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Towards an embedded architecture based back-end processing for AGV SLAM applications
No full textInternational audiencePlace recognition plays a crucial role in the Simultaneous Localization and Mapping (SLAM) process of self-driving cars. Over time, motion estimation is prone to accumulating errors, leading to drift. The ability to accurately recognize previously visited areas through the place recognition system allows for the correction of these drift errors in real-time. Recognizing places based on the structural aspects of the environment tends to be more resilient against variations in lighting, which can cause incorrect identifications when using feature-based descriptors. Nevertheless, research has predominantly focused on using depth sensors for this purpose. Inspired by a LiDAR-based approach, we introduce an inter-modal geometric descriptor that leverages the structural information obtained through a stereo camera.Using this descriptor, we can achieve real-time place recognition by focusing on the structural appearance of the scene derived from a 3D vision system. Our experiments on the KITTI dataset and our self-collected dataset show that the proposed approach is comparable to state-of-the-art methods, all while being low-cost. We studied the algorithm’s complexity to propose an optimized parallelization on GPU and FPGA architectures. Performance evaluation on different hardware (Jetson AGX Xavier and Arria 10 SoC) shows that the real-time requirements of an embedded system are met. Compared to a CPU implementation, processing times showed a speed-up between 4x and 10x, depending on the architecture
L'apport des évaluations informelles dans la méthodologie de conception collaborative d'un dispositif de rééducation impliquant ergothérapie et informatique
No full textInternational audienceThis paper presents the methodology followed in the TeMaCo project, which aims to develop a digital tool designed to make rehabilitation sessions more engaging and enjoyable. The system must be accepted both by the occupational therapist leading the session and by the patient undergoing rehabilitation. To achieve promising results in terms of acceptability, the design process involved 184 participants in feedback collection and evaluations, and over 1,000 people in activity trials conducted during four scientific or public events. This paper highlights how informal evaluations add value to the co-design process of a rehabilitation tool. By informal evaluation, we refer to an assessment with a fixed protocol which, unlike controlled evaluations that we qualify as formal, takes place during public events where visitors are invited to participate. Each informal evaluation contributed to refining the system to better meet user needs and to building a scientific evaluation whose results are promising. Looking ahead, future work will be carried out with occupational therapists to prepare a rehabilitation protocol integrating the system.Cet article présente la méthodologie suivie dans le projet TeMaCo dont l'objectif est de proposer un dispositif numérique permettant de rendre les séances de rééducation plus ludiques. Ce dispositif doit être accepté par l'ergothérapeute qui gère la séance et par la personne en rééducation. Pour obtenir un résultat prometteur en termes d'acceptabilité, le processus de conception a impliqué 184 personnes dans des recueils d'avis et des évaluations et plus de 1000 personnes pour essayer des activités, lors de 4 événements scientifiques ou grands publics. Cet article montre comment les évaluations informelles représentent une plus-value dans le processus de co-conception d’un dispositif pour la rééducation. Nous entendons par évaluation informelle, une évaluation avec un protocole fixe, qui, à la différence des évaluations en situation contrôlée quenous qualifions de formelles, se déroule lors d’événements publics, où les visiteurs sont invités à participer. Chacune des évaluations informelles a permis de concevoir un dispositif répondant au mieux au besoin et de construire une évaluation scientifique dont les résultats sont prometteurs. En perspective, un travail sera mené avec les ergothérapeutes pour préparer un protocole de rééducation utilisant le dispositif
Predicting the proportion of centennially stable soil organic carbon using mid-infrared spectroscopy
No full textInternational audienceRecent work has shown that it is possible to quantify the proportion of centennially stable soil organic carbon (SOC) by using Rock-Eval® thermal analysis results as input variables for PARTYsoc, a learning model calibrated on long term experiments data. This method of quantifying SOC biogeochemical stability holds promise for improving projections of SOC stock evolutions. Here, we assessed the potential of mid-infrared spectroscopy (MIR) as a lower-cost, higher-throughput technique to facilitate its wide-scale deployment. We compiled a spectral library of over 1,800 records obtained through the scanning of samples from the French Réseau de Mesure de la Qualité des Sols to calibrate a model using MIR data to predict the proportion of centennially stable SOC. The model gave accurate predictions (RMSE = 0.06, RPD = 2.21, RPIQ = 3.26), suggesting that MIR spectra contain relevant information on SOC biogeochemical stability. We then tried to transfer this model directly to datasets acquired using another MIR spectrometer on German and Finnish soil samples. The accuracy of the predictions was degraded, even when using the CORAL data alignment method to harmonise the different spectral datasets. Our results show that it is possible to predict the proportion of centennially stable carbon determined by the PARTYsoc model using MIR spectroscopy. However, we found that the transfer of such models to different soils, scanned with different instruments or different protocols, is difficult. Large-scale deployment of such models will require careful calibration transfer, probably associated to local calibration within a similar spectral space
Developing and evaluating a pedagogical tool for teaching energy: from storyboard to finalized digital comic
No full textInternational audienceThis study examines the pedagogical potential of a digital comic developed as part of the ERASMUS+ ECoSCOMICS program, which aimed to create engaging science education resources for secondary classrooms. The episode under focus, centered on the physical concept of energy, was first implemented in storyboard form and tested on three French ninth-grade classes to assess its effectiveness and develop its final version. This research relies on a priori analyses to hypothesize potential learning difficulties and levers. Students engaged with the comic both individually and collaboratively, answering pre- and post-session questionnaires as well as completing group tasks. Quantitative and qualitative analyses highlighted persistent difficulties in distinguishing between forms, sources, and transfers of energy, yet demonstrated progress in recognizing the principle of energy conservation. The visual and narrative elements of the comic were praised for making abstract concepts more accessible, although feedback also pointed to the density of content as a challenge. Based on these findings, the storyboard was revised to produce the finalized version of the comic, incorporating changes to address misconceptions, simplify visuals, and improve pacing
L’État postcolonial et les politiques du personnel policières « Outre-mer »: L’État postcolonial et les politiques du personnel policières « Outre-mer »
No full textInternational audienceIn Guadeloupe, common perception holds that police officers are Guadeloupeans while gendarmes are "metropolitans" (from mainland France). The majority of police officers on public streets are Guadeloupeans who return after long years in mainland France, whereas specialized service agents and management are predominantly from the mainland. In the gendarmerie, by contrast, the vast majority of gendarmes are "metropolitans," but approximately 15%—a limited and remarkably stable proportion over time—are Guadeloupean. The unequal representation of Guadeloupean agents across institutions, professions, and ranks is politicized in the archipelago, and several reforms (national and local) were intended to facilitate the return of those whom these institutions refer to alternately, sometimes ambiguously and not entirely interchangeably, as "natives" and/or "CIMM" (citizens from overseas territories). Despite these political initiatives, the proportion and distribution of Guadeloupean and mainland agents remain stable. This paper seeks precisely to explain how, despite reforms and the institutionalization of compensatory rights, the stable administration of police officers and gendarmes in Guadeloupe is maintained.Through an eleven-month ethnography within the territorial directorate of the national police and the overseas command of the Guadeloupe gendarmerie, I was able to study the processes reproducing this distribution of police positions. Based on observational and interview research, I demonstrate that despite national and local reforms and significant organizational differences, both the police and gendarmerie implement the same "personnel policy" that seeks to contain the territorialization of police forces.Indeed, the police and gendarmerie are composite organizations of professions and ranks, caught in significant spatial inequalities that structure a highly segmented professional space. Territorialization reforms have not been imposed uniformly, and so-called overseas territories, like management and specialized professions, still escape compensatory rights in the name of police rationale. In public security (the most visible police service, as its agents work at police station counters and on public streets, unlike criminal investigation and territorial intelligence), officers have indeed benefited from the reform: all those who transfer to Guadeloupe today now do so through CIMM status (the administrative category that recognizes belonging to a so-called overseas territory). But in other police services, among ranked officers, and among their military counterparts in the Gendarmerie, consideration of CIMM is highly varied, even completely absent. Beyond this unequal application of the rule, administrators and, in the field, police supervisors (from both the police and national gendarmerie) have significant discretionary margins to decide on police administration, through which they can circumvent these institutional guidelines, especially in these protected services (and ranks). Yet these administrators and supervisors, police officers and gendarmes alike, despite the stated institutional evolution regarding the territorialization of police forces in so-called overseas territories, share and implement the same policy: ensuring a "good balance between mainlanders and natives." In CIMM allocation, profiled recruitments, and exceptional transfers, compensatory rights are sometimes set aside, circumvented, or diverted to achieve this objective.En Guadeloupe, le sens commun consiste à dire que les policiers sont des guadeloupéens et les gendarmes des "métropolitains". Effectivement, la majorité des policiers sur la voie publique sont des guadeloupéens qui rentrent après de longues années en hexagone, alors que les agents des services spécialisés et la hiérarchie sont plutôt des hexagonaux. En gendarmerie au contraire, la vaste majorité des gendarmes sont des "métropolitains", mais environ 15%, une proportion limitée et remarquablement stable dans le temps, sont guadeloupéens. L'inégale représentation des agents guadeloupéens entre les institutions, métiers et grades est politisée sur l'archipel, et plusieurs réformes (nationales et locales) devaient permettre le retour facilité de ceux que ces institutions appellent tour à tour, de manière parfois ambiguë et pas complètement interchangeable, des "originaires" et/ou des "CIMM". Malgré ces séquences politiques, la proportion et la distribution des agents guadeloupéens et hexagonaux restent stables. Cette communication cherche à expliquer comment, malgré les réformes et l'institutionnalisation de droits compensatoires, s'organise la reproduction des mêmes logiques d'administration des policiers et des gendarmes en Guadeloupe. Je m'appuie sur une ethnographie de onze mois au sein de la direction territoriale de la police nationale et le commandement d'outre-mer de la gendarmerie de Guadeloupe. À partir d'une enquête par observation et par entretien, je montre que malgré des réformes nationales et locales, et d'importantes différences organisationnelles, la police et la gendarmerie mettent en oeuvre une même "politique du personnel" qui cherchent à circonscrire la territorialisation des forces de police. En effet, la police et la gendarmerie sont des organisations composites de métiers, de grades, prises dans d'importantes inégalités spatiales qui structurent un espace professionnel très segmenté. Les réformes de territorialisation ne s'y sont pas imposées de manière équivalente, et les territoires dits d'Outre-mer, comme la hiérarchie et les métiers spécialisés, échappent encore aux droits compensatoires au nom de la raison policière. En sécurité publique (le service de police le plus visible, puisque ses agents travaillent au guichet des commissariats et sur la voie publique, contrairement à la police judiciaire et aux renseignements territoriaux), les policiers ont effectivement bénéficié de la réforme : tous ceux qui mutent en Guadeloupe aujourd'hui le font désormais grâce aux CIMM (la catégorie administrative qui reconnaît l'appartenance à un territoire dit d'Outre-mer). Mais dans les autres services de police moins visibles, chez les gradés, et chez les homologues gendarmes soumis à un droit du travail militaire, la prise en compte des CIMM est très contrastée, voire complètement absente. En plus de cette inégale application de la règle, les gestionnaires et, sur le terrain, les cadres policiers (de la police et de la gendarmerie nationale) disposent de quelques marges discrétionnaires pour décider de l'administration des policiers, et grâce auquelles ils peuvent contourner ces orientations institutionnelles, à forceriori dans ces services (et grades) protégés. Or, ces gestionnaires et ces cadres, policiers et gendarmes, et ce malgré l'évolution institutionnelle affichée quant à la territorialisation des forces de police dans les territoires dits d'Outre-mer, partagent et mettent en œuvre une même politique : assurer un "bon équilibre entre hexagonaux et originaires". Dans l'attribution des CIMM, les recrutements profilés, les mutations dérogatoires, les droits compensatoires sont parfois écartés, contournés ou détournés pour atteindre cet objectif
Les ateliers d’écriture et d’échange sur l’activité : un dispositif de recherche collaborative analyseur des besoins de prudence des professionnels de la protection de l’enfance
No full textInternational audienceLes ateliers d'écriture et d'échange sur l'activité : un dispositif de recherche collaborative analyseur des besoins de prudence des professionnels de la protection de l'enfance</div
Reflexive Methods in Qualitative Fieldwork: The Role of Local Mediators in Multicultural Contexts
No full textInternational audienceThis presentation delves into fieldwork experience acquired in different sociocul-tural settings during the first semester of 2025, particularly in France (Lyon) and Hungary (Budapest), within the context of a comparative analysis of immigrant communities and their positionality in challenging media environments. Each case study offered insights on intergroup dynamics and migrant-led critical media dis-course, despite the obstacles encountered during the organization and execution of the fieldwork research plan. More specifically, the attendance and demographic rep-resentation were limited in Lyon, while Budapest was marked by open and inclusive dialogues among multiple participants. Because of the different nature of fieldwork conditions, it is significant to underline the unpredictable realities of research on mo-bility and integration.The original research design included focus groups to listen to shared experiences on media representations on migration and analyze their reactions to negative media portrayals from a qualitative research standpoint. Therefore, the fieldwork researcher emphasizes the need to perform flexible and creative methods to address these chal-lenges: the involvement of local mediators for recruitment purposes, the inclusion of visual prompts, and the introduction of small-group discussion groups. Once the new research design was adopted, it had a positive impact in Budapest, where collabora-tion with NGOs and community spaces helped build trust and intercultural dialogues. However, in Lyon, similar efforts did not yield the expected results, possibly due to limited engagement by local mediators during the recruitment process and fieldwork research plan execution time and conditions.Based on the acquired fieldwork experience, it can be argued that external fac-tors play a significant role in its implementation and results, especially when this in-volves the mobilization of individuals with diverse and multicultural backgrounds. Hospitality centers and associations can act as ‘bridges’ between research and on-the-ground realities, which can help the researcher understand their positionality and monitor potential tensions between institutional expectations and field-based practice. Methodological reflexivity eventually positions itself among the vital elements to manage processes and results during the fieldwork research organization and execu-tion. Lastly, it is worth noting that creative methods can be both alternatives and val-uable tools for ethical knowledge production and dissemination