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Tsuji–Trost Based Cascades: From Passerini Adducts of Cinnamaldehyde to Allylated Oxazolones
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Les relations entre sciences, technologies et territoires au cœur de la souveraineté nationale : une approche structurale sur longue période
No full textThis thesis delves into the territorial dimension of scientific and technological knowledge exchange, a pivotal aspect of the innovation process. It focuses on defence-related technological fields, such as weaponry, aerospace equipment and 3D printing, to scrutinize how scientific advancements are integrated into technological development. Furthermore, our analysis focuses on measuring strategic autonomy of national territories, assessing their capacity to independently produce, use and disseminate knowledge. This form of autonomy in critical defence innovation sectors is a key factor in current discussions on national sovereignty.From an institutionalist viewpoint, this manuscript situates the innovation process within the national innovation system framework. In this context, territory is understood as a social, political and cultural construct that facilitates interactions and the exchange of knowledge.Our empirical method mobilizes quantitative methods using a large number of patent data and scientific publications to establish global knowledge networks, based on citations and semantic proximity. In this regard, we employ a structural approach, integrating influence graph theory consolidated with econometric models.Our findings reveal two distinct global knowledge networks. The first, encompassing explicit knowledge, can be easily disseminated, and assimilated across various territories. The analysis of these networks permits a comparative evaluation of the control over strategic knowledge among different territories, highlighting situations of dominance or dependence on external sources of knowledge. The second network, with more local roots, comprises tacit, applied knowledge that is intrinsic to individuals and their social interaction networks, thereby being geographically bounded. This network accounts for the sustained presence of national expertise over an extended period, notwithstanding the globalized nature of knowledge exchange driven by globalisation and the advancement of information and communication technologies.Our study shows that the coexistence of these networks is essential in knowledge maturation. Despite the more codified and globalized nature of scientific activity compared to technological, it retains strong territorial ties, fostering local innovation through tacit knowledge exchange. These insights suggest that investments in specific domains are crucial for enhancing national sovereignty in strategic innovation.Cette thèse explore la dimension territoriale des échanges de connaissances scientifiques et technologiques essentiels au processus d'innovation sur des domaines technologiques intéressant la défense, tels que l'armement, l'équipement aérospatial et l'impression 3D. Elle explore l'intégration des avancées scientifiques dans le développement technologique et analyse l'autonomie stratégique des territoires en tant que capacité à produire, utiliser et diffuser des connaissances de manière indépendante. Cette autonomie dans les secteurs stratégiques de l'innovation de défense est au coeur des enjeux contemporains de souveraineté nationale. Adoptant une perspective institutionnaliste, cette recherche positionne le processus d'innovation au sein d'un système d'innovation national, envisageant le territoire comme une entité sociale, politique et culturelle qui facilite l'échange de connaissances. Notre démarche empirique repose sur l'utilisation de données de brevets d'invention et d'articles scientifiques à grande échelle pour créer des réseaux de connaissances mondiaux, fondés sur les citations et la proximité sémantique. Nous adoptons pour cela une approche structurale qui mobilise la théorie des graphes d'influence, combinée à des méthodes économétriques robustes pour interpréter nos mesures.Nous observons l'existence de deux réseaux de connaissances à l'échelle mondiale. Le premier, composé de connaissances explicites, facilement diffusables et assimilables par les différents territoires. L'analyse de ces réseaux permet de comparer la maîtrise des connaissances stratégiques entre territoires, identifiant des situations de domination ou de dépendance vis-à-vis des productions extérieures. Le second réseau, plus ancré localement, inclut des connaissances tacites, incarnées dans les individus et leurs réseaux d'interactions sociales et donc géographiquement bornées. Ce réseau permet d'expliquer la persistance des expertises nationales à long terme, malgré l'internationalisation des échanges de connaissances facilitée par la mondialisation et le développement des technologies de l'information et de la communication.Nous démontrons que la coexistence de ces réseaux est cruciale dans le processus de maturation des connaissances. Bien que l'activité scientifique soit plus codifiée et globalisée que l'activité technologique, elle présente un fort ancrage territorial, stimulant l'innovation locale par des échanges de connaissances tacites. Ces résultats soutiennent le financement de certains domaines scientifiques comme vecteur pour renforcer la souveraineté nationale sur les innovations stratégiques
A model-based deep learning framework for damage classification and detection in polycarbonate infused with AEROSIL under dynamic loading conditions
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High-Resolution Seismic Imaging for Dam-Rock Interface using Full-Waveform Inversion
No full textInternational audienceWe are interested in imaging the interface between the concrete structure of the hydroelectric dam and the underlying rock using non-destructive seismic waves. Our method, combining "Full Waveform Inversion" with shape optimization, produces high-resolution images. Numerical results from realistic synthetic data demonstrate the method ability to accurately recover the interface with a limited number of measurements
Quantification of microscale factors for fatigue failure in NiTi shape memory alloys
No full textInternational audienceFatigue behavior is intrinsically linked to microstructural alterations induced by cyclic loading. However, the quantification of microstructural defects associated with fatigue damage of NiTi shape memory alloys (SMAs) is lacking, which hinders the development of a physically based fatigue criterion. To this end, a multi-scale experimental analysis was conducted on cyclically deformed NiTi SMAs, which evidenced a strong correlation between microstructural inhomogeneity and localized deformation behavior. The microstructural change associated with fatigue was quantified in terms of stored strain–energy, with the highest values observed in the regions where fatigue cracks initiate. Consequently, stored energy is deemed as an effective fatigue indicator, offering valuable insights for future work in the design and optimization of SMAs’ structures against fatigue
ACCURATE PROCESSING OF MULTIBEAM ECHOSOUNDER BACKSCATTER BASED ON STATISTICAL ANALYSIS OF SNIPPETS DATA
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Palladium-Catalyzed C8-H Functionalization of Naphthalenes: New Methodologies and Synthetic Applications
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Robustness Assessment of AI-Based 2D Object Detection Systems: A Method and Lessons Learned from Two Industrial Cases
No full textInternational audienceThe reliability of AI-based object detection models has gained interest with their increasing use in safety-critical systems and the development of new regulations on artificial intelligence. To meet the need for robustness evaluation, several authors have proposed methods for testing these models. However, applying these methods in industrial settings can be difficult, and several challenges have been identified in practice in the design and execution of tests. There is, therefore, a need for clear guidelines for practitioners. In this paper, we propose a method and guidelines for assessing the robustness of AI-based 2D object detection systems, based on the Goal Question Metric approach. The method defines the overall robustness testing process and a set of recommended metrics to be used at each stage of the process. We developed and evaluated the method through action research cycles, based on two industrial cases and feedback from practitioners. Thus, the resulting method addresses issues encountered in practice. A qualitative evaluation of the method by practitioners was also conducted to provide insights that can guide future research on the subject
Performance Analysis of Power Allocation and User-Pairing Techniques for MIMO-NOMA in VLC Systems
No full textInternational audienceIn this paper, we evaluate the performance of multiple-input multiple-output (MIMO) communication systems applied with a non-orthogonal multiple access (NOMA)-based indoor visible light communication (VLC). We present two efficient user-pairing algorithms for NOMA in VLC, aiming to enhance achievable data rates effectively. Our investigation involves the application of three low-complexity power allocation techniques. Comparative analysis reveals performance enhancements when employing the proposed schemes, especially when contrasted with NOMA without user pairing and orthogonal frequency division multiple access (OFDMA). Additionally, we explore the performance of both algorithms in scenarios with both even and odd numbers of users. Simulation results demonstrate the superiority of NOMA in comparison to OFDMA