共查询到17条相似文献,搜索用时 734 毫秒
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针对低频主动拖线阵声纳通过发射低频声信号对水下目标进行探测这一特性,提出了使用强声源对低频主动拖线阵声纳实施压制性干扰的方法,并对影响强声源干扰效果的因素进行了仿真分析。结果表明,在综合考虑这些影响因素的前提下,使用该方法能够达到较好的干扰效果。 相似文献
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着眼于低截获雷达系统的工程实现,提出了一种实现简单,性能优越的基于TENT映射的新型低截获脉压雷达信号波形,该波形采用了脉间由混沌信号控制码型跳变,脉内由m序列调相,相邻脉冲采用m序列优选对的低截获波形设计技术。分析了这种雷达信号波形的数学模型和统计特性,从平均模糊函数的角度讨论了该雷达信号与真随机二相码调相之间的关系并给出了其对应的波形产生与信号处理模块系统框图。理论分析和仿真结果均表明,这种雷达信号波形具有良好的距离速度分辨力、很低的截获概率和优异的ECCM性能,工程上也易于产生和处理。 相似文献
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航渡中反潜直升机的配置 总被引:2,自引:0,他引:2
水面舰艇编队航渡时,针对潜艇威胁,通常利用反潜直升机隐蔽、迅速的优势,将其配置在某一区域实施警戒,以达到对潜防御的目的。本文基于潜艇的威胁方向,分别对编队前方、侧翼以及综合前方和侧翼,探讨了反潜直升机警戒线的配置方法。在确定反潜直升机使用吊放声呐搜索方法的基础上,采用自同步思想,对反潜直升机警戒线的配置参数给出了定量描述。得出的结论实用、可行,为制定对潜防御方案提供了参考依据。 相似文献
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Ming-Miin Yu 《Maritime Policy and Management》2013,40(1):98-120
This study presents an alternative approach to evaluate the efficiency of the logistics performance index (LPI) of individual countries. This study considers the differences among technology groups by classifying and comparing the countries as high-income Organization for Economic Co-operation and Development (OECD), high-income non-OECD, upper-middle-income, lower-middle-income, and low-income countries. The meta-frontier data envelopment analysis with assurance regions (Meta-DEA–AR) model is proposed to evaluate LPI scores and differences accurately among groups. For conformity with the ranking of original World Bank LPI, the assurance region of each logistics indicator is obtained by a regression model. The results show that the LPI rankings obtained by the proposed model are very comparable to those of World Bank LPI. Without distorting the rankings, the results offer several managerial suggestions for those countries with inefficiency in their LPIs. 相似文献