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991.
1问题的提出啃轨是门吊使用中常见故障,主要由于门吊在运行中车轮偏斜运行,车轮边缘与走行钢轨之间产生严重摩擦。我公司大部分货场都使用20T门吊,由于架设比较早,使用时间较长,在运行过程中多台门吊出现大小车不同程度的啃轨现象,车轮边缘和钢轨间严重磨损,这些导致小车运行机构的运行阻力增大、电动机功率额外损耗、传动部件受力增加,时间长将导致车轮磨损超限报废,如果不及时进行更换,严重的将危及安全,影 相似文献
992.
Validation of a schedule‐based capacity restraint transit assignment model for a large‐scale network
This paper describes the application of a capacity restraint trip assignment algorithm to a real, large‐scale transit network and the validation of the results. Unlike the conventional frequency‐based approach, the network formulation of the proposed model is dynamic and schedule‐based. Transit vehicles are assumed to operate to a set of pre‐determined schedules. Passengers are assumed to select paths based on a generalized cost function including in‐vehicle and out‐of‐vehicle time and line change penalty. The time‐varying passenger demand is loaded onto the network by a time increment simulation method, which ensures that the capacity restraint of each vehicle during passenger boarding is strictly observed. The optimal‐path and path‐loading algorithms are applied iteratively by the method of successive averages until the network converges to the predictive dynamic user equilibrium. The Hong Kong Mass Transit Railway network is used to validate the model results. The potential applications of the model are also discussed. 相似文献
993.
随着珠江三角洲经济的蓬勃发展,通过大鹏湾盐田港进出口的货物越来越多,对航行珠江经东博寮至盐田港航线的集装箱船的需求也在不断增加。由于盐田港属于海区,因此航行该航线的集装箱船要么设置货舱口盖,要么满足敞口集装箱的要求而不设置货舱口盖。目前航行珠江三角洲的集装箱船由于船型小和成本关系,设置可在其上装载集装箱的钢质 相似文献
994.
995.
996.
日前,GPS全球定位系统在全世界得到了广泛的应用,其用户端设备-GPS接收机的技术水平随之迅猛发展。软件无线电技术使GPS接收机更加灵活:通过Matlab平台,仿真GPS软件接收机前端下变频,滤波与抽样;产生数字中频信号,实现捕获跟踪算法;并与Galileo信号进行了对比分析。验证了算法的可行性。 相似文献
997.
本文从国际航行船舶有效申报的重要性和电子申报的必然性,阐述了推行诚信申报机制必将成为具有明显优势的管理模式。 相似文献
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999.
Thomas A. Mensah 《WMU Journal of Maritime Affairs》2004,3(1):17-30
The adoption of the International Ship and Port Facility Security Code (ISPS Code) is the latest response of the international
shipping community to the increasing threat posed by acts of terrorism at sea. The ACHILLE LAURO incident of 1985 showed that
the traditional law against piracy was not adequate to deal with new types of unlawful acts against international shipping,
especially those involving acts of terrorism. The 1988 Convention for the Suppression of Unlawful Acts against the Safety
of Maritime Navigation (SUA Convention) and the technical and administrative measures adopted by the Maritime Safety Committee
of IMO in 1986 and 1996 attempted to develop a broader regime to deal with unlawful acts against international shipping.However,
the events of September 11, 2001 showed that additional measures were still needed to prevent terrorist attacks against ships. 相似文献
1000.
The establishment and implementation of a training programme requires a training needs assessment (TNA). Without this approach, more often than not, training programmes have failed to succeed and to make such an assessment the instructional designer, i.e. the person in charge for this work, needs to follow a methodology. Unlike the other industries, the port industry has neglected the use of these methodologies, which is shown by the lack of research work published in academic journals. With a view to fill the existing gap, the paper proposes a five-step TNA methodology to be used in the port industry and applies its first three steps to investigate the port training situation in the new European Union member states. To achieve this objective, the paper is structured in the following way: puts the research work into context; addresses the role of ports; presents a port TNA methodology; explains research methodology; addresses port training issues in the new European-member states; and presents conclusions and further comments. 相似文献