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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.
321

Modélisation et analyse des transferts dans les échangeurs à plaques et ailettes à pas décalés : intensification par optimisation géométrique et génération de vorticité / Modeling and analysis of transfer in offset strip fins heat exchangers : heat transfer intensification by geometry optimization and vorticity generation

Toubiana, Ephraïm 20 January 2015 (has links)
Ce mémoire de thèse traite de l’analyse, l’intensification et l’optimisation du transfert thermique convectif dans les échangeurs à plaques et ailettes à pas décalés utilisés notamment dans le domaine automobile comme refroidisseurs d’air de suralimentation. Deux approches complémentaires sont abordées dans cette étude : des simulations numériques visant à l’analyse fine locale des caractéristiques de l’écoulement et des mécanismes de transfert, et une modélisation de type nodale permettant une caractérisation globale des performances thermo-aérauliques. Sur la gamme de Reynolds considérée différentes modélisations de la turbulence sont mises en œuvre et comparées. Ainsi des simulations aux grandes échelles (LES) permettent de qualifier des simulations de type RANS classiquement utilisées jusque-là : de fortes différences tant au niveau structuration de l’écoulement qu’au niveau performances globales sont ainsi mises en évidence selon le régime d’écoulement considéré. La mise au point d’un modèle nodal est ensuite abordée dans le but de mener des optimisations de géométries d’échangeurs non-conventionnels à pas décalés. Les différents scénarii d’optimisation considérés montrent l’intérêt de cette approche autorisant l’évaluation d’un nombre élevé de configurations géométriques. Dans une dernière partie une nouvelle géométrie innovante permettant de générer des tourbillons longitudinaux sur ce type d’ailettes est proposée et étudiée. / This thesis deals with the analysis, intensification and optimization of convective heat transfer in offset strip fins (OSF) heat exchangers used, for example, in the automotive field as water-cooled charge air coolers. Two complementary approaches are carried out in this study: CFD simulations to perform local fine analysis of the flow characteristics and transfer mechanisms, and a nodal type modeling allowing calculation of global aerothermal performance. Over the range of Reynolds numbers considered, different turbulence modeling approaches are implemented and compared: Large Eddy Simulations (LES) and RANS simulations which are usually used. The qualification of the RANS models shows that strong differences, both in the flow structure and at the overall performance evaluation level, may beobserved, depending on the flow regime considered. Then the development of a nodal model is presented. It aims at carrying out rapid optimization of geometries of unconventional OSF heat exchangers. The various optimization scenarios considered show the interest of this approach allowing the evaluation of a large number of geometric configurations. In a last part, an innovative new geometry that generates longitudinal vortices on this type of fins is proposed and studied.
322

Wellness hotel / Wellness hotel

Bambas, Vratislav January 2013 (has links)
Newly built Wellness hotel. The building is partially basement. The building has three parts. The central part is made of reinforced concrete skeleton and has five aboveground floors. This part serves as the main entrance hall and staircase. The side tracts have four aboveground floors and their support system is a transverse wall, brick, from the system Porotherm. In the basement there is a swimming pool and hotel facilities. There is located a restaurant too. On the second floor there are rooms, a gym and services. On the top floor there are only hotel rooms. The building is based on thecontinous footings. Roofing is made arched trusses.
323

Horský hotel / Mountain hotel

Ducháček, Ondřej January 2014 (has links)
This master´s thesis deals with the design of the Mountain hotel with restaurant. The project is elaborated in the form of an implanting-level documentation. The object is situated at the land parcel No.115/5 in village cald Červená voda. The object is designed as tree-storey with the partially cellarage, the roof is propose as saddle roof.
324

Penzion / Pension

Mach, Stanislav January 2015 (has links)
This thesis solves the construction of a pension that is situated on the street Vídeňská in Mikulov. It is 3-storey building and it is based on strip foundations. The roofing of the pension is solved with hipped mansard roof. The building plot is on the mildly sloping terrain, situated towards the south. Technical design solves the object, which is suitable for short accommodation in form of the pension with full board. The purpose of the use of the building is providing accommodation and restaurant services.
325

Vliv provedení zateplení objektu penzionu na výdaje spojené s provozem této nemovitosti. / Influence of insulation of a guest house on expenses related to the operation of the property

Mach, Stanislav January 2015 (has links)
The thesis solves the construction of the pension and deals with the assessment of the impact of the thermal insulation on expenses related to the operation of the property. The pension is situated on the street Valtická in Mikulov. The building has one floor and is founded on strip foundations. Roofing of the house is solved with irregular gable roof. In the first part of the thesis is a theoretical introduction mentions the possibility of building insulation and insulation methods. In the practical part of the thesis is an assessment of the heat transfer coefficient of the pension and costs associated with heating. There is also a proposal for modifications of the envelope construction with assessment of the heat factor and there are also proposed modifications to reduce the costs of operating the property.
326

Optimising benefits for rural communities in and around Protected Areas through ecotourism Public Private Partnerships (PPPs): the case of De Hoop Nature Reserve

Mnyani, Siphokazi January 2019 (has links)
Magister Artium - MA / Recent years have seen an upsurge of interest from governments and development organisations in adopting the Public Private Partnership (PPP) approach when developing and operating ecotourism projects. A PPP is a contract between a public sector institution and a private party, in which the private party assumes substantial financial, technical and operational risk in the design, financing, building and operation of a project (South African National Treasury 2004). Countries such as India, China and Kenya have developed numerous projects through PPPs. Protected Areas have followed suit in adopting the PPP approach, to be able to focus on their core business, namely conservation. To date, relevant research on PPP ecotourism projects, specifically pro-poor tourism approach is fragmented, limited in scope, and lacks examples that can assist practitioners in embedding pro-poor tourism principles in the PPP methodology. Academically, studies are largely evaluations that compare progress against projects’ defined objectives or broad based sustainable tourism goals. However, this study is an assessment of a tourism development from a pro-poor tourism perspective. Thus, this study interrogated the extent to which ecotourism PPP at De Hoop is pro-poor. Furthermore, the study sought to establish if rural local communities living in and near De Hoop PPP benefit and how their benefits can be enhanced. Pro-poor tourism indicators are used in this study as a theoretical base to evaluate De Hoop PPP.
327

Simulation numérique d'écoulements compressibles complexes par des méthodes de type Lagrange-projection : applications aux équations de Saint-Venant / Numerical simulation of complex compressible flows by Lagrange-projection type methods : applications to shallow water equations

Stauffert, Maxime 05 October 2018 (has links)
On étudie dans le cadre de la thèse une famille de schémas numériques permettant de résoudre les équations de Saint-Venant. Ces schémas utilisent une décomposition d'opérateur de type Lagrange-projection afin de séparer les ondes de gravité et les ondes de transport. Un traitement implicite du système acoustique (relié aux ondes de gravité) permet aux schémas de rester stable avec de grands pas de temps. La correction des flux de pression rend possible l'obtention d'une solution approchée précise quel que soit le régime d'écoulement vis-à-vis du nombre de Froude. Une attention toute particulière est portée sur le traitement du terme source qui permet la prise en compte de l'influence de la topographie. On obtient notamment la propriété dite équilibre permettant de conserver exactement certains états stationnaires, appelés état du "lac au repos". Des versions 1D et 2D sur maillages non-structurés de ces méthodes ont été étudiées et implémentées dans un cadre volumes finis. Enfin, une extension vers des méthodes ordres élevés Galerkin discontinue a été proposée en 1D avec des limiteurs classiques ainsi que combinée avec une boucle MOOD de limitation a posteriori. / In this thesis we study a family of numerical schemes solving the shallow water equations system. These schemes use a Lagrange-projection like splitting operator technique in order to separate the gravity waves and the transport waves. An implicit-explicit treatment of the acoustic system (linked to the gravity waves) allows the schemes to stay stable with large time step. The correction of the pressure fluxes enables the obtain of a precise approximation solution whatever the regime flow is with respect to the Froude number. A particular attention has been paid over the source term treatment which permits to take the topography into account. We especially obtain the so-called well-balanced property giving the exact conservation of some steady states, namely the "lake at rest" state. 1D and 2D versions of this methods have been studied and implemented in the finite volumes framework. Finally, a high order discontinuous Galerkin extension has been proposed in 1D with classical limiters along with a combined MOOD loop a posteriori limiting strategy.
328

Normal sväljning hos friska vuxna

Enlund, Hanna, Nyström, Linn January 2023 (has links)
Bakgrund Sväljning bedöms utifrån två aspekter - hur säker och hur effektiv den är. Tidigare studier har visat att vid stigande ålder blir sväljningen mindre effektiv och att förekomst av penetration ökar. Åldrande sväljning har i tidigare studier inte studerats specifikt utifrån säkerhet och effektivitet. Tidigare forskning med avseende på sväljning har enbart fokuserat på äldre individer respektive snävare åldersgrupper.  Syfte Aktuella studiens syfte är att undersöka om det ses en försämring i normal sväljförmåga vid stigande ålder. Studien syftar  även till att undersöka om det finns könsskillnader i hur sväljförmåga förändras vid ökande ålder, men även oavsett ålder. Bedömning av sväljfunktion, sväljningssäkerhet och sväljningseffektivitet genomfördes med Flexibel videoendoskopisk Undersökning av Sväljning (FUS).  Metod Totalt inkluderades 65 deltagare (33 st kvinnor och 32 st män), i åldrarna 21-91 år (median 44 år). FUS genomfördes för att undersöka sväljningen. Vid FUS sväljer deltagarna föda i olika konsistenser. Fynden från FUS bedömdes utifrån standardiserade skalor: The Dysphagia Outcome and Severity Scale (DOSS), Penetration-Aspiration Scale (PAS) och The Yale Pharyngeal Residue Severity Rating Scale (YPRSRS).  Resultat Majoriteten av alla deltagare bedömdes ha funktionell sväljning. Kvinnor uppvisade en bättre sväljfunktion överlag, men inga könsskillander kunde påvisas gällande säkerhet och effektivitet. Deltagare med en högre uppnådd ålder uppvisade en sämre sväljningssäkerhet och sväljningseffektivitet. Ålder kan således vara en påverkande faktor för sväljningssäkerhet och sväljningseffektivitet.   Slutsatser Denna studie visade att sväljfunktionen hos äldre deltagare var sämre än hos yngre deltagare. Sväljningens säkerhet och effektivitet var inte försämrad hos friska äldre deltagare, jämfört med friska yngre deltagare. Det fanns könsskillnader i sväljförmåga avseende sväljfunktion, kvinnor har en högre förekomst av normal sväljning än männen. Könsskillnader gällande sväljningssäkerhet kunde inte konstateras. Könsskillnad för sväljningseffektivitet kunde ses för sinus piriformis, men inte vallecula. Männen uppvisade genomgående en mindre effektiv sväljning, jämfört med kvinnorna.
329

Necessary and Sufficient Informativity Conditions for Robust Network Reconstruction Using Dynamical Structure Functions

Chetty, Vasu Nephi 03 December 2012 (has links) (PDF)
Dynamical structure functions were developed as a partial structure representation of linear time-invariant systems to be used in the reconstruction of biological networks. Dynamical structure functions contain more information about structure than a system's transfer function, while requiring less a priori information for reconstruction than the complete computational structure associated with the state space realization. Early sufficient conditions for network reconstruction with dynamical structure functions severely restricted the possible applications of the reconstruction process to networks where each input independently controls a measured state. The first contribution of this thesis is to extend the previously established sufficient conditions to incorporate both necessary and sufficient conditions for reconstruction. These new conditions allow for the reconstruction of a larger number of networks, even networks where independent control of measured states is not possible. The second contribution of this thesis is to extend the robust reconstruction algorithm to all reconstructible networks. This extension is important because it allows for the reconstruction of networks from real data, where noise is present in the measurements of the system. The third contribution of this thesis is a Matlab toolbox that implements the robust reconstruction algorithm discussed above. The Matlab toolbox takes in input-output data from simulations or real-life perturbation experiments and returns the proposed Boolean structure of the network. The final contribution of this thesis is to increase the applicability of dynamical structure functions to more than just biological networks by applying our reconstruction method to wireless communication networks. The reconstruction of wireless networks produces a dynamic interference map that can be used to improve network performance or interpret changes of link rates in terms of changes in network structure, enabling novel anomaly detection and security schemes.
330

Aggregating Form Accuracy and Percept Frequency to Optimize Rorschach Perceptual Accuracy

Horn, Sandra L. January 2015 (has links)
No description available.

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