Portail HAL des publications du LIRMM
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OntoPortal code LIRMM branch
No full textMaster repository for OntoPortal code LIRMM branch used as baseline for multiple repositories such as AgroPortal, SIFR BioPortal, EarthPortal, LovPortal
A Toolchain for Deterministic Parallelism on an Embedded Bare-metal Platform
No full textInternational audienceBare-metal platforms, as well as many other platforms, can make great gains in performance through parallel programs. However, running such kind of programs is often harder on bare-metal platforms. This leaves the management of parallelism on bare-metal platforms under the purview of the programmer, thus increasing the program complexity. Furthermore, this also makes the program specific to the target baremetal platform once ported. This paper presents a set of tools used to build and execute parallel programs on custom baremetal platforms as painlessly as possible. The proposed toolchain behaves like a regular compilation toolchain, taking standard C OpenMP code as input and building platform-specific, parallel bare-metal binaries as output. We evaluated the behavior of standard C OpenMP code executed on our platform both in terms of correctness and in terms of speedup. Our observations show that it is possible to preserve the performance speedup of parallel execution on a bare-metal platform, without having to modify the program source code. Furthermore, these changes allow programs to exhibit some degree of determinism, which is apropos for bare-metal platforms
Population structure of the swordfish, Xiphias gladius, across the Indian Ocean using next-generation sequencing
No full textInternational audienceSwordfish (Xiphias gladius) is of significant economic importance as it is the second most exploited billfish in the Indian Ocean. While the Indian Ocean Tuna Commission (IOTC) considers swordfish to be a single panmictic population in the Indian Ocean, several studies have examined the potential for spatial variations within this highly migratory species with conflicting results, including emerging evidence that population structuring does indeed exist within swordfish. These findings therefore raise questions about the current guidelines for management adopted by the IOTC. In the present study, we address questions about the genetic structuring of swordfish in the Indian Ocean through the analysis of three datasets: (i) neutral SNPs, (ii) with, and (iii) only SNPs under potential selection identified from 1694 swordfish originating from 24 distinct locations across the Indian Ocean. A discriminant analysis of principal components showed the presence of two swordfish subpopulations in the Indian Ocean in the north and the south and was confirmed by admixture methods. This genetic differentiation may be explained by a chromosomal inversion, indicating that both populations could be demographically connected but remain differentiated by this structural variant
Query-driven Qualitative Constraint Acquisition
No full textInternational audienceMany planning, scheduling or multi-dimensional packing problems involve the design of subtle logical combinations of temporal or spatial constraints. Recently, we introduced GEQCA-I, which stands for Generic Qualitative Constraint Acquisition, as a new active constraint acquisition method for learning qualitative constraints using qualitative queries. In this paper, we revise and extend GEQCA-I to GEQCA-II with a new type of query, universal query, for qualitative constraint acquisition, with a deeper query-driven acquisition algorithm. Our extended experimental evaluation shows the efficiency and usefulness of the concept of universal query in learning randomly-generated qualitative networks, including both temporal networks based on Allen’s algebra and spatial networks based on region connection calculus. We also show the effectiveness of GEQCA-II in learning the qualitative part of real scheduling problems
Assessing the feasibility of Micro frontend architecture in native mobile app development
No full textInternational audienceSince their introduction, mobile application development has become complex and now rivals web app development. The primary factor contributing to this complexity is their monolithic architecture: a mobile application is still deployed as a single unit. In contrast, web applications have adopted modular architectures such as Microservice or Micro FrontEnd (MFE). This last approach divides development into teams, each responsible for an MFE corresponding to a specific software feature. Our study examines the adoption of the MFE architecture on native mobile platforms. This paper discusses: i) how MFE can be adapted to current native mobile platforms; ii) the limitations of adapting MFE architecture on mobile; and iii) the challenges MFE introduces to mobile application development. Despite challenges in composing mobile MFEs post-deployment, our research highlighted maintaining a static development-side composite is feasible, albeit with a loss of flexibility. This allows team separation and independent feature development, though technological agnosticism isn't achieved
A machine learning based approach for generating point sketch maps from qualitative directional information
No full textInternational audiencePeople often use qualitative relations to describe locations or directional information, especially in written communication, such as ‘the restaurant is located at the southeast corner of the square’. However, when a large number of spatial entities are involved, qualitative relations alone are not intuitive enough for people to understand a spatial configuration. In fact, many applications, e.g. pertaining to sharing travel experiences, use sketch maps, i.e. maps focusing on the main features of an area whilst abstracting exact scale measurements, to help demonstrate abstract qualitative relations with more intuitive geometric points. Current approaches for generating point sketch maps from qualitative spatial relations require a high level of expertise, face inherent difficulties with efficiently processing large-scale data in bulk, and are vulnerable to inaccurate or conflicting information contained in qualitative data. To address these limitations, by incorporating machine learning techniques, we propose to translate the problem into an optimization problem of data reconstruction, enabling a novel end-to-end approach for generating point sketch maps from qualitative directional relations in bulk. Experiments on real-world datasets show that the proposed approach has very high accuracy and is robust even with a large portion of inaccurate or incomplete information
Computing with oscillators from theoretical underpinnings to applications and demonstrators
No full textInternational audienceNetworks of coupled oscillators have far-reaching implications across various fields, providing insights into a plethora of dynamics. This review offers an in-depth overview of computing with oscillators covering computational capability, synchronization occurrence and mathematical formalism. We discuss numerous circuit design implementations, technology choices and applications from pattern retrieval, combinatorial optimization problems to machine learning algorithms. We also outline perspectives to broaden the applications and mathematical understanding of coupled oscillator dynamics
Counting overlapping pairs of strings
No full text2 documents: abstract and slides presention for SeqBIM 2025 ; Résumé et présentation pour SebBIM 2025International audienceA word overlaps a word if a suffix of equals a prefix of . The shared suffix-prefix is called a border for the ordered pair of words (note that other authors call this a right border, see [1]). If has no border it is said unbordered. These notions generalize to pairs of words, the well studied notions of border, bordered and unbordered words, that were originally defined for single words. Example: Consider the binary alphabet {a, b} and the following three words denoted by u, v, w: abaaa, aaabb, and abbbb. The pairs (u, v) and (v, w) both have a longest border of length 3, but (u, v) has 3 distinct non empty borders aaa, aa, and a, while (v, w) has only one abb. The pairs (v, u) and (w, v) have no borders, which illustrates the asymmetry of this notion.Overlapping and unbordered words are central in many applications: bioinformatics, pattern matching, code design, or word statistics, among others.Other authors have proposed to encode the starting position of such overlaps in a binary vector called a correlation [2]. In our example, the correlation of the pair (u, v) is 00111, while that of (v, w) is 00100. For any word z, the correlation of (z, z) is called the autocorrelation of z. Clearly, multiple pairs can have the same correlation, and hence there are less correlations of length n than pairs of words of length n. Recently, Gabric [1] gave three recurrences to count bordered, mutually bordered, mutually unbordered pairs of words of length n over a k-ary alphabet [1]. In his conclusion, he raised challenging open questions: 1/ count the number of pairs having the longest border of length i (with i satisfying 0 < i < n), and 2/ what is the expected length of the longest border of a pair of words? Here, we exhibit two solutions to compute the population size of any correlation, that is the number of pairs of words having the same correlation. For this, we exploit two recurrences to compute the population size of autocorrelations [2, 3]. With this in hand, we derive a formula for the abovementioned open question 1/ and show that the expected length of the longest border of words of length n asymptotically diverges (open question 2/). Besides this, we provide bounds for the asymptotic of the population ratio of any correlation, which extend the result known for autocorrelations [2].An article presenting these results is available on ArXiV online [4].</p
The Development of a 7-DoF Humanoid Arm for Driving Using a Task-Driven Design Method
No full textInternational audienceIn this article, a new 7-DoF humanoid arm that can operate a steering wheel anthropomorphically, and a task-based design method for such redundant manipulators that work with loads in constrained spaces are devised. The latter consists of a controller-integrated optimization method (COM) for structural parameter optimization, and a combinatorial filtration method (CFM) for actuator selection. The COM is based on kinetostatic analysis and implemented through the covariance matrix adaptation evolutionary strategy (CMA-CS). In the optimization, a collision-free control (CFC) method is integrated for the accurate workspace evaluation and the manipulability index for characterizing the kinematic performance. The CFM is based on the results of the COM and a dynamic analysis. In actuator selection, a library of available candidate motors and reducers is constructed for global selection based on the design objectives and the characteristics for more accurate joint parameters. The effectiveness of CFC in structural parameter optimization is verified in the CFM. Thus, a 7-DoF humanoid arm for driving is achieved; its performance is evaluated in real-world experiments to assess the validity of the design
Upper-Limb and Low-Back Load Analysis in Workers Performing an Actual Industrial Use-Case with and without a Dual-Arm Collaborative Robot
No full textInternational audienceIn the Industry 4.0 scenario, human–robot collaboration (HRC) plays a key role in factories to reduce costs, increase production, and help aged and/or sick workers maintain their job. The approaches of the ISO 11228 series commonly used for biomechanical risk assessments cannot be applied in Industry 4.0, as they do not involve interactions between workers and HRC technologies. The use of wearable sensor networks and software for biomechanical risk assessments could help us develop a more reliable idea about the effectiveness of collaborative robots (coBots) in reducing the biomechanical load for workers. The aim of the present study was to investigate some biomechanical parameters with the 3D Static Strength Prediction Program (3DSSPP) software v.7.1.3, on workers executing a practical manual material-handling task, by comparing a dual-arm coBot-assisted scenario with a no-coBot scenario. In this study, we calculated the mean and the standard deviation (SD) values from eleven participants for some 3DSSPP parameters. We considered the following parameters: the percentage of maximum voluntary contraction (%MVC), the maximum allowed static exertion time (MaxST), the low-back spine compression forces at the L4/L5 level (L4Ort), and the strength percent capable value (SPC). The advantages of introducing the coBot, according to our statistics, concerned trunk flexion (SPC from 85.8% without coBot to 95.2%; %MVC from 63.5% without coBot to 43.4%; MaxST from 33.9 s without coBot to 86.2 s), left shoulder abdo-adduction (%MVC from 46.1% without coBot to 32.6%; MaxST from 32.7 s without coBot to 65 s), and right shoulder abdo-adduction (%MVC from 43.9% without coBot to 30.0%; MaxST from 37.2 s without coBot to 70.7 s) in Phase 1, and right shoulder humeral rotation (%MVC from 68.4% without coBot to 7.4%; MaxST from 873.0 s without coBot to 125.2 s), right shoulder abdo-adduction (%MVC from 31.0% without coBot to 18.3%; MaxST from 60.3 s without coBot to 183.6 s), and right wrist flexion/extension rotation (%MVC from 50.2% without coBot to 3.0%; MaxST from 58.8 s without coBot to 1200.0 s) in Phase 2. Moreover, Phase 3, which consisted of another manual handling task, would be removed by using a coBot. In summary, using a coBot in this industrial scenario would reduce the biomechanical risk for workers, particularly for the trunk, both shoulders, and the right wrist. Finally, the 3DSSPP software could be an easy, fast, and costless tool for biomechanical risk assessments in an Industry 4.0 scenario where ISO 11228 series cannot be applied; it could be used by occupational medicine physicians and health and safety technicians, and could also help employers to justify a long-term investment