Helmholtz resonators are commonly used for tuning of acoustic systems such as industrial processes, vehicle exhaust, engine intake manifold systems and more. Past efforts resulted in limited tuning capability and significant mechanical complexity. The work presented here considers a system that modifies the acoustic response of a system continuously, online, allowing optimum performance over a ...

In this work, a rigorous and practical design method for room acoustics is proposed. The ability to control acoustic characteristics has a wide range of applications, such as a car interior with controlled engine noise, barrier structures to suppress industrial and traffic noise, and design of concert halls and recording studios. The approach used in this work is based on installing rectangular...

The field of underwater acoustic networking is growing rapidly thanks to the key role it plays in many military and commercial applications. Among these are disaster prevention, tactical surveillance, offshore exploration, pollution monitoring and oceanographic data collection. The underwater acoustic propagation channel presents formidable challenges, including slow propagation of acoustic wav...

The acoustic design of auditoria involves the specification of the room geometry and boundary properties, and any additional acoustic elements such as reflectors or diffusers, to usefully direct sound to produce a desired subjective experience, quantified by measurable acoustic parameters. This design must take into account the reflection of sound within the stage area, the early reflections fr...

Objectives: The present study aims to compare acoustic voice parameters in patients with vocal cord nodules, polyps, and normal subjects.  Methods: In this cross-sectional case-control study, the participants were selected by convenience sampling, including 30 patients with vocal polyps group, 38 patients with vocal nodules for the second group, and 42 participants without voice pathologies a...

Broadening our understanding of the components and processes of speech sensorimotor learning is crucial to furthering methods of speech neurorehabilitation. Recent research in limb sensorimotor control has used virtual environments to study learning in novel sensorimotor working spaces. Comparable experimental paradigms have yet to be undertaken to study speech learning. We present acoustic and...

In this paper, a new type of multi-variable compensation control method for the wind energy conversion systems (WECS) is presented. Based on wind energy conversion systems, combining artificial neural network (ANN) control and PID, a new type of PID NN intelligent controller for steady state torque of the wind generator is designed, by which the steady state torque output is regulated to track ...

Acoustic lining assemblies with millions of high-density array holes are key structures for high-performance and low-noise aero-engines. However, the material specificity, variable curvature shape structure, high-order number holes, small-sized hole spacing acoustic pose great challenges to hole-making technology. In this paper, in view machining requirements a matrix unit design method batch m...

There are currently no known acoustic parameters by which stuttering children can be appraised in order to predict the further course of their speech disfluency. The present study investigates the usefulness of a computer-based speech analysis of fluent utterances. Correlations between acoustic variables, severity, and course of stuttering were sought in a prospective longitudinal study. This a...