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101.
采用定性分析和数值分析方法,针对金鸡山隧道拓宽工程的难点问题,提出相应技术解决措施,并结合工程实践,运用监控量测实测数据进行验证,认为:金鸡山四车道隧道采用的二次支护的结构型式及其衬砌支护参数是安全合理的,结合控制爆破技术和相应的安全防护措施,设计采用的CRD法和CD法等施工方法能够满足安全施工的要求。 相似文献
102.
The aim of this study was to describe the crash characteristics and patient outcomes of a sample of patients admitted to hospital following bicycle crashes. Injured cyclists were recruited from the two major trauma services for the state of Victoria, Australia. Enrolled cyclists completed a structured interview, and injury details and patient outcomes were extracted from the Victorian State Trauma Registry (VSTR) and the Victorian Orthopaedic Trauma Outcomes Registry (VOTOR). 186 cyclists consented to participate in the study. Crashes commonly occurred during daylight hours and in clear weather conditions. Two-thirds of crashes occurred on-road (69%) and were a combination of single cyclist-only events (56%) and multi-vehicle crashes (44%). Of the multi-vehicle crashes, a motor vehicle was the most common impact partner (72%) and distinct pre-crash directional interactions were observed between the cyclist and motor vehicle. Nearly a quarter of on-road crashes occurred when the cyclist was in a marked bicycle lane. Of the 31% of crashes that were not on-road, 28 (15%) occurred on bicycle paths and 29 (16%) occurred in other locations. Crashes on bicycle paths commonly occurred on shared bicycle and pedestrian paths (83%) and did not involve another person or vehicle. Other crash locations included mountain bike trails (39%), BMX parks (21%) and footpaths (18%). While differences in impact partners and crash characteristics were observed between crashes occurring on-road, on bicycle paths and in other locations, injury patterns and severity were similar. Most cyclists had returned to work at 6 months post-injury, however only a third of participants reported a complete functional recovery. Further research is required to develop targeted countermeasures to address the risk factors identified in this study. 相似文献
103.
传统民居的开发利用有其独特的个性。赣州地区拥有丰富的自然资源和人文资源,具有发展旅游业的巨大潜力,应通过保护、改造、更新及功能置换等方式,实现传统民居保护和发展的协调发展。 相似文献
104.
本文对递推平滑滤波的原理及性能进行了分析,得到了滤波器截止频率与采样频率、滤波器队列长度的关系。将递推平滑滤波应用在通风机压力测试中,取得了较好的效果。 相似文献
105.
106.
107.
针对多种道路场景下车道线的识别问题,提出了一种应用匹配滤波器和恒虚警率检测器的处理方法。根据车道线横截面的灰度轮廓特征,对图像局部区域,采用不同尺度的匹配滤波算子,实现不同环境条件下车道线区域的特征增强;利用可产生自适应阈值的恒虚警率检测器,提取车道线特征点,并通过随机抽样一致性方法拟合产生车道边界线。在车道线跟踪阶段,建立车道线参数数据库,分析当前帧车道线与数据库的匹配置信度,并动态更新该数据库。在嵌入式系统中,经过多种工况的试验验证,该算法能稳定地识别车道线,准确提取相关参数,处理速率达到30FPS。 相似文献
108.
N.A. KISELEV A.S. KUMSKOV V.G. ZHIGALINA A.L. VASILIEV J. SLOAN N.S. FALALEEV N.I. VERBITSKIY A.A. ELISEEV 《Journal of microscopy》2016,262(1):92-101
HRTEM and HAADF STEM of 1DTbBrx@SWCNT meta‐nanotubes reveal three structural modifications of 1D nanocrystals within single wall carbon nanotube channels attributed to a different stoichiometry of the guest crystal. For SWCNTs with diameters Dm > 1.4 nm a most complete tetragonal unit cell is observed. When crystallization occurs inside SWCNT with Dm < 1.4 nm 1D TbBrx crystal deforms a nanotube to elliptical shape in cross section. In this case the 1D crystal unit cell becomes monoclinic, with possible loss of a part of bromine atoms. Two modifications of a monoclinic unit cell appear. One of them is characterized by single or pair vacancies in the structure of the 1D crystal. Another structure is explained by peripheral and central bromine atoms loss. An appearance of such modifications can be stimulated by electron irradiation. The loss of bromine atoms is in agreement with chemical analysis data. Electronic properties of obtained meta‐nanotubes are investigated using optical absorption and Raman spectroscopy. It is shown that intercalation of terbium bromide into SWCNTs leads to acceptor doping of SWCNTs. According to local EDX analysis and elemental mapping this doping can arise from significant stoichiometry change in 1D nanocrystal indicating an average Tb:Br atomic ratio of 1:2.8 ± 0.1. 相似文献
109.
在井下倾斜运输巷道的阻车器上,通过安装拉伸弹簧,实现了阻车器的常闭,大大提高了系统的安全性和可靠性,掘进巷道的工效和斜巷运输效率显著提高。 相似文献
110.
阐述了用动心辅助球面法求相贯线的原理和方法 ,说明了该方法不仅适用于回转面相交 ,而且对其中一个是非回转面 ,另一个曲面的截交线是圆的情况也适用。该法既适用于两轴线相交 ,也适用于轴线平行的情况 相似文献