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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.
41

Algumas aplicações de jogos topológicos à análise / Some applications of topological games to analysis

Juan Luis Jaisuño Fuentes Maguiña 17 May 2018 (has links)
Neste trabalho apresentamos alguns jogos topológicos e suas aplicações à análise. Com esse fim, se fornece condições necessárias para que funções aproximadamente contínuas se tornem contínuas, se caracteriza os conjuntos estritamente pseudo-completos nos espaços de Banach e, assim também, se constrói um espaço de diferenciabilidade Gâteaux que não é Asplund fraco. / In this work we present some topological games and their applications to analysis. For this purpose, necessary conditions are given for nearly continuous functions to become continuous, we characterize the strictly pseudo-complete sets in the Banach spaces and we also construct a Gâteaux differentiability space that is not weak Asplund.
42

Vytápění domu s "téměř nulovou spotřebou" energie / Heating the house with "nearly zero" energy consuption

Lacina, Martin January 2013 (has links)
The main content of this master thesis is the proposition for the heating of a multi-purpose building. The aim of this project is to find the best way how to manage heating with "nearly zero" energy consumption. In the first part of the thesis there is a description of currently the most common systems leading to energy savings. The second part consists of three possible technical alternatives, containing technical solutions for this particular building with the regard to the requirements of the task. The third part then consists of the chosen solution.
43

Energibesparing med bergvärmepump och värmeväxlare : Månadsvisa beräkningar för ett nytt och ett äldre småhus i Västerås samt en jämförelse mot kraven för nära-nollenergibyggnader

Hilbert Wiman, Sara January 2021 (has links)
Purpose: This degree project aims to see how the energy demand from active heating of detached houses can be improved to meet the energy performance requirements set for nearly zero-energy buildings by Boverket (The Swedish National Board of Housing, Building and Planning). Method: To accomplish this, the benefits from two different energy-saving installations are studied: bedrock heat pumps and heat exchangers in Heat Recovery Ventilation Systems (HRV-systems). These are then compared in a new and an older detached house with very different heat losses. There are several reports of energy-saving systems in detached houses. What distinguishes this work is that it compares the specific results from the added energy-saving system depending on whether it was added first or last. The older detached house is an important part of this work as it represents a possible impact on parts of the existing housing stock with a similar technical standard. The energy balance for the buildings is calculated monthly with all contributions from passive heat considered, and with the energy demand for active heating as the main result. Results: It is very difficult to meet the energy performance requirements for an older detached house without extensive measures or renovations. The HRV-system had a low to very low impact. Both types of detached houses have a lot to gain from an investment in bedrock heating, especially the older one that has high energy demands. However, the new detached house with a higher technical standard in the building envelope, was the only one to meet the energy requirements with the bedrock heat pump on its own. Conclusion: Bedrock heating can be a very profitable investment as it provides heat both for the active heating of the building as well as for the domestic hot water. In order to meet tougher energy requirements, the bedrock heat pump may need to be accompanied by an improved and more energy-efficient building envelope and the supply of self-produced electricity, such as solar cells. HRV-systems require a good air tightness and an energy-efficient building envelope to be profitable. In older detached houses, it is not a profitable investment, as it does not have sufficiently large proportions of controlled ventilation to work with. In newer houses the proportion of controlled ventilation is bigger, but the amount of heat loss that can be affected is still not as big as the energy savings a bedrock heat pump can bring.
44

Environmentální řešení administrativního objektu v Hodoníně / Environmental solution of administrative building in Hodonín

Snášel, Michal Unknown Date (has links)
The aim of this master thesis is to design a seven-storey office building in Hodonín, Czechia. The building has retail spaces in the basement and first floor and offices in second to sixth floors and utility room and elevator engine room in the seventh floor. Individual floors are accessible via stairs and elevator. The vertical load-bearing structure consists of reinforced concrete walls and columns. Horizontal load-bearing structure consists of cast-in-place reinforced concrete slabs. The roof is flat with photovoltaic power plant connected to main battery. The main source of heating energy for the building is a heat pump (air-water) backed by a secondary electric boiler. Fresh air is supplied by a HVAC unit installed on the roof. Overheating due to solar heat gains and equipment is mitigated by local AC ceiling units. Automated roller blinds reacting to solar gains and glare are installed over the windows. The next part of thesis consists of comparison of pressure properties of sheet metal duct and CLIMAVER system.
45

[en] DISCUSSION OF THE POSSIBILITIES TO ACHIEVE A NEARLY ZERO ENERGY BUILDING (NZEB) USING THE BIM APPROACH / [pt] DISCUSSÃO DAS POSSIBILIDADES DE OBTENÇÃO DE UM EDIFÍCIO COM BALANÇO DE ENERGIA PRÓXIMO A ZERO (NZEB) USANDO A ABORDAGEM BIM

ALEXANDRE SANTANA CRUZ 28 December 2020 (has links)
[pt] Uma arquitetura que exige uma enorme demanda de energia contraria o conceito de um Edifício de Energia Quase Zero (em inglês Nearly Zero Energy Building - NZEB). Pesquisas indicam que edifícios de alto desempenho podem ser alcançados com um design integrado que combina estratégias de eficiência energética, como vidro de alto desempenho, com energia fotovoltaica. A metodologia BIM pode incorporar a Análise de Desempenho do Edifício para apoiar a tomada de decisão de um projeto integrado, essa abordagem é considerada essencial para alcançar um NZEB bem-sucedido. A presente investigação inclui uma revisão sistemática da literatura que orientou a pesquisa. Com base na SLR, foi desenvolvido um Manual de Entrega de Informações que propõe um novo fluxo de trabalho no qual os estudos de energia são realizados nos estágios iniciais do design para alcançar projetos com maior eficiência energética e aproveitar a colaboração intrínseca à metodologia BIM. Por fim, é apresentado um experimento hipotético de um edifício comercial para ilustrar o fluxo de trabalho proposto no IDM desenvolvido. O software Autodesk Revit foi usado para modelar o edifício e a simulação energética foi realizada no software DesignBuilder. Verificou-se que, para que esses dois softwares fossem interoperáveis, o modelo precisava ser exportado do Revit no formato gbXML. As opções de design foram baseadas na proporção de janela/parede (30 por cento, 50 por cento e 100 por cento), no vidro adotado e no sistema fotovoltaico. A análise de viabilidade econômica foi realizada com base no Valor Presente Líquido e na Taxa Interna de Retorno. Os resultados indicaram que o uso da fachada norte para produção fotovoltaica combinado com o sistema fotovoltaico da cobertura forneceu um balanço de energia próximo de zero na maioria dos casos. Por fim, todos os casos analisados têm um tempo de retorno de investimento inferior a garantia do fabricante dos módulos fotovoltaicos (25 anos), exceto no caso com 100 por cento de relação janela/parede e vidro PV na fachada norte. / [en] An architecture that requires a huge energy demand goes against the concept of a Nearly Zero Energy Building (NZEB). Research on the subject indicates that high performing buildings can be achieved with an integrated design that combines energy efficiency strategies, such as high performing glass, with photovoltaic energy (PV). The Building Information Modeling (BIM) methodology can incorporate Building Performance (BP) analysis to support decision making of an integrated design, which is considered essential to achieve a successful NZEB. The present investigation includes a Systematic Literature Review (SLR) that guided the research. Based on the SLR, an Information Delivery Manual was developed that propose a new workflow in which the energy studies are performed in the early stages of design to achieve more energy efficient projects and take advantage of the collaboration intrinsic to the BIM methodology. Lastly, a hypothetical experiment of a commercial building is presented to illustrate the workflow proposed in the developed IDM. The Autodesk Revit software was used to model the building and the energy computer simulation was performed in the DesignBuilder software. It was found that for these two software tools to be interoperable, the model had to be exported from Revit in gbXML format. The design options in the experiment were based on window-to-wall ratio (30 per cent, 50 per cent and 100 per cent), on the adopted glass, and on the photovoltaic system. The economic feasibility analysis was performed based in the Net Present Value (NPV) and the Internal Rate of Return (IRR). The results indicated that the use of the north facade for PV production combining with the PV roof system provided a nearly zero energy balance in most of the cases. Finally, all cases analyzed had a payback time of less than the PV module manufacturer guarantee (25 years), except for the case with 100 per cent window-to-wall ratio and PV Glass in the north facade.
46

Retrofitting a Single-family Home with Increased Use of Renewable Energy

Ma, Chenwen January 2017 (has links)
Buildings account for up to 40% of the total energy use in the world. Directives from the European Union have pointed out the significance of increasing the energy efficiency in buildings. New regulation in countries like Sweden has established that new buildings should fulfil regulations of Nearly Zero Energy Buildings (NZEB), providing the opportunity for renewable energy technologies to achieve these goals. In this paper, the retrofitting potential of renewable energy technologies for a single-family home in Sweden was investigated.The present work studied the characteristics of several renewable energy technologies and their applications for a single-family home in Sweden, including biomass, solar photovoltaics, solar thermal, heat pump, and small-scale wind turbine. Three renewable energy technologies (solar thermal, heat pump and small-scale wind turbine) and one renovation method (window) were selected to investigate. The analysis was made of the current energy use and the potential energy (and cost) savings from each retrofitting of these facilities by means of simulation models using IDA ICE software. The study results show that the proposed renewable energy technologies are technically feasible and economically viable as a source of alternative renewable energy in order to produce clean energy and reduce electricity bills for an electric-heated single-family home located in Sweden. Moreover, the combined retrofitting scheme consist of solar thermal system and window renovation was also proposed and explored. As a result the energy performance of the single-family home would satisfy the nearly-zero energy building requirements and thermal comfort could be maintained at an acceptable level.
47

Data-driven retrofitting strategy for buildings in Minneberg, Stockholm

NOHRA, MARC January 2020 (has links)
Complying with the Paris agreements requires substantial efforts in the building sector, and especially within the existing building stock which is responsible for a considerable amount of emissions and energy consumption. This master thesis focuses on the residential district of Minneberg, located in the west of Stockholm in Bromma. The urban building energy modelling (UBEM) approach is used to model the situation of the current district. This method uses real-life data provided by the district, as well as information found in energy performance certificates and in public databases. Based on that, a virtual archetype building representing the whole district is modelled and calibrated. Suitable energy-efficient solutions that can contribute to reducing the energy consumption are identified and applied in two different scenarios. The first scenario consists in retrofitting the current building stock, while the second represents the case where the building has to be designed from scratch today to comply with Boverket’s requirements on nearly zero-energy buildings ("New Minneberg" scenario). The aggregation of the results shows that the current district is already quite energy-efficient, with the installation of solar panels seeming to be the only economically viable retrofitting option. As for the "New Minneberg" scenario, it is possible to comply with the requirements and achieve a C-class building by reducing the primary energy consumption, but that comes at the expense of a higher actual energy consumption. / Att följa Parisavtalen kräver stora ansträngningar inom byggsektorn, och särskilt inom det befintliga byggnadsbeståndet som står för en betydande mängd växthusgasutsläpp och energianvändning. Examensarbetet fokuserar på det svenska bostadsområdet av Minneberg, som ligger i västra Stockholm i Bromma. UBEM-metoden (urban building energy modelling) används för att modellera situationen i det nuvarande distriktet. Metoden använder verkliga data från fastighetsområdet, liksom information som finns i energideklarationer och offentliga databaser. Därefter modelleras och kalibreras en virtuell arketypsbyggnad som representerar hela distriktet. Lämpliga energieffektiva lösningar som kan bidra till att minska energiförbrukningen identifieras och tillämpas i två olika scenarier. Det första scenariot består i renovering av det nuvarande byggnadsbeståndet, medan det andra representerar fallet om byggnaden hade designats från grunden idag, för att uppfylla Boverkets krav på nollenergihus ("New Minneberg" scenario). Resultaten visar att det nuvarande distriktet redan är ganska energieffektivt, där installation av solpaneler verkar vara den enda ekonomiskt lönsamma åtgärden. Gällande "New Minneberg" scenariot är det möjligt att uppfylla kraven och uppnå en C-klass byggnad genom att minska primärenergitalet, men det resulterar i en högre verklig energiförbrukning.
48

Neutral lightweight engineering: a holistic approach towards sustainability driven engineering

Kupfer, Robert, Schilling, Levin, Spitzer, Sebastian, Zichner, Marco, Gude, Maik 30 May 2024 (has links)
The continuously growing social and political pressure to provide sustainable products is forcing also the lightweight industry to rethink current development and manufacturing processes. While established development approaches in lightweight engineering mainly focus on technical and economical product requirements they usually do not consider sustainability criteria. To address these challenges, a new class within the lightweight disciplines is proposed—the Neutral Lightweight Engineering. Its basic goal is to integrate sustainability criteria in all decisions along the development chain of a lightweight component. The decision makers in lightweight engineering thereby have to consider the whole life cycle of a product system from material sourcing to end-of-life part management. To implement this idea, advanced development methods are necessary, using established and emerging materials as well as efficient production and end-of-life strategies. This concept article introduces the idea of Neutral Lightweight Engineering and exemplary highlights some of its aspects before the background of scientific literature.
49

Ολιστική ενεργειακή θεώρηση κτιρίων

Σακκά, Αγγελική 06 November 2014 (has links)
Στις χώρες της Ευρωπαϊκής Ένωσης ο κτιριακός τομέας απορροφά περίπου το 40% της συνολικής ενεργειακής κατανάλωσης, γεγονός που καθιστά απαραίτητο το λειτουργικό και φιλικό προς το περιβάλλον σχεδιασμό των κτιρίων, παράλληλα με τον περιορισμό των συνολικών ενεργειακών αναγκών τους για την εξοικονόμηση ενέργειας. Όσον αφορά τα ήδη υπάρχοντα κτίρια, μπορούν να γίνουν διάφορες παρεμβάσεις ώστε να επιτευχθεί η μέγιστη δυνατή εξοικονόμηση ενέργειας. Από την άλλη, η Ε.Ε.,στα πλαίσια της βιώσιμης ανάπτυξης και της προστασίας του περιβάλλοντος, έχει θέσει ως στόχο για το 2020 τα καινούρια κτίρια να είναι μηδενικών εκπομπών διοξειδίου του άνθρακα. Για την υλοποίηση του στόχου αυτού, είναι αναγκαίος ο σχεδιασμός των κτιρίων σύμφωνα με τις αρχές της βιοκλιματικής αρχιτεκτονικής, για την ελαχιστοποίηση των ενεργειακών τους αναγκών αλλά και η εφαρμογή συστημάτων Ανανεώσιμων Πηγών Ενέργειας για την παραγωγή θερμικής και ηλεκτρικής ενέργειας και την ελαχιστοποίηση έτσι των εκπομπών CO2 στην ατμόσφαιρα από τα ορυκτά καύσιμα. Στην παρούσα διπλωματική εργασία, αναπτύσσονται στρατηγικές που αποσκοπούν στην αρμονική ένταξη των κτιρίων στο φυσικό περιβάλλον, παρουσιάζονται τα θέματα εξοικονόμησης ενέργειας στα κτίρια, διατυπώνονται οι βασικές παράμετροι για την επίτευξη ολιστικής ενεργειακής κάλυψης των κτιρίων και την προετοιμασία του επόμενου βήματος σχετικά με την ενέργεια στα κτίρια για το έτος 2020 και δίνονται νέες τεχνολογικές λύσεις που αναπτύχθηκαν στο εργαστήριο ηλιακής ενέργειας, με σκοπό την βέλτιστη αξιοποίηση της ηλιακής ενέργειας και των άλλων ΑΠΕ στα κτίρια. Στα πλαίσια της πλήρους κάλυψης των κτιριακών ενεργειακών αναγκών από ΑΠΕ και της προώθησης των κτιρίων σχεδόν μηδενικής κατανάλωσης από συμβατικές ενεργειακές πηγές, μελετάται πειραματικά η συμβολή των φωτοβολταϊκών σε δυσμενή κλίση και προσανατολισμό. Εξετάζεται η συνεισφορά διάχυτων ανακλαστήρων στην ενεργειακή τους απόδοση, η επίδραση του υλικού της θερμομόνωσης και του περιορισμού των θερμικών απωλειών. Τέλος, εξετάζεται η αξιοποίηση κάθε τμήματος του κτιρίου που μπορεί να έχει θετική συμβολή στο ενεργειακό θέμα. Έτσι προτείνονται τρόποι τοποθέτησης φωτοβολταϊκών σε οριζόντιες και επικλινείς στέγες και στις προσόψεις των κτιρίων, με προσθήκη ανακλαστήρα όπου είναι δυνατό, που μπορούν να συνεισφέρουν στην επίτευξη μηδενικού ενεργειακού ισοζυγίου στα κτίρια. / In the countries of the European Union the building sector accounts for about 40% of the total energy consumption, so it is necessary that the buildings should be designed in a functional and environmentally-friendly way, in addition to the minimization of of the total energy needs to achieve energy savings. As for the existing buildings, they should be renovated so that maximum energy savings is achieved. On the other hand, the EU’s target for 2020 is that new buildings must be of zero carbon dioxide emissions. For the implementation of this goal, buildings should be designed according to the principles of bioclimatic architecture to minimize energy needs, but also systems of Renewable Energy Sources should be applied to produce thermal energy and electricity, in order to minimize carbon dioxide emissions from fossil fuels. In the present thesis, strategies aiming to harmonic integration of buildings in the natural environment are developed, holistic energy saving aspects for buildings are presented, aspects regarding the next step to the target for 2020 are given, and some new designs of building integrated RES, investigated at the Solar Energy Laboratory, are suggested. Approaching the holistic contribution of the renewable energy sources (RES) to buildings for total cover of their energy demand, and the achievement of nearly zero energy buildings, the contribution of photovoltaics in disadvantageous inclination and azimuth angle is experimentally studied. The contribution of diffuse reflectors to pV’s energy efficiency, the impact of thermal insulation materials and the impact of limitating the thermal losses to PV’s operation, are studied as well. Furthermore, the use of every single part of the building in order to contribute to its energy supply, is considered. Designs for photovoltaic integration on horizontal and inclined roofs and facades are suggested, combined with booster reflector if possible, aiming to achieve zero energy balance of buildings.
50

Consequences of Insect Flight Loss for Molecular Evolutionary Rates and Diversification

Mitterboeck, T. Fatima 25 May 2012 (has links)
This thesis investigates the molecular evolutionary and macroevolutionary consequences of flight loss in insects. Chapter 2 tests the hypothesis that flightless groups have smaller effective population sizes than related flighted groups, expected to result in a consistent pattern of increased non-synonymous to synonymous ratios in flightless lineages due to the greater effect of genetic drift in smaller populations. Chapter 3 tests the hypothesis that reduced dispersal and species-level traits such as range size associated with flightlessness increase extinction rates, which over the long term will counteract increased speciation rates in flightless lineages, leading to lower net diversification. The wide-spread loss of flight in insects has led to increased molecular evolutionary rates and is associated with decreased long-term net diversification. I demonstrate that the fundamental trait of dispersal ability has shaped two forms of diversity—molecular and species—in the largest group of animals, and that microevolutionary and macroevolutionary patterns do not necessarily mirror each other. / Generously funded by NSERC with a Canada Graduate Scholarship and the Government of Ontario with an Ontario Graduate Scholarship to T. Fatima Mitterboeck; NSERC with a Discovery Grant to Dr. Sarah J. Adamowicz

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