980 resultados para page model
Resumo:
Airport system is complex. Passenger dynamics within it appear to be complicate as well. Passenger behaviours outside standard processes are regarded more significant in terms of public hazard and service rate issues. In this paper, we devised an individual agent decision model to simulate stochastic passenger behaviour in airport departure terminal. Bayesian networks are implemented into the decision making model to infer the probabilities that passengers choose to use any in-airport facilities. We aim to understand dynamics of the discretionary activities of passengers.
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Papua New Guinea has reformed its colonial established education system and made huge investments with the help of donors to achieve equal access and quality education for all its citizens. Despite this national aspiration and these policy reforms and investments, secondary schools that enrol grade 9 students who are relatively equal in education ability show huge disparities in their grade 10 academic performances. This study examined perceptions of students, teachers and principals regarding factors affecting the disparity in academic performance in the context of a developing country. The central question for the study is: What are the perceptions of students and teachers of the factors that affect disparities in secondary schools' academic performance? This qualitative case study involved two high and three low academic performing secondary schools in Western Highlands Province of Papua New Guinea. Primary data were collected through focus groups and semi-structured interviews involving 112 participants. Students and teachers are key participants in this study, as it intends to find out the realities of schools, yet they are an under-researched group. A postcolonial and sense of community conceptual framework was developed for the analysis of the participants. perceptions. In addition, scholarship on school effectiveness and equity in education informed the interpretation of the findings. Three themes were evident in participants. views. First, participants expressed their view that differences in academic performance were related to the adequacy and equitability of resources. The inequities in resource inputs led some of them to coin the metaphor of .back page and front page. schools. Second, many expressed the view that deficiencies in implementing bilingual education, given the difficulty of catering for 800 vernacular languages, contribute to poor English proficiency and subsequent poor academic performance. Finally, participants believed that, in order to have a positive school culture, it is necessary for educators to recognise and respect contemporary students. identities, communal/tribal membership and needs. This study has implications for national education policy on resource allocation to address equality and equity, bilingual education and teacher education. Moreover, as the study found that high academic performance in this context is also influenced by intra-school social relationships, these relationships need to be nurtured. When appropriately nurtured, they become an important factor in sustaining quality education for all secondary school students. This thesis has laid the foundations for further research and invites further investigations into policy and implementation of school reforms aimed at improving academic achievement.
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Design Science Research (DSR) has emerged as an important approach in Information Systems (IS) research. However, DSR is still in its genesis and has yet to achieve consensus on even the fundamentals, such as what methodology / approach to use for DSR. While there has been much effort to establish DSR methodologies, a complete, holistic and validated approach for the conduct of DSR to guide IS researcher (especially novice researchers) is yet to be established. Alturki et al. (2011) present a DSR ‘Roadmap’, making the claim that it is a complete and comprehensive guide for conducting DSR. This paper aims to further assess this Roadmap, by positioning it against the ‘Idealized Model for Theory Development’ (IM4TD) (Fischer & Gregor 2011). The IM4TD highlights the role of discovery and justification and forms of reasoning to progress in theory development. Fischer and Gregor (2011) have applied IM4TD’s hypothetico-deductive method to analyze DSR methodologies, which is adopted in this study to deductively validate the Alturki et al. (2011) Roadmap. The results suggest that the Roadmap adheres to the IM4TD, is reasonably complete, overcomes most shortcomings identified in other DSR methodologies and also highlights valuable refinements that should be considered within the IM4TD.
Resumo:
Business process management (BPM) is becoming the dominant management paradigm. Business process modelling is central to BPM, and the resultant business process model the core artefact guiding subsequent process change. Thus, model quality is at the centre, mediating between the modelling effort and related growing investment in ultimate process improvements. Nonetheless, though research interest in the properties that differentiate high quality process models is longstanding, there have been no past reports of a valid, operationalised, holistic measure of business process model quality. In attention to this gap, this paper reports validation of a Business Process Model Quality measurement model, conceptualised as a single-order, formative index. Such a measurement model has value as the dependent variable in rigorously researching the drivers of model quality; as antecedent of ultimate process improvements; and potentially as an economical comparator and diagnostic for practice.
Resumo:
Peeling is an essential phase of post harvesting and processing industry; however undesirable processing losses are unavoidable and always have been the main concern of food processing sector. There are three methods of peeling fruits and vegetables including mechanical, chemical and thermal, depending on the class and type of fruit. By comparison, the mechanical methods are the most preferred; mechanical peeling methods do not create any harmful effects on the tissue and they keep edible portions of produce fresh. The main disadvantage of mechanical peeling is the rate of material loss and deformations. Obviously reducing material losses and increasing the quality of the process has a direct effect on the whole efficiency of food processing industry, this needs more study on technological aspects of these operations. In order to enhance the effectiveness of food industrial practices it is essential to have a clear understanding of material properties and behaviour of tissues under industrial processes. This paper presents the scheme of research that seeks to examine tissue damage of tough skinned vegetables under mechanical peeling process by developing a novel FE model of the process using explicit dynamic finite element analysis approach. A computer model of mechanical peeling process will be developed in this study to stimulate the energy consumption and stress strain interactions of cutter and tissue. The available Finite Element softwares and methods will be applied to establish the model. Improving the knowledge of interactions and involves variables in food operation particularly in peeling process is the main objectives of the proposed study. Understanding of these interrelationships will help researchers and designer of food processing equipments to develop new and more efficient technologies. Presented work intends to review available literature and previous works has been done in this area of research and identify current gap in modelling and simulation of food processes.
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We derive a semianalytical model to describe the interaction of a single photon emitter and a collection of arbitrarily shaped metal nanoparticles. The theory treats the metal nanoparticles classically within the electrostatic eigenmode method, wherein the surface plasmon resonances of collections of nanoparticles are represented by the hybridization of the plasmon modes of the noninteracting particles. The single photon emitter is represented by a quantum mechanical two-level system that exhibits line broadening due to a finite spontaneous decay rate. Plasmon-emitter coupling is described by solving the resulting Bloch equations. We illustrate the theory by studying model systems consisting of a single emitter coupled to one, two, and three nanoparticles, and we also compare the predictions of our model to published experimental data. ©2012 American Physical Society.
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Traffic safety studies demand more than what current micro-simulation models can provide as they presume that all drivers exhibit safe behaviors. All the microscopic traffic simulation models include a car following model. This paper highlights the limitations of the Gipps car following model ability to emulate driver behavior for safety study purposes. A safety adapted car following model based on the Gipps car following model is proposed to simulate unsafe vehicle movements, with safety indicators below critical thresholds. The modifications are based on the observations of driver behavior in real data and also psychophysical notions. NGSIM vehicle trajectory data is used to evaluate the new model and short following headways and Time To Collision are employed to assess critical safety events within traffic flow. Risky events are extracted from available NGSIM data to evaluate the modified model against them. The results from simulation tests illustrate that the proposed model can predict the safety metrics better than the generic Gipps model. The outcome of this paper can potentially facilitate assessing and predicting traffic safety using microscopic simulation.
Resumo:
The research aimed to identify positive behavioural changes that people may make as a result of negotiating the aftermath of a traumatic experience, thereby extending the current cognitive model of posttraumatic growth (PTG). It was hypothesised that significant others would corroborate survivor’s cognitive and behavioural reports of PTG. The sample comprised 176 participants; 88 trauma survivors and 88 significant others. University students accounted for 64% of the sample and 36% were from the broader community. Approximately one third were male. All participants completed the Posttraumatic Growth Inventory [PTGI] and open ended questions regarding behavioural changes. PTGI scores in the survivor sample were corroborated by the significant others with only the Appreciation of Life factor of the PTGI differing between the two groups (e.g., total PTGI scores between groups explained 33.64% of variance). Nearly all of the survivors also reported positive changes in their behaviour and these changes were also corroborated by the significant others. Results provide validation of the posttraumatic growth construct and the PTGI as an instrument of measurement. Findings may also influence therapeutic practice for example, the potential usefulness of corroborating others.
Resumo:
A strongly progressive surveying and mapping industry depends on a shared understanding of the industry as it exists, some shared vision or imagination of what the industry might become, and some shared action plan capable of bringing about a realisation of that vision. The emphasis on sharing implies a need for consensus reached through widespread discussion and mutual understanding. Unless this occurs, concerted action is unlikely. A more likely outcome is that industry representatives will negate each other's efforts in their separate bids for progress. The process of bringing about consensual viewpoints is essentially one of establishing an industry identity. Establishing the industry's identity and purpose is a prerequisite for rational development of the industry's education and training, its promotion and marketing, and operational research that can deal .with industry potential and efficiency. This paper interprets evolutionary developments occurring within Queensland's surveying and mapping industry within a framework that sets out logical requirements for a viable industry.
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Iran as a developing country faces many considerable shortages of both physical learning environment and inefficient budget to resolve this shortage. Today, Iran needs a $28 billion budget to add 23,000 schools to the existing 120,000 schools to be able to omit two shifts schools [1], [2]. Moreover, the standard learning space is 6-8 square meter per student, while this rate for big cities in Iran is about one square meter per student [1]. This decrease the time students spend in schools. In addition, the education approach in k-12 and higher education is still teacher-centered based and needs to be contemporized with educational, cultural, and technological changes.
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Three dimensional geological modelling techniques have been applied since 1996 with an aim to characterise the lithological and chronological units of New Zealand’s many diverse aquifers. Models of property-scattered data have also been applied to assess physical properties of aquifers and the distribution of groundwater chemistry, including groundwater age, to inform an understanding of groundwater systems. These models, fundamental to understanding groundwater recharge, flow and discharge have found many uses as outlined in this paper.
Resumo:
Breast cancer in its advanced stage has a high predilection to the skeleton. Currently, treatment options of breast cancer-related bone metastasis are restricted to only palliative therapeutic modalities. This is due to the fact that mechanisms regarding the breast cancer celI-bone colonisation as well as the interactions of breast cancer cells with the bone microenvironment are not fully understood, yet. This might be explained through a lack of appropriate in vitro and in vivo models that are currently addressing the above mentioned issue. Hence the hypothesis that the translation of a bone tissue engineering platform could lead to improved and more physiological in vitro and in vivo model systems in order to investigate breast cancer related bone colonisation was embraced in this PhD thesis. Therefore the first objective was to develop an in vitro model system that mimics human mineralised bone matrix to the highest possible extent to examine the specific biological question, how the human bone matrix influences breast cancer cell behaviour. Thus, primary human osteoblasts were isolated from human bone and cultured under osteogenic conditions. Upon ammonium hydroxide treatment, a cell-free intact mineralised human bone matrix was left behind. Analyses revealed a similar protein and mineral composition of the decellularised osteoblast matrix to human bone. Seeding of a panel of breast cancer cells onto the bone mimicking matrix as well as reference substrates like standard tissue culture plastic and collagen coated tissue culture plastic revealed substrate specific differences of cellular behaviour. Analyses of attachment, alignment, migration, proliferation, invasion, as well as downstream signalling pathways showed that these cellular properties were influenced through the osteoblast matrix. The second objective of this PhD project was the development of a human ectopic bone model in NOD/SCID mice using medical grade polycaprolactone tricalcium phosphate (mPCL-TCP) scaffold. Human osteoblasts and mesenchymal stem cells were seeded onto an mPCL-TCP scaffold, fabricated using a fused deposition modelling technique. After subcutaneous implantation in conjunction with the bone morphogenetic protein 7, limited bone formation was observed due to the mechanical properties of the applied scaffold and restricted integration into the soft tissue of flank of NOD/SCID mice. Thus, a different scaffold fabrication technique was chosen using the same polymer. Electrospun tubular scaffolds were seeded with human osteoblasts, as they showed previously the highest amount of bone formation and implanted into the flanks of NOD/SCID mice. Ectopic bone formation with sufficient vascularisation could be observed. After implantation of breast cancer cells using a polyethylene glycol hydrogel in close proximity to the newly formed bone, macroscopic communication between the newly formed bone and the tumour could be observed. Taken together, this PhD project showed that bone tissue engineering platforms could be used to develop an in vitro and in vivo model system to study cancer cell colonisation in the bone microenvironment.
Resumo:
Use of patient-specific computer models as a pre-operative planning tool permits predictions of the likely deformity correction and allows a more detailed investigation of the biomechanical influence of different surgical procedures on the scoliotic spinal anatomy. In this paper, patient-specific computer models are used of adolescent idiopathic scoliosis patients who underwent a single rod anterior procedure at the Mater Children’s Hospital in Brisbane, to predict deformity correction and to investigate the change in biomechanics of the scoliotic spine due to surgical compressive forces applied during implant placement.
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Synthetic scaffolds combined with growth factors have the potential to replace allograft or autograft as a graft material for spinal interbody fusion. Such tissue engineering approaches may be useful in Adolescent Idiopathic Scoliosis (AIS) surgery, however there are no studies to date examining the use of such biodegradable implants in combination with biologics in a thoracic spine model. This in vivo study examines the use of biodegradable polycaprolactone (PCL) based scaffolds with rhBMP-2 as a bone graft substitute in a sheep thoracic fusion model, where an anterior approach is used to simulate minimally invasive surgical deformity correction in the setting of AIS.