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41.
In this article, two kinematics-based observers are proposed to estimate the vehicle roll and pitch angles by using an inertial measurement unit. The observers are mathematically proven to be stable if the vehicle yaw rate is not zero. With a design variation of the observer gains, the estimated roll or pitch angle is shown to further asymptotically converge to the true value, eliminating possible errors caused by the biases of the acceleration signals. Simulation results show that accurate estimation of both pitch and roll angles can be achieved without the help of external sensors such as global positioning systems, either by using the accelerometer-based reference pitch or roll angle as the maneuver varies, or by using an observer with zero steady-state error property.  相似文献   
42.
Kalman inverse filtering is used to develop a methodology for real-time estimation of forces acting at the interface between tyre and road on large off-highway mining trucks. The system model formulated is capable of estimating the three components of tyre-force at each wheel of the truck using a practical set of measurements and inputs. Good tracking is obtained by the estimated tyre-forces when compared with those simulated by an ADAMS virtual-truck model. A sensitivity analysis determines the susceptibility of the tyre-force estimates to uncertainties in the truck's parameters.  相似文献   
43.
基于汽车启停系统的车载网络技术研究   总被引:1,自引:0,他引:1  
本论文介绍了汽车启停技术的应用背景、控制原理,并介绍了汽车车载网络的应用,结合具体车型分析了车载网络技术在汽车启停系统中的应用。  相似文献   
44.
本文介绍了C语言中一种新的协程编程模型,即利用Timer驱动有限状态机方式,有效地解决了传统C语言协程实现的兼容性和跨平台等问题,提供了C语言下并行编程除线程之外的另一种选择。  相似文献   
45.
城市多模式公交网络出行时间可靠性模型研究   总被引:1,自引:0,他引:1  
随着城市的发展,快速轨道交通和快速公交系统逐渐融入到常规公交系统中,构成了复杂的多模式公交网络,在此公交网络环境下乘客公交出行时间的稳定可靠程度直接影响到公交系统的服务性能,因此,本文以常规公交和地铁组成的典型多模式公交网络为研究对象,利用状态增广技术,建立了换乘约束条件下的出行时间可靠性模型,从而为评价和改善多模式公交网络服务性能提供决策支持。  相似文献   
46.
我国经修订的新的2010年船舶安全检查规则现已开始实施。本文简评新的船舶安检规则的特点,讨论其与98规则比较有哪些变化,并对该规则的一些存疑进行相关的研讨。  相似文献   
47.
This research applied the Green Flag Program to assess the benefits of reducing speed and fuel transfer for large merchant vessels (bulk and container) entering Kaohsiung Port. This study adopts an activity-based model to calculate fuel consumption and emissions, as well as setting up two scenarios, (1) decrease vessel speed to 12 knots 20 nm away from port; and (2) decrease vessel speed to 12 knots and transfer fuel 20 nm away from port, which based on the Green Flag Program in Long Beach, in the U.S. The findings are (1) In scenario one, the container and bulk vessels saw reductions in CO2 emissions of about 41% and 14%, respectively. In scenario two, container and bulk vessels had reductions of about 48% and 43% in SO2 emissions, respectively. (2) Large vessels are more environmentally friendly than small vessels. (3) Using the CATCH model to assess the effectiveness of the two scenarios, it was found that container vessels benefited from both reducing speed and fuel transfer, while bulk carriers only did so from the former.  相似文献   
48.
The use of electric vehicles (EVs) is viewed as an attractive option to reduce CO2 emissions and fuel consumption resulted from transport sector, but the popularization of EVs has been hindered by the cruising range limitation and the charging process inconvenience. Energy consumption characteristics analysis is the important foundation to study charging infrastructures locating, eco-driving behavior and energy saving route planning, which are helpful to extend EVs’ cruising range. From a physical and statistical view, this paper aims to develop a systematic energy consumption estimation approach suitable for EV actual driving cycles. First, by employing the real second-by-second driving condition data collected on typical urban travel routes, the energy consumption characteristics analysis is carried out specific to the microscopic driving parameters (instantaneous speed and acceleration) and battery state of charge (SOC). Then, based on comprehensive consideration of the mechanical dynamics characteristics and electric machine system of the EVs, a set of energy consumption rate estimation models are established under different operation modes from a statistical perspective. Finally, the performance of proposed model is fully evaluated by comparing with a conventional energy consumption estimation method. The results show that the proposed modeling approach represents a significant accuracy improvement in the estimation of real-world energy consumption. Specifically, the model precision increases by 25.25% in decelerating mode compared to the conventional model, while slight improvement in accelerating and cruising mode with desirable goodness of fit.  相似文献   
49.
荆晓 《中国海事》2011,(3):44-46
文中通过对方便旗船中国籍船员保险保障现状的调查分析,找出涉及外派船员权益方面存在的问题,提出相应海事监管对策。  相似文献   
50.
The present study tries to see whether the subsidy given to CSTC, which is the oldest and the largest state transport corporation operating in and around Kolkata, is really being used to cover the losses they make over the years or to merely cover-up an inefficient performance. The state owned buses are required to serve, not only non-profitable routes in off-peak hours, but also to give social security or employment to a large section of society. The burden of carrying a huge staff structure and serving at an administered and less than competitive price for welfare reasons, makes CSTC liable to an operating loss. Therefore, it makes a case for subsidy. However, the regular commuters experience regarding the condition of and the services provided by these raises a question about the justification of subsidy. In the study it is seen that the subsidy given is not based on any of the components on which it should, economically.  相似文献   
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