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531.
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随着反舰导弹速度和机动性能的不断增大,现役舰载反导防御手段日显不足,迫切需要寻求新的防御手段。激光武器作为防御反舰导弹的一种有效手段,其跟瞄系统能否精确跟瞄反舰导弹是激光武器发挥效能的关键。文中从反舰导弹目标特性出发,采用数学建模和仿真分析方法,对舰载跟瞄系统的跟瞄精度要求作出了分析,建立了直线飞行和机动飞行2种反舰导弹运动模型,并推导了跟瞄系统相对角速度和角加速度控制量的计算模型。通过仿真计算,给出了不同条件下舰载跟瞄系统的动态能力要求。经分析明确了舰载跟瞄系统的能力需求,可为舰载跟瞄系统的论证与设计提供参考。 相似文献
533.
风能是一种优秀的绿色能源,随着风电开发延伸到海上,带有动力定位系统的风电安装船开始得到广泛应用。文章基于动力定位能力曲线对一艘风电安装船的动力定位系统进行失效分析,寻找出最危险的工况,为实际工程提供参考,以便在作业时尽量避开这些工况。 相似文献
534.
ABSTRACTThe pursuit of better performance by the local government can influence the investment decision-making related to port expansion. This paper compares the ceilings at which the port enterprise and the local government would stop making investments. To achieve this, the benefits to the port enterprise and the local government are measured over a given time period. An empirical study investigating how a port would respond if a rival port uses a type of capacity investment strategy is conducted for two major ports in Liaoning. The time at which the local government and the port enterprise would stop making investments and the final equilibrium are developed using the data from 2010. From the empirical results, it was found that investment in port capacity contributes greatly to the local government’s performance. Meanwhile, different investment ceilings are discovered for the port enterprise and the local government. This research is meaningful for discussing the institutional relationship between the local government and the port enterprise in China’s current decentralized port governance system.This paper is a revised and expanded version of a paper entitled ‘Port expansion mechanism in the context of political achievement of local government: a special phenomenon in China’ presented at International Association of Maritime Economists 2012 Taipei Conference during 5th September –8th September. 相似文献
535.
ABSTRACT With the increasing container cargo throughput and the arising of port congestion, container ports start to choose the investment expansion strategy to increase the port efficiency and then to figure out the problem of port congestion. To analyze this strategy, we formulate a non-cooperative game model for a two-terminals-one-port system, and derive the optimal equilibrium outcomes of the investment expansion strategy and investment constant strategy. In the game, we find that when the investment parameter of expansion strategy and impact of handling efficiency on demand changes, both pure-strategy Nash equilibrium and mixed-strategy Nash equilibrium exist, and two terminals are more likely to choose the investment expansion strategy in most cases. Numerical simulation is applied to explore the equilibrium strategy under different circumstance. 相似文献
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基于合作对策的江苏沿江港口合作竞争研究 总被引:1,自引:0,他引:1
江苏沿江港口群功能定位混乱、恶性竞争严重,不利于其整体竞争力的提高和"组合港"的发展,为此有必要形成良性竞争的合作模式。利用合作对策理论,建立了沿江港口在航线开辟上的合作模型。研究发现,沿江港口间的合作是有实质意义的,但各个港口在联盟中的地位是不同的,必须建立一定的利益分配原则来维持联盟的稳定性。研究结果表明:基于合作对策的沿江港口合作竞争模型有效地揭示各港的动态竞争行为,为研究港口合作竞争提供了一条新的途径。 相似文献
539.
This study investigates potential port users’ surplus and terminal operators’ profits due to transforming port governance from the ‘tool port’ model to the ‘landlord port’ model. Although the landlord port model is one of the most adopted and successful port governance models, many ports still operate under other models. Chittagong Port, the largest port in Bangladesh, currently operates under the tool port model, while the country’s second-largest port, Mongla Port, operates under the service port model. Chittagong Port is currently facing many challenges, including capacity expansion and renovation of port facilities. Therefore, we form four hypothetical situations for port governance model transformation, assuming that Chittagong Port will transform to the landlord port model but that Mongla Port will run under the existing governance model. Estimating a Bertrand game model, we present a cost-benefit analysis for port users and terminal operators (or port authorities) in hypothetical game situations. The results reveal that privatising one of the container terminals under a landlord setting is the most profitable scenario for Chittagong Port Authority, but privatising all terminals of Chittagong Port yields the highest users’ surplus. However, privatising two of the terminals while they cooperate yields the lowest users’ surplus. 相似文献