对物流园区发展规划的几点认识

国内外实践证明,现代物流业发展已成为提升一个城市、一个地区乃至一个国家综合经济竞争能力的有效手段,在促进产业结构调整、转变经济发展方式和增强综合竞争力等方面发挥着重要作用.物流园区作为现代物流业主要空间载体,是为了实现物流设施集约化和物流运作共同化,集中建设的物流设施群与众多物流业者在地域上的物理集结地.文章对物流园区发展规划的一般思路和规划的重点环节进行探讨,并结合2个具体案列,对物流园区的发展规划提出一些建议,以期给物流园区规划相关人员提供参考.     

船舶维修作业速度控制策略研究

如何控制大型设备的维修进度，使其在规定的时间内保质保量地完成维修任务是维修企业一直要解决的问题之一，网络计划技术是解决该问题的有效途径．文中结合某船的整船修理介绍了网络计划技术在大型维修工程项目中的应用．     

浅谈公路工程造价控制与管理

详细论述了公路工程造价控制的重要性,从几个方面论述了工程造价控制的有效方法,并对工程造价控制和管理体制进行了认真探讨,对促进公路工程造价管理有一定借鉴意义。     

智能车避障路径规划方法研究

避障路径规划是智能车技术的关键部分,对智能车研究具有重大意义,正确的选择规划方法至关重要。本文首先初步选定人工势场法规划路径,仿真得知传统人工势场法规划出的路径存在局部最优、碰撞及达不到目标点的问题。因此提出改进人工势场法,通过改变势场函数和设定初始条件来解决此问题。最后,为了规划出能够同时避开静态和动态障碍物且能到达目标点的理想路径,在改进人工势场法中加入速度元素,经过仿真,证明了基于速度的改进人工势场法在智能车避障路径规划中的可行性和优越性。     

浅议沥青混凝土面层平整度

对面层平整度的重要性进行了说明,并详细介绍了不同的平整度指标和测定方法。同时对影响道路平整度的原因进行了分析,提出了相应的解决措施。     

Dual right-turn lanes in mitigating weaving conflicts at frontage road intersections in proximity to off-ramps

At frontage road intersections located downstream of freeway off-ramps, the use of dual right-turn lanes may provide improved weaving environments for right-turning vehicles from the off-ramp and reduce forced merges toward the desired right-turn bay. This paper investigates the safety impacts of the installation of dual right-turn lanes at frontage road intersections. A two-stage approach is used to estimate weaving conflicts as safety surrogates. In the first stage, micro-simulation models are calibrated based on field data to simulate vehicle trajectories. In the second stage, the trajectories are processed to estimate surrogate safety measures and frequency of weaving conflicts under different conditions. The two-stage approach is validated by correlation analysis between predicted weaving conflicts and actual crash rates. The results show that dual right-turn lanes can reduce weaving conflicts significantly compared to single exclusive right-turn lanes, and the safety benefits increase exponentially as weaving distance is reduced.     

上海轨道交通直流电力电缆的故障分析

直流1500V电缆是保障地铁正常运行的关键设施。介绍了上海地铁直流电缆的敷设方式和环境,在统计历史故障的基础上对直流电缆故障进行了分类,提出了在新线建设和改造项目中,尽可能采用带铠装的软电缆;通过在线检测手段,建立专家评估系统,评定绝缘的优劣并预警其劣化的趋势;改进直流电缆敷设质量,改善其运行环境等措施和建议。     

Logistics resources in seaport performance: multi-criteria analysis

Studying the logistics resource relationship within the framework of the overall performance of the main Iberian seaports performance, this article discusses how to apply the linear additive multi-criteria analysis (MCA) model and principal component analysis (PCA) to such an industry. The model incorporates the contribution of two different performance indicators—operational performance and physical capacity—measured by several indicators. First, we gather the 2009 annual data on the total cargo throughput of 16 seaport container terminals. The PCA method is then applied to attain the loading factor of each indicator and to normalize the redundancy in indicators and thereby generate meaningful results. We correspondingly find (a) operational performance contributed 48.77% while the physical capacity contributed 51.23% to overall performance; (b) the majority of seaports reveal a direct proportionality between their positioning in terms of physical capacity and their overall performance positioning; (c) this relationship changes whenever the difference in indicator value proves significant; and hence (d) this model demonstrates both its applicability and reliability in the case of the Iberian seaport industry and the relevance of encouraging multiple decision-makers to carefully consider identifying key criteria out of a given set of alternatives.     

冲击回波法主频在预制箱梁压浆密实度检测中的应用

采用冲击回波法对预制箱梁预应力管道压浆密实情况进行了无损检测。依据不同注浆密实度下冲击回波主频响应的不同,判断后张法预制箱梁孔道预应力金属波纹管中的压浆密实性状况。经凿开验证,冲击回波法能准确地对预应力管道的压浆密实程度进行判断,可有效地对预应力孔道进行压浆密实度检测。