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931.
目前,SOA框架和相关技术已相当成熟。其提供一种复杂系统的集成框架,在计算机各个领域中发挥着重要作用。本文研究SOA框架的概念、特点和优势,以及在异构平台上实现不同功能集成与复用的方法,并提出一种利用SOA进行船舶电子信息系统仿真方案。对方案的流程和关键技术进行讨论和阐述,为复杂船舶电子信息系统的集成仿真打下基础。 相似文献
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Based on existing low-frequency water-filled impedance tube testing facilities, which is a part of the Low Frequency Facility of the Naval Undersea Warfare Center in Beijing, an improved water-filled pulse tube method is presented in this short paper. This proposed study is significantly different from the conventional pulse tube method because of the capability for a single plane damped sine pulse wave to generate in the water-filled pulse tube with a regular waveform and short duration time of about 1ms. During the generation process of the pulse, an inverse filter principle was adopted to compensate the transducer response. The effect of the characteristics of tube termination can be eliminated through the generation process of the pulse. Reflection coefficient from a water/air interface was measured to verify the proposed method. When compared with the expected theoretical values, a relatively good agreement can be obtained in the low frequency range of 500-2 000 Hz. 相似文献
935.
简要介绍了功率二极管在混合式断路器中的应用,在Matlab\Simulink中建立了二极管的反向恢复集总电荷模型,详细分析了串联二极管的反向恢复暂态过程,并进行了数学推导和仿真研究,计算和仿真结果表明了暂态分析方法的合理性和有效性. 相似文献
936.
Turbo码中交织器的设计直接影响着Turbo码的性能。在讨论Turbo码交织器的设计准则和类型的基础上,着重介绍了S随机交织器的原理,并给出了其一种基于冒泡排序算法的实现方法。仿真结果表明,中短长度的S随机交织器性能优良。 相似文献
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Verification of a simplified analytical method for predictions of ship groundings over large contact surfaces by numerical simulations 总被引:1,自引:0,他引:1
In this paper, a verification is presented of a simplified analytical method for the predictions from numerical simulations of structural performance during ship groundings over seabed obstacles with large contact surfaces and trapezoidal cross-section. This simplified analytical method was developed by Lin Hong and Jørgen Amdahl and calculates grounding characteristics, such as resistance and distortion energy, for double-bottomed ships in shoal grounding accidents. Two finite-element models are presented. One was built for a hold, and the other was built for a hold and a ship hull girder and also considers sectional properties, ship mass, added mass and the hydrodynamic restoring force. The verification was completed by comparing horizontal and vertical resistances and the distortion energy between seven numerical-simulation cases and a set of corresponding cases computed by a simplified analytical method. The results show that the resistances obtained by the simplified analytical method are close to the mean values of the resistance curves obtained by numerical simulations. The comparisons prove that the energy dissipation-prediction capability of the simplified analytical method is valuable. Thus, the simplified analytical method is feasible for assessing ship groundings over seabed obstacles with large contact surfaces and trapezoidal cross-section. Furthermore, studies of the influence of ship motion during groundings ascertained that ship motion affects structural performance characteristics. Resistances are lessened at the end of the grounding due to the reduction of indentations caused by heave and pitch motions of the ship hull girder. Finally, a new method for predicting the structural performance of the time-consuming complete-ship model by applying a combination of normal numerical simulations and ship-motion calculations is proposed and proven. 相似文献