533 research outputs found

    Evaporation of a thin droplet on a thin substrate with a high thermal resistance

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    A mathematical model for the quasi-steady evaporation of a thin liquid droplet on a thin substrate that incorporates the dependence of the saturation concentration of vapour at the free surface of the droplet on temperature is used to examine an atypical situation in which the substrate has a high thermal resistance relative to the droplet (i.e. it is highly insulating and/or is thick relative to the droplet). In this situation diffusion of heat through the substrate is the rate-limiting evaporative process and at leading order the local mass flux is spatially uniform, the total evaporation rate is proportional to the surface area of the droplet, and the droplet is uniformly cooled. In particular, the qualitative differences between the predictions of the present model in this situation and those of the widely used 'basic' model in which the saturation concentration is independent of temperature are highlighted

    Shared Education in contested spaces: How collaborative networks improve communities and schools

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    Societies which suffer from ethnic and political divisions are often characterised by patterns of social and institutional separation, and sometimes these divisions remain even after political conflict has ended. This has occurred in Northern Ireland where there is, and remains, a long-standing pattern of parallel institutions and services for the different communities. A socially significant example lies in the education system where a parallel system of Catholic and Protestant schools has been in place since the establishment of a national school system in the 1830s. During the years of political violence in Northern Ireland a variety of educational interventions were implemented to promote reconciliation, but most of them failed to create any systemic change. This paper describes a post-conflict educational initiative known as Shared Education which aims to promote social cohesion and school improvement by encouraging sustained and regular shared learning between students and broader collaboration between teachers and school leaders from different schools. The paper examines the background to work on Shared Education, describes a ‘sharing continuum’ which emerged as an evaluation and policy tool from this work and considers evidence from a case study of a Shared Education school partnership in a divided city in Northern Ireland. The paper will conclude by highlighting some of the significant social and policy impact of the Shared Education work

    The Rotating Quantum Thermal Distribution

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    We show that the rigidly rotating quantum thermal distribution on flat space-time suffers from a global pathology which can be cured by introducing a cylindrical mirror if and only if it has a radius smaller than that of the speed-of-light cylinder. When this condition is met, we demonstrate numerically that the renormalized expectation value of the energy-momentum stress tensor corresponds to a rigidly rotating thermal bath up to a finite correction except on the mirror where there are the usual Casimir divergences.Comment: 8 pages, 2 PostScript figure

    The Renormalized Stress Tensor in Kerr Space-Time: Numerical Results for the Hartle-Hawking Vacuum

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    We show that the pathology which afflicts the Hartle-Hawking vacuum on the Kerr black hole space-time can be regarded as due to rigid rotation of the state with the horizon in the sense that when the region outside the speed-of-light surface is removed by introducing a mirror, there is a state with the defining features of the Hartle-Hawking vacuum. In addition, we show that when the field is in this state, the expectation value of the energy-momentum stress tensor measured by an observer close to the horizon and rigidly rotating with it corresponds to that of a thermal distribution at the Hawking temperature rigidly rotating with the horizon.Comment: 17 pages, 7 figure

    Light Therapy Treatment Using Quiet Motors and Remote Control

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    A final year Electrical Engineering student worked with Camphill Community to develop a quiet motor system to adjust the blinds in a light therapy treatment room for people with cerebral palsy.https://arrow.tudublin.ie/civpostbk/1013/thumbnail.jp

    Observation

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    Observation – get engagement with group learning process, group discussions and self- directed phase. Their actions dictate learning. The tutor must try to gauge learning through monitoring interaction

    Spatial Thinking in the Engineering Curriculum: an Investigation of the Relationship Between Problem Solving and Spatial Skills Among Engineering Students.

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    Long considered a primary factor of intelligence, spatial ability has been shown to correlate strongly with success in engineering education, yet is rarely included as a learning outcome in engineering programmes. A clearer understanding of how and why spatial ability impacts on performance in science, technology, engineering and mathematics (STEM) subjects would allow educators to determine if spatial skills development merits greater priority in STEM curricula. The aim of this study is to help inform that debate by shedding new light on the role of spatial thinking in STEM learning and allow teaching practice and curriculum design to be informed by evidence based research. A cross cutting theme in STEM education – problem solving – is examined with respect to its relationship with spatial ability. Several research questions were addressed that related to the role and relevance of spatial ability to first year engineering education and, more specifically, the manner in which spatial ability is manifest in the representation and solution of word story problems in mathematics. Working with samples of engineering students in Ireland and the United States, data were collected in the form of responses to spatial ability tests and problem solving exercises in the areas of mathematics and electric circuits. Following a pilot study to select and refine a set of mathematical story problems a mixed methods design was followed in which data were first analysed using quantitative methods to highlight phenomena that were then explored using an interpretive approach. With regard to engineering education in general, it was found that spatial ability cannot be assumed to improve as students progress through an engineering programme and that spatial ability is highly relevant to assessments that require reasoning about concepts, novel scenarios and problems but can remain hidden in overall course grades possibly due to an emphasis on assessing rote learning. With regard to problem solving, spatial ability was found to have a significant relationship with the problem representation step but not with the solution step. Those with high levels of spatial ability were more able to apply linguistic and schematic knowledge to the problem representation phase which led to higher success rates in translating word statements to mathematical form

    Improving the Quality of PBL Modules in an Engineering Programme

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    Engineering programmes have a strong reputation in the delivery of technical knowledge and skills. Graduates need equally high levels of competence in personal and professional skills to not only improve themselves and meet the existing requirements of employers and professional bodies but to also help them manage the inevitable changes that society is facing in an increasingly populated world. The need to move from traditional to student-centred learning in the context of engineering education was the motivation for this project. This can be facilitated through the use of group-based,problem –driven learning as this offers high integration of technical and non-technical knowledge and skills and requires more engagement with the programme from today’s students. The School of Electrical Engineering Systems in the DIT now delivers a number of engineering modules in this format but experience has shown that it takes a significant amount of time for students to develop personal skills to a high degree. The aim of this project was to develop additional group learning modules and enhance existing ones to pay more attention to personal development. Each of the first three years of the Bachelor of Electrical Engineering programme now contains a group-based module in which learning is project or problem driven and the tutor pays significant attention to personal skills. The concept of progressive development of personal skills was also investigated and a framework to develop these in a structured way through the delivery of group based modules was proposed. The development of further group learning modules and an examination of the effectiveness of this framework will form the basis for continuing this project into the future
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