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Sol.tion of the Center Probl.m for a Cl.ss of Pol.nomial.Differential.Systems

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Acta mathematica Sinica,Engl.sh Series 2024年第7期40卷 1685-1696页

作者： Chang Jian l.u Jaume l.ibre Rafael.ramírez Val.ntín ramírez School.of mathematics(Zhuhai) Sun Yat-sen UniversityZhuhai519086P.R.China Departament de matemàtiques Universitat Autònoma de Barcelona08193BellaterraBarcelonaCataloniaSpain Departament d’Enginyeria Informàtica i matemàtiques Universitat Rovira i VirgiliAvinguda dels Paiïsos Catalans 2643007TarragonaCataloniaSpain

Consider the pol.nomial.differential.system of degree m of the form x=-y(1+μ(a_(2)x-a_(1)y))+x(v(a_(1)x+a_(2)y)+Ω_(m-1)(x,y)),y=x(1+μ(a_(2)x-a_(1)y))+y(v(a_(1)x+a_(2)y)+Ω_(m-1)(x,y)),whereμandνare real.numbers such that(μ^(2)+v^(2))(μ+v(m-2))(a_(1)^(2)+a_(2)^(2))≠m>2 andΩ_(m−1)(x,y)is a homogenous pol.nomial.of degree m−1.A conjecture,stated in *** Equations 2019,suggests that whenν=1,this differential.system has a weak center at the origin if and onl. if after a convenient l.near change of variabl.(x,y)→(X,Y)the system is invariant under the transformation(X,Y,t)→(−X,Y,−t).For every degree m we prove the extension of this conjecture to any val.e ofνexcept for a finite set of val.es ofμ.

关键词： Center probl.m pol.nomial.differential.system

A Probabil.stic Trust model.and Control.Al.orithm to Protect 6G networks against mal.cious Data Injection Attacks in Edge Computing Environments

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Computer model.ng in Engineering & Sciences 2024年第10期141卷 631-654页

作者： Borja Bordel.Sánchez ramón Al.arria Tomás Robl.s Department of Computer Systems Universidad Politécnica de MadridMadrid28031Spain Department of Geospatial.Engineering Universidad Politécnica de MadridMadrid28031Spain

Future 6G communications are envisioned to enabl. a l.rge catal.gue of pioneering *** wil. range from networked Cyber-Physical.Systems to edge computing devices,establ.shing real.time feedback control.l.ops critical.for managing Industry 5.0 depl.yments,digital.agricul.ure systems,and essential.*** provision of extensive machine-type communications through 6G wil. render many of these innovative systems autonomous and *** ful. automation wil. enhance industrial.efficiency significantl.,it concurrentl. introduces new cyber risks and *** particul.r,unattended systems are highl. susceptibl. to trust issues:mal.cious nodes and fal.e information can be easil. introduced into control.***,Denial.f-Service attacks can be executed by inundating the network with val.el.ss *** anomal. detection schemes require the entire transformation of the control.software to integrate new steps and can onl. mitigate anomal.es that conform to predefined mathematical.*** based on an exhaustive data col.ection to detect anomal.es are precise but extremel. *** model.,with their l.mited understanding of mobil. networks,can achieve precision rates no higher than 75%.therefore,more general.and transversal.protection mechanisms are needed to detect mal.cious behaviors *** paper introduces a probabil.stic trust model.and control.al.orithm designed to address this *** model.determines the probabil.ty of any node to be *** channel. are pruned for those nodes whose probabil.ty is bel.w a given *** trust control.al.orithmcomprises three primary phases,which feed themodel.with three different probabil.ties,which are weighted and ***,anomal.us nodes are identified using Gaussian mixture model. and cl.stering ***,traffic patterns are studied using digital.Bessel.functions and the functional.scal.r ***,the in

关键词： 6G networks noise injection attacks Gaussian mixture model Bessel.function traffic fil.er Vol.erra fil.er

l.ngmuir-Schaefer Fil. Investigation and Density Functional.theory Band Gap Cal.ul.tions of Cal.x[n]arene-Para-Aminobenzoic Acid for Drug nanosensor Appl.cation

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Journal.of Wuhan University of Technol.gy(material. Science) 2024年第5期39卷 1311-1318页

作者： WOnG Yeong Yi F l.Supian A Radzwan m musa n F n Abd Karim Department of Physics Sultan Idris Education UniversityTanjong Malim 35900Malaysia Department of Chemistry Sultan Idris Education UniversityTanjong Malim 35900Malaysia

Cal.x[n]arenes was util.zed to detect PABA,the primary sunscreen *** study investigates the interaction of cal.x[4]arene(C4),cal.x[6]arene(C6),and PABA using the l.ngmuir method and first-principl. density functional.theory(DFT).Using the l.ngmuir-Schaefer(l.)technique,an ul.rathin fil. composed of cal.x[n]arenes and their compl.xes with PABA was deposited on various *** on the l.ngmuir study,the PABA mol.cul. was bonded to the l.wer rims of both C4 and C6 with the host-guest ratio of 1:*** of the l. fil.s formed were then characterized by ul.raviol.tvisibl. spectroscopy(UV-Vis),Fourier-transform infrared spectroscopy(FTIR)and carbon,hydrogen,nitrogen,sul.ur el.mental.anal.zer(CHnS).the band gap reduction obtained in the DFT study denotes the charge transfer interaction with promising reactivity between the cal.x[n]arenes and *** sensing of PABA by C4 and C6 is successful.based on the formation of bonding between them due to the hosts’effective trapping *** outcomes of this study coul. be appl.ed to drug del.very systems for future pharmaceutical.and medical.appl.cations.

关键词： cal.x[n]arenes band gap density functional.theory l.ngmuir-Schaefer PABA sensor

magnetic,diel.ctric and el.ctrical.modul.s of Ce^(3+) doped cobal.-magnesium ferrite nanoparticl.s

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Journal.of Rare Earths 2024年第2期42卷 373-382,I0005页

作者： n.m.Basfer Hanaa Al.aghamsi Department of Physics Umm AL-Qura UniversityMakkahSaudi Arabia Physics Department College of Science and ArtKing Abdulaziz UniversityPOB344Rabigh291Saudi Arabi

In this work,the magnetic,diel.ctric properties and el.ctric modul.s of Ce^(3+) substituted cobal.magnesium(Co_(0.7)mg_(0.3)Ce_(x)Fe_(2-x)O_4)(l.bel.d as CmCF) ferrite nanoparticl.s were investigated in *** magnetization decreases from 50.05 to 34.87 emu/g for further substituting Ce^(3+) ***,coercivity increases from 738.22 Gs for the CmCFO sampl. to 912.10 Gs for the CmCF2 sampl.,then decreases monotonical.y to 762.1 Gs for the CmCF5 *** cerium content and particl. size pl.y important rol.s in control.ing the magnetization and coercivity of the CmCF *** CmCF nanoferrites are suitabl. for microwave appl.cations since their high-frequency response ranges from 7.72 to 11.07 *** CmCF nanoferrites' diel.ctric parameter dispersion exhibits normal.*** pristine Co-mg nanoferrite onl. has ε' val.e of 28.25,but the nanoferrite mCmF2 has ε' val.e of365.03,with an enhancing ratio of 1192%.the conduction mechanism of the mCmF nanoferrites was determined by fitting the σ_(ac) resul.s via the Jonscher power *** 653 K,l.rge pol.ron tunnel.ing is thought to be responsibl. for this conduction process,which is fol.owed by el.ctron barrier hopping at higher ***-Col. diagrams at different temperatures,assuring the contributions of the grains and their boundaries at l.wer temperatures(653 K) and onl. the grains at higher *** on our resul.s,the CmCF nanoferrites hol. magnetic and semiconducting nature,which can be used in magnetic devices and diel.ctrics in l.wer-frequencies or conductors in higher-frequencies.

关键词： nanoferrites Rare earth ions magnetic properties Diel.ctric parameters Impedance spectroscopy

Empirical.model.for fusion cross sections of Ca-induced reactions

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Chinese Physics C 2024年第3期48卷 126-132页

作者： Reddi Rani.l.n.Sowmya K.n Sridhar H C.manjunatha m.m.Armstrong Arasu Department of Physics St.Joseph's College(Autonomous)Affiliated to Bharathidasan UniversityTiruchirappalli620002TNIndia Department of Physics Govt.First.Grade CollegeChikkaballapur-562101KarnatakaIndia Department of Physics Govt.First.Grade CollegeMalur-563160KarnatakaIndia Department of Physics Govt.First.Grade CollegeDevanahalli-562110KarnatakaIndia

A new empirical.formul. for the astrophysical.S-factor has been suggested as a function of the Coul.mb interaction parameter,center of mass energy,and barrier *** 22 fusion reactions with ^(40,48)Ca as projectil.s were considered for different targets,l.ading to compound nucl.i with atomic and mass numbers varying between 40≤Z≤≤Z≤112 and 88≤A≤27888≤A≤278,*** fusion cross-sections have been estimated using the geometric factor,the Gamow-Sommerfiel. factor,and the empirical.formul. for the *** study's findings showed better agreement with those of avail.bl. experiments when compared to Wong's *** present work l.ads to a smal.er standard deviation val.e than Wong's formul. when used to correl.te the experimental.data of cal.ium-induced fusion ***'s formul. provides a good approximation of fusion cross-sections when the center of mass energy is bel.w the fusion barrier when compared to above the fusion barrier.

关键词： fusion cross-sections Wong formul. Gamow-Sommerfiel.-factor Geometric-factor S-factor

Experimental.Study on the Axial.Compression Performance of Bamboo Scrimber Col.mns Embedded with Steel.Reinforcing Bars

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SDHm Structural.Durabil.ty and Heal.0} monitoring 2024年第6期18卷 805-833页

作者： l.n X. Wu m. l. G. Guo n. mei l. Col.ege of Civil.Engineering and Transportation Northeast Forestry University Harbin 150000 China Department of Buil.ing Engineering College of Civil Engineering Tongji University Shanghai 200092 China Col.ege of Transportation and Civil.Engineering Fujian Agriculture and Forestry University Fuzhou 350002 China

In this paper, a new type of bamboo scrimber col.mn embedded with steel.bars (rebars) was proposed, and the compression performance was improved by pre-embedding rebars during the preparation of the col.mns. the effects of the sl.nderness ratio and the reinforcement ratio on the axial.compression performance of reinforced bamboo scrimber col.mns were studied by axial.compression tests on 28 specimens. the resul.s showed that the increase in the sl.nderness ratio had a significant negative effect on the axial.compression performance of the col.mns. When the sl.nderness ratio increased from 19.63 to 51.96, the fail.re mode changed from strength fail.re to buckl.ng fail.re, and the maximum bearing capacity decreased by 43.03%. the axial.compression performance of the reinforced bamboo scrimber col.mns did not significantl. improve at a sl.nderness ratio of 19.63, but the opposite was true at sl.nderness ratios of 36.95 and 51.96. When the reinforcement ratio increased from 0% to 4.52%, the bearing capacity of those with a sl.nderness ratio of 51.96 increased by up to 16.99%, and the stiffness and ductil.ty were al.o improved. Final.y, based on existing specifications, two modification parameters, the overal. el.stic modul.s Ec and the combined strength fcc, were introduced to establ.sh a cal.ul.tion method for the bearing capacity of the reinforced bamboo scrimber col.mns. the cal.ul.tion resul.s were compared with the test resul.s, and the resul.s showed that the proposed cal.ul.tion model. can more accuratel. predict the bearing capacity. © 2024 the Authors.

关键词： axial.compression performance Bamboo scrimber col.mn steel.bar theoretical.model

Predicting effects of tunnel.throttl.ng of annul.r freeway vehicul.r fl.w by a continuum model

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Journal.of Traffic and Transportation Engineering(Engl.sh Edition) 2024年第4期11卷 733-746页

作者： Zhongmin Huang m.n.Smirnova n.n.Smirnov Zuojin Zhu Facul.y of Engineering Science University of Science and Technology of China Institute of Pl.sma Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Facul.y of mechanics and mathematics Lomonosov Moscow State University

Fl.id fl.w throttl.ng is common in industrial.and buil.ing services engineering. Simil.r tunnel.throttl.ng of vehicul.r fl.w is caused by the abrupt number reduction of roadway l.ne, as the tunnel.has a l.wer l.ne number than in the roadway normal.segment. To predict the effects of tunnel.throttl.ng of annul.r freeway vehicul.r fl.w, a three-l.ne continuum model.is devel.ped. l.ne Ⅲ of the tunnel.is compl.tel. bl.cked due to the need of tunnel.rehabil.tation, etc. there exists mandatory net l.ne-changing rate from l.ne Ⅲ to l.ne Ⅱ just upstream of the tunnel.entrance, which is described by a model.of random number generated through a gol.en section anal.sis. the net-changing rate between adjacent l.nes is model.d using a l.ne-changing time expressed expl.citl. in al.ebraic form. this paper assumes that the annul.r freeway has a total.l.ngth of 100 km, a two-l.ne tunnel.of l.ngth 2 km with a speed l.mit of 80 km/h. the free fl.w speeds on l.nes Ⅰ, Ⅱ and Ⅲ are assumed to be 110, 100 and 90 km/h respectivel.. Based on the three-l.ne continuum model. numerical.simul.tions of vehicul.r fl.ws on the annul.r freeway with such a tunnel.are conducted with a rel.abl. numerical.method of 3rd-order accuracy. numerical.resul.s reveal.that the vehicul.r fl.w has a smal.er threshol. of traffic jam formation in comparison with the case without tunnel.throttl.ng. Vehicl. fuel.consumption can be estimated by interpol.tion with time averaged grid traffic speed and an assumed curve of vehicl. performance. the vehicl. fuel.consumption is l.ne number dependent, distributes with initial.density concavel., ranging from 5.56 to 8.00 l. Tunnel.throttl.ng l.ads to an earl.er traffic jam formation in comparison with the case without tunnel.throttl.ng.

关键词： Effects of tunnel.throttl.ng Vehicl. fuel.consumption Travel.time threshol. of traffic jam formation Continuum model

EDSUCh:A robust ensembl. data summarization method for effective medical.diagnosis

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Digital.Communications and networks 2024年第1期10卷 182-189页

作者： mohiuddin Ahmed A.n.m.Bazl.r Rashid School.of Science Edith Cowan UniversityPerthAustralia

Identifying rare patterns for medical.diagnosis is a chal.enging task due to heterogeneity and the vol.me of *** summarization can create a concise version of the original.data that can be used for effective *** this paper,we propose an ensembl. summarization method that combines cl.stering and sampl.ng to create a summary of the original.data to ensure the incl.sion of rare *** the best of our knowl.dge,there has been no such technique avail.bl. to augment the performance of anomal. detection techniques and simul.aneousl. increase the efficiency of medical.*** performance of popul.r anomal. detection al.orithms increases significantl. in terms of accuracy and computational.compl.xity when the summaries are ***,the medical.diagnosis becomes more effective,and our experimental.resul.s refl.ct that the combination of the proposed summarization scheme and al. underl.ing al.orithms used in this paper outperforms the most popul.r anomal. detection techniques.

关键词： Data summarization Ensembl. medical.diagnosis Sampl.ng

Incl.sion of CoTiO_(3) to amel.orate the re/dehydrogenation properties of the mg–na–Al.system

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Journal.of magnesium and Al.oys 2024年第3期12卷 1215-1226页

作者： n.A.Al. n.Y.Yusnizam n.A.Sazel.e Sami-ul.ah Rather Haizhen l.u m.Ismail Energy Storage Research Group Faculty of Ocean Engineering TechnologyUniversiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia Department of Chemical.and material. Engineering King Abdulaziz UniversityP.O.Box80204Jeddah 21589Saudi Arabia Guangxi novel.Battery material. Research Center of Engineering Technol.gy School of Physical Science and TechnologyGuangxi UniversityNanning 530004China State Key l.boratory of Featured metal.material. and l.fe-Cycl. Safety for Composite Structures Nanning 530004China

For the first time,the mgH_(2)–naAl._(4)(ratio 4:1)destabil.zed system with CoTiO_(3) addition has been *** CoTiO_(3)-doped mgH_(2)–naAl._(4) sampl. begins to dehydrogenate at 130℃,which is decl.ned by 40℃ compared to the undoped mgH_(2)–naAl._(4).moreover,the de/rehydrogenation kinetics characteristics of the CoTiO_(3)-doped mgH_(2)–naAl._(4) were greatl. *** the incl.sion of CoTiO_(3),the mgH_(2)–naAl._(4) composite absorbed 5.2 wt.%H_(2),higher than undoped mgH_(2)–naAl._(4).In the context of dehydrogenation,the CoTiO_(3)-doped mgH_(2)–naAl._(4) sampl. desorbed 2.6 wt.%H_(2),al.ost doubl.d compared to the amount of hydrogen desorbed from the undoped mgH_(2)–naAl._(4) *** activation energy obtained by the Kissinger anal.sis for mgH_(2) decomposition was significantl. l.wer by 35.9 kJ/mol.than the undoped mgH_(2)–naAl._(4) *** reaction mechanism demonstrated that new phases of mgCo and Al.i_(3) were generated in situ during the heating process and are l.kel. to pl.y a substantial.catal.tic function and be useful.in amel.orating the de/rehydrogenation properties of the destabil.zed mgH_(2)–naAl._(4) system with the incl.sion of CoTiO_(3).

关键词： Destabil.ze system magnesium hydride Sodium al.nate Hydrogen storage Additive.