286 research outputs found

    Aircraft and high speed train substitution: the case for airline and railway integration.

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    Aircraft and High Speed Train (HST) operations usually result in competition between the airlines and the railways, leading the former to resist mode substitution and thus limiting its potential benefits. This research proposes a different model of substitution, one in which the airlines replace the aircraft by HST on some routes but continue to provide the services through code share agreements with the railways which operate the HST. In addition, the model assumes that the HST service is provided from the airport and is fully integrated with the rest of the airline's route network, leading to airline and railway integration. Under this model, the research has shown that airlines benefit from integration (as well as the railways and the airports) and thus have an incentive to adopt mode substitution. Furthermore, passengersa nd society also benefit, the former from travel time savings and the latter from reduced environmental pollution, making integration a win-win option. Adopting an empirical approach, the benefits from airline and railway integration are evaluated using Cost Benefit Analysis (CBA) and Multi Criteria Analysis (MCA) frameworks, and using the London Heathrow airport to Paris route as a case study. The analysis showed that HST and rail services at airports provide an alternative to investment in increasing runway capacity and that this secures additional benefits at a comparable cost. Specifically for Heathrow, airline and railway integration was found to be the only option to resolve the Government's three main policy goals for the airport, namely preserving its international competitive position as a transfer/hub airport in order to secure its contribution to the national economy; increasing services from the regions, and thus accessibility from the regions to London and the rest of the world; and to curb its impact on the environment. Furthermore, integration between modes, a key policy target in the UK and the EU, is promoted. The above holds for other airports as well. Following from the above, the research recommends adopting airline and railway integration as the model for aircraft and HST substitution and calls for the definition of air transport infrastructure to be changed and to include HST lines and stations. On the methodological aspects, the use of a detailed empirical analysis, which includes the use of comprehensive evaluation practices, is recommended as the basis for forming transport policies. The analysis has shown that it is necessary to rely on the CBA results, but the recommendation is to support these results with MCA to provide evidence for its robustness. In addition, it was found that the common units of passenger-km are not always appropriate and that it is important to present the results in different units

    The macro-economic effects of health co-benefits associated with climate change mitigation strategies

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    The UK government has specific targets for greenhouse gas (GHG) emission reduction to lower the risk of dangerous climate change. Strategies to reduce GHG emissions are sometimes perceived as expensive and difficult to implement but previous work has demonstrated significant potential health co-benefits from ‘Active Travel and low carbon driving’, ‘Housing Insulation/Ventilation’, and ‘Healthy Diet’ scenarios which may be attractive to policymakers. Here a Computable General Equilibrium model is used to assess the financial effects of such health co-benefits on the wider economy including changes in labour force, social security payments and healthcare costs averted. Results suggest that for all scenarios the financial impacts of the health co-benefits will be positive and increased active travel in particular is likely to make a substantial contribution, largely due to health care costs averted. Strategies to reduce GHG emissions and improve health are likely to result in substantial and increasing positive contributions to the economy which may offset some potential economic costs and thereby be seen more favourably in times of economic austerity

    geo climatic applicability of direct evaporative cooling in italy

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    This chapter focuses on the climatic applicability of passive direct (downdraught) evaporative cooling (PDEC) techniques in the provincial capital cities of Italy. First, a PDEC potentiality map was produced using a previously developed method based on three variables: wet bulb depression, summer comfort air temperature threshold (25 °C) and cooling degree hours (CDHs). Second, an applicability map was produced by comparing the PDEC potentiality map to the local cooling energy demand. Third, a new method is presented including a calculation of the residual local cooling energy demand, i.e. residual CDH, related to air treatment by direct evaporative cooling. These residual CDH values were calculated considering different step-wise increasing outlet temperatures (WBT; WBT + 1 °C; …; WBT + 5 °C) as a function of the covered amount of wet bulb depression. Finally, three cities chosen as being representative of their respective Italian climatic macro-zones were selected in order to assess in greater detail the yearly variation of CDH aimed at supporting specific design strategies for ventilative passive cooling solutions

    A multi-modal network approach to model public transport accessibility impacts of bicycle-train integration policies

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    In the Netherlands, the bicycle plays an important in station access and, to a lesser extent, in station egress. There is however fairly little knowledge in the potential effects of bicycle-train integration policies. The aim of this paper is to examine the impacts of bicycle-train integration policies on train ridership and job accessibility for public transport users.MethodsWe extended the Dutch National Transport Model (NVM) by implementing a detailed bicycle network linked to the public transport network, access/egress mode combinations and station specific access and egress penalties by mode and station type derived from a stated choice survey. Furthermore, the effects of several bicycletrain integration policy scenarios were examined for a case study for Randstad South, in the Netherlands, comprising a dense train network with 54 train stations.ConclusionsOur analysis shows that improving the quality of bicycle routes and parking can substantially increase train ridership and potential job accessibility for train users. Large and medium stations are more sensitive to improvements in bicycle-train integration policies, while small stations are more sensitive to improvements in the train level of service

    The effect of temperature, gradient and load carriage on oxygen consumption, posture and gait characteristics

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    Purpose The purpose of this experiment was to evaluate the effect of load carriage in a range of temperatures to establish the interaction between cold exposure, the magnitude of change from unloaded to loaded walking and gradient. Methods Eleven participants (19-27 years) provided written informed consent before performing six randomly ordered walking trials in six temperatures (20°C, 10°C, 5°C, 0°C, -5°C and -10°C). Trials involved two unloaded walking bouts before and after loaded walking (18.2 kg) at 4 km.hr⁻¹, on 0% and 10% gradients in 4 minute bouts. Results The change in absolute oxygen consumption (V̇O₂) from the first unloaded bout to loaded walking was similar across all six temperatures. When repeating the second unloaded bout, V̇O₂ at both -5°C and-10°C was greater compared to the first. At -10°C, V̇O₂ was increased from 1.60 ± 0.30 L.min⁻¹ to 1.89 ± 0.51 L.min⁻¹. Regardless of temperature, gradient had a greater effect on V̇O₂ and heart rate (HR) than backpack load. HR was unaffected by temperature. Stride length (SL) decreased with decreasing temperature but trunk forward lean was greater during cold exposure. Conclusion Decreased ambient temperature did not influence the magnitude of change in V̇O₂ from unloaded to loaded walking. However, in cold temperatures, V̇O₂ was significantly higher than in warm conditions. The increased V̇O₂ in colder temperatures at the same exercise intensity is predicted to ultimately lead to earlier onset of fatigue and cessation of exercise. These results highlight the need to consider both appropriate clothing and fitness during cold exposure

    Estudo de conforto em espaços abertos em região de clima temperado: o caso de Glasgow, Reino Unido

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    O estudo da sensação de conforto térmico em espaços abertos deve ser entendido como primordial para o planejamento climaticamente adequado de áreas urbanas. Através do aumento da atratividade das àreas abertas e do incentivo às atividades ao ar livre, o planejamento urbano norteado do pelas preferências térmicas da população torna-se um agente facilitador do uso desses espaços. O presente trabalho analisa a sensação térmica de moradores de Glasgow, Reino Unido, localizada em região temperada, comparando respostas obtidas por meio de entrevistas estruturadas a índices utilizados pela meteorologia (Wind Chill e THSW) e em estudos de conforto (PET e PMV). Os dados foram coletados em 19 campanhas de monitoramento, no período do inverno ao verão de 2011. Para a coleta de dados, foi utilizada uma estação Davis Vantage Pro2, contendo sensores de temperatura e umidade relativa, anemômetro e piranômetro. Foi confeccionado um termômetro de globo, utilizado para obtenção da temperatura radiante média (TRM), equipado com um data logger (Tinytag-TGP-4500). Os resultados indicam que os índices THSW e PET foram os que mais se aproximaram da resposta térmica dos entrevistados, podendo ser aplicados no entendimento das condições do clima na cidade e entorno de Glasgow

    Is radical innovation in architecture crucial to sustainability? Lessons from three Scottish contemporary buildings

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    Radical innovation is largely recognised as a medium for advancement, a source of growth for economies, and a trigger for progress in different economic sectors. Often, this type of innovation is identified with technological advancements, disruptive phenomena and the creation of new systems and dynamics. Yet, within the context of a changing world, in which principles of economic, environmental and social sustainability are largely adopted as common objectives, a reflection on the type of progress and the need for radical innovation is necessary with the aim of informing on their impacts and effectiveness. This work presents an analysis of a number of contemporary Scottish architectural designs, developed under the aegis of sustainability principles, and explores the types of sustainable innovations introduced and the results achieved by analyzing the type of design change that triggered specific sustainable results, demonstrating alternative innovation strategies, other than the radical one. This analysis provides a basis for discussion on the need for radical innovation in the context of sustainable architecture and explores the role of other types of innovation against the results achieved. This discussion could contribute to a better understanding of the current state of practice in architectural design, as well as in policy making in regard to the design and management of the future built environment

    Potencial de economia de energia elétrica através do uso da luz natural e da ventilação híbrida em edifícios comerciais em Florianópolis

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    O objetivo deste estudo é estimar o potencial de economia de energia elétrica com o uso da luz natural integrada ao sistema de iluminação artificial e a utilização da ventilação híbrida em edifícios comerciais localizados em Florianópolis, SC. O trabalho foi baseado em simulações computacionais nos programas EnergyPlus e Daysim. Foram simulados modelos de ambientes de edificações comerciais, com três geometrias, três dimensões de sala por geometria, dez áreas de janela por modelo e quatro orientações. Os modelos foram examinados por meio de quatro estudos de caso. No Caso 1 (referência), a edificação opera com sistemas de iluminação e de condicionamento artificiais; no Caso 2, ocorre a integração da iluminação natural com a artificial, com condicionamento artificial; já no Caso 3, utilizam-se a ventilação híbrida e a iluminação artificial; no Caso 4, adotam-se a iluminação natural integrada com a artificial e a ventilação híbrida. Os consumos de eletricidade do Caso 1 foram comparados com os demais casos. Assim, foi estimado o potencial de economia de energia elétrica gerado pelo uso da luz natural e ventilação híbrida. Conclui-se que a utilização da iluminação natural e da ventilação híbrida em edificações comerciais localizadas em Florianópolis apresenta potencial de economia de energia elétrica de até 64,9% e que essas estratégias podem ser utilizadas para aumentar a eficiência energética desse tipo de edificação

    CFD como ferramenta para simular ventilação natural interna por ação dos ventos: estudos de caso em tipologias verticais do "Programa Minha Casa, Minha Vida"

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    Resumo A ventilação natural é uma estratégia projetual passiva que deve ser usada sempre que possível em países de clima quente como o Brasil. Entre os vários métodos para predizer o comportamento da ventilação natural está o uso da dinâmica de fluidos computacional. O objetivo deste artigo é analisar a ventilação natural por ação dos ventos no interior de edifícios usando o método de simulação por CFD. A pesquisa toma como estudos de caso três edifícios multifamiliares do Programa Minha Casa, Minha Vida. Analisou-se o desempenho da ventilação para três ângulos de incidência do vento (0º, 90º e 135º). São apresentados resultados quantitativos (velocidade média do vento em cada ambiente interno) e qualitativos (imagens do fluxo de ar externo e interno). Os resultados indicaram melhor desempenho de ventilação na tipologia 1, com planta do tipo "H", na qual a abertura localizada na grande reentrância representou papel determinante. Na tipologia 2, com volumetria próxima ao quadrado, a solução de ventilar banheiro e cozinha através da abertura da área de serviço mostrou-se ineficiente. O pior desempenho foi verificado na tipologia 3, caracterizada por maiores fachadas monolíticas (sem reentrâncias)
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