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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.
71

Mobilní asistent pro cestování MHD / Mobile Public Transportation Assistant

Tůma, Jan January 2017 (has links)
This thesis is a documentation covering complete design and implementation of a mobile public transportation assistant for Brno. The resulting solution consists of a mobile application and a server part. The mobile application allow user with actual position of public transport vehicles and positon of smart device navigate and determine optimal route. The server part includes web service for client-server communication.
72

Inovativní finanční nástroje: Alternativa k tradičním dotacím / Innovative Financial Instruments: An alternative to traditional grants

Jelínek, Tomáš January 2016 (has links)
Innovative financial instruments in the Czech Republic and their hypothetical use in the field of energy efficiency are analysed and assessed in this thesis. We address lim- ited awareness about multiple benefits of energy efficiency improvements and also emerging innovative financial instruments that are promoted by the European Com- mission as a way to multiply impacts of limited public budgets. Then we identify a suitable segment, Czech residential housing stock and public support of insulation, and compare several forms of possible public support in this field. As the main driver of space heating costs, we predict the future development of heat prices, and assess po- tential energy savings resulting from renovations. Finally, we assess and also simulate the potential of such an initiative and identify four suitable settings of the innovative financial instrument for a majority of stakeholders. Our findings support an idea that this innovative financial instrument offers a valuable alternative to traditional grants. It also suggests that such an initiative can be interesting for a private sector as well as a public sector, with benefits to public budgets, equity investors, households and many other stakeholders. Moreover, this initiative can be sustainable in the long run. JEL Classification G23,...
73

Seismic Retrofit of Concrete Columns by Transverse Prestressing

Sabri, Amirreza 09 September 2013 (has links)
Performance of buildings and bridges during past earthquakes has indicated that many of these structures are vulnerable to seismic damage and structural collapse. The deficiencies in pre-1970s design codes have resulted in poor performance of reinforced concrete structures during seismic excitations. The Richter Magnitude 6.6 - 1971 San Fernando Earthquake raised awareness for seismic retrofit needs of existing buildings for the first time. The majority of deficiencies of vulnerable concrete columns can be overcome through seismic retrofits that involve additional transverse reinforcement. This can be done either by providing reinforced concrete, steel, or fibre-reinforced polymer (FRP) jackets around existing columns; or by applying transverse prestressing to columns (RetroBelt System). The research project presented in this thesis involves a seismic retrofit methodology for seismically deficient building and bridge columns, utilizing the use of high-strength packaging straps as external reinforcement for transverse prestressing. The emphasis in the project is placed on experimental research. Three seismically deficient full-size reinforced concrete columns, with a circular, a square and a rectangular cross- section, either critical in shear or flexure, were designed, built and tested under simulated seismic loading. The results indicate that external prestressing of columns in transverse direction with high-strength steel straps improves ductility and energy dissipation capacity of seismically deficient columns. They further indicate that current analytical techniques can be used to predict the force-displacement relationships of columns. A design approach is presented for the retrofit methodology investigated.
74

Eficiência energética em edificações - estudo de caso tribunal de justiça de São Paulo / Buildings energy efficiency – case study tribunal de justiça de São Paulo

Ferrador Filho, Antonio Luiz 23 February 2017 (has links)
Submitted by Nadir Basilio (nadirsb@uninove.br) on 2017-05-22T19:18:36Z No. of bitstreams: 1 Antonio Luiz Ferrador Filho.pdf: 5915578 bytes, checksum: 551fba401297a5d3da42829909edc17d (MD5) / Made available in DSpace on 2017-05-22T19:18:36Z (GMT). No. of bitstreams: 1 Antonio Luiz Ferrador Filho.pdf: 5915578 bytes, checksum: 551fba401297a5d3da42829909edc17d (MD5) Previous issue date: 2017-02-23 / The building sector is one of the largest consumers of energy in global terms, hence the importance of search for energy efficiency in this Field. According to the buildings life cycle, it is in the operational phase in which the highest energy consumption occurs. This research aimed to identify opportunities for energy efficiency improvements in a public, existing and operational Tribunal de Justiça de São Paulo building. The applied method was the case study. Data were collected in unstructured interviews and technical visits at the site, as well as related documentation examination. The data were analyzed by the PROCEL-Edifica prescriptive method, obtaining energy classification for the three characteristics of the building: the envelope got the label C, the illumination got label C and the conditioning of air got label B. The building general classification obtained was label C. The implications of this work for practice are in indicating potential improvements in the building's facilities to increase energy efficiency and in the analysis of potential and limitations for the study replication in other buildings. Some of the potential improvements identified were: change of fluorescent lamps to LEDs, change in the rooms lighting circuit, use of polarized films in the building’s glass, improvement in the vertical and horizontal shading of tower façades by using elements that reduce the direct incidence of sunlight. A basic investment payback period analysis for some improvements was conducted, as a examples to a action priorities definition. The method used can serve as a basis of a systematic to be replicated in other TJ/SP buildings. This study can contribute to the enhancement of the TJ/SP Sustainable Logistics Plan, in its line of buildings energy efficiency. In general, the prescriptive method accepted by PROCEL-Edifica criteria is indicated for this study’s replication in other buildings of the TJ/SP, due to the agility to change parameters theoretically and obtain results that may guide the introduction of energetic efficiency improvement measures. However, the “envelope” dimension evaluation has a more complex replication and possibly will require trained technicians participation when analyzing other buildings. / O setor de edificações é um dos maiores consumidores de energia em termos globais, daí a importância da busca da eficiência energética neste campo. Levando em conta o ciclo de vida das construções, é na sua fase operacional em que ocorre o maior consumo de energia. Esta pesquisa buscou identificar oportunidades de melhorias em eficiência energética em um edifício do Tribunal de Justiça de São Paulo, público, existente e operacional. O método aplicado foi o estudo de caso. Os dados foram coletados em entrevistas não estruturadas e visitas técnicas no local, além do exame de documentação relacionada. Foi feita a análise dos dados pelo método prescritivo do PROCEL-Edifica, obtendo classificação energética para as três características do prédio: a envoltória foi caracterizada com a etiqueta C, a iluminação a etiqueta C e o condicionamento de ar a etiqueta B. A classificação geral do prédio obtida foi etiqueta C. As implicações deste trabalho para a prática estão na indicação de potenciais melhorias nas instalações do prédio para aumento da eficiência energética e na análise de potencial e limitações para a replicação do estudo em outros prédios. Algumas das potenciais melhorias identificadas foram: mudança de lâmpadas fluorescentes para LED, alteração no circuito de iluminação de salas, uso de filmes polarizados nos vidros, melhoria no sombreamento vertical e horizontal das fachadas da torre pela utilização de elementos que diminuam a incidência direta da luz solar, como brises. Uma análise básica de tempo de retorno de investimento para algumas melhorias foi feito, demonstrando possível priorização de ações. O método usado pode servir como base de uma sistemática a ser replicada em outros edifícios do TJ/SP. Esse estudo visa contribuir para o aperfeiçoamento do Plano de Logística Sustentável do TJ/SP, na sua linha de eficiência energética de edifícios. No geral o método prescritivo aceito pelos critérios do PROCEL-Edifica é indicado para replicação do estudo em outros prédios do TJ/SP, devido a agilidade para alterar parâmetros teoricamente e obter resultados que orientem a introdução de medidas de melhorias da eficiência energética. No entanto, a avaliação da dimensão "envoltória" tem uma replicação mais complexa e possivelmente exigirá a participação de técnicos treinados quando da análise de outros edifícios.
75

Seismic Retrofit of Concrete Columns by Transverse Prestressing

Sabri, Amirreza January 2013 (has links)
Performance of buildings and bridges during past earthquakes has indicated that many of these structures are vulnerable to seismic damage and structural collapse. The deficiencies in pre-1970s design codes have resulted in poor performance of reinforced concrete structures during seismic excitations. The Richter Magnitude 6.6 - 1971 San Fernando Earthquake raised awareness for seismic retrofit needs of existing buildings for the first time. The majority of deficiencies of vulnerable concrete columns can be overcome through seismic retrofits that involve additional transverse reinforcement. This can be done either by providing reinforced concrete, steel, or fibre-reinforced polymer (FRP) jackets around existing columns; or by applying transverse prestressing to columns (RetroBelt System). The research project presented in this thesis involves a seismic retrofit methodology for seismically deficient building and bridge columns, utilizing the use of high-strength packaging straps as external reinforcement for transverse prestressing. The emphasis in the project is placed on experimental research. Three seismically deficient full-size reinforced concrete columns, with a circular, a square and a rectangular cross- section, either critical in shear or flexure, were designed, built and tested under simulated seismic loading. The results indicate that external prestressing of columns in transverse direction with high-strength steel straps improves ductility and energy dissipation capacity of seismically deficient columns. They further indicate that current analytical techniques can be used to predict the force-displacement relationships of columns. A design approach is presented for the retrofit methodology investigated.
76

[en] EVALUATION OF INVESTMENTS IN RETROFIT OF WIND FARMS BY REAL OPTIONS / [pt] AVALIAÇÃO DE INVESTIMENTOS EM RETROFIT DE PARQUES EÓLICOS POR OPÇÕES REAIS

ANA MARIA ZUNIGA VELASCO 08 August 2017 (has links)
[pt] Com o objetivo de reduzir o efeito estufa e atender a alta demanda de energia elétrica, muitos países desenvolvidos e emergentes têm optado pelo uso de energias essencialmente de origem renovável, incluindo energia eólica, biomassa e solar fotovoltaica. Para determinar a viabilidade econômica dos projetos de energias renováveis é necessário capturar as variáveis de maior interesse. As opções reais ao considerar a dinâmica e incertezas, típicas dos mercados de eletricidade, surgem como uma alternativa para a tomada de decisões neste tipo de projetos. Este trabalho aplica a técnica tradicional de avaliação de projetos através do fluxo de caixa descontado (FCD) e a teoria de opções reais (TOR) para avaliação de um parque eólico. A flexibilidade foi incluída ao considerar a opção de fazer um investimento em retrofit para atualizar a tecnologia das turbinas eólicas e estender o contrato de operação. A opção real analisada é análoga a uma opção de compra europeia, seu valor é calculado através de uma árvore binomial recombinante com barreira no preço da energia eólica, principal fonte de incerteza do modelo. Realizaram-se análises de sensibilidade para avaliar o comportamento do preço da opção frente às mudanças em alguns parâmetros do modelo. Conclui-se a viabilidade econômica de estender a operação do parque eólico através de um investimento em retrofit, utilizando a TOR, uma vez que o seu valor é muito superior frente ao calculado pelo FCD, apesar do valor da opção ter uma forte correlação com o limite da barreira e a volatilidade do preço. / [en] In order to reduce the greenhouse effect and meet the high demand of electricity, many developed and emerging countries have opted for the use of renewable energies, for example, wind energy, biomass and solar photovoltaic. To determine the economic viability of renewable energy projects it is necessary to capture the most relevant variables that suggest greater interest. Real options allows to consider the dynamic and uncertainties present in the power markets, therefore it is an attractive tool for decision-making in this kind of markets. In this work we apply the traditional technique of project evaluation, the discounted cash flow (DCF), as well as the real real options theory (ROT) for the financial evaluation of a wind farm. The flexibility is the option of making a retrofit investment that allows upgrading the wind turbines technology in order to extend the operating contract. The real option analyzed is analogous to a european call option and its value was calculated through a recombinant binomial tree with barrier in the wind energy price, considered the main source of uncertainty in the model. Sensitivity analyzes were performed to assess the option price behavior when some parameters of the model change. We finally conclude for the economic viability of extending the operation of the wind farm through an investment in retrofit, using the ROT, since its value is much higher than the calculated by the DCF, even though the option value is strongly dependent on the barrier and the volatility of electricity prices.
77

Innovation and experts / An economic analysis on knowledge-intensive business services and energy efficiency consultants

Feser, Daniel 25 February 2016 (has links)
No description available.
78

The Nonlinear Dynamics Involved in the Seismic Assessment and Retrofit of Reinforced Concrete Buildings

Quintana-Gallo, Patricio Ignacio January 2014 (has links)
Seismically vulnerable buildings constitute a major problem for the safety of human beings. In many parts of the world, reinforced concrete (RC) frame buildings designed and constructed with substandard detailing, no consideration of capacity design principles, and improper or no inclusion of the seismic actions, have been identified. Amongst those vulnerable building, one particular typology representative of the construction practice of the years previous to the 1970’s, that most likely represents the worst case scenario, has been widely investigated in the past. The deficiencies of that building typology are related to non-ductile detailing in beam column joints such as the use of plain round bars, the lack of stirrups inside the joint around the longitudinal reinforcement of the column, the use of 180° end hooks in the beams, the use of lap splices in potential ‘plastic hinge’ regions, and substandard quality of the materials. That type of detailing and the lack of a capacity design philosophy create a very fragile fuse in the structure where brittle inelastic behaviour is expected to occur, which is the panel zone region of exterior beam column joints. The non-ductile typology described above was extensively investigated at the University of Canterbury in the context of the project ‘Retrofit Solutions for New Zealand Multi-Storey Buildings’ (2004-2011), founded by the ‘Foundation for Research, Science and Technology’ Tūāpapa Rangahau Pūtaiao. The experimental campaign prior to the research carried out by the author consisted of quasi-static tests of beam column joint subassemblies subjected to lateral loading regime, with constant and varying axial load in the column. Most of those specimens were representative of a plane 2D frame (knee joint), while others represented a portion of a space 3D frame (corner joints), and only few of them had a floor slab, transverse beams, and lap splices. Using those experiments, several feasible, cost-effective, and non-invasive retrofit techniques were developed, improved, and refined. Nevertheless, the slow motion nature of those experiments did not take into account the dynamical component inherent to earthquake related problems. Amongst the set of techniques investigated, the use of FRP layers for strengthening beam column joints is of particular interest due to its versatility and the momentum that its use has gained in the current state of the practice. That particular retrofit technique was previously used to develop a strengthening scheme suitable for plane 2D and space 3D corner beam column joints, but lacking of floor slabs. In addition, a similar scheme was not developed for exterior joints of internal frames, referred here as ‘cruciform’. In this research a 2/5 scale RC frame model building comprising of two frames in parallel (external and internal) joined together by means of floor slabs and transverse beams, with non-ductile characteristics identical to those of the specimens investigated previously by others, and also including lap splices, was developed. In order to investigate the dynamic response of that building, a series of shake table tests with different ground motions were performed. After the first series of tests, the specimen was modified by connecting the spliced reinforcement in the columns in order to capture a different failure mode. Ground motions recorded during seismic events that occurred during the initial period of the experimental campaign (2010) were used in the subsequent experiments. The hierarchy of strengths and sequence of events in the panel zone region were evaluated in an extended version of the bending moment-axial load (M-N) performance domain developed by others. That extension was required due to the asymmetry in the beam cross section introduced by the floor slab. In addition, the effect of the torsion resistance provided by the spandrel (transverse beam) was included. In order to upgrade the brittle and unstable performance of the as-built/repaired specimen, a practical and suitable ad-hoc FRP retrofit intervention was developed, following a partial retrofit strategy that aimed to strengthen exterior beam column joints only (corner and cruciform). The ability of the new FRP scheme to revert the sequence of events in the panel zone region was evaluated using the extended version of the M-N performance domain as well as the guidelines for strengthening plane joints developed by others. Weakening of the floor slab in a novel configuration was also incorporated with the purpose of reducing the flexural capacity of the beam under negative bending moment (slab in tension), enabling the damage relocation from the joint into the beam. The efficacy of the developed retrofit intervention in upgrading the seismic performance of the as-built specimen was investigated using shake table tests with the input motions used in the experiments of the as-built/repaired specimen. Numerical work aimed to predict the response of the model building during the most relevant shake table tests was carried out. By using a simple numerical model with concentrated plasticity elements constructed in Ruaumoko2D, the results of blind and post-experimental predictions of the response of the specimen were addressed. Differences in the predicted response of the building using the nominal and the actual recorded motions of the shake table were investigated. The dependence of the accuracy of the numerical predictions on the assumed values of the parameters that control the hysteresis rules of key structural members was reviewed. During the execution of the experimental campaign part of this thesis, two major earthquakes affected the central part of Chile (27 of February 2010 Maule earthquake) and the Canterbury region in New Zealand (22 February 2011 Canterbury earthquake), respectively. As the author had the opportunity to experience those events and investigate their consequences in structures, the observations related to non-ductile detailing and drawbacks in the state of the practice related to reinforced concrete walls was also addressed in this research, resulting in preliminary recommendations for the refinement of current seismic code provisions and assessment guidelines. The investigations of the ground motions recorded during those and other earthquakes were used to review the procedures related to the input motions used for nonlinear dynamic analysis of buildings as required by most of the current code provisions. Inelastic displacement spectra were constructed using ground motions recorded during the earthquakes mentioned above, in order to investigate the adequacy of modification factors used to obtain reduced design spectra from elastic counterparts. Finally a simplified assessment procedure for RC walls that incorporates capacity compatible spectral demands is proposed.
79

Examining English planning as a barrier to the thermal improvement of conservation properties

Friedman, Kayla Simone January 2015 (has links)
This dissertation examines why planning is perceived as a barrier to the thermal improvement of conservation properties, and considers ways in which this might be addressed. The focus on thermal improvement is derived from a survey of UK scenario literature for energy management up to 2050. A further examination of the literature finds that conservation properties are particularly in need of thermal improvement; and barriers to thermal improvement are identified. A gap in the academic knowledge is found that identifies planning as a perceived barrier, but that there is no investigation of this widely held perception. The research question is therefore developed as, 'Why is English planning perceived as a barrier to the thermal improvement of conservation properties and how can it be addressed?' The dissertation methodology uses a pragmatic mixed-methods approach and research design. The first phase of the research examines 'Why planning is perceived as a barrier', by using surveys and interviews to gather evidence of the experiences and opinions of the multiple users of planning for conservation projects. Through this work, a lack of consistency and reliability in English planning is identified. The data suggests this may be due to the discretionary and fragmented nature of the English planning system which requires local authorities to interpret national policies and develop local plans and guidance. This results in local decision-making, which may not be consistent. Additionally, the research finds a perceived lack of strong national policy and guidance. This perceived lack of consistency and reliability in the application of planning is selected as the basis for validation phase of the dissertation research findings. The validation research seeks to test the perception of a lack of consistency and reliability through a Comparative Information Quality assessment adapted and developed from the discipline of Information Management. Online planning guidance for conservation projects provided by 13 London Councils is compared. The method confirms and highlights areas of inconsistency across the Councils' planning guidance. By identifying a number of areas of inconsistency, and by providing a tool that could help to ensure that policy is delivered consistently at the local level, this component of the research addresses the second part of the research question, 'How can the planning barrier be addressed?'. In conclusion, the dissertation suggests that planning is perceived as a barrier due to a lack of consistency and reliability in the planning process. Inconsistencies are identified and a recommendation is made for how these might be reduced.
80

Submerged attached-growth reactors as lagoon retrofits for cold-weather ammonia removal

Mattson, Rebecca Ruth 01 May 2018 (has links)
Small towns that operate wastewater treatment lagoons struggle to meet ammonia limits in cold weather. Here we report the performance of a lagoon, retrofitted with submerged attached-growth reactors (SAGRsTM), to provide insight on ammonia effluent compliance and optimal SAGR sizing as functions of water temperature. The lagoon-SAGR water resource recovery facility (WRRF) removed 95% of incoming ammonia with 94% attributable to the SAGRs. The high treatment capacity of the two primary SAGRs, evidenced by nearly continuous dissolved oxygen saturation and exceedingly high ammonia removals, suggested the two secondary SAGRs were essentially unnecessary and that all four SAGRs should be reduced in size. Furthermore, without the secondary SAGRs, the primary SAGR effluent would have exceeded the permitted ammonia discharge limit only four times in the 2.5 year study. At its current size, the lagoon-SAGR WRRF never exceeded permitted ammonia limits, but size reductions should be used for future retrofits. To further understand cold-weather ammonia removal in the lagoon-SAGR WRRF, we investigated the effect of increased ammonia loading on biomass and the effect of biofilms on microbial abundance. When ammonia loading to the SAGRs was increased in the fall, the lagoon-SAGR WRRF never exceeded its ammonia permit limit, the kinetic coefficients were maintained (0.5-0.8 d-1) and the NH3 removal rates improved (0.25 kg d-1 in baseline loading to 0.45 kg d-1) despite a large temperature decrease (25 °C to < 16 °C). In the biofilm, ammonia-oxidizing archaea abundance was 10 times greater than the ammonia-oxidizing bacteria abundance suggesting the potential importance of ammonia oxidizing archaea in biofilm mediated systems. Additionally, the ammonia and nitrite transforming microbes in the SAGRs had a diverse range of dissolved oxygen affinities and were more abundant in the biofilm in comparison to the wastewater. Anaerobic ammonium-oxidizing bacteria were abundant in the biofilm even though the film constantly interacted with high dissolved oxygen. We found that two components of a successful lagoon-SAGR WRRF were increased biomass in the SAGRs before cold-weather due to elevated ammonia loading and diverse oxygen affinities in the microbes related to ammonia removal.

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