A mixed methods approach to urban ecosystem services: experienced environmental quality and its role in ecosystem assessment within an inner-city estate

This paper contributes to the notion of ecosystem services (ES) and dis-services (EDS) through an exploration of how they are experienced in an inner-city neighbourhood. We contrast the findings of a science-led assessment with qualitative interview and visual data from the residents of the Woodberry Down Estate (London, UK). We use the ontology of co-production and co-construction to understand how material and interpretative factors condition the translation of identified service-providing units (SPUs) into directly experienced ES and EDS. Findings demonstrate that aspects contributing to the perceived liveability of a neighbourhood also condition the experienced ES and EDS. In our case study, the history of the estate translates into subjective feelings of safety which influence whether individuals access parts of the regenerated estate. While the regeneration project provides a broad range of new and improved SPUs with significant ES potential, the access and recreational functions these offer are especially appreciated for the increased opportunities for social interaction and visitors they provide. However, new SPUs such as landscape vistas and formal gardens that attract people are also assigned further significance as markers of new divisions among social housing residents. We suggest that in order to realise the much-prophesised health and wellbeing benefits of urban ES in an equitable manner, a science-led approach to designing and assessing potential ES should be accompanied by a context-sensitive assessment of community needs and liveability aspects

On the Inverse Problem of Binocular 3D Motion Perception

It is shown that existing processing schemes of 3D motion perception such as interocular velocity difference, changing disparity over time, as well as joint encoding of motion and disparity, do not offer a general solution to the inverse optics problem of local binocular 3D motion. Instead we suggest that local velocity constraints in combination with binocular disparity and other depth cues provide a more flexible framework for the solution of the inverse problem. In the context of the aperture problem we derive predictions from two plausible default strategies: (1) the vector normal prefers slow motion in 3D whereas (2) the cyclopean average is based on slow motion in 2D. Predicting perceived motion directions for ambiguous line motion provides an opportunity to distinguish between these strategies of 3D motion processing. Our theoretical results suggest that velocity constraints and disparity from feature tracking are needed to solve the inverse problem of 3D motion perception. It seems plausible that motion and disparity input is processed in parallel and integrated late in the visual processing hierarchy

Ternary Fission of {sup 249}Cf(n,f) and {sup 250}Cf(SF)

During the last years, several Cm and Cf isotopes have been studied by our research group in the frame of a systematic investigation of gas emission characteristics in ternary fission. Here we report on new results on the energy distribution and the emission probability of {sup 3}H, {sup 4}He and {sup 6}He particles emitted in the spontaneous ternary fission of {sup 250}Cf (E{sub exc} = 0 MeV) and in the neutron induced ternary fission of {sup 249}Cf (E{sub exc} = 6.625 MeV). Both measurements were performed using suited and well-calibrated ΔE-E telescope detectors, at the IRMM (Geel, Belgium) for the spontaneous fission and at the very intense neutron beam PF1b at the Institute Laue-Langevin (Grenoble, France) for the neutron induced fission measurement. In this way, the existing database can be enlarged with new results for Z=98 isotopes, which is important for the systematic investigation. Moreover, the investigation of the 'isotope couple' {sup 249}Cf(n,f) - {sup 250}Cf(SF), together with corresponding data for other isotopes, will yield valuable information on the influence of the excitation energy on the particle emission probabilities