Motion and performance analysis of an experimental model floating wind turbine

Laboratory measurements of the motion and rotor performance of a model floating wind turbine were undertaken under simple wind and wave conditions. The model consisted of a 40cm diameter rotor mounted on a fully submerged cylinder supported vertically by four arms to form a tension leg floater. The laboratory facility involved a low-wind speed straight-through wind tunnel assembled on the water wave generator. The turbine was connected to a DC generator and an electrical variable-resistance load to vary the rotor speed. Tests were undertaken for one fixed wind speed, varying the rotor tip speed ratio and wave conditions. Four different one-dimensional wave conditions were considered, each with a different wavelength and frequency. Sensors were installed to measure the unsteady wave height and surge of the turbine platform. Other sensors were installed to measure the rotor speed and the generator output power. The measurements show the effects of rotor tip speed ratio and wave condition on the surge motion of the floater. The presence of aerodynamic damping due to the turbine was evident for certain wave conditions. The rotor experienced considerable deviations in the power coefficient characteristics when subjected to waves. The deviations were larger at and above the optimal tip speed ratio. Good agreement was obtained when the measurements for the power coefficient and surge displacement were compared with those from a simplified mathematical model. The model was based on the Blade-Element Momentum theory for rotor aerodynamics and on the Morison equation for the hydrodynamic forces on the floater.peer-reviewe

Videogame soundscapes

This paper proposes a methodological framework to analyze the sonic output of computer games by investigating and adapting available soundscape studies, as discussed primarily by R. Murray Schafer and Barry Truax. While the current academic research about sound in games highlighted the problematic nature of the application of film sound theory to videogames (Jørgensen 2007, 2009, 2011; Collins 2007), this paper considers studies concerning videogame audio, soundscapes and acoustic ecology (Grimshaw 2007; Grimshaw and Schott 2007; O' Keefe 2011; Droumeva 2011) by re-focusing the attention on existing soundscape methodologies, analyzing their theoretical validity and the productiveness of such an approach. By critically considering Truax (2001) analysis of an arcade game room soundscape, videogames will be repositioned by considering them objects for meaningful acoustic communication. An analysis of the sonic environment actualized by the videogame player during a play session is performed, identifying the key features (keynote sounds, sound signals and soundmarks) and the level of definition of a videogame soundscape (high or low definition). Examples are based on modern games such as Street Fighter IV (Capcom 2009) and Grand Theft Auto IV (Rockstar Games 2008), as well as classic titles like Pac-Man (Namco 1980) and Bomberman (Hudson Soft 1983).peer-reviewe

What do healthcare professionals want from a resource to support person-centred conversations on physical activity? A mixed-methods, user-centric approach to developing educational resources.

Objectives: Healthcare is a fundamental action area in population efforts to address the global disease burden from physical inactivity. However, healthcare professionals lack the knowledge, skills and confidence to have regular conversations about physical activity. This study aimed to: (1) understand the requirements of healthcare professionals and patients from a resource to support routine physical activity conversations in clinical consultations and (2) develop such a resource. Methods: This study used codesign principles across two phases, actively involving relevant stakeholders in an iterative development process. The preparatory phase included a scoping literature review and workshops with multidisciplinary healthcare professionals and patients. The Delphi phase included the development of a draft resource, a three-stage modified online Delphi study and an external review. Results: The scoping review highlighted the importance of addressing time restrictions, a behaviour change skill deficit, the need for resources to fit into existing systems and meeting patient expectations. Consultation included 69 participants across two clinical workshops. They recommended using the internet, valued guidance on all aspects of physical activity conversations and were concerned about how to use a person-centred approach. The Delphi phase, including 15 expert participants, met agreement criteria in two stages to develop the resource. Conclusion: This mixed-methods study delivered an online resource that was codesigned with and based on the requirements of healthcare professionals and patients. The resource presents condition-specific ‘1-minute’, ‘5-minute’ and ‘more minute’ person-centred and evidence-based conversation templates on physical activity in an accessible and usable format to meet the needs of real-life clinical practice

A novel spatiotemporal home heating controller design: system emulation and field testing

We have developed a spatiotemporal heating control algorithm for use in homes. This system utilises a combination of relatively low-tech hardware interfaced with electric heating systems and a smartphone interface to this hardware, and a central server that progressively learns users’ room-specific presence profiles and thermal preferences. This paper describes the associated spatiotemporal heating control algorithm, its evaluation utilising the dynamic building performance simulation software EnergyPlus, and a longitudinal deployment of the algorithm controlling a quasi-autonomous spatiotemporal home heating system in three domestic homes. In this we focus on the prediction of occupants’ presence and preferred set-point temperature as well as on the calculation of optimum start time and the utilisation of user-scheduled absences; this for two comfort strategies: to maximise comfort and to minimise discomfort. The former aims to deliver conditions equating to a ‘neutral’ thermal sensation, whereas the latter targets a ‘slightly cool’ sensation with corresponding heating energy savings. Simulation results confirmed that the algorithm functions as intended and that it is capable of reducing energy demand by a factor of seven compared with EnergyStar recommended settings for programmable thermostats. Field study results align with these findings and highlight the possibility to reduce energy under the minimise discomfort strategy without compromising on occupants’ thermal comfort