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隧道衬砌施工缝和沉降缝的止水带施工工艺,是目前防排水施工中的一大难点.文章对止水带连接方式、连接强度和止水带顺直、埋入深度、外露高度等的固定和保护进行探讨,并提出无钢筋衬砌段和钢筋衬砌段的止水带施工工艺,消除了止水带施工通病,可为隧道工程的止水带施工提供借鉴. 相似文献
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结合工程实践,介绍了钢筋冷挤压机械连接技术的原理、性能、施工准备、控制措施、技术要求和现场验收方法. 相似文献
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公路、建筑行业中,钢筋是最常使用的建材之一,因此,钢筋的连接技术也成了关注的问题之一,钢筋的连接方式和连接质量直接关系到建筑安全。通过对比分析常见的钢筋机械连接以及钢筋焊接技术的优、缺点,为钢筋连接方式的选择提供了一些建议。 相似文献
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文章介绍了柳州市辖区范围内的航道、船闸及港口码头等现有水运基础设施的基本情况,分析了柳州市水运发展持续低迷的原因,并从加快柳江红花至石龙三江口Ⅱ级航道工程、大藤峡二三线船闸工程及"翻坝运输"、启动招商引资、加大人才培养等方面探讨了推动柳州市水运市场蓬勃发展的对策. 相似文献
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Pedestrians as compared to vehicular traffic enjoy a high degree freedom of movement even in heavily congested areas. Consequently, there are more alternative links available to pedestrians between a given origin‐destination (O‐D) pair. This paper describes a study done by the University of Calgary to evaluate the factors affecting the choice of route on intra‐CBD trips or trips within the Central Business District (CBD). An origin destination survey conducted in downtown Calgary, Alberta enabled the identification of the most significant factors influencing the choice. These factors were analyzed in relation to the physical characteristics of the location, personal characteristics of the trip maker and the type of the trip. It appears that most people chose the shortest link and factors such as the level of congestion, safety or visual attractions were only secondary. This suggests that the length should be made a major consideration when planning and designing pedestrian links. 相似文献
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This paper estimates the efficiencies and productivity changes of 12 international airports in the Asia-Pacific region based on data from 1998 to 2006. We apply stochastic frontier analysis (SFA) to compute efficiency estimates and use the Malmquist productivity index (MPI) to analyze productivity changes. We use the SFA model with a translog-type production function after testing the statistical hypotheses. According to the results of the SFA hypothesis tests, airports have experienced a technological regression; the deviations from the efficiency frontier are caused more by technical inefficiency than random noise. However, the inefficiency was found to decrease. The MPI reveals a declining trend resulting more from technological change than from efficiency change, with a decrease in inefficiency. Taken together, both the hypothesis tests and the MPI not only provide consistent conclusions, but also suggest that airports should concentrate on technological progress. 相似文献
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介绍了城市轨道交通工程中杂散电流不同的监测系统的构成,分析了集中式、分散式和智能型等监测系统的配置和功能,以及智能型实时在线监测系统的重要意义,为轨道交通工程杂散电流监测系统的选择与应用提供参考。 相似文献
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明确埋地管道防腐保温层的技术评价标准,对埋地钢质管道的安全运行,延长管道使用寿命具有重要意义。为了对埋地管道防腐保温层做出有效评价,从间接检测与开挖检测2个方面,结合现场检测数据,提出了基于防腐保温层的电流衰减率、绝缘电阻率、质量状况与厚度的分级评价标准及基于4种评价指标的综合评判方法。工程实践表明,该评价标准对防腐保温层是否存在失效能做出有效判断。 相似文献
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天然气自动计量系统有多种组态软件,由于软件的不相通性,造成了计量系统数据采集的通用性差、数据传输与入库的时效性差、数据利用的可靠性低.结合各组态软件的实际情况,从设计上充分利用Oracle大数据处理能力以及Partition(分区表)的特性,实现历史数据的存储,应用WebService与COM+数据访问组件提供多层数据访问架构,采用OPC与DDE工业数据交换协议,实现了各站场计量数据的实时上传,为连续数据采集和实时监控提供了可能,节约了改造成本. 相似文献
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Joseph N. Prashker 《Transportation》1979,8(4):329-346
Reliability of travel modes was found to be the most important characteristic of transportation systems in several attitudinal investigations of individual travel behavior. This paper represents the first part of a research effort aimed at gaining a better understanding of the characteristics of reliability of transportation modes in urban travel. In this research, reliability characteristics are identified; their importance relative to each other is assessed, and an insight into possible structure of an objective reliability index is discussed. The research is based on perceived values of reliability, which were identified through a large attitudinal survey conducted in the Chicago metropolitan area. 相似文献