411 resultados para Simulated environment (Teaching method)
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We present experimental results that demonstrate that the wavelength of the fundamental localised surface plasmon resonance for spherical gold nanoparticles on glass can be predicted using a simple, one line analytical formula derived from the electrostatic eigenmode method. This allows the role of the substrate in lifting mode degeneracies to be determined, and the role of local environment refractive indices on the plasmon resonance to be investigated. The effect of adding silica to the casting solution in minimizing nanopaticle agglomeration is also discussed.
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The dawn of the twenty-first century encouraged a number of scientific and technological organisations to identify what they saw as ‘Grand Challenges and Opportunities’. Issues of environment and health featured very prominently in these quite short lists, as can be seen from a sample of these challenges in Table 1. Indeed, the first two lists of challenges in Table 1 were identified as for the environment and for health, respectively.
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Knowledge has been widely recognised as a determinant of business performance. Business capabilities require an effective share of resource and knowledge. Specifically, knowledge sharing (KS) between different companies and departments can improve manufacturing processes since intangible knowledge plays an enssential role in achieving competitive advantage. This paper presents a mixed method research study into the impact of KS on the effectiveness of new product development (NPD) in achieving desired business performance (BP). Firstly, an empirical study utilising moderated regression analysis was conducted to test whether and to what extent KS has leveraging power on the relationship between NPD and BP constructs and variables. Secondly, this empirically verified hypothesis was validated through explanatory case studies involving two Taiwanese manufacturing companies using a qualitative interaction term pattern matching technique. The study provides evidence that knowledge sharing and management activities are essential for deriving competitive advantage in the manufacturing industry.
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This paper presents a method for investigating ship emissions, the plume capture and analysis system (PCAS), and its application in measuring airborne pollutant emission factors (EFs) and particle size distributions. The current investigation was conducted in situ, aboard two dredgers (Amity: a cutter suction dredger and Brisbane: a hopper suction dredger) but the PCAS is also capable of performing such measurements remotely at a distant point within the plume. EFs were measured relative to the fuel consumption using the fuel combustion derived plume CO2. All plume measurements were corrected by subtracting background concentrations sampled regularly from upwind of the stacks. Each measurement typically took 6 minutes to complete and during one day, 40 to 50 measurements were possible. The relationship between the EFs and plume sample dilution was examined to determine the plume dilution range over which the technique could deliver consistent results when measuring EFs for particle number (PN), NOx, SO2, and PM2.5 within a targeted dilution factor range of 50-1000 suitable for remote sampling. The EFs for NOx, SO2, and PM2.5 were found to be independent of dilution, for dilution factors within that range. The EF measurement for PN was corrected for coagulation losses by applying a time dependant particle loss correction to the particle number concentration data. For the Amity, the EF ranges were PN: 2.2 - 9.6 × 1015 (kg-fuel)-1; NOx: 35-72 g(NO2).(kg-fuel)-1, SO2 0.6 - 1.1 g(SO2).(kg-fuel)-1and PM2.5: 0.7 – 6.1 g(PM2.5).(kg-fuel)-1. For the Brisbane they were PN: 1.0 – 1.5 x 1016 (kg-fuel)-1, NOx: 3.4 – 8.0 g(NO2).(kg-fuel)-1, SO2: 1.3 – 1.7 g(SO2).(kg-fuel)-1 and PM2.5: 1.2 – 5.6 g(PM2.5).(kg-fuel)-1. The results are discussed in terms of the operating conditions of the vessels’ engines. Particle number emission factors as a function of size as well as the count median diameter (CMD), and geometric standard deviation of the size distributions are provided. The size distributions were found to be consistently uni-modal in the range below 500 nm, and this mode was within the accumulation mode range for both vessels. The representative CMDs for the various activities performed by the dredgers ranged from 94-131 nm in the case of the Amity, and 58-80 nm for the Brisbane. A strong inverse relationship between CMD and EF(PN) was observed.
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Aim. To develop and evaluate the implementation of a communication board for paramedics to use with patients as an augmentative or alternative communication tool to address communication needs of patients in the pre-hospital setting. Method. A double-sided A4-size communication board was designed specifically for use in the pre-hospital setting by the Queensland Ambulance Service and Disability and Community Care Services. One side of the board contains expressive messages that could be used by both the patient and paramedic. The other side contains messages to support patients’ understanding and interaction tips for the paramedic. The communication board was made available in every ambulance and patient transport vehicle in the Brisbane Region. Results. A total of 878 paramedics completed a survey that gauged which patient groups they might use the communication board with. The two most common groups were patients from culturally and linguistically diverse backgrounds and children. Staff reported feeling confident in using the board, and 72% of interviewed paramedics agreed that the communication board was useful for aiding communication with patients. Feedback from paramedics suggests that the board is simple to use, reduces patient frustration and improves communication. Conclusion. These results suggest that a communication board can be applied in the pre-hospital setting to support communication success with patients. What is known about the topic? It is imperative that communication between patient and paramedic is clear and effective. Research has shown that communication boards have been effective with people with temporary or permanent communication difficulties. What does this paper add? This is the first paper outlining the development and use of a communication board by paramedics in the pre-hospital setting in Australia. The paper details the design of the communication board for the unique pre-hospital environment. The paper provides some preliminary data on the use of the communication board with certain patient groups and its effectiveness as an alternative communication tool. What are the implications for practitioners? The findings support the use of the tool as a viable option in supporting the communication between paramedics and a range of patients. It is not suggested that this communication board will meet the complete communication needs of any individual in this environment, but it is hoped that the board’s presence within the Queensland Ambulance Service may result in paramedics introducing the board on occasions where communication with a patient is challenging.
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Damage assessment (damage detection, localization and quantification) in structures and appropriate retrofitting will enable the safe and efficient function of the structures. In this context, many Vibration Based Damage Identification Techniques (VBDIT) have emerged with potential for accurate damage assessment. VBDITs have achieved significant research interest in recent years, mainly due to their non-destructive nature and ability to assess inaccessible and invisible damage locations. Damage Index (DI) methods are also vibration based, but they are not based on the structural model. DI methods are fast and inexpensive compared to the model-based methods and have the ability to automate the damage detection process. DI method analyses the change in vibration response of the structure between two states so that the damage can be identified. Extensive research has been carried out to apply the DI method to assess damage in steel structures. Comparatively, there has been very little research interest in the use of DI methods to assess damage in Reinforced Concrete (RC) structures due to the complexity of simulating the predominant damage type, the flexural crack. Flexural cracks in RC beams distribute non- linearly and propagate along all directions. Secondary cracks extend more rapidly along the longitudinal and transverse directions of a RC structure than propagation of existing cracks in the depth direction due to stress distribution caused by the tensile reinforcement. Simplified damage simulation techniques (such as reductions in the modulus or section depth or use of rotational spring elements) that have been extensively used with research on steel structures, cannot be applied to simulate flexural cracks in RC elements. This highlights a big gap in knowledge and as a consequence VBDITs have not been successfully applied to damage assessment in RC structures. This research will address the above gap in knowledge and will develop and apply a modal strain energy based DI method to assess damage in RC flexural members. Firstly, this research evaluated different damage simulation techniques and recommended an appropriate technique to simulate the post cracking behaviour of RC structures. The ABAQUS finite element package was used throughout the study with properly validated material models. The damaged plasticity model was recommended as the method which can correctly simulate the post cracking behaviour of RC structures and was used in the rest of this study. Four different forms of Modal Strain Energy based Damage Indices (MSEDIs) were proposed to improve the damage assessment capability by minimising the numbers and intensities of false alarms. The developed MSEDIs were then used to automate the damage detection process by incorporating programmable algorithms. The developed algorithms have the ability to identify common issues associated with the vibration properties such as mode shifting and phase change. To minimise the effect of noise on the DI calculation process, this research proposed a sequential order of curve fitting technique. Finally, a statistical based damage assessment scheme was proposed to enhance the reliability of the damage assessment results. The proposed techniques were applied to locate damage in RC beams and slabs on girder bridge model to demonstrate their accuracy and efficiency. The outcomes of this research will make a significant contribution to the technical knowledge of VBDIT and will enhance the accuracy of damage assessment in RC structures. The application of the research findings to RC flexural members will enable their safe and efficient performance.
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QUT Teaching and Learning Support Services 'Revisiting University Teaching’program for mid-career academics. 'Innovations in Teaching at QUT' presentations. Presentations were part of a 2 day program that provides opportunities for experienced academic staff with responsibilities for teaching to review their current teaching practices and explore innovations in teaching that will assist them to enhance student learning and develop their own scholarship of teaching. The presenter responded to the following: 1.What is the innovation you have incorporated into your teaching? - give a brief overview/ description/ demonstration of the innovation 2.What challenges/issues prompted you to make changes in your approach? Were they discipline specific? Operational? Opportunistic? 3.What factors did you need to consider in implementing these changes? Which factors enabled success or hindered? 4.What has this innovation achieved so far? How have learners responded? How have the broader teaching team and academic staff from other units in your course responded? 5.How could this innovation be used by other academics in their teaching? What do you see as the possibilities for further expansion of this innovation? (NB. This question could be answered as part of a final sharing of group discussion). Presenter: Shannon Satherley
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Property in an elusive concept. In many respects it has been regarded as a source of authority to use, develop and make decisions about whatever is the subject matter of this right of ownership. This is true whether the holder of this right of ownership is a private entity or a public entity. Increasingly a right of ownership of this kind has been recognised not only as a source of authority but also as a mechanism for restricting or limiting and perhaps even prohibiting existing or proposed activities that impact upon the environment. It is increasingly therefore an instrument of regulation as much as an instrument of authorisation. The protection and conservation of the environment are ultimately a matter of the public interest. This is not to suggest that the individual holders of rights of ownership are not interested in protecting the environment. It is open to them to do so in the exercise of a right of ownership as a source of authorisation. However a right of ownership – whether private or public – has become increasingly the mechanism according to which the environment is protected and conserved through the use of rights of ownership as a means of regulation. This paper addressed these issues from a doctrinal as well as a practical perspective in how the environment is managed.
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Recent fire research into the behaviour of light gauge steel frame (LSF) wall systems has devel-oped fire design rules based on Australian and European cold-formed steel design standards, AS/NZS 4600 and Eurocode 3 Part 1.3. However, these design rules are complex since the LSF wall studs are subjected to non-uniform elevated temperature distributions when the walls are exposed to fire from one side. Therefore this paper proposes an alternative design method for routine predictions of fire resistance rating of LSF walls. In this method, suitable equations are recommended first to predict the idealised stud time-temperature pro-files of eight different LSF wall configurations subject to standard fire conditions based on full scale fire test results. A new set of equations was then proposed to find the critical hot flange (failure) temperature for a giv-en load ratio for the same LSF wall configurations with varying steel grades and thickness. These equations were developed based on detailed finite element analyses that predicted the axial compression capacities and failure times of LSF wall studs subject to non-uniform temperature distributions with varying steel grades and thicknesses. This paper proposes a simple design method in which the two sets of equations developed for time-temperature profiles and critical hot flange temperatures are used to find the failure times of LSF walls. The proposed method was verified by comparing its predictions with the results from full scale fire tests and finite element analyses. This paper presents the details of this study including the finite element models of LSF wall studs, the results from relevant fire tests and finite element analyses, and the proposed equations.
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Cell migration is a behaviour critical to many key biological effects, including wound healing, cancerous cell invasion and morphogenesis, the development of an organism from an embryo. However, given that each of these situations is distinctly different and cells are extremely complicated biological objects, interest lies in more basic experiments which seek to remove conflating factors and present a less complex environment within which cell migration can be experimentally examined. These include in vitro studies like the scratch assay or circle migration assay, and ex vivo studies like the colonisation of the hindgut by neural crest cells. The reduced complexity of these experiments also makes them much more enticing as problems to mathematically model, like done here. The primary goal of the mathematical models used in this thesis is to shed light on which cellular behaviours work to generate the travelling waves of invasion observed in these experiments, and to explore how variations in these behaviours can potentially predict differences in this invasive pattern which are experimentally observed when cell types or chemical environment are changed. Relevant literature has already identified the difficulty of distinguishing between these behaviours when using traditional mathematical biology techniques operating on a macroscopic scale, and so here a sophisticated individual-cell-level model, an extension of the Cellular Potts Model (CPM), is been constructed and used to model a scratch assay experiment. This model includes a novel mechanism for dealing with cell proliferations that allowed for the differing properties of quiescent and proliferative cells to be implemented into their behaviour. This model is considered both for its predictive power and used to make comparisons with the travelling waves which result in more traditional macroscopic simulations. These comparisons demonstrate a surprising amount of agreement between the two modelling frameworks, and suggest further novel modifications to the CPM that would allow it to better model cell migration. Considerations of the model’s behaviour are used to argue that the dominant effect governing cell migration (random motility or signal-driven taxis) likely depends on the sort of invasion demonstrated by cells, as easily seen by microscopic photography. Additionally, a scratch assay simulated on a non-homogeneous domain consisting of a ’fast’ and ’slow’ region is also used to further differentiate between these different potential cell motility behaviours. A heterogeneous domain is a novel situation which has not been considered mathematically in this context, nor has it been constructed experimentally to the best of the candidate’s knowledge. Thus this problem serves as a thought experiment used to test the conclusions arising from the simulations on homogeneous domains, and to suggest what might be observed should this non-homogeneous assay situation be experimentally realised. Non-intuitive cell invasion patterns are predicted for diffusely-invading cells which respond to a cell-consumed signal or nutrient, contrasted with rather expected behaviour in the case of random-motility-driven invasion. The potential experimental observation of these behaviours is demonstrated by the individual-cell-level model used in this thesis, which does agree with the PDE model in predicting these unexpected invasion patterns. In the interest of examining such a case of a non-homogeneous domain experimentally, some brief suggestion is made as to how this could be achieved.
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Proper functioning of Insulated Rail Joints (IRJs) is essential for the safe operation of the railway signalling systems and broken rail identification circuitries. The Conventional IRJ (CIRJ) resembles structural butt joints consisting of two pieces of rails connected together through two joint bars on either side of their web and the assembly is held together through pre-tensioned bolts. As the IRJs should maintain electrical insulation between the two rails, a gap between the rail ends must be retained at all times and all metal contacting surfaces should be electrically isolated from each other using non-conductive material. At the gap, the rail ends lose longitudinal continuity and hence the vertical sections of the rail ends are often severely damaged, especially at the railhead, due to the passage of wheels compared to other continuously welded rail sections. Fundamentally, the reason for the severe damage can be related to the singularities of the wheel-rail contact pressure and the railhead stress. No new generation designs that have emerged in the market to date have focussed on this fundamental; they only have provided attention to either the higher strength materials or the thickness of the sections of various components of the IRJs. In this thesis a novel method of shape optimisation of the railhead is developed to eliminate the pressure and stress singularities through changes to the original sharp corner shaped railhead into an arc profile in the longitudinal direction. The optimal shape of the longitudinal railhead profile has been determined using three nongradient methods in search of accuracy and efficiency: (1) Grid Search Method; (2) Genetic Algorithm Method and (3) Hybrid Genetic Algorithm Method. All these methods have been coupled with a parametric finite element formulation for the evaluation of the objective function for each iteration or generation depending on the search algorithm employed. The optimal shape derived from these optimisation methods is termed as Stress Minimised Railhead (SMRH) in this thesis. This optimal SMRH design has exhibited significantly reduced stress concentration that remains well below the yield strength of the head hardened rail steels and has shifted the stress concentration location away from the critical zone of the railhead end. The reduction in the magnitude and the relocation of the stress concentration in the SMRH design has been validated through a full scale wheel – railhead interaction test rig; Railhead strains under the loaded wheels have been recorded using a non-contact digital image correlation method. Experimental study has confirmed the accuracy of the numerical predications. Although the SMRH shaped IRJs eliminate stress singularities, they can still fail due to joint bar or bolt hole cracking; therefore, another conceptual design, termed as Embedded IRJ (EIRJ) in this thesis, with no joint bars and pre-tensioned bolts has been developed using a multi-objective optimisation formulation based on the coupled genetic algorithm – parametric finite element method. To achieve the required structural stiffness for the safe passage of the loaded wheels, the rails were embedded into the concrete of the post tensioned sleepers; the optimal solutions for the design of the EIRJ is shown to simplify the design through the elimination of the complex interactions and failure modes of the various structural components of the CIRJ. The practical applicability of the optimal shapes SMRH and EIRJ is demonstrated through two illustrative examples, termed as improved designs (IMD1 & IMD2) in this thesis; IMD1 is a combination of the CIRJ and the SMRH designs, whilst IMD2 is a combination of the EIRJ and SMRH designs. These two improved designs have been simulated for two key operating (speed and wagon load) and design (wheel diameter) parameters that affect the wheel-rail contact; the effect of these parameters has been found to be negligible to the performance of the two improved designs and the improved designs are in turn found far superior to the current designs of the CIRJs in terms of stress singularities and deformation under the passage of the loaded wheels. Therefore, these improved designs are expected to provide longer service life in relation to the CIRJs.
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Purpose: Electronic Portal Imaging Devices (EPIDs) are available with most linear accelerators (Amonuk, 2002), the current technology being amorphous silicon flat panel imagers. EPIDs are currently used routinely in patient positioning before radiotherapy treatments. There has been an increasing interest in using EPID technology tor dosimetric verification of radiotherapy treatments (van Elmpt, 2008). A straightforward technique involves the EPID panel being used to measure the fluence exiting the patient during a treatment which is then compared to a prediction of the fluence based on the treatment plan. However, there are a number of significant limitations which exist in this Method: Resulting in a limited proliferation ot this technique in a clinical environment. In this paper, we aim to present a technique of simulating IMRT fields using Monte Carlo to predict the dose in an EPID which can then be compared to the measured dose in the EPID. Materials: Measurements were made using an iView GT flat panel a-SI EPfD mounted on an Elekta Synergy linear accelerator. The images from the EPID were acquired using the XIS software (Heimann Imaging Systems). Monte Carlo simulations were performed using the BEAMnrc and DOSXVZnrc user codes. The IMRT fieids to be delivered were taken from the treatment planning system in DICOMRT format and converted into BEAMnrc and DOSXYZnrc input files using an in-house application (Crowe, 2009). Additionally. all image processing and analysis was performed using another in-house application written using the Interactive Data Language (IDL) (In Visual Information Systems). Comparison between the measured and Monte Carlo EPID images was performed using a gamma analysis (Low, 1998) incorporating dose and distance to agreement criteria. Results: The fluence maps recorded by the EPID were found to provide good agreement between measured and simulated data. Figure 1 shows an example of measured and simulated IMRT dose images and profiles in the x and y directions. "A technique for the quantitative evaluation of dose distributions", Med Phys, 25(5) May 1998 S. Crowe, 1. Kairn, A. Fielding, "The Development of a Monte Carlo system to verify Radiotherapy treatment dose calculations", Radiotherapy & Oncology, Volume 92, Supplement 1, August 2009, Pages S71-S71.
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The purpose of this study was to describe Japanese hospital nurses’ perceptions of the nursing practice environment and examine its association with nurse-reported ability to provide quality nursing care, quality of patient care and ward morale. A cross-sectional survey design was used including 223 nurses working in 12 acute inpatient wards in a large Japanese teaching hospital. Nurses rated their work environment favorably overall using the Japanese version of the Practice Environment Scale of the Nursing Work Index. Subscale scores indicated high perceptions of physician relations and quality of nursing management, but lower scores for staffing and resources. Ward nurse managers generally rated the practice environment more positively than staff nurses except for staffing and resources. Regression analyses found the practice environment was a significant predictor of quality of patient care and ward morale, whereas perceived ability to provide quality nursing care was most strongly associated with years of clinical experience. These findings support interventions to improve the nursing practice environment, particularly staffing and resource adequacy, to enhance quality of care and ward morale in Japan.
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In spite of the activism of professional bodies and researchers, empirical evidence shows that project management still does not deliver the expected benefits and promises. Hence, many have questioned the validity of the hegemonic rationalist paradigm anchored in the Enlightenment and Natural Sciences tradition supporting project management research and practice for the last 60 years and the lack of relevance to practice of the current conceptual base of project management. In order to address these limitations many authors, taking a post-modernist stance in social sciences, build on ‘pre-modern’ philosophies such as the Aristotelian one, specially emphasizing the role of praxis (activity), and phronesis (practical wisdom, prudence). Indeed, ‘Praxis … is the central category of the philosophy which is not merely an interpretation of the world, but is also a guide to its transformation …’ (Vazquez, 1977:. 149). Therefore, praxis offers an important focus for practitioners and researchers in social sciences, one in which theory is integrated with practice at the point of intervention. Simply stated, praxis can serve as a common ground for those interested in basic and applied research by providing knowledge of the reality in which action, informed by theory, takes place. Consequently, I suggest a ‘praxeological’ style of reasoning (praxeology being defined as study or science of human actions and conduct, including praxis, practices and phronesis) and to go beyond the ‘Theory-Practice’ divide. Moreover, I argue that we need to move away from the current dichotomy between the two classes ‘scholars experts-researchers’ and ‘managers/workers-practitioners-participants’. Considering one single class of ‘PraXitioner’, becoming a phronimos, may contribute to create new perspectives and open up new ways of thinking and acting in project situations. Thus, I call for a Perestroika in researching and acting in project management situations. My intent is to suggest a balanced praxeological view of the apparent opposition between social and natural science approaches. I explore, in this chapter, three key questions, covering the ontological, epistemological and praxeological dimensions of project management in action. 1. Are the research approaches being currently used appropriate for generating contributions that matter to both theory and practice with regards to what a ‘project’ is or to what we do when we call a specific situation ‘a project’? 2. On the basis of which intellectual virtues is the knowledge generated and what is the impact for theory and practice? 3. Are the modes of action of the practitioners ‘prudent’ and are they differentiating or reconciling formal and abstract rationality from substantive rationality and situated reasoning with regards to the mode of action they adopt in particular project situations? The investigation of the above questions leads me to debate about ‘Project Management-as-Praxis’, and to suggest ‘A’ (not ‘THE’) ‘praxeological’ style of reasoning and mode of inquiry – acknowledging a non-paradigmatic, subjective and kaleidoscopic perspective – for ‘Knowing-as-Practicing’ in project management. In short, this is about making a ‘Projects Science’ that matters.
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Awareness to avoid losses and casualties due to rain-induced landslide is increasing in regions that routinely experience heavy rainfall. Improvements in early warning systems against rain-induced landslide such as prediction modelling using rainfall records, is urgently needed in vulnerable regions. The existing warning systems have been applied using stability chart development and real-time displacement measurement on slope surfaces. However, there are still some drawbacks such as: ignorance of rain-induced instability mechanism, mislead prediction due to the probabilistic prediction and short time for evacuation. In this research, a real-time predictive method was proposed to alleviate the drawbacks mentioned above. A case-study soil slope in Indonesia that failed in 2010 during rainfall was used to verify the proposed predictive method. Using the results from the field and laboratory characterizations, numerical analyses can be applied to develop a model of unsaturated residual soils slope with deep cracks and subject to rainwater infiltration. Real-time rainfall measurement in the slope and the prediction of future rainfall are needed. By coupling transient seepage and stability analysis, the variation of safety factor of the slope with time were provided as a basis to develop method for the real-time prediction of the rain-induced instability of slopes. This study shows the proposed prediction method has the potential to be used in an early warning system against landslide hazard, since the FOS value and the timing of the end-result of the prediction can be provided before the actual failure of the case study slope.