Noise pollution is a major factor of environmental complaints in many cities, which has significant impacts on human health. As a dominating source of environmental noise, the impact of road traffic noise is increasing. Residents living in high-rise buildings along the main road are severely affected by traffic noise. In order to assess the noise level of urban area along the main road in Guangzhou, three buildings were selected to conduct traffic noise measurements, and the questionnaire about traffic noise impact on human being was completed. Through the questionnaire, around 70% of participants consider the traffic noise has negative effect, and about 60% of participants consider the noise has moderate or much higher impact on physical comfort. Around 65% of participants consider the noise had moderately or much higher impact on their psychological comfort. By analyzing the measured data, all of the measured noise levels in three buildings exceed the recommended limit of 55 dB (A) in the daytime and 45 dB (A) in the night for residence, and the exceeded value can be up to 16 dB (A). By comparing the fitting curve of noise level transfer function on each floor relative to the reference floor, the quadratic polynomial was selected to plot the transfer function rather than cubic polynomial.
The concept of security has been redefined since the 1990s. As one of the important factors threatening human security, global environmental change has become a new challenge to the national security and social development. The national security problems caused by global environmental change, on one hand, are closely related to the global environmental problems, and, on the other hand, are manifested in the conflicts of international affairs. The global environmental change severely challenges the future de... 相似文献
以区域电网应急抢修资源调度为例,分析了区域应急物流配送系统的特征,进行了无枢纽产能限制的多重枢纽指派模式的"Uncapacitated multi p-Hub"应急物流配送系统的建模及其两阶段启发式算法的设计,并以长三角区域电网应急抢修资源调度为例进行了算例研究,提出了该系统在实际应用中应当注意的重要问题。 相似文献