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Nonlinear wave dispersion in monoatomic chains with lumped and distributed masses:discrete and continuum models

Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 633-648页

作者： E.GHAVANLOO s.EL-BORGI school of Mechanical Engineering Shiraz UniversityShiraz 71963-16548Iran Mechanical Engineering Program Texas A&M University at QatarDoha 23874Qatar

The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed *** developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a *** inclusions are idealized by lumped masses,and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed ***,the model is capable of depicting the wave propagation in bi-material bars,wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed *** discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered,and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method(LPM).Next,a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization *** subsequent use of the second-order method of multiple scales(MMs)facilitates the derivation of the corresponding nonlinear dispersion relation in a closed *** novelties of the present study consist of(i)considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains;(ii)developing the second-order LPM for the wave propagation in the discrete chains;and(iii)deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed ***,a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum *** parameters include the ratio of the spring mass to the lumped mass,the nonlinear stiffness coefficient of the spring,and the wave amplitude.

关键词： nonlinear mass-spring chain discrete model continuum model LindstedtPoincare method(LPM) method of multiple scales(MMs) dispersion phase velocity

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Enhanced entropy generation and heat transfer characteristics of magnetic nano-encapsulated phase change materials in latent heat thermal energy storage systems

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1051-1070页

作者： P.s.REDDY P.sREEDEVI Department of Mathematics Rajeev Gandhi Memorial College of Engineering and TechnologyNandyal 518501India

The objective of the current study is to investigate the importance of entropy generation and thermal radiation on the patterns of velocity,isentropic lines,and temperature contours within a thermal energy storage device filled with magnetic nanoencapsulated phase change materials(NEPcMs).The versatile finite element method(FEM)is implemented to numerically solve the governing *** effects of various parameters,including the viscosity parameter,ranging from 1 to 3,the thermal conductivity parameter,ranging from 1 to 3,the Rayleigh parameter,ranging from 102 to 3×10^(2),the radiation number,ranging from 0.1 to 0.5,the fusion temperature,ranging from 1.0 to 1.2,the volume fraction of NEPcMs,ranging from 2%to 6%,the stefan number,ranging from 1 to 5,the magnetic number,ranging from 0.1 to 0.5,and the irreversibility parameter,ranging from 0.1 to 0.5,are examined in detail on the temperature contours,isentropic lines,heat capacity ratio,and velocity ***,the heat transfer rates at both the cold and hot walls are analyzed,and the findings are presented *** results indicate that the time taken by the NEPcMs to transition from solid to liquid is prolonged inside the chamber region as the fusion temperatureθf ***,the contours of the heat capacity ratio cr decrease with the increase in the stefan number ste.

关键词： volume fraction of nano-encapsulated phase change material(NEPcM) radiation stefan number heat capacity ratio entropy generation

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Engineering of efficient visible light photocatalysts:Ti_(1-x+y)cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： s.M.Yakout A.M.Youssef Inorganic chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount *** the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)cu_(0.03)O_(2), Ti_(0.965)cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)cu_(0.03)O_(2)powders while Ti_(0.965)cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus cu^(2+)ions. Ti_(0.965)cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on sEM images, incorporation of cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)cu_(0.03)O_(2), Ti_(0.965)cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm cR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm cR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm MB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher ch

关键词： semiconductor TiO_(2) Rare earths congo red Methylene blue solar spectrum Photodegradation

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Enhanced saturation magnetization in La^(3+) doped Nico ferrites prepared by sol-gel auto-combustion method

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Journal of Rare Earths 2024年第8期42卷 1546-1554,I0005页

作者： Maddileti Jelli Vidyasagar Thopudurthy Krishna Reddy c.V. Department of Physics Rayalaseema UniversityKurnoolA.P518007.Iindia Department of Physics Govermment PolytechnicRayachotiA.P516269India

Lanthanum doped nickel-cobalt nano ferrites with chemical formula Ni_(0.5)co_(0.5)LaxFe_(2-x)O_(4)(x=0.05,0,10,0.15 and 0,20) were prepared using a simple sol-gel auto combustion *** basic structural properties were determined by X-ray diffraction method and the formation of single phased spinel ferrite was *** crystalline size decreased from 25 to 11 nm and lattice parameter a increases with increase of La *** surface morphology of these ferrites was observed by field-emission scanning electron microscopy(FEsEM) and agglomerated irregular grains are observed with increase of the rare earth element La ***-dispersive X-ray spectroscopy(EDX) result confirms the presence of the required *** Fourier transform infrared spectroscopy(FTIR) spectrum indicates the formation of the spinel ferrite structure with M-O *** direct band measurements from ultraviolet-visible spectroscopy(UV-Vis) spectroscopy indicate that the direct band gap decreases from 1.39 to 1.19 eV for x=0.05 to x=0.15,then increases to 1.28 eV for x=*** room temperature magnetic properties of these ferrites were studied by a vibrating sample magnetometer(VsM).The enhanced saturation magnetization of 49.73 emu/g is observed for x=0.10 and then saturation magnetizations are gradually decreased for x=0.15 and x=*** the remanent magnetization and coercivity also follow the same trend.

关键词： Ferrites sol-gel auto combustion La doping Magnetic properties Rare earths

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The value of the INFEcTIONs scoring system in identifying bacterial infections among patients presenting at the emergency department of a middle-income country:A pilot study

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chinese Journal of Traumatology 2024年第2期27卷 77-82页

作者： Dooshanveer c.Nuckchady Department of Internal Medicine Victoria HospitalCandosMauritius

Purpose:To investigate which scoring system is the most accurate tool in predicting mortality among the infected patients who present to the emergency department in a middle-income country,and to validate a new scoring system to predict bacterial ***:This was a retrospective,single-center study among patients who were admitted via the emergency department of a public *** patients who were started on antibiotics were included in the study,while patients ageds were *** collected includeding patients'demographics,vital signs and basic laboratory parameters like white blood cell count and *** sensitivity and specificity of different scoring systems were calculated as well as their negative and positive predictive *** regression was used to derive a novel early warning system for bacterial *** area under the receiver operating characteristic(AUROc)was computed for each scoring ***:In total,109 patients were included in this *** quick sequential organ failure assessment(qsOFA),search out severity and rapid acute physiology score had the highest AUROc(≥0.89)for predicting mortality,while qsOFA and universal vital assessment were the simplest scoring systems with an AUROc>0.85;however,these scoring systems failed to predict whether patients were truly *** INFEcTIONs(short for impaired mental status,not conscious,fast heart rate,elevated creatinine,high temperature,on inotrope,low oxygen,high neutrophils and high sugar)model reached an AUROc of 0.88 to more accurately predict the infectious state of a ***:Middle-income countries should use the qsOFA or universal vital assessment score to identify the sickest patients in emergency *** INFEcTIONs score may help recognize patients with bacterial infections,but it should be further validated in multiple countries prior to widely use.

关键词： Prognosis Mortality Bacterial infection INFEcTIONs scoring system sequential organ failure assessment Prediction

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Isochrone Fitting of Galactic Globular clusters—Ⅵ.High-latitude clusters NGc 5024 (M53),NGc 5053,NGc 5272 (M3),NGc 5466,and NGc7099 (M30)

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Research in Astronomy and Astrophysics 2024年第6期24卷 170-190页

作者： G.A.Gontcharov s.s.savchenko A.A.Marchuk c.J.Bonatto O.s.Ryutina M.Yu.Khovritchev V.B.Il'in A.V.Mosenkov D.M.Poliakov A.A.smirnov central(Pulkovo)Astronomical Observatory Russian Academy of SciencesPulkovskoye chaussee 65/1St.Petersburg 196140Russia saint Petersburg state University Universitetskij pr.28St.Petersburg 198504Russia special Astrophysical Observatory Russian Academy of Sciences369167 Nizhnij ArkhyzRussia Departamento de Astronomia Instituto de FísicaUFRGSAv.Bento Gonçalves9500Porto AlegreRSBrazil saint Petersburg University of Aerospace Instrumentation Bol.Morskaya ul.67ASt.Petersburg 190000Russia Department of Physics and Astronomy Brigham Young UniversityN283 ESCProvoUT 84602USA

We fit various color–magnitude diagrams(cMDs) of the high-latitude Galactic globular clusters NGc 5024(M53),NGc 5053,NGc 5272(M3),NGc 5466,and NGc 7099(M30) by isochrones from the Dartmouth stellar Evolution Database and Bag of stellar Tracks and Isochrones for α–enrichment [α/Fe] = +*** the cMDs,we use data sets from Hubble space Telescope,Gaia,and other sources utilizing,at least,25 photometric filters for each *** obtain the following characteristics with their statistical uncertainties for NGc 5024,NGc 5053,NGc 5272,NGc 5466,and NGc 7099,respectively:metallicities [Fe/H] =-1.93 ± 0.02,-2.08 ± 0.03,-1.60 ± 0.02,-1.95 ± 0.02,and-2.07 ± 0.04 dex with their systematic uncertainty 0.1 dex;ages 13.00 ± 0.11,12.70 ± 0.11,11.63 ± 0.07,12.15 ± 0.11,and 12.80 ± 0.17 Gyr with their systematic uncertainty 0.8 Gyr;distances(systematic uncertainty added) 18.22 ± 0.06 ± 0.60,16.99 ± 0.06 ± 0.56,10.08 ± 0.04 ± 0.33,15.59 ±0.03 ± 0.51,and 8.29 ± 0.03 ± 0.27 kpc;reddenings E(B-V) = 0.023 ± 0.004,0.017 ± 0.004,0.023 ± 0.004,0.023 ± 0.003,and 0.045 ± 0.002 mag with their systematic uncertainty 0.01 mag;extinctions AV= 0.08 ± 0.01,0.06 ± 0.01,0.08 ± 0.01,0.08 ± 0.01,and 0.16 ± 0.01 mag with their systematic uncertainty 0.03 mag,which suggest the total Galactic extinction AV= 0.08 across the whole Galactic dust to extragalactic objects at the North Galactic *** horizontal branch morphology difference of these clusters is explained by their different metallicity,age,mass-loss efficiency,and loss of low-mass members in the evolution of the core-collapse cluster NGc 7099 and loose clusters NGc 5053 and NGc 5466.

关键词： (stars:)Hertzsprung Russell and c-M diagrams (IsM:)dust extinction (Galaxy:)globular clusters:general (Galaxy:)globular clusters:individual(NGc 5024,NGc 5053,NGc 5272,NGc 5466,NGc7099)

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Decomposition solutions and Bäcklund transformations of the B-type and c-type Kadomtsev-Petviashvili equations

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communications in Theoretical Physics 2024年第6期76卷 34-44页

作者： Xiazhi Hao s Y Lou college of science Zhejiang University of TechnologyHangzhou 310014China school of Physical science and Technology Ningbo UniversityNingbo 315211China

This paper introduces a modified formal variable separation approach,showcasing a systematic and notably straightforward methodology for analyzing the B-type Kadomtsev-Petviashvili(BKP)*** the application of this approach,we successfully ascertain decomposition solutions,Bäcklund transformations,the Lax pair,and the linear superposition solution associated with the aforementioned ***,we expand the utilization of this technique to the c-type Kadomtsev-Petviashvili(cKP)equation,leading to the derivation of decomposition solutions,Bäcklund transformations,and the Lax pair specific to this *** results obtained not only underscore the efficacy of the proposed approach,but also highlight its potential in offering a profound comprehension of integrable behaviors in nonlinear ***,this approach demonstrates an efficient framework for establishing interrelations between diverse systems.

关键词： decomposition solution Backlund transformation Lax pair linear superposition solution

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Quantized autoencoder(QAE)intrusion detection system for anomaly detection in resource-constrained loT devices using RT-loT2022 dataset

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cybersecurity 2024年第2期7卷 13-27页

作者： B s sharmila Rohini Nagapadma Depatment of Electronics and communication Engineering The National Institute of EngineeringMysoreKarnataka 570008India

In recent years,many researchers focused on unsupervised learning for network anomaly detection in edge devices to identify *** deployment of the unsupervised autoencoder model is computationally expensive in resource-constrained edge *** study proposes quantized autoencoder(QAE)model for intrusion detection systems to detect *** is an optimization model derived from autoencoders that incorporate pruning,clustering,and integer quantization *** autoencoder uint8(QAE-u8)and quantized autoencoder float16(QAE-f16)are two variants of QAE built to deploy computationally expensive Al models into Edge ***,we have generated a Real-Time Internet of Things 2022 dataset for normal and attack *** autoencoder model operates on normal traffic during the training *** same model is then used to reconstruct anomaly traffic under the assumption that the reconstruction error(RE)of the anomaly will be high,which helps to identify the ***,we study the performance of the autoencoders,QAE-u8,and QAE-f16 using accuracy,precision,recall,and F1 score through an extensive experimental *** showed that QAE-u8 outperforms all other models with a reduction of 70.01%in average memory utilization,92.23%in memory size compression,and 27.94%in peak cPU ***,the proposed QAE-u8 model is more suitable for deployment on resource-constrained IoT edge devices.

关键词： IoT constrained system

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A study on the Explainability of Thyroid cancer Prediction:sHAP Values and Association-Rule Based Feature Integration Framework

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computers, Materials & continua 2024年第5期79卷 3111-3138页

作者： sujithra sankar s.sathyalakshmi Department of computer Applications Hindustan Institute of Technology and ScienceChennaiTamil NaduIndia Department of computer Engineering Hindustan Institute of Technology and ScienceChennaiTamil NaduIndia

In the era of advanced machine learning techniques,the development of accurate predictive models for complex medical conditions,such as thyroid cancer,has shown remarkable *** predictivemodels for thyroid cancer enhance early detection,improve resource allocation,and reduce ***,the widespread adoption of these models in clinical practice demands predictive performance along with interpretability and *** paper proposes a novel association-rule based feature-integratedmachine learning model which shows better classification and prediction accuracy than present *** study also focuses on the application of sHapley Additive exPlanations(sHAP)values as a powerful tool for explaining thyroid cancer prediction *** the proposed method,the association-rule based feature integration framework identifies frequently occurring attribute combinations in the *** original dataset is used in trainingmachine learning models,and further used in generating sHAP values *** the next phase,the dataset is integrated with the dominant feature sets identified through association-rule based *** new integrated dataset is used in re-training the machine learning *** new sHAP values generated from these models help in validating the contributions of feature sets in predicting *** conventional machine learning models lack interpretability,which can hinder their integration into clinical decision-making *** this study,the sHAP values are introduced along with association-rule based feature integration as a comprehensive framework for understanding the contributions of feature sets inmodelling the *** study discusses the importance of reliable predictive models for early diagnosis of thyroid cancer,and a validation framework of *** proposed model shows an accuracy of 93.48%.Performance metrics such as precision,recall,F1-score,and the area un

关键词： Explainable AI machine learning clinical decision support systems thyroid cancer association-rule based framework sHAP values classification and prediction

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correlation composition Awareness Model with Pair collaborative Localization for IoT Authentication and Localization

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computers, Materials & continua 2024年第4期79卷 943-961页

作者： Kranthi Alluri s.Gopikrishnan school of computer science and Engineering VIT-AP UniversityAmaravathiAndhra Pradesh522241India

secure authentication and accurate localization among Internet of Things(IoT)sensors are pivotal for the functionality and integrity of IoT *** authentication and localization are intricate and symbiotic,impacting both the security and operational functionality of IoT ***,accurate localization and lightweight authentication on resource-constrained IoT devices pose several *** overcome these challenges,recent approaches have used encryption techniques with well-known key ***,these methods are inefficient due to the increasing number of data breaches in their localization *** proposed research efficiently integrates authentication and localization processes in such a way that they complement each other without compromising on security or *** proposed framework aims to detect active attacks within IoT networks,precisely localize malicious IoT devices participating in these attacks,and establish dynamic implicit authentication *** integrated framework proposes a correlation composition Awareness(ccA)model,which explores innovative approaches to device correlations,enhancing the accuracy of attack detection and ***,this framework introduces the Pair collaborative Localization(PcL)technique,facilitating precise identification of the exact locations of malicious IoT *** address device authentication,a Behavior and Performance Measurement(BPM)scheme is developed,ensuring that only trusted devices gain access to the *** work has been evaluated across various environments and compared against existing *** results prove that the proposed methodology attains 96%attack detection accuracy,84%localization accuracy,and 98%device authentication accuracy.

关键词： sensor localization IoT authentication network security data accuracy precise location access control security framework

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