Int J Environ Res Public Health
August 2021
This paper presents the results of a study evaluating the human perception of the noise produced by four different small quadcopter unmanned aerial vehicles (UAVs). This study utilised measurements and recordings of the noise produced by the quadcopter UAVs in hover and in constant-speed flight at a fixed altitude. Measurements made using a ½″ microphone were used to calculate a range of different noise metrics for each noise event.
View Article and Find Full Text PDFThis paper investigates the learning effect of a developed coursework for an engineering acoustics course offered to fourth year and postgraduate engineering students at the University of Auckland, New Zealand. The coursework incorporated practical active-learning activities and was developed to help students gain understanding of complex concepts related to the room-acoustics measurement and analysis and also introduce students to some of the practical tasks that are typical of a practising acoustical engineer in New Zealand. The learning effect of the coursework was measured by comparing students' performance in two quizzes that were run before and after students worked on the coursework.
View Article and Find Full Text PDFJ Wound Ostomy Continence Nurs
August 2021
In anticipation of a major construction project in an urban New Zealand zoo, a study was initiated to assess the response to construction noise of selected animal species (elephant, giraffe, emu and alligator) previously observed to be sensitive to this kind of noise. The overall aim was to detect any signs of aversive responses to this noise to enable keepers to recognize these and take any necessary mitigating actions during the construction period. The experimental approach involved the creation of acoustic maps of each focal animal enclosure, a series of 90-min video recordings of the animals' behavior in response to ambient noise (control) and amplified broadcast of pre-recorded continuous and intermittent construction noise.
View Article and Find Full Text PDFAn existing theoretical model to predict the pressure levels on an aircraft's fuselage is improved by incorporating a more physically realistic method to predict fan tone radiation from the intake of an installed turbofan aero-engine. Such a model can be used as part of a method to assess cabin noise. Fan tone radiation from a turbofan intake is modelled using the exact solution for the radiated pressure from a spinning mode exiting a semi-infinite cylindrical duct immersed in a uniform flow.
View Article and Find Full Text PDFThis paper describes the extension of a wave and finite element (WFE) method to the prediction of noise transmission through, and radiation from, infinite panels. The WFE method starts with a conventional finite element model of a small segment of the panel. For a given frequency, the mass and stiffness matrices of the segment are used to form the structural dynamic stiffness matrix.
View Article and Find Full Text PDFA distributed source model to predict fan tone noise levels of an installed turbofan aero-engine is extended to include the refraction effects caused by the fuselage boundary layer. The model is a simple representation of an installed turbofan, where fan tones are represented in terms of spinning modes radiated from a semi-infinite circular duct, and the aircraft's fuselage is represented by an infinitely long, rigid cylinder. The distributed source is a disk, formed by integrating infinitesimal volume sources located on the intake duct termination.
View Article and Find Full Text PDFJ Acoust Soc Am
September 2015
The development of a distributed source model to predict fan tone noise levels of an installed turbofan aero-engine is reported. The key objective is to examine a canonical problem: how to predict the pressure field due to a distributed source located near an infinite, rigid cylinder. This canonical problem is a simple representation of an installed turbofan, where the distributed source is based on the pressure pattern generated by a spinning duct mode, and the rigid cylinder represents an aircraft fuselage.
View Article and Find Full Text PDFJ Wound Ostomy Continence Nurs
April 2015
This article is an executive summary of A Quick Reference Guide for Managing Fecal Incontinence (FI), which was published September 2013 by the WOCN Society's Continence Committee. The quick reference guide provides an overview of fecal incontinence and how it is commonly managed. The information has been compiled so that nurses can quickly access a wide array of information in a single resource to facilitate patient care and patient/staff education.
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