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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.
1

Towards a spatial energy model : a theoretical comparison of accessibility and energy-use in regional settlement patterns

Rickaby, P. January 1985 (has links)
The research reported is a theoretical investigation of the interaction of land-use and transport in relation to the use of energy. Of particular interest is the relationship between the spatial arrangement of settlements and the use of energy within them for both transport and building services. The literature of scenarios of energy futures is reviewed, and three scenarios of future constraints on regional planning are adopted. The adopted scenarios emphasise constraints imposed by energy policy and the availability of fuels; they form the background to the comparison of a number of theoretical regional settlement patterns, in terms of their implications for land-use and their potential for fuel-conservation. A study of an existing regional settlement pattern is used in combination with published land-use data as the basis of a configurational model. This model is intended to characterise the real pattern spatially, quantitatively and in a manner suitable for experimental manipulation. The model encompasses the pattern of developed land (disaggregated by uses), the shape of the transport network, and the intensity of development (in terms of population and floorspace). A review is then made of published proposals for energy-efficient settlements, which are found to include concentrated, dispersed, nucleated and linear patterns. Five modified versions of the regional configurational model are then constructed in order to characterise the range of realistic possibilities for future regional form which might result from the fuel-conservation policies inherent in the proposals reviewed. The five regional configurations and the original pattern are then compared by means of a specially-developed land-use transport and energy-evaluation model. The comparison is made in terms of the accessibility of the population in each pattern to employment and services (measured 'biy the model as "benefits"), and. in terms of the use of fuel in both transport and domestic space heating. Fuel use in transport is related to modal split and vehicle speed; fuel use in homes is related to dwelling size and location. Parametric calibration of the land-use and transport models allows the comparison of the patterns to be repeated in the context of each of the three adopted energy scenarios, taking into account changes in travelling behaviour, vehicle efficiencies, and building services technologies. The results of the comparison are discussed and assessed in terms of their implications for long-term strategic planning policy.
2

Avaliação energética de dois sistemas de produção de milho

Bernardi, Lorena de Moraes 22 August 2008 (has links)
Made available in DSpace on 2014-08-20T14:33:07Z (GMT). No. of bitstreams: 1 Dissertacao_ Lorena_ Moraes_ Bernardi.pdf: 2986902 bytes, checksum: b4621b4cf077e4399295aa2882c48ccc (MD5) Previous issue date: 2008-08-22 / Consumption of energy in a system of production is one of the most worrying things in agricultural activity. Accordingly, the calculation of the energy balance is one of the most important tools when you want to assess the sustainability of agroecosystems. This study aimed to evaluate the consumption and production of energy in two systems of production of corn, one of ecological base and other conventional, developed in two agricultural properties, both located in Pelotas/RS. Questionnaires modified in Marchioro (1985), were applied to farmers, with the aim of characterizing the production units, the composition of families, the hours devoted to each operation and management practices and types and quantity of inputs used. By the existing scientific literature, the equivalent energy were identified that are present in the stages of production processes, which led to measure the consumption (input), energy (human / animal activity, agricultural chemicals, fuel ...) and the energy produced (output) for biomass derived from their systems, which was obtained through the collection of a sample of the population of corn plants chosen at random, which after passing through processes of drying and weighing in laboratory provided data representative of the total production of biomass in cultivated areas, data which were finally converted into equivalent energy production. The entrances and exits of energy in both systems were related and led their respective energy balances. The total consumption of energy in 1 (one) hectare of the ecological base system of production (1,38 MJ) is lower than in 1 (one) hectare of conventional system (5.789,10 MJ) and energy production in the same area proved to be greater in the production system of ecological base (321.225,30 MJ) than in conventional (166.055,02 MJ). It was confirmed that the energy balance in the ecological base system of production (232,93) is most effective when compared to the conventional system (29,20). / O consumo de energia num sistema de produção é um dos aspectos mais preocupantes na atividade agrícola. Nesse sentido, o cálculo do balanço energético se constitui numa das mais importantes ferramentas quando se quer avaliar a sustentabilidade de agroecossistemas. O presente trabalho teve como objetivo avaliar o consumo e a produção de energia em dois sistemas de produção de milho, um de base ecológica e outro convencional, desenvolvidos em duas propriedades agrícolas, ambas localizadas no município de Pelotas/RS. Questionários modificados de Marchioro (1985), foram aplicados aos agricultores, com a finalidade de caracterizar as unidades de produção, a composição das famílias, as horas dedicadas à cada operação e práticas de manejo e tipos e quantidade de insumos utilizados. Com embasamento na literatura científica existente, foram identificados os equivalentes energéticos que se fazem presentes nas etapas dos processos de produção, os quais permitiram mensurar o consumo (input) de energia (atividade humana/animal, agroquímicos, combustível...) e a energia produzida (output) pela biomassa oriunda dos respectivos sistemas, a qual foi obtida através da colheita de uma amostra da população de plantas de milho escolhidas ao acaso, que após passarem por processos de secagem e pesagem em laboratório forneceram dados representativos da produção total de biomassa nas áreas cultivadas, dados esses que foram por fim convertidos em equivalentes energéticos de produção. As entradas e saídas de energia em ambos os sistemas foram relacionadas e originaram seus respectivos balanços energéticos. O consumo de energia total em 1 (um) hectare do sistema de produção de base ecológica (1,38 MJ) é menor que em 1 (um) hectare do convencional (5.789,10 MJ) e a produção de energia na mesma área mostrou-se maior no sistema de produção de base ecológica (321.225,30 MJ) que no convencional (169.055,02 MJ). Confirmou-se que o balanço energético no sistema de produção de base ecológica (232,93) é mais eficiente se comparado ao convencional (29,20).
3

Energetické hodnocení budovy pro občanskou vybavenost obce / Energy evaluation of building for public facilities

Procházková, Adéla January 2016 (has links)
The aim of thesis is the energy evaluation of building for public facilities - kindergarten. From the beginning work deals with the analysis of a given topic, standard and legal regulations associated with the topic. This knowledge is further applied to a specific building. It follows by evaluation of the current state of the building, its systems, internal environment and analysis of measures leading to energy savings and ensuring the quality of the indoor environment of building. Work also deals with experimental measurements of selected parameters of the internal environment.
4

On The Importance of Light Source Classification in Indoor Light Energy Harvesting

Zhang, Ye January 2018 (has links)
Indoor light energy harvesting plays an important role in field of renewable energy. Indoor lighting condition is usually described by level of illumination. However, measured data alone does not by classification of different light sources, result is not representative. Energy harvesting system needs to be evaluated after classification to obtain more accurate value. This is also importance of different light source classification. In this thesis, a complete set of indoor light energy harvesting system is introduced, two models are proposed to evaluate energy, robustness is improved by mixing complex light condition during data collection. Main task of this thesis is to verify importance of indoor light classification. Main contribution of this thesis is to fill a gap in energy evaluation, and built a model with superior performance. In terms of collecting data, this thesis researches influence factor of data collection to ensure reliability of accuracy. This work can more accurately collect spectral under different light conditions. Finally, light energy is evaluated by classification of indoor light. This model is proven to be closer to true energy value under real condition. The result shows that classified data is more accurate than direct calculation of energy,it has a smaller error. In addition, performance of classifier model used in this thesis has been proven to be excellent, classifier model can still carry on high-accuracy classification when measurement data are not included in training data set. This makes it a low-cost alternative to measuring light condition without spectrometer.
5

Efficacité énergétique dans le calcul très haute performance : application à la tolérance aux pannes et à la diffusion de données / Energy efficiency in very high-performance computing : application to fault tolerance and data broadcasting

Diouri, Mohammed El Mehdi 27 September 2013 (has links)
Les infrastructures de calcul très haute performance ont connu une croissance rapide en particulier ces dernières années. Cette croissance a toujours été motivée par les besoins accrus en puissance de calcul qu'expriment les scientifiques dans divers domaines. Cependant, ces systèmes devenus de plus en plus larges constituent de gros consommateurs d'électricité et consomment déjà plusieurs mégawatts. Afin de consommer ''moins'' et ''mieux'', nous avons proposé un environnement logiciel qui d'une part, permet de choisir avant de pré-exécuter l'application, les versions de services applicatifs consommant le moins d'énergie, et qui d'autre part, repose sur une grille électrique intelligente pour planifier les réservations des ressources de calcul de ces infrastructures. Cet environnement, appelé SESAMES, a été adapté à deux services applicatifs indispensables au calcul très haute performance : la tolérance aux pannes et la diffusion de données. Des validations expérimentales ont montré que l'on peut réduire la consommation énergétique de chacun des deux services étudiés en s'appuyant sur les estimations énergétiques précises fournies par SESAMES pour n'importe quel contexte d'exécution et pour n'importe quelle plate-forme dotée de wattmètres. Notre méthodologie d'estimation repose sur une description du contexte d'exécution et sur une calibration de la plate-forme d'exécution basée sur la collecte de mesures énergétiques. Des simulations ont démontré que l'ordonnanceur multi-critères des réservations de ressources proposé dans SESAMES, permet de réduire à la fois la consommation énergétique, le coût financier et l'impact environnemental de ces réservations, tout en respectant les contraintes imposées par l'utilisateur et le fournisseur d'énergie. / High performance computing (HPC) infrastructures have experienced a rapid growth, particularly these last years. This growth has been driven by the increased need in terms of computational power expressed by scientists in various fields. However, their increasing size makes them important electricity consumers since they already consume several megawatts. In order to consume "less" and better", we proposed a framework which permits to choose the less consuming versions of the services before pre-executing the application. In addition, our framework relies on a smart grid in order to schedule resource reservations on these computing infrastructures. This framework, called SESAMES, is adapted to two services required in high performance computing: fault tolerance and data broadcasting. Experimental validations have shown that we can reduce the energy consumption of both services by relying on accurate energy estimations provided by SESAMES for any execution context and for any platform equipped with wattmeters. Our estimation methodology is based on a description of the execution context and on a platform calibration that consists of gathering energy measurements. Simulations have shown that the multi-criteria reservation scheduler proposed in SESAMES, simultaneously reduces the energy consumption, the financial cost and the environmental impact of these reservations, while respecting the constraints imposed by the user and the energy supplier.
6

Investigation of wireless sensor nodes with energy awareness for multichannel signal measurement

Zhu, Zhenhuan January 2015 (has links)
Wireless Sensor Networks (WSNets), consisting of a lot of Wireless Sensor Nodes (WSNs), play an important role in structural health and machine condition monitoring. But the WSNs provided by the current market cannot meet the diversity of application requirements because they have limited functions, unreliable node performance, high node cost, high system redundancy, and short node lifespan. The aim of the research is to design the architecture of a WSN with low power consumption and node cost, which can be dynamically configured according to application requirements for structural health and machine condition monitoring. This research investigates the improvement of node performance and reliability through the new design methodologies and the extension of node lifespan by interfacing energy harvesters and implementing node power management. The main contributions of the research are presented from the following aspects:1. Model development of node architecture for application diversityThe merits of model include: (1) The proposed node architecture can be dynamically configured in terms of application requirements for reducing system redundancy, power consumption and cost; (2) It supports multichannel signal measurement with the synchronous and asynchronous signal sampling modules and three interface circuits; (3)The model parameters can be calculated; (4) As the model is based on discrete electronic components, it can be implemented by using Components-Off-The-Shelf (COTS).2. A novel pipeline design of the built-in ADC inside a microprocessorThe merit of proposed pipeline solution lies in that the sampling time of the built-in ADCs is reduced to one third of the original value, when the ADC operates in sequence sampling mode based on multichannel signal measurement.3. Self-adjusting measurement of sampled signal amplitude This work provides a novel method to avoid the distortion of sampled signals even though the environmental signal changes randomly and over the sampling range of the node ADC. The proposed method can be implemented with four different solutions.4. Interface design to support energy harvesting The proposed interface will allow to: (1) collect the paroxysmal ambient energy as more as possible; (2) store energy to a distribution super-capacitor array; (3) harvest electrical energy at high voltage using piezoelectric materials without any transformer; (4) support the diversity of energy transducers; and (5) perform with high conversion efficiency.5. A new network task scheduling model for node wireless transceiver The model allows to: (1) calculate node power consumption according to network task scheduling; (2) obtain the optimal policy for scheduling network task.6. A new work-flow model for a WSN The model provides an easy way to (1) calculate node power consumption according to the work flow inside a WSN; (2) take fully advantage of the power modes of node electronic components rather than outside factors; (3) improve effectively node design.
7

Energetické hodnocení krasobruslařské haly / Energy Evaluation of the Figure Skating Hall

Šicová, Pavlína January 2015 (has links)
The diploma thesis contains an energy audit of the figure skating hall. In the first part I focused on the analysis of the topic, fire regulations and laws relating to given theme, recent technical, theoretical and experimental solutions in practice. In the next part, I compiled the of building energy audit of building, including its mandatory annexes. In the last part, I presented the results of measurements in the evaluated object.
8

Estudo analítico, térmico e energético do pinhão manso (Jatropha Curcas l.) como matéria-prima para a produção de biocombustíveis

Souza, Cristiane Daliassi Ramos de 10 November 2012 (has links)
Submitted by Lúcia Brandão (lucia.elaine@live.com) on 2015-07-15T16:05:00Z No. of bitstreams: 1 Tese - Cristiane Daliassi Ramos de Souza.pdf: 2429333 bytes, checksum: 3abea0012ee786e4320f226b2f591475 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-20T15:48:37Z (GMT) No. of bitstreams: 1 Tese - Cristiane Daliassi Ramos de Souza.pdf: 2429333 bytes, checksum: 3abea0012ee786e4320f226b2f591475 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-20T15:54:41Z (GMT) No. of bitstreams: 1 Tese - Cristiane Daliassi Ramos de Souza.pdf: 2429333 bytes, checksum: 3abea0012ee786e4320f226b2f591475 (MD5) / Made available in DSpace on 2015-07-20T15:54:42Z (GMT). No. of bitstreams: 1 Tese - Cristiane Daliassi Ramos de Souza.pdf: 2429333 bytes, checksum: 3abea0012ee786e4320f226b2f591475 (MD5) Previous issue date: 2012-11-10 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The Jatropha curcas L. is a vegetable species that supplies great amount of oil, but due to its toxicity cannot be used to feed human beings. It is a promising alternative for Biodiesel production. This Thesis had the purpose of perform analytic, thermal and energy studies for the oil extracted from oleaginous species Jatropha curcas L., cultivated in the State of Amazonas. The study was also done for byproducts such as fruit peels, seed peels and the cake originated by biofuel productive chain. To reach the proposed objective, the experimental activities were started with the sampling of the whole fruits in a plantation located in Itacoatiara city-Amazonas. Six independent samplings were done in different months and all the samples were submitted to physical characterization to evaluate size and weight for all parts of the fruit. The process to obtain the oil was done by two methods: mechanical extraction and chemical extraction (Soxhlet system). The chemical extraction was performed for all available samples and the best efficiency was the 50.21%, although all the extractions have presented good results (43-48%). The mechanical process was just performed for the 2010 crop presenting a satisfactory efficiency (33.14%). Then, the oil extracted by the two processes was characterized by several physical-chemical parameters. The oxidative stability by Rancimat was measured for the oils and the result was around 12 hours, this value is considered satisfactory when compared with other species. The fatty acid profile was analyzed by gas chromatography, which indicated the presence of higher concentrations of oleic and linoleic acids. The palmitic, stearic, arachidic and palmitoleic acids were also detected, however in smaller concentrations. The evaluation for thermal and energy potential was done for the oil and byproducts using TG/DTA, immediate analysis and superior heat power techniques. The results of thermal analysis for the oils obtained by chemical and mechanical extraction indicated thermal stability temperature about 180 and 217°C, respectively. Energy evaluation for byproducts was done by immediate analysis and high values for volatile materials were found (65-78%). These values characterize a fuel that can be easy and quickly burned during the combustion process. The results of PCS for the obtained oils presented high values (34-39 MJ/kg), which are close to the ones measured for diesel. For the byproducts, the results were between 17 and 21 MJ/kg, close and even superiors to the literature values for other agricultural residues showing, therefore, great applicability for use in energy generation processes. Finally, reactions with the Jatropha curcas L. oil were made to obtain biofuels through the methylic and ethylic transesterification and thermal cracking. The results for transesterification process were excellent, with efficiency above 90%, however, the physical-chemical evaluation showed that the methylic Biodiesel was the only one in conformity with the Resolution 14/2011 from ANP. A satisfactory efficiency of 75% was obtained for bio-oil. / O pinhão manso é uma espécie vegetal que fornece grande quantidade de óleo e por sua toxidade não pode ser usado na alimentação humana, podendo se transformar em uma alternativa promissora na produção de Biodiesel. Esta Tese teve a finalidade de realizar um estudo analítico, térmico e energético do óleo extraído da espécie oleaginosa pinhão manso (Jatropha curcas L.), cultivada no Estado do Amazonas, assim como dos co-produtos, tais como, cascas do fruto, cascas da semente e torta, presentes na cadeia produtiva de biocombustíveis. Para atingir o objetivo proposto, as atividades experimentais foram iniciadas com a coleta dos frutos na plantação localizada em Itacoatiara-AM. Foram feitas seis coletas em diferentes meses e todas as amostras foram submetidas à caracterização física avaliando o tamanho e a massa para todas as partes do fruto. Em seguida realizou-se o processo de obtenção do óleo, utilizando dois métodos, a extração mecânica e a extração com solvente (Método Soxhlet). A extração com solvente foi realizada para todas as amostras coletadas e o melhor rendimento obtido foi de 50,21%, apesar de ter obtido bons resultados em todas as extrações (43-48%). O processo mecânico foi realizado apenas com o lote da safra de 2010 apresentando um rendimento satisfatório (33,14%). Posteriormente, o óleo extraído foi caracterizado por diversos parâmetros físico-químicos. A estabilidade oxidativa por Rancimat foi realizada para o óleo do pinhão manso ficando em torno de 12 horas, um valor considerado satisfatório quando comparado com outras espécies. O perfil de ácidos graxos foi analisado por cromatografia gasosa, o qual indicou a presença de altas concentrações dos ácidos oléico e linoléico. Os ácidos palmítico, esteárico, araquídico e palmitoléico também foram detectados, porém em concentrações menores. A avaliação do potencial térmico e energético foi realizada para o óleo e os co-produtos utilizando as técnicas de TG/DTA, análise imediata e PCS. Os resultados da análise térmica dos óleos, obtidos via extração química e mecânica, indicaram uma temperatura de estabilidade térmica em torno de 180C e 217C, respectivamente. Na avaliação energética dos co-produtos realizada pela análise imediata houve destaque para o teor de materiais voláteis, que apresentou valores elevados (65-78%), o que caracteriza um combustível mais fácil e rapidamente queimado durante o processo de combustão. Os resultados do PCS para os óleos obtidos apresentaram valores elevados (34-39 MJ/kg) e próximos ao diesel. Para os co-produtos, os resultados ficaram entre 17 e 21 MJ/kg, próximos e até superiores aos valores reportados na literatura para outros resíduos agrícolas mostrando, portanto grande aplicabilidade para utilização em processos de geração de energia. Por fim foram realizadas reações com o óleo de pinhão manso para obter biocombustíveis através da transesterificação metílica e etílica e do craqueamento térmico. Os resultados da transesterificação mostraram-se excelentes, com rendimentos acima de 90%, entretanto a avaliação físico-química mostrou que apenas o Biodiesel metílico ficou em conformidade com a Resolução 14/2011 da ANP. O Bio-óleo obteve um rendimento satisfatório (75%).
9

Analýza vnitřního klimatu lázeňského komplexu / Analysis of indoor climate of spa resort

Chadima, Tomáš January 2019 (has links)
The thesis deals with the environmental assessment of buildings, concrete objects Letní lázně at Karlova Studánka. The first part describes the issue and legislation. There is also described a method of experimental measurement and methods of moisture measurement. The second part deals with the analysis of the specified object, description of selected renewable sources and description of possible modifications of the object. The third part is devoted to modeling and simulation of the specified object in DesignBuilder. Using the model were created various simulations with various modifications in order to reduce energy intensity of the object. Results were then evaluated and compared.
10

Energetické hodnocení budov / Energy Auditing of Building

Sýkorová, Iva January 2012 (has links)
Master´s thesis solves problematic of energy evaluation of residential building in Kyjov. The theoretical part analyzes the legislative requirements, the practical part includes energy audit of brick residential building with 9 apartments for 18 inhabitants.

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