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排序方式: 共有196条查询结果,搜索用时 31 毫秒
51.
为优化城市轨道交通自动售检票系统回收类票卡的库存、调配管理,根据系统提供的大量时序数据,设计了一个基于"ARIMA+RBF"的组合预测模型,利用组合模型预测回收类与非回收类票卡的比例趋势、每周回收类票卡使用数量,以及每周遗失回收类票卡数量。结果表明,组合模型预测的精度要比单纯ARIMA模型要高,可以用作票卡库存管理的理论依据。将其应用到回收类票卡的采购、库存及调配等方面,可以减少运营成本、提高服务质量。 相似文献
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A latent class model is developed to accommodate preference heterogeneity across commuters with respect to their mode choice between electric bike, private car, and public bus within the context of China. A three-segment solution – ‘electric bike individuals’, ‘private car addicts’, and ‘public bus enthusiasts’ – is identified, each characterized by heterogeneous preferences regarding specific mode attributes and unique socio-demographic profile. The choice model confirms the determinative effects of perceived alternative attributes on commuting mode choice, while the traditionally used objective attributes – travel time and cost – are found to have relatively small influences. The membership model provides solid explanations for these segment-specific preferences. This study provides a better understanding of the nature of mode choice behavior, which can be useful for strategies tailored to a specific segment in order to promote the use of sustainable transport modes. 相似文献
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舰船IETM系统能辅助舰船级维修,极大提高了舰船级维修能力。为了使IETM能更好地服务于舰船级维修,根据舰船级维修的特点和需求,针对目前已处于先进水平的第4级IETM提出进一步功能增值的要求,并拓展其功能模块。增加了故障智能诊断与预测系统模块、数据上传/下载模块。功能增值后的IETM可进一步增强舰船级维修能力,保障舰船战备完好性。 相似文献
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针对TMIS车站系统在建设实施中出现的统计功能的不足之处,提出了完善系统统计功能的思路和实现方式,并结合郑州东车站系统的建设实际,以班统计为例,予以较为具体的阐述. 相似文献
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Plug-in hybrid electric vehicles (PHEVs) can provide many of the benefits of battery electric vehicles (BEVs), such as reduced petroleum consumption and greenhouse gas emissions, without the “range anxiety” that can accompany driving a vehicle with limited range when there are few charging opportunities. However, evidence indicates that PHEVs are often plugged in more frequently than BEVs in practice. This is somewhat paradoxical: drivers for whom plugging in is optional tend to do so more frequently than those for whom it is necessary. This has led to the coining of a new term – “gas anxiety” – to describe the apparent desire of PHEV drivers to avoid using gasoline. In this paper, we analyze the variables influencing the charging choices of PHEV owners, testing whether drivers express preferences consistent with the concept of gas anxiety. We analyze data collected in a web-based stated preference survey using a latent class logit model. The results reveal two classes of decision-making patterns among the survey respondents: (1) those who weight the cost of gasoline and the cost of recharging approximately equally (the cost-minimizing class), and (2) those who weight the cost gasoline more heavily than the cost of recharging (the gas anxiety class). Respondents in the gas anxiety class expressed a willingness to recharge at a charging station even when doing so would cost approximately four times as much as the cost of the gasoline avoided. While the gas anxiety class represents the majority of our sample, more recent PHEV adopters are more likely to be in the cost-minimizing class. Looking forward, this suggests that public charging station operators may need to price charging competitively with gasoline on a per-mile basis to attract PHEV owners. 相似文献
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利用C 语言的面向对象特性对OpenGL功能进行了封装,使其能够方便地与Visuak C 的MFC相结合;采用了面向对象的技术进行了程序设计;与传统的OpenGL与Visual C 相结合的方法比较,新的封装技术保持了部分功能的独立性,有利于软件的维护和二次开发。 相似文献