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901.
舰船抗爆和抗冲击技术概念宏观,内涵广泛,对其认识理解、设计研究都需要技术体系的顶层划分和牵引。首先,基于武器攻击对舰船的爆炸毁伤类型,对舰船抗爆与抗冲击这两个概念进行划分;然后,基于舰船总体抗爆抗冲击设计技术需求,区分不同的研究对象及技术的基础理论,提出包含6大类型的舰船抗爆抗冲击技术体系的划分方案,即水上/水下防护结构设计、新型抗爆结构与毁伤分析、设备系统及人员抗冲击、舰船抗爆抗冲击试验验证及技术标准规范;最后,分别对舰船抗爆和抗冲击技术内涵进行详细阐述。所做研究可为我国舰船抗爆抗冲击技术体系的形成提供一个初步构想,供从事舰船抗爆抗冲击设计、研究及管理人员参考。 相似文献
902.
[Objective]This study aims to explore the law of the critical compression stress of stiffened panels under the influence of in-plane shear load, and whether in-plane shear load combined with lateral pressure will introduce a strong coupling effect. [Method ] To this end, nonlinear finite element (FE) software ABAQUS is used to perform numerical simulation analysis under combined loads on a group of FE models. A limit state equation/curve is then derived from the dimensionless calculation results based on the minimum square error method. [Results]The results show that the influence law of in-plane shear load on the critical compression stress of stiffened panels is clarified, and a limit state equation of stiffened panels that considers the effect of shear load is obtained. [Conclusion]The limit state equation in this paper can provide references for modifying the ultimate strength of stiffened panels under the influence of in-plane shear load. © 2023 Chinese Journal of Ship Research. All rights reserved. 相似文献
903.
[Objectives]Aiming at the current situation in which it is difficult to efficiently evaluate protection probability through traditional lightning rod evaluation methods, an efficient numerical evaluation algorithm is developed on the basis of an electrogeometric model (EGM) and attractive volume to realize the efficient calculation of lightning protection probability at any point in space.[Methods]This method first determines the attractive volume boundary of the lightning rod and protection object according to the interception process of the upward and downward leaders. The collection surface and exposure arc of the lightning stroke distance are then calculated, enabling the attractive risk and interception effect of the lightning rod to be quantified. Finally, the attraction and interception characteristics of the lightning rod are integrated to establish a numerical evaluation model of protection probability. To verify the accuracy of this method, the general rule of lightning rod protection probability is analyzed and the results compared with the existing analysis method.[Result]The evaluation results of this method show good agreement with those of classical leader progression model (LPM) theory.[Conclusions] The method proposed herein has a high degree of quantification and can realize the efficient calculation of lightning protection probability at any point in space, which can provide useful references for lightning protection design work. © 2023 Authors. All rights reserved. 相似文献
904.
[目的]针对固定的海洋区域,研究欠驱动水面无人船(ASV)集群的抗干扰最优覆盖控制问题。[方法]首先,在运动学层级,基于邻居ASV位置和环境密度信息进行Voronoi分配,设计欠驱动ASV运动学制导律,引导ASV运动到最优目标点;然后,考虑复杂海洋环境下ASV模型的不确定性以及风浪流引起的外部扰动,在动力学层级设计一种固定时间扩张状态观测器(FTESO),并基于FTESO设计固定时间的动力学控制律。[结果]稳定性分析结果表明了ASV集群的抗干扰最优覆盖控制闭环系统的误差是有界的,仿真结果验证了该方法的有效性。[结论]通过采用该抗干扰最优覆盖控制器,ASV集群可以在任意的初始位置实现对目标区域的最优覆盖。 相似文献
905.
An J.Yang S.Xiang X.Dong D. 《中国舰船研究》2023,(2):184-193
[Objectives]To ensure safety and prevent seabed collisions in complex unknown underwater environments, this study proposes a seabed safety domain model and tiered emergency response strategies. [Methods]A vertical motion simulation model is established and verified by surpassing the test results, then used to calculate the active and passive safety domain distance of an autonomous underwater vehicle (AUV), thereby establishing a seabed safety domain model. An AUV emergency control system and emergency strategies are then built on the basis of the dynamic safety domain model. The trim and distance from the seabed of the AUV are used to calculate the current and future risk factors. Based on the weighted sum, the comprehensive risk factor is employed to provide the AUV with emergency response strategies.[Results]Lake tests with the AUV sailing at a fixed depth and height show a strong dependency of the comprehensive risk coefficient on seabed height when it is close to the boundary of the AUV's active safety domain. In the opposite case, there is a weak dependency of the comprehensive risk coefficient on seabed height. The results show that the proposed AUV emergency control system can reduce emergency false alarms caused by frequently changing riverbed heights and sailing altitudes close to the seabed. In such cases, reasonable emergency strategies can be realized under complex rough terrain.[Conclusions]The AUV seabed safety domain model and tiered emergency response strategies based on vertical motion equations proposed herein can be applied to evaluate seabed collision risk in various cases. Finally, this paper provides emergency response strategies to avoid seabed collision accidents, which can enhance the safety of AUV navigation. © 2023 Chinese Journal of Ship Research. All rights reserved. 相似文献
906.
无人船(USV)集群作为未来海上军事运用的重要组成力量,是各国海上无人装备的重要发展方向。首先,通过梳理总结当前国外无人船集群发展战略规划与运用现状,对无人船集群作战关键技术进行归纳分析,从集群自组网通信、战场态势感知、集群协同任务分配等3个方面剖析无人船集群相关技术的研究进展;然后,对无人船集群在军事上运用的典型样式和主要效益进行分析及研判;最后,总结分析当前应对无人船集群的难点,并对无人船集群应对的技术发展予以展望。 相似文献
907.