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Localization in modified polar representation: hybrid measurements and closed-form solution

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Journal of Systems Engineering and electronics 2024年第3期35卷 575-588页

作者： CONG Xunchao SUN Yimao YANG Yanbing ZHANG Lei CHEN Liangyin The 10th research Institute of China electronics Technology group Corporation Chengdu 610036China College of Computer Science and Institute for industrial Internet research Sichuan UniversityChengdu 610065China

Classical localization methods use Cartesian or Polar coordinates, which require a priori range information to determine whether to estimate position or to only find bearings. The modified polar representation (MPR) unifies near-field and farfield models, alleviating the thresholding effect. Current localization methods in MPR based on the angle of arrival (AOA) and time difference of arrival (TDOA) measurements resort to semidefinite relaxation (SDR) and Gauss-Newton iteration, which are computationally complex and face the possible diverge problem. This paper formulates a pseudo linear equation between the measurements and the unknown MPR position,which leads to a closed-form solution for the hybrid TDOA-AOA localization problem, namely hybrid constrained optimization(HCO). HCO attains Cramér-Rao bound (CRB)-level accuracy for mild Gaussian noise. Compared with the existing closed-form solutions for the hybrid TDOA-AOA case, HCO provides comparable performance to the hybrid generalized trust region subproblem (HGTRS) solution and is better than the hybrid successive unconstrained minimization (HSUM) solution in large noise region. Its computational complexity is lower than that of HGTRS. Simulations validate the performance of HCO achieves the CRB that the maximum likelihood estimator (MLE) attains if the noise is small, but the MLE deviates from CRB earlier.

关键词： localization modified polar representation time difference of arrival(TDOA) angle of arrival(AOA) closed-form solution

Towards an integrated risk analysis security framework according to a systematic analysis of existing proposals

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Frontiers of Computer Science 2024年第3期18卷 199-216页

作者： Antonio SANTOS-OLMO Luis Enrique SÁNCHEZ David G.ROSADO Manuel A.SERRANO Carlos BLANCO Haralambos MOURATIDIS Eduardo FERNÁNDEZ-MEDINA GSyA research group University of Castilla-La ManchaCiudad Real 13071Spain Institute for Analytics and Data Science University of EssexColchester CO43SQUK Alarcos research group University of Castilla-La ManchaCiudad Real 13071Spain ISTR research group Department of Computer Science and ElectronicsUniversity of CantabriaSantander 39005Spain

The information society depends increasingly on risk assessment and management systems as means to adequately protect its key information *** availability of these systems is now vital for the protection and evolution of ***,several factors have led to an increasing need for more accurate risk analysis *** are:the speed at which technologies evolve,their global impact and the growing requirement for companies to *** analysis processes must consequently adapt to these new circumstances and new technological *** objective of this paper is,therefore,to present the results of an exhaustive analysis of the techniques and methods offered by the scientific community with the aim of identifying their main weaknesses and providing a new risk assessment and management *** analysis was carried out using the systematic review protocol and found that these proposals do not fully meet these new *** paper also presents a summary of MARISMA,the risk analysis and management framework designed by our research *** basis of our framework is the main existing risk standards and proposals,and it seeks to address the weaknesses found in these *** is in a process of continuous improvement,as is being applied by customers in several European and American *** consists of a risk data management module,a methodology for its systematic application and a tool that automates the process.

关键词： information security management security system security risk assessment and management

New industrialization: Characteristics, System Development and Implementation Pathway

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China Economist 2024年第1期19卷 2-13页

作者：无 research group of the Institute of industrial Economics Chinese Academy of Social Sciences(CASS)BeijingChina

New industrialization in China, different from its past economic development pattern or patterns in developed nations, is the country’s theoretical innovation based on the positive and negative experiences of industrialization at home and worldwide. New industrialization has various novel characteristics, including new sources of efficiency, new factors of production, new organizational forms, and new constraints. In addition, it has certain particularities arising from modernization with Chinese characteristics. This article summarizes the characteristics of new industrialization from the perspectives of people-centered approach, quality-first concept, independent innovation, green low-carbon economics, digital-real integration, and open circulation. There are four systems for promoting new industrialization: A self-sustained scientific and technological system, a high-end advanced manufacturing system, a green low-carbon circular system, and a division of labor system with domestic and international circulation. The Chinese new industrialization proposes the pathway and policy measures considering the new global situation and the requirements of new goals of strengthening organization and leadership, reducing factor cost, accelerating independent technological innovation, smoothing domestic and international circulation, and optimizing competition environment.

关键词： New industrialization Chinese modernization system building policy measures

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 *** 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 *** this case,a multipath NYFR architecture with a step-sampling rate for the different paths is *** 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 ***,high-precision parameter estimation is performed by utilizing the NYFR *** 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 *** 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

A Probabilistic Approach for Predicting Vessel Motion

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1877-1879页

作者： Qi Hu Jingyi Liu Zongyu Zuo 7th research Division Beihang University(BUAA)Beijing 100191China 54th research Institute of China electronics Technology group Corporation Shijiazhuang 050081China

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 *** employing stochastic differential equation(SDE)modeling,we integrate both deterministic and stochastic components of the available ***,we establish a recursive prediction methodology based on Bayes’rule to update the model state when new measurements are ***,we develop a stochastic model tailored specifically to vessel dynamics and introduce an approximation method to tackle computational ***,we present an application example and conduct a comparative experiment to validate the effectiveness and superiority of the proposed method.

关键词： method stochastic letter

Regression Method for Rail Fastener Tightness Based on Center-Line Projection Distance Feature and Neural Network

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 356-371页

作者： Yuanhang Wang Duxin Liu Sheng Guo Yifan Wu Jing Liu Wei Li Hongjie Wang Robotics research Center School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China China Construction industrial&Energy Engineering group Co. Ltd.Nanjing 210023China

In the railway system,fasteners have the functions of damping,maintaining the track distance,and adjusting the track ***,routine maintenance and inspection of fasteners are important to ensure the safe operation of track ***,assessment methods for fastener tightness include manual observation,acoustic wave detection,and image *** are limitations such as low accuracy and efficiency,easy interference and misjudgment,and a lack of accurate,stable,and fast detection *** at the small deformation characteristics and large elastic change of fasteners from full loosening to full tightening,this study proposes high-precision surface-structured light technology for fastener detection and fastener deformation feature extraction based on the center-line projection distance and a fastener tightness regression method based on neural ***,the method uses a 3D camera to obtain a fastener point cloud and then segments the elastic rod area based on the iterative closest point algorithm *** component analysis is used to calculate the normal vector of the segmented elastic rod surface and extract the point on the centerline of the elastic *** point is projected onto the upper surface of the bolt to calculate the projection ***,the mapping relationship between the projection distance sequence and fastener tightness is established,and the influence of each parameter on the fastener tightness prediction is ***,by setting up a fastener detection scene in the track experimental base,collecting data,and completing the algorithm verification,the results showed that the deviation between the fastener tightness regression value obtained after the algorithm processing and the actual measured value RMSE was 0.2196 mm,which significantly improved the effect compared with other tightness detection methods,and realized an effective fastener tightness regression.

关键词： Railway system Fasteners Tightness inspection Neural network regression 3D point cloud 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 *** 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 ***,quantitatively evaluating the performance of the CAN under the influence of IC faults is crucial to real-time health monitoring of the *** 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 ***,the causal relationship between IC fault and network error response is constructed,based on which the IC fault arrival rate is ***,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 ***,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 *** 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 ***,it is difficult to realize the high strength and ductility *** this work,the in situ liquid-state method was utilized to prepare GNPs/Mg6Zn composites via CO_(2)/Mg chemical *** strength of the GNPs/Mg6Zn composites was improved with increasing content of the ***,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