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High rates of oil consumption and obesity in the US have become important socioeconomic concerns. While these concerns may seem unrelated at first, growing obesity rates in the US increase fuel consumption by adding passenger weight to vehicles. This paper estimates the additional amount of fuel (i.e., gasoline) consumed annually by noncommercial passenger highway vehicles in the US due to passenger overweight and obesity. The mathematical model presented in this paper estimates that as many as one billion additional gallons of gasoline are consumed each year due to overweight and obesity in the US, accounting for up to 0.8% of the fuel consumed by these vehicles annually. This additional fuel consumption causes carbon dioxide emissions of up to 20 billion pounds or more, accounting for up to 0.5% of the annual carbon dioxide emissions in the transportation sector.  相似文献   
603.
In this two-part paper, a topological analysis of powertrains for refuse-collecting vehicles (RCVs) based on the simulation of different architectures (internal combustion engine, hybrid electric, and hybrid hydraulic) on real routes is proposed. In this first part, a characterization of a standard route is performed, analyzing the average power consumption and the most frequent working points of an internal combustion engine (ICE) in real routes. This information is used to define alternative powertrain architectures. A hybrid hydraulic powertrain architecture is proposed and modelled. The proposed powertrain model is executed using two different control algorithms, with and without predictive strategies, with data obtained from real routes. A calculation engine (an algorithm which runs the vehicle models on real routes), is presented and used for simulations. This calculation engine has been specifically designed to analyze if the different alternative powertrain delivers the same performance of the original ICE. Finally, the overall performance of the different architectures and control strategies are summarized into a fuel and energy consumption table, which will be used in the second part of this paper to compare with the different architectures based on hybrid electric powertrain. The overall performance of the different architectures indicates that the use of a hybrid hydraulic powertrain with simple control laws can reduce the fuel consumption up to a 14 %.  相似文献   
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Experimental research results of surface damage accumulation in rail steel under rolling with slippage are presented. Hertz contact for two rollers made of rail and wheel steels was realized in the test. The influence of loading regime upon wear of rail is considered. The estimation of characteristics of surface fracture resistance for rail steel is made. The method to predict the life of rail steel under given conditions of regular loading is proposed.  相似文献   
606.
Concern for reduction in air‐borne lead emission from passenger cars is focussed on both the legislative and practical steps in reducing lead in gasoline. The historical trends and projections to 1990 of present U.S. and U.K. policies are examined in terms of a baseline passenger car lead emission rate, g.km‐1. It is likely that should the U.K. adopt a lead‐free petrol the decrease in lead emissions will only partially parallel the present U.S. experience from a start‐up date typically post 1990. The U.S. gasoline pool philosophy has permitted lead levels in gasoline to remain high; a pitfall which the U.K./EEC should avoid.  相似文献   
607.
The paper questions why so little attention has been given to the primary control centre of a merchant ship, namely the bridge, when so many accidents at sea are caused by ‘human error’. The paper then suggests that there is a need for a policy which will draw the various threads of the problem together in a form suitable for international discussion and even legislation. The identified areas are those of training, bridge design, psychology and marine traffic discipline.  相似文献   
608.
提出了电流变流体作为润滑剂使用的新设想,研究了电流变流体粘度的可控特性,通过试验获得了电流变流体摩擦力随电场强度、悬浮颗粒浓度、油膜厚度等因素的变化规律,为深入研究电流变流体的润滑特性奠定了基础。  相似文献   
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