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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.
101

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.
102

Extracting airline and passenger behavior from online distribution channels: applications using online pricing and seat map data

Mumbower, Stacey M. 20 September 2013 (has links)
Although the airline industry has drastically changed since its deregulation in 1978, publically available sources of data have remained nearly the same. In the U.S., most researchers and decision-makers rely on government data that contains highly aggregated price information (e.g., average quarterly prices). However, aggregate data can hide important market behavior. With the emergence of online distribution channels, there is a new opportunity to model air travel demand using detailed price information. This dissertation uses online prices and seat maps to build a dataset of daily prices and bookings at the flight-level. Several research contributions are made, all related to leveraging online data to better understand airline pricing and product strategies, and how these strategies impact customers, as well as the industry in general. One major contribution is the finding that the recent product debundling trend in the U.S. airline industry has diluted revenues to the U.S. Airport and Airways Trust Fund by at least five percent. Additionally, several new behavioral insights are found for one debundling trend that has been widely adopted by U.S. airlines: seat reservation fees. Customers are found to be between 2 and 3.3 times more likely to purchase premium coach seats (with extra legroom and early boarding privileges) when there are no regular coach window or aisle seats that can be reserved for free, suggesting that the ability of airlines to charge seat fees is strongly tied to load factors. Model results are used to explore optimal seat fees and find that an optimal static fee could increase revenues by 8 percent, whereas optimal dynamic fees could increase revenues by 10.2 percent. Another major contribution is in modeling daily bookings and estimating price elasticities using ordinary least squares (OLS) regression without correcting for price endogeneity and two-stage least squares (2SLS) regression, which corrects for endogeneity. Results highlight the importance of correcting for price endogeneity (which is not often done in air travel applications). In particular, models that do not correct for endogeneity find inelastic demand estimates whereas models that do correct for endogeneity find elastic demand estimates. This is important, as pricing recommendations differ for inelastic and elastic models. A set of instrumental variables are found to pass validity tests and can be used to correct for price endogeneity in future models of daily flight-level demand.
103

Urban Water Security – Local Conditions and Regional Context : A case study of attitudes and water use behaviour in Windhoek, Namibia

Sjömander Magnusson, Therése January 2005 (has links)
The world is becoming urbanised. Between 1995 and 2025, it is estimated that the cities and towns of the developing world will have absorbed another two billion people. A majority of these people will be poor and settle down in the unregulated areas. It is therefore fair to say that the management and use of water in urban areas is a very complex and dynamic issue. The fact that cities in the South are composed of two systems, the regulated and the unregulated areas, and that considerable diversity exists between them, highlights the need for a context driven policy design in urban water management. For attaining urban water security in these cities, controlling water demand in the regulated areas while improving access to water of good quality in the unregulated areas must be a priority. This thesis is based on a case study of Windhoek, a city characterized by conditions of aridity, rapid urbanisation and primate city dominance. Since 1994, a thorough water demand management (WDM) strategy has been implemented in Windhoek, aiming at improving water use efficiency and to reduce water consumption through economic and non-economical measures. It has been the purpose to examine the development of urban water management along with urban growth, the response to WDM by the domestic and private business sectors, as well as challenges and benefits of allowing urban branch-lines along water transfer schemes. WDM can be an efficient tool in the struggle against luxury and non-efficient water use, to postpone bulk water investments and for cost-recovery. However, it is crucial that the incentives are based on and flexible according to socio-economic conditions, and that water managers acknowledge motives and attitudes that shape water use behaviour. One dilemma of WDM lies in the fact that if the supply capacity is increased, it is likely that demand will be adjusted accordingly. It is a tricky task to motivate water savings through demand management alongside with an improved water supply. Moreover, it is essential that savings are not only temporary, but also part of a long-term adjustment. Another predicament of WDM is that a high trust in water authorities actually lowered the efficiency of the strategy to meet the anticipated goal.
104

A system-of-systems modeling methodology for strategic general aviation design decision-making

Won, Henry Thome 17 November 2008 (has links)
A methodology for modeling general aviation transportation systems from a system of systems perspective is presented. The completed framework aids the conceptual design process by providing capability-based metrics to the design engineer, as opposed to the traditional performance and cost, system-level metrics. The methodology is applied to two example problems representing promising future general aviation aircraft: the general aviation piston (GAP) and jet (GAJ). Results are presented in an array of formats, and the decision-making strategies that are now apparent in light of the capability-based metrics are described. The findings suggest that the system of systems framework might act as an analytical surrogate to the conventional problem definition process, providing indications of market preferences when that information is not immediately available through the conventional means. Implementation of this methodology can afford engineers a more autonomous perspective in the concept exploration process, providing dynamic feedback about a design's potential success in specific market segments. The method also has potential to strengthen the connection between design and business departments, as well as between manufacturers, service providers, and infrastructure planners - bringing information about how the respective systems interact, and what might be done to improve synergism of systems.
105

A design methodology for evolutionary air transportation networks

Yang, Eunsuk 18 May 2009 (has links)
The air transportation demand at large hubs in the U.S. is anticipated to double in the near future. Current runway construction plans at selected airports can relieve some capacity and delay problems, but many are doubtful that this solution is sufficient to accommodate the anticipated demand growth in the National Airspace System (NAS). With the worsening congestion problem, it is imperative to seek alternative solutions other than costly runway constructions. In this respect, many researchers and organizations have been building models and performing analyses of the NAS. However, the complexity and size of the problem results in an overwhelming task for transportation system modelers. This research seeks to compose an active design algorithm for an evolutionary airline network model so as to include network specific control properties. An airline network designer, referred to as a network architect, can use this tool to assess the possibilities of gaining more capacity by changing the network configuration. Since the Airline Deregulation Act of 1978, the airline service network has evolved from a point-to-point into a distinct hub-and-spoke network. Enplanement demand on the H&S network is the sum of Origin-Destination (O-D) demand and transfer demand. Even though the flight or enplanement demand is a function of O-D demand and passenger routings on the airline network, the distinction between enplanement and O-D demand is not often made. Instead, many demand forecast practices in current days are based on scale-ups from the enplanements, which include the demand to and from transferring network hubs. Based on this research, it was found that the current demand prediction practice can be improved by dissecting enplanements further into smaller pieces of information. As a result, enplanement demand is decomposed into intrinsic and variable parts. The proposed intrinsic demand model is based on the concept of 'true' origin-destination demand which includes the direction of each round trip travel. The result from using true O-D concept reveals the socioeconomic functional roles of airports on the network. Linear trends are observed for both the produced and attracted demand from the data. Therefore, this approach is expected to provide more accurate prediction capability. With the intrinsic demand model in place, the variable part of the demand is modeled on an air transportation network model, which is built with accelerated evolution scheme. The accelerated evolution scheme was introduced to view the air transportation network as an evolutionary one instead of a parametric one. The network model takes in intrinsic demand data before undergoing an evolution path to generate a target network. The results from the network model suggests that air transportation networks can be modeled using evolutionary structure and it was possible to generate the emulated NAS. A dehubbing scenario study of Lambert-St. Louis International Airport demonstrated the prediction capability of the proposed network model. The overall process from intrinsic demand modeling and evolutionary network modeling is a unique and it is highly beneficial for simulating active control of the transportation networks.
106

Impactos da implantação de medidas de gerenciamento da mobilidade em uma área urbana com múltiplos pólos atratores de viagens

Schmitt, Rafael da Silva January 2006 (has links)
Nesta dissertação são analisados os impactos da implantação de medidas de gerenciamento da mobilidade (GM) em uma área urbana localizada na cidade de Porto Alegre com vários pólos atratores de viagens. O GM – abordagem européia do gerenciamento da demanda de viagens – busca uma mobilidade urbana mais sustentável, tentando influir no comportamento de viagem das pessoas. São discutidos seu conceito, suas ferramentas, medidas e serviços de transporte, incluindo exemplos de implantação no mundo. Foram escolhidas duas medidas de GM, dentro de um pacote de medidas a serem implantadas pelo projeto Moviman na área de estudo, localizada na zona leste de Porto Alegre, onde atualmente há uma universidade (PUCRS), hospitais, um shopping center, hipermercados, entre outros estabelecimentos. A primeira medida analisada foi a carona programada, uso compartilhado de um automóvel com divisão de custos. Foi feita uma pesquisa com alunos da PUCRS para verificar sua receptividade em relação a esta medida. A partir dos resultados desta pesquisa, foi avaliado o possível impacto da implantação desta medida no tráfego da área de estudo. Também foi feita pesquisa com trabalhadores de uma empresa local para comparar a receptividade a esta medida por usuários diferentes. A segunda medida foi a implantação de um Sistema de Informação ao Usuário (SIU) de transporte coletivo em duas paradas de ônibus, através da realização de pesquisas de importância e satisfação, para priorizar as informações e de uma pesquisa final de satisfação e análise de intenção de mudança modal causada pelo SIU. Os resultados demonstram que a carona programada é uma medida com boa receptividade entre os grupos-alvo pesquisados, que causa uma melhora das condições de tráfego locais. E um novo SIU nas paradas de ônibus é uma medida de qualificação do transporte coletivo com um bom potencial de atração de novos usuários e de fidelização dos atuais. Portanto, comprovouse o impacto positivo da implantação destas medidas de GM em uma cidade brasileira, pois ambas atenderam aos objetivos de uma mobilidade urbana sustentável sem a limitação da mobilidade das pessoas. / This dissertation presents the evaluation of the impacts produced by mobility management (MM) measures introduced in an urban area, with many trip production centers, located in Porto Alegre city, southern Brazil. The MM, European approach of travel demand management, aims a more sustainable urban mobility, trying to influence in the travel behavior of people. Their concepts, tools, measures and transport services are discussed, including other implantation examples worldwide. Two MM measures were chosen within a package of measures that would be implemented by the Moviman project in the studied area. The selected area, situated in the east zone of Porto Alegre, holds a university (PUCRS), hospitals, a shopping center, among others commercial establishments. The first analyzed measure was carpooling, shared use of an automobile with division of costs, using the application of a survey with university students, from PUCRS, to verify their receptivity in relation to this alternative transportation mode. The survey results were used for the analysis of possible impacts of this measure in the traffic of the study area. A survey with workers of a local company was done to compare the receptivity with these measures in distinct users. The second measure was the installation of a public transport user information system (UIS) in two bus stops, using importance and satisfaction surveys in order to define information priorities, and a final survey of satisfaction and analysis of modal change intention caused by UIS. The results demonstrate that carpooling is a transport measure with good receptivity among the target groups, and improves the local traffic conditions. Moreover the installation of new UIS in bus stops is a measure of qualification of the public transportation with good potential for attraction of new users and consolidation of actual users. Therefore, the impacts of MM measures in a Brazilian city were positive, considering that both measures reach the goal of sustainable mobility without limiting people mobility.
107

Impactos da implantação de medidas de gerenciamento da mobilidade em uma área urbana com múltiplos pólos atratores de viagens

Schmitt, Rafael da Silva January 2006 (has links)
Nesta dissertação são analisados os impactos da implantação de medidas de gerenciamento da mobilidade (GM) em uma área urbana localizada na cidade de Porto Alegre com vários pólos atratores de viagens. O GM – abordagem européia do gerenciamento da demanda de viagens – busca uma mobilidade urbana mais sustentável, tentando influir no comportamento de viagem das pessoas. São discutidos seu conceito, suas ferramentas, medidas e serviços de transporte, incluindo exemplos de implantação no mundo. Foram escolhidas duas medidas de GM, dentro de um pacote de medidas a serem implantadas pelo projeto Moviman na área de estudo, localizada na zona leste de Porto Alegre, onde atualmente há uma universidade (PUCRS), hospitais, um shopping center, hipermercados, entre outros estabelecimentos. A primeira medida analisada foi a carona programada, uso compartilhado de um automóvel com divisão de custos. Foi feita uma pesquisa com alunos da PUCRS para verificar sua receptividade em relação a esta medida. A partir dos resultados desta pesquisa, foi avaliado o possível impacto da implantação desta medida no tráfego da área de estudo. Também foi feita pesquisa com trabalhadores de uma empresa local para comparar a receptividade a esta medida por usuários diferentes. A segunda medida foi a implantação de um Sistema de Informação ao Usuário (SIU) de transporte coletivo em duas paradas de ônibus, através da realização de pesquisas de importância e satisfação, para priorizar as informações e de uma pesquisa final de satisfação e análise de intenção de mudança modal causada pelo SIU. Os resultados demonstram que a carona programada é uma medida com boa receptividade entre os grupos-alvo pesquisados, que causa uma melhora das condições de tráfego locais. E um novo SIU nas paradas de ônibus é uma medida de qualificação do transporte coletivo com um bom potencial de atração de novos usuários e de fidelização dos atuais. Portanto, comprovouse o impacto positivo da implantação destas medidas de GM em uma cidade brasileira, pois ambas atenderam aos objetivos de uma mobilidade urbana sustentável sem a limitação da mobilidade das pessoas. / This dissertation presents the evaluation of the impacts produced by mobility management (MM) measures introduced in an urban area, with many trip production centers, located in Porto Alegre city, southern Brazil. The MM, European approach of travel demand management, aims a more sustainable urban mobility, trying to influence in the travel behavior of people. Their concepts, tools, measures and transport services are discussed, including other implantation examples worldwide. Two MM measures were chosen within a package of measures that would be implemented by the Moviman project in the studied area. The selected area, situated in the east zone of Porto Alegre, holds a university (PUCRS), hospitals, a shopping center, among others commercial establishments. The first analyzed measure was carpooling, shared use of an automobile with division of costs, using the application of a survey with university students, from PUCRS, to verify their receptivity in relation to this alternative transportation mode. The survey results were used for the analysis of possible impacts of this measure in the traffic of the study area. A survey with workers of a local company was done to compare the receptivity with these measures in distinct users. The second measure was the installation of a public transport user information system (UIS) in two bus stops, using importance and satisfaction surveys in order to define information priorities, and a final survey of satisfaction and analysis of modal change intention caused by UIS. The results demonstrate that carpooling is a transport measure with good receptivity among the target groups, and improves the local traffic conditions. Moreover the installation of new UIS in bus stops is a measure of qualification of the public transportation with good potential for attraction of new users and consolidation of actual users. Therefore, the impacts of MM measures in a Brazilian city were positive, considering that both measures reach the goal of sustainable mobility without limiting people mobility.
108

Gerencimento da demanda: um survey na cadeia de suprimentos automotiva brasileira / Demand management: a survey in the brazilian automotive supply chain

Esteves, Mario Augusto Matos Simon [UNESP] 21 October 2016 (has links)
Submitted by MARIO AUGUSTO MATOS SIMON ESTEVES (marioaugustoesteves@gmail.com) on 2016-12-21T01:17:05Z No. of bitstreams: 1 Dissertacao de Mestrado - Mario Esteves - Final.pdf: 3642994 bytes, checksum: 14617df83472dcb04e1f218abfd26cd4 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-12-22T12:43:08Z (GMT) No. of bitstreams: 1 esteves_mams_me_guara.pdf: 3642994 bytes, checksum: 14617df83472dcb04e1f218abfd26cd4 (MD5) / Made available in DSpace on 2016-12-22T12:43:08Z (GMT). No. of bitstreams: 1 esteves_mams_me_guara.pdf: 3642994 bytes, checksum: 14617df83472dcb04e1f218abfd26cd4 (MD5) Previous issue date: 2016-10-21 / Com o contínuo crescimento da competitividade global, o grande desafio é trabalhar de forma enxuta, mas sem prejudicar o nível de serviço ao cliente. Para isso, busca-se uma rápida e adequada integração das necessidades do mercado na direção dos fornecedores, de modo a balancear e alinhar estrategicamente a demanda com a capacidade operacional ao longo de toda a cadeia de suprimentos. Para a presente pesquisa, utilizou-se levantamento do tipo survey, e o objetivo geral é verificar o panorama atual das práticas de Gestão de Demanda e Previsão de Demanda nas indústrias da Cadeia de Suprimentos Automotiva Brasileira, identificando as principais práticas utilizadas e as principais dificuldades relacionadas à execução dos processos de gestão e previsão de demanda, bem como as consequências causadas pelas variações e incertezas de demanda. Para tanto, com base na revisão da literatura e no método hipotético dedutivo de Popper, foi elaborado um questionário que foi respondido por 37 empresas da cadeia de suprimento automotiva dos mais diversos setores. Os resultados mostram que as empresas da cadeira de suprimento automotiva fazem uso com predominância de técnicas mais simples como opiniões de executivos e da equipe de vendas e utilização de médias móveis. A falta de disponibilidade de dados, a necessidade de capacitação e treinamento da equipe e a deficiencia no conhecimento dos modelos e ferramentas de previsão de demanda aparecem como as maiores barreiras para elaboração das previsões de demanda. / With the continued growth of global competitiveness, the challenge is to work lean way, but without affecting the level of customer service. As a result, a quick and proper integration of the market requirements towards suppliers should be sought, in order to balance and strategically align the demand with the operational capacity along the entire supply chain. This research use the survey method and the overall objective is to find what the current situation of Demand Management and Demand Forecasting practices in the industries of Brazilian Automotive Supply Chain, identifying the main practices and the difficulties related to the implementation of the management and demand forecasting processes, as well as those caused consequences as a result of variations and demand uncertainties. Therefore, based on the literature review and popper´s hypothetico-deductive method, it has been designed a questionnaire that was answered by 37 companies in the automotive supply chain in various sectors. The results show that companies in the automotive supply chair make use predominantly of the simplest techniques as executive and sales force opinion methods and use of moving averages. The lack of availability of data, the need of professional training and deficiency of knowledge of the models and demand forecasting tools appear as major barriers to development of demand forecasts.
109

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

Luis Antonio de Santa Eulalia 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.
110

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.

Gisele Sanches da Silva 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).

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