基于偏好函数与深度信念网络的自动化码头AGV实时调度算法

为提高自动化集装箱码头岸桥作业效率、降低自动导引车(Automated Guided Vehicle,AGV)空载行驶距离,以偏好函数和深度信念网络(Deep Belief Network,DBN)为核心设计AGV实时调度算法,完成AGV任务分配指派,优化AGV作业任务序列。利用偏好函数为处于待分配状态的AGV筛选最优集装箱,产生训练样本并更新训练集,通过DBN实时更新集装箱的偏好函数,重复该过程直至集装箱作业完毕。算例分析表明:同两种现行调度规则对比,AGV空载距离和岸桥作业时间显著下降;与人工神经网络(Artificial Neural Network,ANN)相比,DBN可有效提高算法精度与求解效率;算法针对环境动态变化实时分配集装箱,为自动化码头提高效率和降低能耗提供依据。     

江苏滨海LNG码头总平面布置设计要点

本文结合江苏滨海LNG码头工程,通过相关数模分析和操船模拟研究,归纳在侵蚀性粉沙海岸浪大、流急、泥沙淤积严重情况下建设大型LNG码头工程总平面布置设计要点;同时提出在水域受限情况下,布置大型LNG码头近、远期双侧靠船的研究思路,为类似工程设计提供借鉴。     

非恒定流对长江叙渝段航道整治建筑物坝面维修的影响

叙渝段航道整治建筑物坝面维修受上游金沙江、岷江枢纽电站的非恒定流影响明显。基于近年李庄、朱沱两站逐时水位资料,分析了两站水位变化特征。根据低水位集中、日变幅最小的原则提出了宜宾—合江、合江—重庆河段航道整治建筑物坝面维修的最佳施工时间,为保证坝面的质量,可适当减小坝面厚度或采取分段施工的方法。     

航电枢纽项目环境影响评价

针对航电枢纽项目环境影响评价中重点不突出、要点把握不够等问题,对赣江流域不同航电枢纽项目环境影响评价成果进行分析、研究,提出航电枢纽项目在政策、规划符合性分析、工程分析、生态影响评价、水环境和水文情势影响评价中的要点,对指导航电枢纽项目环境影响评价、减缓航电枢纽项目建设对环境的影响、优化航电枢纽环境保护设计和环境管理具有重要意义。     

BIM建模技术在海事码头结构设计中的应用

针对目前我国海事码头结构设计模块化程度较低的问题,基于两项在建海事码头工程,采用BIM建模技术进行结构设计,建立构件和设施模型,赋予设计参数,进行结构配筋,检验构造和功能,输出设计图纸和施工组织方案,获得模块化的设计成果,实现"实体工程"和"数字工程"的双移交。结果表明:BIM建模技术能以模块化的设计方法显著提高海事码头工程结构设计的质量和效率,实现成果共享,但建模标准尚未统一,行业内未能形成资源共享。     

Incorporating container location dispersion into evaluating GCR performance at a transhipment terminal

The degree of container dispersion at a transhipment terminal is measured by an index termed container location dispersion, which represents the range, both horizontal and vertical, of all containers for ship loading that are scattered in the yard. First, this paper identifies the impacts of container location dispersion on loading performance with insufficient or sufficient equipment deployment in real-life settings at a terminal. Then, we investigate those scenarios with different levels of interference. This research aims to explore the relationship between the container location dispersion and Gross Crane Rate (GCR) stability at a transhipment terminal and proposes a discrete-event driven simulation model for this purpose. All data in our experiments are extracted from the terminal operation system at a real-life container terminal. It is concluded from a series of experiments that the container location dispersion well captures the overall performance of container terminal handling and can be used for yard template optimization and management. Implications of this investigation are discussed in the context of the yard template design and improvement in the overall performance of a container transhipment terminal.     

Internalization of port congestion: strategic effect behind shipping line delays and implications for terminal charges and investment

This paper develops a theoretical model to analyze the congestion internalization of the shipping lines, taking into account the ‘knock on’ effect (i.e. the congestion delay passed on from one port-of-call to the next port-of-call). We find that with the presence of the knock-on effect, liners will operate less in terminals, and an increase of a liner’s operation in one terminal will decrease its operation in the other. If the liners are involved in a Stackelberg competition, whether they operate more or less in a terminal under the knock-on effect depends on the comparison between the marginal congestion costs of terminals. Furthermore, we find that the coordinated profit-maximizing terminal charges are higher than both the socially optimal terminal charges and the independent profit-maximizing terminal charges. When the knock-on effect is small, the independent profit-maximizing terminal charges are set at higher levels than the socially optimal terminal charges; but when the knock-on effect is sufficiently large, this relationship may reverse. Besides, the capacity investment rules are the same for welfare-maximizing terminal operator and coordinated profit-maximizing terminal operator, while independent profit-maximizing terminal operators invest less in capacity. The larger the knock-on effect, the larger this discrepancy.     

基于多智能体仿真的集装箱港口作业效率研究

集装箱港口生产作业系统是复杂的离散事件系统,数学建模方法难以构建针对整个系统的模型,而基于过程的仿真模型通常缺乏对设备调度的灵活性。为准确描述我国集装箱港口的作业流程,分析内卡配置数量对港口作业效率的影响,提出了基于事件驱动的集装箱港口多智能体(Multi-Agent)仿真模型。仿真结果表明:岸桥平均装卸效率(GCR)随着内卡数量的增加先急剧增加后缓慢增加,船舶平均等待时间(AWT)和平均在泊时间(AST)与岸桥平均装卸效率呈明显负相关关系。     

A literature review of flexible development of airport terminals

The Master Plan has long been the traditional go-to approach to airport development. It was originally conceived for a scenario of stable growth. In recent decades, however, the airport industry has undergone substantial structural changes, with the traditional Master Plan progressively revealing limitations with regard to airports coping with the market’s unpredictability. There have since been increased calls for flexibility in the approach as an alternative or as a complement to the traditional Master Plan. A flexible development plan helps to accommodate changes within terminals. This paper presents a review of the current literature on airport terminal flexibility, covering a total of 19 reference works. The works were analysed in terms of the concepts, definitions and deployment frameworks, or similar. The review reveals that research in airport terminal flexibility is still in its early stages. A consensual definition has yet to be defined and no robust framework for deploying flexibility has been defined. We propose a new definition of flexible development. Furthermore, flexibility has been studied essentially in the context of expansion. However, in certain regions where land availability is scarce, other forms of airport development may be more important. We conclude the paper with suggestions for future research areas.     

公路改扩建路基拓宽结合部处治方法

针对公路改扩建路基拓宽结合部的常见病害,深入分析其病害的成因———差异沉降。从填筑材料的固结本质、材料选取与施工工艺、拓宽结构设计方面探索了差异沉降机理,并提出了相应的处治方法,为公路改扩建工程提供重要参考。