871 resultados para Analysis of teaching process


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Long term exposure to vehicle emissions has been associated with harmful health effects. Children are amongst the most susceptible group and schools represent an environment where they can experience significant exposure to vehicle emissions. However, there are limited studies on children’s exposure to vehicle emissions in schools. The aim of this study was to quantify the concentration of organic aerosol and in particular, vehicle emissions that children are exposed to during school hours. Therefore an Aerodyne compact time-of-flight aerosol mass spectrometer (TOF-AMS) was deployed at five urban schools in Brisbane, Australia. The TOF-AMS enabled the chemical composition of the non- refractory (NR-PM1) to be analysed with a high temporal resolution to assess the concentration of vehicle emissions and other organic aerosols during school hours. At each school the organic fraction comprised the majority of NR-PM1 with secondary organic aerosols as the main constitute. At two of the schools, a significant source of the organic aerosol (OA) was slightly aged vehicle emissions from nearby highways. More aged and oxidised OA was observed at the other three schools, which also recorded strong biomass burning influences. Primary emissions were found to dominate the OA at only one school which had an O:C ratio of 0.17, due to fuel powered gardening equipment used near the TOF-AMS. The diurnal cycle of OA concentration varied between schools and was found to be at a minimum during school hours. The major organic component that school children were exposed to during school hours was secondary OA. Peak exposure of school children to HOA occurred during school drop off and pick up times. Unless a school is located near major roads, children are exposed predominately to regional secondary OA as opposed to local emissions during schools hours in urban environments.

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Knowledge is a commodity. It is a by-product of learning that involves the creation, sharing, processing and possible use of information in the mind of an individual. Knowledge management (KM) is, therefore, concerned with the effective implementation of such activities within the organisation. It is simply the process of leveraging organisational knowledge to deliver a long-term competitive advantage. This paper presents the results of an empirical research investigation into the interaction between different KM activities within the context of construction contracting organisations. The different KM activities include: responsiveness to the knowledge of business environment, knowledge acquisition, knowledge dissemination, and knowledge application. A questionnaire survey was administered to investigate the opinions of construction professionals regarding the intensity of activities currently implemented by their organisations to facilitate knowledge capturing, sharing and application. A total of 149 responses were then used to statistically examine the inter-relationships between the different KM activities as practised by contracting organisations in Hong Kong. The paper presents and discusses the survey findings and proposes recommendations for improving the effectiveness of current KM practices.

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Authenticated Encryption (AE) is the cryptographic process of providing simultaneous confidentiality and integrity protection to messages. This approach is more efficient than applying a two-step process of providing confidentiality for a message by encrypting the message, and in a separate pass providing integrity protection by generating a Message Authentication Code (MAC). AE using symmetric ciphers can be provided by either stream ciphers with built in authentication mechanisms or block ciphers using appropriate modes of operation. However, stream ciphers have the potential for higher performance and smaller footprint in hardware and/or software than block ciphers. This property makes stream ciphers suitable for resource constrained environments, where storage and computational power are limited. There have been several recent stream cipher proposals that claim to provide AE. These ciphers can be analysed using existing techniques that consider confidentiality or integrity separately; however currently there is no existing framework for the analysis of AE stream ciphers that analyses these two properties simultaneously. This thesis introduces a novel framework for the analysis of AE using stream cipher algorithms. This thesis analyzes the mechanisms for providing confidentiality and for providing integrity in AE algorithms using stream ciphers. There is a greater emphasis on the analysis of the integrity mechanisms, as there is little in the public literature on this, in the context of authenticated encryption. The thesis has four main contributions as follows. The first contribution is the design of a framework that can be used to classify AE stream ciphers based on three characteristics. The first classification applies Bellare and Namprempre's work on the the order in which encryption and authentication processes take place. The second classification is based on the method used for accumulating the input message (either directly or indirectly) into the into the internal states of the cipher to generate a MAC. The third classification is based on whether the sequence that is used to provide encryption and authentication is generated using a single key and initial vector, or two keys and two initial vectors. The second contribution is the application of an existing algebraic method to analyse the confidentiality algorithms of two AE stream ciphers; namely SSS and ZUC. The algebraic method is based on considering the nonlinear filter (NLF) of these ciphers as a combiner with memory. This method enables us to construct equations for the NLF that relate the (inputs, outputs and memory of the combiner) to the output keystream. We show that both of these ciphers are secure from this type of algebraic attack. We conclude that using a keydependent SBox in the NLF twice, and using two different SBoxes in the NLF of ZUC, prevents this type of algebraic attack. The third contribution is a new general matrix based model for MAC generation where the input message is injected directly into the internal state. This model describes the accumulation process when the input message is injected directly into the internal state of a nonlinear filter generator. We show that three recently proposed AE stream ciphers can be considered as instances of this model; namely SSS, NLSv2 and SOBER-128. Our model is more general than a previous investigations into direct injection. Possible forgery attacks against this model are investigated. It is shown that using a nonlinear filter in the accumulation process of the input message when either the input message or the initial states of the register is unknown prevents forgery attacks based on collisions. The last contribution is a new general matrix based model for MAC generation where the input message is injected indirectly into the internal state. This model uses the input message as a controller to accumulate a keystream sequence into an accumulation register. We show that three current AE stream ciphers can be considered as instances of this model; namely ZUC, Grain-128a and Sfinks. We establish the conditions under which the model is susceptible to forgery and side-channel attacks.

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A dual-scale model of the torrefaction of wood was developed and used to study industrial configurations. At the local scale, the computational code solves the coupled heat and mass transfer and the thermal degradation mechanisms of the wood components. At the global scale, the two-way coupling between the boards and the stack channels is treated as an integral component of the process. This model is used to investigate the effect of the stack configuration on the heat treatment of the boards. The simulations highlight that the exothermic reactions occurring in each single board can be accumulated along the stack. This phenomenon may result in a dramatic eterogeneity of the process and poses a serious risk of thermal runaway, which is often observed in industrial plants. The model is used to explain how thermal runaway can be lowered by increasing the airflow velocity, the sticker thickness or by gas flow reversal.

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Purpose – This paper aims to provide insights into the moral values embodied by a popular social networking site (SNS), Facebook. Design/methodology/approach – This study is based upon qualitative fieldwork, involving participant observation, conducted over a two-year period. The authors adopt the position that technology as well as humans has a moral character in order to disclose ethical concerns that are not transparent to users of the site. Findings – Much research on the ethics of information systems has focused on the way that people deploy particular technologies, and the consequences arising, with a view to making policy recommendations and ethical interventions. By focusing on technology as a moral actor with reach across and beyond the internet, the authors reveal the complex and diffuse nature of ethical responsibility and the consequent implications for governance of SNS. Research limitations/implications – The authors situate their research in a body of work known as disclosive ethics, and argue for an ongoing process of evaluating SNS to reveal their moral importance. Along with that of other authors in the genre, this work is largely descriptive, but the paper engages with prior research by Brey and Introna to highlight the scope for theory development. Practical implications – Governance measures that require the developers of social networking sites to revise their designs fail to address the diffuse nature of ethical responsibility in this case. Such technologies need to be opened up to scrutiny on a regular basis to increase public awareness of the issues and thereby disclose concerns to a wider audience. The authors suggest that there is value in studying the development and use of these technologies in their infancy, or if established, in the experiences of novice users. Furthermore, flash points in technological trajectories can prove useful sites of investigation. Originality/value – Existing research on social networking sites either fails to address ethical concerns head on or adopts a tool view of the technologies so that the focus is on the ethical behaviour of users. The authors focus upon the agency, and hence the moral character, of technology to show both the possibilities for, and limitations of, ethical interventions in such cases.

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A range of authors from the risk management, crisis management, and crisis communications literature have proposed different models as a means of understanding components of crisis. A generic component of these sources has focused on preparedness practices before disturbance events and response practices during events. This paper provides a critical analysis of three key explanatory models of how crises escalate highlighting the strengths and limitations of each approach. The paper introduces an optimised conceptual model utilising components from the previous work under the four phases of pre-event, response, recovery, and post-event. Within these four phases, a ten step process is introduced that can enhance understanding of the progression of distinct stages of disturbance for different types of events. This crisis evolution framework is examined as a means to provide clarity and applicability to a range of infrastructure failure contexts and provide a path for further empirical investigation in this area.

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In this study we develop a theorization of an Internet dating site as a cultural artifact. The site, Gaydar, is targeted at gay men. We argue that contemporary received representations of their sexuality figure heavily in the site’s focus by providing a cultural logic for the apparent ad hoc development trajectories of its varied commercial and non-­‐commercial services. More specifically, we suggest that the growing sets of services related to the website are heavily enmeshed within current social practices and meanings. These practices and meanings are, in turn, shaped by the interactions and preferences of a variety of diverse groups involved in what is routinely seen within the mainstream literature as a singularly specific sexuality and cultural project. Thus, we attend to two areas – the influence of the various social engagements associated with Gaydar together with the further extension of its trajectory ‘beyond the web’. Through the case of Gaydar, we contribute a study that recognizes the need for attention to sexuality in information systems research and one which illustrates sexuality as a pivotal aspect of culture. We also draw from anthropology to theorize ICTs as cultural artifacts and provide insights into the contemporary phenomena of ICT enabled social networking.

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The Action Lecture program is an innovative teaching method run in some nursery and primary schools in Paris and designed to improve pupils’ literacy. We report the results of an evaluation of this program. We describe the experimental protocol that was built to estimate the program’s impact on several types of indicators. Data were processed following a Differences-in-Differences (DID) method. Then we use the estimation of the impact on academic achievement to conduct a cost-effectiveness analysis and take a reduction of the class size program as a benchmark. The results are positive for the Action Lecture program.

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This dissertation investigates the nature of power in university-industry linkages and how such power affects the process of knowledge production in engaged scholarship. The most critical finding of this dissertation is that the theory of engaged scholarship fails to account for the socialised beliefs regarding the superior value of academic knowledge, which governs the behaviour and perceptions of academics and industry partners within university-industry linkages. The dissertation is supported by data sourced from interviews with 48 academic and industry partners’ project leaders from 24 large scale research projects and thematic analysis guided by Steven Lukes’ (1974) radical framework of power.

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In late 2007, newly elected Prime Minister Kevin Rudd placed education reform on centre stage as a key policy in the Labor Party's agenda for social reform in Australia. A major policy strategy within this 'Education Revolution' was the development of a national curriculum, the Australian Curriculum Within this political context, this study is an investigation into how social justice and equity have been used in political speeches to justify the need for, and the nature of, Australia's first official national curriculum. The aim is to provide understandings into what is said or not said; who is included or excluded, represented or misrepresented; for what purpose; and for whose benefit. The study investigates political speeches made by Education Ministers between 2008 and 201 0; that is, from the inception of the Australian Curriculum to the release of the Phase 1 F - 10 draft curriculum documents in English, mathematics, science and history. Curriculum development is defined here as an ongoing process of complex conversations. To contextualise the process of curriculum development within Australia, the thesis commences with an initial review of curriculum development in this nation over the past three decades. It then frames this review within contemporary curriculum theory; in particular it calls upon the work of William Pinar and the key notions of currere and reconceptualised curriculum. This contextualisation work is then used as a foundation to examine how social justice and equity have been represented in political speeches delivered by the respective Education Ministers Julia Gillard and Peter Garrett at key junctures of Australian Curriculum document releases. A critical thematic policy analysis is the approach used to examine selected official speech transcripts released by the ministerial media centre through the DEEWR website. This approach provides a way to enable insights and understandings of representations of social justice and equity issues in the policy agenda. Broader social implications are also discussed. The project develops an analytic framework that enables an investigation into the framing of social justice and equity issues such as inclusion, equality, quality education, sharing of resources and access to learning opportunities in political speeches aligned with the development of the Australian Curriculum Through this analysis, the study adopts a focus on constructions of educationally disadvantaged students and how the solutions of 'fixing' teachers and providing the 'right' curriculum are presented as resolutions to the perceived problem. In this way, it aims to work towards offering insights into political justifications for a national curriculum in Australia from a social justice perspective.

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Background The delivery of quality patient care in the emergency department (ED) is emerging as one of the most important service indicators to be measured in health services today. The emergency nurse practitioner role was implemented as a service innovation in a Emergency & Trauma Centre (ETC), Melbourne, Australia, in July 2004 .The primary aim of the role was intended to enhance healthcare services, improve the efficiency and timely delivery of high quality care to patients. Aim To conduct a retrospective study of patient presentations at the ETC to obtain a profile of the characteristics of patients managed by emergency nurse practitioners. Specifically the objectives of the study were to: 1) examine the demographics of the patient population 2) evaluate data on emergency department service indicators for this patient cohort Method All patients presenting to the ETC from January 01 2011 to December 31 2011 and managed by emergency nurse practitioners were included in the review. Data collection included baseline demographics, waiting times to be seen, length of stay, emergency department discharge diagnoses and referral patterns. Data were extracted and imported directly from the emergency department Patient Information System (Cerner log), for the specified time frame. Results A total of 5212 patients were reviewed in the study period. The median age of patients was 35 years and 61% of patients were male. The most common discharge diagnosis was open wounds to hand/wrist. Waiting times to be seen by the emergency nurse practitioner were 14 minutes and length of stay for patients with a discharge disposition of home were 122 minutes. Conclusions This study has provided information on patient baseline characteristics and performance on important service indicators for this patient sample that will inform further research to evaluate specific outcomes of the emergency nurse practitioner service.

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Aerosol mass spectrometers (AMS) are powerful tools in the analysis of the chemical composition of airborne particles, particularly organic aerosols which are gaining increasing attention. However, the advantages of AMS in providing on-line data can be outweighed by the difficulties involved in its use in field measurements at multiple sites. In contrast to the on-line measurement by AMS, a method which involves sample collection on filters followed by subsequent analysis by AMS could significantly broaden the scope of AMS application. We report the application of such an approach to field studies at multiple sites. An AMS was deployed at 5 urban schools to determine the sources of the organic aerosols at the schools directly. PM1 aerosols were also collected on filters at these and 20 other urban schools. The filters were extracted with water and the extract run through a nebulizer to generate the aerosols, which were analysed by an AMS. The mass spectra from the samples collected on filters at the 5 schools were found to have excellent correlations with those obtained directly by AMS, with r2 ranging from 0.89 to 0.98. Filter recoveries varied between the schools from 40 -115%, possibly indicating that this method provides qualitative rather than quantitative information. The stability of the organic aerosols on Teflon filters was demonstrated by analysing samples stored for up to two years. Application of the procedure to the remaining 20 schools showed that secondary organic aerosols were the main source of aerosols at the majority of the schools. Overall, this procedure provides accurate representation of the mass spectra of ambient organic aerosols and could facilitate rapid data acquisition at multiple sites where AMS could not be deployed for logistical reasons.

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Recently we reported the presence of bacteria within follicular fluid. Previous studies have reported that DNA fragmentation in human spermatozoa after in vivo or in vitro incubation with bacteria results in early embryo demise and a reduced rate of ongoing pregnancy, but the effect of bacteria on oocytes is unknown. This study examined the DNA within mouse oocytes after 12 hours’ incubation within human follicular fluids (n = 5), which were collected from women undergoing in vitro fertilization (IVF) treatment. Each follicular fluid sample was cultured to detect the presence of bacteria. Terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL) was used to label DNA fragmentation in ovulated, non-fertilized mouse oocytes following in vitro incubation in human follicular fluid. The bacteria Streptococcus anginosus and Peptoniphilus spp., Lactobacillus gasseri (low-dose), L. gasseri (high-dose), Enterococcus faecalis, or Propionibacterium acnes were detected within the follicular fluids. The most severe DNA fragmentation was observed in oocytes incubated in the follicular fluids containing P. acnes or L. gasseri (high-dose). No DNA fragmentation was observed in the mouse oocytes incubated in the follicular fluid containing low-dose L. gasseri or E. faecalis. Low human oocyte fertilization rates (<29%) were associated with extensive fragmentation in mouse oocytes (80–100%). Bacteria colonizing human follicular fluid in vivo may cause DNA fragmentation in mouse oocytes following 12 h of in vitro incubation. Follicular fluid bacteria may result in poor quality oocytes and/or embryos, leading to poor IVF outcomes.

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The incidence of Squamous Cell Carcinoma (SCG) is growing in certain populations to the extent that it is now the most common skin lesion in young men and women in high ultraviolet exposure regions such as Queensland. In terms of incidence up to 40% of the Australian population over 40 years of age is thought to possess the precancerous Solar Keratosis (SK) lesion and with a small, but significant, chance of progression into SCC, understanding the genetic events that play a role in this process is essential. The major aims of this study were to analyse whole blood derived samples for DNA aberrations in genes associated with tumour development and cellular maintenance, with the ultimate aim of identifying genes associated with non-melanoma skin cancer development. More specifically the first aim of this project was to analyse the SDHD and MMP12 genes via Dual-Labelled Probe Real-Time PCR for copy number aberrations in an affected Solar Keratosis and control cohort. It was found that 12 samples had identifiable copy-number aberrations in either the SDHD or MMP12 gene (this means that a genetic section of either of these two genes is aberrantly amplified or deleted), with five of the samples exhibiting aberrations in both genes. The significance of this study is the contribution to the knowledge of the genetic pathways that are malformed in the progression and development of the pre-cancerous skin lesion Solar Keratosis. © 2008 Springer Science+Business Media, LLC.

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This article presents the first narrative analysis of the areas of research that have developed within the destination marketing field since its commencement in 1973. Given the broad extent of the field, and the absence of any previous reviews in four decades, a key challenge is in providing a focus for such a disparate body of knowledge. The review is structured around one principal question: ‘To what extent is the Destination Marketing Organisation (DMO) responsible for the competitiveness of the destination’? In pursuit of this underlying question, we address a number of themes including nomenclature and the DMO, the evolution of the destination marketing literature, competitiveness as the DMO reason d’être, and DMO effectiveness including issues of branding and positioning, and future research themes in the field.