Author Topic: Noise Problems  (Read 3698 times)

ben9108

  • Guest
Noise Problems
« on: May 09, 2006, 07:23:28 PM »
Dear Sir or Madam

WOuld you mind to help me solving the following problems?

1.      Under what condition will sound power level be lower than sound pressure level?
2.      L10, Leq, Lmax ~ How are they related to noise fluctuation and annoyance to people
3.      Why L10 cannot be used to assess night-time traffic noise?
4.      What is the relationship between L10, Leq, Lmax, for the noise from traffic, industrial fans, and piling machine?
5.      How to the parameters L10, Leq, L90, Lmin, Lmax, L10 – L90 and Lmax – Lmin change with traffic noise in the day and night time? Which of these parameters can be closely correlated to annoyance of people?
6.      Why balconies can be a more effective noise mitigation than barriers/ enclosures?
7.      Why the important of length, gaps, and absorptive material on the noise barrier performance?
8.      What measures to reduce train and industrial noise?
9.      Why the significance of low frequency noise from train and industrial machines?
10.      How acoustic wave from human speech is generated, propagated and detected by human ear?
11.      Why shaking a metal plate with large hand movement cannot generate noise but scratching it with a screwdriver can radiate loud noise?
12.      Why rows of trees 5m high and 20m wide may not block or absorb the noise but may increase the noise instead?
13.      What are the dominant frequencies of the noise emanating from electric motor unit, light rail, and locomotive? If the train noise level is 55dB(A) and 85 dB(C), which is the major noise source?
14.      Why enclosure is needed in rail when there are crossovers of rails? Do you think the floating slab can reduce the noise near crossovers?
15.      Why absorptive barrier close to the rail and floating slab should be used to reduce train noise on the viaduet. Why the negative effects of these on the operation of the train?
16.      Can the acoustic wave from the source of sound power level of 0dB be sensed by human ear?
17.      Why the noise impact from construction in terms of L10, Lmax, Leq and the period and duration when compared with industrial and traffic noise?
18.      Why barrier or enclosure may not be effective to reduce construction noise by evaluating the major noise sources?
19.      Why road resurfacing and barriers cannot reduce traffic noise near road junctions?
20.      Why Low frequency noise impact can be higher than high frequency noise impact?


Cheers

skip

  • Guest
Re: Noise Problems
« Reply #1 on: August 26, 2006, 05:26:56 PM »
This Forum was not intended t answer these types of questions in such depth. You may want to check with a company such as Eilar Associates an Engineering Firm that does in depth accoustical anyualysis. Try eilarassociates.com