Vehicle survival patterns in China

来源 :Science China(Technological Sciences) | 被引量 : 0次 | 上传用户:zhipeng
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The vehicle survival pattern describes the process that the survival ratio of vehicles decreases with the growth of vehicle age. Vehicle average life span and vehicle scrappage intensity are the key features of vehicle survival patterns and are important for the projection of China’s vehicle scrappage and ownership. In this study, we modeled the vehicle survival patterns of nine classifications of vehicles in China by employing the Weibull distribution, and obtained the vehicle survival ratio functions. It is estimated that the average life spans of private passenger vehicles, government and business vehicles, non-operating buses, heavy duty, medium duty and light duty trucks are 14.5, 13.1, 11.5, 12.8, 10.1, and 8 years, respectively. The scrappage intensities of these vehicles are similar. Average life spans of taxis, transit buses and non-transit operating buses are 5, 9, and 5.5 years with the pattern of mandatory scrappage. Vehicle scrappages in China are mainly regulated by the upper limits of vehicle distances traveled specified by the compulsory scrappage standards. The vehicle survival pattern describes the process that the survival ratio and the important for the projection of China’s vehicle scrappage and ownership. In this study, we modeled the vehicle survival patterns of nine classifications of vehicles in China by employing the Weibull distribution, and obtained the vehicle survival ratio functions. It is estimated that the average life spans of private passenger vehicles, government and business vehicles, non Average operating spans of taxis, transit buses and non- transit operating buses are 5, 9, and 5.5 years with the pattern of mandatory scrappage. Vehicle scrappages in China are mainly regulated by the u pper limits of vehicle distance traveled specified by the compulsory scrappage standards.
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