| المستخلص: |
The traffic noise of public transportation vehicle makes up part of general environment problem hich inflicts serious damage to the health of human beings. Therefore, the control of traffic noise has become a matter of major concern for communities trying to maintain a satisfactory environment in which to live and work. To ensure a high quality environment, methods for prediction of the noise emission of public transportation vehicles are necessary tools. This paper is based on data of Department of Public Transportation & Petroleum of Khartoum town in 2009, and fieldwork in June 2009, and is confined to Mini Buses with passengers' capacity of 5- 25 persons. It applied Josse's mathematical model for noise level prediction to verify the objective of this paper which is to examine the contribution of Mini Buses into noise pollution in urban Khartoum town. Results depict that noise pollution ranges between 86.08 to 58.5 decibels with a mean value of 72.15 decibels to position urban Khartoum town in busy traffic category and to exceed the 45 dB recommended by Word Health Organization as fixed safe noise level for a city. The coefficient of variation equals 7.89% and the standard deviation is 5.80 decibels indicating to wide discrepancies of the distribution of noise pollution around the mean. Central stations of urban Khartoum town come first on ranking by level of noise pollution. Road width and number of journeys per Mini Buses partially determined levels of noise pollution where the value of the correlation coefficient is 0.48, indicating to contribution by 48% of noise pollution by these two factors. The value of the coefficient of multiple correlation is 0.69 showing somehow positive strong correlation between noise pollu¬tion levels and road width and number of journeys per Mini Buses. Differences on noise levels exist within axes, between nodes, edges (arcs) and end nodes, branches and circuits of the transportation network and the analysis of variance at 0.05 significance level confirmed that. However, the paper proposed a plan to curb noise levels caused by Mini Buses in urban Khartoum town.
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