Literatura académica sobre el tema "Modèle distribué"
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Artículos de revistas sobre el tema "Modèle distribué"
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Piet, Laurent. "Modèle d'équilibre général calculable distribué et gestion de l'eau". Économie rurale 254, n.º 1 (1999): 57–61. http://dx.doi.org/10.3406/ecoru.1999.5142.
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Bui, Marc. "Résolution du problème du multi-rendezvous à l'aide d'un modèle d'algorithme distribué". RAIRO - Operations Research 27, n.º 2 (1993): 249–64. http://dx.doi.org/10.1051/ro/1993270202491.
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Gaborit, E., G. Pelletier, P. A. Vanrolleghem y F. Anctil. "Simulation du débit de la rivière Saint-Charles, première source d’eau potable de la ville de Québec". Canadian Journal of Civil Engineering 37, n.º 2 (febrero de 2010): 311–21. http://dx.doi.org/10.1139/l09-139.
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Sur le bassin versant de la rivière Saint-Charles, il est nécessaire de mieux gérer l’eau, d’un point de vue quantitatif et qualitatif. Or la prise de décisions peut être aidée par la modélisation hydrologique. Ce travail porte sur la mise en place du modèle semi-distribué de qualité de l’eau SWAT (« soil and water assessment tool ») sur ce bassin versant urbain et relativement montagneux, et sur l’évaluation de sa capacité à simuler les débits. Cette première approche est comparée à deux autres, reposant pour l’une sur l’utilisation du modèle hydrologique global GR4J, et pour l’autre sur l’emploi d’un réseau de neurones. La quantité d’eau issue de la fonte de la neige, calculée ici par le module de fonte de SWAT, a été renseignée à ces deux autres modèles. Ce bassin présente par ailleurs de réelles difficultés pour ce type de modélisation, liées essentiellement au manque de données : quasi-absence d’information spatiale sur les précipitations et absence d’étude pédologique détaillée. Les résultats, globalement satisfaisants, montrent toutefois que la performance hydrologique résultant des trois approches est limitée par ces manques : celle utilisant SWAT davantage que les deux autres. Dans ce cas, les lacunes ne permettent pas d’utiliser le plein potentiel du modèle SWAT, dont la structure plus lourde devient un inconvénient dès que les données sont disponibles en quantité et en qualité insuffisantes pour en justifier l’exploitation, en opposition à GR4J et au réseau de neurones. Il semble donc incontournable, considérant l’importance stratégique du bassin versant de la rivière Saint-Charles pour l’approvisionnement en eau potable et le support aux activités récréatives et touristiques, que l’effort d’observation de ce territoire soit accru, afin d’y augmenter notamment les données climatologiques et pédologiques disponibles.
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Sambou, Soussou, Moussé Landing Sane, Issa Leye, Didier Maria Ndione, Seydou Kane y Mamadou Lamine Badji. "Calage et validation de SWAT sur le bassin versant du Bafing (Fleuve Sénégal) en amont de BAFING MAKANA : vers une application à la gestion du barrage de Manantali". Proceedings of the International Association of Hydrological Sciences 384 (16 de noviembre de 2021): 363–66. http://dx.doi.org/10.5194/piahs-384-363-2021.
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Abstract. En matière de Gestion des Ressources En Eau, il devient de plus en plus nécessaire de remonter à l'information pluviométrique. La modélisation est devenue ainsi un outil incontournable. Les modèles hydrologiques reposent sur le cycle hydrologique. Ils transforment les pluies en débits sur le réseau hydrographique. L'objectif de cet article est de décrire le fonctionnement hydrologique du bassin versant du Bafing (principal affluent amont du fleuve Sénégal) en amont de Bafing Makana. Le modèle hydrologique semi distribué à base physique SWAT a été choisi comme modèle de base pour calculer les hydrogrammes de crue à la station de Bafing Makana qui contrôle les entrées au barrage de Manantali. Pour représenter la topographie de la zone d'étude, un MNT de résolution 12.5 m×12.5 m a été retenu. Les observations de pluies et débits sur la période 1979–1986 (pour le calage) et 1988–1994 (pour la validation) ont été utilisées comme entrées. L'analyse de sensibilité a permis de faire apparaître les paramètres les plus significatifs du modèle. Les valeurs de ces paramètres ont été déterminées dans la phase calage puis validées dans la phase validation. La valeur du critère de Nash est de 0.71 pour la phase de calage et de 0.65 pour la phase de validation. Les résultats validés à partir du critère de Nash montrent que les valeurs prises par le critère entrent dans l'intervalle des valeurs satisfaisantes retenues pour ce critère. L'ensemble des résultats obtenus montre que le modèle hydrologique SWAT peut être utilisé dans la gestion du barrage de Manantali à l'horizon 2090.
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Fortin, J. P., R. Moussa, C. Bocquillon y J. P. Villeneuve. "Hydrotel, un modèle hydrologique distribué pouvant bénéficier des données fournies par la télédétection et les systèmes d'information géographique". Revue des sciences de l'eau 8, n.º 1 (12 de abril de 2005): 97–124. http://dx.doi.org/10.7202/705215ar.
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Les processus hydrologiques variant dans l'espace et dans le temps en fonction de la variabilité spatio-temporelle des entrées météorologiques et de l'occupation du sol ainsi que de la variabilité spatiale de la topographie et de la nature du terrain, un modèle conçu pour bénéficier des données provenant de la télédétection et des SIG a été développé. Les principaux objectifs poursuivis étaient: l'application au plus grand nombre de bassins possible, une sélection d'algorithmes permettant de tenir compte des données disponibles, un minimum d'étalonnage, la facilité de transfert d'un bassin à l'autre, la programmation des algorithmes sur micro-ordinateur avec une interface très conviviale. La structure d'écoulement à l'intérieur d'un bassin versant est obtenue de manière informatisée à partir d'une discrétisation des altitudes rencontrées dans la zone d'intérêt, en mailles carrées de dimensions données, d'où l'on tire les pentes et les orientations de chaque maille, puis le bassin versant en amont de la maille identifiée comme exutoire, le réseau hydrographique, les sous-bassins versants et, finalement, les unités hydrologiques relativement homogènes (UHRH), définies sur la base de ces sous-bassins, en les regroupant ou les divisant au besoin. Un logiciel spécifique pour ce faire a été développé: PHYSITEL. Selon la conception très modulaire adoptée pour HYDROTEL, chaque sous-modèle offre généralement plus d'une option de simulation, afin de tenir compte des données disponibles sur le bassin versant traité. Les simulations peuvent être réalisées en considérant comme unité de simulation du bilan hydrologique vertical les mailles originales constituant le bassin ou les UHRH. Des exemples de simulation des débits à l'aide du modèle HYDROTEL sur divers bassins versants situés au Canada (Québec, Ontario, Colombie-Britannique) et dans le sud de la France sont présentés. Ces simulations indiquent que les différents algorithmes du modèle réagissent bien et qu'il est possible de considérer son application sur des bassins très divers situés sous des conditions climatiques variées. Des tests plus poussés sont en cours afin de mieux cerner la sensibilité des divers algorithmes aux données d'entrée ainsi que leur interchangeabilité.
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Abdellaoui, Benyounes, Abdalaziz Merzouk, Yannick Pépin, M’Hamed Aberkan y Jean Albergel. "Simulation du bilan hydro–sédimentaire d’un barrage collinaire en zone marneuse méditerranéenne (Cas du barrage Saboun, Maroc)". Revue des sciences de l'eau 22, n.º 4 (22 de octubre de 2009): 487–504. http://dx.doi.org/10.7202/038327ar.
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Résumé La présente étude a pour objectif de suivre et de simuler les apports en eau et en sédiments dans un barrage collinaire, en utilisant un modèle hydrologique de type physique distribué permettant le calcul de l’écoulement et de l’érosion des petits bassins versants marneux. Le modèle utilisé est le modèle « Mina », transposé dans cette étude au bassin versant marneux de Saboun situé au nord-ouest du Maroc, équipé d’un petit barrage en son exutoire et d’un très petit lac collinaire dans sa partie amont. La simulation est basée sur un découpage du bassin versant en unités hydrologiques homogènes dont les valeurs des paramètres de l’infiltration sont déduites d’expérimentations de simulation de pluies à l’échelle du mètre carré. Le calage et la validation du modèle sont effectués par confrontation des sorties du modèle aux mesures hydrologiques et bathymétriques réalisées au niveau de la retenue aval entre 1997 et 1999. Cette confrontation a montré que le modèle « Mina » sous-estime l’écoulement pour des sols très humides et le surestime pour des sols secs. Cette surestimation est expliquée par la fissuration des sols marneux à l’état sec. La sous-estimation s’explique par le colmatage rapide des sols marneux à l’état humide. Pour réduire ce biais, une augmentation de la perméabilité initiale doit être appliquée pour les sols secs à faible indice d’humidité IK et une diminution de la perméabilité finale doit être appliquée pour les sols humides à fort indice d’humidité IK. Ces rectifications ont permis l’amélioration de l’estimation des volumes simulés et une meilleure estimation de l’envasement de la retenue du barrage Saboun.
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Douar, Brahim, Djemai Wassim GUETTAB y Amel Kalbaza. "Essai d’analyse du comportement des consommateurs algériens pendant la pandémie covid-19 : une analyse par la régression logistique". les cahiers du cread 38, n.º 4 (27 de febrero de 2023): 63–90. http://dx.doi.org/10.4314/cread.v38i4.3.
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Cet article a pour objectif d’analyser l’influence des facteurs économiques et comportementaux sur le comportement des consommateurs Algériens pendant la pandémie COVID-19. En effet, nous avons adopté un modèle conceptuel qui définit l’influence sur le comportement d’achat par deux types de facteurs, en l’occurrence le facteur économique et le facteur psychologique. Par la suite nous avons distribué un questionnaire, qui a été élaboré à partir du cadre conceptuel de la recherche, via internet. Nous avons collecté des données auprès des consommateurs Algériens analysées à travers la régression logistique. Nos résultats confirment l'hypothèse que la pandémie COVID-19 a induit des changements significatifs sur le comportement d'achat des consommateurs Algériens.
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Garambois, Pierre-André, Audrey Douinot, Hélène Roux y Denis Dartus. "Méthodes de régionalisation pour un modèle pluie-débit distribué et à base physique dédié aux crues éclair". La Houille Blanche, n.º 2 (abril de 2016): 71–77. http://dx.doi.org/10.1051/lhb/2016021.
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Magand, Claire, Agnès Ducharne, François Tilmant, Nicolas Le Moine, Eric Sauquet, Thibault Mathevet, Jean-Philippe Vidal y Charles Perrin. "Hybridation de réanalyses météorologiques de surface pour les zones de montagne : exemple du produit DuO sur le bassin de la Durance". La Houille Blanche, n.º 3 (junio de 2018): 77–85. http://dx.doi.org/10.1051/lhb/2018035.
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La rareté des mesures et la complexité du terrain dans les régions montagneuses engendrent d'importantes incertitudes dans les réanalyses météorologiques de surface. L'hybridation de plusieurs réanalyses est une technique efficace pour limiter ces incertitudes. Dans le bassin versant de la Durance, deux réanalyses se basant sur des réseaux de mesures et des techniques d'extrapolation différentes coexistent, SAFRAN et SPAZM. Leur comparaison montre qu'elles sont complémentaires car les précipitations de SPAZM à une résolution spatiale plus fine que celle de SAFRAN, se basent sur un plus grand nombre d'observations en haute altitude. Cependant, SPAZM ne fournit pas l'ensemble des variables atmosphériques dont un modèle hydrologique à bilans d'eau et d'énergie a besoin, contrairement à SAFRAN. L'hybridation de ces deux réanalyses a donc été effectuée. Le produit météorologique obtenu, DuO, fournit huit variables atmosphériques (température de l'air à 2 m, pluie, neige, rayonnements incidents, humidité de l'air, vent et évapotranspiration potentielle) au pas de temps horaire et à la résolution de 1 km2. DuO a été testé dans un objectif de modélisation hydrologique, avec le modèle semi-distribué CLSM (Catchment Land Surface Model). L'analyse des différentes variables de sortie (débits, stock de neige et évapotranspiration) montre que l'hybridation des deux réanalyses, valorisant les qualités respectives de SAFRAN et de SPAZM, permet une représentation plus réaliste des processus hydrologiques au sein du modèle CLSM.
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Labbas, Mériem, Flora Branger y Isabelle Braud. "Développement et évaluation d'un modèle hydrologique distribué pour des bassins périurbains - Application au bassin de l'Yzeron (150 km2)". La Houille Blanche, n.º 5 (octubre de 2015): 84–91. http://dx.doi.org/10.1051/lhb/20150059.
Texto completoTesis sobre el tema "Modèle distribué"
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Girod, Thomas. "Un modèle d'apprentissage multimodal pour un substrat distribué d'inspiration corticale". Phd thesis, Université Henri Poincaré - Nancy I, 2010. http://tel.archives-ouvertes.fr/tel-00547941.
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Le domaine des neurosciences computationnelles s'intéresse à la modélisation des fonctions cognitives à travers des modèles numériques bio-inspirés. Dans cette thèse, nous nous intéressons en particulier à l'apprentissage dans un contexte multimodal, c'est à dire à la formation de représentations cohérentes à partir de plusieurs modalités sensorielles et/ou motrices. Notre modèle s'inspire du cortex cérébral, lieu supposé de la fusion multimodale dans le cerveau, et le représente à une échelle mésoscopique par des colonnes corticales regroupées en cartes et des projections axoniques entre ces cartes. Pour effectuer nos simulations, nous proposons une bibliothèque simplifiant la construction et l'évaluation de modèles mésoscopiques. Notre modèle d'apprentissage se base sur le modèle BCM (Bienenstock-Cooper-Munro), qui propose un algorithme d'apprentissage non-supervisé local (une unité apprend à partir de ses entrées de manière autonome) et biologiquement plausible. Nous adaptons BCM en introduisant la notion d'apprentissage guidé, un moyen de biaiser la convergence de l'apprentissage BCM en faveur d'un stimulus choisi. Puis, nous mettons ce mécanisme à profit pour effectuer un co-apprentissage entre plusieurs modalités. Grâce au co-apprentissage, les sélectivités développées sur chaque modalité tendent à représenter le même phénomène, perçu à travers différentes modalités, élaborant ainsi une représentation multimodale cohérente dudit phénomène.
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Ta, Thanh Dinh. "Modèle de protection contre les codes malveillants dans un environnement distribué". Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0040/document.
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La thèse contient deux parties principales: la première partie est consacrée à l’extraction du format des messages, la deuxième partie est consacrée à l’obfuscation des comportements des malwares et la détection. Pour la première partie, nous considérons deux problèmes: "la couverture des codes" et "l’extraction du format des messages". Pour la couverture des codes, nous proposons une nouvelle méthode basée sur le "tainting intelligent" et sur l’exécution inversée. Pour l’extraction du format des messages, nous proposons une nouvelle méthode basée sur la classification de messages en utilisant des traces d’exécution. Pour la deuxième partie, les comportements des codes malveillants sont formalisés par un modèle abstrait pour la communication entre le programme et le système d’exploitation. Dans ce modèle, les comportements du programme sont des appels systèmes. Étant donné les comportements d’un programme bénin, nous montrons de façon constructive qu’il existe plusieurs programmes malveillants ayant également ces comportements. En conséquence, aucun détecteur comportemental n’est capable de détecter ces programmes malveillantsThe thesis consists in two principal parts: the first one discusses the message for- mat extraction and the second one discusses the behavioral obfuscation of malwares and the detection. In the first part, we study the problem of “binary code coverage” and “input message format extraction”. For the first problem, we propose a new technique based on “smart” dynamic tainting analysis and reverse execution. For the second one, we propose a new method using an idea of classifying input message values by the corresponding execution traces received by executing the program with these input values. In the second part, we propose an abstract model for system calls interactions between malwares and the operating system at a host. We show that, in many cases, the behaviors of a malicious program can imitate ones of a benign program, and in these cases a behavioral detector cannot distinguish between the two programs
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Hinge, Antoine. "Dessin de graphe distribué par modèle de force : application au Big Data". Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0092/document.
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Les graphes, outil mathématique pour modéliser les relations entre des entités, sont en augmentation constante du fait d'internet (par exemple les réseaux sociaux). La visualisation de graphe (aussi appelée dessin) permet d'obtenir immédiatement des informations sur le graphe. Les graphes issus d'internet sont généralement stockés de manière morcelée sur plusieurs machines connectées par un réseau. Cette thèse a pour but de développer des algorithmes de dessin de très grand graphes dans le paradigme MapReduce, utilisé pour le calcul sur cluster. Parmi les algorithmes de dessin, les algorithmes reposants sur un modèle physique sous-jacent pour réaliser le dessin permettent d'obtenir un bon dessin indépendamment de la nature du graphe. Nous proposons deux algorithmes par modèle de forces conçus dans le paradigme MapReduce. GDAD, le premier algorithme par modèle de force dans le paradigme MapReduce, utilise des pivots pour simplifier le calcul des interactions entre les nœuds du graphes. MuGDAD, le prolongement de GDAD, utilise une simplification récursive du graphe pour effectuer le dessin, toujours à l'aide de pivots. Nous comparons ces deux algorithmes avec les algorithmes de l'état de l'art pour évaluer leurs performancesGraphs, usually used to model relations between entities, are continually growing mainly because of the internet (social networks for example). Graph visualization (also called drawing) is a fast way of collecting data about a graph. Internet graphs are often stored in a distributed manner, split between several machines interconnected. This thesis aims to develop drawing algorithms to draw very large graphs using the MapReduce paradigm, used for cluster computing. Among graph drawing algorithms, those which rely on a physical model to compute the node placement are generally considered to draw graphs well regardless of the type of graph. We developped two force-directed graph drawing algorithms in the MapReduce paradigm. GDAD, the fist distributed force-directed graph drawing algorithm ever, uses pivots to simplify computations of node interactions. MuGDAD, following GDAD, uses a recursive simplification to draw the original graph, keeping the pivots. We compare these two algorithms with the state of the art to assess their performances
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Debrie, Jean-Luc. "Modèle "distribué" de transistor IGBT pour simulation de circuits en électronique de puissance". Toulouse, INSA, 1996. http://www.theses.fr/1996ISAT0046.
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L'equation de diffusion ambipolaire, qui decrit la dynamique distribuee des charges dans les bases des composants bipolaires, peut etre resolue par le biais d'une analogie electrique. La these presente les fondements theoriques et la pratique de la nouvelle approche de modelisation ainsi permise, dans le cas representatif des transistors bipolaires a commande isolee (igbt). Les divers types d'igbt, a base homogene ou a couche tampon, sont pris en consideration. Le modele est valide d'un point de vue physique, les parametres de simulation etant extraits des donnees de structure et de technologie concernant les composants etudies. L'accord obtenu entre caracteristiques calculees et mesurees montre la pertinence de l'approche pour des objectifs de simulation des interactions composant-circuit en electronique de puissance.
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Nguyen, Quoc Son. "Application du modèle distribué événementiel SCS-LR pour la prévision des crues méditerranéennes : performances du modèle et variabilité spatiale des paramètres". Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTG019/document.
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Les modèles pluie-débit sont des outils essentiels pour de nombreuses applications hydrologiques, notamment la prévision des crues. L’objet de cette thèse est d’examiner les performances d’un modèle événementiel distribué, dont l’intérêt est de résumer la représentation des processus à la phase de crue, et la condition initiale à un indice de saturation du bassin facilement observable ou accessible. Ce dernier dispense de modéliser la phase inter-crue, et simplifie la paramétrisation et le calage du modèle. Le modèle étudié combine une fonction de production type SCS et une fonction de transfert type lag and route, appliquées à une discrétisation du bassin en mailles carrées régulières.Le modèle est d’abord testé sur le bassin versant du Real Collobrier. Ce bassin méditerranéen est suivi depuis plus de 50 ans par l’IRSTEA, et dispose d’une exceptionnelle densité de mesures de pluies et de débits. Cet environnement favorable permet de limiter les incertitudes sur l’estimation des pluies et d’évaluer les performances intrinsèques du modèle. Dans ces conditions, les crues sont bien reconstituées à l’aide d’un jeu de paramètres unique pour l’ensemble des épisodes testés, à l’exception de la condition initiale du modèle. Celle-ci apparaît fortement corrélée avec l’humidité du sol en début d’épisode, et peut être prédéterminée de façon satisfaisante par le débit de base ou l’indice w2 fourni par le modèle SIM de Météo-France. Les performances du modèle sont ensuite étudiées en dégradant la densité des pluviomètres, et rendent compte du niveau de performances du modèle dans les cas que l’on rencontre le plus souvent. .La variabilité spatiale des paramètres du modèle est étudiée à l’échelle de différents sous-bassins du Real Collobrier. La comparaison a permis de mettre en évidence et de corriger un effet d’échelle concernant l’un des paramètres de la fonction de transfert. Les relations entre la condition initiale du modèle et les indicateurs d’humidités des sols en début d’épisode restent bonnes à l’échelle des sous-bassins, mais peuvent être significativement différentes selon les sous-bassins. Une seule relation ne permet pas de normaliser l’initialisation du modèle sur l’ensemble des sous-bassins, à une échelle spatiale de quelques km2 ou dizaines de km2. Dans le cas de l’indice d’humidité du sol w2, une explication possible est que cet indice ne prend pas en compte suffisamment finement les propriétés des sols. Enfin, la variabilité spatiale des paramètres du modèle est étudiée à l’échelle d’un échantillon d’une quinzaine de bassins méditerranéens de quelques centaines de km2, associés à des paysages et des fonctionnements hydrologiques divers. La comparaison montre qu’à cette échelle, le lien entre les indicateurs de saturation du bassin et la condition initiale peut rester stable par type de bassin, mais varie significativement d’un type de bassin à l’autre. Des pistes sont proposées pour expliquer cette variation.En conclusion, ce modèle événementiel distribué représente un excellent compromis entre performances et facilité de mise en œuvre. Les performances sont satisfaisantes pour un bassin donné ou pour un type de bassin donné. L’analyse et l’interprétation de la variabilité spatiale des paramètres du modèle apparaît cependant complexe, et doit faire l’objet du test d’autres indicateurs de saturation des bassins, par exemple mesures in situ ou mesures satellitaires de l’humidité des solsRainfall-runoff models are essential tools for many hydrological applications, including flood forecasting. The purpose of this thesis was to examine the performances of a distributed event model for reproducing the Mediterranean floods. This model reduces the parametrization of the processes to the flood period, and estimates the saturation of the catchment at the beginning of the event with an external predictor, which is easily observable or available. Such predictor avoids modelling the inter-flood phase and simplifies the parametrization and the calibration of the model. The selected model combines a distributed SCS production function and a Lag and Route transfer function, applied to a discretization of the basin in a grid of regular square meshes.The model was first tested on the Real Collobrier watershed. This Mediterranean basin has been monitored by IRSTEA for more than 50 years and has an exceptional density of rainfall and flow measurements. This favourable environment made it possible to reduce the uncertainties on the rainfall input and to evaluate the actual performances of the model. In such conditions, the floods were correctly simulated by using constant parameters for all the events, but the initial condition of the event-based model. This latter was highly correlated to predictors such as the base flow or the soil water content w2 simulated by the SIM model of Meteo-France. The model was then applied by reducing the density of the rain gauges, showing loss of accuracy of the model and biases in the model parameters for lower densities, which are representative of most of the catchments.The spatial variability of the model parameters was then studied in different Real Collobrier sub-basins. The comparison made it possible to highlight and correct the scale effect concerning one of the parameters of the transfer function. The catchment saturation predictors and the initial condition of the model were still highly correlated, but the relationships differed from some sub-catchments. Finally, the spatial variability of the model parameters was studied for other larger Mediterranean catchments, of which area ranged from some tenth to hundreds of square kilometres. Once more, the model could be efficiently initialized by the base flow and the water content w2, but significant differences were found from a catchment to another. Such differences could be explained by uncertainties affecting as well the rainfall estimation as the selected predictors. However, the relationships between the initial condition of the model and the water content w2 were close together for a given type of catchment.In conclusion, this distributed event model represents an excellent compromise between performance and ease of implementation. The performances are satisfactory for a given catchment or a given type of catchment. The transposition of the model to ungauged catchment is less satisfactory, and other catchment saturation indicators need to be tested, e.g. in situ measurements or satellite measurements of soil moisture
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El, Houri Marwa. "Un modèle formel pour exprimer des politiques dynamiques pour contrôle d'accès et négociation dans un environnement distribué". Phd thesis, Université Paul Sabatier - Toulouse III, 2010. http://tel.archives-ouvertes.fr/tel-00492317.
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L'objectif principal de cette thèse est de définir un langage logique de haut niveau qui permet l'expression de politiques de sécurité complexes au sein d'un modèle de contrôle d'accès. Le développement de ce langage se fait en trois temps. Dans un premier temps nous présentons un modèle dynamique basé sur les rôles. Ainsi, nous considérons que l'évolution de l'état de sécurité d'un service dépend de l'exécution de ses fonctionnalités. Dans un deuxième temps nous définissons un formalisme basé sur les attributs qui offre plus de flexibilité en termes de spécifications des conditions de contrôle d'accès, et ajoutons la notion de workflow qui permet de modéliser le comportement d'un service. Dans un dernier temps, nous ajoutons un mécanisme de négociation qui permet à chaque service de définir sa propre politique d'échange avec les autres services dans l'environnement. La conception d'un tel cadre logique unifié facilite l'analyse de sûreté des politiques de sécurité puisque tous les facteurs qui influencent les décisions de contrôle d'accès sont pris en compte dans le même cadre. Ainsi le second objectif de cette thèse est d'étudier d'une part les principales propriétés de contrôle d'accès tels la délégation et la séparation des tâches et d'autre part les propriétés de sécurité pour la communication entre les différents services au niveau de la négociation.
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Gillet, Pierre. "Modèle "distribué" de transistor bipolaire pour la C. A. O. Des circuits en électronique de puissance". Toulouse, INPT, 1995. http://www.theses.fr/1995INPT003H.
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Ce memoire est consacre a la prise en compte de la nature distribuee de la dynamique des charges, dans la modelisation du transistor bipolaire de puissance destine a la conception assistee par ordinateur des circuits. Pour cela, nous proposons une methode de resolution analogique de l'equation de diffusion ambipolaire dans la zone de stockage de charge, basee sur une representation spectrale de la repartition des porteurs. Cette methode nous conduit a traiter un systeme de n equations differentielles du premier ordre, qui peut etre traduit sous forme de circuit electrique equivalent du type ligne rc serie. Ces lignes rc, a parametres variables dans le temps, representent le noyau de calcul du modele a partir duquel nous deduisons les grandeurs physiques internes responsables du comportement externe du dispositif. Ce noyau est complete par la representation des regions de base physique et d'emetteur traitees de maniere localisee, ainsi que l'influence du courant de deplacement, de la charge des porteurs en transit et du profil de dopage. Enfin, une comparaison simulation experience dans un environnement circuit simple mais realiste, mettant en evidence les interactions composant-circuit, montre le bien fonde de cette approche
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Siala, Beji Mariem. "Un modèle distribué pour la gestion du stock disponible dans les réseaux de distribution multi-niveaux". Lyon, INSA, 2008. http://www.theses.fr/2008ISAL0031.
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La fonction Available-To-Promise (ATP) se situe au cœur de la relation entre une compagnie et ses clients ou prospects. Le rôle de cette fonction est de fournir, en réponse à des requêtes clients, des informations sur la disponibilité des produits. Le but de cette thèse est d’améliorer cette fonction ATP, dans le cadre d’un réseau de distribution multi-niveaux. Le modèle proposé est un modèle distribué basé sur les horizons. Pour l’horizon court terme, nous proposons la fonction ATP Effectif (ATPE). Cette fonction assure une meilleure gestion du stock local au sein des différentes entités du réseau de distribution. Pour l’horizon moyen terme, nous proposons la fonction ATPE Coopératif (ATPE-C) qui se base sur une approche multi-agent, utilisant le protocole « Contract Net », pour assurer le redéploiement des stocks entre les différentes entités du réseaux de distribution. Pour évaluer ces fonctions, nous avons développé un outil de simulation qui a servi non seulement à montrer l’efficacité des fonctions proposées mais aussi à étudier l’influence du degré de coopération du système et des agents sur les performances globales et individuellesThe Available-to-Promise (ATP) fonction is an important element to manage the relationship between a company and its current and prospective customers. The initial role of this fonction is to provide product availability information in order to promise customers' order requests. The purpose of the present thesis is to improve this A TP fonction, within a multi-echelon distribution network. The suggested model is a distributed mode! based on horizons. For the short-term horizon, we suggest the Effective A TP fonction (ATPE). This fonction provides a better local stock management within the different entities of the distribution network. For the medium-term horizon, we suggest the Cooperative ATPE fonction (ATPE-C) which is based on a multi-agent approach, using the "Contract Net" protocoJ to assure the inventory redeployment between the different entities of the distribution network. In order to assess these fonctions we have developed a simulation tool which allowed us to show the e:fficiency of the suggested functi. Ons as weil as to study the impact of the system and the agents' cooperation degree on the global and individual performances
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Tran-The, Hung. "Problème du Consensus dans le Modèle Homonyme". Phd thesis, Université Paris-Diderot - Paris VII, 2013. http://tel.archives-ouvertes.fr/tel-00925941.
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So far, the distributed computing community has either assumed that all the processes of a distributed system have distinct identifiers or, more rarely, that the processes are anonymous and have no identifiers. These are two extremes of the same general model: namely, n processes use l different identifiers, where 1 l n. We call this model homonymous model. To determine the power of homonymous model as well as the importance of identifiers in distributed computing, this thesis studies the consensus problem, one of the most famous distributed computing problem. We give necessary and sufficient conditions on the number of identifiers for solving consensus in a distributed system with t faulty processes in the synchronous case. We show that in crash, send omission and general omission failures model, the uniform consensus is solvable even if processes are anonymous. Thus, identifiers are not useful in that case. However identifiers become important in Byzantine failures model: 3t + 1 identifiers is necessary and sufficient for Byzantine agreement. Surprisingly the number of identifiers must be greater than n+3t 2 in presence of three facets of uncertainty: partial synchrony, Byzantine failures and homonyms. This demonstrates two differences from the classical model (which has l = n): there are situations where relaxing synchrony to partial synchrony renders agreement impossible, and, in the partially synchronous case, increasing the number of correct processes can actually make it harder to reach agreement.
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Xu, Jin. "Un modèle multi-agent distribué et hybride pour la planification du transport à la demande temps réel". Phd thesis, INSA de Rouen, 2008. http://tel.archives-ouvertes.fr/tel-00558769.
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Durant ces dernières années, la congestion du trafic urbain et la pollution de l'air sont devenus d'énormes problèmes dans de nombreuses villes dans le monde. Afin de réduire cette congestion, nous pouvons investir dans l'amélioration des infrastructures de la ville. Toutefois, cette solution reste très coûteuse à entreprendre et de ne permet pas de réduire la pollution de l'air. C'est pourquoi nous travaillons sur la mobilité intelligente afin de disposer d'une meilleure utilisation de la voiture. L'application de nouvelles technologies de l'information, tels que les systèmes multi-agents appliqués au contrôle de l'information de la circulation urbaine, a permis de créer et de déployer une gestion plus intelligente du trafic comme le système DRT (transport à la demande). L'objectif des systèmes multi-agents basés sur le DRT est de gérer les taxis de manière intelligente, afin d'accroître le nombre de passagers dans chaque véhicule, et en même temps à réduire le nombre de véhicules dans les rues. Cela permettra de réduire les émissions de CO2 et la pollution de l'air causée par les véhicules, ainsi que la congestion du trafic et les coûts financiers associés. La simulation multi-agents est considérée comme un outil efficace pour les services dynamiques urbains de la circulation. Toutefois, le principal problème est de savoir comment construire un agent à base de modèle pour cette problématique. Ces travaux de recherche présente une solution basée sur les systèmes multi-agents réactifs pour la problématique du transport à la demande (DRT), qui adopte une approche multi-agent de planification urbaine en utilisant des services de contrôle qui satisfont aux principales contraintes : réduction de la période totale creuse, demandes spéciales du client, augmentation du nombre de places utilisées dans un même taxi, utilisation du nombre minimal de véhicules, etc. Dans cette thèse, nous proposons un modèle multi-agents multicouche hybride distribué pour des problématiques en temps réel. Dans la méthode proposée, un agent pour chaque véhicule trouve un ensemble de routes pour sa recherche locale, et choisit un itinéraire en coopérant avec d'autres agents se trouvant dans son domaine de planification. Nous avons examiné expérimentalement, l'efficacité de la méthode proposée.
Libros sobre el tema "Modèle distribué"
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Cevelev, Aleksandr. Material management of railway transport. ru: INFRA-M Academic Publishing LLC., 2020. http://dx.doi.org/10.12737/1064961.
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In the monograph reviewed the development of the inventory management of railway transport in the new economic environment of market economy.
According to the results of theoretical research, innovative and production potential of the supply system of railway transport the main directions and methods of transformation of the restructuring process under the corporate changes of JSC "RZD", positioned value system of the logistics of railway transportation, and developed a classification model used logistical resources.
Evaluation of activity of structural divisions of Russian Railways supply is proposed to be viewed through an integrated and comprehensive approach to the development of systems of balanced indicators of supply and prompt handling of material resources, the implementation of which allows to distribute the strategic objectives of the company "Russian Railways" activities in the system of logistics of the Railways and also to involve in economic circulation of excessive and unused inventories of material and technical resources and efficiently reallocate them among enterprises at the site of the railway.
Recommendations for the implementation of the developed algorithms and models are long term in nature and are based on the concept of logistics management and improve the business processes of the logistics system.
Will be useful for managers and specialists of directorates of logistics of Russian Railways supply, undergraduates and graduate students interested in the economy of railway transport.
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Theories of distributive justice. Cambridge, Mass: Harvard University Press, 1996.
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Gardarin, G. Relational databases and knowledge bases. Reading, Mass: Addison-Wesley, 1989.
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E, Rumelhart David, ed. Explorations in parallel distributed processing: A handbook of models, programs, and exercises. Cambridge, Mass: MIT Press, 1988.
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E, Rumelhart David, ed. Explorations in parallel distributed processing: A handbook of models, programs, and exercises. Cambridge, Mass: MIT Press, 1990.
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McClelland, James L. Explorations in parallel distributed processing: A handbook of models, programs, and exercises. Cambridge, Mass: MIT Press, 1989.
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Winkler, Emily A. The Foundations of Conditional Kingship. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780198812388.003.0002.
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In Old Testament narratives, invasion and conquest were the catalysts of the institution of kingship. Chapter 2 explores relevant biblical models for medieval kingship, both conditional and unconditional. It also considers the paradoxes of writers’ decisions about how to distribute responsibility and justice in classical sources, which lacked a providential framework for the explanation of human actions and obligations. Together, these ancient models of royal responsibility, both causal and moral, illuminate approaches to the problem of explaining contingency with which later writers were familiar. The chapter also identifies several key Carolingian precedents for guiding evaluating kings to show where Anglo-Saxon and Anglo-Norman thought about kingship diverged from continental models.
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Rogerson, Kenneth. International Communication in Social Movements and Interest Groups. Oxford University Press, 2017. http://dx.doi.org/10.1093/acrefore/9780190846626.013.226.
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Ideas and people may be mobilized in order to influence the thinking of policy makers or society to either promote a specific point of view or enact policy in the form of laws or programs that benefit the ideas or people. This mobilization of ideas and people is known as political advocacy, which falls into two broad categories: social action and social mobilization, which can—but not necessarily—give rise to social movements, and interest and lobbying groups. According to Mancur Olson, groups are organized to pursue a common good or benefit. The success or failure of such groups can be explained using models such as the classical model, the resource mobilization model, and the “political process” model. The success of political advocacy is contingent upon a number of interrelated concepts and characteristics, including access to resources (money, people, and time), good leadership, a sense of identity or common focus, and the opportunity to be heard. A movement can distribute its message to its target audience—for example, policy makers, opinion leaders, potential participants, or the public at large—by means of information and communications technologies (ICTs). Two theses are used to assess the effectiveness of ICTs in political advocacy: the mobilization thesis and the reinforcement thesis. The inclusion of international communication has enriched our understanding of how, when, where, and why political advocacy is or is not effective.
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Grover, Robert J., Kelly Visnak, Carmaine Ternes, Miranda Ericsson y Lissa Staley. Libraries Partnering with Self-Publishing. ABC-CLIO,LLC, 2016. http://dx.doi.org/10.5040/9798400678905.
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Help your library leverage opportunities in the popular do-it-yourself publishing movement by following this guide's process for creating and producing books. In this useful guidebook, you'll learn how to transform your library into a self-publishing center with pointers, advice, and strategies for creating, producing, and printing books both digitally and on paper. The book outlines your partnering role with patrons in the creation of published materials, offering step-by-step guidance for assisting library users who wish to put their written words in print. By using the detailed plan in this reference, you'll be able to help patrons identify an audience for their material, select the best publishing software for their needs, and utilize social media to promote and distribute their work. Chapters follow the publishing process from planning to creative development, production, and marketing. The final chapter features books, websites, and Internet sources for designing brochures; creating a website; and designing, printing, and distributing a book. Helpful guidelines accompany excerpts from interviews with librarians experienced with this publishing model, examples of self-published books, and graphic models.
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Narr, Wayne, David S. Schechter y Laird B. Thompson. Naturally Fractured Reservoir Characterization. Society of Petroleum Engineers, 2006. http://dx.doi.org/10.2118/9781613999615.
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Naturally fractured reservoirs present unique and specialized challenges to hydrocarbon extraction. Naturally Fractured Reservoir Characterization seeks to confront many of these challenges by providing an introduction to the engineering and geological character of naturally fractured reservoirs. The focus is on understanding fractures in a reservoir – how to determine whether fractures are important to hydrocarbon producibility, and if so, how to analyze the fracture system for the purpose of improved reservoir management. Topics discussed include the geological character of fracture systems, how to recognize and describe them, their effect on reservoir performance, how to distribute them in a reservoir model, and different approaches to flow simulation. A blend of engineering and geological data and tools are used to optimize our understanding of this class of reservoirs. Case histories of several naturally fractured reservoirs are presented to show that a range of strategies may be required to successfully address the complexity of this diverse class of reservoirs.
Capítulos de libros sobre el tema "Modèle distribué"
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Santhanavanich, Thunyathep, Rosanny Sihombing, Pithon Macharia Kabiro, Patrick Würstle y Sabo Kwado Sini. "Storing and Visualising Dynamic Data in the Context of Energy Analysis in the Smart Cities". En iCity. Transformative Research for the Livable, Intelligent, and Sustainable City, 251–65. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92096-8_16.
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AbstractThere is increased activity in developing workflows and implementations in the context of urban energy analysis simulation based on 3D city models in smart cities. At the University of Applied Sciences Stuttgart (HFT Stuttgart), an urban energy simulation platform called ‘SimStadt’ has successfully been developed. It uses the CityGML 3D city model to simulate the heat demand, photovoltaic potential, and other scenarios that provide dynamic simulation results in both space and time dimensions. Accordingly, a tool for managing dynamic data of the CityGML models is required. Earlier, the CityGML Application Domain Extension (ADE) had been proposed to support additional attributes of the CityGML model; however, there is still a lack of open-source tools and platforms to manage and distribute the CityGML ADE data efficiently. This article evaluates and compares alternative methods to manage dynamic simulation results of the 3D city model and visualise these data on the 3D web-based smart city application, including the use of SimStadt web services, databases, and OGC SensorThings API standard.
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Disabato, Simone. "Deep and Wide Tiny Machine Learning". En Special Topics in Information Technology, 79–92. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-15374-7_7.
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AbstractIn the last decades, on the one hand, Deep Learning (DL) has become state of the art in several domains, e.g., image classification, object detection, and natural language processing. On the other hand, pervasive technologies—Internet of Things (IoT) units, embedded systems, and Micro-Controller Units (MCUs)—ask for intelligent processing mechanisms as close as possible to data generation. Nevertheless, memory, computational, and energy requirements characterizing DL models are three or more orders of magnitude larger than the corresponding memory, computation, and energy capabilities of pervasive devices. This work aims at introducing a methodology to address this issue and enable pervasive intelligent processing. In particular, by defining Tiny Machine Learning (TML) solutions, i.e., machine and deep learning models that take into account the constraints on memory, computation, and energy of the target pervasive device. The proposed methodology addresses the problem at three different levels. In the first approach, the methodology devices inference-based Deep TML solutions by approximation techniques, i.e., the TML model runs on the pervasive device but was trained elsewhere. Then, the methodology introduces on-device learning for TML. Finally, the third approach develops Wide Deep TML solutions that split and distribute the DL processing over connected heterogeneous pervasive devices.
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Chung, Minh Thanh, Josef Weidendorfer, Karl Fürlinger y Dieter Kranzlmüller. "Proactive Task Offloading for Load Balancing in Iterative Applications". En Parallel Processing and Applied Mathematics, 263–75. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-30442-2_20.
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AbstractLoad imbalance is often a challenge for applications in parallel systems. Static cost models and pre-partitioning algorithms distribute the load at the beginning. Nevertheless, dynamic changes during execution or inaccurate cost indicators may lead to imbalance at runtime. Reactive work-stealing strategies can help monitor the execution and perform task migration to balance the load. However, the benefits depend on migration overhead and assumption about future execution.Our proactive approach further improves existing solutions by applying machine learning to online load prediction. Following that, we propose a fully distributed algorithm for adapting the prediction result to guide task offloading. The experiments are performed with an artificial test case and a realistic application named Sam(oa)$$^2$$ 2 on three systems with different communication overhead. Our results confirm improvements for important use cases compared to previous solutions. Furthermore, this approach can support co-scheduling tasks across multiple applications.
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Putkonen, Aini, Aurélien Nioche, Markku Laine, Crista Kuuramo y Antti Oulasvirta. "Fragmented Visual Attention in Web Browsing: Weibull Analysis of Item Visit Times". En Lecture Notes in Computer Science, 62–78. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-28238-6_5.
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AbstractUsers often browse the web in an exploratory way, inspecting what they find interesting without a specific goal. However, the temporal dynamics of visual attention during such sessions, emerging when users gaze from one item to another, are not well understood. In this paper, we examine how people distribute visual attention among content items when browsing news. Distribution of visual attention is studied in a controlled experiment, wherein eye-tracking data and web logs are collected for 18 participants exploring newsfeeds in a single- and multi-column layout. Behavior is modeled using Weibull analysis of item (article) visit times, which describes these visits via quantities like durations and frequencies of switching focused item. Bayesian inference is used to quantify uncertainty. The results suggest that visual attention in browsing is fragmented, and affected by the number, properties and composition of the items visible on the viewport. We connect these findings to previous work explaining information-seeking behavior through cost-benefit judgments.
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Savary, C., B. Bertin, M. Lenaerts, I. El Ouamari y D. Bousmar. "Transverse Mooring Forces Due to Asymmetrical Filling in a Lock with Longitudinal Culverts and Side Ports". En Lecture Notes in Civil Engineering, 724–35. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-6138-0_63.
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AbstractIn lock design, several geometries are proposed for the levelling system with the aim of insuring a smooth and fast levelling operation. For high and medium lift lock, longitudinal culverts with side ports located in the lock walls are often chosen because this system distribute the flow along the entire length of the lock chamber. Nevertheless, when one of the culvert (valve) is out of order, the flow is asymmetrical what induced significant transverse mooring forces, especially during filling operations.Field measurement on such a lock (225 m long, 25 m wide and 13.5 m lift) demonstrated transverse water slopes significantly larger than the admissible criteria during asymmetrical filling operation. Further investigations on a physical scale model highlighted the driving effect of the side port jets on the rolling flow. Detailed measurements were performed on the scale model covering: (1) water surface slope; (2) transverse velocity distribution; (3) transverse mooring forces and rolling angle of a vessel located in the lock chamber. It was concluded that the size of the outlets of the side ports has a major impact on the transverse forces. For smaller outlets at a given discharge, the flow velocity increases and more impulse is transferred to the rolling flow, resulting in larger forces on the vessel.
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Iriawan, Muhammad Ari. "Competence of Indonesian Social Security Driver (Shield) in Increasing Participation at BPJS Employment Medan City Branch". En Proceedings of the 19th International Symposium on Management (INSYMA 2022), 561–65. Dordrecht: Atlantis Press International BV, 2022. http://dx.doi.org/10.2991/978-94-6463-008-4_71.
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AbstractSocial security is an essential thing needed by everyone, including employment social security for Indonesian workers. The Penggerak Jaminan Sosial Indonesia (PERISAI), an agent in social security, plays an essential role in conveying the benefits of the existing social security program to protect workers. PERISAI’s competencies play a vital role in achieving maximum results in delivering information and participant acquisition. One appropriate method consistent in determining PERISAI’s competencies is the Analytical Hierarchy Process method. The Analytic Hierarchy Process (AHP) is a compelling and comprehensive methodology that enables groups and individuals to link qualitative factors in the decision-making process. AHP uses a hierarchical model consisting of objectives, criteria (and several sub-criteria), and alternatives for each decision. This method was used with field surveys and field data collection to distribute the questionnaires (for this method). PERISAI’s creativity is the most influential competency in increasing the participation of Social Health Insurance Administration Body (BPJS) Employment in the Medan City Branch. In other words, in conducting recruitment for PERISAI, it is necessary to pay attention to creative competence.
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Álvarez Casado, Constantino, Pauli Räsänen, Le Ngu Nguyen, Arttu Lämsä, Johannes Peltola y Miguel Bordallo López. "A Distributed Framework for Remote Multimodal Biosignal Acquisition and Analysis". En Communications in Computer and Information Science, 127–46. Cham: Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-59091-7_9.
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AbstractIn recent times, several studies have presented single-modality systems for non-contact biosignal monitoring. While these systems often yield estimations correlating with clinical-grade devices, their practicality is limited due to constraints in real-time processing, scalability, and interoperability. Moreover, these studies have seldom explored the combined use of multiple modalities or the integration of various sensors. Addressing these gaps, we introduce a distributed computing architecture designed to remotely acquire biosignals from both radars and cameras. This architecture is supported by conceptual blocks that distribute tasks across sensing, computing, data management, analysis, communication, and visualization. Emphasizing interoperability, our system leverages RESTful APIs, efficient video streaming, and standardized health-data protocols. Our framework facilitates the integration of additional sensors and improves signal analysis efficiency. While the architecture is conceptual, its feasibility has been evaluated through simulations targeting specific challenges in networked remote photoplethysmography (rPPG) systems. Additionally, we implemented a prototype to demonstrate the architectural principles in action, with modules and blocks operating in independent threads. This prototype specifically involves the analysis of biosignals using mmWave radars and RGB cameras, illustrating the potential for the architecture to be adapted into a fully distributed system for real-time biosignal processing.
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Parung, Joniarto, Amelia Santoso, Dina Natalia Prayogo, Felita Griselda y Adi Tedjakusuma. "Multi-objective Location-Transportation Problem for Relief Distribution". En Proceedings of the 19th International Symposium on Management (INSYMA 2022), 1193–201. Dordrecht: Atlantis Press International BV, 2022. http://dx.doi.org/10.2991/978-94-6463-008-4_147.
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AbstractThe problem that is often encountered in every natural disaster is material damage and even loss of life; thus, systematic steps to reduce or prevent the impact of disasters are needed. A quick response is the main thing to carry out disaster management when a disaster occurs. The steps taken are mobilizing and deploying emergency services to protect people and reduce material damage within the affected areas. The primary response to minimize the impact is to distribute humanitarian aid. The distribution of aid includes 2 aspects: the speed of delivery of aid and the fulfillment of all the needs of disaster victims. This aspect is related to predicting the amount and time of distribution of necessities to be adequately distributed. Prediction of demand and distribution is influenced by many factors, including distance, availability of vehicles, number of affected people, operational time of aid providers, local conditions such as roads, needs of population groups, etc. This study aims to modify the existing mathematical model for the Multi-Objective Location-Transportation Problem. This modification was carried out to determine the number and time of effective delivery of essential goods based on heterogeneous vehicle capacities. This model was then applied to a case study for the distribution of goods during a volcanic eruption using data from Mount Bromo, East Java, Indonesia. The model development and application results in the case study show information on the number and timing of effective delivery of essential humanitarian aid items based on the available vehicle capacity at the location according to the conditions of the disaster location.
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Frønes, Tove Stjern, Andreas Pettersen, Jelena Radišić y Nils Buchholtz. "Equity, Equality and Diversity in the Nordic Model of Education—Contributions from Large-Scale Studies". En Equity, Equality and Diversity in the Nordic Model of Education, 1–10. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-61648-9_1.
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AbstractIn education, the ‘Nordic model’ refers to the similarities and shared aims of the education systems developed in the five Nordic countries—Denmark, Finland, Iceland, Sweden and Norway—after World War II. Traditionally, there have always been many similarities and links between the Nordic countries through their historical connections and geographical proximity. The common experience of solidarity and political oppression during World War II also created the basis for a common political orientation in the postwar period, which was also reflected in the education systems during the development of the countries’ economies and their establishment of welfare states. At the same time, this very process has been strongly supported by social-democratic governance in these countries in the 1960s and 1970s (Blossing, Imsen, & Moos, 2014). The model is based on a concept ofEducation for All, where equity, equal opportunities and inclusion are consistently cited as the goal of schooling and orientation (Blossing et al., 2014; Telhaug, Mediås, & Aasen, 2006). This corresponds to the egalitarian idea of a classless society, which is characterised by individual democratic participation, solidarity and mutual respect and appreciation for all. This idea was manifested in, for example, major reallocations of economic resources through the tax systems and free schooling for all, which arose out of the principle that parents’ lack of economic resources should not prevent children from obtaining a good quality education. The equalisation of structural inequalities and creation of equity was—and still is—the task of the education system in the Nordic countries. Worldwide, especially within the Nordic countries, the view is being shared that the education system should be fair and provide access and opportunities for further education, regardless of where someone lives, the status of the parental home, where someone comes from, what ethnic background someone has, what age or gender someone is, what skills one has or whether someone has physical disabilities (Blossing et al., 2014; Quaiser-Pohl, 2013). Some special features of the Nordic system are therefore deeply embedded in the school culture in the countries, for example, through the fact that access to free and public local schools and adapted education is statutory, which is in contrast to many other countries, even other European ones (further developed and discussed in Chap.10.1007/978-3-030-61648-9_2). The Nordic model is widely considered a good example of educational systems that provide equal learning opportunities for all students. Achieving equity, here meaning the creation of fairness, is expressed concretely in political measures to distribute resources equally and strengthen the equality of marginalised groups by removing the barriers to seize educational opportunities, for example, when mixed-ability comprehensive schools are created or the educational system is made inclusive regarding students with special needs (UNESCO, 1994; Wiborg, 2009). Equality is roughly connoted with ‘sameness in treatment’ (Espinoza, 2007), while equity takes further in consideration also the question of how well the requirements of individual needs are met. Thus, the goal of equity is always linked to the concept of justice, provided that an equality of opportunities is created. If, however, one looks at individual educational policy decisions on the creation of educational justice in isolation, one must weigh which concept of equity or equality is present in each case. For example, it is not enough to formally grant equal rights in the education system to disadvantaged groups, but something must also be done actively to ensure that marginalised groups can use and realise this equality. The complexity of the terms becomes even greater when one considers that to achieve equality, measures can be taken that presuppose an unequal distribution of resources or unequal treatment and, therefore, are not fair e.g., when resources are bundled especially for disadvantaged groups and these are given preferential treatment (will be further developed and discussed in Chap.10.1007/978-3-030-61648-9_2). Thus, equality and equity rely on each other and are in a field of tension comprising multiple ideas (Espinoza, 2007).
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Urrea, Claudia, Kirky Delong, Joe Diaz, Eric Klopfer, Meredith Thompson, Aditi Wagh, Jenny Gardony, Emma Anderson y Rohan Kundargi. "MIT Full STEAM Ahead: Bringing Project-Based, Collaborative Learning to Remote Learning Environments". En Knowledge Studies in Higher Education, 299–319. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-82159-3_20.
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AbstractWith schools and educational centers around the country moving from in-person to emergency remote learning due to the COVID-19 pandemic, education faces an unprecedented crisis (Hodges et al., Educause Review 27, 2020). This case study presents the efforts and impact of Full STEAM Ahead (FSA) launched by the Massachusetts Institute of Technology (MIT) in response to the pandemic to support remote collaborative learning for K-12 learners, parents, and educators. We present two FSA initiatives: (1) weekly themed packages with developmentally appropriate activities for K-12 remote learning and (2) Full STEAM Ahead Into Summer (FSAIS), an online summer program for middle school Massachusetts students, specifically targeting students who are at risk for “COVID Slide.” (Institute-wide Task Force on the Future of MIT Education-Final Report: http://web.mit.edu/future-report/TaskForceFinal_July28.pdf?) Our operative theory of change is that we can improve K-12 remote collaborative learning experiences through developing and sharing a curriculum that exemplifies the minds-on and hands-on approach advocated by MIT, strategically leveraging existing structures and projects within MIT, and establishing partnerships with the local and international community. We gauge the effect of these efforts on contributing members of the MIT community and targeted learners by analyzing data gathered through participant surveys and artifacts such as the website, packages, modules, and student projects created during the summer programs. Our findings indicate that existing structures and resources – with community building – facilitated the achievement of our goal to develop and distribute problem-based learning activities and that interaction and community building were central in meeting those goals. This work contributes to the knowledge base regarding emergency online learning and the development of effective university outreach efforts.
Actas de conferencias sobre el tema "Modèle distribué"
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Zhao, Zhou, Gang Hu, Qijie Wang, Qixiang Cao, Kaiming Feng y Guoshu Zhang. "Preliminary Design for the Back Plate of Sub-Module of CN HCCB TBM". En 2013 21st International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icone21-15461.
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The latest design of CN HCCB TBM is 1×4 configuration, which is consisted of 4 sub-modules and a big back plate. For the sub-module, the back plate is the most key and complicated part that is a multi pipes and plates structure, the space between the plates are to form the functional cavities that are used to distribute and collect the coolant and purge gas, the cavities are connected by the pipes. The cavity 1 is used to distribute the coolant (from the big back plate) into the branch cooling channels of caps and rib, the cavity 2 is to collect the coolant from the branch channels of caps and rib and to distribute it into lots of branch channels of cooling plates, the cavity 3 is to mix and collect the coolant from the branch channels of cooling plates that will flow into the back plate of TBM finally. The preliminary analysis results show that, the mass flow rate is between 2.20×10−2 and 2.33×10−2 kg/s for the coolant flowing into branch channels of caps, and it is between 1.82×10−3 kg/s and 1.84×10−3kg/s for that of rib, which indicates the cavity 1 will lead a good uniformity of mass flow rate; although the mass flow rate is between in a large range from 5.29×10−4 kg/s to 9.19×10−4kg/s for that of cooling plates, the thermal hydraulic analysis of sub-module shows that the minimum value (5.29 × 10−4 kg/s) can also meet the temperature requirements of materials.
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Lerat, Jean-Sébastien y Sidi Ahmed Mahmoudi. "Architecture to Distribute Deep Learning Models on Containers and Virtual Machines for Industry 4.0*". En 2023 IEEE 6th International Conference on Cloud Computing and Artificial Intelligence: Technologies and Applications (CloudTech). IEEE, 2023. http://dx.doi.org/10.1109/cloudtech58737.2023.10366111.
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Pranoto, Yudi, Hyun-suk Yoon y Clark Cheng. "Modeling Empty Intermodal Flatcar Distribution in an U.S. Class I Railroad". En 2013 Joint Rail Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/jrc2013-2474.
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In this paper, we discuss an effort to develop optimization models to distribute intermodal flatcars in an U.S. Class I railroad. The models were developed as strategic and tactical tools. We discuss model complexity and results.
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Wang, Ning y Shiyou Yang. "An Improved PSO based Methodology to Extract Frequency-Dependent Stray Parameters of High Order Distribute Circuit Models". En 2022 IEEE 20th Biennial Conference on Electromagnetic Field Computation (CEFC). IEEE, 2022. http://dx.doi.org/10.1109/cefc55061.2022.9940723.
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Souza, Rick Lopes de, Martin Vigil y Ricardo Felipe Custódio. "Análise de Vulnerabilidade de Esquemas de Segredo Compartilhado Considerando um novo Modelo de Ameaça". En Simpósio Brasileiro de Segurança da Informação e de Sistemas Computacionais. Sociedade Brasileira de Computação - SBC, 2017. http://dx.doi.org/10.5753/sbseg.2017.19511.
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Esquemas de segredo compartilhado são primitivas criptográficas utilizadas para distribuir partes de um segredo entre um conjunto de participantes de tal forma que apenas um subconjunto autorizado consiga reconstruir o segredo. Tradicionalmente, grande parte dos esquemas de segredo compartilhado trabalham com apenas duas definições de entidades: Distribuidor e Participante. Para esses esquemas, diversos modelos de ameaça foram propostos considerando apenas essas duas entidades. Todavia, na literatura não está claro quem deveria exercer o papel de reconstruir o segredo e quem seria o detentor do segredo. Essas duas novas entidades modificam os modelos de ameaça existentes que consideram o Distribuidor a entidade responsável por inicializar o esquema, gerar parâmetros do sistema, gerar o segredo, criar as partes e distribuir, e Participantes que cooperam ou não com a reconstrução do segredo. Neste trabalho propomos um novo modelo de ameaça considerando as novas entidades que representam todos os papéis envolvidos em esquemas de segredo compartilhado. À luz desse novo modelo, alguns dos esquemas mais conhecidos mostram-se vulneráveis. Também são feitas avaliações verificando quais pontos consegue-se manter segurança e em quais pontos surgirão vulnerabilidades de acordo com as novas entidades e modelos de ameaça definidos.
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Sanches, Matheus Ferraroni, Jader M. C. de Sá, Henrique T. S. Foerste, Rafael R. Souza, Julio C. Dos Reis y Leandro A. Villas. "Textual Datasets For Portuguese-Brazilian Language Models". En Dataset Showcase Workshop. Sociedade Brasileira de Computação, 2022. http://dx.doi.org/10.5753/dsw.2022.224294.
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Advances in Natural Language Processing have generated new models that push forward the state of the art. This reached new heights in complex tasks in handling unstructured texts. Most of the new architectures and models focus on the English language. There is a lack of available datasets that can be used during the training of new models. This investigation presents four new textual datasets for language modeling in Brazilian Portuguese. Our datasets were generated from several specific methodologies that aimed to obtain data of different natures. Two of our sets were originally built from data in online web forums. We also distribute a translated version of MultiWOZ, and a clean version of BrWaC. The original datasets are made available in a structured way to facilitate their use during the training of NLP models, with questions, answers and conversations already identified.
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de Jesus, Genival Sena, Joa˜o Roberto Barbosa y Kenneth W. Ramsden. "A Comparison of Loss Models Using Different Radial Distribution of Loss in an Axial Turbine Streamline Curvature Program". En ASME Turbo Expo 2007: Power for Land, Sea, and Air. ASMEDC, 2007. http://dx.doi.org/10.1115/gt2007-27641.
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The streamline computer codes published in the open literature and used to analyze the performance of axial flow turbines have employed a particular loss model chosen from a number of existing prediction methods. It is well known that the performance prediction methods developed for one-dimensional models concentrates the losses at the blade mid-height. When used in a streamline curvature model, however it is necessary to distribute these losses along the blade span. However the way to distribute the losses is not unique, as is clear from the open literature. Some methods seem to be an arbitrary procedure, with a shortcoming in representing the real flow behavior within the blade row. In this paper, two different loss distribution models were implemented in a streamline curvature program specially developed for the study of axial flow turbine performance. The study seeks to establish which one best represents the reality of the complex flow physics occurring within a blade row. Three different loss models were also implemented in the program to check their reliability and validity when combined with different loss distribution systems. Performance maps for a single-stage turbine were generated by means of different combinations of loss models and radial loss distributions. The computed result for each case was compared with available experimental data of a single-stage turbine.
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Li, Min, Weimin Chen y Liwu Zhang. "A Finite Element Study of Multi-Mode VIV of Slender Riser Experiencing Non-Uniform Flow". En ASME 2011 30th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2011. http://dx.doi.org/10.1115/omae2011-49296.
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The dynamic characteristics of deepwater riser usually present serried modes with lower frequencies, because structural flexibility is very large due to high aspect ratio (ratio of length to diameter of riser). Moreover, in practice flow velocity usually distributes non-uniformly along the riser length. A coupling model, for multi-mode VIV (vortex-induced vibration) of slender riser experiencing non-uniform flow, by means of finite element simulation combined with the hydrodynamic model taking account of the interaction between fluid and structure in time-domain, is proposed. VIV responses of slender risers respectively in uniform, stepped and shear flow are explored. Satisfied agreements with experiment results are observed. Additionally, based on the numerical simulations effects of reduced velocity and modal energy on modal weight are explored. We note that for case of multi-mode vibration the participating modes tend to distribute by groups.
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Mohamed Elobaid Musa, Moneef, Xiong Xueyu, Landry Wilfried Tim Sob, Wael Alhaddad, Md Nasir Uddin y Faharidine Mahamoudou. "Finite Element Analysis of Local Pressure Failure Mechanism of RPC". En IABSE Congress, Nanjing 2022: Bridges and Structures: Connection, Integration and Harmonisation. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2022. http://dx.doi.org/10.2749/nanjing.2022.0686.
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<p>Reactive powder concrete (RPC) has been widely used due to its high tensile and compressive strength and excellent durability. However, the failure mechanism of RPC local pressure is still unclear. Therefore, reasonable structural dimensions of the finite element model (FEM) and the relevant parameters of the RPC were selected to deeply explore the local pressure of the RPC under the local loading. The FEM of the axial local compression of the RPC with different constitutive models was built. The whole nonlinear analysis process of the local pressure of RPC was completed, and the failure mode, stress distribution, and maximum plastic principal strain of the specimen were analyzed. The model shows that the local pressure performance of RPC is improved due to the increase of ultimate tensile strength, the local pressure failure mode of RPC conforms to the wedge split theory, and the orthogonal ties can uniformly distribute the pressure stresses.</p>
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Sasao, Yasuhiro, Shigeki Senoo, Ilias Bosdas y Anestis Kalfas. "Coarse Droplet Measurement at the Last Stage Stator Exit of a Four-Stage Scaled Steam Turbine Using an Optical Backscatter Probe". En ASME Turbo Expo 2023: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2023. http://dx.doi.org/10.1115/gt2023-103378.
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Abstract Size and velocity distributions in polydisperse coarse droplets are important to estimate and reduce erosion damage and wetness losses in wet steam turbines. Diameters and velocities of coarse droplets are measured by an optical backscatter probe downstream of the last stage stator in a four-stage model steam turbine at the rated condition. The droplet diameters distribute in the range from 30 to 90 micrometers. The Sauter mean droplet diameter is about 57 micrometers and the maximum droplet diameter is 88 micrometers. The corresponding Weber numbers are 11.4 and 17.6 respectively in the Sauter mean and maximum diameters. The Weber numbers are generally consistent with calculated values by both Kelvin-Helmholtz and Rayleigh-Taylor instability models. The mass flow rate and number of the coarse droplets is larger in the wake region from the stator, because the coarse droplets might be mainly generated by atomization of water films and rivulets on the stator. The larger droplets in diameter over 60 micrometers tend to axially deflect from steam flows. The Sauter mean diameters are slightly larger downstream from suction surface of the stator. The droplet velocities distribute in the range up to 40 m/s. The smaller droplets have the higher velocities as expected. Mean velocities are also consistent with predictions by the instability models. The measured number density distributions of coarse droplet diameters and velocities with the spatial resolution could improve the accuracy in models for blade erosion and wetness loss from models based on mean or maximum droplet diameter.
Informes sobre el tema "Modèle distribué"
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Urbina-Cardona, J. Nicolas, Rafael Loyola y undefined. Applying niche-based models to predict endangered-hylid potential distribut. The Nature Conservancy, diciembre de 2008. http://dx.doi.org/10.3411/col.12030215.
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He, Zhiguo, Sheila Jiang y Douglas Xu. Tech-Driven Intermediation in the Originate-to-Distribute Model. Cambridge, MA: National Bureau of Economic Research, enero de 2024. http://dx.doi.org/10.3386/w32052.
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Lazonick, William. Investing in Innovation: A Policy Framework for Attaining Sustainable Prosperity in the United States. Institute for New Economic Thinking Working Paper Series, marzo de 2022. http://dx.doi.org/10.36687/inetwp182.
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“Sustainable prosperity” denotes an economy that generates stable and equitable growth for a large and growing middle class. From the 1940s into the 1970s, the United States appeared to be on a trajectory of sustainable prosperity, especially for white-male members of the U.S. labor force. Since the 1980s, however, an increasing proportion of the U.S labor force has experienced unstable employment and inequitable income, while growing numbers of the business firms upon which they rely for employment have generated anemic productivity growth. Stable and equitable growth requires innovative enterprise. The essence of innovative enterprise is investment in productive capabilities that can generate higher-quality, lower-cost goods and services than those previously available. The innovative enterprise tends to be a business firm—a unit of strategic control that, by selling products, must make profits over time to survive. In a modern society, however, business firms are not alone in making investments in the productive capabilities required to generate innovative goods and services. Household units and government agencies also make investments in productive capabilities upon which business firms rely for their own investment activities. When they work in a harmonious fashion, these three types of organizations—household units, government agencies, and business firms—constitute “the investment triad.” The Biden administration’s Build Back Better agenda to restore sustainable prosperity in the United States focuses on investment in productive capabilities by two of the three types of organizations in the triad: government agencies, implementing the Infrastructure Investment and Jobs Act, and household units, implementing the yet-to-be-passed American Families Act. Absent, however, is a policy agenda to encourage and enable investment in innovation by business firms. This gaping lacuna is particularly problematic because many of the largest industrial corporations in the United States place a far higher priority on distributing the contents of the corporate treasury to shareholders in the form of cash dividends and stock buybacks for the sake of higher stock yields than on investing in the productive capabilities of their workforces for the sake of innovation. Based on analyzes of the “financialization” of major U.S. business corporations, I argue that, unless Build Back Better includes an effective policy agenda to encourage and enable corporate investment in innovation, the Biden administration’s program for attaining stable and equitable growth will fail. Drawing on the experience of the U.S. economy over the past seven decades, I summarize how the United States moved toward stable and equitable growth from the late 1940s through the 1970s under a “retain-and-reinvest” resource-allocation regime at major U.S. business firms. Companies retained a substantial portion of their profits to reinvest in productive capabilities, including those of career employees. In contrast, since the early 1980s, under a “downsize-and-distribute” corporate resource-allocation regime, unstable employment, inequitable income, and sagging productivity have characterized the U.S. economy. In transition from retain-and-reinvest to downsize-and-distribute, many of the largest, most powerful corporations have adopted a “dominate-and-distribute” resource-allocation regime: Based on the innovative capabilities that they have previously developed, these companies dominate market segments of their industries but prioritize shareholders in corporate resource allocation. The practice of open-market share repurchases—aka stock buybacks—at major U.S. business corporations has been central to the dominate-and-distribute and downsize-and-distribute regimes. Since the mid-1980s, stock buybacks have become the prime mode for the legalized looting of the business corporation. I call this looting process “predatory value extraction” and contend that it is the fundamental cause of the increasing concentration of income among the richest household units and the erosion of middle-class employment opportunities for most other Americans. I conclude the paper by outlining a policy framework that could stop the looting of the business corporation and put in place social institutions that support sustainable prosperity. The agenda includes a ban on stock buybacks done as open-market repurchases, radical changes in incentives for senior corporate executives, representation of workers and taxpayers as directors on corporate boards, reform of the tax system to reward innovation and penalize financialization, and, guided by the investment-triad framework, government programs to support “collective and cumulative careers” of members of the U.S. labor force. Sustained investment in human capabilities by the investment triad, including business firms, would make it possible for an ever-increasing portion of the U.S. labor force to engage in the productive careers that underpin upward socioeconomic mobility, which would be manifested by a growing, robust, and hopeful American middle class.
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Pelletier, Austin, Amanda Hohner, Idil Deniz Akin, Indranil Chowdhury, Richard Watts, Xianming Shi, Brendan Dutmer y James Mueller. Bench-scale Electrochemical Treatment of Co-contaminated Clayey Soil. Illinois Center for Transportation, junio de 2021. http://dx.doi.org/10.36501/0197-9191/21-018.
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Industrial soil contamination is frequently unearthed by transportation agencies during construction within the right-of-way. As a result, transportation agencies may experience construction delays. Soils co-contaminated with high-molecular-weight polycyclic aromatic hydrocarbons (HMW-PAHs) and metals are commonly encountered in Illinois and exhibit recalcitrance towards conventional treatment technologies. This issue is exacerbated in the fine-grained soils common to Illinois, where low-permeability and immense sorption capacity increase treatment complexity, cost, and duration. Contaminated sites are spatially and temporally restrictive and require rapid in situ treatments, whereas conventional soil remediation requires 1 to 3 years on average. Consequently, transportation agencies typically pursue excavation and off-site disposal for expediency. However, this solution is expensive, so a comparatively expeditious and affordable treatment alternative is needed to combat the increasing cost of hazardous waste disposal. The objective of this work was to develop an accelerated in situ treatment approach adaptable for use at any construction site to cost-effectively remove HMW-PAHs and metals from clayey soil. It was hypothesized that an in situ electrochemical treatment which augments electrokinetics with H2O2 could remediate both HMW-PAHs and metals in less than a month. Bench-scale reactors resemblant of field-scale in situ electrokinetic systems were designed and fabricated to assess the electrochemical treatment of clayey soils contaminated with HMW-PAHs and metals. Pyrene, chromium, and manganese were used as model contaminants, spiked into kaolinite as a model clay. Electrokinetics were imposed by a low-intensity electrical field distributed by graphite rods. Electrolytic H2O2 systems were leveraged to distribute electrical current and facilitate contaminant removal. Average contaminant removals of 100%, 42.3%, and 4.5% were achieved for pyrene, manganese, and chromium, respectively. Successful development of this bench-scale treatment approach will serve to guide transportation agencies in field-scale implementation. The results from this work signify that electrochemical systems that leverage eco-friendly oxidant addition can replace excavation and disposal as a means of addressing clayey soils co-contaminated with HMW-PAHs and metals.
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Ameri, Samuel y Patrick Szary. PB2006105744 Needs for Oil and Gas Pipeline Safety and Security. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), enero de 2005. http://dx.doi.org/10.55274/r0012127.
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Pipelines are by far the most important mode of petroleum transportation in the United States because of their remarkable efficiency and low transportation cost. Pipelines carry two-thirds of the energy consumed by our nation and are recognized as the safest and most economical way to distribute vast quantities of oil and gas from production fields to refineries to consumers for a foreseeable future. This sophisticated network of gathering and distribution systems comprises 2.3 million miles of pipelines-varying in size from 2 inches to 60 inches in diameter. Pipelines are vital to a nation's economy and are a significant part of national critical infrastructure. The pipeline infrastructure and the volume of products transported have continued to grow as demand for energy has increased. Over the next two decades, the demand for energy is projected to reach record levels. This increased demand for energy combined with the expansion of the cities and suburban areas will require the pipeline infrastructure not only to expand but to reliably and safely deliver energy services in support of the nation's economy. The United States has a well-developed system for the protection of the public and the environment from the dangers of oil and gas pipeline failures. However, there is always a chance that a pipeline can leak. Pipeline leaks can be dangerous to people, to the natural environment, to public land, and to private property. Furthermore, the tragic events of the September 11 t terrorist attacks have focused the attention on the security of the nation's energy sources and the critical energy and transportation infrastructure systems. Therefore, pipeline security and safety has become a high-profile, national concern.