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111.
Tin-cheung Chan Kin-che Lam 《Transportation Research Part D: Transport and Environment》2008,13(5):334-339
We investigate how two non-acoustic factors, information bias and riding frequency, can affect the annoyance response of an urban population to noise created by a new railway line. The study shows that information bias is asymmetrical. Respondents receiving only information on positive measures taken by the authority to reduce noise emission are more tolerant of the noise impact, but those receiving only critical views tend to be more annoyed because they feel that not all measures to reduce noise have been employed. Additionally people who use the line frequently are more tolerant to the noise impact than those who do not. Information bias seems to have a temporary masking effect over riding frequency lasting for a few weeks after railway opening. This suggest that whilst free flow of information provided by the authority can help alleviate annoyance response, encouraging the people affected to make use of the new infrastructure may be useful to reduce public resistance and noise annoyance. 相似文献
112.
113.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(2):323-337
In this first part of a two-part article, a previously described and validated finite-element model of a racing-car tyre is developed further to yield detailed information on carcass deflections and contact pressure and shear stress distributions for a steady rolling, slipping, and cambered tyre. Variations in running conditions simulated include loads of 1500, 3000 and 4500 N, camber angles of 0° and ?3°, and longitudinal slips from 0% to?20%. Special attention is paid to heavy braking, in which context the aligning moment is of great interest. Results generated are in broad agreement with limited experimental results from the literature and they provide considerable insight into how the tyre deforms and how the contact stresses are distributed as functions of the running conditions. Generally, each rib of the tyre behaves differently from the others, especially when the wheel is cambered. The results form a basis for the development of a simpler physical tyre model, the purpose of which is to retain accuracy over the full operating range while demanding much less computational resource. The physical tyre model is the topic of the second part of the article. 相似文献
114.
海上平台中央空调系统噪声分析和降噪方案研究 总被引:1,自引:1,他引:0
文章通过惠州21—1B平台中央空调系统测试和改进实践,对该系统的噪声进行了分析,并提出了相应的降噪方案。 相似文献
115.
We modeled the propagation of traffic noise over the landscape and analyzed its impact on the structure and configuration of protected areas of the Twin Cities Metro Region, Minnesota. Using four noise thresholds, we found that at low and medium noise levels, 19% and 11% of the protected areas are within the road-effect zone. Using mean patch area and patch shape index, we measured the acoustic fragmentation of habitats. We found that at higher levels of noise patch shape index increased, while mean patch size decreased. The acoustic diversity of a patch is also found to be correlated with land cover type, patch area, and patch shape. 相似文献
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117.
对中、欧、加等国就汽车噪声的限值要求及试验方法作比较,并实测验证两种试验方法的差别。 相似文献
118.
冲击碾压技术在高速公路改建工程中的应用 总被引:1,自引:0,他引:1
冲击碾压技术已在我国新建和改扩建公路工程等项目上予以应用。它不仅能确保工程进度,而且能有效地防止路面出现反射裂缝,从而提高工程质量。该文结合高界高速公路改建工程,从冲击的速度、顺序、遍数,以及防水措施等方面介绍了冲击碾压技术的施工工艺。 相似文献
119.
沥青路面的压实是影响沥青路面使用年限的重要指标,该文分析了材料、外界温度、压实工艺和混合料的种类及性质等各方面因素对沥青路面压实的影响,其中又侧重于温度及外界环境因素影响的分析。 相似文献
120.
车体下部噪声的吸声降噪对策 总被引:1,自引:0,他引:1
降低高速列车产生的噪声,必须降低车体下部噪声。本文对用吸声板降低车体下部噪声的措施作了介绍,对吸声材料的性能进行了评价,对贴附在实际列车上的吸声板的最佳面积进行了阐述。 相似文献