77 research outputs found

    Reconnaissance à la volée de documents structurés manuscrits en-ligne

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    Dans ce papier, une nouvelle approche pour l'interprétation de documents structurés manuscrits en-ligne est présentée. Elle est basée sur un formalisme flexible et générique permettant la reconnaissance à la volée des éléments d'un document structuré. L'originalité du formalisme est la modélisation du couplage d'une vision globale du document analysé avec une vision locale de l'élément à reconnaßtre. L'analyseur pilote alors des reconnaisseurs de formes dédiés en fonction du contexte structurel de l'élément analysé. Nous détaillons plus particuliÚrement le processus de prise de décision en cas d'ambiguïté entre plusieurs interprétations possibles. Nous exploitons la théorie des sous-ensembles flous afin de prendre en compte la nature imprécise du tracé manuscrit et des contextes structurels modélisés. Cette approche a été validée avec le développement de trois systÚmes orientés stylo : pour l'édition de partitions musicales, de graphes et de diagrammes de classes UML

    Explicit fuzzy modeling of shapes and positioning for handwritten Chinese character recognition

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    International audienceIn this paper, we present a new method for on-line Chinese character recognition that relies on an explicit description of characters structure. Contrary to most of known structural approaches, this model can describe characters written in a fluent style, thanks to a flexible fuzzy modeling of shapes and positioning of their structural components (primitives and radicals). We designed a process for incremental training of the models cooperated with automatic structural labeling for minimizing the required manual task in model design. First experiments show that the method is able to recognize non-regularly written characters and has a convincing generalization ability

    Fuzzy Relative Positioning for On-Line Handwritten Stroke Analysis

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    http://www.suvisoft.comThis paper deals with the qualitative and robust modelling of the relative positioning of on-line handwritten strokes. We exploit the fuzzy approach to take the imprecision of such relations into account. We first transpose a well-formalized method which proved itself in the domain of image analysis to the on-line case; it aims at evaluating the relation “to be in a given direction” relatively to a reference. Our first contribution is a solution to deal with the particular nature of on-line strokes, which are constituted of non-connected points. Our second and main contribution is a method to learn automatically fuzzy relative position relationships. It aims at evaluating the relation “to be in a given position” relatively to a reference using jointly the direction and the distance. We test the impact of this new fuzzy positioning approach on one possible application: the recognition of handwritten graphic gestures, which requires spatial context information to be discriminated. Whereas the recognition rate is 52.95% without any spatial information, we obtain a maximum of 95.75% when we use learnt relative position relationships

    Extraction des piĂšces d'un plan d'habitation

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    International audienceIn this article, a method to extract the rooms of an architectural floor plan image is described. We first present a line detection algorithm to extract long lines in the image. Those lines are analyzed to identify the existing walls. From this point, room extraction can be seen as a classical segmentation task for which each region corresponds to a room. The chosen resolution strategy consists in recursively decomposing the image until getting nearly convex regions. The notion of convexity is difficult to quantify, and the selection of separation lines can also be rough. Thus, we take advantage of knowledge associated to architectural floor plans in order to obtain mainly rectangular rooms. Preliminary tests on a set of real documents show promising results.Dans cet article, une mĂ©thodologie d'extraction des piĂšces d'une image de plan architectural est dĂ©crite. Nous prĂ©sentons tout d'abord un algorithme de dĂ©tection des lignes de l'image. Ces lignes sont analysĂ©es afin d'identifier les murs constituant le plan. L'extraction des piĂšces peut ensuite ĂȘtre apparentĂ©e Ă  un problĂšme de segmentation pour lequel chaque rĂ©gion correspond Ă  une piĂšce. Dans ce contexte, le processus de rĂ©solution consiste Ă  dĂ©composer rĂ©cursivement l'image jusqu'Ă  l'obtention de rĂ©gions quasi convexes. De mĂȘme que la notion de convexitĂ© est difficilement quantifiable, le choix d'un dĂ©coupage est Ă©galement approximatif. DĂšs lors, nous prenons en compte des connaissances associĂ©es aux plans architecturaux, afin notamment d'obtenir un ensemble de piĂšces majoritairement rectangulaires. De premiĂšres expĂ©rimentations sur un corpus de documents rĂ©els illustrent la pertinence de l'approche

    Produire des contenus documentaires en ligne

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    Les bibliothĂšques sont confrontĂ©es Ă  des nĂ©cessitĂ©s d’exploitation de leurs collections qui ne passent plus seulement par la gestion du stock mais par l’appropriation et la restitution de contenus documentaires. Le plan de l’ouvrage s’articule autour de quatre parties : exploiter les collections ; la curation et la production de contenus ; produire en rĂ©seau, et enfin, connaĂźtre le contexte juridique et Ă©crire pour le web. Ainsi, le professionnel est devenu mĂ©diateur, producteur et Ă©diteur de matiĂšres documentaires Ă©laborĂ©es. Chaque partie traite aussi des nouvelles compĂ©tences relationnelles et techniques Ă  acquĂ©rir pour ce faire. Une quinzaine de professionnels abordent ces diffĂ©rents aspects, en s’appuyant sur des rĂ©alisations concrĂštes menĂ©es dans les bibliothĂšques, de lecture publique comme des universitĂ©s

    Model-based geostatistical mapping of the prevalence of onchocerca volvulus in West Africa.

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    Background: The initial endemicity (pre-control prevalence) of onchocerciasis has been shown to be an important determinant of the feasibility of elimination by mass ivermectin distribution. We present the first geostatistical map of microfilarial prevalence in the former Onchocerciasis Control Programme in West Africa (OCP) before commencement of antivectorial and antiparasitic interventions. Methods and Findings: Pre-control microfilarial prevalence data from 737 villages across the 11 constituent countries in the OCP epidemiological database were used as ground-truth data. These 737 data points, plus a set of statistically selected environmental covariates, were used in a Bayesian model-based geostatistical (B-MBG) approach to generate a continuous surface (at pixel resolution of 5 km x 5km) of microfilarial prevalence in West Africa prior to the commencement of the OCP. Uncertainty in model predictions was measured using a suite of validation statistics, performed on bootstrap samples of held-out validation data. The mean Pearson’s correlation between observed and estimated prevalence at validation locations was 0.693; the mean prediction error (average difference between observed and estimated values) was 0.77%, and the mean absolute prediction error (average magnitude of difference between observed and estimated values) was 12.2%. Within OCP boundaries, 17.8 million people were deemed to have been at risk, 7.55 million to have been infected, and mean microfilarial prevalence to have been 45% (range: 2–90%) in 1975. Conclusions and Significance: This is the first map of initial onchocerciasis prevalence in West Africa using B-MBG. Important environmental predictors of infection prevalence were identified and used in a model out-performing those without spatial random effects or environmental covariates. Results may be compared with recent epidemiological mapping efforts to find areas of persisting transmission. These methods may be extended to areas where data are sparse, and may be used to help inform the feasibility of elimination with current and novel tools

    Defining the Effect of the 16p11.2 Duplication on Cognition, Behavior, and Medical Comorbidities

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    IMPORTANCE The 16p11.2 BP4-BP5 duplication is the copy number variant most frequently associated with autism spectrum disorder (ASD), schizophrenia, and comorbidities such as decreased body mass index (BMI). OBJECTIVES To characterize the effects of the 16p11.2 duplication on cognitive, behavioral, medical, and anthropometric traits and to understand the specificity of these effects by systematically comparing results in duplication carriers and reciprocal deletion carriers, who are also at risk for ASD. DESIGN, SETTING, AND PARTICIPANTS This international cohort study of 1006 study participants compared 270 duplication carriers with their 102 intrafamilial control individuals, 390 reciprocal deletion carriers, and 244 deletion controls from European and North American cohorts. Data were collected from August 1, 2010, to May 31, 2015 and analyzed from January 1 to August 14, 2015. Linear mixed models were used to estimate the effect of the duplication and deletion on clinical traits by comparison with noncarrier relatives. MAIN OUTCOMES AND MEASURES Findings on the Full-Scale IQ (FSIQ), Nonverbal IQ, and Verbal IQ; the presence of ASD or other DSM-IV diagnoses; BMI; head circumference; and medical data. RESULTS Among the 1006 study participants, the duplication was associated with a mean FSIQ score that was lower by 26.3 points between proband carriers and noncarrier relatives and a lower mean FSIQ score (16.2-11.4 points) in nonproband carriers. The mean overall effect of the deletion was similar (-22.1 points; P 100) compared with the deletion group (P < .001). Parental FSIQ predicted part of this variation (approximately 36.0% in hereditary probands). Although the frequency of ASD was similar in deletion and duplication proband carriers (16.0% and 20.0%, respectively), the FSIQ was significantly lower (by 26.3 points) in the duplication probands with ASD. There also were lower head circumference and BMI measurements among duplication carriers, which is consistent with the findings of previous studies. CONCLUSIONS AND RELEVANCE The mean effect of the duplication on cognition is similar to that of the reciprocal deletion, but the variance in the duplication is significantly higher, with severe and mild subgroups not observed with the deletion. These results suggest that additional genetic and familial factors contribute to this variability. Additional studies will be necessary to characterize the predictors of cognitive deficits

    CNV-association meta-analysis in 191,161 European adults reveals new loci associated with anthropometric traits

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    Funding Information: This research has been conducted using the UK Biobank Resource. This research has been conducted using the Danish National Biobank resource. The authors are grateful to the Raine Study participants and their families, and to the Raine Study research staff for cohort co-ordination and data collection. QIMR is grateful to the twins and their families for their generous participation in these studies. We would like to thank staff at the Queensland Institute of Medical Research: Anjali Henders, Dixie Statham, Lisa Bowdler, Ann Eldridge, and Marlene Grace for sample collection, processing and genotyping, Scott Gordon, Brian McEvoy, Belinda Cornes and Beben Benyamin for data QC and preparation, and David Smyth and Harry Beeby for IT support. HBCS Acknowledgements: We thank all study participants as well as everybody involved in the Helsinki Birth Cohort Study. Helsinki Birth Cohort Study has been supported by grants from the Academy of Finland, the Finnish Diabetes Research Society, FolkhÀlsan Research Foundation, Novo Nordisk Foundation, Finska LÀkaresÀllskapet, Juho Vainio Foundation, Signe and Ane Gyllenberg Foundation, University of Helsinki, Ministry of Education, Ahokas Foundation, Emil Aaltonen Foundation. Finrisk study is grateful for the THL DNA laboratory for its skillful work to produce the DNA samples used in this study and thanks the Sanger Institute and FIMM genotyping facilities for genotyping the samples. We thank the MOLGENIS team and Genomics Coordination Center of the University Medical Center Groningen for software development and data management, in particular Marieke Bijlsma and Edith Adriaanse. This work was supported by the Leenards Foundation (to Z.K.), the Swiss National Science Foundation (31003A_169929 to Z.K., Sinergia grant CRSII33-133044 to AR), Simons Foundation (SFARI274424 to AR) and SystemsX.ch (51RTP0_151019 to Z.K.). A.R.W., H.Y. and T.M.F. are supported by the European Research Council grant: 323195:SZ-245. M.A.T., M.N.W. and An.M. are supported by the Wellcome Trust Institutional Strategic Support Award (WT097835MF). For full funding information of all participating cohorts see Supplementary Note 2. Publisher Copyright: © 2017 The Author(s).There are few examples of robust associations between rare copy number variants (CNVs) and complex continuous human traits. Here we present a large-scale CNV association meta-analysis on anthropometric traits in up to 191,161 adult samples from 26 cohorts. The study reveals five CNV associations at 1q21.1, 3q29, 7q11.23, 11p14.2, and 18q21.32 and confirms two known loci at 16p11.2 and 22q11.21, implicating at least one anthropometric trait. The discovered CNVs are recurrent and rare (0.01-0.2%), with large effects on height (> 2.4 cm), weight ( 5 kg), and body mass index (BMI) (> 3.5 kg/m(2)). Burden analysis shows a 0.41 cm decrease in height, a 0.003 increase in waist-to-hip ratio and increase in BMI by 0.14 kg/m2 for each Mb of total deletion burden (P = 2.5 x 10(-10), 6.0 x 10(-5), and 2.9 x 10(-3)). Our study provides evidence that the same genes (e.g., MC4R, FIBIN, and FMO5) harbor both common and rare variants affecting body size and that anthropometric traits share genetic loci with developmental and psychiatric disorders.Peer reviewe

    ModĂ©lisation du fonctionnement d’un gyrolaser He-Ne de trĂšs haute prĂ©cision

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    Ring laser gyros (RLG) are inertial sensors whose reliability and accuracy have been recognised since the mid-1980s. Their high sensitivity enables them to measure angular velocity with an accuracy of 10⁻³ °/ h in aeronautics. However, because of a complex functioning based on a rich and varied physics, their performances are highly dependent on the working conditions and on any modification in the manufacturing process. In this case, a numerical modelling is pertinent since it allows both a clear understanding of the ring laser physics and parametric studies which are not experimentally feasible. The global modelling of a He-Ne RLG has been the main objective of the collaboration between Sagem (Safran group), which is one of the world leader in the inertial sensors field, and the Gas and Plasma Physics Laboratory (LPGP).This modelling is “multi-physics” since RLG physics involves several disciplines (plasma, atomic and laser physics). Therefore we have developed three models specifically adapted to each field. The first one describes the modelling of the positive column of the glow discharge following a fluid approach. This model allows a quantitative description of the plasma and gives access to fundamental quantities like the electron density or the electron energy distribution function. These quantities are the required inputs for the second model which treats the kinetics of the excited states inside the He-Ne plasma. For this, a collisional-radiative model in a radial geometry (1D-CRM) has been developed. The radial geometry is justified by the importance of the transport processes of atoms and radiations which can influence the radial profile of the population inversion. Notably, the radiative transfer by self-absorption of the resonant radiative transitions has been modelled by solving the Holstein-Biberman equation by a Monte-Carlo method. This aspect is a major component of this PhD work. Diffusion of excited atoms inside the plasma has also been taken into account by solving the diffusion equation with different boundary conditions at the capillary surface. From the populations and the kinetic rates computed by 1D-CRM, the laser amplification inside the cavity has been modelled using a two-level Maxwell-Bloch approach (NADIA) taking into account the inhomogeneous gain saturation, which means to consider the thermal speed of the atoms in the direction of propagation of the laser beams. The kinetics of NADIA has been optimized and transport processes in the phase space have also been implemented. This model has been used to study the performances of the RLG linked to the amplifying medium and to derive the physical parameters needed for the development of a simulator.Concerning this simulator, a simplified physical model from NADIA has been coupled to system modules in order to reproduce the operating signal of a RLG. This allows to conduct parametric studies on the quantities defining the RLG performance in particular the dynamic bias and the so-called “Random Walk”. We showed notably that the results of our simulator are in good agreement with experimental measurements in operating conditions. Moreover, our results show that this simulator is a powerful tool for analysing experimental data.Les gyromĂštres laser He-Ne sont des senseurs inertiels dont la fiabilitĂ© et la prĂ©cision sont reconnues depuis le milieu des annĂ©es 1980. Leur grande sensibilitĂ© leur permet de mesurer des vitesses de rotation avec une prĂ©cision qui atteint 10⁻³ °/ h dans le domaine aĂ©ronautique. Cependant, du fait d’un fonctionnement complexe basĂ© sur une physique riche et variĂ©e, ses performances sont fortement dĂ©pendantes des conditions de fonctionnement et de toute modification du processus de fabrication. Dans ce cas, un travail de modĂ©lisation prend tout son sens, puisqu’il permet, outre une comprĂ©hension claire et prĂ©cise des diffĂ©rents phĂ©nomĂšnes physiques, un accĂšs Ă  des Ă©tudes paramĂ©triques non envisageables expĂ©rimentalement. La modĂ©lisation globale du fonctionnement d’un gyrolaser He-Ne a ainsi Ă©tĂ© l’objectif principal de la collaboration entre la sociĂ©tĂ© Sagem (groupe Safran), un des leaders mondiaux dans le domaine des senseurs inertiels, et le Laboratoire de Physique des Gaz et des Plasmas (LPGP). Cette modĂ©lisation est « multiphysique » du fait de la diversitĂ© des domaines que couvre la physique du gyrolaser (Plasma, Physique Atomique, Lasers). C’est pourquoi nous avons dĂ©veloppĂ© trois modĂšles spĂ©cifiquement adaptĂ©s Ă  chaque domaine. Le premier dĂ©crit la modĂ©lisation de la colonne positive du plasma de dĂ©charge dans une approche fluide. Ce modĂšle permet une description quantitative du plasma et l’accĂšs aux grandeurs telles que la densitĂ© Ă©lectronique et la fonction de distribution en Ă©nergie des Ă©lectrons. Ces grandeurs sont les entrĂ©es nĂ©cessaires au second modĂšle qui traite la cinĂ©tique des Ă©tats excitĂ©s du plasma He-Ne. Un modĂšle collisionnel-radiatif Ă  1 dimension radiale (1D-CRM) a ainsi Ă©tĂ© dĂ©veloppĂ©. L’aspect 1D se justifie par l’importance des phĂ©nomĂšnes de transport d’atomes et de rayonnement pouvant influer sur le profil radial de l’inversion de population du laser. Le transfert radiatif par auto-absorption des transitions radiatives rĂ©sonantes a notamment Ă©tĂ© modĂ©lisĂ© en rĂ©solvant l’équation de Holstein-Biberman Ă  partir d’une mĂ©thode Monte-Carlo. Cet aspect constitue un Ă©lĂ©ment majeur de ce travail de thĂšse. La diffusion des atomes excitĂ©s du mĂ©lange He-Ne a Ă©galement Ă©tĂ© prise en compte en rĂ©solvant l’équation de diffusion avec diffĂ©rentes conditions au bord Ă  la surface du capillaire.A partir des populations et des taux cinĂ©tiques de peuplement et dĂ©peuplement calculĂ©s par 1D-CRM, l’amplification laser dans la cavitĂ© a Ă©tĂ© modĂ©lisĂ©e dans le cadre d’une approche Maxwell-Bloch Ă  2 niveaux (NADIA) en incluant la saturation inhomogĂšne du gain c’est-Ă -dire en tenant compte de la vitesse des atomes Ă©metteurs dans la direction de propagation des faisceaux lasers. La cinĂ©tique de NADIA a Ă©tĂ© optimisĂ©e et les processus de transports dans l’espace des phases ont Ă©galement Ă©tĂ© implĂ©mentĂ©s. Ce modĂšle a Ă©tĂ© utilisĂ© pour Ă©tudier les performances du gyrolaser liĂ©es au milieu amplificateur et pour dĂ©river les paramĂštres physiques nĂ©cessaires au dĂ©veloppement d’un simulateur du gyrolaser.Dans ce simulateur, un modĂšle physique simplifiĂ© dĂ©rivĂ© de NADIA, a Ă©tĂ© couplĂ© Ă  des modules « systĂšmes » dans le but de reproduire en sortie le signal opĂ©rationnel d’un gyrolaser. Ceci nous a permis de rĂ©aliser des Ă©tudes paramĂ©triques sur les grandeurs caractĂ©risant les performances d’un gyrolaser notamment le biais dynamique et le Random-Walk. Nous montrons en particulier que les performances de notre simulateur sont en bon accord avec celles observĂ©es en conditions opĂ©rationnelles. De plus, nos rĂ©sultats montrent que ce simulateur est Ă©galement un outil puissant pour l’analyse de donnĂ©es expĂ©rimentales

    Modelling the operation of a very high precision He-Ne ring laser gyro

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    Les gyromĂštres laser He-Ne sont des senseurs inertiels dont la fiabilitĂ© et la prĂ©cision sont reconnues depuis le milieu des annĂ©es 1980. Leur grande sensibilitĂ© leur permet de mesurer des vitesses de rotation avec une prĂ©cision qui atteint 10⁻³ °/ h dans le domaine aĂ©ronautique. Cependant, du fait d’un fonctionnement complexe basĂ© sur une physique riche et variĂ©e, ses performances sont fortement dĂ©pendantes des conditions de fonctionnement et de toute modification du processus de fabrication. Dans ce cas, un travail de modĂ©lisation prend tout son sens, puisqu’il permet, outre une comprĂ©hension claire et prĂ©cise des diffĂ©rents phĂ©nomĂšnes physiques, un accĂšs Ă  des Ă©tudes paramĂ©triques non envisageables expĂ©rimentalement. La modĂ©lisation globale du fonctionnement d’un gyrolaser He-Ne a ainsi Ă©tĂ© l’objectif principal de la collaboration entre la sociĂ©tĂ© Sagem (groupe Safran), un des leaders mondiaux dans le domaine des senseurs inertiels, et le Laboratoire de Physique des Gaz et des Plasmas (LPGP). Cette modĂ©lisation est « multiphysique » du fait de la diversitĂ© des domaines que couvre la physique du gyrolaser (Plasma, Physique Atomique, Lasers). C’est pourquoi nous avons dĂ©veloppĂ© trois modĂšles spĂ©cifiquement adaptĂ©s Ă  chaque domaine. Le premier dĂ©crit la modĂ©lisation de la colonne positive du plasma de dĂ©charge dans une approche fluide. Ce modĂšle permet une description quantitative du plasma et l’accĂšs aux grandeurs telles que la densitĂ© Ă©lectronique et la fonction de distribution en Ă©nergie des Ă©lectrons. Ces grandeurs sont les entrĂ©es nĂ©cessaires au second modĂšle qui traite la cinĂ©tique des Ă©tats excitĂ©s du plasma He-Ne. Un modĂšle collisionnel-radiatif Ă  1 dimension radiale (1D-CRM) a ainsi Ă©tĂ© dĂ©veloppĂ©. L’aspect 1D se justifie par l’importance des phĂ©nomĂšnes de transport d’atomes et de rayonnement pouvant influer sur le profil radial de l’inversion de population du laser. Le transfert radiatif par auto-absorption des transitions radiatives rĂ©sonantes a notamment Ă©tĂ© modĂ©lisĂ© en rĂ©solvant l’équation de Holstein-Biberman Ă  partir d’une mĂ©thode Monte-Carlo. Cet aspect constitue un Ă©lĂ©ment majeur de ce travail de thĂšse. La diffusion des atomes excitĂ©s du mĂ©lange He-Ne a Ă©galement Ă©tĂ© prise en compte en rĂ©solvant l’équation de diffusion avec diffĂ©rentes conditions au bord Ă  la surface du capillaire.A partir des populations et des taux cinĂ©tiques de peuplement et dĂ©peuplement calculĂ©s par 1D-CRM, l’amplification laser dans la cavitĂ© a Ă©tĂ© modĂ©lisĂ©e dans le cadre d’une approche Maxwell-Bloch Ă  2 niveaux (NADIA) en incluant la saturation inhomogĂšne du gain c’est-Ă -dire en tenant compte de la vitesse des atomes Ă©metteurs dans la direction de propagation des faisceaux lasers. La cinĂ©tique de NADIA a Ă©tĂ© optimisĂ©e et les processus de transports dans l’espace des phases ont Ă©galement Ă©tĂ© implĂ©mentĂ©s. Ce modĂšle a Ă©tĂ© utilisĂ© pour Ă©tudier les performances du gyrolaser liĂ©es au milieu amplificateur et pour dĂ©river les paramĂštres physiques nĂ©cessaires au dĂ©veloppement d’un simulateur du gyrolaser.Dans ce simulateur, un modĂšle physique simplifiĂ© dĂ©rivĂ© de NADIA, a Ă©tĂ© couplĂ© Ă  des modules « systĂšmes » dans le but de reproduire en sortie le signal opĂ©rationnel d’un gyrolaser. Ceci nous a permis de rĂ©aliser des Ă©tudes paramĂ©triques sur les grandeurs caractĂ©risant les performances d’un gyrolaser notamment le biais dynamique et le Random-Walk. Nous montrons en particulier que les performances de notre simulateur sont en bon accord avec celles observĂ©es en conditions opĂ©rationnelles. De plus, nos rĂ©sultats montrent que ce simulateur est Ă©galement un outil puissant pour l’analyse de donnĂ©es expĂ©rimentales.Ring laser gyros (RLG) are inertial sensors whose reliability and accuracy have been recognised since the mid-1980s. Their high sensitivity enables them to measure angular velocity with an accuracy of 10⁻³ °/ h in aeronautics. However, because of a complex functioning based on a rich and varied physics, their performances are highly dependent on the working conditions and on any modification in the manufacturing process. In this case, a numerical modelling is pertinent since it allows both a clear understanding of the ring laser physics and parametric studies which are not experimentally feasible. The global modelling of a He-Ne RLG has been the main objective of the collaboration between Sagem (Safran group), which is one of the world leader in the inertial sensors field, and the Gas and Plasma Physics Laboratory (LPGP).This modelling is “multi-physics” since RLG physics involves several disciplines (plasma, atomic and laser physics). Therefore we have developed three models specifically adapted to each field. The first one describes the modelling of the positive column of the glow discharge following a fluid approach. This model allows a quantitative description of the plasma and gives access to fundamental quantities like the electron density or the electron energy distribution function. These quantities are the required inputs for the second model which treats the kinetics of the excited states inside the He-Ne plasma. For this, a collisional-radiative model in a radial geometry (1D-CRM) has been developed. The radial geometry is justified by the importance of the transport processes of atoms and radiations which can influence the radial profile of the population inversion. Notably, the radiative transfer by self-absorption of the resonant radiative transitions has been modelled by solving the Holstein-Biberman equation by a Monte-Carlo method. This aspect is a major component of this PhD work. Diffusion of excited atoms inside the plasma has also been taken into account by solving the diffusion equation with different boundary conditions at the capillary surface. From the populations and the kinetic rates computed by 1D-CRM, the laser amplification inside the cavity has been modelled using a two-level Maxwell-Bloch approach (NADIA) taking into account the inhomogeneous gain saturation, which means to consider the thermal speed of the atoms in the direction of propagation of the laser beams. The kinetics of NADIA has been optimized and transport processes in the phase space have also been implemented. This model has been used to study the performances of the RLG linked to the amplifying medium and to derive the physical parameters needed for the development of a simulator.Concerning this simulator, a simplified physical model from NADIA has been coupled to system modules in order to reproduce the operating signal of a RLG. This allows to conduct parametric studies on the quantities defining the RLG performance in particular the dynamic bias and the so-called “Random Walk”. We showed notably that the results of our simulator are in good agreement with experimental measurements in operating conditions. Moreover, our results show that this simulator is a powerful tool for analysing experimental data
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