911 resultados para train delays


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High Speed Rail (HSR) is rapidly gaining popularity worldwide as a safe and efficient transport option for long-distance travel. Designed to win market shares from air transport, HSR systems optimise their productivity between increasing speeds and station spacing to offer high quality service and gain ridership. Recent studies have investigated the effects that the deployment of HSR infrastructure has on spatial distribution and the economic development of cities and regions. Findings appear mostly positive at higher geographical scales, where HSR links connect major urban centres several hundred kilometres apart and already well positioned within a national or international context. Also, at the urban level, studies have shown regeneration and concentration effects around HSR station areas with positive returns on city’s image and economy. However, doubts persist on the effects of HSR at an intermediate scale, where the accessibility trade off on station spacing limits access to many small and medium agglomerations. Thereby, their ability to participate in the development opportunities facilitated by HSR infrastructure is significantly reduced. The locational advantages deriving from transport improvements appear contrasting especially in regions that tend to have a polycentric structure, where cities may present greater accessibility disparities between those served by HSR and those left behind. This thesis fits in this context where intermediate and regional cities do not directly enjoy the presence of an HSR station while having an existing or planned proximate HSR corridor. With the aim of understanding whether there might be a solution to this apparent incongruity, the research investigates strategies to integrate HSR accessibility at the regional level. While current literature recommends to commit with ancillary investments to the uplift of station areas and the renewal of feeder systems, I hypothesised the interoperability between the HSR and the conventional networks to explore the possibilities offered by mixed traffic and infrastructure sharing. Thus, I developed a methodology to quantify the exchange of benefits deriving from this synergistic interaction. In this way, it was possible to understand which level of service quality offered by alternative transit strategies best facilitates the distribution of accessibility benefits for areas far from actual HSR stations. Therefore, strategies were selected for their type of service capable of regional extensions and urban penetrations, while incorporating a combination of specific advantages (e.g. speed, sub-urbanity, capacity, frequency and automation) in order to emulate HSR quality with increasingly efficient services. The North-eastern Italian macro region was selected as case study to ground the research offering concurrently a peripheral polycentric metropolitan form, the presence of a planned HSR corridor with some portions of HSR infrastructure implementation, and the project to develop a suburban rail service extended regionally. Results show significant distributive potential, in terms of network effects produced in relation with HSR, in increasing proportions for all the strategies considered: a regional metro rail strategy (abbreviated RMR), a regional high speed rail strategy (abbreviated RHSR), a regional light rail transit (abbreviated LRT) strategy, and a non-stopping continuous railway system (abbreviated CRS) strategy. The provision of additional tools to value HSR infrastructure against its accessibility benefits and their regional distribution through alternative strategies beyond the actual HSR stations, would have great implications, both politically and technically, in moving towards new dimensions of HSR evaluation and development.

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Cities accumulate and distribute vast sets of digital information. Many decision-making and planning processes in councils, local governments and organisations are based on both real-time and historical data. Until recently, only a small, carefully selected subset of this information has been released to the public – usually for specific purposes (e.g. train timetables, release of planning application through websites to name just a few). This situation is however changing rapidly. Regulatory frameworks, such as the Freedom of Information Legislation in the US, the UK, the European Union and many other countries guarantee public access to data held by the state. One of the results of this legislation and changing attitudes towards open data has been the widespread release of public information as part of recent Government 2.0 initiatives. This includes the creation of public data catalogues such as data.gov.au (U.S.), data.gov.uk (U.K.), data.gov.au (Australia) at federal government levels, and datasf.org (San Francisco) and data.london.gov.uk (London) at municipal levels. The release of this data has opened up the possibility of a wide range of future applications and services which are now the subject of intensified research efforts. Previous research endeavours have explored the creation of specialised tools to aid decision-making by urban citizens, councils and other stakeholders (Calabrese, Kloeckl & Ratti, 2008; Paulos, Honicky & Hooker, 2009). While these initiatives represent an important step towards open data, they too often result in mere collections of data repositories. Proprietary database formats and the lack of an open application programming interface (API) limit the full potential achievable by allowing these data sets to be cross-queried. Our research, presented in this paper, looks beyond the pure release of data. It is concerned with three essential questions: First, how can data from different sources be integrated into a consistent framework and made accessible? Second, how can ordinary citizens be supported in easily composing data from different sources in order to address their specific problems? Third, what are interfaces that make it easy for citizens to interact with data in an urban environment? How can data be accessed and collected?

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The deterioration of air quality is a significant issue in large and growing cities. This work investigates particulate emissions from transport, the largest source of air pollution in cities today. Emitters such as busy roads and diesel trains are investigated, with specific reference to the evolution of particles over time and distance. Diesel trains are investigated as an alternative to road traffic in investigating evolutionary processes. Higher emissions and solitary sources mean that the emitted plume can be observed over time in a single location. These results represent the first investigation of the evolution of fine and ultrafine aerosol particles from this type of source. Aerosols near a busy road are investigated, with the result that a dependence of total number concentration on distance from the road is shown to be related to the fragmentation of nanoparticle clusters. Local meteorological conditions are also monitored and humidity is shown to vary with distance from the road in a nonmonotonic way. Particles from a busy road were also examined using a scanning electron microscope, with the intention of understanding the make up of the emitted aerosol plume. It was determined that due to significant surface behaviour post-deposition, this method of analysis could not directly classify airborne pollutants. Some interesting results were obtained however, particularly in terms of composite particles and the analysis of deposited patterns. This thesis introduces new work in terms of the analysis of diesel train particulate emissions, as well as adding further evidence towards the fragmentation process of aerosol evolution in both background concentrations and emitted aerosol plumes.

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This latest briefing by Professor Reece Walters in the What is crime? series, draws attention to an area of harm that is often absent from criminological debate. He highlights the human costs of air pollution and failed attempts to adequately regulate and control such harm. Arguing for a cross disciplinary ‘eco-crime’ narrative, the author calls for greater understanding of the far-reaching consequences of air pollution which could set in train changes which may lead to a ‘more robust and meaningful system of justice’. Describing current arrangements in place to control and regulate air pollution, Walters draws attention to the lack of neutrality in current arrangements and the bias ‘towards the economic imperatives of free trade over and above the centrality of environmental protection’. While attention is often given to direct and individualised instances of ‘crime’, the serious consequences of air pollution are frequently neglected. The negative effects of pollution on health and well-being are often borne by people already experiencing a range of other disadvantages. In a global and national context, it is often the poor who are affected most. Ultimately, political and economic imperatives have historically helped to shape legal and regulatory regimes. Whether this is an inherent flaw in current systems or something that can be overcome in favour of dealing with more wide-ranging harms is an area that requires further discussion and debate.

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A Multimodal Seaport Container Terminal (MSCT) is a complex system which requires careful planning and control in order to operate efficiently. It consists of a number of subsystems that require optimisation of the operations within them, as well as synchronisation of machines and containers between the various subsystems. Inefficiency in the terminal can delay ships from their scheduled timetables, as well as cause delays in delivering containers to their inland destinations, both of which can be very costly to their operators. The purpose of this PhD thesis is to use Operations Research methodologies to optimise and synchronise these subsystems as an integrated application. An initial model is developed for the overall MSCT; however, due to a large number of assumptions that had to be made, as well as other issues, it is found to be too inaccurate and infeasible for practical use. Instead, a method of developing models for each subsystem is proposed that then be integrated with each other. Mathematical models are developed for the Storage Area System (SAS) and Intra-terminal Transportation System (ITTS). The SAS deals with the movement and assignment of containers to stacks within the storage area, both when they arrive and when they are rehandled to retrieve containers below them. The ITTS deals with scheduling the movement of containers and machines between the storage areas and other sections of the terminal, such as the berth and road/rail terminals. Various constructive heuristics are explored and compared for these models to produce good initial solutions for large-sized problems, which are otherwise impractical to compute by exact methods. These initial solutions are further improved through the use of an innovative hyper-heuristic algorithm that integrates the SAS and ITTS solutions together and optimises them through meta-heuristic techniques. The method by which the two models can interact with each other as an integrated system will be discussed, as well as how this method can be extended to the other subsystems of the MSCT.

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The National Cultural Policy Discussion Paper—drafted to assist the Australian Government in developing the first national Cultural Policy since Creative Nation nearly two decades ago—envisages a future in which arts, cultural and creative activities directly support the development of an inclusive, innovative and productive Australia. "The policy," it says, "will be based on an understanding that a creative nation produces a more inclusive society and a more expressive and confident citizenry by encouraging our ability to express, describe and share our diverse experiences—with each other and with the world" (Australian Government 3). Even a cursory reading of this Discussion Paper makes it clear that the question of impact—in aesthetic, cultural and economic terms—is central to the Government's agenda in developing a new Cultural Policy. Hand-in-hand with the notion of impact comes the process of measurement of progress. The Discussion Paper notes that progress "must be measurable, and the Government will invest in ways to assess the impact that the National Cultural Policy has on society and the economy" (11). If progress must be measurable, this raises questions about what arts, cultural and creative workers do, whether it is worth it, and whether they could be doing it better. In effect, the Discussion Paper pushes artsworkers ever closer to a climate in which they have to be skilled not just at making work, but at making the impact of this work clear to stakeholders. The Government in its plans for Australia's cultural future, is clearly most supportive of artsworkers who can do this, and the scholars, educators and employers who can best train the artsworkers of the future to do this.

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The National Road Safety Strategy 2011-2020 outlines plans to reduce the burden of road trauma via improvements and interventions relating to safe roads, safe speeds, safe vehicles, and safe people. It also highlights that a key aspect in achieving these goals is the availability of comprehensive data on the issue. The use of data is essential so that more in-depth epidemiologic studies of risk can be conducted as well as to allow effective evaluation of road safety interventions and programs. Before utilising data to evaluate the efficacy of prevention programs it is important for a systematic evaluation of the quality of underlying data sources to be undertaken to ensure any trends which are identified reflect true estimates rather than spurious data effects. However, there has been little scientific work specifically focused on establishing core data quality characteristics pertinent to the road safety field and limited work undertaken to develop methods for evaluating data sources according to these core characteristics. There are a variety of data sources in which traffic-related incidents and resulting injuries are recorded, which are collected for a variety of defined purposes. These include police reports, transport safety databases, emergency department data, hospital morbidity data and mortality data to name a few. However, as these data are collected for specific purposes, each of these data sources suffers from some limitations when seeking to gain a complete picture of the problem. Limitations of current data sources include: delays in data being available, lack of accurate and/or specific location information, and an underreporting of crashes involving particular road user groups such as cyclists. This paper proposes core data quality characteristics that could be used to systematically assess road crash data sources to provide a standardised approach for evaluating data quality in the road safety field. The potential for data linkage to qualitatively and quantitatively improve the quality and comprehensiveness of road crash data is also discussed.

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An enhanced mill extraction model has been developed to calculate mill performance parameters and to predict the extraction performance of a milling unit. The model takes into account the fibre suspended in juice streams and calculates filling ratio, reabsorption factor, imbibition coefficient, and separation efficiency using more complete definitions than those used in previous extraction models. A mass balance model is used to determine the fibre, brix and moisture mass flows between milling units so that a complete milling train, including the return stream from the juice screen, is modelled. Model solutions are presented to determine the effect of different levels of fibre in juice and efficiency of fibre separation in the juice screen on brix extraction. The model provides more accurate results than earlier models leading to better understanding and improvement of the milling process.

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The scheduling of locomotive movements on cane railways has proven to be a very complex task. Various optimisation methods have been used over the years to try and produce an optimised schedule that eliminates or minimises bin supply delays to harvesters and the factory, while minimising the number of locomotives, locomotive shifts and cane bins, and also the cane age. This paper reports on a new attempt to develop an automatic scheduler using a mathematical model solved using mixed integer programming and constraint programming approaches and blocking parallel job shop scheduling fundamentals. The model solution has been explored using conventional constraint programming search techniques and found to produce a reasonable schedule for small-scale problems with up to nine harvesters. While more effort is required to complete the development of the full model with metaheuristic search techniques, the work completed to date gives confidence that the metaheuristic techniques will provide near optimal solutions in reasonable time.

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In the current era of global economic instability, business and industry have already identified a widening gap between graduate skills and employability. An important element of this is the lack of entrepreneurial skills in graduates. This Teaching Fellowship investigated two sides of a story about entrepreneurial skills and their teaching. Senior players in the innovation commercialisation industry, a high profile entrepreneurial sector, were surveyed to gauge their needs and experiences of graduates they employ. International contexts of entrepreneurship education were investigated to explore how their teaching programs impart the skills of entrepreneurship. Such knowledge is an essential for the design of education programs that can deliver the entrepreneurial skills deemed important by industry for future sustainability. Two programs of entrepreneurship education are being implemented at QUT that draw on the best practice exemplars investigated during this Fellowship. The QUT Innovation Space (QIS) focuses on capturing the innovation and creativity of students, staff and others. The QIS is a physical and virtual meeting and networking space; a connected community enhancing the engagement of participants. The Q_Hatchery is still embryonic; but it is intended to be an innovation community that brings together nascent entrepreneurial businesses to collaborate, train and support each other. There is a niche between concept product and business incubator where an experiential learning environment for otherwise isolated ‘garage-at-home’ businesses could improve success rates. The QIS and the Q_Hatchery serve as living research laboratories to trial the concepts emerging from the skills survey. The survey of skills requirements of the innovation commercialisation industry has produced a large and high quality data set still being explored. Work experience as an employability factor has already emerged as an industry requirement that provides employee maturity. Exploratory factor analysis of the skills topics surveyed has led to a process-based conceptual model for teaching and learning higher-order entrepreneurial skills. Two foundational skills domains (Knowledge, Awareness) are proposed as prerequisites which allow individuals with a suite of early stage entrepreneurial and behavioural skills (Pre-leadership) to further leverage their careers into a leadership role in industry with development of skills around higher order elements of entrepreneurship, management in new business ventures and progressing winning technologies to market. The next stage of the analysis is to test the proposed model through structured equation modelling. Another factor that emerged quickly from the survey analysis broadens the generic concept of team skills currently voiced in Australian policy documents discussing the employability agenda. While there was recognition of the role of sharing, creating and using knowledge in a team-based interdisciplinary context, the adoption and adaptation of behaviours and attitudes of other team members of different disciplinary backgrounds (interprofessionalism) featured as an issue. Most undergraduates are taught and undertake teamwork in silos and, thus, seldom experience a true real-world interdisciplinary environment. Enhancing the entrepreneurial capacity of Australian industry is essential for the economic health of the country and can only be achieved by addressing the lack of entrepreneurial skills in graduates from the higher education system. This Fellowship has attempted to address this deficiency by identifying the skills requirements and providing frameworks for their teaching.

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We present a formalism for the analysis of sensitivity of nuclear magnetic resonance pulse sequences to variations of pulse sequence parameters, such as radiofrequency pulses, gradient pulses or evolution delays. The formalism enables the calculation of compact, analytic expressions for the derivatives of the density matrix and the observed signal with respect to the parameters varied. The analysis is based on two constructs computed in the course of modified density-matrix simulations: the error interrogation operators and error commutators. The approach presented is consequently named the Error Commutator Formalism (ECF). It is used to evaluate the sensitivity of the density matrix to parameter variation based on the simulations carried out for the ideal parameters, obviating the need for finite-difference calculations of signal errors. The ECF analysis therefore carries a computational cost comparable to a single density-matrix or product-operator simulation. Its application is illustrated using a number of examples from basic NMR spectroscopy. We show that the strength of the ECF is its ability to provide analytic insights into the propagation of errors through pulse sequences and the behaviour of signal errors under phase cycling. Furthermore, the approach is algorithmic and easily amenable to implementation in the form of a programming code. It is envisaged that it could be incorporated into standard NMR product-operator simulation packages.

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Monitoring the natural environment is increasingly important as habit degradation and climate change reduce theworld’s biodiversity.We have developed software tools and applications to assist ecologists with the collection and analysis of acoustic data at large spatial and temporal scales.One of our key objectives is automated animal call recognition, and our approach has three novel attributes. First, we work with raw environmental audio, contaminated by noise and artefacts and containing calls that vary greatly in volume depending on the animal’s proximity to the microphone. Second, initial experimentation suggested that no single recognizer could dealwith the enormous variety of calls. Therefore, we developed a toolbox of generic recognizers to extract invariant features for each call type. Third, many species are cryptic and offer little data with which to train a recognizer. Many popular machine learning methods require large volumes of training and validation data and considerable time and expertise to prepare. Consequently we adopt bootstrap techniques that can be initiated with little data and refined subsequently. In this paper, we describe our recognition tools and present results for real ecological problems.

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Aim: As molecular and cytogenetic testing becomes increasingly sophisticated, more individuals are being diagnosed with rare chromosome disorders. Yet despite a burgeoning knowledge about biomedical aspects, little is known about implications for psychosocial development. The scant literature gives a general impression of deficits and adverse developmental outcomes. Method: Developmental data were obtained from two 16 year olds diagnosed with a rare chromosome disorder – a girl with 8p23.1 and a boy with 16q11.2q12.1. Measures of intellectual ability, academic achievement, and other aspects of functioning were administered at multiple time points from early childhood to adolescence. Results: Both adolescents experienced initial delays in motor and language development. Although the girl’s intelligence is assessed as being in the average range, she experiences difficulties with motor planning, spelling and writing. The boy has been diagnosed with a mild intellectual disability and demonstrates mild autistic features. Conclusions: The two case descriptions are in marked contrast to the published literature about these two chromosome anomalies. Both adolescents are developing much more positively than would be expected on the basis of the grim predictions of their paediatricians and the negative reports in the literature. It is concluded that, for most rare chromosome disorders, the range of possible developmental outcomes is currently unknown.

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Unsteady numerical simulation of Rayleigh Benard convection heat transfer from a 2D channel is performed. The oscillatory behavior is attributed to recirculation of ascending and descending flows towards the core of the channel producing organized rolled motions. Variation of the parameters such as Reynolds number, channel outlet flow area and inclination of the channel are considered. Increasing Reynolds number (for a fixed Rayleigh number), delays the generation of vortices. The reduction in the outflow area leads to the later and the less vortex generation. As the time progresses, more vortices are generated, but the reinforced mean velocity does not let the eddies to enter the core of the channel. Therefore, they attach to the wall and reduce the heat transfer area. The inclination of the channel (both positive and negative) induces the generated vortices to get closer to each other and make an enlarged vortex.

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When arranging a place to meet in Brisbane, it has become almost second nature to say, “I’ll meet you outside Hungry Jack’s,” which is located in Queen Street Mall. In Melbourne, the common saying is, “I’ll meet you under the clocks,” which refers to the row of clocks above the main entrance to Flinders Street Railway Station. The saying “I’ll meet you under the clocks” is loaded with memory and history for most Melbournians—from WWII farewells to after school meetings. The clocks, and the station, have become part of the symbolic culture of the city. A feature of these two sites is the diversity of people who arrange to meet there, ranging from business people, tourists, teenagers, lovers, families to local schoolchildren. These two spaces cross boundaries of exclusion and enable people to feel as though they belong the city. While it seems appropriate for people to arrange to meet at a railway station, it is interesting that many people who meet at Flinders Street Station do not travel by train to arrive there: some walk; some take the tram and then walk; others arrive by bus. Similarly, most of the many people who arrange to meet outside Hungry Jack’s in Brisbane do not intend to enter the store...