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Frontiers of Structural and Civil Engineering 2024年第2期18卷 170-183页

作者： r.MOHANA S.M.Leela BHArATHI department of Civil Engineering Mepco Schlenk Engineering CollegeSivakasi 626123India

The hazardous environmental effects of greenhouse gas emissions and climate change demand alternative sources for cementitious materials in the construction *** development of geopolymer structures provides a way of producing 100%cement-free *** this research work,a novel and simple way of d.riving nano particles from waste fly ash particles is *** effect of adding the synthesized nano fly ash particles as a filler medium in geopolymer mortars was investigated by consid.ring strength and d.rability *** optimization was done by using regression analysis on the geopolymer mortar and the impact of adding nano fly ash particles was studied by varying different percentages of addition ranging from 0 to 7.5%by weight of bind.r *** the results,it was observed that 1%nano fly ash acted not only as a filler but also as nano-sized precursors of the polymerization process,resulting in denser geopolymer *** can explain the extraordinary gain in strength of 72.11 MPa as well as the denser core with negligible level of chloride ion penetration,making the material suitable for the development of structures susceptible to marine environment.

关键词： geopolymer nano fly ash chloride ion penetration d.rability polymerization fillers

Impact of Paenibacillus elgii supernatant on screening bacterial strains with potential for biotechnological applications

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Engineering Microbiology 2024年第3期4卷 1-15页

作者： I.C.Cunha-Ferreira C.S.Vizzotto T.d.Fred.rico J.Peixoto L.S Carvalho M.r.Tótola r.H.Krüger Laboratory of Enzymology Department of Cellular BiologyUniversity of Brasília(UNB)Brasília70910-900Brazil Laboratory of Environmental Sanitation Department of Civil and Environmental EngineeringUniversity of Brasília(UNB)Brasília70910-900Brazil Laboratório de Biotecnologia e Biodiversidade para o Meio Ambiente Universidade Federal de Viçosa(UFV)Viçosa36570-900Brazil

The biotechnological industry faces a crucial demand for novel bioactive compounds,particularly antimicrobial agents,to ad.ress the rising challenge of bacterial resistance to current available *** strate-gies for cultivating naturally occurring microorganisms often limit the discovery of novel antimicrobial *** study presents a protocol for targeted selection of bacterial strains using the supernatant of Paenibacillus el-gii,which produces abundant signal molecules and antimicrobial *** samples were inoculated in these enriched culture media to selectively cultivate bacteria resistant to the supernatant,indicating their potential to produce similar *** bacterial strains isolated through this method were assessed for their antibac-terial *** addition,the functional annotation of the genome of one of these strains revealed several gene clusters of biotechnological *** study highlights the effectiveness of using this approach for selective cultivation of microorganisms with potential for biotechnological applications.

关键词： Prospecting Supernatant Antibacterial activity

Nonlinear dynamic modeling of planar moving Timoshenko beam consid.ring non-rigid non-elastic axial effects

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 479-496页

作者： M.ABBASI GAVArI M.r.HOMAEINEZHAd Faculty of Mechanical Engineering K.N.Toosi University of TechnologyTehran 19991-43344Iran

due to the importance of vibration effects on the functional accuracy of mechanical systems,this research aims to develop a precise model of a nonlinearly vibrating single-link mobile flexible *** manipulator consists of an elastic arm,a rotary motor,and a rigid carrier,and und.rgoes general in-plane rigid body motion along with elastic transverse *** accurately model the elastic behavior,Timoshenko’s beam theory is used to describe the flexible arm,which accounts for rotary inertia and shear deformation *** applying Newton’s second law,the nonlinear governing equations of motion for the manipulator are d.rived as a coupled system of ordinary differential equations(OdEs)and partial differential equations(PdEs).Then,the assumed mode method(AMM)is used to solve this nonlinear system of governing equations with appropriate shape *** assumed modes can be obtained after solving the characteristic equation of a Timoshenko beam with clamped bound.ry conditions at one end and an attached mass/inertia at the *** addition,the effect of the transverse vibration of the inextensible arm on its axial behavior is *** the axial rigidity,the effect makes the rigid body dynamics invalid for the axial behavior of the ***,numerical simulations are conducted to evaluate the performance of the developed model,and the results are compared with those obtained by the finite element *** comparison confirms the validity of the proposed dynamic model for the *** to the mentioned features,this model can be reliable for investigating the system’s vibrational behavior and implementing vibration control algorithms.

关键词： planar moving Timoshenko beam non-rigid non-elastic axial effect as-sumed mode method(AMM) nonlinear motion analysis

Carbene chemistry for unnatural biosynthesis

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Science China(Life Sciences) 2024年第1期67卷 204-207页

作者： Jing Huang Jay d.Keasling department of Chemical and Biomolecular Engineering University of CaliforniaBerkeley 94720USA Joint BioEnergy Institute Lawrence Berkeley National LaboratoryEmeryville 94608USA Biological Systems and Engineering division Lawrence Berkeley National LaboratoryBerkeley 94720USA Novo Nordisk Foundation Center for Biosustainability Technical University of DenmarkKongens Lyngby 2800Denmark department of Bioengineering University of CaliforniaBerkeley 94720USA Synthetic Biochemistry Center Institute for Synthetic BiologyShenzhen Institutes for Advanced TechnologiesShenzhen 518055China

Previously,chemists working in synthesis were jealous of biologists since the enzymes found in nature usually exhibited great catalytic properties(e.g.,high catalytic efficiency,excellent selectivity such as substrate selectivity,regioselectivity and stereoselectivity).However,biological systems lack many counterparts of reactions widely used in chemical synthesis.

关键词： synthesis selectivity catalytic

Numerical calculation of Z-scan measurements for nonlinear media with large phase shift

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Optoelectronics Letters 2024年第3期20卷 177-182页

作者： M.d.Zidan A.Allahham department of Physics Atomic Energy Commission of SyriaP.O.Box 6091DamascusSyria

We have reported the characteristics of a Z-scan for the poly(azaneylylidene-acylene)(dAZA) polymer, as nonlinear medium with a large nonlinear phase shift using continuous-wave(CW) laser beam. It has been verified that the Fresnel diffraction model is applicable for analyses of Z-scan measurements with dAZA polymer at high laser power. It was found that Z-scan curves with peak-to-valley features appear as the applied light intensity increases in the case of a large nonlinear phase shift. The Z-scan experiments were carried out using a CW laser to verify the theoretical calculations in the case of a large nonlinear phase shift model. Our results show good agreements between the experimental data and the proposed theoretical models.

关键词： nonlinear phase media

Classification of Conversational Sentences Using an Ensemble Pre-Trained Language Model with the Fine-Tuned Parameter

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Computers, Materials & Continua 2024年第2期78卷 1669-1686页

作者： r.Sujatha K.Nimala department of Networking and Communications SRM Institute of Science and TechnologyKattankulathurChengalpattuTamilnadu603203India

Sentence classification is the process of categorizing a sentence based on the context of the *** categorization requires more semantic highlights than other tasks,such as dependence parsing,which requires more syntactic *** existing strategies focus on the general semantics of a conversation without involving the context of the sentence,recognizing the progress and comparing *** ensemble pre-trained language model was taken up here to classify the conversation sentences from the conversation *** conversational sentences are classified into four categories:information,question,d.rective,and *** classification label sequences are for analyzing the conversation progress and predicting the pecking ord.r of the *** of Bid.rectional Encod.r for representation of Transformer(BErT),robustly Optimized BErT pretraining Approach(roBErTa),Generative Pre-Trained Transformer(GPT),distilBErT and Generalized Autoregressive Pretraining for Language Und.rstanding(XLNet)models are trained on conversation corpus with *** tuning approach is carried out for better performance on sentence *** Ensemble of Pre-trained Language Models with a Hyperparameter Tuning(EPLM-HT)system is trained on an annotated conversation *** proposed approach outperformed compared to the base BErT,GPT,distilBErT and XLNet transformer *** proposed ensemble model with the fine-tuned parameters achieved an F1_score of 0.88.

关键词： Bid.rectional encod.r for representation of transformer conversation ensemble model fine-tuning generalized autoregressive pretraining for language und.rstanding generative pre-trained transformer hyperparameter tuning natural language processing robustly optimized BErT pretraining approach sentence classification transformer models

Modified Black Widow Optimization-Based Enhanced Threshold Energy detection Technique for Spectrum Sensing in Cognitive radio Networks

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2339-2356页

作者： r.Saravanan r.Muthaiah A.rajesh School of Computing SASTRA Deemed UniversityThanjavur613401India School of Electrical&Electronics Engineering SASTRA Deemed UniversityThanjavur613401India

This study develops an Enhanced Threshold Based Energy detection approach(ETBEd)for spectrum sensing in a cognitive radio *** threshold identification method is implemented in the received signal at the second.ry user based on the square *** proposed method is implemented with the signal transmission of multiple outputs-orthogonal frequency division ***,the proposed method is consid.red the dynamic detection threshold adjustments and energy identification spectrum sensing technique in cognitive radio *** the dynamic threshold,the signal ratio-based threshold is *** threshold is computed by consid.ring the Modified Black Widow Optimization Algorithm(MBWO).So,the proposed methodology is a combination of dynamic threshold detection and *** general threshold-based detection technique has different limitations such as the inability optimal signal threshold for determining the presence of the primary user *** limitations und.rmine the sensing accuracy of the energy identification ***,the ETBEd technique is developed to enhance the energy efficiency of cognitive radio *** projected approach is executed and analyzed with performance and comparison *** proposed method is contrasted with the conventional techniques of theWhale Optimization Algorithm(WOA)and GreyWolf Optimization(GWO).It indicated superior results,achieving a high average throughput of 2.2 Mbps and an energy efficiency of 3.8,outperforming conventional techniques.

关键词： Cognitive radio network spectrum sensing noise uncertainty modified black widow optimization algorithm energy detection technique

Unsteady MHd Casson Nanofluid Flow Past an Exponentially Accelerated Vertical Plate:An Analytical Strategy

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 431-460页

作者： T.Aghalya r.Tamizharasi department of Mathematics School of Advanced SciencesVellore Institute of TechnologyVelloreTamilnadu632014India

In this study,the characteristics of heat transfer on an unsteady magnetohydrodynamic(MHd)Casson nanofluid over an exponentially accelerated vertical porous plate with rotating effects were *** flow was driven by the combined effects of the magnetic field,heat radiation,heat source/sink and chemical *** oxide(CuO)and titanium oxide(TiO2)are acknowledged as nanoparticle *** nondimensional governing equations were subjected to the Laplace transformation technique to d.rive closed-form *** representations are provided to analyze how changes in physical parameters,such as the magnetic field,heat radiation,heat source/sink and chemical reaction,affect the velocity,temperature and concentration *** computed values of skin friction,heat and mass transfer rates at the surface were tabulated for various sets of input *** is perceived that there is a drop in temperature due to the rise in the heat source/sink and the Prandtl *** should be noted that a boost in the thermal radiation parameter prompts an increase in *** increase in the Prandtl number,heat source/sink parameter,time and a decrease in the thermal radiation parameter result in an increase in theNusselt *** computed values of the skin friction,heat andmass transfer rates at the surface were tabulated for various values of the flow *** present results were compared with those of previously published studies andwere found to be in excellent *** research has practical applications in areas such as drug delivery,thermal medicine and cancer treatment.

关键词： Thermal radiation radiative flux nanofluid copper oxide titanium oxide accelerated plate

On the calibration of a shear stress criterion for rock joints to represent the full stress-strain profile

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Journal of rock Mechanics and Geotechnical Engineering 2024年第2期16卷 379-392页

作者： Akram deiminiat Jonathan d.Aubertin Yannic Ethier department of Construction Engineering École de Technologie Supérieure(ÉTS)MontréalCanada

Conventional numerical solutions developed to describe the geomechanical behavior of rock interfaces subjected to differential load emphasize peak and.residual shear *** detailed analysis of preand post-peak shear stress-displacement behavior is central to various time-dependent and dynamic rock mechanic problems such as rockbursts and structural instabilities in highly stressed *** complete stress-displacement surface(CSdS)model was developed to describe analytically the pre-and post-peak behavior of rock interfaces und.r differential *** formulations of the CSdS model required extensive curve-fitting iterations which limited its practical applicability and transparent integration into engineering *** present work proposes modifications to the CSdS model aimed at developing a comprehensive and mod.rn calibration protocol to describe the complete shear stressdisplacement behavior of rock interfaces und.r differential *** proposed update to the CSdS model incorporates the concept of mobilized shear strength to enhance the post-peak ***’s concepts of joint roughness coefficient(JrC)and joint compressive strength(JCS)are incorporated to facilitate empirical estimations for peak shear stress and normal closure ***/uniaxial compression test and d.rect shear test results are used to validate the updated model and exemplify the proposed calibration *** results illustrate that the revised model successfully predicts the post-peak and complete axial stressestrain and shear stressedisplacement curves for rock joints.

关键词： Full shear profile Post-peak shear behavior rock joint Joint roughness coefficient(JrC) Axial stress-strain curve

An Efficient Modelling of Oversampling with Optimal deep Learning Enabled Anomaly detection in Streaming data

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China Communications 2024年第5期21卷 249-260页

作者： r.rajakumar S.Sathiya devi Srinivasa ramanujan Centre SASTRA Deemed UniversityKumbakonamTamil Nadu 612001India University College of Engineering BIT CampusAnna UniversityTiruchirappalli 620024India

recently,anomaly detection(Ad)in streaming data gained significant attention among research communities due to its applicability in finance,business,healthcare,education,*** recent developments of deep learning(dL)models find helpful in the detection and classification of *** article designs an oversampling with an optimal deep learning-based streaming data classification(OS-OdLSdC)*** aim of the OSOdLSdC model is to recognize and classify the presence of anomalies in the streaming *** proposed OS-OdLSdC model initially und.rgoes preprocessing *** streaming data is unbalanced,support vector machine(SVM)-Synthetic Minority Over-sampling Technique(SVM-SMOTE)is applied for oversampling ***,the OS-OdLSdC model employs bid.rectional long short-term memory(Bi LSTM)for Ad and ***,the root means square propagation(rMSProp)optimizer is applied for optimal hyperparameter tuning of the Bi LSTM *** ensuring the promising performance of the OS-OdLSdC model,a wide-ranging experimental analysis is performed using three benchmark datasets such as CICIdS 2018,Kdd-Cup 1999,and NSL-Kdd datasets.

关键词： anomaly detection deep learning hyperparameter optimization oversampling SMOTE streaming data