47 research outputs found

    Engaging children in meaningful charity: opening-up the spaces within which children learn to give

    Get PDF
    This paper presents qualitative evidence from an in-depth, participative action research project with 150 children aged 4-8 years old, exploring their experiences, perceptions and preferences regarding charitable giving. Most children positively engage in charitable giving through home, school and their community, however less than 20% are aware of the cause area they are being asked to support, and most have little decision-making in their giving. Children鈥檚 willingness to engage increases when they critically examine the cause area and are facilitated to lead on giving decisions, often resulting in increased and sustained efforts to support cause areas that matter to them

    Predicting Academic Performance: A Systematic Literature Review

    Get PDF
    The ability to predict student performance in a course or program creates opportunities to improve educational outcomes. With effective performance prediction approaches, instructors can allocate resources and instruction more accurately. Research in this area seeks to identify features that can be used to make predictions, to identify algorithms that can improve predictions, and to quantify aspects of student performance. Moreover, research in predicting student performance seeks to determine interrelated features and to identify the underlying reasons why certain features work better than others. This working group report presents a systematic literature review of work in the area of predicting student performance. Our analysis shows a clearly increasing amount of research in this area, as well as an increasing variety of techniques used. At the same time, the review uncovered a number of issues with research quality that drives a need for the community to provide more detailed reporting of methods and results and to increase efforts to validate and replicate work.Peer reviewe

    The Prediction of Surface Temperature in Drilling of Ti6Al4V

    No full text
    Titanium and its alloys are attractive materials due to their unique high strength-weight ratio that is maintained at elevated temperatures and their exceptional corrosion resistance. The major application of titanium has been in the aerospace industry. However, the focus shift of market trends from military to commercial and aerospace to industry also been reported. On the other hand, titanium and its alloys are notorious for their poor thermal properties and are classified as difficult-to-machine materials. These properties limit the use of these materials especially in the markets where cost is much more of a factor than in aerospace. Machining is an important manufacturing process because it is almost always involved if precision is required and is the most effective process for small volume production. Due to the low machinability of the alloys under study, selecting the machining conditions and parameters is crucial. The range of feeds and cutting speeds, which provide a satisfactory tool life, is very limited. On the other hand, adequate tool, coating, geometry and cutting flow materials should be used: otherwise, the high wear of the tool, and the possible tolerance errors, would introduce unacceptable flaws in parts that require a high degree of precision. In this study, heat changes of Ti6Al4V has been examined on the basis of cutting parameters such as depth of cut, feedrate and cutting speed during drilling. Heat changes of the material and tool was monitored by a thermal camera. Maximum temperatures of the experiments were taken to examine optimum cutting parameters. Obtained results have been used to generate a regression analysis and it is seen that regression has given accurate data.Tytan i jego stopy to atrakcyjne materia艂y ze wzgl臋du na ich unikalnie wysoki stosunek wytrzyma艂o艣ci do ci臋偶aru w艂a艣ciwego, utrzymywany w podwy偶szonej temperaturze i ich wyj膮tkow膮 odporno艣膰 na korozj臋. G艂贸wnym zastosowaniem tytanu jest przemys艂 lotniczy. Jednak zmiana trend贸w na rynku z wojskowego na cywilny i z przemys艂u lotniczego na inne ga艂臋zie przemys艂u jest r贸wnie偶 obserwowana. Z drugiej strony tytan i jego stopy s膮 znane z ich s艂abych w艂a艣ciwo艣ci termicznych i s膮 klasyfikowane jako materia艂y trudne w obr贸bce. W艂a艣ciwo艣ci te ograniczaj膮 wykorzystywanie tych materia艂贸w zw艂aszcza na rynkach, na kt贸rych koszt jest znacznie wi臋kszym czynnikiem ni偶 w przemy艣le lotniczym. Obr贸bka mechaniczna jest wa偶nym procesem wytwarzania, poniewa偶 prawie zawsze ma miejsce, je偶eli wymagana jest precyzja i jest to najbardziej skuteczny spos贸b wytwarzania ma艂ych obj臋to艣ci. Ze wzgl臋du na nisk膮 obrabialno艣膰 stop贸w badanych, dob贸r warunk贸w obr贸bki i parametr贸w jest krytyczny. Zakres posuw贸w i pr臋dko艣ci skrawania, kt贸re zapewniaj膮 zadowalaj膮c膮 trwa艂o艣膰 narz臋dzia, jest bardzo ograniczony. Z drugiej strony, nale偶y stosowa膰 odpowiedni materia艂 narz臋dzia, pow艂oki, geometri臋, w przeciwnym razie wysokie zu偶ycie narz臋dzia i ewentualne b艂臋dy tolerancji wprowadz膮 niedopuszczalne b艂臋dy w cz臋艣ciach kt贸re wymagaj膮 wysokiego stopnia precyzji. W pracy badano zmiany cieplne w stopach Ti6A14V wynikaj膮ce z parametr贸w ci臋cia takich jak g艂臋boko艣膰 skrawania, posuw i pr臋dko艣膰 skrawania podczas wiercenia. Zmiany cieplne materia艂u i narz臋dzia monitorowano za pomoc膮 kamery termicznej. Maksymalne warto艣ci temperatury eksperyment贸w zosta艂y dobrane w celu zbadania optymalnych parametr贸w skrawania. Otrzymane wyniki wykorzystano do analizy regresji i jest widoczne, 偶e regresja daje dok艂adne dane
    corecore