成都地铁土压平衡盾构隧道工程风险识别与评价

成都地铁一号线试验段区间隧道第一次采用土压平衡盾构施工。成都地层条件为富水的砂卵石地层,卵石含量高,盾构施工难度大,风险大。研究了工程的风险发生机理,找到了主要的工程风险,并采用R=P×C法对主要风险进行了评价和分级,确定了主要风险的风险级别,为工程的顺利进行提供了参考与保障。     

Modeling of individual vehicle safety and fuel consumption under comprehensive external conditions

This research intends to explore external factors affecting driving safety and fuel consumption, and build a risk and fuel consumption prediction model for individual drivers based on natural driving data. Based on 120 taxi drivers’ natural driving data during 4 months, driving behavior data under various conditions of the roadway, traffic, weather, and time of day are extracted. The driver's fuel consumption is directly collected by the on-board diagnostics (OBD) unit, and safety index is calculated based on Data Threshold Violations (DTV) and Phase Plane Analysis with Limits (PPAL) considering speed, longitudinal and lateral acceleration. By using a linear mixed model explaining the fixed effect of the external conditions and the random effect of the driver, the influences of various external factors on fuel consumption and safety are analyzed and discussed. The prediction model lays a foundation for drivers' fuel consumption and risk prediction in different external conditions, which could help improve individual driving behavior for the benefit of both fuel consumption and safety.     

Influence of driving patterns on vehicle emissions: A case study for Latin American cities

On-board real-time emission experiments were conducted on 78 light-duty vehicles in Bogota. Direct emissions of carbon monoxide (CO), carbon dioxide (CO₂), nitrogen oxides (NO_x) and hydrocarbons (HC) were measured. The relationship between such emissions and vehicle specific power (VSP) was established. The experimental matrix included both gasoline-powered and retrofit dual fuel (gasoline–natural gas) vehicles. The results confirm that VSP is an appropriate metric to obtain correlations between driving patterns and air pollutant emissions. Ninety-five percent of the time vehicles in Bogota operate in a VSP between −15.2 and 17.7 kW ton⁻¹, and 50% of the time they operate between −2.9 and 1.2 kW ton⁻¹, representing low engine-load and near-idling conditions, respectively. When engines are subjected to higher loads, pollutant emissions increase significantly. This demonstrates the relevance of reviewing smog check programs and command-and-control measures in Latin America, which are widely based on static (i.e., idling) emissions testing. The effect of different driving patterns on the city’s emissions inventory was determined using VSP and numerical simulations. For example, improving vehicle flow and reducing sudden and frequent accelerations could curb annual emissions in Bogota by up to 12% for CO₂, 13% for CO and HC, and 24% for NO_x. This also represents possible fuel consumption savings of between 35 and 85 million gallons per year and total potential economic benefits of up to 1400 million dollars per year.     

基于深度特征聚类的高排放移动污染源自动识别

传统的高排放移动源识别方式是将采集的尾气数据与预先设定的排放阈值进行比较判 定，但是，排放阈值的设定很大程度上取决于人为标准，并且忽视了外部因素对尾气排放的影响， 无法真正反映移动源排放水平。针对此问题，本文结合机器学习算法，提出一种基于深度特征聚 类的高排放移动源识别方法。首先，利用随机森林算法筛选出不同污染物(CO、HC、NO)排放的 主要影响特征；其次，对多维影响特征进行聚类分析，获取高排放类别标签；最后，训练得到基于 深度森林的移动污染源分类模型，自动识别高排放目标源。通过对比实验，在合肥市机动车污染 遥测数据集上验证了所提方法的有效性。     

基于l1范数稀疏解的水下双层圆柱壳振动声辐射预报影响因素研究

基于模态叠加法理论,采用l1范数稀疏解方法,实现了水下双层圆柱壳由内壳有限测点振速值重构得到内、外壳振速空间分布,进而基于边界元理论对结构水下辐射声场进行预报。通过数值计算,分析了模态数目、测点数目和模态振型误差等因素对振动声辐射预报结果的影响,为指导速度场重构时模态数目、测点数目的选取提供了一定的理论依据;结果表明基于l1范数稀疏解声学预报方法对模态振型误差有一定的鲁棒性。最后开展了水下典型双层圆柱壳结构振动声辐射预报的试验研究,可为工程领域结构的声振预报提供一定的指导思路。     

铁路工程的风险管理分析

铁路工程建设项目具有工程量大，建设工期长，投资巨大，容易受到不可抗拒因素和意外事故的影响，风险性大，风险不确定的特点。此文对铁路工程项目风险的特点、内容进行了介绍，给出了识别与决策的方法，对促进我国建设项目风险管理的研究和推广具有重大的现实意义。     

基于鲁棒二次稳定性理论的状态观测器增益矩阵求法

针对具有定子电阻不确定参数的电机模型，设计了全阶自适应状态观测器，运用具有定子电阻参数不确定系统的二次稳定性理论，推导出转子速度的自适应辨识率，同时将定子电阻和速度视作不确定参数，利用LMI工具箱中求解不确定参数系统二次稳定性的方法，得到状态观测器的增益矩阵来保证整个系统在全速度范围内的稳定运行。此方法计算量小，易满足实时性控制要求。仿真结果表明，基于鲁棒二次稳定性理论求出状态观测器增益矩阵能保证系统在全速度范围内的稳定运行，并且可抑制定子电阻不确定性对速度辨识的影响，具有很好的鲁棒性能。     

水工混凝土结构损伤识别软件的开发与应用

在水工混凝土结构损伤识别理论的基础上．利用多语言编程技术（C＋＋＆Fortran）开发了界面友好、使用方便的损伤识别软件。应用软件对理论模型和试验模型进行识别。得到了很好的识别结果。     

超高能γ射线与红外辐射光子的相互作用

本文通过对超高能γ射线与太阳系周围的氢云的红外辐射相互作用的讨论，说明考虑到氢云的不均匀性，如果氢云的红外辐射温度有３０Ｋ左右，氢云直径为１８０ｐａｒｓｅｃｓ，这种相互作用就可以用来解释近年来所发现的某些超高能γ射线点源信息缺乏的现象。     

PATERNITY IDENTIFICATION ON ABORTED FETAL MATERIAL

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