新型塑料排水板性能试验及分析

塑料排水板是加固软基的一种复合排水材料.介绍新型塑料排水板的主要特性指标和滤膜的主要性能指标,通过室内试验从物理性能、力学性能和水力学等性能方面对滤膜的性能进行比较.     

金穗路浅埋式车行隧道设计

结合广州市珠江新城下穿中央林荫大道的车行隧道工程实践,介绍浅埋式车行隧道的结构设计、结构防水设计、基坑大开挖及地下水控制等施工工艺。     

城市轨道交通换乘站火灾报警系统设计

论述火灾报警系统(FAS)在城市轨道交通运营中的重要作用。对我国地铁设计中地铁换乘站FAS的设计进行分析,提出地铁换乘站FAS联动设计的思路,包括独立设计方案和延续设计方案。实践表明,这两种方案可有效地解决换乘站FAS系统间的火灾联动。     

我国电动汽车充换电基础设施标准的现状和发展建议

为了能够更加合理地制修订我国电动汽车充换电基础设施的相关标准,进一步促进电动汽 车推广应用目标的顺利实现,对我国现有的充换电基础设施相关标准开展了研究。首先,对国外 充换电基础设施标准概况和我国相关的主要国家标准、行业标准、地方标准和企业标准进行了介 绍;接着,对我国现有标准中关于充换电设备、充电接口及通信协议、充换电计量装置、充换电 站的相关规定进行了分类介绍,明确了现有标准对于确保电动汽车用户充换电体验质量的重要意 义;然后,针对电动汽车用户完整的充换电流程,对实际中用户存在的充换电服务需求进行了分 析;最后,根据用户的实际服务需求,提出了我国未来充换电基础设施标准的制修订建议。研究 结果表明,我国现有的充换电基础设施标准基本确保了充换电设备的可用性和易操作性、充电接 口的通用性、充电计量装置的准确度以及充换电站的运营安全等,未来应针对充换电设备状态查 询、直流充电桩的兼容性、统一支付、充换电站规模和布局等方面制定相关标准,以提高电动汽 车用户体验质量和促进电动汽车的进一步推广应用。     

Investigation of Occupant Lower Extremity Injures under Various Overlap Frontal Crashes

Objective

With widely usage of restraint system, fatal injuries to occupants have been largely limited while non-fatal lower extremity injuries have not been effectively improved. The present study aims to investigate occupant lower extremity injuries under realistic impact environments.

Methods

A biofidelic lower extremity model, a dummy model and a car cab model were combined to set up a realistic impact environment. Three typical frontal impact groups were simulated. Occupant global lower kinematics, long bone axial force and bending moment were presented to in-depth investigate lower extremity injury mechanism and tolerance.

Results

Various overlap frontal impacts cause totally different lower extremity kinematics in the combination of structural invasion and restraint system effects. The femur fracture occurred at a small axial force of 7.57 kN combing a substantial bending moment peak of 172 Nm. Ankle joint injuries were found in 100 % and 25 % overlap impacts that present large tibial axial force and joint rotation angle.

Conclusions

Overall results indicate that a coupling threshold of femur axial force and bending moment is of rationality to predict global femur fracture. The ankle joint injury occurrence is significantly related to the coupling effects of tibia axial force and excessive self-kinematics.

     

Technology application and development trend of intelligent unmanned system北大核心CSCD

Intelligent unmanned system combat is moving from concepts to actual combat applications. The military applications of intelligent unmanned systems are emphasized by focusing on the needs of the combat missions that they will undertake on future battlefields and summarizing the development statuses of land, air and maritime unmanned systems. Aiming at the key problems faced by intelligent unmanned systems and the practical difficulties that will be faced on the battlefield in the future, we analyze the key technologies required for intelligent unmanned systems, including autonomous perception and understanding in complex environments, behavioral decision-making and trajectory planning, autonomous navigation and positioning, multi-scenario autonomous skill learning and intelligent control, unmanned cluster cooperative control, natural human-computer interaction, etc. At the same time, aiming at the problems that will be encountered in the further development of intelligent unmanned systems on the battlefield in the future, we start with individual enhancement and cluster enhancement, and conduct a detailed analysis of the development trends of intelligent unmanned systems. © 2022 Palaeobulgarica. All rights reserved.     

基于蓝墨云班课的《汽车材料》课程优化与实施

随着“互联网+”时代的到来,移动互联网技术给教育领域带来重大的变革,充分合理地应用互联网技术能更好的推动技工院校课程教学改革。蓝墨云班课作为一种基于互联网技术的移动教学平台,将其应用于《汽车材料》课程教学中,能很好地形成线上和线下一体融合的教学模式,提高学生课堂参与度,打造生动、高效、一体的课程学习环境。     

预应力PHC管桩施工技木浅谈

预应力PHC管桩,作为软土地基上建筑基础主要型式,目前得到广泛的应用.该种基桩具有预制工厂化、质量可控制、加工速率高、单桩承载力高、桩身耐锤击性好、穿透力强、造价便宜等特点.以洋山中港区110kV开关站及降压站工程、消防站工程和管理楼工程的预应力PHC管桩施工为例,介绍了该工程地质情况,打桩前的准备工作和预应力PHC管桩施工技术工艺流程及技术措施.