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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.
511

Požární stanice typu C1 ve Valašském Meziříčí / Fire station class C1 in Valašské Meziříčí

Piskláková, Petra January 2018 (has links)
The diploma thesis deals with project documentation for the realization of a new fire station class C1 in Valašské Meziříčí. The building is is designet in two operating units - the garage part and the administrative part. The garage part has the necessary technical facilities and stockrooms. Over the garage there are rooms for firefighters performing the service during the night shift. The garage part follows the administrative part of the building, which has three above-ground floors. On the first floor there are offices of fire prevention, population protection and crisis management. On the second floor there are facilities for firefighters - a gym, a sauna, a day room and a classroom. The third above-ground floor is designed for the head of the territorial department, the chief of the fire station and the integrated rescue system office. The main entrance to the building is located in the administrative part of the western side at level 1NP. The structural system of the garage part consists of a prefabricated reinforced concrete frame. The administrative part is built in mansory system. The building is without cellar, roofed with flat roofs.
512

Studium chování nenewtonských kapalin ve slit-flow reometru za podmínek nestabilního toku / Studies on Non-Newtonian Behavior in Slit-flow rheometer at Unsteady flow

Halama, Lukáš January 2019 (has links)
The thesis deals with the description of the unstable flow of non-Newtonian fluid in a slit-flow rheometer, which negatively affects its behaviour. The initiators of unstable fluid flow are the roughness of the rheometer slit walls, the slip on the rheometer walls, and the influence of the inlet and outlet region geometry of the rheometer slit. The work contains methodical procedures for mathematical consideration of individual unstable fluid flow initiators and design of change of slit geometry of slit-flow rheometer. Part of the work is also a comparison of the most commonly used rheological models, derivation of general relations for the creation of the velocity profile of individual rheological models and their subsequent implementation in the rheological application, which significantly simplifies the process of evaluation of measured data when measured on slit-flow rheometer. This application can be used to determine basic parameters in CFD simulations or as a teaching aid.
513

Analýza stability svahu náchylného k sesouvání / Analysis of slope prone to sliding

Píchová, Sylvie January 2020 (has links)
The diploma thesis illustrates landslide investigation, geophysical and engineering-geological landslide survey and landslide stability reconnaissance. Static calculations based on FEM were performed in the GEO5 program. A back analysis of the landslide mathematical model was executed, which resulted in the reliability of the static landslide assessment. The complicated stabilization construction of the pile and micropile walls were optimized by mathematical modeling of successive phases of construction. The method of execution of construction work during the landslide rehabilitation was designed as well as the dimensions of reinforcing structures.
514

Návrh betonové konstrukce s ohledem na požární odolnost / Design of reinforced concrete structure with respect to fire resistance requirements

Lehoťák, Roman January 2021 (has links)
The diploma thesis deals with the analysis of internal forces and the design of the reinforcement of a reinforced concrete monolithic slab, a reinforcing wall and a column in the 1st floor of a dairy hall building. The fire resistance of selected structures was taken into account during dimensioning. The calculation of the internal forces was performed by the finite element method in Dlubal RFEM 5.24.
515

Zajistění stavební jámy na ul. Provazníkova / Design of deep excavation on the street Provaznikova

Koudelková, Ivana January 2017 (has links)
This diploma thesis describes the design and static assessment carried shoring excavation pit for the construction of a multifunctional building in Brno Husovice. Introductory part summarizes the basic input information on the area of interest, including outputs of engineering-geological survey and gives an overview of the options pits. The main part describes the design and assessment of selected variant of shoring, the subsequent evaluation of the results and the technological progress of construction. The proposed design is complemented by structural calculations and construction plans.
516

Analyse physique et simulation numérique des phénomènes de décollement de jet dans les tuyères supersoniques / Physical analysis and numerical simulation of the separation phenomenon in over-expanded nozzle flow

Piquet, Arthur 13 October 2017 (has links)
Cette thèse, initiée par un programme de coopération franco-britannique entre la DGA et la DSTL, est consacrée à l’étude des phénomènes de décollement de jet au sein des tuyères propulsives sur-détendu. L’aérothermodynamique des systèmes propulsifs (missile, avion supersonique ou lanceur) est un des domaines de la mécanique des fluides où des progrès décisifs restent à réaliser pour améliorer les performances des ensembles moteurs, en terme de bilan de poussée, de stabilité, de fiabilité et de réduction de nuisances (bruit, émission de polluants, etc.). Les conditions de vols et la complexité des phénomènes caractéristiques n’étant pas reproductibles sur bancs d’essais à l’aide des outils expérimentaux actuelles, l’utilisation de simulation numérique permettrait une étude approfondie et précise des phénomènes mis en jeu. Le besoin d’informations concernant l’instationnarité de l’écoulement s’affirmant de plus en plus, notamment sur les phénomènes basse fréquence dû aux décollements de jets, l’utilisation des simulations numériques aux grandes échelles (LES) permettrait de faire face au coût prohibitif des simulations directes (DNS). Les tuyères sur-détendu souffrent de charges latérales, caractérisées par des forces instationnaires orthogonales à la direction de l’écoulement. Ils sont causés par le décollement de la couche limite se développant le long de la paroi, provoquant des excursions de chocs importants, parfois asymétrique. Ces phénomènes instationnaires ont déjà été observés expérimentalement et numériquement. Ces instationnarités émergent d’une combinaison de phénomène complexe, tels que les interactions choc/couche limite sur la paroi de la tuyère, les couches de mélange décollées ou les zones de recirculation en aval du décollement, toutes produisant des modes énergétiques à différente fréquence caractéristique et tout particulièrement dans la plage de basse fréquence. Capturer le phénomène de décollement est un véritable défi dû à la nécessité de résoudre plusieurs échelles spatiales et temporelles. L’utilisation des simulations directes (DNS) ou résolu proche paroi (WR-LES) devient difficile compte tenu des ressources en calcul numérique actuelles. Pour parer ce problème, l’utilisation d’une stratégie de modélisation proche paroi est nécessaire. Le modèle de paroi développé par Kawai & Larsson (2013) est intégré à la simulation LES, combiné au modèle de viscosité de Duprat et al. (2011) afin de tenir compte des gradients de pression rencontré tout au long de la tuyère. Le développement d’un code curviligne a également permis de réduire le coût de calcul des simulations cylindriques en utilisant un maillage raffiné proche paroi. Les résultats obtenus à partir des simulations modélisés (WM-LES) permettent de bien mettre en évidence les phénomènes d’instationnarité menant au problème de charge latérale. Le coût de calcul étant réduit de 40 fois comparé à une simulation résolu proche paroi WR-LES, la production d’une base de donnée basse fréquence devient possible. La comparaison des calculs modélisés aux calculs résolus et aux données expérimentales confirme la bonne implémentation du modèle pour des simulations LES de tuyère propulsive. La caractérisation des différents phénomènes est faite à l’aide d’analyses spectrales effectuées sur la base de donnée permettant de mettre en avant le phénomène basse fréquence rencontré dans les tuyères sur-détendu. / The present thesis, sponsored by a Franco-British cooperation program between the DGA and the DSTL, is devoted to the study of separation phenomenon in over-expanded nozzle. The aerothermodynamic of propulsion systems (missile, supersonic aircraft or launcher) is one the fields of fluid mechanics where important progress remains to be made in order to improve the performance of the engine, in terms of thrust, stability, reliability and pollutant (noise reduction, pollutant emissions, etc.). Since the flight conditions and the complexity of the characteristic phenomena are not reproducible on experimental benches, the use of numerical simulation would allow a thorough and precise study of the phenomena involved. The instationnarity observed in the separation of the boundary layer is becoming a main concern nowadays, especially the low-frequency phenomenon observed in some experiments, the use of large scale simulations (LES) would fit perfectly the computational power allocated on supercomputer compared to the prohibitive cost of direct simulations (DNS). Over-expanded nozzles are known to suffer from side loads, characterized by undesired unsteady forces orthogonal to the flow direction. They are caused by boundary-layer separation that causes significant and asymmetrical shock excursions within the nozzle. These phenomena have been studied experimentally and numerically. They emerge from a combination of complex unsteady flow phenomena, not yet fully understood, such as shock/boundary-layer interactions at the nozzle walls, detached mixing layers, and large regions of recirculating flow, all producing energetic motions at frequencies one or two orders of magnitudes lower than the characteristic frequency of the incoming turbulence. Capturing the phenomenon is a real challenge due to the need to resolve at least four decades of time scales, from the energetic scales of the incoming turbulence. This makes both direct (DNS) and wall-resolved large-eddy simulations (WR-LES) rather impractical. Instead, a wall-modelled LES (WM-LES) strategy is employed here, following the approach of Kawai & Larsson (2013) together with the eddy-viscosity modification of Duprat et al. (2011) so as to account for pressure gradients. The WM-LES is found to accurately reproduce the flow topology, as well as the spectral content obtained by a reference WR-LES. The development of a curvilinear code has allowed us to decrease the cost of computation of the simulations by using a stretched mesh close to the wall. The results obtained from the wall-modeled simulations (WM-LES) allowed us to capture and study the phenomena of instationnarity leading to the problem of side-loads. The WM-LES being about 40 times cheaper, the low-frequency motions may be statistically converged, enabling the study of the very low frequencies. The comparison of the modeled simulations with the resolved simulations and the experimental data confirms the good implementation of the model for LES computations of over-expanded nozzle flow. The characterization of the different phenomena is done through spectral analyses, carried out on the LES database allowing the highlight of the low-frequency phenomenon encountered in the over-expanded nozzle flow.
517

Projektering av odlingsvägg för inomhusbruk som bevattnas med uppsamlad nederbörd från byggnadens tak / Designing an interior wall for cultivation that is irrigated with pre-stored precipitation from the building's roof

Elsebti, Isabella, Ljungdal, Ida January 2013 (has links)
I takt med att klimathoten mot vår planet ökar raskt, ökar också människors egna engagemang för att lösa problematiken. I städerna finns det initiativ med målsättningen att skapa en bättre framtid för jorden än den som idag spås. Problem med överbelastade dagvattensystem och långa mattransporter i städerna är två klimathot som bl.a. kan avhjälpas med lokalt omhändertagande av dagvatten respektive stadsodling. Därför kommer följande rapport att avhandla hur det på bästa sätt kan utformas en odlingsvägg inomhus som tar hand om nederbördsvatten från byggnadens tak i projektet Haningeterrassen. För att lösa uppgiften har litteraturstudie, studiebesök och intervjuer varit underlag för arbetet som även har innehållit en fallstudie. Detta för att få en bättre inblick i hur hela väggen och systemet bör utformas för en specifik byggnad, i vårt fall ett hus i projektet Haningeterrassen. Målet med projekt har varit att ta fram ett förslag på en byggteknisk lösning på en grön vägg inomhus som kan hantera nederbörd m.h.a. planterade nyttoväxter exempelvis sallad, tomat och basilika. Där följande frågor har besvarats för den utvalda byggnaden i Haningeterrassen: Hur kan en grön vägg bli ett verktyg för människor att använda som en del i den hållbara staden? Hur utformas en grön vägg som bevattnas med nederbörden från byggnadens tak? Nyttoväxterna bidrar till stadens hållbara utveckling genom att minska mattransporter till staden för väggens brukare. Och utnyttjandet av nederbörd bidrar till stadens hållbara utveckling genom att minska belastningen på stadens dagvattensystem. Viktigt att poängtera är att denna vägg enbart är en förslagsskiss och en fortsättning på projektet är önskvärd. / Whilst the climate threat on earth increases, people’s own involvement in the issue increases with it. Several initiatives exist in the cities with the objective to create a better future for the earth than what is predicted today. Problems with overburdened stormwater systems and long transport distances for food are two of these climate threats that can be decreased with local management of stormwater respectively urban farming. Therefore the following report will examine the preferable way to create an interior wall for cultivation that is irrigated with pre-stored precipitation from the roof of a specific building in the project Haningeterrassen. For solving the task, literature studies, study visits and interviews have been the foundation for the work, which also have included a case study. This to get a better insight in how the whole system and a green wall should be designed for a specific building, in our case a house in the project Haningeterrassen. The goal with the project has been to form a proposal of a design solution of a green inner wall that can manage precipitation with planted culturing plants for example lettuce, tomato and basil. The following questions have been answered for the chosen building in Haningeterrassen: How can a green wall become a tool for the average person to use as a part of the sustainable city? How is a green wall best designed for managing the precipitation that lands on its building’s roof by being irrigated with it?  The culturing plants in the wall contribute to the city’s sustainable development by reducing long transport distances for food for the users of the wall. And the usage of precipitation contributes to the city’s sustainable development by reducing the burden on the city’s stormwater systems. It is important to acknowledge that this green wall only is a proposal sketch. A continuation of the project is desirable.
518

Beräkningsmall för väggskivor enligt Eurokoder

Sharif, Samereh, Javaherian, Mahmoud Reza January 2011 (has links)
The regulatory framework for constructional calculations in Sweden did expire In January the 1.st, 2011.Since then the constructional regulatory that originally were composed by Boverket (BKR) has been replaced by new common range (Eurocodes) for the entire European Union. This transition has led to changes in existing rules and standards regarding dimensioning area in Grids and has forced a need for updating to structural Engineers. The new calculation system has caused time-consuming studies of the new rules and a proper understanding of all the advice and regulations for the entire profession. This study has been carried out in cooperation with the firm "Knut Jönson Ingenjörs AB i Stockholm”, that has been affected by this transition as all other consulting firms. The firm has requested for a calculation method of wall beams according to Eurocodes. The study's focus is therefore to clarify the rules and guidelines regarding the design of wall beams according to the new regulation. The calculation model describes step by step how the dimensioning has been carried out. The result indicates the amount of reinforcement, required for s a solid construction. Two different cases has been reviewed regarding reinforcement arrangement .In one case calculates the amount of reinforcement in the joist meanwhile in the other case calculate the reinforcement in the wall. To comprehend the process of dimensioning according to those different norms compares theirs calculations. Illustration of both of those calculations according to their norm has been enclosed as appendix 1-2 in the report. An Excel program has been elaborated for dimensioning of wall beams according to EK3. The firm's existing Excel-page according to BBK 044 has been applied as basis. The difference in those two dimensioning methods has been analyzed with consideration to obtained results of calculation illustration. In the analyze appears the result based on those two cases of reinforcement arrangements. It shows that tension condition in frameworks model is runes by core details and board’s height. The differences in these two calculation methods were fractional. It seems difficult to decide which method provides a more secure result but Ek seems to be more substantial. / Regelsystemet för konstruktionsberäkningar i Sverige har upphört att gälla från och med den första januari 2011. Boverkets konstruktionsregler (BKR) har därmed ersatts av ett nytt gemensamt regelsystem (Eurokoder) för hela Europa unionen. Övergången har medfört förändringar gällande både regler och normer vid dimensionering av bärverk . Dessa förändringar har mest påtvingat byggnadskonstruktörer att uppdateras. Det nya beräkningssystemet har orsakat tidskrävande studier av de nya reglerna samt en korrekt uppfattning av alla råd och föreskrifter för alla konstruktörer. Detta arbete har genomförts i samarbete med företaget Knut Jönson Ingenjörs AB i Stockholm vilket är ett bland de alla konsultföretag som har påverkats av denna övergång . Företaget har önskat sig en beräkningsgång för väggskivor enligt Eurokoder. Rapportens tyngdpunkt ligger därför i att tydliggöra vilka regler samt anvisningar gäller vid dimensionering av väggskivor enligt den nya normen. Beräkningsmallen redogör stegvis om hur dimensioneringen genomförs. Resultatet anger armeringsmängd som erfordras för att konstruktionen ska få tillräcklig hållfasthet. Två olika fall har betraktats när det gäller anordning av armeringar. I det ena fallet beräknas armeringsmängden med anordning av armering inom en anslutande bjälklagstjocklek medan i det andra fallet utförs beräkningar med anordning av armeringar inom väggtjockleken. För att få en ingående förståelse av dimensioneringsprocessen enligt de olika normerna har en beräkningsjämförelse utförts. Beräkningsexemplet enligt både normerna är bifogad som bilaga 1-2 i rapporten. Ett Excel-blad har även utvecklats för dimensionering av väggskivor enligt EK 1. Företagets befintliga Excel-blad enligt BBK 042har tillämpats som underlag. 1 Eurokoder Skillnaden mellan de två dimensioneringsmetoderna har analyserats med hänsyn till erhållna resultat från beräkningsexemplet. I analysen framgår resultatet utifrån beräkningsexemplet för de två fall av armeringsanordningar. Det har visat sig att spänningstillståndet i fackverksmodellen styrs av upplagsdetaljer samt skivans höjd. Skillnaden mellan de två olika beräkningsmetoderna var marginella. Det är väldigt svårt att avgöra om vilken metod ger ett säkrare resultat men EK uppfattas som en mer omfattande metod .
519

Advancing understanding of secondary cell wall polymer binding and synthesis in S-layers of Gram-Positive bacteria

Legg, Max 21 April 2022 (has links)
Self-assembling protein surface layers (S-layers) are ubiquitous prokaryotic cell-surface structures involved in structural maintenance, nutrient diffusion, host adhesion, virulence, and many additional processes, which makes them appealing targets for therapeutics and biotechnological applications, including live vaccines, liposome drug delivery and biosensors. Unlocking this potential requires expanding our understanding of S-layer properties, especially the details of surface-attachment. S-layers of Gram-positive bacteria often are attached through the interaction of specialized S-layer homology (SLH) domain trimers with peptidoglycan-linked secondary cell wall polymers (SCWPs). Characterization of this interaction in the Gram-positive model organism Paenibacillus alvei CCM 2051T reveals that, remarkably, binding-site switches can occur between two distinct SLH-domain SCWP receptor-site grooves in the S-layer protein SpaA, possibly as part of a mechanism to alleviate strain in the S-layer. To date, however, analysis of this novel mechanism has been limited to the terminal SCWP monosaccharide and the internal SCWP repeat disaccharide ligand analogues, leaving open the role of subsequent SCWP sugar residues in binding, as well as whether the two receptor sites are also suited to accommodate longer SCWP ligands that better approximate the biological target at the surface of P. alvei. To address this, the objective of this work aims to uncover and characterize the details of the SpaA SLH-domain (SpaASLH¬) SCWP-interaction by determining the co-crystal structures of SpaASLH¬, and single (SpaASLH/G109A) and the corresponding double (SpaASLH/G46A/G109A) mutants in complex with synthetic terminal disaccharide and trisaccharide analogues of the P. alvei CCM 2051T SCWP target. These structural characterizations have been supplemented with disaccharide and trisaccharide binding data, which was obtained through thermodynamic ITC analyses carried out by collaborators. The co-crystal structures of P. alvei SpaASLH with synthetic, terminal SCWP disaccharide and trisaccharide analogues, together with previously published monosaccharide-bound SpaASLH structures, reveal that while the SLH trimer accommodates longer biologically relevant SCWP ligands within both its primary (G2) and secondary (G1) binding sites, the terminal pyruvylated ManNAc moiety serves as the nearly-exclusive SCWP anchoring point. Binding is accompanied by displacement of a flexible loop adjacent to the receptor site that enhances the complementarity between protein and ligand, including electrostatic complementarity with the terminal pyruvate moiety. Remarkably, binding of the pyruvylated monosaccharide SCWP fragment alone is sufficient to cause rearrangement of the receptor binding sites in a manner necessary to accommodate longer SCWP fragments. The observation of multiple conformations for longer oligosaccharides bound to the protein, together with the demonstrated functionality of two of the three SCWP receptor binding sites, reveals how the SpaASLH-SCWP interaction has evolved to accommodate longer SCWP ligands and alleviate the strain inherent to bacterial S-layer adhesion during growth and division. In addition, to further clarify the steps involved in SCWP biosynthesis, we present a crystal structure of the unliganded UDP-GlcNAc 2-epimerase enzyme MnaA, which catalyzes the interconversion of UDP-GlcNAc into UDP-ManNAc—an essential building block of the P. alvei SCWP target. The P. alvei MnaA epimerase adopts a GT-B fold that is consistent with the architecture of previously published structures of other bacterial non-hydrolyzing UDP-GlcNAc 2-epimerase enzymes for which substrate binding is observed in the cleft located between the two domains. Characterization of this structure, coupled with an analysis of the sequence of the MnaA protein, reveals the presence of conserved residues that define the catalytic and allosteric sites in homologous enzymes from different organisms. These residues are positioned to accommodate substrate within the MnaA binding cleft in much the same manner as the published enzyme homologues, suggesting that allosteric regulation as a mechanism for enzyme regulation is conserved in P. alvei MnaA. These investigations are part of a greater effort toward understanding SLH domain-mediated SCWP-interactions in Gram-positive organisms, and provide insight into the structure and putative function of this SCWP biosynthetic enzyme. By understanding these processes, this knowledge may contribute to providing a platform for the rational design of Gram-positive inhibitors. Such inhibitors could selectively target, for example, the bacterial S-layer SCWP-binding interaction, or perhaps the essential biosynthetic enzymes involved in producing the exclusive targets that these S-layer proteins recognize and bind, and would thus represent a new class of antimicrobial therapeutics. / Graduate
520

The Wall Still Stands... Or Does It? Collective Memory of the Berlin Wall as Represented in American and German Newspapers

Hiller, Katlin M. 01 October 2018 (has links)
No description available.

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