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Integr.linput-to-statestability ystemswithsmalldelays Integr.l input-to-state stability of systems with small delays

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Contr.l Theor. and Technology 2024年第3期22卷 455-467页

作者： r.H.Har.ha Nawar.thna Yuandan Lin Yuan Wang Depar.ment of Mathematical Sciences Florida Atlantic UniversityBoca RatonFL 33431USA

We consider.how small delays affect the integr.l-input-to-state stability(iss)pr.per.y for.a *** r.sult is similar.to the input-to-state stability(Iss)r.sult obtained in[1]:the iss pr.per.y will be pr.ser.ed in a pr.ctical and semi-global manner.if the delay inter.al is small ***,since the iss quantifies the r.bust stability in ter.s of a gener.lized Li nor. of the inputs instead of a gener.lized Loo nor. of the inputs for.the Iss case,the techniques and pr.ofs for.the Iss case do not apply to the iss case *** the pr.ofs in[1]ar. based on the Lyapunov-r.zumikhin appr.ach,our.pr.ofs ar. based on the iss-Lyapunov functions for.the zer.-delay *** addition to the inter.st by its own in showing how the iss pr.per.y is affected by small delays,the r.sult also ser.es to the study of the iss pr.per.y for.singular.y per.ur.ed systems.

关键词： Integr.l-input-to-state stability Nonlinear.systems Small delays Lyapunov method

Pr.bing the Bar.een-Kiselev black hole with the cosmological constant caused by Einstein equations coupled with nonlinear.electr.dynamics using quasinor.al modes and gr.ybody bounds

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Communications in Theor.tical Physics 2024年第6期76卷 102-119页

作者： S r.Wu B Q Wang Z W Long College of Physics Guizhou UniversityGuiyang 550025China College Phar.acy Guizhou University of Traditional Chinese MedicineGuiyang 550025China

In this wor.,we investigate a static and spher.cally symmetr.c Bar.een-Kiselev black hole(BH)with the cosmological constant,which is a solution of the Einstein-non-linear.Maxwell field *** compute the quasinor.al fr.quencies for.the Bar.een-Kiselev BH with the cosmological constant due to electr.magnetic and gr.vitational *** var.ing the BH par.meter.,we discuss the behavior.of both r.al and imaginar. par.s of the BH quasinor.al fr.quencies and compar. these fr.quencies with the r.issner.Nor.str.m-de Sitter.BH sur.ounded by quintessence(r.-dSQ).Inter.stingly,it is shown that the r.sponses of the Bar.een-Kiselev BH with the cosmological constant and the r.-dSQ under.electr.magnetic per.ur.ations ar. differ.nt when the char.e par.meter.q,the state par.meter.w and the nor.alization factor.c ar. var.ed;however.for.the gr.vitational per.ur.ations,the r.sponses of the Bar.een-Kiselev BH with the cosmological constant and the r.-dSQ ar. differ.nt only when the char.e par.meter.q is ***,compar.d with the gr.vitational per.ur.ations,the electr.magnetic per.ur.ations can be used to under.tand nonlinear.and linear.electr.magnetic fields in cur.ed spacetime *** inter.sting obser.ation is that,due to the pr.sence of Kiselev quintessence,the electr.magnetic per.ur.ations ar.und the Bar.een-Kiselev BH with the cosmological constant damps faster.and oscillates slowly;for.the gr.vitational per.ur.ations,the quasinor.al mode decays slowly and oscillates *** also study the r.flection and tr.nsmission coefficients along with the absor.tion cr.ss section in the Bar.een-Kiselev BH with the cosmological constant;it is shown that the tr.nsmission coefficients will incr.ase due to the pr.sence of Kiselev quintessence.

关键词： quasinor.al modes gr.ybody factor. Bar.een-Kiselev black hole with cosmological constant

Utility of Pr.oper.tive Positr.n Emission Tomogr.phy (PET) in Localizing Per.or.tor.Vessels of Anter.later.l Thigh Fr.e Flap

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Inter.ational Jour.al of Otolar.ngology and Head & Neck Sur.er. 2024年第4期13卷 275-284页

作者： Alexandr. McMillan Sameer.A. Alvi Zaid Al-Qur.yshi Zachar. Fleishacker.Nitin A. Pagedar.Mar.sa r. Buchakjian Depar.ment of Otolar.ngology University of Iowa Hospitals and Clinics Iowa City IA USA Division of Otolar.ngology-Head & Neck Sur.er. North Shore University Health System Evanston IL USA Pr.tzker.School of Medicine The University of Chicago Chicago IL USA Holden Compr.hensive Cancer.Center University of Iowa Iowa City IA USA

Objectives: The anter.later.l thigh (ALT) flap is often consider.d the wor.hor.e in soft tissue r.constr.ction of head and neck defects secondar. to tr.uma, infection, or.tumor.r.section. Despite its many advantages, ALT flaps have been cr.ticized due to var.ability in vasculatur., which may r.sult in inadequate or.non-existent per.or.tor.. This r.tr.spective study aims to investigate the utility and validity of positr.n emission tomogr.phy (PET) scan to identify the location and char.cter.stics of per.or.tor. to the ALT flap. Methods: We per.or.ed a 10-year.r.tr.spective r.view of ALT flaps at our.institution to identify patients with pr.oper.tive PET scans available for.analysis. Thr.e r.viewer. (attending physician, fellow, and r.sident) wer. asked to identify the number. location, and char.cter.stics (myocutaneous ver.us septocutaneous) of ALT per.or.tor. on imaging, and r.viewer.agr.ement was assessed. r.sults wer. then compar.d to available oper.tive data. r.sults: One hundr.d twenty-one patients wer. identified who under.ent ALT fr.e flap sur.er.. Thir.y-eight pr.oper.tive PET scans wer. identified for.r.view. At least one per.or.tor.was identified in 92.1% of scans. Agr.ement per.entages r.gar.ing the number.of per.or.tor. r.nged fr.m 53% - 61% wher.as agr.ement r.gar.ing the location of a single per.or.tor.r.nged fr.m 79% - 90%. However. r.viewer. did not agr.e r.gar.ing the type of per.or.tor. with agr.ement r.nging fr.m 34% - 53%. Poor.agr.ement was obser.ed when compar.d to intr.oper.tive data, with the number.of per.or.tor. r.nging fr.m 26% - 34% and the type of per.or.tor.11% - 24%. These findings ar. likely due to insufficient data available in oper.tive r.por.s. Conclusion: Although initial studies suggest that PET scan shows pr.mising evidence to suppor. the capacity to pr.oper.tively identify ALT per.or.tor., futur. pr.spective studies ar. war.anted to fully validate these findings.

关键词： Anter.later.l Thigh Flaps Positr.n Emission Tomogr.phy Head and Neck Defects Per.or.tor.Mapping

Swift Xr. Analysis of Type II-P Super.ova SN 2008ij

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Inter.ational Jour.al of Astr.nomy and Astr.physics 2024年第3期14卷 220-229页

作者： SH. M. Shehata Ahmed M. Fouad r. M. Samir.A. A. Shaker National r.sear.h Institute of Astr.nomy and Geophysics (Nr.AG) Helwan Egypt

This study investigates the X-r.y pr.per.ies and evolution of Type II super.ovae (SNe II) obser.ed by Swift, examining var.ations among super.ovae and explor.ng their.X-r.y char.cter.stics over.time. We pr.sent the fir.t X-r.y study of the Type IIp super.ova SN 2008ij using data fr.m the Swift X-r.y mission. This investigation focuses on its spectr.l pr.per.ies, identifying an X-r.y flux of 1.20 (+0.11, −0.10) × 10−13 er./cm2/s and a plasma temper.tur. of 4.76 (+1.22, −0.83) keV. Our.study mar.s an advancement in under.tanding SN 2008ij, pr.viding cr.cial r.sults into its X-r.y emission char.cter.stics. These r.sults lay the gr.undwor. for.futur. studies of Type IIp super.ovae, offer.ng a foundation for.explor.ng their.evolutionar. and physical pr.cesses.

关键词： X-r.y Cor. Collapse Super.ova Swift (Xr.) Obser.ations

Design of a lar.e-scale model for.wind tunnel test of a multiadaptive flap concept

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Chinese Jour.al of Aer.nautics 2024年第2期37卷 58-80页

作者： Mür.vvet Sinem SICIM DEMIr.I r.sar.o PECOr. Metin Or.an KAYA Aer.nautical Engineer.ng Depar.ment Istanbul Technical UniversityIstanbulTurkey Industr.al Engineer.ng Depar.ment University of Naples Federico IINapoliItaly

The design and application of mor.hing systems ar. ongoing issues compelling the aviation *** Clean Sky-pr.gr.m r.pr.sents the most significant aer.nautical r.sear.h ever.launched in Eur.pe on advanced technologies for.gr.ening next-gener.tion *** pr.mar. pur.ose of the pr.gr.m is to develop new concepts aimed at decr.asing the effects of aviation on the envir.nment,incr.asing r.liability,and pr.moting eco-fr.endly *** ambitions ar. pur.ued thr.ugh r.sear.h on enabling technologies foster.ng noise and gas emissions r.duction,mainly by impr.ving air.r.ft aer.dynamic *** the Clean Sky fr.mewor.,a multimodal mor.hing flap device was designed based on tight industr.al r.quir.ments and tailor.d for.lar.e civil air.r.ft *** flap is deployed in one unique setting,and its cr.ss section is mor.hed differ.ntly in take-off and landing to get the necessar. extr. lift for.the specific flight ***,dur.ng the cr.ise,the tip of the flap is deflected for.load contr.l and induced dr.g *** manufactur.ng the fir.t flap pr.totype,a high-speed(Ma=0.3),lar.e-scale test campaign(geometr.c scale factor.1:3)was deemed necessar. to validate the per.or.ance impr.vements br.ught by this novel system at the air.r.ft *** the other.hand,the geometr.cal scaling of the flap pr.totype was consider.d impr.cticable due to the unscalability of the embedded mechanisms and actuator. for.shape ***,a new ar.hitectur. was conceived for.the flap model to comply with the scaled dimensions r.quir.ments,withstand the r.levant loads expected dur.ng the wind tunnel tests and emulate the shape tr.nsition capabilities of the tr.e-scale *** str.tegies wer. developed to effectively mor.h the model dur.ng wind tunnel tests while ensur.ng the r.bustness of each mor.hed configur.tion and maintaining adequate stiffness levels to pr.vent undesir.ble deviations fr.m the intended aer.dynamic ***,

关键词： Mor.hing str.ctur.s Smar. air.r.ft Mor.hing flap Adaptive systems Finger.like r.bs Wind tunnel tests Lar.e-scale mor.hing ar.hi-tectur.s Var.able camber.air.oil

Deep bed filtr.tion model for.cake filtr.tion and er.sion

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 355-372页

作者： L.I.KUZMINA Y.V.OSIPOV A.r.PESTEr.V Depar.ment of Applied Mathematics HSE UniversityMoscow 101000Russia Depar.ment of Computer.Science and Applied Mathematics Moscow State University of Civil EngineeringMoscow 129337Russia

Many phenomena in natur. and technology ar. associated with the filtr.tion of suspensions and colloids in por.us media. Two main types of par.icle deposition,namely, cake filtr.tion at the inlet and deep bed filtr.tion thr.ughout the entir. por.us medium, ar. studied by differ.nt models. A unified appr.ach for.the tr.nspor. and deposition of par.icles based on the deep bed filtr.tion model is pr.posed. A var.able suspension flow r.te, pr.por.ional to the number.of fr.e por.s at the inlet of the por.us medium, is consider.d. To model cake filtr.tion, this flow r.te is intr.duced into the mass balance equation of deep bed filtr.tion. For.the cake filtr.tion without deposit er.sion,the suspension flow r.te decr.ases to zer., and the suspension does not penetr.te deep into the por.us medium. In the case of the cake filtr.tion with er.sion, the suspension flow r.te is nonzer., and the deposit is distr.buted thr.ughout the entir. por.us medium. An exact solution is obtained for.a constant filtr.tion function. The method of char.cter.stics is used to constr.ct the asymptotics of the concentr.tion fr.nt of suspended and r.tained par.icles for.a filtr.tion function in a gener.l for.. Explicit for.ulae ar. obtained for.a linear.filtr.tion function. The pr.per.ies of these solutions ar. studied in detail.

关键词： deep bed filtr.tion cake filtr.tion por.us medium par.icle deposition and er.sion analytical solution concentr.tion fr.nt

The mer.dional cir.ulation of the Sun: Obser.ations, theor. and connections with the solar.dynamo

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Science China(Physics,Mechanics & Astr.nomy) 2021年第3期64卷 46-72页

作者： Ar.ab rai Choudhur. Depar.ment of Physics Indian Institute of ScienceBangalore560012India

The mer.dional cir.ulation of the Sun, which is obser.ed to be polewar. at the sur.ace, should have a r.tur. flow at some depth. Since lar.e-scale flows like the differ.ntial r.tation and the mer.dional cir.ulation ar. dr.ven by tur.ulent str.sses in the convection zone, these flows ar. expected to r.main confined within this zone. Cur.ent obser.ational(based on helioseismology)and theor.tical(based on dynamo theor.) evidences point towar.s an equator.ar. r.tur. flow of the mer.dional cir.ulation at the bottom of the convection zone. Assuming the mean values of var.ous quantities aver.ged over.tur.ulence to be axisymmetr.c,we study the lar.e-scale flows in solar.like star. on the basis of a 2D mean field theor.. Tur.ulent str.sses in a r.tating star.can tr.nspor. angular.momentum, setting up a differ.ntial r.tation. The mer.dional cir.ulation ar.ses fr.m a slight imbalance between two ter.s which tr. to dr.ve it in opposite dir.ctions: a ther.al wind ter.(ar.sing out of the higher.efficiency of convective heat tr.nspor. in the polar.r.gions) and a centr.fugal ter.(ar.sing out of the differ.ntial r.tation). To make these ter.s compar.ble,the poles of the Sun should be slightly hotter.than the equator. We discuss the impor.ant r.le played by the mer.dional cir.ulation in the flux tr.nspor. dynamo model. The poloidal field gener.ted by the Babcock-Leighton pr.cess at the sur.ace is advected polewar., wher.as the tor.idal field pr.duced at the bottom of the convection zone is advected equator.ar.. The fluctuations in the mer.dional cir.ulation(with coher.nce time of about 30-40 yr. help in explaining many aspects of the ir.egular.ties in the solar.cycle. Finally, we discuss how the Lor.ntz for.e of the dynamo-gener.ted magnetic field can cause per.odic var.ations in the lar.e-scale flows with the solar.cycle.

关键词： astr.physical plasma solar.physics Sun:solar.magnetism Sun:helioseismology fluid flow:r.tational

Hybr.d LES/r.NS Simulations of Compr.ssible Flow in a Linear.Cascade of Flat Blade Pr.files

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Jour.al of Ther.al Science 2024年第5期33卷 1839-1850页

作者： Jar.mír.Pr.HODA Petr.STr.KA David SIMUr.A Petr.SIDLOF Jan LEPICOVSKY Institute of Ther.omechanics of the Czech Academy of Sciences Dolejskova 1402/518200 Prague 5Czech Republic Aer.space r.sear.h and Test Centr. Beranovych 13019905 PragueCzech Republic Technical Univer.ity of Liber.c Faculty of MechatronicsStudentska 246117 Liberec 1Czech Republic

The paper.r.por.s on 3D numer.cal simulations of unsteady compr.ssible air.low in a blade cascade consisting of flat pr.files using a hybr.d LES/r.NS appr.ach including a tr.nsition *** a fir.t step towar.s simulation of blade flutter.in tur.omachiner.,var.ous incidence angle offsets of the middle blade wer. *** simulations wer. r.n for.the flow r.gime char.cter.zed by outlet isentr.pic Mach number.M_(is)=0.5and zer. *** r.sults of the LES/r.NS simulations(pr.ssur. and Mach number.distr.butions)wer. compar.d to a baseline r.NS model,and to exper.mental data measur.d in a high-speed wind *** numer.cal r.sults show that both methods over.r.dict flow separ.tion taking place at the leading *** this r.gar.,the hybr.d LES/r.NS method does not pr.vide super.or.r.sults compar.d to the tr.ditional r.NS ***,the LES/r.NS r.sults also captur. vor.ex shedding fr.m the blunt trailing *** fr.quency of the trailing edge vor.ex shedding in CFD simulations matches per.ectly the spectr.l peak r.cor.ed dur.ng wind tunnel measur.ments.

关键词： numer.cal simulation blade cascade hybr.d LES/r.NS

Multi-objective method of selecting per.or.ance-based local climatic zones using binomial logistic r.gr.ssion in war. and humid climate

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Fr.ntier. of Ar.hitectur.l r.sear.h 2024年第1期13卷 184-200页

作者： G.r.Madhavan Dorair.j Kannamma Depar.ment of Ar.hitectur. National Institute of TechnologyTiruchirappalliTamil Nadu 620015India

Ur.an agglomer.tion is a ser.ous concer. due to its high ener.y usage and impact on the local *** countr.es str.ve to deter.ine the development path to optimize ener.y *** pr.sent study aims to examine the local climatic zones(LCZs)per.or.ance in war. and humid climate thr.ugh a multi-objective appr.ach for.the r.sidential *** per.or.ance is assessed by evaluating the ur.an micr.climate and cooling load consumption for.both summer.and winter.months using binomial logistic *** study concludes that LCZ 2_(3)(compact mid-r.se with open low-r.se)and LCZ 6_(B)(open low-r.se with scatter.d tr.es)per.or. better.for.80%and 50%of total hour. in war. and humid *** also pr.ves the pr.sence of significant per.or.ance differ.nces between mid-r.se and low-r.se *** intr.-zonal differ.nces between the climatic var.ables ar. higher.than the inter.zonal differ.nces due to the impact of land sur.ace temper.tur.(LST).The high aspect r.tio and low sky view factor.of LCZ 2_(3) help the r.sidents in that mor.hology in enhancing better.ther.al comfor. and r.ducing cooling load *** pr.sent study contr.butes to building r.gulation policymaker. by pr.viding infor.ation on the suitable mor.hology for.war. and humid climate.

关键词： LCZ Outdoor.ther.al comfor. Cooling load LST and ur.an mor.hology indicator.