利用CIVIL 3D进行海港工程疏浚设计方法研究

本文在南方某海港工程港池航道工程设计中引入BIM正向设计,利用CIVIL 3D建立了地形曲面和地质曲面模型,建立采样线,对地形曲面、设计曲面、地质曲面进行采样;用断面法进行疏浚工程量计算,用程序自带网格施工图及其他软件等多种方法进行校核以验证计算准确性;通过材质定义,计算不同土类疏浚量并在断面图中表示;在设计完成后,按...     

国际造船协定谈判缘何起起落落

2010年12月17日,经济合作与发展组织（OECD）造船工作组宣布,新一轮的国际造船协定谈判,因各方始终缺乏统一立场,难以达成共识而再次终结。回首这起历经20余年的＂跨世纪谈判＂,一幅各方利益博弈图跃然纸上。而这张博弈图,清晰地勾勒出了世界造船版图由西向东的变迁。     

An Optimization Model for Guiding Pedestrian–Vehicle Mixed Flows During an Emergency Evacuation

In most metropolitan areas, an emergency evacuation may require a potentially large number of pedestrians to walk some distance to access their passenger cars or resort to transit systems. In this process, the massive number of pedestrians may place a tremendous burden on vehicles in the roadway network, especially at critical intersections. Thus, the effective road enforcement of the vehicle and pedestrian flows and the proper coordination between these two flows at critical intersections during a multimodal evacuation process is a critical issue in evacuation planning. This article presents an integrated linear model for the design of optimized flow plans for massive mixed pedestrian–vehicle flows within an evacuation zone. The optimized flow can also be used to generate signal timing plans at critical intersections. In addition, the linear nature of the model can circumvent the computational burden to apply in large-scale networks. An illustrating example of the evacuation around the M&T Bank Stadium in downtown Baltimore, MD, is presented and used to demonstrate the model's capability to address the complex interactions between vehicle and pedestrian flows within an evacuation zone. Results of simulation experiments verify the applicability of our model to a real-world scenario and further indicate that accounting for such conflicting movements will yield more reliable estimation of an evacuation's required clearance time.     

Brittleness analysis and important nodes discovery in large time-evolving complex networks

The brittleness analysis and important nodes detection have been a hot spot in the complex networks. How to get the overall feature of the whole network and how to find out some important nodes are requisites to solve these problems. In this paper, we adopt the trace of the adjacency matrix and the centrality of the complex networks to give a quantitative and qualitative analysis of networks being studied. Results show that the k-shell plays a more important role than the degree centrality and the betweenness in finding important nodes, and it can also be used to give direction on the immunization and maintenance of complex networks.     

The effect of travel time variability on route choice decision: a generalized linear mixed model based analysis

The effect of travel time variability (TTV) on route choice behavior is explored in this study. A stated preference survey is conducted to collect behavioral data on Shanghai drivers’ choice between a slow but stable route and a fast but unreliable route. Travel time and TTV are respectively measured by mean and standard deviation of random travel time. The generalized linear mixed model (GLMM) is applied to quantify trade-offs between travel time and TTV. The GLMM based route choice model effectively accounts for correlations among repeated observations from the same respondent, and captures heterogeneity in drivers’ values of TTV. Model estimation results show that, female drivers and drivers with rich driving experience are less likely to choose a route with high TTV; smaller expected travel time of a route increase the probability of its being chosen; all drivers have intrinsic preference for a route with smaller expected travel time, but the degree of preference may vary within the population; TTV on average has negative effects on route choice decision, but a small portion of drivers are risk-prone to choose a fast but unreliable route despite high TTV.     

汽车被动安全性及碰撞仿真研究综述

介绍了为保证汽车的被动安全性实施的国家基本标准和社会自发制定的评价体系,分析了被动安全性的主要研究内容和方法,着重探讨了国内外利用计算机虚拟仿真技术进行的研究,基于现状,今后的研究方向是更精细化的仿真研究与实现仿真碰撞和实车碰撞的良好交互。     

W钢带补强隧道衬砌缺陷施工技术

以新建铁路贵阳枢纽白云至龙里北联络线龙洞堡机场隧道施工为例,详细介绍了隧道二次衬砌补强缺陷整治的原则、材料要求、方法及措施、施工工艺,重点阐述了嵌W钢带配碳纤维布整治隧道二衬缺陷的方法及工艺,对地下工程病害及缺陷整治可起到借鉴作用,对今后类似地下工程的施工具有一定的参考价值。     

砂岩隧道洞渣集料在宜巴高速公路中的应用

为探讨宜巴太阳岭砂岩洞渣用作混凝土集料的可行性,对母岩抗压饱和强度、物理化学成分、碱活性进行分析,采用简化砂、石联产工艺生产出砂岩碎石、机制砂并对其基本技术指标进行检测.研究表明,该砂岩洞渣为硬质砂岩,加工的碎石、机制砂可满足混凝土集料技术指标要求.以宜巴高速公路为依托,成功地将砂岩集料配制的混凝土应用于隧道二衬与桥梁桩基、墩柱.     

十载风雨 海事助推太仓古港新远航

这里,是六百多年前,郑和率船队七下西洋的起航地;这里,号称七百年前的"六国码头"、"天下第一码头"。这就是江苏太仓,位于长江三角洲冲积平原上,与崇明岛隔江相望,是长江入沪前的最后一道关口。2001年1月18日,江苏太仓海事处挂牌成立。自此,太仓海事人牢牢抓住国家加快内河航运发展,江苏