IWOCE RC PBC 2019

 
Welcome to International Workshop on Open Component Ecosystems 

Noise  



Noise is unwanted sound judged to be unpleasant, loud or disruptive to hearing. From a physics standpoint, noise is indistinguishable from sound, as both are vibrations through a medium, such as air or water. The difference arises when the brain receives and perceives a sound.

In audio engineering, noise can refer to the unwanted residual electronic noise signal that gives rise to acoustic noise heard as a hiss. This signal noise is commonly measured using A-weighting or ITU-R 468 weighting.
Sound is measured based on the amplitude and frequency of a sound wave. Amplitude measures how forceful the wave is. The energy in a sound wave is measured in decibels (dB), the measure of loudness, or intensity of a sound; this measurement describes the amplitude of a sound wave. Decibels (dB) are expressed in a logarithmic scale. On the other hand, pitch describes the frequency of a sound and is measured in hertz (Hz).
The main instrument to measure sounds in the air is the Sound Level Meter. There are many different varieties of instruments that are used to measure noise - Noise Dosimeters are often used in occupational environments, noise monitors are used to measure environmental noise and noise pollution, and recently smartphone-based sound level meter applications (apps) are being used to crowdsource and map recreational and community noise.
A-weighting is applied to a sound spectrum to represent the sound that humans are capable of hearing at each frequency. Sound pressure is thus expressed in terms of dBA. 0 dBA is the softest level that a person can hear. Normal speaking voices are around 65 dBA. A rock concert can be about 120 dBA.
In audio, recording, and broadcast systems, audio noise refers to the residual low-level sound (four major types: hiss, rumble, crackle, and hum) that is heard in quiet periods of program. This variation from the expected pure sound or silence can be caused by the audio recording equipment, the instrument, or ambient noise in the recording room.
Environmental noise is the accumulation of all noise present in a specified environment. The principal sources of environmental noise are surface motor vehicles, aircraft, trains and industrial sources. These noise sources expose millions of people to noise pollution that creates not only annoyance, but also significant health consequences such as elevated incidence of hearing loss and cardiovascular disease. There are a variety of mitigation strategies and controls available to reduce sound levels including source intensity reduction, land-use planning strategies, noise barriers and sound baffles, time of day use regimens, vehicle operational controls and architectural acoustics design measures.
Certain geographic areas or specific occupations may be at a higher risk of being exposed to constantly high levels of noise; in order to prevent negative health outcomes, regulations may be set. Noise regulation includes statutes or guidelines relating to sound transmission established by national, state or provincial and municipal levels of government. Environmental noise is governed by laws and standards which set maximum recommended levels of noise for specific land uses, such as residential areas, areas of outstanding natural beauty, or schools. These standards usually specify measurement using a weighting filter, most often A-weighting.
The European Environment Agency regulates noise control and surveillance within the European Union. The Environmental Noise Directive was set to determine levels of noise exposure, increase public access to information regarding environmental noise, and reduce environmental noise. Additionally, in the European Union, underwater noise is a pollutant according to the Marine Strategy Framework Directive (MSFD). The MSFD requires EU Member States to achieve or maintain Good Environmental Status, meaning that the "introduction of energy, including underwater noise, is at levels that do not adversely affect the marine environment".

 

 

 

 

 

 
 
 

Member of IWOCE RC PBC 2019:



Professor

Roberto Di Cosmo


Definitions of different ecosystems


Research Proposal


Software Component Definition


History alternative energy


Enabling  technologies


Renewable energy vs non-renewable energy


Relatively new concepts for alternative energy


Research alternative energy


Disadvantages alternative energy



RC PBC
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