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SIRS epidemic modeling using fractional-ordered differential equations:Role of fear effect

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International Journal of Biomathematics 2024年第5期17卷 79-100页

作者： Shiv Mangal O.p.Misra Joydip Dhar School of Mathematics and Allied Sciences Jiwaji University GwaliorMadhya PradeshIndia Department of Mathematics Post Graduate College BinaMadhya PradeshIndia Department of Applied Sciences Atal Bihari Vajpayee-Indian Institute of Information Technology and Management GwaliorMadhya PradeshIndia

In this paper,an SIRS epidemic model using Grunwald-Letnikov fractional-order derivative is formulated with the help of a nonlinear system of fractional differential equations to analyze the effects of fear in the population during the outbreak of deadly infectious *** criteria for the spread or extinction of the disease are derived and discussed on the basis of the basic reproduction *** condition for the existence of Hopf bifurcation is discussed considering fractional order as a bifurcation ***,using the Grunwald-Letnikov approximation,the simulation is carried out to confirm the validity of analytic results *** the real data of COVID-19 in India recorded during the second wave from 15 May 2021 to 15 December 2021,we estimate the model parameters and find that the fractional-order model gives the closer forecast of the disease than the classical *** the analytical results and numerical simulations presented in this study suggest different policies for controlling or eradicating many infectious diseases.

关键词： SIRS epidemic model fear effect Mittag-Leffler function Hopf bifurcation parameter estimation

performance and combustion study of a low heat rejection engine running with biogas–diethyl ether–diesel

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Waste Disposal and Sustainable Energy 2024年第1期6卷 151-162页

作者： Sanjaya K.Mishra premananda pradhan Shakti p.Jena Department of Mechanical Engineering S‘O’A Deemed to be UniversityBhubaneswar751030India

The present research focuses on addressing the faster depletion of fossil fuels and environmental pollution in addition to the energy crisis that hinders the progress of a *** the current research,waste banana leaves were considered as substrates for biogas *** is taken as the primary fuel in dual fuel(Df)operations to maximize possible diesel *** performance and combustion assessment were executed in a low heat rejection(LHR)engine using 5%diethyl ether by volume blended with diesel(5DEE)as pilot *** combustion attributes of the engine reveal that the apex of net heat release rate(NHRR)curve retarded a bit as compared to apex of base *** peak cylinder pressure was noted to be 6.19 Mpa in the LHR engine running with 5DEE+biogas at 11.7°crank angle(CA)after top dead center(aTDC)compared to 5.23 Mpa for the diesel alone operation at the same *** apex point for NHRR was observed to be 54.51 J(°)^(−1)for 5DEE+biogas in LHR engine positioned at 3.2°*** brake thermal efficiency at full engine load operation decreased by 12.7%and 5.2%for biogas substitutions of 0.8 kg h^(−1)with diesel and 5DEE,respectively,compared to the base *** smoke opacity and nitric oxide emissions were reduced during the Df run accompanied by diethyl ether as a fuel additive.

关键词： Biogas Banana leaves Coating Diesel engine Diethyl ether Exhaust emissions

Developing a two-decadal time-record of rice field maps using Landsat-derived multi-index image collections with a random forest classifier:A Google Earth Engine based approach

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Information processing in Agriculture 2024年第2期11卷 260-275页

作者： W.Ashane M.fernando I.p.Senanayake Department of Nano Science Technology Wayamba University of Sri LankaKuliyapitiya 60200Sri Lanka Dchoolf Engineing CllegeoEngineeringSience and EnionmentThe UniversyewcastleCallaghanW2Austraia

Historic maps showing the temporal distribution of rice fields are important for precision agriculture,irrigation optimisation,forecasting crop yields,land use management and formulating ***,mapping rice felds using traditional ground surveys is impractical when high cost,time and labour requirements are considered,and the availability of such detailed records is *** satellite remote sensing appears to be a viable solution,conventional segmentation and classification methods with spectral bands are often unable to contrast the distinct characteristics between rice fields and other vegetation *** this end,we explored a novel,Google Earth Engine(GEE)based multiindex random forest(Rf)classification approach to map rice fields over two *** images from 2000 to 2020 of two Sri Lankan rice cultivation districts were extracted from GEE and a multi-index Rf classification algorithm was applied to distinguish the rice *** results showed above 80%accuracy for both training and validation,when compared against high spatial resolution Google Earth *** essence,multi-index sampling and Rf together synergised the compelling classifcation accuracy by effectively capturing vegetation,water(ponding)and soil characteristics unique to the rice felds using a single-click *** maps developed in this study were further compared against the MODIS land cover type product(MCD12Q1)and the corresponding superior statistics on rice fields demonstrated the robustness of the proposed *** work seeking effective index combinations is recommended,and this approach can potentially be extended to other crop analyses elsewhere.

关键词： Google Earth Engine(GEE) Image classification Random forest Mapping rice fields Time series analysis Vegetation index

Temperature-dependent thermal conductivity and fuel performance of UN-UO_(2) and UN-X-UO_(2)(X=Mo,W)composite nuclear fuels by finite element modeling

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Journal of Materiomics 2024年第4期10卷 937-946页

作者： faris Sweidan Diogo Ribeiro Costa Huan Liu pär Olsson KTH Royal Institute of Technology Nuclear EngineeringStockholm10691Sweden Westinghouse Electric Sweden AB Västerås72163Sweden

The temperature-dependent effective thermal conductivity of UN-X-UO_(2)(X=Mo,W)nuclear fuel composite was *** the experimental design,the thermal conductivity was calculated using finite Element Modeling(feM),and compared with analytical models for 10%,30%,50%,and 70%(in mass)uncoated/coated UN microspheres in a UO2 *** feM results show an increase in the fuel thermal conductivity as the mass fraction of the UN microspheres increases from 1.2 to 4.6 times the UO2 reference at 2,000 *** results from analytical models agree with the thermal conductivity estimated by *** results also show that Mo and W coatings have similar thermal behaviors,and the coating thickness influences the thermal conductivity of the *** higher weight fractions,the thermal conductivity of the fuel composite at room temperature is substantially influenced by the high thermal conductivity coatings approaching that of ***,the thermal conductivity from feM was used in the fuel thermal performance evaluation during LWR normal operation to calculate the maximum centerline *** results show a significant decrease in the fuel maximum centerline temperature ranging from−94 K for 10% UN to−414 K for 70%(in mass)UN compared to UO2 under the same operating conditions.

关键词： Accident tolerant fuel UN-X-UO_(2) Composite nuclear fuel Thermal conductivity finite element modeling Thermal performance

Modelling the brittle rock failure by the quaternion-based bonded-particle model in DEM

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Rock Mechanics Bulletin

Rock Mechanics Bulletin 2024年第2期3卷 87-95页

作者： Tao Zhao philip E.f.Collins Department of Civil and Environmental Engineering Brunel University LondonLondonUB83PHUnited Kingdom

This paper presents an investigation of brittle rock failure by the quaternion-based bonded-particle model in discrete element method(DEM).Unlike traditional approaches that utilize Euler angles or rotation matrices,this model employs unit quaternions to represent the spatial rotations of *** method simplifies the rep-resentation of 3D rotations,providing a more intuitive framework for modelling complex interactions in granular *** numerical model was validated by the uniaxial compression tests on rock,with good agreement with well-documented experimental data in terms of the rock uniaxial compression strength(UCS)and failure *** loading,the rock sample demonstrated a linear-elastic response at an axial strain of smaller than 0.45%.However,as internal bond breakage accumulated,this linear relationship weakened,and the stress-strain curve began to deviate from its initial linear *** bond breakage and the overall deformation of the rock were primarily controlled by the shear bonding *** UCS was achieved at an axial strain of 0.625%,at which point the internal shear bonding force chains were predominantly aligned *** brittle failure occurred when the internal damage of solids nucleated to form an interconnected failure plane,accompanied by a sharp rise in the internal damage *** area of failure plane increased with the loading strain rate,gradually transforming the failure pattern from the local damage to a complete fragmentation.

关键词： Brittle failure Quaternion DEM bonded model Uniaxial compression test Rate dependent Internal damage

Mathematical modeling and simulations of stress mitigation by coating polycrystalline particles in lithium-ion batteries

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 947-962页

作者： N.IQBAL J.CHOI S.f.SHAH C.LEE S.LEE Department of Mechanical Roboticsand Energy EngineeringDongguk University-SeoulSeoul 04620Republic of Korea

A chemo-mechanical model is developed to investigate the effects on the stress development of the coating of polycrystalline Ni-rich LiNixMnyCo_(z)O_(2)(x≥0.8)(NMC)particles with poly(3,4-ethylenedioxythiophene)(pEDOT).The simulation results show that the coating of primary NMC particles significantly reduces the stress generation by efficiently accommodating the volume change associated with the lithium diffusion,and the coating layer plays roles both as a cushion against the volume change and a channel for the lithium transport,promoting the lithium distribution across the secondary particles more ***,the lower stiffness,higher ionic conductivity,and larger thickness of the coating layer improve the stress *** paper provides a mathematical framework for calculating the chemo-mechanical responses of anisotropic electrode materials and fundamental insights into how the coating of NMC active particles mitigates stress levels.

关键词： lithium-ion battery(LIB) polycrystalline particle coating finite element simulation Ni-rich LiNixMnyCo_(z)O_(2)(x>0.8)(NMC)

Threshold-Based Software-Defined Networking(SDN)Solution for Healthcare Systems against Intrusion Attacks

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1469-1483页

作者： Laila M.Halman Mohammed J.f.Alenazi Department of Computer Engineering College of Computer ScienceKing Saud UniversityRiyadh11451Saudi Arabia

The healthcare sector holds valuable and sensitive *** amount of this data and the need to handle,exchange,and protect it,has been increasing at a fast *** to their nature,software-defined networks(SDNs)are widely used in healthcare systems,as they ensure effective resource utilization,safety,great network management,and *** this sector,due to the value of thedata,SDNs faceamajor challengeposed byawide range of attacks,such as distributed denial of service(DDoS)and probe *** attacks reduce network performance,causing the degradation of different key performance indicators(KpIs)or,in the worst cases,a network failure which can threaten human *** can be significant,especially with the current expansion of portable healthcare that supports mobile and wireless devices for what is called mobile health,or *** this study,we examine the effectiveness of using SDNs for defense against DDoS,as well as their effects on different network KpIs under various *** propose a threshold-based DDoS classifier(TBDC)technique to classify DDoS attacks in healthcare SDNs,aiming to block traffic considered a hazard in the form of a DDoS *** then evaluate the accuracy and performance of the proposed TBDC *** technique shows outstanding performance,increasing the mean throughput by 190.3%,reducing the mean delay by 95%,and reducing packet loss by 99.7%relative to normal,with DDoS attack traffic.

关键词： Network resilience network management attack prediction software defined networking(SDN) distributed denial of service(DDoS) healthcare

Recent advancements in continuously scalable conversion-ratio switched-capacitor converter

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Journal of Semiconductors 2024年第4期45卷 8-11页

作者： Mo Huang Yuanfei Wang Rui p.Martins Yan Lu State Key Laboratory of Analog and Mixed-Signal VLSI Institute of MicroelectronicsUniversity of MacaoMacaoChina

Switched-capacitor(SC)DC-DC converter[1]is an impor-tant alternative to inductive DC-DC converter,in terms of removing the bulky power ***,it is widely used in low-profile,low-power applications,such as the internet of things(IoT)sensor nodes and energy harvesting[2].Mean-while,considering that capacitor has a much higher energy density than inductor,high-power applications.

关键词： converter switched removing

Are we close to using Alzheimer blood biomarkers in clinical practice?

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Neural Regeneration Research 2024年第12期19卷 2583-2585页

作者： Bruno p.Imbimbo Simone Lista Camillo Imbimbo Robert Nisticò Department of Research&Development Chiesi FarmaceuticiParmaItaly i+HeALTH Strategic Research Group Department of Health SciencesMiguel de Cervantes European University(UEMC)ValladolidSpain Department of Brain and Behavioral Sciences University of PaviaPaviaItaly School of pharmacy University of Rome“Tor Vergata”RomeItaly Laboratory of pharmacology of Synaptic plasticity EBRI Rita Levi-Montalcini FoundationRomeItaly

Alzheimer's disease(AD) is a progressive neurodegenerative disease histologically characterized by the presence of extraneuronal plaques,mainly formed by the 42-aminoacid isoform of amyloid-(Aβ_(1-42)),and by intraneuronal neurofibrillary to ngles,mainly formed by the tau protein and its hyperphosphorylated isoforms(p-tau).AD is the most common cause of dementia,with an estimated lifetime risk of about 1 in 10 for men and 1 in 5 for women.

关键词： Alzheimer tau Aβ