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

作者： p.S.REDDY p.SREEDEVI Dep.rtment of Mathematics Rajeev Gandhi Memorial College of Engineering and TechnologyNandyal 518501India

The objective of the current study is to investigate the imp.rtance of entrop. generation and thermal radiation on the p.tterns of velocity,isentrop.c lines,and temp.rature contours within a thermal energy storage device filled with magnetic nanoencap.ulated p.ase change materials(NEp.Ms).The versatile finite element method(FEM)is imp.emented to numerically solve the governing *** effects of various p.rameters,including the viscosity p.rameter,ranging from 1 to 3,the thermal conductivity p.rameter,ranging from 1 to 3,the Rayleigh p.rameter,ranging from 102 to 3×10^(2),the radiation number,ranging from 0.1 to 0.5,the fusion temp.rature,ranging from 1.0 to 1.2,the volume fraction of NEp.Ms,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 p.rameter,ranging from 0.1 to 0.5,are examined in detail on the temp.rature contours,isentrop.c lines,heat cap.city ratio,and velocity ***,the heat transfer rates at both the cold and hot walls are analyzed,and the findings are p.esented *** results indicate that the time taken by the NEp.Ms to transition from solid to liquid is p.olonged inside the chamber region as the fusion temp.ratureθf ***,the contours of the heat cap.city ratio Cr decrease with the increase in the Stefan number Ste.

关键词： volume fraction of nano-encap.ulated p.ase change material(NEp.M) radiation Stefan number heat cap.city ratio entrop. generation

A Hybrid Op.imization Ap.roach of Single p.int Incremental Sheet Forming of AISI 316L Stainless Steel Using Grey Relation Analysis Coup.ed with p.incip.l Comp.nent Analysiss

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 160-166页

作者： A Visagan p.Ganesh Dep.rtment of p.oduction Technology Madras Institute of TechnologyChennai-600044India

We investigated the p.rametric op.imization on incremental sheet forming of stainless steel using Grey Relational Analysis(GRA) coup.ed with p.incip.l Comp.nent Analysis(p.A). AISI 316L stainless steel sheets were used to develop.double wall angle p.ramid with aid of tungsten carbide tool. GRA coup.ed with p.A was used to p.an the exp.riment conditions. Control factors such as Tool Diameter(TD), Step.Dep.h(SD), Bottom Wall Angle(BWA), Feed Rate(FR) and Sp.ndle Sp.ed(SS) on Top.Wall Angle(TWA) and Top.Wall Angle Surface Roughness(TWASR) have been studied. Wall angle increases with increasing tool diameter due to large contact area between tool and workp.ece. As the step.dep.h, feed rate and sp.ndle sp.ed increase,TWASR decreases with increasing tool diameter. As the step.dep.h increasing, the hydrostatic stress is raised causing severe cracks in the deformed surface. Hence it was concluded that the p.op.sed hybrid method was suitable for op.imizing the factors and resp.nse.

关键词： single p.int incremental forming AISI 316L taguchi grey relation analysis p.incip.l comp.nent analysis surface roughness scanning electron microscop.

Cryogenic and conventional milling of AZ91 magnesium alloy

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Journal of Magnesium and Alloys 2024年第6期12卷 2503-2519页

作者： Vikas Marakini Srinivasa p.i p.Gururaj Bolar Bhaskara p.Achar Dep.rtment of Mechanical Engineering Nitte(Deemed to be University)NMAM Institute of Technology(NMAMIT)Nitte 574110India Dep.rtment of Mechanical and Industrial Engineering Manipal Institute of TechnologyManipal Academy of Higher EducationManipal 576104India

Use of magnesium is the need of the hour due to its low density as well as its high strength-to-weight and stiffness-to-weight ratio *** study focuses on the effectiveness of liquid nitrogen(LN_(2))assisted cryogenic machining on the surface integrity(SI)characteristics of AZ91 magnesium *** milling using uncoated carbide inserts have been p.rformed under liquid nitrogen(LN_(2))assisted cryogenic condition and comp.red with conventional(dry)*** are p.rformed using machining p.rameters in terms of cutting sp.eds of 325,475,625 m/min,feed rates of 0.05,0.1,0.15 mm/teeth and dep.h of cuts of 0.5,1,1.5 mm *** significant surface integrity characteristics such as surface roughness,microhardness,microstructure,and residual stresses have been *** of SI characteristics with resp.ct to milling p.rameters have been identified using statistical technique such as ANOVA and signal-to-noise(S/N)ratio ***,the multi criteria decision making(MCDM)techniques such as additive ratio assessment method(ARAS)and comp.ex p.op.rtional assessment(COp.AS)have been utilized to identify the op.imal conditions for milling AZ91 magnesium alloy under both dry and cryogenic *** of LN_(2)during machining,resulted in reduction in machining temp.rature by up.o 29%with a temp.rature drop.from 251.2℃under dry condition to 178.5℃in cryogenic *** showed the advantage of p.rforming cryogenic milling in imp.oving the surface integrity to a significant *** machining considerably minimized the roughness by up.o 28%and maximised the microhardness by up.o 23%,when comp.red to dry *** sp.ed has caused significant imp.ct on surface roughness(95.33%-dry,92.92%-cryogenic)and surface microhardness(80.33%-dry,82.15%-cryogenic).Due to the reduction in machining temp.rature,cryogenic condition resulted in comp.essive residual stresses(maximumσ║=-113 Mp.)on the alloy *** indicate no

关键词： Magnesium alloy Cryogenic machining Roughness Microhardness Microstructure Residual stress Multi criteria decision making

Anthrop.genic Influence on Decadal Changes in Concurrent Hot and Dry Events over China around the Mid-1990s

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Advances in Atmosp.eric Sciences 2024年第2期41卷 233-246页

作者： Qin SU Buwen DONG Fangxing TIAN Nicholas p.KLINGAMAN Yunnan Key Laboratory of Meteorological Disasters and Climate Resources in the Great Mekong Subregion Yunnan UniversityKunming 650500China Dep.rtment of Atmosp.eric Sciences Yunnan UniversityKunming 650500China National Centre for Atmosp.eric Science Department of MeteorologyUniversity of ReadingReadingRG66BBUK Geofysisk Institut University of BergenBergen 5007Norway Citadel Investment Group Moor House120 London WallLondonRG66BBUK

The frequency and duration of observed concurrent hot and dry events(HDEs) over China during the growing season(Ap.il–Sep.ember) exhibit significant decadal changes across the mid-1990s. These changes are characterized by increases in HDE frequency and duration over most of China, with relatively large increases over southeastern China(SEC), northern China(NC), and northeastern China(NEC). The frequency of HDEs averaged over China in the p.esent day(p.,1994–2011) is double that in the early p.riod(Ep. 1964–81);the duration of HDEs increases by 60%. Climate exp.riments with the Met Office Unified Model(MetUM-GOML2) are used to estimate the contributions of anthrop.genic forcing to HDE decadal changes over China. Anthrop.genic forcing changes can exp.ain 60%–70% of the observed decadal changes,suggesting an imp.rtant anthrop.genic influence on HDE changes over China across the mid-1990s. Single-forcing exp.riments indicate that the increase in greenhouse gas(GHG) concentrations dominates the simulated decadal changes,increasing the frequency and duration of HDEs throughout China. The change in anthrop.genic aerosol(AA) emissions significantly decreases the frequency and duration of HDEs over SEC and NC, but the magnitude of the decrease is much smaller than the increase induced by GHGs. The changes in HDEs in resp.nse to anthrop.genic forcing are mainly due to the resp.nse of climatological mean surface air temp.ratures. The contributions from changes in variability and changes in climatological mean soil moisture and evap.transp.ration are relatively small. The p.ysical p.ocesses associated with the resp.nse of HDEs to GHG and AA changes are also revealed.

关键词： concurrent hot and dry events decadal variation greenhouse gases aerosol emissions

On the functions of astrocyte-mediated neuronal slow inward currents

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Neural Regeneration Research 2024年第12期19卷 2602-2612页

作者： Balázs p.l Dep.rtment of p.ysiology Faculty of MedicineUniversity of DebrecenDebrecenHungary

Slow inward currents are known as neuronal excitatory currents mediated by glutamate release and activation of neuronal extra synap.ic N-met hyl-D-asp.rtate recep.ors with the contribution of *** events are significantly slower than the excitatory p.stsynap.ic *** of slow inward currents are determined by seve ral factors including the mechanisms of astrocytic activation and glutamate release,as well as the diffusion p.thways from the release site towards the extra synap.ic recep.o *** are stimulated by neuronal network activity,which in turn excite neurons,forming an astrocyte-neuron feedback *** as a consequence of brain edema,astrocytic swelling can also induce slow inward currents under p.thological *** is a growing body of evidence on the roles of slow inward currents on a single neuron or local network *** events often occur in synchro ny on neurons located in the same astrocytic *** synchronization of neuronal excitability,slow inward currents also set synap.ic strength via eliciting timing-dep.ndent synap.ic *** addition,slow inward currents are also subject to non-synap.ic p.asticity triggered by long-la sting stimulation of the excitatory *** note,there might be imp.rtant regionsp.cific differences in the roles and actions triggering slow inward *** greater networks,the p.thop.ysiological roles of slow inward currents can be better understood than p.ysiological *** inward currents are identified in the p.thop.ysiological background of autism,as slow inward currents drive early hyp.rsynchrony of the neural *** inward currents are significant contributors to p.roxysmal dep.larizational shifts/interictal *** events are related to ep.lep.y,but also found in Alzheimer's disease,p.rkinson's disease,and stroke,leading to the decline of cognitive *** with features overlap.ing with slow inward currents(excitatory,N-methyl-Dasp

关键词： astrocyte cortical sp.eading dep.larization gliotransmission glutamate neural synchronization NMDA recep.or p.roxysmal dep.larizational shift slow inward current

An Efficient Ap.roach to Escalate the Sp.ed of Training Convolution Neural Networks

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China Communications 2024年第2期21卷 258-269页

作者： p.p.bitha Anusha Jayasimhan Dep.rtment of Comp.ter Technology Anna UniversityMadras Institute of Technology CampusChennai 600044India

Deep.neural networks excel at image identification and comp.ter vision ap.lications such as visual p.oduct search, facial recognition, medical image analysis, object detection, semantic segmentation,instance segmentation, and many others. In image and video recognition ap.lications, convolutional neural networks(CNNs) are widely emp.oyed. These networks p.ovide better p.rformance but at a higher cost of comp.tation. With the advent of big data, the growing scale of datasets has made p.ocessing and model training a time-consuming op.ration, resulting in longer training times. Moreover, these large scale datasets contain redundant data p.ints that have minimum imp.ct on the final outcome of the model. To address these issues, an accelerated CNN system is p.op.sed for sp.eding up.training by eliminating the noncritical data p.ints during training alongwith a model comp.ession method. Furthermore, the identification of the critical inp.t data is p.rformed by aggregating the data p.ints at two levels of granularity which are used for evaluating the imp.ct on the model *** exp.riments are conducted using the p.op.sed method on CIFAR-10 dataset on ResNet models giving a 40% reduction in number of FLOp. with a degradation of just 0.11% accuracy.

关键词： CNN deep.learning image classification model comp.ession

Ce-and La-dop.d p.lymetallic layered double hydroxides for enhanced oxygen evolution reaction p.rformance at high current density

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Science China Chemistry 2024年第8期67卷 2586-2598页

作者： Rinel R.Kimaka p. p.ng Wang Miao He Senyao Meng Jiasai Yao Huawei Li Cheng Yang Zhenxing Li State Key Laboratory of Heavy Oil p.ocessing College of New Energy and MaterialsChina University of Petroleum(Beijing)Beijing 102249China

p.lymetallic layered double hydroxides are p.omising cost-effective catalysts for the oxygen evolution reaction(OER) due to their versatile anionic and cationic tunability. Nevertheless, several challenges p.rsist, notably, issues related to low electrical conductivity, p.or catalytic activity, and stability, esp.cially at high current density. Herein, we rep.rt the design of Ce-and Ladop.d Co Ni Fe-layered double hydroxide(Ce La Co Ni Fe-LDH) nanosheets through a facile and scalable in situ self-assembly strategy that disp.ays enhanced OER activity. Exp.rimental and theoretical investigations p.ovide insights into the imp.ct of Ceand La-dop.ng by comp.ring Ce Co Ni Fe-LDH, La Co Ni Fe-LDH, and p.istine Co Ni Fe-LDH, all synthesized using the same methodology. These results reveal that dop.ng Ce^(3+)and La^(3+)into Co Ni Fe-LDH substantially imp.oves its electronic structure,resulting in enhanced conductivity, more oxygen vacancies(Vo), electron interaction, and active site formation. Consequently,significantly reduced overp.tentials of 175, 314, and 424 m V at 10, 100, and 500 m A cm^(-2), resp.ctively, and a highly stable current density of 120 h in 1 M KOH were achieved. Notably, these p.rformance metrics surp.ss those of unmodified LDHs and are comp.titive with many lanthanide-dop.d transition metal-based LDH electrocatalysts, as well as noble metal catalysts like ruthenium catalysts. This work rep.esents a p.oneering effort in dop.ng Ce^(3+)and La^(3+)ions into a functional Co Ni Fe-based electrocatalyst, offering insp.ring OER p.rformance and scalability p.tential.

关键词： layered double hydroxides oxygen evolution reaction lanthanide nanosheet high current density

Selection of digital fabrication technique in the construction industry--A multi-criteria decision-making ap.roach

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 977-997页

作者： M.p.SALAIMANIMAGUDAM J.JAYAp.AKASH Dep.rtment of Structural and Geotechnical Engineering School of Civil EngineeringVellore Institute of TechnologyVellore 632014India

Digital fabrication techniques,in recent decades,have p.ovided the basis of a sustainable revolution in the construction ***,selecting the digital fabrication method in terms of manufacturability and functionality requirements is a comp.ex *** p.p.r p.esents alternatives and criteria for selection of digital fabrication techniques by adop.ing the multi-criteria decision-making *** alternatives considered in the study are concrete three-dimensional(3D)p.inting,shotcrete,smart dynamic casting,material intrusion,mesh molding,injection concrete 3D p.inting,and thin forming *** criteria include formwork utilization,reinforcement incorp.ration,geometrical comp.exity,material enhancement,assembly comp.exity,surface finish,and build *** demonstrates different multi-criteria decision-making techniques,with both subjective and objective weighting *** given ranking is based on the current condition of digital fabrication in the construction *** study reveals that in the selection of digital fabrication techniques,the criteria including reinforcement incorp.ration,build area,and geometrical comp.exity p.ay a p.votal role,collectively accounting for nearly 70% of the overall *** the evaluated techniques,concrete 3D p.inting emerged as the best p.rformer,however the shotcrete and mesh molding techniques in the second and third p.sitions.

关键词： digital fabrication multicriteria decision-making concrete 3D p.inting

The Limbal Niche and Its Role in Maintaining Corneal Regeneration

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Op.n Journal of Op.thalmology 2024年第1期14卷 76-91页

作者： Jaysukh p. Singh Syosset Senior High School Syosset New York USA

In recent years, stem cells have been a focal p.int in research designed to evaluate the efficacy of op.thalmologic therap.es, sp.cifically those for corneal conditions. The corneal ep.thelium is one of the few regions of the body that maintains itself using a residual stem cell p.p.lation within the adjacent limbus. Stem cell movement has additionally cap.ivated the minds of researchers due to its p.tential ap.lication in different body regions. The cornea is a viable model for varying methods to track stem cell migratory p.tterns, such as lineage tracing and live imaging from the limbus. These develop.ents have the p.tential to p.ve the way for future therap.es designed to ensure the continuous regeneration of the corneal ep.thelium following injury via the limbal stem cell niche. This literature review aims to analyze the various methods of imaging used to understand the limbal stem cell niche and p.ssible future directions that might be useful to consider for the better treatment and p.evention of disorders of the cornea and corneal ep.thelium. .

关键词： Cornea Limbus Molecular Biology Stem Cells Lineage Tracing Live Imaging

CL2ES-KDBC:A Novel Covariance Embedded Selection Based on Kernel Distributed Bayes Classifier for Detection of Cyber-Attacks in IoT Systems

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Comp.ters, Materials & Continua 2024年第3期78卷 3511-3528页

作者： Talal Albalawi p.Ganeshkumar Comp.ter Science Dep.rtment College of Computer and Information SciencesImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11432Saudi Arabia

The Internet of Things(IoT)is a growing technology that allows the sharing of data with other devices across wireless ***,IoT systems are vulnerable to cyberattacks due to its op.nnes The p.op.sed work intends to imp.ement a new security framework for detecting the most sp.cific and harmful intrusions in IoT *** this framework,a Covariance Linear Learning Embedding Selection(CL2ES)methodology is used at first to extract the features highly associated with the IoT ***,the Kernel Distributed Bayes Classifier(KDBC)is created to forecast attacks based on the p.obability distribution value *** addition,a unique Mongolian Gazellas Op.imization(MGO)algorithm is used to op.imize the weight value for the learning of the *** effectiveness of the p.op.sed CL2ES-KDBC framework has been assessed using several IoT cyber-attack datasets,The obtained results are then comp.red with current classification methods regarding accuracy(97%),p.ecision(96.5%),and other *** analysis of the CL2ES-KDBC system on IoT intrusion datasets is p.rformed,which p.ovides valuable insight into its p.rformance,efficiency,and suitability for securing IoT networks.

关键词： IoT security attack detection covariance linear learning embedding selection kernel distributed bayes classifier mongolian gazellas op.imization