A coarse grid extraction of sound signals for computational aeroacoustics

Sound waves are propagating pressure fluctuations, which are typically several orders of magnitude smaller than the pressure variations in the flow field that account for flow acceleration. On the other hand, these fluctuations travel at the speed of sound in the medium, not as a transported fluid quantity. Due to the above two properties, the Reynolds averaged Navier–Stokes equations do not resolve the acoustic fluctuations. This paper discusses a defect correction method for this type of multi-scale problems in aeroacoustics. Numerical examples in one dimensional and two dimensional are used to illustrate the concept. Copyright (C) 2002 John Wiley & Sons, Ltd.

An acoustic correction method for extracting sound signals

Sound waves are propagating pressure fluctuations and are typically several orders of magnitude smaller than the pressure variations in the flow field that account for flow acceleration. On the other hand, these fluctuations travel at the speed of sound in the medium, not as a transported fluid quantity. Due to the above two properties, the Reynolds averaged Navier-Stokes (RANS) equations do not resolve the acoustic fluctuations. Direct numerical simulation of turbulent flow is still a prohibitively expensive tool to perform noise analysis. This paper proposes the acousticcorrectionmethod, an alternative and affordable tool based on a modified defect correction concept, which leads to an efficient algorithm for computational aeroacoustics and noise analysis.

Distress in children with learning disabilities at a respite unit: perspective on their experiences

Numerous studies have investigated the benefits of respite to families with a disabled child. Far fewer have examined the effects on the child and none have systematically compared information about this from different sources. Reports of behavioural reactions and views on distress were gathered from parents, teachers and respite staff. Children were also asked for their views. Over half the children (54%) were reported to show medium or strong negative reactions lasting for 1 or more days by a parent or teacher. Reported reactions varied widely between home and school and no concordance was found between parents, teachers and respite staff groups regarding distress. Some children's views differed from those of their parent or teacher. The findings highlight the extent of differences in perspectives and suggest the need for greater awareness of the possible distress to children attending respite. This is discussed in relation to factors such as the potential conflict of interests between parents and children, communication and behavioural difficulties, and the context in which the child is observed.

Spank performance tour [at Signals 07 arts festival]

Spank follows the journeys of two women as they reveal stories from private and public sources set apart by two centuries. It investigates notions of 'faction' and what is filtered out historically within a theme of female trauma and the body. [ABSTRACT BY THE AUTHOR]

Coping, conversation tactics and marital interaction in persons with acquired profound hearing loss (APHL): correlates of distress

This study investigated coping strategies, conversation tactics, and marital interaction in acquired profound hearing loss (APHL) and compared emotionally stable (n = 15) and emotionally distressed (n = 7) participants. Nominated family members were assessed on most measures. Comparisons were also made in the subgroup of married participants. A combined distress criterion was derived from scores on standardized measures of anxiety, depression, hearing handicap, and post-traumatic stress. Groups were compared on the Ways-of-Coping Checklist, a newly devised measure of conversation tactics, and on the Couple Behaviour Report. It was found that distressed APHL participants were more likely to cope through avoidance, self-blame, and wishful thinking, and they used more avoidant tactics in conversation. The coping profile of family members did not differentiate distress groups. However, there was some indication of greater employment of coercive tactics by family members of distressed participants. The results are consistent with the view that the coping style of a person with APHL and the nature of their conversational interactions with family members contribute to their level of distress. Implications for audiological rehabilitation are discussed.

Characterising noise signals in 2-phase solid gas flows

Pneumatic conveying of powder and granular material involve the mixed flow of solid particles in air. Characterisation of solid/gas flow regimes is important for the design, operation and control of plants involving such two-phase processes. This paper describes preliminary studies directed at identifying flow regimes in solid/gas flows by analysis of the process `noise' signals from a flow transmitter which has a relatively wide frequency response.