Feasibility Study of Airbag Concept Applicable to Motorcycles Without Sufficient Reaction Structure

Objectives: An airbag system for motorcycle applications was developed and marketed in 2006 followed by many research projects on the system. In the airbag system, the bag should be supported during the kinetic energy–absorbing period of a rider in a collision. The previously developed system employed a configuration in which motorcycle structures support the airbag, such as a gauge unit and/or a steering structure. The supporting structure functions to receive the reaction force to hold the airbag during a crash to properly absorb the rider's kinetic energy. However, the previous system requires a larger area for this reaction structure and is applicable only to the motorcycles that can provide that area. To overcome this limitation, we propose an airbag system employing another concept. In this concept, the airbag does not use its vehicle structures as a reaction structure but uses the structures of an opposing vehicle, such as doors and/or pillars of an opposing vehicle. In this project, we aim to verify the effectiveness of the proposed system when installed in a motorcycle that cannot provide a larger area for the reaction structure.

Methods: In the system with this concept, it is assumed that the occupant protection performance is largely affected depending on impact configurations. Accordingly, full-scale motorcycle-to-car crash tests using 125 cm³ scooter-type models with and without the proposed system were conducted in various impact configurations. The 7 impact configurations specified in ISO 13232 were selected as the test configurations. Injury variables and injury indices of head, neck, chest, and abdomen were evaluated with the motorcyclist dummy.

Results: Injury variables and indices obtained from the crash tests with the airbag were compared to those of the baseline tests. In 2 impact configurations, the airbags were supported by the side structures of the opposing vehicle and performed to reduce the injury variable of head and/or chest compared to that of the baseline test.

Conclusion: Through the crash tests, beneficial protection effects of the airbag system were confirmed in particular impact configurations. No significant risk for the occupant due to the airbag was observed in the conducted crash tests. It was concluded that the proposed airbag system has feasibility to reduce rider injury in a collision of a motorcycle without sufficient reaction structure.     

微穿孔板吸声结构设计参数研究进展

为推进健康城市防噪降噪工作,预防和减少噪声污染对人们健康产生的危害和不良影响,研究声学材料-微穿孔板吸声结构设计参数对降噪防噪的促进作用。首先,采用文献综述方法,以传统微穿孔板基本理论和基本特性为基础,根据国内外研究现状,按照改变板结构、微孔结构和空腔结构等设计参数进行分类;其次,分析不同改变方式对微穿孔板吸声性能的影响;最后,归纳总结可提升微穿孔板降噪功效的不同方法。研究结果表明:合理改变微穿孔板吸声结构设计参数是预防和改善噪声污染的有效方法,研究结果可为健康城市防噪降噪工作提供参考依据及理论支撑。     

中国省域空间单元绿色治理效率测度及其空间格局特征

全文构建广义面板三阶段DEA模型,实证测度2008～2019年我国31个省域绿色治理效率,基于外部环境和投影分析探究绿色治理的改进方向;利用空间自相关模型,判断省域绿色治理效率的潜在关联;通过空间引力模型、社会网络分析法,明确各省域绿色治理效率的空间关联规模,形成网络拓扑结构下的绿色治理效率社会网络.研究发现,中国省域...     

中国对外贸易的环境影响综合效应分析

在全面提高开放型经济水平的背景下,需要深入分析对外贸易规模、外贸经济布局对环境影响的综合效应,全面探索对外贸易的环境效应规律。理论分析主要考察了对外贸易发展对环境影响综合效应的作用机制,在污染的需求和供给函数基础上,将环境因素分别引入对外贸易的生产者函数、消费者函数、政府税收函数,构建对外贸易环境总效应实证模型,模型分析表明,对外贸易对环境影响的规模效应体现为环境污染在不同禀赋和收入水平国家间转移;对外贸易对环境影响的结构效应体现为出口产品结构的改变,但是由于不同的比较优势,该结构效应在各经济体间的正负影响各不相同;资本积累会带来更多的污染,技术进步则会降低污染水平,二者相互作用究竟产生正面还是负面的影响效果,关键看资本积累和技术进步是否带来污染密集型产品的生产。同时基于我国29个省(市)的动态面板数据,实证检验了我国经济总量、外贸规模、外贸经济布局对环境影响的综合效应。研究表明,经济增长导致的收入效应和规模效应使污染物排放量呈现先下降然后增长的变化,而外商投资在短期内会增加环境污染,但从长期来看,正的技术效应使污染排放量呈现逐渐降低的趋势,同时受到产业结构的约束,外贸经济布局的产品效应及结构效应呈现显著的负效应。我国对外贸易对环境影响负效应产生的现实基础来源于我国的外贸结构与模式等特征的国情基础,改善我国的外贸对环境影响的负效应需要通过继续深化外贸体制改革,转变外贸增长方式,完善环境经济政策,加强国际多边合作等综合手段来实现。     

中国省域能源强度趋同俱乐部存在性及影响因素分析

中国疆域广大,各地的资源禀赋、能源消耗状况以及经济增长方式存在有着很大的差异,这也导致各地区之间的能源强度水平有着显著的区别。中国各地区之间这种差异很大的能源强度水平是否存在类似经济增长趋同的性质,是否也会呈现出一定的俱乐部趋同现象,这对于探索区域能源差异化政策具有重要意义。以中国30个省市区2000~2014年与能源强度水平有关的数据作为分析的基础,首先从理论上阐述了中国能源强度水平的空间相关性,然后构建实证模型,对2000~2014年中国整体能源强度以及分省域能源强度趋同俱乐部的存在性展开实证研究与检验;对第二产业产值(SEN)、固定资产投资(TZ)、RD经费支出(RD)、外商直接投资(FDI)等对各省域能源强度趋同的作用效果做出预估。结果表明我国各省市间能源强度的差距逐步减小,且存在空间上的省域能源强度趋同俱乐部现象;各经济变量对各区域能源强度作用效果各不相同;所以,在制定与能源相关的政策时,要考虑不同地域的客观差别,有针对性实施差异化能源政策。     

耕地资源变化的空间计量及其驱动力分析——以江苏省为例

采用1998~2008年江苏省13个地级市的耕地数据,分析了近10 a来耕地数量变化的基本过程及空间差异。然后运用Moran I指数验证了耕地资源分布空间相关性的存在,并利用空间计量模型研究了江苏省耕地数量变化的驱动机制。结果表明：（1）1998~2008年,江苏省耕地面积净减少2969×104 hm2,平均每年减少270×104 hm2。耕地数量变化存在明显的空间差异,无锡、苏州、常州、南京和镇江5个地区耕地资源减少最为严重;（2）全省耕地资源空间分布存在明显的空间相关性,1998~2008年,耕地面积Moran I值由0400 3增加至0452 4,呈逐步增强的趋势;（3）人口、经济增长和粮经作物比是江苏省耕地数量变化的主要驱动因子,其弹性系数分别为-0803、-0070、0069;（4）相邻地区各因素的空间扩散效应对耕地数量变化存在显著的影响,其弹性系数为0779,因此,未来在制定耕地保护政策,应考虑区域耕地资源分布的空间相关性,推进跨区域耕地保护机制的形成,建立一体化的区域耕地保护政策。     

环境质量对中国城镇居民健康支出的影响

将工业二氧化硫排放量作为环境质量的代理变量,对中国各个地区分别建立面板数据模型,研究中国城镇居民医疗保健支出与居民收入和环境质量之间的长期均衡关系,并基于面板误差纠正模型来分析医疗支出对各影响因素的短期调节效应。实证结果表明,环境质量对医疗支出影响的长期弹性在我国东部、中部和西部各地区均为正值,说明环境污染的加剧导致人们健康状况的恶化,从而促进了医疗支出的增长。因此,做好环境保护工作应该具有长久坚持的意义。但是,从短期来看,环境质量对医疗支出的影响却为负值,这一结果解释了当前有些地区和部门在短期内会以牺牲环境为代价来换取经济的暂时发展,由此更加突显了做好环境保护工作的艰巨性与紧迫性。另一方面,居民收入对医疗保健支出影响的长期弹性和短期弹性均大于1,表明提高城镇居民收入水平对于改善居民健康状况具有显著作用,由此说明我国当前实施的工资增长机制、提高医疗补助政策具有其针对性和适宜性。     

A Multi‐Scale Analysis of Low‐Rise Apartment Water Demand through Integration of Water Consumption,Land Use,and Demographic Data

Over the past decades, multi‐unit housing developments have been vastly expanded across urban areas due to the population growth. To properly supply water to this growing sector, it is essential to understand the determinants of its water use. However, this task has largely remained unexplored through the empirical study of water demand mainly due to the scarcity of data in this sector. This study integrated apartment water consumption, property characteristics, weather, water pricing, and census microdata to overcome this issue. Using a rich source of GIS‐based urban databases in Auckland, New Zealand, the study developed a large dataset containing the information of 18,000 low‐rise apartments to evaluate the determinants of water use both in the household scale and aggregated scale. The household‐scale demand analysis helped to assess the heterogeneity in responses to the demand drivers specifically water price across different consumer groups, whereas the aggregated analysis revealed the determinants behind the spatial variation in water demand at the census area unit level. Through applying panel data models, the study revealed the household size as the most important determinant of apartment water use in Auckland, where other socioeconomic factors, building features, and water pricing were not significant determinants. This knowledge of determinants of water demand can help water planners to better manage water demand in the compact urban environments.