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Enhancing Log Anomaly Detection with Semantic Embedding and Integrated Neural Network Innovations

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Computers, Materials and Continua 2024年第3期80卷 3991-4015页

作者： Xu Z. Wang Z. Xu j. Shi h. Zhao h. School of Computer and Software Nanjing University of Information Science and Technology Nanjing 210044 China

System logs, serving as a pivotal data source for performance monitoring and anomaly detection, play an indispensable role in assuring service stability and reliability. Despite this, the majority of existing log-based anomaly detection methodologies predominantly depend on the sequence or quantity attributes of logs, utilizing solely a single Recurrent Neural Network (RNN) and its variant sequence models for detection. These approaches have not thoroughly exploited the semantic information embedded in logs, exhibit limited adaptability to novel logs, and a single model struggles to fully unearth the potential features within the log sequence. Addressing these challenges, this article proposes a hybrid architecture based on a multiscale convolutional neural network, efficient channel attention and mogrifier gated recurrent unit networks (LogCEM), which amalgamates multiple neural network technologies. Capitalizing on the superior performance of robustly optimized BERT approach (RoBERTa) in the realm of natural language processing, we employ RoBERTa to extract the original word vectors from each word in the log template. In conjunction with the enhanced Smooth Inverse Frequency (SIF) algorithm, we generate more precise log sentence vectors, thereby achieving an in-depth representation of log semantics. Subsequently, these log vector sequences are fed into a hybrid neural network, which fuses 1D Multi-Scale Convolutional Neural Network (MSCNN), Efficient Channel Attention Mechanism (ECA), and Mogrifier Gated Recurrent Unit (GRU). This amalgamation enables the model to concurrently capture the local and global dependencies of the log sequence and autonomously learn the significance of different log sequences, thereby markedly enhancing the efficacy of log anomaly detection. To validate the effectiveness of the LogCEM model, we conducted evaluations on two authoritative open-source datasets. The experimental results demonstrate that LogCEM not only exhibits excellent ac

关键词： anomaly detection Deep learning log analysis natural language processing

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/CdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.Y.huang Z.Yang S.Y.Yang Z.h.Dai Y.j.Liu j.h.Liao G.Y.Zhong Z.j.Xie Y.P.Fang S.S.Zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/CdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure heterostructure Photothermal effect Photocatalyst hydrogen evolution

A vectorial model for the nonlinear gradient force exerted on metallic Rayleigh nanoparticles

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Chinese Optics Letters 2024年第2期22卷 207-213页

作者：朱政张聿全闵长俊 Aurèle j.LAdam h.Paul Urbach 袁小聪 Research Center for humanoid Sensing Research Institute of Intelligent SensingZhejiang LabHangzhou 311100China Nanophotonics Research Center Institute of Microscale Optoelectronics&State Key Laboratory of Radio Frequency Heterogeneous IntegrationShenzhen UniversityShenzhen 518060China Optics Research Group ImPhys DepartmentFaculty of Applied SciencesDelft University of TechnologyDelft 2628 CJThe Netherlands

Optical tweezers have proved to be a powerful tool with a wide range of *** gradient force plays a vital role in the stable optical trapping of *** scalar method is convenient and effective for analyzing the gradient force in traditional optical ***,when the third-order nonlinear effect of the nano-object is stimulated,the scalar method cannot adequately present the optical response of the metal nanoparticle to the external optical ***,we propose a theoretical model to interpret the nonlinear gradient force using the vector *** combining the optical Kerr effect,the polarizability vector of the metallic nanoparticle is derived.A quantitative analysis is obtained for the gradient force as well as for the optical potential *** vector method yields better agreement with reported experimental *** suggest that this method could lead to a deeper understanding of the physics relevant to nonlinear optical trapping and binding phenomena.

关键词： gradient forces nonlinear effect metallic nanoparticles

Greatly enhanced corrosion/wear resistances of epoxy coating for Mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer

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journal of Magnesium and Alloys 2024年第1期12卷 332-344页

作者： Z.Y.Xue X.j.Li j.h.Chu M.M.Li D.N.Zou L.B.Tong School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a double-layer epoxy composite coating on Mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)*** FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloys.

关键词： Mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance Blocking layer

Synchronized off-harmonic probe laser with highly variable pulse duration for laser-plasma interaction experiments

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high Power Laser Science and Engineering 2024年第1期12卷 99-107页

作者： j.hornung Y.Zobus h.Lorenté C.Brabetz B.Zielbauer V.Bagnoud GSI helmholtzzentrum für Schwerionenforschung Gmbh DarmstadtGermany Institut d’Optique UniversitéParis-SaclayPalaiseauFrance Institut für Angewandte Physik Technische Universität DarmstadtDarmstadtGermany

This paper presents the development and experimental utilization of a synchronized off-harmonic laser system designed as a probe for ultra-intense laser±plasma interaction experiments. The system exhibits a novel seed-generation design,allowing for a variable pulse duration spanning over more than three orders of magnitude, from 3.45 picoseconds to 10 nanoseconds. This makes it suitable for various plasma diagnostics and visualization techniques. In a side-view configuration, the laser was employed for interferometry and streaked shadowgraphy of a laser-induced plasma while successfully suppressing the self-emission background of the laser±plasma interaction, resulting in a signal-to-self-emission ratio of 110 for this setup. These properties enable the probe to yield valuable insights into the plasma dynamics and interactions at the PhELIX facility and to be deployed at various laser facilities due to its easy-to-implement design.

关键词： interferometry laser-plasma interaction off-harmonic probe laser streaked shadowgraphy

Schisanhenol ameliorates non-alcoholic fatty liver disease via inhibiting miR-802 activation of AMPK-mediated modulation of hepatic lipid metabolism

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Acta Pharmaceutica Sinica B 2024年第9期14卷 3949-3963页

作者： Li B. Xiao Q. Zhao h. Zhang j. Yang C. Zou Y. Zhang B. Liu j. Sun h. Liu h. State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Medicinal Plant Development Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100193 China Institute of Basic Medical Sciences Chinese Academy of Medical Sciences Department of Pathophysiology Peking Union Medical College Beijing 100005 China

Non-alcoholic fatty liver disease (NAFLD), characterized by hepatic steatosis, is a common metabolic liver disease worldwide. Currently, satisfactory drugs for NAFLD treatment remain lacking. Obesity and diabetes are the leading causes of NAFLD, and compounds with anti-obesity and anti-diabetic activities are considered suitable candidates for treating NAFLD. In this study, biochemical and histological assays revealed that a natural lignan schisanhenol (SAL) effectively decreased lipid accumulation and improved hepatic steatosis in free fatty acid (FFA)-treated hepG2 cells and high-fat diet (hFD)-induced NAFLD mice. Further, molecular analyses, microRNA (miRNA)-seq, and bioinformatics analyses revealed that SAL may improve NAFLD by targeting the miR-802/adenosine monophosphate-activated protein kinase (AMPK) pathway. Liver-specific overexpression of miR-802 in NAFLD mice significantly impaired SAL-mediated liver protection and decreased the protein levels of phosphorylated (p)-AMPK and PRKAB1. Dual-luciferase assay analysis further confirmed that miR-802 inhibits hepatic AMPK expression by binding to the 3' untranslated region of mouse Prkab1 or human PRKAA1. Additionally, genetic silencing of PRKAA1 blocked SAL-induced AMPK pathway activation in FFA-treated hepG2 cells. The results demonstrate that SAL is an effective drug candidate for treating NAFLD through regulating miR-802/AMPK-mediated lipid metabolism. © 2024 The Authors

关键词： AMPK hepatic steatosis Lipid metabolism miR-802 Non-alcoholic fatty liver disease PPARα Schisanhenol SREBP-1c

hybrid robust fault detection and isolation of satellite reaction wheel actuators

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journal of Control and Decision 2024年第1期11卷 117-131页

作者： h.Abbasi Nozari S.j.Sadati Rostami Paolo Castaldi Silvio Simani Faculty of Electrical and Computer Engineering Babol Noshirvani University of TechnologyBabolIran Department of Electrical Electronic and Information EngineeringUniversity of BolognaCesenaItaly Department of Engineering University of FerraraFerraraItaly

In this paper,a combined robust fault detection and isolation scheme is studied for satellite system subject to actuator faults,external disturbances,and parametric *** proposed methodology incorporates a residual generation module,including a bank of filters,into an intelligent residual evaluation ***,residual filters are designed based on an improved nonlinear differential algebraic approach so that they are not affected by external *** residual evaluation module is developed based on the suggested series and parallel ***,a new ensemble classification scheme defined as blended learning integrates heterogeneous classifiers to enhance the performance.A wide range of simulations is carried out in a high-fidelity satellite simulator subject to the constant and time-varying actuator faults in the presence of disturbances,manoeuvres,uncertainties,and *** obtained results demonstrate the effectiveness of the proposed robust fault detection and isolation method compared to the traditional nonlinear differential algebraic approach.

关键词： Robust fault detection and isolation reaction wheels blended learning series and parallel fault detection and isolation forms satellite attitude control system

A detailed comparison of the composition of(RE)-Ba-Cu-O-Ag bulk superconductors

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Superconductivity 2024年第1期9卷 87-94页

作者： j.V.j.Congreve Y.Shi A.R.Dennis h.Druiff N.C.Tutt D.A.Cardwell j.h.Durrell Department of Engineering University of CambridgeCambridgeUK

The homogeneity of the microstructure and composition are critical in determining the properties of rare earthbarium‐cuprate,single grain bulk superconductors[(RE)BCO].The magnitude of the trapped magnetic field achieveable in these technologically important materials,in particular,is influenced heavily by the size and distribution of(RE)_(2)BaCuO_(x)(RE‐211)flux pinning inclusions in the bulk microstructure,whereas the size and distribution of silver agglomerates present within the bulk superconducting matrix correlate directly with improved mechanical *** careful engineering,these materials have significant potential for application in range of devices related to energy storage,medicine,electro‐magnetic machinery and microelectronic *** of(RE)BCO bulk superconductors typically involves heating a powder compact above its peritectic decomposition temperature followed by slow cooling to facilitate the growth of a single ***(RE)BCO composition has a different peritectic temperature and growth rate,which,therefore,necessitates different requirements in the heating *** fabrication temperature and growth rate,for example,may have an effect on the RE‐211 and silver distribution,which may,in turn,affect the superconducting properties of the resulting single *** this work we compare the distributions of silver and RE‐211 in the single grain microstructures of YBCOAg,GdBCO‐Ag,EuBCO‐Ag and SmBCO‐Ag bulk superconductors using optical microscopy,scanning electron microscopy and energy dispersive X‐ray *** observe that the distributions are very similar along both the a/b‐axis and c‐axis of these *** suggests that factors other than the maximum temperature used to achieve peritectic decomposition and the rate of single grain growth are particularly influential in determining the properties of the as‐processed samples in the top seeded melt growth *** observation demonstrates there is freedom to us

关键词： YBCO‐Ag GdBCO‐Ag SmBCO‐Ag EuBCO‐Ag Composition Bulk superconductor

Effects of pyrethroid and organophosphate insecticides on reared black soldier fly larvae(hermetia illucens)

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Insect Science 2024年第3期31卷 817-834页

作者： Nathan Meijer Lisa Zoet Theo de Rijk Paul Zomer Deborah Rjkers h.j.van der Fels-Klerx joop j.A.van Loon Wageningen Food Safety Research(WFSR) Part of Wageningen University and ResearchWageningenThe Netherlands Bestico B.V. Industrieweg 6Berkel en RodenrjsThe Netherlands Plant Sciences Group Laboratory of EntomologyWageningen UniversityWageningenTheNetherlands

Black soldier fly larvae(hermetia illucens)receive growing interest as a potential alternative animal feed *** insects may be exposed to insecticide residues in the rearing *** study aimed to investigate the effects of six different pyrethroid and organophosphate insecticides on this insect species'*** toxicity of two"model"substances for each of these classes(cypermethrin;pirimiphosmethyl)was quantified,with and without the synergist piperonyl butoxide(PBO).Critical effect doses corresponding to 10%yield(CED10)for cypermethrin(0.4 mg/kg)and pirimiphos-methyl(4.8 mg/kg)were *** addition of PBO to cypermethrin enhanced its relative potency with a factor *** data were compared against the relative toxicity of two analogue substances in each class(permethrin,deltamethrin;chlorpyrifosmethyl,malathion).Results suggest that exposure to concentrations complying with legal limits can cause significant reductions in *** to multiple substances at lower concentrations resulted in negative additive and synergistic *** the tested substances,deltamethrin was most toxic,causing 94%yield at 0.5 mg/*** results suggested that transfer of tested substances to the larval biomass was substance-and concentration-specific,but appeared to be correlated to reduced yields and the presence of *** of organophosphates was overall low(high transfer may result in *** is recommended that rearing companies implement lower contractual thresholds,and that policymakers consider adjusting legally allowed maximum residue levels in insect feed.

关键词： feed insects pesticides rearing substrate