6,415 research outputs found

    Iterated uniform finite-state transducers

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    A deterministic iterated uniform finite-state transducer (for short, iufst) operates the same length-preserving transduction on several left-to-right sweeps. The first sweep occurs on the input string, while any other sweep processes the output of the previous one. We focus on constant sweep bounded iufsts. We study their descriptional power vs. deterministic finite automata, and the state cost of implementing language operations. Then, we focus on non-constant sweep bounded iufsts, showing a nonregular language hierarchy depending on sweep complexity

    Photonic realization of a quantum finite automaton

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    We describe a physical implementation of a quantum finite automaton that recognizes a well-known family of periodic languages. The realization exploits the polarization degree of freedom of single photons and their manipulation through linear optical elements. We use techniques of confidence amplification to reduce the acceptance error probability of the automaton. It is worth remarking that the quantum finite automaton we physically realize is not only interesting per se but it turns out to be a crucial building block in many quantum finite automaton design frameworks theoretically settled in the literature

    Fluoration de l’émail in vitro par laser à rayons ultraviolets

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    28 samples of human enamel have been studied in order to measure fluoride absorption after treatment with ultraviolet radiations.Samples treated with topical application only presented limited fluoride absorption in enamel surface (up to 0,5 µm deep). The absorption rate was higher, using an U.V. lamp. In samples treated with «excimer» laser, fluoride absorption was much higher in the surface layer and occurred also deeper (3 µm).28 échantillons d’émail dentaire humain ont été analysés afin de quantifier l’absorption du fluor après traitement aux rayons ultraviolets.Les analyses ont montré que les échantillons soumis à une simple application topique présentent une absorption de fluor modeste, uniquement dans les couches superficielles de l’émail (jusqu’à 0,5 µm de profondeur). L’absorption est plus importante en utilisant une lampe à vapeur de mercure. Avec le laser «excimer», comparé aux deux autres méthodes, la fixation du fluor dans le réseau de l’émail est très supérieure en surface et se produit également en profondeur (3 µm)

    Pressurization and depressurization phases inside the plumbing system of Mount Etna volcano: Evidence from a multiparametric approach

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    During 2013 Mount Etna volcano experienced intense eruptive activity at the summit craters, foremost at the New Southeast Crater and to a minor degree at the Voragine and Bocca Nuova (BN), which took place in two cycles, February-April and September-December. In this work, we mainly focus on the period between these cycles, applying a multiparametric approach. The period from the end of April to 5 September showed a gradual increase in the amplitude of long-period (LP) events and volcanic tremor, a slight inflation testified by both tilt and GPS data, and a CO2 flux increase. Such variations were interpreted as due to a gradual pressurization of the plumbing system, from the shallowest part, where LP and volcanic tremor are located, down to about 3-9km below sea level, pressure source depths obtained by both geodetic and CO2 data. On 5 September, at the same time as a large explosion at BN, we observed an instantaneous variation of the aforementioned signals (decrease in amplitude of LP events and volcanic tremor, slight deflation, and CO2 flux decrease) and the activation of a new infrasonic source located at BN. In the light of it, the BN explosion probably caused the instantaneous end of the pressurization, and the opening of a new vent at BN, that has become a new steady source of infrasonic events. This apparently slight change in the plumbing system also led to the gradual resumption of activity at the New Southeast Crater, culminating with the second lava fountain cycle of 2013

    Rôle de la stabilométrie dans l’évaluation des corrélations entre les troubles crânio-mandibulaires (TCM) et les troubles de l’équilibre (TE)

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    We examined three groups:- 29 patients suffering from balance disorders and craniomandibular disorders but not from vestibular disease;- 21 patients suffering from balance disorders, craniomandibular disorders and vestibular disease;- 26 patients suffering from craniomandibular disorders but not from vestibular disease or balance sorders.All cases were examined by the odontologist and otoneurologist and tested by computerized stabilometry; they were reexamined after six months of therapy by an occlusal stabilization splint. The static analysis of the results shows a significative reduction of the postural oscillations in all patients.Trois groupes de patients ont été examinés :- 29 sujets présentant des TE et des TCM sans vestibulopathie;- 21 sujets présentant des TE et des TCM associés à une vestibulopathie;- 26 sujets avec TCM sans TE ni vestibulopathie.Après une visite odontologique et otoneurologique complétée par une stabilométrie assistée par ordinaeur, les 3 groupes ont tous été recontrôlés après 6 mois de thérapie avec plaque de stabilisation. L’analyse les données a permis de constater une réduction significative des oscillations posturales chez tous les patients

    L’emploi de la stabilométrie assistée par ordinateur dans le diagnostic des troubles crânio-mandibulaires (TCM)

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    The aim of this study was to evaluate the influence of the cervical region and the stomatognatic system on the balance control. We examined 35 healthy subjects and 201 balance disorder patients; of the 201 patients 60 suffered also from craniomandibular disorders (CMD) and 40 from cervical rachis disease. All cases were tested by computerized stabilometry executed in Romberg position: with closed eyes, retroflexed head and two cotton roles between the dental archs. The results show that cervical rachis disease and stomatognatic dysfunction have a significative influence on the balance control; however, this influence is smaller than that of vestibular disease; moreover, the computer stabilometry allows to measure the degree of ascending or descending correlation between the posture and stomatognatic system.Le but de cette étude a été d’évaluer l’influence de la région cervicale et de l’appareil stomatognatique sur le contrôle postural. On a examiné 35 sujets normaux et 201 patients avec troubles de l’équilibre, dont 60 présentaient aussi des troubles cranio-mandibulaires (TCM) et 40 une pathologie du rachis cervical. Tous les patients ont été soumis à un examen stabilométrique assisté par ordinateur, effectué en position de Romberg: les yeux fermés, la tête en rétroflexion, en occlusion modifiée par rouleaux interdentaires. Les résultats indiquent que les pathologies du rachis cervical et celles de l’appareil stomatognatique ont une influence significative sur le contrôle postural; toutefois, cette influence est nettement inférieure à celle des pathologies vestibulaires. Ils montrent également que la stabilométrie permet de mesurer le degré de corrélation ascendant ou descendant entre la posture et l’appareil stomatognatique

    Kinematics and strain analyses of the eastern segment of the Pernicana Fault (Mt. Etna, Italy) derived from geodetic techniques (1997-2005)

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    This paper analyses the ground deformations occurring on the eastern part of the Pernicana Fault from 1997 to 2005. This segment of the fault was monitored with three local networks based on GPS and EDM techniques. More than seventy GPS and EDM surveys were carried out during the considered period, in order to achieve a higher temporal detail of ground deformation affecting the structure. We report the comparisons among GPS and EDM surveys in terms of absolute horizontal displacements of each GPS benchmark and in terms of strain parameters for each GPS and EDM network. Ground deformation measurements detected a continuous left-lateral movement of the Pernicana Fault. We conclude that, on the easternmost part of the Pernicana Fault, where it branches out into two segments, the deformation is transferred entirely SE-wards by a splay fault

    SuperB Progress Report for Physics

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    SuperB is a high luminosity e{sup +}e{sup -} collider that will be able to indirectly probe new physics at energy scales far beyond the reach of any man made accelerator planned or in existence. Just as detailed understanding of the Standard Model of particle physics was developed from stringent constraints imposed by flavour changing processes between quarks, the detailed structure of any new physics is severely constrained by flavour processes. In order to elucidate this structure it is necessary to perform a number of complementary studies of a set of golden channels. With these measurements in hand, the pattern of deviations from the Standard Model behavior can be used as a test of the structure of new physics. If new physics is found at the LHC, then the many golden measurements from SuperB will help decode the subtle nature of the new physics. However if no new particles are found at the LHC, SuperB will be able to search for new physics at energy scales up to 10-100 TeV. In either scenario, flavour physics measurements that can be made at SuperB play a pivotal role in understanding the nature of physics beyond the Standard Model. Examples for using the interplay between measurements to discriminate New Physics models are discussed in this document. SuperB is a Super Flavour Factory, in addition to studying large samples of B{sub u,d,s}, D and {tau} decays, SuperB has a broad physics programme that includes spectroscopy both in terms of the Standard Model and exotica, and precision measurements of sin{sup 2} {theta}{sub W}. In addition to performing CP violation measurements at the {Upsilon}(4S) and {phi}(3770), SuperB will test CPT in these systems, and lepton universality in a number of different processes. The multitude of rare decay measurements possible at SuperB can be used to constrain scenarios of physics beyond the Standard Model. In terms of other precision tests of the Standard Model, this experiment will be able to perform precision over-constraints of the unitarity triangle through multiple measurements of all angles and sides. This report extends and updates the studies presented in both the SuperB Conceptual Design Report in 2007 and the Proceedings of SuperB Workshop VI in Valencia in 2008. Together, these three documents detail the Physics case of the SuperB Project

    Study of the reaction pbar p -> phi phi from 1.1 to 2.0 GeV/c

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    A study has been performed of the reaction pbar p -> 4K using in-flight antiprotons from 1.1 to 2.0 GeV/c incident momentum interacting with a hydrogen jet target. The reaction is dominated by the production of a pair of phi mesons. The pbar p -> phi phi cross section rises sharply above threshold and then falls continuously as a function of increasing antiproton momentum. The overall magnitude of the cross section exceeds expectations from a simple application of the OZI rule by two orders of magnitude. In a fine scan around the xi/f_J(2230) resonance, no structure is observed. A limit is set for the double branching ratio B(xi -> pbar p) * B(xi -> phi phi) < 6e-5 for a spin 2 resonance of M = 2.235 GeV and Width = 15 MeV.Comment: 13 pages, 13 figures, 2 tables, Latex. To be published in Phys. Rev.
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