292 research outputs found
Interview with Florent Perek
No full textProfessor Florent Perek has a PhD in English and General Linguistics (University of Freiburg) and is a Lecturer in Cognitive Linguistics at the Department of English Language and Applied Linguistics at University of Birmingham, UK. Professor Perek is the author of several articles in international peer-reviewed journals and has, among his most important publications, the 2015 book, Argument structure in usage-based construction grammar: experimental and corpus-based perspectives, edited by John Benjamins.Professor Florent Perek has a PhD in English and General Linguistics (University of Freiburg) and is a Lecturer in Cognitive Linguistics at the Department of English Language and Applied Linguistics at University of Birmingham, UK. Professor Perek is the author of several articles in international peer-reviewed journals and has, among his most important publications, the 2015 book, Argument structure in usage-based construction grammar: experimental and corpus-based perspectives, edited by John Benjamins.------------------------------------------------------------------------------------ENTREVISTA COM FLORENT PEREKFlorent Perek é Doutor em Inglês e Linguística Geral (Universidade de Freiburg, Alemanha) e Professor da área de Linguística Cognitiva do Departamento de Língua Inglesa e Linguística Aplicada na Universidade de Birmingham, no Reino Unido. Perek é autor de uma série de artigos em revistas renomadas internacionalmente e tem, entre suas importantes publicações, seu livro de 2015, o qual foi intitulado Estrutura argumental na gramática de construções baseada no uso: perspectivas experimental e baseada em corpus e foi editado pela John Benjamins.---Original em inglês
More light on the 2ν5 Raman overtone of SF6: Can a weak anisotropic spectrum be due to a strong transition anisotropy?
No full textLong known as a fully polarized band with a near vanishing depolarization ratio [η s = 0.05, W. Holzer and R. Ouillon, Chem. Phys. Lett.24, 589 (1974)], the 2ν5 Raman overtone of SF6 has so far been considered as of having a prohibitively weak anisotropic spectrum [D. P. Shelton and L. Ulivi, J. Chem. Phys.89, 149 (1988)]. Here, we report the first anisotropic spectrum of this overtone, at room temperature and for 13 gas densities ranging between 2 and 27 amagat. This spectrum is 10 times broader and 50 times weaker than the isotropic counterpart of the overtone [D. Kremer, F. Rachet, and M. Chrysos, J. Chem. Phys.138, 174308 (2013)] and its profile much more sensitive to pressure effects than the profile of the isotropic spectrum. From our measurements an accurate value for the anisotropy matrix-element |⟨000020|Δα|000000⟩| was derived and this value was found to be comparable to that of the mean-polarizability ((000020),α¯¯,(000000)) . Among other conclusions our study offers compelling evidence that, in Raman spectroscopy, highly polarized bands or tiny depolarization ratios are not necessarily incompatible with large polarizability anisotropy transition matrix-elements. Our findings and the way to analyze them suggest that new strategies should be developed on the basis of the complementarity inherent in independent incoherent Raman experiments that run with two different incident-beam polarizations, and on concerted efforts to ab initiocalculate accurate data for first and second polarizability derivatives. Values for these derivatives are still rarities in the literature of SF6
The depolarized Raman 2 nu(3) overtone of CO2: A line-mixing shape analysis
No full textIn a recent article we showed that the 2 nu(3) transition of CO2 gives rise to a Raman spectrum that is almost entirely depolarized [M. Chrysos, I. A. Verzhbitskiy, F. Rachet, and A. P. Kouzov, J. Chem. Phys. 134, 044318 (2011)]. In the present article, we go further forward in the study of this overtone by reporting a first-principles shape analysis of its depolarized spectrum at room temperature. As a first step in our analysis, a model assuming isolated Lorentzian line shapes was applied, which at low gas densities turns out to be sufficient for qualitative conclusions. As the next step, a sophisticated approach was developed on the basis of the extended strong-collision model in order to properly account for the heavy line mixing between rotational lines. Whereas a marked deviation between model and measured spectra was observed upon application of the simpler model, striking agreement even at the highest CO2 density was found on applying the sophisticated one. Accurate calculated data were used for the rotational line broadening coefficients without resort to arbitrary parameters. Values for the vibrational shift scaling linearly with the density of the gas are given
The isotropic remnant of the CO2 near-fully depolarized Raman 2v3 overtone
No full textIn a recent paper [M. Chrysos, I. A. Verzhbitskiy, F. Rachet, and A. P. Kouzov, J. Chem. Phys. 134, 044318 (2011)], we showed that, in CO2, the 2 nu(3) transition generates a Raman line spectrum that is 98% depolarized, a property in agreement with general symmetry rules. Here, we present an extensive analysis, experimental and theoretical, of the isotropic remnant of this overtone. The isotropic spectrum turned out to be 45 times less intense than its anisotropic counterpart and to have a moment that is 350 times smaller than the moment of the anisotropic spectrum, in excellent agreement with theoretical predictions. Once the measured intensity (along with other data exclusively experimental) was fed back into the formula of the moment, a value for the CO2 mean-polarizability asymmetric stretch derivative partial derivative(2)(alpha) over bar/partial derivative q(3)(2) was returned that matches the best ab initio prediction to better than 4%. Agreement, in order of magnitude, was found between the intensity reported herein and that reported in the sole prior study of this overtone [G. Tejeda, B. Mate, and S. Montero, J. Chem. Phys. 103, 568 (1995)]. (C) 2011 American Institute of Physics. [doi:10.1063/1.3557820
Coupled simulator for research on the interaction between pedestrians and (automated) vehicles
No full textDriving simulators are regarded as valuable tools for human factors research on automated driving and traffic safety. However, simulators that enable the study of human-human interactions are rare. In this study, we present an open-source coupled simulator developed in Unity. The simulator supports input from head-mounted displays, motion suits, and game controllers. It facilitates research on interactions between pedestrians and humans inside manual and automated vehicles. We present results of a demo experiment on the interaction between a passenger in an automated car equipped with an external human-machine interface, a driver of a manual car, and a pedestrian. We conclude that the newly developed open-source coupled simulator is a promising tool for future human factors research.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Human-Robot InteractionMedical Instruments & Bio-Inspired Technolog
Un consulat et ses finances. Millau (1187-1461)
No full textÀ partir d’une documentation financière riche et variée conservée aux archives municipales de Millau, Florent Garnier s’est intéressé en particulier à l’exceptionnelle série de comptes des consuls boursiers du XIIIe au XVe siècle. Ces registres sont de première importance pour connaître de la vie du consulat de Millau, de ses habitants et, plus largement, du Rouergue et du royaume pendant la guerre de Cent Ans. L’auteur met en lumière la genèse de l’administration financière millavoise, l’élaboration de règles comptables et fiscales puis leur mise en œuvre par le consulat pour collecter et gérer des ressources permanentes nécessaires au financement de ses dépenses. Florent Garnier s’est également livré à une étude prosopographique des gens des finances de cette ville médiévale. Activité exceptionnelle pour certains, placement pour d’autres, étape enfin vers les charges de consul, la gestion de l’argent urbain attire des personnes d’horizons divers. Certains trésoriers de la ville, comptables particuliers ou fermiers de l’impôt, apparaissent comme de véritables « professionnels » des finances. Dépense pour les uns, source de revenu pour d’autres, le prélèvement fiscal est également un enjeu qui s’offre aux différents acteurs de la vie municipale. Il l’est tout autant dans les relations nouées par la communauté urbaine avec le prince. Cette étude qui dépasse la simple monographie s’inscrit dans les récentes recherches menées dans le cadre de l’Occident méditerranéen. « Au fi l de cette recherche profondément novatrice, Florent Garnier s’est imposé comme l’artisan éclairé d’une méthode, l’observateur minutieux d’un milieu et le décrypteur ingénieux d’un système » Albert Rigaudière.Using the rich and varied collection of financial documents preserved in the Millau municipal archives, Florent Garnier has focussed in particular on the exceptional series of Treasurer’s accounts for the period from the 13th to the 15th century. These records are extremely important in enabling us to gain an understanding of how the Millau Treasury was run, the life of the town’s inhabitants and, more broadly, that of Rouergue and the kingdom during the Hundred Years War. The author reveals how the financial administration of Millau developed, how accounting and tax rules were formulated and then how they were implemented by the Treasury in order to collect and manage the resources which they constantly needed to finance their expenditure. Florent Garnier has also conducted a prosopographic study of the people involved in the finances of this medieval town. An exceptional activity for some, a job for others, a step closer to the post of Treasurer: the management of the town’s finances attracted a broad range of people. Some of the town’s Treasurers, who were private accountants or tax collectors known as tax farmers, appear to have been real financial ‘professionals’. The levying of taxes, which was an expense for some and a source of revenues for others, was also a task which was open to various players on the municipal scene. It was a particularly key factor in the relationships established by the urban community with the local prince. This study, which is more than a simple monograph, forms part of the research which has recently been conducted in this field in the Western Mediterranean. ‘Throughout this highly innovative research, Florent Garnier has shown himself to be a craftsman skilled in applying his chosen method, a meticulous observer of a milieuand the ingenious decoder of a system.’ (Albert Rigaudière).La abundante y variada documentación financiera que se guarda en los archivos municipales de Millau ha dado a Florent Garnier la ocasión de interesarse de forma particular en la excepcional serie de cuentas de los llamados consuls boursiers (los “cónsules de la bolsa”), que ejercieron su actividad entre los ss. XIII y XV. Estos registros son de importancia capital para saber de la vida en el Consulado de Millau, de sus habitantes y, de forma más amplia, de la antigua provincia de Rouergue y del reino de Francia durante la Guerra de los Cien Años. El autor hace un repaso por la génesis de la administración financiera del Consulado de Millau así como por la elaboración de las reglas contables y fiscales y su aplicación por parte del Consulado con el fin de recaudar y gestionar los recursos permanentes necesarios a la financiación de sus gastos. Florent Garnier se ha dedicado asimismo a un estudio prosopográfico de los hombres de finanzas de esta ciudad medieval. Cargo de prestigio o acomodo para unos, escalón para acceder al cargo de cónsul para otros, la gestión del dinero municipal atrajo a personas de orígenes diversos. Algunos de los tesoreros de la ciudad, contables particulares o recaudadores delegados, aparecen como auténticos “profesionales” de las finanzas. Gasto para unos, fuente de ingresos para otros, la recaudación tributaria es una cuestión tan crucial para los diferentes actores de la vida municipal como las relaciones que vinculan a la comunidad urbana con el príncipe. Este estudio que supera los límites de la mera monografía se enmarca dentro de las recientes investigaciones que tienen por objeto el Occidente Mediterráneo. “Florent Garnier se va imponiendo a lo largo de esta investigación profundamente innovadora como el artífice aventajado de un método, como el observador minucioso de un mundo que descifra con ingenio un sistema” (Albert Rigaudière).Le Comité pour l’histoire économique et financière est présidé par le ministre de l’Économie, des Finances et de l’Industrie, son vice-président est Maurice Lévy-Leboyer. Commission administrative : Les directeurs et chefs de service du ministère de l’Économie, des Finances et de l’Industrie, le gouverneur de la Banque de France, le directeur générale des Archives de France, le président de la Bibliothèque de France, le président de l’Imprimerie nationale. Commission scientifique : Guy Antonetti, Jean-Charles Asselain, Françoise Bayard, Christian de Boissieu, Éric Bussière, Jacques Campet, François Caron, Philippe Contamine, Agnès D’Angio-Barros, Robert Frank, Patrick Fridenson, René Girault (†), Jean-Noël Jeanneney, Jean Kerhervé, Michel Lescure, Maurice Lévy-Leboyer, Michel Margairaz, Jacques Marseille, François Monnier, Alain Plessis, Raymond Poidevin (†), Albert Rigaudière, Guy Thuillier, Jean Tulard, Denis Woronoff. Membres honoraires : Michel Aglietta, Michel Antoine, Louis Bergeron, Jean-Jacques Bienvenu, Yves Mény, Gabriel Montagnier. La mission du Comité est de contribuer à une meilleure connaissance de l’histoire de l’État et de son rôle en matière économique et financière depuis le Moyen Âge jusqu’à nos jours, de susciter des travaux scientifiques et d’en aider la diffusion
Heavy rare-gas atomic pairs and the “double penalty” issue: Isotropic Raman lineshapes by Kr2, Xe2, and KrXe at room temperature
No full textWe report absolutely calibrated isotropic Raman lineshapes for Kr2 and Xe2 and for KrXe at 294.5 K and compare them to quantum-mechanically generated lineshapes by using state-of-the-art second-order Møller-Plesset and DFT/B3LYP data sets for the induced mean dipole polarizability ᾱ . A very good agreement between the numerical and the experimental data was observed but the large uncertainty margins and the short Raman frequency interval probed in our experiment prevented us from rating on a more refined scale the performance of the tested ᾱ models. These drawbacks are inherent in isotropic Raman spectrum measurements and amplified for dissimilar pairs because, for such systems and spectra, the unreliable operation of subtracting optical signals of comparable magnitude occurs twice per Raman frequency shift value, thus penalizing twice the quality of the measured data. In light of our findings and of previously reported evidence about related electric properties in Kr2 and Xe2 and in KrXe, we are left with no doubt as to the consistency of the induced-polarizability and interatomic-potential data used for these three systems at the reported level of accuracy
Collision-induced Raman scattering and the peculiar case of neon: Anisotropic spectrum, anisotropy, and the inverse scattering problem
No full textOwing in part to the p orbitals of its filled L shell, neon has repeatedly come on stage for its peculiar properties. In the context of collision-induced Raman spectroscopy, in particular, we have shown, in a brief report published a few years ago [M. Chrysos et al., Phys. Rev. A 80, 054701 (2009)], that the room-temperature anisotropic Raman lineshape of Ne–Ne exhibits, in the far wing of the spectrum, a peculiar structure with an aspect other than a smooth wing (on a logarithmic plot) which contrasts with any of the existing studies, and whose explanation lies in the distinct way in which overlap and exchange interactions interfere with the classical electrostatic ones in making the polarizability anisotropy, α ∥ − α ⊥. Here, we delve deeper into that study by reporting data for that spectrum up to 450 cm−1 and for even- and odd-order spectral moments up to M 6, as well as quantum lineshapes, generated from SCF, CCSD, and CCSD(T) models for α ∥ − α ⊥, which are critically compared with the experiment. On account of the knowledge of the spectrum over the augmented frequency domain, we show how the inverse scattering problem can be tackled both effectively and economically, and we report an analytic function for the anisotropy whose quantum lineshape faithfully reproduces our observations
Collision-induced Raman scattering by rare-gas atoms: The isotropic spectrum of Ne–Ne and its mean polarizability
No full textWe report the room-temperature isotropic collision-induced light scattering spectrum of Ne–Ne over a wide interval of Raman shifts, and we compare it with the only available experimentalspectrum for that system as well as with spectra calculated quantum-mechanically with the employ of advanced ab initio -computed data for the incremental mean polarizability. Thespectral range previously limited to 170 cm−1 is now extended to 485 cm−1 allowing us to successfully solve the inverse-scattering problem toward an analytic model for the meanpolarizability that perfectly matches our measurements. We also report the depolarization ratio of the scattering process, lingering over the usefulness of this property for more stringent checks between the various polarizability models
On the isotropic Raman spectrum of Ar2 and how to benchmark ab initio calculations of small atomic clusters: Paradox lost
No full textThis is the long-overdue answer to the discrepancies observed between theory and experiment in Ar2 regarding both the isotropic Raman spectrum and the second refractivity virial coefficient, BR [Gaye et al., Phys. Rev. A 55, 3484 (1997)]. At the origin of this progress is the advent (posterior to 1997) of advanced computational methods for weakly interconnected neutral species at close separations. Here, we report agreement between the previously taken Raman measurements and quantum lineshapes now computed with the employ of large-scale CCSD or smartly constructed MP2 induced-polarizability data. By using these measurements as a benchmark tool, we assess the degree of performance of various other ab initio computed data for the mean polarizability α, and we show that an excellent agreement with the most recently measured value of BR is reached. We propose an even more refined model for α, which is solution of the inverse-scattering problem and whose lineshape matches exactly the measured spectrum over the entire frequency-shift range probed
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