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Existential Definability over the Subword Ordering
No full textWe study first-order logic (FO) over the structure consisting of finite wordsover some alphabet , together with the (non-contiguous) subword ordering. Interms of decidability of quantifier alternation fragments, this logic iswell-understood: If every word is available as a constant, then even the (i.e., existential) fragment is undecidable, already for binaryalphabets . However, up to now, little is known about the expressiveness ofthe quantifier alternation fragments: For example, the undecidability proof forthe existential fragment relies on Diophantine equations and only shows thatrecursively enumerable languages over a singleton alphabet (and some auxiliarypredicates) are definable. We show that if , then a relation isdefinable in the existential fragment over with constants if and only if itis recursively enumerable. This implies characterizations for all fragments: If , then a relation is definable in if andonly if it belongs to the -th level of the arithmetical hierarchy. Inaddition, our result yields an analogous complete description of the-fragments for of the pure logic, where the words of are not available as constants
Finitary Simulation of Infinitary -Reduction via Taylor Expansion, and Applications
No full textOriginating in Girard's Linear logic, Ehrhard and Regnier's Taylor expansionof -terms has been broadly used as a tool to approximate the terms ofseveral variants of the -calculus. Many results arise from aCommutation theorem relating the normal form of the Taylor expansion of a termto its B\"ohm tree. This led us to consider extending this formalism to theinfinitary -calculus, since the version ofthis calculus has B\"ohm trees as normal forms and seems to be the idealframework to reformulate the Commutation theorem. We give a (co-)inductive presentation of . We definea Taylor expansion on this calculus, and state that the infinitary-reduction can be simulated through this Taylor expansion. The targetlanguage is the usual resource calculus, and in particular the resourcereduction remains finite, confluent and terminating. Finally, we state thegeneralised Commutation theorem and use our results to provide simple proofs ofsome normalisation and confluence properties in the infinitary-calculus
Dynamic Cantor Derivative Logic
No full textTopological semantics for modal logic based on the Cantor derivative operatorgives rise to derivative logics, also referred to as -logics. Unlike logicsbased on the topological closure operator, -logics have not previously beenstudied in the framework of dynamical systems, which are pairs consisting of a topological space equipped with a continuous function. We introduce the logics , and and show that they all have the finite Kripke model property and aresound and complete with respect to the -semantics in this dynamical setting.In particular, we prove that is the -logic of all dynamictopological systems, is the -logic of all dynamictopological systems, and is the -logic of all dynamic topologicalsystems based on a scattered space. We also prove a general result for the casewhere is a homeomorphism, which in particular yields soundness andcompleteness for the corresponding systems , and. The main contribution of this work is the foundation of a generalproof method for finite model property and completeness of dynamic topological-logics. Furthermore, our result for constitutes the first steptowards a proof of completeness for the trimodal topo-temporal language withrespect to a finite axiomatisation -- something known to be impossible over theclass of all spaces.Comment: Extended version of the paper in Computer Science Logic (CSL) 2022 Proceeding
Santé bucco-dentaire, petite enfance et précarité : une analyse des freins et des leviers à l’accès aux soins à travers le vécu des familles
No full textOral health is a relevant issue in public health due to the frequency of oral diseases and their impacts on health, social and professional insertion. Most of these affections could be avoided with healthy behaviors and easier use of care. However, social inequalities in health and access to care are present from early childhood. Prevention actions and support in the care pathway adapted to vulnerable populations are necessary in order to improve partnership with families, prevention and access to care from early childhood. This study aims to explore the representations about oral health and oral care from parents of children aged from 1 to 6 years old identified as being in a precarious situation and living in Dijon and its conurbation.La santé bucco-dentaire est un enjeu majeur de santé publique en raison de la fréquence des affections et de son impact sur la santé générale, la qualité de vie et l’insertion sociale. La plupart des affections seraient évitables par le biais de l’adoption de comportements favorables à la santé ainsi que par un recours aux soins facilité. Or des inégalités sociales en termes de santé bucco-dentaire et de recours aux soins sont présentes dès la petite enfance. Des actions de prévention et d’accompagnement dans le parcours de soins adaptées aux populations en situation de précarité sont donc nécessaires afin d’améliorer le partenariat avec les familles et la prévention et l’accès aux soins dès la petite enfance. Cette étude vise à explorer le rapport à la santé et aux soins bucco-dentaires de parents d’enfants de 1 à 6 ans identifiés en situation de précarité résidant dans l’agglomération dijonnaise
Operadic categories as a natural environment for Koszul duality
No full textThis is the first paper of a series which aims to set up the cornerstones ofKoszul duality for operads over operadic categories. To this end we single outadditional properties of operadic categories under which the theory ofquadratic operads and their Koszulity can be developped, parallel to thetraditional one by Ginzburg and Kapranov. We then investigate how these extraproperties interact with discrete operadic (op)fibrations, which we use as apowerful tool to construct new operadic categories from old ones. We payparticular attention to the operadic category of graphs, giving a fulldescription of this category (and its variants) as an operadic category, andproving that it satisfies all the additional properties. Our present work provides an answer to a question formulated in Loday's lasttalk in 2012:``What encodes types of operads?''. In the second and third papersof our series we continue Loday's program by answering his second question:``How to construct Koszul duals to these objects?'', and proving Koszulity ofsome of the most relevant operads.Comment: 46 pages. Final versio
Homogeneous superstrings with retract
No full textAny complex-analytic supermanifold whose retract is diffeomorphic to the complex projective superline (superstring) is, up to a diffeomorphism, either a member of a 1-parameter family or one of 9 exceptional supermanifolds. I singled out the homogeneous of these supermanifolds and described Lie superalgebras of vector fields on them
Efficient Computation of Redundancy Matrices for Moderately Redundant Truss and Frame Structures
No full textLarge statically indeterminate truss and frame structures exhibit complexload-bearing behavior, and redundancy matrices are helpful for their analysisand design. Depending on the task, the full redundancy matrix or only itsdiagonal entries are required. The standard computation procedure has a highcomputational effort. Many structures fall in the category of moderatelyredundant, i.e., the ratio of the statical indeterminacy to the number of allload-carrying modes of all elements is less one half. This paper proposes aclosed-form expression for redundancy contributions that is computationallyefficient for moderately redundant systems. The expression is derived via afactorization of the redundancy matrix that is based on singular valuedecomposition. Several examples illustrate the behavior of the method forincreasing size of systems and, where applicable, for increasing degree ofstatical indeterminacy
Potentiel des biochars à base de résidus agricoles pour le traitement des eaux usées domestiques par filtres à flux verticaux plantés d'Echinochloa pyramidalis
No full textVersion finale de l'article publié par la revue Environnement, Ingénierie & Développement EIDThe treatment of domestic wastewater by vegetated filters is proposed as an alternative better suited to the socio-economic conditions of developing countries. The use of biochar in these filters in partial or total substitution of conventional filter substrate was the main aim of the present study. The effectiveness of three biochars produced from three crop wastes (Corn cobs, coconut shells and palm nut shells) in improving the purification performance of vertical flow filters vegetated with antelope grass was studied. The experimental set-up consisted of three biochar filters plus a control replicated thrice. The filters were supplied at a hydraulic loading rate of 142 l/m2/jr. The physi-co-chemical characteristics of the water were measured 30 and then 60 days from the beginning of the test; the physical growth parameters of randomly selected plants were measured weekly between the 30th and the 60th day, i.e. 4 times. The results reveal an increase in pH, an improvement in the reduction of nitrogen, iron, phosphorus, and microbes content effluents from biochar filters compared to those from conventional sand filters. Overall, the corn cob biochar filter showed better results after two months. It remains important for future studies to monitor the parameters over a longer period and to test the effect of the combination of the three biochars in one filter.Le traitement des eaux usées domestiques par filtres plantés est proposé comme une alternative adaptée aux conditions socio-économiques des pays en voie de développement. L’utilisation du biochar dans ces filtres en substitution partielle ou totale des massifs filtrants classiques était au centre de la présente étude. L’efficacité épuratoire de trois biochars produits à partir de chacun des trois résidus végétaux (les rafles de maïs, les coques de noix de coco, et les coques de noix de palmiste) pour l’amélioration des performances épuratoires des filtres à flux vertical plantés de roseaux a été étudiée ici. Le dispositif expérimental était constitué de trois filtres à biochars répliqués trois fois et de trois filtres té-moins alimentés à 142 l/m2/jr. Les caractéristiques physico-chimiques des eaux ont été mesurées à 30 puis 60 jours depuis le début de l’essai ; les paramètres physiques de croissance des plantes mesurées toutes les semaines entre le 30e et le 60e jour soit 4 fois. Les résultats révèlent une augmentation du pH, une amélioration de la réduction de la teneur en azote, fer, phosphore et des microbes dans les filtres à biochar comparé aux filtres à sable classiques. Globalement, le filtre avec biochar de rafles de maïs a permis d’obtenir de meilleurs résultats au bout de deux mois. Il reste opportun pour les prochaines études de faire le suivi des paramètres sur une plus longue durée et de tester l’effet de la combinaison des trois biochars
Développement d’indicateurs de mesure de la variabilité d’utilisation du transport en commun à partir de données de cartes à puce
No full textTransit ridership varies over time, within the behaviour of a same user, and from one user to another. These variations make it difficult to adjust service and demand forecasting models, potentially leading to additional operating costs and a non-optimal allocation of vehicles on the network. However, the growing availability of longitudinal and individualized data now allows to better understand travel behaviour. In particular, this paper benefits from smart card data from the OPUS system of Montreal, Canada. More than 429 million validations, made by nearly 2 million cards, are mined to investigate transit use variability at a totally disaggregated level over a one-year period. Four indicators are proposed to measure several types of variations: trip dispersion among the users, variability of the frequency of use, temporal variance of the monthly number of trips and spatial diversity of the boarding locations. These indicators are applied to evaluate the regularity of 10 distinct groups of cards defined by their fare composition. Because of the sensitivity of statistical tests on sample size, an effect size analysis is provided to better quantify the magnitude of the differences between the groups. The results reveal relationships between transit use and the typeof product used. Both annual and monthly pass users are found to be regular and frequent passengers, whereas ticket book users are rather occasional travellers. Moreover, variability tends to increase with the number of different products used during the year.L’achalandage du transport en commun varie dans le temps, au sein du comportement d’un même usager, mais aussi d’un usager à l’autre. Ces variations rendent difficile l’ajustement des services et des modèles de prévision de la demande, conduisant potentiellement à des coûts d’opération supplémentaires et à une affectation non optimale des véhicules sur le réseau. Toutefois, la disponibilité croissante de données longitudinales et individualisées permet désormais de mieux comprendre la variabilité des comportements de déplacement. Cet article bénéficie ainsi de données de cartes à puce provenant du système OPUS de Montréal, Canada. Plus de 429 millions de validations, réalisées par près de 2 millions de cartes, sont exploitées pour étudier la variabilité d’utilisation du transport en commun à un niveau totalement désagrégé sur une période d’un an.Quatre indicateurs sont proposés afin de mesurer plusieurs types de variations : la dispersion des déplacements parmi les usagers, la variabilité de la fréquence d’utilisation, la variance temporelle du nombre de déplacements par mois et la diversité spatiale des lieux d’embarquement. Ces indicateurs sont appliqués pour comparer la régularité de dix groupes de cartes distincts définis en fonction de leur composition tarifaire. Face aux limites des tests statistiques traditionnels, sensibles à la taille de l’échantillon, la notion de taille d’effet est introduite pour mieux quantifier l’importance des différences observées entre les groupes. Les résultats révèlent qu’il existe une relation entre l’utilisation du transport en commun et le type de titre utilisé. Les utilisateurs d’abonnements annuels ou mensuels sont en moyenne très réguliers et fréquents, alors que les utilisateurs de carnets de tickets sont des usagers plus occasionnels. De plus, la variabilité d’usage tend à augmenter avec le nombre de titres différents utilisés durant l’année
An essay on the need to redefine economics for the sake of a human economy
No full textMore than 90 years after Lionel Robbins more or less defined the subject ofeconomics in his famous essay, it is time to redress the issue in light of recent developments and new insights. Robbins used the figure of Robinson Crusoe to define homo economicus as an agent that makes choices in conditions of scarcity. By re-reading and re-interpreting the story of Crusoe, we make more sense of the narrative when we envisage people engaged in practices by which they realize what is important to them, that is, their values. Homo economicus becomes a special case pertinent to theinstrumental economies of markets and organizations. In the so-called human economies of the home, the social, cultural, and natural world, people use the inputs that they acquire in the instrumental economies to realize what is important to them, such as families, friendships, science, art, religion, meanings. This shift in perspective will have far reaching consequence for the way economists think and theorize and enables them to connect with the value-based approach that is increasingly dominatingthe worlds of business and politics