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典型体制雷达引信信号的调制制式识别

探测与控制学报 2016年第5期38卷 6-9页

作者：朱航张淑宁赵惠昌南京理工大学电子工程与光电技术学院解放军73015部队

针对现有方法只能识别某一类特定信号的不足,为了有效识别出几类典型体制雷达引信信号,提出了基于调制周期估计及时频脊线提取的信号调制制式识别方法。该方法对信号自相关函数进行分析以估计调制周期,而后估计包络波形以完成对占空比... 详细信息

针对现有方法只能识别某一类特定信号的不足,为了有效识别出几类典型体制雷达引信信号,提出了基于调制周期估计及时频脊线提取的信号调制制式识别方法。该方法对信号自相关函数进行分析以估计调制周期,而后估计包络波形以完成对占空比的估计来区分脉冲串信号类型;对于连续波信号通过周期积累和时频脊线提取,利用几项特征参数识别调制制式。仿真分析表明,该方法具有较高的识别准确率。

关键词：雷达引信信号调制周期包络波形时频脊线周期积累

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弹载合成孔径雷达成像处理算法综述

探测与控制学报 2015年第6期37卷 1-6,11页

作者：陈勇赵惠昌陈思张淑宁南京理工大学电子工程与光电技术学院江苏南京210094

弹载合成孔径雷达(SAR)成像是近年来雷达成像领域的研究热点之一。在介绍弹载SAR成像特点和传统SAR成像算法理论基础上,根据弹载SAR运动特点,对弹载SAR成像算法进行了总结和分析。通过分析各种弹载SAR成像算法的优缺点,讨论了弹载SAR技... 详细信息

弹载合成孔径雷达(SAR)成像是近年来雷达成像领域的研究热点之一。在介绍弹载SAR成像特点和传统SAR成像算法理论基础上,根据弹载SAR运动特点,对弹载SAR成像算法进行了总结和分析。通过分析各种弹载SAR成像算法的优缺点,讨论了弹载SAR技术应用中有待解决的问题,对弹载SAR成像算法的研究现状和发展趋势进行了较为全面的综述。

关键词：弹载合成孔径雷达成像算法非匀直弹道

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基于引信信号周期性的分形噪声去噪方法

探测与控制学报 2014年第3期36卷 1-5,15页

作者：朱航张淑宁赵惠昌南京理工大学电子工程与光电技术学院解放军73015部队

针对海杂波背景下的引信信号去噪问题,提出一种基于引信信号周期性的分形噪声去噪方法。该方法首先利用小波分析对分形噪声进行白化,而后充分利用引信信号的周期性,去除白化后的噪声,最后对于去噪后的信号,按照白化的逆过程进行小波分... 详细信息

针对海杂波背景下的引信信号去噪问题,提出一种基于引信信号周期性的分形噪声去噪方法。该方法首先利用小波分析对分形噪声进行白化,而后充分利用引信信号的周期性,去除白化后的噪声,最后对于去噪后的信号,按照白化的逆过程进行小波分解和重构,得到较为理想的引信信号。实践证明,此方法能够较好地去除分形噪声,得到与原始波形相似度极高的去噪后信号,并且对于同时含有白噪声和分形噪声的情况也同样适用,即使是在信噪比较低的情况下,该方法也能有较好的信噪比改善能力。

关键词：分形噪声小波分解重构噪声白化滤波周期性

Recycling arsenic-containing bio-leaching residue after thermal treatment in cemented paste backfill:Structure modification,binder properties and environmental assessment

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2136-2147页

作者： Dengfeng zhao Shiyu Zhang Yingliang zhao Department of Mining Engineering Lyuliang UniversityLvliang 033000China School of Civil and Environmental Engineering University of Science and Technology BeijingBeijing 100083China School of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 00852China

The substantial arsenic(As)content present in arsenic-containing bio-leaching residue(ABR)presents noteworthy environ-mental challenges attributable to its inherent instability and susceptibility to *** its elevated calcium sulfate content,ABR exhibits considerable promise for industrial *** study delved into the feasibility of utilizing ABR as a source of sulfates for producing super sulfated cement(SSC),offering an innovative binder for cemented paste backfill(CPB).Thermal treatment at varying temperatures of 150,350,600,and 800℃ was employed to modify ABR’s *** investigation encompassed the examination of phase transformations and alterations in the chemical composition of As within ***,the hydration characteristics of SSC utilizing ABR,with or without thermal treatment,were studied,encompassing reaction kinetics,setting time,strength development,and *** findings revealed that thermal treatment changed the calcium sulfate structure in ABR,consequently impacting the resultant sample ***,calcination at 600℃ demonstrated optimal modification effects on both early and long-term strength *** enhanced performance can be attributed to the augmented formation of reaction products and a densified ***,the thermal treatment elicited modifications in the chemical As fractions within ABR,with limited impact on the As immobilization capacity of the prepared binders.

关键词： cemented paste backfill bio-leaching residue arsenic immobilization binder hydration calcination

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近炸引信中的开槽共形定向微带天线

探测与控制学报 2014年第5期36卷 26-28,33页

作者：狄萃赵惠昌杨云星南京理工大学电子工程与光电技术学院江苏南京210094

针对近炸引信中贴片微带天线带宽窄及定向辐射性能差等问题,提出了与弹体共形的具有侧向辐射、宽频带的微带天线。该微带天线采用倒方形贴片,在贴片上进行开方形槽,并在槽中加入圆形寄生贴片对天线性能进行优化。仿真与实物测试的结果表... 详细信息

针对近炸引信中贴片微带天线带宽窄及定向辐射性能差等问题,提出了与弹体共形的具有侧向辐射、宽频带的微带天线。该微带天线采用倒方形贴片,在贴片上进行开方形槽,并在槽中加入圆形寄生贴片对天线性能进行优化。仿真与实物测试的结果表明:开槽的共形定向微带天线具有良好的宽带特性,在中心频率7.7GHz附近方向图具有良好的侧向辐射性能,指标优良且尺寸小,满足近炸引信所需。

关键词：侧向辐射弹体共形微带天线寄生贴片近炸引信

Automatic modeling algorithm of stochastic error for inertial sensors

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Control Theory and Technology 2024年第1期22卷 81-91页

作者： Luodi zhao Long zhao School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China Digital Navigation Center Beihang UniversityBeijing100191China Science and Technology on Aircraft Control Laboratory Beihang UniversityBeijing100191China

This paper proposes an automatic algorithm to determine the properties of stochastic processes and their parameters for inertial error. The proposed approach is based on a recently developed method called the generalized method of wavelet moments (GMWM), whose estimator was proven to be consistent and asymptotically normally distributed. This algorithm is suitable mainly (but not only) for the combination of several stochastic processes, where the model identification and parameter estimation are quite difficult for the traditional methods, such as the Allan variance and the power spectral density analysis. This algorithm further explores the complete stochastic error models and the candidate model ranking criterion to realize automatic model identification and determination. The best model is selected by making the trade-off between the model accuracy and the model complexity. The validation of this approach is verified by practical examples of model selection for MEMS-IMUs (micro-electro-mechanical system inertial measurement units) in varying dynamic conditions.

关键词： GMWM Stochastic process Inertial sensor Sensor calibration Error model Allan variance

Meeting the challenges of invasive alien species

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National Science Review 2024年第3期11卷 296-298页

作者： Weijie zhao NSR news

The Xinjiang Uygur Autonomous Region of China is famous for its tomato production. Abundant sunshine, large day–night temperature difference and the abundant irrigation by snowmelt from the Tianshan Mountains produce...

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Ling-Ling Chen: RNA has its own features;don't study it as a protein

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National Science Review 2024年第2期11卷 301-305页

作者： Weijie zhao NSR

Non-coding RNA(ncRNA) has been a very active research area over the past 30 years. From small nc RNA – the discovery of RNA interference won the lead researchers the Nobel Prize, to long ncRNA(lncRNA), which has attracted much attention in recent years, various nc RNAs participate in all kinds of biological processes and show a variety of biomedical application prospects.

关键词： RNA

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伪随机码调制脉冲串引信及其抗噪性能分析

弹箭与制导学报 2006年第S2期26卷 469-472页

作者：熊刚杨小牛赵惠昌张淑宁中国电子科技集团第36所通信对抗技术国家重点实验室浙江嘉兴314001 南京理工大学引信抗干扰实验站江苏南京210094

给出了几种常见伪随机码调制脉冲串信号的统一数学表达式,包括脉间伪随机二相编码脉冲串信号、伪随机脉位调制脉冲串信号、伪随机脉位调制与二相编码复合脉冲串信号,以此为基础,简要推导了统一的幅谱函数和相关函数表达式,具体分析了各... 详细信息

给出了几种常见伪随机码调制脉冲串信号的统一数学表达式,包括脉间伪随机二相编码脉冲串信号、伪随机脉位调制脉冲串信号、伪随机脉位调制与二相编码复合脉冲串信号,以此为基础,简要推导了统一的幅谱函数和相关函数表达式,具体分析了各自的特性并对其进行了仿真。接着,从引信接收机信号处理的角度,推导了从相干解调和相关检测过程的信噪比增益公式,详细分析了伪码脉冲体制引信的抗噪声性能。

关键词：伪随机码脉冲引信抗嗓性能相关函数