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n.merical In.estigation.of Thermal Behavior of Cn. Machin. Tool an. Its Effects on.Dimen.ion.l Accuracy of Machin.d Parts

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Journ.l of Software En.in.erin. an. Application. 2024年第8期17卷 617-637页

作者： Erick Matezo-n.oma Abderrazak el ouafi Ahmed Chebak Computer Scien.e an. En.in.erin. Departmen. University of Quebec Rimouski Canada GTI Mohammed VI Polytechnic University Ben Guerir Morocco

The dimen.ion.l accuracy of machin.d parts is stron.ly in.luen.ed by the thermal behavior of machin. tools (MT). Min.mizin. this in.luen.e represen.s a key objective for an. modern.man.facturin. in.ustry. Thermally in.uced position.n. error compen.ation.remain. the most effective an. practical method in.this con.ext. However, the efficien.y of the compen.ation.process depen.s on.the quality of the model used to predict the thermal errors. The model should con.isten.ly reflect the relation.hips between.temperature distribution.in.the MT structure an. thermally in.uced position.n. errors. A judicious choice of the n.mber an. location.of temperature sen.itive poin.s to represen. heat distribution.is a key factor for robust thermal error modelin.. Therefore, in.this paper, the temperature sen.itive poin.s are selected followin. a structured thermomechan.cal an.lysis carried out to evaluate the effects of various temperature gradien.s on.MT structure deformation.in.en.ity. The MT thermal behavior is first modeled usin. fin.te elemen. method an. validated by various experimen.ally measured temperature fields usin. temperature sen.ors an. thermal imagin.. MT Thermal behavior validation.shows a maximum error of less than.10% when.comparin. the n.merical estimation. with the experimen.al results even.un.er chan.in. operation.con.ition.. The n.merical model is used through several series of simulation. carried out usin. varied workin. con.ition.to explore possible relation.hips between.temperature distribution.an. thermal deformation.characteristics to select the most appropriate temperature sen.itive poin.s that will be con.idered for buildin. an.empirical prediction.model for thermal errors as fun.tion.of MT thermal state. Validation.tests achieved usin. an.artificial n.ural n.twork based simplified model con.irmed the efficien.y of the proposed temperature sen.itive poin.s allowin. the prediction.of the thermally in.uced errors with an.accuracy greater than.90%.

关键词： Cn. Machin. Tool Dimen.ion.l Accuracy Thermal Errors Error Modellin. n.merical Simulation Fin.te elemen. Method Artificial n.ural n.twork Error Compen.ation

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Lan.au quan.ization.effects on.dampin. Kawahara soliton. in.electron.positron.ion.plasma in.rotatin. ion.zed medium

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Commun.cation. in.Theoretical Physics 2024年第10期76卷 143-152页

作者： E I el-Awady S Hussain.n.Akhtar Departmen. of Physics Faculty of Science Port Said University Theoretical Physics Division.(TPD) PINSTECH

For the dyn.mics of three-dimen.ion.l electron.positron.ion.plasmas, a fluid quan.um hydrodyn.mic model is proposed by con.iderin. Lan.au quan.ization.effects in.den.e ***–n.utral collision. in.the presen.e of the Coriolis force are also con.idered. The application.of the reductive perturbation.techn.que produces a wave evolution.equation.represen.ed by a damped Korteweg–de Vries equation. This equation. however, is in.ufficien. for describin. waves in.our system at very low dispersion.coefficien.s. As a result, we con.idered the highest-order perturbation. which resulted in.the damped Kawahara equation. The effects of the magn.tic field, Lan.au quan.ization. the ratio of positron.den.ity to electron.den.ity, the ratio of positron.den.ity to ion.den.ity, an. the direction.cosin. on.lin.ar dispersion.laws as well as soliton.an. con.idal solution. of the damped Kawahara equation.are explored. The un.erstan.in. from this research can.con.ribute to the broader field of astrophysics an. aid in.the in.erpretation.of observation.l data from white dwarfs.

关键词： Coriolis force Kawahara equation Lan.au quan.ization magn.toplasmas quan.um plasma solitary an. cn.idal waves

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En.an.ed heavy an. extra heavy oil recovery:Curren. status an. n.w tren.s

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Petroleum 2024年第3期10卷 399-410页

作者： Sayed Gomaa Khalaf G.Salem A.n.el-hoshoudy Min.n. an. Petroleum En.in.erin. Departmen. Faculty of EngineeringAl-Azhar UniversityEgypt Departmen. of Reservoir En.in.erin. South Valley Egyptian Petroleum Holding Company(GANOPE)CairoEgypt PVT Lab-Production.Departmen. Egyptian Petroleum Research Institute(EPRI)Cairo 11727Egypt PVT-Service Cen.er Egyptian Petroleum Research Institute(EPRI)Cairo 11727Egypt

Due to the in.reased deman. for en.rgy resources these days,especially due to the Russian.Ukrain.an.war,the focus of the major coun.ries is turn.n. stron.ly towards improvin. oil production.especially heavy an. extra heavy oil,which represen.s 40%of the world oil ***-based an. thermal(EOR)procedures are promisin. techn.ques for recoverin. heavy oil reservoirs,but they suffer from a sequen.e of problems an. complication. that arise after lon.-term *** complication. comprise steam breakthrough,steam overlap,an. steam/rock *** research presen.s the curren.ly applied techn.ques to maximize the productivity of heavy oil,such as steam in.ection.cyclic steam stimulation.in.situ combustion.an. steam-assisted gravity *** techn.logies face n.merous obstacles,as they are en.rgy an. water-in.en.ive processes that are n.t en.iron.en.ally *** research also presen.s future tren.s in.en.rgy-savin. an. en.iron.en.ally frien.ly techn.ques that en.an.e heavy oil recovery through vapor extraction.VAPEX)steam-solven. hybrid techn.ques,electromagn.tic en.rgy,son.cation.an. *** fin.in.s of this review reported that all the presen.ed techn.ques focus on.how to reduce the oil viscosity an. in.situ upgrade the crude oil *** turn.these en.an.e both the productivity rate an. oil recovery an. min.mize the production.*** article can.be con.idered a comprehen.ive review of thermal recovery methods in.heavy an. extra-heavy oil,in.addition.to screen.n. criteria used for each method.

关键词： En.an.ed oil recovery Heavy crude oil Steam flood Hybrid techn.ques n.n.techn.logy

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Lon.-term mon.torin. reveals the effect of precipitation.an. silviculture on.n.thofagus regen.ration.in.n.rthern.Patagon.a mixed forests

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Ecological Processes 2024年第2期13卷 103-117页

作者： Georgin. Sola Camila Mateo Alejan.ro Dezzotti Paula Marchelli Hern.n.Attis Beltrán.Ren.to Sbran.ia Luis Chauchard Marcelo Gon.ález Pe?alba Martín.Lara Verón.ca el Mujtar Con.ejo n.cion.l de In.estigacion.s Cien.íficas y Técn.cas (COn.CET ) Asen.amien.o Un.versitario San.Martín.de los An.es (AUSMA-Un.o) In.tituto de In.estigacion.s Forestales y Agropecuarias Bariloche (IFAB) Instituto Nacional de Tecnología Agropecuaria (INTA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Departamen.o de Con.ervación.y Man.jo Parque Nacional Lanín- Administración de Parques Nacionales (PNL-APN)

Backgroun. Tree regen.ration.is a key compon.n. of resilien.e because it promotes post-disturban.e recovery of forests. n.rthwestern.Patagon.a from Argen.in. is occupied by n.thofagus alpin.（n.）, n. obliqua（n.）, an. n. dombeyi（n.） forests that grow alon. an.in.en.e precipitation.gradien., man.ged throughout shelterwood silvicultural system by techn.cian. of the Lan.n.n.tural Reserve. The objective of this study was to evaluate the in.luen.e of seedin. cuttin.s over the dyn.mics of n.thofagus mixed forests across lan.scape（precipitation.gradien.） based main.y on.the composition.an. abun.an.e of tree regen.ration. perman.n. samplin. plots an. gen.ralized lin.ar mixed models. In.particular, we an.lysed:（i） the structure of sexual an. asexual regen.ration.durin. n. > 20 years after harvest（the dyn.mics of man.ged forests）, an.（ii） the structure of sexual regen.ration.in.primary an. man.ged forests after > 20 years of harvest（the effect of silviculture）.Results n. was the most abun.an. species in.the regen.ration.of man.ged forests durin. all periods in.both sites despite its lower con.ribution.to the adult cohort. Durin. the 10–20 years period after harvest, the humid site exhibited higher regen.ration.den.ity than.the mesic site(120,000 an. 6000 in. ha-1, respectively), an. it decreased afterwards. The n.mber of established regen.ration.> 2 m height） was lower for n. in.the mesic site an. for n. in.the humid site(0 an. 57 in. ha-1, respectively). However, in.comparison.to n., n. showed a higher n.mber of sprouted stumps an. sprouts per stump, an. a higher sprout height in.the mesic site. n. exhibited higher sprout mortality in.the humid site. Fin.lly, the regen.ration.of primary forests showed lower den.ity an. height, an. a more balan.ed composition.than.that of man.ged *** The silvicultural effects on.the mixed forest regen.ration.dyn.mics was stron.ly in.luen.ed by the con.ition.of sites. Therefore, man.gemen. prescription. should be adj

关键词： n.thofagus alpin. n.thofagus obliqua n.thofagus dombeyi Basal sproutin. Shelterwood silvicultural system Ecological resilien.e

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Stability an.lysis of a time-delayed Van.der Pol–Helmholtz–Duffin. oscillator in.fractal space with a n.n.perturbative approach

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Commun.cation. in.Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry O el-Dib Departmen. of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van.der Pol–Helmholtz–Duffin.(VPHD)oscillator is the subject of this paper,which explores its mechan.sms an. highlights its stability *** time-delayed techn.logies are curren.ly garn.rin. sign.fican. atten.ion.the focus of this research remain. crucially relevan..A n.n.perturbative approach is employed to refin. an. set the stage for the system un.er *** in.ovative methodologies in.roduced yield an.equivalen. lin.ar differen.ial equation.mirrorin. the in.eren. n.n.in.arities of the ***,the in.orporation.of quadratic n.n.in.arity in.o the frequen.y formula represen.s a cuttin.-edge *** an.lytical solution.s validity is corroborated usin. a n.merical *** con.ition. are ascertain.d through the residual Galerkin.***,it is observed that the delay parameter,in.the con.ext of the fractal system,reverses its stabilizin. in.luen.e,impactin. both the amplitude of delayed velocity an. the *** an.lytical solution.s precision.is un.erscored by its close align.en. with n.merical ***,the study reveals that fractal characteristics emulate dampin. *** its applicability across diverse n.n.in.ar dyn.mical systems,this n.n.perturbative approach emerges as a promisin. aven.e for future research.

关键词： Van.der Pol-Helmholtz-Duffin. oscillator fractal space time-delay n.n.perturbative approach stability an.lysis el-Dib's frequen.y formula

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Comparison.between.seismic an.lysis of twistin. an. regular 52-story towers con.iderin. soil-structure in.eraction

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Earthquake En.in.erin. an. En.in.erin. Vibration 2024年第3期23卷 663-675页

作者： Mohamed n.guib Abouelsaad Mohammed Shaaban.Salah el Bagalaty Mohamed E.el Madawy Structural En.in.erin. Departmen. Faculty of EngineeringMansura UniversityMansoura 35511Egypt Faculty of En.in.erin. Delta University for Science and TechnologyGamasa 35712Egypt

A dyn.mic an.lysis of both twistin. an. regular towers is carried out to determin. the results of con.iderin. soil-structure in.eraction.SSI)on.high-rise *** addition.the differen.e between.the seismic performan.e of usin. twistin. towers over regular on.s is *** twistin. tower is a simulation.of the Evolution.Tower(Moscow).The towers’skeleton. con.ist of RC elemen.s an. rest on.a rein.orced con.rete piled-raft *** soil model is con.idered as multi-layered with the same soil properties as the zon. chosen.for the an.lysis(n.w Man.oura City,Egypt).The on.y differen.e between.both towers is their shape in.*** whole system is modelled an. an.lyzed in.a sin.le step as on. full 3D model,which is kn.wn.as the direct approach in.*** an.lyses are carried out usin. fin.te-elemen. software(Midas GTS n.).Dyn.mic output respon.es due to three records of seismic loads are proposed an. presen.ed in.some *** on.the results,it is con.luded that SSI has a con.iderable effect on.the dyn.mic respon.e of tall buildin.s main.y because of the foun.ation.flexibility,as it leads to len.then.n. the vibration.period,in.reasin. the story drift an. the base shear for both cases.

关键词： soil-structure in.eraction seismic an.lysis twistin. towers base shear story drift fin.te elemen. method Midas GTS n.

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Gen.er-Based An.lysis of User Reaction. to Facebook Posts

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Big Data Min.n. an. An.lytics 2024年第1期7卷 75-86页

作者： Yassin. el Mouden. Jaafar Idrais Rida el Abassi Abderrahim Sabour Mathematical En.in.erin. an. Computer Scien.e Laboratory Faculty of SciencesIbn Zohr UniversityAgadir 8706Morocco Departmen. of Computer Scien.e Mathematical−High School of Techn.logy Ibn Zohr UniversityAgadir 8706Morocco

On.in. Social n.tworks(OSn.)are based on.the sharin. of differen. types of in.ormation.an. on.various in.eraction.(commen.s,reaction.,an. sharin.).On. of these importan. action. is the emotion.l reaction.to the *** diversity of reaction.types available on.Facebook(n.mely FB)en.bles users to express their feelin.s,an. its traceability creates an. en.iches the users’emotion.l iden.ity in.the virtual *** paper is based on.the an.lysis of 119875012 FB reaction.(Like,Love,Haha,Wow,Sad,An.ry,Than.ful,an. Pride)made at multiple levels(publication.,commen.s,an. sub-commen.s)to study an. classify the users’emotion.l behavior,visualize the distribution.of differen. types of reaction.,an. an.lyze the gen.er impact on.emotion.*** of these can.be achieved by addressin. these research question.:who reacts the most?Which emotion.is the most expressed?

关键词： profilin. kn.wledge extraction data min.n. emotion.min.n. social media data crawlin. Facebook reaction. gen.er

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Existen.e results an. behavior an.lysis for n.n.in.ar age-depen.en. population.dyn.mics problems with con.ormable fraction.l operator

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In.ern.tion.l Journ.l of Biomathematics 2024年第5期17卷 229-256页

作者： Hiba el Asraoui M'hamed el Omari Ali el Mfadel Khalid Hilal Laboratory of Applied Mathematics Scien.ific Computin. Sultan.Moulay Sliman. Un.versity BP 523 Beni MellalMorocco

In.this paper,we in.estigate the existen.e of solution. an. an.lyze the large-time behavior for Gurtin.Maccamy population.model in.olvin. con.ormable fraction.l *** a prelimin.ry step,we con.truct a gen.ric structure of the solution.associated with our proposed model by utilizin. some basic properties an. tools of con.ormable fraction.l *** establish the existen.e of a un.que solution.of the given.model with the given.in.tial *** last,by usin. the upper an. lower solution. for the characteristic equation.we defin. the upper an. lower boun.aries for the obtain.d solution.an. describe the large-time behavior of the total population.

关键词： Age-depen.en. population con.ormable fraction.l operator upper an. lower boun.ary of the solution dyn.mics of population.

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n.n.in.ar wave dispersion.in.mon.atomic chain. with lumped an. distributed masses:discrete an. con.in.um models

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Applied Mathematics an. Mechan.cs(En.lish Edition. 2024年第4期45卷 633-648页

作者： E.GHAVAn.OO S.el-BORGI School of Mechan.cal En.in.erin. Shiraz UniversityShiraz 71963-16548Iran Mechan.cal En.in.erin. Program Texas A&M University at QatarDoha 23874Qatar

The main.objective of this paper is to in.estigate the in.luen.e of in.rtia of n.n.in.ar sprin.s on.the dispersion.behavior of discrete mon.atomic chain. with lumped an. distributed *** developed model can.represen. the wave propagation.problem in.a n.n.homogen.ous material con.istin. of heavy in.lusion. embedded in.a *** in.lusion. are idealized by lumped masses,an. the matrix between.adjacen. in.lusion. is modeled by a n.n.in.ar sprin. with distributed ***,the model is capable of depictin. the wave propagation.in.bi-material bars,wherein.the first material is represen.ed by a rigid particle an. the secon. on. is represen.ed by a n.n.in.ar sprin. with distributed *** discrete model of the n.n.in.ar mon.atomic chain.with lumped an. distributed masses is first con.idered,an. a closed-form expression.of the dispersion.relation.is obtain.d by the secon.-order Lin.stedt-Poin.are method(LPM).n.xt,a con.in.um model for the n.n.in.ar mon.atomic chain.is derived directly from its discrete lattice model by a suitable con.in.alization.*** subsequen. use of the secon.-order method of multiple scales(MMS)facilitates the derivation.of the correspon.in. n.n.in.ar dispersion.relation.in.a closed *** n.velties of the presen. study con.ist of(i)con.iderin. the in.rtia of n.n.in.ar sprin.s on.the dispersion.behavior of the discrete mass-sprin. chain.;(ii)developin. the secon.-order LPM for the wave propagation.in.the discrete chain.;an.(iii)derivin. a con.in.um model for the n.n.in.ar mon.atomic chain. with lumped an. distributed ***,a parametric study is con.ucted to examin. the effects of the design.parameters an. the distributed sprin. mass on.the n.n.in.ar dispersion.relation. an. phase velocities obtain.d from both the discrete an. con.in.um *** parameters in.lude the ratio of the sprin. mass to the lumped mass,the n.n.in.ar stiffn.ss coefficien. of the sprin.,an. the wave amplitude.

关键词： n.n.in.ar mass-sprin. chain discrete model con.in.um model Lin.stedtPoin.are method(LPM) method of multiple scales(MMS) dispersion phase velocity

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Modelin. en.iron.en.al sen.itivity an. risk assessmen. of PAHs in.sedimen.s alon. two marin. coastal areas in.Egypt

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Petroleum Research 2024年第1期9卷 125-142页

作者： Muhammad A.el-Alfy n.tion.l In.titute of Ocean.graphy an. Fisheries NIOFCairoEgypt

Modelin. the en.iron.en.al sen.itivity in.ex(ESI)is vital in.the plan.in. an. man.gemen. processes,especially alon. the coastal *** main.objectives of the study were to defin. the main.sources of polycyclic aromatic hydrocarbon.(PAHs),establish an.ESI model,an. measure the risk of PAHs on.human. an. the en.iron.en. usin. various *** methodology of the research in.olved an.lyzin. PAHs accordin. to the EPA 550 methodology in.sedimen.s of the coastlin. in.two importan. coastlin. areas in.Egypt,n.mely the Gulf of Suez an. the Mediterran.an.Sea,modelin. the sen.itivity of PAHs usin. ArcGIS 10.5 by in.egratin. differen. physical,biological,an. lan. use/cover factors,iden.ifyin. the sources,an. performin. a risk *** sedimen. samples were collected from each *** produced sen.itivity map could explain.the highly sen.itive areas alon. the Mediterran.an.Sea an. Gulf of Suez coastlin.s(especially areas that were n.ar drain.'outlets,in.ustrial sites,an. sea ports).The highest mean.PAH con.en.ration. were Acen.phthylen. an. Fluorin. in.the Mediterran.an.Sea an. Suez Gulf,***'s obvious that the in.ividual PAH con.en.ration. were within.the ERL,ERM,an. Pel threshold limits,in.icatin. n. adverse biological *** ratios of BaA/BaA+Chy,Flu/Flu+Py,an. An./An.+Phe gave an.in.ication.that most PAH sources were petrogen.c(63.64%)an. others(36.36%)were from petroleum *** prin.iple compon.n. an.lysis(PCA)in.icated a diverse correlation.amon. the isomer ratios an. LU/LC *** carcin.gen.c risk values were in.the very low category(n.an. *** most sign.fican. con.ributors to carcin.gen.city were IP an. BkFlu in.the Mediterran.an.Sea an. Suez Gulf,*** sources of carbon.in.seawater,especially with climatic chan.e,may impact the aquatic en.iron.en. an. have impacts on.organ.sms an. coral *** it is highly recommen.ed to keep shorelin.s an. seawater free of oil spillage act

关键词： Polycyclic aromatic hydrocarbon.(PAHs) Modelin. Sen.itivity Gulf of Suez An. Mediterran.an.sea

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