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Stability and performance analysis of the compressed Kalman filter algorithm for sparse stochastic systems

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Science China(Technological Sciences) 2024年第2期67卷 380-394页

作者： li RongJiang GAN Die xie SiYu LüJinHu Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Zhongguancun Laboratory Beijing 100049China School of Aeronautics and Astronautics University of Electronic Science and Technology of ChinaChengdu 611731China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

This paper considers the problem of estimating unknown sparse time-varying signals for stochastic dynamic *** deal with the challenges of extensive sparsity,we resort to the compressed sensing method and propose a compressed Kalman filter(KF)*** algorithm first compresses the original high-dimensional sparse regression vector via the sensing matrix and then obtains a KF estimate in the compressed low-dimensional ***,the original high-dimensional sparse signals can be well recovered by a reconstruction *** ensure stability and establish upper bounds on the estimation errors,we introduce a compressed excitation condition without imposing independence or stationarity on the system signal,and therefore suitable for feedback *** further present the performance of the compressed KF ***,we show that the mean square compressed tracking error matrix can be approximately calculated by a linear deterministic difference matrix equation,which can be readily evaluated,analyzed,and ***,a numerical example demonstrates that our algorithm outperforms the standard uncompressed KF algorithm and other compressed algorithms for estimating high-dimensional sparse signals.

关键词： sparse signal compressed sensing Kalman filter algorithm compressed excitation condition stochastic stability tracking performance

Multi-Stage Multidisciplinary Design Optimization Method for Enhancing Complete Artillery Internal Ballistic Firing Performance

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 793-819页

作者： Jipeng xie Guolai Yang liqun Wang Lei li School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China School of Intelligent Manufacturing Nanjing University of Science and Technology Zijin CollegeNanjing210023China

To enhance the comprehensive performance of artillery internal ballistics—encompassing power,accuracy,and service life—this study proposed a multi-stage multidisciplinary design optimization(MS-MDO)***,the comprehensive artillery internal ballistic dynamics(AIBD)model,based on propellant combustion,rotation band engraving,projectile axial motion,and rifling wear models,was established and *** model was systematically decomposed into subsystems from a system engineering *** study then detailed the MS-MDO methodology,which included Stage I(MDO stage)employing an improved collaborative optimization method for consistent design variables,and Stage II(Performance Optimization)focusing on the independent optimization of local design variables and performance *** methodology was applied to the AIBD *** demonstrated that the MS-MDO method in Stage I effectively reduced iteration and evaluation counts,thereby accelerating system-level ***,Stage II optimization markedly enhanced overall *** comprehensive evaluation results affirmed the effectiveness of the MS-MDO method.

关键词： Artillery internal ballistics dynamics multi-stage optimization multi-disciplinary design optimization collaborative optimization

Considering individual game behavior and time delay in the multi-channel rumor propagation model

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Communications in Theoretical Physics 2024年第7期76卷 11-31页

作者： Yafang Dong liang'an Huo Xiaoxiao xie Ming li Business School University of Shanghai for Science and Technology School of Intelligent Emergency Management University of Shanghai for Science and Technology

The rapid development of the Internet has accelerated the spread of rumors, posing challenges to social cohesion and stability. To address this, a multi-channel rumor propagation model incorporating individual game behavior and time delay is proposed. It depicts individuals strategically choosing propagation channels in the rumor spread process, capturing real-world intricacies more faithfully. Specifically, the model allowing spreaders to choose between text and video information base channels. Strategy adoption hinges on benefits versus costs, with payoffs dictating strategy and the propagation process determining an individual's state. By theoretical analysis of the model, the propagation threshold and equilibrium points are obtained. Then the stability of the model is further demonstrated based on Routh–Hurwitz judgment and Descartes' Rule of Signs. Numerical simulations are conducted to verify the correctness of the theoretical results and the sensitivity of the model to key parameters. The outcomes reveal that increasing the propagation cost of spreaders can significantly curb the spread of rumors. In contrast to the classical ISR model, rumors spread faster and more widely in the improved multi-channel rumor propagation model in this paper, which is a feature more aligned with real-world ***, the validity and predictive ability of the model are verified by using real rumor propagation data sets, indicating that the improved multi-channel rumor propagation model has good practical application and predictive value.

关键词： game behavior multi-channel rumor propagation time delay

Cobalt-Catalyzed Switchable[4+1]and[4+1+1]Spirocyclization of Aromatic Amides with 2-Diazo-1H-indene-1,3(2H)-dione:Access to Spiro Indene-2,1'-isoindolinones and Spiro Isochroman-3,1'-isoindolinones

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Chinese Journal of Chemistry 2024年第4期42卷 363-369页

作者： Bin li Mengmeng xie Jingyu li Nana Shen Xinying Zhang Xuesen Fan State Key Laboratory of Antiviral Drugs Pingyuan LaboratoryKey Laboratory of Green Chemical Media and ReactionsKey Laboratory for Yellow River and Huai River Water Environmental Pollution ControlMinistry of EducationSchool of EnvironmentSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiangHenan453007 China

Herein,we report a condition-controlled divergent synthesis of spiro indene-2,1'-isoindolinones and spiro isochroman-3,1'-isoindolinones through cobalt-catalyzed formal[4+1]and[4+1+1]spirocyclization of aromatic amides with 2-diazo-1H-indene-1,3(2H)-*** the reaction is carried out under air in ethyl acetate,spiro indene-2,1'-isoindolinones are formed through Co(II)-catalyzed C—H/N—H[4+1]*** the reaction is run under O2 in CH3CN,on the other hand,spiro isochroman-3,1'-isoindolinones are generated through Baeyer-Villiger oxidation of the in situ formed spiro indene-2,1'-isoindolinones with O2 as a cheaper and environmental-friendly oxygen *** general,these protocols have advantages such as using non-precious and earth-abundant metal catalyst,no extra additive,high efficiency and regioselectivity.A gram-scale synthesis and the removal of the directing group further highlight its utility.

关键词： Spiro indene-2,1'-isoindolinones Spiro isochroman-3,1'-isoindolinones 3d Transition metals Cobalt-catalyzed C-H Activation Switchable[4+1]and[4+1+1]spirocyclization Aromatic amides 2-Diazo-1H-indene-1,3(2H)-dione

High-Performance Recyclable Furan-based Epoxy Resin and Its Carbon Fiber Composites with Dense Hydrogen Bonding

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Chinese Journal of Polymer Science 2024年第1期42卷 73-86,I0008页

作者： Chang-Bo Zhao Lu-kun Feng Hui xie Ming-liang Wang Bing Guo Zhi-Yong Xue Cai-Zhen Zhu Jian Xu Advanced Materials Research Institute North China Electric Power UniversityBejing 102206China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China School of Science and Shenzhen Key Laboratory of Flexible Printed Electronics Technology and Shenzhen Key Laboratory of Advanced Functional Carbon Materials Research and Comprehensive ApplicationHarbin Institute of TechnologyShenzhen 518055China

The emerging biomass-based epoxy vitrimers hold great potential to fulfill the requirements for sustainable development of *** the existence of dynamic chemical bonds in vitrimers often reduces both the thermal and mechanical properties of epoxy resins, it is challenging to produce recyclable epoxy vitrimers with both excellent mechanical properties and good thermal stability. Herein, a monomer 4-(((5-(hydroxymethyl)furan-2-yl)methylene)amino)phenol(FCN) containing furan ring with potential to form high density of hydrogen bonding among repeating units is designed and copolymerized with glycerol triglycidyl ether to yield epoxy resin(FCN-GTE), which intrinsically has dual hydrogen bond networks, dynamic imine structure and resultant high performance. Importantly, as compared to the BPA-GTE, the FCN-GTE exhibits significantly improved mechanical properties owing to the increased density of hydrogen bond network and physical crosslinking interaction. Furthermore, density functional theory(DFT) calculation and in situ FTIR analysis is conducted to decipher the formation mechanism of hydrogen bond network. In addition, the FCN-GTE possesses superior UV shielding, chemical degradation, and recyclability because of the existence of abundant imine bonds. Notably, the FCN-GTE-based carbon fiber composites could be completely recycled in an amine *** study provides a facile strategy for synthesizing recyclable biomass-based high-performance epoxy vitrimers and carbon fiber composites.

关键词： Furan Hydrogen bond network Dynamic Schiff base Carbon fiber composites Recycling

Milling degree affects the fermentation properties of rice:perspectives from the composition of nutrients and gut microbiota via in vitro fermentation

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Food Science and Human Wellness 2024年第3期13卷 1578-1588页

作者： Yu Zhang Fan li Shutong Pan Bing Bai Kai Huang Sen li Hongwei Cao Tian xie Jian xie Xiao Guan School of Health Science and Engineering University of Shanghai for Science and TechnologyShanghai 200093China National Grain Industry(Urban Grain and Oil Security)Technology Innovation Center Shanghai 200093China Nutrition&Health Research Institute Co.Ltd. COFCO CorporationBeijing 102209China China Grain Wuhan Scientific Research&Design Institute Co.Ltd. Wuhan 430079China

Fermentation substrates of rice with different milling degrees(MDs) were prepared and fermented with human feces to compare their fermentation properties and effects on gut *** 0s,MD 5s and MD 60s represented brown rice,moderately-milled rice and white rice,*** in vitro fermentation,the MD 5s group showed higher starch utilization,compared with the MD 0s and 60s groups evaluated by Fourier transform infrared spectrometer,and confocal laser scanning *** of fermentation substrates of rice with different MDs on gut microbiota were evaluated by 16S rDNA *** the sample groups reduced the pH and produced short-chain fatty acids(SCFAs) and branched-chain fatty *** MD 5s group exhibited higher α-diversity than the MD 0s and 60s *** of Phascolarctobacterium,Blautia and norank_f_Ruminococcaceae were higher in the MD 0s and 5s groups,compared with the MD 60s *** bacteria were also positively correlated with the SCFAs production via Spearman correlation *** vitro culture assay revealed that fermentation substrates of MD 0s and 5s promoted the growth of two probiotics(Akkermansia muciniphila and Bifidobacterium adolescentis).Our results showed that moderate milling might be an appropriate way to produce rice products with richer nutrients and better fermentation properties.

关键词： Rice processing Milling Whole grains Gut microbiota

Origin of off-centering effect and the influence on heat transport in thermoelectrics

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Materials Futures 2024年第1期3卷 142-149页

作者： Hongyao xie li-Dong Zhao School of Materials Science and Engineering Beihang UniversityBeijing 100191People’s Republic of China

Recently,off-centering behavior has been discovered in a series of thermoelectric *** behavior indicates that the constituent atoms of the lattice displace from their coordination centers,leading to the locally distorted state and local symmetry breaking,while the material still retains its original crystallographic *** effect has been proved to be the root cause of ultralow thermal conductivity in off-centering materials,and is considered as an effective tool to regulate the thermal conductivity and improve the thermoelectric ***,we present a collection of recently discovered off-centering compounds,discuss their electronic origins and local coordination structures,and illuminate the underlying mechanism of the off-centering effect on phonon transport and thermal *** paper presents a comprehensive view of our current understanding to the off-centering effect,and provides a new idea for designing high performance thermoelectrics.

关键词： thermoelectric thermal conductivity off-centering behavior acoustic-optical phonon scattering

Fewer is more:efficient object detection in large aerial images

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Science China(Information Sciences) 2024年第1期67卷 105-123页

作者： Xingxing xie Gong CHENG Qingyang li Shicheng MIAO Ke li Junwei HAN School of Automation Northwestern Polytechnical University Zhengzhou Institute of Surveying and Mapping

Current mainstream object detection methods for large aerial images usually divide large images into patches and then exhaustively detect the objects of interest on all patches,no matter whether there exist objects or *** paradigm,although effective,is inefficient because the detectors have to go through all patches,severely hindering the inference *** paper presents an objectness activation network(OAN) to help detectors focus on fewer patches but achieve more efficient inference and more accurate results,enabling a simple and effective solution to object detection in large *** brief,OAN is a light fully-convolutional network for judging whether each patch contains objects or not,which can be easily integrated into many object detectors and jointly trained with them *** extensively evaluate our OAN with five advanced *** OAN,all five detectors acquire more than 30.0% speed-up on three large-scale aerial image datasets,meanwhile with consistent accuracy *** extremely large Gaofen-2 images(29200 × 27620 pixels),our OAN improves the detection speed by 70.5%.Moreover,we extend our OAN to driving-scene object detection and 4K video object detection,boosting the detection speed by 112.1% and 75.0%,respectively,without sacrificing the accuracy.

关键词： efficient object detection large aerial images objectness activation network

The Ω(2012) as a Hadronic Molecule

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Chinese Physics Letters 2024年第8期41卷 13-16页

作者： Ju-Jun xie li-Sheng Geng Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Sciences and Technology University of Chinese Academy of SciencesBeijing 101408China Southern Center for Nuclear-Science Theory(SCNT) Institute of Modern PhysicsChinese Academy of SciencesHuizhou 516000China School of Physics Beihang UniversityBeijing 102206China Beijing Key Laboratory of Advanced Nuclear Materials and Physics Beihang UniversityBeijing 102206China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

Recently,a new excited baryon state,Ω(2012),was observed in the invariant mass spectra of𝐾K^(-)■^(0) and K_(S)^(0)■^(-)by the Belle *** state has a narrow width(∼6 MeV)compared to other baryon states with a similar ***,we provide a mini-review on the Ω(2012)state from the molecular perspective,where it appears to be a dynamically generated state with spin-parity 3/2^(−)from the coupled-channels interactions of the K■(1530)and ηΩ in s-wave and K■ in𝑑***,alternative explanations for the Ω(2012)resonance are also discussed.

关键词： wave. invariant state