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

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

作者： xu z. Wang z. xu J. Shi H. z.ao 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, utiliz.ng 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. Capitaliz.ng on the superior performance of robustly optimiz.d 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

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NUMERICAL STUDY OF TURBULENT IMPINGING JET WITH A REFINED k-ε MODEL

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Journal of Hydrodynamics 2000年第4期12卷 8-15页

作者： xu, J.L. xu, z. Huang, S.J. z.ang, K.Y. Xiao, M. 2nd Dep. Nanjing Univ. of Aeron. and Astron. Nanjing 210016 China

A refined k-Ε model re-considering the fluctuating pressure diffusion term in the dissipation rate equation (Ε-equation) is provided and used in the numerical study of circular semi-confined turbulent impinging jet. The results are compared with those of the standard k-Ε model and show that the predicting ability of the refined k-Ε model is much improved, especially for the turbulent kinetic energy k. So it is necessary to consider the effect of the fluctuating pressure diffusion term and to model this term correctly and exactly in the near wall region with the great adverse pressure gradient, where the effect of the pressure fluctuating is important. Therefore we can conclude that the new modeling idea expressed in this paper is correct and effective.

关键词： Computer simulation Jets Mathematical models Turbulence

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Observation　and　identification　of　X－ray（0．3－30Bnm)　multiple－order　diffraction　spectra

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Chinese Journal of Lasers 1994年第5期B3卷 413-420页

作者： FENG X. P HOU X. B z.ANG z. Q xu z. z.(Shanghai Institute of Optics and Fine Mechanics,Acdemaia Sinica, P. O. Box 800-211, Shanghai 201800, China) Shanghai Inst of Optics and Fine Mechanics Academia Sinica Shanghai China

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ＯｂｓｅｒｖａｔｉｏｎａｎｄｉｄｅｎｔｉｆｉｃａｔｉｏｎｏｆＸ－ｒａｙ（０．３－３０ｎｍ）ｍｕｌｔｉｐｌｅ－ｏｒｄｅｒｄｉｆｆｒａｃｔｉｏｎｓｐｅｃｔｒａＦＥＮＧＸ．Ｐ；ＨＯＵＸ．Ｂ；ＺＨＡＮＧＺ．Ｑ；ＸＵＺ．Ｚ．（ＳｈａｎｇｈａｉＩｎｓｔｉｔｕｔｅ...

关键词： X-ray spectra laser plasma

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DIFFERENTIAL SCANNING CALORIMETRY AND X-RAY DIFFRACTION STUDIES ON AGING BEHAVIOR OF z.-Al ALLOYS

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 109-114页

作者： X.L. xu, z. W. Yu, S.J. Ji, J.C. Sun and z.K. Hei (Dalian Maritime University, Dalian 116024, China) Dalian Maritime University

Decomposition processes of the quenched z.-Al alloys were studied by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results show that the stabilities of supersaturated solid solution (SSS) of z.-Al alloy and α' phase formed by quenching would reduce with the increase of z. content and the precipitation of η-z. phases even when aging at ambient temperature, so that the exothermic precipitation peak in DSC curve would disappear. The activation energy of the η-z. precipitation and the reaction enthalpy were calculated and measured. The kinetics of α' decomposition or η-z. formation was determined by XRD. The microstructure change during aging was observed by TEM.

关键词： Aging of materials Aluminum alloys Differential scanning calorimetry X ray diffraction

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STUDY ON THE CONTROLLED MASS TRANSPORT THROUGH POROUS MEMBRANES

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化工学报 2000年第S1期51卷 15-19页

作者： xu Xia and Cui z. F (Department of Engineering Scinece, University of Oxford,OXI 3PJ, UK)

Cryopreservation of cells and tissues (natural or engineered) usually involves complicated protocols for addition and later removal of cryoprotecting agents to avoid osmotic shock and toxicity to cells. The rate of CPA addition and removal is essential to cell survival. In this study, the feasibility of using porous membrane to control the rate of CPA transfer to cell environment is studied, A purpose designed diffusion chamber was fabricated. The effects of membrane characteristics (porosity and effective thickness), temperature, and initial concentration were experimentally studied. A simplified mathematical model was developed, which provides the basis to desire the membrane parameters based on tile experimental measurements.

关键词： mass transport membranes diffusion rate control cryopreservation

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The Effect of Procrastination on Physical Exercise among College Students—The Chain Effect of Exercise Commitment and Action Control

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International Journal of Mental Health Promotion 2024年第8期26卷 611-622页

作者： z.ang W. xu M. Feng Y. Mao z. Yan z. Department of Physical Education Qufu Normal University Qufu 273165 China Department of Internal Medicine The Ohio State University Columbus 43210 OH United States Teaching Department of Common Courses Shandong University of Art & Design Jinan 250399 China School of Psychology Beijing Sport University Beijing 100084 China School of Physical Education Chongqing University of Posts and Telecommunications Chongqing 400065 China

Background: Exercise procrastination is prevalent among college students, causing decline in physical fitness. It is imperative to investigate the mechanism affecting college students’ physical activity behaviors. This study was aimed at investigating the effect of procrastination on college students’ physical exercise behavior, and the chain mediation effects of exercise commitment and action control (AC), to provide a theoretical basis for interventions targeting physical exercise behavior among college students. Methods: A questionnaire survey was conducted using convenience sampling. The General Procrastination Scale, Exercise Commitment Scale, Action Control Scale, and Physical Activity Rating Scale-3 questionnaires were used. Participants were 581 college students (age 19.27 ± 0.94 years; 243 males and 338 females). Statistical methods of regression analysis and structural equation modeling (SEM) were applied. Results: Procrastination, exercise commitment, and action control were found to be significant predictors of physical exercise behavior. Among these predictors, exercise commitment and action control showed full mediation effects in the relationship between procrastination and physical exercise behavior, and explained 25.48% and 30.77% of the total variance, respectively. The chain mediation effect of exercise commitment-action control was significant, accounting for 22.60% of the total variance, and the total indirect effect was 79.33%. Conclusion: Therefore, higher procrastination was associated with less participation in physical exercise behavior among college students. Improvements in exercise commitment and volitional decision-making ability for physical exercise behavior promoted physical exercise behavior, and increased exercise commitment promoted volitional decision-making ability among the students. The chain reaction effect of exercise commitment and action control also buffered the negative effects of procrastination on physical exercise beh

关键词： action control chain intermediary College student exercise behavior exercise commitment procrastination

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Quantitative Identification of Delamination Damage in Composite Structure Based on Distributed Optical Fiber Sensors and Model Updating

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SDHM Structural Durability and Health Monitoring 2024年第6期18卷 785-803页

作者： xu H. Wang J. z.u R. Strauss A. Cao M. Wu z. School of Materials Science and Engineering Dalian University of Technology Dalian 116000 China School of Mechanics and Aerospace Engineering Dalian University of Technology Dalian 116000 China Department of Civil Engineering and Natural Haz.rds University of Natural Resources and Life Sciences Vienna 1180 Austria Department of Engineering Mechanics Hohai University Nanjing China

Delamination is a prevalent type of damage in composite laminate structures. Its accumulation degrades structural performance and threatens the safety and integrity of aircraft. This study presents a method for the quantitative identification of delamination identification in composite materials, leveraging distributed optical fiber sensors and a model updating approach. Initially, a numerical analysis is performed to establish a parameteriz.d finite element model of the composite plate. Then, this model subsequently generates a database of strain responses corresponding to damage of varying siz.s and locations. The radial basis function neural network surrogate model is then constructed based on the numerical simulation results and strain responses captured from the distributed fiber optic sensors. Finally, a multi-island genetic algorithm is employed for global optimiz.tion to identify the siz. and location of the damage. The efficacy of the proposed method is validated through numerical examples and experiment studies, examining the correlations between damage location, damage siz., and strain responses. The findings confirm that the model updating technique, in conjunction with distributed fiber optic sensors, can precisely identify delamination in composite structures. © 2024 The Authors. Published by Tech Science Press.

关键词： Composite structures damage identification fiber optic sensor model updating surrogate model

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电介质材料和物理专题编者按

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物理学报 2020年第12期69卷 1-1页

作者： Li X.-G. xu z.

电介质材料有许多独特的物理性质,如介电、压电、热释电、铁电、电光、非线性光学及其耦合特性等,在传感、换能、探测、医疗、通信、国防等众多领域具有广泛的应用价值.相关的物理研究主要涉及介电材料内部束缚电荷在电、磁、光、力、... 详细信息

电介质材料有许多独特的物理性质,如介电、压电、热释电、铁电、电光、非线性光学及其耦合特性等,在传感、换能、探测、医疗、通信、国防等众多领域具有广泛的应用价值.相关的物理研究主要涉及介电材料内部束缚电荷在电、磁、光、力、热等外场作用下的极化过程和与极化相关的各种物理现象;通过设计材料的成分与结构等,揭示诸多性能的调控规律和微观机制,在此基础上开发高性能电子器件.

关键词：电介质材料非线性光学物理现象极化过程束缚电荷介电材料外场作用微观机制

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激光熔覆制备金属间化合物抗冲蚀涂层

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航空制造技术 2004年第Z1期47卷 79-81,122页

作者： X.Y. xu W.J. Liu M.L. z.ong H.Q. Sun X.Y. xu R. z. Ba

采用同轴送粉方法,激光熔覆制备了WC增强Ni3Al金属间化合物基复合涂层,通过试验,优化了工艺参数,对激光熔覆涂层的成分、组织和硬度进行了测试和分析.结果表明,激光熔覆涂层无裂纹和气孔,与基体形成良好的冶金结合,WC颗粒的添加显著提... 详细信息

采用同轴送粉方法,激光熔覆制备了WC增强Ni3Al金属间化合物基复合涂层,通过试验,优化了工艺参数,对激光熔覆涂层的成分、组织和硬度进行了测试和分析.结果表明,激光熔覆涂层无裂纹和气孔,与基体形成良好的冶金结合,WC颗粒的添加显著提高了涂层硬度.

关键词：激光熔覆金属间化合物镍铝化合物

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Excitonic character of nanometer z.O films prepared by thermaloxidation of z.S films

Excitonic character of nanometer ZnO films prepared by therm...

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第九届全国发光学术会议

作者： X. T. z.ang, Y. C. Liu. z. z. z.i, J. Y. z.ang, Y. M. Lu, W. xu, D. z. Shen, G. z. z.ong, X. W. Fan and X. G. Kong Open Laboratory of Excited State Processes, Chinese Academy of Science, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Science, 1- Yan An Road, Changchun, 130021, P. R. China

As a wide band gap (Eg=3.37 eV), z.O has attracted considerable attention due to potentialapplications, such as ultraviolet light-emitting devices and laser devices. A large exciton binding energy (59 eV)permits excit...

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