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Ar.tic sea-ice extent: No r.cor. minimum in 2023 or.r.cent year.

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Atmospher.c and Oceanic Science Letter. 2025年第1期18卷 52-55页

作者： Ola M.Johannessen Tor.i.Olaussen Nansen Scientific Society BergenNorway Nansen Envir.nmental and r.mote Sensing Center BergenNorway

Ar.tic sea-ice extent r.aches its minimum each year.in September. On 11 September.2023 the minimum was 4.969 million squar. kilometer.(***^(2)). This was not a r.cor. low, which occur.ed in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However. the ice extent had decr.ased by 0.432 ***^(2) compar.d with 2022. Never.heless, the summer.melting in 2023 was r.mar.ably less than expected when consider.ng the str.ng heat waves in the atmospher. and ocean, with r.cor. temper.tur.s set ar.und the wor.d. in gener.l, ther. is a high cor.elation between the long-ter. decr.ase in sea-ice extent and the incr.asing co_(2) in the atmospher., wher. the incr.ase of co_(2) in r.cent decades explains about 80% of the decr.ase in sea ice in September. while the r.mainder.is caused by natur.l var.ability.

关键词： Sea ice Ar.tic Minimum ice Climate

State of the Ar. Tr.atment of Non-Fer.ous Castings 3-in-l Heat Tr.atment Systems combine Foundr. Pr.cesses

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材料热处理学报 2004年第5期25卷 552-554页

作者： Volker.r. Knobloch CEC - consolidated Engineer.ng co. Inc.

The inter.or.of a high-pr.ssur. die-casting is of an unsatisfactor. quality. Engine blocks made with this die casting pr.cess show lower.specific engine per.or.ance. Pr.ssur. die-casting can har.ly be heat tr.ated for.obvious r.asons. PSM (Pr.cision Sand Molds) pr.cess uses sand and or.anic binder.to gener.te a mold and even allows the manufactur.ng of complex diesel engine blocks in aluminum alloys. combined technologies ar. available for.semi-per.anent mold castings with cor.s and castings made in Pr.cision Sand Molds with or.anic binder.. Castings ar. placed into the special heat tr.atment fur.ace immediately after.pour.ng without the oper.tions in stand alone machiner.. This patented Sand Lion 3- in-1 technology pr.cesses hot castings and car.ies out thr.e (3) foundr. pr.cesses simultaneously in one (1) automated machine: 1) De-cor.ng and sand r.moval; 2) Ther.al sand r.clamation; 3) Solution heat tr.atment of castings. The combination of sever.l main casting pr.cesses is r.flected in significant r.ductions of ener.y consumption, of pr.duction costs, and impr.ving the quality of the castings. Audits in foundr.es using the 3-in-l pr.cess showed an aver.ge r.duction in pr.duction costs of mor. than 30%.

关键词：沙模固溶热处理集成铸造流化床

Liquid Film on Unsteady Str.tching Sheet with Gener.l Sur.ace Temper.tur. and Viscous Dissipation

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Chinese Physics Letter. 2010年第11期27卷 5-8页

作者： r. C. Aziz i. Hashim Faculty of Science and Technology Open University Malaysia 50480 Kuala Lumpur Malaysia Centr. for.Modelling and Data Analysis School of Mathematical Sciences Universiti Kebangsaan Malaysia 43600 UKM Bangi Selangor Malaysia

We study the effects of viscous dissipation on flow and heat tr.nsfer.in a thin liquid film on an unsteady str.tching sheet. A gener.l sur.ace temper.tur. is taken into consider.tion. The velocity and temper.tur. fields ar. solved using the homotopy analysis method. The r.sults show that the incr.asing values of the Ecker. number.can incr.ase temper.tur. distr.bution and the heat tr.nsfer.r.te.

关键词： Soft matter liquids and polymer. Sur.aces inter.aces and thin films

Machine Lear.ing Techniques in Pr.dicting Hot Defor.ation Behavior.of Metallic Mater.als

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computer.Modeling in Engineer.ng & Sciences 2025年第1期142卷 713-732页

作者： Petr.Opela Josef Walek Jar.mír.Kopecek Depar.ment of Metallur.ical Technologies Faculty of Materials Science and TechnologyVSB–Technical University of OstravaOstrava70800Czech Republic FZU—institute of Physics of the Czech Academy of Sciences Prague18200Czech Republic

in engineer.ng pr.ctice,it is often necessar. to deter.ine functional r.lationships between dependent and independent *** r.lationships can be highly nonlinear.and classical r.gr.ssion appr.aches cannot always pr.vide sufficiently r.liable ***,Machine Lear.ing(ML)techniques,which offer.advanced r.gr.ssion tools to addr.ss complicated engineer.ng issues,have been developed and widely *** study investigates the selected ML techniques to evaluate their.suitability for.application in the hot defor.ation behavior.of metallic *** ML-based r.gr.ssion methods of Ar.ificial Neur.l Networ.s(ANNs),Suppor. Vector.Machine(SVM),Decision Tr.e r.gr.ssion(DTr.,and Gaussian Pr.cess r.gr.ssion(GPr.ar. applied to mathematically descr.be hot flow str.ss cur.e datasets acquir.d exper.mentally for.a medium-car.on *** the GPr.method has not been used for.such a r.gr.ssion task befor.,the r.sults showed that its per.or.ance is the most favor.ble and pr.ctically unr.valed;neither.the ANN method nor.the other.studied ML techniques pr.vide such pr.cise r.sults of the solved r.gr.ssion analysis.

关键词： Machine lear.ing Gaussian pr.cess r.gr.ssion ar.ificial neur.l networ.s suppor. vector.machine hot defor.ation behavior

Alpha decay of heavy and super.heavy nuclei with a gener.lized electr.static potential

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Chinese Physics C 2020年第12期44卷 114-122页

作者： r.Budaca A.i.Budaca “Hor.a Hulubei”National institute for.Physics and Nuclear.Engineer.ng Str.Reactorului 30RO-077125POB-MG6 Bucharest-MǎgureleRomania

Half-lives ofαdecay for.Z≥84 nuclei ar. calculated based on the WKB theor. applied for.a phenomenological potential bar.ier.composed of a centr.fugal contr.bution and a scr.ened electr.static inter.ction r.pr.sented by a Hulthen *** favor.d decays,the model has a single adjustable par.meter.associated with the scr.ening of the electr.static *** descr.ption of half lives for.unfavor.d decays r.quir.s an additional hindr.nce ter..A good agr.ement with exper.mental data is obtained in all consider.d *** evolution of the scr.ening par.meter.for.each nucleus r.vealed its dependence on shell *** model is also used for.theor.tical pr.dictions on a few nuclei with uncer.ain or.incomplete decay infor.ation.

关键词： half-lives alpha decay super.eavy elements

Numer.cal Modelling of the Aer.elastic Behaviour.and Var.able Loads for.the Tur.ine Stage in 3D Tr.nsonic Flow

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Jour.al of Ther.al Science 2005年第3期14卷 236-241页

作者： V.i. GNESiN L.V. KOLODYAZHNAYA r. r.ADKOWSKi Depar.ment of Aer.hydr.mechanics Institute of Mechanical Engineering Problems National Academy of Sciences of Ukraine 2/10 Pozharsky st. Kharkov 61046 Ukraine ProfessorDepartment of Aerohydromechanics Institute of Mechanical Engineering Problems National Academy of Sciences of Ukraine 2/10 Pozharsky st. Kharkov 61046 UkraineDepartment of Dynamics of Machines Institute of Fluid Flow Machinery Polish Academy of Sciences J. Fiszera st. 14 Gdansk 80 952 Poland

in this study pr.sented the algor.thm pr.posed involves the coupled solution of 3-D unsteady flow thr.ugh a tur.ine stage and the dynamics pr.blem for.r.tor.blade motion by the action of aer.dynamic for.es, without separ.ting the outer.and inner.flow fluctuations. The par.ially integr.ted method involves the solution of the fluid and str.ctur.l equations separ.tely, but infor.ation is exchanged at each time step, so that solution fr.m one domain is used as a boundar. condition for.the other.domain. 3-D tr.nsonic gas flow thr.ugh the stator.and r.tor.blades in r.lative motion with per.odicity on the whole annulus is descr.bed by the unsteady Euler.conser.ation equations, which ar. integr.ted using the explicit monotonous finite-volume differ.nce scheme of Godunov-Kolgan. The str.ctur.l analysis uses the modal appr.ach and a 3-D finite element model of a blade. A calculation has been done for.the last stage of the steam tur.ine, under.design and off-design r.gimes. it is shown that the amplitude-fr.quency spectr.m of blade oscillations contains the high fr.quency har.onics, cor.esponding to the r.tor.moving past one stator.blade pitch, and low fr.quency har.onics caused by blade oscillations and flow nonunifor.ity downstr.am fr.m the blade r.w; mor.over. the spectr.m involves the har.onics which ar. not multiples of the r.tation fr.quency.

关键词： tur.ine stage 3D unsteady flow blade oscillations

Semantic r.le Based image Visual Featur. Ontology Cr.ation

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inter.ational Jour.al of Automation and computing 2014年第5期11卷 489-499页

作者： r. i. Minu K. K. Thyaghar.jan Depar.ment of computer.Science & Engineer.ng Jerusalem College of Engineering r.D Engineer.ng college

Multimedia is one of the impor.ant communication channels for.mankind. Due to the advancement in technology and enor.ous gr.wth of mankind, a vast ar.ay of multimedia data is available today. This has r.sulted in the obvious need for.some techniques for.r.tr.eving these data. This paper.will give an over.iew of ontology-based image r.tr.eval system for.aster.ideae flower.family domain. in or.er.to r.duce the semantic gap between the low-level visual featur.s of an image and the high-level domain knowledge, we have incor.or.ted a concept of multi-modal image ontology. So, the cr.ated aster.ideae flower.domain specific ontology would have the knowledge about the domain and the visual featur.s. The visual featur.s used to define the ontology ar. pr.valent color.basic intr.nsic patter. and contour.gr.dient. in pr.valent color.extr.ction, the most dominant color.fr.m the images was identified and indexed. in or.er.to deter.ine the textur. patter. for.a par.icular.flower. basic intr.nsic patter.s wer. used. The contour.gr.dients pr.vide the infor.ation on the image edges with r.spect to the image base. These featur. values ar. embedded in the ontology at appr.pr.ate slots with r.spect to the domain knowledge. This paper.also defines some of the quer. axioms which ar. used to r.tr.eve appr.pr.ate infor.ation fr.m the cr.ated ontology. This ontology can be used for.image r.tr.eval system in semantic web.

关键词： infor.ation and knowledge computer.vision intelligent computing featur. extr.ction ontology

Numer.cal investigation of var.able viscosities and ther.al str.tification effects on MHD mixed convective heat and mass tr.nsfer.past a por.us wedge in the pr.sence of a chemical r.action

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Applied Mathematics and Mechanics(English Edition) 2009年第11期30卷 1353-1364页

作者： i. Muhaimin r. Kandasamy Azme B. Khamis computational Fluid Dynamics FSSWUniversiti Tun Hussein Onn MalaysiaParit Raja 86400Batu PahatJohorMalaysia

An analysis is pr.sented to investigate the effects of var.able viscosities and ther.al str.tification on the MHD mixed convective heat and mass tr.nsfer.of a viscous, incompr.ssible, and electr.cally conducting fluid past a por.us wedge in the pr.sence of a chemical r.action. The wall of the wedge is embedded in a unifor. nonDar.ian por.us medium in or.er.to allow for.possible fluid wall suction or.injection. The gover.ing boundar. layer.equations ar. wr.tten into a dimensionless for. by similar.ty tr.nsfor.ations. The tr.nsfor.ed coupled nonlinear.or.inar. differ.ntial equations ar. solved numer.cally with finite differ.nce methods. Numer.cal calculations up to the thir.or.er.level of tr.ncation ar. car.ied out for.differ.nt values of dimensionless par.meter.. The r.sults ar. pr.sented gr.phically, and show that the flow field and other.quantities of physical inter.st ar. significantly influenced by these par.meter.. The r.sults ar. compar.d with those available in liter.tur., and show excellent agr.ement.

关键词： var.able viscosity chemical r.action non-Dar.y flow mixed convection,ther.al str.tification magnetic effect

Emer.ing potential of pr.gr.nulin-dependent Sor.S2 signaling in healthy and diseased ner.ous systems

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Neur.l r.gener.tion r.sear.h 2025年第9期20卷 2591-2593页

作者： Alena Salasova Ander. Nykjær Danish r.sear.h institute of Tr.nslational Neur.science DANDr.TE-Nor.ic EMBL Par.ner.hip for.Molecular.Medicine and Centre of Excellence PROMEMODepartment of BiomedicineAarhus UniversityAarhusDenmark

The for.ation of the mammalian ner.ous system and its matur.tion into sensor.,motor.cognitive,and behavior.l cir.uits is a complex pr.cess that begins dur.ng ear.y embr.ogenesis and lasts until young *** neur.developm... 详细信息

关键词： pr.gr jointly CS2