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In this paper, we used the 10-wave Puget Sound Panel Dataset to investigate the response lag of a significant change in discretionary
time use. In particular, we want to quantify the relative magnitude of the following factors: the built environment, family
and social obligations, temporal constraints, or a psychological delay factor (people delay a behavioral change until the
next life shock). To answer this question, we developed a survival model to treat (1) left-censoring, (2) partial observation,
and (3) multi-type exits. The results suggest that family and social obligations, as well as temporal constraints, appear
to play a more important role than the built environment. Support for the psychological delay factor is not evident. We also
found that the probability of having a significant change in discretionary time use is negatively related to time progression,
supporting the human adaptivity hypothesis.
Cynthia Chen is an assistant professor of Civil Engineering at the City College of New York. Her recent research interests have been in travel behavior dynamics and residential search and location process. Jason Chen is a Ph.D. candidate in the department of civil engineering at the City University of New York. His research interests include travel behavior analysis, travel demand modeling, and residential location analysis. 相似文献
Jason ChenEmail: |
Cynthia Chen is an assistant professor of Civil Engineering at the City College of New York. Her recent research interests have been in travel behavior dynamics and residential search and location process. Jason Chen is a Ph.D. candidate in the department of civil engineering at the City University of New York. His research interests include travel behavior analysis, travel demand modeling, and residential location analysis. 相似文献
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针对无信号畸形交叉口有别于规则交叉口的几何特性,以及因几何特性的不同而带来的安全问题,通过分析驾驶员在畸形交叉口处观察相交道路车辆情况的过程与特点,利用多自由度驾驶仿真平台,对驾驶员在畸形交叉口的驾驶操作及视认特性进行实验,并根据实验所得数据,提出基于驾驶员视认性的畸形交叉口安全视距计算方法,从而得到基于驾驶员视认性的畸形交叉口视距的计算,并对畸形交叉口平面设计进行建议改善,以满足安全通行的需求。 相似文献
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曲线拟合是沉降评估的重要步骤,处理方法和过程比较复杂,需要编制专门程序进行数据处理与计算.作者利用Excel中的规划求解功能,分步实现沉降观测中的曲线方程拟合;利用Excel的表格功能,可实现沉降预估指标的计算.本文叙述的方法直接利用Excel的数据格式和功能,方便快捷,能满足铁路沉降观测计算的需要,方便工程技术人员掌握和应用. 相似文献
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高真空击密法是加固饱和软土的一种新工艺方法。介绍高真空击密法的加固机理及工艺流程,并通过对高真空击密法在曹妃甸通岛公路路基工程中的成功应用,表明该软土加固方法不仅具有清晰的理论概念、有效的加固效果和低廉的工程造价,而且具有广阔的应用前景。 相似文献
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船舶轴系是船舶动力装置中的重要组成部分,其功能是将主机发出的功率传递给螺旋桨,再将螺旋桨产生的轴向推力传递给船体实现推船航行.轴系的安装质量直接关系到主机推进系统运转的可靠性和船舶的安全航行.通过从生产准备、轴系校准、轴承浇注、尾轴安装等方面,介绍了结合拉线法与望光法确定轴系理论中心线,使用环氧树脂浇注尾轴承,轴系安装及下水后的调整,最后通过该船型的试航情况分析证明安装质量是合格的. 相似文献
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Hang Tuah. Salim 《水道港口》2010,31(5):321-321
Belawan is the largest port serving North Sumatra for the import and export.Port has facilities for handling container,CPO liquid bulk cargo,Oil,and other agriculture products.Its location is at the river mouth which is subjected to the heavy sedimentation especially after many deforestation activities in its catchment area. The numerical modeling was developed for predicting the rate of sediment caused by erosion in the catchment area for several scenarios.This predicted rate of sediment was applied as input to model of sedimentation in the ocean.Present condition of sedimentation data was used as calibrated data.This integrated model was used to simulate the sedimentation in Belawan access channel and harbor basin for several development plans. 相似文献