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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.
91

Complexes de type Morse et leurs équivalences

Morin, Audrey 04 1900 (has links)
L'obtention de ce mémoire a été rendue possible par le soutien financier du FRQNT et du CRSNG. / Ce mémoire est une étude détaillée de certains aspects de la théorie de Morse et des complexes de chaînes qui en découlent : le complexe de Morse, le complexe de Milnor et le complexe de Barraud-Cornea. À l’aide de différentes techniques de la topologie différentielle et de la théorie de Morse, dont les bases forment les premiers chapitres de ce texte, nous ferons la construction détaillée de ces trois complexes avant de démontrer leurs équivalences deux à deux. Ce mémoire synthétise et met en parallèle trois branches de la théorie de Morse en ne supposant que des connaissances du niveau d’un étudiant de début maîtrise. / In this thesis, we study aspects of Morse theory and the chain complexes that derive from it : the Morse complex, the Milnor complex and the Barraud-Cornea complex. Using different techniques from differential topology and Morse theory, which will be presented in the first chapters, we carefully build these complexes before proving their equivalence. This thesis synthesises and compares three points of view in Morse theory in a document accessible to beginning graduate students.
92

Modifikace tříválcového vznětového motoru na zkušební jednoválec / Modification of a three-cylinder diesel engine to a single cylinder test engine

Rejnuš, Miroslav January 2021 (has links)
The master thesis deals with the design of a single-cylinder diesel piston internal combustion test engine by modifying the initial mass-produced three-cylinder engine. The first part of the thesis is devoted to the introduction to the problems of diesel and experimental single cylinder engines. Subsequent chapters focus on the adaptation of the baseline engine itself, including balancing of inertial forces. Furthermore, the crankshaft operability is checked, including the determination of safety against high-cycle fatigue. The last chapter deals with the design of the connection of the adapted unit to the dynamometer.
93

Hnací mechanismus Stirlingova motoru / Crankshaft mechanism of Stirling engine

Valčík, Martin January 2018 (has links)
This diploma thesis is focused on the design of the driving mechanism of Stirling engine, where was chosen modification of these engines with rhombic drive. Subsequently is constructed kinematical, dynamical and thermomechanical mathematical model. Finally, is going from these models for execution strength control and drawing documentation.
94

Zážehový pětiválcový hvězdicový letecký motor / Petrol five-cylinder radial aircraft engine

Donutil, Jan January 2019 (has links)
This thesis deals with configuration of radial five-cylinder engine with attention to crank mechanism. Covered topics are motion of crank mechanism with articulated connecting rod, force analysis and balancing of inertial forces. The second part discusses FEM analysis and calculation of safety factor of selected component.
95

Sportovní centrum TJ Slavoj Jeseník nad Odrou / The Sports Centr TJ Slavoj Jeseník nad Odrou

Lušovský, Lukáš January 2020 (has links)
The subject of this diploma thesis is an extension of a two-storey basement sports center in Jeseník nad Odrou. There is a relaxation area and a fitness area in the sports center. It is connected to the existing gym building with the tourist hostel by means of a connecting neck. There is a reception and a café for both facilities. The whole building is then covered with single-layer flat roofs. The main entrance to the building is located on the southeast side of the building at level 1.NP. Vertical constructions are made mainly of ceramic sys-tem elements Porotherm. Ceiling constructions are designed as prefabricated prestressed panels. The staircases are prefabricated reinforced concrete. The project was developed using the computer program AutoCAD.
96

Numerický model uspořádání dutých vláken v tepelném výměníku / Numerical model of hollow fiber arrangement in heat exchanger

Cabalová, Klára January 2020 (has links)
This paper deals with the topic of numerical arrangement of fibers in a heat exchanger. The heat exchanger is scanned in an industrial tomograph and the acquired data are represented by the field of voxels. The method used in this paper is based on tracing the fiber fragments through the use of image analysis and the subsequent numerical connection of the fragments. The result is a set of fibers that are represented by points in the field through which they are passing.
97

Připojování fotovoltaických zdrojů k distribuční síti / Connecting of the Photovoltaic Power Sources to the Distibution Network

Ondroušek, Luděk January 2009 (has links)
This work is focused on the current issues, which are associated with the connection of fotovoltaic sources to the distribution grids. An example of these problems can be the connection of the bigger fotovoltaic power plant to the part of the grid with small short-circuit power. In consequence of this, it can happen that the quality parameters (voltage) of this grid are undesiderably influenced. Integral part of the connection procedure of the new sources to the grid is also a design and method of the power output, which is also part of this work.
98

Zastřešení planetária / The roof structure of the planetarium.

Vojta, Radek January 2017 (has links)
The aim of the final thesis was to design and assess timber loadbearing structure of planetarium located in Brno and height of the construction 10 m. Designed building of planetarium consists of dome and hall, which operate separately. The structure is designed from glue laminated timber, solid timber and steel bracing, ridge ring and connecting elements. Building foundations is solved by reinforced anchor blocks fixed to foundation pads, which are connected by foundation strips. Loadbearing structure of the dome consists of arched beams together with purlins and ridge ring. Stability is ensured by 4 fields of cross bracing located between purlins. Loadbearing structure of the hall consists of roof and wall beams connected by frame corners together with roof and wall purlins. In gable walls is structure complemented by columns. Stability is ensured by diagonal and vertical elements situated between wall purlins, which together form a truss system.
99

Automated Construction- Reinforcement : Lifting Prefabricated Reinforcement Cages / Automatiserad Konstruktion-Armering

Pettersson, Markus, Larsson, Andreas January 2021 (has links)
The construction industry is moving towards an increasingly industrial production and one step towards this is to use prefabricated rebar cages. A new concept is being tested where tied rebar cages are produced on the construction site by industrial robots. The industrial robots produce the rebar cages based on a geometric model and when finished they are lifted to the casting site with the help of a crane. In order for this concept to become an efficient process, it must already be possible to evaluate the stability of the rebar cages in the early design phase to be able to efficiently determine whether it is possible to lift the rebar cages to the casting site after production. The scope of this thesis is to investigate what is required to create a numerical model with help of data from a geometric model in an efficient way in order to determine whether a rebar cage can be lifted. This thesis is limited to one specific rebar cage that has already been created in the CADprogram Tekla Structures by the contractor Skanska Sweden AB. The process of what is required when creating a numerical model with data from a geometric model is limited between the analysis software LUSAS Bridge and the CAD software Tekla Structures. To be able to determine what is required in order to create a numerical model with data from a geometric model in the analysis software LUSAS Bridge in an efficient way a survey was performed. The survey includes the necessary steps to create a numerical model of a tied rebar cage from a geometric model and the problems that occurs along the way to get an efficient process. In order to determine if the geometric model of the rebar cage is liftable a linear analysis was created in the analysis software LUSAS Bridge. The analysis was created with data from the geometric model created in Tekla Structures and with experimental results from a study where tied connection strength and stiffness were evaluated. The analysis was created to simulate a rebar cage for a bridge foundation in scale 1:2 that is lifted in four lifting points. The lifting points in this analysis is modeled as supports while the rebar cage is subjected to an acceleration force to simulate a lift. The analysis is performed in two parts, first when the tied connections have full stiffness capacity and the second part when the stiffness is decreased to be able to evaluate what happens to the stability of the rebar cage. In order to determine if the rebar cage is liftable two conditions are looked at, (1) stress in rebars and (2) forces in the joint elements. The results from the study show that in order to create a numerical model of a tied rebar cage in an efficient way some improvements must be done in the analysis software LUSAS Bridge. The most time-consuming process when creating a numerical model of a tied rebar cage are the connections. In order to create these tied connections in an efficient way some new functions must be created in LUSAS Bridge where the software can generate different types of tied connections. The results from the analysis show that the stress in the rebars at the lifting points is the criterion that is most critical when the rebar cage is lifted. The maximum stress reached 356 MPa with the utilization rate of 81,9% when the connection stiffness has full capacity. When the connection stiffness was adjusted, it was also shown here that the stress was the criterion that is most critical. The analysis for 50% connection stiffness capacity showed a maximum stress of 402 MPa with the utilization rate of 92,4%, this shows an increase of 10,5% of the utilization rate when the IV  connection stiffness is decreased with 50%. Based on these results, it can be stated that the rebar cage can be lifted if four lifting points are used. It can also be seen from the results that the stiffness in the connections has a very small impact on the behavior of the cage and therefore the placement of the rebars contributes more to the stability. / Byggindustrin går mot ett allt mer industriellt byggande och ett steg på vägen är att använda sig av prefabricerade armeringskorgar. Ett nytt koncept håller på att undersökas där man vill framställa najade armeringskorgar på byggarbetsplatsen med hjälp av industrirobotar. Industrirobotarna bygger armeringskorgarna utifrån en geometrisk modell för att sedan lyftas till gjutplatsen med hjälp av en kran. För att detta koncept ska bli en effektiv process måste man redan i projekteringsfasen kunna utvärdera armeringskorgarnas lyftbarhet för att kunna avgöra om det går att lyfta armeringskorgarna till gjutplatsen efter att de är färdigmonterade. Examensarbetets syfte är att undersöka vad som krävs för att ska skapa en numerisk modell med hjälp av data från en geometrisk modell på ett effektivt sätt för att sedan kunna avgöra om en armeringskorg går att lyfta. Denna studie är avgränsad till enbart en typ av armeringskorg som redan är skapad i CADprogrammet Tekla Structures av entreprenören Skanska Sverige AB. Processen som krävs för att skapa en numerisk modell med hjälp av en geometrisk modell är begränsad till analysprogrammet LUSAS Bridge och CAD-programmet Tekla Structures. För att kunna avgöra vad som krävs för att skapa en numerisk modell med hjälp av en geometrisk modell i analysprogrammet LUSAS Bridge utfördes en kartläggning. Kartläggningen omfattar de steg som krävs för att skapa en numerisk modell av en najad armeringskorg från en geometrisk modell och de svårigheter som finns längs vägen. För att kunna avgöra om den geometriska modellen av armeringskorgen är lyftbar skapades en linjär Finita Element Analys i analysprogrammet LUSAS Bridge. Analysen är skapad med hjälp av data från den geometriska modellen från Tekla Structures samt testresultat från en tidigare studie där man har provat hållfastheten och styvheten hos najade knutpunkter. Analysen är skapad för att efterlikna en armeringskorg till ett brofundament i skala 1:2 som lyfts i fyra punkter. Lyftpunkterna i denna analys är simulerade som stöd medan armeringskorgen utsätts för en accelerationskraft för att efterlikna ett lyft. Analysen utförs i två delar, en när de najade knutpunkterna har full styvhet och den andra när styvhet för knutpunkterna minskar. Detta för att se hur styvheten i knutpunkterna påverkar stabiliteten i armeringskorgen. Armeringskorgens lyftbarhet bedöms av två olika kriterier (1) spänning i armeringsjärnen och (2) krafter i knutpunkterna. Resultaten från studien visar att för att kunna skapa en numeriskmodell av en najad armeringskorg på ett effektivt sätt måste en del förbättringar göras i analysprogrammet LUSAS Bridge. Den process som är mest tidskrävande är när man skapar de najade knutpunkterna för armeringskorgen. För att det ska gå att genomföra detta på ett effektivt sätt måste en ny funktion skapas i LUSAS Bridge där programmet kan generera olika typer av knutpunkter automatiskt. Resultaten från analysen visade att spänningen av armeringsjärnen vid lyftpunkterna är det kriterium som är mest kritisk när armeringskorgen utsätts för lyft. Den maximala spänningen uppgick till 356 MPa med en utnyttjandegrad på 81,9% för armeringskorgen med full styvhet. När styvheten justerades visades det även här att spänningen är det kriterium som är mest kritiskt. Analysen för 50% styvhet visade en maximal spänning på 402 MPa med en utnyttjande grad på 92,4%, detta visar en ökning på 10,5% av utnyttjandegraden när styvheten halveras. VI  Utifrån dessa resultat kan man konstatera att armeringskorgen går att lyfta om man använder fyra lyftpunkter. Man kan även utifrån resultaten se att en minskning av styvheten i knutpunkterna har en liten påverkar på armeringskorgens lyftbarhet och istället är det placeringen av armeringsjärnen som har störst betydelse.
100

Úprava MÚK silnic R46 a II/428 u Vyškova / Design of interchange R46 and II/428 near Vyškov

Běloušek, Ondřej January 2012 (has links)
This thesis solves design of intrchange R 46 and II/428 near Vyškov, more exactly specified in the village Drysice. In the existing situation is not resolved connecting lanes and turning lanes at the interchange. This causes reduced road safety, which leads to a significant number of traffic accidents in this section. The thesis solves design respectively modification substandard connecting and turning lanes on all parts of flyover crossroads with associated modifications of two bridges. Integral part of the proposed modification is the elimination of existing noise load in the village, by using of noise barriers.

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