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91.
章群  严世榕 《机电工程》2016,(12):1506-1510
针对纯电动汽车上动力锂电池等效模型参数辨识的问题,以某纯电动汽车的由87个单体串联的84 Ah的镍钴锰三元锂电池组为研究对象,基于市区行驶的电池数据,选用了二阶RC电池等效模型,辨识了等效模型的参数。基于整体电池数据,选取出了8段在连续的12个(及12个以上)采样周期内相邻两个采样点的电流变化绝对值超过0.2 C的电池数据段,分别对初始开路电压最大和最小的单体进行了参数辨识。以最小二乘法对电流连续变化最长的一段电池数据段作为参数辨识的结果,并结合整体电池数据对辨识得的结果进行了参数的验证。研究结果表明,初始开路电压最大单体的绝对误差平均值为3.62%,初始开路电压最小单体的绝对误差平均值为3.24%,满足工程要求,可运用于工程实践中。  相似文献   
92.
As automation in vehicles becomes more prevalent, the call for understanding the behaviour of the driver while driving an automated vehicle becomes more salient. Although a variety of driver behaviour models exist, and various psychological constructs have been said to be influenced by automation, an empirically testable psychological model of automated driving has yet to be developed. Building upon Stanton and Young's model of driving automation, this article presents an updated model of interrelated psychological constructs. The proposed model was created based upon a systematic literature search of driving automation papers and a subsequent quantification of the number of reported links between a selected set of psychological constructs. A secondary aim of this article is to reach consensus in the use of psychological constructs regarding driving automation. Henceforth special attention is paid to resolving the issue of construct proliferation.  相似文献   
93.
94.
针对长平公司43311巷掘进工作面的支护劳动强度高、作业中存在安全隐患等问题,结合43311掘进工作面特征,合理选用支护方式和支护参数,对支护设计方案进行校核。结果表明,43311巷道选择的断面和支护方式、参数满足安全生产要求。  相似文献   
95.
In this paper, a boundary version of the Schwarz lemma is investigated for driving point impedance functions and its circuit applications. It is known that driving point impedance function, Z(s) = 1 + cp(s − 1)p + cp + 1(s − 1)p + 1 + ..., p > 1, is an analytic function defined on the right half of the s-plane. Two theorems are presented using the modulus of the derivative of driving point impedance function, |Z(0)|, by assuming the Z(s) function is also analytic at the boundary point s = 0 on the imaginary axis with . In the obtained inequalities, the value of the function at s = 1 and the derivatives with different orders have been used. Finally, the sharpness of the inequalities obtained in the presented theorems is proved. Simple LC circuits are obtained using the obtained driving point impedance functions.  相似文献   
96.
This paper describes the design and evaluation of a model predictive control algorithm for automated driving on a motorway using a vehicle traffic simulator. For the development of a highly automated driving control algorithm, motion planning is necessary to satisfy driving condition in various road traffic situations. There are two key issues in motion planning of automated driving vehicles. One of the key issues is how to handle potentially dangerous situations that could occur in order to guarantee the safety of vehicles. The second key issue is how to guarantee the disturbance rejection of the controller under model uncertainties and external disturbances. To improve safety with respect to the future behaviors of subject vehicles, not the current states but rather the predicted behaviors of surrounding vehicles should be considered. The desired driving mode and a safe driving envelope are determined based on the probabilistic prediction of surrounding vehicles behaviors over a finite prediction horizon. To obtain the desired steering angle and longitudinal acceleration for maintaining the subject vehicle in the safe driving envelope during a finite prediction horizon, a motion planning controller is designed based on an model predictive control (MPC) approach. The developed control algorithm has been successfully implemented on a vehicle electronic control unit (ECU). The proposed control algorithm has been evaluated on a real-time vehicle traffic simulator. The throttle, brake, and steering control inputs and the controlled vehicle behavior have been compared to those of manual driving.  相似文献   
97.
IntroductionIn 2010, British Columbia (BC) introduced new traffic laws designed to deter impaired driving, speeding, and distracted driving. These laws generated significant media attention and were associated with reductions in fatal crashes and in ambulance calls and hospital admissions for road trauma.ObjectiveTo understand the extent and type of media coverage of the new traffic laws and to identify how the laws were framed by the media.MethodsWe reviewed a database of injury related news coverage (May 2010–December 2012) and extracted reports that mentioned distracted driving, impaired driving, or speeding. Articles were classified according to: (i) Type, (ii) Issue discussed, (iii) ‘Reference to new laws’, and (iv) ‘Pro/anti traffic law’. Articles mentioning the new laws were reread and common themes in how the laws were framed were identified and discussed.ResultsOver the course of the study, 1848 articles mentioned distraction, impairment, or speeding and 597 reports mentioned the new laws: 65 against, 227 neutral, and 305 supportive. Reports against the new laws framed them as unfair or as causing economic damage to the entertainment industry. Reports in favor of the new laws framed them in terms of preventing impaired driving and related trauma or of bringing justice to drinking drivers. Growing evidence of the effectiveness of the new laws generated media support.ConclusionsBC's new traffic laws generated considerable media attention both pro and con. We believe that this media attention helped inform the public of the new laws and enhanced their deterrent effect.  相似文献   
98.
Using North Carolina administrative data, this study examined recidivism following participation in specialty hybrid drug and driving while intoxicated (DWI) court programs. Three court program participation levels were considered—being referred to, enrolling in, and completing a specialty court program. Measures of DWI recidivism were: arrest and total number of arrests for DWI, and being convicted of DWI during follow-up periods of two and, alternatively, four years. Propensity score matching was used to obtain comparable control groups. Using a four-year follow-up, persons convicted of a DWI who completed a specialty court program were associated with a greater reduction in DWI re-arrests and re-convictions than did matched individuals who were never referred to a specialty court program. DWI courts were more effective in reducing re-arrests than hybrid drug courts were. Although promising from the vantage point of participants, few persons convicted of a DWI were referred to either court type, thus limiting this strategy’s potential effectiveness in reducing DWI.  相似文献   
99.
《Ergonomics》2012,55(6):780-790
Abstract

Prospective memories can divert attentional resources from ongoing activities. However, it is unclear whether these effects and the theoretical accounts that seek to explain them will generalise to a complex real-world task such as driving. Twenty-four participants drove two simulated routes while maintaining a fixed headway with a lead vehicle. Drivers were given either event-based (e.g. arriving at a filling station) or time-based errands (e.g. on-board clock shows 3:30). In contrast to the predominant view in the literature which suggests time-based tasks are more demanding, drivers given event-based errands showed greater difficulty in mirroring lead vehicle speed changes compared to the time-based group. Results suggest that common everyday secondary tasks, such as scouting the roadside for a bank, may have a detrimental impact on driving performance. The additional finding that this cost was only evident with the event-based task highlights a potential area of both theoretical and practical interest.

Practitioner Summary: Drivers were given either time- or event-based errands whilst engaged in a simulated drive. We examined the effect of errands on an ongoing vehicle follow task. In contrast to previous non-driving studies, event-based errands are more disruptive. Common everyday errands may have a detrimental impact on driving performance.  相似文献   
100.
郑云龙 《煤》2012,(3):9-10
文章通过对潞安环能股份公司常村煤矿掘进机内喷雾系统,在实际应用过程中存在的问题进行分析,对原有悬臂段的水路结构进行技术改造,解决喷雾水因密封失效对悬臂段内轴承带来的损坏,以及造成切割电机进水后跳闸等问题,同时,对改善工作面的喷雾效果和工作面的作业环境具有积极意义。  相似文献   
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