分段计算方法在模拟爆炸应力波传播中的运用

针对爆炸加载下岩石响应的不同特点以及动力有限元和传统地震波模拟方法的局限性,提出了一种分段计算的数值模拟方法.该方法在空间上将所模拟的区域划分为非弹性段和弹性段,非弹性段内采用动力有限元计算方法,弹性段内采用传统的地震波方法,不同段之间以节点位移为边界条件.不同算法的数值模拟结果验证了分段计算方法用于模拟爆炸荷载产生地震波的有效性和正确性.     

舰炮一维修正弹校正诸元误差和预测误差试射

由于工作原理不同,舰炮使用传统无控弹试射方法不适用于一维弹道修正弹。分析了舰炮使用一维弹道修正弹射击误差构成和试射的必要性,提出了一维弹道修正弹校正射击诸元误差和预测误差试射新方法。首先通过分析对海射击以实际观测弹着水柱与提前点偏差作为发射诸元误差的精度,以及以预测弹着落点与实际观测弹着水柱偏差作为预测误差的精度,提出了求取诸元误差和预测误差的方法,论证了试射发数;然后从距离上和方向上校正诸元误差和预测误差。假设各误差值,通过仿真计算表明,按新方法试射能够显著提高射击精度。     

基于AIS的对海雷达多目标联合误差估计方法

提出了一种基于AIS的对海警戒雷达多目标联合误差估计方法,该方法以高精度AIS提供的目标信息为目标真值,对雷达进行误差估计。利用系统积累的多目标航迹信息,首先进行目标粗关联,将航迹信息进行时空对准后产生误差序列,通过单目标误差序列统计信息进行异常值的筛选,再通过多目标误差序列进行错误关联目标的检验,最终对剩余误差序列进行误差估计。通过实测数据和实际应用证明,该方法估计的雷达误差较准确,用估计结果对雷达误差进行校准后可有效减小对海雷达的系统误差。     

新型舵机结构运动分析与仿真

根据旋转弹弹道修正要求,提出一种基于4R空间机构的电动舵机结构,建立了理论分析模型,以空间机构学运动分析为基础,推导了机构输入、输出转角关系,绘制了理论分析转角曲线,建立机构三维模型,通过多刚体及刚柔耦合仿真验证分析了舵机转角关系和运动副受力情况,研究了该结构的可行性。计算分析结果表明,该舵机具有结构简单,动作可靠的优点,能满足舵机控制的转角精度和响应频率要求,适用于简易制导弹药。     

基于脉冲控制的末修弹飞行稳定性研究

脉冲力的瞬间作用会引起攻角和侧滑角的急剧变化,对末修弹飞行稳定性产生较大的影响.以线性化运动微分方程组为数学解析手段,对末修弹脉冲作用稳定性进行深入分析研究.数值仿真表明,采用小扰动法分析弹丸脉冲控制弹丸飞行稳定性是可行的.     

THE MORAL PERMISSIBILITY OF AUTOMATED RESPONSES DURING CYBERWARFARE

Automated responses are an inevitable aspect of cyberwarfare, but there has not been a systematic treatment of the conditions in which they are morally permissible. We argue that there are three substantial barriers to the moral permissibility of an automated response: the attribution, chain reaction, and projection bias problems. Moreover, these three challenges together provide a set of operational tests that can be used to assess the moral permissibility of a particular automated response in a specific situation. Defensive automated responses will almost always pass all three challenges, while offensive automated responses typically face a substantial positive burden in order to overcome the chain reaction and projection bias challenges. Perhaps the most interesting cases arise in the middle ground between cyber-offense and cyber-defense, such as automated cyber-exploitation responses. In those situations, much depends on the finer details of the response, the context, and the adversary. Importantly, however, the operationalizations of the three challenges provide a clear guide for decision-makers to assess the moral permissibility of automated responses that could potentially be implemented.     

考虑系统偏差的脉冲星守时算法研究

脉冲星拥有高度稳定的自转周期,可用对其的观测信息来校正星载原子钟钟差。针对脉冲星守时系统中脉冲到达时间的微小偏差会严重影响守时精度的问题,提出一种考虑系统偏差的脉冲星守时算法。基于脉冲星守时的基本原理,梳理了影响守时系统性能的系统偏差因素,并建立了模型。利用二步卡尔曼滤波算法,在估计原子钟钟差的同时,解耦估计系统偏差。研究结果表明,本算法可以有效地降低系统偏差对脉冲星守时系统的影响。该算法为脉冲星守时系统的工程实现提供了一条可行的思路。     

Multi-scale traffic vehicle detection based on faster R-CNN with NAS optimization and feature enrichment

It well known that vehicle detection is an important component of the field of object detection. However, the environment of vehicle detection is particularly sophisticated in practical processes. It is compara-tively difficult to detect vehicles of various scales in traffic scene images, because the vehicles partially obscured by green belts, roadblocks or other vehicles, as well as influence of some low illumination weather. In this paper, we present a model based on Faster R-CNN with NAS optimization and feature enrichment to realize the effective detection of multi-scale vehicle targets in traffic scenes. First, we proposed a Retinex-based image adaptive correction algorithm (RIAC) to enhance the traffic images in the dataset to reduce the influence of shadow and illumination, and improve the image quality. Second, in order to improve the feature expression of the backbone network, we conducted Neural Architecture Search (NAS) on the backbone network used for feature extraction of Faster R-CNN to generate the optimal cross-layer connection to extract multi-layer features more effectively. Third, we used the object Feature Enrichment that combines the multi-layer feature information and the context information of the last layer after cross-layer connection to enrich the information of vehicle targets, and improve the robustness of the model for challenging targets such as small scale and severe occlusion. In the imple-mentation of the model, K-means clustering algorithm was used to select the suitable anchor size for our dataset to improve the convergence speed of the model. Our model has been trained and tested on the UN-DETRAC dataset, and the obtained results indicate that our method has art-of-state detection performance.     

GPS弹道修正引信弹道环境信息的解算与数值仿真分析

根据质点弹道的特点, 描述了弹目间距、弹炮间距和相对弹道高 3个弹道环境信息的概念, 然后应用数学方法对弹目间距、弹炮间距和相对弹道高进行了理论计算推导, 建立了数学解算模型, 并用MATLAB程序进行了数值仿真计算, 通过分析其数值变化的规律和特点提出了其应用方向。     

速射转管炮射击校正方法

速射转管炮的使用成功地解决了射速高、寿命长、后坐力小三者之间的矛盾,但另一方面也给舰炮火控系统带来了新的问题。在分析转管炮对弹丸运动影响的基础上,重点描述了速射转管炮射击校正的方法。