Rosalyn A. V. Robison

Dynamics of viscous grounding lines

We have used viscous fluids in simple laboratory experiments to explore the dynamics of grounding lines between marine ice sheets and the freely floating ice shelves into which they develop. We model the ice sheets as shear-dominated gravity currents, and the ice shelves as extensional gravity currents having zero shear to leading order. We consider the flow of viscous fluid down an inclined plane into a dense inviscid ‘ocean’. A fixed flux of fluid is supplied at the top of the plane, which is at ‘sea level’. The fluid forms a gravity current flowing down and attached to the plane for some distance before detaching to form a freely floating extensional current. We have derived a mathematical model of the flow that incorporates a new dynamic boundary condition for the position of the grounding line, where the gravity current loses contact with the solid base. The grounding line initially advances and eventually reaches a steady position. Good agreement between our theoretical predictions and experimental measurements and observations gives confidence in the fundamental assumptions of our model.

Balancing Boundaries: Using Multiple Devices to Manage Work-Life Balance

Information and communication technologies (ICTs) continue to give us increased flexibility about when and where we choose to work and the freedom to deal with home tasks whilst at work. However more use of ICT for work during non-work time has been linked with negative outcomes including lower work and life satisfaction and increased stress. Previous work has suggested that in order to reduce some of these negative effects, people should adopt technology use strategies that aid separation of their home and work lives. In this paper we report the results of a questionnaire study investigating work-life balance boundary behaviours and technology use. We find that people use multiple devices as a way of creating boundaries between home and work, and the extent to which they do this relates to their boundary behaviour style. These findings have particular relevance given the increasing trend for Bring Your Own Device (BYOD) policies.

Propeller Unsteady Distortion Noise

Turbulence, as naturally occurs in the atmosphere, is known to become highly anisotropic in the presence of the flow induced by a propeller. This turbulent distortion, caused by the streamtube contraction, significantly affects the tonal content of the radiated noise due to turbulence ingestion. We present here an analytic framework in which turbulent distortion may be assessed for any irrotational mean flow which approaches uniform axial flow far upstream. Sound spectra are presented for the case of two rotors in close proximity, for which the distortion is asymmetric. Quantities such as the turbulence spectrum at the rotor face and sound directivity then vary with azimuthal angle �.

Constructing policy success for UK energy feedback

ABSTRACT Energy-feedback tools are commonly used to promote energy saving. In the UK, energy-feedback provision (currently via an in-home display) is part of the government-mandated roll-out of smart meters to all homes by 2020. A core assumption underlying this widespread provision is that information, or evidence, can lead to positive changes in action. This is analogous to assumptions underlying the notion of ‘evidence-based policy’, and raises questions about how users, researchers and policy-makers go about using evidence when aiming for a ‘successful’ outcome. In addition, the ‘policy feedback’ research agenda has asked how policies alter the landscapes within which they operate by, for example, affecting relationships between actors. Via an in-depth review of Department of Energy and Climate Change (DECC) policy literature over 2010–16, the UK smart meter roll-out was analysed in terms of how its energy-feedback-focused measures may be deemed as ‘successful’. Findings include the fact that direct energy savings played a smaller role than might be expected, and translation from one success measure to another was repeatedly observed. A key conclusion is that acting on feedback requires an assessment of success, but such assessment is highly contextual, for consumers and policy-makers alike. Ways to increase reflexivity in this area are discussed.