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Wideband spectrum sensing using step-sampling based on the multipath nyquist folding receiver

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Defence Technology（防务技术） 2024年第1期31卷 523-536页

作者： Kai-lun Tian Kai-li Jiang Sen Cao Jian Gao Ying Xiong Bin Tang Xu-ying Zhang Yan-fei Li University of Electronic Science and Technology of China Chengdu611731China China electronics Technology Group corporation 29th Research Institute Chengdu610036China

Wideband spectrum sensing with a high-speed analog-digital converter(ADC) presents a challenge for practical systems.The Nyquist folding receiver(NYFR) is a promising scheme for achieving cost-effective real-time spectrum sensing,which is subject to the complexity of processing the modulated outputs.In this case,a multipath NYFR architecture with a step-sampling rate for the different paths is proposed.The different numbers of digital channels for each path are designed based on the Chinese remainder theorem(CRT).Then,the detectable frequency range is divided into multiple frequency grids,and the Nyquist zone(NZ) of the input can be obtained by sensing these grids.Thus,high-precision parameter estimation is performed by utilizing the NYFR characteristics.Compared with the existing methods,the scheme proposed in this paper overcomes the challenge of NZ estimation,information damage,many computations,low accuracy,and high false alarm probability.Comparative simulation experiments verify the effectiveness of the proposed architecture in this paper.

关键词： Wideband spectrum sensing Sub-Nyquist sampling Step-sampling Nyquist folding receiver(NYFR) Multisignal processing

Availability evaluation of controller area networks under the influence of intermittent connection faults

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 555-568页

作者： Longkai WANG Leiming ZHANG Yong LEI State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China The 14th Research Institute of China electronics Technology Group corporation Nanjing 210039China

Controller area networks(CANs),as one of the widely used fieldbuses in the industry,have been extended to the automation field with strict standards for safety and reliability.In practice,factors such as fatigue and insulation wear of the cables can cause intermittent connection(IC)faults to occur frequently in the CAN,which will affect the dynamic behavior and the safety of the system.Hence,quantitatively evaluating the performance of the CAN under the influence of IC faults is crucial to real-time health monitoring of the system.In this paper,a novel methodology is proposed for real-time quantitative evaluation of CAN availability when considering IC faults,with the system availability parameter being calculated based on the network state transition model.First,the causal relationship between IC fault and network error response is constructed,based on which the IC fault arrival rate is estimated.Second,the states of the network considering IC faults are analyzed,and the deterministic and stochastic Petri net(DSPN)model is applied to describe the transition relationship of the states.Then,the parameters of the DSPN model are determined and the availability of the system is calculated based on the probability distribution and physical meaning of markings in the DSPN model.A testbed is constructed and case studies are conducted to verify the proposed methodology under various experimental setups.Experimental results show that the estimation results obtained using the proposed method agree well with the actual values.

关键词： Controller area network Intermittent connection fault Arrival rate Deterministic and stochastic Petri net Availability evaluation

A framework of force of information influence and application for C4KISR system

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Journal of Systems Engineering and electronics 2024年第2期35卷 430-443页

作者： MAO Shaojie DIAO Lianwang SUN Yu WANG Heng YI Kan XU Xin MAO Xiaobin ZHANG Kecheng SHENG Long Science and Technology on Information Systems Engineering Laboratory The 28th Research Institute of China Electronics Technology Group CorporationNanjing 210007China Unit 94860 of the PLA Nanjing 210008China

The subversive nature of information war lies not only in the information itself, but also in the circulation and application of information. It has always been a challenge to quantitatively analyze the function and effect of information flow through command, control, communications, computer, kill, intelligence,surveillance, reconnaissance (C4KISR) system. In this work, we propose a framework of force of information influence and the methods for calculating the force of information influence between C4KISR nodes of sensing, intelligence processing,decision making and fire attack. Specifically, the basic concept of force of information influence between nodes in C4KISR system is formally proposed and its mathematical definition is provided. Then, based on the information entropy theory, the model of force of information influence between C4KISR system nodes is constructed. Finally, the simulation experiments have been performed under an air defense and attack scenario. The experimental results show that, with the proposed force of information influence framework, we can effectively evaluate the contribution of information circulation through different C4KISR system nodes to the corresponding tasks. Our framework of force of information influence can also serve as an effective tool for the design and dynamic reconfiguration of C4KISR system architecture.

关键词： information warfare command control communications computer kill intelligence surveillance reconnaissance(C4KISR)system information circulation force of information influence information entropy

Fabrication,Microstructure and Mechanical Properties of in situ GNPs Reinforced Magnesium Matrix Composites

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 561-569页

作者： Peitang Zhao Xuejian Li Hailong Shi Xiaoshi Hu Chunlei Zhang Chao Xu Xiaojun Wang The 38th Research Institute of China electronics Technology Group corporation Hefei 230088China National Key Laboratory of Precision Hot Processing of Metal Harbin Institute of TechnologyHarbin 150001China

Graphene reinforced magnesium matrix composites have wide applications in automotive,electronics,aerospace and military fields due to the fascinating mechanical properties.However,it is difficult to realize the high strength and ductility simultaneously.In this work,the in situ liquid-state method was utilized to prepare GNPs/Mg6Zn composites via CO_(2)/Mg chemical reaction.Tensile strength of the GNPs/Mg6Zn composites was improved with increasing content of the GNPs.Meantime,the composites also exhibit a notable plastic deformation stage,and especially the ductility of 0.12 GNPs/Mg6Zn composites reaches 27.6%.Therefore,this novel preparation method has great potential application for fabricating Mg matrix composites with high strength and high ductility.

关键词： Magnesium matrix composite In situ composite Microstructure Mechanical properties

Data Component:An Innovative Framework for Information Value Metrics in the Digital Economy

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China Communications 2024年第5期21卷 17-35页

作者： Tao Xiaoming Wang Yu Peng Jieyang Zhao Yuelin Wang Yue Wang Youzheng Hu Chengsheng Lu Zhipeng Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Beijing 100084China China electronics corporation Beijing 100084China

The increasing dependence on data highlights the need for a detailed understanding of its behavior,encompassing the challenges involved in processing and evaluating it.However,current research lacks a comprehensive structure for measuring the worth of data elements,hindering effective navigation of the changing digital environment.This paper aims to fill this research gap by introducing the innovative concept of“data components.”It proposes a graphtheoretic representation model that presents a clear mathematical definition and demonstrates the superiority of data components over traditional processing methods.Additionally,the paper introduces an information measurement model that provides a way to calculate the information entropy of data components and establish their increased informational value.The paper also assesses the value of information,suggesting a pricing mechanism based on its significance.In conclusion,this paper establishes a robust framework for understanding and quantifying the value of implicit information in data,laying the groundwork for future research and practical applications.

关键词： data component data element data governance data science information theory

Lithium polysulfide solvation and speciation in the aprotic lithium-sulfur batteries

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Particuology 2024年第6期89卷 238-245页

作者： Jinhao Zhang Qingshan Fu Peng Li Ruibo Linghu Xiaozhong Fan Haibin Lin Juncao Bian Songbai Han Gengzhi Sun Long Kong Frontiers Science Center for Flexible electronics and Xi’an Institute of Flexible electronics Northwestern Polytechnical UniversityXi’an710129China China Automotive Innovation corporation Nanjing211100China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen518055China Institute of Advanced Materials Nanjing Tech UniversityNanjing211816China

Fingerprinting sulfur speciation in aprotic electrolytes is a key to understand fundamental chemistry and design well-performing lithium–sulfur(Li–S)batteries.Lithium polysulfide(LiPS)dissolution and deposition in ether-based electrolytes during redox reactions have been probed and established by spectroscopy and microscopy.However,detailed LiPS structure and solvation properties influenced by conventional and newly developed electrolytes remain elusive,which exert fundamental challenges and practical difficulties in decoupling battery performance from electrolyte volume.This perspective aims to provide timely information to uncover underlying mechanisms that rein in sulfur speciation by considering the charge density of LiPSs and the coordination strength of solvents/salts.The discussion starts with unlocking the baseline electrolyte formulation to investigate its role in LiPS formation and compatibility.After that,the term coordination strength is used instead of donor number and dielectric constant to describe interactions between solvents and LiPSs and to reveal LiPS structure evolution.This work is expected to encourage the discovery of new electrolyte working mechanisms to develop energy-dense and power-intensive Li–S batteries.

关键词： Sulfur speciation Redox kinetics Coordination strength Solvation chemistry Lithium-sulfur batteries

Rice Variety Classification Based on Optimized Near-Infrared Spectral Classification Model

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Rice science 2024年第1期31卷 6-9,I0009-I0012页

作者： YANG Sen WANG Zhenmin ZHANG Houqing SONG Wenlong College of Computer and Control Engineering Northeast Forestry UniversityHarbin 150040China The 49th Research Institute of China electronics Technology Group corporation Harbin 150000China

Accurate classification of rice variety is essential to ensure the brand value of high-quality rice products.Considering the impact of sample state on modeling optimization algorithms,rice samples after grinding and sealing were selected.To enhance the accuracy of rice variety classification,we introduced a spectral characteristic wavelength selection method based on adaptive sliding window permutation entropy(ASW-PE).

关键词： sealing Infrared grinding

Microwave photonic sideband selector based on thin-film lithium niobate platform

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Chinese Optics Letters 2024年第3期22卷 55-59页

作者：丁跃迪尚成林于文琦马向李少波曾成夏金松 54th Institute China Electronics Technology Group CorporationShijiazhuang 050011China Hebei Key Laboratory of Photonic Information Technology and Application(PITA) Shijiazhuang 050011China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China

We propose and demonstrate an integrated microwave photonic sideband selector based on the thin-film lithium niobate(TFLN)platform by integrating an electro-optic Mach-Zehnder modulator(MZM)and a thermo-optic tunable flat-top microring filter.The sideband selector has two functions:electro-optic modulation of wideband RF signal and sideband selection.The microwave photonic sideband selector supports processing RF signals up to 40 GHz,with undesired sidebands effectively suppressed by more than 25 d B.The demonstrated device shows great potential for TFLN integrated technology in microwave photonic applications,such as mixing and frequency measurement.

关键词： lithium niobate microwave photonics sideband selector

A Probabilistic Approach for Predicting Vessel Motion

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IEEE/CAA Journal of Automatica Sinica 2024年第8期 1877-1879页

作者： Qi Hu Jingyi Liu Zongyu Zuo the 7th Research Division Beihang University (BUAA) the 54th Research Institute of China electronics Technology Group corporation

Dear Editor,This letter addresses the challenge of forecasting the motion of real-world vessels over an extended period with a limited amount of available data. By employing stochastic differential equation (SDE)modeling, we integrate both deterministic and stochastic components of the available information. Subsequently, we establish a recursive prediction methodology based on Bayes’ rule to update the model state when new measurements are received. Furthermore, we develop a stochastic model tailored specifically to vessel dynamics and introduce an approximation method to tackle computational complexities.

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