汽车正面碰撞后排小体位假人伤害研究及优化

提出了一种相应的伤害优化方案,基于 C-NACP正面碰撞工况搭建碰撞分析模型,同时通过与正面 100% 重叠刚性壁障碰撞试验的 Hybrid Ⅱ 5th女性假人试验数据进行对比来验证模型的可靠性。基于对标结果进行优化设计,对比分析不同优化方案对乘员安全性的影响趋势。确定优化方案,即增加碰撞锁止锁舌、线性预紧器配置,增加座椅刚度,调整安全带限力值。与原始方案相比,在碰撞过程中后排女性假人总体得分提升84%。根据C-NCAP星级评定规程,此后排女性假人得分高于94%,成绩优秀,验证了方案的有效性,可为后排小体位假人伤害的优化研究提供参考。     

Pedestrian detection for traffic safety based on Accumulate Binary Haar features and improved deep belief network algorithm

ABSTRACT

In order to improve traffic safety and protect pedestrians, an improved and efficient pedestrian detection method for auto driver assistance systems is proposed. Firstly, an improved Accumulate Binary Haar (ABH) feature extraction algorithm is proposed. In this novel feature, Haar features keep only the ordinal relationship named by binary Haar features. Then, the feature brings in the idea of a Local Binary Pattern (LBP), assembling several neighboring binary Haar features to improve discriminating power and reduce the effect of illumination. Next, a pedestrian classification method based on an improved deep belief network (DBN) classification algorithm is proposed. An improved method of input is constructed using a Restricted Bolzmann Machine (RBM) with T distribution function visible layer nodes, which can convert information on pedestrian features to a Bernoulli distribution, and the Bernoulli distribution can then be used for recognition. In addition, a middle layer of the RBM structure is created, which achieves data transfer between the hidden layer structure and keeps the key information. Finally, the cost-sensitive Support Vector Machine (SVM) classifier is used for the output of the classifier, which could address the class-imbalance problem. Extensive experiments show that the improved DBN pedestrian detection method is better than other shallow classic algorithms, and the proposed method is effective and sufficiently feasible for pedestrian detection in complex urban environments.     

Protection of Critical Waterborne Transport Infrastructures: An Economic Review

It is essential that transport infrastructures are protected against events which cause their failure. At an optimal level of protection, the sum of protection costs and expected residual damages following from disruptions will be minimized. In most cases however, this optimal level is not achieved because infrastructure protection is susceptible to various market and government failures. This brings us to the question who (a private or public actor) should do how much (the level of protection and intervention). This question is addressed in the present paper.

The starting point of the paper is the Directive of the European Council on the identification and designation of European Critical Infrastructures. We review the protection of critical waterborne transport infrastructures from an economic perspective. The review is based on a literature study and several interviews with Critical Infrastructure experts. For the studied infrastructures, we have identified causes and effects of their failure and examined the private–public roles in protecting them. Considering the market and government failures which occur in such configuration of roles, we propose several changes. We conclude that from a national policy perspective there are two important routes: (1) reinforcement of private sector roles among others by defining liabilities and providing information on risks and (2) strengthening of supra-national collaboration via improving and standardizing regulations, cost-sharing initiatives and penalty systems.     

中低速磁浮与轮轨交通系统电磁环境影响差异性分析

通过对中低速磁浮和轮轨交通系统的电磁发射实测数据进行深入分析,比较两者电磁参量典型数例和变化规律,得出了中低速磁浮线路和轮轨交通系统实测电磁参量在频域、时域和空间分布等方面的差异。该成果可为中低速磁浮相关标准制定和电磁干扰防护设计提供实测依据和技术支撑。     

平潭海峡公铁两用大桥航道桥基础设计与施工创新技术

平潭海峡公铁两用大桥为国内第一座跨海峡公铁两用大桥,桥址海域风大、浪高、水深、流急、潮汐显著,且岩面倾斜起伏大、裸岩硬岩分布广,气象水文及地质条件均十分复杂,尤其是桥址海域波流力巨大,为桥梁下部结构设计和施工带来前所未有的困难。为解决风浪作用和通航船撞力作用,3座大跨度通航孔斜拉桥在基础设计和施工中采用多项创新技术,首次选用4.5 m的钻孔桩;为解决复杂海域大直径钻孔桩难题,研发了KTY5000型动力头钻机和相关配套的打桩设备;为克服波浪力作用,部分深水裸岩区域采用导管架辅助建立施工平台;为适应桥位独特的海洋环境,3座大跨度通航孔斜拉桥主塔墩承台均采用圆端哑铃形高桩承台,承台顶露出高潮位以上,承台施工采用集主体防撞结构与施工围堰一体的防撞箱围堰结构,永久结构与临时结构相结合,节约材料的同时降低了施工的安全风险性。其大型防撞箱围堰采用工厂整体制造、整体吊装、整体下放,实现模块化、标准化施工,哑铃形承台系梁范围采用无封底混凝土施工创新技术。     

地铁杂散电流对埋地金属管道阴极保护的影响

运用有限元分析软件ANSYS建立了走行轨-大地-金属管道的有限元模型。通过改变走行轨回流、走行轨纵向电阻、土壤电阻率、走行轨与金属管道间距大小,模拟杂散电流的影响,模拟结果表明:走行轨回流越小、土壤电阻率越大、走行轨与管道间距越小对阴极保护电位的影响越小;当走行轨电压载荷为80 V、走行轨与金属管道间距为20 m时,杂散电流无法使金属管道阴极保护电位偏离正常范围。     

直流牵引供电系统钢轨电位限值问题及其治理方案

阐述了钢轨电位过高的原因及危害,对国内外相关标准中关于钢轨电位限值和最大允许接触电压的合理性进行了分析;探讨了钢轨电位限制装置保护、电压型框架保护、人体耐受电压限值三者之间的匹配关系。总结了钢轨电位过高的治理方法及今后的改进方向。     

一种新型通信基站方案介绍

介绍一种包括铁塔和机房在内的新型通信基站方案,可满足我国目前大力发展的高速铁路通信信号传输要求,同时解决了各移动运营商在同一个基站上实现共建、共享的技术难题,有助于工信部提出的电信基础设施共建共享方针的贯彻实施。本通信基站还具有外形美观、防盗、占地小、环保节能等优点。     

城市轨道交通的非传统安全威胁及技术防范

近年来,针对城市轨道交通的恐怖袭击事件或灾难事件屡有发生,其公共安全已引起社会的高度关注.通过对安全概念和非传统安全特点的分析,认为城市轨道交通的公共开放性、高密度乘客流和系统的封闭性使其成为最易受到威胁和袭击的目标.提出非传统安全已经成为城市轨道交通公共安全首要任务,重点是应对恐怖主义及严重的暴力犯罪行为.从恐怖威胁类型、保护对象、防范区域出发,根据"事先发现得了"、"事中控制得住"、"事后交得出人"的防范目标,运用威慑、监控、威胁最小化、响应和恢复策略,提出整体的防范技术系统构架;并探讨了探测和检测系统、访问控制系统的构成,以及安全防范技术设计的原则和目标.     

盾构法施工的环境保护技术

结合上海近年来在城市软土密集区盾构穿越施工的实践,对盾构穿越危险房屋、上方及下方穿越运营地铁的施工风险,以及变形控制标准与预测分析方法、土压力、注浆等关键施工工序及参数的控制细节进行了阐述和总结.明确提出:严格的地层损失率限制标准及强有力的监控手段,是化解盾构施工中各种风险的根本;针对特殊地质及环境条件下的盾构设备选型及相关工艺水平的改进与提高,是控制风险的决定性条件.