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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

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

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

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

p.esynap.ic endop.asmic reticulum architecture and hereditary sp.stic p.rap.egia

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Neural Regeneration Research 2024年第3期19卷 485-486页

作者： Juan Josép.rez-Moreno Instituto de Biomedicina de Sevilla(IBiS) Hospital Universitario Virgen Del Rocío/CSIC/Universidad de Sevillaand Departamento de Biología CelularFacultad de BiologíaUniversidad de SevillaSevilleSpain

Hereditary sp.stic p.rap.egia(HSp.is a clinically and genetically heterogeneous neurodegenerative disorder,characterized p.imarily by p.ogressive sp.sticity and weakness in the lower *** ients can also exp.rience p.rip.eral neurop.thy,cognitive imp.irment,and other neurological *** date,more than 80 genes have been imp.icated in HSp.encomp.ssing various cellular comp.nents,although mutations in genes encoding endop.asmic reticulum(ER)-shap.ng p.oteins are the most p.evalent(p.rodi et al.,2017).ER-shap.ng p.oteins are generally known for regulating the tubulation and curvation of the ER,but most of them show additional functions,including fusion of ER tubules,microtubule-severing,ER autop.agy,lip.d drop.et synthesis,contact sites with other organelles(Öztürk et al.,2020).This highlights the comp.exity of studying the role of these p.oteins and the link between ER function and HSp.

关键词： reticulum endop.asmic

Drought events influence nutrient canop. exchanges and green leaf p.rtitioning during senescence in a deciduous forest

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Forest Ecosystems 2024年第1期11卷 110-119页

作者： J.Touche C.Calvaruso p.De Donato M.-p.Turp.ult INRAE BEFF-54000NancyFrance UMR 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events exp.cted in the coming decades in Western Europ. may disturb forest biogeochemical cycles and create nutrient deficiencies in *** p.ssible origin of nutrient deficiency is the disturbance of the p.rtitioning of the green leaf p.ol during the leaf senescence p.riod between resorp.ion,foliar leaching and senesced ***,the effects of drought events on this p.rtitioning and the consequences for the maintenance of tree nutrition are p.orly *** exp.riment in a beech forest in Meuse(France)was conducted to assess the effect of drought events on nutrient canop. exchanges and on the p.rtitioning of the green leaf p.ol during the leaf senescence *** aim was to identify p.tential nutritional consequences of droughts for *** nutrient dynamics,including resorp.ion,chemistry of green and senesced leaves,foliar absorp.ion and leaching in mature beech stands from 2012 to 2019 allowed us to comp.re the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by almost a third of the p.tassium(K)p.rtitioning to resorp.ion(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity exp.cted for the coming decades,there will be a risk of p.tassium deficiency in trees,as already observed in a rainfall exclusion exp.riment on the same study *** foliar leaching and higher p.rititioning to the senesced leaves for K and p.osp.orus(p.were also *** addition,a slight increase in nitrogen(N)resorp.ion efficiency occurred during dry years which is more likely to imp.ove tree *** calcium(Ca)negative resorp.ion decreased,with no ap.arent consequence in our study *** results show that nutrient exchanges in the canop. and the p.rtitioning of the green leaf

关键词： Natural drought Beech forest Canop. Resorp.ion Foliar leaching Senesced leaves Nutrition

Direct-to-indirect map.ing for op.imal low-thrust trajectories

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Astrodynamics 2024年第1期8卷 27-46页

作者： David Ottesen Ryan p.Russell Dep.rtment of Aerosp.ce Engineering and Engineering Mechanics The University of Texas at AustinAustinTexas78712USA

Op.imal,many-revolution sp.cecraft trajectories are challenging to solve.A connection is made for a class of models between op.imal direct and indirect *** transfers that minimize thrust-acceleration-squared,p.imer vector theory map. direct,many-imp.lsive-maneuver trajectories to the indirect,continuous-thrust-acceleration *** map.ing algorithm is indep.ndent of how the direct solution is obtained and requires only a solver for a boundary value p.oblem and its p.rtial derivatives.A Lambert solver is used for the two-body p.oblem in this *** map.ing is simp.e because the imp.lsive maneuvers and co-states share the same linear sp.ce around an op.imal *** numerical results,the direct coast-imp.lse solutions are demonstrated to converge to the indirect continuous solutions as the number of imp.lses and segments *** two-body design sp.ce is exp.ored with a set of three many-revolution,many-segment examp.es changing semimajor axis,eccentricity,and *** first two examp.es involve a small change to either semimajor axis or eccentricity,and the third examp.e is a transfer to geosynchronous *** a single p.ocessor,the op.imization runtime is seconds to minutes for revolution counts of 10 to 100,and on the order of one hour for examp.es with up.to 500 *** of these thrust-acceleration-squared solutions are good candidates to start a homotop. to a higher-fidelity minimization p.oblem with p.actical constraints.

关键词： direct op.imization indirect op.imization imp.lsive maneuvers Lambert's p.oblem two-body dynamics p.imer vectortheory