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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.
311

Panelový měřicí přístroj / Panel meassurement device

Vaško, Pavel January 2011 (has links)
The master thesis includes a literature search, which is focused on questions around panel measure instruments for measuring analog voltage signals. There is the block diagram and the concept of measuring voltage values designed from collected information and defined requirements to the device. In the next step a design of the circuit diagram is created and published and consequently transferred into PCB. The whole board has been fabricated, assembled and tested. The firmware development starts with the definition of basic functional blocks for using of internal elements of the device, which is followed by the implementation of the Modbus slave station service routine. The top part presents graphical user interface on the device.
312

Simulace ukazatelů spolehlivosti městské distribuční sítě 22kV pro různé konfigurace vývodů / Simulation of reliability indices of a 22kV urban distribution network with various outgoing feeder configurations

Semerád, Jiří January 2011 (has links)
This work deals with simulation of the urban distribution network reliability. For the evaluation of these networks are used indicators of reliability which are described in the first part. Next methods of analysis and posibilities for capabilities reliability simulation of distribution network are described. The third part deals with the real value of the reliability of electricity distribution in Italy. These values are presented in tables and graphs. The last part is a simulation of the urban network. Effect of different configurations on the reliability of electricity supply are studied. Sensitivity analysis is done for failure rate and proportional of the number of sampling points; the simulated values are fiven in tables and graphically.
313

Návrh modelu prádelny budoucnosti / Design of up-to-date laundry premise model

Marek, Tomáš January 2010 (has links)
Scope of this thesis is the design and evaluation of a laundry processing facility. Main goal was to prepare, design and evaluate part of the technological layout for a modern, high-volume laundry processing facility. The focus was on the main apparatuses, main process flow, as well as the supporting process flow, related equipment and key components of field instrumentation with standard description. 3D facility model was prepared on the basis of proposed technological layout, using the SolidWorks software package. This model shows placement of all key equipment and components as well as physical disposition of connection tubing within the building. Final part of work reviews proposed options of process parameters measurement. Such measurements which are important for the evaluation of energy consumption of considered laundry processing. We discuss both pros and cons of evaluated and selected suitable measurement devices, tools and procedures. Constructed 3D model of piping lines shows placing and dimensions of selected measurement devices.
314

Retrofit parní turbiny 250 MW na biomasu / Biomass Retrofit 250 MW Steam Turbine

Novák, Martin January 2013 (has links)
There is a description of modernisation steam condensing turbine in this Master´s thesis. Electric output is decreased from 250 MW to 160 MW. This thesis is divided into two parts, there is a calculation of heat balance in first part and a calculation of blading in second part. Detail drawing and heat balance are the most important results of this Master´s thesis.
315

Kondenzační parní turbina s přihříváním / Condensing Steam Turbine with superheating

Urbánek, Martin January 2014 (has links)
The thesis is focused on designing of condensing steam turbine with reheating for combustion of biomass. The turbine is developed to be tandem compound-regenerative with five uncontrolled extraction points. Optimization of reheating pressure is made in the turbine's cycle. The turbine outlet is constructed to lead down to the water cooled condenser. Thesis includes the calculation of heat cycle with the draft of flow channel of high pressure and middle-low pressure turbine. Detailed calculation of middle-low pressure turbine, including stress-strength analysis, is performed. The thesis provides an evaluation of flow scheme of 100 % and 75 % of generator’s power output and the drawing of middle-low pressure turbine in longitudinal section.
316

Kondenzační parní turbina / Condensing Steam Turbine

Žáček, Ondřej January 2015 (has links)
The aim of the thesis „Condensing steam turbine“ is design of condensing steam turbine with uncontrolled extractions. The design is made according to assigned parameters. Balancing scheme of the turbine is defined at the beginning of the thesis. Then design of the regulation stage and reaction stages is accomplished. The calculation (thermodynamic and strength) is computed for mentioned two parts. For thermodynamic calculation is used ca/u method. In closing the design of the seal system is made.
317

Segmentovaná diskrétní waveletová transformace / Segmentwise Discrete Wavelet Transform

Průša, Zdeněk January 2012 (has links)
Dizertační práce se zabývá algoritmy SegDWT pro segmentový výpočet Diskrétní Waveletové Transformace – DWT jedno i vícedimenzionálních dat. Segmentovým výpočtem se rozumí způsob výpočtu waveletové analýzy a syntézy po nezávislých segmentech (blocích) s určitým překryvem tak, že nevznikají blokové artefakty. Analyzující část algoritmu pracuje na principu odstranění přesahu a produkuje vždy část waveletových koeficientů z waveletové transformace celého signálu, které mohou být následně libovolně zpracovány a podrobeny zpětné transformaci. Rekonstruované segmenty jsou pak skládány podle principu přičtení přesahu. Algoritmus SegDWT, ze kterého tato práce vychází, není v současné podobně přímo použitelný pro vícerozměrné signály. Tato práce obsahuje několik jeho modifikací a následné zobecnění pro vícerozměrné signály pomocí principu separability. Kromě toho je v práci představen algoritmus SegLWT, který myšlenku SegDWT přenáší na výpočet waveletové transformace pomocí nekauzálních struktur filtrů typu lifting.
318

Kondenzační parní turbína / Condensing Steam Turbine

Šrůtek, Petr January 2016 (has links)
The theme of master's thesis is the design of condensing steam turbine with three unregulated steam outputs. The steam parameters in individual outputs are dealt with in heat balance circulation. This chapter is followed by thermodynamic and strength calculations, including the calculation of the turbine gland steam and design of drainage. Structural design of the turbine is also included in this thesis.
319

Jádra schématu lifting pro vlnkovou transformaci / Lifting Scheme Cores for Wavelet Transform

Bařina, David Unknown Date (has links)
Práce se zaměřuje na efektivní výpočet dvourozměrné diskrétní vlnkové transformace. Současné metody jsou v práci rozšířeny v několika směrech a to tak, aby spočetly tuto transformaci v jediném průchodu, a to případně víceúrovňově, použitím kompaktního jádra. Tohle jádro dále může být vhodně přeorganizováno za účelem minimalizace užití některých prostředků. Představený přístup krásně zapadá do běžně používaných rozšíření SIMD, využívá hierarchii cache pamětí moderních procesorů a je vhodný k paralelnímu výpočtu. Prezentovaný přístup je nakonec začleněn do kompresního řetězce formátu JPEG 2000, ve kterém se ukázal být zásadně rychlejší než široce používané implementace.
320

Modélisation des écoulements réactifs dans les microsystèmes énergétiques / Modelling of the reactive flows in energetic micro systems

Ngomo Otogo, Davy Kévin 16 November 2010 (has links)
La miniaturisation de plus en plus poussée (micro et nano) des systèmes mécanique connaît un important développement depuis une dizaine d'années. Leur conception et réalisation nécessite une connaissance approfondie des écoulements micro-fluidiques. Dans le domaine énergétique, le rendement d'un moteur thermique se dégrade sérieusement lors d'une réduction d'échelle. En effet, les pertes de chaleur pariétales peuvent devenir aussi importantes que l'énergie libérée. Une voie prometteuse consiste à utiliser les ondes de choc / détonation pour accélérer la libération d'énergie. Dans ce cas, la détonation peut être assimilée à une onde de choc inerte, couplée à une zone de réaction, caractérisée par la présence d'instabilités longitudinales et transverses, soumettant ainsi le front de choc à de violentes accélérations / décélérations. L'objectif de la thèse est de mieux appréhender la structure moyenne de la zone de réaction qui s'étend du choc jusqu'à la surface sonique. Sur le plan de la modélisation numérique, les équations de Navier-Stokes compressibles, multi-espèces, réactives sont résolues au sein du solveur CHOC-WAVES développé au CORIA, avec une thermodynamique variables et des coefficients de transport dépendant des espèces. La condition de Chapman-Jouguet généralisée a été élaborée et confirmée par les résultats de simulations numériques dans le cas d'une détonation multidimensionnelle stable. En particulier, il a été montré que les instabilités transverses s'atténuaient avec la réduction d'échelle. A cet effet, un scénario a été proposé pour expliquer le déficit de la vitesse du front de détonation, en se basant sur la structure de la poche subsonique aval, en corrélation avec l'épanouissement de la couche limite. Ce schéma partage de fortes similitudes avec la macro-détonation, tout en gardant des différences. En particulier, il a été montré que la forte vorticité, produite au niveau de la singularité de Prandtl-Meyer, souvent négligée dans les modèles de macro-détonation, diffusait au sein de la poche subsonique. Ces résultats tout à fait originaux ont permis une avancée significative dans la compréhension du mécanisme de propagation des fronts de détonation stables et confinées. / Progress towards the miniaturization of increasingly advanced micro- and nano-electromechanical systems has highlighted the need for a better knowledge of the design of such devices. knowledge of micro-nano pipe flows is still mandatory. In field of energy power generation, as the systems are scaled down, the thermal efficiency of conventional propellant devices is seriously degraded due to significant heat losses which can cause the combustion extinction. A promising approach is to use shock or detonation waves in gazeous media to enhance chemical reaction rates. A detonation is a rapid regime of burning in which a strong shock ignites the fuel and the burning proceeds to equlibrium behind the shock, while the energy released continues to drive the shock. It is also characterized by the presence of longitudinal and transverse instabilities, thereby subjecting the shock front to violent deceleration / acceleration. The objective of this thesis is to better understand the mean structure of the reaction zone that extends from the shock to the sonic surface. As for numerical modelling, the compressible multi-species reactive Navier-Stokes equations are solved using an in-house code "CHOC-WAVES", including variable thermodynamic and transport coefficients depending on the species. The Generalized Chapman-Jouguet condition was developed and corroborated by the numerical results in the case of stable multidimensionnal detonation. More specially, it was shown that the transverse instabilities are attenuated with the scale reduction.To this end, a scenarion, based on the structure of downstream subsonic pocket, which is correlated to the development of the boundary layer, has been proposed to explain the deificit of the detonation from velocity. This scheme shares many similarities with the macro-detonation, while keeping some differences. In particular, it was shown that the strong vorticity, generated at the Prandlt-Meyersingularity and often neglected in macro-detonation models, diffuses in the subsonic pocket. The present contribution enables us to shade more physical insight for the propagation of stable and confined detonation fronts.

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