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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.
191

Kmitočtové filtry řízené mikroprocesory / Frequency filters controlled via microprocessors

Bronec, David January 2015 (has links)
This thesis is focused on the microprocessor-controlled frequency filter project. The main goal of the thesis is to present basic terms and principles of frequency filters and active frequency filters for cascading synthesis. Furthermore, the work contains information on digital potentiometers. The thesis includes circuit simulations and a project of connecting with a printed circuit board. The last chapter contains the results of the measurements.
192

Modifikace adaptéru na kukuřici na sklopnou verzi / Hinged adapter of corn header

Řezníček, Milan January 2012 (has links)
The master’s thesis contains a plan of hinged adapter for cord header Cornpower 8-75 of the BISO Schrattenecker Company. The adapter is designed for threshing machines New Holland. The thesis includes a comparison of the mechanisms used by competitors. Further it contains design of the entirely different mechanism, its kinematics solution of the hydraulic circuit and calculating of the strength using FEM method, including calculation of contacts. The drawing documentation is done in Catia V5 and strength calculations in NX-Ideas and Marc 2010.
193

Nová koncepce hydraulického pohonu CPB / New conception of hydraulic drive CPB

Bártek, Petr January 2013 (has links)
The main objective of this master's thesis is to design the new conception of hydraulic drive of the baling press CPB 100 with application of modern tendencies in the field of hydraulic engineering. This thesis contains design and calculations of new hydraulic drive, hydraulic circuit diagram and the list of hydraulic elements that are used. Moreover this thesis includes the design of an electrical control and the design of hydraulic block and manifold.
194

Protitlaková parní turbina / Backpressure Steam Turbine

Kubiš, Zdeněk January 2013 (has links)
The theme of the master’s thesis is to design a 60 MW single-casing steam turbine for the two-stage district water heating. The turbine is designed for cogeneration cycle, has four uncontrolled extractions and the outlet down to the heater. First, there is the thermodynamic calculation of the turbine operation with 100 % steam mass flow. Further, the detailed design of flow part with the strength calculation of blades and diaphragms is drawn. By the end of the thesis, the required operations are compared and corresponding heat balancing diagrams are listed. The thesis also includes a turbine longitudinal section.
195

Přívěs za traktor pro přepravu palivového dřeva a sypkého materiálu / Trailer for tractor to transport firewood and bulk material

Šetka, Martin January 2014 (has links)
The Master´s thesis deals with the engineering design of single-axle brakeless dump trailer for a tractor designed for transporting and dumping of particulate materials and firewood. The engineering design of the trailer is based on the proposed kinematic scheme and the basic calculations that are checked by FEM analysis in Ansys Workbench. The drawing documentation is done in AutoCAD.
196

Návrh konceptu montážní linky pro montáž vodních ventilů systému termoregulace motoru / Proposal for the new concept of assembling water ventilation systems of thermoregulation of a motor at an assembly line

Krátký, Lukáš January 2014 (has links)
The aim of this diploma thesis is processing of the design of the assembly line for assembling of water ventilation systems of thermoregulation of an engine. The proposal is comprised of determination of the line cycle time, required number of workers and a creation of three possible options of assembly line solution. The final variant will be chosen by using a multi-criterion evaluation.
197

Univerzální palubní počítač do auta / Universal Onboard Automotive Computer

Novohradský, Petr January 2015 (has links)
This work includes the complete design of a prototype embedded system for displaying information from a vehicle. ELM327 chip is described and its basic use. Work also describes the development of the diagnostic socket for  vehicles in European countries. Also contains a complete description of developing schematic, printed circuit board and firmware implementation. The thesis describes the use of realtime operating system in embedded system.
198

Parní kondenzační turbína s jedním regulovaným odběrem / Extraction Condensing Steam Turbine

Drápela, Jakub January 2016 (has links)
This diploma thesis describes a design of condensing steam turbine out of entered data of vapor parameters. There is selected a reaction blading type according to a conception of the company PBS Energo PLC. The turbine has one controlled extraction and three uncontrolled ones. The work also includes a proposal of thermal scheme, bearing and gearbox assignment. Furthermore there is also made a draft design of longitudinal section turbine
199

Evaluation formative du savoir-faire des apprenants à l'aide d'algorithmes de classification : application à l'électronique numérique / Formative evaluation of the learners' know-how using classification algorithms : application to th digital electronics

Tanana, Mariam 19 November 2009 (has links)
Lorsqu'un enseignant veut évaluer le savoir-faire des apprenants à l'aide d'un logiciel, il utilise souvent les systèmes Tutoriels Intelligents (STI). Or, les STI sont difficiles à développer et destinés à un domaine pédagogique très ciblé. Depuis plusieurs années, l'utilisation d'algorithmes de classification par apprentissage supervisé a été proposée pour évaluer le savoir des apprenants. Notre hypothèse est que ces mêmes algorithmes vont aussi nous permettre d'évaluer leur savoir-faire. Notre domaine d'application étant l'électronique numérique, nous proposons une mesure de similarité entre schémas électroniques et une bas d'apprentissage générée automatiquement. cette base d'apprentissage est composées de schémas électroniques pédagogiquement étiquetés "bons" ou "mauvais" avec des informations concernant le degré de simplification des erreurs commises. Finalement, l'utilisation d'un algorithme de classification simple (les k plus proches voisins) nous a permis de faire une évaluation des schémas électroniques dans la majorité des cas. / When a teacher wants to evaluate the know-how of the learners using a software, he often uses Intelligent Tutorial Systems (ITS). However, those systems are difficult to develop and intended for a very targeted educational domain. For several years, the used of supervised classification algorithms was proposed to estimate the learners' knowledge. From this fact, we assume that the same kinf of algorithms can help to adress the learners' know-how evaluation. Our application field being digital system design, we propose a similarity measure between digital circuits and instances issued from an automatically generated database. This database consists of electronic circuits pedagogically labelled "good" or "bad" with information concerning the simplification degrees or made mistakes. Finally, the use of a simple classification algorithm (namely k-nearest neighbours classifier) allowed us to achieve a circuit's evaluation in most cases.
200

Étude expérimentale et modélisation cinétique de la transformation d’éthanol en butadiène / Experimental study and kinetic modeling of the transformation of ethanol into butadiene

Dussol, Damien 04 November 2019 (has links)
Le butadiène est une molécule d’intérêt industriel qui peut être produite par le procédé dit Ostromislensky, avec l’éthanol en tant que matière première. Cette étude a pour objectif de développer un modèle cinétique pour expliquer la transformation d’un mélange éthanol/acétaldéhyde en butadiène, dans le cadre de la seconde étape de ce procédé. Le modèle cinétique est basé sur un schéma réactionnel et un modèle de réacteur. Le schéma proposé comprend la voie de Gorin Jones, communément acceptée dans la littérature, et une toute nouvelle voie impliquant un intermédiaire buténone. Les étapes clés ont été étudiées spécifiquement via des tests dédiés. Le schéma décrit aussi les étapes amenant aux principaux produits secondaires. Il a été validé à partir d’une base de données expérimentale, générée en amont de l’étude sur une unité de type gaz/solide, lit fixe, isobare (3 bara) et isotherme, avec un catalyseur Ta2O5 SiO2. L’influence des conditions opératoires sur l’effluent a été observée pour trois ratios éthanol/acétaldéhyde et sur des gammes de PPH (1,1 à 8,1 g·gcata 1·h-1) et de températures (320 à 370 °C). Le réacteur (piston dispersif sans limitations diffusionnelles) intégrant des lois cinétiques d’ordre, a été modélisé à l’état permanent via un solveur LSODE. Les paramètres cinétiques ont été estimés via un optimiseur Levenberg Marquardt à partir de la base de données expérimentale. Le modèle cinétique obtenu, basé sur un schéma réactionnel inédit, est en capacité de représenter et de prédire les débits des composés principaux et les tendances et ordre de grandeurs des débits des composés minoritaires selon les effets de PPH, de charge et de température, excepté dans certaines conditions opératoires limites isolées / Butadiene is a molecule of industrial interest that can be produced by the so-called Ostromislensky process, with ethanol as raw material. This study aims to develop a kinetic model to explain the transformation of an ethanol/acetaldehyde mixture into butadiene, as part of the second step of this process. The kinetic model is based on a reaction scheme and a reactor model. The proposed scheme includes the commonly accepted Gorin Jones pathway and a new pathway involving a butenone intermediate. The key steps were specifically studied via dedicated experiments. The scheme describes also steps leading to by products. It was validated from an experimental database, generated upstream of the study on a gas / solid type unit, fixed bed, isobaric (3 bara) and isothermal, with a Ta2O5 SiO2 catalyst. The influence of the operating conditions on the effluent was observed for three ethanol/acetaldehyde ratios and over ranges of PPH (1.1 to 8.1 g·gcata 1·h-1) and temperatures (320 to 370 °C). The reactor (plug flow without diffusional limitations) integrating kinetic laws of order, was modeled in the permanent state via a solver LSODE. Kinetic parameters were estimated via a Levenberg Marquardt optimizer from the experimental database. The kinetic model obtained, based on a brand new reaction scheme, is able to represent and predict the flow rates of the main compounds and the trends and orders of magnitude of the flow rates of the minority compounds according to the effects of PPH, charge and temperature, except under certain isolated operating conditions

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