Response of the Black Sea mean level to atmospheric pressure and wind forcing

The response of the Black Sea mean level to atmospheric pressure (AP) and wind forcing is investigated using 5 years of TOPEX/POSEIDON (T/P hereafter) data. A coherence analysis is first applied to mean sea level and pressure to examine the validity of the inverse barometer (IB) approximation over this area. As expected, it reveals very significant deviations from an IB response attributed to the narrowness of the Bosphorus Strait and its limiting role in water exchanges. A comparison is drawn with the Mediterranean Sea case. A single basin version of the Candela analytical model [Candela, J., 1991. The Gibraltar Strait and its role in the dynamics of the Mediterranean Sea. Dyn. Atmos. Oceans 15, 267–300], which takes linear friction at the strait into account, is then used. The model explains a significant part of the T/P mean sea level variance (about 30%, while the IB correction only explains 5% of its variance) and provides a means to correct the altimeter data for the pressure effect much better than the standard IB effect. The response of the mean sea level to wind forcing is then analysed. Coherence analysis between sea level and along-strait wind stress (WS) reveals a significant coherence at periods ranging from 40 to 100 days, with an almost steady phase of 270°. This result is confirmed with a multiple coherence analysis (mean sea level vs. WS and AP). A plausible mechanism is a piling-up of water at the northern or southern end of the strait due to along-strait wind forcing. The associated along-strait pressure gradient would modify the barotropic flow in the strait and then the mean sea level. Using an extension of the Candela model, we show that this mechanism is consistent with T/P mean sea level observations.     

浅议现代玻璃幕墙建筑光污染

着重探讨现代玻璃幕墙建筑构成光污染的成因，通过对玻璃幕墙建筑的光照分析，探讨解决光污染的有效方法和应采取的相应措施。     

消除“红灯等待”焦急心理的安全措施及可行性分析

针对许多十字路口红灯设置时间过长、超出人们能够耐心等待的限度这一实际问题,研究一种能够有效消除人们等待焦急感的信息系统,对解决行人闯红灯的难题具有较强的实际意义。     

工业海洋大气环境下焊接耐候钢Q355NHD腐蚀后力学性能研究

随着钢结构桥梁建设需求不断提高、应用日益广泛,耐候钢以其优良的耐候性能,从材料层面为钢桥防腐提供了一种理想方案;但是,由于中国应用耐候钢的时间较短,耐候钢在某些自然环境下的适用性尚未得到充分论证,对其腐蚀后基本力学性能和疲劳性能的认识尚不完善。为此,以钢桥常用的Q355NHD焊接耐候钢及其对接焊缝为研究对象,针对中国滨海城市常见的工业海洋大气环境,通过周期浸润加速腐蚀试验探讨Q355NHD的耐候性能,并对腐蚀后Q355NHD的单调拉伸性能和疲劳性能开展试验研究。基于形貌观察、基体扫描、锈层分析和腐蚀深度计算等多角度分析,发现在模拟工业海洋大气环境下,Q355NHD尽管会形成具有一定致密性的锈层,但其腐蚀速率等宏观指标相比于普通钢并不突出。腐蚀后单调拉伸试验结果表明:腐蚀8周(等效于青岛受工业污染的海洋大气环境下自然腐蚀20年)后Q355NHD母材试件的屈服强度和抗拉强度分别下降8.1%和7.2%,对接焊缝试件的屈服强度和抗拉强度分别下降14.1%和12.5%。腐蚀后疲劳试验结果表明:腐蚀8周后Q355NHD母材试件和对接焊缝试件的设计疲劳强度分别下降35.6%和30.3%,为317.9 MPa和211.0 MPa,但仍然满足《钢结构设计标准》(GB 50017-2017)中相应构造类别的疲劳设计要求。经与既有文献报道的Q355普通钢试验结果对比,表明尽管Q355NHD在工业海洋大气环境中未表现出良好的耐腐蚀性能,不建议按免涂装使用,但其力学性能在不同批次试验结果中处于较高水平,可以视为一种优质的Q355钢材。     

Brake light cellular automaton model with advanced randomization for traffic breakdown

Traffic breakdown is one of the most important empirical phenomena in traffic flow theory. Unfortunately, it cannot be simulated by many traffic flow models. In order to clarify its mechanism, the new brake light cellular automaton model has been proposed. Comparing with previous brake light models, three different aspects have been considered: (i) drivers tend to take large decelerations if the time gap is smaller than the safe time gap and the leading vehicle’s brake light is on; (ii) the brake light rule is set according to the reality; (iii) the randomization rule is put forward before the acceleration rule to weaken the impact of brake light on driving behaviors. Analyses show that the new model can explain the mechanism of traffic breakdown and the failures of other brake light models. Simulations confirm that all empirical features of traffic breakdown are successfully reproduced. At last, brake light models are calibrated and validated by the I-80 empirical data provided by NGSIM. Results show that the performance of the new model is the best and models in the three-phase theory are not necessarily better than models in the fundamental diagram approach and vice versa, at least for the brake light models.     

基于Ecotect的T型交叉路口布灯方式仿真分析

为研究灯具布置对T型交叉口的照明影响,通过采用照明仿真软件对T型交叉口的交错式、对称式及中心对称式3种布灯方案进行仿真模拟分析,得到了不同布灯方式下的照明强度。结果表明:在相同灯具及条件下,交错式布灯方案最优,但道路终端灯光光强设置需偏大;对称式方案效果次之,交叉口中心位置照度低;中心对称式集中照明效果最好,但相比交错式及对称试其经济能耗最大。通过照明仿真模拟分析,有效验证了交错式布灯方案在T型交叉口照明设计中的优越性。     

复合地层大直径泥水盾构滚齿刀常压更换技术研究

泥水盾构在掘进过程中,由于受到环境条件有限、地质条件差、水土压力高、地层复杂多变等多种因素的影响,如何安全高效地更换滚刀和齿刀一直是盾构施工所面临的工程难题。本文提出一种高水土压力条件下滚刀、齿刀常压更换技术,介绍该技术的工作原理和作业要点,并以武汉地铁8号线越江隧道工程为例,针对越江隧道江中段的上软下岩复合地层以及工程所面临的特有工程难点,详细阐述滚刀、齿刀常压更换技术的具体操作步骤及其技术优势。通过采用该技术,有效提高了换刀效率,降低了安全风险,确保了施工的顺利进行。     

摩托车轻合金车轮径向冲击试验数据分析

摩托车轻合金车轮质量的好坏直接关系到摩托车骑乘者的人身安全,而摩托车轻合金车轮的径向冲击试验结果直接反映了车轮质量的优劣。通过对车轮径向冲击试验数据进行分析,以对车轮额定载荷的设定提出建议,希望摩托车整车企业及车轮生产企业合理设计轻合金车轮的额定载荷。     

深圳市红桂路-洒布路钢箱梁桥面铺装层材料设计及施工工艺研究

该文针对深圳市红桂路-洒布路钢箱梁桥的使用环境条件及路面特点,提出一种新型钢桥面铺装结构设计方案。并提出材料技术要求、施工工艺流程和施工质量控制等技术要点。     

基于CAN的无触点车灯开关控制系统研究与实现

应用CAN和霍尔元件设计了无触点式车灯组合开关控制系统。与传统的接触式开关系统相比,基于霍尔元件的无触点开关具有速度快、无机械磨损、无瞬问抖动、安全可靠以及寿命长等优点;与传统的开关控制系统相比,基于CAN的数字化开关控制系统具有节约安装成本、易于维护、可靠性高以及稳定性好的特点。通过搭建系统的硬件平台和设计车灯组合开关控制系统的控制软件,并进行实验,实验结果表明,提出的设计及实现方法是可行的。