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Le lien entre la qualité empêchée (QE) et la fidélité des employés : le cas des gestionnaires d’aires d’accueil des gens du voyage (Gdv)
No full textNational audienceThis article explores the impact of impeded quality on employee loyalty. To this end, a study was conducted within an association in the Centre-Val de Loire region, France, based on nineteen semi-structured interviews with managers-regulators of reception areas for travelers—“gens du voyages” (GDV). The results indicate a manifestation of organizational loyalty despite the presence of constraints that generate perceptions of impeded quality (IQ). The findings of this study indicate that this loyalty can be attributed to two primary factors. First, the perceived constraints are not directly attributable to the organization, thereby limiting their negative impact on employee loyalty. Second, the appreciation of their autonomy at work, the perceived organizational support, and their adherence to the association’s values foster a sense of reciprocity, thereby strengthening the bond between employees and their organization. The findings underscore the pivotal function of social interactions in the development of organizational loyalty, particularly in scenarios where quality is constrained.Cet article examine les effets de la qualité empêchée sur la fidélité des employés. À cette fin, une étude a été menée auprès d’une association de la région Centre-Val de Loire, s’appuyant sur 19 entretiens semi-directifs réalisés auprès des gestionnaires-régisseurs des aires d’accueil des gens du voyage (Gdv). Les résultats mettent en évidence une manifestation de la fidélité organisationnelle, malgré la présence de contraintes générant des perceptions de qualité empêchée (QE). Cette fidélité s’explique par deux principaux facteurs : d’une part, le fait que les contraintes perçues ne sont pas directement imputables à l’organisation, ce qui limite leur effet négatif sur la fidélité des employés ; d’autre part, la valorisation de leur autonomie au travail, le soutien organisationnel perçu et l’adhésion aux valeurs de l’association, qui favorisent un sentiment de réciprocité et renforcent le lien entre les employés et leur organisation. Ces résultats soulignent ainsi le rôle central des échanges sociaux dans la construction de la fidélité organisationnelle, même en contexte de qualité empêchée
From erbium(iii) to samarium(iii): generalized photomodulation of NIR to red lanthanide luminescence with a DTE ligand and its versatile role in the quenching processes
No full textCCDC 2402724 contains the supplementary crystallographic data for this paper.51 - All experimental procedures, analytical data and spectra are available in the supplementary information (SI). Supplementary information is available. See DOI: https://doi.org/10.1039/d5sc07174g.International audienceIn this article, we report that a stable molecular system combining three DTE-β-diketonate units, a phenanthroline ligand and a lanthanide ion provides, for an unprecedented panel of lanthanide(III) ions, efficient luminescence together with an emission quenching process under UV light with very high efficiency. Indeed, this process is applicable to visible emitters (samarium(III) and europium(III)), and more importantly to different NIR emitters (ytterbium(III), neodymium(III) and erbium(III)), and it can be reversed under visible light irradiation in a highly repeatable way. The luminescence sensitizing and quenching mechanisms were further investigated with experimental and theoretical tools to decipher the peculiar and complex role of the DTE-β-diketonate units. In particular, these studies reveal the existence (i) of a very high cyclization quantum yield of the open isomer in the presence of oxygen with a triplet mediated mechanism depending on the lanthanide ion nature, and (ii) of a dark triplet state located on the closed isomer explaining the quenching of the NIR and visible emitters
De quelle étoffe les héros sont-ils faits ? Autour d’une querelle sur les modèles cinématographiques offerts à la jeunesse française (1945-1968)
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A Broadband, Wide-Angle, and Dual-Polarized 1-Bit Reconfigurable Reflect-Array at Ka-Band With Independent Control of Polarizations
No full textInternational audienceA broadband 1-bit reconfigurable reflect-array antenna (RRA) featuring independent dual-polarized beam-scanning capability is reported at Ka-Band. By jointly exploiting two modes containing an electric resonance and a magnetic resonance, a novel dual-polarized reconfigurable reflective cell with 1-bit phase resolution and simple laminates is proposed. Within each RRA cell, only two orthogonally-aligned PIN diodes are utilized to provide independent dynamic phase control respectively for the two orthogonal linear polarizations. For experimental verification, a 20 × 20-cell dual-polarized RRA is fabricated and measured. The RRA prototype is controlled by a field programmable gate array (FPGA)-based logic module, where each cell is connected with two separate bias lines. Three sets of phase masks are employed, each with an optimized reference phase, for achieving a flattened gain response over a wide frequency range. The RRA prototype exhibits a 1-dB gain bandwidth wider than 27%, a peak gain of higher than 23 dBi, and a peak aperture efficiency of about 22% for both polarizations. Moreover, within the entire operating frequency band, the beams of both polarizations support a wide-angle scanning coverage within the range of −60° to +60°. The proposed dual-polarized RRA could be a promising candidate for millimeter-wave wireless communication and sensing/imaging systems
Déploiement de réseaux denses de suivi de la pression lumineuse pour des actions territoriales: les cas de l'île de La Réunion et de la Brière, France
No full textInternational audienceDense networks of photometric sensors offer high-frequency, high-resolution data at unprecedented spatial scales. Such arrays detect lighting variations across minutes to years, enabling both short- and long-term assessments, while also enhancing skyglow and radiative transfer modeling. Critically, they support fine-scale evaluation of lighting policies — such as LED transitions or dimming regulations — by tracking their effects on sky brightness. These systems also enable near-continuous monitoring of Artificial Light At Night (ALAN) changes with atmospheric conditions including aerosols and cloud cover, and help validate satellite-derived products while informing ecological and health impact assessments. In this contribution, we present high-resolution datasets from two dense TESS-W sensor networks deployed for long-term ALAN monitoring in: (1) Réunion Island, a French territory in the Indian Ocean with volcanic terrain, high biodiversity, and a rapidly urbanizing coast; and (2) the Brière region, a wetland near France’s Atlantic coast, home to a regional nature park and sensitive nocturnal ecosystems. These networks provide continuous, multi-year measurements of night-sky brightness at fine spatial (~km) and temporal (~minute) scales. We describe the network architecture, calibration procedures, data processing pipeline, and access details. By making these high-resolution ALAN datasets openly available, this work enhances our ability to monitor light pollution and evaluate the effectiveness of mitigation strategies. Designed as part of the Observatoire de l’Environnement Nocturne of the French National Centre for Scientific Research (CNRS), these datasets offer a robust empirical foundation for investigating the multifaceted dynamics of light pollution across ecological, atmospheric, sociocultural, and territorial contexts. They also contribute to publicengagement and educational initiatives, fostering broader awareness and collective action toward preserving the nocturnal environment
Elliptic butterflies
No full textWe study natural evaluation and interpolation problems for elliptic functions and prove that they allow a recursive treatment using a variant of classical butterflies first introduced by Gauss. We deduce the existence of straight-line programs with complexity in d log(d) for these problems and present applications to finite field arithmetic, coding theory and cryptography
Advances in Semiconductor Physics, Devices and Quantum Dots - Nanotechnology and Future Challenges
No full textInternational audienceThis book, Advances in Semiconductor Physics, Devices and Quantum Dots - Nanotechnology and Future Challenges, is a compilation of chapters on research in the fields of semiconductor physics, devices, and quantum dots. The chapters have been reviewed, and they offer a complete overview of what has been developed recently. The book comprises chapters written by various researchers and reviewed by experts in nanotechnology and engineering. Each chapter is complete in itself, but they are all connected by a common research study topic. This publication aims to provide a thorough overview of the latest research efforts by international authors in the field. It also aims to open new possible research paths for further novel developments
L’histoire environnementale, une histoire culturelle ?
No full textInternational audienceLe texte qui suit est issu de la table ronde, organisée par Anne-Claude Ambroise-Rendu et Anna Trespeuch-Berthelot, qui s’est tenue au congrès de l’Association pour le développement de l’histoire culturelle (ADHC) le 28 septembre 2024 au Musée de la Chasse et de la Nature, à Paris. Celle-ci a réuni Guillaume Blanc, Steve Hagimont, Charles-François Mathis et Émilie-Anne Pépy.PlanPrésentation d’Anne-Claude Ambroise-Rendu et Anna Trespeuch-Berthelot -- Le renouvellement du questionnaire historien -- Une commune déconstruction des objets -- Des objets et des méthodes -- Du rapport au temps comme une invitation à l’engagement Table ronde</b
Pest localization through sequential data assimilation with pheromone sensors
No full textEarly detection and precise localization of insect pests are critical for the development of effective crop management strategies. This study introduces a Sequential Data Assimilation (SDA) method that integrates a pheromone propagation model with data pheromone sensors to infer spatio-temporal pheromone emission maps and deduce insect localization.The SDA method iteratively refines sensor positioning by leveraging predicted pheromone plumes, enabling sensors to adaptively reposition toward areas of higher pheromone concentration. This approach combines data assimilation, large-scale physics modeling, and statistical optimization to improve localization accuracy over time.The method is evaluated through numerical experiments, including toy cases with unsteady wind conditions and multiple pheromone sources, as well as a realistic case based on real agricultural landscapes and meteorological data. Results demonstrate that the method significantly enhances the accuracy of pest localization compared to traditional data assimilation approaches. The sequential repositioning of sensors reduces errors in pheromone emission inference and minimizes false absence predictions, even in challenging scenarios such as unsteady wind or multiple emission sources. This study highlights the potential of SDA for robust pest localization, offering a promising tool for precision agriculture and sustainable pest management
