In this paper, the classical triple-deck formalism is employed to investigate two instability problems in which an acoustic feedback loop plays an essential role. The first concerns a subsonic boundary layer over a flat plate on which two well-separated roughness elements are present. A spatially amplifying Tollmien-Schlichting (T-S) wave between the roughness elements is scattered by the downs...

A reciprocal measurement procedure to measure the acoustic feedback path in hearing aids is investigated. The advantage of the reciprocal measurement compared to the direct measurement is a significantly reduced sound pressure in the ear. The direct and reciprocal measurements are compared using measurements on a dummy head with adjustable ear canals, different earmolds, and variations in the o...

This paper investigates a novel multiple-history long short-term memory (MH-LSTM) RNN acoustic model to mitigate the robustness problem of noisy outputs in the form of mis-labeled data and/or mis-alignments. Conceptually, after an RNN is unfolded in time, the hidden units in each layer are re-arranged into ordered sub-layers with a master sub-layer on top and a set of auxiliary sub-layers below...

For many applications such as acoustic echo compensation, adaptive noise reduction or acoustic feedback control it is of great interest to simulate reproducibly a real, time variant room. One approach to describe the transient behavior of a room is the generation of a physical room model, e.g. [l]. To identify the variation of a room impulse response with time an alternative concept is presente...

Forced air cooling systems, such as an airconditioning system produce noise. For a pleasant living environment, this noise is undesirable. A way to suppress produced noise is reducing the sound in the duct where the air flows through afterwards. a his report handles the noise reduction in an active duct silencer by the use of a discrete feedback controller. Models of the involved processes are ...

Dual-system models of visual category learning posit the existence of an explicit, hypothesis-testing reflective system, as well as an implicit, procedural-based reflexive system. The reflective and reflexive learning systems are competitive and neurally dissociable. Relatively little is known about the role of these domain-general learning systems in speech category learning. Given the multidi...

Post-decision restructuring is the unconscious revision of what one saw and thought in the pre-decision stage as a result of outcome feedback. Professional auditors and auditing students participated in a post-decision restructuring (hindsight) experiment involving going concern judgments. Lack of feedback among professional participants invited more pronounced post-decision adjustments than ac...

Passengers communication inside a car can be improved by using a speech reinforcement system. This system picks up the speech of each passenger, amplifies it and plays it back into the cabin through the loudspeakers of the car. Due to the electro-acoustic coupling between loudspeakers and microphones, a closed-loop system is created. To avoid the risk of instability due to the acoustic feedback...

Speech technology has long been utilised to within computer-assisted tools for voice training. Such tools, providing real-time visual feedback of specific characteristics of the voice, complement traditional training methods. However, in order for such technology to be successful, specific aspects of voice training must be considered including the nature of voice perception, motor learning proc...