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81.
An integrated spatio-temporal GIS toolkit for exploring intra-household interactions 总被引:1,自引:0,他引:1
This paper reports on the development of an integrated spatio-temporal GIS toolkit that facilitates the exploration of intra-household
interactions. Two tools comprise the toolkit. The first tool, Space-Time Coincidence Analyst, identifies joint activity/travel episodes undertaken by household members. The core of this tool is a set of flexible criteria
for classifying episodes as either joint or independent. The second tool, Space-Time Path Visualizer, not only displays space-time paths for household members, but also shows joint episodes undertaken by any two household
members together. The toolkit can be applied to any household-based, activity/travel data set so long as required information
is specified by the user. To demonstrate its usefulness for research, the toolkit is applied to the TAPS (Toronto Activity
Panel Survey) 2002–03 data set. The results suggest that considerable variation exists in the number of joint activity/travel
episodes identified using different classification criteria. Specifically, when using restrictive criteria (i.e., same timing,
specific activity type/travel mode), only 2,265 joint activity/travel episodes are identified compared to 8,791 when using
more flexible criteria. In turn, our results show that certain key attributes for independent and joint activity/travel episodes
(i.e., frequency per household, starting time, ending time and duration) also vary under the different classification criteria.
Hejun Kang is a PhD candidate in the School of Geography and Earth Sciences at McMaster University. She holds a MSc degree in Geographic Information Science from the University of Calgary. Her doctoral research concerns intra-household interactions in the context of activity/travel behavior. Darren M. Scott is an Associate Professor of Geography at McMaster University. His current research centers on inter-agent decision making with regards to activity/travel behavior, and on issues concerning aggregation in activity-based travel demand models, most notably the treatment of space and the classification of activities. 相似文献
Darren M. ScottEmail: |
Hejun Kang is a PhD candidate in the School of Geography and Earth Sciences at McMaster University. She holds a MSc degree in Geographic Information Science from the University of Calgary. Her doctoral research concerns intra-household interactions in the context of activity/travel behavior. Darren M. Scott is an Associate Professor of Geography at McMaster University. His current research centers on inter-agent decision making with regards to activity/travel behavior, and on issues concerning aggregation in activity-based travel demand models, most notably the treatment of space and the classification of activities. 相似文献
82.
83.
By scale model tests, it proves the mechanism mode of shear resistance borne by friction of contact area and concrete shear key in different contact stress states and cushion thicknesses of shear key. The results show that friction plays a significant role on shear resistance of element joint. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved. 相似文献
84.
The blade loading contains sufficient information about the unsteady aerodynamics of Floating Wind Turbines (FWTs), and it serves as the basis for advanced controller developments. Wave basin model test is among the most reliable and economical methods for FWT investigations. However, few FWTs were reported being able to monitor the blade loads during wave basin tests. The main obstacles include strict space/mass limitations in model manufacturing and problems associated with signal transmission between rotating blades and stationary signal processing unit. In this paper, the feasibility of detecting blade loads for model FWT in wave basin tests is investigated. An on-line monitoring system is developed based on Fiber Bragg Grating (FBG) sensors and a Fiber Optical Rotary Joint (FORJ). Extensive validation tests are conducted under different environmental and operational conditions. Results show that the proposed FBG-FORJ sensing system presents impressive feasibility and reliability. As the authors know, it is among the first attempts to monitor the blade loads in real-time for model FWTs in wave basin tests. The present study will serve to enrich the knowledge about unsteady aerodynamics of FWTs and lay the foundation for experimental studies on advanced FWT controllers. 相似文献
85.
在总结我国分离式和合并式合建建筑振动转播路径和动力特性的基础上,评述不同类型的既有合建建筑动力响应及振动控制的工程实测和数值分析的研究现状。结果表明:相较于临近地铁建筑,合建建筑在振动强度、激振频段、低频敏感频段、水平振动量级和振动形态等方面具有显著不同;为改善合建建筑的振动环境,可通过降低车体重量、改善轮轨接触面和选择适合的减振轨道与扣件等手段对振源进行振动控制,还可采用整体浮置或局部浮置等隔振方法进行上部结构振动控制。为此,应在适用于合建建筑的通用耦合计算模型、减振轨道实际控制效果、制定匹配合建建筑的振源频率、开发具有针对性的隔振装置产品、浮置隔振中参数优化与关键部位的构造设计等领域进行深化研究。 相似文献
86.
87.
客车结构杆连接的真实形状对结构计算的影响 总被引:15,自引:0,他引:15
本文应用有限元分析法,研究了承载式客车底加中4种基本结构的杆连接的真实形状对结构扭转变形和应力计算的影响。 相似文献
88.
为满足空间飞行器结构中圆管接头模拟分析的需要,在AutoCADAME的基础上实现了圆管接头的有限元网格剖分。该方法在实际工程中得到广泛应用,并取得了令人满意的效果。 相似文献
89.
船闸运行管理体制是否顺畅,关系到内河水运事业的发展。文章以西江黄金水道百色至梧州船闸为例,分析了船闸管理体制存在的主要问题与原因,提出了改革船闸管理体制的思路与方法。 相似文献
90.
A large number of offshore platforms of various types have been installed in deep or shallow waters throughout the world. These structures are mainly made of tubular members which are interconnected by using tubular joints. In tubular frames, joints may exhibit considerable flexibility in both elastic and plastic range of response. The resulting flexibility may have marked effects on the overall behavior of offshore platforms.This paper investigates the effects of joint flexibility on local and global behavior of tubular framed structures in linear range of response. A new joint flexibility element is developed on the basis of flexibility matrix and implemented in a finite-element program to account for local joint flexibility effects in analytical models of tubular framed structures. The element formulation is considerably easy and straightforward in comparison with other existing tubular joint elements. It was concluded that developed flexible joint model produces accurate results comparing to sophisticated multi-axial finite element joint models. 相似文献