柱状构筑物垂直度非接触检测方法及其精度分析

针对无明显特征点的柱状构筑物垂直度测量困难的问题,提出了一种全站仪非接触投影法.利用非接触的方法切准待测目标的外轮廓,测量其水平方向角和竖直角,依据测角度推算水平偏移量和倾斜率,并根据最小二乘原理分析了其测量精度.分析结果表明:仪器至立柱距离小于40 m,至所测断面中心的水平角小于1°时,水平偏移量中误差优于±2 mm,同时,竖直角在5~45°范围时,倾斜率测量中误差优于±0.4‰,完全满足检测精度要求.     

城市干路行人过街设施时空阈值研究

在传统的行人过街设施规划与设计中,片面强调机动交通的通行效率,常常给行人过街带来很大不便,同时造成安全隐患。首先回顾了国内外行人过街设施布局的相关研究,将上海市2条干路与巴黎、纽约和东京4条干路的行人过街设施进行对比,同时将国内外过街设施信号配时进行比较,揭示了我国城市干路行人过街设施规划及设计的缺陷。基于意愿调查,确定了少年、青年、老年3组行人在各级干路过街的绕行距离阈值和等候时间阈值。以两类阈值为准绳,结合过街步速观测,提出了城市干路过街设施间距阈值与信号控制的最长红灯时间和最短绿灯时间。     

基于孔内摄像的湘江长沙综合枢纽坝基岩体结构面判译与验证

坝基勘察期间,难以直接观测到坝基岩体中的结构面特征．通过在勘探孔中进行孔内摄像,能观测到孔壁各类裂隙面的特征．基坑开挖后,对揭露的岩体结构面进行编录统计．将两种方法获得的成果进行比较,验证了孔内摄像成果能较好地反映坝基岩体结构面特征．工程实例证明：孔内摄像可用于解决勘察期间坝基岩体结构面勘探这一难题,具有高效、直观、可靠的特点．通过孔内摄像,容易发现基坑中出露少的缓倾不利结构面．使用孔内摄像勘探坝基岩体结构面特征时,应注意“一孔之见”的局限性及岩体结构面在空间上的不均匀性．勘探时,一方面要保证有合适的孔内摄像点数量,另一方面要及时分析孔内摄像成果,判断岩体结构面的变化规律．     

海底管线的地球物理探测技术探讨

从应用原理、工程实例、应用效果等方面分析了目前国内外常用的海底管线探测的技术方法,并且探讨了各种方法的优缺点及适用条件,总结了海底管线探测现状及发展趋势.     

金塘大桥连续箱梁架设测量控制技术

结合金塘大桥预制连续箱梁架设施工的测量控制所遇到的问题,对连续箱梁架设的线性控制以及标高的控制技术,优化布点控制方案作一描述。     

Port Decision Maker Perceptions on the Effectiveness of Climate Adaptation Actions

Effective adaptation to climate change impacts is rapidly becoming an important research topic. Hitherto, the perceptions and attitudes of stakeholders on climate adaptation actions are under researched, partly due to the emphasis on physical and engineering aspects during the adaptation planning process. Building on such considerations, the paper explores the perceptions of port decision makers on the effectiveness of climate adaptation actions. The findings suggest that while port decision makers are aware of potential climate change impacts and feel that more adaptation actions should be undertaken, they are skeptical about their effectiveness and value. This is complemented by a regional analysis on the results, suggesting that more tailor-made adaptation measures suited to local circumstances should be developed. The study illustrates the complexity of climate adaptation planning and of involving port decision makers under the current planning paradigm.     

长江口水域高精度水文测量四维无缝基准的建立及应用

在宽阔的潮汐河段,由于潮汐和地形的影响,大范围的同步水文测验的精度和可靠性受到了很大的限制。为了得到高精度的水文测量成果,使同步观测资料和时间序列资料具备良好的可比性,需要建立高精度的平面基准、高程基准和速度基准。理论和实践表明,建立大范围内的高精度的GNSS(global navigation satellite system)控制网,基于RTK(real-time kinematic)测量方式进行三维水深测量、基于RTK的速度参考进行流量测量,是在大范围条件下开展高精度同步水文观测的有效途径。     

An investigation of tour generation models combining two waves of household travel surveys through pooled models

This paper presents a study that examines two waves of travel survey data through a pooled model structure. The pooled model structure provides a means to take advantage of multiple data sources which will lead to a better estimate and understanding of travel behavior. In particular, it accounts for the difference in data variance and therefore allows for the comparison of the true impacts of the model parameters on travelers’ tour-making behavior. Larger variance is found in the 1998 data than in the 2010 data. Comparison between model parameters reveals significant behavioral changes among several socio-economic and demographic groups. In terms of common variables, the magnitude of the coefficient values has generally decreased, which conforms to the overall decreasing trend in traveling. Overall, the model equality tests indicate that the models developed based on the two data sources do not have equal taste parameters, thus the transferability hypothesis is rejected. The results of this study are expected to have implications for the application of models based on cross-sectional data, especially over long time periods.     

浅谈3S技术在公路勘察设计中的应用

对3S技术及其发展状况进行了阐述,着重讨论了3S技术在公路勘察设计中的应用,为3S技术在交通领域的进一步推广应用提供参考。     

集OD调查交通分布径路选择于一体的调查方法

为了向城市交通规划提供更为精确、更为全面的基础资料,以确保交通规划的各项工作质量,使交通规划更切合城市的实际情况。在对传统的交通调查和交通规划方法进行分析的基础上,提出了一种新的调查方法,通过对各交通小区的驶出交通量进行着色调查和各路段交通量进行分类调查,并通过一定的内业整理,便得到更为全面的交通数据。