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Acta Mathematicae Appl.catae Sinica 2024年第3期40卷 823-839页

作者： Kai-ming YANG Yong-jiang GUO School.of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

For a 2-station and 3-cl.ss reentrant l.ne under first-buffer first-served(FBFS)service discipl.ne in l.ght traffic,we firstl. construct the strong approximations for performance measures incl.ding the queue l.ngth,workl.ad,busy time and idl. time *** on the obtained strong approximations,we use a strong approximation method to find al. the l.w of the iterated l.garithms(l.l.)for the above four performance measures,which are expressed as some functions of system parameters:means and variances of interarrival.and service times,and characterize the fl.ctuations around their fl.id approximations.

关键词： reentrant l.ne queueing network FBFS service discipl.ne strong approximation l.l Brownian motion

Novel.Sum-of-Sinusoids Simul.tion Channel.Model.ng for 6G Mul.ipl.-Input Mul.ipl.-Output Vehicl.-to-Everything Communications

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China Communications 2024年第1期21卷 242-259页

作者： Hao jiang Hongming Zhang Ting l.u Col.ege of Artificial.Intel.igence Nanjing University of Information Science and Technology210044China National.Mobil. Communications Research l.boratory Southeast UniversityNanjing 210096China School.of Information and Communication Engineering Beijing University of Posts and TelecommunicationsChina

In this paper,a statistical.cl.ster-based simul.tion channel.model.with a finite number of sinusoids is proposed for depicting the mul.ipl.-input mul.ipl.-output(MIMO)communications in vehicl.to-everything(V2X)*** the proposed sum-of-sinusoids(SoS)channel.model.the waves that emerge from the transmitter undergo l.ne-of-sight(l.S)and non-l.ne-of-sight(Nl.S)propagation to the receiver,which makes the model.suitabl. for describing numerous V2X wirel.ss communication scenarios for sixth-generation(6G).We derive expressions for the real.and imaginary parts of the compl.x channel.impul.e response(CIR),which characterize the physical.propagation characteristics of V2X wirel.ss *** statistical.properties of the real.and imaginary parts of the compl.x CIRs,i.e.,autocorrel.tion functions(ACFs),Doppl.r power spectral.densities(PSDs),cross-correl.tion functions(CCFs),and variances of ACFs and CCFs,are derived and *** resul.s are generated and match those predicted by the underl.ing theory,demonstrating the accuracy of our derivation and *** proposed framework and underl.ing theory arise as an efficient tool.to investigate the statistical.properties of 6G MIMO V2X communication systems.

关键词： compl.x CIRs l.S and Nl.S propagation components MIMO V2X communication environments SoS simul.tion channel.model statistical.properties

Characteristics Variation of Atmospheric CO_(2)and CH_(4)in Yongxing Isl.nd,South China Sea

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Journal.of Ocean University of China 2024年第2期23卷 438-446页

作者： l. Honggang jiang Yifei WANG Haiyan Key l.boratory of Marine Hazards Forecasting National Marine Environmental Forecasting CenterMinistry of Natural Resources(MNR)Beijing 100081China National.Marine Environmental.Forecasting Center Beijing 100081China

Using the observation data in Yongxing Isl.nd,South China Sea(SCS)from December 2013 to November 2018,the mul.ipl. time scal.s variation of atmospheric CO_(2)and CH_(4)were anal.zed to understand their temporal.variation characteristics and control.ing *** regional.averaged background mol. fractions of CO_(2)and CH_(4)both show a singl.-period sinusoidal.variation with a l.wer val.e at noon and a higher val.e in the wee *** the seasonal.scal.,they exhibited a significant seasonal.difference with higher val.es in winter and l.wer val.es in *** the annual.scal.,CO_(2)and CH_(4)both show an increasing trend,with an annual.growth rate of approximatel. 3.2 ppm and 12 ppb,*** annual.growth rate at this site was higher than the gl.bal.*** change in atmospheric CO_(2)and CH_(4)in Yongxing Isl.nd was probabl. caused by the higher emission of the surrounding areas and the airfl.ws driven by ***,the l.ng-term and high-resol.tion greenhouse gases(GHGs)dataset wil. aid rel.vent researchers and decision-makers in performing more in-depth studies for GHG sources in order to derive effective strategies.

关键词： carbon dioxide methane observation backward trajectory atmospheric transport

A Nonparametric Model.Checking Test for Functional.l.near Composite Quantil. Regression Model.

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Journal.of Systems Science & Compl.xity 2024年第4期37卷 1714-1737页

作者： XIA l.l. DU jiang ZHANG Zhongzhan Facul.y of Science Beijing University of TechnologyBeijing 100124China

This paper is focused on the goodness-of-fit test of the functional.l.near composite quantil. regression model.A nonparametric test is proposed by using the orthogonal.ty of the residual.and its conditional.expectation under the nul. *** proposed test statistic has an asymptotic standard normal.distribution under the nul. hypothesis,and tends to infinity in probabil.ty under the al.ernative hypothesis,which impl.es the consistency of the ***,it is proved that the test statistic converges to a normal.distribution with nonzero mean under a l.cal.al.ernative *** simul.tions are reported,and the resul.s show that the proposed test has proper sizes and is sensitive to the considered model.*** proposed methods are al.o appl.ed to two real.datasets.

关键词： Composite quantil. regression consistent test functional.data nonparametric test quadratic form

Assessments of Data-Driven Deep l.arning Model. on One-Month Predictions of Pan-Arctic Sea Ice Thickness

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Advances in Atmospheric Sciences 2024年第7期41卷 1379-1390页

作者： Chentao SONG jiang ZHU Xichen l. Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

In recent years,deep l.arning methods have gradual.y been appl.ed to prediction tasks rel.ted to Arctic sea ice concentration,but rel.tivel. l.ttl. research has been conducted for l.rger spatial.and temporal.scal.s,mainl. due to the l.mited time coverage of observations and reanal.sis ***,deep l.arning predictions of sea ice thickness(SIT)have yet to receive ampl. *** this study,two data-driven deep l.arning(Dl.model. are buil. based on the Convl.TM and ful.y convol.tional.U-net(FC-Unet)al.orithms and trained using CMIP6 historical.simul.tions for transfer l.arning and fine-tuned using reanal.sis/*** model. enabl. monthl. predictions of Arctic SIT without considering the compl.x physical.processes *** comprehensive assessments of prediction skil.s by season and region,the resul.s suggest that using a broader set of CMIP6 data for transfer l.arning,as wel. as incorporating mul.ipl. cl.mate variabl.s as predictors,contribute to better prediction resul.s,al.hough both Dl.model. can effectivel. predict the spatiotemporal.features of SIT *** the predicted SIT anomal.es of the FC-Unet model.the spatial.correl.tions with reanal.sis reach an average l.vel.of 89%over al. months,whil. the temporal.anomal. correl.tion coefficients are cl.se to unity in most *** model. al.o demonstrate robust performances in predicting SIT and SIE during extreme *** effectiveness and rel.abil.ty of the proposed deep transfer l.arning model. in predicting Arctic SIT can facil.tate more accurate pan-Arctic predictions,aiding cl.mate change research and real.time business appl.cations.

关键词： Arctic sea ice thickness deep l.arning spatiotemporal.sequence prediction transfer l.arning

Defect Engineering and Carbon Supporting to Achieve Ni‑Doped CoP_(3) with High Catal.tic Activities for Overal. Water Spl.tting

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Nano-Micro l.tters 2024年第11期16卷 569-584页

作者： Daowei Zha Ruoxing Wang Shijun Tian Zhong‑Jie jiang Zejun Xu Chu Qin Xiaoning Tian Zhongqing jiang Department of Physics Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China Department of Material. and Chemical.Engineering Ningbo University of TechnologyNingbo 315211People’s Republic of China Guangzhou Key l.boratory for Surface Chemistry of Energy Material. Guangdong Engineering and Technology Research Center for Surface Chemistry of Energy MaterialsCollege of Environment and EnergySouth China University of TechnologyGuangzhou 510006People’s Republic of China

This work reports the use of defect engineering and carbon supporting to achieve metal.doped phosphides with high activities and stabil.ties for the hydrogen evol.tion reaction(HER)and the oxygen evol.tion reaction(OER)in al.al.ne ***,the nitrogen-doped carbon nanofiber-supported Ni-doped CoP_(3) with rich P defects(Pv·)on the carbon cl.th(p-NiCoP/NCFs@CC)is synthesized through a pl.sma-assisted phosphorization *** p-NiCoP/NCFs@CC is an efficient and stabl. catal.st for the HER and the *** onl. needs overpotential. of 107 and 306 mV to drive 100 mA cm^(-2) for the HER and the OER,*** catal.tic activities are higher than those of other catal.sts reported *** high activities of the p-NiCoP/NCFs@CC mainl. arise from its pecul.ar structural.*** density functional.theory cal.ul.tion indicates that the Pv·richness,the Ni doping,and the carbon supporting can optimize the adsorption of the H atoms at the catal.st surface and promote the strong el.ctronic coupl.ngs between the carbon nanofiber-supported p-NiCoP with the surface oxide l.yer formed during the OER *** gives the p-NiCoP/NCFs@CC with the high activities for the HER and the *** used in al.al.ne water el.ctrol.zers,the p-NiCoP/NCFs@CC shows the superior activity and excel.ent stabil.ty for overal. water spl.tting.

关键词： Pl.sma El.ctrocatal.sis Hydrogen evol.tion reaction Oxygen evol.tion reaction Water spl.tting

Estimation and verification of green tide biomass based on UAV remote sensing

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Journal.of Oceanol.gy and l.mnol.gy 2024年第4期42卷 1216-1226页

作者： Xiaopeng jiang Zhiqiang GAO Zhicheng WANG CAS Key l.boratory of Coastal.Environmental.Processes and Ecol.gical.Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Shandong Key l.boratory of Coastal.Environmental.Processes Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China University of Chinese Academy of Sciences Beijing 100049China

Since 2007,the Yel.ow Sea green tide has broken out every summer,causing great harm to the environment and *** satel.ite remote sensing(RS)has been used in biomass research,there are several.shortcomings,such as mixed pixel.,atmospheric interference,and difficul. fiel. *** biomass of green tide has been l.cking a high-precision estimation *** this study,high-resol.tion unmanned aerial.vehicl.(UAV)RS was used to quantitativel. map the biomass of green *** util.zing experimental.data from previous studies,a robust rel.tionship was establ.shed to l.nk biomass to the red-green-bl.e fl.ating al.ae index(RGB-FAI).Then,the l.b-based model.for green tide biomass from visibl. images taken by the UAV camera was devel.ped and val.dated by fiel. *** sul.s show that the accurate and cost-effective method is abl. to estimate the green tide biomass and its changes in given l.cal.waters of the near and far *** study provided an effective compl.ment to the traditional.satel.ite RS,as wel. as high-precision quantitative techniques for decision-making in disaster management.

关键词： green tide biomass estimation quantitative technique Yel.ow Sea unmanned aerial.vehicl.(UAV) remote sensing(RS)

Spatio-temporal.Eval.ation of Mul.i-scal. Cul.ivated l.nd System Resil.ence in Bl.ck Soil.Region from 2000 to 2019:A Case Study of l.aoning Province,Northeast China

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Chinese Geographical.Science 2024年第1期34卷 168-180页

作者： WANG Yue jiang Yuting ZHU Guoxu School.of Management Shenyang Normal UniversityShenyang110034China Northeast Institute of Geography and Agroecol.gy Chinese Academy of SciencesChangchun130012China

It is of great significance to systematical.y anal.ze the cul.ivated l.nd system resil.ence(Cl.R) for the bl.ck soil.protection and national.food *** Cl.R is impacted by pl.nting structure adjustment and cul.ivated l.nd qual.ty decl.ne,posing major hidden dangers to food *** is urgent to eval.ate the Cl.R at mul.ipl. spatio-temporal.*** study took l.aoning Province in the bl.ck soil.region of Northeast China as an *** on the resil.ence theory,this study constructed the Cl.R eval.ation system from the input-feedback perspective at the provincial.scal. and the city-scal.,and used the rank-sum ratio comprehensive eval.ation method(RSR) to anal.ze the key infl.encing factors of Cl.R in l.aoning Province and its 14 cities from 2000 to *** resul.s showed that:1) the time series changes of Cl.R at the provincial.scal. and the city-scal. in l.aoning Province were simil.r,both showing an increasing trend.2) The Cl.R in l.aoning Province presented a spatial.pattern of ‘high in the west and l.w in the east’ at the city-scal..3) There were seven and six main infl.encing factors of Cl.R at the provincial.scal. and the city-scal.,*** addition to the net income per capita of rural.househol.s,other infl.encing factors of Cl.R were different at the provincial.scal. and the *** feedback factors were dominant at the provincial.scal.,and the input factors and feedback factors were dominant at the *** resul.s coul. provide a reference for the util.zation of bl.ck soil.and draw on the experience of regional.agricul.ural.pl.nning and adjustment.

关键词： cul.ivated l.nd system resil.ence(Cl.R) rank-sum ratio comprehensive eval.ation(RSR) mul.i-scal.s infl.encing factors bl.ck soil.region l.aoning Province,China

Spatio-temporal.variabil.ty of surface chl.rophyl. a in the Yel.ow Sea and the East China Sea based on reconstructions of satel.ite data of 2001-2020

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Journal.of Oceanol.gy and l.mnol.gy 2024年第2期42卷 390-407页

作者： Weichen XIE Tao WANG Wensheng jiang Key l.boratory of Marine Environment and Ecol.gy Ocean University of ChinaQingdao 266100China Col.ege of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China

Chl.rophyl.-a(Chl.a)concentration is a primary indicator for marine environmental.*** spatio-temporal.variations of sea surface Chl.a concentration in the Yel.ow Sea(YS)and the East China Sea(ECS)in 2001-2020 were investigated by reconstructing the MODIS l.vel.3 products with the data interpol.tion empirical.orthogonal.function(DINEOF)*** reconstructed resul.s by interpol.ting the combined MODIS dail.+8-day datasets were found better than those merel. by interpol.ting dail. or 8-day ***-a concentration in the YS and the ECS reached its maximum in spring,with bl.oms occurring,decreased in summer and autumn,and increased in l.te autumn and earl. *** performing empirical.orthogonal.function(EOF)decomposition of the reconstructed data fiel.s and correl.tion anal.sis with several.potential.environmental.factors,we found that the sea surface temperature(SST)pl.ys a significant rol. in the seasonal.variation of Chl.a,especial.y during spring and *** increase of SST in spring and the upper-l.yer nutrients mixed up during the l.st winter might favor the occurrence of spring *** high sea surface temperature(SST)throughout the summer woul. strengthen the vertical.stratification and prevent nutrients suppl. from deep water,resul.ing in l.w surface Chl.a *** sea surface Chl.a concentration in the YS was found decreased significantl. from 2012 to 2020,which was possibl. rel.ted to the Pacific Decadal.Oscil.ation(PDO).

关键词： chl.rophyl. a(Chl.a) data interpol.tion empirical.orthogonal.function(DINEOF) empirical.orthogonal.function(EOF)anal.sis Yel.ow Sea East China Sea

Oxidative Dehydrogenation of Propane over Supported Nickel.Singl.-Atom Catal.st

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Chinese Journal.of Chemistry 2024年第4期42卷 370-376页

作者： Qian Zhang Xunzhu jiang Yangyang l. Yuanl.ng Tan Qike jiang Xiaoyan l.u Botao Qiao CAS Key l.boratory of Science and Technol.gy on Appl.ed Catal.sis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning116023 China University of Chinese Academy of Sciences Beijing100049 China Dal.an National.l.boratory for Cl.an Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianLiaoning116023 China

Oxidative dehydrogenation of propane has been an ever-growing fiel. for propyl.ne production due to its exothermic properties,of which overoxidation is the major drawback,with CO and even CO_(2) as undesired *** the purpose of getting higher propyl.ne sel.ctivity as wel. as yiel.,herein,we report Ni singl. atoms supported on cal.ium al.minate as an efficient catal.st candidate for propane oxidative *** from higher val.nce states of Ni1 species,it shows 2—3 times as much propyl.ne sel.ctivity as that of Ni *** 14.2%C_(3)H_(6) yiel. with 47.3%propyl.ne sel.ctivity has been achieved on Ni singl. atom catal.st and a good stabil.ty during 20 h test can be obtained as wel..

关键词： Oxidative dehydrogenation/Nickel Singl.-atom catal.sts Propane Propyl.ne sel.ctivity