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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.
261

Design počítačového tomografu / Design of Computer Tomography Scanner

Ronzová, Gabriela January 2013 (has links)
The presented master thesis concerns an own design concept of a CT scanner that meet the basic technical, ergonomical and social requirements and also brings a new look and shape as solution to the main topic.
262

Srovnání možných způsobů zásobování rodinného domu energií / Comparison of energy sources for energy supply of residential

Špatenka, Jindřich January 2014 (has links)
This diploma thesis deals with comparison of possible ways to supply the specific house by thermal energy. In the first part is a brief introduction of the building and determination of heat consumption. Following chapters are devoted to description and sorting of gas boilers, heat pumps, biomass boilers and solar collectors, inclusive the choice of specific source of heat. In the following part is stated economic evaluation of selected heat sources. Final part of the thesis is focused on design of additional exchanger instead of gas boiler.
263

Renovace RD na budovu s téměř nulovou spotřebou energie / Renovation of the Family House on the Nearly Zero-Energy Consumption Building

Bárta, Martin January 2016 (has links)
The diploma thesis contains by renovation of the family House on the “nearly zero-energy consumption building”, the proposal is for a variety of energy measures to achieve this status.
264

Vytápění bytového domu / Heating of flat house

Matoulková, Jana January 2017 (has links)
The point of the thesis was to design a heating system for new residential building, situated in Nový Lískovec, Brno. As a source of heat has been designed condensing boiler fueled by gas that meets the need for heating of heating system and hot water. All of the equipment will be located in a utility room on the ground floor. In the apartment have been designed decorative panel radiators.
265

Fault Detection AI For Solar Panels

Kurén, Jonathan, Leijon, Simon, Sigfridsson, Petter, Widén, Hampus January 2020 (has links)
The increased usage of solar panels worldwide highlights the importance of being able to detect faults in systems that use these panels. In this project, the historical power output (kWh) from solar panels combined with meteorological data was used to train a machine learning model to predict the expected power output of a given solar panel system. Using the expected power output, a comparison was made between the expected and the actual power output to analyze if the system was exposed to a fault. The result was that when applying the explained method an expected output could be created which closely resembled the actual output of a given solar panel system with some over- and undershooting. Consequentially, when simulating a fault (50% decrease of the power output), it was possible for the system to detect all faults if analyzed over a two-week period. These results show that it is possible to model the predicted output of a solar panel system with a machine learning model (using meteorological data) and use it to evaluate if the system is producing as much power as it should be. Improvements can be made to the system where adding additional meteorological data, increasing the precision of the meteorological data and training the machine learning model on more data are some of the options. / Med en ökande användning av solpaneler runt om i världen ökar även betydelsen av att kunna upptäcka driftstörningar i panelerna. Genom att utnyttja den historiska uteffekten (kWh) från solpaneler samt meteorologisk data används maskininlärningsmodeller för att förutspå den förväntade uteffekten för ett givet solpanelssystem. Den förväntade uteffekten används sedan i en jämförelse med den faktiska uteffekten för att upptäcka om en driftstörning har uppstått i systemet. Resultatet av att använda den här metoden är att en förväntad uteffekt som efterliknar den faktiska uteffekten modelleras. Följaktligen, när ett fel simuleras (50% minskning av uteffekt), så är det möjligt för systemet att hitta alla introducerade fel vid analys över ett tidsspann på två veckor. Dessa resultat visar att det är möjligt att modellera en förväntad uteffekt av ett solpanelssystem med en maskininlärningsmodell och att använda den för att utvärdera om systemet producerar så mycket uteffekt som det bör göra. Systemet kan förbättras på några vis där tilläggandet av fler meteorologiska parametrar, öka precision av den meteorologiska datan och träna maskininlärningsmodellen på mer data är några möjligheter.
266

Reducing CO2 emissions of conventional fuel cars by vehicle photovoltaic roofs

Lodi, Chiara, Seitsonen, Antti, Paffumi, Elena, De Gennaro, Michele, Huld, Thomas, Malfettani, Stefano 21 December 2020 (has links)
The European Union has adopted a range of policies aiming at reducing greenhouse gas emissions from road transport, including setting binding targets for tailpipe CO2 emissions for new light-duty fleets. The legislative framework for implementing such targets allows taking into account the CO2 savings from innovative technologies that cannot be adequately quantified by the standard test cycle CO2 measurement. This paper presents a methodology to define the average productivity of vehicle-mounted photovoltaic roofs and to quantify the resulting CO2 benefits for conventional combustion engine-powered passenger cars in the European Union. The method relies on the analysis of a large dataset of vehicles activity data, i.e. urban driving patterns acquired with GPS systems, combined with an assessment of the shading effect from physical obstacles and indoor parking. The results show that on average the vehicle photovoltaic roof receives 58% of the available solar radiation in real-world conditions, making it possible to reduce CO2 emissions from passenger cars in a range from 1% to 3%, assuming a storage capacity of 20% of the 12 V battery dedicated to solar energy. This methodology can be applied to other vehicles types, such as light and heavy-duty, as well as to different powertrain configurations, such as hybrid and full electric.
267

Utveckling av platta tak : Utvecklingsåtgärder som förbättrar och ökar användningen av platta tak / Development of flat roofs : Developing measures to improve and increase the use of flat roofs

Dzemidzic, Admir, Fuica Garrido, Leandro January 2015 (has links)
Detta examensarbete handlar om utvecklingsåtgärder på platta tak. Åtgärderna som tas upp är specifikt avsedda för två hustyper på Byälvsvägen i Bagarmossen, söder om Stockholm. Hustyperna är lamell- och loftgångshus som är byggda under slutet av miljonprogrammet. Båda hustyperna har platta tak med invändigt avvattningssystem. Taken ska inom några år läggas om på grund av slitage. Syftet med detta arbete är att ta fram och undersöka olika åtgärder för att utveckla, förbättra och öka användningen av de platta taken på loftgångs- och lamellhusen.   Examensarbetet har utförts med hjälp av litteraturstudier, intervjuer och studiebesök. För gestaltning av husen och de byggtekniska lösningarna har 3D-programmet autodesk Revit använts.   Arbetet innehåller förslag på utvecklingsåtgärder som är möjliga att utföra med eller utan förstärkning av tak och stomme. I arbetet tas det även fram byggtekniska lösningar på samtliga åtgärder.   Åtgärder utan förstärkning av tak och stomme: Utveckling av takutformning Utveckling av avrinningssystem Gröna tak (lätt sedumtak) Solceller   Åtgärder med förstärkning av tak och stomme: Gröna tak (intensivt tak) Påbyggnad av lägenheter eller radhus Ökad tillgänglighet i form av hiss och trappor / This thesis is about developing measures on flat roofs. The measures that are brought up are specifically designed for two types of houses on Byälvsvägen in Bagarmossen, south of Stockholm. The house types are balcony aces blocks and lamellar houses, both are built during the so called in Swedish “million program”. Both house types have flat roofs with internal drainage. The roofs will be renovated within a few years due to wear.   The purpose is to create and examine various measures to develop, improve and increase the use of the flat roofs of the balcony aces blocks and lamellar houses.   The work has been carried out with the help of literature studies, interviews and field trips. The 3D program software Autodesk revit has been used for the design of the houses and structural engineering.   The thesis includes suggestions for developing measures that are possible to apply, with and without reinforcement of the roof and frame. This thesis also brings up structural engineering solutions on all measures.    Measures without reinforcement of roof and frame: Development of roof structure Development of drainage system Green roofs (light sedum roofs) Solar panels   Measures with reinforcement of roof and frame: Green roofs (heavy roofs) Adding storeys of apartments or townhouses Availability in form of elevator and stairs
268

Light-weighting Methodology in Rail Vehicle Design through Introduction of Load Carrying Sandwich Panels

Wennberg, David January 2011 (has links)
Lightweight design in rail vehicles has been important for quite some time. Structures have been optimised to fulfill their purpose and cut unnecessary weight to reach allowable axle loads. Classically this is done by using steel, thin-walled structures, throughout the car body, or, alternatively, power-pressed aluminum profiles. The use of composites and sandwich structures has, however, been somewhat limited in the railway industry, especially when considering High-Speed trains. The anticipated weight savings, and reduced complexity of this type of structure are believed to have great potential in the future. This thesis covers the development of methods for structural stiffness design of lightweight, load carrying, sandwich panels for high-speed rail vehicles. Focusis on reducing the weight of the vehicles while simplifying the construction to reduce manufacturing costs and assembly times. Significant work is put into understanding the dynamic influence this type of structure has on the car body. / QC 20110516 / Multifunctional body panels
269

Energy efficiency measures in a typical Swedish single-family building from the 1960s

Larsson, Emanuel, Ljungqvist Baldesi, Raffaello January 2022 (has links)
Many buildings built in the 1960s are inefficient when it comes to their energy use. A lot of them are also in need of renovating. Therefore, this project is aiming to investigate five different scenarios where the decrease in electricity demand is in focus.One scenario is energy-saving behavior which does not need any investment for a renovation but just decreases the electricity demand by changing the behavior of the people living there.Another option is the building envelope renovation where added insulation to the outer walls, the roof and the floor is added. The windows and entrance doors are also upgraded to more efficient options. A return air only ventilation system is installed as well. The third option is to renovate the reference house to achieve the status of passive house set by Boverket. This is done by adding a much thicker layer of insulation to the building components and adding a FTX ventilation system and at the same time changing the direct electric heating system to a bed rock geothermal heating system. The last two scenarios, net-zero energy building and off-grid building, also use a FTX ventilation system and bed rock geothermal heating system. They have the same thickness as the building envelope renovation. The biggest difference is that the net-zero energy building uses solar power to match the yearly electricity demand and therefore be able to call it net-zero energy. The off-grid house has an electricity storage as well as the solar panels. This is to be able to disconnect from the electric grid completely and only consume electricity produced by the building itself.The last three scenarios all achieve a primary energy below that of what Boverket demand fornew buildings of 90 kWh/m^2, year. The building with the lowest cumulative cost over 50 years is the off-grid building, though this result could vary depending on the price of electricity. The scenario with the lowest investment cost per kWh saved is the net-zero energy building.
270

Case study of the energy performance of a school building in Laholm, Sweden : Energy modeling for the formulation of efficient renovation strategies

Gutiérrez Prieto, Daniel Andrés January 2022 (has links)
This study has been focusing on a school located in the municipality of Laholm, South of Sweden. Employing an energy balance of the last five (5) years, a proposal for measures is made in terms of performance for comparison with the baseline of the current consumption trend. This comparison allowed us to narrow down the alternatives for the renovation with the potential to have a great impact on the school's energy use and indoor environment, but also on the preserved characteristics without any violation of the laws and regulations. A complementary analysis was used to analyze important variables for decision-making and implementation of improvements. This analysis consists of an exergy analysis which was utilized as a pre-design tool for an optimized building renovation proposal. Exergy losses were calculated to assess the performance of the systems. The study revealed that in relation to the use of new technologies and materials, aerogel and vacuum insulation panels bring relevant savings as their insulation mechanisms are the most efficient for such a building in a climate like Laholm. As for the heating system, it was evident that the use of a geothermal heat pump associated to PV panels brings considerable energy benefits when compared to the current oil boiler system and given that the village does not yet have a local district heating system. When the proposed measures are applied during 2022- 2023, the results will show that also older buildings can be energy efficient which is demanded of the buildings stock throughout the European Union.

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