张靖皋长江大桥锚碇基础地下连续墙施工技术

张靖皋长江大桥起自如皋市石庄镇焦庄村东侧,上跨S336,经石庄工业园东北、如皋港东升石材产业园东侧,路线转向南偏东,后于如皋华泰重工厂区架桥,采用主跨1 208 m双塔悬索桥跨越福北水道,进入如皋中汊。该悬索桥南锚碇位于长江江心岛上,基础采用圆形地下连续墙结构。地下水位受长江水潮汐影响明显,时刻不断地随潮位变化,下水位峰值较长江水位滞后约1～1.5 h,对地下连续墙施工影响较大,如何控制成槽及清孔质量、钢筋笼吊装是施工成功的关键。同时,成槽泥浆处理也是制约整个项目的关键工序。通过介绍张靖皋长江大桥工程概况、地下连续墙施工、泥浆处理和质量通病预防措施,并对地下连续墙槽段进行超声波检测。结果表明,所有墙体和接缝质量良好,均为Ⅰ类桩。     

某车型尾灯与侧围外板间隙面差匹配问题的优化

尾灯与侧围外板间隙面差匹配状态,影响消费者对整车外观的直接感知,本文通过优化尾灯、D柱焊合件、焊接工装,解决尾灯与侧围外板间隙面差匹配问题,在此基础上提出对关键零件关键安装配合区域增加功能尺寸控制要求,供后续项目参考.     

中国城市轨道交通安全问题及对策研究

通过分析我国当前城市轨道交通存在的问题及采取的安全监管措施,进而提出解决轨道交通建设、运营安全管理问题的长效机制。     

车站系统中的安全问题及其防范和恢复措施

对车站系统中存在的安全隐患做了分类介绍,并且针对这些隐患,提出了一些防范措施.     

对施工船舶安全监管的思考

文中从施工船舶安全现状入手,通过分析安全形势、存在问题及根源,提出解决问题的对策。     

MMAS在带时间窗的车辆路线问题中的应用

针对基本蚁群优化算法在物流配送路径优化应用过程中存在的问题,主要是由信息素全局和局部更新策略而导致车辆选择路径时容易陷入局部最优解的现象,本文详细研究了蚁群算法的改进算法,即最大最小蚁群算法;并引入信息素平滑机制来提升算法的路径探索能力,实现此组合优化理论在带时间窗的车辆路径问题中的应用.     

Research on a Calculation Method for the Damage Evaluation of the Existing Urban Tunnel Lining Structure北大核心CSCD

The operation safety of the public transport is seriously threaten by the occurrence of defects and damages in existing urban tunnels, which affects the quality of traffic, and will shorten the service life of urban tunnels. Therefore, it is of great significance to evaluate the damages of the tunnel lining structure quickly and accurately. The damage evaluation methods of the existing urban tunnel lining structure are investigated and analyzed in this paper, and a combination method of the macroscopic evaluation of the existing damaged urban tunnel and the damage mechanism of the lining structural material is proposed. Among them, the assessment method specified in the national criterion is selected to evaluate the damages of the lining structure for the macroscopic evaluation, and the classification of tunnel health levels is optimized. Meanwhile, the damage modulus based on the elastic modulus is selected, and the concept of elastic modulus reduction rate is introduced for the mechanism of damage. Furthermore, the assumed function relationship between the health level and the damage degree of existing urban tunnels is proposed and established, which provides a new idea for structural damage assessment of existing urban tunnels. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

Reverse time-restricted shortest paths: Application to air traffic management

In this paper, we consider a particular class of network flow problems that seeks a shortest path, if it exists, between a source node s and a destination node d in a connected digraph, such that we arrive at node d at a specified time τ while leaving node s no earlier than a lower-bounding time LB, and where the availability of each network link is time-dependent in the sense that it can be traversed only during specified intervals of time. We refer to this problem as the reverse time-restricted shortest path problem (RTSP), and it arises, for example, in the context of generating flight plans within air traffic management approaches under severe convective weather conditions. We show that this problem is NP-hard in general, but is polynomially solvable under a special regularity condition. A pseudo-polynomial time dynamic programming algorithm is developed to solve Problem RTSP, along with an effective heap implementation strategy. Computational results using real flight generation test cases as well as random simulated problems are presented.     

港口建设费征稽问题分析与对策的研究

港口建设费作为国务院批准征收的一项国家政府性基金,为对我国海上经济发展和港口基础建设提供了重要保障。文中通过实践调研与对比研究,对当前港口建设费征稽工作的现状和存在的问题进行多角度分析,提出港口建设费征稽工作的完善方向和解决对策,以期提高海事部门港口建设费征管能力,使我国港建费征收工作更加法制化、规范化、科学化。     

中小城市中心区停车问题研究

目前我国中小城市中心区的停车问题,已经成为制约城市可持续发展、影响城市交通顺畅、安全及人们生活质量的焦点问题.因此研究中小城市中心区的停车问题,提出近期建设管理策略和远期规划方案,对于缓解停车难问题具有必要性和紧迫性.