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On Completeness of Cost Metrics and Meta-Search Algorithms in $-Calculus
No full textIn the paper we define three new complexity classes for Turing Machineundecidable problems inspired by the famous Cook/Levin's NP-complete complexityclass for intractable problems. These are U-complete (Universal complete),D-complete (Diagonalization complete) and H-complete (Hypercomputationcomplete) classes. In the paper, in the spirit of Cook/Levin/Karp, we startedthe population process of these new classes assigning several undecidableproblems to them. We justify that some super-Turing models of computation,i.e., models going beyond Turing machines, are tremendously expressive and theyallow to accept arbitrary languages over a given alphabet including thoseundecidable ones. We prove also that one of such super-Turing models ofcomputation - the \$-Calculus, designed as a tool for automatic problem solvingand automatic programming, has also such tremendous expressiveness. Weinvestigate also completeness of cost metrics and meta-search algorithms in\$-calculus
Fatigue crack growth under large scale yielding condition: a tool based on explicit crack growth
No full textFatigue crack growth under large-scale yielding condition is studied for high-temperature loading. The applied strains are so important that diffuse damage phenomena are visible as a network of micro-cracks in front of the major crack. The survey of a macroscopic cracked surface is nevertheless possible, and numerical simulations with explicit representation of this crack are carried out to evaluate crack driving forces. The proposed numerical scheme takes into account plastic wake in the course of crack growth in a 3D model. A non-local model of fatigue crack growth rate, based on partition of strain energy density into elastic and plastic terms, yields improved results as compared to classical assessment of ∆J by numerical methods
A note on Fourier eigenfunctions in four dimensions
No full textIn this note, we exhibit a weakly holomorphic modular form for use in constructing a Fourier eigenfunction in four dimensions. Such auxiliary functions may be of use to the D4 checkerboard lattice and the four dimensional sphere packing problem
Existence and uniqueness theorems for functional equations
No full textIn this paper we give simple extension and uniqueness theorems for restrictedadditive and logarithmic functional equations
Patch Locale of a Spectral Locale in Univalent Type Theory
No full textStone locales together with continuous maps form a coreflective subcategoryof spectral locales and perfect maps. A proof in the internal language of anelementary topos was previously given by the second-named author. This proofcan be easily translated to univalent type theory using resizing axioms. Inthis work, we show how to achieve such a translation without resizing axioms,by working with large, locally small, and small complete frames with smallbases. This turns out to be nontrivial and involves predicative reformulationsof several fundamental concepts of locale theory
Vers une plateforme sémantique pour l'apprentissage adaptatif et collaboratif en ligne
No full textsoumission à EpisciencesIn the world of e-learning, learning systems have sought to adapt the user's profile and the content offered to them. However, from the point of view of collaboration between learners based on adaptation to the learner profile, this adaptation has not been sufficiently explored as an important aspect of the e-learning process. Adaptation will allow users with similar or very similar profiles to be grouped together to learn in harmony while maintaining motivation and commitment to learning. This should increase the success rate of learners. This will also allow us to reuse learning paths with good success rates for future recommendations to users with the same profile. In this paper, we focus on this aspect and propose a learning system that controls learning paths adapted to the users' profile and that allows collaborative learning of users in a synchronous way. After an overview of the existing work in the field of adaptive e-learning, we propose an architecture for the piloting of this type of collaborative adaptive learning based on ontologies and orchestrated by a multi-agent system. The latter is responsible for the piloting of learning paths, the recommendation of paths in collaborative or non-collaborative mode through communication between the different agents involved, and the management of events captured by the system.Dans le monde de la formation en ligne, les systèmes d'apprentissage ont cherché à proposer un contenu adapté à tout utilisateur selon son profil.Cette adaptation a comme objectif général de permettre à l'apprenant de tirer le meilleur parti du contenu exposé des ressources d'apprentissage.Cependant, du point de vue de la collaboration entre apprenants selon l'adaptation au profil des apprenants, cette adaptation n'a pas été suffisamment explorée comme un aspect important du processus d'apprentissage en ligne.L'adaptation va permettre de grouper des utilisateurs de profil similaire ou très proche pour apprendre en harmonie tout en gardant la motivation et l'engagement nécessaire afin d'augmenter le taux de réussite des apprenants. Cet état de fait doit permettre aussi de réutiliser certains parcours d'apprentissage avec de bons taux de réussite pour de futures recommandations aux utilisateurs ayant le même profil. Dans cet article, nous mettons l'accent sur cet aspect et proposons un système d'apprentissage qui recommande des parcours d'apprentissage adaptés au profil des utilisateurs et qui permet un apprentissage collaboratif des utilisateurs de façon synchrone. Après un tour d'horizon de l'existant dans le domaine de l'apprentissage adaptatif en ligne, nous proposerons une architecture pour le pilotage de ce type d'apprentissage adaptatif collaboratif. Cette solution est fondée sur des ontologies et orchestrée par un système multi-agents. Ce dernier est responsable du pilotage des parcours d'apprentissage, de la recommandation de parcours en mode collaboratif ou non par le biais d'une communication entre les différents agents intervenants et de la gestion des événements captés par le système
A Hybrid Algorithm Based on Multi-colony Ant Optimization and Lin-Kernighan for solving the Traveling Salesman Problem
No full textIn this article, a hybrid heuristic algorithm is proposed to solve the Traveling Salesman Problem (TSP). This algorithm combines two main metaheuristics: optimization of multi-colony ant colonies (MACO) and Lin-Kernighan-Helsgaun (LKH). The proposed hybrid approach (MACO-LKH) is a so-called insertion and relay hybridization. It brings two major innovations: The first consists in replacing the static visibility function used in the MACO heuristic by the dynamic visibility function used in LKH. This has the consequence of avoiding long paths and favoring the choice of the shortest paths more quickly. Hence the term insertion hybridization. The second innovation consists in modifying the pheromone update strategy of MACO by that of the dynamic λ-opt mechanisms of LKH in order to optimize the solutions generated and save in execution time, hence the relay hybridization. The significance of the hybridization, is examined and validated on benchmark instances including small, medium, and large instance problems taken from the TSPlib library. The results are compared to four other state-of-the-art metaheuristic approaches. It results in that they are significantly outperformed by the proposed algorithm in terms of the quality of solutions obtained and execution time
Impact of Image Enhancement Methods on Automatic Transcription Trainings with eScriptorium
No full textThis study stems from the Desenrollando el cordel (Untangling the cordel) project, which focuses on 19th-century Spanish prints editing. It evaluates the impact of image enhancement methods on the automatic transcription of low-quality documents, both in terms of printing and digitisation. We compare different methods (binarisation, deblur) and present the results obtained during the training of models with the Kraken tool. We demonstrate that binarisation methods give better results than the other, and that the combination of several techniques did not significantly improve the transcription prediction. This study shows the significance of using image enhancement methods with Kraken. It paves the way for further experiments with larger and more varied corpora to help future projects design their automatic transcription workflow
Communication en matière de sécurité routière et comportement des usagers de la route : le rôle du risque perçu
No full textThe purpose of this article is to show the extent to which road safety communication influences users’ behavior. To achieve this, we collected data through a survey over a five-month period in between February and June 2019. Then exploratory factor analysis and confirmatory factor analysis were carried out, and finally structural equations were used to test the hypotheses. Results show that communication has a direct effect on road users’ behavior, communication influences perception of bodily risk which in turn does not affect road users’ behavior, communication does not affect equipment risk which in turn influences road users’ behavior. Results also show that the strength of the relationships among the above-mentioned variables depends upon user’s location, user type and user’s age.L’objectif de cet article est de montrer dans quelle mesure la communication en sécurité routière influe sur le comportement des usagers de la route. Pour atteindre cet objectif, nous avons collecté les données à partir d’une enquête par questionnaire sur une période de cinq mois, de février à juin 2019. Ces données ont fait l’objet d’une analyse factorielle exploratoire et d’une analyse factorielle confirmatoire ; des équations structurelles ont également été mobilisées pour tester les hypothèses que nous nous sommes fixées. Les résultats montrent que la communication a un effet direct sur le comportement des usagers de la route ; elle influe sur la perception du risque corporel, mais ce dernier n’a pas d’effet sur le comportement ; la communication n’influe pas sur la perception du risque matériel qui pour sa part a un effet sur le comportement. Les résultats montrent également que la force du lien entre ces variables dépend de la ville de résidence de l’usager, de sa nature et de son âge
New Technologies, Training Initiatives and the Future of Manuscript Studies
No full textWe are standing at the edge of a major transformation in manuscript studies.Digital surrogates, Digital Humanities analyses and the rise of new scientificanalytical technologies proliferate across universities, libraries and museums.They change the way we consult, research and disseminate historical manuscriptsto reveal hitherto unknown, and unknowable, information. This article looks athow the field can best integrate these transformations. Concentrating ontraining programmes for advanced students as a way of reimagining the field, itprovides concrete advice for the future of manuscript studies, arguing that theexistence of manuscript studies as removed from Digital Humanities and heritagescience is becoming more and more artificial and detrimental to the future ofthe field.Comment: 5 figure