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Analysis of the oscillatory Flows of Multiple Shock Waves in a Constant Area Duct

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Journal of Thermal Science 2024年第3期33卷 794-806页

作者： k JAMES Jintu kIM Heuy Dong Department of Mechanical Engineering Andong National UniversityAndong36729Republic of Korea CAD-IT korea Co. Ltd.Seoul08591Republic of Korea

The oscillatory response of multiple shock waves to downstream perturbations in a supersonic flow is studied numerically in a rectangular *** shock waves are formed inside the duct at a shock Mach number of *** duct has an exit height of H,and the effect of duct resonance on multiple shock oscillations is investigated by attaching exit ducts of lengths 0H,50H,and *** downstream disturbance frequency varied from 10 Hz to 200 Hz to explore the oscillation characteristics of the multiple shock *** oscillatory response of shock waves under self-excited and forced oscillation conditions are analyzed in terms of wall static pressure,shock train leading-edge location,shock train length,and the size of the separation *** extent of the initial shock location increases with an increase in exit duct length for the self-excited oscillation *** analysis of the shock train leading edge and the spectral analysis of wall static pressure variations are *** variation in the shock train length is analyzed using the pressure ratio method for self-excited as well as forced *** RMS amplitude of the normalized shock train length(ζ_(ST))increases with an increase in the exit duct length for the self-excited oscillation *** the downstream perturbation frequency is increased,ζ_(ST)is decreased for exit duct *** all exit duct designs and downstream forcing frequencies,the size of the separation bubble grows and shrinks during the shock oscillations,demonstrating the dependence on duct resonance and forced oscillations.

关键词： shock train downstream disturbance supersonic flow shock wave boundary layer interaction duct resonance flow separation

Impact of Fin Arrangement on Heat Transfer and Melting Characteristics of Phase Change Material

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Journal of Thermal Science 2024年第2期33卷 435-456页

作者： Arun UNIYAL Yogesh k.PRAJAPATI Department of Mechanical Engineering National Institute of Technology UttarakhandSrinagar(Garhwal)246174India Department of Mechanical Engineering BIT SindriDhanbadJharkhand828123India

Present work investigates the heat transfer and melting behaviour of phase change material(PCM) in six enclosures(enclosure-1 to 6) filled with paraffin *** enclosures are equipped with distinct arrangements of the fins while keeping the fin's surface area equal in each *** analysis has been presented to recognize the suitable fin arrangements that facilitate improved heat transfer and melting rate of the *** wall of the enclosure is maintained isothermal for the temperature values 335 k,350 k and 365 *** length of the enclosure including fins is ranging between 0 and *** have been illustrated through the estimation of important performance parameters such as energy absorbing capacity,melting rate,enhancement ratio,and Nusselt *** has been found that melting time(to melt 100% of the PCM) is 60.5%less in enclosure-2(with two fins of equal length) as compared to the enclosure-1,having no *** the fin surface area equal,if the longer fin is placed below the shorter fin(enclosure-3),melting time is further decreased by 14.1% as compared to ***,among all the configurations,enclosure-6 with wire-mesh fin structure exhibits minimum melting time which is 68.4% less as compared to the *** on the findings,it may be concluded that fins are the main driving agent in the enclosure to transfer the heat from heated wall to the *** design and positioning of the fins improve the heat transfer rate followed by melting of the PCM in the entire area of the *** of the favourable vortices and natural convection current in the enclosure accelerate the melting phenomenon and help to reduce charging time.

关键词： phase change material enclosure fin melting fraction energy storage heat transfer

Radiative heat transfer analysis of a concave porous fin under the local thermal non-equilibrium condition:application of the clique polynomial method and physics-informed neural networks

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1613-1632页

作者： k.CHANDAN k.kARTHIk k.V.NAGARAJA B.C.PRASANNAkUMARA R.S.VARUN kUMAR T.MUHAMMAD Amrita School of Artificial Intelligence Amrita Vishwa VidyapeethamBengaluru 560035KarnatakaIndia Department of Studies in Mathematics Davangere UniversityDavangere 577002KarnatakaIndia Computational Science Lab Amrita School of EngineeringAmrita Vishwa VidyapeethamBengaluru 560035KarnatakaIndia Department of Pure and Applied Mathematics School of Mathematical SciencesSunway UniversityPetaling Jaya 47500Malaysia Department of Mathematics College of ScienceKing Khalid UniversityAbha 61413Saudi Arabia

The heat transfer through a concave permeable fin is analyzed by the local thermal non-equilibrium(LTNE)*** governing dimensional temperature equations for the solid and fluid phases of the porous extended surface are modeled,and then are nondimensionalized by suitable dimensionless ***,the obtained nondimensional equations are solved by the clique polynomial method(CPM).The effects of several dimensionless parameters on the fin's thermal profiles are shown by graphical ***,the current study implements deep neural structures to solve physics-governed coupled equations,and the best-suited hyperparameters are attained by comparison with various network *** results of the CPM and physicsinformed neural network(PINN)exhibit good agreement,signifying that both methods effectively solve the thermal modeling problem.

关键词： heat transfer fin porous fin local thermal non-equilibrium(LTNE)model physics-informed neural network(PINN)

Perceived value of microfinance and SME performance: The role of exploratory innovation

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International Journal of Innovation Studies 2024年第2期8卷 172-185页

作者： Christian Sarfo Jing A.Zhang Conor o'kane Paula o'kane Department of Management University of LincolnBrayford PoolLincoln LN67TSUnited Kingdom Department of Management Otago Business SchoolUniversity of OtagoPO Box 56Dunedin9054New Zealand

This study examines how perceived value of microfinance and exploratory innovation affect small and medium-sized enterprises(SME)performance in the context of a developing *** on the strategic innovation and microfinance literature,we hypothesize that(1)perceived value of microfinance affects exploratory innovation and SME performance,and(2)exploratory innovation serves as an effective mechanism through which microfinance enhances SME *** employ partial least squares structural equation modeling(PLS-SEM)to test our *** a sample of 581 Ghanaian SMEs with microfinance,the results of the PLS SEM support our *** further conducted a qualitative analysis of comments provided by the SMEs(n=144)to gain a deeper understanding of exploratory innovation in developing *** findings show that SMEs purposefully attempt to strengthen their exploratory inno-vation in *** discuss the theoretical and practical implications of these findings as well as future research avenues.

关键词： Perceived value of microfinance Exploratory innovation SME performance

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

Numerical Simulation of Thermocapillary Convection with Evaporation Induced by Boundary Heating

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Fluid Dynamics & Materials Processing 2024年第7期20卷 1667-1686页

作者： o.N.Goncharova V.B.Bekezhanova Altai State University Institute of Mathematics and Information TechnologiesBarnaul656049Russia Institute of Computational Modelling SB RAS Department of Differential Equations of MechanicsKrasnoyarsk660036Russia

The dynamics of a bilayer system filling a rectangular cuvette subjected to external heating is *** influence of two types of thermal exposure on the flow pattern and on the dynamic contact angle is *** particular,the cases of local heating from below and distributed thermal load from the lateral walls are *** simulation is carried out within the frame of a two-sided evaporative convection model based on the Boussinesq approximation.A benzine–air system is considered as reference *** variation in time of the contact angle is described for both heating *** lateral heating,near-wall boundary layers emerge together with strong convection,whereas the local thermal load from the lower wall results in the formation of multicellular motion in the entire volume of the fluids and the appearance of transition regimes followed by a steady-state *** results of the present study can aid the design of equipment for thermal coating or drying and the development of methods for the formation of patterns with required structure and morphology.

关键词： Thermocapillary convection two-phase system numerical modeling contact angle

Alkali and Plasma-Treated Guadua angustifolia Bamboo Fibers:A Study on Reinforcement Potential for Polymeric Matrices

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Journal of Renewable Materials 2024年第8期12卷 1399-1416页

作者： Patricia Luna Juan Lizarazo-Marriaga Alvaro Mariño Facultad de Ingeniería Universidad Nacional de ColombiaBogotá11001Colombia Facultad de Ciencias Universidad Nacional de ColombiaBogotá11001Colombia

This study focuses on treating Guadua angustifolia bamboo fibers to enhance their properties for reinforcement applications in composite ***(alkali)and physical(dry etching plasma)treatments were used separately to augment compatibility of Guadua angustifolia fibers with various composite *** influence of these treatments on the fibers’performance,chemical composition,and surface morphology were *** analysis indicated that alkali treatments reduced the tensile modulus of elasticity and strength of fibers by up to 40%and 20%,respectively,whereas plasma treatments maintain the fibers’mechanical *** spectroscopy revealed significant alterations in chemical composition due to alkali treatments,while plasma-treated fibers showed minimal *** examination through Scanning Electron Microscopy(SEM)revealed post-treatment modifications in both cases;alkali treatments served as a cleanser,eliminating lignin and hemicellulose from the fiber surface,whereas plasma treatments also produce rough *** results validate the impact of the treatments on the fiber mechanical performance,which opens up possibilities for using Guadua angustifolia fibers as an alternative reinforcement in composite manufacturing.

关键词： Bamboo fibers Guadua angustifolia alkali treatment dry etching plasma treatment composite reinforcement

Efficacy of acupuncture on cancer pain:A systematic review and meta-analysis

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Journal of Integrative Medicine 2024年第3期22卷 235-244页

作者： Miguel Faria Mónica Teixeira Maria João Pinto Paulo Sargento Núcleo de Investigação em Ciências e Tecnologias da Saúde Instituto Politécnico da Lusofonia1950-396 LisboaPortugal Clínica São João de Deus 1700-048 LisboaPortugal REQUIMTE/LAQV(Rede de Química e Tecnologia/Laboratório Associado para a Química Verde) Instituto Superior de EngenhariaInstituto Politécnico do Porto4051-401 PortoPortugal Hospital SoERAD 2560-312 Torres VedrasPortugal Centro de Estudos Avançados em Direito“Francisco Suarez ”1749-024 LisboaPortugal

Background:Pain associated with cancer is one of the greatest causes of reduced quality of life in *** is one of the treatments used to address this issue,with the great advantage of having little or no side effects,especially when compared with pharmacological ***:The aim of this systematic review and meta-analysis was to evaluate the current evidence regarding the efficacy of acupuncture for cancer *** strategy:Six electronic databases(PubMed,EBSCo,Cochrane Library,Scielo,b-on and Scopus)were searched for relevant articles about pain relief in cancer patients from their beginning until 2022using MeSH terms such as“acupuncture,”“electroacupuncture,”“ear acupuncture,”“acupuncture analgesia,”“oncological pain,”and“cancer pain.”Inclusion criteria:Studies included were randomized controlled trials(RCTs)where acupuncture was compared with no treatment,placebo acupuncture or usual *** extraction and analysis:Three independent reviewers participated in data extraction and evaluation of risk of bias,and a meta-analysis was *** primary outcome was pain intensity,measured with the visual analog scale,numeric rating scale,or brief pain *** outcomes also assessed were quality of life,functionality,xerostomia,pain interference,and analgesic *** were expressed as standardized mean difference(SMD)with 95%confidence interval(CI).Results:Sixteen RCTs with a total of 1124 participants were included in the meta-analysis,with the majority of the studies presenting a low or unclear risk of *** was more effective in reducing pain than no treatment(SMD=–0.90,95%CI[–1.68,–0.12]),sham acupuncture(SMD=–1.10,95%CI[–1.59,–0.61])or usual care(SMD=–1.16,95%CI[–1.38,–0.93]).Conclusion:The results of this study suggest that acupuncture may be an effective intervention to reduce pain associated with *** some limitations due to the low quality and small sample size of some included st

关键词： Acupuncture Cancer pain Meta-analysis Systematic review

MDCN:Modified Dense Convolution Network Based Disease Classification in Mango Leaves

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Computers, Materials & Continua 2024年第2期78卷 2511-2533页

作者： Chirag Chandrashekar k.P.Vijayakumar k.Pradeep A.Balasundaram School of Computer Science and Engineering Vellore Institute of Technology(VIT)ChennaiIndia Center for Cyber Physical Systems School of Computer Science and EngineeringVellore Institute of Technology(VIT)ChennaiIndia

The most widely farmed fruit in the world is *** the production and quality of the mangoes are hampered by many *** diseases need to be effectively controlled and ***,a quick and accurate diagnosis of the disorders is *** convolutional neural networks,renowned for their independence in feature extraction,have established their value in numerous detection and classification ***,it requires large training datasets and several parameters that need careful *** proposed Modified Dense Convolutional Network(MDCN)provides a successful classification scheme for plant diseases affecting mango *** model employs the strength of pre-trained networks and modifies them for the particular context of mango leaf diseases by incorporating transfer learning *** data loader also builds mini-batches for training the models to reduce training ***,optimization approaches help increase the overall model’s efficiency and lower computing *** employed on the MangoLeafBD Dataset consists of a total of 4,000 *** the experimental results,the proposed system is compared with existing techniques and it is clear that the proposed algorithm surpasses the existing algorithms by achieving high performance and overall throughput.

关键词： Leaf disease detection deep convolutional neural networks transfer learning optimization MangoLeafBD Dataset