| Summary: | 碩士 === 國立臺灣海洋大學 === 系統工程暨造船學系 === 99 === Most nowadays city has high density population living in confined space. Inevitably, diverse kinds of noise exit in our living environment. Among which, the compound noise generated from complicated complex ground transportation system has seriously affected the quality of living environment and working performance. The aim of this thesis is mainly to develop the separation technique of the compound noise sources from the two more ground transportation systems. At the first step in the study, various sound collectors or accumulators are used to collect directionally the sound from various transportation system at a receiving rite, then the compound sound separation method is developed on the basis of the energy ratios amongst the directionally collected sounds each other. By the sound focussing effect consideration, a high performance sound collector has developed. This sound collector can exaggerate the directional sound level more than 10dB(A), comparing with the sound level measured by the collector deviated the sound source direction by an amount of no less than . Also, the collected sound field in the designed high performance sound collector has simulated by using the software package Raynoise. To validate the correctness of the established sound separation technique and to compare the sound collection effects with respect to the steel sound collection disk, the steel sound barrel, the plastic sound barrel and the high performance sound collector, the experimental measurement are carried out in an anechoic chamber and outdoors respectively. It shows that the accuracy of the compound noise separation by working the high performance sound collectors in the test with an error range between 0.2dB~0.8dB, the collected sound level can exaggerate 13dB~18dB, the available angle of collectors need for noise separation is .
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