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321.
随着大跨桥梁的迅猛发展和对大跨桥梁施工、运营期间的健康状况的日益关注,大跨桥梁健康监测系统及其理论、应用成为了桥梁工程界内人士研究和发展的热点。主要阐述了大跨桥梁健康监测系统的发展和概念、健康监测系统的组成、健康监测系统的设计、理论进展等内容。 相似文献
322.
Charles Musselwhite 《运输规划与技术》2015,38(1):44-61
Traditionally, theory suggests the ageing individual is strongly influenced by the environment and has difficulties in overcoming distance and space. Recently, however, theory has moved to suggest that older people possess greater agency, being more capable of selecting and mastering their environments and spaces according to their needs and preferences. This paper suggests that both opposing theories are correct for differing groups. Observations and surveys of older people (n = 365) in public space examined how far person–environment agency is present in active use of outdoor space, measured by confidence to use and explore space, in three locations (urban shopping centres, suburban residential area and an area of shared space). In all three areas, dominance of the space was associated with being male and having higher levels of reported health, confidence and higher socio-economic status. Only 11% of participants walked at least as fast as the UK department for transport guidance on crossing speeds. 相似文献
323.
With the approach of introducing the conceptions of mental account and mental budgeting into the process of travelers’ route choice, we try to identify why the usages of tolled roads are often overestimated. Assuming that every traveler sets a mental account for his/her travel to keep track of their expense and keep out-of-pocket spending under control, it addresses these questions such that “How much money can I spend on the travel?” and “What if I spend too much?”. Route tolls that exceed the budget are much more unacceptable compared to those within budget due to the non-fungibility of money between different accounts. A simple network with two nodes and two routes is analyzed firstly, the analytical solutions are obtained and the optimal road tolls supporting the user equilibrium as a system optimum are also derived. The proposed model is then extended to a generalized network. The multiclass user equilibrium conditions with travel mental budgeting are formulated into an equivalent variational inequality (VI) problem and an equivalent minimization problem. Through analyses with numerical examples, it is found that the main reason that the usages of high tolled roads are often overestimated is due to the fact that travelers with low and moderate out-of-pocket travel budget perceive a much higher travel cost than their actual cost on the high tolled roads. 相似文献
324.
Leandro L. Di Stasi Rebekka RennerAndrés Catena José J. Cañas Boris M. Velichkovsky Sebastian Pannasch 《Transportation Research Part C: Emerging Technologies》2012,21(1):122-133
Developing a valid measurement of mental fatigue remains a big challenge and would be beneficial for various application areas, such as the improvement of road traffic safety. In the present study we examined influences of mental fatigue on the dynamics of saccadic eye movements. Based on previous findings, we propose that among amplitude and duration of saccades, the peak velocity of saccadic eye movements is particularly sensitive to changes in mental fatigue. Ten participants completed a fixation task before and after 2 h of driving in a virtual simulation environment as well as after a rest break of fifteen minutes. Driving and rest break were assumed to directly influence the level of mental fatigue and were evaluated using subjective ratings and eye movement indices. According to the subjective ratings, mental fatigue was highest after driving but decreased after the rest break. The peak velocity of saccadic eye movements decreased after driving while the duration of saccades increased, but no effects of the rest break were observed in the saccade parameters. We conclude that saccadic eye movement parameters—particularly the peak velocity—are sensitive indicators for mental fatigue. According to these findings, the peak velocity analysis represents a valid on-line measure for the detection of mental fatigue, providing the basis for the development of new vigilance screening tools to prevent accidents in several application domains. 相似文献
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通过对社区卫生服务的功能需求出发,采用Z语言对系统规格进行了形式化说明,包括基础数据、系统状态以及系统操作等。采用形式化方法对社区卫生服务系统进行设计,能够得到一致的、精确的、简明的和无歧义的规格说明。 相似文献
329.
当前我国高职办学理念浅析 总被引:1,自引:0,他引:1
通过对当前我国高职教育的办学背景、内涵进行分析,提出了高职教育的办学策略.树立正确的办学理念对高职教育至关重要,高职院校应该切实把握高职教育的内涵,注重体现高职特色. 相似文献
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