4 resultados para critical moments
em CentAUR: Central Archive University of Reading - UK
Resumo:
Demand response is believed by some to become a major contributor towards system balancing in future electricity networks. Shifting or reducing demand at critical moments can reduce the need for generation capacity, help with the integration of renewables, support more efficient system operation and thereby potentially lead to cost and carbon reductions for the entire energy system. In this paper we review the nature of the response resource of consumers from different non-domestic sectors in the UK, based on extensive half hourly demand profiles and observed demand responses. We further explore the potential to increase the demand response capacity through changes in the regulatory and market environment. The analysis suggests that present demand response measures tend to stimulate stand-by generation capacity in preference to load shifting and we propose that extended response times may favour load based demand response, especially in sectors with significant thermal loads.
Resumo:
Despite diversity in family dynamics within and between societies, globally, it is adults who are usually relied upon to care for family members who are sick, disabled or have other care needs. Young people in Zambia and other African countries affected by the HIV epidemic are under increasing pressure to obtain a good education and employment to support their families, whilst some also have to cope with the loss of parents and care for relatives with little external support. This article discusses the findings of qualitative research that explored the experiences of young people (aged 14-30) who had significant family caring responsibilities and those without such responsibilities in Zambia. Interviews and life-mapping methods were conducted with a total of 35 young people living in rural and urban areas, 12 parents and relatives and 12 professionals. We analyse young people's experiences and perceptions of socially expected transitions, such as completing education and earning an income to support themselves and their families, in addition to more unpredictable changes in young people's family lives. ‘Critical moments’ (Thomson et al, 2002), such as bereavement and loss of parents and other family members, disinheritance of assets and property grabbing, migration and mobility between different relatives homes, parental divorce and separation, often had significant impacts on young people’s ability to navigate their pathways to adulthood according to wider social norms and expectations. A more relational conceptualisation of youth transitions is needed that takes account of young people's caring responsibilities and changing family dynamics.
Resumo:
A simple, dynamically consistent model of mixing and transport in Rossby-wave critical layers is obtained from the well-known Stewartson–Warn–Warn (SWW) solution of Rossby-wave critical-layer theory. The SWW solution is thought to be a useful conceptual model of Rossby-wave breaking in the stratosphere. Chaotic advection in the model is a consequence of the interaction between a stationary and a transient Rossby wave. Mixing and transport are characterized separately with a number of quantitative diagnostics (e.g. mean-square dispersion, lobe dynamics, and spectral moments), and with particular emphasis on the dynamics of the tracer field itself. The parameter dependences of the diagnostics are examined: transport tends to increase monotonically with increasing perturbation amplitude whereas mixing does not. The robustness of the results is investigated by stochastically perturbing the transient-wave phase speed. The two-wave chaotic advection model is contrasted with a stochastic single-wave model. It is shown that the effects of chaotic advection cannot be captured by stochasticity alone.