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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.
231

Automatizace trati pro měření vodních ventilů / Automation of track for measurement of water valves characteristics

Lekeš, Pavel January 2014 (has links)
My diploma thesis describes upgrade of flowbench serving as test rig for regulation valves characteristic measurement. At the beggining, there is an introduction to the water regulation valves theory followed by current machine condition description. Next chapter defines needed improvements and at the end follows proposition of improvements and necessary component definition and final realization. Final chapter summarizes complete project.
232

Výpočet stejnosměrného elektromagnetu a jeho experimentální ověření / Calculation of DC electromagnet and its experimental verification

Steidl, Adam January 2015 (has links)
Content of this thesis deals with electromagnets as operating elements in electric machines. Thesis is divided in two main parts, theoretical and practical. The theoretical part describes electromagnets as electric machine , usage of electromagnets in electrical devices as operating element. Electromagnets are further divided in groups on basis of different criteria. Next, the theory of electromagnetic fields and methods of assesment of static pull and dynamic characteristics is described. Construction and function analysis of researched electromagnet with permanent magnets, which serves as trigger in compact circuit breaker, is also included in this part. Practical part includes measurement of force quantities of researched electromagnet in different operating states an its evaluation. For analysis of dynamic quantities with finite element method were created two-dimensional and three-dimensional models. Evaluation of analysis follows. After that is described simplified design of electromagnet, based onoperating states of researched electromagnet. This part is closed with comparation between results of analysis and designed values of electromagnets.
233

Výpočet stejnosměrného elektromagnetu a jeho experimentální ověření / Calculation of DC electromagnet and its experimental verification

Steidl, Adam January 2015 (has links)
Content of this thesis deals with electromagnets as operating elements in electric machines. Thesis is divided in two main parts, theoretical and practical. The theoretical part describes electromagnets as an electric machine, usage of electromagnets in electrical devices as operating element. Electromagnets are further divided in groups on the basis of different criteria. Next, the theory of electromagnetic fields and methods of assesment of static pull and dynamic characteristics are described. Construction and function analysis of researched type of electromagnet from OEZ company with permanent magnets, which serves as trigger in compact circuit breaker, is also included in this part. Practical part includes measurement of force quantities of an electromagnet in different operating states and its evaluation. For analysis of dynamic quantities with finite element method was created suitable three-dimensional model of electromgnet. Model is used for simulation ofdifferent operating states.The last part describes measurement of dynamic characteristics of the electromganetic system. This part is closed with comparation of results.
234

Dopravní charakteristiky v uspořádání 2+1 / Traffic characteristics of 2+1 arrangement

Kabeš, Luboš January 2015 (has links)
The thesis discusses the roads in lanes 2 + 1 arrangement in the country and abroad. It focuses primarily analogy of this type of arrangement in our situation, ie on stretches of roads I. classes with an increased number of lanes for slow vehicles to climb. Part of this work is to verify some of the traffic, including traffic flow characteristics compared to conventional two-lane roads, especially in terms of: sectional speed; overtaking; Accident and dependence longitudinal gradient. The work aims to evaluate the foreign experience and achievements of domestic communications options for application configuration 2 + 1 in the Czech Republic.
235

Návrh repliky letounu L-40 "Meta Sokol" - základní rozměry - technologie / Replica design of Aircraft "Meta Sokol" - Basic dimensions - technology

Lipková, Alica January 2008 (has links)
The object of the diploma thesis is a preparation of fundamentals for realization for replica of the aircraft L-40 „Meta Sokol“ matching the requirements of Certification Specification for Very Light Aeroplanes (CS-VLA). The preamble of the work deals with the changes made on the original aircraft necessary to satisfy the criterias of the above-mentioned specification. One of the main contents of the first part of the thesis is the definition of replica’s basic dimensions and preparation of aerostatic fundamentals, including longitudinal stability control. As next a suitable engine is chosen and calculation of corresponding performances is made. A detailed weight analysis and a determination of centre of gravity position (c.g. position), important for solving the stability of an airplane, is also presented. Finally, a brief description of the manufacturing process of individual components and also factors influencing the technology are discussed.
236

Kondenzační parní turbina / Condensing Steam Turbine

Kracík, Petr January 2011 (has links)
Diploma thesis named Condensing steam turbine deals with heat scheme balancing computation of condensing steam turbine K55 and her design. This turbine with 5 unregulated take-offs and overpressure blading type, is computed with (c_a/u) method in the middle of blading diameter. Regulation degree is chosen with impulse blading and feet cross section is checked on durability. At the end of the thesis turbine consumption characteristic is derived from the zero output up to the nominal output. Integrated part of this thesis is conceptional design of longitudal turbine section.
237

Obrobitelnost litiny s lupínkovým grafitem pro brzdové díly firmy RENAULT / Characterization of the machinability of cast iron for the RENAULT’s brake discs

Ceyte, Benoit January 2011 (has links)
This document is final report of an expertise project lead for ALPHA Company. The project focuses on the machinability characterization and comparison of various lamellar cast irons metallurgies. The comparison is performed in order to improve the casting process and the cast irons composition of brake and hub disk, to increase their machinability. The characterization of the metallurgies was made by tool life test with measurements of the cutting forces. Hardness and surface roughness measurements were performed too. Several Silicon nitride tools were tested. First an adjustment test has been performed to validate the machining parameters, and the methodology of characterization. Secondly, a reference test on Alpha’s cast iron brought reference data for the comparison of the various metallurgies to be tested. This test has improved the method of characterization. Cutting forces recording appeared as the most relevant and irrelevant measurements such as surface roughness were eliminated from the method. A test performed on a second cast iron showed that it has a lower machinability. Project succeeded to characterize and compare cast irons’ machinabilities, allowing the improvement of the composition by further tests.
238

Vliv délky lopatky virové turbíny na její charakteristiku / The affect of the blade length on the swirl turbine characteristic

Pavlíček, Jan January 2014 (has links)
This thesis deals with the evaluation of swirl turbine measurement, which the length of the turbine blades was gradually reduced. The subject of the effect was influence of the length of the blades, especially the measured efficiency of the turbine, and the character assessment of the flow at the inlet and outlet of the impeller. The measured data were analysed using the computing workbook with macro support, which can be used to evaluate other measurements of similar character. The different behaviour of the turbine depending on the length of the blades of the impeller was shown in the characteristics of the turbine and velocity triangles. For the variant with the best efficiency achieved was constructed QH diagram used in the design of turbine parameters for a particular location.
239

Trakční pohony s asynchronním motorem / Traction Drives with Asynchronous Motors

Běloušek, Josef January 2013 (has links)
The first part of this work is devoted to the design of a traction asynchronous motor. The second part focuses on the developed method of the equivalent circuit parameters identification of the asynchronous motor in the form of -network. It is explained here that the equivalent circuit in the shape of a -network, alternatively of an inverse 'I-network, is exactly equivalent and fully-fledged to a T-network, although one of two stray inductances is formally missing. Furthermore, the relationships for the conversions of the T-network parameters to the -network parameters and back, and of the T-network to the inverse 'I-network and back are found. The third part deals with the calculation of the torque and the current characteristics of the asynchronous motor. A sensitive analysis of the torque characteristic is carried out on the individual parameters of the equivalent circuit of the asynchronous motor in the form of a -network and a method of the measurement by means of a flywheel is used for the torque characteristic measurement of the asynchronous motor. The fourth part focuses on the verification of the identified -network parameters in the Matlab-model of the traction drive.
240

Ověření provozní výkonnosti a optimalizace FVE / PV plant performance evaluation and optimization

Špinar, Marek January 2016 (has links)
The Master´s thesis deals with issues of operational performance of two photovoltaic power plants. In the thesis is stated the history of photovoltaics, description of photovoltaic effect, used materials and production technology of the most used material in PV industry – Silicon. The basic parts and parameters of photovoltaic power plant are described. Thesis also solves, how could be done the first and periodically control due to relevant directives. The ways of diagnostics potentional failures, methods of measuring and the exam of monitoring system are stated. Practice part is focused on measuring and comparing operational performance of FVE Kurdějov and FVE Šakvice II. Operational performance was calculated from exported data for years 2014 and 2015. The thesis also contains measuring of each string connected to inventors, which are installed on the power plant. The result is an identification of strings with decreased operational performance. Based on that was created recommendations for optimalization and increase of the performance. The last part is software for simulation of photovoltaic power plant. This SW calculates potentional energy, which could be produced in a day with available data export. The calculation is defined by parameters, which are assigned.

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