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Fusion of Dual-targeting Peptides with MAP30 Promotes the Apoptosis of MDA-MB-231 Breast Cancer Cells
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作者 YANG Yi-Xuan WANG Xin-Yi +5 位作者 CHEN Wei-Wei GAN Li SUN Yu LIN Tong ZHAO Wei-Chun ZHU Zhen-Hong 《中国生物化学与分子生物学报》 北大核心 2025年第2期260-272,共13页
Momordica antiviral protein 30 kD(MAP30)is a type I ribosome-inactivating protein(RIP)with antibacterial,anti-HIV and antitumor activities but lacks the ability to target tumor cells.To increase its tumor-targeting ab... Momordica antiviral protein 30 kD(MAP30)is a type I ribosome-inactivating protein(RIP)with antibacterial,anti-HIV and antitumor activities but lacks the ability to target tumor cells.To increase its tumor-targeting ability,the arginine-glycine-aspartic(RGD)peptide and the epidermal growth factor receptor interference(EGFRi)peptide were fused with MAP30,which was named ELRL-MAP30.The efficiency of targeted therapy for triple-negative breast cancer(TNBC)MDA-MB-231 cells,which lack the expression of estrogen receptor(ER),Progesterone receptor(PgR)and human epidermal growth factor receptor-2(HER2),is limited.In this study,we focus on exploring the effect and mechanism of ELRL-MAP30 on TNBC MDA-MB-231 cells.First,we discovered that ELRL-MAP30 significantly inhibited the migration and invasion of MDA-MB-231 cells and induced MDA-MB-231 cell apoptosis.Moreover,ELRL-MAP30 treatment resulted in a significant increase in Bax expression and a decrease in Bcl-2 expression.Furthermore,ELRL-MAP30 triggered apoptosis via the Fak/EGFR/Erk and Ilk/Akt signaling pathways.In addition,recombinant ELRL-MAP30 can inhibit chicken embryonic angiogenesis,and also inhibit the tube formation ability of human umbilical vein endothelial cells(HUVECs),indicating its potential therapeutic effects on tumor angiogenesis.Collectively,these results indicate that ELRL-MAP30 has significant tumor-targeting properties in MDA-MB-231 cancer cells and reveals potential therapeutic effects on angiogenesis.These findings indicate the potential role of ELRL-MAP30 in the targeted treatment of the TNBC cell line MDA-MB-231. 展开更多
关键词 arginine-glycine-aspartic peptide(RGD) epidermal growth factor receptor interference peptide(EGFRi) momordica antiviral protein(MAP30) MDA-MB-231 cell tumor targeting APOPTOSIS
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Realizing high-speed target tracking by using multi-rate feedforward predictive control for the acquisition, tracking, and pointing system
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作者 Hang Li Gaoliang Peng +4 位作者 Xiaobiao Shan Mingyuan Zhao Wei Zhang Jinghan Wang Feng Cheng 《Defence Technology(防务技术)》 2025年第7期137-151,共15页
The acquisition,tracking,and pointing(ATP)system is widely used in target tracking,counter-UAV operations,and other related fields.As UAV technology develops,there is a growing demand to enhance the tracking capabilit... The acquisition,tracking,and pointing(ATP)system is widely used in target tracking,counter-UAV operations,and other related fields.As UAV technology develops,there is a growing demand to enhance the tracking capabilities of ATP systems.However,in practical applications,ATP systems face various design constraints and functional limitations,making it infeasible to indefinitely improve hardware performance to meet tracking requirements.As a result,tracking algorithms are required to execute increasingly complex tasks.This study introduces a multi-rate feedforward predictive controller to address issues such as low image feedback frequency and significant delays in ATP systems,which lead to tracking jitter,poor tracking performance,low precision,and target loss.At the same time,the pro-posed approach aims to improve the tracking capabilities of ATP systems for high-speed and highly maneuverable targets under conditions of low sampling feedback rates and high feedback delays.The method suggested is also characterized by its low order,fast response,and robustness to model parameter variations.In this study,an actual ATP system is built for target tracking test,and the proposed algorithm is fully validated in terms of simulation and actual system application verification.Results from both simulations and experiments demonstrate that the method effectively compensates for delays and low sampling rates.For targets with relative angular velocities ranging from 0 to 90°/s and angular accelerations between 0 and 470°/s^(2),the system improved tracking accuracy by 70.0%-89.9%at a sampling frequency of 50 Hz and a delay of 30 m s.Moreover,the compensation algorithm demonstrated consistent performance across actuators with varying characteristics,further confirming its robustness to model insensitivity.In summary,the proposed algorithm considerably enhances the tracking accuracy and capability of ATP systems for high-speed and highly maneuverable targets,reducing the probability of target loss from high speed.This approach offers a practical solution for future multi-target tracking across diverse operational scenarios. 展开更多
关键词 Multi-rate systems Predictive feedforward control Target tracking Laser weapon
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Design and simulation of the ATP system considering the advanced targeting angle in quantum positioning system 被引量:2
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作者 CONG Shuang ZHANG Xiang DUAN Shiqi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第5期1227-1236,共10页
A compensation implementation scheme of the advanced targeting process based on the fine tracking system is proposed in this paper.Based on the working process of the quantum positioning system(QPS)and its acquisition... A compensation implementation scheme of the advanced targeting process based on the fine tracking system is proposed in this paper.Based on the working process of the quantum positioning system(QPS)and its acquisition,tracking and pointing(ATP)system,the advanced targeting subsystem of the ATP system is designed.Based on six orbital parameters of the quantum satellite Mozi,the advanced targeting azimuth angle and pitch angle are transformed into the dynamic tracking center of the fine tracking system in the ATP system.The deviation of the advanced targeting process is analyzed.In the Simulink,the simulation experiment of the ATP system considering the deviation compensation of the advanced targeting is carried out,and the results are analyzed. 展开更多
关键词 quantum positioning system(QPS) ACQUISITION tracking and pointing(ATP) advanced targeting
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Battlefield target intelligence system architecture modeling and system optimization
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作者 LI Wei WANG Yue +2 位作者 JIA Lijuan PENG Senran HE Ruixi 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1190-1210,共21页
To address the current problems of poor generality,low real-time,and imperfect information transmission of the battlefield target intelligence system,this paper studies the battlefield target intelligence system from ... To address the current problems of poor generality,low real-time,and imperfect information transmission of the battlefield target intelligence system,this paper studies the battlefield target intelligence system from the top-level perspective of multi-service joint warfare.First,an overall planning and analysis method of architecture modeling is proposed with the idea of a bionic analogy for battlefield target intelligence system architecture modeling,which reduces the difficulty of the planning and design process.The method introduces the Department of Defense architecture framework(DoDAF)modeling method,the multi-living agent(MLA)theory modeling method,and other combinations for planning and modeling.A set of rapid planning methods that can be applied to model the architecture of various types of complex systems is formed.Further,the liveness analysis of the battlefield target intelligence system is carried out,and the problems of the existing system are presented from several aspects.And the technical prediction of the development and construction is given,which provides directional ideas for the subsequent research and development of the battlefield target intelligence system.In the end,the proposed architecture model of the battlefield target intelligence system is simulated and verified by applying the colored Petri nets(CPN)simulation software.The analysis demonstrates the reasonable integrity of its logic. 展开更多
关键词 battlefield target intelligence system architecture modeling bionic design system optimization simulation verification
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Dense Small Target Image Detection Algorithm Based on the Improved YOLOv8
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作者 MA Jing-yu SI Zhan-jun 《印刷与数字媒体技术研究》 北大核心 2025年第2期65-71,97,共8页
The YOLOv8 model faces challenges with dense target distribution and small size,resulting in lower accuracy in dense small target detection.To address these issues,an improved small target detection algorithm based on... The YOLOv8 model faces challenges with dense target distribution and small size,resulting in lower accuracy in dense small target detection.To address these issues,an improved small target detection algorithm based on the YOLOv8 model was proposed in this paper.Firstly,the Global Attention Module(GAM)was introduced to enhance data prediction capability and model expression ability.Secondly,the Space-to-Depth(SPD)module was incorporated into the backbone network for fine-grained feature information learning to mitigate feature information loss due to down-sampling.Finally,a 160 pixels×160 pixels feature layer was added to expand small target feature information and effectively reduce instances of missed targets.Experimental validation on the public VisDrone2019 UAV small target detaset demonstrated that the proposed model achieves significant performance improvement in small target detection tasks compared to existing models,exhibiting higher accuracy. 展开更多
关键词 YOLOv8 Small targets GAM SPD
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THBS4 in Disease:Mechanisms,Biomarkers,and Therapeutic Opportunities
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作者 HUANG De-Ying LI Yan-Hong +1 位作者 BAI Xiu-Feng LIU Yi 《生物化学与生物物理进展》 北大核心 2025年第9期2217-2232,共16页
Thrombospondin 4(THBS4;TSP4),a crucial component of the extracellular matrix(ECM),serves as an important regulator of tissue homeostasis and various pathophysiological processes.As a member of the evolutionarily conse... Thrombospondin 4(THBS4;TSP4),a crucial component of the extracellular matrix(ECM),serves as an important regulator of tissue homeostasis and various pathophysiological processes.As a member of the evolutionarily conserved thrombospondin family,THBS4 is a multidomain adhesive glycoprotein characterized by six distinct structural domains that mediate its diverse biological functions.Through dynamic interactions with various ECM components,THBS4 plays pivotal roles in cell adhesion,proliferation,inflammation regulation,and tissue remodeling,establishing it as a key modulator of microenvironmental organization.The transcription and translation of THBS4 gene,as well as the activity of the THBS4 protein,are tightly regulated by multiple signaling pathways and extracellular cues.Positive regulators of THBS4 include transforming growth factorβ(TGF-β),interferonγ(IFNγ),granulocyte-macrophage colony-stimulating factor(GM-CSF),bone morphogenetic proteins(BMP12/13),and other regulatory factors(such as B4GALNT1,ITGA2/ITGB1,PDGFRβ,etc.),which upregulate THBS4 at the mRNA and/or protein level.Conversely,oxidized low-density lipoprotein(OXLDL)acts as a potent negative regulator of THBS4.This intricate regulatory network ensures precise spatial and temporal control of THBS4 expression in response to diverse physiological and pathological stimuli.Functionally,THBS4 acts as a critical signaling hub,influencing multiple downstream pathways essential for cellular behavior and tissue homeostasis.The best-characterized pathways include:(1)the PI3K/AKT/mTOR axis,which THBS4 modulates through both direct and indirect interactions with integrins and growth factor receptors;(2)Wnt/β-catenin signaling,where THBS4 functions as either an activator or inhibitor depending on the cellular context;(3)the suppression of DBET/TRIM69,contributing to its diverse regulatory roles.These signaling connections position THBS4 as a master regulator of cellular responses to microenvironmental changes.Substantial evidence links aberrant THBS4 expression to a range of pathological conditions,including neoplastic diseases,cardiovascular disorders,fibrotic conditions,neurodegenerative diseases,musculoskeletal disorders,and atopic dermatitis.In cancer biology,THBS4 exhibits context-dependent roles,functioning either as a tumor suppressor or promoter depending on the tumor type and microenvironment.In the cardiovascular system,THBS4 contributes to both adaptive remodeling and maladaptive fibrotic responses.Its involvement in fibrotic diseases arises from its ability to regulate ECM deposition and turnover.The diagnostic and therapeutic potential of THBS4 is particularly promising in oncology and cardiovascular medicine.As a biomarker,THBS4 expression patterns correlate significantly with disease progression and patient outcomes.Therapeutically,targeting THBS4-mediated pathways offers novel opportunities for precision medicine approaches,including anti-fibrotic therapies,modulation of the tumor microenvironment,and enhancement of tissue repair.This comprehensive review systematically explores three key aspects of THBS4 research:(1)the fundamental biological functions of THBS4 in ECM organization;(2)its mechanistic involvement in various disease pathologies;(3)its emerging potential as both a diagnostic biomarker and therapeutic target.By integrating recent insights from molecular studies,animal models,and clinical investigations,this review provides a framework for understanding the multifaceted roles of THBS4 in health and disease.The synthesis of current knowledge highlights critical research gaps and future directions for exploring THBS4-targeted interventions across multiple disease contexts.Given its unique position at the intersection of ECM biology and cellular signaling,THBS4 represents a promising frontier for the development of novel diagnostic tools and therapeutic strategies in precision medicine. 展开更多
关键词 thrombospondin 4 CANCERS cardiovascular diseases fibrotic diseases targeted pharmacological
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Research on SAR Image Lightweight Detection Based on Improved YOLOV8
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作者 WANG Qing SI Zhan-jun 《印刷与数字媒体技术研究》 北大核心 2025年第1期93-100,共8页
In recent years,with the development of synthetic aperture radar(SAR)technology and the widespread application of deep learning,lightweight detection of SAR images has emerged as a research direction.The ultimate goal... In recent years,with the development of synthetic aperture radar(SAR)technology and the widespread application of deep learning,lightweight detection of SAR images has emerged as a research direction.The ultimate goal is to reduce computational and storage requirements while ensuring detection accuracy and reliability,making it an ideal choice for achieving rapid response and efficient processing.In this regard,a lightweight SAR ship target detection algorithm based on YOLOv8 was proposed in this study.Firstly,the C2f-Sc module was designed by fusing the C2f in the backbone network with the ScConv to reduce spatial redundancy and channel redundancy between features in convolutional neural networks.At the same time,the Ghost module was introduced into the neck network to effectively reduce model parameters and computational complexity.A relatively lightweight EMA attention mechanism was added to the neck network to promote the effective fusion of features at different levels.Experimental results showed that the Parameters and GFLOPs of the improved model are reduced by 8.5%and 7.0%when mAP@0.5 and mAP@0.5:0.95 are increased by 0.7%and 1.8%,respectively.It makes the model lightweight and improves the detection accuracy,which has certain application value. 展开更多
关键词 YOLOv8 Synthetic aperture radar image LIGHTWEIGHT Target detection
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Infrared small target detection algorithm via partial sum of the tensor nuclear norm and direction residual weighting
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作者 SUN Bin XIA Xing-Ling +1 位作者 FU Rong-Guo SHI Liang 《红外与毫米波学报》 北大核心 2025年第2期277-288,共12页
Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small targe... Aiming at the problem that infrared small target detection faces low contrast between the background and the target and insufficient noise suppression ability under the complex cloud background,an infrared small target detection method based on the tensor nuclear norm and direction residual weighting was proposed.Based on converting the infrared image into an infrared patch tensor model,from the perspective of the low-rank nature of the background tensor,and taking advantage of the difference in contrast between the background and the target in different directions,we designed a double-neighborhood local contrast based on direction residual weighting method(DNLCDRW)combined with the partial sum of tensor nuclear norm(PSTNN)to achieve effective background suppression and recovery of infrared small targets.Experiments show that the algorithm is effective in suppressing the background and improving the detection ability of the target. 展开更多
关键词 infrared small target detection infrared patch tensor model partial sum of the tensor nuclear norm direction residual weighting
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A novel detection method for warhead fragment targets in optical images under dynamic strong interference environments
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作者 Guoyi Zhang Hongxiang Zhang +4 位作者 Zhihua Shen Deren Kong Chenhao Ning Fei Shang Xiaohu Zhang 《Defence Technology(防务技术)》 2025年第1期252-270,共19页
A measurement system for the scattering characteristics of warhead fragments based on high-speed imaging systems offers advantages such as simple deployment,flexible maneuverability,and high spatiotemporal resolution,... A measurement system for the scattering characteristics of warhead fragments based on high-speed imaging systems offers advantages such as simple deployment,flexible maneuverability,and high spatiotemporal resolution,enabling the acquisition of full-process data of the fragment scattering process.However,mismatches between camera frame rates and target velocities can lead to long motion blur tails of high-speed fragment targets,resulting in low signal-to-noise ratios and rendering conventional detection algorithms ineffective in dynamic strong interference testing environments.In this study,we propose a detection framework centered on dynamic strong interference disturbance signal separation and suppression.We introduce a mixture Gaussian model constrained under a joint spatialtemporal-transform domain Dirichlet process,combined with total variation regularization to achieve disturbance signal suppression.Experimental results demonstrate that the proposed disturbance suppression method can be integrated with certain conventional motion target detection tasks,enabling adaptation to real-world data to a certain extent.Moreover,we provide a specific implementation of this process,which achieves a detection rate close to 100%with an approximate 0%false alarm rate in multiple sets of real target field test data.This research effectively advances the development of the field of damage parameter testing. 展开更多
关键词 Damage parameter testing Warhead fragment target detection High-speed imaging systems Dynamic strong interference disturbance suppression Variational bayesian inference Motion target detection Faint streak-like target detection
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Deformation patterns of steel targets against long rod penetration
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作者 Chengxin Du Peng Wang +4 位作者 Bingnan Xing Feng Zhou Wenzheng Lv Zhonghua Du Guangfa Gao 《Defence Technology(防务技术)》 2025年第8期272-287,共16页
An experimental and finite element simulation investigation are conducted to study the deformation patterns of steel targets during the penetration process of tungsten alloy long rods,as well as the influence of stren... An experimental and finite element simulation investigation are conducted to study the deformation patterns of steel targets during the penetration process of tungsten alloy long rods,as well as the influence of strength of the target on the deformation patterns.The experimental results revealed slight mass loss in the first layer of the steel target during the transient entrance phase,with an extremely negligible loss in target mass during the quasi-steady penetration phase.The results of macro-analysis,micro-analysis and simulation show that the eroded target material migrated towards the periphery of the crater,causing an increase in the target's thickness,remained within the target,instead of flowing out of the crater.Therefore,the process of long rods penetrating the metal target is considered as a process of backward extrusion.By combining the backward extrusion theory with energy conservation,a penetration depth model for long rods penetrating a metal target,taking into account both the diameter of the crater and the friction coefficient between the rod and the target,has been established.Although the model is not yet perfect,it innovatively applies the principles of solid mechanics to the study of long rod penetration.Additionally,it takes into account the friction coefficient between the rod and the target during the penetration process.Therefore,this model provides a new research direction for future studies on long rod penetration. 展开更多
关键词 Long-rod penetration Mass loss of target Deformation patterns of targets Penetration depth model Backward extrusion theory
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Localization and tracking of multiple quadrotors with collision avoidance:Theory and experiment
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作者 Guang Yang Juntong Qi +4 位作者 Mingming Wang Yan Peng Chong Wu Yuan Ping Hailong Huang 《Defence Technology(防务技术)》 2025年第8期338-350,共13页
Multiple quadrotors target encirclement is widely used in the intelligent field,as it can effectively monitor and control target behavior.However,it faces the danger of collision,as well as difficulties in localizatio... Multiple quadrotors target encirclement is widely used in the intelligent field,as it can effectively monitor and control target behavior.However,it faces the danger of collision,as well as difficulties in localization and tracking.Therefore,we propose a complete target encirclement method.Firstly,based on Hooke's law,a collision avoidance controller is designed to maintain a safe flying distance among quadrotors.Then,based on the consensus theory,a formation tracking controller is designed to meet the requirements of formation transformation and encirclement tasks,and a stability proof based on Lyapunov was provided.Besides,the target detection is designed based on YOLOv5s,and the target location model is constructed based on the principle of pinhole projection and triangle similarity.Finally,we conducted experiments on the built platform,with 3 reconnaissance quadrotors detecting and localization 3 target vehicles and 7 hunter quadrotors tracking them.The results show that the minimum average error for localization targets with reconnaissance quadrotors can reach 0.1354 m,while the minimum average error for tracking with hunter quadrotors is only 0.2960 m.No quadrotors collision occurred in the whole formation transformation and tracking experiment.In addition,compared with the advanced methods,the proposed method has better performance. 展开更多
关键词 Multiple quadrotors Collision avoidance Target localization TRACKING Outdoor experiments
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A processing technique for accurate target angle estimation using wideband monopulse radars
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作者 CHEN Chengzeng LIU Dan +1 位作者 XU Xiaojian LU Yaobing 《Journal of Systems Engineering and Electronics》 2025年第2期370-379,共10页
Accurate target angle estimation is one of the chal-lenges for wideband radars due to the fact that target occupies multiple range bins,resulting in lower energy or signal to noise ratio in a single range bin.This pap... Accurate target angle estimation is one of the chal-lenges for wideband radars due to the fact that target occupies multiple range bins,resulting in lower energy or signal to noise ratio in a single range bin.This paper proposes a processing technique for enhanced accuracy of target angle estimates for wideband monopulse radars.Firstly,to accumulate the energy of the received echo signals from different scatterers on a target,the phase difference between different scatterers on a target is estimated using the minimum entropy phase estimation method combining with the correlation between adjacent pulses.Then,the monopulse ratio is obtained by using the signals from the accumulated sum and difference channels.The target angle is estimated by weighting the accumulated echo energy for accu-racy enhancement.Experimental results based on both numeri-cal simulation and measured data are presented to validate the effectiveness of the proposed technique. 展开更多
关键词 wideband radar target angle estimation adjacent pulses correlation.
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Situation maintenance-based cooperative guidance strategy for intercepting a superior target
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作者 Xinghui Yan Yuzhong Tang +2 位作者 Heng Shi Yulei Xu Yiding Liu 《Defence Technology(防务技术)》 2025年第6期250-267,共18页
A situation maintenance-based cooperative guidance strategy is proposed to intercept a high-speed and high-maneuverability target via inferior missiles.Reachability and relative motion analyses are conducted to develo... A situation maintenance-based cooperative guidance strategy is proposed to intercept a high-speed and high-maneuverability target via inferior missiles.Reachability and relative motion analyses are conducted to develop and pursue virtual targets,respectively.A two-stage guidance strategy under nonlinear kinematics is developed on the basis of virtual targets.The first stage optimizes the coverage and collision situation by pursuing virtual targets under specific angular constraints.The second stage subsequently intercepts the superior target based on the handover condition optimized by the first stage.Numerical simulation results are provided to compare the effectiveness and superiority of the proposed strategy with those of the reachability-based cooperative strategy(RCS),coverage-based cooperative guidance(CBCG)and augmented proportional navigation(APN)under various maneuvering modes. 展开更多
关键词 Cooperative interception Situation maintenance Reachability analysis Virtual target
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Distributed event-triggered control for UAV swarm target fencing with network connectivity preservation and collision avoidance
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作者 Xiuxia Yang Hao Yu +1 位作者 Yi Zhang Wenqiang Yao 《Defence Technology(防务技术)》 2025年第8期412-427,共16页
This paper proposes a distributed event-triggered control(ETC)framework to address cooperative target fencing challenges in UAV swarm.The proposed architecture eliminates the reliance on preset formation parameters wh... This paper proposes a distributed event-triggered control(ETC)framework to address cooperative target fencing challenges in UAV swarm.The proposed architecture eliminates the reliance on preset formation parameters while achieving multi-objective cooperative control for target fencing,network connectivity preservation,collision avoidance,and communication efficiency optimization.Firstly,a differential state observer is constructed to obtain the target's unmeasurable states.Secondly,leveraging swarm selforganization principles,a geometric-constraint-free distributed fencing controller is designed by integrating potential field methods with consensus theory.The controller dynamically adjusts inter-UAV distances via single potential function,enabling coordinated optimization of persistent network connectivity and collision-free motion during target fencing.Thirdly,a dual-threshold ETC mechanism based on velocity consensus deviation and fencing error is proposed,which can be triggered based on task features to dynamically adjust the communication frequency,significantly reduce the communication burden and exclude Zeno behavior.Theoretical analysis demonstrates the stability of closed-loop systems.Multi-scenario simulations show that the proposed method can achieve robust fencing under target maneuverability,partial UAV failures,and communication disturbances. 展开更多
关键词 Dual-threshold ETC mechanism UAV swarm Cooperative control Distributed control Target fencing Differential state observer
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Impact time control guidance for moving-target considering velocity variation and field-of-view constraint
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作者 YANG Hao ZHANG Shifeng +1 位作者 BAI Xibin YANG Chengye 《Journal of Systems Engineering and Electronics》 2025年第2期552-568,共17页
In the existing impact time control guidance (ITCG) laws for moving-targets, the effects of time-varying velocity caused by aerodynamics and gravity cannot be effectively con-sidered. Therefore, an ITCG with field-of-... In the existing impact time control guidance (ITCG) laws for moving-targets, the effects of time-varying velocity caused by aerodynamics and gravity cannot be effectively con-sidered. Therefore, an ITCG with field-of-view (FOV) constraints based on biased proportional navigation guidance (PNG) is developed in this paper. The remaining flight time (time-to-go) estimation method is derived considering aerodynamic force and gravity. The number of differential equations is reduced and the integration step is increased by changing the integral variable, which makes it possible to obtain time-to-go through integration. An impact time controller with FOV constraints is proposed by analyzing the influence of the biased term on time-to-go and FOV constraint. Then, numerical simulations are performed to verify the correctness and superiority of the method. 展开更多
关键词 moving target time-varying velocity time-to-go esti-mation field-of-view(FOV)constraint flight time control.
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Joint planning method for cross-domain unmanned swarm target assignment and mission trajectory
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作者 WANG Ning LIANG Xiaolong +2 位作者 LI Zhe HOU Yueqi YANG Aiwu 《Journal of Systems Engineering and Electronics》 2025年第3期736-753,共18页
Compared with single-domain unmanned swarms,cross-domain unmanned swarms continue to face new challenges in terms of platform performance and constraints.In this paper,a joint unmanned swarm target assignment and miss... Compared with single-domain unmanned swarms,cross-domain unmanned swarms continue to face new challenges in terms of platform performance and constraints.In this paper,a joint unmanned swarm target assignment and mission trajectory planning method is proposed to meet the requirements of cross-domain unmanned swarm mission planning.Firstly,the different performances of cross-domain heterogeneous platforms and mission requirements of targets are characterised by using a collection of operational resources.Secondly,an algorithmic framework for joint target assignment and mission trajectory planning is proposed,in which the initial planning of the trajectory is performed in the target assignment phase,while the trajectory is further optimised afterwards.Next,the estimation of the distribution algorithms is combined with the genetic algorithm to solve the objective function.Finally,the algorithm is numerically simulated by specific cases.Simulation results indicate that the proposed algorithm can perform effective task assignment and trajectory planning for cross-domain unmanned swarms.Furthermore,the solution performance of the hybrid estimation of distribution algorithm(EDA)-genetic algorithm(GA)algorithm is better than that of GA and EDA. 展开更多
关键词 cross-domain swarm unmanned system target assignment trajectory planning joint planning hybrid estimation of distribution algorithm(EDA)-genetic algorithm(GA)
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Waveform diversity based sonar system for target localization 被引量:6
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作者 Lijie Zhang dianguo Huang +3 位作者 Yong Jin Yunshan Hou Min Jiang Qunfei Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期186-190,共5页
A new monostatic array system taking advantage of diverse waveforms to improve the performance of underwater tar- get localization is proposed. Unlike the coherent signals between different elements in common active a... A new monostatic array system taking advantage of diverse waveforms to improve the performance of underwater tar- get localization is proposed. Unlike the coherent signals between different elements in common active array, the transmitted signals from different elements here are spatially orthogonal waveforms which allow for array processing in the transit mode and result in an extension of array aperture. The mathematical derivation of Capon estimator for this sonar system is described in detail. And the performance of this orthogonal-waveform based sonar is an- alyzed and compared with that of its phased-array counterpart by water tank experiments. Experimental results show that this sonar system could achieve 12 dB-15 dB additional array gain over its phased-array counterpart, which means a doubling of maximum detection range. Moreover, the angular resolution is significantly improved at lower SNR. 展开更多
关键词 SONAR orthogonal signal transmission CAPON target localization.
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Tracking method based on separation and combination of the measurements for radar and IR fusion system 被引量:6
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作者 Wang Qingchao Wang Wenfei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期241-246,共6页
A new distributed fusion method of radar/infrared (IR) tracking system based on separation and combination of the measurements is proposed by analyzing the influence of rate measurement. The rate information separat... A new distributed fusion method of radar/infrared (IR) tracking system based on separation and combination of the measurements is proposed by analyzing the influence of rate measurement. The rate information separated from the radar measurements together with measurements of IR form a pseudo vector of IR, and the corresponding filter is designed. The results indicate that the method not only makes a great improvement to the local tracker's performance, but also improves the global tracking precision efficiently. 展开更多
关键词 information fusion target tracking range rate measurement extended Kalman filter
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Calibration method of phase distortions for cross polarization channel of instantaneous polarization radar system 被引量:7
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作者 Huanyao Dai Yuliang Chang Dahai Dai Yongzhen Li XuesongWang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期211-218,共8页
A novel polarimetric calibration method for new target property measurement radar system is presented. Its applica- tion in the real radar system is also discussed. The analysis indicates that instantaneous polarizati... A novel polarimetric calibration method for new target property measurement radar system is presented. Its applica- tion in the real radar system is also discussed. The analysis indicates that instantaneous polarization radar ([PR) has inherent cross-polarization measurement error. The proposed method can effectively eliminate this error, and thus enhance the polarization scattering matrix (PSM) measurement precision. The phase error caused by digital receiver's direct IF sampling and mixing of two orthogonal polarization channels can be removed. Consequently, the inherent error of target polarization scattering measurement of the instantaneous polarization radar system is well revised. It has good reference value for further ploarimetric calibration and high practical application prospect. 展开更多
关键词 instantaneous polarization radar target scattering ma- trix (PSM) polarization measurement polarimetric calibration.
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An Improved Double r-iteration IOD Method for GEO UCTs Based on SBSS System 被引量:2
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作者 TANG Yi ZHONG Wenan +1 位作者 LI Shuang SHOU Junming 《空间科学学报》 CAS CSCD 北大核心 2014年第6期867-871,共5页
The purpose of initial orbit determination,especially in the case of angles-only data for observation,is to obtain an initial estimate that is close enough to the true orbit to enable subsequent precision orbit determ... The purpose of initial orbit determination,especially in the case of angles-only data for observation,is to obtain an initial estimate that is close enough to the true orbit to enable subsequent precision orbit determination processing to be successful.However,the classical angles-only initial orbit determination methods cannot deal with the observation data whose Earth-central angle is larger than 360°.In this paper,an improved double r-iteration initial orbit determination method to deal with the above case is presented to monitor geosynchronous Earth orbit objects for a spacebased surveillance system.Simulation results indicate that the improved double r-iteration method is feasible,and the accuracy of the obtained initial orbit meets the requirements of re-acquiring the object. 展开更多
关键词 DOUBLE r-iteration Initial ORBITAL determination Geosynchronous object Uncorrelated TARGETS SPACE-BASED space surveillance
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