985 resultados para Buffer capacity
Resumo:
Railway capacity determination and expansion are very important topics. In prior research, the competition between different entities such as train services and train types, on different network corridors however have been ignored, poorly modelled, or else assumed to be static. In response, a comprehensive set of multi-objective models have been formulated in this article to perform a trade-off analysis. These models determine the total absolute capacity of railway networks as the most equitable solution according to a clearly defined set of competing objectives. The models also perform a sensitivity analysis of capacity with respect to those competing objectives. The models have been extensively tested on a case study and their significant worth is shown. The models were solved using a variety of techniques however an adaptive E constraint method was shown to be most superior. In order to identify only the best solution, a Simulated Annealing meta-heuristic was implemented and tested. However a linearization technique based upon separable programming was also developed and shown to be superior in terms of solution quality but far less in terms of computational time.
Resumo:
This thesis focused upon the development of improved capacity analysis and capacity planning techniques for railways. A number of innovations were made and were tested on a case study of a real national railway. These techniques can reduce the time required to perform decision making activities that planners and managers need to perform. As all railways need to be expanded to meet increasing demands, the presumption that analytical capacity models can be used to identify how best to improve an existing network at least cost, was fully investigated. Track duplication was the mechanism used to expanding a network's capacity, and two variant capacity expansion models were formulated. Another outcome of this thesis is the development and validation of bi objective models for capacity analysis. These models regulate the competition for track access and perform a trade-off analysis. An opportunity to develop more general mulch-objective approaches was identified.
Resumo:
Stations on Bus Rapid Transit (BRT) lines ordinarily control line capacity because they act as bottlenecks. At stations with passing lanes, congestion may occur when buses maneuvering into and out of the platform stopping lane interfere with bus flow, or when a queue of buses forms upstream of the station blocking inflow. We contend that, as bus inflow to the station area approaches capacity, queuing will become excessive in a manner similar to operation of a minor movement on an unsignalized intersection. This analogy was used to treat BRT station operation and to analyze the relationship between station queuing and capacity. We conducted microscopic simulation to study and analyze operating characteristics of the station under near steady state conditions through output variables of capacity, degree of saturation and queuing. In the first of two stages, a mathematical model was developed for all stopping buses potential capacity with bus to bus interference and the model was validated. Secondly, a mathematical model was developed to estimate the relationship between average queue and degree of saturation and calibrated for a specified range of controlled scenarios of mean and coefficient of variation of dwell time.
Resumo:
Railways are an important mode of transportation. They are however large and complex and their construction, management and operation is time consuming and costly. Evidently planning the current and future activities is vital. Part of that planning process is an analysis of capacity. To determine what volume of traffic can be achieved over time, a variety of railway capacity analysis techniques have been created. A generic analytical approach that incorporates more complex train paths however has yet to be provided. This article provides such an approach. This article extends a mathematical model for determining the theoretical capacity of a railway network. The main contribution of this paper is the modelling of more complex train paths whereby each section can be visited many times in the course of a train’s journey. Three variant models are formulated and then demonstrated in a case study. This article’s numerical investigations have successively shown the applicability of the proposed models and how they may be used to gain insights into system performance.
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Despite significant improvements in capacity-distortion performance, a computationally efficient capacity control is still lacking in the recent watermarking schemes. In this paper, we propose an efficient capacity control framework to substantiate the notion of watermarking capacity control to be the process of maintaining “acceptable” distortion and running time, while attaining the required capacity. The necessary analysis and experimental results on the capacity control are reported to address practical aspects of the watermarking capacity problem, in dynamic (size) payload embedding.
Resumo:
QUT has enacted a university-wide Peer Program’s Strategy which aims to improve student success and graduate outcomes. A component of this strategy is a training model providing relevant, quality-assured and timely training for all students who take on leadership roles. The training model is designed to meet the needs of the growing scale and variety of peer programs, and to recognise the multiple roles and programs in which students may be involved during their peer leader journey. The model builds peer leader capacity by offering centralised, beginning and ongoing training modules, delivered by in-house providers, covering topics which prepare students to perform their role safely, inclusively, accountably and skilfully. The model also provides efficiencies by differentiating between ‘core competency' and ‘program-specific’ modules, thus avoiding training duplication across multiple programs, and enabling training to be individually and flexibly formatted to suit the specific and unique needs of each program.
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Resource assignment and scheduling is a difficult task when job processing times are stochastic, and resources are to be used for both known and unknown demand. To operate effectively within such an environment, several novel strategies are investigated. The first focuses upon the creation of a robust schedule, and utilises the concept of strategically placed idle time (i.e. buffering). The second approach introduces the idea of maintaining a number of free resources at each time, and culminates in another form of strategically placed buffering. The attraction of these approaches is that they are easy to grasp conceptually, and mimic what practitioners already do in practice. Our extensive numerical testing has shown that these techniques ensure more prompt job processing, and reduced job cancellations and waiting time. They are effective in the considered setting and could easily be adapted for many real life problems, for instance those in health care. This article has more importantly demonstrated that integrating the two approaches is a better strategy and will provide an effective stochastic scheduling approach.
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This thesis examined the long-term impact of the community arts education project Yonder, a collaboration between Education Queensland and Queensland Performing Arts Centre. The findings from the data reveal that the project was still having impact twelve months after its completion and that in some instances the project served as a 'circuit-breaker', especially for special needs students and struggling students. The intervention of a rich arts project proved to be an opportunity for these students to learn in a different way and to perceive themselves in a new and reinvented light. This confidence was found to transfer into other aspects of their learning.
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BACKGROUND Law is increasingly involved in clinical practice, particularly at the end of life, but undergraduate and postgraduate education in this area remains unsystematic. We hypothesised that attitudes to and knowledge of the law governing withholding/withdrawing treatment from adults without capacity (the WWLST law) would vary and demonstrate deficiencies among medical specialists. AIMS We investigated perspectives, knowledge and training of medical specialists in the three largest (populations and medical workforces) Australian states, concerning the WWLST law. METHODS Following expert legal review, specialist focus groups, pre-testing and piloting in each state, seven specialties involved with end-of-life care were surveyed, with a variety of statistical analyses applied to the responses. RESULTS Respondents supported the need to know and follow the law. There were mixed views about its helpfulness in medical decision-making. Over half the respondents conceded poor knowledge of the law; this was mirrored by critical gaps in knowledge that varied by specialty. There were relatively low but increasing rates of education from the undergraduate to continuing professional development (CPD) stages. Mean knowledge score did not vary significantly according to undergraduate or immediate postgraduate training, but CPD training, particularly if recent, resulted in greater knowledge. Case-based workshops were the preferred CPD instruction method. CONCLUSIONS Teaching of current and evolving law should be strengthened across all stages of medical education. This should improve understanding of the role of law, ameliorate ambivalence towards the law, and contribute to more informed deliberation about end-of-life issues with patients and families.
Resumo:
The benefits of peer leader experiences in building graduate skills and capabilities, is well documented and recognised in the higher education sector (Ender & Kay, 2001; Lindsey, Weiler, Zarich, Haddock, Krafchick, & Zimmerman, 2014; Shook & Keup, J., 2012). While benefits are acknowledged, responsibility for identifying, structuring and recording the learning experiences and learning outcomes is charged to the student. This poster describes a framework ‘The Peer Leader Capacity Building Model’ that purposefully structures the peer-leader’s learning journey providing: timely training, moments of critical reflection and goal setting. The model articulates the fundamental interplay of learning and peer leader service which forms the peer ‘learnership’. The journey begins with the ‘aspiration’ phase where students come to understand their leadership opportunities, progressing through ‘enabling’ and ‘mastering’ phases where students shape their learner-leader experience, and finally, to the ‘contributing graduate’ phase where students emerge as competent graduates able to confidently participate in their communities and workplaces. In shifting from a program centric approach that priorities the needs of the mentees, the Peer Leader Capacity Building Model focuses on the individual as a peer leader encouraging the student to shape their individual ‘learnscape’ through consciously navigating both their curricula and co-curricular learning experiences.
Resumo:
‘Complexity’ is a term that is increasingly prevalent in conversations about building capacity for 21st Century professional engineers. Society is grappling with the urgent and challenging reality of accommodating seven billion people, meeting needs and innovating lifestyle improvements in ways that do not destroy atmospheric, biological and oceanic systems critical to life. Over the last two decades in particular, engineering educators have been active in attempting to build capacity amongst professionals to deliver ‘sustainable development’ in this rapidly changing global context. However curriculum literature clearly points to a lack of significant progress, with efforts best described as ad hoc and highly varied. Given the limited timeframes for action to curb environmental degradation proposed by scientists and intergovernmental agencies, the authors of this paper propose it is imperative that curriculum renewal towards education for sustainable development proceeds rapidly, systemically, and in a transformational manner. Within this context, the paper discusses the need to consider a multiple track approach to building capacity for 21st Century engineering, including priorities and timeframes for undergraduate and postgraduate curriculum renewal. The paper begins with a contextual discussion of the term complexity and how it relates to life in the 21st Century. The authors then present a whole of system approach for planning and implementing rapid curriculum renewal that addresses the critical roles of several generations of engineering professionals over the next three decades. The paper concludes with observations regarding engaging with this approach in the context of emerging accreditation requirements and existing curriculum renewal frameworks.
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This publication emanates from the four-country research project entitled “Strengthening capacity for disability-inclusive education development policy formulation, implementation and monitoring in the South Pacific region” funded by the Australian Development Research Award Scheme (ADRAS) and conducted jointly by the academic staff from the Queensland University of Technology and the University of the South Pacific.
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The need for better and more accurate assessments of testamentary and decision-making capacity grows as Australian society ages and incidences of mentally disabling conditions increase. Capacity is a legal determination, but one on which medical opinion is increasingly being sought. The difficulties inherent within capacity assessments are exacerbated by the ad hoc approaches adopted by legal and medical professionals based on individual knowledge and skill, as well as the numerous assessment paradigms that exist. This can negatively affect the quality of assessments, and results in confusion as to the best way to assess capacity. This article begins by assessing the nature of capacity. The most common general assessment models used in Australia are then discussed, as are the practical challenges associated with capacity assessment. The article concludes by suggesting a way forward to satisfactorily assess legal capacity given the significant ramifications of getting it wrong.
Resumo:
The effects of mentally disabling conditions on legal capacity are escalating, particularly given the ageing Australian demographic. Wills, enduring powers of attorney, and advance health directives are coming to the fore as a means of ensuring that the wishes of people with regard to their property, finances and health care needs are respected should they become legally incapable of making their own decisions. Assessing when a person has lost legal capacity in this context is an ever-increasing concern facing society as a whole but, in particular, the legal and medical professionals conducting the assessments. Empirical and doctrinal research has been undertaken which canvassed legal and medical opinions about the relationship between members of these professions when assessing legal capacity. This research supports the hypothesis that tensions exist when assessing capacity, especially testamentary capacity. One source of tension is the effect of conflicting evidence about the loss of legal capacity given by legal and medical professionals in court, which raises questions such as: which evidence is, and should be, preferred; and who should be responsible? The exploration of these issues will be conducted with reference to the empirical data collected, and a review of the relevant Australian case law.