H－120型防火防爆气动移门的设计及其在海洋平台上的应用

按照船级社近海工程入级规范要求,海洋作业平台危险区域处的封闭机械处所通常需要满足气密、海洋石油工业防火等级、防爆、风雨密、隔音等要求,甚至供作业人员进出的门也要满足此要求。目前,按照国内船舶标准制作的门,尚无法满足上述规范要求。该文根据“挪威NORSOK标准”和“DNV近海工程入级规范”,对H-120型防火防爆气动移门的设计进行研究,并结合实际项目给出了其在海洋平台危险区域机械处所的应用设想与具体方法,为国内同类产品生产厂家提供思路,从而更好地适应海洋工程的发展趋势。     

我国公路养护技术发展现状与对策

随着公路负荷的不断增加,各种人为因素和自然因素对公路造成的损害也日益加重。运用先进的公路养护技术,加强公路养护是一项重大的研究课题。鉴于此,在分析我国公路养护技术发展现状的基础上,探讨了稀浆封层、雾封层、微表处等一些具体的养护方法,可为相关公路养护提供参考。     

沥再生雾封层技术的研究及应用

路面沥青在自然和车辆荷载的作用下会导致沥青中的油分含量降低,沥青质和胶质含量增加,稠度变大,脆度增加;室内试验表明,室内190℃高温烘箱老化36 h沥青与上海地区使用年限为3～5年的沥青性能类似,3．3％掺量的沥再生能够有效地恢复甚至改善老化沥青的基本性能。实体工程试验段说明,沥再生雾封层预防性养护技术能够有效防止路面病害的发展,维持路面良好的抗滑性能。     

A study of the influence of severe environmental conditions on common traffic congestion features

On the basis of real traffic and environmental data measured on German freeways, we studied common features of traffic congestion under the influence of severe weather conditions. We have found that traffic features [J] and [S] defining traffic phases “wide moving jam” (J) and “synchronized flow” (S) in Kerner's three‐phase theory are indeed common spatiotemporal traffic features. The quantitative parameters for both traffic phases [S] and [J] were investigated in a comparison of “ideal” weather conditions (good visibility and no precipitation) and severe weather situations (icy road, wind, precipitation, etc.). We showed spatiotemporal congested patterns in several space–time diagrams based on the Automatic Tracking of Moving Jams/Forecasting of Traffic Objects (ASDA/FOTO) model reconstruction for roadside detectors. A statistical study of traffic phase [J] parameters was presented, showing the average values and standard deviation of the quantities. Similarities and differences were analyzed, and some consequences for vehicular applications were discussed to cope with severe weather conditions. Copyright © 2013 John Wiley & Sons, Ltd.     

雾天微弱激光回波信号增强与处理研究

研究了雾天多脉冲信号累积增强原理和方法,并利用多脉冲累积增强原理对激光回波信号进行处理。为了提取微弱激光回波信号的特征,研究了匹配滤波处理算法,并分别就原始回波信号和多脉冲累积增强信号进行了匹配滤波处理,大大提高了信号的信噪比。实验结果表明：4个独立激光回波信号进行累积处理的结果使得回波信号的信噪比增强了2倍;多脉冲累积可以有效地提高回波信号的信噪比,而匹配滤波在提高信号信噪比的同时抑制了噪声。     

日本来岛海峡航法

就日本来岛海峡的航法、潮流、雾况、通航情况及船过来岛海峡应注意的事项等进行了阐述,并结合航行来岛海峡的经验,指出了航行中应注意的问题。     

2006年雾对高速公路影响规律

高速公路雾天行车存在着严重的安全隐患,而且雾天交通安全也是一个世界性的问题。目前我国通行的做法是在雾天封闭交通,这样虽然避免了交通事故的发生,但是却以完全丧失高速公路的通行能力为代价。本文通过对2006年全国主要高速公路受雾影响预报的分析,得出全国范围内各地雾发生频率,主要高速公路受雾影响特征及各路段影响频率,总结出雾对高速公路的影响规律。为今后雾天气下全国高速公路交通气象预报提供参考和指导,为驾驶员雾天行车的安全性提供保障,并为高速公路管理部门在日常工作中,重点监控雾的频发路段,有针对性采取有效地管控措施提供依据。     

长江口水域航行安全探讨

本文将长江口水域有关水文气象、助航标志和船舶交通管理规定等做一总结介绍,并结合二起事故案例分析,探讨船舶在此水域的航行安全管理,以利航经长江口水域船舶的安全。     

复杂条件下高滩守护工程岸坡渗流破坏影响因素

针对荆江河段岸坡渗流破坏情况,结合破坏案例分析岸坡渗流破坏原因,确定岸坡渗流破坏主要影响因素——地质因素、水文因素和降水因素。荆江河段岸坡地质结构主要分为3类,即单一砂性土地质结构、上黏性土下砂性土双层地质结构以及由黏性土和砂性土组成的互层、夹层等结构土体。荆江河段地下水和江水补给关系复杂——汛期江水补给地下水,枯水期地下水补给江水。三峡蓄水后,汛后退水速度进一步加快,地下水和江水之间的渗流坡降进一步增加。荆江河段强降水天气分布出现频次和范围仍较高。在此基础上,进一步揭示高滩守护工程区域岸坡渗流破坏机理。     

Estimating freeway route travel time distributions with consideration to time‐of‐day,inclement weather,and traffic incidents

This paper develops an efficient probabilistic model for estimating route travel time variability, incorporating factors of time‐of‐day, inclement weather, and traffic incidents. Estimating the route travel time distribution from historical link travel time data is challenging owing to the interactions among upstream and downstream links. Upon creating conditional probability function for each link travel time, we applied Monte Carlo simulation to estimate the total travel time from origin to destination. A numerical example of three alternative routes in the City of Buffalo shows several implications. The study found that weather conditions, except for snow, incur minor impact on off‐peak and weekend travel time, whereas peak travel times suffer great variations under different weather conditions. On top of that, inclement weather exacerbates route travel time reliability, even when mean travel time increases moderately. The computation time of the proposed model is linearly correlated to the number of links in a route. Therefore, this model can be used to obtain all the origin to destination travel time distributions in an urban region. Further, this study also validates the well‐known near‐linear relation between the standard deviation of travel time per unit distance and the corresponding mean value under different weather conditions. Copyright © 2016 John Wiley & Sons, Ltd.