74 resultados para 7140-309
Resumo:
This paper presents a method for automatic terrain classification, using a cheap monocular camera in conjunction with a robot’s stall sensor. A first step is to have the robot generate a training set of labelled images. Several techniques are then evaluated for preprocessing the images, reducing their dimensionality, and building a classifier. Finally, the classifier is implemented and used online by an indoor robot. Results are presented, demonstrating an increased level of autonomy.
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Nonhealing wounds are a major burden for health care systems worldwide. In addition, a patient who suffers from this type of wound usually has a reduced quality of life. While the wound healing process is undoubtedly complex, in this paper we develop a deterministic mathematical model, formulated as a system of partial differential equations, that focusses on an important aspect of successful healing: oxygen supply to the wound bed by a combination of diffusion from the surrounding unwounded tissue and delivery from newly formed blood vessels. While the model equations can be solved numerically, the emphasis here is on the use of asymptotic methods to establish conditions under which new blood vessel growth can be initiated and wound-bed angiogenesis can progress. These conditions are given in terms of key model parameters including the rate of oxygen supply and its rate of consumption in the wound. We use our model to discuss the clinical use of treatments such as hyperbaric oxygen therapy, wound bed debridement, and revascularisation therapy that have the potential to initiate healing in chronic, stalled wounds.
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Heat transfer through an attic space into or out of buildings is an important issue for attic-shaped houses in both hot and cold climates. One of the important objectives for design and construction of houses is to provide thermal comfort for occupants. In the present energy-conscious society, it is also a requirement for houses to be energy efficient, i.e. the energy consumption for heating or air-conditioning houses must be minimized. Relevant to these objectives, research into heat transfer in attics has been conducted for about three decades. The transient behaviour of an attic space is directly relevant to our daily life. Certain periods of the day or night may be considered as having a constant ambient temperature (e.g. during 11am - 2pm or 11pm - 2am). However, at other times during the day or night the ambient temperature changes with time (e.g. between 5am - 9am or 5pm - 9pm). Therefore, the analysis of steady state solution is not sufficient to describe the fluid flow and heat transfer in the attic space. The discussion of the transient development of the boundary is required. A theoretical understanding of the transient behaviour of the flow in the enclosure is performed through scaling analysis for sudden and ramp heating conditions. A proper identification of the timescales, the velocity and the thickness relevant to the flow that develops inside the cavity makes it possible to predict theoretically the basic flow features that will survive once the thermal flow in the enclosure reaches a steady state. Those scaling predictions have been verified by a series of numerical simulations.
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There are increasing opportunities in many countries for pre-service teachers to engage in a transnational school-based experience as part of study abroad programmes. The transformative potential of such transnational teaching experiences is recorded in research studies, often supported by data from participant surveys. However, there has been a lack of evidence investigating how shifts in professional understanding derive from such experiences. This qualitative study addresses this issue by exploring the perspectives of 16 pre-service teachers of English as a Second language from Hong Kong, who engaged in transnational teaching activities with primary school pupils in Australia, during their study abroad program. Discourse analysis of participants’ dialogues traces how they encountered conflicting Discourses of ‘student-centredness’ in the Australian classroom. Reflecting dialogically on their experiences led participants to negotiate and reframe their understandings of language teaching pedagogy and themselves as language teachers. The findings demonstrate the importance of both peer and lecturer feedback into the process of dialogic reflection and the need for more longitudinal research into the impact of transnational school-based experience in pre-service teacher education.
Resumo:
Design Science Research (DSR) has emerged as an important approach in Information Systems (IS) research, evidenced by the plethora of recent related articles in recognized IS outlets. Nonetheless, discussion continues on the value of DSR for IS and how to conduct strong DSR, with further discussion necessary to better position DSR as a mature and stable research paradigm appropriate for IS. This paper contributes to address this need, by providing a comprehensive conceptual and argumentative positioning of DSR relative to the core of IS. This paper seeks to argue the relevance of DSR as a paradigm that addresses the core of IS discipline well. Here we use the framework defined by Wand and Weber, to position what the core of IS is.
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The presence of colour in raw sugar plays a key role in the marketing strategy of the Australian raw sugar industry. Some sugars are relatively difficult to decolourise during refining and develop colour during storage. A new approach that might result in efficient and cost-effective colour removal during the sugar manufacturing process is the use of an advanced oxidation process (AOP), known as Fenton oxidation, that is, catalytic production of hydroxyl radicals from the decomposition of hydrogen peroxide using ferrous iron. As a first step towards developing this technology, this study determined the composition of colour precursors present in the juice of cane harvested by three different methods. The methods were harvesting cane after burning, harvesting the whole crop with half of the trash extracted and harvesting the whole crop with no trash extracted. The study also investigated the degradation at pH 3, 4 and 5 of a phenolic compound, caffeic acid (3,4–dihydroxycinnamic acid), which is present in sugar cane juice, using both hydrogen peroxide and Fenton’s reagent. The results show that juice expressed from whole crop cane has significantly higher colour than juices expressed from burnt cane. However, the concentrations of phenolic acids were lower in the juices expressed from whole crop cane. The main phenolic acids present in these juices were p-coumaric, vanillic, 2,3–dihydroxybenzoic, gallic and 3,4–dihydroxybenzoic acids. The degradation of caffeic acid significantly improved using Fenton’s reagent in comparison to hydrogen peroxide alone. The Fenton oxidation was optimum at pH 5 when up to ~86% of caffeic acid degraded within 5 min.
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Objective: This study investigated the characteristics of the patient-practitioner relationship desired by overweight/obese individuals in weight management. The aim was to identify characteristics of the relationship which empower patients to make lifestyle changes. Methods: Grounded theory was used inductively to build a model of the patient-practitioner relationship based on the perspectives of 21 overweight/obese ¬adults. Results: Emerging from the match between patient and practitioner characteristics, collaboration was the key process explicitly occurring in the patient-practitioner relationship, and was characterised by two subcategories; perceived power dimensions and openness. Trust emerged implicitly from the collaborative process, being fostered by relational, informational, and credible aspects of the interaction. Patient trust in their practitioner consequently led to empowering outcomes including goal ownership and perceiving the utility of changes. Conclusion: An appropriate match between patient and practitioner characteristics facilitates collaboration which leads to trust, both of which appear to precede empowering outcomes for patients such as goal ownership and perceiving the utility of changes. Collaboration is an explicit process and precedes the patient trusting their practitioner. Practice implications: Practitioners should be sensitive to patient preferences for collaboration and the opportunity to develop trust with patients relationally, through information provision, and modelling a healthy lifestyle.
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Structure and chemistry of poorly characterized phases (PCP). We suggest here that approximately 10 angstrom PCP, a dominant matrix variety, has a structure equivalent to iron-rich tochilinite [6Fe (sub 0.9) S 5(Fe, Mg) (OH) (sub 2) ] which consists of coherently interstratified mackinawite and brucite sheets. approximately 17 angstrom PCP, previously described as an SBB-type mixed-layer structure, is a commensurate intergrowth of serpentine and tochilinite layers. A wide range of cation substitutions is possible within both tochilinite and serpentine-tochilinite structural types. Various forms of PCP observed in carbonaceous chondrites are intergrowths of tochilinite, serpentine, serpentine-tochilinite and/or valleriite-type minerals.--Modified journal abstract.
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Oprincipal objetivo desse artigo é apresentar os resultados parciais de uma pesquisa em andamento sobre o processo de produção de conteúdo do portal Viva Favela, um dos projetos sociais realizados pela organização nãogovernamental Viva Rio. Partindo de uma abordagem conceitual que discute os modos pelos quais a mídia alternativa e o jornalismo público/jornalismo cívico criam as condições de possibilidade para que uma determinada prática jornalística dê ‘voz’ e ‘empodere’ (empower) moradores de periferias e favelas brasileiras, estamos realizando um estudo das rotinas produtivas do Viva Favela e seus ‘correspondentes comunitários’. O conceito sobre voice, de Jo Tacchi, oferece-nos um embasamento teórico adequado para refletirmos sobre o que vem sendo denominado, nos Estados Unidos, de digital storytelling – as narrativas digitais produzidas com as tecnologias de informação e comunicação para “contar estórias” 1, que são criativamente apropriadas, no Brasil, por moradores das favelas e periferias das regiões metropolitanas.
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This high prevalence of comorbid mental health and substance use disorders makes the accurate diagnosis of comorbid disorders an important clinical priority. However, the presence of comorbid disorders creates a number of diagnostic dilemmas, which have hindered our understanding of the comorbid disorders. This chapter discusses these diagnostic dilemmas, including issues with the reliability, validity and clinical utility of current systems of psychiatric nomenclature’s approach to diagnosing comorbid disorders. A number of alternative models for understanding comorbid disorders are briefly discussed, followed by suggestions for how research can improve our understanding of comorbid disorders.
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Many clinicians in the area of drug addiction believe that emotional problems arise from particular styles of parenting. To investigate this link, 63 young male and female addicts who had sought treatment completed the Parental Bonding Instrument which tapped their perceptions of their relationship with each parent. Addicts reported early parental experiences differing from those of a control group. Drug abusers judged their parents as cold, indifferent, controlling and intrusive. In addition, these perceptions were shared by male and female addicts. These results, together with previous research suggest that these perceptions might well point to a general risk factor for the development of a broad range of psychological and psychiatric disorders. In addition, the issue of family factors in the design and implementation of drug treatment programs needs to be addressed.
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The mineral kovdorskite Mg2PO4(OH)�3H2O was studied by electron microscopy, thermal analysis and vibrational spectroscopy. A comparison of the vibrational spectroscopy of kovdorskite is made with other magnesium bearing phosphate minerals and compounds. Electron probe analysis proves the mineral is very pure. The Raman spectrum is characterized by a band at 965 cm�1 attributed to the PO3� 4 m1 symmetric stretching mode. Raman bands at 1057 and 1089 cm�1 are attributed to the PO3�4 m3 antisymmetric stretching modes. Raman bands at 412, 454 and 485 cm�1 are assigned to the PO3�4 m2 bending modes. Raman bands at 536, 546 and 574 cm�1 are assigned to the PO3�4 m4 bending modes. The Raman spectrum in the OH stretching region is dominated by a very sharp intense band at 3681 cm�1 assigned to the stretching vibration of OH units. Infrared bands observed at 2762, 2977, 3204, 3275 and 3394 cm�1 are attributed to water stretching bands. Vibrational spectroscopy shows that no carbonate bands are observed in the spectra; thus confirming the formula of the mineral as Mg2PO4(OH)�3H2O.
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Climate change is predicted to increase the frequency and severity of extreme weather events which pose significant challenges to the ability of government and other relief agencies to plan for, cope with and respond to disasters. Consequently, it is important that communities in climate sensitive and potential disaster prone areas strengthen their resilience to natural disasters in order to expeditiously recover from potential disruptions and damage caused by disasters. Building self reliance and, particularly in the immediate aftermath of a disaster, can facilitate short-term and long-term community recovery. To build stronger and more resilient communities, it is essential to have a better understanding of their current resilience capabilities by assessing areas of strength, risks and vulnerabilities so that their strengths can be enhanced and the risks and vulnerability can be appropriately addressed and mitigated through capacity building programs. While a number of conceptual frameworks currently exist to assess the resilience level of communities to disasters, they have tended to differ on their emphasis, scope and definition of what constitutes community resilience and how community resilience can be most effectively and accurately assessed. These limitations are attributed to the common approach of viewing community resilience through a mono-disciplinary lens. To overcome this, this paper proposes an integrated conceptual framework that takes into account the complex interplay of environmental, social, governance, infrastructure and economic attributes associated with community resilience. The framework can be operationalised using a range of resilience indicators to suit the nature of a disaster and the specific characteristics of a study region.