Modeling a porous layer mounted on a vibrating structure using acoustic impedance is investigated in this paper. It is shown that the use of surface impedance usually measured with the impedance tube method can provide an inaccurate estimation of the acoustic pressure radiated by the covered structure. The paper focuses on the derivation of an impedance, denoted the “transfer impedance,” which ...

Given a collection {Z1, Z2, . . . , Zm} of n-sided polygons in the plane and a query polygon W we give algorithms to find all Zl such that W = f(Zl) with f an unknown similarity transformation in time independent of the size of the collection. If f is a known affine transformation, we show how to find all Zl such that W = f(Zl) in O(n+ log(m)) time. For a pair W,W ′ of polygons we can find all ...

Models for acoustic transducers, such as loudspeakers, mastoid bone-drivers, hearing-aid receivers, etc., are critical elements in many acoustic applications. Acoustic transducers employ two-port models to convert between acoustic and electromagnetic signals. This study analyzes a widely-used commercial hearing-aid receiver ED series, manufactured by Knowles Electronics, Inc. Electromagnetic tr...

We consider energy transfer from an elastic actuator to load, and show that the can be optimized by tuning Young's modulus of impedance matching host material.

This paper proposes a new index to determine the static voltage stability of the load buses in a power network for certain operating conditions and hence identifies load buses which are close to voltage collapse. The proposed index is formulated from the quadratic equation derived from a twobus network and is computed using the apparent power and the line impedance. The proposed index shows how...

When performing in-situ measurements of conducted emission, it is not always possible to use a LISN (line impedance stabilisation network). This is especially the case when testing large machines, where a LISN with a high current capacity is needed. In this paper some alternative test methods are proposed to measure conducted emission. The measurements are compared to the LISN measurement and e...