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Sparse representation scheme with enhanced medium pixel intensity for face recognition

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 116-127页

作者： Xuexue Zhang Yongjun Zhang Zewei Wang Wei long Weihao gao Bob Zhang State Key Laboratory of Public Big Data Institute for Artificial IntelligenceCollege of Computer Science and TechnologyGuizhou UniversityGuiyangGuizhouChina Department of Computer and Information Science University of MacaoAvenida da UniversidadeTaipaMacaoChina

Sparse representation is an effective data classification algorithm that depends on the known training samples to categorise the test *** has been widely used in various image classification *** in sparse representation means that only a few of instances selected from all training samples can effectively convey the essential class-specific information of the test sample,which is very important for *** deformable images such as human faces,pixels at the same location of different images of the same subject usually have different ***,extracting features and correctly classifying such deformable objects is very ***,the lighting,attitude and occlusion cause more *** the problems and challenges listed above,a novel image representation and classification algorithm is ***,the authors’algorithm generates virtual samples by a non-linear variation *** method can effectively extract the low-frequency information of space-domain features of the original image,which is very useful for representing deformable *** combination of the original and virtual samples is more beneficial to improve the clas-sification performance and robustness of the ***,the authors’algorithm calculates the expression coefficients of the original and virtual samples separately using the sparse representation principle and obtains the final score by a designed efficient score fusion *** weighting coefficients in the score fusion scheme are set entirely ***,the algorithm classifies the samples based on the final *** experimental results show that our method performs better classification than conventional sparse representation algorithms.

关键词： computer vision face recognition image classification image representation

Landslide Displacement Prediction Based on Time Series and PSO-BP Model in Three Georges Reservoir, China

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Journal of Earth Science 2024年第3期35卷 1079-1082页

作者： Dexiang gao Kou Li Yuncheng Cai Tao wen School of Geosciences Yangtze UniversityWuhan 430100China School of Science Yunnan Agricultural UniversityKunming 650201China

0 INTRODUCTION Landslides are one of the most frequent geological disasters in the world(wen et al.,2020;Froude and Petley,2018),which have occurred frequently and widely distributed in China for a long *** landslides are essentially a complex multidimensional nonlinear dynamic system affected by its own geological conditions and external factors(Ma et al.,2021;Wang et al.,2019),including geotechnical characteristics,hydrogeology,geomorphologic conditions,climate,and weathering(Ma et al.,2020).The interaction of these factors makes the change of landslide displacement random,fuzzy and variable(Park and Michalowski,2017),and also brings great difficulties to the landslide displacement prediction(Ma et al.,2018).

关键词： landslide Landslide weathering

Asymptotic normality of error density estimator in stationary and explosive autoregressive models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 140-158页

作者： WU Shi-peng YANG wen-zhi gao Min HU Shu-he School of Mathematical Sciences&School of Big Data and Statistics Anhui UniversityHefei 230601China School of Statistics Shanxi University of Finance and EconomicsTaiyuan030006China

In this paper,we consider the limit distribution of the error density function estima-tor in the rst-order autoregressive models with negatively associated and positively associated random *** mild regularity assumptions,some asymptotic normality results of the residual density estimator are obtained when the autoregressive models are stationary process and explosive *** order to illustrate these results,some simulations such as con dence intervals and mean integrated square errors are provided in this *** shows that the residual density estimator can replace the density\estimator"which contains errors.

关键词： explosive autoregressive models residual density estimator asymptotic distribution association sequence

Assessment of the Southern Ocean Sea Surface Temperature Biases in CMIP5 and CMIP6 Models

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Journal of Ocean University of China 2024年第5期23卷 1135-1150页

作者： gao Zhen ZHAO Shichang LIU Qinyu long Shang-Min SUN Shantong Key Laboratory of Marine Hazards Forecasting Ministry of Natural Resources Hohai University College of Oceanography Hohai University Laoshan Laboratory Physical Oceanography Laboratory Ocean University of China

This work evaluates the performances of climate models in simulating the Southern Ocean(SO) sea surface temperature(SST) by a large ensemble from phases 5 and 6 of the Coupled Model Intercomparison Project(CMIP5 and CMIP6). By combining models from the same community sharing highly similar SO SST biases and eliminating the effect of global-mean biases on local SST biases, the results reveal that the ensemble-mean SO SST bias at 70° – 30°S decreases from 0.38℃ in CMIP5 to 0.28℃ in CMIP6, together with increased intermodel consistency. The dominant mode of the intermodel variations in the zonal-mean SST biases is characterized as a meridional uniform warm bias pattern, explaining 79.1% of the intermodel variance and exhibiting positive principal values for most models. The ocean mixed layer heat budget further demonstrates that the SST biases at 70° – 50°S primarily result from the excessive summertime heating effect from surface net heat flux. The biases in surface net heat flux south of 50°S are largely impacted by surface shortwave radiation from cloud and clear sky components at different latitudes. North of 50°S, the underestimated westerlies reduce the northward Ekman transport and hence northward cold advection in models, leading to warm SST biases year-round. In addition, the westerly biases are primarily traced back to the atmosphere-alone model simulations forced by the observed SST and sea ice. These results disclose the thermal origin at the high latitude and dynamical origin at the low latitude of the SO SST biases and underscore the significance of the deficiencies of atmospheric models in producing the SO SST biases.

关键词： atmospheric biases cloud simulation CMIP5 CMIP6 Southern Ocean SST biases surface heat flux westerlies

BL03HB: a Laue microdiffraction beamline for both protein crystallography and materials science at SSRF

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Nuclear Science and Techniques 2024年第7期35卷 68-78页

作者： Zhi-Jun Wang Si-Sheng Wang Zheng-Huang Su Li Yu Yu-Zhu Wang Bo Sun wen wen Xing-Yu gao Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China University of Chinese Academy of Science Beijing100049China

A Laue microdiffraction beamline(BL03HB) was constructed at the Shanghai Synchrotron Radiation Facility(SSRF).This beamline features two consecutive focusing points in two different sectors within its end station, the first dedicated to protein crystallography and the other tailored to materials science applications. Based on a superbend dipole magnet with a magnetic field of 2.29 T, a two-stage focusing design was implemented with two sets of Kirkpatrick-Baez mirrors to achieve a micro white beam as small as 4.2 μ m ×4.3 μ m at the first sector and 0.9 μ m ×1.3 μ m at the second sector in the standard beamline operation mode at SSRF. The X-ray microbeam in the two sectors can be easily switched between monochromatic and white beams by moving a four-bounce monochromator in or out of the light path, respectively. In the protein crystallography sector, white-beam Laue microdiffraction was demonstrated to successfully determine the structure of protein crystals from only a few images of diffraction data collected by a Pilatus 2 M area detector. In the materials science sector,the white-beam Laue diffraction was collected in a reflection geometry using another Pilatus 2 M area detector, which could map the microstructural distribution on the sample surface by scanning the samples. In general, the BL03HB beamline promotes the application of Laue microdiffraction in both protein crystallography and materials science. This paper presents a comprehensive overview of the BL03HB beamline, end station, and the first commission results.

关键词： Crystallography White-beam Laue microdiffraction Beamline Synchrotron

Two positive effects with one arrow:Modulating crystal and interfacial decoration towards high-potential cathode material

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Journal of Energy Chemistry 2024年第5期92卷 216-223页

作者： Xuexiu Gu Xuan-wen gao Dongrun Yang Qinfen Gu YSong Hong Chen Tianzhen Ren wen-Bin Luo Institute for Energy Electrochemistry and Urban Mines Metallurgy School of MetallurgyNortheastern UniversityShenyang 110819LiaoningChina Australian Synchrotron(ANSTO) 800 Blackburn RdClaytonVictoria 3168Australia School of Science and Engineering University of DundeeNethergateDundee DD14HNScotlandUK

As the primary suppliers of cyclable sodium ions,O3-type layer-structured manganese-based oxides are recognized as highly competitive cathode candidates for sodium-ion *** advance the development of high-energy sodium-ion batteries,it is crucial to explore cathode materials operating at high voltages while maintaining a stable cycling *** orbital and electronic structure of the octahedral center metal element plays a crucial role in maintaining the octahedra structural integrity and improving Na^(+)ion diffusion by introducing heterogeneous chemical *** by the abundant configuration of extra nuclear electrons and large ion radius,we employed trace amounts of tungsten in this *** obtained cathode material can promote the reversibility of oxygen redox reactions in the high-voltage region and inhibit the loss of lattice ***,the formation of a Na_(2)WO_(4) coating on the material surface can improve the interfacial stability and interface ions *** demonstrates an initial Coulombic efficiency(ICE)of 94.6%along with 168.5 mA h g^(-1 )discharge capacity within the voltage range of 1.9-4.35 *** findings contribute to the advancement of high-energy sodium-ion batteries by providing insights into the benefits of tungsten doping and Na_(2)WO_(4) coating on cathode materials.

关键词： Sodium ion battery Layer-structured manganese-based oxides Cathodematerial Surface modification Elements doping

Significantly Enhanced Melt Memory Effect of Metallocene-made Isotactic Polypropylene Containing Talc

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Chinese Journal of Polymer Science 2024年第2期42卷 213-222,I0008页

作者： Hong-wen Sun Fu-Shan Wang Yan gao Fu-Qing Wei Jia-Chun Feng State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China Lanzhou Petrochemical Corporation of PetroChina Lanzhou730060China Lanzhou Petrochemical Research Center Petrochemical Research Institute of PetroChinaLanzhou730060China

The melt memory effect is a widely observed phenomenon in semi-crystalline polymers. In practical applications, various additives are usually introduced into polymers, which may affect their melt memory behavior. In this work, the effect of talc on the melt memory effect of metallocene-made isotactic polypropylene(M-PP) was investigated in detail by using the differential scanning calorimetry. The results indicated that the introduction of talc significantly strengthened the melt memory effect of M-PP. Specifically, the upper limit temperature of Domain II increased from 161 ℃ to 174 ℃, resulting in a substantial widening of the temperature range of Domain IIa from 1 ℃ to 14 ℃. Analysis of the crystal orientation of the M-PP containing talc cooled from various Ts suggested that the remarkably enhanced melt memory effect could be ascribed to the stabilization of oriented nuclei facilitated by talc. This stabilizing effect was likely attributable to the prefreezing effect or the sorption interaction between talc and the M-PP chains.

关键词： Metallocene-made isotactic polypropylene Talc Melt memory effect Crystal orientation

3D core-shell nanofibers framework and functional ceramic nanoparticles synergistically reinforced composite polymer electrolytes for high-performance all-solid-state lithium metal battery

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Chinese Chemical Letters 2024年第8期35卷 425-432页

作者： Hengying Xiang Nanping Deng Lu gao wen Yu Bowen Cheng Weimin Kang State Key Laboratory of Separation Membranes and Membrane Processes Tiangong UniversityTianjin 300387China School of Textile Science and Engineering Tiangong UniversityTianjin 300387China

Satisfactory ionic conductivity,excellent mechanical stability,and high-temperature resistance are the prerequisites for the safe application of solid polymer electrolytes(SPEs)in all-solid-state lithium metal batteries(ASSLMBs).In this study,a novel poly(m-phenylene isophthalamide)(PMIA)-core/poly(ethylene oxide)(PEO)-shell nanofiber membrane and the functional Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)ceramic nanopar-ticle are simultaneously introduced into the PEO-based SPEs to prepare composite polymer electrolytes(CPEs).The core PMIA layer of composite nanofibers can greatly improve the mechanical strength and thermal stability of the CPEs,while the shell PEO layer can provide the 3D continuous transport channels for lithium *** addition,the introduction of functional LLZTO nanoparticle not only reduces the crys-tallinity of PEO,but also promotes the dissociation of lithium salts and releases more Li^(+)ions through its interaction with the Lewis acid-base of anions,thereby overall improving the transport of lithium ***,the optimized CPEs present high ionic conductivity of 1.38×10^(−4)S/cm at 30℃,signifi-cantly improved mechanical strength(8.5 MPa),remarkable thermal stability(without obvious shrinkage at 150℃),and conspicuous Li dendrites blocking ability(>1800 h).The CPEs also both have good com-patibility and cyclic stability with LiFePO_(4)(>2000 cycles)and high-voltage LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811)(>500 cycles)*** addition,even at low temperature(40℃),the assembled LiFePO4/CPEs/Li bat-tery still can cycle *** novel design can provide an effective way to exploit high-performance solid-state electrolytes.

关键词： Composite polymer electrolytes Core-shell structured nanofiber Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)ceramic nanoparticle All-solid-state lithium metal batteries Outstanding thermal stability and electrochemical performance

Gut liver brain axis in diseases:the implications for therapeutic interventions

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Signal Transduction and Targeted Therapy 2024年第1期9卷 79-104页

作者： Mengyao Yan Shuli Man Benyue Sun long Ma Lanping Guo Luqi Huang wenyuan gao State Key Laboratory of Food Nutrition and Safety Key Laboratory of Industrial MicrobiologyMinistry of EducationTianjin Key Laboratory of Industry MicrobiologyNational and Local United Engineering Lab of Metabolic Control Fermentation TechnologyChina International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal ChemistryCollege of BiotechnologyTianjin University of Science&Technology300457 TianjinChina National Resource Center for Chinese Materia Medica China Academy of Chinese Medical Sciences100700 BeijingChina Tianjin Key Laboratory for Modern Drug Delivery&High-Efficiency School of Pharmaceutical Science and TechnologyTianjin UniversityWeijin Road300072 TianjinChina

Gut-liver-brain axis is a three-way highway of information interaction system among the gastrointestinal tract,liver,and nervous *** the past few decades,breakthrough progress has been made in the gut liver brain axis,mainly through understanding its formation mechanism and increasing treatment *** this review,we discuss various complex networks including barrier permeability,gut hormones,gut microbial metabolites,vagus nerve,neurotransmitters,immunity,brain toxic metabolites,β-amyloid(Aβ)metabolism,and epigenetic regulation in the gut-liver-brain *** therapies containing antibiotics,probiotics,prebiotics,synbiotics,fecal microbiota transplantation(FMT),polyphenols,low FODMAP diet and nanotechnology application regulate the gut liver brain ***,some special treatments targeting gut-liver axis include farnesoid X receptor(FXR)agonists,takeda G protein-coupled receptor 5(TGR5)agonists,glucagon-like peptide-1(GLP-1)receptor antagonists and fibroblast growth factor 19(FGF19)*** gut-brain axis embraces cognitive behavioral therapy(CBT),antidepressants and tryptophan metabolism-related *** liver-brain axis contains epigenetic regulation and Aβmetabolism-related *** the future,a better understanding of gut-liver-brain axis interactions will promote the development of novel preventative strategies and the discovery of precise therapeutic targets in multiple diseases.

关键词： metabolism therapeutic immunity