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Turbo égalisation des constellations tournées pour les systèmes acoustiques sous-marins
No full textInternational audienceThe available bandwidth of the underwater acoustic channel is severely limited. Therefore, it is of interest to use modulations with high spectral efficiency, such as rotated constellations. These constellations offer better theoretical performance than conventional constellations. However, in practice, when conventional equalization algorithms are used for a system employing rotated constellations, the theoretical gain is not fully achieved. To address this issue, this paper proposes a new turbo equalization algorithm that inherently considers the characteristics of rotated signals and allows for a significant gain compared to conventional methods, as demonstrated by simulations.-Les débits des communications acoustiques sous-marines sont très limités en raison de la faible bande passante disponible. Les constellations tournées, modulations à forte efficacité spectrale, permettent d'atteindre des performances théoriques supérieures à celles des constellations conventionnelles, sans altérer l'efficacité spectrale ou énergétique du système. Cependant, en pratique, l'utilisation d'algorithmes d'égalisation conventionnels ne permet pas de bénéficier pleinement des avantages théoriques des constellations tournées. Pour résoudre ce problème, cet article propose un nouvel algorithme de Turbo-égalisation qui prend spécialement en compte les caractéristiques des signaux tournés. Nos simulations montrent que notre algorithme permet un gain significatif par rapport aux méthodes conventionnelles
Robust MILP formulations for the two-stage weighted vertex p -center problem
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N 2-methylguanosine modifications on human tRNAs and snRNA U6 are important for cell proliferation, protein translation and pre-mRNA splicing
No full textInternational audienceModified nucleotides in non-coding RNAs, such as tRNAs and snRNAs, represent an important layer of gene expression regulation through their ability to fine-tune mRNA maturation and translation. Dysregulation of such modifications and the enzymes installing them have been linked to various human pathologies including neurodevelopmental disorders and cancers. Several methyltransferases (MTases) are regulated allosterically by human TRMT112 (Trm112 in Saccharomyces cerevisiae), but the interactome of this regulator and targets of its interacting MTases remain incompletely characterized. Here, we have investigated the interaction network of human TRMT112 in intact cells and identify three poorly characterized putative MTases (TRMT11, THUMPD3 and THUMPD2) as direct partners. We demonstrate that these three proteins are active N2-methylguanosine (m2G) MTases and that TRMT11 and THUMPD3 methylate positions 10 and 6 of tRNAs, respectively. For THUMPD2, we discovered that it directly associates with the U6 snRNA, a core component of the catalytic spliceosome, and is required for the formation of m2G, the last ‘orphan’ modification in U6 snRNA. Furthermore, our data reveal the combined importance of TRMT11 and THUMPD3 for optimal protein synthesis and cell proliferation as well as a role for THUMPD2 in fine-tuning pre-mRNA splicing
Robust Virtual Sensing of Vehicle Sideslip Angle through Cross-Combination of Multiple Filters using Decision Trees Algorithm
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Assessing perceptions of open banking: The case of digital natives in France
No full textInternational audienceOpen banking relies on open bank information systems and sharing customer data with third parties. This study aims to determine how digital natives perceive open banking (OB), what fears they may have, whether there is any difference between those who already use financial technology (Fintech), such as an account aggregator, and those who do not, and how banks can encourage consumers during the transition toward OB to improve consumer trust. To study perceptions of open banking, a primary survey using structured questionnaires was conducted among 556 digital native women. A post-qualitative study involving the director of OB services at Crédit Mutuel Arkéa (France) investigated managerial implications. The results show that OB impacts the level of trust customers have in their banks, whether they use an aggregator or not. Most consumers are against their data being accessible to companies unrelated to their banks, which clearly demonstrates their stance against data sharing. The analyses of these results lead us to offer several recommendations, especially in terms of helping banks begin to leverage open systems so that consumers can have confidence in innovations like OB
Diel patterns of fin whale 20 Hz acoustic presence in Eastern Antarctic waters
No full textInternational audienceThis study presents evidence of diel patterns in fin whale ( Balaenoptera physalus ) 20 Hz acoustic presence in Eastern Antarctic waters. Passive acoustic recordings were collected at four sites in Eastern Antarctica from 2013 to 2019. A generalized linear model fitted by a generalized estimating equation was used to test the hypothesis that fin whale 20 Hz acoustic presence shows significant variation between light regimes dawn, day, dusk and night. In the Indian sector of Antarctica, at the Prydz and Southern Kerguelen Plateau sites, fin whale acoustic presence was significantly more common during the night and dawn before declining during the day and dusk periods. A different diel pattern was observed in the Pacific sector, at the Dumont d'Urville site: fin whale acoustic presence was significantly more common during the day than dusk and night periods. No diel pattern was identified at the Casey site. The identified diel patterns in the Indian sector of Eastern Antarctica correlate with previously identified diel patterns of the fin whales' prey. We suggest an indirect association between fin whale acoustic presence and foraging, with the animals more likely to produce the 20 Hz pulse during the night when not foraging and less likely to vocalize when foraging during the day
Revisiting facet nucleation under mixed mode I+III loading with T-stress and mode-dependent fracture properties
No full textInternational audienceWe study the problem of crack front segmentation into facets under mixed mode I+III loading. Discrete facet network nucleation is determined based on the match asymptotic expansion approach of the coupled criterion considering both the influence of T-stress (parallel to the initial crack front) and modedependent fracture properties. We show that considering exclusively either T-stress or mode dependent properties, facet nucleation may be more favorable than straight crack propagation but in conditions that are incompatible with experimental observations. It is only by coupling mode-dependent fracture properties with T-stress that we are able to determine configurations compatible with experimental observations for which facet nucleation is more likely to occur than straight crack propagation. These configurations depend on the T-stress magnitude and critical shear energy release rate. We thus highlight that crack front segmentation into facets is material and loading dependent phenomenon that is not related to a sole mode mixity threshold but also to T-stress magnitude and shear critical energy release rate
Extrapolation-based Prediction-Correction Methods for Time-varying Convex Optimization
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The respective contribution of cognitive control and working memory to semantic and subjective organization in aging
No full textInternational audienceOrganizing information is beneficial to episodic memory performance. Among several possible organizational strategies, two consist of organizing the information in semantic clusters (semantic organization) or self-organizing the information based on new associations that do not exist in semantic memory (subjective organization). Here, we investigated in a single study how these two organizational behaviors were underlined by different controlled processes and whether these relations were subjected to age-related differences. We tested 123 younger adults (n = 63) and older adults (n = 60) on two episodic memory tasks, one where the words were organizable and another where the words were not organizable, allowing for semantic and subjective organization, respectively. Additionally, participants were tested on three cognitive control tasks (Wisconsin Card Sorting Test, Stroop Test and Trail Making Test) and three working memory tasks (Backward Digit Span, Alpha Span and N-back test). Results revealed well-established age-related differences in terms of recall performance and organizational strategy implementation. More importantly, we found evidence that the different cognitive tests statistically yielded two different latent factors, a cognitive control factor and a working memory factor. Based on this dissociation, we found that only cognitive control contributed to semantic organization in all age groups whereas only working memory contributed to subjective organization, also in all age groups. These results shed new lights on our understanding of how controlled processes differently contribute to organizational behaviors in episodic memory
Eddy-current asymptotics of the Maxwell PMCHWT formulation for multiple bodies and conductivity levels
No full textInternational audienceIn eddy current (EC) testing applications, ECs σE (E : electric field, σ: conductivity) are induced in tested metal parts by a low-frequency (LF) source idealized as a closed current loop in air. In the case of highly conducting (HC) parts, a boundary integral equation (BIE) of the first kind under the magneto-quasi-static approximation - which neglects the displacement current - was shown in a previous work to coincide with the leading order of an asymptotic expansion of the Maxwell BIE in a small parameter reflecting both LF and HC assumptions. The main goal of this work is to generalize the latter approach by establishing a unified asymptotic framework that is applicable to configurations that may involve multiple moderately-conducting (σ = O(1)) and non-conducting objects in addition to (possibly multiply-connected) HC objects. Leading-order approximations of the quantities relevant to EC testing, in particular the impedance variation, are then found to be computable from a reduced set of primary unknowns (three on HC objects and two on other objects, instead of four per objectfor the Maxwell problem). Moreover, when applied to the Maxwell BIE, the scalings suggested by the asymptotic approach stabilize the condition number at low frequencies and remove the low-frequency breakdown effect. The established asymptotic properties are confirmed on 3D numerical examples for simple geometries as well as two EC testing configurations, namely a classical benchmark and a steam generator tube featured in pressurized water reactors of nuclear power plants