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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Design method for axially loaded piled raft foundation with fully mobilised friction piles

Ayfan, Emad 16 November 2012 (has links)
In the present work, a settlement-based method is proposed to design piled raft foundation. The proposed design method is found to be very efficient, economical and requires less calculation time. Simple software can be used to execute all the interactions and loop calculations.<p>Unlike methods with numerical techniques, there are practically no limitations for the number of individual piles under the raft, size of the group and the group shape or layout. It can also be applied to piles with different length or piles that are located within multi-layered soils.<p>The raft is designed first according to the allowable settlement that is pre-defined by the structural requirements and with the necessary factor of safety. When raft suffers excessive settlement, then the load that causes excess raft settlement beyond the required limit is to be transferred to the fully mobilised frictional piles. <p>The fully mobilised shaft (with no end bearing) piles are designed with factor of safety close to unity since their function is only to reduce raft settlement and since the raft has an adequate bearing capacity.<p>Geometry of these piles is chosen to fully mobilise their shafts capacity with low settlement level in order to comply with load/settlement requirement and reduce raft settlement to the pre-defined level. <p> / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
172

Simulation numérique 3D d'Écoulement Multiphysiques Réactifs en Milieux Poreux / 3D Numerical Simulation of Multiphase flow with reactive transport in porous media

Id Moulay, Mohamed 02 December 2019 (has links)
La modélisation du transport réactif est utilisée dans de nombreuses applications énergétiques et environnementales liées aux écoulements souterrains. La modélisation de tels problèmes conduit à un système hautement non linéaire d'EDP couplées à des équations différentielles ordinaires ou algébriques. Deux types d'approches pour la résolution numérique des problèmes de transport réactif sont largement utilisés dans la littérature. L'une est l'approche de séparation des opérateurs qui consiste à découpler les problèmes d'écoulement et de transport réactif. Ces derniers sont résolus séquentiellement à chaque pas de temps. L'autre stratégie est basée sur une approche entièrement couplée dans laquelle le système entier est résolu simultanément. Le but de la thèse de doctorat est le développement d'un schéma implicite en volumes finis pour la modélisation numérique d'écoulements multicomposants monophasiques et diphasiques avec transport réactif en milieu poreux.Deux nouveaux modules de transport réactif seront implémentés dans DuMuX, un simulateur libre pour les problèmes d'écoulements et de transport dans les milieuw poreux. Des simulations numériques bi et tridimensionnels comprenant des benchmarks et du calcul haute performance, seront effectuées pour valider les modules. / Reactive transport modeling is used in many energy and environmental applications related to subsurface flows. Modeling such problems leads to a highly nonlinear system of PDEs coupled with algebraic or ODEs. Two types of approaches for the numerical solving of reactive transport problems are widely used in the literature. One is the operator-splitting approach which consists in splitting the flow and reactive transport problems. These latter are solved sequentially at each time step. The other strategy is based on the fully coupled approach in which the entire system is solved simultaneously. The goal of the PhD thesis is the development of a fully coupled fully implicit finite volume scheme for numerical modeling of single and two-phase multicomponent flows with reactive transport in porous media. New reactive transport modules will be implemented in DuMuX, a free and open-source simulator for flow and transport processes in porous media. Numerical simulations for 2D and 3D including benchmark tests and high performance computing will be performed to validate the modules.
173

Improving Network-on-Chip Performance in Multi-Core Systems

Gorgues Alonso, Miguel 10 September 2018 (has links)
La red en el chip (NoC) se han convertido en el elemento clave para la comunicación eficiente entre los núcleos dentro de los chip multiprocesador (CMP). Tanto el uso de aplicaciones paralelas en los CMPs como el incremento de la cantidad de memoria necesitada por las aplicaciones, ha impulsado que la red de comunicación gane una mayor importancia. La NoC es la encargada de transportar toda la información requerida por los núcleos. Además, el incremento en el número de núcleos en los CMPs impulsa las NoC a ser diseñadas de forma escalable, pero al mismo tiempo sin que esto afecte a las prestaciones de la red (latencia y productividad). Por tanto, el diseño de la red en el chip se convierte en crítico. Esta tesis presenta diferentes propuestas que atacan el problema de la mejora de las prestaciones de la red en tres escenarios distintos. Los tres escenarios en los que se centran nuestras propuestas son: 1) NoCs que implementan un algoritmo de encaminamiento adaptativo, 2) escenarios con necesidad de tiempos de acceso a memoria bajos y 3) sistemas con previsión de seguridad a nivel de aplicación. Las primeras propuestas se centran en el aumento de la productividad en la red utilizando algoritmos de encaminamiento adaptativos mediante un mejor uso de los recursos de la red, primera propuesta SUR, y evitando que se ramifique la congestión cuando existe tráfico intenso hacia un único destinatario, segunda propuesta EPC. La tercera y principal contribución de esta tesis se centra la problemática de reducir el tiempo de acceso a memoria. PROSA, mediante un diseño híbrido de conmutación de paquete y conmuntación de circuito, permite reducir la latencia de la red aprovechando la latencia de acceso a memoria para establecer circuitos. De esta forma cuando la información llega a la NoC, esta es servida sin retardos. Por último, la propuesta Token Based TDM se centra en el escenario con redes de interconexión seguras. En este tipo de NoC las aplicaciones esta divididas en dominios y la red debe garantizar que no existen interferencias entre los diferentes dominios para evitar de este modo la intrusión de posibles aplicaciones maliciosas. Token-based TDM permite el aislamiento de los dominios sin tener impacto en el diseño de los conmutados de la NoC. Los resultados obtenidos demuestran como estas propuestas han servido para mejorar las prestaciones de la red en los diferentes escenarios. La implementación y la simulación de las propuestas muestra como mediante el balanceado de la utilización de los recursos de la red, los CMPs con algoritmos de encaminamiento adaptativos son capaces de aumentar el tráfico soportado por la red. Además, el uso de un filtro para limitar el encaminamiento adaptativo en situaciones de congestión previene a los mensajes de la ramificación de la congestión a lo largo de la red. Por otra parte, los resultados demuestran que el uso combinado de la conmutación de paquete y conmutación de circuito reduce muy significativa de la latencia de red acceso a memoria, contribuyendo a una reducción significativa del tiempo de ejecución de la aplicación. Por último, Token-Based TDM incrementa las prestaciones de las redes TDM debido a su alta flexibilidad dado que no requiere ninguna modificación en la red para soportar una cantidad diferente de dominios mientras mejora la latencia de la red y mantiene un aislamiento perfecto entre los tráficos de las aplicaciones. / The Network on Chip (NoC) has become the key element for an efficient communication between cores within the multiprocessor chip (CMP). The use of parallel applications in CMPs and the increase in the amount of memory needed by applications have pushed the network communication to gain importance. The NoC is in charge of transporting all the data needed by the processors cores. Moreover, the increase in the number of cores pushes the NoCs to be designed in a scalable way, but at the same time, without affecting network performance (latency and productivity). Thus, network-on-chip design becomes critical. This thesis presents different proposals that attack the problem of improving the network performance in three different scenarios. The three scenarios in which our proposals are focused are: 1) NoCs with an adaptive routing algorithm, 2) scenarios with low memory access time needs, and 3) high-assurance NoCs. The first proposals focus on increasing network throughput with adaptive routing algorithms via the improvement of the network resources utilization, the first proposal SUR, and avoiding congestion spreading when an intense traffic to a single destination occurs, second proposal ECP. The third one and main contribution of this thesis focuses on the problem of reducing memory access latency. PROSA, through a hybrid circuit-packet switching architecture design, reduces the network latency by getting benefit of the memory access latency slack and to establishing circuits during that delay. In this way the information when arrives to the NoC is served without any delay. Finally, the proposal Token-Based TDM focuses on the scenario with high assurance networks on chips. In this type of NoCs the applications are divided into domains and the network must guarantee that there are no interferences between the different domains avoiding this way intrusion of possible malicious applications. Token-based TDM allows domain isolation with no design impact on NoC routers. The results show how these proposals improve the performance of the network in each different scenario. The implementation and simulations of the proposals show the efficient use of network resources in CMPs with adaptive routing algorithms which leads to an increasement of the injected traffic supported by the network. In addition, using a filter to limit the adaptivity of the routing algorithm under congested situations prevents messages from spreading the congestion along the network. On the other hand, the results show that the combined use of circuit and packet switching reduces the memory access latency significantly, contributing to a significant reduction in application execution time. Finally, Token-Based TDM increases network performance of TDM networks due to its high flexibility and efficient arbitration. Moreover, Token-Based TDM does not require any modification in the network to support a different number of domains while improving latency and keeping a strong traffic isolation from different domains. / La xarxa en el xip (NoC) s'ha convertit en un element clau per a una comunicació eficient entre els diferents nuclis dins d'un xip multiprocessador (CMP). Tant la utilització d'aplicacions paral·leles en el CMP com l'increment de la quantitat de memòria necessitada per les aplicacions, hi ha produït que la xarxa de comunicació tinga una major importància. La NoC és l'encarregada de transportar tota la informació necessària pels nuclis. A més, l'increment del nombre de nuclis dins del CMP fa que la NoC haja de ser dissenyada d'una forma escalable, sense que afecte les prestacions de la xarxa (latència i productivitat). Per tant, el disseny de la xarxa en el xip es converteix crític. Aquesta tesi presenta diferents propostes que ataquen el problema de la millora de les prestacions de la xarxa en tres escenaris distints. Els tres escenaris en els quals se centren les nostres propostes són: 1) NoCs que implementen un algoritme d'encaminament adaptatiu, 2) escenaris amb necessitat de temps baix d'accés a memòria i 3) sistemes amb previsió de seguretat en l'àmbit d'aplicació. Les primeres propostes se centren en l'augment de la productivitat en la xarxa utilitzant algoritmes d'encaminament adaptatiu mitjançant una millor utilització dels recursos de la xarxa, primera proposta SUR, i evitant que es ramifique la congestió quan existeix un trànsit intens cap a un únic destinatari, segona proposta EPC. La tercera i principal contribució d'aquesta tesi es basa en la problemàtica de reduir el temps d'accés a memòria. PROSA, mitjançant un disseny híbrid de commutació de paquet i commutació de circuit, redueix la latència de la xarxa aprofitant la latència d'accés a memòria i establint els circuits durant aquesta latència. D'aquesta forma la informació quan arriba a la NoC pot ser enviada sense cap retràs. Per últim, la proposta Token-based TDM se centra en l'escenari amb xarxes d'interconnexió d'alta seguretat. En aquest tipus de NoC les aplicacions estan dividides en dominis i la xarxa deu garantir que no existeixen interferències entre els diferents dominis per a evitar d'aquesta forma la intrusió de possibles aplicacions malicioses. Token-based TDM permet l'aïllament dels dominis sense tindre impacte en el disseny dels encaminadors de la NoC. Els resultats demostren com aquestes propostes han servit per a millorar les prestacions de la xarxa en els diferents escenaris. La seua implementació i simulació demostra com mitjançant el balancejat de la utilització dels recursos de la xarxa, els CMP amb algoritmes d'encaminament adaptatiu són capaços d'augmentar el trànsit suportat per la xarxa. A més, l'ús d'un filtre per a limitar l'adaptabilitat de l'encaminament adaptatiu en situacions de congestió permet prevenir els missatges de la congestió al llarg de la xarxa. Per altra banda, els resultats demostren que l'ús combinat de la commutació de paquet i commutació de circuit redueix molt significativament de la latència d'accés a memòria, contribuint en una reducció significativa del temps d'execució de l'aplicació. Per últim, Token-based TDM incrementa les prestacions de les xarxes TDM debut a la seua alta flexibilitat donat que no requereix cap modificació en la xarxa per a suportar una quantitat diferent de dominis mentre millora la latència de la xarxa i mantén un aïllament perfecte entre els trànsits de les aplicacions. / Gorgues Alonso, M. (2018). Improving Network-on-Chip Performance in Multi-Core Systems [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/107336 / TESIS
174

Design and fabrication of planar inductor using a fully-additive sequential build up method

Karlquist, Linus January 2021 (has links)
The miniaturization of electronics packaging is an ongoing trend. The manufacturers are increasing the packaging density to accommodate for more complex designs and increase in operating frequencies. The surface mount devices (SMDs) and today's manufacturing processes are starting to become a limiting factor to this miniaturization. The solution to these problems are embedded passives and new fully-additive manufacturing processes. In this work, a planar inductor is fabricated using a fully-additive process called Sequential Build-Up - Covalent Bonded Metallization (SBU-CBM). A new grafting material for the CBM process is tested, but found to be worse than the previously used one when tested on FR4 substrates. The best design of a planar inductor for high inductance and high Q factor is found to be the circular spiral inductor. A planar circular spiral inductor with a feature size of 75 µm is successfully fabricated using the SBU-CBM process.
175

Penzion s wellness, Brno - Soběšice / The family hotel with wellness, Brno - Soběšice

Král, Vítězslav January 2019 (has links)
This diploma thesis solves the design of a Family hotel with welness in Brno-Soběšice. The building has a T-shaped layout and has 2 above-ground storeys and one basement. The building has a flat roof with pebble. There are 12 rooms with lodging capacity of 16 guests and wellness.
176

Innovative Duplex Filter for Hydraulic Applications

Mössinger, Klaus January 2016 (has links)
For decades, duplex filters have been put to use virtually unmodified. Technologies, handling and use of materials show enormous potential for improvement. Filter element emoval/replacement is performed according to a complex process sequence. With the newly developed Duplex Filter, the market demands concerning simple filter element removal/replacement, as well as weight and pressure loss reduction are fully met.
177

Influence of the sweep angle on the leading edge vortex and its relation to the power extraction performance of a fully-passive oscillating-plate hydrokinetic turbine prototype

Lee, Waltfred 01 March 2021 (has links)
Oscillating-foil hydrokinetic turbines have gained interest over the years to extract energy from renewable sources. The influence of the sweep angle on the performance of a fully-passive oscillating-plate hydrokinetic turbine prototype was investigated experimentally in the present work. The sweep angle was introduced to promote spanwise flow along the plate in order to manipulate the leading edge vortex (LEV) and hydrodynamically optimize the performance of the turbine. In the present work, flat plates of two configurations were considered: a plate with a 6° sweep angle and an unswept plate (control), which were undergoing fully-passive pitch and heave motions in uniform inflow at the Reynolds numbers ranging from 15 000 to 30 000. The resulting kinematic parameters and the energy extraction performance were evaluated for both plates. Planar (2D) particle image velocimetry (PIV) was used to obtain patterns of the phase-averaged out-of-plane vorticity during the oscillation cycle. The circulation in the wake was then related to the induced-forces on the plate by calculating the moments of vorticity of the LEV with respect to the pitching axis of the plate. Tomographic (3D) PIV was implemented in evaluating the influence of the spanwise flow on the dynamics of the vortex structure in three-dimensional space. The rate of deformation of the vortex length was quantified by calculating the deformation terms embedded in the vorticity equations, then linked to the stability of the vortex. The results show evidence of delay of the shedding of LEV and increased vortex stability, in the case of the swept plate. The manipulation of the LEV by the spanwise flow was related to the induced kinematics exhibited by the prolonged heave forces experienced by the swept plate, which led to the higher power extraction performance at high inflow velocities. In the presence of spanwise flow, positive vortex stretching along the vortex line increased the stabilization of the vortex core and prevented the onset of helical vortex breakdown, observed in the case of the unswept plate. The use of the sweep profile on the plate has led to the improvement of energy extraction performance of the fully-passive hydrokinetic turbine. / Graduate
178

Impact of BTI Stress on RF Small Signal Parameters of FDSOI MOSFETs

Chohan, Talha, Slesazeck, Stefan, Trommer, Jens, Krause, Gernot, Bossu, Germain, Lehmann, Steffen, Mikolajick, Thomas 22 June 2022 (has links)
The growing interest in high speed and RF technologies assert for the importance of reliability characterization beyond the conventional DC methodology. In this work, the influence of bias temperature instability (BTI) stress on RF small signal parameters is shown. The correlation between degradation of DC and RF parameters is established which enables the empirical modelling of stress induced changes. Furthermore, S-Parameters characterization is demonstrated as the tool to qualitatively distinguish between HCI and BTI degradation mechanisms with the help of extracted small signal gate capacitances.
179

The effect of peripheral visual feedforward system in enhancing situation awareness and mitigating motion sickness in fully automated driving

Karjanto, Juffrizal, Md. Yusof, Nidzamuddin, Wang, Chao, Terken, Jacques, Delbressine, Frank, Rauterberg, Matthias 11 November 2020 (has links)
This study investigates the impact of peripheral visual information in alleviating motion sickness when engaging in non-driving tasks in fully automated driving. A peripheral visual feedforward system (PVFS) was designed providing information about the upcoming actions of the automated car in the periphery of the occupant’s attention. It was hypothesized that after getting the information from the PVFS, the users’ situation awareness is improved while motion sickness is prevented from developing. The PVFS was also assumed not to increase mental workload nor interrupt the performance of the non-driving tasks. The study was accomplished on an actual road using a Wizard of Oz technique deploying an instrumented car that behaved like a real fully automated car. The test rides using the current setup and methodology indicated high consistency in simulating the automated driving. Results showed that with PVFS, situation awareness was enhanced and motion sickness was lessened while mental workload was unchanged. Participants also indicated high hedonistic user experience with the PVFS. While providing peripheral information showed positive results, further study such as delivering richer information and active head movement are possibly needed.
180

Structuring of image databases for the suggestion of products for online advertising / Structuration des bases d’images pour la suggestion des produits pour la publicité en ligne

Yang, Lixuan 10 July 2017 (has links)
Le sujet de la thèse est l'extraction et la segmentation des vêtements à partir d'images en utilisant des techniques de la vision par ordinateur, de l'apprentissage par ordinateur et de la description d'image, pour la recommandation de manière non intrusive aux utilisateurs des produits similaires provenant d'une base de données de vente. Nous proposons tout d'abord un extracteur d'objets dédié à la segmentation de la robe en combinant les informations locales avec un apprentissage préalable. Un détecteur de personne localises des sites dans l'image qui est probable de contenir l'objet. Ensuite, un processus d'apprentissage intra-image en deux étapes est est développé pour séparer les pixels de l'objet de fond. L'objet est finalement segmenté en utilisant un algorithme de contour actif qui prend en compte la segmentation précédente et injecte des connaissances spécifiques sur la courbure locale dans la fonction énergie. Nous proposons ensuite un nouveau framework pour l'extraction des vêtements généraux en utilisant une procédure d'ajustement globale et locale à trois étapes. Un ensemble de modèles initialises un processus d'extraction d'objet par un alignement global du modèle, suivi d'une recherche locale en minimisant une mesure de l'inadéquation par rapport aux limites potentielles dans le voisinage. Les résultats fournis par chaque modèle sont agrégés, mesuré par un critère d'ajustement globale, pour choisir la segmentation finale. Dans notre dernier travail, nous étendons la sortie d'un réseau de neurones Fully Convolutional Network pour inférer le contexte à partir d'unités locales (superpixels). Pour ce faire, nous optimisons une fonction énergie, qui combine la structure à grande échelle de l'image avec le local structure superpixels, en recherchant dans l'espace de toutes les possibilité d'étiquetage. De plus, nous introduisons une nouvelle base de données RichPicture, constituée de 1000 images pour l'extraction de vêtements à partir d'images de mode. Les méthodes sont validées sur la base de données publiques et se comparent favorablement aux autres méthodes selon toutes les mesures de performance considérées. / The topic of the thesis is the extraction and segmentation of clothing items from still images using techniques from computer vision, machine learning and image description, in view of suggesting non intrusively to the users similar items from a database of retail products. We firstly propose a dedicated object extractor for dress segmentation by combining local information with a prior learning. A person detector is applied to localize sites in the image that are likely to contain the object. Then, an intra-image two-stage learning process is developed to roughly separate foreground pixels from the background. Finally, the object is finely segmented by employing an active contour algorithm that takes into account the previous segmentation and injects specific knowledge about local curvature in the energy function.We then propose a new framework for extracting general deformable clothing items by using a three stage global-local fitting procedure. A set of template initiates an object extraction process by a global alignment of the model, followed by a local search minimizing a measure of the misfit with respect to the potential boundaries in the neighborhood. The results provided by each template are aggregated, with a global fitting criterion, to obtain the final segmentation.In our latest work, we extend the output of a Fully Convolution Neural Network to infer context from local units(superpixels). To achieve this we optimize an energy function,that combines the large scale structure of the image with the locallow-level visual descriptions of superpixels, over the space of all possiblepixel labellings. In addition, we introduce a novel dataset called RichPicture, consisting of 1000 images for clothing extraction from fashion images.The methods are validated on the public database and compares favorably to the other methods according to all the performance measures considered.

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