Unsteady wake modelling for tidal current turbines

The authors present a numerical model for three-dimensional unsteady wake calculations for tidal turbines. Since wakes are characterised by the shedding of a vortex sheet from the rotor blades, the model is based on the vorticity transport equations. A vortex sheet may be considered a jump contact discontinuity in tangential velocity with, in inviscid hydrodynamic terms, certain kinematic and dynamic conditions across the sheet. The kinematic condition is that the sheet is a stream surface with zero normal fluid velocity; the dynamic condition is that the pressure is equal on either side of the sheet. The dynamic condition is explicitly satisfied at the trailing edge only, via an approximation of the Kutta condition. The shed vorticity is the span-wise derivative of bound circulation, and the trailed vorticity is the time derivative of bound circulation, and is convected downstream from the rotors using a finite-volume solution of vorticity transport equations thus satisfying the kinematic conditions. Owing to an absence in the literature of pressure data for marine turbines, results from the code are presented for the NREL-UAE Phase IV turbine. Axial flow cases show a close match in pressure coefficients at various spanwise stations; however, yawed flow cases demonstrate the shortcomings of a modelling strategy lacking viscosity

Economic development in Maine: the Piscataquis county model

Not long ago, few people would have regarded Piscataquis County as an economic development model, but today it is charting a new course for rural Maine.Economic development - Maine ; Rural development - Maine

Educational Technology Topic Guide

This guide aims to contribute to what we know about the relationship between educational technology (edtech) and educational outcomes by addressing the following overarching question: What is the evidence that the use of edtech, by teachers or students, impacts teaching and learning practices, or learning outcomes? It also offers recommendations to support advisors to strengthen the design, implementation and evaluation of programmes that use edtech. We define edtech as the use of digital or electronic technologies and materials to support teaching and learning. Recognising that technology alone does not enhance learning, evaluations must also consider how programmes are designed and implemented, how teachers are supported, how communities are developed and how outcomes are measured (see http://tel.ac.uk/about-3/, 2014). Effective edtech programmes are characterised by: a clear and specific curriculum focus the use of relevant curriculum materials a focus on teacher development and pedagogy evaluation mechanisms that go beyond outputs. These findings come from a wide range of technology use including: interactive radio instruction (IRI) classroom audio or video resources accessed via teachers’ mobile phones student tablets and eReaders computer-assisted learning (CAL) to supplement classroom teaching. However, there are also examples of large-scale investment in edtech – particularly computers for student use – that produce limited educational outcomes. We need to know more about: how to support teachers to develop appropriate, relevant practices using edtech how such practices are enacted in schools, and what factors contribute to or mitigate against successful outcomes. Recommendations: 1. Edtech programmes should focus on enabling educational change, not delivering technology. In doing so, programmes should provide adequate support for teachers and aim to capture changes in teaching practice and learning outcomes in evaluation. 2. Advisors should support proposals that further develop successful practices or that address gaps in evidence and understanding. 3. Advisors should discourage proposals that have an emphasis on technology over education, weak programmatic support or poor evaluation. 4. In design and evaluation, value-for-money metrics and cost-effectiveness analyses should be carried out

The involvement of users in the design of home use medical devices: challenges and incentives for change

The prevalence and use of medical devices in the home environment continues to grow in the United Kingdom (UK) and Worldwide. It is recognised that such devices offer significant benefits to both patients and the National Health Service in the UK. The design of home use medical devices however represents a considerable challenge to designers and manufacturers alike. Developing devices that are usable and understandable by inexperienced, lay or dexterity impaired users requires an understanding across a breadth of disciplines. Previous research in this field has explored these challenges in attempt to offer support for developers of home use medical devices. There have been very few studies however that have explored whether the design community actually need, want or use such guidance, before considering whether this literature is adopted correctly. Through case studies, an online survey and in depth interviews this thesis suggests that industry practitioners are sceptical of the value of design guidance towards user involvement in home use medical device design. Consequently the practitioners in this research make little or no use of the formal design methods and supportive guidance documents available to them. More typically, practitioners in the home use medical device field use their own personal experiences and knowledge from working in the industry to adapt their own approaches to design. This thesis reports that the greatest challenge to involving users in the design of home use medical devices are the internal corporate and traditionally hierarchical barriers between stakeholders within the design process. In contrast to previous research offering support for designers and developers of home use medical devices this thesis calls for a wider change in design practice to facilitate the application of usability principles. As a conclusion to this thesis, recommendations for further research to address these changes in practice are proposed to industry professionals in the medical device industry. This thesis is submitted as part of the requirement for the Degree of Doctor of Philosophy at Loughborough University

Nipped in the Budd? Assessing the wisdom of the Gambling Review Body’s recommendations in relation to problem gambling

The convening of the Gambling Review Body (the ‘Review Body’), between 2000 and 2001 was the most recent attempt by the British Government to consider fully policy objectives for the operation of its licensed gambling market. It followed in a tradition of comprehensive Government-sponsored reviews of gambling (carried out in the twentieth century by Royal Commissions) approximately every 20 to 25 years. The publication of its report in 2001 had a strong influence on the drafting of the Gambling Act 2005 (the ‘2005 Act’), Britain’s principal piece of gambling legislation. In 2019, Britain’s gambling laws are under review once more. The Labour Party (at the date of writing, the principal political party of Opposition) has set out plans for “a new Gambling Act that is fit for the digital age” ; while the House of Lords has approved a special inquiry committee on the “”Social and Economic consequences of the gambling industry ”. Against this backdrop, there may be merit in revisiting Budd. This essay considers two of the Budd Report’s key aims – the protection of vulnerable people and the protection of children[1]. It reviews those recommendations that were explicitly directed towards harm prevention; as well as a number of broader proposals which have clear relevance to the subject. This essay reviews Budd’s recommendations from 2001 against subsequent events – and in particular asks the question of whether the report contributed to the development of future regulatory problems and political controversies

Case History — Performance Monitoring Success

The City Creek Center urban redevelopment project in Salt Lake City, Utah involved excavations up to 65 feet deep. Shoring systems included more than 29,000 square feet of anchored diaphragm walls, 100,000 square feet of soil nail walls, and 860 linear feet of underpinning. Detailed performance monitoring alerted the project team to unacceptable performance of an anchored diaphragm wall adjacent to an occupied twenty-five-story building on shallow foundations. This knowledge allowed the team to react quickly, stabilize the excavation, investigate the situation, and develop successful remedial measures. The diaphragm wall was reinforced with additional anchors and subgrade concrete struts, allowing the excavation to proceed with minimal delay and no damage to the adjacent building

Spatio-temporal influence of tundra snow properties on Ku-band (17.2 GHz) backscatter

During the 2010/11 boreal winter, a distributed set of backscatter measurements was collected using a ground-based Ku-band (17.2 GHz) scatterometer system at 26 open tundra sites. A standard snow-sampling procedure was completed after each scan to evaluate local variability in snow layering, depth, density and water equivalent (SWE) within the scatterometer field of view. The shallow depths and large basal depth hoar encountered presented an opportunity to evaluate backscatter under a set of previously untested conditions. Strong Ku-band response was found with increasing snow depth and snow water equivalent (SWE). In particular, co-polarized vertical backscatter increased by 0.82 dB for every 1 cm increase in SWE (R2 = 0.62). While the result indicated strong potential for Ku-band retrieval of shallow snow properties, it did not characterize the influence of sub-scan variability. An enhanced snow-sampling procedure was introduced to generate detailed characterizations of stratigraphy within the scatterometer field of view using near-infrared photography along the length of a 5m trench. Changes in snow properties along the trench were used to discuss variations in the collocated backscatter response. A pair of contrasting observation sites was used to highlight uncertainties in backscatter response related to short length scale spatial variability in the observed tundra environment

Nanomaterial structure determination using XUV diffraction

Diffraction using coherent XUV radiation is used to study the structure of nanophotonic materials, in this case an ordered array of 196nm spheres. Crystal structure and defects are visible, and the nanomaterial dielectric constant determined