922017 research outputs found
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Application of URANS turbulence closure models to complex flows subjected to electromagnetic and other body forces
No full textThis paper considers the application of the Reynolds Averaged Navier-Stokes (RANS) approach to two types of electromagnetically influenced turbulent flows. The first is a fully-developed 2D channel flow with a magnetic field imposed in either the wall-normal direction (Hartmann Flow), or in the streamwise direction. The second is that of Rayleigh-Benard convection with a vertical magnetic field imposed. The turbulence is represented by a low-Re k-epsilon model which is tested with and without electromagnetic modifcations proposed by Kenjeres and Hanjalic (2000). The results show tha modifications lead to a dramatic reorganisation of the coherent structures in Rayleigh-Benard convection as the magnetic field strength is increased, but over-predict the damping of the turbulent shear stress in a simple channel flow
H εκπαίδευση στην κοινωνική εργασία την εποχή της κρίσης στην Ελλάδα: εκπαιδεύοντας το ανθρώπινο δυναμικό να καταπολεμήσει τις ανισότητες
No full textSince 2010, Greece has experienced an unprecedented economic and humanitarian crisis, which continues to have tremendous social impact. Austerity measures and policy cuts have included a dis-investment in social work and social care and more recently the abolition of one of the four national Social Work Departments providing qualifying social work education. In this context, this study addresses the following question: how does pre-qualifying social work education in Greece influence students’ ability to manage value tensions in relation to anti-oppressive practice? Using a case study methodology, the research was based in one Social Work Department (subsequently abolished). Data were collected through semi-structured interviews from social work students at two points in their professional education (n=32) and once from academic staff/placement supervisors (n=10). Data were analysed drawing on grounded theory techniques. In this paper only one particular dataset is considered in detail: the attitudes and experiences of final year students. The main findings indicate students’ narrow understandings and individualistic approaches towards oppression, reflecting an urgent need to redefine social work education and practice in Greece according to current social justice concerns. Specifically, social work education needs to give greater weight to a structural perspective on the dynamics of oppression
On the approximate zeroth and first order consistency in the presence of irregular boundaries in SPH obtained by the virtual boundary particle methods
No full text
Application of URANS turbulence closure models to complex flows subjected to electromagnetic and other body forces
No full textThis paper considers the application of the Reynolds Averaged Navier-Stokes (RANS) approach to two types of electromagnetically influenced turbulent flows. The first is a fully-developed 2D channel flow with a magnetic field imposed in either the wall-normal direction (Hartmann Flow), or in the streamwise direction. The second is that of Rayleigh-Benard convection with a vertical magnetic field imposed. The turbulence is represented by a low-Re k-epsilon model which is tested with and without electromagnetic modifcations proposed by Kenjeres and Hanjalic (2000). The results show tha modifications lead to a dramatic reorganisation of the coherent structures in Rayleigh-Benard convection as the magnetic field strength is increased, but over-predict the damping of the turbulent shear stress in a simple channel flow
Modelling, assessment and Sankey diagrams of integrated electricity-heat-gas networks in multi-vector district energy systems
Full text linkThe widespread use of decentralised multi-energy supply solutions such as gas-fired Combined Heat and Power (CHP), heat pumps, gas boilers, and so forth is more and more increasing the linkages between electricity, heat and gas distribution networks. However, there is currently no model able to model the three networks in an integrated manner and with a suitable level of detail for operational purposes. A multi-temporal simulation model, which has been implemented in a relevant MATLAB-Excel VBA tool, is presented in this paper to carry out integrated analysis of electricity, heat and gas distribution networks, with specific applications to multi-vector district energy systems. The network linkages have been modelled through a multi-vector efficiency matrix specifically developed to map the transformation of final demands into network energy flows while taking into account the inter-network locations of the individual supply technologies. The relevant coupled electrical, heat and gas flow equations have been solved simultaneously using a Newton-Raphson approach. A real case study of a district multi-energy system in the Campus of the University of Manchester illustrates the quantitative use of the model in different scenarios for technical, economic and environmental studies. Sankey diagrams of the energy flows across the networks are also presented to give a visual picture of the multi-energy interactions and losses in the district in different scenarios. The model can be flexibly adapted to generic network topologies and multi-energy supply technologies, and can thus be used for practical operational implementations as well as to inform planning of low carbon multi-vector energy systems
Linking adaptation science to action to build food secure Pacific Island communities
No full textClimate change is a major threat to food security in Pacific Island countries, with declines in food production and increasing variability in food supplies already evident across the region. Such impacts have already led to observed consequences for human health, safety and economic prosperity. Enhancing the adaptive capacity of Pacific Island communities is one way to reduce vulnerability and is underpinned by the extent to which people can access, understand and use new knowledge to inform their decision-making processes. However, effective engagement of Pacific Island communities in climate adaption remains variable and is an ongoing and significant challenge. Here, we use a qualitative research approach to identify the impediments to engaging Pacific Island communities in the adaptations needed to safeguard food security. The main barriers include cultural differences between western science and cultural knowledge, a lack of trust among local communities and external scientists, inappropriate governance structures, and a lack of political and technical support. We identify the importance of adaptation science, local social networks, key actors (i.e., influential and trusted individuals), and relevant forms of knowledge exchange as being critical to overcoming these barriers. We also identify the importance of co-ordination with existing on-ground activities to effectively leverage, as opposed to duplicating, capacity
Evaluating the Economical Benefits of using Buckling-Restrained Braces in Hospital Structures
No full textValue assessment and quantitative benefit-risk modelling of biosimilar infliximab for Crohn’s disease
No full textAim: Regulatory approval of biosimilars often depends on extrapolating evidence from one clinical indication to all of those of the originator biologic. We aimed to develop a quantitative benefit-risk analysis to assess whether the resulting increase in the uncertainty in the clinical performance of biosimilars (i.e. risk) may be countered by their lower pricing (benefit).Methods: A one-year decision-analytic model was developed for the biosimilar infliximab (Inflectra®) for Crohn’s disease. The perspective was that of the NHS in the UK and costs were valued to 2015/16. A hypothetical cohort of biologic-naïve patients with moderate-to-severe Crohn’s disease were simulated through the model. Immunogenicity to infliximab was a key modifier, influencing rates of non-response and infusion reactions. Net health benefit was estimated based on quality-adjusted life years (QALYs). A range of sensitivity analyses tested the robustness of the results and explored how the biosimilar price must respond to varying immunogenicity to remain the preferred option. Results: The base-case analysis predicted a positive incremental net health benefit of 0.04 (95% Central Range 0.00-0.09) favouring the biosimilar, based on 0.803 QALYs, and costs of £18,087 and £19,176 for biosimilar and originator, respectively. Two-way sensitivity analyses suggested that if 50% of patients developed antibodies, the value-based price of £410 per vial must be lower than that of the originator (£420), but remain higher than the actual market price (£378). Conclusions: The model supports the use of Inflecta® for Crohn’s disease in the UK, and provides a framework for the quantitative evaluation of biosimilars in the context of health technology assessment. Value-based pricing using this methodology could protect health systems from the potential risks of biosimilars where they are untested in the approved populations.<br/
