Development of a soundscape simulator tool

This paper discusses the development of an interactive soundscape simulator, enabling users to manipulate a series of parameters to investigate if there is group correlation between factors such as source selection, positioning and level. The basis of the simulator stems from fieldwork and recordings carried out in London and Manchester. Through the use of an enhanced version of soundwalking, respondents are led on a walk around an urban space focusing on the soundscape, whilst answering questions in a semi-structured interview. The data collected is then used to inform the ecological validity of the simulator. The laboratory based tests use simulations based on spaces recorded in a series of urban locations, as well as an ‘idealised’ soundscape simulation, featuring data from all recorded locations. The sound sources used are based on user highlighted selections from all locations, based on preferences extracted from soundwalk field data. Preliminary results show the simulator is effective in obtaining numerical data based on subjective choices as well as, effective qualitative data which provides an insight into the reasoning behind the respondents choices. This work forms part of the Positive Soundscape Project

Entropic lattice Boltzmann methods

We present a general methodology for constructing lattice Boltzmann models of hydrodynamics with certain desired features of statistical physics and kinetic theory. We show how a methodology of linear programming theory, known as Fourier-Motzkin elimination, provides an important tool for visualizing the state space of lattice Boltzmann algorithms that conserve a given set of moments of the distribution function. We show how such models can be endowed with a Lyapunov functional, analogous to Boltzmann's H, resulting in unconditional numerical stability. Using the Chapman-Enskog analysis and numerical simulation, we demonstrate that such entropically stabilized lattice Boltzmann algorithms, while fully explicit and perfectly conservative, may achieve remarkably low values for transport coefficients, such as viscosity. Indeed, the lowest such attainable values are limited only by considerations of accuracy, rather than stability. The method thus holds promise for high-Reynolds number simulations of the Navier-Stokes equations.Comment: 54 pages, 16 figures. Proc. R. Soc. London A (in press

The effects of expectation on the perception of soundscapes

This thesis discusses how expectation is a contributory factor in the perception ofsoundscapes. "Soundscape" is a term attributed to R.Murray Schafer to define the acousticenvironment, a recent ISO workgroup has proposed a formal definition as the "perception andunderstanding of an acoustic environment, in context, by the individual, or by a society" Assuch there is a move away from traditional acoustic methods of understanding environmentalsound towards a more holistic, and interdisciplinary, approach to the sound environment.Previous soundscape research has identified the importance of semantic meaning attributed tosoundscapes focusing on investigating linguistic and textual approaches of how peopledescribe the soundscape. This thesis aims to extend the concept of meaning to give an insightinto what particular soundscapes mean to people, and if this related to a predefinedexpectation based on context. This work expands Truax's notion of soundscape competence,and investigates how people perceive the soundscape. In particular how expectation of aparticular space impacts on the perception of that space. This in turn addresses the issue ofdefining a context for a space and understanding how the soundscape is of importance toperception of spaces.The research which forms this work uses a number of interdisciplinary methods, from thefields of acoustics, social science and psychology, with the aim of developing a newqualitative and quantitative methodology for soundscape research. The work consists ofqualitative fieldwork, and the development of a soundscape simulator in the laboratory.Through the use of an enhanced version of soundwalking, participants were asked questionsaimed to analyse their pre-determined environmental expectation and their actual experienceof a number of different spaces, and how this impacts on their perception and evaluation ofthe soundscape. The soundscape simulator was a tool by which participants could control anddesign their own soundscapes, whilst providing useful quantitative and qualitative data aboutchoices made in the design process. Soundscape expectation is shown to relate not only tocompetence in perceiving the components of the soundscape but also to attitudes towardssafety, social norms, accepted behaviour, visual aesthetics and control attributed to the space.Expectation based on competence forms the basis of place expectation or context, and relatesto the overall perception of the soundscape for each space. When one or more of these factorsconflict with a perceived place expectation, then perception of the soundscape becomes moreimportant and impacts on the perception of the space. This work concludes that the meaningof a soundscape and its perception is related to an individual's expectation of the context of aspace

The effects of expectation on the perception of soundscapes

This paper explores how expectations of a place and its soundscape can affect our perception of that soundscape. Previous soundscape research has included expectation as one possible element of the context in which soundscape evaluation takes place. This work aimed to focus on expectation and unpack it to improve understanding of its different components and how it works. A combination of soundwalks, interviews, focus groups and an interactive soundscape simulation were used in the investigation. A linked series of locations in Manchester and London were studied. It was found that participants’ perceptions of a soundscape, both real and simulated, were affected by expectation in several different ways. Participants expected certain types of sound to be present in a particular space. Participants distinguished between whether a sound was expected and whether it sounded pleasant. It was also possible to distinguish between the expectation of particular sound sources and the expectation of the soundscape as a whole. The latter was found to be driven significantly by prior experience of similar spaces and also by perceived loudness. Participants also had expectations about the type of activity they could undertake in a particular soundscape, the behaviour of other people as expressed in the soundscape, and the degree of control they might have over their own exposure to the sound. These findings suggest that expectations of a soundscape are based on prior experience in a way which is consistent with Truax’s notion of soundscape competence. The results have been used to produce a new model for soundscape expectation which is expressed as a flowchart

The positive soundscape project : a synthesis of results from many disciplines

This paper takes an overall view of ongoing findings from the Positive Soundscape Project, a large inter-disciplinary soundscapes study which is nearing completion. Qualitative fieldwork (soundwalks and focus groups) and lab-based listening tests have revealed that two key dimensions of the emotional response are calmness and vibrancy. In the lab these factors explain nearly 80% of the variance in listener response. Physiological validation is being sought using fMRI measurements, and these have so far shown significant differences in the response of the brain to affective and neutral soundscapes. A conceptual framework which links the key soundscape components and which could be used for future design is outlined. Metrics are suggested for some perceptual scales and possibilities for soundscape synthesis for design and user engagement are discussed, as are the applications of the results to future research and environmental noise policy

Soundscape reproduction and synthesis

The aims of this work were to investigate (i) whether soundscape perceptual dimensions are correctly reproduced by ambisonic loudspeaker playback, (ii) whether soundscape dimensional analysis is robust to changes of location and from the field to laboratory playback, and (iii) whether a simple soundscape synthesis can be used to interactively design a soundscape. The first two aims were addressed by an experiment which attempted to repeat the dimensional analysis made by Kang (Kang, J. (2007), Urban Sound Environment. London: Taylor and Francis). Kang used semantic differential scales to conduct an in-situ survey of two urban soundscapes in Sheffield, UK. He used factor analysis to derive four perceptual dimensions from the responses. The present work repeated this approach, but the fifteen participants were judging ambisonic recordings of four soundscapes in Manchester, UK. The present work found very similar dimensions to Kang but with more variance explained: relaxation/calmness (41%), dynamics/vibrancy (10%), communication (7%) and spatiality (7%). The dimensions from the two studies load onto the semantic scales in a similar way. These results indicate that an ambisonic reproduction of a soundscape gives similar results to field experiments, though with more variance explained. They also show that dimensional analysis of soundscape response is robust enough to produce similar results for different locations in different cities. To investigate the third aim, the ambisonic reproduction was extended to a system which allowed independent interactive control of sixteen foreground sounds set in an ambisonic background soundscape. Eight participants were able to use this system to successfully design a soundscape that expressed their intentions. It was found that the designed soundscapes seemed to be based more on participant expectation of typical urban soundscapes than on their preference for individual sounds. These results suggest that a more sophisticated soundscape synthesiser might be suitable for real design problems

The pneumococcal divisome: dynamic control of streptococcus pneumoniae cell division

Cell division in Streptococcus pneumoniae (pneumococcus) is performed and regulated by a protein complex consisting of at least 14 different protein elements; known as the divisome. Recent findings have advanced our understanding of the molecular events surrounding this process and have provided new understanding of the mechanisms that occur during the division of pneumococcus. This review will provide an overview of the key protein complexes and how they are involved in cell division. We will discuss the interaction of proteins in the divisome complex that underpin the control mechanisms for cell division and cell wall synthesis and remodelling that are required in S. pneumoniae, including the involvement of virulence factors and capsular polysaccharides

'Choosing shoes': a preliminary study into the challenges facing clinicians in assessing footwear for rheumatoid patients

Background: Footwear has been accepted as a therapeutic intervention for the foot affected by rheumatoid arthritis (RA). Evidence relating to the objective assessment of footwear in patients with RA is limited. The aims of this study were to identify current footwear styles, footwear characteristics, and factors that influence footwear choice experienced by patients with RA. Methods: Eighty patients with RA were recruited from rheumatology clinics during the summer months. Clinical characteristics, global function, and foot impairment and disability measures were recorded. Current footwear, footwear characteristics and the factors associated with choice of footwear were identified. Suitability of footwear was recorded using pre-determined criteria for assessing footwear type, based on a previous study of foot pain. Results: The patients had longstanding RA with moderate-to severe disability and impairment. The foot and ankle assessment demonstrated a low-arch profile with both forefoot and rearfoot structural deformities. Over 50% of shoes worn by patients were opentype footwear. More than 70% of patients’ footwear was defined as being poor. Poor footwear characteristics such as heel rigidity and sole hardness were observed. Patients reported comfort (17%) and fit (14%) as important factors in choosing their own footwear. Only five percent (5%) of patients wore therapeutic footwear. Conclusions: The majority of patients with RA wear footwear that has been previously described as poor. Future work needs to aim to define and justify the specific features of footwear that may be of benefit to foot health for people with RA

Development and testing of Indoor Soundscape Questionnaire for evaluating contextual experience in public spaces

An Indoor Soundscape Questionnaire aiming at the evaluation of indoor public sound environments was designed, statistically tested and presented. It was established through initial pilot studies and three main factors under contextual experience variable are established as (1) psychological factors, (2) space usage factors and (3) demographical factors. In addition to the questions on demographical and space usage factors, detailed questions on psychological factors are designed and statistically tested for expectation, perception and reaction categories of the psychological factor. The questionnaire was applied as part of a case study in enclosed library foyer environments to a group of 270 participants through non-experimental survey data sampling. The reliability and validity scores of the Indoor Soundscape Questionnaire were statistically tested and confirmed. Furthermore, statistical tests were used to derive relationships between contextual experience variables of psychological, space usage and demographical factors. Chi-square test of goodness-of-fit results showed statistical significances of demographical and space usage factors with the psychological factors