Choice of loading clusters in container terminals

The storage allocation in the export yard of a container terminal determines the efficiency of container loading. Even if the yard manager has optimised the allocation of export containers to avoid rehandling, conflicts among loading quay cranes can still occur. Thus, all the possible handlings during loading must be considered when organising the yard space. In previous studies, the yard storage allocation has been assessed based on the subblock, which consists of several adjacent bays. However, to minimise all possible handlings in the loading process at the terminal, optimising more flexible storage clusters is also important. Thus, our aim in this research is to model the choice of loading clusters and derive a more flexible allocation strategy for organising the space in the export yard. A bi-objective model is built, which considers both the transportation distance and handling balance between blocks. A model aimed at minimising all possible handlings in the export yard for the loading process is also developed, and several of the insights derived can inform yard management in real-life operations. It is proven that the handling requirements have a significant effect on the choice of loading clusters, and yard managers should consider the various features of liner and loading processes when organising their storage space.     

Dynamic rolling strategy for multi-vessel quay crane scheduling

This paper focuses on the container loading and unloading problem with dynamic ship arrival times. Using a determined berth plan, in combination with the reality of a container terminal production scheduling environment, this paper proposes a scheduling method for quay cranes that can be used for multiple vessels in a container terminal, based on a dynamic rolling-horizon strategy. The goal of this method is to minimize the operation time of all ships at port and obtain operation equilibrium of quay cranes by establishing a mathematical model and using a genetic algorithm to solve the model. Numerical simulations are applied to calculate the optimal loading and unloading order and the completion time of container tasks on a ship. By comparing this result with the traditional method of quay crane loading and unloading, the paper verifies that the quay crane scheduling method for multiple vessels based on a dynamic rolling-horizon strategy can provide a positive contribution to improve the efficiency of container terminal quay crane loading and unloading and reduce resource wastage.     

集装箱底板钻孔小车左右轮实时修正的实现方法

介绍集装箱底板钻孔小车左右轮实时修正的实现方法,通过在左右从动轮安装的旋转编码器进行位置检测,PLC实时修正左右主动轮伺服电机的运行速度,小车基本实现直线运行。     

企业“门户”系统建设探究

本文应用技术手段整合企业现有应用系统,构建企业门户平台,可以为使用者提供统一使用平台。提高企业的工作效率。     

Hybrid Estimation of Distribution Algorithm for the Quay Crane Scheduling Problem

The competitiveness of a container terminal is highly conditioned by the time that container vessels spend on it. The proper scheduling of the quay cranes can reduce this time and allows a container terminal to be more attractive to shipping companies. The goal of the Quay Crane Scheduling Problem (QCSP) is to minimize the handling time of the available quay cranes when performing the tasks of loading and unloading containers onto/from a container vessel. This paper proposes a hybrid Estimation of Distribution Algorithm with local search to solve the QCSP. This approach includes a priori knowledge about the problem in the initialization step to reach promising regions of the search space as well as a novel restarting strategy with the aim of avoiding the premature convergence of the search. Furthermore, an approximate evaluation scheme is applied in order to reduce the computational burden. Moreover, its performance is statistically compared with the best optimization method from the literature. Numerical testing results demonstrate the high robustness and efficiency of the developed technique. Additionally, some relevant components of the scheme are individually analyzed to check their effectiveness.     

An ALE finite element method for baffled fuel container in Yawing motion

A computational analysis of engineering problems with moving domain or/and boundary according to either Lagrangian or Eulerian approach may encounter inherent numerical difficulties, the extreme mesh distortion in the former and the material boundary indistinctness in the latter. In order to overcome such defects in classical numerical approaches, the ALE (arbitrary Lagrangian Eulerian) method is widely being adopted in which the finite element mesh moves with arbitrary velocity. This paper is concerned with the ALE finite element formulation, aiming at the dynamic response analysis of baffled fuel-storage container in yawing motion, for which the coupled time integration scheme, the remeshing and smoothing algorithm and the mesh velocity determination are addressed. Numerical simulation illustrating theoretical works is also presented.     

Coupled flexural and torsional vibrations of ship-like girders

The paper is related to investigation of coupled horizontal flexural and torsional vibrations of container vessels. Differential equations of coupled vibrations of a prismatic beam with open cross-section are derived. The equations are solved analytically by direct integration and by variational method. In the former case, the frequency equation is reduced to a polynomial of the fourth order. In the latter case, beam deflection and twist angle are assumed in the form of series of natural modes of uncoupled vibrations of free beam with suspended warping. The variational method manifests very fast convergence and high accuracy. Application of the developed methods is illustrated in the case of a prismatic pontoon with cross-section of a container vessel. The same numerical example is used for checking 1D FEM mathematical model and code developed for analyses of real structures of container vessels with variable cross-sections. In addition, correlation analysis of 1D and 3D FEM results is done to validate the accuracy of the former.     

1.6MW集装箱电站通风系统设计

集装箱电站是一个将发电机组和各个外围辅助系统集成的一个设备，可以在户外直接使用的电力装置。而通风系统设计的好坏将直接影响到集装箱电站的发电能力。在此，主要介绍了某型集装箱电站通风系统设计的思路和方法。     

横平竖“直” 20世纪70年代中前期和80年代初期建筑关系中的历史连续性

文章试图改变以政治影响下的社会历史分期作为中国建筑现代史分期依据的现状,一方面寻找中国现代主义建筑的内在线索：另一方面,通过重新引入几个相对被忽视的建筑作品,联系所谓的“政治建筑”和改革开放30年初期发生的“突变”,来强调中国现代建筑史的内部连续性。     

A beam search approach to the container loading problem

The single container loading problem is a three-dimensional packing problem in which a container has to be filled with a set of boxes. The objective is to maximize the space utilization of the container. This problem has wide applications in the logistics industry. In this work, a new constructive approach to this problem is introduced. The approach uses a beam search strategy. This strategy can be viewed as a variant of the branch-and-bound search that only expands the most promising nodes at each level of the search tree. The approach is compared with state-of-the-art algorithms using 16 well-known sets of benchmark instances. Results show that the new approach outperforms all the others for each set of instances.