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151.
针对电力机车二系悬挂调簧分析数学模型算法的优化问题,提出一种遗传算法(GA)与蚂蚁算法(AA)相结合的混合优化算法。其基本思想是:首先采用遗传算法以较少的进化代数进行全局快速随机搜索,获得若干可能的(近似)优化解,以此生成蚂蚁算法初始信息素分布,再用后者求得全局优化精确解。对国产SS3B和SS9型机车的应用结果表明,对同一车体进行多次优化计算试验,混合优化算法的搜索寻优过程均能稳健一致地收敛到全局优化解,可明显缩短二系支承载荷调整调簧计算所需时间,使调簧试验的实时性大为提高。对于二系为高圆簧的SS9型机车,混合算法平均用时比迭代算法和单一遗传算法分别减少约74%和29%。  相似文献   
152.
While discrete choice analysis is prevalent in capturing consumer preferences and describing their choice behaviors in product design, the traditional choice modeling approach assumes that each individual makes independent decisions, without considering the social impact. However, empirical studies show that choice is social – influenced by many factors beyond engineering performance of a product and consumer attributes. To alleviate this limitation, we propose a new choice modeling framework to capture the dynamic influence from social networks on consumer adoption of new products. By introducing social influence attributes into a choice utility function, social network simulation is integrated with the traditional discrete choice analysis in a three-stage process. Our study shows the need for considering social impact in forecasting new product adoption. Using hybrid electric vehicles as an example, our work illustrates the procedure of social network construction, social influence evaluation, and choice model estimation based on data from the National Household Travel Survey. Our study also demonstrates several interesting findings on the dynamic nature of new technology adoption and how social networks may influence hybrid electric vehicle adoption.  相似文献   
153.
The 2005 California Clean Air Access Sticker program offered stickers to owners of hybrid cars allowing unrestricted access to High Occupancy Vehicle lanes. The program was conceived as a zero-cost mechanism to encourage purchase of hybrid cars and to reduce air pollution. Information from sales of used hybrids allows us to estimate sticker market value. We then derive the value of excess HOV space the hybrids occupied, which is considerably greater than the air pollution benefits achieved. A more effective policy would sell space to drivers of any vehicle and use the revenue to stimulate hybrid demand, preferably via direct subsidy.  相似文献   
154.
本文主要针对气电混合动力公交车的经济性进行了研究,并通过路谱采集分析燃气发动机实际常用工作区域,结合发动机燃烧特性分析发动机燃气经济性。并通过对电控发动机重新标定达到气耗百公里降低2-3公斤。  相似文献   
155.
This research presents an integrated optimal controller to maximize the fuel efficiency of a Hybrid Electric Vehicle (HEV) traveling on rolling terrain. The controller optimizes both the vehicle acceleration and the hybrid powertrain operation. It takes advantage of the emerging Connected Vehicle (CV) technology and utilizes present and future information as optimization input, which includes road topography, and dynamic speed limit. The optimal control problem was solved using Pontryagin’s Minimum Principle (PMP). Efforts were made to reduce the computational burden of the optimization process. The evaluation shows that the benefit of the proposed optimal controller is significant compared to regular HEV cruising at the speed limit on rolling terrain. The benefit ranges from 5.0% to 8.9% on mild slopes and from 15.7% to 16.9% on steep slopes. The variation is caused by the change of hilly road density.  相似文献   
156.
Some South African cities have initiated public transport transformation projects which, in most cases, ultimately envisage the in toto replacement of paratransit operations with formalised BRT systems. There are two likely outcomes: (1) complex negotiations with existing operators and budget constraints will result in the in toto transformation occurring over an extended period of time; or (2) in toto transformation will simply not occur. In either case, cities will depend, for decades, on a ‘hybrid’ public transport system that combines both formal and paratransit operators. This paper presents a case for policy recognition of hybrid systems, and explores how such systems might best be managed. The following categories of hybrid public transport systems are explored through case studies: (1) transformative processes in which paratransit operators are to form or assimilate into companies to operate new services, but this incorporation has proved difficult to complete and the operational and regulatory frameworks remain unchanged; and (2) transformative processes that, from the outset, anticipated a hybrid system and designed the outcome accordingly. A third category of hybrid transport systems, defined as transformative processes that have been amended following a realisation that in toto transformation is unattainable, is also introduced and discussed. The paper concludes by tentatively drawing lessons for appropriate public transport regulation, particularly with respect to Cape Town's transformation project. It is argued that a review of the current national regulatory framework is required to enable possible project modifications that acknowledge system hybridity. It is suggested that regulatory frameworks that accommodate the likely hybrid nature of public transport system outcomes have greater prospects of success than frameworks that do not. Furthermore, it is argued that contextually appropriate and successful public transport transformation projects do not necessarily require the in toto substitution of incumbent paratransit operators, and that they can be integrated with, and complement, formal services.  相似文献   
157.
HC9S12单片机在混合动力汽车ISG控制系统中的应用   总被引:3,自引:2,他引:1  
基于MC68HC9S12DP256B单片机,研制了混合动力汽车(HEV)集成化动力总成(ISG)控制系统,提出了软硬件设计、电机和动力电池的模糊控制和动力总成的控制策略。  相似文献   
158.
尉进  赵韩  江昊 《汽车科技》2012,(3):70-75
基于飞思卡尔公司的双核微控制器9S12XDT512开发了一款通用的混合动力汽车(HEV)整车控制器(VehicleControl Unit-VCU),设计时考虑硬件的通用性,使之能够适用于多种混合动力汽车的整车控制。为验证VCU功能,本文以某款并联混合动力公交车为控制对象,在基于dSPACE的硬件在环仿真系统上进行了一系列仿真试验。试验结果表明:VCU能够准确地控制整车实现混合动力工作状态,进而验证了VCU硬件的有效性。  相似文献   
159.
高健 《天津汽车》2012,(3):17-19
节能与环保已经成为汽车技术发展的2大主题。文章通过对丰田混合动力轿车的系统构成和工作原理的叙述,以及对于混合动力汽车发展现状及趋势的分析,说明了混合动力电动汽车在节能减排方面效果显著,克服了普通电动汽车行驶里程短及充放电技术落后等缺点。表明混合动力电动汽车将成为未来汽车产品的发展方向。  相似文献   
160.
汽车的实际行驶条件对汽车性能具有直接影响。对于混合动力汽车,其部件的选型以及控制策略的制定都与道路行驶工况密切相关文章对汽车行驶工况做了相应的分析.利用GT—DRIVE软件对某微型混合动力汽车进行了建模与仿真仿真结果表明,在经济性方面混合动力汽车比传统汽车有明显的优势.如何更好地分配混合动力汽车功率将是混合动力汽车研究的重点.  相似文献   
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