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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.
511

Roof and Wall Vents Study under Simulated Hurricane Winds

Kawade, Peeyush S. 09 December 2009 (has links)
Ventilation might seem like a minor consideration, but when properly installed, it can extend the life of the attic and roof structure of residential buildings saving huge dollar amounts in repair costs. The objectives of this study were to measure the wind effect on different kind of vents as the problem is vents are subjected to high wind loads during hurricane events and often fail causing water penetration and damage of interior contents. Wind-induced failure of rooftop vents during a hurricane may result in large openings in the roof that will allow water to penetrate into the building, a puncturing of the roof membrane, again allowing water infiltration, and detached rooftop vents can pose considerable threats as windborne debris. The study found that water infiltration through a vent system is dependent upon the differential pressure as well as the vent mechanism. For vents experiencing higher differential pressures, vent covers can be used during storms to reduce water infiltration. Active controls can also be designed to close the vents automatically as differential pressure increases based on the wind speed and wind angle of attack.
512

Přestavba letounu VUT 051 RAY na dvoumotorovou variantu / Rebuilding of VUT 051 RAY into twin-engine conception

Jílek, Jan January 2018 (has links)
The master’s thesis is dealt with the design of rebuilding of VUT 051 RAY which is equipped electric powerplant to twin-engine conception named VUT 051 RAY-DUO. In the thesis was verified the range of centre of gravity position of VUT 051 RAY-DUO then powerplant in ducted fan configuration was designed, performances of the airplane were appointed and controllability during fail one of the engines was analysed. The design of new powerplant was verified by strength analysis and then costing calculation was established.
513

Tepelné čerpadlo pro ohřev teplé vody / Heat pump water heater

Mazálek, Karel January 2018 (has links)
This Master's thesis deals with reusing waste heat from the kitchen and .cold rooms of a restaurant, as a source of heat for heat pump water heater. The first part is about basic principles and theory which is needed to understand the function of heat pump and possibilities of reusing wasted heat. In the other parts, there are calculations and designs not only of a heat pump, but also coolers and ventilation unit needed for recycling of heat.
514

Návrh marketingové strategie / Marketing Strategy Proposal

Krejčíčková, Lucie January 2020 (has links)
The thesis focuses on the current marketing strategy of the professional hockey club HC Vítkovice Ridera with the aim of proposing changes in the marketing strategy that the club could use in the coming season. Based on theoretical knowledge, a situation analysis is developed, which evaluates the current state. This analysis is then supported by a questionnaire survey. The final part of the work is focused on recommendations for the club.
515

Transmedia storytelling in the music industry : The case of BTS

Zuhadmono, Alvia January 2021 (has links)
This case study research examines the impact of transmedia storytelling on the global reach of Korean-pop (K-pop) group BTS (Bangtan sonyeondan) and how narratives within the transmedia storyworld can motivate the audience to seek individual and social change. This study is inspired by the rise of BTS in the global music industry. The group came with a solid brand image, highlighting sincerity and authenticity that captivate audiences worldwide. BTS consistent messages—that intersect with sustainability issues—about the importance of loving oneself, equality, social justice, anxiety, and wellbeing are communicated through multiple platforms and travel across language and cultural barriers. To understand the context, this study uses the concepts of transmedia storytelling and audience engagement by Jenkins (2006, 2007, 2012, 2014), Gambarato (2019), Broesma (2019), and Askwith (2007), to name a few. The method used to conduct this research is the analytical and operational model of transmedia design by Gambarato et al. (2020). The findings are that transmedia storytelling —with spreadability, drillability, extractability, and immersion characteristics—is an effective communication strategy that significantly influences the global reach of the group. Further, the camaraderie between BTS and ARMY generates fan activism—an epitome of individual change due to the fondness to BTS, as the act of identification and the attitude of giving back to the intimacy that BTS members provide to the fandom.
516

Program pro výpočet ventilace a oteplení synchronních strojů / Program for calculation of ventilation and heating in synchronous machine

Kolář, Pavel January 2009 (has links)
This master´s thesis deals with ventilation of synchronous generators with a cylindrical rotor. For the design of ventilation we apply basic physical laws in the field of hydromechanics and thermomechanics. Therefore the first chapters are devoted to these subjects. They are followed by the description of ventilation systems and a thermal net is created and solved for one of them consisting of the thermal resistance and sources. The final part deals with a program, which I developed in Visual Basic 2008 Express Edition. This program enables to calculate the ventilation and heating of individual parts of the machine after entering basic machine dimensions and losses.
517

Ventilační výpočty v synchronním stroji / Ventilation calculations in synchronous machine

Judas, Jan January 2012 (has links)
The aim of the project was to get familiar with the environment of ANSYS CFX, create several models of fans and synchronous machine model in Autodesk inventor, create model of cooling medium flow through the machine with these fans and evaluation of results. Firstly the thesis describes the synchronous machine itself, losses of the machine, the flow of power of synchronous machine and methods of its cooling. Next the thesis describes each kind of heat transfer, laminar and turbulent flow. The thesis also refers of kind of the fans and the program used to calculate the flow Ansys CFX, including the method that Ansys used to calculate. The work describes the individual modification of fans and setting of calculation in ANSYS. Then displays the results of the analysis these fans for different numbers of fan blades and for modification of the fan. Then the thesis analyzes selected modifications due to changing speed. In the last chapter shows the analysis of flow in the machine with three different fans. In particular, there is shown the mass flow rate, pressure and its distribution on areas for evaluation.
518

Třírotorový lopatkový stroj pro klimatizační systém / 3-wheel air cycle machine

Vrána, Jan January 2012 (has links)
For air cooling in aircrafts is used an air cycle machine. Recently, there is focusing on incresing efficiency of air cycle and due this are added another rotors. Design of machine with three rotors is performed in this thesis.
519

Využití termoelektrického generátoru pro zvýšení účinnosti otopného tělesa / Using thermoelectric generator to increase the efficiency of the radiator

Kříž, Pavel January 2015 (has links)
This diploma thesis deals with a design layout of the fan power supply that ensures the increase of the efficiency of the heating unit. For usage in the areas without electric power, the power supply is secured by thermoelectric generator. The system has to function on the basis of autonomous system which turns itself on only when necessary. In the introductory part of the paper there is a recherché of thermoelectric generators for general usage. Next it mentions the basic findings in from the field of DC/DC converters for low power applications. In this part attention is given to MPPT algorithm. Furthermore basic knowledge from the field of heat transmission together with its most used elements is described. Subsequently existing applications that increase the effectiveness of heating are mentioned. Their disadvantage however is that they depend on the external source of power supply. The practical part to a large extent covers the analysis of the suitability of the chosen thermoelectric module. For securing of the heat gradient of the generator there was a model created meeting the figures in the manual and there are several simulations in the MATLAB program. Furthermore several measurements of the thermoelectric module took place in order to secure realistic figures. Subsequently a DC/DC converter was chosen. Finally the testing was made on the real composition. In conclusion there is an overall evaluation including the real usage and the economical aspect of the project. The outcomes of the work enable to avoid common mistakes that are part of many specialized articles. The created system is to be used after the adjustment of the cooling to the required aim. At the same time it becomes very effective.
520

Model pro určení směrovosti šíření zvuku / Sound emission directivity model

Zdvyhal, Marian January 2016 (has links)
This diploma thesis solves creation of a computing model of sound propagation for determination of acoustic pressure level around multiple point sound source with consideration of sound directivity of each source (compresor and fan). Thesis contains neccesary theoretical knowledge for creation of computing model and basics of sound measuring, theoretical computing model, measurement data of real unit and model configuration for real measured values. Computing code of the model in Visual Basic for MS Excel is a part of the thesis.

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