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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.
31

The rhythm of life is a powerful beat : demand response opportunities for time-shifting domestic electricity practices

Higginson, Sarah L. January 2014 (has links)
The 2008 Climate Change Act set legally-binding carbon reduction targets. Demand side management (DSM) includes energy use reduction and peak shaving and offers significant potential to reduce the amount of carbon used by the electricity grid. The demand side management (DSM) schemes that have tried to meet this challenge have been dominated by engineering-based approaches and so favour tools like automation (which aims to make shifting invisible) and pricing (which requires customer response) to shift demand. These approaches tend to focus on the tools for change and take little account of people and energy-use practices. This thesis argues that these approaches are limited and therefore unlikely to produce the level of response that will be needed in future. The thesis therefore investigates the potential for time-shifting domestic energy demand but takes a different angle by trying to understand how people use energy in their daily lives, whether this use can be shifted and some of the implications of shifting it. The centrepiece of the work is an empirical study of eleven households energy-use practices. The interdisciplinary methodology involved in-house observations, interviews, photographs, metered energy data and disruptive interventions. The data was collected in two phases. Initially, a twenty-four hour observation was carried out in each household to find out how energy was implicated in everyday practices. Next, a series of three challenges were carried out, aimed at assessing the implications of disrupting practices by time-shifting food preparation, laundry and work/ leisure. A practice theory approach is used to shift the focus of attention from appliances, tools for change, behaviour or even people, to practices. The central finding of this work is that practices were flexible. This finding is nuanced, in the light of the empirical research, by an extended discussion on the nature of practices; in particular, the relationship between practices and agency and the temporal-spatial locatedness of practices. The findings demonstrate that, in this study at least, expanding the range of demand response options was possible. The research suggests numerous possibilities for extending the potential of practices to shift in time and space, shift the energy used in practices or substitute practices for other non-energy-using practices, though there are no simple technological or behavioural fixes . More profoundly, however, the thesis concludes that infrastructures of provision , such as the electricity grid and the companies that run it, underpin and facilitate energy-use practices irrespective of the time of day and year. In this context technology-led demand response schemes may ultimately contribute to the problem they purport to solve. A more fundamental interrogation of demand and the infrastructures that serve it is therefore necessary and is almost entirely absent from the demand response debate.
32

Avaliação de critério pós-operatório de insuficiência hepática como fator prognóstico de mortalidade após hepatectomia: importância da alteração combinada do tempo de protrombina e da bilirrubina sérica / Evaluation of postoperative criteria of liver failure as a prognostic factor of mortality after hepatectomy: importance of the combined alteration of prothrombin time and serum bilirubin

Balzan, Silvio Márcio Pegoraro 27 September 2006 (has links)
INTRODUÇÃO. A definição de insuficiência hepática pós-operatória (IHP) não é ainda padronizada, dificultando a comparação de inovações em procedimentos hepáticos e tornando complexo o uso de possíveis intervenções terapêuticas pós- operatórias em um momento adequado. CASUÍSTICA E MÉTODOS. Entre 1998 e 2002, 775 resecções hepáticas eletivas, dos quais 531 (69%) por doenças malignas e 464 (60%) consistindo em hepatectomias maiores, foram incluídas de maneira prospectiva em um banco de dados. O parênquima hepático não-tumoral foi anormal em 330 pacientes (43%) incluindo esteatose em mais que 30% dos hepatócitos em 107 (14%), fibrose sem cirrose em 237 (43%) e cirrose em 94 (12%). Foi analisado o impacto sobre a mortalidade da ocorrência de tempo de protrombina (TP) menor que 50% e bilirrubina total sérica (BT) maior que 50 µmol/L (3 mg/dl) (critério 50-50) nos dias pós-operatórios (PO) 1, 3, 5 e 7. RESULTADOS. A cinética pós-operatória do TP e da BT foram diferentes. O menor nível de TP foi no primeiro dia pós-operatório (PO) e o pico de BT foi no terceiro dia PO. A tendência ao retorno para valores pré-operatórios destes dois fatores bioquímicos se firmou claramente no quinto DPO. A mortalidade operatória global foi de 3.4% (26 pacientes), incluindo 21 (81%) casos com parênquima não-tumoral anormal e 20 (77%) após uma hepatectomia maior. O índice de mortalidade foi maior em pacientes com TP < 50% ou BT > 50 µmol/L (3 mg/dl) no pós-operatório. A conjunção de TP < 50% e BT > 50 µmol/L (3 mg/dl) no quinto DPO foi potente fator preditivo de mortalide, a qual atingiu 59% quando esta associação ocorreu. CONCLUSÕES. A partir do quinto dia PO, a associação de TP > 50% e BT > 50 µml/L (3 mg/dl) (critério 50-50) foi preditor prático e acurado de índice de mortalidade após hepatectomia. Propõe-se assim este critério como definição de insuficiência hepática pós-operatória. / INTRODUCTION. Definition of postoperative liver failure (PLF) is not standardized, rendering complex the comparison of novelties in liver procedures and also the use of possible postoperative therapeutic interventions in due time. METHODS. Between 1998 and 2002, 775 elective liver resections, whence 531 (69%) were for malignancies and 464 (60%) for major resections, were included in a prospective database. The non- tumorous hepatic parenchima was abnormal in 330 patients (43%) including steatosis > 30% in 107 (14%), non-cirrhotic fibrosis in 237 (43%) and cirrhosis in 94 (12%). The clinical impact of Prothrombin Time (PT) < 50% and Serum Bilirubin (SB) > 50µmol/L (3 mg/dl) (50-50 criteria) on postoperative days (POD) 1, 3, 5 and 7 was analyzed. RESULTS. Kinetic of postoperative PT and SB were different. Lowest PT levels were on POD1 and the peak of SB was on POD 3. The tendency to return to preoperative values of these two biochemical factors was clearly affirmed on POD 5. Operative mortality was 3.4% (26 patients), including 21 (81%) cases with abnormal liver parenchyma and 20 (77%) following major hepatectomies. Mortality rate was increased in patients with PT < 50% or SB > 50µmol/L (3mg/dl). The conjunction of PT < 50% and SB > 50µmol/L (3 mg/dl) on POD 5 was a strong predictive factor of increased mortality, which reached 59%. CONCLUSIONS We found that after postoperative day 5, the association of PT > 50% and SB > 50µml/L (3 mg/dl) (50-50 criteria) was a simple and accurate predictor of mortality after hepatectomy. These results allow us to propose this criteria as a definition of postoperative liver failure.
33

Medidor de Energia para Avalia??o da Ades?o ? Tarifa Branca em Smart Grids / Energy Meter for Evaluation of Adoption of White Tariff in Smart Grids

Lemos, Ivan Pedrotti 08 February 2017 (has links)
Submitted by SBI Biblioteca Digital (sbi.bibliotecadigital@puc-campinas.edu.br) on 2017-03-23T13:48:47Z No. of bitstreams: 1 IVAN PEDROTTI LEMOS.pdf: 2401459 bytes, checksum: f02681540995cdcf4ae8524cff81fb9c (MD5) / Made available in DSpace on 2017-03-23T13:48:47Z (GMT). No. of bitstreams: 1 IVAN PEDROTTI LEMOS.pdf: 2401459 bytes, checksum: f02681540995cdcf4ae8524cff81fb9c (MD5) Previous issue date: 2017-02-08 / Inteligente. Tarifa Time-of-use tariffs are one way of encouraging consumers to carry out the transfer of load to off-peak intervals, thus making unnecessary new and high investments in generation and transmission and distribution infrastructure. This is therefore a tool for the expansion of energy efficiency, in a new concept of electricity grids, the Smart Grids. However, for this type of charging to be applied, new and modern meters are required, those with the capacity to differentiate consumption hours and that can inform the consumer properly. In this sense, this work is aimed at the development of a meter with an open source platform, in the case Arduino, associated to Analog Devices ADE7753 integrated circuit, transmitting information through IEEE802.11 (Wi-Fi) network, and through an IoT (Internet of Things) platform, to make an assessment whether adoption of the White Tariff is financially beneficial to the consumer in a simple and interactive way. / As tarifas hor?rias s?o uma das formas de incentivar os consumidores a realizarem a transfer?ncia de carga para intervalos fora de ponta, fazendo assim desnecess?rios novos e altos investimentos em gera??o e infraestrutura de transmiss?o e distribui??o. Sendo esta portanto uma ferramenta para a amplia??o da efici?ncia energ?tica, em um novo conceito de redes de energia el?trica, as Smart Grids. Entretanto, para que este tipo de tarifa??o seja aplicado, novos e modernos medidores s?o requeridos, aqueles com capacidade de diferencia??o de hor?rio de consumo e que possam informar devidamente ao consumidor. Neste sentido este trabalho visa o desenvolvimento de um medidor com plataforma open source, no caso o Arduino, associado ao circuito integrado para medi??o de energia el?trica ADE7753 da Analog Devices, transmitindo as informa??es atrav?s de rede IEEE802.11(Wi-Fi), e por meio de uma plataforma para IoT (Internet of Things), realizar uma avalia??o se a ado??o ? Tarifa Branca ? ben?fica financeiramente ao consumidor de forma simples e interativa.
34

Avaliação de critério pós-operatório de insuficiência hepática como fator prognóstico de mortalidade após hepatectomia: importância da alteração combinada do tempo de protrombina e da bilirrubina sérica / Evaluation of postoperative criteria of liver failure as a prognostic factor of mortality after hepatectomy: importance of the combined alteration of prothrombin time and serum bilirubin

Silvio Márcio Pegoraro Balzan 27 September 2006 (has links)
INTRODUÇÃO. A definição de insuficiência hepática pós-operatória (IHP) não é ainda padronizada, dificultando a comparação de inovações em procedimentos hepáticos e tornando complexo o uso de possíveis intervenções terapêuticas pós- operatórias em um momento adequado. CASUÍSTICA E MÉTODOS. Entre 1998 e 2002, 775 resecções hepáticas eletivas, dos quais 531 (69%) por doenças malignas e 464 (60%) consistindo em hepatectomias maiores, foram incluídas de maneira prospectiva em um banco de dados. O parênquima hepático não-tumoral foi anormal em 330 pacientes (43%) incluindo esteatose em mais que 30% dos hepatócitos em 107 (14%), fibrose sem cirrose em 237 (43%) e cirrose em 94 (12%). Foi analisado o impacto sobre a mortalidade da ocorrência de tempo de protrombina (TP) menor que 50% e bilirrubina total sérica (BT) maior que 50 µmol/L (3 mg/dl) (critério 50-50) nos dias pós-operatórios (PO) 1, 3, 5 e 7. RESULTADOS. A cinética pós-operatória do TP e da BT foram diferentes. O menor nível de TP foi no primeiro dia pós-operatório (PO) e o pico de BT foi no terceiro dia PO. A tendência ao retorno para valores pré-operatórios destes dois fatores bioquímicos se firmou claramente no quinto DPO. A mortalidade operatória global foi de 3.4% (26 pacientes), incluindo 21 (81%) casos com parênquima não-tumoral anormal e 20 (77%) após uma hepatectomia maior. O índice de mortalidade foi maior em pacientes com TP < 50% ou BT > 50 µmol/L (3 mg/dl) no pós-operatório. A conjunção de TP < 50% e BT > 50 µmol/L (3 mg/dl) no quinto DPO foi potente fator preditivo de mortalide, a qual atingiu 59% quando esta associação ocorreu. CONCLUSÕES. A partir do quinto dia PO, a associação de TP > 50% e BT > 50 µml/L (3 mg/dl) (critério 50-50) foi preditor prático e acurado de índice de mortalidade após hepatectomia. Propõe-se assim este critério como definição de insuficiência hepática pós-operatória. / INTRODUCTION. Definition of postoperative liver failure (PLF) is not standardized, rendering complex the comparison of novelties in liver procedures and also the use of possible postoperative therapeutic interventions in due time. METHODS. Between 1998 and 2002, 775 elective liver resections, whence 531 (69%) were for malignancies and 464 (60%) for major resections, were included in a prospective database. The non- tumorous hepatic parenchima was abnormal in 330 patients (43%) including steatosis > 30% in 107 (14%), non-cirrhotic fibrosis in 237 (43%) and cirrhosis in 94 (12%). The clinical impact of Prothrombin Time (PT) < 50% and Serum Bilirubin (SB) > 50µmol/L (3 mg/dl) (50-50 criteria) on postoperative days (POD) 1, 3, 5 and 7 was analyzed. RESULTS. Kinetic of postoperative PT and SB were different. Lowest PT levels were on POD1 and the peak of SB was on POD 3. The tendency to return to preoperative values of these two biochemical factors was clearly affirmed on POD 5. Operative mortality was 3.4% (26 patients), including 21 (81%) cases with abnormal liver parenchyma and 20 (77%) following major hepatectomies. Mortality rate was increased in patients with PT < 50% or SB > 50µmol/L (3mg/dl). The conjunction of PT < 50% and SB > 50µmol/L (3 mg/dl) on POD 5 was a strong predictive factor of increased mortality, which reached 59%. CONCLUSIONS We found that after postoperative day 5, the association of PT > 50% and SB > 50µml/L (3 mg/dl) (50-50 criteria) was a simple and accurate predictor of mortality after hepatectomy. These results allow us to propose this criteria as a definition of postoperative liver failure.
35

Machine learning based user activity prediction for smart homes

Goutham, Mithun January 2020 (has links)
No description available.
36

Optimum water distribution between pumping stations of multiple mine shafts / Nicolas Laurens Oosthuizen.

Oosthuizen, Nicolas Laurens January 2012 (has links)
In 2011 the mining industry purchased 14.5% of the electrical energy generated by Eskom. During 2011 in South Africa, dewatering pump systems on gold mines were the fourth largest electrical energy consumer on South African mines therefor making dewatering pumps ideal candidates to generate significant financial savings. These savings can be realised by controlling time-of-use (TOU) schedules. Previous studies concentrated on the impact of improving a pumping scheme of a single mineshaft. This dissertation will focus on the operations of a complete dewatering system consisting of multiple mineshafts. The case study will consist of a gold mine complex comprising of five different shafts - each with its own reticulation system – as well as the larger interconnected water reticulation system. Various pumping options were investigated, simulated and verified. The interaction between shafts was determined when load-shifting was scheduled for all the shafts taking each shaft’s particular infrastructure into account. The underground dewatering system was automated and optimised based on the simulation results. Mine safety protocols were adhered to while optimal pump operational schedules were introduced. / Thesis (MIng (Electrical and Electronic Engineering))--North-West University, Potchefstroom Campus, 2013.
37

Optimum water distribution between pumping stations of multiple mine shafts / Nicolas Laurens Oosthuizen.

Oosthuizen, Nicolas Laurens January 2012 (has links)
In 2011 the mining industry purchased 14.5% of the electrical energy generated by Eskom. During 2011 in South Africa, dewatering pump systems on gold mines were the fourth largest electrical energy consumer on South African mines therefor making dewatering pumps ideal candidates to generate significant financial savings. These savings can be realised by controlling time-of-use (TOU) schedules. Previous studies concentrated on the impact of improving a pumping scheme of a single mineshaft. This dissertation will focus on the operations of a complete dewatering system consisting of multiple mineshafts. The case study will consist of a gold mine complex comprising of five different shafts - each with its own reticulation system – as well as the larger interconnected water reticulation system. Various pumping options were investigated, simulated and verified. The interaction between shafts was determined when load-shifting was scheduled for all the shafts taking each shaft’s particular infrastructure into account. The underground dewatering system was automated and optimised based on the simulation results. Mine safety protocols were adhered to while optimal pump operational schedules were introduced. / Thesis (MIng (Electrical and Electronic Engineering))--North-West University, Potchefstroom Campus, 2013.
38

時間電價系統的最佳契約容量 / Optimal contract capacities for Time-of-Use electricity pricing systems

王家琪, Wang, Jia Qi Unknown Date (has links)
隨著各行各業的飛速發展、科技的不斷進步,一般的公司行號、工廠及現代化的建築對於電力需求大大增加。但是在有限的電力資源下,有時候一到用電高峰時期,很難滿足各行各業的用電需求,因此難免會出現很多地方在用電高峰期跳電的情況。電力公司為了更加有效的分配電力,提出所謂時間電價的概念,和用戶實現簽訂各自的契約容量,將這個契約容量作為每個月分配給各個用戶的最大電量標準。對於用戶來說,若選擇相對較低的契約容量,其所需要負擔的基本電費會較低。然而,當用電量超過契約容量時,用戶可能需要支付非常高額的罰款;若選擇相對較高的契約容量,雖然其支付高額罰款的機率會降低很多,但是所需要負擔的基本電費會增多。因此,對於電力公司和用戶而言,使用時間電價系統,來選擇一個適當的且最佳化的契約容量,已然成為一個非常重要的課題。本文介紹如何用分形布朗運動的模型,來描述用戶用電量趨勢,同時介紹了如何估計分形布朗運動模型中的各個參數。本文也介紹如何建立每月總電費期望值的估計方程式,並利用估計出來的用電量分形布朗運動模型來搜尋最佳化的契約容量。最後,本文以美國密西根州的安娜堡的居民住宅大樓用電量為數據資料作為研究的實例,進一步的提出並論證了選擇最佳化契約容量的方法。 / Over the last few decades, the advances in technology and industry have significantly increased the need of electric power, while the power resource is usually limited. In order to best control the power usage, a so-called Time-of-Use (TOU) pricing system is recently developed so that different rates over different seasons and/or weekly/daily peak periods are charged (this is different from the traditional pricing system with flat rate contracts). An important feature of the TOU system is that the consumers have to pre-select the power contract capacities (i.e. the maximum power demands claimed by consumers over different pricing periods) so that the electricity tariff can be calculated accordingly. This means that risk is transferred from the retailer side to the consumer side -- one has to pay more if a larger contract capacity is selected but can potentially mitigate the penalty charge placed when the maximum demand exceeds the contract level. In this thesis, a general stochastic modeling framework for consumer's power demand based on which the contract capacities of a Time-of-Use pricing system can be best selected so as to minimize the mean electricity price. Due to the observed nature of self-similarity and time dependence, the power demand over a homogeneous peak period is modeled as a constant mean with the noise described by a scaled fractional Brownian motion. However, the underlying optimization problem involves an intricate mathematical formulation, thus requiring techniques such as Monte Carlo simulation and numerical search so as to estimate the solution. Finally, a real data set from Ann Arbor, Michigan along with two pricing systems are used to illustrate our proposed method.
39

Net Positive Water

Ma, Billy January 2013 (has links)
‘Net Positive Water’ explores the capability of domestic architecture to combat the developing urban water problem. Urban intensification is contributing to the volatility of urban waters and the breakdown of the urban water cycle. Inhabitant water misuse and overconsumption is overwhelming aging municipal utilities, resulting in the decay of urban water quality. LEEDTM and The Living Building Challenge are recognized Green Building Guidelines prescribing sustainable site and building water standards. Case Studies of domestic Green Building projects will showcase water conservation to enable domestic water renewal. Net Zero Water Guidelines based on the Green Building Guidelines outline Potable and Non-Potable water use to achieve a sustainable volume of water demand at 70 litres per capita per day. Sustainable water practices are encouraged by utilizing domestic building systems to increase water value and water awareness. Time-of-Use and Choice-of-Use exposure for household water related tasks establish water savings through the use of best-performing water fixtures and appliances. Net Positive Water Guidelines will establish On-site and Building standards for sustainable harvesting and storage of water resources. Clean and Dirty water management will prescribe Passive design and Active mechanical processes to maintain best-available water quality in the urban domestic environment. Net Positive Water building typology will integrate urban inhabitation as a functional component of the urban water cycle to use, reuse, and renew water resources. The method will be tested using a Mid-rise Pilot project to deploy the necessary Passive and Active mechanisms to generate Net Positive Water quality through Net Zero Water sustainable water use. The pilot project is situated in Waterfront Toronto - The Lower Don Lands development to harness regional interests for water renewal and environmental revitalization.
40

Net Positive Water

Ma, Billy January 2013 (has links)
‘Net Positive Water’ explores the capability of domestic architecture to combat the developing urban water problem. Urban intensification is contributing to the volatility of urban waters and the breakdown of the urban water cycle. Inhabitant water misuse and overconsumption is overwhelming aging municipal utilities, resulting in the decay of urban water quality. LEEDTM and The Living Building Challenge are recognized Green Building Guidelines prescribing sustainable site and building water standards. Case Studies of domestic Green Building projects will showcase water conservation to enable domestic water renewal. Net Zero Water Guidelines based on the Green Building Guidelines outline Potable and Non-Potable water use to achieve a sustainable volume of water demand at 70 litres per capita per day. Sustainable water practices are encouraged by utilizing domestic building systems to increase water value and water awareness. Time-of-Use and Choice-of-Use exposure for household water related tasks establish water savings through the use of best-performing water fixtures and appliances. Net Positive Water Guidelines will establish On-site and Building standards for sustainable harvesting and storage of water resources. Clean and Dirty water management will prescribe Passive design and Active mechanical processes to maintain best-available water quality in the urban domestic environment. Net Positive Water building typology will integrate urban inhabitation as a functional component of the urban water cycle to use, reuse, and renew water resources. The method will be tested using a Mid-rise Pilot project to deploy the necessary Passive and Active mechanisms to generate Net Positive Water quality through Net Zero Water sustainable water use. The pilot project is situated in Waterfront Toronto - The Lower Don Lands development to harness regional interests for water renewal and environmental revitalization.

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