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Research on resolution between multi-component LFM signals in the fractional Fourier domain

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Science china(Information Sciences) 2012年第6期55卷 1301-1312页

作者： LIU Feng 1,XU HuiFa 1,2,TAO Ran 3.& WANG Yue 3.1 Department of Electronic and Information engineering,naval aeronautical engineering Institute,Yantai 264001,china 2 The 943.2 th Unit of People's Liberation Army,qingdao 266111,china 3.School of Information Science and Technology,Beijing Institute of Technology,Beijing 100081,china 1. Department of Electronic and Information engineering Naval Aeronautical Engineering Institute Yantai 264001 China2. The 94362th Unit of People’s Liberation Army Qingdao 266111 China3. School of Information Science and Technology Beijing Institute of Technology Beijing 100081 China

When the initial frequencies and chirp rates of multi-component linear frequency modulation (LFM or chirp) signals are close,the signals may not be distinguished in the fractional Fourier domain (FRFD).Consequently,some signals cannot be *** this paper,first,the spectral distribution characteristics of a continuous LFM signal in the FRFD are analyzed,and then the spectral distribution characteristics of a LFM signal in the discrete FRFD are ***,the critical resolution distance between the peaks of two LFM signals in the FRFD is deduced,and the relationship between the dimensional normalization parameter and the distance between two LFM signals in the FRFD is also *** is discovered that selecting a proper dimensional normalization parameter can increase the ***,a method to select the parameter is proposed,which can improve the resolution ability of the fractional Fourier transform (FRFT).Its effectiveness is verified by simulation results.

关键词： fractional Fourier transform LFM signal signal resolution

The Design and Implement of Fleet F77 Station’s Simulator

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The Design and Implement of Fleet F77 Station’s Simulator

2010 2nd International Conference on Information and Multimedia Technology(ICIMT 2010)

作者： Xu JinJun naval aeronautical engineering Institute {3. branch {3. Shandong china 266041

In this paper,we introduced the main technology and method to develop marine F77 station’s simulator with Flash software,Flash Media Server（FMS）and XML（eXtensible Markup Language） *** this paper,we can find that ... 详细信息

关键词： Flash FMS XML GMDSS Simulator F77 Station

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无人机全局渐近稳定自动编队飞行控制研究

系统仿真学报 2009年第7期21卷 2014-2017页

作者：王正朱兴动海军航空工程学院青岛分院青岛266041

研究了无人机在"长机-僚机"编队结构中僚机的编队保持自动驾驶仪控制算法。首先提出了一个基于两机相对位置动力学的控制算法,但该算法在状态空间中存在奇异点,因此又提出了一个在惯性坐标系中基于新的误差形式的无奇异点的编队控制算... 详细信息

研究了无人机在"长机-僚机"编队结构中僚机的编队保持自动驾驶仪控制算法。首先提出了一个基于两机相对位置动力学的控制算法,但该算法在状态空间中存在奇异点,因此又提出了一个在惯性坐标系中基于新的误差形式的无奇异点的编队控制算法。最后证明了该算法在整个状态空间中的全局渐近稳定性并进行了数值模拟,说明该控制算法具有较好的性能。

关键词：编队飞行无人机全局渐近稳定编队保持自动驾驶仪

Time-Lag Effect on the Capture Capability of Pursuit-Control

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Time-Lag Effect on the Capture Capability of Pursuit-Control

应用统计法计算主动攻击水雷命中概率的仿真研究

第二十六届中国控制会议

作者： Wu Wenhai1,Qu Jianling2 1.naval aeronautical engineering Academy {3. branch,{3. 266041,P.R.china2.naval aeronautical engineering Academy {3. branch,{3. 266041,P.R.china

The time-lag problem is one of the most important problems in both the fields of mathematics and *** many research results have been presented,under the effect of control-lag,there are no any related report on such topics in the pursuit-evasion problem,to the best knowledge of *** may be for the reason that the dynamic equations of the pursuit-evasion system are too complex to solve ***,there are only some research reports on the study of its capture capability based on idea assumptions,without consideration of any time lag of pursuit control.A new study method on the capture capability is presented in this paper,under the effect of ***,the no-time-lag theoretical results of PPN are validated by simulation,which not only demonstrates the correctness of theorem but also indicates the validity of the system modeling and simulation *** based on the modeling system with different control lag times,some useful results on pursuit control time-lag are drawn from the simulation of two different aspects,effect on capture probability and pursuit *** lag effect on short-distance pursuit is greater than long-distance pursuit,if the ratio of the pursuer velocity to target velocity （VROPT） is constant: ① When the initial relative distance is more than 10 km,the capturability decreases less than 5% compared to that without time lag,even if with a time lag up to 3.seconds during the given pursuit-evasion states.② While the initial distance is less than 3.m,if the lag time is up to 3. it decreases about 50%.③ The capture capability is almost unchanged if the control-lag is no more than 0.5 *** also show that the effect on the pursuit-evasion process is *** the constant time lag,VROPT has effect on the *** show that the capturability is improved as the increase of the ***,the pursuit lag time has negative effect on the capturability,especially during short-d

关键词： Simulation Pursuit Capture Set Time Lag Navigation-Interception Capture Capability

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系统仿真学报 2000年第6期12卷 678-680页

作者：孙明太王涛韩强海军航空工程学院青岛分院! 青岛 266041

在简要介绍主动攻击水雷工作过程的基础上，详细介绍了用统计法仿真计算主动攻击水雷命中概率的原理、方法、步骤，并给出了计算机仿真结果。

关键词：主动攻击水雷命中概率统计法

Noise reduction method for nonlinear signal based on maximum variance unfolding and its application to fault diagnosis

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Science china(Technological Sciences) 2010年第8期53卷 2122-2128页

作者： ZHANG Yun &LI BenWei Department of Airborne Vehicle engineering,naval aeronautical engineering Institute,Yantai 264001,china 1. Department of Airborne Vehicle engineering Naval Aeronautical Engineering Institute Yantai 264001 China

A new noise reduction method for nonlinear signal based on maximum variance unfolding(MVU)is *** noisy sig- nal is firstly embedded into a high-dimensional phase space based on phase space reconstruction theory,and then the manifold learning algorithm MVU is used to perform nonlinear dimensionality reduction on the data of phase space in order to separate low-dimensional manifold representing the attractor from noise ***,the noise-reduced signal is obtained through reconstructing the low-dimensional *** simulation results of Lorenz system show that the proposed MVU-based noise reduction method outperforms the KPCA-based method and has the advantages of simple parameter estimation and low parameter *** proposed method is applied to fault detection of a vibration signal from rotor-stator of aero engine with slight rubbing *** denoised results show that the slight rubbing features overwhelmed by noise can be effectively extracted by the proposed noise reduction method.

关键词： nonlinear noise reduction manifold learning maximum variance unfolding fault diagnosis

TiO_2-SnO_2纳米粒子超声波光催化降解尤丽特蓝的动力学研究

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太阳能学报 2010年第3期31卷 286-290页

作者：暴勇超李小丽刘娟赵春禄青岛科技大学环境与安全工程学院青岛266042 海军航空工程学院青岛分院航空机械系青岛266041

采用溶胶-凝胶法制备了TiO_2-SnO_2催化剂,以尤丽特蓝为研究对象,研究了超声波光催化降解尤丽特蓝的动力学。结果表明:在所研究的范围内,SnO_2的最佳掺杂量为0.05,TiO_2-SnO_2催化剂的最佳投加量为2g/L;超声波光催化降解尤丽特蓝符合一... 详细信息

采用溶胶-凝胶法制备了TiO_2-SnO_2催化剂,以尤丽特蓝为研究对象,研究了超声波光催化降解尤丽特蓝的动力学。结果表明:在所研究的范围内,SnO_2的最佳掺杂量为0.05,TiO_2-SnO_2催化剂的最佳投加量为2g/L;超声波光催化降解尤丽特蓝符合一级动力学反应,可用L-H动力学方程描述,且反应速率常数K∝C_0^(0.85)·(DO)^(3.91);超声光催化协同降解要比单独超声波或光催化处理效果显著,证实了声光联合技术具有明显的协同效应。

关键词： TiO2-SnO2超声波光催化动力学协同效应

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聚氨酯/环氧树脂互穿网络硬泡循环压缩

上海交通大学学报 2010年第11期44卷 1610-1614页

作者：花兴艳赵培仲朱金华王源升中国人民解放军91550部队94分队海军航空工程学院青岛分院海军工程大学理学院

制备了聚氨酯(PU)/环氧树脂(ER)互穿聚合物网络硬泡,研究了互穿聚合物网络(IPN)硬泡的化学结构及微观结构形态.傅里叶红外光谱(FTIR)分析表明,IPN硬泡的网络间存在接枝反应.扫描电子显微镜(SEM)分析发现,IPN硬泡泡孔结构形状都比较均一... 详细信息

制备了聚氨酯(PU)/环氧树脂(ER)互穿聚合物网络硬泡,研究了互穿聚合物网络(IPN)硬泡的化学结构及微观结构形态.傅里叶红外光谱(FTIR)分析表明,IPN硬泡的网络间存在接枝反应.扫描电子显微镜(SEM)分析发现,IPN硬泡泡孔结构形状都比较均一.循环压缩实验研究表明:随循环次数增加,应力下降,单次循环的能量损耗下降;随ER含量增加,IPN硬泡的压缩模量和强度提高,相同应变下应力增加,每次循环耗能增加;循环压缩的加卸载应力-应变曲线可用改进的Ogden模型表示;累积能量损耗可用Weibull方程表示.

关键词：聚氨酯/环氧树脂互穿聚合物网络硬泡循环压缩能量损耗

Optimal Training Design and Placement for MIMO Orthogonal Frequency Division Multiplexing Channel Estimation

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Journal of Shanghai Jiaotong university(Science) 2010年第1期15卷 58-63页

作者：林成裕钱良张文军徐友云李洪烈 Institute of Image Communication and Information Processing Shanghai Jiaotong University Shanghai Key Laboratory of Digital Media Processing and Transmissions Shanghai Jiaotong University qingdao branch of naval {3. engineering Institute

This paper deals with optimal training design and placement over multiple orthogonal frequency division multiplexing(OFDM) symbols for the least squares(LS) channel estimation in multiple-input multipleoutput(MIMO) OFDM ***,the optimal pilot sequences over multiple OFDM symbols are derived by co-cyclic Jacket matrices based on the minimum mean square error(MSE) of the LS channel ***,an enhanced channel estimation method using sliding window is proposed to improve further the performance for the optimal pilot sequences in fast-varying *** results show that the enhancedmethod can efficiently improve the performances for the optimal pilot sequences over two and four OFDM symbols,especially in fast-varying channels.

关键词： co-cyclic Jacket matrix optimal pilot sequences channel estimation multiple-input multiple-output orthogonal frequency division multiplexing (MIMO-OFDM)