隧道内横向偏置火源火灾烟气温度特性全尺寸试验研究

为了研究隧道内火灾温度分布规律和烟气运动状态,使交通隧道火灾灾害降到最低,通过全尺寸隧道火灾试验研究了热释放速率为30 MW火源位于偏离横向中心位置一个车道宽度条件下的顶棚射流的烟气温度特征,分析了烟气在各阶段的温度分布以及沿横向和纵向扩散的规律。结果表明：在火源下游一定区域内,偏置火源火灾产生的烟气在沿隧道横向和纵向扩散温度分布均呈非对称形态;烟气继续沿纵向扩散一段距离后,逐渐出现和形成温度分层;偏置火源顶棚射流的温升趋势随时间呈二次多项式关系增长,远壁面烟气沉降高度和温度衰减幅值大于相应中心火源的试验值;与中心火源的相似,火源在下游30 m内的顶棚射流温升随纵向距离的增加符合指数衰减规律,但同时还受到偏置距离的影响;可使用量纲一的偏距与量纲一的纵向距离的函数关系式描述其分布规律。     

手机社交娱乐操作对驾驶人视觉参数影响研究

为探究手机社交娱乐操作对驾驶人视觉参数的影响,基于模拟驾驶器和SmartEye 眼动仪设计模拟驾驶实验,采集驾驶人正常驾驶、拨打电话、收发信息等5种操作下视觉特征数据,应用拉依达准则和联合频数分布直方图进行数据归约.针对不同操作下视觉参数,应用箱形图和Kruskal-Wallis显著性检验,验证视觉参数评价指标的有效性.结果表明：随手机操作类型的不同,驾驶人水平和垂直视角标准差、视线离开道路时间百分比、扫视平均速度和眨眼持续时间呈显著性变化,可作为视觉参数影响的评价指标;观看视频和刷朋友圈操作对驾驶人视觉影响程度明显高于拨打电话和收发短信操作.     

柴油机增压器包覆层隔声性能试验分析及优化设计

提出一种船用增压器的包覆层结构,其内层为绝热材料和吸声材料,外层为金属薄片。采用统计能量法(SEA)建立该结构的中高频段隔声数值模型,开展包覆层的隔声试验,隔声量实测值与仿真结果吻合较好,能验证数值建模的有效性。对包覆层的吸声材料的厚度、密度和流阻等参数进行优化设计,利用正交试验法设计数值试验组,采用极差和方差分析法分析影响材料隔声性能的关键因素,得出最重要的影响因素是材料厚度,在选型设计中还应考虑密度和流阻因素。当安装厚度受限时,可通过改变密度和流阻值来提高材料的隔声量。     

Eco-driving behaviors of electric vehicle users: A survey study

Previous research has shown that electric vehicle (EV) users could behave differently compared to internal combustion engine vehicle (ICEV) drivers due to their consciousness or practices of eco-driving, but very limited research has fully investigated this assumption. This research explores this topic through investigating EV drivers’ eco-driving behaviors and motivations. We first conducted a questionnaire survey on EV drivers’ driving behavior and some hypothetical decisions of their driving. It indicates various characteristics between EV and ICEV commuters, including self-reported daily driving habits, preferences of route choices, tradeoff between travel time and energy saving, and adoption of in-vehicle display (IVD) technologies. Then, through statistical analysis with Fisher’s exact test and Mann-Whitney U test, this research reveals that, compared to ICEV drivers, EV drivers possess significantly calmer driving maneuvers and more fuel-efficient driving habits such as trip chaining. The survey data also show that EV drivers are much more willing to save energy in compensation of travel time. Furthermore, the survey data indicate that EV drivers are more willing to adopt eco-friendly IVD technologies. All these findings are expected to improve the understanding of some unique behavior found in EV drivers.     

F型与直壁型护栏在客车撞击下的仿真研究

为了对比研究A类防撞等级中F型混凝土护栏和直壁型混凝土护栏的防护性能,建立两种护栏与客车的有限元模型,运用ANSYS Workbench软件中显式动力学模块,控制仿真碰撞的试验参数,将大客车模型以规定的初速度和碰撞角度进行计算机仿真碰撞试验,从车辆的加速度、车辆运行轨迹、护栏的最大动态变形量等方面综合对比两种护栏的防护性能。结果表明:相比直壁式护栏,F型混凝土护栏防撞性能、安全性能、导向性能较好。     

基于视频亚像素模板匹配算法的索力试验

针对索结构的索力测试,基于室内试验对比了计算机视觉方法和传统加速度传感器方法,探讨了计算机视觉方法的适用性。研究采用伺服静载锚固试验机张拉单根斜拉索钢绞线,简化模拟索张拉受力状态,通过相机摄影的非接触测量方法测量拉索动态响应,结合亚像素模板匹配算法识别拉索动态变形、基频和索力,并与传统的加速度传感器测试结果进行对比。研究结果表明,计算机视觉方法识别的拉索振动频谱峰值明显,基频识别结果与加速度传感器测试结果基本一致,索力识别结果与实测值相比最大误差不超过6%,具备开展实际结构索力测试的能力。     

多用途乘用车侧翻稳定性能动态测试方法研究

对比分析了国内外车辆侧翻稳定性相关的标准法规的基本情况。研究了车辆发生侧翻的类型和机理,基于侧向加速度判断车辆侧翻状态的方法,通过整车道路试验对比了正弦停滞试验和鱼钩试验诱导车辆发生侧翻的效果,初步探讨了多用途乘用车侧翻稳定性动态测试方法和评价指标,为国内车辆侧翻稳定系统的开发和测评标准的制定提供了参考。     

Experimental study on seismic vibration control of an offshore wind turbine with TMD considering soil liquefaction effect

Wind energy is clean and sustainable. Taiwan is establishing offshore wind farms using wind turbines in the Taiwan Strait. However, these are located in an earthquake-prone area with sandy seabed conditions. To ensure their safety and reliability, the turbines’ support structure must be protected against wind, waves, and seismic loads. Tuned mass dampers (TMDs) are commonly employed to reduce structural vibrations. A TMD is more simply incorporated into turbine structures than are other energy dissipation devices. In this study, a 1:25-scale test model with a TMD was constructed and subjected to shaking table tests to experimentally simulate the dynamic behavior of a typical 5-MW wind turbine with a jacket-type support structure and pile foundation. The scaled-down wind turbine model has a nacelle without rotating blades; therefore, the aerodynamic and rotational effects due to the rotating blades were ignored in this study. A large laminar shear box filled with saturated sandy ground was used to simulate the typical seabed conditions of Taiwanese offshore wind farms. The TMD system was designed to be tuned the first-mode frequency of the test model. Two ground accelerations, selected by considering wind farm site condition and near-fault characteristics, were used for excitation in the test. The responses of the test model with and without the TMD system were compared, and the influence of soil liquefaction on the effectiveness of TMD vibration control was addressed.     

天津港某翻车机房水文地质条件及基坑地下水控制方案探讨

本文通过野外钻探、现场抽水试验及室内试验等综合方法研究了天津港某翻车机房工程水文地质条件,对基坑地下水控制方案进行了探讨。     

冲击载荷下弹性索波动行为试验装置设计

针对在冲击波作用下难以对弹性索波动行为进行试验研究且实际试验成本高等问题,提出一种冲击载荷下弹性索波动行为试验装置,装置由加速系统、钢索系统及测试系统组成。根据总体性能要求,探索波动行为特征,确定各部分组成的工作原理和详细构成（载荷和系统等多种参数可以调整）,设计相关性能试验验证方法。试验装置在设计的过程中涉及试验原理的选择、试验方法的实现,以及信号处理和图像处理等技术,可为研究钢索应力波行为提供试验基础平台,也可为钢索应力波相关工程应用领域提供技术参考。