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在双碳目标背景下,隧道低碳施工方案优选成为一种迫切需求。在多属性决策综合评价体系基础上,对隧道施工过程在不同场景要求下的待评估稳定指标展开讨论,筛选出围岩稳定性、地层稳定性、支护稳定性3个因素,与非稳定性指标平行组构,着重考虑碳排放非稳定性因素,建立隧道低碳施工方案综合评价指标体系。基于支持向量机-多效用度函数法(Support Vector Machine-Multi-Attribute Utility Theory, SVM-MAUT)设计映射模型,以替换传统综合评价方法,探索低碳化隧道施工方案比选方法。将提出的比选方法应用于大凉山1号隧道破碎大变形软岩段施工方法优选,根据玄武岩段、黏土岩段和粉砂质泥岩段的方案效用度大小,选出最优方案组合,相较极端排放量该方案每延米分别减少2 313.01 kg、790.10 kg和717.84 kg的碳排放当量,隧道稳定性符合设计与规范要求,截面收敛变形均在设定控制值内。 相似文献
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城际铁路在国民经济和社会发展中发挥着重要作用,但在投资主体由"部省合作"向"地方主导"转变的过程中,出现了建设资金不足、资金筹措方式单一、可持续发展压力大等问题。本文通过对珠三角地区、京津冀地区、成渝地区等典型地区城际铁路建设投融资模式的调查研究,分析当前城际铁路投融资模式存在的主要问题,并研究提出相关的措施建议。 相似文献
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为准确、有效、综合地对极地航线运行风险进行分析和评估,提出了基于组合赋权-云模型的极地航线运行风险评价方法,并以G航空公司为例进行了实例分析。首先在研究极地航线运行特殊性的基础上构建极地航线运行风险评价指标体系;然后分别采用G1法与熵权法确定各项指标的主、客观权重,再结合最优数学模型确定组合权重;最后,利用云模型对极地航线运行风险进行评价。结果表明,一级指标中环境因素对航线运行安全的影响最大,二级指标中极地自然环境及通讯导航设备对航线运行安全的影响最大,该公司极地航线运行的风险等级介于“较低风险”与“极低风险”之间。基于组合赋权-云模型的极地航线运行风险评价方法能够有效发现极地运行中面临的问题,具有可行性。 相似文献
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我国铁路体制改革后城际铁路发展对策 总被引:1,自引:1,他引:0
本文分析研究我国城际铁路发展现状及发展趋势后,通过对我国铁路体制改革过程中城际铁路面临的主要问题进行剖析,提出我国城际铁路投融资、运营管理、票价管理、公益性补偿等方面的发展对策及政策建议。 相似文献
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针对损伤可识别性以及基于模态可观测性两大优化准则对多跨简支梁传感器布置适用性低的特点,本文提出了红柳至一里坪地方铁路桥梁基于层次分析法的加速度传感器的优化布置方法,分析了轨道接头位置、桥梁线形、桥墩高度、离0#桥台距离四种属性对结构振动响应以及投资成本两方面的影响,形成了从方案层、准则层到目标层三个层次的加速度传感器优化布置模型,结果表明,第2、5、7、8、15、16、18、21、25、28等桥跨在四种属性下权重最最大,故在这些桥跨布置加速度传感器。 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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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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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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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