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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.
291

Příběhy Nerudových lásek v povědomí školy a veřejnosti / Stories of Neruda's love affairs in awareness of school and public

Kubandová, Jindřiška January 2012 (has links)
The main focus of this disertation are relationships of Jan Neruda. They are explained from two different points of view: historical and didactic. The historical part is about the facts, for which the evidence can be found. Those that don't have any evidence in the historical sources are separated. In this part there were also discussed some novels, which portray Jan Neruda. The didactic part contains of the analysis of the textbooks, there was studied, how the information about Neruda's relationships were explained to the students. The last chapter is about websites, where the information about this topic can be found. This topic was there also assessed from the historical and didactic point of view.
292

Bioplynové stanice - forma obnovitelných zdrojů energie / Biogas stations - renewable energy sources

VOBORSKÁ, Petra January 2014 (has links)
The topic of the thesis is biogas stations - renewable energy sources. This thesis focuses on energy from biomass which is generated inside stations, and on appropriate use of energy. It deals with thermal energy that is produced as a waste product inside the biogas stations. The main objective is to evaluate the effectiveness of the biogas stations as a source of heat for the municipalities in southern Bohemian and create evaluation criteria of suitability of using heat from biogas stations in specific communities.
293

Využití výživových suplementů v jednotlivých sportovních odvětvích / Use of Nutritional Supplements in Individual Sport Sectors

Weiser, Martin January 2015 (has links)
The aim of the diploma thesis was to determine, which nutritional supplements are selected by athletes of strength and endurance sports branches and what is the reason for their option. The theoretical part characterizes the 8 selected sports sector from point of view of the sport performance structure. There is also mentioned the issue of nutritional supplements, their division, legislation or general recommendations for the use in sport. The last chapter deals with the requirements for the use of nutritional supplements in different periods with respect to the branche of sport. Research part has specifically determined the nutritional strategy for athletes in the field of mentioned food supplements at strength and endurance-oriented sports disciplines by using the questionnaire. The research is supported by an interview with an expert nutritionist and sports through collaboration with the staff of the Centre for Sports of the Ministry of Interior
294

Návrh otopné soustavy a nuceného větrání pro dvougenerační vilu / Space heating and ventilation in a two-generation house

Kazda, Jan January 2018 (has links)
This Master's thesis deals with the evaluation of a current state of two-generation villa and its following proposal of the optimization. Evaluation includes calculation of heat loss of a current state. Optimization is based on the reduction of heat loss in the building, pressure balance of the system, change of heat source and installation of balanced ventilation. Chapter describing regulation of technology follows and in conclusion indicative price for the whole suggested technology is calculated.
295

Vytápění bytového domu / Heating of flat house

Jára, Marek January 2020 (has links)
The theme of this diploma thesis is to design heating of the flat house. The theoretical part of this diploma thesis is about exhaust gases paths. The calculation part of this diploma thesis contains the design of the heating system by panel heaters, floor convectors and underfloor heating system. The heat source is the system of cascade-connected gas condensing boilers. The rest of this part are the calculations of the preparation of hot water, design of hot water storage tank and another necessary equipment of the system. The part Project is about technical report and simulation of behaviour of underfloor heating system in various marginal conditions.
296

Spínané zdroje / Switched Mode Power Supplies

Španěl, Petr January 2020 (has links)
This thesis deals with switched mode power supplies based on resonant principle to achieve high efficiency. Several ways of switched mode power supplies optimalisation are described as part of the work to achieve better efficiency. Priparily, the new generation of switching elements based on SiC and resonant topology are used to achieve significant switching loss minimization. The selected resonant topology is simualted in detail and then built with focus on high efficiency. The main content of the work consists in the design and realization of the switched mode power supply with selected control algorithms and their comparison. The problems associated with usage of new SiC MOSFET generation in TO-247-4L package are being solved within the design and implementation of the power source. To solve the main problems, new 3rd SiC MOSFET gate driver was developer for working with switching frequencies in hundreds of kHz and resisting very high voltage stress on the controlled transistor. The next part of the gate driver is the overcurrent protection. The overcurrent limit can be set easily by changing one component. This protection reacts very quickly in hundreds of nanoseconds, so it is capable of saving the converter even in branch failure and going to hard short circuit. The functional sample of the series resonant converter was built and revated in the work. The converter based on 3. Generation of SiC MOSFET transistors from Cree in a modern case TO-247-4L was built. For this inverter, it was also necessary to develop both the control scheme and the resonance frequency tracking to achieve accurate switching and thus achieve the use of the resonant principle of the converter to the maximum extent possible. The result of this work is up to 3 kW converter with adjustable output voltage while maintaining high efficiency up to 96%.
297

Hasičská zbrojnice a tělocvična / Fire station with gym

Svoboda, Martin Unknown Date (has links)
The aim of the work is to design Fire station with a gym in Olomouc. Diploma thesis has three parts. First from institute of building structures, second from intitute of building services and last part is devoted to modeling and assessment of details of building. Fire station is divided into three parts. Garage for 3 fire trucks, main part and gym with training tower. The main part contains toilets, showers, locker rooms, storage places, offices and facilities for firefighters and office rooms. Structural elements of the building are from reinforced concrete. Infill walls are made from ceramic bloks. Thermal insulation is from mineral wool and cladding of the wall is made of fibre-cement boards. The slab in the main part is made of cast-in-place concrete. Others slabs in the garage and gym are made of prefabricated elements. On the building are desined three types of roofs. Extensive green roof, flat roof with a stabilization layer of river aggregates and roof made of insulating sandwich panels. In the thesis is design conception of artificial lighting, ventilating, heating, cooling, water managment, photovoltaics and management scheme of energy and ecological systems. The work contains project documentation for building permits, which were made in accordance with applicable legal and technical regulations.
298

Nízkofrekvenční zesilovač ve třídě D pro aktivní reproduktory / Class D audio amplifier for active loudspeakers

Cupák, Jan January 2011 (has links)
This master's thesis deals with design of D class audio final amplifier, which was output power 400 W for 4 ? load impedance. Designed audio amplifier is specifical for active speaker, which consists of satelite speakers and subwoofer. Further more it deals also with other functional blocks, e.g. balanced input preamplifier, active crossover and protection for safety running. Outcome of this work are schemes of each functional blocks of D class audio amplifier, whose functionality was verified by simulation. Thesis also contains full reference material including mechanical arrangement of functional blocks on printed connection board. The conclusion contains the measured parameters of function blocks of produced prototype and complete photographic documentation.
299

Fotometrie a spektroradiometrie zapouzdřených LED čipů / Photometry and spectroradiometry of LEDs

Vysoudil, Martin January 2012 (has links)
This thesis deals with the processing of light technical parameters and performance of key LED chips for their applications in lighting systems. The aim is to create a laboratory model for measuring the qualitative and quantitative parameters of highly luminous light LED emitted depending on the angle, using a spherical integrator 0.3 m, goniometer and fiber spektroradiometr /luxmeters. Goniometer is designed using modular optomechanical parts company Thorlabs. Due to the current passing through the LED chips heat up considerably. To light LED chip parameters tested were not affected by heat from the chip is required to pay the heat generated by a passive radiator. Another part of this thesis is the reconstruction of an older model spherical integrator. Reconstruction must be undertaken so as to ensure sufficient cooling again tested LEDs. Light scattered in the ball of the integrator is led by the optical cable to the spektroradiometr that are subsequently recorded its parameters. The second element used to measure the light produced by the LED source is photocell. Spherical integrator must be appropriately modified to indicate the two measuring elements and also meet the standards of determining the correctness of measurement. At the end of the measurement results will be compared with catalog values provided by the manufacturer.
300

Ověřovací série rychlonabíječů pro olověné akumulátory 12V a 6V / Verification series of fast-chargers for lead-acid accumulators 12V and 6V

Benada, Tomáš January 2012 (has links)
This thesis is an engineering design of an intelligent fast-charger for lead-acid accumulators. It contains calculations of each component. The switching power supply is the mainstay of the charger that makes the charger portable, lightweight and small. The Intelligent fast-charger for lead-acid accumulators charges the accumulator by method of constant voltage with current limitation of 0,5A, 5A, 10A, 50A. 50A current is used in winter during starting of a car, when the battery can´t provide sufficient current. There are three LEDs placed on the front side of the charger reflecting status of the device. The device comprises safety protection for the charger, supply network and battery.

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