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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

Firm Behavior, Environmental Externalities and Public Policy

Curtis, Earnest 01 August 2014 (has links)
This dissertation consists of three essays which examine environmental policy, employer mandates and energy consumption. The essays explore how firms respond to government policies such as environmental regulation and employer mandates. Understanding how firms adjust to government policies is crucial to law makers attempting to design optimal policies that maximize net benefits to society. The first essay, titled Who Loses under Power Plant Cap-and-Trade Programs tests how a major cap-and-trade program, known as the NOx Budget Trading Program (NBP), affected labor markets in the region where it was implemented. The cap-and-trade program dramatically decreased levels of NOx emissions and added substantial costs to energy producers. Using a triple-differences approach that takes advantage of the geographic and time variation of the program as well as variation in industry energy-intensity levels, I examine how employment dynamics changed in manufacturing industries whose production process requires high levels of energy. After accounting for a variety of flexible state, county and industry trends, I find that employment in the manufacturing sector dropped by 1.7% as a result of the NBP. Young workers experienced the largest employment declines and earnings of newly hired workers fell after the regulation began. Employment declines are shown to have occurred primarily through decreased hiring rates rather than increased separation rates, thus mitigating the impact on incumbent workers. The second essay, titled Evaluating Workplace Mandates with Flows versus Stocks: An Application to California Paid Family Leave uses an underexploited data set to examine the impact of the California Paid Family Leave program on employment outcomes for young women. Most papers on mandated benefits examine labor outcomes by looking at earnings and employment levels of all workers. Examining these levels will be imprecise if the impacts of the program develop over time and firms are wary to immediately adjust employment and wages for existing workers. Using Quarterly Workforce Indicator data, we are able to measure the impact on hires, new hire earnings, separations and extended leaves among young women. Earnings for young female new hires fell in California relative to other workers, but changed little relative to country-wide comparison groups. We find strong evidence that separations (of at least three months) among young women and the number and shares of young female new hires increased. Many young women that separate (leave the payroll) eventually return to the same firm. Increased separation and hiring rates among young women in the labor market (“churning”) may reflect both increased time spent with children and greater job mobility (i.e., reduced job lock) as the result of mandated paid family leave across the labor market. The third essay, Evidence of an Energy Management Gap in U.S. Manufacturing: Spillovers from Firm Management Practices to Energy Efficiency, merge a well-cited survey of firm management practices into confidential plant level U.S. Census manufacturing data to examine whether generic, i.e. non-energy specific, firm management practices, ”spillover” to enhance energy efficiency in the United States. For U.S. manufacturing plants we find this relationship to be more nuanced than prior research on UK plants. Most management techniques are shown to have beneficial spillovers to energy efficiency, but an emphasis on generic targets, conditional on other management practices, results in spillovers that increase energy intensity. Our specification controls for industry specific effects at a detailed 6-digit NAICS level and finds the relationship between management and energy use to be strongest for firms in energy intensive industries. We interpret the empirical result that generic management practices do not necessarily spillover to improved energy performance as evidence of an “energy management gap.”
42

Energy Efficient RPL Routing Protocol in Smart Buildings

Rezaei, Elnaz January 2014 (has links)
Energy is an important factor that must be considered by multi-hop wireless mesh routing protocols because most sensors are powered by batteries with a limited capacity. We focus on the industry-standard RPL (Routing Protocol over Low-power and lossy networks) routing protocol that must find energy-efficient paths in low-power and lossy networks. However, the existing RPL objective functions route based on hop-count and ETX (expected transmission count) metrics alone, ignoring the energy cost of data transmission and reception. We address this issue in two ways. First, we design an objective function for RPL that finds paths that require, in expectation, the minimum amount of energy. Second, we design a probing mechanism which configures the transmission power of sensors to minimize energy consumption. The proposed approach is implemented and evaluated using simulations as well as on a small testbed with two Zolertial Z1 motes.
43

Analyzing sustainable energy opportunities for a small scale off-grid facility: a case study at Experimental Lakes Area (ELA), Ontario

Duggirala, Bhanu 27 July 2010 (has links)
This thesis explored the opportunities to reduce energy demand and renewable energy feasibility at an off-grid science “community” called the Experimental Lakes Area (ELA) in Ontario. Being off-grid, ELA is completely dependent on diesel and propane fuel supply for all its electrical and heating needs, which makes ELA vulnerable to fluctuating fuel prices. As a result ELA emits a large amount of greenhouse gases (GHG) for its size. Energy efficiency and renewable energy technologies can reduce energy consumption and consequently energy cost, as well as GHG. Energy efficiency was very important to ELA due to the elevated fuel costs at this remote location. Minor upgrades to lighting, equipment and building envelope were able to reduce energy costs and reduce load. Efficient energy saving measures were recommended that save on operating and maintenance costs, namely, changing to LED lights, replacing old equipment like refrigerators and downsizing of ice makers. This resulted in a 4.8% load reduction and subsequently reduced the initial capital cost for biomass by $27,000, by $49,500 for wind power and by $136,500 for solar power. Many alternative energies show promise as potential energy sources to reduce the diesel and propane consumption at ELA including wind energy, solar heating and bio-mass. A biomass based CHP system using the existing diesel generators as back-up has the shortest pay back period of the technologies modeled. The biomass based CHP system has a pay back period of 4.1 years at $0.80 per liter of diesel, as diesel price approaches $ 2.00 per liter the pay back period reduces to 0.9 years, 50% the generation cost compared to present generation costs. Biomass has been successfully tried and tested in many off-grid communities particularly in a small-scale off-grid setting in North America and internationally. Also, the site specific solar and wind data show that ELA has potential to harvest renewable resources and produce heat and power at competitive rates compared to diesel and propane.
44

Maximizing energy savings reliability in BC Hydro industrial Demand-Side Management programs: an assessment of performance incentive models.

Gosman, Nathaniel 29 August 2012 (has links)
For energy utilities faced with expanded jurisdictional energy efficiency requirements and pursuing demand-side management (DSM) incentive programs in the large industrial sector, performance incentive programs can be an effective means to maximize the reliability of planned energy savings. Performance incentive programs balance the objectives of high participation rates with persistent energy savings by: (1) providing financial incentives and resources to minimize constraints to investment in energy efficiency, and (2) requiring that incentive payments be dependent on measured energy savings over time. As BC Hydro increases its DSM initiatives to meet the Clean Energy Act objective to reduce at least 66 per cent of new electricity demand with DSM by 2020, the utility is faced with a higher level of DSM risk, or uncertainties that impact the cost-effective acquisition of planned energy savings. For industrial DSM incentive programs, DSM risk can be broken down into project development and project performance risks. Development risk represents the project ramp-up phase and is the risk that planned energy savings do not materialize due to low customer response to program incentives. Performance risk represents the operational phase and is the risk that planned energy savings do not persist over the effective measure life. DSM project development and performance risks are, in turn, a result of industrial economic, technological and organizational conditions, or DSM risk factors. In the BC large industrial sector, and characteristic of large industrial sectors in general, these DSM risk factors include: (1) capital constraints to investment in energy efficiency, (2) commodity price volatility, (3) limited internal staffing resources to deploy towards energy efficiency, (4) variable load, process-based energy saving potential, and (5) a lack of organizational awareness of an operation’s energy efficiency over time (energy performance). This research assessed the capacity of alternative performance incentive program models to manage DSM risk in BC. Three performance incentive program models were assessed and compared to BC Hydro’s current large industrial DSM incentive program, Power Smart Partners – Transmission Project Incentives, itself a performance incentive-based program. Together, the selected program models represent a continuum of program design and implementation in terms of the schedule and level of incentives provided, the duration and rigour of measurement and verification (M&V), energy efficiency measures targeted and involvement of the private sector. A multi criteria assessment framework was developed to rank the capacity of each program model to manage BC large industrial DSM risk factors. DSM risk management rankings were then compared to program cost-effectiveness, targeted energy savings potential in BC and survey results from BC industrial firms on the program models. The findings indicate that the reliability of DSM energy savings in the BC large industrial sector can be maximized through performance incentive program models that: (1) offer incentives jointly for capital and low-cost operations and maintenance (O&M) measures, (2) allow flexible lead times for project development, (3) utilize rigorous M&V methods capable of measuring variable load, process-based energy savings, (4) use moderate contract lengths that align with effective measure life, and (5) integrate energy management software tools capable of providing energy performance feedback to customers to maximize the persistence of energy savings. While this study focuses exclusively on the BC large industrial sector, the findings of this research have applicability to all energy utilities serving large, energy intensive industrial sectors. / Graduate
45

Sistemas de controle solar e ações de retrofitting

Nuss, Claudio Andre January 2018 (has links)
Os sistemas de controle solar auxiliam no controle da radiação solar incidente no envoltório, e, de acordo com a NBR 15220-3, é recomendável seu uso para a zona bioclimática 3, na cidade de Porto Alegre. Assim, com a ação de retrofitting, é possível utilizar os sistemas de controle solar como modo de adaptar o envoltório das edificações ao clima local e aos padrões de consumo atuais. Dessa forma, o retrofitting do envoltório pode contribuir com a redução do consumo energético e a dependência de sistemas de refrigeração e aquecimento mecânico. Logo, o objetivo da dissertação é qualificar e quantificar energeticamente os sistemas de controle solar com vistas à redução do consumo energético nos ambientes construídos. Um estudo de caso foi realizado na cidade de Porto Alegre, onde um edifício foi selecionado perante um conjunto de edificações existentes. Com o auxílio de um método expedito de cálculo energético, foi realizada a avaliação energética do envoltório da edificação atual e do seu retrofitting proposto. A edificação passou de nível energético E para nível A, comprovando o êxito do estudo de retrofitting aplicado. A pesquisa concluiu que, alinhado com o encontrado na revisão da literatura, as edificações com grandes aberturas orientadas para oeste são um equívoco de projeto no clima de Porto Alegre e que as ações de retrofitting são uma alternativa de adaptação ao clima local, tornando os edifícios eficientes energeticamente. / Shading systems help to control the incident solar radiation on the envelope, and, according to NBR 15220-3, its use is recommended for the bioclimatic zone 3, in the city of Porto Alegre. Hence, with retrofitting, it is possible to use shading systems as a way of adapting the building envelope to the local climate and current consumption patterns. Thus, the retrofitting of the envelope can contribute to the reduction of the energy consumption and of the dependence on systems of refrigeration and mechanical heating. Therefore, the objective of this dissertation is to qualify and quantify the energy of shading systems in order to reduce energy consumption in built environments. Thus, a case study was conducted in the city of Porto Alegre, where a building was selected from a set of existing buildings. We performed an energetic evaluation of current envelope of buildings and its proposed retrofitting by using a facilitated method for energy calculation. The buildings moved from energy level E to level A, proving the success of the study on the applied retrofitting. We conclude that, as also shown in literature review; buildings with large openings oriented to the west in Porto Alegre are a design misconception due to the city’s climate. Thus, retrofitting actions are alternative ways to adapt to the local climate so that buildings are energy efficient.
46

REDESIGN OF HVAC SYSTEM TO IMPROVE ENERGY EFFICIENCY OF EDUCATIONAL BUILDING

Hagene, Brian Matthew 01 May 2012 (has links)
An energy modeling software was used to analyze the current building configuration and simulations were performed in an attempt to redesign the current HVAC system of an educational building to improve the energy efficiency of the building, exceed current building code requirements, and meet the building's cooling and heating load. The different HVAC systems simulated were: Dual Air Duct, Variable-Air Volume (VAV), and Dedicated Outdoor Air Systems (DOAS). Each system was modeled in four operation schedules including: current system operation, fan control, lighting control, and lighting and fan control. These operation schedules are to represent how efficient the building would be in different controlled settings. Results were obtained regarding the energy requirements of the different HVAC systems. For the educational building both VAV and DOAS systems offer 48.8% and 57.9%, respectively, in annual savings in energy use, achieved by adding controls to the lights and fans of both systems reducing energy consumed by ventilation fans. The time of a simple payback period for a new VAV and DOAS system is 10.2 and 9.35 years, respectively, and may remove any considerations to implement a new HVAC system. Based on these findings, educational buildings using Dual Duct should consider using DOAS systems.
47

Sistemas de controle solar e ações de retrofitting

Nuss, Claudio Andre January 2018 (has links)
Os sistemas de controle solar auxiliam no controle da radiação solar incidente no envoltório, e, de acordo com a NBR 15220-3, é recomendável seu uso para a zona bioclimática 3, na cidade de Porto Alegre. Assim, com a ação de retrofitting, é possível utilizar os sistemas de controle solar como modo de adaptar o envoltório das edificações ao clima local e aos padrões de consumo atuais. Dessa forma, o retrofitting do envoltório pode contribuir com a redução do consumo energético e a dependência de sistemas de refrigeração e aquecimento mecânico. Logo, o objetivo da dissertação é qualificar e quantificar energeticamente os sistemas de controle solar com vistas à redução do consumo energético nos ambientes construídos. Um estudo de caso foi realizado na cidade de Porto Alegre, onde um edifício foi selecionado perante um conjunto de edificações existentes. Com o auxílio de um método expedito de cálculo energético, foi realizada a avaliação energética do envoltório da edificação atual e do seu retrofitting proposto. A edificação passou de nível energético E para nível A, comprovando o êxito do estudo de retrofitting aplicado. A pesquisa concluiu que, alinhado com o encontrado na revisão da literatura, as edificações com grandes aberturas orientadas para oeste são um equívoco de projeto no clima de Porto Alegre e que as ações de retrofitting são uma alternativa de adaptação ao clima local, tornando os edifícios eficientes energeticamente. / Shading systems help to control the incident solar radiation on the envelope, and, according to NBR 15220-3, its use is recommended for the bioclimatic zone 3, in the city of Porto Alegre. Hence, with retrofitting, it is possible to use shading systems as a way of adapting the building envelope to the local climate and current consumption patterns. Thus, the retrofitting of the envelope can contribute to the reduction of the energy consumption and of the dependence on systems of refrigeration and mechanical heating. Therefore, the objective of this dissertation is to qualify and quantify the energy of shading systems in order to reduce energy consumption in built environments. Thus, a case study was conducted in the city of Porto Alegre, where a building was selected from a set of existing buildings. We performed an energetic evaluation of current envelope of buildings and its proposed retrofitting by using a facilitated method for energy calculation. The buildings moved from energy level E to level A, proving the success of the study on the applied retrofitting. We conclude that, as also shown in literature review; buildings with large openings oriented to the west in Porto Alegre are a design misconception due to the city’s climate. Thus, retrofitting actions are alternative ways to adapt to the local climate so that buildings are energy efficient.
48

Gestão energética e ambiental de edificações: avaliação de metodologias para certificação

Ruzene, Juliana Santos [UNESP] 02 September 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-09-02Bitstream added on 2014-06-13T19:16:37Z : No. of bitstreams: 1 ruzene_js_me_guara.pdf: 944530 bytes, checksum: 8ee6e0a711627cfaf412e1c2b8e93560 (MD5) / O sistema LEED (Leadership in Energy and Environmental Design) consiste numa metodologia para avaliar o desempenho energético e ambiental de edificações ao longo de seu ciclo de vida, tendo como objetivo direcionar ações para o conceito de edificações sustentáveis (green buildings) e fornecer uma padronização para medir a dimensão ambiental relativa dos projetos. No Brasil, a Eletrobrás, através do Programa Nacional de Conservação de Energia Elétrica (Procel) e em parceria com o Instituto Nacional de Metrologia, Normalização e Qualidade Industrial (Inmetro), lançaram a Etiqueta Nacional de Eficiência Energética em Edificações (ENCE), para edifícios comerciais, de serviços e públicos, reconhecendo edificações que reduzam o consumo de energia elétrica e água. Neste trabalho foi realizado um estudo de certificação energética e ambiental de edificações, bem como a identificação de alternativas técnicas para o enquadramento em níveis mais adequados e correspondente estudo de viabilidade econômica. Como estudo de caso, o edifício da Fundação existente no Campus de Guaratinguetá da UNESP foi analisado de acordo com os preceitos da avaliação de desempenho de ambas as metodologias. Com base nos resultados obtidos, foram realizadas sugestões de tecnologias e modificações possíveis de serem implantadas / The LEED system (Leadership in Energy and Environmental Design) is a methodology for evaluating the energetic and environmental performance of buildings throughout their life cycle, aiming to guide actions for the concept of green building and provide a standard for measuring the size on environmental projects. In Brazil, Eletrobras, through the National Program for Energy Conservation (PROCEL) and in partnership with the National Institute of Metrology, Standardization and Industrial Quality (Inmetro), launched the Label National Energy Efficiency in Buildings (ENCE), for commercial buildings, and public service, recognizing buildings that reduce the consumption of electricity and water. In this research report it was presented an environmental and energetic certification of buildings study, as well as the analysis of technical solutions for the framework in more appropriate levels, and corresponding economic feasibility study. As a case study, the Foundation's existing building on the campus of UNESP at Guaratinguetá was analyzed in accordance with the principles of performance evaluation of both approaches. Based on these results, suggestions were made of possible technologies and changes being implemented
49

Ultra low power cooperative branch prediction

Bielby, Matthew Iain January 2015 (has links)
Branch Prediction is a key task in the operation of a high performance processor. An inaccurate branch predictor results in increased program run-time and a rise in energy consumption. The drive towards processors with limited die-space and tighter energy requirements will continue to intensify over the coming years, as will the shift towards increasingly multicore processors. Both trends make it increasingly important and increasingly difficult to find effective and efficient branch predictor designs. This thesis presents savings in energy and die-space through the use of more efficient cooperative branch predictors achieved through novel branch prediction designs. The first contribution is a new take on the problem of a hybrid dynamic-static branch predictor allocating branches to be predicted by one of its sub-predictors. A new bias parameter is introduced as a mechanism for trading off a small amount of performance for savings in die-space and energy. This is achieved by predicting more branches with the static predictor, ensuring that only the branches that will most benefit from the dynamic predictor’s resources are predicted dynamically. This reduces pressure on the dynamic predictor’s resources allowing for a smaller predictor to achieve very high accuracy. An improvement in run-time of 7-8% over the baseline BTFN predictor is observed at a cost of a branch predictor bits budget of much less than 1KB. Next, a novel approach to branch prediction for multicore data-parallel applications is presented. The Peloton branch prediction scheme uses a pack of cyclists as an illustration of how a group of processors running similar tasks can share branch predictions to improve accuracy and reduce runtime. The results show that sharing updates for conditional branches across the existing interconnect for I-cache and D-cache updates results in a reduction of mispredictions of up to 25% and a reduction in run-time of up to 6%. McPAT is used to present an energy model that suggests the savings are achieved at little to no increase in energy required. The technique is then extended to architectures where the size of the branch predictors may differ between cores. The results show that such heterogeneity can dramatically reduce the die-space required for an accurate branch predictor while having little impact on performance and up to 9% energy savings. The approach can be combined with the Peloton branch prediction scheme for reduction in branch mispredictions of up to 5%.
50

FULL-VIEW COVERAGE PROBLEMS IN CAMERA SENSOR NETWORKS

Li, Chaoyang 08 August 2017 (has links)
Camera Sensor Networks (CSNs) have emerged as an information-rich sensing modality with many potential applications and have received much research attention over the past few years. One of the major challenges in research for CSNs is that camera sensors are different from traditional scalar sensors, as different cameras from different positions can form distinct views of the object in question. As a result, simply combining the sensing range of the cameras across the field does not necessarily form an effective camera coverage, since the face image (or the targeted aspect) of the object may be missed. The angle between the object's facing direction and the camera's viewing direction is used to measure the quality of sensing in CSNs instead. This distinction makes the coverage verification and deployment methodology dedicated to conventional sensor networks unsuitable. A new coverage model called full-view coverage can precisely characterize the features of coverage in CSNs. An object is full-view covered if there is always a camera to cover it no matter which direction it faces and the camera's viewing direction is sufficiently close to the object's facing direction. In this dissertation, we consider three areas of research for CSNS: 1. an analytical theory for full-view coverage; 2. energy efficiency issues in full-view coverage CSNs; 3. Multi-dimension full-view coverage theory. For the first topic, we propose a novel analytical full-view coverage theory, where the set of full-view covered points is produced by numerical methodology. Based on this theory, we solve the following problems. First, we address the full-view coverage holes detection problem and provide the healing solutions. Second, we propose $k$-Full-View-Coverage algorithms in camera sensor networks. Finally, we address the camera sensor density minimization problem for triangular lattice based deployment in full-view covered camera sensor networks, where we argue that there is a flaw in the previous literature, and present our corresponding solution. For the second topic, we discuss lifetime and full-view coverage guarantees through distributed algorithms in camera sensor networks. Another energy issue we discuss is about object tracking problems in full-view coverage camera sensor networks. Next, the third topic addresses multi-dimension full-view coverage problem where we propose a novel 3D full-view coverage model, and we tackle the full-view coverage optimization problem in order to minimize the number of camera sensors and demonstrate a valid solution. This research is important due to the numerous applications for CSNs. Especially some deployment can be in remote locations, it is critical to efficiently obtain accurate meaningful data.

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