Academic literature on the topic 'Verticale structure'

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Journal articles on the topic "Verticale structure"

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Constantatos, Christos, and Stylianos Perrakis. "Différenciation verticale et structure du marché." Survol de la littérature 71, no. 1 (2009): 71–98. http://dx.doi.org/10.7202/602167ar.

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RÉSUMÉ L’objectif de ce travail est de faire un survol des progrès récents sur la structure des marchés où se retrouvent plusieurs qualités du même produit. L’accent est mis sur les cas où les consommateurs demeurent unanimes quant au classement des produits, si ces derniers sont offerts à des prix reflétant les augmentations du coût moyen nécessaires pour l’amélioration de leur qualité. Les considérations stratégiques du choix des qualités sous des hypothèses alternatives, quant à la nature du coût fixe ainsi qu’en présence de firmes à plusieurs produits, sont aussi examinées.
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DionneI, Jean-Claude, and Augusto Pérez Alberti. "Structures cylindriques verticales dans un dépôt meuble Quaternaire, en Galice (Espagne)." Géographie physique et Quaternaire 54, no. 3 (2002): 343–49. http://dx.doi.org/10.7202/005640ar.

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RésuméCette note signale pour la première fois l'existence de structures cylindriques verticales dans un dépôt quaternaire, en Espagne. Les deux structures observées se trouvent dans un dépôt limonosableux dans une vallée près de la frontière entre la Galice et la Castille-León, au NO de la péninsule ibérique. La structure principale mesure plus de 225 cm de hauteur, 15 cm de largeur à la base, 20-25 cm à la partie centrale et une quarantaine de centimètres au sommet. Le tiers inférieur est essentiellement sableux et caractérisé par des couches circulaires. La section centrale comprend deux cônes superposés et partiellement emboîtés, remplis de petit gravier sableux, alors que le tiers supérieur de la structure verticale, qui pénètre dans un dépôt de rudites, est essentiellement grossier. Les deux structures cylindriques verticales sont attribuées à des sources ascendantes créées par la pression hydrologique dans le dépôt glacio-lacustre lors de la mise en place de la nappe alluviale d'origine fluvio-glaciaire. Les structures sont vraisemblablement contemporaines de la formation de la nappe alluviale.
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Poret, Sylvaine. "Structure verticale d'un reseau de distribution de drogues illicites et politique repressive optimale." Recherches économiques de Louvain 71, no. 4 (2005): 391–412. http://dx.doi.org/10.1017/s0770451800005704.

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RésuméCet article s'attache à donner des fondements théoriques à la structure verticale des réseaux de distribution des drogues illicites, en faisant appel à l'analyse des relations verticales et en intégrant le caractère illégal de cette activité. Il analyse ensuite la manière dont les autorités, par l'intermédiaire des coûts de répression qu'elles imposent aux vendeurs de drogues, peuvent mettre en œuvre dans le cadre d'un équilibre décentralisé l'optimum social. Nous montrons qu'un réseau verticalement séparé, structure optimale de premier rang, très couramment observée sur ce marché, ne peut jamais être mis en œuvre.
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LLERENA, Patrick, and Ehud Zuscovitch. "Valeur d’option et structure de marchés : le cas du quasi-monopole." Économie appliquée 40, no. 1 (1987): 97–113. http://dx.doi.org/10.3406/ecoap.1987.4092.

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Dans des structures oligopolistiques interdépendantes, lorsque la demande finale est aléatoire, un risque de rupture d’approvisionnement de consommations intermédiaires apparaît. Une valeur d’option sera incorporée au prix du marché et, ainsi en l’absence d’une intégration verticale, l’accroissement de la flexibilité de long terme est payé par une baisse de l’efficacité à court terme.
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Ouahsine, Abdellatif. "Structure verticale des ondes longues océaniques en présence de points tournants." Comptes Rendus de l'Académie des Sciences - Series IIB - Mechanics 329, no. 2 (2001): 109–15. http://dx.doi.org/10.1016/s1620-7742(00)01293-9.

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Allen, Nicholas J. "Romulus et Bhîshma. Structures entrecroisées1." Anthropologie et Sociétés 29, no. 2 (2005): 21–44. http://dx.doi.org/10.7202/011893ar.

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Résumé Cette contribution se situe dans la tradition du comparatisme indo-européen de Georges Dumézil. On essaye de rapprocher Romulus, fondateur mythique de Rome, et Bhîshma, grand-père classificatoire des héros guerriers du Mahâbhârata (épopée sanskrite). Tous deux sont associés aux dieux dans la ligne du *Dyeus indo-européen, et tous deux se trouvent engagés dans des séries pentadiques. Dans un sens « vertical », Romulus ouvre la liste des rois de Rome, tandis que Bhîshma ouvre la liste des maréchaux Kaurava. Dans un sens « horizontal », leur vie à tous deux se déroule en cinq phases, et si Romulus a cinq associés, Bhîshma a quatre frères. L’analyse de ces séries met en évidence un schéma pentadique – expansion du schéma trifonctionel de Dumézil. L’entrecroisement des séries verticale et horizontale forme une structure complexe, dans le prolongement d’une tradition indo-européenne très ancienne.
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Doussin, Jean-François. "Un aéronef urbain pour explorer la structure verticale de la pollution atmosphérique." La Météorologie, no. 107 (2019): 15. http://dx.doi.org/10.4267/2042/70548.

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Poret, Sylvaine. "Structure verticale d'un réseau de distribution de drogues illicites et politique répressive optimale." Recherches économiques de Louvain 71, no. 4 (2005): 391. http://dx.doi.org/10.3917/rel.714.0391.

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Boucher, Y., and L. Gayraud. "Émission spontanée amplifiée (ÉSA) dans une structure à double cavité verticale (Bi-VCSEL)." Journal de Physique IV (Proceedings) 119 (November 2004): 135–36. http://dx.doi.org/10.1051/jp4:2004119024.

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Lanmafankpotin, Georges, and Pierre André. "Arènes décisionnelles dans les régimes coutumiers du Bénin et territorialité de la participation." Cahiers de géographie du Québec 59, no. 168 (2016): 407–32. http://dx.doi.org/10.7202/1037256ar.

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Deux grands ensembles socioculturels de gestion traditionnelle du pouvoir, au Bénin, couvrent différentes réalités participatives selon que les décisions se prennent dans une société hiérarchisée à structure verticale ou dans une société acéphale à structure horizontale. À l’intérieur de ces structures et en fonction des aires culturelles, les dispositifs participatifs peuvent aller des plus simples et démocratiques aux plus complexes et très réservés à une clientèle particulière. On distingue leDaŋnoude Sètrah, lesHon-Togbassa,TokplékpléetTogbéssod’Abomey, l’Atunşede Kétou et l’Aruzumade Nikki. Ces dispositifs visent l’amélioration de l’efficacité de la gouvernance par l’association du citoyen à la prise de décision et par l’acquisition de l’onction populaire à l’action publique. Dans ces sociétés à gestion communautaire du type de celles rencontrées au Bénin, la participation rythme la vie, et les décisions prises sont en général largement partagées, quoique des mécanismes institutionnalisés soient en place pour assurer que chaque membre de la communauté se retrouve dans les décisions qui engagent l’ensemble des populations.
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Dissertations / Theses on the topic "Verticale structure"

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Perez, Gaëtan. "Caractérisation de diodes Schottky en diamant de structure pseudo-verticale." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAT051/document.

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Le diamant est souvent défini comme le matériau ultime pour la réalisation de composants à semi-conducteurs pour des applications d'électronique de puissance. Bien que plusieurs interrupteurs de puissance en diamant soient parus à l'échelle mondiale, ils sont à l'heure actuelle à l'état de prototype et de preuve de concept. Il est donc nécessaire de comprendre leurs mécanismes de fonctionnement afin de pouvoir utiliser tout leur potentiel dans des convertisseurs de puissance. Dans cette thèse, l'analyse se focalise sur des diodes Schottky en diamant de structure pseudo-verticale. Des caractérisations statiques et en commutation des diodes Schottky ont tout d'abord été réalisées. Elles ont permis d'extraire les caractéristiques des composants et de les intégrer dans des convertisseurs de puissance afin d'analyser leur comportement en commutation. L'utilisation et la gestion des diodes dans des convertisseurs ont ensuite été étudiées. Ces études ont permis de proposer des modifications de la structure des diodes afin d'améliorer la performance de leur intégration dans des convertisseurs de puissance. Finalement l'analyse théorique des performances d'une diode Schottky en diamant dans un convertisseur est réalisée. La comparaison entre ces performances et celles d'une diode Schottky en SiC a permis de mettre en évidence les particularités des composants en diamant ainsi que les bénéfices qu'ils peuvent apporter à l'électronique de puissance<br>Diamond is considered as the ultimate semiconductor for power electronics applications. Even if diamond semiconductor devices have been realized worldwide, it is still prototype or proof of concept devices. It is then necessary to understand how do they operate to use their entire benefits in power converters. In this thesis, we focused the analysis on pseudo-vertical diamond Schottky diodes. Firstly, static and switching characterizations have been realized. They allow us to extract devices characteristics in the way to integrate them in power converters to analyze their switching abilities. Management of diodes in power converters is then studied. These studies allow us to propose device structure modifications in the way to improve diodes performances and their integration in power converters. Finally, a theoretical analysis on a diamond Schottky diode performances in a power converter is realized. It has been compared to the performances of a SiC Schottky diode. It highlights the particularities of diamond devices and the benefits they might bring to power electronics applications
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Pianezze, Joris. "Modélisation de la structure verticale de la turbulence optique en milieu naturel." Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-00830505.

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Les milieux complexes sont une source d'incertitude importante notamment lorsqu'il s'agit de développer des modèles climatique ou météorologique. Le développement de la couche limite atmosphérique à l'intérieur d'une vallée encaissée, incluant des vents de vallée et de pente, n'est, par exemple, pas résolu, ce qui a un impact considérable sur la prévision de la convection, du transport de polluants, etc... La simulation des grandes échelles de la turbulence (SGE) est un outil qui a montré sa capacité à reproduire finement les structures turbulentes dans ce type de contextes au travers des approches idéalisées. L'extension de la SGE aux milieux naturels est réalisée dans cette thèse qui s'articule en trois parties. La première partie présente les équations et les notions nécessaires à la compréhension des problèmes de turbulence dans la couche limite atmosphérique. On s'attache à décrire le cadre des lois issues de la théorie des similitudes et le cadre de la turbulence optique. La seconde partie présente des résultats issus de deux simulations idéales dans lesquelles nous comparons les résultats issus de la simulation avec d'une part les lois issues de la théorie des similitudes et d'autre part les données radar disponible lors de la campagne IHOP. L'utilisation d'un maillage raffinée près du sol permet d'améliorer les profils verticaux des champs turbulents en améliorant la prédiction des gradients à l'interface sol/atmosphère. De plus, le profil de couche limite est bien reproduit par les profils du paramètre de structure des fluctuations de l'indice de réfraction de l'air simulé si on compare avec les résultats issus du radar. Globalement, la dynamique des champs turbulents résolus par le modèle reproduise une dynamique et des ordres de grandeurs corrects conformes à nos attentes. Une fois l'évaluation du modèle effectuée, une simulation a été mise en place autour de la campagne d'observation VOTALP située dans le sud de la Suisse. Cette simulation comprend 5 domaines emboités allant de 16 kms de résolution horizontales pour le plus grand domaine à 100m pour le plus petit domaine. L'important dispositif déployé durant la campagne VOTALP située dans une vallée dans le sud de la Suisse a permis de confronter les résultats issus de la modélisation à haute résolution avec ces données d'observation. Les résultats obtenus ont, entre autre, montré que la simulation à haute résolution est un outil adapté pour l'étude des phénomènes de basses couches et notamment la turbulence optique en milieu complexe.
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Pegliasco, Cori. "Structure verticale des tourbillons de mésoéchelle dans les quatre grands systèmes d'upwelling de bord est." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30331/document.

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Basé sur l'analyse conjointe et complémentaire de ~10 ans de données altimétriques et de profils verticaux de température et de salinité acquis par les profileurs Argo, l'objectif principal de cette thèse est d'étudier en détail les caractéristiques de surface et la structure verticale des tourbillons dans les 4 grands systèmes d'upwelling mondiaux (EBUS Pérou-Chili, Californie, Canaries et Benguela), qui partagent une dynamique à grande échelle relativement similaire. Les résultats principaux montrent que l'ensemble des tourbillons détectés sur les cartes altimétriques dans les 4 EBUS ont des propriétés physiques relativement proches, avec une forte proportion de tourbillons de faibles dimensions ayant une durée de vie relativement courte. Au contraire, la faible partie des tourbillons échantillonnés par les profileurs Argo montre des dimensions bien plus grandes pour des durées de vie plus longues. La sur-représentation de ces grandes échelles dans le jeu des tourbillons échantillonnés par les profileurs Argo est donc le biais majeur des résultats obtenus sur la structure verticale des tourbillons. L'analyse des profils moyens d'anomalies de température et de salinité acquis par les profileurs Argo dans les tourbillons révèle une forte hétérogénéité entre les 4 EBUS, mais également au sein de chacun de ces systèmes d'upwelling. Les structures verticales des tourbillons sont fortement liées à l'hydrologie et à la dynamique locale. Par exemple, les tourbillons de subsurface du PCUS occupent plutôt la partie Sud du système, alors que les tourbillons intensifiés en surface sont présents à la limite Nord de la gyre subtropicale. Dans le CALUS, la présence de Cuddies se devine à la côte, les autres sous-régions contenant des tourbillons dont les anomalies sont majoritairement intensifiées à la base de la pycnocline, avec comme particularité un changement de signe lié à la salinité des couches superficielles. Le CANUS est peuplé de tourbillons très différents en fonction de leur position par rapport à la zone frontale du Cap Vert : au Nord, des tourbillons intenses en subsurface, avec la présence de quelques Meddies ; au Sud, des tourbillons très superficiels. De même dans le BENUS, la partie au Nord de 15°S contient plutôt des tourbillons intensifiés dans les couches de surface, alors qu'au Sud du front d'Angola-Benguela, les tourbillons présentent des anomalies fortes sur une grande partie de la colonne d'eau. L'extrême Sud de cet EBUS est également le lieu de passage des Anneaux des Aiguilles. Les contributions de l'advection isopycnale et du déplacement de la colonne d'eau sur la verticale nous permettent d'affiner la description de ces différentes structures. La présence de grands types de tourbillons, à la morphologie bien distincte (cœur de surface, de subsurface, grande extension verticale, tourbillons fortement intensifiés, etc.), est confirmée par l'étude des tourbillons spécifiquement générés dans la bande côtière. L'analyse Lagrangienne de ces tourbillons nous permet également de décrire l'évolution temporelle de leur structure verticale, qui montre une homogénéité temporelle inattendue. Cette thèse présente donc plusieurs outils facilement applicables dans différentes régions océaniques pour caractériser la structure thermohaline des tourbillons et fournit pour la première fois une description des grands types de tourbillons peuplant les EBUS, soulignant la grande diversité de la mésoéchelle<br>Merging ~10 years of altimetry maps and vertical profiles provided by Argo floats, we aim to study in details the eddy's surface characteristics and vertical structure in the 4 major Eastern Boundary Upwelling Systems (EBUS : Peru-Chile, California, Canaries and Benguela), sharing similar large-scale dynamics. Our main results show that the eddies detected on altimetry maps in the 4 EBUS have close physical properties, with a lot of small-scale structures (radius &lt; 40km, amplitude &lt; 1cm and lifetime &lt; 30 days). In contrast, the few eddies sampled by Argo floats have larger dimensions (radius of ~90-140 km, amplitude of ~3-7 cm) and longer lifetimes (6-10 months). The major bias with the analyzed vertical structure is the over representation of these large-scale eddies. The temperature and salinity anomaly mean profiles acquired by Argo floats surfacing within eddies reveals a strong heterogeneity between each of the 4 EBUS, but also within them. The eddies' vertical structure is strongly influence by the local hydrology and dynamics. For example, the subsurface-intensified eddies of the PCUS tend to be located in the Southern part of this EBUS, while the surface-intensified eddies are preferentially located near the Northern boundary of the subtropical gyre. In the CALUS, we can identify Cuddies in some coastal sub-regions, but in this EBUS, most of the eddies are intensified at the base of the pycnocline, with a reversal of the salinity anomaly compared to the surface layers. In the CANUS, the Cape Verde frontal zone separates distinct subsurface-intensified eddies and some Meddies in the North, from the Southern part, where eddies are surface-intensified. In the same way, the Angola-Benguela Front of the BENUS separates the surface-intensified eddies in the North from strong, deep-reaching anomalies in the South. The Southern-most part of the BENUS is also a preferential pathway for the large Agulhas Rings and their associated cyclones. The respective contributions of isopycnal advection and vertical displacement improve the description of these very diverse structures. The presence of several eddy-types, with distinct thermohaline properties (surface or subsurface-intensified, deep vertical extend, intense or not, etc.) is confirmed by the study of eddies generated in the coastal area of each EBUS. Their Lagrangian analysis allows us to describe the temporal evolution of their vertical structure, which shows an unexpected temporal homogeneity. This manuscript presents different efficient tools used to analyze the surface characteristics, the thermohaline properties and the temporal evolution of mesoscale eddies in the 4 major EBUS, highlighting their diversity
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Simonot, Timothé. "Conception et hybridation de l'environnement électronique des composants de puissance à structure verticale." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00733677.

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Ces travaux de thèse portent sur l'intégration hétérogène des fonctions de commande pour des transistors de puissance verticaux à grille isolée. Ce travail a consisté en la conception des fonctions de commande pour un transistor de type MOSFET en technologie CMOS planar, puis en la conception du composant de puissance lui-même, incluant des fonctions spécifiques pour l'auto-alimentation de sa commande. Le deuxième aspect de ce travail est l'étude et la réalisation technologique de métallisations épaisses en surface de puces silicium pour l'hybridation en chip on chip de la partie commande et de la partie puissance. Ce mémoire de thèse comporte trois chapitres équivalents : études théoriques et présentation des concepts, conception et validation expérimentale de la partie commande puis conception de la partie puissance et développements technologiques. Les champs d'application de ces travaux sont variés car ils couvrent un large domaine de l'électronique de puissance (convertisseurs hybrides).
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Simonot, Thimothé. "Conception et hybridation de l'environnement électronique des composants de puissance à structure verticale." Thesis, Grenoble, 2011. http://www.theses.fr/2011GRENT127/document.

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Ces travaux de thèse portent sur l'intégration hétérogène des fonctions de commande pour des transistors de puissance verticaux à grille isolée. Ce travail a consisté en la conception des fonctions de commande pour un transistor de type MOSFET en technologie CMOS planar, puis en la conception du composant de puissance lui-même, incluant des fonctions spécifiques pour l'auto-alimentation de sa commande. Le deuxième aspect de ce travail est l'étude et la réalisation technologique de métallisations épaisses en surface de puces silicium pour l'hybridation en chip on chip de la partie commande et de la partie puissance. Ce mémoire de thèse comporte trois chapitres équivalents : études théoriques et présentation des concepts, conception et validation expérimentale de la partie commande puis conception de la partie puissance et développements technologiques. Les champs d'application de ces travaux sont variés car ils couvrent un large domaine de l'électronique de puissance (convertisseurs hybrides)<br>The work presented in this PhD manuscript deals with heterogeneous integration of the control functions for driving a vertical power MOSFET. This work consisted in the design of the driving functions for a vertical power MOSFET in a planar CMOS technology, then in the design of the power transistor itself, including specific functions for the self powering of its driving circuitry. The second aspect of this work was the technological study and realization of thick metallization at the surface of silicon dies for the chip on chip assembly of the control and the power parts. This manuscript is composed of three equal chapters: the theoretical study and concepts presentation, the design and experimental validation of the driver part, and the design of the power part and the technological realizations. The field of application of this work covers a large spectrum as it concerns every hybrid converter
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Zwiebel, Jimmy. "Etude de l'impact orographique sur la structure microphysique horizontale et verticale des précipitations." Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22642/document.

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Au cours de l’automne 2012, un réseau d’observation très complémentaire a été déployé dans la région des Cévennes pour la période d’observation spéciale (SOP) du projet HyMeX. Ce réseau d’observation a été spécifiquement élaboré afin d’étudier la structure et l’hétérogénéité des précipitations et en particulier, l’impact du relief sur cette structure. Dans un premier temps, l’analyse de la distribution des gouttes de pluie (DSD) au sol et le long d’un profil vertical à partir des observations nous permet de décrire précisément la structure des précipitations le long d’un gradient topographique. Afin de comprendre l’influence du relief sur cette structure, nous nous concentrons sur les processus microphysique associés à la structure des précipitations. Pour ce faire, nous définissons trois régimes de pluie et étudions l’évolution verticale de la DSD le long du gradient topographique. Les variations en nombre ou en taille dans la DSD peuvent être associées à différents processus microphysiques ou dynamiques. Pour finir, nous estimons la capacité d’un modèle paramétré de l’atmosphère tel que WRF à représenter la structure des précipitations et les processus associés dans une zone de montagne<br>During Fall 2012, a complementary observational network has been deployed in the Cévennes region (South of France) for the Special Observation Period (SOP) of the HyMeX project. This network has been specifically designed to study the structure and heterogeneity of precipitations and, in particulat, the impact of orography on this structure. Firstly, the analysis of the Drop Size Distribution (DSD) at the ground et along a vertical profile from ground observations allow us to describe precisely the rainfall structure along a topographical gradient. In order to understand the influence of a relief on this structure, we focus our study on the microphysical process associated with the structure of precipitations. To do so, we define three rainfall regime et study the vertical evolution of the DSD along the topographical gradient. Variations in number and size of the DSD can be associated with different microphysical or dynamical process. Finally, we estimate the capacity of a bulk atmospheric model such as WRF to represent the rainfall structure and associated mechanisms above a mountainous area
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Pignoux, Stéphane. "Structure interne d'un jet de gaz injecté perpendiculairement à une couche limite turbulente verticale d'eau." Poitiers, 1998. http://www.theses.fr/1998POIT2293.

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L'etude de l'injection de gaz dans un fluide anime d'un mouvement perpendiculaire au precedent offre un interet certain aussi bien sur le plan industriel (refroidissement d'aubes de turbines, sustentation d'avions a decollage vertical ou atterrissage court, dispersion de polluants), que sur celui de la securite (fuites de vapeur d'eau dans du sodium). Dans ce travail, nous nous interessons aux jets diphasiques (gaz-liquide) soumis a un courant traversier. Plus precisement, notre etude porte sur un jet d'air circulaire debouchant horizontalement dans une couche limite turbulente verticale d'eau. Son objectif est d'avoir une meilleure comprehension de ses caracteristiques principales comme sa forme exterieure, sa structure interne ou ses interactions avec le milieu environnant. La visualisation du jet et la detection locale de la nature des phases au moyen d'une sonde optique ont montre l'existence d'une poche de gaz de grande dimension entouree d'une mince couche de melange diphasique dans sa premiere partie suivie d'une zone de melange intense tres lumineuse. En aval de cette derniere, le jet perd sa coherence et des paquets du melange gaz-liquide sont entraines par le courant liquide. L'analyse des images a permis de montrer une croissance lineaire de l'aire de la section du jet dans la premiere partie de l'ecoulement. Ce resultat est similaire a celui obtenu pour un jet homogene ayant un mecanisme totalement different. La mesure du taux de presence du gaz a mis en evidence la structure interne du jet. La poche de gaz est entouree d'une interface gaz-liquide d'une epaisseur egale a 5 mm. L'interaction entre le jet et le milieu environnant a ete etudiee en mesurant le champ de vitesse dans le plan de symetrie du jet. La zone en amont de l'injection est fortement perturbee par celui-ci. Il se comporte comme un obstacle solide : l'ecoulement liquide subit une forte deviation au voisinage de l'injection, les fluctuations de vitesse augment considerablement dans cette zone. En revanche, dans la region aval, le jet peut etre considere comme un obstacle souple : il n'existe pas de fort gradient de vitesse du liquide a sa frontiere. Par ailleurs, le mecanisme de rupture de la poche de gaz donc du jet en lui-meme est dependant de la vitesse du gaz a l'interieur de la poche et de la vitesse du liquide autour du jet.
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LAWNCZAK, FABRICE. "Structure de l'ecoulement dans la colonne verticale de pompage de faible hauteur d'une pompe airlift." Université Louis Pasteur (Strasbourg) (1971-2008), 1999. http://www.theses.fr/1999STR13092.

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La presente etude se propose de caracteriser les ecoulements air-eau, dans la colonne verticale de relevage d'une airlift pump atmospherique quelque peu inhabituelle : outre une tres faible hauteur de relevage, elle a la particularite de posseder en entree de colonne un convergent dans lequel un injecteur d'air conique peut se deplacer. La conjonction pour le moins unique de ces deux caracteristiques dans l'etude des ecoulements diphasiques en colonne verticale, va amener a considerer un regime d'ecoulement particulier. L'outil principal de cette caracterisation est une double sonde optique. Il est mis en exergue que les resultats obtenus devient notablement des predictions theoriques classiques a partir d'une certaine limite et que cette deviation peut s'interpreter dans le sens d'une transition specifique a notre airlift pump, caracterisee par la persistance d'un regime d'ecoulement de type poches-bouchons non conventionnel pour des conditions de fonctionnement ou le regime bouillonnant est normalement predit. L'etude hydrodynamique aboutit a une nouvelle equation constitutive d'ecoulement aux forts debits d'air qui est injectee dans un modele cellulaire d'ecoulement standard poches-bouchons. La modelisation predit alors correctement toutes les donnees experimentales et valide le modele cellulaire au dela du cas classique du regime poches-bouchons. L'etude se conclue sur une methode experimentale originale permettant une visualisation tridimensionnelle de l'ecoulement dans des regimes qui jusqu'alors echappaient a une description fine.
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Vladimirova, Kremena. "Nouveaux concepts pour l'intégration 3D et le refroidissement des semi-conducteurs de puissance à structure verticale." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00738000.

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L'électronique de puissance est en pleine mutation matérielle, technologique et conceptuelle. Cette évolution bouscule l'approche traditionnelle de la conception et de la fabrication des convertisseurs statiques avec pour objectif de proposer des solutions plus performantes, plus fiables et plus compactes et tout cela dans un contexte technico économique de plus en plus exigeant. Cette thèse analyse et expérimente un concept innovant de terminaisons en tension verticales ouvrant la voie vers l'intégration en 3D des composants de puissance mais également l'intégration, au sein même de la zone active d'un échangeur thermique. En s'appuyant sur la technique de réalisation des tranchées profondes issue de la micro électronique, ce document présente une approche permettant la co-intégration de plusieurs composants de puissance indépendants partageant la même électrode et le même substrat en face arrière. L'autre volet de ce travail de thèse est focalisé sur le concept DRIM Cooler (Drift Region Integrated Microchannel Cooler), un réseau de microcanaux perpendiculaires au plan de jonction du composant de puissance permettant son refroidissement direct. Les analyses numériques sont complétées par de nombreuses réalisations, caractérisations et mises en œuvre des approches précitées.
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Dewitte, Boris. "Rôle de la structure verticale de l'océan sur la variabilité basse fréquence dans le Pacifique tropical." Toulouse 3, 1998. http://www.theses.fr/1998TOU30296.

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Nous étudions dans cette thèse la variabilité basse fréquence dans le Pacifique tropical de la structure verticale de l'océan simulée par le modèle de circulation générale du LODYC sur la période 1985-1994. Notre motivation est double : 1) Interpréter la simulation en terme d'ondes longues de Kelvin et de Rossby selon les différents modes barocicles et 2) expliciter les mécanismes liés à la propagation d'énergie verticale et le couplage avec l'atmosphère<br>We investigate the low frequency variability of the oceanic vertical structure in the tropical Pacific from an ocean general circulation (OPA) forced simulation over the period 1985-1994. Our goal is two-fols : 1) To find to which extent the simulation can be interpreted as a combination of baroclinic long equatorial Kelvin and Rossby waves for the different vertical modes, and 2) to document the processes that affect the waves propagation, in particular modal dispersion due to zonal change in the density field, vertical energy propagation processes and the coupling with atmosphere. Linear model simulations are carried out and are used as a diagnostic tool
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Books on the topic "Verticale structure"

1

body, Fondazione OAMi issuing, ed. Milano verticale: Vertical Milan. Fondazione OAMi, 2021.

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Architecture, Dominique Perrault, ed. La ville verticale E+: Énergie positive = E+ vertical city : energy positive. Dominique Perrault architectes, 2017.

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Nussbaumer, François. Bruxelles vertical. Le Noyer, 2018.

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François, Nussbaumer, and Aymard Gilles 1952-, eds. Lyon vertical. Noyer, 2013.

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Halonen, Maija. Endogenous industry structure in vertical duopoly. The Economics of Industry Group, 1994.

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Jacquet-Lagrèze, Romain. Vertical horizon. Asia One Book, 2014.

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Kennedy, David. Vertical structure of the English electricity industry. Chartered Institute of Public Finance and Accountancy, 1996.

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Beke, Frank. Gent verticaal. Le Noyer Edition, 2016.

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Gardner, Elizabeth B. Mesoscale vertical structure of an explosive oceanic cyclone. Naval Postgraduate School, 1991.

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American Society of Civil Engineers. Committee on Waves and Wave Forces. Task Committee on Forces on Inclined and Vertical Wall Structures., ed. Wave forces on inclined and vertical wall structures. American Society of Civil Engineers, 1995.

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Book chapters on the topic "Verticale structure"

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Anderson, David, and Tzu-Wei Fang. "Determining the Longitude Dependence of VerticalE × BDrift Velocities Associated with the Four-Cell, Nonmigrating Tidal Structure." In Ionospheric Space Weather. John Wiley & Sons, Inc., 2016. http://dx.doi.org/10.1002/9781118929216.ch8.

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Satoh, Masaki. "Vertical structure." In Atmospheric Circulation Dynamics and General Circulation Models. Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-13574-3_14.

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Hu, Hong-Song. "Peak Superstructure Responses of Single-Story Sliding Base Structures Under Earthquake Excitation." In Sliding Base Structures. Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-5107-9_4.

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AbstractCompared to multistory sliding base (SB) structures, single-story SB structure is simple and suitable for acquiring the critical parameters influencing the structural response. For this reason, this chapter focuses on the peak superstructure responses of single-story SB structures subjected to three-component earthquake excitation. The influence of the vertical earthquake component and various structural and ground motion characteristics on the peak superstructure response are investigated, and simplified design equations are developed. The developed equations also lay a foundation for the design of multistory SB structures, which will be discussed in the next chapter.
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Busenberg, Stavros, and Kenneth Cooke. "Age and Internal Structure." In Vertically Transmitted Diseases. Springer Berlin Heidelberg, 1993. http://dx.doi.org/10.1007/978-3-642-75301-5_5.

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Volland, Hans. "Vertical Modal Structure." In Atmospheric Tidal and Planetary Waves. Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-2861-9_6.

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Ren, Hongmei, Jianping Zhu, Yanyan Lv, and Weiwei Qin. "Aseismic Design of an Out-of-Code High-Rise Building in Shanghai." In Advances in Frontier Research on Engineering Structures. Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-8657-4_3.

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AbstractProper structural system and performance-based seismic design are the key issues in designing high-rise building structures. This project has unique building facade shape and complex plane function layout, and the structural plane and vertical layout are irregular. The superstructure adopts assembled integral concrete frame-shear wall structure, which is judged as out-of-code high-rise building by seismic review. Firstly, the site conditions, foundation design and structural form selection are introduced. Then, YJK software is used to calculate and analyze the seismic force of the superstructure, and the seismic performance indexes of the structure can meet the requirements of the code. Finally, the regularity of each structural unit of the superstructure is judged, and the corresponding main seismic strengthening measures are put forward.
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Paredaens, Jan, Paul Bra, Marc Gyssens, and Dirk Gucht. "Vertical Decompositions." In The Structure of the Relational Database Model. Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-69956-6_4.

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Kalogeras, Nikos, Joost M. E. Pennings, Gert van Dijk, and Ivo A. van der Lans. "The Structure of Marketing Cooperatives." In Vertical Markets and Cooperative Hierarchies. Springer Netherlands, 2007. http://dx.doi.org/10.1007/1-4020-5543-0_5.

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David, Laurent, Ludovic Chatellier, Dominique Courret, Ismail Albayrak, and Robert M. Boes. "Fish Guidance Structures with Narrow Bar Spacing: Physical Barriers." In Novel Developments for Sustainable Hydropower. Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-99138-8_7.

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AbstractChapter 7 deals with the fish guidance structures (FGS) with narrow bar spacing and focuses on both vertically inclined and horizontal bar racks as well as vertically inclined perforated plate with bypass systems. These FGSs are physical barriers and placed in front of a water intake with either vertical or horizontal angle to the flow direction. They protect fish from entering the water intakes and guide them to the bypass systems and hence into the tailwater. They are suitable for small-to-medium size hydropower plants with design discharge less than 120 m3/s. In the following, different types of FGSs with narrow bar spacing are introduced and their fish guidance performance, head loss prediction and design recommendations presented.
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Worren, Nicolay. "Defining the vertical structure." In Organization Design. Routledge, 2018. http://dx.doi.org/10.4324/9781315145112-6.

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Conference papers on the topic "Verticale structure"

1

Robeson, Mark. "Structural Multifunctionality for Weight Reduction." In Vertical Flight Society 74th Annual Forum & Technology Display. The Vertical Flight Society, 2018. http://dx.doi.org/10.4050/f-0074-2018-12883.

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The US Army's Aviation Development Directorate (ADD) has successfully collaborated with its industry partners to reduce system parasitic weight for aviation platforms through multifunctional structures technology development. In short, this can be generalized as achieving weight savings by replacing the combination of aircraft structure and an independent, add-on mission enabler with a singular system that performs the functions of both structure and mission enabler. This extensive multifunctional technology development for aviation structural applications has yielded significant weight savings over parasitic designs. Technologies demonstrating this structural multifunctionality for weight reduction include integrally armored helicopter floor, lightweight integrally armored helicopter floor, lightning-protected structure, structural antenna aperture, helicopter empennage antenna structure, combat tempered aft fuselage, blast attenuating aircraft structure, and highly durable floor armor for rotorcraft. The significance of weight savings that can be enabled via multifunctional structures technology development is clear. One case study exercise indicates a platform-level mission enabler weight savings of 17.8%. This significance of weight savings is analogous to other studies showing synergistic benefits from technology integration at the technology and system (platform) level.
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Fang, Eugene, Jessica Zhang, Anisur Rahman, Jim Lua, and Nam Phan. "A Multiscale Bondline Damage Characterization and Hybrid Analysis Approach for Adhesively Bonded Composite Structures." In Vertical Flight Society 71st Annual Forum & Technology Display. The Vertical Flight Society, 2015. http://dx.doi.org/10.4050/f-0071-2015-10261.

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Adhesively bonded composite structures have been used extensively in both DoD and commercial industries. Despite many attractive features of a bonded composite structure, integrity and durability of adhesively bonded composite structures are the primary concerns due to their known sensitivity to environmental conditions and the presence of bondline defects associated with the fabrication and processing of a bonded composite structure. In order to reduce the testing matrix in characterization of properties of a bondline for the residual strength and life prediction of its bonded composite structure, a multiscale approach is developed based on an automatic generation of a representative unit cell of a heterogeneous bondline interface including voids and inclusions. Equivalent cohesive properties are extracted from a nonlinear finite element analysis for a unit cell with variations in size and geometric distribution of voids and inclusions within the bondline. The impact of a bondline quality on a global structural response is explored using a bonded I-beam with an initial delamination flaw subject to 4-point bending.
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Tyrell, Stacey, Mark Robeson, Courtney Kube, Dennis McCarthy, and Ronald Lavin. "Dual-Use Structures: Composite Wing with Structural Antenna Aperture." In Vertical Flight Society 72nd Annual Forum & Technology Display. The Vertical Flight Society, 2016. http://dx.doi.org/10.4050/f-0072-2016-11552.

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Many modern aircraft, including rotorcraft, require conformal antennas and fairings to reduce wind drag, ice accretion, lightning strikes, and impact damage. An innovative composite wing configuration with a structural Ultra High Frequency (UHF) antenna window "aperture" has been developed. The wing is based on variants of lightweight X-Cor® sandwich core technology for durability and damage tolerance, with tailored electromagnetic properties in the aperture region of the wing. This paper presents a brief introduction to helicopter wings, a summary of recent research at Boeing and Army leading to this design, and the development approach used for this project. Structural and electromagnetic analyses are provided, and measurement results of an early prototype are summarized. The emphasis of this paper is on the wing configuration details surrounding the antenna aperture. The approach can be replicated on almost any current or future aircraft or rotorcraft.
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Bolukbasi, Akif, and Richard Weisenburger. "Fluid Structure Interaction of Fuel Tanks and Airframe Structures During a Crash Event." In Vertical Flight Society 80th Annual Forum & Technology Display. The Vertical Flight Society, 2024. http://dx.doi.org/10.4050/f-0080-2024-1173.

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This paper presents the results of a research and development (R&amp;D) effort focused on fluid structure interactions between airframe structures and bladder type fuel tanks during a crash environment. During this R&amp;D effort, fuel tank and surrounding structure crash impact tests were conducted using an innovative test configuration that allowed low-cost fabrication of test articles which represented several different design architectures. LS-DYNA models of the crash test article configurations were also developed and correlated with the tests data. Good correlation between the test data and LS-DYNA analysis results was achieved. The paper also includes recommendations for design of the airframe structures around the fuel tanks based on the fluid structure interaction insights gained from the crash tests and analyses.
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Ho, Eric. "Advanced Approaches to Helicopter Engine System Dynamics." In Vertical Flight Society 70th Annual Forum & Technology Display. The Vertical Flight Society, 2014. http://dx.doi.org/10.4050/f-0070-2014-9626.

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The advancement in the modelling and analysis of the helicopter/engine as a system can help to better understanding the vibrations and loads in the overall structure. The linear and rotor induced non-linear dynamic response of the helicopter coupling with its gas turbine engines under the main gear box vibration, engine rotor unbalance, inadvertent release of rotating mass and foreign object ingestion must be considered in the design of the structures. Custom-developed and commercially available tools combined together as a total system prediction process can more accurately evaluate overall structural vibrations and dynamic responses. The analysis also takes into consideration the material non-linearity, large deformation and damping. The fidelity of the prediction system is greatly enhanced by calibration with helicopter and engine test data. As a result, the prediction of structural loads and vibrations at the mount interfaces, engine casings and helicopter structures are made available up-front in the design cycle to help critical structural evaluations. The advancement of a system prediction method is also the prerequisite to address overall helicopter/engine safety and reliability, and to reduce noise.
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Chiu, Lisa, Mark Robeson, Kenneth Hunziker, and Clark Andrews. "Analysis of Shockwave Tolerant Features for Small-Volume Composite Rotorcraft Structure." In Vertical Flight Society 72nd Annual Forum & Technology Display. The Vertical Flight Society, 2016. http://dx.doi.org/10.4050/f-0072-2016-11546.

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The capability for candidate shockwave tolerant features to contribute to shockwave attenuation and residual structural integrity of small-volume rotorcraft structures was evaluated in this study. To first understand the shockwave reflection and transmission effects of an explosive event on small-volume enclosed geometry, Finite Element Analysis (FEA) was performed to assess the relationship between the enclosed volume and explosive energy. The FEA techniques included a fluid dynamics based Arbitrary Lagrangian Eulerian (ALE) method as well as an empirically based method. With an understanding of the pressure environment, analysis was then performed to compare the structural response of representative structure with and without shockwave tolerant features. The shockwave tolerant features identified for this study can be classified as attenuating and reinforcing. Attenuating shockwave tolerant features include sandwich structures while reinforcing features include stitched composites, hybrid laminates, tailored ply orientations, and out-of-plane features. Finally, the paper concludes with discussion of a planned small-volume composite test program to validate the analytical findings and demonstrate the benefits of the shockwave tolerant features.
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Hall, Asha, Mulugeta Haile, Robert Haynes, Michael Coatney, and Jin Yoo. "Structural Health Sensing of Damage Precursors using Magnetostrictive Particles Embedded in Composite Structures." In Vertical Flight Society 70th Annual Forum & Technology Display. The Vertical Flight Society, 2014. http://dx.doi.org/10.4050/f-0070-2014-9639.

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Over the last two decades, tremendous progress has been made in structural health monitoring (SHM) using various sensing techniques such as acoustic emission, eddy current, strain gages, to diagnose damage in aerospace, mechanical and civil infrastructures. Despite this progress, there are still many challenges to address in SHM. Among these challenges is detection of precursors to matrix cracking, fiber/matrix debonding, and delamination. Magnetostrictive smart materials such as Terfenol-D (Tb0.3Dy0.7Fe1.92) (Etrema Products Inc., IA, USA) have proven useful as non-contact strain sensors using Hall Effect or pick-up coil to measure change in magnetization due to strain. In this study, our team will conduct a specific number of fatigue cycles at 1, 100, 1,000, 10,000, 100,000, and 1,000,000 cycles. After each fatigue loading a destructive examination of the specimen surface will be conducted by Scanning Electron Microscope (SEM). By this systematic evaluation, the phenomenon of crazing, the propagation of micro-cracks and delaminations, and the factors that lead to catastrophic failure will be investigated, thereby enabling correlation of the current damage state to the magnetization.
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Gupta, Mohit, Dineshkumar Harursampath, Sathiskumar Ponnusami, Dhamotharan Veerasamy, Shashank Agrawal, and Sangheetha Ponnusami. "Blending Modern Multifunctional Materials with Traditional Structures: An Approach for a Greener and Cleaner Future." In Vertical Flight Society 72nd Annual Forum & Technology Display. The Vertical Flight Society, 2016. http://dx.doi.org/10.4050/f-0072-2016-11548.

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The objective of the project is to propose a multifunctional composite material system for next generation rotorcraft's structural components. In particular, a hybrid composite termed as Piezo-Battery Fiber Reinforced Composite (P-BFRC) comprising of piezoelectric and battery fibers is proposed for the rotorcraft blades, which are arranged in an appropriate optimized fashion. The optimized layout will depend on the characteristic of vibrations in the rotor blades and associated structural components. For the fuselage skin panels, use of Battery Fiber Reinforced Composite (BFRC) is proposed. In the rotor blades and the regions where vibration amplitudes are larger, the P-BFRC structure aims to extract electrical energy from the structural vibrations using the piezoelectric panels and store it within the battery panels embedded in the structure itself. In the fuselage, the battery composite skin panels, upon charging from ground station, can serve as power source for operation for several rotorcraft's electrical and electronic components. Importantly, the proposed multifunctional structure is optimized such that the structural characteristics of the existing rotorcraft is not compromised, while simultaneously performing its multiple functions. In other words, introducing such multifunctional material does not increase overall weight nor reduce the structural load carrying capability. In addition, the proposed material system intend to make minimal modifications in the existing system as far as structure and power management systems are concerned, thereby a re-design of entire structural/power system is not necessary. Preliminary analyses have been conducted for to study the energy harvesting and storage characteristics of the multifunctional structure. This work focuses on detailed quantification of energy harvesting and storage capabilities of the proposed multifunctional system through appropriate electro-mechanical models. Altogether, the multifunctional structural system is found to be a promising step towards a cleaner and sustainable aviation.
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Andrews, Clark, Mark Robeson, and Lisa Chiu. "Analysis and Test of Composite Rotorcraft Structure Subject to Ballistic Events." In Vertical Flight Society 73rd Annual Forum & Technology Display. The Vertical Flight Society, 2017. http://dx.doi.org/10.4050/f-0073-2017-12168.

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Predictive analysis is performed on configurations representative of small-volume rotorcraft primary structure. Potential failure points are identified and the design is modified to withstand the incoming ballistic event. Live fire testing is then executed on multiple specimens to validate the analysis method developed in the previous study. Predictive strength analysis is then performed to determine potential residual strength. Finally, cyclic and static residual strength testing is performed on two specimens. The results demonstrate that small-volume aircraft structure can be designed with composite sandwich structures to mitigate ballistic events that are often catastrophic for traditional aircraft structures.
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Gultekin, Ece, Berkay Ozkan, and Evren Eyup Taskinoglu. "Machine Learning Based Stress Prediction Around the Hole of Attachment Lug Structures for Flaw Tolerance Evaluations." In Vertical Flight Society 81st Annual Forum and Technology Display. The Vertical Flight Society, 2025. https://doi.org/10.4050/f-0081-2025-203.

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This study investigates the stress concentration and damage tolerance of lug structures, with an application example using the horizontal tail plane lug of a light utility helicopter. Using Finite Element Analysis (FEA), stress distributions around the lug hole were simulated under varying load conditions to understand how different loading angles and magnitudes affect stress concentrations. A machine learning approach was employed to predict stress distributions based on a dataset generated from FEA simulations. Several regression models were tested and Random Forest Regression model yields the best predictive accuracy among the others. The study also incorporates a flaw tolerance analysis using the NASGRO® software to calculate the crack growth characteristics of the horizontal tail plane lug structure under service loading. The results highlight the importance of stress distribution variability and identifying the most critical point of the lug structure under service loading with changing angle and amplitude. This research provides insights into the structural integrity of lug components under dynamic loading, contributing to more reliable flaw tolerance assessments for aerospace applications using machine learning techniques.
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Reports on the topic "Verticale structure"

1

Bresnahan, Timothy, and Jonathan Levin. Vertical Integration and Market Structure. National Bureau of Economic Research, 2012. http://dx.doi.org/10.3386/w17889.

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Grant, Charles. Diaphragm Walls as Permanent Basement Walls in Regions of High Seismicity. Deep Foundations Institute, 2018. http://dx.doi.org/10.37308/cpf-2012-slwl-1.

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Reinforced concrete structural slurry walls have been used in the United States since the early 1960s. The typical practice, and one that makes the economics of slurry walls particularly attractive, is to design the walls to act as both temporary excavation support and permanent basement walls. They often serve as multi-story basements and below grade parking for buildings, for tunnels, subway stations, and other buried structures. One of the early applications was for a foundation for a subway station in San Francisco, but for the most part they have been used more extensively in regions of low seismicity. The purpose of this report is to investigate the requirements for extension of this practice to more common use in regions of high seismicity. Structural slurry walls are concrete walls constructed below the ground surface. In slurry wall construction, a trench is excavated using a rectangular clamshell bucket or other specialized equipment. During excavation, the trench is held open by introduction of a bentonite or polymer slurry. Steel reinforcement, if required, is lowered into the slurry-filled trench, and concrete is subsequently deposited by tremie, displacing the slurry. The length of trench open at any one time is limited to a typical maximum of about 20 to 24 feet by excavation stability and concrete placement volume considerations. Each individual concrete placement is referred to as a “panel,” and vertical construction joints separate the panels. Temporary “end-stops” are used as formwork to control the geometry of the panel joints, and horizontal reinforcement is discontinuous at the joints. Structural slurry panels range from 1.5 to 5.0 feet thick, 7 to 24 feet long, and up to 300 feet deep. In the United States, panels that are 2.0 to 3.5 feet thick and depths of 40 to 150 feet are commonplace. Structural basement walls support earth pressures acting laterally against the wall, dead and live loads acting vertically, and in-plane shear and flexure from wind and earthquake loads. The design of permanent slurry walls in regions of low or moderate seismicity is often limited to providing the strength necessary to resist out-of-plane soil pressures and vertical dead and live loads from the superstructure and basement framing. Although these walls also transfer in-plane lateral forces from the superstructure into the soils, the walls are often not specifically designed for these in-plane forces because their inherent strength is usually much greater than the forces being transferred. If resistance to in-plane forces acting on a wall required an increase in vertical reinforcement at the ends of a wall segment, an increase in the cap beam strength, or an increase in the horizontal reinforcement for shear strength, the overall design and construction approach would not vary significantly from current practice. Structural slurry walls have been used to a limited extent for buildings designed for high seismic risk, but there is reluctance on the part of design engineers to use them more often because of concern for how to design these walls to resist in-plane lateral forces, lack of code provisions for reinforcement detailing, and damage that may occur at panel joints. For buildings designed for high seismic risk, such as those assigned to Seismic Design Categories (SDC) D, E, and F as defined in Minimum Design Loads for Buildings and Other Structures (ASCE/SEI 7-10), in-plane shear and flexural actions may likely require modifications of a structural slurry wall only designed for out-of-plane soil pressures and vertical live and dead loads. Design would need to address in-plane lateral forces acting on structural slurry walls and the interaction of the in-plane actions with the out-of-plane and vertical actions. These issues are discussed in this report, and approaches to design for high seismic risk are presented.
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Pegau, W. S., and Emmanuel Boss. Remote Sensing of Vertical IOP Structure. Defense Technical Information Center, 1999. http://dx.doi.org/10.21236/ada613927.

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Pegau, W. S., and Emmanuel Boss. Remote Sensing of Vertical IOP Structure. Defense Technical Information Center, 2001. http://dx.doi.org/10.21236/ada624947.

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Jones, Thomas, Richard Strachan, David Mackie, Mervyn Cooper, Brian Frame, and Jan Vorstius. Phase Field & Monte Carlo Potts Simulation of Grain Growth and Morphology of Vertically Upwards Cast Oxygen Free Copper. University of Dundee, 2021. http://dx.doi.org/10.20933/100001287.

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A 2-D Phase-Field coupled Monte Carlo-Potts model, using PhasePot of vertically upwards continuous casting (VUCC) of oxygen free copper (OFCu) was investigated to reveal the grain growth morphology and the withdrawal parameters required to produce a high-quality homogeneity within the grain structure. A dynamic moving reference frame was used as an approximation to the complex withdrawal parameters. The simulation results were validated alongside cast rod grain structures produced under the same cast parameters, at Rautomead Ltd on a RS080 VUCC machine.
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Hyde, Richard A. Vertical Structure of Flow Through Tarifa Narrows. Defense Technical Information Center, 1992. http://dx.doi.org/10.21236/ada276986.

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Zaneveld, J. R., and W. S. Pegau. Vertical Structure of the Inherent Optical Properties. Defense Technical Information Center, 1997. http://dx.doi.org/10.21236/ada627876.

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Stakes, Keith, and Joseph Willi. Study of the Fire Service Training Environment: Safety, Fidelity, and Exposure -- Acquired Structures. UL Firefighter Safety Research Institute, 2019. http://dx.doi.org/10.54206/102376/ceci9490.

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Previous FSRI led research projects have focused on examining the fire environment with regards to current building construction methods, synthetic fuel loading, and best-practices in firefighting strategies and tactics. More than 50 experiments have been previously conducted utilizing furniture to produce vent-limited fire conditions, replicating the residential fire environment, and studying the methods of horizontal ventilation, vertical ventilation, and positive pressure attack. Tactical considerations generated from the research are intended to provide fire departments with information to evaluate their standard operating procedures and make improvements, if necessary, to increase the safety and effectiveness of firefighting crews. Unfortunately, there still exists a long standing disconnect between live-fire training and the fireground as evident by continued line of duty injury and death investigations that point directly to a lack of realistic yet safe training, which highlights a continued misunderstanding of fire dynamics within structures. The main objective of the Study of the Fire Service Training Environment: Safety, Fidelity, and Exposure is to evaluate training methods and fuel packages in several different structures commonly used across the fire service to provide and highlight considerations to increase both safety and fidelity. This report is focused on the evaluation of live-fire training in acquired structures. A full scale structure was constructed using a similar floor plan as in the research projects for horizontal ventilation, vertical ventilation, and positive pressure attack to provide a comparison between the modern fire environment and the training ground. The structure was instrumented which allowed for the quantification of fire behavior, the impact of various ventilation tactics, and provided the ability to directly compare these experiments with the previous research. Twelve full scale fire experiments were conducted within the test structure using two common training fuel packages: 1) pallets, and 2) pallets and oriented strand board (OSB). To compare the training fuels to modern furnishings, the experiments conducted were designed to replicate both fire and ventilation location as well as event timing to the previous research. Horizontal ventilation, vertical ventilation, and positive pressure attack methods were tested, examining the proximity of the vent location to the fire (near vs. far). Each ventilation configuration in this series was tested twice with one of the two training fuel loads. The quantification of the differences between modern furnishings and wood-based training fuel loads and the impact of different ventilation tactics is documented through a detailed comparison to the tactical fireground considerations from the previous research studies. The experiments were compared to identify how the type of fuel used in acquired structures impacts the safety and fidelity of live-fire training. The comparisons in this report characterized initial fire growth, the propensity for the fire to become ventilation limited, the fires response to ventilation, and peak thermal exposure to students and instructors. Comparisons examined components of both functional and physical fidelity. Video footage was used to assess the visual cues, a component of the fire environment that is often difficult to replicate in training due to fuel load restrictions. The thermal environment within the structure was compared between fuel packages with regards to the potential tenability for both students and instructors.
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Jost, Robert, Taylor Kenyon, and Scott Beason. Tahoma Creek Bridge focused condition assessment. National Park Service, 2024. http://dx.doi.org/10.36967/2303321.

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The Tahoma Creek Bridge on the southwest side of Mount Rainier is an essential crossing for year-round vehicular access to Mount Rainier National Park (MORA). This site is also exposed to significant hydrologic variability, which the current structure was not designed to withstand. Locally enhanced vertical increases to the riverbed elevation, known as aggradation, threaten the structure?s long-term viability. The purpose of this report is to (1) clarify the details of channel maintenance operations related to the bridge; (2) synthesize the natural and human influences of sediment deposition in the lower watershed; and (3) discuss the potential solutions for sustainable bridge maintenance. Information was collected through prior structural inspection reports, raw hydrologic data stored by the National Park Service, and both published and unpublished reports focused on Tahoma Creek. It was found that the height and width of the Tahoma Creek Bridge are severely underfit for relatively common flooding events on Tahoma Creek. Additionally, dredging and sediment storage practices employed to maintain the bridge are ineffective and even enhance aggradation in nominal flow conditions. Further research in the Tahoma Creek Watershed suggests the river is generally efficient at exporting produced sediments and maintains a relatively stable vertical profile in its lower reaches, where the bridge is located. The singular variation from this stable vertical trend at the bridge site suggests locally enhanced aggradation at the bridge is entirely due to the presence of the bridge itself and the channel modification actions taken to support the structure. All told, neither the overall size of the Tahoma Creek Bridge nor the channel modification actions taken to maintain the crossing, are viable for long-term access into MORA. With no changes to the existing bridge profile, the status-quo for operations to manage the Tahoma Creek Bridge will eventually fail to maintain access.
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10

Mahrt, L., and Dean Vickers. Contrasting Vertical Structures of the Stable Boundary Layer. Defense Technical Information Center, 2002. http://dx.doi.org/10.21236/ada407324.

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