1,720,963 research outputs found
Q−orthogonal dualities for asymmetric particle systems
Full text linkWe study a class of interacting particle systems with asymmetric interaction showing a self-duality property. The class includes the ASEP(q, θ), asymmetric exclusion process, with a repulsive interaction, allowing up to θ ∈ N particles in each site, and the ASIP(q, θ), θ ∈ R+, asymmetric inclusion process, that is its attractive counterpart. We extend to the asymmetric setting the investigation of orthogonal duality properties done in [8] for symmetric processes. The analysis leads to multivariate q−analogues of Krawtchouk polynomials and Meixner polynomials as orthogonal duality functions for the generalized asymmetric exclusion process and its asymmetric inclusion version, respectively. We also show how the q-Krawtchouk orthogonality relations can be used to compute exponential moments and correlations of ASEP(q, θ).Analysi
De Rogers-Ramanujan identiteiten
No full textApplied MathematicsDelft Institute of Applied MathematicsElectrical Engineering, Mathematics and Computer Scienc
The Vector-Valued Big q -Jacobi Transform
Full text linkBig q-Jacobi functions are eigenfunctions of a second-order q-difference operator L. We study L as an unbounded self-adjoint operator on an L-2-space of functions on R with a discrete measure. We describe explicitly the spectral decomposition of L using an integral transform F with two different big q-Jacobi functions as a kernel, and we construct the inverse of F.Delft Institute of Applied MathematicsElectrical Engineering, Mathematics and Computer Scienc
Algebraïsche sommatieformules voor 1/pi
No full textPrecieze uitwerkingen van twee indrukwekkende sommatieformules voor 1/pi volgens de methode van de gebroeders Borwein. 1 van de formules komt van de hand van Ramanujan. Veel details en behandeling van o.a. gamma- en betafuncties, Euler integraal, hypergeometrische reeks, elliptische integralen en bijbehorende transformaties, Legendre's relatie, singuliere waarde (functies), modulaire vergelijkingen en de relatie tussen het rekenkundig-meetkundig gemiddelde en formules voor 1/pi.Applied MathematicsMathematicsElectrical Engineering, Mathematics and Computer Scienc
Lie algebra su(2) - Het energiespectrum van een waterstofatoom berekenen
No full textDeze tekst geeft een introductie over de Lie algebra su(2). Met deze introductie, en met behulp van representaties en tensorproducten wordt uiteindelijk het energiespectrum van een waterstofatoom berekend.Applied mathematicsElectrical Engineering, Mathematics and Computer Scienc
Quantum Analogs of Tensor Product Representations of su(1,1)
No full textWe study representations of U_q(su(1,1)) that can be considered as quantum analogs of tensor products of irreducible *-representations of the Lie algebra su(1,1). We determine the decomposition of these representations into irreducible *-representations of U_q(su(1,1)) by diagonalizing the action of the Casimir operator on suitable subspaces of the representation spaces. This leads to an interpretation of the big q-Jacobi polynomials and big q-Jacobi functions as quantum analogs of Clebsch-Gordan coefficients
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
