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Implementation and Performance Analysis of a Digital BPSK Demodulation Technique for Galvanic-Coupling Communication
No full textInternational audienceThis paper presents a digital demodulation technique for use in galvanic coupling intra-body communication (GC IBC) with BPSK-modulated signals at low frequencies (below MHz). The technique relies on a direct oversampled acquisition of the BPSK-modulated signal with an analogueto-digital converter (ADC) associated with an original digital processing algorithm to extract the demodulated data from the acquired samples. The originality of the solution resides in the digital processing algorithm which combines several mechanisms to fully exploit the redundancy present in the collected samples in order to provide a high degree of robustness, while maintaining a low level of complexity compatible with efficient implementation in a microcontroller. Simulation and measurement results are presented, confirming the robustness of the proposed solution. In particular, hardware measurements carried out under controlled conditions demonstrate very good performance, with a Bit Error Rate (BER) below 3 × 10 -5 for a signal with a Signal-to-Noise Ratio (SNR) of -5 dB. The proposed solution is also validated under real conditions with a GC communication realized through the back muscle of a fish, resulting in a BER < 2.5 × 10 -6
The BIOMASP+ project on biosphere-atmosphere exchanges and their role in air pollution in the subtropical megacity of São Paulo: motivations, methods and preliminary observations
No full textInternational audienceAir pollution, especially in urban areas, is the result of a complex mixture of natural and anthropogenic emissions and their atmospheric processing. It causes millions of premature deaths worldwide and affects plant metabolism, which in turn alters the emissions of Biogenic Volatile Organic Compound (BVOCs) by plants. By taking the subtropical Metropolitan Area of São Paulo (MASP) as a natural laboratory, the BIOMASP+ project (BIOsphere-atmosphere interactions in the Metropolitan Area of São Paulo - plus) a ims to evaluate the interplay between the biosphere and secondary pollution (ozone and SOA formation and aging). The Brazilian Atlantic Forest (Mata Atlântica) is the target ecosystem as the fifth biodiversity hotspot in the world. Here we present the scientific motivations of the project, its methodology and the preliminary observations from the Special Observation Periods of year 2023 (SOP1, 2, 3 and 4). BIOMASP+ is (i) integrative, by combining in-situ/remote/laboratory observations andmodeling, (ii) multidisciplinary, addressing micrometeorology, urban climate, atmospheric chemistry and biology. The project involves multiple nested scales: from leaf to above-canopy levels, from very short time (microseconds) to multi-year scale, from few millimeters (turbulence scale) to synoptic scale. In particular, the experimental effort relies on the implementation of two contrasting supersites (primary forest and urban forest) with a 30-m and 20-m flux towers, respectively, and a variety of state-of-the-art instruments. Ambient observations and the quantification of BVOC emissions have highlighted the complex interactions between meteorology, atmospheric composition of pollution, biogenic emissions of representative remnants of the Atlantic Forest and anthropogenic emissions
De la parole en classe à l’oralité en recherche: Dynamiques interactionnelles et épistémologie de terrain
No full textThis Habilitation à Diriger des Recherches manuscript examines classroom pedagogical interactions as a privileged site for the co-construction of meaning and the acquisition of orality. It is based on multimodal corpora recorded in authentic contexts, combining speech, gestures, prosody, and emotional regulation, in order to analyze how teachers and learners adjust their discourse and postures. The first part explores interactional mechanisms and the role of reformulations, explanations, and multimodality in learning. The second part investigates the construction and exploitation of complex corpora (emotions, learner writing, literature, adjustments), highlighting both the diversity of objects and the coherence of an empirico-interpretative approach. The third part focuses on the teaching of pronunciation, from the methodological heritage of phonetic correction to the combined contributions of the verbo-tonal method and the neurolinguistic approach, in order to propose an embodied and contextualized pedagogy of pronunciation. The final chapter adopts an epistemological and transdisciplinary perspective, shedding light on the researcher’s stance in the face of digital humanities, automation, and the ethical issues related to multimodal corpora. Taken together, the manuscript reflects a research trajectory rooted in the field, open to disciplinary tensions and hybridizations, and oriented toward sharing within a reflexive and formative perspective.Ce manuscrit d’Habilitation à Diriger des Recherches interroge les interactions pédagogiques en classe de langue comme lieu privilégié de co-construction du sens et d’acquisition de l’oralité. Il s’appuie sur des corpus multimodaux filmés en contextes authentiques, articulant parole, gestes, prosodie et régulations émotionnelles, pour analyser comment enseignants et apprenants ajustent leurs discours et leurs postures. La première partie explore les mécanismes interactionnels et la place des reformulations, des explications et de la multimodalité dans l’apprentissage. La deuxième examine la constitution et l’exploitation de corpus complexes (émotions, écrits d’apprenants, littérature, ajustements), montrant la diversité des objets et l’unité d’une démarche empirico-interprétative. La troisième se concentre sur l’enseignement de la prononciation, depuis les héritages méthodologiques de la correction phonétique jusqu’aux apports conjoints de la méthode verbo-tonale et de l’approche neurolinguistique, afin de proposer un enseignement de la prononciation incarné et contextualisé. Le dernier chapitre adopte une perspective épistémologique et transdisciplinaire. Il met en lumière la posture de chercheuse face aux défis des humanités numériques, de l’automatisation et des enjeux éthiques liés aux corpus multimodaux. L’ensemble témoigne d’un parcours scientifique ancré dans le terrain, ouvert aux tensions et aux hybridations disciplinaires, et orienté vers le partage dans une perspective réflexive et formatrice
Three non-capitalist approaches of peasant economics mobilising the principle of reciprocity
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/616172/)International audienceSeveral socio-economic and socio-anthropological approaches associate peasant agricultures to production and redistribution systems based on other conceptions of value than this of capitalistic market exchange and on other relations than competition for the accumulation of private profit. This article examines three proposals from diverse backgrounds but sharing a common analysis of peasant farming around the notions of ethics, affection, autonomy and resistance. There are the moral economy of Scott (1976), the economy of affection of Hyden (1980) and the peasant principle of Ploeg (2008). These three authors also refer to the principle of reciprocity; thus, I propose first to analyze their contribution regarding the theory of reciprocity in anthropology (Scubla, 1985; Temple, 1997 and 2003, Sabourin, 2012) and, secondly, I will examine how these approaches could dialogue. The article is divided in three parts. The first proposes a reading of the three contributions; the second presents briefly the main points of the theory of reciprocity and the third one discusses commons lessons and perspectives of these approaches
Access to agricultural lands influences the effects of seasonal drought on early growth and juvenile body mass in a large herbivore
No full textInternational audienceIncreasing rainfall deficits threaten the persistence of terrestrial large herbivores, yet, very few studies have investigated the effects of droughts on populations inhabiting anthropized areas, which dominate European landscapes. We investigated how rainfall deficits (measured using the Standardized Precipitation Index, SPI) and local agricultural land use shaped the early growth of fawns and the body mass that they attained by their first winter in a population of European roe deer (Capreolus capreolus) in southwestern France. Using data on 155 new-born fawns, we found that early growth decreased as local woodland availability increased, irrespective of spring rainfall conditions. In contrast, based on data from 218 GPS-monitored juveniles, aged 8-10 months, we found that local landscape composition and seasonal rainfall deficits had interacting effects on winter body mass. The juveniles were generally heavier with higher proportions of meadows in their predicted home range (mean 0.4 kg +/- 0.2 SE), but this difference disappeared following dry summers (SPI < 1). Juveniles with low access to summer crops (e.g., 5%) were significantly lighter following dry autumns (mean -0.9 kg +/- 0.3 SE), whereas this was not the case for those with higher access to these crops (e.g., 20%). Although populations of large herbivores may respond to harsh climatic conditions by exploiting anthropogenic resources, our results suggest that any compensation effects are strongly dependent on the type of anthropogenic land use and the timing of rainfall deficits, calling for explicitly considering how local climatic conditions and human practices may interact in shaping individual performance and, so, population dynamics
Bronze Age copper supply in Mediterranean France: first results from lead isotope and chemical analyses of hoarded metalwork
No full textInternational audienceCopper supply networks in southern France are analysed on the basis of a study of five hoards of metal objects dating from the end of the Early Bronze Age (c. 17th-16th BCE) to the end of the Late Bronze Age (c. 9th BCE). A total of 73 inductively coupled plasma-optical emission spectroscopy elemental analyses were performed and 48 objects belonging to the different groups that could be identified from the elemental compositions were targeted for lead isotope analysis (multicollector-inductively coupled plasma mass spectrometry). The results clearly show that the same source was used for the various objects in each hoard, but that copper from different origins was used depending on the period. This reveals evolving supply networks that can be linked to the cultural interactions observed during this period. Towards the end of the Early Bronze Age or the beginning of the Middle Bronze Age (c. 17th-16th BCE), axe-ingots were imported into southern France along the Rhone corridor. The origin of the copper from which they are made could potentially be the Vosges massif. On the other hand, one of the major contributions of this study is to have demonstrated the use of copper originating from the Southeastern Alps during a late phase of the Middle Bronze Age and up to the Late Bronze Age (c. 14th-11th BCE). A form of packaging for this Alpine copper was as pick-ingots, and it was probably in this form that it arrived in southern France. This network was interrupted around the 9th century BCE and the populations of southern France returned to the exploitation of local minerals (Cabrières-Péret district). This research highlights the link between trade networks and cultural dynamics, showing that the circulation of raw materials also helps strengthen relations between communities
A Greedy Constructive Heuristic for Executing Cloud-based Workflows with Data Confidentiality Restrictions
No full textInternational audienceOver the past decade, many scientific experiments have shifted from on-premise environments to the cloud. While clouds offer flexibility, scalability, and costeffectiveness, security, and confidentiality remain an issue. This is particularly true when experiments are modeled as workflows and executed using cloud-based workflow systems. These systems typically use multiple virtual machines (VMs) and shared cloud storage to execute the workflow and store the files generated during workflow execution. If these files are accessed by malicious users, they could reveal sensitive information about the workflow's results or structure. To mitigate these risks, data dispersion and techniques such as encryption can be employed, but they need to be carefully integrated into the workflow scheduling process. For example, dispersing data to storage far from the processing VM may increase workflow makespan and costs. In this manuscript, we propose CYCLOPS, an approach designed to execute workflows efficiently in clouds while addressing data confidentiality requirements. CYCLOPS incorporates a mathematical model and a Greedy Constructive Heuristic to optimize workflow scheduling. We evaluated the approach using both synthetic and real-world workflows. The results demonstrate that CYCLOPS enhances workflow execution efficiency while ensuring that data confidentiality is maintained
Approche dispositionnelle et affective de l’intention d’abandonner en doctorat.
No full textInternational audienceThis study examines the profiles of doctoral students who intent to drop out oftheir thesis and those who intent to persevere. Very few studies have explored the influence ofpersonality on doctoral students’ motivation. Thus, a longitudinal study was carried outamong doctoral students in the humanities and social sciences from 2020 (T1) to 2021(T2).Doctoral students were asked to complete a personality test questionnaire. Two additionalmeasures were collected: a measure of their sense of self-efficacy in terms of research skills,and a measure of their level of anxiety and depression. The aim was to determine whetherdoctoral students' stated intention to dropout (vs. persist) could be linked to personalityprofiles, while also considering their emotional experience and sense of self-efficacy. Theresults showed the relevance of discriminating doctoral students according to their intentionsto persist or to drop out, in order to gain a better understanding of the doctoral experience.The results indicated that the personality dimensions significantly involved in the intention todrop out are not the same as those involved in the intention to persist. Also, it appeared thatthe doctoral experience tends to deteriorate over time regardless of whether doctoral studentsintend to abandon or continue. However, the reasons for this deterioration differ according tothe group of doctoral students considered. Overall, this study highlights the need for a morepersonalized approach to doctoral students' intention to drop out or persistence. In thisrespect, suggestions for universities, doctoral schools and thesis supervisors are provided tohelp them reflect on how to support doctoral students.Cette étude s’intéresse aux profils des doctorants qui souhaitent abandonner leurthèse et ceux qui souhaitent au contraire persévérer. Très peu d’études se sont intéressées àl’influence de la personnalité sur la motivation des doctorants. Dans cet objectif, une étudelongitudinale a été réalisée auprès de doctorants en sciences humaines et sociales de 2020(T1) à 2021(T2). Les doctorants ont été soumis à un questionnaire de personnalité, unemesure de leur sentiment d’auto-efficacité en matière de compétences de recherche, et unemesure de leur niveau d’anxiété et de dépression. L’objectif était de déterminer si l’intentiond’abandon (vs. de persistance) déclarée par les doctorants pouvait être mise en lien avec desprofils de personnalités, tout en considérant aussi leur vécu émotionnel et leur sentimentd’auto-efficacité. Les résultats ont montré l’intérêt de discriminer les doctorants selon leursintentions de persister ou d’abandonner, afin de mieux comprendre l'expérience du parcoursdoctoral. Les dimensions de la personnalité impliquées significativement dans l’intentiond’abandonner ne sont pas les mêmes que celles impliquées dans l’intention de persister. Deplus, que les doctorants souhaitent abandonner ou persister, il apparaît que l'expérience dudoctorat tend à se dégrader avec le temps, mais que les raisons de cette dégradation diffèrentselon le groupe de doctorants considéré. Dans l’ensemble, cette étude met en lumière quel’approche de l’intention d’abandonner ou de persister des doctorants gagnerait à êtrepersonnalisée. Des pistes destinées aux universités, écoles doctorales et directeurs de thèsesont à cet égard fournis pour alimenter la réflexion sur l’encadrement des doctorants.Mots clés : Intention d’abandonner, Doctorants, Personnalité, Auto-efficacité, Éducation
Petite généalogie d’un sacerdote thébain
No full textInternational audiencePublication d’un fragment de statue ayant appartenu à un certain Paamon, datable entre la XXXe dynastie et l’époque ptolémaïque. Outre ses titres qui assurent une origine thébaine, les bribes d’inscription de l’appui dorsal livrent une petite généalogie du personnage sur six générations