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891.
从码头型式和码头前沿装卸工艺两方面提出了提高长江中上游斜坡码头装卸效率的措施,并对文中所提出的各种装卸工艺系统进行了码头通过能力计算,以供长江中上游集装箱码头改建和新建时参考。 相似文献
892.
2004年初,上海港开始使用双40′桥吊。介绍了双40′桥吊的应用情况,将双40′和单40′桥吊的使用数据作了比较,随后进行了综合分析。最后,对双40′桥吊的发展趋势和努力方向作了阐述。 相似文献
893.
介绍了宁波北仑国际集装箱码头有限公司为配合集装箱生产管理系统(NBCT MS)配备的无线集群通讯系统。介绍了无线集群通信系统的基本组成及功能,适用于码头的无线集群通信系统的实施与开发,并提出了无线集群系统实施后的问题,提出了扩容方案。 相似文献
894.
895.
An iterative transmit power allocation (PA) algorithm was proposed for group-wise space-time block coding (G-STBC) systems with group-wise successive interference cancellation (GSIC) receivers. Group-wise interference suppression (GIS) filters are employed to separate each group's transmit signals from other interferences and noise. While the total power on all transmit symbols is constrained, all transmit PA coefficients are updated jointly according to the channel information at each iteration. Through PA, each detection symbol has the same post-detection signal to interference-and-noise ratio (SINR). The simulation results verify that the proposed PA algorithm converges at the equilibrium quickly after few iterations, and it achieves much lower bit error rates than the previous single symbol SIC PA and the fixed ratio PA algorithms for G-STBC systems with GSIC receivers . 相似文献
896.
A New Traffic Model for Mobile Wireless Networks 总被引:1,自引:1,他引:0
A new traffic model for mobile wireless networks was given and analysed. In the model, it is considered of traffic characteristic for two special periods of time. A pre-emptive priority scheme combined with channel borrowing strategy according to the speciality was proposed. All the channels can be used by non-real-time services, and real-time services are given higher priority for they are allowed to pre-empt channels used by non-real-time services. Either real-time handoff requests or non-real-time handoff requests can be queued in queues when there is no channel can be used. Some channels are reserved for real-time handoff requests, which can also be used by non-real-time service when they are idle. Simulation results are also given. It is seen that our scheme performs better than other schemes when the arrival rate of real-time services is much higher than non-real-time services. 相似文献
897.
898.
本文总结了青岛港集装箱自动化码头的建设实例,结合场区堆场结构的优化设计,运用海绵城市的设计理念,对堆场排水系统进行了优化设计;比较了连锁块铺面堆场和箱角梁堆场的排水沟结构,给出箱角梁基础集装箱堆场排水沟的优化设计结论. 相似文献
899.
Containership stowage plans are a pivotal teaches in the system of container transportation. With the increasing containers shipping, planning containership stowage has become more and more complicated. So intelligent stowage planning for containerships is of great significance. An effective stowage plan may improve efficiency of transportation system. First, the progress of containership stowage plan at home and abroad is reviewed, including the latest developments, such as the application of various optimization methods and computer techniques to the problem. Then, the complexities of the problem are discussed and areas where investigations are still needed are pointed out. This will provide a reference for further research on the subject. 相似文献
900.