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Research on Modulation Signal Denoising Method Based on Improved Variational Mode Decomposition
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作者 Canyu Mo Qianqiang Lin +1 位作者 Yuanduo Niu Haoran Du 《Journal of Electronic Research and Application》 2024年第1期7-15,共9页
In order to further analyze the micro-motion modulation signals generated by rotating components and extract micro-motion features,a modulation signal denoising algorithm based on improved variational mode decompositi... In order to further analyze the micro-motion modulation signals generated by rotating components and extract micro-motion features,a modulation signal denoising algorithm based on improved variational mode decomposition(VMD)is proposed.To improve the time-frequency performance,this method decomposes the data into narrowband signals and analyzes the internal energy and frequency variations within the signal.Genetic algorithms are used to adaptively optimize the mode number and bandwidth control parameters in the process of VMD.This approach aims to obtain the optimal parameter combination and perform mode decomposition on the micro-motion modulation signal.The optimal mode number and quadratic penalty factor for VMD are determined.Based on the optimal values of the mode number and quadratic penalty factor,the original signal is decomposed using VMD,resulting in optimal mode number intrinsic mode function(IMF)components.The effective modes are then reconstructed with the denoised modes,achieving signal denoising.Through experimental data verification,the proposed algorithm demonstrates effective denoising of modulation signals.In simulation data validation,the algorithm achieves the highest signal-to-noise ratio(SNR)and exhibits the best performance. 展开更多
关键词 Micro-motion modulation signal Variational mode decomposition Genetic algorithm Adaptive optimization
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Research on Failure Occurred During Switching in Bypass Pair of Valve Base Electronics for Converter Station
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作者 Chen Zhengguang Tang Guangfu Wei Xiaoguang Chen Longlong 《Electricity》 2012年第4期53-54,共2页
In the paper “Research on Failure Occurred During Switching in Bypass Pair of Valve Base Electronics for Yulong Converter Station,”the author proposed a control strategy based on shortest job first algorithm.Shortes... In the paper “Research on Failure Occurred During Switching in Bypass Pair of Valve Base Electronics for Yulong Converter Station,”the author proposed a control strategy based on shortest job first algorithm.Shortest job first algorithm effectively avoids the false triggering that appears due to the time delay procreated in pulse frequency conversion when the switching-in of bypass pair is finished.The core idea of the control strategy is as follows:when the operation of switching-in of bypass pair is finished,the signal frequency,whether 10 kHz or 1 MHz,is not directly detected,but in the program it is previously regarded. 展开更多
关键词 换流站 旁路 故障 电子 切换 开关过程 优先算法
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Exploring Sequential Feature Selection in Deep Bi-LSTM Models for Speech Emotion Recognition
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作者 Fatma Harby Mansor Alohali +1 位作者 Adel Thaljaoui Amira Samy Talaat 《Computers, Materials & Continua》 SCIE EI 2024年第2期2689-2719,共31页
Machine Learning(ML)algorithms play a pivotal role in Speech Emotion Recognition(SER),although they encounter a formidable obstacle in accurately discerning a speaker’s emotional state.The examination of the emotiona... Machine Learning(ML)algorithms play a pivotal role in Speech Emotion Recognition(SER),although they encounter a formidable obstacle in accurately discerning a speaker’s emotional state.The examination of the emotional states of speakers holds significant importance in a range of real-time applications,including but not limited to virtual reality,human-robot interaction,emergency centers,and human behavior assessment.Accurately identifying emotions in the SER process relies on extracting relevant information from audio inputs.Previous studies on SER have predominantly utilized short-time characteristics such as Mel Frequency Cepstral Coefficients(MFCCs)due to their ability to capture the periodic nature of audio signals effectively.Although these traits may improve their ability to perceive and interpret emotional depictions appropriately,MFCCS has some limitations.So this study aims to tackle the aforementioned issue by systematically picking multiple audio cues,enhancing the classifier model’s efficacy in accurately discerning human emotions.The utilized dataset is taken from the EMO-DB database,preprocessing input speech is done using a 2D Convolution Neural Network(CNN)involves applying convolutional operations to spectrograms as they afford a visual representation of the way the audio signal frequency content changes over time.The next step is the spectrogram data normalization which is crucial for Neural Network(NN)training as it aids in faster convergence.Then the five auditory features MFCCs,Chroma,Mel-Spectrogram,Contrast,and Tonnetz are extracted from the spectrogram sequentially.The attitude of feature selection is to retain only dominant features by excluding the irrelevant ones.In this paper,the Sequential Forward Selection(SFS)and Sequential Backward Selection(SBS)techniques were employed for multiple audio cues features selection.Finally,the feature sets composed from the hybrid feature extraction methods are fed into the deep Bidirectional Long Short Term Memory(Bi-LSTM)network to discern emotions.Since the deep Bi-LSTM can hierarchically learn complex features and increases model capacity by achieving more robust temporal modeling,it is more effective than a shallow Bi-LSTM in capturing the intricate tones of emotional content existent in speech signals.The effectiveness and resilience of the proposed SER model were evaluated by experiments,comparing it to state-of-the-art SER techniques.The results indicated that the model achieved accuracy rates of 90.92%,93%,and 92%over the Ryerson Audio-Visual Database of Emotional Speech and Song(RAVDESS),Berlin Database of Emotional Speech(EMO-DB),and The Interactive Emotional Dyadic Motion Capture(IEMOCAP)datasets,respectively.These findings signify a prominent enhancement in the ability to emotional depictions identification in speech,showcasing the potential of the proposed model in advancing the SER field. 展开更多
关键词 Artificial intelligence application multi features sequential selection speech emotion recognition deep Bi-LSTM
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Persymmetric adaptive polarimetric detection of subspace range-spread targets in compound Gaussian sea clutter
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作者 XU Shuwen HAO Yifan +1 位作者 WANG Zhuo XUE Jian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期31-42,共12页
This paper focuses on the adaptive detection of range and Doppler dual-spread targets in non-homogeneous and nonGaussian sea clutter.The sea clutter from two polarimetric channels is modeled as a compound-Gaussian mod... This paper focuses on the adaptive detection of range and Doppler dual-spread targets in non-homogeneous and nonGaussian sea clutter.The sea clutter from two polarimetric channels is modeled as a compound-Gaussian model with different parameters,and the target is modeled as a subspace rangespread target model.The persymmetric structure is used to model the clutter covariance matrix,in order to reduce the reliance on secondary data of the designed detectors.Three adaptive polarimetric persymmetric detectors are designed based on the generalized likelihood ratio test(GLRT),Rao test,and Wald test.All the proposed detectors have constant falsealarm rate property with respect to the clutter texture,the speckle covariance matrix.Experimental results on simulated and measured data show that three adaptive detectors outperform the competitors in different clutter environments,and the proposed GLRT detector has the best detection performance under different parameters. 展开更多
关键词 sea clutter adaptive polarimetric detection compound Gaussian model subspace range-spread target persymmetric structure
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Research on variable block size motion estimation algorithm for airborne image
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作者 王科 Huang Dongshan +1 位作者 Ma Li Zhang Yudong 《High Technology Letters》 EI CAS 2014年第3期321-327,共7页
A fast motion estimation algorithm for variable block-size using the "line scan and block merge procedure" is proposed for airborne image compression modules.Full hardware implementation via FPGA is discusse... A fast motion estimation algorithm for variable block-size using the "line scan and block merge procedure" is proposed for airborne image compression modules.Full hardware implementation via FPGA is discussed in detail.The proposed pipelined architecture based on the line scan algorithm is capable of calculating the required 41 motion vectors of various size blocks supported by H.264 within a 16 X 16 block in parallel.An adaptive rate distortion cost function is used for various size block decision.The motion vectors of adjacent small blocks are merged to predict the motion vectors of larger blocks for reducing computation.Experimental results show that our proposed method has lower computational complexity than full search algorithm with slight quality decrease and little bit rate increase.Due to the high real-time processing speed it can be easily realized in hardware. 展开更多
关键词 快速运动估计算法 图像压缩 机载 可变 运动矢量 流水线结构 计算复杂度 全搜索算法
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Research and Application on IT Standards System of SGCC
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作者 Yang Huafei Cui Hua Hu Quangui 《China Standardization》 2011年第4期55-58,共4页
关于为中国(SGCC ) 的州的格子公司的 informatization 的 SG186 工程,主要试图造一“垂直突破,水平集成”在企业水平并且到的信息集成的站台开始造一个 digitization 力量网络和一家 informatization 企业; informatization 标准系... 关于为中国(SGCC ) 的州的格子公司的 informatization 的 SG186 工程,主要试图造一“垂直突破,水平集成”在企业水平并且到的信息集成的站台开始造一个 digitization 力量网络和一家 informatization 企业; informatization 标准系统是重要保证因素之一完全完成 SG186 工程以及为 systems.This 文章与当前的研究的简短介绍首先为 informatization 标准系统的建立分析了必要性的存在信息的全部采纳和集成提供基本条件标准系统和锁环的 Identification-Execution-Check (录制) 展开更多
关键词 信息化标准体系 国家电网公司 应用 信息化企业 IT SGCC 集成平台 信息系统
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Adaptive Gain Tuning Rule for Nonlinear Sliding-mode Speed Control of Encoderless Three-phase Permanent Magnet Assisted Synchronous Motor 被引量:1
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作者 Ghada A.Abdel Aziz Rehan Ali Khan 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第3期301-310,共10页
In this paper, an adaptive gain tuning rule is designed for the nonlinear sliding mode speed control(NSMSC) in order to enhance the dynamic performance and the robustness of the permanent magnet assisted synchronous r... In this paper, an adaptive gain tuning rule is designed for the nonlinear sliding mode speed control(NSMSC) in order to enhance the dynamic performance and the robustness of the permanent magnet assisted synchronous reluctance motor(PMa-Syn RM) with considering the parameter uncertainties. A nonlinear sliding surface whose parameters are altering with time is designed at first. The proposed NSMSC can minimize the settling time without any overshoot via utilizing a low damping ratio at starting along with a high damping ratio as the output approaches the target set-point. In addition, it eliminates the problem of the singularity with the upper bound of an uncertain term that is hard to be measured practically as well as ensures a rapid convergence in finite time, through employing a simple adaptation law. Moreover, for enhancing the system efficiency throughout the constant torque region, the control system utilizes the maximum torque per ampere technique. The nonlinear sliding surface stability is assured via employing Lyapunov stability theory. Furthermore, a simple sliding mode estimator is employed for estimating the system uncertainties. The stability analysis and the experimental results indicate the effectiveness along with feasibility of the proposed speed estimation and the NSMSC approach for a 1.1-k W PMa-Syn RM under different speed references, electrical and mechanical parameters disparities, and load disturbance conditions. 展开更多
关键词 Permanent magnet assisted synchronous reluctance motor Nonlinear sliding mode speed control Speed estimation Parameter uncertainties Sliding mode estimator
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Deinterleaving of radar pulse based on implicit feature
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作者 GUO Qiang TENG Long +2 位作者 WU Xinliang QI Liangang SONG Wenming 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1537-1549,共13页
In the complex countermeasure environment,the pulse description words(PDWs)of the same type of multi-function radar emitters are similar in multiple dimensions.Therefore,it is difficult for conventional methods to dei... In the complex countermeasure environment,the pulse description words(PDWs)of the same type of multi-function radar emitters are similar in multiple dimensions.Therefore,it is difficult for conventional methods to deinterleave such emitters.In order to solve this problem,a pulse deinterleaving method based on implicit features is proposed in this paper.The proposed method introduces long short-term memory(LSTM)neural networks and statistical analysis to mine new features from similar PDW features,that is,the variation law(implicit features)of pulse sequences of different radiation sources over time.The multi-function radar emitter is deinterleaved based on the pulse sequence variation law.Statistical results show that the proposed method not only achieves satisfactory performance,but also has good robustness. 展开更多
关键词 multi-functional radars of the same type pulse deinterleaving pulse amplitude implicit feature long short-term memory(LSTM)neural networks.
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Cuckoo search algorithm-based optimal deployment method of heterogeneous multistatic radar for barrier coverage
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作者 LI Haipeng FENG Dazheng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1101-1115,共15页
This paper proposes an optimal deployment method of heterogeneous multistatic radars to construct arc barrier coverage with location restrictions.This method analyzes and proves the properties of different deployment ... This paper proposes an optimal deployment method of heterogeneous multistatic radars to construct arc barrier coverage with location restrictions.This method analyzes and proves the properties of different deployment patterns in the optimal deployment sequence.Based on these properties and considering location restrictions,it introduces an optimization model of arc barrier coverage and aims to minimize the total deployment cost of heterogeneous multistatic radars.To overcome the non-convexity of the model and the non-analytical nature of the objective function,an algorithm combining integer line programming and the cuckoo search algorithm(CSA)is proposed.The proposed algorithm can determine the number of receivers and transmitters in each optimal deployment squence to minimize the total placement cost.Simulations are conducted in different conditions to verify the effectiveness of the proposed method. 展开更多
关键词 heterogeneous multistatic radar(HMR) arc barrier coverage minimum deployment cost optimal deployment sequence cuckoo search algorithm(CSA)
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Optimization method of linear barrier coverage deployment for multistatic radar
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作者 LI Haipeng FENG Dazheng WANG Xiaohui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期68-80,共13页
To address the problem of building linear barrier coverage with the location restriction, an optimization method for deploying multistatic radars is proposed, where the location restriction splits the deployment line ... To address the problem of building linear barrier coverage with the location restriction, an optimization method for deploying multistatic radars is proposed, where the location restriction splits the deployment line into two segments. By proving the characteristics of deployment patterns, an optimal deployment sequence consisting of multiple deployment patterns is proposed and exploited to cover each segment. The types and numbers of deployment patterns are determined by an algorithm that combines the integer linear programming(ILP)and exhaustive method(EM). In addition, to reduce the computation amount, a formula is introduced to calculate the upper threshold of receivers’ number in a deployment pattern. Furthermore, since the objective function is non-convex and non-analytic, the overall model is divided into two layers concerning two suboptimization problems. Subsequently, another algorithm that integrates the segments and layers is proposed to determine the deployment parameters, such as the minimum cost, parameters of the optimal deployment sequence, and the location of the split point. Simulation results demonstrate that the proposed method can effectively determine the optimal deployment parameters under the location restriction. 展开更多
关键词 multistatic radar linear barrier coverage minimum deployment cost deployment sequence wireless sensor networks(WSNs)
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Encoderless Five-phase PMa-SynRM Drive System Based on Robust Torque-speed Estimator with Super-twisting Sliding Mode Control
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作者 Ghada A.Abdel Aziz Rehan Ali Khan 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第1期54-62,共9页
In this paper,a robust torque speed estimator(RTSE)for linear parameter changing(LPC)system is proposed and designed for an encoderless five-phase permanent magnet assisted synchronous reluctance motor(5-phase PMa-Syn... In this paper,a robust torque speed estimator(RTSE)for linear parameter changing(LPC)system is proposed and designed for an encoderless five-phase permanent magnet assisted synchronous reluctance motor(5-phase PMa-SynRM).This estimator is utilized for estimating the rotor speed and the load torque as well as can solve the speed sensor fault problem,as the feedback speed information is obtained directly from the virtual sensor.In addition,this technique is able to enhance the 5-phase PMa-SynRM performance by estimating the load torque for the real time compensation.The stability analysis of the proposed estimator is performed via Schur complement along with Lyapunov analysis.Furthermore,for improving the 5-phase PMa-SynRM performance,five super-twisting sliding mode controllers(ST-SMCs)are employed with providing a robust response without the impacts of high chattering problem.A super-twisting sliding mode speed controller(ST-SMSC)is employed for controlling the PMa-SynRM rotor speed,and four super-twisting sliding mode current controllers(ST-SMCCs)are employed for controlling the 5-phase PMa-SynRM currents.The stability analysis and the experimental results indicate the effectiveness along with feasibility of the proposed RTSE and the ST-SMSC with ST-SMCCs approach for a 750-W 5-phase PMa-SynRM under load disturbance,parameters variations,single open-phase fault,and adjacent two-phase open circuit fault conditions. 展开更多
关键词 Five-phase permanent magnet assisted synchronous reluctance motor Encoderless control Supertwisting sliding mode control Torque-speed estimator
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Efficient Hardware Design of a Secure Cancellable Biometric Cryptosystem
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作者 Lamiaa A.Abou Elazm Walid El-Shafai +6 位作者 Sameh Ibrahim Mohamed G.Egila H.Shawkey Mohamed K.H.Elsaid Naglaa F.Soliman Hussah Nasser AlEisa Fathi E.Abd El-Samie 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期929-955,共27页
Biometric security is a growing trend,as it supports the authentication of persons using confidential biometric data.Most of the transmitted data in multi-media systems are susceptible to attacks,which affect the secur... Biometric security is a growing trend,as it supports the authentication of persons using confidential biometric data.Most of the transmitted data in multi-media systems are susceptible to attacks,which affect the security of these sys-tems.Biometric systems provide sufficient protection and privacy for users.The recently-introduced cancellable biometric recognition systems have not been investigated in the presence of different types of attacks.In addition,they have not been studied on different and large biometric datasets.Another point that deserves consideration is the hardware implementation of cancellable biometric recognition systems.This paper presents a suggested hybrid cancellable biometric recognition system based on a 3D chaotic cryptosystem.The rationale behind the utilization of the 3D chaotic cryptosystem is to guarantee strong encryption of biometric templates,and hence enhance the security and privacy of users.The suggested cryptosystem adds significant permutation and diffusion to the encrypted biometric templates.We introduce some sort of attack analysis in this paper to prove the robustness of the proposed cryptosystem against attacks.In addition,a Field Programmable Gate Array(FPGA)implementation of the pro-posed system is introduced.The obtained results with the proposed cryptosystem are compared with those of the traditional encryption schemes,such as Double Random Phase Encoding(DRPE)to reveal superiority,and hence high recogni-tion performance of the proposed cancellable biometric recognition system.The obtained results prove that the proposed cryptosystem enhances the security and leads to better efficiency of the cancellable biometric recognition system in the presence of different types of attacks. 展开更多
关键词 Information security cancellable biometric recognition systems CRYPTANALYSIS 3D chaotic map ENCRYPTION FPGA
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Manoeuvre decision-making of unmanned aerial vehicles in air combat based on an expert actor-based soft actor critic algorithm
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作者 Bo Li Shuangxia Bai +3 位作者 Shiyang Liang Rui Ma Evgeny Neretin Jingyi Huang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第4期1608-1619,共12页
The demand for autonomous motion control of unmanned aerial vehicles in air combat is boosted as taking the initiative in combat appears more and more crucial.Unmanned aerial vehicles inability to manoeuvre autonomous... The demand for autonomous motion control of unmanned aerial vehicles in air combat is boosted as taking the initiative in combat appears more and more crucial.Unmanned aerial vehicles inability to manoeuvre autonomously during air combat that features highly dynamic and uncertain manoeuvres of the enemy;however,limits their combat capabilities,which proves to be very challenging.To meet the challenge,this article proposes an autonomous manoeuvre decision model using an expert actor-based soft actor critic algorithm that reconstructs empirical replay buffer with expert experience.Specifically,the algorithm uses a small amount of expert experience to increase the diversity of the samples,which can largely improve the exploration and utilisation efficiency of deep reinforcement learning.And to simulate the complex battlefield environment,a one-toone air combat model is established and the concept of missile's attack region is introduced.The model enables the one-to-one air combat to be simulated under different initial battlefield situations.Simulation results show that the expert actor-based soft actor critic algorithm can find the most favourable policy for unmanned aerial vehicles to defeat the opponent faster,and converge more quickly,compared with the soft actor critic algorithm. 展开更多
关键词 artificial intelligence techniques autonomous drone deep neural networks
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双官能团界面改性剂对WPC综合性能的影响 被引量:2
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作者 李腊梅 李凯夫 +2 位作者 云虹 姜涛 林溪顺 《林产工业》 北大核心 2016年第1期32-35,共4页
采用新型双官能团偶联剂对木粉进行表面处理,并通过单因素法研究偶联剂种类和含量对材料综合性能的影响,并结合扫描电镜进行了微观形貌分析。结果表明:新型双官能团偶联剂有优于传统偶联剂的改性效果。当添加量为0.8%时,木粉与PVC树脂... 采用新型双官能团偶联剂对木粉进行表面处理,并通过单因素法研究偶联剂种类和含量对材料综合性能的影响,并结合扫描电镜进行了微观形貌分析。结果表明:新型双官能团偶联剂有优于传统偶联剂的改性效果。当添加量为0.8%时,木粉与PVC树脂相容性达到较理想状态,抗弯强度、抗弯弹性模量、冲击韧性和拉伸强度达到最佳值,分别为35.76MPa,2 378.32MPa,1 5.08kJ/m^2,14.01MPa。 展开更多
关键词 木塑复合材料 界面相容 力学性能
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无镍高氮奥氏体不锈钢的脆韧转变 被引量:2
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作者 M.Tanaka T.Onomoto +2 位作者 T.Tsuchiyama K.Higashida 顾剑锋 《热处理》 CAS 2014年第5期63-66,共4页
研究了无镍高氮奥氏体不锈钢的脆韧转变(BDT)。在176 K、273 K和336 K进行的落锤试验结果表明,尽管Fe-25Cr-1.1N(质量分数,%)是面心立方结构的奥氏体合金钢,但仍展现出显著的脆韧转变现象。对冲击试验试样的塑性变形观察表明,BDT是由于... 研究了无镍高氮奥氏体不锈钢的脆韧转变(BDT)。在176 K、273 K和336 K进行的落锤试验结果表明,尽管Fe-25Cr-1.1N(质量分数,%)是面心立方结构的奥氏体合金钢,但仍展现出显著的脆韧转变现象。对冲击试验试样的塑性变形观察表明,BDT是由于低温下差的延展性所致,这与铁素体钢的情况是一致的。为了测量BDT的激活能,利用4点弯曲试验研究了应变速率与BDT温度的关系。研究发现,BDT温度与应变速率之间的依赖关系不显著,且BDT温度对应变率的Arrhenius曲线表明Fe-25Cr-1.1N钢BDT的激活能比低碳铁素体钢的高得多。从滑移位错与溶质氮原子发生交互作用导致低温下位错可动性降低这一角度,本文探讨了高氮钢特有的BDT及其高激活能的本质原因。 展开更多
关键词 脆韧转变 位错 断裂 激活能 位错迁移率
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Contourlet transform for image fusion using cycle spinning 被引量:9
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作者 Kun Liu Lei Guo Jingsong Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期353-357,共5页
A new method for image fusion based on Contourlet transform and cycle spinning is proposed. Contourlet transform is a flexible multiresolution, local and directional image expansion, also provids a sparse representati... A new method for image fusion based on Contourlet transform and cycle spinning is proposed. Contourlet transform is a flexible multiresolution, local and directional image expansion, also provids a sparse representation for two-dimensional piece-wise smooth signals resembling images. Due to lack of translation invariance property in Contourlet transform, the conventional image fusion algorithm based on Contourlet transform introduces many artifacts. According to the theory of cycle spinning applied to image denoising, an invariance transform can reduce the artifacts through a series of processing efficiently. So the technology of cycle spinning is introduced to develop the translation invariant Contourlet fusion algorithm. This method can effectively eliminate the Gibbs-like phenomenon, extract the characteristics of original images, and preserve more important information. Experimental results show the simplicity and effectiveness of the method and its advantages over the conventional approaches. 展开更多
关键词 image processing image fusion Contourlet transform cycle spinning.
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Switching variability index based multiple strategy CFAR detector 被引量:4
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作者 Yang Li Zhenyuan Ji +1 位作者 Bingfei Li Gil Alterovitz 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期580-587,共8页
A switching variability index (SVl) constant false alarm rate (CFAR) detector is proposed for improving the detection performance of VI-CFAR detectors in multiple targets backgrounds. When the presence of non-homo... A switching variability index (SVl) constant false alarm rate (CFAR) detector is proposed for improving the detection performance of VI-CFAR detectors in multiple targets backgrounds. When the presence of non-homogeneity in CFAR reference windows is indicated by a VI-CFAR detector, a switching- CFAR detector is introduced to optimize the performance of the VI-CFAR detector in homogeneous, multiple targets and clutter edge backgrounds. The structure and parameters selection method of the SVI-CFAR detector is presented. Comparisons with classic CFAR detectors and recently proposed detectors are also given. Theoretical analysis and simulation results show that SVICFAR detector maintains the good performance of the VI-CFAR detector in homogeneous and clutter edge backgrounds, while greatly improving the capacity of anti-multi targets. 展开更多
关键词 switching variability index constant false alarm rate(SVI-CFAR) adaptive detection complex environment multiple-strategy detection radar target detection.
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Multi-target Collaborative Combat Decision-Making by Improved Particle Swarm Optimizer 被引量:4
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作者 Ding Yongfei Yang Liuqing +2 位作者 Hou Jianyong Jin Guting Zhen Ziyang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第1期181-187,共7页
A decision-making problem of missile-target assignment with a novel particle swarm optimization algorithm is proposed when it comes to a multiple target collaborative combat situation.The threat function is establishe... A decision-making problem of missile-target assignment with a novel particle swarm optimization algorithm is proposed when it comes to a multiple target collaborative combat situation.The threat function is established to describe air combat situation.Optimization function is used to find an optimal missile-target assignment.An improved particle swarm optimization algorithm is utilized to figure out the optimization function with less parameters,which is based on the adaptive random learning approach.According to the coordinated attack tactics,there are some adjustments to the assignment.Simulation example results show that it is an effective algorithm to handle with the decision-making problem of the missile-target assignment(MTA)in air combat. 展开更多
关键词 COLLABORATIVE COMBAT MULTI-TARGET DECISION-MAKING IMPROVED particle swarm optimization
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Distributed Cooperative Control Algorithm for Multi-UAV Mission Rendezvous 被引量:5
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作者 Liu Guoliang Xing Dongjing +2 位作者 Hou Jianyong Jin Guting Zhen Ziyang 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第6期617-626,共10页
Multiple unmanned aerial vehicles(UAVs)cooperative operation is the main form for UAVs fighting in battlefield,and multi-UAV mission rendezvous is the premise of cooperative reconnaissance and attack missions.We propo... Multiple unmanned aerial vehicles(UAVs)cooperative operation is the main form for UAVs fighting in battlefield,and multi-UAV mission rendezvous is the premise of cooperative reconnaissance and attack missions.We propose a rendezvous control strategy,which divides the rendezvous process into two parts:The loose formation rendezvous and the close formation rendezvous.In the first stage,UAVs are supposed to reach the specific target locations simultaneously and form a loose formation.A distributed control strategy based on first-order consensus algorithm is presented to achieve this goal.Then the second stage is designed based on the second-order consensus algorithm to complete the transition from the loose formation to the close formation.This process needs the speeds and heading angles of UAVs to reach an agreement.Besides,control algorithms with a virtual leader are proposed,by which the formation states can reach a specific value.Finally,simulation results show that the control algorithms are capable of realizing the mission rendezvous of multi-UAV and the consistence of UAVs′final states,which verify the effectiveness and feasibility of the designed control strategy. 展开更多
关键词 unmanned aerial vehicles loose formation rendezvous close formation rendezvous consensus algorithm cooperative control
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Optimized analysis of sharpening characteristics of a compact RF pulse source based on a gyro-magnetic nonlinear transmission line for ultrawideband electromagnetic pulse application 被引量:3
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作者 铁维昊 孟萃 +4 位作者 赵程光 鲁小刚 谢军 蒋丹 闫自让 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第9期110-121,共12页
We constructed a compact high-power RF pulse generator based on a gyro-magnetic nonlinear transmission line(GNLTL) to produce a high-voltage pulse with a sub-nanosecond rise time and a relatively high repetition rate,... We constructed a compact high-power RF pulse generator based on a gyro-magnetic nonlinear transmission line(GNLTL) to produce a high-voltage pulse with a sub-nanosecond rise time and a relatively high repetition rate, which shows great potential for application in the high-power ultrawideband electromagnetic effect, etc. The influence of incident pulse parameters(rise time and voltage amplitude) and line length on the sharpening characteristics of the GNLTL were investigated experimentally to optimize the rising rate of the modulated pulse front. Based on the GNLTL equivalent circuit model consisting of an LC ladder network, the rise time, the voltage conversion coefficient and the rising rate properties of a modulated pulse were also numerically analyzed in a wider range. The results show that a?>?90 k V RF pulse with a rise time of 350 ps and a repetition rate of 1 kHz in burst mode is produced by the GNLTL at an axial biasing magnetic field of 22 kA m^-1 and a line length of 30 cm under the condition of a 70 kV incident pulse. Applying a faster and higher incident pulse is conducive to improving the sharpening effect of the GNLTL. Furthermore, within a certain range, increasing the line length of the GNLTL not only reduces the rise time, but increases the voltage conversion coefficient and the rising rate of a modulated pulse. Furthermore, considering the energy loss of ferrite rings, there is an optimal line length to obtain the fastest rising rate of a modulated pulse front edge. 展开更多
关键词 gyro-magnetic nonlinear transmission line (GNLTL) SHARPENING CHARACTERISTICS sub-nanosecond pulse high REPETITION rate
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