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Covariate-Assisted Matrix Completion with Multiple Structural Breaks

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Journal of Systems Science & Complexity 2024年第2期37卷 692-728页

作者： MENG Jing feng Long ZOU Changliang WANG Zhaojun School of Statistics and Data Science KLMDASRLEBPSand LPMCNankai UniversityTianjin 300071China

In matrix completion,additional covariates often provide valuable information for completing the unobserved entries of a high-dimensional low-rank matrix *** this paper,the authors consider the matrix recovery problem when there are multiple structural breaks in the coefficient matrix β under the column-space-decomposition model A=Xβ+B.A cumulative sum(CUSUM)statistic is constructed based on the penalized estimation of β.Then the CUSUM is incorporated into the Wild Binary Segmentation(WBS)algorithm to consistently estimate the location of ***,a nearly-optimal recovery of A is *** findings are further corroborated via numerical experiments and a real-data application.

关键词： Additional covariates matrix completion multiple structural breaks wild Binary Segmentation

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Cotton leaf disease detection method based on improved SSD

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 211-220页

作者： Wenjuan Guo Shuo feng Quan feng Xiangzhou Li Xueze Gao College of Mechanical and Electrical Engineering Gansu Agricultural UniversityLanzhou 730070China School of Cyber Security Gansu University of Political Science and LawLanzhou 730070China College of Mechanical and Electrical Engineering Sichuan Agricultural UniversityYa’an 625014China

In response to the problems of numerous model parameters and low detection accuracy in SSD-based cotton leaf disease detection methods,a cotton leaf disease detection method based on improved SSD was proposed by combining the characteristics of cotton leaf ***,the lightweight network MobileNetV2 was introduced to improve the backbone feature extraction network,which provides more abundant semantic information and details while significantly reducing the amount of model parameters and computing complexity,and accelerates the detection speed to achieve real-time ***,the SE attention mechanism,ECA attention mechanism,and CBAM attention mechanism were fused to filter out disease target features and effectively suppress the feature information of jamming targets,generating feature maps with strong semantics and precise location *** test results on the self-built cotton leaf disease dataset show that the parameter quantity of the SSD_MobileNetV2 model with backbone network of MobileNetV2 was 50.9%of the SSD_VGG model taking VGG as the *** with SSD_VGG model,the P,R,F1 values,and mAP of the MobileNetV2 model increased by 4.37%,3.3%,3.8%,and 8.79%respectively,while FPS increased by 22.5 frames/*** SE,ECA,and CBAM attention mechanisms were introduced into the SSD_VGG model and SSD_MobileNetV2 *** gradient weighted class activation mapping algorithm to explain the model detection process and visually compare the detection results of each *** results indicate that the P,R,F1 values,mAP and FPS of the SSD_MobileNetV2+ECA model were higher than other models that introduced the attention ***,this model has less parameter with faster running speed,and is more suitable for detecting cotton diseases in complex environments,showing the best detection ***,the improved SSD_MobileNetV2+ECA model significantly enhanced the semantic information of the shallow feature map of the model,and has a goo

关键词： cotton disease detection SSD MobileNetV2 attention mechanism

A new method for identifying flow pattern of spouted fluidized bed by coupling Hilbert-Huang transform characteristics of differential pressure signals in different zones

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Particuology 2024年第6期89卷 67-78页

作者： Yongzhi Mei Yang Wang Lihui Zhang feng Duan School of Energy and Environment Anhui University of TechnologyMaanshan243002China Wuhu Technology and Innovation Research Institute Wuhu241000China Wuhu Cigarette Factory of China Tobacco Anhui Industrial Co. Ldt.Wuhu241002China

On a cold spouted fluidized bed,this study compares the characteristic differences in intrinsic mode function(IMF)energy and Hilbert–Huang spectrum between the spout zone and annulus zone under different combinations of spouted gas and fluidized gas flow rates for five typical flow *** energy distribution characteristics under different flow patterns are also *** Hilbert–Huang spectrum and IMF energy of pressure difference signals exhibit distinct variations in different zones as the flow pattern ***,there exists a correlation between the energy in the middle-frequency range and the flow *** the K-means algorithm,the middle-frequency range energy of IMFs in the spout zone and annulus zone is subjected to clustering analysis,leading to the identification of partition boundaries for each flow *** on this,a flow pattern identification method of spouted fluidized bed coupled with middle-frequency range energy in spout zone and annulus zone is proposed,which has very high identification accuracy.

关键词： Spouted fluidized bed Flow pattern Zoning signal Flow pattern transition Hilbert-Huang transform

Estimation of Hammerstein nonlinear systems with noises using filtering and recursive approaches for industrial control

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 260-271页

作者： Mingguang ZHANG feng LI Yang YU Qingfeng CAO School of Electrical&Information Engineering Jiangsu University of TechnologyChangzhou213001China College of Electrical Energy and Power EngineeringYangzhou UniversityYangzhou225127China

This paper discusses a strategy for estimating Hammerstein nonlinear systems in the presence of measurement noises for industrial control by applying filtering and recursive *** proposed Hammerstein nonlinear systems are made up of a neural fuzzy network(NFN)and a linear state`-space *** estimation of parameters for Hammerstein systems can be achieved by employing hybrid signals,which consist of step signals and random ***,based on the characteristic that step signals do not excite static nonlinear systems,that is,the intermediate variable of the Hammerstein system is a step signal with different amplitudes from the input,the unknown intermediate variables can be replaced by inputs,solving the problem of unmeasurable intermediate variable *** the presence of step signals,the parameters of the state-space model are estimated using the recursive extended least squares(RELS)***,to effectively deal with the interference of measurement noises,a data filtering technique is introduced,and the filtering-based RELS is formulated for estimating the NFN by employing random ***,according to the structure of the Hammerstein system,the control system is designed by eliminating the nonlinear block so that the generated system is approximately equivalent to a linear system,and it can then be easily controlled by applying a linear *** effectiveness and feasibility of the developed identification and control strategy are demonstrated using two industrial simulation cases.

关键词： Hammerstein nonlinear systems Neural fuzzy network Data filtering Hybrid signals Industrial control

Effect of hot isostatic pressure on the microstructure and tensile properties of γ'-strengthened superalloy fabricated through induction-assisted directed energy deposition

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1089-1097页

作者： Jianjun Xu Hanlin Ding Xin Lin feng Liu Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

The microstructure characteristics and strengthening mechanism of Inconel738LC(IN-738LC) alloy prepared by using induction-assisted directed energy deposition(IDED) were elucidated through the investigation of samples subjected to IDED under 1050℃ preheating with and without hot isostatic pressing(HIP,1190℃,105 MPa,and 3 h).Results show that the as-deposited sample mainly consisted of epitaxial columnar crystals and inhomogeneously distributed γ’ phases in interdendritic and dendritic core *** HIP,grain morphology changed negligibly,whereas the size of the γ’ phase became increasingly *** further heat treatment(HT,1070℃,2 h + 845℃,24 h),the γ’ phase in the as-deposited and HIPed samples presented a bimodal size distribution,whereas that in the as-deposited sample showed a size that remained *** comparison of tensile properties revealed that the tensile strength and uniform elongation of the HIP + HTed sample increased by 5% and 46%,respectively,due to the synergistic deformation of bimodal γ’phases,especially large cubic γ’ ***,the relationship between phase transformations and plastic deformations in the IDEDed sample was discussed on the basis of generalized stability theory in terms of the trade-off between thermodynamics and kinetics.

关键词： directed energy deposition Ni-based superalloys high-temperature preheating hot isostatic pressing microstructure tensile properties

Securing multi-chain consensus against diverse miner behavior attacks in blockchain networks

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Frontiers of Information Technology & Electronic Engineering 2024年第4期25卷 540-554页

作者： Wenbo ZHANG Tao WANG Chaoyang ZHANG Jingyu feng School of Cyberspace Security Xi’an University of Posts and TelecommunicationsXi’an 710121China Postal Savings Bank of China Xi’an 710000China

As cross-chain technologies enable interactions among different blockchains(hereinafter“chains”),multi-chain consensus is becoming increasingly important in blockchain ***,more attention has been paid to single-chain consensus ***-chain consensus schemes with trusted miner participation have not been considered,thus offering opportunities for malicious users to launch diverse miner behavior(DMB)attacks on different *** attackers can be friendly in the consensus process on some chains,called mask chains,to enhance their trust value,while on others,called kill chains,they engage in destructive behaviors on the *** this paper,we propose a multi-chain consensus scheme named Proof-of-DiscTrust(PoDT)to defend against DMB *** idea of distinctive trust(DiscTrust)is introduced to evaluate the trust value of each user across different *** trustworthiness of a user is split into local and global trust values.A dynamic behavior prediction scheme is designed to enforce DiscTrust to prevent an intensive DMB attacker from maintaining strong trust by alternately creating true or false blocks on the kill *** trusted miner selection algorithms for multi-chain environments can be implemented to select network miners,chain miners,and chain miner leaders,*** results show that PoDT is secure against DMB attacks and more effective than traditional consensus schemes in multi-chain environments.

关键词： Blockchain Cross-chain Trust mechanism Multi-chain consensus

High-efficiency crystalline white organic lightemitting diodes

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Light(Science & Applications) 2024年第4期13卷 747-759页

作者： Yijun Liu feng Zhu Yue Wang Donghang Yan State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China. School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China. State Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchun 130012China

Crystalline white organic light-emitting diodes(C-WOLEDs)are promising candidates for lighting and display *** is urgently necessary,however,to develop energy-saving and high-efficiency C-WOLEDs that have stable and powerful emission to meet commercial ***,we report a crystalline host matrix(CHM)with embedded nanoaggregates(NA)structure for developing high-performance C-WOLEDs by employing a thermally activated delayed fluorescence(TADF)material and orange phosphorescent dopants(Phos.-D).The CHM-TADFNA-D WOLED exhibit a remarkable EQE of 12.8%,which is the highest performance WOLEDs based on crystalline *** device has a quick formation of excitons and a well-designed energy transfer process,and possesses a fast ramping of luminance and current *** to recently reported high-performance WOLEDs based on amorphous material route,the C-WOLED achieves a low series-resistance Joule-heat loss ratio and an enhanced photon output,demonstrating its significant potential in developing the next-generation WOLEDs.

关键词： diodes dopant crystalline

Galectin 2 regulates JAK/STAT3 signaling activity to modulate oral squamous cell carcinoma proliferation and migration in vitro

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BIOCELL 2024年第5期48卷 793-801页

作者： XINRU feng LI XIAO Medical School University of Electronic Science and Technology of ChinaChengdu610072China Department of Stomatology Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu610072China

Background:Galectin 2(LGALS2)is a protein previously reported to serve as a mediator of disease progression in a range of *** function of LGALS2 in oral squamous cell carcinoma(OSCC),however,has yet to be explored,prompting the present study to address this literature ***:Overall,144 paired malignant tumor tissues and paracancerous OSCC patient samples were harvested and the LGALS2 expression levels were examined through qPCR and western *** LGALS2 coding sequence was introduced into the pcDNA3.0 vector,to enable the overexpression of this gene,while an LGALS2-specific shRNA and corresponding controls were also *** functionality of LGALS2 as a regulator of the ability of OSCC cells to grow and undergo apoptotic death in vitro was assessed through EdU uptake and CCK-8 assays,and flow cytometer,whereas a Transwell system was used to assess migratory activity and *** agonist of the Janus Kinase 2(JAK2)/Signal Transducer and Activator of Transcription 3(STAT3)pathway was also used to assess the role of this pathway in the context of LGALS2 ***:Here,we found that lower LGALS2 protein and mRNA expression were evident in OSCC tumor tissue samples,and these expression levels were associated with clinicopathological characteristics and patient survival *** LGALS2 enhanced proliferation in OSCC cells while rendering these cells better able to resist *** opposite was instead observed after LGALS2 was ***,the ability of LGALS2 to suppress the progression of OSCC was related to its ability to activate the JAK/STAT3 signaling ***:Those results suggest a role for LGALS2 as a suppressor of OSCC progression through its ability to modulate JAK/STAT3 signaling,supporting the potential utility of LGALS2 as a target for efforts aimed at treating OSCC patients.

关键词： LGALS2 Oral squamous cell carcinoma(OSCC) Janus Kinase 2/Signal Transducer and Activator of Transcription 3(JAK2-STAT3) Progression

AWells-Riley/based COVID-19 infectiousrisk assessment model combining both short rangeandroom scale effects

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Building Simulation 2024年第1期17卷 93-111页

作者： Yinshuai feng Yifan Fan Xiaoyu Luo Jian Ge College of Civil Engineering and Architecture Zhejiang UniversityHangzhouChina Center for Balance Architecture Zhejiang UniversityHangzhouChina International Research Center for Green Building and Low-Carbon City International CampusZhejiang UniversityHainingChina

There is growing evidence of the high transmission potential of COVID-19 through virus-laden *** aerosols are inhaled in various concentrations,an overall assessment of transmission risks at different indoor scales is ***,a comprehensive risk assessment method that evaluates the direct link between short-range and room-scale zones is stl *** this paper,a risk assessment model combining both short-range and room-scale effects is developed to obtain effective reproduction number in confined indoor environments,called Turbulent Jet Wells Riley(TJWR)*** with the viral load data and aerosol generation data of different human respiratory activities,the Monte Carlo simulation method is applied to calculate the quanta emission rate,which further provides the input parameters of the TJWR *** known outbreaks(Hangzhou banquet hall X,Guangzhou restaurant Y,and Hong Kong restaurant Z,China)are chosen to validate the TJWR *** show that the TJWR model is more efficient than the original Wells-Riley *** average relative error of the TJWR model ranges between 9%and 44%,while for the Wells-Riley model,it ranges between 57%and 78%.The TJWR model also proves that infection risk assessments using the well-mixed assumption can systematically underestimate the transmission risk for those close to the ***,there is a significant positive linear correlation between the total number of exposed individuals at the short-range and the effective reproduction *** newly developed TJWR model has great potential for rapid and real-time overall airborne transmission risk assessment in buildings and cities.

关键词： COVID-19 airborne transmission infection risk Wells-Riley model Monte Carlo simulation