The modeling of diffuse boundaries in the 2-D digital waveguide mesh

The digital waveguide mesh can be used to simulate the propagation of sound waves in an acoustic system. The accurate simulation of the acoustic characteristics of boundaries within such a system is an important part of the model. One significant property of an acoustic boundary is its diffusivity. Previous approaches to simulating diffuse boundaries in a digital waveguide mesh are effective but exhibit limitations and have not been analyzed in detail. An improved technique is presented here that simulates diffusion at boundaries and offers a high degree of control and consistency. This technique works by rotating wavefronts as they pass through a special diffusing layer adjacent to the boundary. The waves are rotated randomly according to a chosen probability function and the model is lossless. This diffusion model is analyzed in detail, and its diffusivity is quantified in the form of frequency dependent diffusion coefficients. The approach used to measuring boundary diffusion is described here in detail for the 2-D digital waveguide mesh and can readily be extended for the 3-D case

D-touch: A Consumer-Grade Tangible Interface Module and Musical Applications

We define a class of tangible media applications that can be implemented on consumer-grade personal computers. These applications interpret user manipulation of physical objects in a restricted space and produce unlocalized outputs. We propose a generic approach to the implementation of such interfaces using flexible fiducial markers, which identify objects to a robust and fast video-processing algorithm, so they can be recognized and tracked in real time. We describe an implementation of the technology, then report two new, flexible music performance applications that demonstrate and validate it

Acoustic modeling using the digital waveguide mesh

The digital waveguide mesh has been an active area of music acoustics research for over ten years. Although founded in 1-D digital waveguide modeling, the principles on which it is based are not new to researchers grounded in numerical simulation, FDTD methods, electromagnetic simulation, etc. This article has attempted to provide a considerable review of how the DWM has been applied to acoustic modeling and sound synthesis problems, including new 2-D object synthesis and an overview of recent research activities in articulatory vocal tract modeling, RIR synthesis, and reverberation simulation. The extensive, although not by any means exhaustive, list of references indicates that though the DWM may have parallels in other disciplines, it still offers something new in the field of acoustic simulation and sound synth

Impulse Response Estimation for the Auralisation of Vehicle Engine Sounds Using Dual Channel FFT Analysis

A method is presented to estimate the impulse response of a filter that describes the transformation in sound that takes place between a close-mic recording of a vehicle engine and the sound of the same engine at another point in or near to the vehicle. The proposed method makes use of the Dual Channel FFT Analysis technique and does not require the use of loudspeakers, computer modelling or mechanical devices. Instead, a minimum of two microphones is required and the engine itself is used as the source of sound. This is potentially useful for virtual reality applications or in sound design for computer games, where users select their virtual position at points inside or outside the vehicle. A case study is described to examine the method in practice and the results are discussed. The described method can be readily extended for surround sound applications using spatial microphone array recording techniques

How members of the public account for the England Riots of summer 2011

The purpose of this study is to gain knowledge of how the general public viewed the England riots of 2011 in order to gain a fuller understanding of the riots and their impact on society. The study involved the thematic analysis of four semi-structured focus groups that were conducted with a total of eighteen participants from differing backgrounds. The analysis identified five themes: how participants draw on traditional theories of the crowd; the Police were deemed to be ‘damned if they do and damned if they don’t’; opportunism was used to account for looting; the media were viewed as aiding the spread of the riots but also as informative and as aiding the cleanup after the riots ended; and the riots were presented as being understandable, but in no way acceptable. This demonstrates how public understanding of the riots differs from the psychological literature. Practical recommendations are suggested including the need to give a platform to crowd psychologists

Assessing possible environmental causes behind the reduced colonisation of western rock lobster puerulus collectors by a wide suite of species. FRDC report : project 2008/085

Objectives 1) Begin monitoring the community composition of marine flora and fauna along the Western Australian coastline during this current poor settlement period. 2) Develop standard methodology for monitoring the spatial and temporal variability in the settlement of marine flora and fauna. 3) Determine what environmental parameters may be linked to the majority of variation in the floral and faunal communities colonizing puerulus collectors, focusing on those relating to puerulus settlement. 4) Identify indicator marine flora and fauna species for monitoring the influences of environmental change on Western Australian marine environment. 5) Detect any known or potential introduced marine pests within the Western Australian environment