951 resultados para cooperative content distribution


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In this paper we analyse the effects of highway traffic flow parameters like vehicle arrival rate and density on the performance of Amplify and Forward (AF) cooperative vehicular networks along a multi-lane highway under free flow state. We derive analytical expressions for connectivity performance and verify them with Monte-Carlo simulations. When AF cooperative relaying is employed together with Maximum Ratio Combining (MRC) at the receivers the average route error rate shows 10-20 fold improvement compared to direct communication. A 4-8 fold increase in maximum number of traversable hops can also be observed at different vehicle densities when AF cooperative communication is used to strengthen communication routes. However the theorical upper bound of maximum number of hops promises higher performance gains.

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The ABC’s 50-year TV partnership with the BBC is at breaking point after a landmark deal between the British broadcaster and pay TV provider Foxtel was announced in April 2013. Under the new deal Foxtel will host a new BBC channel that will screen first-run, “fast-tracked” British programming, meaning ABC viewers will no longer have free-to-air access to popular shows such as Silent Witness and The Thick of It. The deal between Foxtel and the BBC’s commercial arm, BBC Worldwide, has major implications not only for the two partners, but also for the ABC and potentially for Australian screen content.

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Two of the government’s six media reform bills passed in the House of Representatives with multi-party support on Tuesday 19 March. While most attention and debate has focused on the regulation of the news media and ownership, the changes approved on 19 March are both significant and far-reaching.

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This paper proposes a distributed control approach to coordinate multiple energy storage units (ESUs) to avoid violation of voltage and thermal constraints, which are some of the main power quality challenges for future distribution networks. ESUs usually are connected to a network through voltage source converters. In this paper, both ESU converters active and reactive power are used to deal with the above mentioned power quality issues. ESUs' reactive power is proposed to be used for voltage support, while the active power is to be utilized in managing network loading. Two typical distribution networks are used to apply the proposed method, and the simulated results are illustrated in this paper to show the effectiveness of this approach.

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As a good solution to the shortage and environmental unfriendliness of fossil fuels, plug-in electric vehicles (PEVs) attract much interests of the public. To investigate the problems caused by the integration of numerous PEVs, a lot of research work has been done on the grid impacts of PEVs in aspects including thermal loading, voltage regulation, transformer loss of life, unbalance, losses, and harmonic distortion levels. This paper surveys the-state-of-the-art of the research in this area and outline three possible measures for a power grid company to make full use of PEVs.

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This study is an inquiry into early childhood teacher professional identities. In Australia, workforce reforms in early childhood include major shifts in qualification requirements that call for a university four-year degree-qualified teacher to be employed in child care. This marks a shift in the early years workforce, where previously there was no such requirement. At the same time as these reforms to quality measures are being implemented, and requiring a substantive up skilling of the workforce, there is a growing body of evidence through recent studies that suggests these same four-year degree-qualified early childhood teachers have an aversion to working in child care. Their preferred employment option is to work in the early years of more formal schooling, not in before-school contexts. This collision of agendas warrants investigation. This inquiry is designed to investigate the site at which advocacy for higher qualification requirements meets early childhood teachers who are reluctant to choose child care as a possible career pathway. The key research question for this study is: How are early childhood teachers’ professional identities currently produced? The work of this thesis is to problematise the early childhood teacher in child care through a particular method of discourse analysis. There are two sets of data. The first was a key early childhood political document that read as a "moment of arising" (Foucault, 1984a, p. 83). It is a political document which was selected for its current influence on the early childhood field, and in particular, workforce reforms that call for four-year degree-qualified teachers to work in before-school contexts, including child care. The second data set was generated through four focus group discussions conducted with preservice early childhood teachers. The document and transcripts of the focus groups were both analysed as text, as conceptualised by Foucault (1981). Foucault’s work spans a number of years and a range of philosophical matters. This thesis draws particularly on Foucault’s writings on discourse, power/knowledge, regimes of truth and resistance. In order to consider the production of early childhood teachers’ professional identities, the study is also informed by identity theorists, who have worked on gender, performativity and investment (Davies, 2004/2006; McNay, 1992; Osgood, 2012; Walkerdine, 1990; Weedon, 1997). The ways in which discourses intersect, compete and collide produce the subject (Foucault, 1981) and, in the case of this inquiry, there are a number of competing discourses at play, which produce the early childhood teacher. These particular theories turn particular lenses on the question of professional identities in early childhood, and such a study calls for the application of particular methodologies. Discourse analysis was used as the methodological framework, and the analysis was informed by Foucauldian concepts of discourse. While Foucault did not prescribe a form of discourse analysis as a method, his writings nonetheless provide a valuable framework for illuminating discursive practices and, in turn, how people are affected, through the shifts and distribution of power (Foucault, 1980a). The treatment used with both data sets involved redescription. For the policy document, a technique for reading document-as-text applied a genealogical approach (Foucault, 1984a). For the focus groups, the process of redescription (Rorty, 1989) involved reading talk-as-text. As a method, redescription involves describing "lots and lots of things in new ways until you have created a pattern of linguistic behaviour which will tempt the new generation to adopt it" (Rorty, 1989, p. 9). The development and application of categories (Davies, 2004/2006) built on a poststructuralist theoretical framework and the literature review informed the data analysis method of discourse analysis. Irony provided a rhetorical and playful tool (Haraway, 1991; Rorty, 1989), to look to how seemingly opposing discourses are held together. This opens a space to collapse binary thinking and consider seemingly contradictory terms in a way in which both terms are possible and both are true. Irony resists the choice of one or the other being right, and holds the opposites together in tension. The thesis concludes with proposals for new, ironic categories, which work to bring together seemingly opposing terms, located at sites in the field of early childhood where discourses compete, collide and intersect to produce and maintain early childhood teacher professional identities. The process of mapping these discourses goes some way to investigating the complexities about identities and career choices of early childhood teachers. The category of "the cost of loving" captures the collision between care/love, inherent in child care, and new discourses of investment/economics. Investment/economics has not completely replaced care/love, and these apparent opposites were not read as a binary because both are necessary and both are true (Haraway, 1991). They are held together in tension to produce early childhood teacher professional identities. The policy document under scrutiny was New Directions, released in 2007 by the then opposition ALP leader, Kevin Rudd. The claim was made strongly that the "economic prosperity" of Australia relies on investment in early childhood. The arguments to invest are compelling and the neuroscience/brain research/child development together with economic/investment discourses demand that early childhood is funding is increased. The intersection of these discourses produces professional identities of early childhood teachers as a necessary part of the country’s economy, and thus, worthy of high status. The child care sector and work in child care settings are necessary, with children and the early childhood teacher playing key roles in the economy of the nation. Through New Directions it becomes sayable (Foucault, 1972/1989) that the work the early childhood teacher performs is legitimated and valued. The children are produced as "economic units". A focus on what children are able to contribute to the future economy of the nation re-positions children and produces these "smart productive citizens", making future economic contribution. The early childhood teacher is produced through this image of a child and "the cost of loving" is emphasised. A number of these categories were produced through the readings of the document-as text and the talk-as-text. Two ironic categories were read in the analysis of the transcripts of the focus group discussions, when treated as talk-as-text data: the early childhood teacher as a "heroic victim"; and the early childhood teacher as a "glorified babysitter". This thesis raises new questions about professional identities in early childhood. These new questions might go some way to prompt re-thinking of some government policy, as well as some aspects of early childhood teacher education course design. The images of children and images of child care provide provocations to consider preservice teacher education course design. In particular, how child care, as one of the early childhood contexts, is located, conceptualised and spoken throughout the course. Consideration by course designers and teacher educators of what discourses are privileged in course content —what discourses are diminished or silenced—would go some way to reconceptualising child care within preservice teacher education and challenging dominant ways of speaking child care, and work in child care. This inquiry into early childhood teachers’ professional identities has gone some way to exploring the complexities around the early childhood teacher in child care. It is anticipated that the significance of this study will thus have immediate applicably and relevance for the Australian early childhood policy landscape. The early childhood field is in a state of rapid change, and this inquiry has examined some of the disconnects between policy and practice. Awareness of the discourses that are in play in the field will continue to allow space for conversations that challenge dominant assumptions about child care, work in child care and ways of being an early childhood teacher in child care.

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OBJECTIVE: The objective of this study was to describe the distribution of conjunctival ultraviolet autofluorescence (UVAF) in an adult population. METHODS: We conducted a cross-sectional, population-based study in the genetic isolate of Norfolk Island, South Pacific Ocean. In all, 641 people, aged 15 to 89 years, were recruited. UVAF and standard (control) photographs were taken of the nasal and temporal interpalpebral regions bilaterally. Differences between the groups for non-normally distributed continuous variables were assessed using the Wilcoxon-Mann-Whitney ranksum test. Trends across categories were assessed using Cuzick's non-parametric test for trend or Kendall's rank correlation τ. RESULTS: Conjunctival UVAF is a non-parametric trait with a positively skewed distribution. Median amount of conjunctival UVAF per person (sum of four measurements; right nasal/temporal and left nasal/temporal) was 28.2 mm(2) (interquartile range 14.5-48.2). There was an inverse, linear relationship between UVAF and advancing age (P<0.001). Males had a higher sum of UVAF compared with females (34.4 mm(2) vs 23.2 mm(2), P<0.0001). There were no statistically significant differences in area of UVAF between right and left eyes or between nasal and temporal regions. CONCLUSION: We have provided the first quantifiable estimates of conjunctival UVAF in an adult population. Further data are required to provide information about the natural history of UVAF and to characterise other potential disease associations with UVAF. UVR protective strategies should be emphasised at an early age to prevent the long-term adverse effects on health associated with excess UVR.

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Aim: To describe the recruitment, ophthalmic examination methods and distribution of ocular biometry of participants in the Norfolk Island Eye Study, who were individuals descended from the English Bounty mutineers and their Polynesian wives. Methods: All 1,275 permanent residents of Norfolk Island aged over 15 years were invited to participate, including 602 individuals involved in a 2001 cardiovascular disease study. Participants completed a detailed questionnaire and underwent a comprehensive eye assessment including stereo disc and retinal photography, ocular coherence topography and conjunctival autofluorescence assessment. Additionally, blood or saliva was taken for DNA testing. Results: 781 participants aged over 15 years were seen (54% female), comprising 61% of the permanent Island population. 343 people (43.9%) could trace their family history to the Pitcairn Islanders (Norfolk Island Pitcairn Pedigree). Mean anterior chamber depth was 3.32mm, mean axial length (AL) was 23.5mm, and mean central corneal thickness was 546 microns. There were no statistically significant differences in these characteristics between persons with and without Pitcairn Island ancestry. Mean intra-ocular pressure was lower in people with Pitcairn Island ancestry: 15.89mmHg compared to those without Pitcairn Island ancestry 16.49mmHg (P = .007). The mean keratometry value was lower in people with Pitcairn Island ancestry (43.22 vs. 43.52, P = .007). The corneas were flatter in people of Pitcairn ancestry but there was no corresponding difference in AL or refraction. Conclusion: Our study population is highly representative of the permanent population of Norfolk Island. Ocular biometry was similar to that of other white populations. Heritability estimates, linkage analysis and genome-wide studies will further elucidate the genetic determinants of chronic ocular diseases in this genetic isolate.

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[Extract] For just $5.29 Australians can now purchase "Skins" from local, independent grocers to cover their cigarette packet with the Aboriginal or Torres Strait Islander flag. We argue that this use of cultural content and copyright' imagery on cigarette packets negates health promotion efforts, such as Australia's recent introduction of plain packaging laws and the subsequent dismissal of a legal challenge from the tobacco industry.

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Vacuum cleaners can release large concentrations of particles, both in their exhaust air and from resuspension of settled dust. However, the size, variability and microbial diversity of these emissions are unknown, despite evidence to suggest they may contribute to allergic responses and infection transmission indoors. This study aimed to evaluate bioaerosol emission from various vacuum cleaners. We sampled the air in an experimental flow tunnel where vacuum cleaners were run and their airborne emissions sampled with closed-face cassettes. Dust samples were also 35 collected from the dust bag. Total bacteria, total archaea, Penicillium/Aspergillus and total Clostridium cluster 1 were quantified with specific qPCR protocols and emission rates were calculated. Clostridium botulinum, as well as antibiotic resistance genes were detected in each sample using endpoint PCR. Bacterial diversity was also analyzed using denaturing gel electrophoresis (DGGE), image analysis and band sequencing. We demonstrated that emission of bacteria and moulds (Pen/Asp) can reach values as high as 1E05/min and that those emissions are not related to each other. The bag dust bacterial and mould content was also consistently across the vacuums we assessed, reaching up to 1E07 bacteria or moulds equivalent/g. Antibiotic resistance genes were detected in several samples. No archaea or C. botulinum were detected in any air samples. Diversity analyses showed that most bacteria are from human sources, in keeping with other recent results. These results highlight the potential capability of vacuum cleaners to disseminate appreciable quantities of moulds and human-associated bacteria indoors and their role as a source of exposure to bioaerosols.

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A nanoparticles size is one of their key physical characteristics that can affect their fate in a human’s respiratory tract (in case of inhalation) and also in the environment. Hence, measuring the size distribution of nanoparticles is absolutely essential and contributes greatly to their characterization. For years, Scanning Mobility Particle Sizers (SMPS), which rely on measuring the electrical mobility diameter of particles, have been used as one of the most reliable real-time instruments for the size distribution measurement of nanoparticles. Despite its benefits, this instrument has some drawbacks, including equivalency problems for non-spherical particles (i.e. assuming a non-spherical particle is equal to a spherical particle of diameter d due to the same electrical mobility), as well as limitations in terms of its use in workplaces, because of its large size and the complexity of its operation...

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In this report, a detailed FTIR fitting analysis was used to recognize Mg, Zn and Al homogeneous distribution in MgxZnyAl(x+y)/2-Layered double hydroxide (LDH) hydroxyl layer. In detail, OH-Mg2Al:OH-Mg3 ratios decreased from 95.2:4.8 (MIR) and 94.2:5.8 (NIR) to 58.9:41.1 (MIR) and 61.8:38.2 (NIR), when Mg:Al increased from 2.2:1.0 to 4.1:1.0 in MgAl-LDHs. These fitting results were similar with theoretical calculations of 94.3:5.7 and 59.0:41.0. In a further analysis of MgxZnyAl(x+y)/2-LDHs, OH bonded Zn2Mg, Zn2Al, MgZnAl, Mg2Al and Mg2Zn peaks were identified at 3420, 3430, 3445–3450, 3454 and 3545 cm-1, respectively. With the decrease of Mg:Zn from 3:1 to 1:3, metal-hydroxyl bands changed from OH-Mg2Al and MgZnAl (with a ratio of 49.4:50.6) to OH-MgZnAl and Zn2Al (with a ratio of 55.0:45.0). They were also similar with theoretical calculations of 47.6:52.4 and 54.6:45.4. As a result, these results show that there is an ordered cation distribution in MgxZnyAl(x+y)/2-LDH, and FTIR is feasible in recognizing this structure.

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During food drying, many other changes occur simultaneously, resulting in an improved overall quality. Among the quality attributes, the structure and its corresponding color influence directly or indirectly other properties of food. In addition, these quality attributes are affected by process conditions, material components and the raw structure of the foodstuff. In this work, the temperature distribution within food materials during microwave drying has been taken into consideration to observe its role in color modification. In order to determine the temperature distribution of microwave-dried food (apple), a thermal imaging camera has been used. The image acquired from the digital camera has been analysed using image J software in order to get the color change of fresh and dried apple. The results show that temperature distribution plays an important role in determining the quality of the food. The thermal imaging camera was deployed to observe the temperature distribution within food materials during drying. It is clearly observed from the higher value of (ERGB =102) and the uneven color change that uneven temperature distribution can influence customer perceptions of the quality of dried food. Simulation of a mathematical model of temperature distribution during microwave drying can make it possible to predict the colour and texture of the microwaved food.

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Background Many Australian cities experience large winter increases in deaths and hospitalisations. Flu outbreaks are only part of the problem and inadequate protection from cold weather is a key independent risk factor. Better home insulation has been shown to improve health during winter, but no study has examined whether better personal insulation improves health. Data and Methods We ran a randomised controlled trial of thermal clothing versus usual care. Subjects with heart failure (a group vulnerable to cold) were recruited from a public hospital in Brisbane in winter and followed-up at the end of winter. Those randomised to the intervention received two thermal hats and tops and a digital thermometer. The primary outcome was the number of days in hospital, with secondary outcomes of General Practitioner (GP) visits and self-rated health. Results The mean number of days in hospital per 100 winter days was 2.5 in the intervention group and 1.8 in the usual care group, with a mean difference of 0.7 (95% CI: –1.5, 5.4). The intervention group had 0.2 fewer GP visits on average (95% CI: –0.8, 0.3), and a higher self-rated health, mean improvement –0.3 (95% CI: –0.9, 0.3). The thermal tops were generally well used, but even in cold temperatures the hats were only worn by 30% of subjects. Conclusions Thermal clothes are a cheap and simple intervention, but further work needs to be done on increasing compliance and confirming the health and economic benefits of providing thermals to at-risk groups.

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Current Bayesian network software packages provide good graphical interface for users who design and develop Bayesian networks for various applications. However, the intended end-users of these networks may not necessarily find such an interface appealing and at times it could be overwhelming, particularly when the number of nodes in the network is large. To circumvent this problem, this paper presents an intuitive dashboard, which provides an additional layer of abstraction, enabling the end-users to easily perform inferences over the Bayesian networks. Unlike most software packages, which display the nodes and arcs of the network, the developed tool organises the nodes based on the cause-and-effect relationship, making the user-interaction more intuitive and friendly. In addition to performing various types of inferences, the users can conveniently use the tool to verify the behaviour of the developed Bayesian network. The tool has been developed using QT and SMILE libraries in C++.