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排序方式: 共有725条查询结果,搜索用时 265 毫秒
471.
本文通过对消费者信息处理过程的阶段分析,阐述低碳消费的观念作为公益广告的形式在传播中的信息传达阶段和信息扩散阶段的流程节点。在公益广告传播中要通过各种表现形式引导消费者对低碳消费信息认知,其次从正面的信息传达和反面的"警钟诉求"来塑造大众与低碳消费信息的情感,最后通过直接的信息诉求激励和间接的降低"充欲主义"的影响来促使消费行为发生乃至形成习惯。 相似文献
472.
Budi S. Prasodjo Kimio Saito Yasushi Higo Hisashi Nobukawa Katsuya Maeda 《Journal of Marine Science and Technology》2006,11(4):260-269
This article discusses the dynamic responses of a coastal cargo ship that consists of unit modules with advance forward speed
in waves. We introduce a simple way of connecting the modules that has enough capability to link the modular parts of the
ship as a unified whole. The flexible connection consists of male and female rubber fenders with additional pretensioned ropes.
This kind of connection system is proposed for use in coastal regions with relatively calm waters wherein the modular ship
can move at a moderate speed. The modules are assumed to be rigid compared to the connections. Computations were performed
to investigate the vertical elastic responses of four modules connected end-to-end with the assumption that in the simple
hinge, no gaps occur in the flexible rubber connections between adjacent modules. A simple method, which is an extension of
the computational analysis we reported previously, is presented to study the hydroelasticity and rope tension forces of the
modular ship with forward speed in waves. Experiments with a three-dimensional model at Froude numbers of 0 and 0.16 in head
waves were performed to evaluate the effectiveness of the calculation method. In the experiments, deflections for each part
were measured using calibrated potentiometers. Force transducers were used to measure the rope tension force between the modules
of the articulated cargo ship. Some slight differences were observed, but generally the calculated results showed the same
trends as the experimental values. 相似文献
473.
用于地面带电自动过分相的智能选相真空断路器的研究 总被引:2,自引:0,他引:2
真空断路器是地面带电相分段自动转换装置的关键设备。通过对自动过分相系统暂态过程的分析,研究开发了采用永磁操作机构的智能选相真空断路器。现介绍研制采用的单稳态永磁操作机构、高压真空灭弧室、断路器同步关合技术的具体实施方案,以及智能选相真空断路器成功应用于地面带电自动过分相技术的现状。 相似文献
474.
This study analyzes the problem of conflicting travel time and emissions minimization in context of daily travel decisions. The conflict occurs because the least travel time option does not always lead to least emissions for the trip. Experiments are designed and conducted to collect data on daily trips. Random parameter (mixed) logit models accounting for correlations among repeated observations are estimated to find the trade-off between emissions and travel time. Our results show that the trade-off values vary with contexts such as route and departure time choice scenarios. Further, we find that the trade-off values are different for population groups representing male, female, individuals from high income households, and individuals who prefer bike for daily commute. Based on the findings, several policies are proposed that can help to lower greenhouse gas (GHG) emissions from transportation networks. This is one of the first exploratory studies that analyzes travel decisions and the corresponding trade-off when emissions related information are provided to the road users. 相似文献
475.
软交换技术是未来公众网的重要组成技术,介绍软交换技术在辽宁铁通的应用情况,阐述软交换技术网络的优势、特点,以及软交换的市场应用情况及业务推广策略,对于了解软交换技术和应用有一定的帮助。 相似文献
476.
在对铁路工程简支箱梁进行施工时,其核心环节就是箱梁张拉施工,箱梁张拉施工质量会给整个工程的施工质量造成严重影响。结合实际工程,认真分析预应力简支箱梁的实际施工情况,然后围绕市域铁路预应力简支箱梁张拉控制施工技术展开探讨。控制预应力张拉情况,要精确管控伸长量和张拉力,要以摩阻试验为依托,出现误差偏大需立即采取有效措施进行调整。 相似文献
477.
《铁道标准设计通讯》2017,(7):71-75
西江特大桥是广佛江珠城际铁路的重要桥梁,为取得主桥合理的桥式方案,遵循"安全、实用、经济、美观"的设计原则,按照单向通航和双向通航的净空要求,采用钢桁拱桥、钢桁斜拉桥及矮塔斜拉桥,对4种桥型设计方案进行对比分析计算,综合考虑施工难度、景观效果、通航条件及工程造价等因素,最终得出双孔252 m钢桁拱桥为推荐方案。 相似文献
478.
王志荣 《城市轨道交通研究》2016,(6):128-132
初步研究了重庆铜梁试验线交直供电系统间设置的中性段供电切换方案。在线路条件允许的情况下,建议双流制列车通过接触网中性段时采用不停车、不降弓的车上切换方式进行供电切换。接触网中性段位置宜选择在地面或高架区段。 相似文献
479.
描述了目前城市轨道交通公务电话系统的现状,分析了在技术、设计、管理等方面存在的问题,并通过对软交换技术应用于城市轨道交通适应性等方面的论述,提出了城市轨道交通公务电话系统建设的思路和建议方案,以提高系统投资的有效性和性价比。 相似文献
480.
This paper analyses the results of the Royal Automobile Clubhallo’s 2011 RAC Future Car Challenge, an annual motoring challenge in which participants seek to consume the least energy possible while driving a 92 km route from Brighton to London in the UK. The results reveal that the vehicle’s power train type has the largest impact on energy consumption and emissions. The traction ratio, defined as the fraction of time spent on the accelerator in relation to the driving time, and the amount of regenerative braking have a significant effect on the individual energy consumption of vehicles. In contrast, the average speed does not have a great effect on a vehicles’ energy consumption in the range 25–70 km/h. 相似文献