849 resultados para blended


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One of the main challenges learners of Arabic as a foreign language face in Australia is the lack of opportunities to practice the language with native speakers of Arabic outside the classroom boundaries to enhance their language skills in general and their oral proficiency in particular. Learners have so little exposure to Arabic outside the classroom. This restriction in L2 exposure in the formal academic framework is due to the limited face-to-face learning time and, more significantly, is compounded by lack of exposure to the language’s authentic use settings. Students are often isolated from the target language’s authentic discourse communities and native speakers. This situation is exacerbated for Cloud (online) students studying in relative isolation. All of these factors make developing communicative oral fluency in Modern Standard Arabic (MSA) more difficult and challenging for many learners, particularly for Cloud learners. Deakin University is the only university in Australia that offers Arabic in both Campus and Cloud modes of delivery. This paper discusses an innovative approach used at Deakin University to enable online learners of Arabic to practice their developing skills by listening, practicing, and experiencing directly how the language is used outside the classroom boundaries. In addition to providing Cloud learners with an Arabic online environment rich with interactive opportunities to practice the language, it was also necessary to provide the learners with tools such as the virtual classrooms, chat rooms, discussion forums and social media language partner programs, to practice their oral fluency and enrich their learning experience.

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Titanium and grey cast iron powders were blended and deposited by plasma transferred arc onto mild steel substrates. The powders were injected directly into the arc by a stream of inert gas. The grey cast iron provided the iron matrix and the excess carbon content for reaction and precipitation of titanium carbides. The microstructure of the overlay was analysed by optical microscopy and scanning electron microscopy, and the respective phases were identified by X-ray diffraction. Microhardness measurements were taken from representative areas and the wear behaviour was assessed under low-stress abrasion conditions. The results show that the addition of titanium produced a significant change in the microstructure of the overlays, increased surface hardness and enhanced wear resistance compared to overlays produced without titanium.

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L’intégration des nouvelles technologies en enseignement supérieur ne devrait pas être vue comme un simple effet de mode, mais plutôt comme un cadre de réflexion sur les orientations nouvelles à donner à l’Université du 21ème siècle, en termes de culture institutionnelle, de ressources organisationnelles et d’opérationnalisation d’objectifs de recherche et d’enseignement (Duderstadt et al, 2002 ; Guri-Rosenblit, 2005). En effet, l’émergence d’une nouvelle tendance de formation post-secondaire, qu’est l’intégration des solutions virtuelles au présentiel, n’est pas sans incidences sur les pratiques enseignantes. Or, la littérature n’offre pas de modèles descriptifs satisfaisants permettant de mieux saisir la pertinence des liens entre l’enseignement en contexte d’apprentissage hybride et le développement professionnel des enseignants universitaires. Aussi avons-nous procédé par des observations participantes de deux cours en sciences de la gestion à HEC Montréal, dans les programmes de certificat de premier cycle ainsi que par des entretiens d’explicitation et d’autoconfrontation, pendant toute la session d’automne 2014, pour respectivement recueillir des données sur les pratiques réelles d’un maître d’enseignement, en sociologie du travail, et d’une chargée de cours, en gestion de projets. Notre analyse du corpus, par catégorisations conceptualisantes, a permis la production d’énoncés nomologiques rendant compte de la dynamique de relations entre ces deux phénomènes. Sur le plan scientifique, elle a apporté un éclairage nouveau sur les processus de construction identitaire professionnelle en pédagogie universitaire, en regard des mutations technologiques, socioculturelles et économiques que subissent l’Université, en général, et les pratiques enseignantes et étudiantes, en particulier. L’approche inductive utilisée a donc permis de définir la structure des interactions des deux phénomènes, selon la perspective des deux enseignants, et d’élaborer des modèles d’intervention enracinés dans leurs pratiques quotidiennes. Aussi sur le plan social, ces modèles sont-ils l’expression d’une grammaire de la pensée et de l’action, ancrée dans les valeurs des enseignants eux-mêmes. Nous avons pris en compte le paradigme de la tâche réelle, versus celui de la tâche prescrite, en termes de mise en œuvre concrète des processus pédagogiques, pour rendre les résultats de cette recherche signifiants pour la pratique. Les modèles, qui ont émergé de notre configuration de la pensée dialogique des participants, peuvent être intégrés à la formation des enseignants universitaires en contexte de bimodalisation de l’Université.

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L'industrie du ciment est l'une des principales sources d'émission de dioxyde de carbone. L'industrie mondiale du ciment contribue à environ 7% des émissions de gaz à effet de serre dans l'atmosphère. Afin d'aborder les effets environnementaux associés à la fabrication de ciment exploitant en permanence les ressources naturelles, il est nécessaire de développer des liants alternatifs pour fabriquer du béton durable. Ainsi, de nombreux sous-produits industriels ont été utilisés pour remplacer partiellement le ciment dans le béton afin de générer plus d'économie et de durabilité. La performance d'un additif de ciment est dans la cinétique d'hydratation et de la synergie entre les additions et de ciment Portland. Dans ce projet, deux sous-produits industriels sont étudiés comme des matériaux cimentaires alternatifs: le résidu de silice amorphe (RSA) et les cendres des boues de désencrage. Le RSA est un sous-produit de la production de magnésium provenant de l'Alliance Magnésium des villes d'Asbestos et Thedford Mines, et les cendres des boues de désencrage est un sous-produit de la combustion des boues de désencrage, l'écorce et les résidus de bois dans le système à lit fluidisé de l'usine de Brompton située près de Sherbrooke, Québec, Canada. Récemment, les cendres des boues de désencrage ont été utilisées comme des matériaux cimentaires alternatifs. L'utilisation de ces cendres comme matériau cimentaire dans la fabrication du béton conduit à réduire la qualité des bétons. Ces problèmes sont causés par des produits d'hydratation perturbateurs des cendres volantes de la biomasse quand ces cendres sont partiellement mélangées avec du ciment dans la fabrication du béton. Le processus de pré-mouillage de la cendre de boue de désencrage avant la fabrication du béton réduit les produits d'hydratation perturbateurs et par conséquent les propriétés mécaniques du béton sont améliorées. Les approches pour étudier la cendre de boue de désencrage dans ce projet sont : 1) caractérisation de cette cendre volante régulière et pré-humidifiée, 2) l'étude de la performance du mortier et du béton incorporant cette cendre volante régulière et pré-humidifiée. Le RSA est un nouveau sous-produit industriel. La haute teneur en silice amorphe en RSA est un excellent potentiel en tant que matériau cimentaire dans le béton. Dans ce projet, l'évaluation des RSA comme matériaux cimentaires alternatifs compose trois étapes. Tout d'abord, la caractérisation par la détermination des propriétés minéralogiques, physiques et chimiques des RSA, ensuite, l'optimisation du taux de remplacement du ciment par le RSA dans le mortier, et enfin l'évaluation du RSA en remplacement partiel du ciment dans différents types de béton dans le système binaire et ternaire. Cette étude a révélé que le béton de haute performance (BHP) incorporant le RSA a montré des propriétés mécaniques et la durabilité, similaire du contrôle. Le RSA a amélioré les propriétés des mécaniques et la durabilité du béton ordinaire (BO). Le béton autoplaçant (BAP) incorporant le RSA est stable, homogène et a montré de bonnes propriétés mécaniques et la durabilité. Le RSA avait une bonne synergie en combinaison de liant ternaire avec d'autres matériaux cimentaires supplémentaires. Cette étude a montré que le RSA peut être utilisé comme nouveaux matériaux cimentaires dans le béton.

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Objectives: to evaluate the cognitive learning of nursing students in neonatal clinical evaluation from a blended course with the use of computer and laboratory simulation; to compare the cognitive learning of students in a control and experimental group testing the laboratory simulation; and to assess the extracurricular blended course offered on the clinical assessment of preterm infants, according to the students. Method: a quasi-experimental study with 14 Portuguese students, containing pretest, midterm test and post-test. The technologies offered in the course were serious game e-Baby, instructional software of semiology and semiotechnique, and laboratory simulation. Data collection tools developed for this study were used for the course evaluation and characterization of the students. Nonparametric statistics were used: Mann-Whitney and Wilcoxon. Results: the use of validated digital technologies and laboratory simulation demonstrated a statistically significant difference (p = 0.001) in the learning of the participants. The course was evaluated as very satisfactory for them. The laboratory simulation alone did not represent a significant difference in the learning. Conclusions: the cognitive learning of participants increased significantly. The use of technology can be partly responsible for the course success, showing it to be an important teaching tool for innovation and motivation of learning in healthcare.

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For the activated carbon (AC) production, we used the most common industrial and consumer solid waste, namely polyethyleneterephthalate (PET), alone or blended with other synthetic polymer such polyacrylonitrile (PAN). By mixing PET, with PAN, an improvement in the yield of the AC production was found and the basic character and some textural and chemical properties were enhanced. The PET–PAN mixture was subjected to carbonisation, with a pyrolysis yield of 31.9%, between that obtained with PET (16.9%) or PAN (42.6%) separately. The AC revealed a high surface area (1400, 1230 and 1117 m2 g−1) and pore volume (0.46, 0.56 and 0.50 cm3 g−1), respectively, for PET, PAN and PET–PAN precursors. Selected ACs were successfully tested for 4- chloro-2-methylphenoxyacetic acid (MCPA) and diuron removal from the liquid phase, showing a higher adsorption capacity (1.7 and 1.2 mmol g−1, respectively, for MCPA and diuron) and good fits with the Langmuir (PET) and Freundlich equation (PAN and PET–PAN blend). With MCPA, the controlling factor to the adsorption capacity was the porous volume and the average pore size. Concerning diuron, the adsorption was controlled essentially by the external diffusion. A remarkable result is the use of different synthetic polymers wastes, as precursors for the production of carbon materials, with high potential application on the pesticides removals from the liquid phase.

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The production of AC was achieved using the most common industrial and consumer solid waste, namely PET, alone or blended with other synthetic polymer such PAN. The PET-PAN mixture (1:1 W/W %) was subjected to carbonization, with a pyrolysis yield off 31.9%, between that obtained with PET (16.9%) or PAN (42.6%) separately. By mixing PET, as a raw material, with PAN (different ratio), an improvement in the final yield of the AC production, for the same activation time, with CO2, was found.

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The production of AC was achieved using the most common industrial and consumer solid waste, namely PET, alone or blended with other synthetic polymer such PAN. The PET-PAN mixture (1:1 W/W %) was subjected to carbonization, with a pyrolysis yield off 31.9%, between that obtained with PET (16.9%) or PAN (42.6%) separately. By mixing PET, as a raw material, with PAN (different ratio), an improvement in the final yield of the AC production, for the same activation time, with CO2, was found.

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The production of activated carbons (ACs) involves two main steps: the carbonization of the carbonaceous of raw materials at temperatures below 1073 K in the absence of oxygen and the activation had realized at the temperature up to 1173 but the most useful temperature at 1073 K. In our study we used the most common industrial and consumer solid waste, namely PET, alone or blended with other synthetic polymer PAN. By mixing the two polymers in different ratios, an improvement of the yield of the AC production was found and some textural properties were enhanced by comparison with the AC prepared using each polymer separately. When all the samples were exposed through the carbonization process with a pyrolysis the mixture of PAN-PET (1:1w/w) yield around 31.9%, between that obtained with PET (16.9%) or PAN (42.6%) separately. The combine activation, with CO2 at 1073 K, allow ACs with a lower burn-off degree isothermally, when compared with those attained with PET or PAN alone, but with similarly chemicals or textural properties. The resultant ACs are microporous in their nature, as the activation time increase, the PET-PAN mixture AC are characterized by a better developed porous structure, when associated with the AC prepared from PAN. The AC prepared from PET-PAN mixture are characterized by basic surface characteristics, with a pHpzc around 10.5, which is an important characteristic for future applications on acidic pollutants removals from liquid or gaseous phase. In this study we had used the FTIR methods to determine the main functional groups in the surface of the activated carbons. The adsorbents prepared from PAN fibres presents an IR spectrum with similar characteristics to those obtained with PET wastes, but with fewer peaks and bands with less intensity, in particular for the PAN-8240 sample. This can be reflected by the stretching and deformation modes of NH bond in the range 3100 – 3300 cm-1 and 1520 – 1650 cm-1, respectively. Also, stretching mode associated to C–N, C=N, can contributed to the profile of IR spectrum around 1170 cm-1, 1585 – 1770 cm-1. And the TGA methods was used to study the loses of the precursors mass according to the excessive of the temperature. The results showed that, there were different decreasing of the mass of each precursors. PAN degradation started at almost 573 K and at 1073 K, PAN preserve more than 40% of the initial mass. PET degradation started at 650 K, but at 1073 K, it has lost 80% of the initial mass. However, the mixture of PET-PAN (1:1w/w) showed a thermogravimetric profile between the two polymers tested individually, with a final mass slightly less than 30%. From a chemical point of view, the carbonisation of PET mainly occurs in one step between 650 and 775 K.