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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.
21

Performance and power modeling of GPU systems with dynamic voltage and frequency scaling

Wang, Qiang 13 August 2020 (has links)
To address the ever-increasing demand for computing capacities, more and more heterogeneous systems have been designed to use both general-purpose and special-purpose processors. The huge energy consumption of them raises new environmental concerns and challenges. Besides performance, energy efficiency is another key factor to be considered by system designers and consumers. In particular, contemporary graphics processing units (GPUs) support dynamic voltage and frequency scaling (DVFS) to balance computational performance and energy consumption. However, accurate and straightforward performance and power estimation for a given GPU kernel under different frequency settings is still lacking for real hardware, which is essential to determine the best frequency configuration for energy saving. In this thesis, we investigate how to improve the energy efficiency of GPU systems by accurately modeling the effects of GPU DVFS on the target GPU kernel. We also propose efficient algorithms to solve the communication contention problem in scheduling multiple distributed deep learning (DDL) jobs on GPU clusters. We introduce our studies as follows. First, we present a benchmark suite EPPMiner for evaluating the performance, power, and energy of different heterogeneous systems. EPPMiner consists of 16 benchmark programs that cover a broad range of application domains, and it shows a great variety in the intensity of utilizing the processors. We have implemented a prototype of EPPMiner that supports OpenMP, CUDA, and OpenCL, and demonstrated its usage by three showcases. The showcases justify that GPUs provide much better energy efficiency than other types of computing systems, and especially illustrate the effectiveness of GPU Dynamic Voltage and Frequency Scaling (DVFS) on the energy efficiency of GPU applications. Second, we reveal a fine-grained analytical model to estimate the execution time of GPU kernels with both core and memory frequency scaling. Compared to the cycle-level simulators, which are too slow to apply on real hardware, our model only needs one-off micro-benchmarks to extract a set of hardware parameters and kernel performance counters without any source code analysis. Our experimental results show that the proposed performance model can capture the kernel performance scaling behaviors under different frequency settings and achieve decent accuracy. Third, we design a cross-benchmarking suite, which simulates kernels with a wide range of instruction distributions. The synthetic kernels generated by this suite can be used for model pre- training or as supplementary training samples. We then build machine learning models to predict the execution time and runtime power of a GPU kernel under different voltage and frequency settings. Validated on three modern GPUs with a wide frequency scaling range, by using a collection of 24 real application kernels, the model trained only with our cross-benchmarking suite is able to achieve considerably accurate results. At last, we establish a new DDL job scheduling framework which organizes DDL jobs as Directed Acyclic Graphs (DAGs) and considers communication contention between nodes. We then propose an efficient job placement algorithm, Least-Workload-First- (LWF-), to balance the GPU utilization and consolidate the allocated GPUs for each job. When scheduling the communication tasks, we propose Ada-SRSF for the DDL job scheduling problem to address the communication contention issue. Our simulation results show that LWF- achieves up to 1.59x improvement over the classical first-fit algorithms. More importantly, Ada-SRSF reduces the average job completion time by up to 36.7%, as compared to the solutions of either avoiding all the communication contention or accepting all of it
22

Improving Power Grid Economy Using Windpower Generation

Packiriswamy, Premkumar 09 August 2011 (has links)
No description available.
23

Examining The Role Of Intra-Household Bargaining In The Adoption Of Green Technology

Anand, Antara 01 January 2019 (has links)
This paper investigates factors that affect gender-based differences in intra-household bargaining power that are reflected in consumption decisions regarding the adoption of green technology. Using data from the Indian Human Development Survey-II and a probit regression analysis, I find that increasing the level of a woman’s education (a proxy for increasing bargaining power) increases the likelihood of her household adopting LPG, the cleanest fuel option available. I also create an experimental design to serve as a next step for future research and target data collection on individual-level factors and environmental outcomes. The setup is for a potential intervention that assesses whether there are gender-based differences in the propensity for men and women to purchase improved cookstoves, given increased access to credit as a means to increase bargaining power in the household.
24

Co-evolution toward sustainable development : neither smart technologies nor heroic choices

Brand, Ralf Gregor, 1970- 23 June 2011 (has links)
Not available / text
25

Attitudes towards new green technologies : a study of households using solar water heaters in low income RDP houses in Kwandengezi Coffee Farm, eThekwini Municipality.

Nxumalo, Omega Sibusiso. 29 October 2014 (has links)
Within the international context, energy has become a central factor in our everyday ways of life. There is increasing dependence on energy resources such as electricity to improve people quality of life. In developing countries, many people still do not have access to energy due to several challenges that have hindered infrastructural development and economic growth. At the same time, there is a growing interest in the protection of the environment and addressing issues of climate change. Green technologies such as solar water heaters are identified as technologies that meet the need of both its end-users and the environment through the provision of hot water. Access to 'hot water' is seen to be an important element resulting in an improved quality of life. In addition, several methods of heating water are explored to assess the attitudes and perceptions that people have towards solar water heaters. The dissertation involved in-depth interviews with residents from low income RDP houses in Kwandengezi Coffee Farm and government officials from eThekwini Municipality involved in the solar water heater programme for low income communities. The interviews revealed that renewable energy interventions such as the solar heater programme for low income communities contribute significantly to an improvement in people‘s quality of life. The availability of solar heaters allows people to enjoy hot water at a free cost, hence an improvement in the quality of life. The research further revealed that such renewable energy interventions can contribute to a reduction in negative environmental impacts, hence facilitating the acquisition of hot water with less dependence on electricity resources. / M.Dev.Studies University of KwaZulu-Natal, Durban 2013.
26

Environmental technology transfer : a case study of Quebec environmental firms in China

Gervais, Paul, 1974- January 1999 (has links)
As developing countries have grown aware of the effects of pollution and resource depletion, industrialized countries that produce environmental goods and services have secured new markets where to export them. In this manner, increased concerns over environmental degradation have led to the growth of the green technology sector which is currently in full expansion. The purpose of the thesis is, therefore, to uncover the dynamics of such exchanges by exploring the interactions of Quebec environmental firms in the People's Republic of China (PRC). / Results indicate that the PRC presents accommodative structures that are compatible with those found in Quebec, but an inappropriate level of protection of intellectual property rights (IPRs). This scenario gives the PRC a certain advantage since most local firms are able to reproduce foreign technologies without being constrained by issues of intellectual property. Combining theoretical and practical approaches, the thesis uncovers that accommodative conditions do not supersede the question of IPRs when attempting to ensure transfers. Even though the current state of these factors affects the nature of the agreements, the environmental aspect of these technologies seems to facilitate the transactions.
27

An empirical assessment of entry into the green power market /

Mester, Gretchen S., January 2004 (has links)
Thesis (Ph. D.)--University of Oregon, 2004. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 93-96). Also available for download via the World Wide Web; free to University of Oregon users.
28

Modeling and analysis of the biorefinery integrated with the agricultural landscape

Sendich, Elizabeth Diane. January 2008 (has links)
Thesis (PH.D.)--Michigan State University. Chemical Engineering, 2008. / Title from PDF t.p. (viewed on Aug. 11, 2009) Includes bibliographical references (p. 179-189). Also issued in print.
29

A educação ambiental como ferramenta para minimização e valorização de resíduos sólidos urbanos em um colégio de Mandirituba/PR

Oliveira, Everton Mario de 31 July 2014 (has links)
A geração de resíduos sólidos urbanos vem aumentando muito nas últimas décadas. Isto, aliado à gestão inadequada desses resíduos, tem contribuído para o agravamento de problemas ambientais. Porém, nos últimos anos muitos países começaram a melhorar seus sistemas de gestão de resíduos sólidos. Uma das técnicas que os órgãos públicos estão utilizando para reduzir a totalidade dos resíduos sólidos que são geridos por eles, é o desenvolvimento e aplicação de projetos de educação ambiental na comunidade, incentivando práticas ambientalmente corretas de gestão de resíduos. Assim, esta pesquisa teve como objetivo aplicar ações educativas voltadas à educação ambiental em um colégio público do município de Mandirituba/PR, como método para minimização e valorização de resíduos sólidos urbanos. Para isto, primeiro foi realizado um diagnóstico da percepção ambiental dos alunos que estudam no colégio em relação aos resíduos sólidos; e na sequência foram desenvolvidas as seguintes atividades: uma palestra interativa, uma gincana, uma competição de coleta de resíduos recicláveis, a construção e instalação de coletores coloridos, e a exposição de painéis, todas essas atividades visando à sensibilização ambiental quanto à minimização de resíduos sólidos. No diagnóstico da percepção ambiental dos alunos, notou-se que, de forma geral, os estudantes apresentaram uma percepção ambiental incipiente, pois não souberam responder a algumas questões; e, não foi percebida uma conscientização em todos os indivíduos da comunidade, sendo que muitos não realizam a separação e a destinação adequada dos resíduos sólidos; também percebeu-se a importância da escola como veículo de formação de conhecimento, sendo considerada o ambiente mais propício ao desenvolvimento de estratégias de educação ambiental. Durante a realização das palestras, percebeu-se que os alunos demonstraram interesse pelo tema, interagindo com o palestrante; após a palestra e a gincana, percebeu-se uma melhora na percepção dos discentes referente a resíduos sólidos tais como: reforçaram conhecimentos referentes à coleta seletiva e técnicas de redução de resíduos sólidos; foram expostas opiniões sobre a importância da separação dos resíduos; e, foram apresentadas ideias para promover a minimização da geração dos resíduos sólidos. A competição de coleta de resíduos recicláveis promoveu a interação do aluno com o meio no qual transcorre o seu dia-a-dia, o que pode levá-lo a valorizar esse espaço. A construção e instalação dos coletores coloridos despertou o interesse dos alunos para a separação e reciclagem dos resíduos. Os painéis expostos divulgam a informação e contribuem para o processo de sensibilização dos indivíduos. Assim, as atividades desenvolvidas proporcionaram a sensibilidade e a consciência dos alunos quanto às práticas mais sustentáveis de geração de resíduos sólidos. O caráter lúdico incorporado nessas atividades proporcionou uma sensibilização mais apropriada, pois permitiu o desenvolvimento do conhecimento de maneira prazerosa. / The generation of municipal solid waste has been increasing in recent decades. This, coupled with inadequate management of these wastes has contributed to the worsening of environmental problems. However, in recent years many countries have begun to improve their systems for solid waste management. One of the techniques that public bodies are using to reduce the total solid waste that are managed by them, is the development and application of environmental education projects in the community, encouraging environmentally sound waste management practices. Thus, this study aimed to apply educational activities aimed at environmental education in a public school in the municipality of Mandirituba / PR as a method for minimization and recycling of municipal solid waste. For this, first a diagnosis of environmental perception of students studying at the college in relation to solid waste was conducted; and following the following activities were developed: an interactive lecture, a scavenger hunt, a competition of collecting recyclable waste, construction and installation of colored collectors, and the exposure of panels, all these activities aimed at environmental awareness regarding waste minimization solids. Diagnosis of environmental perception of students, it was noted that, in general, students showed an incipient environmental perception, because no answer to some questions; and was not perceived an awareness in all individuals of the community, and many do not realize the separation and proper disposal of solid waste; also realized the importance of the school as a vehicle for knowledge building and is considered the most suitable for the development of strategies for environmental education environment. During the campain, it was noticed that the students showed interest in the subject, interacting with the speaker; after the lecture and the gymkhana, felt an improvement in the perception of students regarding solid waste such as reinforced knowledge and techniques related to selective collection of solid waste reduction; opinions on the importance of waste separation were exposed; and ideas to promote minimizing the generation of solid waste were presented. The competition for collecting recyclable waste promoted student interaction with the environment in which passes your day-to-day, which can lead you to treasure this space. The construction and installation of the colored collectors sparked the interest of the students for the separation and recycling of waste. The panels exposed disclose the information and contribute to the process of sensitization of individuals. Thus, the activities provided the sensitivity and awareness of the students as the most sustainable practices in solid waste generation. The playful character embedded in these activities provided a more appropriate sensitization, as it allowed the development of knowledge in an enjoyable way.
30

Avaliação de sistemas de telhados verdes : análise térmica e hídrica nos diferentes sistemas cultivados com Callisia repens /

Carvalho, Gustavo de Castro. January 2018 (has links)
Orientador: Paulo Sergio Tonello / Coorientador: Jarbas Honorio de Miranda / Banca: Antonio Cesar Germano Martins / Banca: Késia Oliveira da Silva Miranda / Resumo: A crescente urbanização, faz com que problemas ambientais tornem-se cada vez mais frequentes e, dessa forma, alternativas como o uso de coberturas vegetais mostram-se como importantes ferramentas para a melhoria ambiental nos centros urbanos. Telhados verdes são sistemas construtivos que quando utilizados, trazem inúmeros benefícios à população, dentre os quais se destacam: melhoria no conforto térmico em edificações, diminuição da poluição atmosférica, acústica e visual, além de menor escoamento superficial, reduzindo enchentes. Diante disso, a presente pesquisa buscou avaliar a temperatura em protótipos com diferentes sistemas de telhados verdes comerciais (Sistema FLAT, Sistema Modular e Sistema MacDrain) cultivados com Callisia repens, para quantificar a melhoria no que diz respeito ao conforto térmico que esses sistemas proporcionam, comparando-os entre si e com um sistema testemunha, totalizando 4 protótipos. A coleta dos dados ocorreu no período de 09/08/2017 à 22/11/2017 através de sensores de temperatura automatizados, em três diferentes horários: 08:00, 13:00 e às 22:00 horas. Adotouse o delineamento experimental de blocos ao acaso, e foram realizadas análises estatísticas para a comparação dos resultados, através do Teste de Tukey a 5% de significância. Os resultados mostraram que em horários com valores maiores de temperatura, os sistemas conseguem atenuar a radiação solar, diminuindo a transferência de calor do meio externo para o compartimento instalado logo aba... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The crescent urbanization makes that environmental problems become more frequent and, therefore, alternatives as the use of plant cover are important for the environmental improvement. The green roofs are constructive systems that when used bring countless benefits to the population, to name but a few, thermal comfort improvement in buildings, decrease of the atmosphere pollution, acoustic and visual, besides a larger surface flow reducing floods. Therefore, the present dissertation has evaluated the temperature in different green roof systems prototypes cultivated with Callisia repens, to quantify the improvement related to the thermal comfort that these systems provide, comparing them with each other and with a control system, totaling 4 prototypes. Data were collected from 09/08/2017 to 11/22/2017 by automated alerts, at three different times: 08:00am, 01:00pm and 10:00pm. To compare statistically the results, critical analyses were carried out using the Tukey test at 5% significance level. The results have showed that with higher temperatures, the systems are able to weaken the solar radiation, reducing the heat transfer from the external environment to the compartment just below the prototypes. On the other hand, at night, normally with mild temperatures, the system works by keeping the heat absorbed during the day in the compartment below, isolating the loss of heat. Although most of the internal temperature levels are not within the limits of thermal comfort zone, the ... (Complete abstract click electronic access below) / Mestre

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