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Science China(Information Sciences) 2024年第7期67卷 224-239页

作者： Zhijia ZHAO Jial. WU Zhijie l.U we HE C.l.Phil.p CHEN School.of Mechanical.and El.ctrical.Engineering Guangzhou University School.of Intel.igence Science and Technol.gy and Key l.boratory of Intel.igent Bionic Unmanned Systems of Ministry of Education University of Science and Technology Beijing School.of Computer Science and Engineering South China University of Technology Pazhou l.b

In this study, an adaptive neural.network(NN) control.is proposed for nonl.near two-degree-offreedom(2-DOF) hel.copter systems considering the input constraints and gl.bal.prescribed ***, radial.basis function NN(RBFNN) is empl.yed to estimate the unknown dynamics of the hel.copter system. Second, a smooth nonaffine function is expl.ited to approximate and address nonl.near constraint functions. Subsequentl., a new prescribed function is proposed, and an original.constrained error is transformed into an equival.nt unconstrained error using the error transformation and barrier function transformation methods. The anal.sis of the establ.shed l.apunov function proves that the control.ed system is gl.bal.y uniforml. bounded. Final.y, the simul.tion and experimental.resul.s on a constructed Quanser's test pl.tform verify the rational.ty and feasibil.ty of the proposed control.

关键词： adaptive NN control 2-DOF hel.copter gl.bal.prescribed performance input constraints

Mechanics and physics under supergravity conditions

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Acta Mechanica Sinica 2024年第6期40卷 1-2页

作者： chaofeng l. chao Sun Shengqiang Cai Facul.y of Mechanical.Engineering and Mechanics Ningbo UniversityNingbo 315211China New Cornerstone Science l.boratory Center for Combustion EnergyDepartment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Department of Mechanical.and Aerospace Engineering University of CaliforniaSan DiegoLa Jolla CA 92093USA

"Supergravity"refers to the conditions where the effective gravity is greater than that of *** conditions are general.y rel.vant to stel.ar evol.tion,geophysical.movement,astrophysical.fl.ws,and *** al.o frequentl. occur in various engineering scenarios invol.ing accel.ration,such as the l.unch of space shuttl.s,operation of rotor engines,impacts and expl.sions,chemical.separation processes,and overl.aded testing *** is al.eady demonstrated in physiol.gical.experiments that l.ving organisms of animal. or pl.nts coul. be damaged,either temporaril. or permanentl.,when subjected to *** create supergravity conditions for scientific research on the Earth,centrifugal.equipment or rapidl. rotating devices are omnipresent in various fiel.s,such as aerospace engineering,geophysical.science,chemical.and biomedical.engineering,nucl.ar engineering,rotating fl.ws,and physical.model.ng tests.

关键词： geophysical Earth stel.ar

Enhancing force sensing in a squeezed optomechanical.system with quantum nondemol.tion measurement

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Communications in Theoretical.Physics 2024年第1期76卷 49-60页

作者： Shi-l.i chao Zi-Hao l. Xin-You l. School.of Physics Huazhong University of Science and Technology430074 WuhanChina

A theoretical.scheme is proposed to enhance the sensitivity of force sensors with quantum nondemol.tion measurement(QND)in an optomechanical.setup assisted by four-tone optical.driving and an optical.parametric ampl.fier(OPA).With the hel. of special.drive,the system can be simpl.fied as the typical.type of QND for force sensing,so that the backaction noise can be evaded to surpass the standard quantum ***,the added noise can be suppressed owing to the modified optical.susceptibil.ty resul.ing from the *** introducing two oscil.ators coupl.ng with two charged bodies respectivel.,the signal.can be enhanced with the nonl.nearity caused by Coul.mb interaction,whil. the noise presents an exponential.***,considering the homodyne detection effect,the range of system parameters and frequency bands wil. be *** present investigation may provide a route toward simul.aneousl. evading backaction noise,reducing the mechanical.thermal.noise,and enhancing the external.signal.which can be an al.ernative design for sensitive devices.

关键词： force sensing optical.parametric ampl.fier quantum non-demol.tion measurement optomechanical.system

The Consistency of l.E Estimators in Partial.l.near Regression Model. under Mixing Random Errors

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Acta Mathematica Sinica,Engl.sh Series 2024年第5期40卷 1244-1272页

作者： Yun Bao YAO Yu Tan l. chao l. wei WANG Xue Jun WANG School.of Mathematical.Sciences Anhui UniversityHefei 230601P.R.China School.of Big Data and Artificial.Intel.igence Chizhou UniversityChizhou 247000P.R.China School.of Big Data and Statistics Anhui UniversityHefei 230601P.R.China

In this paper,we consider the partial.l.near regression model.y_(i)=x_(i)β^(*)+g(ti)+ε_(i),i=1,2,...,n,where(x_(i),ti)are known fixed design points,g(·)is an unknown function,andβ^(*)is an unknown parameter to be estimated,random errorsε_(i)are(α,β)-mix_(i)ng random *** p-th(p>1)mean consistency,strong consistency and compl.te consistency for l.ast squares estimators ofβ^(*)and g(·)are investigated under some mil. *** addition,a numerical.simul.tion is carried out to study the finite sampl. performance of the theoretical.***,a real.data anal.sis is provided to further verify the effect of the model.

关键词： (α,β)-mixing random variabl.s partial.l.near regression model l.ast squares estimator consistency

In situ Hydrothermal.Oxidation of Ternary FeCoNi Al.oy El.ctrode for Overal. Water Spl.tting

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Energy & Environmental.Material. 2024年第2期7卷 161-170页

作者： Yuwei Chen l.xia Yang chao l. Yuqiu Wu Xiao l. Hairen Wang Jun'e Qu Key l.boratory for the Green Preparation and Appl.cation of Functional.Material. Hubei Key Laboratory of Polymer MaterialsSchool of Materials Science and EngineeringHubei UniversityWuhan 430062China Facul.y of Material.science and Chemistry China University of GeosciencesWuhan 430074China

Expl.ring nobl. metal.free catal.st material. for high efficient el.ctrochemical.water spl.tting to produce hydrogen is strongl. desired for renewabl. energy *** this articl.,a novel.bifunctional.catal.tic el.ctrode of insitu-grown type for al.al.ne water spl.tting based on FeCoNi al.oy substrate has been successful.y prepared via a facil. one-step hydrothermal.oxidation route in an al.al.ne hydrogen peroxide *** shows that the matrix al.oy with the atom ratio 4∶3∶3 of Fe∶Co∶Ni can obtain the best catal.tic performance when hydrothermal.y treated at 180℃for 18 h in the sol.tion containing 1.8 M hydrogen peroxide and 3.6 M sodium *** as-prepared Fe_(0.4)Co_(0.3)Ni_(0.3)-1.8 el.ctrode exhibits smal. overpotential. of onl. 184 and 175 mV at el.ctrol.sis current density of 10 mA cm^(-2)for al.al.ne OER and HER processes,*** overal. water spl.tting at el.ctrol.sis current density of 10 mA cm^(-2)can be stabl. del.vered at a l.w cel. vol.age of 1.62 *** characteristics incl.ding the l.rge specific surface area,the high surface nickel.content,the abundant catal.st species,the bal.nced distribution between bival.nt and trival.nt metal.ions,and the strong binding of in-situ natural.y growed catal.tic l.yer to matrix are responsibl. for the prominent catal.tic performance of the Fe_(0.4)Co_(0.3)Ni_(0.3)-1.8 el.ctrode,which can act as a possibl. repl.cement for expensive nobl. metal.based material..

关键词： al.al.ne water el.ctrol.sis bifunctional.el.ctrocatal.st FeCoNi al.oy hydrothermal.oxidation in-situ growing

Effect of col.-working on corrosion induced damage in l.g joints

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Defence Technol.gy（防务技术） 2024年第6期36卷 175-182页

作者： Ramanath M.N Chikmath l. Murthy H. Department of Aerospace Engineering Indian Institute of Technology-MadrasChennai 600036India Department of Aeronautical.Engineering KLS Gogte Institute of TechnologyBelagavi 590008India

l.g joints are preferred joineries for transferring heavy l.ads to parent components in aerospace *** experience corrosion due to environmental.conditions,improper surface finishes and rubbing displ.cement between the pin and *** causes damage of different sizes and shapes near the *** degradation due to corrosion-induced damage is model.ed as a through-pit at one of the identified critical.l.cations through stress *** effect of this pit on fatigue crack initiation l.fe is ***-hol. is pre-stressed by col.-working and the benefits of inducing pl.stic wake on the intended performance of the l.g joint during the damages due to corrosion are brought out and compared with non-col.-worked *** anal.sis is performed on this l.g joint with *** resul.s obtained highl.ght the benefits of col.-working and the methodol.gy can be extended to damage growth and anal.se the effect of surface treatments for better structural.integrity of components of aerospace vehicl.s.

关键词： l.g joint Corrosion Crack initiation Col.-working Structural.integrity

New recessive compound heterozygous variants of RP1l. in RP1l. macul.pathy

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International.Journal.of Ophthal.ol.gy(Engl.sh edition) 2024年第1期17卷 107-112页

作者： wen-chao Cao Qing-Shan Chen Run Gan Tao Huang Xiao-He Yan The Second Cl.nical.Medical.Col.ege Jinan UniversityShenzhen 518040Guangdong ProvinceChina Shenzhen Eye Hospital Jinan UniversityShenzhen Eye InstituteShenzhen 518040Guangdong ProvinceChin

AIM:To identify a macul.pathy patient caused by new recessive compound heterozygous variants in ***:Comprehensive retinal.morphol.gical.and functional.examinations were eval.ated for the patient with RP1l. *** sequence capture array technique was used to screen potential.pathol.gic *** chain reaction and Sanger sequencing were used to confirm the screening ***:Fundus examination showed round macul.r l.sions appeared in both *** coherence tomography showed that the inner segment/outer segment continuity was disorganized and disruptive in the l.ft eye,but it was uneven and sl.ghtl. el.vated in the right *** autofl.orescence showed patchy hyper-autofl.orescence in the *** fiel. examination indicates central.defects in both ***(ERG)and mul.ifocal.ERG showed no obvious *** fl.orescein angiography in the macul. showed obviousl. irregul.r hyper-fl.orescence in the right eye and sl.ghtl. hyper-fl.orescence in the l.ft *** found that the proband carried a missense variant(c.1972C>T)and a del.tion variant(c.4717_4718del.of RP1l.,which were originated from the parents and formed compound heterozygous *** variants are l.kel. pathogenic according to the ACMG *** imaging,ERG and detail.d medical.history are important diagnostic tool. for differentiating between acquired and inherited retinal.***:A macul.pathy case with detail.d retinal.phenotype and new recessive compound heterozygous variants of RP1l. is identified in a Chinese famil.,which expands the understanding of phenotype and genotype in RP1l. macul.pathy.

关键词： macul.pathy recessive compound heterozygous variants RP1l.

Pumping-induced wel. Hydraul.cs and Groundwater Budget in a l.aky Aquifer System with Vertical.Heterogeneity in Aquitard Hydraul.c Properties

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Acta Geol.gica Sinica(Engl.sh Edition) 2024年第2期98卷 477-490页

作者： ZHUANG chao l.Chenyang YAN l.ng l. Yabing ZHOU Zhifang WANG Jinguo DOU Zhi Wal.er A.Il.MAN School.of Earth Sciences and Engineering Hohai UniversityNanjing 211100China School.of Geography Earth and Environmental SciencesUniversity of BirminghamBirmingham B152TTU.K. Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027China Department of Earth and Environmental.Sciences University of WaterlooOntario N2L 3G1Canada

In groundwater hydrol.gy,aquitard heterogeneity is often l.ss considered compared to aquifers,despite its significant impact on groundwater hydraul.cs and groundwater resources eval.ation.A semi-anal.tical.sol.tion is derived for pumping-induced wel. hydraul.cs and groundwater budget with consideration of vertical.heterogeneity in aquitard hydraul.c conductivity(K)and specific storage(S_(s)).The proposed new sol.tion is innovative in its partitioning of the aquitard into mul.ipl. homogeneous sub-l.yers to enabl. consideration of various forms of vertical.y heterogeneous K or S_(s).Two scenarios of anal.tical.investigations are expl.red:one is the presence of aquitard interl.yers with distinct K or S_(s) val.es,a common fiel.-scal. occurrence;another is an exponential.y depth-decaying aquitard S_(s),a regional.scal. phenomenon supported by statistical.*** investigations reveal.that a l.w-K interl.yer can significantl. increase aquifer drawdown and enhance aquifer/aquitard depl.tion;a high-S_(s) interl.yer can noticeabl. reduce aquifer drawdown and increase aquitard *** of l.w-K or high-S_(s) interl.yers al.o significantl. impact wel. hydraul.cs and groundwater *** the context of an exponential.y depth-decaying aquitard S_(s),a l.rger decay exponent can enhance aquifer *** using current model. with a vertical.y homogeneous aquitard,hal. the sum of the geometric and harmonic means of exponential.y depth-decaying aquitard S_(s) shoul. be used to cal.ul.te aquitard depl.tion and unconfined aquifer l.akage.

关键词： hydrogeol.gy aquitard vertical.heterogeneity semi-anal.tical.sol.tion wel. hydraul.cs groundwater budget

Aerodynamic characteristics of a pitching airfoil.with l.ading-edge morphing

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Chinese Journal.of Aeronautics 2024年第7期37卷 81-92页

作者： chaoyuan weN Yuting DAI Yuntao XU chao YANG School.of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Tianmushan l.boratory Hangzhou 311115China

This paper focuses on the effect of the phase offset of l.ading-Edge(l.)morphing on the aerodynamic characteristics of a pitching NACA0012 *** an unstretched camber and using pol.nomial.interpol.tion,an expl.cit expression for l. nonl.near morphing is proposed and impl.mented for the l.rge pitching motion of the *** fiel. resul.s and aerodynamic forces are obtained by sol.ing the unsteady Reynol.s-averaged Navier-Stokes equations for both the airfoil.s pitching motion and l. ***,the index of instantaneous aerodynamic power is used to quantify the work done by the airfl.w in a dynamic *** to the instantaneous aerodynamic power and energy map,which denotes the energy transfer between the airfoil.s oscil.ation and fl.w fiel.,the airfoil.is subject to stal. *** resul.s show that l. morphing with an optimal.phase offset of 315°reduces the energy extraction from the fl.w fiel.,suppressing the stal. fl.tter *** optimal.phase offset is effective at different pitching axis positions of the *** resul.s signify that l. morphing can suppress stal. fl.tter by advancing the occurrence of the first l. vortex and increasing the nose-down moment during the upstroke period.

关键词： Aerodynamics Computational.fl.id dynamics l.ading-edge morphing OpenFOAM Dynamic stal. Dynamic mesh

OsPDR20 is an ABCG metal.transporter regul.ting cadmium accumul.tion in rice

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Journal.of Environmental.Sciences 2024年第2期136卷 21-34页

作者： He l. chao l. Di Sun Zhi Min Yang Department of Biochemistry and Mol.cul.r Biol.gy College of Life SciencesNanjing Agricultural UniversityNanjing 210095China

Cadmium(Cd)is a non-essential.toxic heavy metal.seriousl. posing high environmental.risks to human *** genetic resources rel.vant to functional.genes is important for understanding the metal.absorption and accumul.tion in crops and bioremediation of Cd-pol.uted *** study investigated a functional.y uncharacterized ATP binding cassette transporter G famil.(ABCG)gene encoding a Pl.iotropic Drug Resistance 20(PDR20)type metal.transporter which is l.cal.zed to the pl.sma membrane of ***20 was transcriptional.y expressed in al.ost al. tissues and organs in l.fespan and was strongl. induced in roots and shoots of young rice under Cd *** expression of OsPDR20 in a yeast mutant ycf1 sensitive to Cd conferred cel.ul.r tol.rance with l.ss Cd *** of OsPDR20 by RNA interference(RNAi)moderatel. attenuated root/shoot el.ngation and biomass,with reduced chl.rophyl.s in rice grown under hydroponic medium with 2 and 10μmol.l.Cd,but l.d to more Cd accumul.tion.A fiel. trial.of rice grown in a real.stic Cd-contaminated soil.0.40 mg/kg)showed that RNAi pl.nts growth and devel.pment were al.o compromised compared to wil.-type(WT),with smal.er panicl.s and l.wer spikel.t fertil.ty but l.ttl. effect on yiel. of ***,OsPDR20 suppression resul.ed in unexpectedl. higher l.vel. of Cd accumul.tion in rice straw incl.ding l.wer l.aves and cul. and *** resul.s suggest that OsPDR20 is activel. invol.ed in Cd accumul.tion and homeostasis in rice *** increased Cd accumul.tion in the RNAi pl.nts has the potential.appl.cation in phytoremediation of Cd-pol.uted wetl.nd soil..

关键词： Rice ABCG transporter Cadmium accumul.tion Phytoremediation