In this paper, we present a greedy subspace method for the acoustic echoes labeling problem, which occurs in applications such as source localization and room geometry estimation. The orthogonal projection into the null space of the microphones position matrix is used to filter and sort all possible combinations of echoes. A greedy strategy, based on the rank constraint of Euclidean distance matrices (EDMs), is used on the sorted subset of echo combinations to extract the feasible combinations. Numerical simulations using room impulse responses (RIRs) from shoe-box shaped rooms show that the method provides improvements in terms of computational complexity and the number of required measurements with respect to a recently published graph-based method.@en

Reverberation is well-known to have a detrimental impact on many localization methods for audio sources. We address this problem by imposing a model for the early reflections as well as a model for the audio source itself. Using these models, we propose two iterative localization methods that estimate the direction-of-arrival (DOA) of both the direct path of the audio source and the early reflections. In these methods, the contribution of the early reflections is essentially subtracted from the signal observations before localization of the direct path component, which may reduce the estimation bias. Our simulation results show that we can estimate the DOA of the desired signal more accurately with this procedure compared to state-of-the-art estimator in both synthetic and real data experiments with reverberation.@en

Knowledge on how a number of loudspeakers are positioned relative to a listening position can be used to enhance the listening experience. Usually, these loudspeaker positions are estimated using calibration signals, either audible or psycho-acoustically hidden inside the desired audio signal. In this paper, we propose to use the desired audio signal instead. Specifically, we treat the case of estimating the distance between two loudspeakers playing back a stereo music or speech signal. In this connection, we develop a real-time maximum likelihood estimator and demonstrate that it has a variance in the millimetre range in a real environment for even a modest sampling frequency.

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This paper focuses on the numerical modelling of SentryGlas-laminated reinforced glass beams. In these beams, which have been experimentally investigated in preceding research, a stainless steel reinforcement section is laminated at the inner recessed edge of a triple-layer glass beam by means of SentryGlas (SG) interlayer sheets. The current contribution numerically investigates the effect of the SG-interlayer shear stiffness on the overall structural response of the beams. This is done by means of a 3D finite element model in which the individual glass layers, the SG-interlayers and the reinforcement are incorporated. In the model, the glass parts are allowed to crack, but all other parts are assumed linear elastic throughout the analyses. By changing the shear modulus of the SG-interlayer in multiple analyses, its contribution to the overall structural performance of the beams - especially at the post-breakage stage - is investigated. From the results of the analyses it is observed that the residual load-bearing capacity, i.e. the load-bearing capacity after glass fracture, increases with an increasing shear modulus of the SG-interlayer. Furthermore, the load-displacement response from the numerical model is predicting experimental observations very well. However, the crack pattern resulting from the numerical model is not matching the experimental observations. Further studies are thus needed to fully understand the mechanisms involved in the structural behaviour of SGlaminated reinforced glass beams.

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