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  • English
    Authors: 
    Khellaf, Feriel; Krah, Nils; Rinaldi, Ilaria; Létang, Jean Michel; Rit, Simon;
    Publisher: HAL CCSD
    Country: France

    International audience

  • French
    Authors: 
    Trocherie, F.; Bray, M.; Garric, Jeanne;
    Publisher: HAL CCSD

    La réalisation de tests de toxicité portant sur des organismes vivants est nécessaire pour l'évaluation des risques liés à la diffusion de nouveaux produits dans l'environnement. Ces tests sont généralement lourds à mettre en oeuvre et doivent donc n'être utilisés qu'à bon escient, en programmant à chaque étape des expériences tenant compte de l'ensemble des données physicochimiques relatives aux produits étudiés et des résultats des essais effectués aux étapes précédentes. Les auteurs, à partir de leur propre expérience et d'une synthèse bibliographique, exposent les principes qui peuvent présider à une telle démarche et discutent des méthodes statistiques qui permettent de valoriser au mieux l'information recueillie.

  • Publication . Preprint . Conference object . Article . Other literature type . 2003
    Open Access English
    Authors: 
    Berestycki, Nathanael; Durrett, Rick;
    Publisher: HAL CCSD
    Country: France

    Our work is motivated by Bourque and Pevzner's (2002) simulation study of the effectiveness of the parsimony method in studying genome rearrangement, and leads to a surprising result about the random transposition walk on the group of permutations on $n$ elements. Consider this walk in continuous time starting at the identity and let $D_t$ be the minimum number of transpositions needed to go back to the identity from the location at time $t$. $D_t$ undergoes a phase transition: the distance $D_{cn/2} \sim u(c)n$, where $u$ is an explicit function satisfying $u(c)=c/2$ for $c \le 1$ and $u(c)1$. In other words, the distance to the identity is roughly linear during the subcritical phase, and after critical time $n/2$ it becomes sublinear. In addition, we describe the fluctuations of $D_{cn/2}$ about its mean in each of the threeregimes (subcritical, critical and supercritical). The techniques used involve viewing the cycles in the random permutation as a coagulation-fragmentation process and relating the behavior to the \Erd\H{o}s-Renyi random graph model. Comment: Revisions include considerable changes in the presentation of section 6 (proof of the CLT in the supercritical regime), and several typos corrected. Also, the figures are now available as a separate .ps file

  • English
    Authors: 
    Yu Lu; Claire Le Paven; Hung Viet Nguyen; Ratiba Benzerga; Laurent Le Gendre; Stéphane Rioual; Franck Tessier; François Cheviré; Ala Sharaiha; Christophe Delaveaud; +1 more
    Publisher: HAL CCSD
    Country: France

    International audience; Perovskite lanthanum titanium thin films were deposited on Nb-doped (001) SrTiO3 substrates by reactive RF magnetron sputtering using a La2Ti2O7 target. Oxynitride LaTiO2N films were obtained using N2 rich plasma; they display a variation of their dielectric constant as a function of DC bias in the low frequency range but not in microwaves. The dielectric constant (epsilon) values are high with, for example, epsilon = 325 at 100 kHz. The oxide films, obtained in O2 rich plasma, are composed of an unusual La2Ti2O7 phase with an orthorhombic cell. The films are (101) epitaxied on Nb:SrTiO3 substrates. The dielectric constant value of films is around 77 with losses 0.076 at 100 kHz; no agility of epsilon in low and high frequencies is detected. Composite and bilayer films, with oxynitride and oxide phases, exhibit a variation of epsilon under DC bias in low frequencies with, for example, an agility of 15% at 100 kHz with a maximum applied field of 40 kV/cm for the LaTiO2N (200 nm)/La2Ti2O7 (250 nm) bilayer.

  • Publication . Conference object . 2020
    English
    Authors: 
    Privat, Jean-Marie;
    Publisher: HAL CCSD
    Country: France

    International audience

  • English
    Authors: 
    Hee Ryung Lee; Christian Lotz; Florian Groeber-Becker; Sofia Dembski; Enric Garcia-Caurel; Razvigor Ossikovski; Tatiana Novikova;
    Publisher: HAL CCSD
    Country: France

    Mueller transmission microscopy has been used for both theoretical and experimental studies of anisotropic scattering biological tissue. In our prior study, the linear dependence of retardance and quadratic dependence of depolarization on thickness was demonstrated for a dermal layer of skin model. During the primary analysis of polarimetric images of histological cuts both epidermal and dermal layers were delineated manually in order to calculate the spatially averaged values of retardance and depolarization parameters. Consequently, these average values contained the contribution of outliers (noise, not correctly identified pixels, etc.) which produces large standard deviation and biased mean values of the parameters mentioned above. For preventing the errors, the normalized maps of optical properties were calculated pixel-wise taking into account local optical density (e. i. logarithm of M11 element of Mueller matrix at each image pixel) to compensate varying tissue thickness across the cut area. Furthermore, the DBSCAN (Density-based spatial clustering of applications with noise) algorithm was applied for segmentation of microscopic images using the normalized values of retardance, depolarization, and intensity. From the results of image segmentation, we could discriminate the regions of dermal and epidermal layers in Muller microscopic images of skin cuts more accurately and obtain more reliable values of tissue’s optical properties.

  • English
    Authors: 
    Freund, Frédérique; Muller, Catherine;
    Publisher: HAL CCSD

    International audience; Understanding teachers’ rationale and strategies for implementing CALL in their practices is of critical importance in teacher education research, especially with a view to designing teacher training programs that address real-life issues faced by practitioners and that help develop both a reflective and a pragmatic approach to the integration of technology in the language learning classroom (Egbert & Petrie, 2005; Stockwell, 2009; Guichon & Hauck, 2011).The present contribution proposes to explore an in-service teacher’s own perspective on her technology-mediated practice in the specific context of a blended EFL course, which combines face-to-face group instruction in a computer lab with individualized, self-paced instruction within an LMS.It aims at assessing what motives inform the teacher’s actions in such a context, with a focus on what she perceives her mediating role may be, both in managing the relationship between the different spaces that she and the learners inhabit (in class and online), and in developing learners’ autonomy (Borg & Al-Busaidi, 2012).The blended EFL course presented in this in-depth case study is an English course for Master’s students in history at a French university which focuses on the acquisition of English speaking skills. In addition to field observation, video stimulated recall was used to provide access to the teacher’s perceptions (Lazarton, & Ishihara, 2005). Data is interpreted using a qualitative, inductive approach.The analysis of the teacher’s discourse provides insight into what successful integration of CALL in a blended learning environment entails from the practitioner’s perspective and what role she should play in a learner-centred approach, especially in ensuring the human aspect of the pedagogical relationship is preserved.As a conclusion, we propose to briefly discuss the potential of using video-stimulated recall as a self-confrontation method, both for the professional development of pre- and in-service teachers and for fostering interaction between research and practice.

  • Publication . Conference object . Part of book or chapter of book . 2016
    English
    Authors: 
    Sanseverino-Godfrin, Valérie;
    Publisher: HAL CCSD
    Country: France

    International audience; Recently, regarding the explosion of AZF, she French Supreme administrative court, the State Council (Conseil d’Etat) estimated that the state department charged with the inspection of the industrial activities (DREAL – Direction Régional de l’Environnement, de l’Aménagement et du Logement) did not commit any negligence in the inspection of the plant and had no part of the responsibility in the accident. The judges based their decision on the fact that in the safety report, elaborated in 1990 by the industrial, the danger of the explosion of the ammonium nitrate warehouse was not considered. Moreover, nobody informed the state department of the lack of compliance of the industrial activity with the legal measures and so, of the lack of safety. However, the judicial inquiry lead following the accident had demonstrated serious negligence in the management of the site, which had never been the subject of a report by the DREAL, despite eleven inspection visits within the last six years before the explosion. The State Council has confirmed a certain conception of the inspection of the industrial plants: inspection appears as one of the modes of the regulation in the environmental and safety field, with an evolution of the role of the State and the industrial.

  • Authors: 
    W. Aouimeur; Sylvie Lepilliet; Christophe Gaquiere; Estelle Lauga-Larroze; Jean-Daniel Arnould; J. Moron-Guerra; Thomas Quemerais; Daniel Gloria; Ayssar Serhan;
    Publisher: IEEE
    Country: France

    International audience; This paper describes an in-situ reflectometer for one port VNA in 160 to 200 GHz band (G Band). The proposed system is fabricated in 55 nm SiGe BiCMOS technology from STMicroelectronics. Measured performances of system shown 110 mW of power DC consumption from a 1.2 V supply. A 180 GHz nMOS is measured as the device-under-test (DUT) after an in-situ calibration. The results obtained using this fully integrated VNA have been compared to a commercial VNA. A discrepancy of 0.3 dB is noted between the two systems on magnitude over a wide frequency range 172-192 GHz. Without calibration, the “raw” dynamics range of the system is limited by the directivity of the coupler which is 20 dB at 140-220 GHz. This dynamic will be improved after the calibration. The SiGe chip size is 3.3 mm2 . To our best knowledge, the presented in-situ VNA have the first results compared to the recently published and are the first with an in-situ calibration integrated in SiGe or CMOS technologies.

  • Publication . Part of book or chapter of book . 2015
    Open Access English
    Authors: 
    Milad Ashour Pour; Massimo Zanardini; Andrea Bacchetti; Simone Zanoni;
    Publisher: HAL CCSD
    Country: Italy

    Part 4: The Role of Additive Manufacturing in Value Chain Reconfigurations and Sustainability; International audience; With an ever growing diffusion of Additive Manufacturing (AM) system in industrial and commercial level, as well as the direct and indirect dynamics which are being introduced resulting from its inclusion as a possible production technology on companies’ portfolio, the need to reconfigure production system and adapt the production strategy becomes even more relevant than before. There are several studies which have emphasized on the importance of a paradigm shift in order to exploit advantages of AM, not only considering changes within design and functionality of the product, but also concerning AM’s impact on the entire value chain (re)configuration. Thus, it is of crucial importance to take into consideration that for this shift to be feasible and manageable, there is a need to include both technical and managerial aspects of manufacturing. This work proposes an economic insight in order to provide a guideline for the proper evaluation of AM system implementation.

search
Include:
778,867 Research products, page 1 of 77,887
  • English
    Authors: 
    Khellaf, Feriel; Krah, Nils; Rinaldi, Ilaria; Létang, Jean Michel; Rit, Simon;
    Publisher: HAL CCSD
    Country: France

    International audience

  • French
    Authors: 
    Trocherie, F.; Bray, M.; Garric, Jeanne;
    Publisher: HAL CCSD

    La réalisation de tests de toxicité portant sur des organismes vivants est nécessaire pour l'évaluation des risques liés à la diffusion de nouveaux produits dans l'environnement. Ces tests sont généralement lourds à mettre en oeuvre et doivent donc n'être utilisés qu'à bon escient, en programmant à chaque étape des expériences tenant compte de l'ensemble des données physicochimiques relatives aux produits étudiés et des résultats des essais effectués aux étapes précédentes. Les auteurs, à partir de leur propre expérience et d'une synthèse bibliographique, exposent les principes qui peuvent présider à une telle démarche et discutent des méthodes statistiques qui permettent de valoriser au mieux l'information recueillie.

  • Publication . Preprint . Conference object . Article . Other literature type . 2003
    Open Access English
    Authors: 
    Berestycki, Nathanael; Durrett, Rick;
    Publisher: HAL CCSD
    Country: France

    Our work is motivated by Bourque and Pevzner's (2002) simulation study of the effectiveness of the parsimony method in studying genome rearrangement, and leads to a surprising result about the random transposition walk on the group of permutations on $n$ elements. Consider this walk in continuous time starting at the identity and let $D_t$ be the minimum number of transpositions needed to go back to the identity from the location at time $t$. $D_t$ undergoes a phase transition: the distance $D_{cn/2} \sim u(c)n$, where $u$ is an explicit function satisfying $u(c)=c/2$ for $c \le 1$ and $u(c)1$. In other words, the distance to the identity is roughly linear during the subcritical phase, and after critical time $n/2$ it becomes sublinear. In addition, we describe the fluctuations of $D_{cn/2}$ about its mean in each of the threeregimes (subcritical, critical and supercritical). The techniques used involve viewing the cycles in the random permutation as a coagulation-fragmentation process and relating the behavior to the \Erd\H{o}s-Renyi random graph model. Comment: Revisions include considerable changes in the presentation of section 6 (proof of the CLT in the supercritical regime), and several typos corrected. Also, the figures are now available as a separate .ps file

  • English
    Authors: 
    Yu Lu; Claire Le Paven; Hung Viet Nguyen; Ratiba Benzerga; Laurent Le Gendre; Stéphane Rioual; Franck Tessier; François Cheviré; Ala Sharaiha; Christophe Delaveaud; +1 more
    Publisher: HAL CCSD
    Country: France

    International audience; Perovskite lanthanum titanium thin films were deposited on Nb-doped (001) SrTiO3 substrates by reactive RF magnetron sputtering using a La2Ti2O7 target. Oxynitride LaTiO2N films were obtained using N2 rich plasma; they display a variation of their dielectric constant as a function of DC bias in the low frequency range but not in microwaves. The dielectric constant (epsilon) values are high with, for example, epsilon = 325 at 100 kHz. The oxide films, obtained in O2 rich plasma, are composed of an unusual La2Ti2O7 phase with an orthorhombic cell. The films are (101) epitaxied on Nb:SrTiO3 substrates. The dielectric constant value of films is around 77 with losses 0.076 at 100 kHz; no agility of epsilon in low and high frequencies is detected. Composite and bilayer films, with oxynitride and oxide phases, exhibit a variation of epsilon under DC bias in low frequencies with, for example, an agility of 15% at 100 kHz with a maximum applied field of 40 kV/cm for the LaTiO2N (200 nm)/La2Ti2O7 (250 nm) bilayer.

  • Publication . Conference object . 2020
    English
    Authors: 
    Privat, Jean-Marie;
    Publisher: HAL CCSD
    Country: France

    International audience

  • English
    Authors: 
    Hee Ryung Lee; Christian Lotz; Florian Groeber-Becker; Sofia Dembski; Enric Garcia-Caurel; Razvigor Ossikovski; Tatiana Novikova;
    Publisher: HAL CCSD
    Country: France

    Mueller transmission microscopy has been used for both theoretical and experimental studies of anisotropic scattering biological tissue. In our prior study, the linear dependence of retardance and quadratic dependence of depolarization on thickness was demonstrated for a dermal layer of skin model. During the primary analysis of polarimetric images of histological cuts both epidermal and dermal layers were delineated manually in order to calculate the spatially averaged values of retardance and depolarization parameters. Consequently, these average values contained the contribution of outliers (noise, not correctly identified pixels, etc.) which produces large standard deviation and biased mean values of the parameters mentioned above. For preventing the errors, the normalized maps of optical properties were calculated pixel-wise taking into account local optical density (e. i. logarithm of M11 element of Mueller matrix at each image pixel) to compensate varying tissue thickness across the cut area. Furthermore, the DBSCAN (Density-based spatial clustering of applications with noise) algorithm was applied for segmentation of microscopic images using the normalized values of retardance, depolarization, and intensity. From the results of image segmentation, we could discriminate the regions of dermal and epidermal layers in Muller microscopic images of skin cuts more accurately and obtain more reliable values of tissue’s optical properties.

  • English
    Authors: 
    Freund, Frédérique; Muller, Catherine;
    Publisher: HAL CCSD

    International audience; Understanding teachers’ rationale and strategies for implementing CALL in their practices is of critical importance in teacher education research, especially with a view to designing teacher training programs that address real-life issues faced by practitioners and that help develop both a reflective and a pragmatic approach to the integration of technology in the language learning classroom (Egbert & Petrie, 2005; Stockwell, 2009; Guichon & Hauck, 2011).The present contribution proposes to explore an in-service teacher’s own perspective on her technology-mediated practice in the specific context of a blended EFL course, which combines face-to-face group instruction in a computer lab with individualized, self-paced instruction within an LMS.It aims at assessing what motives inform the teacher’s actions in such a context, with a focus on what she perceives her mediating role may be, both in managing the relationship between the different spaces that she and the learners inhabit (in class and online), and in developing learners’ autonomy (Borg & Al-Busaidi, 2012).The blended EFL course presented in this in-depth case study is an English course for Master’s students in history at a French university which focuses on the acquisition of English speaking skills. In addition to field observation, video stimulated recall was used to provide access to the teacher’s perceptions (Lazarton, & Ishihara, 2005). Data is interpreted using a qualitative, inductive approach.The analysis of the teacher’s discourse provides insight into what successful integration of CALL in a blended learning environment entails from the practitioner’s perspective and what role she should play in a learner-centred approach, especially in ensuring the human aspect of the pedagogical relationship is preserved.As a conclusion, we propose to briefly discuss the potential of using video-stimulated recall as a self-confrontation method, both for the professional development of pre- and in-service teachers and for fostering interaction between research and practice.

  • Publication . Conference object . Part of book or chapter of book . 2016
    English
    Authors: 
    Sanseverino-Godfrin, Valérie;
    Publisher: HAL CCSD
    Country: France

    International audience; Recently, regarding the explosion of AZF, she French Supreme administrative court, the State Council (Conseil d’Etat) estimated that the state department charged with the inspection of the industrial activities (DREAL – Direction Régional de l’Environnement, de l’Aménagement et du Logement) did not commit any negligence in the inspection of the plant and had no part of the responsibility in the accident. The judges based their decision on the fact that in the safety report, elaborated in 1990 by the industrial, the danger of the explosion of the ammonium nitrate warehouse was not considered. Moreover, nobody informed the state department of the lack of compliance of the industrial activity with the legal measures and so, of the lack of safety. However, the judicial inquiry lead following the accident had demonstrated serious negligence in the management of the site, which had never been the subject of a report by the DREAL, despite eleven inspection visits within the last six years before the explosion. The State Council has confirmed a certain conception of the inspection of the industrial plants: inspection appears as one of the modes of the regulation in the environmental and safety field, with an evolution of the role of the State and the industrial.

  • Authors: 
    W. Aouimeur; Sylvie Lepilliet; Christophe Gaquiere; Estelle Lauga-Larroze; Jean-Daniel Arnould; J. Moron-Guerra; Thomas Quemerais; Daniel Gloria; Ayssar Serhan;
    Publisher: IEEE
    Country: France

    International audience; This paper describes an in-situ reflectometer for one port VNA in 160 to 200 GHz band (G Band). The proposed system is fabricated in 55 nm SiGe BiCMOS technology from STMicroelectronics. Measured performances of system shown 110 mW of power DC consumption from a 1.2 V supply. A 180 GHz nMOS is measured as the device-under-test (DUT) after an in-situ calibration. The results obtained using this fully integrated VNA have been compared to a commercial VNA. A discrepancy of 0.3 dB is noted between the two systems on magnitude over a wide frequency range 172-192 GHz. Without calibration, the “raw” dynamics range of the system is limited by the directivity of the coupler which is 20 dB at 140-220 GHz. This dynamic will be improved after the calibration. The SiGe chip size is 3.3 mm2 . To our best knowledge, the presented in-situ VNA have the first results compared to the recently published and are the first with an in-situ calibration integrated in SiGe or CMOS technologies.

  • Publication . Part of book or chapter of book . 2015
    Open Access English
    Authors: 
    Milad Ashour Pour; Massimo Zanardini; Andrea Bacchetti; Simone Zanoni;
    Publisher: HAL CCSD
    Country: Italy

    Part 4: The Role of Additive Manufacturing in Value Chain Reconfigurations and Sustainability; International audience; With an ever growing diffusion of Additive Manufacturing (AM) system in industrial and commercial level, as well as the direct and indirect dynamics which are being introduced resulting from its inclusion as a possible production technology on companies’ portfolio, the need to reconfigure production system and adapt the production strategy becomes even more relevant than before. There are several studies which have emphasized on the importance of a paradigm shift in order to exploit advantages of AM, not only considering changes within design and functionality of the product, but also concerning AM’s impact on the entire value chain (re)configuration. Thus, it is of crucial importance to take into consideration that for this shift to be feasible and manageable, there is a need to include both technical and managerial aspects of manufacturing. This work proposes an economic insight in order to provide a guideline for the proper evaluation of AM system implementation.

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