This paper addresses two typically separate issues contributing to urban quality of life: increasing noise levels and declining quality of public green space. Drawing from environmental psychology, ecology and acoustical methods, this interdisciplinary research studied the soundscapes of three green spaces in a UK city through interviews with 70 park users, the measurement of habitat and recording of sound levels. The data reveal a prevalence of mechanical sounds and a hierarchy of preference for natural over people and mechanical sounds. There was a link between sound levels, both objective and perceived, and the type of sounds heard. The presence of these sounds varied across sites in part due to the ecological qualities of the place, specifically the presence of birds and shrub vegetation. The results suggest that people's opportunity to access quiet, natural places in urban areas can be enhanced by improving the ecological quality of urban green spaces through targeted planning and design.

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The dynamic control of daylight is seen as key for the effective exploitation of natural illumination in buildings. Traditional control solutions are invariably used in a sub-optimal manner: blinds/shades are left down for long periods and lights are left switched on. A glazing with a transmissivity that varies continuously between clear and dark extremes, and which can be controlled automatically, could be much more effective in providing a 'well-tempered' daylit environment that meets occupants needs. Amongst the different types of variable transmission glazing that have undergone extensive research and development in the last few decades, those based on electrochromism appear to have the best performance characteristics and the greatest market potential. Electrochromic (EC) glazing generally exhibits a shift in spectral transmission as the glass darkens, e.g. causing it to appear blue as it tints. Occupants, however, are believed to prefer a neutral spectrum of daylight illumination without any pronounced hue. In this paper, the authors show that it is possible to maintain a neutral spectrum of illumination with electrochromic (EC) glazing under normal operation provided that just a small proportion of the EC glazing is kept in the clear state. A theoretical model to predict the daylight spectrum resulting from any arbitrary combination of clear and tinted glazing is described. Predictions from the model are compared with measurements of the daylight spectra in an office with EC glazing under various states of tint. The predicted spectra show excellent agreement with the measurements. The model is applicable to any combination of clear and/or tinted glass panels irrespective of the glazing type(s). The paper concludes with a discussion of design considerations for the effective deployment of EC glazing.

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A technique to measure arbitrarily complex luminous fluxes across large areas is presented. The technique is founded on high dynamic range imaging technology and can be achieved using a standard consumer digital camera and everyday materials such as printer-grade white paper. The same approach can also be used to determine the direct and diffuse components of illuminance. The technique has been named transmission illuminance proxy -high dynamic range imaging or TIP-HDRI.