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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.
91

Contribuições ao estudo de implantação de pedágio urbano em São Paulo. / Contributions towards the study of congestion charging systems in São Paulo.

Dias, Felipe Ferreira 01 April 2015 (has links)
A Região Metropolitana de São Paulo (RMSP) sofre de sérios problemas de congestionamento, assim como muitas outras cidades de grande porte. Uma possível solução, proposta por pesquisadores de transportes, economia e ciências ambientais, é a implantação de um sistema de congestion charging, chamada no Brasil de pedágio urbano. Um dos objetivos do presente trabalho foi estabelecer os conceitos relacionados a este assunto e ilustrar as principais questões relacionadas à sua implantação. Espera-se que este trabalho possa auxiliar o desenvolvimento de estudos de avaliação da viabilidade e de impactos de sistemas propostos de congestion charging. Para atingir este objetivo, toca-se em diversos assuntos, como a definição de congestionamento e as formas de medi-lo, a base conceitual e teórica dos sistemas de congestion charging e seus diversos esquemas de diferenciação. São expostas também as medidas de mitigação de congestionamento que já foram implantadas na RMSP, quais foram os estudos já desenvolvidos considerando este tipo de política para a RMSP, e casos em que sistemas de congestion charging já foi implantado. Neste trabalho, desenvolveu-se também um modelo de escolha discreta a partir dos dados da Pesquisa Origem e Destino 2007 do METRÔ, onde pessoas deveriam escolher entre \"Transporte Coletivo\" e \"Transporte Público\". Este modelo foi utilizado para avaliar o potencial de impacto na divisão modal e de arrecadação de um congestion charge aplicado ao centro expandido de São Paulo. Adverte-se, porém, que os resultados obtidos são meramente ilustrativos. Mostra-se, também, que é possível avaliar a capacidade ociosa do sistema de transporte coletivo a partir dos dados disponíveis de bilhetagem e de GPS dos ônibus. Este processo é exemplificado através do cálculo de capacidade de uma única viagem de um único ônibus, dada a dificuldade de automatização deste processo para abranger toda a frota. / The São Paulo Metropolitan Region (SPMR) suffers from severe traffic congestion, as do many other large-scale urban areas around the world. A possible solution to this issue, which has been suggested by transportation, economics and environmental researchers, is the implementation of a congestion charging system. One of the objectives of this project is to establish clear concepts and shed light on the main issues regarding these systems by means of a comprehensive literary review. It is expected that this project may help the development of in-depth studies carried in order to evaluate the viability and impacts of congestion charging proposals. In order to achieve this goal, many subjects are addressed, such as the definition of congestion, how its measured, the theoretical backgrounds that support congestion charging schemes, their different degrees of differentiation, which policies were enacted in order to reduce traffic congestion in São Paulo, what considerations and studies have already been developed for Brazil and São Paulo regarding these systems and where have these systems been successfully installed. Later chapters deal with another goal of this project: estimating how a congestion charging system would affect SPMR. This was achieved through a multinomial logit model, where decision-makers choose between \"Public Transportation\" and \"Private Automobile\". The results presented at this phase are merely indicative of certain tendencies and should not be considered final. This project also attempts to show that given the available Automated Fare Collection (AFC) data and Automated Vehicle Location (AVL) data, it is possible to estimate the current public transportation system\'s unused capacity. The author shows this by calculating the capacity of one bus trip using these data, but also explains the difficulties of expanding this analysis to the whole of SPMR\'s public transportation system.
92

Improved mine cooling system performance through the control of auxiliary systems / W. Bornman

Bornman, Waldo January 2012 (has links)
Industrial and mining sectors are amongst the largest single energy consumers in South Africa, making them a primary focus for implementing energy saving initiatives. Refrigeration systems on mines are responsible for consuming up to25 % of the electrical energy consumption on a typical South African deep level mine. Ample opportunities to reduce the energy consumption of these systems exists, as many of the current systems rely on old technology and function under partial or inadequate control management. In compiling this thesis, various energy saving strategies on deep level mines were investigated. In specific, the effects of controlling and improving the cooling auxiliaries. Scenarios were investigated and simulated, where after an optimum solution was implemented. Implementations, such as the ones covered in this dissertation, form part of the IDM (Integrated Demand Management) energy efficiency incentive introduced by Eskom, where funding is made available based on actual power saving; ensuring that the projects will be financially viable to the clients. Reduced electrical energy consumption realised from the abovementioned projects were measured, captured and compared to the consumption before project implementation to determine the achieved savings. Savings of up to 30 % of the plant installed capacity were realised, providing average savings of up to 2.3 MW per day. / Thesis (MIng (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2013
93

Improved mine cooling system performance through the control of auxiliary systems / W. Bornman

Bornman, Waldo January 2012 (has links)
Industrial and mining sectors are amongst the largest single energy consumers in South Africa, making them a primary focus for implementing energy saving initiatives. Refrigeration systems on mines are responsible for consuming up to25 % of the electrical energy consumption on a typical South African deep level mine. Ample opportunities to reduce the energy consumption of these systems exists, as many of the current systems rely on old technology and function under partial or inadequate control management. In compiling this thesis, various energy saving strategies on deep level mines were investigated. In specific, the effects of controlling and improving the cooling auxiliaries. Scenarios were investigated and simulated, where after an optimum solution was implemented. Implementations, such as the ones covered in this dissertation, form part of the IDM (Integrated Demand Management) energy efficiency incentive introduced by Eskom, where funding is made available based on actual power saving; ensuring that the projects will be financially viable to the clients. Reduced electrical energy consumption realised from the abovementioned projects were measured, captured and compared to the consumption before project implementation to determine the achieved savings. Savings of up to 30 % of the plant installed capacity were realised, providing average savings of up to 2.3 MW per day. / Thesis (MIng (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2013
94

Contribuições ao estudo de implantação de pedágio urbano em São Paulo. / Contributions towards the study of congestion charging systems in São Paulo.

Felipe Ferreira Dias 01 April 2015 (has links)
A Região Metropolitana de São Paulo (RMSP) sofre de sérios problemas de congestionamento, assim como muitas outras cidades de grande porte. Uma possível solução, proposta por pesquisadores de transportes, economia e ciências ambientais, é a implantação de um sistema de congestion charging, chamada no Brasil de pedágio urbano. Um dos objetivos do presente trabalho foi estabelecer os conceitos relacionados a este assunto e ilustrar as principais questões relacionadas à sua implantação. Espera-se que este trabalho possa auxiliar o desenvolvimento de estudos de avaliação da viabilidade e de impactos de sistemas propostos de congestion charging. Para atingir este objetivo, toca-se em diversos assuntos, como a definição de congestionamento e as formas de medi-lo, a base conceitual e teórica dos sistemas de congestion charging e seus diversos esquemas de diferenciação. São expostas também as medidas de mitigação de congestionamento que já foram implantadas na RMSP, quais foram os estudos já desenvolvidos considerando este tipo de política para a RMSP, e casos em que sistemas de congestion charging já foi implantado. Neste trabalho, desenvolveu-se também um modelo de escolha discreta a partir dos dados da Pesquisa Origem e Destino 2007 do METRÔ, onde pessoas deveriam escolher entre \"Transporte Coletivo\" e \"Transporte Público\". Este modelo foi utilizado para avaliar o potencial de impacto na divisão modal e de arrecadação de um congestion charge aplicado ao centro expandido de São Paulo. Adverte-se, porém, que os resultados obtidos são meramente ilustrativos. Mostra-se, também, que é possível avaliar a capacidade ociosa do sistema de transporte coletivo a partir dos dados disponíveis de bilhetagem e de GPS dos ônibus. Este processo é exemplificado através do cálculo de capacidade de uma única viagem de um único ônibus, dada a dificuldade de automatização deste processo para abranger toda a frota. / The São Paulo Metropolitan Region (SPMR) suffers from severe traffic congestion, as do many other large-scale urban areas around the world. A possible solution to this issue, which has been suggested by transportation, economics and environmental researchers, is the implementation of a congestion charging system. One of the objectives of this project is to establish clear concepts and shed light on the main issues regarding these systems by means of a comprehensive literary review. It is expected that this project may help the development of in-depth studies carried in order to evaluate the viability and impacts of congestion charging proposals. In order to achieve this goal, many subjects are addressed, such as the definition of congestion, how its measured, the theoretical backgrounds that support congestion charging schemes, their different degrees of differentiation, which policies were enacted in order to reduce traffic congestion in São Paulo, what considerations and studies have already been developed for Brazil and São Paulo regarding these systems and where have these systems been successfully installed. Later chapters deal with another goal of this project: estimating how a congestion charging system would affect SPMR. This was achieved through a multinomial logit model, where decision-makers choose between \"Public Transportation\" and \"Private Automobile\". The results presented at this phase are merely indicative of certain tendencies and should not be considered final. This project also attempts to show that given the available Automated Fare Collection (AFC) data and Automated Vehicle Location (AVL) data, it is possible to estimate the current public transportation system\'s unused capacity. The author shows this by calculating the capacity of one bus trip using these data, but also explains the difficulties of expanding this analysis to the whole of SPMR\'s public transportation system.
95

Programas permanentes de uso racional da água em campi universitários: o Programa de Uso Racional da Água da Universidade de São Paulo. / Permanent water conservation programs in university campi: the Water Conservation Program of the University of São Paulo.

Silva, Gisele Sanches da 09 March 2005 (has links)
No contexto da crescente problemática da água, soluções em diferentes níveis têm sido adotadas no Brasil e no mundo. Exemplo de atuação no nível dos sistemas prediais, o uso racional da água tem sido objeto de diversos estudos. Neste trabalho, são avaliados, segundo uma abordagem sistêmica, as atividades a serem contempladas na implementação de Programas Permanentes de Uso Racional da Água, especialmente em campi universitários, e seus potenciais resultados. Características dos campi como área, número de edificações, população e consumo de água elevados, além do desenvolvimento de múltiplas atividades, demonstram sua importância e justificam a atenção. São avaliadas, portanto, as atividades de planejamento, pré-implantação, implantação e pós-implantação, além das atividades de gestão da demanda de água, que devem permear todo o Programa. Como resultado desta implementação estruturada, propõe-se, como impactos - a redução do consumo de água, e como efeitos - alterações no sistema de suprimento de água fria, em rotinas administrativas e de manutenção predial, e em parâmetros de projeto; desenvolvimento tecnológico dos equipamentos; despertar para a conservação da água; e mudanças comportamentais dos usuários. A implementação e os resultados do Programa de Uso Racional da Água da Universidade de São Paulo (PURA-USP) completam o trabalho. Em desenvolvimento desde 1998, o PURA-USP obteve, como impactos até 2003, uma redução no consumo de água de 36% (de 137.881 para 88.366 m³/mês) e um benefício líquido acumulado de R$ 46,61 milhões. / In the context of the increasing water issues concerns, solutions at different levels have been adopted in Brazil and worldwide. As an example of actuation at the building systems level, water conservation has been the object of several studies. In this work, the activities to be fulfilled in the implementation of a Permanent Water Conservation Program, specially when applied to university campi, as well as the possible results are evaluated under a system approach. Campi characteristics such as area, number of buildings, population, and high water consumption, besides the development of multiple activities, show the importance of this issue and justify the concerns. The Program planning, pre-implantation, implantation and post-implantation activities, besides the water demand management activities - that must be carried out throughout the program - are evaluated then. As results of this structured implementation, it is proposed as impacts - the water consumption reduction, and as effects - the changes in the water supply systems, in administrative and building maintenance routines, in design parameters, in the technological development of fixtures, in the awakening for the alternatives water sources, and in the users behavior. The implementation and the results of the Water Conservation Program of the University of São Paulo (Programa de Uso Racional da Água da Universidade de São Paulo - PURA-USP) finish the work. The PURA-USP, in development since 1998, achieved as impacts, until 2003, 36% of water consumption reduction (from 137,881 to 88,366 m³/month) and gathered net benefit of US$ 16.13 millions (R$ 46,61 milhões).
96

A medição setorizada como instrumento de gestão da demanda de água em sistemas prediais - estudo de caso: Programa de Uso Racional da Água da Universidade de São Paulo. / Submetering as an instrument of water demand management in building systems – case study: Water Conservation Program of the University of São Paulo.

Tamaki, Humberto Oyamada 03 April 2003 (has links)
No presente trabalho é estudada a utilização da medição setorizada como instrumento de gestão da demanda de água em sistemas prediais. Para tanto, a caracterização dos medidores e a análise das interações dos elementos de medição com o sistema de suprimento de água fria e de equipamento sanitário são realizados a partir de um enfoque sistêmico e de desempenho. Considerando a coleta de melhores informações, qualitativamente e quantitativamente acerca do consumo, essencial para a gestão da demanda de água, e especialmente em um contexto de ações de conservação, neste trabalho levantou-se os sistemas de telemedição. Apresentou-se uma proposta de planejamento de implantação da medição setorizada e quais elementos que devem ser observados para a gestão da demanda. Para subsidiar as avaliações, realizou-se o estudo de caso da medição setorizada na Universidade de São Paulo, no qual foi possível verificar a importância da sua aplicação e os resultados extremamente positivos que justificaram sua implantação. / In this work it is studied the use of submetering as an instrument of water demand management in building systems. In such way, the characterization of the meters and the analysis of the interactions of its elements with the building hydraulical system are carried on a systemic approach and performance analysis of the proposal. Considering the collection of better information of water consumption essential for the water demand management, especially in a conservation context, it was searched out the systems and the technologies of remote metering. A proposal for the planning of the submetering implantation was showed, as well as the elements that should be considered for the demand management. To make the evaluations, the case study of the submetering program in the University of São Paulo was accomplished, in which it was possible to verify the importance of its application and the extremely positive results that had justified its implantation.
97

Uma contribuição para a formalização do processo de gestão da demanda no âmbito do planejamento e controle da produção de empresas MTS (Make-To-Stock) / not available

Santa Eulalia, Luis Antonio de 21 December 2001 (has links)
No atual contexto do planejamento e controle da produção, existe uma necessidade de uma melhor utilização do processo de negócio que norteia o desenvolvimento de todos os seus planos, conhecido como gestão da demanda. Nesse assunto, a existência de literatura adequada e de modelos ou formalismos que visam facilitar a compreensão e utilização do processo em si, é rara, e por muitas vezes, insuficiente. Dessa forma, a gestão da demanda acaba por não ser amplamente conhecida, e, por conseqüência, torna-se sub-utilizada nas organizações. Assim, este trabalho visa colaborar para a solução dessa questão, contribuindo para a geração de um modelo formal que possa ser útil tanto à comunidade acadêmica quanto à empresarial interessada. / In current context of the Manufacturing Planning and Control Systems there is a need for a better use of the business process that address the development of alI its plans, the Demand Management process. The existence of appropriate literature and models or formalisms that aims to help a better understanding and usage of this business process is rare and insufficient. ln that way, the Demand Management process is not being known thoroughly and, for consequence, it is not properly used in some organizations. Thus, this work aims to collaborate for the solution of this problem, contributing to a formal model generation that can be useful for the academic and managerial community interested.
98

Rainwater harvesting for drought mitigation and flood management

Melville-Shreeve, Peter January 2017 (has links)
Rainwater harvesting (RWH) in the UK has seen a low level of uptake relative to similar settings such as Australia and Germany. The relatively low cost of municipal water in the UK limits the financial savings associated with RWH systems, especially in a domestic setting. Although financial benefits can be relatively low (in terms of reduced water bills), academic and practitioner studies have demonstrated the potential for RWH to significantly reduce potable water demands at typical UK houses. Hence, increased uptake of RWH has potential to contribute to mitigating droughts in water scarce regions. Stormwater management in the UK is receiving increasing attention at all levels; from grass-roots sustainable drainage systems (SuDS) such as downpipe disconnections and raingardens; through to implementation of urban realm attenuation schemes and continued development of guidance from UK policy makers. The public realm nature of most SuDS presents a need for partnership approaches to be fostered between infrastructure mangers and the general public. The application of RWH as a technology within the SuDS management train has been limited in the UK as policy makers have taken the view that RWH tanks may be full at the start of a design storm, and thus the potential for attenuation and peak discharge reduction has been largely ignored. However, in the last few years there has been a shift in emphasis; from RWH perceived purely as a water demand management technology to a focus on its wider benefits e.g. mitigating surface water flooding through improved stormwater management. RWH systems examined in this thesis are now available which offer multiple benefits to both end-users and water service providers. The application of RWH in a dual purpose configuration (to displace potable water demands and control stormwater discharges) has seen increasing interest during the development of this thesis. However, the successful design of RWH as a stormwater management tool requires a series of calculations to be completed. To date, practitioners have frequently relied upon low-resolution heuristic methods which lead to a small range of configurations being deployed, with minimal demonstrable stormwater control benefits. In this thesis, full details of novel and traditional RWH technologies were identified and described. Empirical data was collected, both in laboratory conditions and at field sites, to identify the real world operating characteristics of a range of RWH configurations. Additionally a new time series evaluation methodology was developed to enable RWH systems to be designed and analysed. This method quantifies water demand benefits and also focusses on stormwater management metrics (i.e. largest annual discharge and total discharge volume per year). The method was developed to enable a range of RWH configurations to be evaluated at a given site. In addition, a decision support tool (RainWET) was developed and tested which enabled the methods to be deployed in real world settings. The application of the RainWET software allowed a UK-wide, time series analysis of RWH configurations to be completed and the holistic benefits of a range of dual purpose RWH systems to be analysed and described. Evidence from the UK study suggests that a traditional RWH installation (3000l storage, 300l/day demand and 60m2 roof) installed at a house in a water scarce region (London, SAAR 597mm) was able to fully mitigate stormwater overflows over a 20 year analysis whilst providing a mean water saving of 31,255l/annum. An equivalent system located in the wettest region studied (Truro, SAAR 1099mm) saw mean reductions in the largest annual storm of 62% (range 35-86%) whilst satisfying a mean rainwater demand of 50,912l/annum. The study concluded that suitably designed dual purpose RWH systems offered better stormwater management benefits than those designed without a stormwater control device. In addition, the integration of smart RWH controls were shown to maximise stormwater control benefits with little or no reduction in a system’s ability to satisfy non-potable water demands.
99

Municipal water supply governance in Ontario: neoliberalization, utility restructuring, and infrastructure management

Furlong, Kathryn 05 1900 (has links)
This thesis examines the interaction of political-economic restructuring, sustainability, and the governance of municipal services in the province of Ontario, Canada. Two issues are studied: the restructuring of business models, and programs for sustainable infrastructure management (focusing on programs for the reduction of water consumption and production). The primary data are derived from a province-wide expert survey, archival research, a one-day expert workshop, and seven municipal case studies. Since the early 1990s, political-economic restructuring in Ontario predominantly reflects processes and policy orientations consistent with neoliberalization. Two strands of research posit particular relationships between neoliberalization and sustainability. One (associated with political ecology) asserts that neoliberalization yields negative outcomes for environmental policy. The other (ecological modernization) asserts that neoliberal restructuring leads to environmental improvements. This thesis tests and complicates both sets of claims. Specifically, neoliberalization does not necessarily induce improved programming for sustainability and can, hinder its development. Neoliberalization, however, is not the unique hindrance to progress on sustainability. Rather, a techno-physical approach to service delivery combined with governance arrangements that neither empower nor compel a variety of necessary actors presents a key barrier to sustainability. In terms of the restructuring of business models, I find that the primary neoliberal strategy is the depoliticization of governance through the pursuit of arms length business models for service delivery. This, however, is not readily accomplished in complete or straightforward ways. Municipal governments and anti-neoliberal alliances have complex relationships to neoliberalization that prove important in restructuring outcomes. Specifically, neoliberalization is also contested within municipal government and for environmental advocates, although their best option, the municipal department model remains unsatisfactory. Concerning sustainable infrastructure management, the thesis finds that up-take of supply and demand management in Ontario has been limited to date. This results from incentives created by policy processes associated with neoliberalization (specifically new public management) and technically-driven management methods in the water sector. Moreover, where programs for sustainable infrastructure management currently occur, they are rarely motivated by sustainability concerns. Importantly, however, sustainable infrastructure management is underdeveloped for reasons other than neoliberalization; governance arrangements and the continuing supply-side orientation of water utilities are other factors.
100

Innovative policies to manage demand in service systems with limited capacity

Phumchusri, Naragain 10 November 2010 (has links)
This dissertation presents innovative demand management techniques for service systems with limited resources. The first study analyzes demand management policies of animal shelters with limited Kennel space as a set of interacting stochastic queueing systems. In practice, there are two main policies being used, which we call "Kill" and "No-Kill" policies. In a "Kill" system, animals may be euthanized if a shelter is full. Many shelters have moved to a "No-Kill" policy, where they avoid killing for space and adopt other approaches to reduce supply and demand mismatch. Our goal is to provide insights on how No-Kill policies, such as coordination, adoption and neutering campaigns, help reduce the animals' killing rate so that the shelter management can choose the way to effectively solve their problems. In the second part, we consider a topic of demand management for the Sports and Entertainment (S&E) industry, called "Scaling the house", i.e., how to divide seats into zones for different prices to maximize revenue across the venue. From the data obtained from several performance venues in the U.S., we find ticket demand is impacted by locations of seats as well as by price. We characterize closed-form solutions for the optimal two-dimensional zoning decision (with row and column cuts) and the one-dimensional decision (with row cuts), and explore when each model should be applied. The third study considers pricing as a tool to manage demand for the S&E tickets. We develop dynamic pricing with demand learning models where demand is also affected by time left until the show dates. Since the show's popularity is usually uncertain to the seller, we propose a method to learn the overall popularity via Bayesian updates. We perform computational experiments to understand properties of the model solutions and identify when demand learning is most beneficial.

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