Search for dissertations about: "active control of sound"
Showing result 1 - 5 of 22 swedish dissertations containing the words active control of sound.
-
1. Linear Quadratic Gaussian Controllers for Feedforward Active Noise Control : Pushing Performance and Moving Towards Adaptive Control
Abstract : Active noise control is a research area focused on using destructive interference of sound fields to attenuate undesired noise. Methods for active noise control are best suited for low frequency noise, as the complexity of the problem grows rapidly with frequency. READ MORE
-
2. Active Control of Propeller-Induced Noise in Aircraft : Algorithms & Methods
Abstract : In the last decade acoustic noise has become more and more regarded as a problem. In cars, boats, trains and aircraft, low-frequency noise reduces comfort. Lightweight materials and more powerful engines are used in high-speed vehicles, resulting in a general increase in interior noise levels. READ MORE
-
3. Estimation and Control of Resonant Systems with Stochastic Disturbances
Abstract : The presence of vibration is an important problem in many engineering applications. Various passive techniques have traditionally been used in order to reduce waves and vibrations, and their harmful effects. Passive techniques are, however, difficult to apply in the low frequency region. READ MORE
-
4. Active Noise Control of Enclosed Sound Fields Optimising the Performance
Abstract : Active noise control is the art of reducing a primary unwanted sound field by interference with an actively created secondary sound field. To achieve high reduction, it is crucial to obtain both temporal and spatial matching between the primary and the secondary sound fields. READ MORE
-
5. Active Junction Control and Piezoelectric Hybrid Damping for Improving the Acoustic Performance of Lightweight Structures
Abstract : Weight reduction is a key factor in lowering the fuel consumption and thereby the greenhouse emissions from vehicles. However, reducing the weight normally results in a deterioration of the acoustic performance. Thus, the purpose of this thesis is to investigate damping treatments for lightweight vehicle panels. READ MORE