Diffraction Kernels for Interactive Sound Propagation in Dynamic Environments.

We present a novel method to generate plausible diffraction effects for interactive sound propagation in dynamic scenes. Our approach precomputes a diffraction kernel for each dynamic object in the scene and combines them with interactive ray tracing algorithms at runtime. A diffraction kernel encapsulates the sound interaction behavior of individual objects in the free field and we present a new source placement algorithm to significantly accelerate the precomputation.

Effects of virtual acoustics on dynamic auditory distance perception.

Sound propagation encompasses various acoustic phenomena including reverberation. Current virtual acoustic methods ranging from parametric filters to physically accurate solvers can simulate reverberation with varying degrees of fidelity. The effects of reverberant sounds generated using different propagation algorithms on acoustic distance perception are investigated.

SynCoPation: Interactive Synthesis-Coupled Sound Propagation.

Recent research in sound simulation has focused on either sound synthesis or sound propagation, and many standalone algorithms have been developed for each domain. We present a novel technique for coupling sound synthesis with sound propagation to automatically generate realistic aural content for virtual environments. Our approach can generate sounds from rigid-bodies based on the vibration modes and radiation coefficients represented by the single-point multipole expansion.

WAVE: Interactive Wave-based Sound Propagation for Virtual Environments.

We present an interactive wave-based sound propagation system that generates accurate, realistic sound in virtual environments for dynamic (moving) sources and listeners. We propose a novel algorithm to accurately solve the wave equation for dynamic sources and listeners using a combination of precomputation techniques and GPU-based runtime evaluation. Our system can handle large environments typically used in VR applications, compute spatial sound corresponding to listener's motion (including head tracking) and handle both omnidirectional and directional sources, all at interactive rates.

Dispersing Grafted Nanoparticle Assemblies into Polymer Melts through Flow Fields.

Flow-fields are typically used to intimately mix large μm-sized particles with polymer melts. Here we show, using rheology, X-ray scattering, and electron microscopy, that shear flows do not improve the spatial dispersion or ordering of spherical nanoparticles (NP) grafted with polymer chains over the ranges of flow fields realizable in our experiments in the melt state. In the absence of flow, grafted NPs robustly self-assemble into a variety of superstructures when they are added to a homopolymer matrix with the same chemistry as the NP grafts.