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211.
Abstract

This paper explores social media's role in managing unplanned transit networks disruptions. Although literature exists more broadly on the use of social media in transit, this paper presents the first literature review in this setting. When disruptions occur, commuters require reliable, up-to-date information. Its provision reduces anxiety and allows informed choices. Social media is beneficial given it provides real-time information but it can only supplement (not replace) conventional approaches. Information reliability was critical. Research in the field of disaster management illustrates the importance of publicly contributed information. Known as “crowdsourcing”, it is part of the emerging field of crisis informatics which for the first time was linked to unplanned transit disruption management. The results highlight that social media's real-time nature can reduce disrupted travel demand; however, its utilisation can be resource-intensive. A framework presented illustrates how social media utilisation varies according to the operational characteristics of a disrupted network. Social media use as an information delivery tool is still in its infancy and an unwillingness to embrace it is an impediment to sustained growth. Crowdsourcing is one approach that could resolve the issue of transit agency resourcing whilst satisfying the increased demand and expectation for real-time information.  相似文献   
212.
本实验以鼓泡接种金黄色葡萄球菌的方法诱发豚鼠的化胀性中耳炎,用扫描电镜观察接种细菌后1、2、4及6周不同时间豚鼠柯蒂氏器的病理改变,发现受试动物的耳蜗各回均可见不同程度的毛细胞静纤毛异常、细胞缺失及支持细胞的损伤等。另外,本实验还显示了外毛细胞消失及支持细胞指状突修复前后的一些表现。  相似文献   
213.
基于ActiveX技术构建了B/S模式的交通视频监控系统,采用先进的H.264视频压缩算法和流媒体技术,很好解决了视频图像停顿、延迟和抖动的现象,实现对远程摄像头和云台的控制,实现多方位监控,并且大大降低了客户端的管理和维修费用.  相似文献   
214.
Conceptual and empirical models of the propensity to perform social activity–travel behavior are described, which incorporate the influence of individuals’ social context, namely their social networks. More explicitly, the conceptual model develops the concepts of egocentric social networks, social activities, and social episodes, and defines the three sets of aspects that influence the propensity to perform social activities: individuals’ personal attributes, social network composition, and information and communication technology interaction with social network members. Using the structural equation modeling (SEM) technique and data recently collected in Toronto, the empirical model tests the effect of these three aspects on the propensity to perform social activities. Results suggest that the social networks framework provides useful insights into the role of physical space, social activity types, communication and information technology use, and the importance of “with whom” the activity was performed with. Overall, explicitly incorporating social networks into the activity–travel behavior modeling framework provides a promising framework to understand social activities and key aspects of the underlying behavioral process. Juan Antonio Carrasco a PhD candidate in Civil Engineering at the University of Toronto, holds a MSc degree in Transportation Engineering from the Pontificia Universidad Católica de Chile. His doctoral research explores the relationships between social networks, activity–travel behavior, and ICTs. His research interests also include microsimulation, land use-transportation, and econometric modeling. Eric J. Miller is Bahen-Tanenbaum Professor of Civil Engineering at the University of Toronto where he is also Director of the Joint Program in Transportation. His research interests include integrated land-use/transportation modeling, activity-based travel modeling, microsimulation and sustainable transportation planning.  相似文献   
215.
豚鼠分泌性中耳炎动物模型建立的研究   总被引:1,自引:0,他引:1  
目的 研究建立分泌性中耳炎豚鼠动物模型的方法 ,为渗出性中耳炎的动物实验研究提供一种有用的动物模型。方法 采用灭活的肺炎链球菌悬液制备豚鼠分泌性中耳炎动物模型 ,了解渗出性中耳炎对听阈及中耳炎黏膜的病理改变。结果 听阈升高者 16耳 ,以低频为主 ,鼓膜呈浅黄色 ,病理改变主要在中耳腔 ,有不同程度的渗出 ,以浆液性为主。结论 细菌的分解产物———内毒素 ,导致中耳黏膜的炎症反应及中耳腔渗出 ,为进一步研究SOM提供动物模型  相似文献   
216.
结合实际应用,主要介绍了视频点播系统(VOD)的网络支持环境、视频服务器和用户访问控制三项关键技术。  相似文献   
217.
Exceptforinaminorityofthecaseswithearlystageotitismedia (OM)orsequelae ,effusionisthemostcommoninflammatoryproductamongthevar iousOMtype .Itisnotclearwhetheruntreatedef fusionresultsinchronic ,irreversible pathologicchangesinthemiddleearcleftandmastoid[1 -4 ] .Chronicotitismedia (COM)ismainlyindicatedbytheformationofgranulationtissue .Granulationtis sueisthemostcommon [5,6] andsignificantrepresenta tivepathologictissueofCOM .Studiesonthefac tors promoting granulationtissueformation ,thepat…  相似文献   
218.
文章根据社会网络理论中社会资本理论和结构洞理论,分析了信任关系在订单式教育实施过程中的重大作用,并提出了如何构建信任机制的方法和途径,以期对高职院校开展"订单式"教育有所启示。  相似文献   
219.
表面噪声矢量场空间相关特性射线声学建模(英文)   总被引:1,自引:0,他引:1  
Spatial correlation of sound pressure and particle velocity of the surface noise in horizontally stratified media was demonstrated,with directional noise sources uniformly distributed on the ocean surface.In the evaluation of particle velocity,plane wave approximation was applied to each incident ray.Due to the equivalence of the sound source correlation property and its directivity,solutions for the spatial correlation of the field were transformed into the integration of the coherent function generated by a single directional source.As a typical horizontally stratified media,surface noise in a perfect waveguide was investigated.Correlation coefficients given by normal mode and geometric models show satisfactory agreement.Also,the normalized covariance between sound pressure and the vertical component of particle velocity is proportional to acoustic absorption coefficient,while that of the surface noise in semi-infinitely homogeneous space is zero.  相似文献   
220.
论传媒对民族文化记忆的唤起   总被引:1,自引:0,他引:1  
民族文化记忆是确立民族身份、实现民族认同的历史资源.传媒对民族文化记忆的唤起处于一个复杂的"社会文本"中,在"记忆"某些历史的同时也选择性"遗忘"另一些历史;传媒通过纪念仪式和身体实践的方式唤起记忆,并以"拔高"、"简化"和"贴标签"的方式操纵记忆;政治经济权力是传媒建构文化记忆的影响因素,使得传媒对历史的再现出现了局部异化;而随着全球化和网络空间的崛起,多元主体对传媒记忆的解构正在展开,国家人、世界人、个体人的分化成为挑战民族文化记忆建构的一股力量.  相似文献   
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