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Hyung Rim Choi Hyun Soo Kim Byung Joo Park Nam-Kyu Park Sang Wan Lee 《Maritime Policy and Management》2013,40(3):197-210
The major characteristics of ERP (Enterprise Resource Planning) are an enterprise-wide system that covers all the business functions and information resources, integrated database, built-in best industry practice, packaged software and open architecture. ERP enables reduction of system development time, flexibility, standardization of workflow and effective business planning capability. ERP is mainly for the manufacturing industry. However, the principles of ERP can also be applied to container terminal operating systems. This paper presents an ERP system approach for a container terminal. It has clustered the workflow of a container terminal and analysed the business process to generate the best workflows. The integrated database is designed to eliminate redundancy and keep integration. The core of ERP for container terminal is the planning facility such as berth planning and yard planning. The planning capability is very tightly coupled with data flow from client entities such as shipping companies. The ERP can handle the existing problems of container terminal operation that are mainly caused by lack of integration of a whole information resource in a container terminal, ad-hoc and poor planning capability, disconnected and incorrect data from client companies. The ERP approach can not only resolve the problems of container terminals but also promote adoption of information systems for container terminals in the world that have not yet implemented terminal operating systems. 相似文献
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基站覆盖优化问题是移动通信网络优化的核心问题.针对网络节点严重冗余,基站之间相互干扰的情况,提出了一个移动通信网络基站最优覆盖模型,并利用人工鱼群算法对移动通信网络基站覆盖优化问题进行求解,得到了最优设计方案.最后选取某城市核心区域对模型与算法进行了验证,仿真结果表明:本文提出的方法提高了移动通信网络基站的覆盖率,减少了节点冗余,从而达到减少网络建设成本,提高网络规划效率和准确度的网络优化目的. 相似文献
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双块式无碴轨道轨枕具有良好的平顺性和持久可靠的稳定性,极少的线路维修量.双块式轨枕预制工艺可分为钢筋骨架加工和混凝土预制两大部分.结合武广客运专线某轨枕场的生产实践,介绍了双块式轨枕的制造工艺和技术特点,提出了改进工艺和提高质量的具体措施. 相似文献
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通过模型试验对高速铁路列车通过带有辅助坑道的隧道时形成的气压波动进行模拟,并对试验结果进行分析,研究高速铁路隧道辅助坑道的位置、长度及断面面积对瞬变压力的影响.试验结果表明,辅助坑道的位置不同,即反射界面的位置不同,会导致产生膨胀波的叠加位置发生变化,从而对列车上空气压力波动会产生有利或不利影响;根据叠加原理,可以得出影响隧道瞬变压力的长隧道中辅助坑道最有利和不利位置.通过压力波动曲线比较可知,辅助坑道的长度对隧道内瞬变压力的影响不大;但辅助坑道的断面积不宜过大,否则会产生不利影响. 相似文献
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In this paper, numerical simulations of vortex-induced vibrations in a vertical top-tension riser with a length-to-diameter ratio of 500 using our in-house code viv-FOAM-SJTU are presented. The time-dependent hydrodynamic forces on two-dimensional strips are obtained by solving the Navier-Stokes equations, which are, in turn, integrated into a finite-element structural model to obtain the riser deflections. The riser is discretized into 80 elements with its two ends set as pinned and 20 strips are located equidistant along the risers. Flow and structure are coupled by hydrodynamic forces and structural displacements. In order to study the effects of the shear rate, of the current profiles on the vortex-induced vibrations in the riser, vibrations, with varying shear rates, in both the in-line and cross-flow directions, are simulated. In addition to the time domain analysis, spectral analysis was conducted in both the temporal and spatial domains. Multi-mode vibration characteristics were observed in the riser. The relationship between dominant vibration mode number and the shear rate of current profiles is discussed. In general, the overall vibrations in the riser pipe include contributions from several modes and each mode persists over a range of shear rates. Moreover, the results suggest that with a larger shear rate the position of the maximum in-line time-averaged displacement will move closer to the end where the largest velocity is located. 相似文献