics and Mathematics, Abt. f. Angewandte Statistik u. Datenverarbeitung, WU Vienna University of Economics and Business, 2000. http://epub.wu.ac.at/976/1/document.pdf.

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3

Davies, Brian E., Josef Leydold e Peter F. Stadler. "Discrete Nodal Domain Theorems". Department of Statistics and Mathematics, Abt. f. Angewandte Statistik u. Datenverarbeitung, WU Vienna University of Economics and Business, 2000. http://epub.wu.ac.at/1674/1/document.pdf.

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4

Stålhammar, Marcus. "Knotted Nodal Band Structures". Licentiate thesis, Stockholms universitet, Fysikum, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-176063.

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It is well known that in conventional three dimensional (3D) Hermitian two band models, the intersections between the energy bands are generically given by points. The typical example are Weyl semimetals, where these singular points can be effectively described as Weyl fermions in the low energy regime. By explicitly imposing discrete symmetries or fine-tuning, the intersection can form higher- dimensional nodal structures, e.g. nodal lines. By instead considering dissipative contributions to such a system, the degeneracies will generically take the form of closed 1D curves, consisting of exceptional points, i.e. points where the Hamiltonian becomes defective. By constructing the Hamiltonian in a particular way, the 1D exceptional curves can host non-trivial topology, i.e. they can form links or knots in the Brillouin zone. In stark contrast to line nodes occurring in Hermitian systems, which inevitably rely on discrete symmetries or fine tuning, the exceptional knots are generically stable towards any small perturbation. In further contrast to point singularities and unknotted circles, the topology of knots cannot be characterized by usual integer valued invariants. Instead, the complexity of the knottedness is captured by polynomial type invariants, making the physical classification and interpretation of these system challenging. To this end, the study of knotted nodal band structures naturally brings two different aspects of topology together – mathematical knot theory on the one hand, and the physical theory of topological phases on the other hand. This licentiate thesis focuses on providing the necessary theoretical background to understand the two accompanying publications entitled Knotted non-Hermitian metals, written by Johan Carlström, together with the author of this thesis, Jan Carl Budich and Emil J. Bergholtz, published in Physical Review B on April 24 2019, and Hyperbolic nodal band structures and knot invariants, written by the author of this thesis, together with Lukas Rødland, Gregory Arone, Jan Carl Budich and Emil J. Bergholtz, published in SciPost Physics August 8 2019. An introduction to gapless topological phases in the Hermitian regime, focusing on Weyl semimetals, their classification and surface states, is provided. Then, the light is brought to non-Hermitian operators and the differences from their conventional Hermitian counterpart, such as the two different set of eigenvectors bi-orthogonal to each other, exceptional eigenvalue degeneracies and some of their consequences, are explained. Afterwards, these operators are applied to dissipative physical system, and some of the striking differences from the conventional Hermitian systems are highlighted, the main focus being the possibly non-trivial topology of the 1D exceptional eigenvalue degeneracies. In order to be somewhat self contained, a brief conceptual introduction to the utilized concepts of knot theory is given, and lastly, further research directions and possible experimental realization of the considered systems are discussed.

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5

Putta, Sunil Kumar. "Nodal Resistance Measurement System". Thesis, University of North Texas, 2005. https://digital.library.unt.edu/ark:/67531/metadc5568/.

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The latest development in the measurement techniques has resulted in fast improvements in the instruments used for measurement of various electrical quantities. A common problem in such instruments is the automation of acquiring, retrieving and controlling the measurements by a computer or a laptop. In this study, nodal resistance measurement (NRM) system is developed to solve the above problem. The purpose of this study is to design and develop a compact electronic board, which measures electrical resistance, and a computer or a laptop controls the board. For the above purpose, surface nodal points are created on the surface of the sample electrically conductive material. The nodal points are connected to the compact electronic board and this board is connected to the computer. The user selects the nodal points, from the computer, between which the NRM system measures the electrical resistance and displays the measured quantity on the computer.

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6

ZHAO, YAN. "Deformations of nodal surfaces". Doctoral thesis, Università degli Studi di Milano, 2016. http://hdl.handle.net/2434/453882.

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In this thesis, we studied the Hodge theory and deformation theory of nodal surfaces. We showed that nodal surfaces in the projective 3-space satisfy the infinitesimal Torelli property. We considered families of examples of even nodal surfaces, that is, those endowed with a double cover branched on the nodes. We gave a new geometrical construction of even 56-nodal sextic surfaces, while we proved, using existing constructions, that the sub-Hodge structure of type (1,26,1) on the double cover S of any even 40-nodal sextic surface cannot be simple. We also demonstrated ways to compute sheaves of differential forms on singular varieties using Saito's theory of mixed Hodge modules.

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7

Komendarczyk, Rafal. "Nodal sets and contact structures". Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-05192006-231553/.

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Thesis (Ph. D.)--Mathematics, Georgia Institute of Technology, 2007.
Belegradek, Igor, Committee Member ; Ghrist, Robert, Committee Chair ; Harrell, Evans, Committee Member ; Etnyre, John, Committee Member ; Symington, Margaret, Committee Co-Chair.

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8

Andersson, Linn. "Nodal governance och svensk terrorismbekämpning". Thesis, Försvarshögskolan, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:fhs:diva-3496.

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Den här uppsatsen handlar om nodal governance som teori och analysverktyg. Syftet med uppsatsen är att undersöka på vilket sätt nodal governance är användbart i analysen av en svensk förvaltningskontext där främst offentliga aktörer samverkar och vilka teoretiska och metodologiska problem det eventuellt för med sig. Teorin har applicerats på en fallstudie som analyserar ett fall; svensk terrorismbekämpning. Analysen har visat att visat på teoretiska utvecklingsmöjligheter för nodal governance. Dessutom har förslag till förfining av analysverktyget kunnat presenteras. Studien har visat på möjligheterna och begränsningarna för nodal governance att beskriva och förklara den komplexa förvaltningsmiljö terrorismbekämpning organiseras i.

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9

Williams, Ian George. "Nodal domains of quantum maps". Thesis, University of Bristol, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.435420.

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10

Beal, Craig Rubidge. "Improved rehomogenization techniques for nodal methods". Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/19277.

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11

Bourget, Alain. "Nodal statistics for the Lame ensemble". Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=37872.

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The Lame polynomials naturally arise when separating variables in Laplace's equation in elliptic-spherical coordinates. The products of these polynomials form a class of spherical harmonics, which are the joint eigenfunctions of a quantum completely integrable system of commuting, second-order differential operators P0 = DSN , P2,..., PN -1 acting on Cinfinity( SN ). These operators depend on parameters and thus constitute an ensemble.
In the main result presented in this thesis, we compute the limiting mean level spacings distribution for the zeroes of Lame polynomials in various thermodynamic, asymptotic regimes. We give results both in the mean and pointwise, for an asymptotically full set of values of the parameters. As an application, we compute the limiting level spacings distribution of the zeroes of Van Vleck polynomials.

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12

Biyikoglu, Türker, Josef Leydold e Peter F. Stadler. "Nodal Domain Theorems and Bipartite Subgraphs". Department of Statistics and Mathematics, Abt. f. Angewandte Statistik u. Datenverarbeitung, WU Vienna University of Economics and Business, 2005. http://epub.wu.ac.at/626/1/document.pdf.

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The Discrete Nodal Domain Theorem states that an eigenfunction of the k-th largest eigenvalue of a generalized graph Laplacian has at most k (weak) nodal domains. We show that the number of strong nodal domains cannot exceed the size of a maximal induced bipartite subgraph and that this bound is sharp for generalized graph Laplacians. Similarly, the number of weak nodal domains is bounded by the size of a maximal bipartite minor. (author's abstract)
Series: Preprint Series / Department of Applied Statistics and Data Processing

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13

Davids, Virginia. "Molecular detection of melanoma nodal metastases". Master's thesis, University of Cape Town, 2002. http://hdl.handle.net/11427/3375.

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Includes bibliography.
The aim of this study was to develop a practical and reproducible multi-marker RT-PCR essay, with the emphasis on achieving maximum specificity for the detection of melanoma nodal metastases. A novel protocol for the efficient homogenisation of nodal tissue was developed, with clinical applicability as the objective.

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14

El, Hajj Layan. "Intersection bounds for nodal sets of Eigenfunctions". Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=107810.

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We consider the zeros of a Neumann eigenfunction φ_λ on an analytic domainsolving the equation -∆ φ_λ =λ^2 φ_λ. We count the number n(λ;H) of intersection points of the nodal lines of φ_λ (components of the nodal set) with a fixed real analytic curve H contained in the interior of the domain. We identify a large family of curves H, namely C^ω-homotopic curves to the boundary, for which the nodal intersection bound for n(λ;H) is O(λ). This bound is consistent with Yau's famous conjecture on the measure of the nodal set.
On considère les zéros d'une fonction propre de Neumann φ_λ d'un domaine analytique , solution de l'équation -∆ φ_λ =λ^2 φ_λ. On compte le nombre d'intersectionn (λ;H) de lignes nodales des fonctions propres de Neumann (composantes de l'ensemble nodal) avec une courbe fixe analytique réelle H contenue à l'intérieur du domaine. On identifie explicitement une grande famille de courbes pour lesquelles une borne pour l'intersection nodale n(λ;H) est O(λ). Cette borne est compatible avec la conjecture célèbre de Yau sur la mesure de l'ensemble nodal.

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15

Biyikoglu, Türker. "A Discrete Nodal Domain Theorem for Trees". Department of Statistics and Mathematics, Abt. f. Angewandte Statistik u. Datenverarbeitung, WU Vienna University of Economics and Business, 2002. http://epub.wu.ac.at/1270/1/document.pdf.

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Let G be a connected graph with n vertices and let x=(x1, ..., xn) be a real vector. A positive (negative) sign graph of the vector x is a maximal connected subgraph of G on vertices xi>0 (xi<0). For an eigenvalue of a generalized Laplacian of a tree: We characterize the maximal number of sign graphs of an eigenvector. We give an O(n2) time algorithm to find an eigenvector with maximum number of sign graphs and we show that finding an eigenvector with minimum number of sign graphs is an NP-complete problem. (author's abstract)
Series: Preprint Series / Department of Applied Statistics and Data Processing

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16

Smith, Andrew. "The fluid mechanics of embryonic nodal cilia". Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4626/.

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Symmetry breaking of the left-right body axis is a crucial step in development for many vertebrate species. In many this is initiated with a directional cilia-driven fluid flow in the organising structure. This work focuses on the mouse and the zebrafish organising structures, the node and Kupffer's vesicle, wherein cilia perform a tilted rotation producing an asymmetric flow. Using singularities of Stokes flow, slender body theory and the boundary integral equation, a computational model of flow in the mouse node for a range of cilia configurations simulating developmental stages is developed and run on the University of Birmingham's cluster, BlueBEAR. The results show the emergence of a directional flow as the cilia tilt increases. To model the Kupffer's vesicle the regularised boundary integral equation is used with a mesh representation of the entire domain to investigate potential cilia mechanisms that produce the observed flow as there is not a consensus. The results show that a combination of the experimental observations could be a sufficient mechanism. This model is expanded using observations of cilia with two rotation frequencies which are incorporated by allowing such cilia to ‘wobble’. This wobble accentuates the asymmetric flow in wildtype embryos and diminishes it in mutant embryos. All of these results agree well with experiment suggesting that vertebrates develop a combination of rotation mechanisms in their organising structures before an appropriate symmetry breaking flow is established.

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17

Palmtag, Scott P. (Scott Parker). "Advanced nodal methods for MOX fuel analysis". Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/9400.

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18

Jung, Sunghwan. "Growing crack analyses using nodal release technique". Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/38075.

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19

Radford, Todd C. (Todd Craig) 1977. "Wireless nodal sensing for civil engineering systems". Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/85747.

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20

Uchoa, Bruno. "Supercondutividade nodal em metais de transição dicalcogenados". [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/277832.

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Orientador: Guillermo Gerardo Cabrera Oyarzun
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin
Made available in DSpace on 2018-09-24T19:06:18Z (GMT). No. of bitstreams: 1 Uchoa_Bruno_D.pdf: 3173776 bytes, checksum: bbc84ac454d01ce5ee4aa4ae8b9d5b42 (MD5) Previous issue date: 2004
Resumo: Investigamos os efeitos macroscópicos de ondas das densidade de carga ( CDW) e da supercondutividade em sistemas organizados em planos que exibem quebra da simetria de inversão da rede (o que permitiria o aparecimento de piezoeletricidade), como nos metais de transição dicalcogenados (TMDs). Partindo da teoria de Ginzburg-Landau com dependência temporal a baixas temperaturas, estudamos como as distorções da rede e os modos coletivos de baixa energia da CDW se acoplam ao parâmetro de ordem supercondutor na presença de campos eletromagnéticos. Demonstramos que a supercondutividade e a piezoeletricidade podem coexistir nesses metais singulares. Além disso, este estudo indica a natureza do ponto crítico quântico entre a fase CDW comensurá.vel e a fase de faixas de carga, observado em função da pressão aplicada. Estes resultados são utilizados para fundamentar um modelo microscópico que unifica a supercondutividade às fases de CDW nos TMDs. Baseados na natureza do acoplamento elétron-fônon e na topologia peculiar da superfície de Fermi, propomos que o gap de CDW tem simetria f e quebra a simetria de inversão da rede na fase disorcida. As quase- partículas da teoria são férmions de Dirac definidos pelas exitações elementares da CDW na vizinhaça dos nós da superfície de Fermi, onde o gap da CDW se fecha. O estado supercondutor é formado pela atração entre férmions de Dirac através de fônons virtuais mediados pelo acoplamento piezoelétrico. Segundo esta teoria, as propriedades de transporte e o tempo de meia-vida das excitações de quase-partícula mostram fortes desvios em relação à teoria do líquido de Fermi
Abstract: We investigate the macroscopic effects of charge density waves (CDW) and superconductivity in layered superconducting systems with broken lattice inversion symmetry (allowing for piezoelectricity) such as two dimensional (2D) transition metal dichalcogenides (TMD). We work with the low temperature time dependent Ginzburg-Landau theory and study the coupling of lattice distortions and low energy CDW collective modes to the superconducting order parameter in the presence of electromagnetic fields. We show that superconductivity and piezoelectricity can coexist in these singular metals. Furthermore, our study indicates the nature of the quantum phase transition between a commensurate CDW phase and the stripe phase that has been observed as a function of applied pressure. These results are used to support a microscopic unified picture with superconductivity and CDW phases in TMD. Based on the nature of the electron-phonon coupling and Fermi surface topology, we propose a f-wave symmetry CDW gap which breakes the lattice inversion symmetry in the distorted phase. The quasiparticles are Dirac fennions defined by the elementary excitations of the CDW in the vicinity of the Fermi surface nodes, where the CDW gap is zero. The superconducting state has its origin in virtual phonon attraction of the Dirac fermions, mediated by the piezoelectric coupling. According to this theory, the transport properties and the quasiparticles life-time show strong deviations from the Fermi liquid theory
Doutorado
Física
Doutor em Ciências

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21

Biyikoglu, Türker, Wim Hordijk, Josef Leydold, Tomaz Pisanski e Peter F. Stadler. "Graph Laplacians, Nodal Domains, and Hyperplane Arrangements". Department of Statistics and Mathematics, Abt. f. Angewandte Statistik u. Datenverarbeitung, WU Vienna University of Economics and Business, 2002. http://epub.wu.ac.at/1036/1/document.pdf.

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Eigenvectors of the Laplacian of a graph G have received increasing attention in the recent past. Here we investigate their so-called nodal domains, i.e., the connected components of the maximal induced subgraphs of G on which an eigenvector \psi does not change sign. An analogue of Courant's nodal domain theorem provides upper bounds on the number of nodal domains depending on the location of \psi in the spectrum. This bound, however, is not sharp in general. In this contribution we consider the problem of computing minimal and maximal numbers of nodal domains for a particular graph. The class of Boolean Hypercubes is discussed in detail. We find that, despite the simplicity of this graph class, for which complete spectral information is available, the computations are still non-trivial. Nevertheless, we obtained some new results and a number of conjectures. (author's abstract)
Series: Preprint Series / Department of Applied Statistics and Data Processing

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22

Enani, Mohammad A. "MURR nodal analysis with simple interactive simulation /". free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9841283.

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23

Arnold, Walter. "Tumorvaskularisation als Prognosefaktor? : eine morphometrische Fall-Kontroll-Studie an T1/T2 -nodal-negativen und -nodal-positiven invasiven duktalen Mammakarzinomen /". Bern : [s.n.], 1997. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.

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24

Blackler, Alissa N. "Design of bone morphogenetic protein 2/nodal chimeras". Diss., [La Jolla] : University of California, San Diego, 2010. http://wwwlib.umi.com/cr/fullcit?p1477885.

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Thesis (M. S.)--University of California, San Diego, 2010.
Title from first page of PDF file (viewed July 12, 2010). Available via ProQuest Digital Dissertations. Includes bibliographical references (leaves 34-36).

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25

Zhu, Hongmei. "Courant's Nodal Line Theorem and its discrete counterparts". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ51246.pdf.

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26

Kaveh-Khorie, Siamak. "Nuclear reactor kinetics based on hierarchical nodal analysis". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0016/NQ57380.pdf.

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27

Koh, Dow-Mu. "Nodal Staging in Rectal Cancer Using MR Imaging". Thesis, Institute of Cancer Research (University Of London), 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498611.

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28

Karageorge, Panos Demetrios. "On the geometric content on the nodal sequence". Thesis, University of Bristol, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.500417.

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29

Jeannequin, Nicolas. "Nodal Spectral Element Method Applied To Electrocardiological Models". Thesis, University of Oxford, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.526068.

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30

Maffucci, Riccardo Walter. "Nodal lines and surfaces of arithmetic random waves". Thesis, King's College London (University of London), 2018. https://kclpure.kcl.ac.uk/portal/en/theses/nodal-lines-and-surfaces-of-arithmetic-random-waves(daf91406-6414-4ca5-ae7f-78e36eb5632e).html.

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This thesis discusses various aspects of nodal sets of random Gaussian Laplace eigenfunctions (‘arithmetic random waves’) on the two- and three-dimensional tori. The first problem concerns the number of nodal intersections against a straight line segment in two dimensions. The expected intersections number, against any smooth curve, is universally proportional to the length of the ref-erence curve, times the wavenumber, independent of the geometry. I bounded the variance in the case of a straight line with rational slope. Without assuming rational slope, I proved that the same bound holds unconditionally for a density one sequence of energies, and conditionally for all energies. The three-dimensional analogue of the first problem is the study of the nodal intersections variance against a straight line segment on the three dimensional torus. I gave a bound for rational lines. For irrational lines, I proved an uncon-ditional result, and a stronger conditional result. I also found a better bound for irrational lines (a1, a2, a3) where a2/a1 is rational. The third problem is work in collaboration with J. Benatar. We studied the area of the nodal set in the three dimensional case. The expected area is proportional to the square root of the eigenvalue. We established an asymptotic formula for the nodal area variance. The methods involve the theory of random processes, the study of the covari-ance function and application of Kac-Rice formulas. The problems are closely related to the theory of lattice points on circles and spheres. I proved upper bounds for the number of lattice points on spheres that lie on a thin spher-ical segment, using Diophantine approximation. Together with J. Benatar, I bounded the number of non-degenerate 4-correlations, and 6-correlations, of lat-tice points on spheres.

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Shatilla, Youssef A. (Youssef Abdel-Moneim). "A simple quadratic nodal model for hexagonal geometry". Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/34317.

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32

KITAGAWA, DAIJIRO. "Formation de l'espace nodal ferroviaire : paris et tokyo". Marne-la-vallée, ENPC, 1999. http://www.theses.fr/1999ENPC9906.

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Les nuds des reseaux sont devenus aujourd'hui un fondement de l'espace regional a paris et tokyo. Surtout depuis l'apparition du chemin de fer, les villes contiennent des moyens de transports quotidiens qui ne fonctionnent plus a leur echelle, mais a d'autres, plus vaste, regionale ou nationale. L'integration des reseaux dans la ville, conflictuelle ou non, n'etait que ponctuelle. Avec l'augmentation de la mobilite humaine et des distances parcourues et a parcourir, elle commence a se generaliser, assurant une dynamique urbaine et eventuellement le developpement urbain de la ville. Les nuds de reseaux peuvent alors etre consideres comme un des elements-cles des nouvelles organisations regionale, nationale, etc. Il s'agit soit d'une rupture historique de l'organisation spatiale - de l'homogeneite a la nodalite - (paris), soit d'une continuite de l'evolution spatiale (tokyo). Nous avons cherche, au cours de ce travail, le role des nuds de reseau dans la formation de la ville et du reseau de transport a paris et tokyo. Par consequent, l'observation des nuds met en evidence une difference entre paris et tokyo a l'echelle urbaine et regionale. La logique urbaine (geographique) a conditionne fortement la formation du reseau parisien, jusqu'a l'apparition du r. E. R. Qui a privilegie tant la logique urbaine que la logique ferroviaire (topologique) avec la creation de grands nuds / poles au centre et dans la proche banlieue. A tokyo, la logique ferroviaire etait materialisee - parfois sans coherence urbaine - au debut de l'industrialisation de la ville. Elle integra plus tard le developpement urbain grace a la formation des nuds / poles dans le centre puis dans la banlieue. La forme et la taille de tokyo evoluerent en suivant le rythme de formation des infrastructures ferroviaires. Une comparaison en termes de formation de l'espace nodal a l'echelle de la gare conduit aussi a une difference. Un nud parisien reste un point valorise ou non qui se situe au croisement des lignes ferroviaires. Un nud tokyoite est en revanche un lieu exploite par le rassemblement des lignes successivement ouvertes, articule a une aire commerciale qui l'englobe progressivement, le transformant en une partie interne d'un centre urbain.

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Josi, Johannes. "Nodal rational sextics in the real projective plane". Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS076.

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Cette thèse est consacrée à l’étude des courbes sextiques nodales, et en particulier des sextiques rationnelles, dans le plan projectif réel. Deux sextiques nodales réelles ayant k points doubles sont dites rigidement isotopes si elles peuvent être reliées par un chemin dans l’espace des sextiques nodales réelles ayant k points doubles. Le résultat principal de la première partie de la thèse donne une classification à isotopie rigide près des sextiques nodales irréductibles sans points doubles réels, généralisant la classification des sextiques non-singulières obtenue par Nikulin. La seconde partie porte sur les sextiques ayant des points doubles réels : une classification est obtenue pour les sextiques nodales séparantes, c’est-à-dire celles dont la partie réelle sépare leur complexification (l’ensemble des points complexes) en deux composantes connexes. Ce résultat est appliqué au cas des sextiques rationnelles réelles pouvant être perturbées en des sextiques maximales ou presque maximales (dans le sens de l’inégalité de Harnack). L’approche retenue repose sur l’étude des périodes des surfaces K3, se basant notamment sur le Théorème de Torelli Global de Piatetski-Shapiro et Shafarevich et le Théorème de Surjectivité de Kulikov, ainsi que sur les résultats de Nikulin portant sur les formes bilinéaires symétriques intégrales
This thesis studies nodal sextics (algebraic curves of degree six), and in particular rational sextics, in the real projective plane. Two such sextics with k nodes are called rigidly isotopic if they can be joined by a path in the space of real nodal sextics with k nodes. The main result of the first part of the thesis is a rigid isotopy classification of real nodal sextics without real nodes, generalizing Nikulin’s classification of non-singular sextics. In the second part we study sextics with real nodes and we describe the rigid isotopy classes of such sextics in the case where the sextics are dividing, i.e., their real part separates the complexification (the set of complex points) into two halves. As a main application, we give a rigid isotopy classification for those nodal real rational sextics which can be perturbed to maximal or next-to-maximal sextics in the sense of Harnack’s inequality. Our approach is based on the study of periods of K3 surfaces, drawing on the Global Torelli Theorem by Piatetski-Shapiro and Shafarevich and Kulikov’s surjectivity theorem, as well as Nikulin’s results on symmetric integral bilinear forms

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34

Wiener, Martin. "Lymphatic mapping and occult nodal metastasis in melanoma". Thesis, University of Sheffield, 2016. http://etheses.whiterose.ac.uk/13621/.

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Around 20% of patients, diagnosed with a clinically localized primary cutaneous melanoma, have occult lymph node metastases. Lymphatic mapping and sentinel node biopsy, using pre-operative lymphoscintigraphy, intra-operative blue dye injection and gamma probe localization, in most cases identifies the node or nodes most likely to contain occult metastases, if present. The presence or absence of such metastases is the most powerful prognostic indicator in this group of patients. However, a number of other factors related to the patient and the primary melanoma can be used to determine prognosis. It is therefore important that the quality of lymphatic mapping is maximized and information gained from sentinel node biopsy is used to best effect, so that advice and treatment can be tailored to the individual patient. The studies contained within this thesis represent an attempt to improve the quality and individualization of care. The technique of lymphatic mapping using lymphoscintigraphy has been critically analysed to identify sources of inaccuracy. The frequency and causes of failure to identify sentinel nodes using lymphoscintigraphy have been determined in a large series of patients. The lymphatic drainage patterns from the head and neck have been investigated, using the forehead and its subdivisions, in order to produce new recommendations for selective neck dissection. The relative importance of clinical and pathological factors in sentinel node positive patients and the significance of nodal metastasis beyond sentinel nodes have been determined. A new prognostic classification or survival tree has been developed for patients with occult nodal metastases and then validated in a separate population. This allows four distinct prognostic groups with 5-year survival ranging from over 90% to around 20% to be identified. The prognostic groups differentiate patients who are at high and low risk of having occult distant metastases and so could be used to select patients for entry into clinical trials of adjuvant therapies as well as to determine who should receive existing adjuvant therapies. The survival tree has been compared with currently available prognostic tools with favourable results.

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35

FLAMINI, FLAMINIO. "Families of nodal curves on smooth projective surfaces". Doctoral thesis, Università degli Studi di Roma "Tor Vergata", 2000. http://hdl.handle.net/2108/74808.

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36

Yndestad, Harald. "The Lunar Nodal Cycle Influence on the Barents Sea". Doctoral thesis, Norwegian University of Science and Technology, Faculty of Social Sciences and Technology Management, 2004. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-384.

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The Barents Sea contains one of the most productive marine areas in the world. For centuries, Northeast Arctic cod and Norwegian spring spawning herring have been of vital importance for the Norwegian fish export industry and hence economic growth in Norway. It has been common knowledge that the biomass of different Barents Sea species experiences both shortand long-term fluctuations. These fluctuations have been explained by changes in herring cycles and cod cycles, or by the introduction of new fishing equipment, and more. Norwegian marine research began in earnest at the beginning of the 19th century. The main task for researchers was to discover how nature influenced cod stocks and the effects these fluctuations had on the lives of people who depended on fishing for a living. Nearly 100 years later, scientists still disagree over the causes for the biomass fluctuations in the Barents Sea. At the same time, marine research has produced long time series, which can now be analyzed using new methods. This thesis represents an investigation of a number of long time series of Arctic climate indicators and biomasses in the Barents Sea. The purpose of this analysis has been to identify a potential stationary cycle in the biomasses. A stationary cycle in the biomass allows for expanded possibilities for better long-term biomass forecasting.

The methods are based on general systems theory, analysis of systems dynamics and a wavelet analysis of time series. The wavelet analysis has identified the cycle time and the cycle phase of the dominant cycles in the time series. The phase-relation between the identified cycles contains information abort the dynamic chain of events between climate indicators and the biomasses in the Barents Sea.

The investigation has identified harmonic and sub-harmonic cycles of the 18.6-year lunar nodal cycle in all analyzed time series. The identified lunar nodal spectrum is explained by a gravity force from the 18.6-year lunar nodal cycle as the First Cause. The energy from the 18.6-year gravity force from the moon introduces a chain of oscillating events. The oscillating gravity introduces a lunar nodal spectrum in the lunar nodal tide and the polar position. A wavelet analysis of time series indicates that movement of the polar position introduces a new lunar nodal spectrum of circulating water in the Arctic Ocean. This circulation water interacts with the 18.6-year lunar nodal tide in the Atlantic Ocean and introduces an oscillation in the extent of Arctic ice, and an oscillation in the inflow of the Atlantic Ocean to the Barents Sea. The lunar nodal spectrum of Atlantic inflow introduces a lunar nodal spectrum in the Barents Sea ecology system. Analysis of the biomass in the Barents Sea shows that long-term growth, reduction and collapse are associated with the phase-relation between the biomass eigen dynamics and the lunar nodal spectrum of Atlantic inflow.

Papers I - VI reprinted with kind permission of Elsevier, www.sciencedirect.com

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37

Henry, Allan F. "Continued development of nodal methods for nuclear reactor analysis". MIT Energy Lab, 1986. http://hdl.handle.net/1721.1/27229.

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38

Yuen, Po-wing. "The study of nodal metastasis of oral tongue carcinoma". Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B39793837.

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39

Kritchevski, Evgenij. "Nodal statistics of Heine-Stieltjes and Van Vleck polynomials". Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81348.

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We study the polynomial solutions of the Lame differential equation Azy'' z+2Bz y'z+C zyz=0 where A(z), B( z), C(z) ∈ C [z] are polynomials of degree N + 1, N and N - 1 respectively. We review classical results concerning the location of the zeros of y(z) and C(z) and their electrostatic interpretation. Asymptotic distribution of the zeros as the degree K of y(z) approaches infinity is then discussed. We also derive numerical methods that allow us to compute solutions of high degree K and present a variety of new fine experimental results such as the asymptotic nearest neighbor spacing distribution and the description of complex configurations.

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40

Andrew, Rebecca Louise. "The role of Arkadia in the nodal signal pathway". Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401212.

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41

Yuen, Po-wing, e 袁寶榮. "The study of nodal metastasis of oral tongue carcinoma". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B39793837.

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42

Wu, Xuewei, e 吴雪伟. "Isthmin, a novel extracellular regulator in nodal signaling pathway". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://sunzi.lib.hku.hk/hkuto/record/B45586573.

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43

Gao, Yuan Gene, e 高远. "Type IIA procollagen and the regulation of nodal signaling". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B45982272.

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44

Mohamed, Amr S. (Amr Saad Galal). "A transient nodal method accounting for multigroup transport effects". Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/32592.

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45

Pellegrino, Paulo Eduardo Mota. "Estudo de estabilidade atraves do balanço nodal de potencia". [s.n.], 1995. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259911.

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Orientador: Sigmar Maurer Deckmann
Dissertação (mestrado) - Universidade Estadual de Campinas. Faculdade de Engenharia Eletrica
Made available in DSpace on 2018-07-20T10:19:31Z (GMT). No. of bitstreams: 1 Pellegrino_PauloEduardoMota_M.pdf: 4742203 bytes, checksum: 0efad1df4c3d10aa2ffb45775e38d387 (MD5) Previous issue date: 1995
Resumo: Este trabalho tem como meta descrever um método para solução dos problemas de estabilidade de médio e longo prazo utilizando o conceito de Balanço Nodal de Potência BNP. A base deste novo método é sua formulação como um problema de fluxo de potência e o uso dos conhecidos algoritmos do fluxo de potência para sua solução, especialmente um modelamento desacoplado. A necessidade da representação do barramento infinito é evitado com a utilização da abordagem do balanço de potência. O desempenho deste método é primeiramente discutido para um gerador ligado a um barramento infinito e posteriormente estendido a uma rede multinodal
Abstract: The goal of this work is to describe a method to solve stability problems of mid and long terms using Nodal Power Mismatch (NPM) concept. The basis of the new method is its formulation as a power flow problem and the use of the well known power flow algorithms for the solution, using a decoupled modelling. The need of an infinitebus representation is avoided by the use of the power mismatch approach. The performance of this method is first discussed for a singlegenerator connected to an infinitebus and then extended for a multinodal network
Mestrado
Mestre em Engenharia Elétrica

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46

Morazzo, Sofia Faes. "A potencial função do nodal na endometrose da égua". Master's thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2017. http://hdl.handle.net/10400.5/14039.

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Dissertação de Mestrado Integrado em Medicina Veterinária
Alguns membros da superfamília do TGFβ, tais como o Nodal e o TGFβ1, têm um papel importante na reprodução da égua, sendo que a sua disfunção pode contribuir para patologias uterinas. A endometrose é uma doença degenerativa em que o endométrio normal vai sendo substituído por tecido fibrótico. O objectivo deste estudo consistiu em avaliar: (i) como o Nodal pode influenciar o nível de mRNA dos recetores da PGE2 (EP2; EP4), do TGFβ1 (ALK5; TGFRII), e os próprios (ALK4; ALK7), e ainda, a secreção de prostaglandinas (PGs; PGE2; PGF2α) no endométrio equino; e (ii) como a fase do ciclo éstrico e grau de endometrose pode influenciar estas vias. Endométrios da fase folicular (FF; n=6) e da fase lútea (FL; n=6) foram classificados de acordo com o sistema de Kenney e Doig em categorias I e IIA (n=7), ou IIB e III (n=5). Os explantes foram incubados (24h; 37ºC, 5% CO2) com TNFα, ocitocina ou Nodal (0.1;1;10 ng/mL). A expressão de mRNA foi avaliada por qRT-PCR e a medição de prostaglandinas por ELISA. Em endométrios de categoria I/IIA, o Nodal inibiu a expressão génica de EP2, EP4 e ALK4 e estimulou a de TGFRII, em ambas as fases do ciclo éstrico; e estimulou também os níveis de mRNA de ALK5 e ALK7, apenas na FL. Em endométrios de categoria IIB/III, o Nodal estimulou os níveis de mRNA de EP2, EP4 e ALK5, na FF, e de ALK4 e ALK7, na FL, embora tenha inibido TGFRII e ALK4, na FF, e EP2, EP4, ALK5 e TGFRII na FL. O Nodal na concentração testada mais baixa (0.1ng/mL) estimulou a produção de PGE2 na FF e FL, enquanto que numa concentração superior a inibiu na FF (1ng/mL). A produção de PGF2α foi estimulada na FL com Nodal (0.1 e 10ng/mL). Concluindo, o Nodal parece estar envolvido na endometrose da égua, por afetar negativamente a sinalização da PGE2 anti-fibrótica e positivamente a da citocina pró-fibrótica TGFβ1 e a produção de PGF2α.
ABSTRACT - THE POTENCIAL ROLE OF NODAL IN MAR ENDOMETROSIS - Members of TGFβ superfamily, as Nodal and TGFβ1, have an important role in mare´s reproduction, and as such, their dysfunction may contribute for uterine pathologies. Endometrosis is a degenerative process with a switch of normal endometrium to fibrotic tissue. The aim of the study was to assess: (i) how Nodal may influence the receptors of PGE2 (EP2; EP4), TGFβ1 (ALK5; TGFRII), and its own (ALK4; ALK7) mRNA level and prostaglandin (PG) secretion in equine endometrium; and (ii) estrous cycle and endometrosis influence on these vias. Endometria from follicular (FP; n=6) and mid luteal phases (MLP; n=6) were classified in Kenney and Doig´s categories (cat) I and IIA (n=7), or IIB and III (n=5). Endometrium explants were incubated (24h; 37ºC, 5% CO2) with TNF, oxytocin or Nodal (0.1, 1; 10ng/mL). The mRNA expression was assessed by qRT-PCR and ELISA was used for PG measurement. In cat I/IIA endometria, Nodal down-regulated EP2, EP4 and ALK4 mRNA expression and up-regulated TGFRII in both FP and MLP; and ALK5 and ALK7 only in MLP. In cat IIB/III, Nodal up-regulated mRNA levels of EP2, EP4 and ALK5 in FP, and ALK4 and ALK7 in MLP, whereas it inhibited TGFRII and ALK4 in FP, and EP2, EP4, ALK5 and TGFRII in MLP. Nodal (0.1ng/mL) stimulated PGE2 production in both FF and FL, while at a higher concentration (1ng/mL) it decreased PGE2 in FP. The production of PGF2α increased in MLP with Nodal stimulation (at 0.1 and 10ng/mL). In conclusion, Nodal may be involved in endometrosis in the mare, by impairment of anti-fibrotic PGE2 and pro-fibrotic TGFβ1 signaling pathways and increasing PGF2α production.
N/A

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47

Rogers, Katherine Wallace. "Mesendoderm Patterning by the Nodal/Lefty Activator/Inhibitor System". Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:14226039.

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During zebrafish embryogenesis, a gradient of the secreted TGFβ ligand Nodal induces expression of mesendodermal genes in an exposure-dependent manner, and also induces expression of the secreted Nodal feedback inhibitor Lefty. The long-range Lefty gradient dampens signaling by the shorter-range Nodal gradient, and together they are required for proper patterning of the germ layers. My research has addressed two fundamental questions about this patterning system: 1) How are the distinct ranges of Nodal and Lefty achieved, and 2) What is the role of Lefty-mediated feedback inhibition in this patterning system? To understand why Nodal and Lefty have different activity ranges, we developed fluorescent fusion proteins and microscopy techniques to measure the distributions, degradation rates, and diffusion coefficients of Nodal and Lefty in living zebrafish embryos. We found that Nodal-GFP forms a shorter-range gradient than Lefty-GFP in vivo, consistent with the shorter activity range of Nodal. The extracellular half-lives of Nodal-Dendra2 and Lefty-Dendra2 are similar, but the diffusion coefficient of Nodal-GFP is much lower than that of Lefty-GFP. Differential diffusivity therefore explains the shorter range of Nodal compared to Lefty. To better understand the function of Lefty during vertebrate embryogenesis, we generated and analyzed zebrafish lefty mutants. Although patterning is highly robust to lefty gene dosage, complete loss of lefty causes upregulation of mesendodermal genes during gastrulation, aberrant cell internalization, and severe patterning defects, consistent with excess Nodal signaling. Mutations in nodal partially suppress patterning defects caused by lefty loss, and lefty mutants can be fully rescued by ectopic expression of lefty-gfp or by treatment with low levels of a Nodal inhibitor drug. Further, lefty expression is highly responsive to Nodal signaling. These results demonstrate that Lefty acts as a fast-responding, global dampener of Nodal signaling that restricts mesendoderm specification.

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48

Leydold, Josef. "On the number of nodal domains of spherical harmonics". Institut für Statistik und Mathematik, Abt. f. Angewandte Statistik u. Datenverarbeitung, WU Vienna University of Economics and Business, 1993. http://epub.wu.ac.at/1050/1/document.pdf.

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It is well known that the n-th eigenfunction to one-dimensional Sturm-Liouville eigenvalue problems has exactly n-1 nodes, i.e. non-degenerate zeros. For higher dimensions, it is much more complicated to obtain general statements on the zeros of eigenfunctions. The author states a new conjecture on the number of nodal domains of spherical harmonics, i.e. of connected components of S^2 \ N(u) with the nodal set N(u) = (x in S^2 : u(x) = 0) of the eigenfunction u, and proves it for the first six eigenvalues. It is a sharp upper bound, thus improving known bounds as the Courant nodal domain theorem, see S. Y. Cheng, Comment. Math. Helv. 51, 43-55 (1976; Zbl 334.35022). The proof uses facts on real projective plane algebraic curves (see D. A. Gudkov, Usp. Mat. Nauk 29(4), 3-79, Russian Math. Surveys 29(4), 1-79 (1979; Zbl 316.14018)), because they are the zero sets of homogeneous polynomials, and the spherical harmonics are the restrictions of spherical harmonic homogeneous polynomials in the space to the plane.
Series: Preprint Series / Department of Applied Statistics and Data Processing

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49

Ilas, Germina. "A Monte Carlo based nodal diffusion model for criticality analysis and application of high-order cross section homogenization method of two-group nodal diffusion". Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/16092.

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50

Muñoz, Castañeda Ángel Luis [Verfasser]. "Principal G-bundles on nodal curves / Ángel Luis Muñoz Castañeda". Berlin : Freie Universität Berlin, 2017. http://d-nb.info/1139709437/34.

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