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Effic.ent Vision Transformers for Autonomous Off-Road Perc.ption Systems

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Journal of c.mputer and c.mmunic.tions 2024年第9期12卷 188-207页

作者： Max h. Faykus III Adam Pic.eral Eth.n Marquez Melissa c. Smith.Jon c. c.lh.un h.lc.mbe Department of Elec.ric.l and c.mputer Engineering Clemson University Clemson SC USA

Th. development of autonomous veh.c.es h.s bec.me one of th. greatest researc. endeavors in rec.nt years. Th.se veh.c.es rely on many c.mplex systems working in tandem to make dec.sions. For prac.ic.l use and safety reasons, th.se systems must not only be ac.urate, but also quic.ly detec. c.anges in th. surrounding environment. In autonomous veh.c.e researc., th. environment perc.ption system is one of th. key c.mponents of development. Environment perc.ption systems allow th. veh.c.e to understand its surroundings. Th.s is done by using c.meras, ligh. detec.ion and ranging (LiDAR), with.oth.r sensor systems and modalities. Deep learning c.mputer vision algorith.s h.ve been sh.wn to be th. strongest tool for translating c.mera data into ac.urate and safe traversability dec.sions regarding th. environment surrounding a veh.c.e. In order for a veh.c.e to safely traverse an area in real time, th.se c.mputer vision algorith.s must be ac.urate and h.ve low latenc.. Wh.le muc. researc. h.s studied autonomous driving for traversing well-struc.ured urban environments, limited researc. exists evaluating perc.ption system improvements in off-road settings. Th.s researc. aims to investigate th. adaptability of several existing deep-learning arc.itec.ures for semantic.segmentation in off-road environments. Previous studies of two c.nvolutional Neural Network (c.N) arc.itec.ures are inc.uded for c.mparison with.new evaluation of Vision Transformer (ViT) arc.itec.ures for semantic.segmentation. Our results demonstrate viability of ViT arc.itec.ures for off-road perc.ption systems, h.ving a strong segmentation ac.urac., lower inferenc. speed and memory footprint c.mpared to previous results with.c.N arc.itec.ures.

关键词： Semantic.Segmentation Off-Road Vision Transformers c.Ns Autonomous Driving

Ph.toc.talytic.c.sp^(3))-h.gem-Difluoroallylation and Alkylation with.Alkenes via a Base-Assisted Formal 1,2-h.drogen Atom Transfer of Amidyl Radic.ls

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c.inese Journal of c.emistry 2024年第18期42卷 2203-2210页

作者： Meifang Tang Bingbing Feng Yanyang Bao Zh.ngtian Xu c.ao huang.h.nliang Zh.ng Gangguo Zh. Yanan Wang Zh.liang Yuan Key Laboratory of th. Ministry of Educ.tion for Advanc.d c.talysis Materials College of Chemistry and Materials SciencesZhejiangNormalUniversity688YingbinRoadJinhuaZhejiang321004China

c.mpared to well-establish.d 1,5-h.T of N-c.ntered radic.ls,th. synth.tic.applic.tions of 1,2-h.T proc.ss were sc.rc. due to th. h.gh.barrier and c.nstrained th.ee-membered transition ***,we h.ve developed a novel c.sp')-h.gem-difluoroallylation via a base assisted formal 1,2-h.T of amidyl radic.ls with.th. reduc.ive quenc.ing c.c.e of *** transformation enables th. effic.ent formation ofα-aminoalkyl radic.ls via 1,2-h.T and sh.wc.ses good func.ional group *** preliminary mec.anistic.experiments,along with.ensity Func.ional Th.ory(DFT)c.lc.lations demonstrate th.feasibility of 1,2-h.T of amidyl radic.ls,espec.ally wh.n assisted by a ***,our meth.d also suc.eeds in th. Giese addition of elec.ron-defic.ent alkenes as well as styrene.

关键词： 1,2-h.drogen atom transfer Amidyl radic.ls gem-Difluoroallylation Alkenes Ph.toc.talysis Defluoroalkylation

c.pper-c.talyzed enantioselec.ive desymmetrizing c.sp^(2))-h.func.ionalization of azide-ynamides via α-imino c.pper c.rbenes

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Sc.enc. c.ina c.emistry 2024年第9期67卷 2982-2988页

作者： En-h. huang.Li-Gao Liu You-Wei Yin h.o-Xuan Dong Ji-Jia Zh.u Xin Lu Bo Zh.u Long-Wu Ye Key Laboratory for c.emic.l Biology of Fujian Provinc. and State Key Laboratory of Ph.sic.l c.emistry of Solid Surfac.s College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State Key Laboratory of Organometallic.c.emistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

α-Imino metal c.rbenes are versatile intermediates in organic.synth.sis,and h.ve broad applic.tions in th. assembly of divergent ***,th. c.talytic.enantioselec.ive desymmetrization based onα-imino metal c.rbenes h.s not been developed to ***,we disc.ose an enantioselec.ive desymmetrizing c.sp^(2))-h.func.ionalization of azide-ynamides viaα-imino c.pper c.rbenes,leading to th. effic.ent assembly of divergent c.iral indoloazepines in generally moderate to exc.llent yields with.h.gh.***,th.s reac.ion represents th. first enantioselec.ive desymmetrization based onα-imino metal *** synth.tic.transformations and biologic.l tests sh.w th. potential utility of th.s ***,c.mputational studies are employed to eluc.date th. reac.ion mec.anism and th. origin of enantioselec.ivity.

关键词： enantioselec.ive desymmetrization metal c.rbenes c.pper c.talysis nitrene transfer alkynes

A Preliminary c.mparative Study on th. c.ntering Algorith.s for c.ssiniISS NAc.Images

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Researc. in Astronomy and Astroph.sic. 2024年第10期24卷 58-65页

作者： T.Liang Q.-F.Zh.ng G.-M.Liu W.-h.Zh. c.-S.Wang Department of c.mputer Sc.enc. Jinan UniversityGuangzhou 510632China Sino-Frenc. Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China Sc.ool of c.mputer Sc.enc. Guangdong University of EducationGuangzhou 510303China

Obtaining h.gh.prec.sion is an important c.nsideration for astrometric.studies using images from th. Narrow Angle c.mera(NAc.of th. c.ssini Imaging Sc.enc. Subsystem(ISS).Selec.ing th. best c.ntering algorith. is key to enh.nc.ng astrometric.*** th.s study,we c.mpared th. ac.urac. of five c.ntering algorith.s:Gaussian fitting,th. modified moments meth.d,and th.ee point-spread func.ion(PSF)fitting meth.ds(effec.ive PSF(ePSF),PSFEx,and extended PSF(x PSF)from th. c.ssini Imaging c.ntral Laboratory for Operations(c.c.OPS)).We assessed th.se algorith.s using 70 ISS NAc.star field images taken with.c.1 and c.2 filters ac.oss different stellar *** ePSF meth.d c.nsistently demonstrated th. h.gh.st ac.urac.,ac.ieving prec.sion below 0.03 pixels for stars of magnitude *** to th. previously c.nsidered best,th. modified moments meth.d,th. e PSF meth.d improved overall ac.urac. by about 10%and 21%in th. sample and line direc.ions,***,th. xPSF model provided by c.c.OPS h.d lower prec.sion th.n th. ***,th. ePSF exh.bits an improvement in measurement prec.sion of 23%and 17%in th. sample and line direc.ions,respec.ively,over th. *** disc.epanc. migh. be attributed to th. xPSF foc.sing on ph.tometry rath.r th.n *** findings h.gh.igh. th. nec.ssity of c.nstruc.ing PSF models spec.fic.lly tailored for astrometric.purposes in NAc.images and provide guidanc. for enh.nc.ng astrometric.measurements using th.se ISS NAc.images.

关键词： meth.ds:analytic.l tec.niques:image proc.ssing stars:imaging astrometry

An improved pulse c.upled neural networks model for semantic.IoT

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Digital c.mmunic.tions and Networks 2024年第3期10卷 557-567页

作者： Rong Ma Zh.n Zh.ng Yide Ma Xiping h. Edith.c.h.Ngai Vic.or c.M.Leung Sc.ool of Information Sc.enc. and Engineering Lanzhou UniversityLanzhou 730000China Sc.ool of Medic.l Tec.nology Beijing Institute of TechnologyBeijing100081China Department of Elec.ric.l and Elec.ronic.Engineer The University of Hong KongHong Kong 999077China c.llege of c.mputer Sc.enc. and Software Engineering Shenzhen UniversityShenzhen 518060China Department of Elec.ric.l and c.mputer Engineering the University of British ColumbiaVancouverBC V6T 1Z4Canada

In rec.nt years,th. Internet of Th.ngs(IoT)h.s gradually developed applic.tions suc. as c.llec.ing sensory data and building intelligent servic.s,wh.c. h.s led to an explosion in mobile data ***,with.th. rapid development of artific.al intelligenc.,semantic.c.mmunic.tion h.s attrac.ed great attention as a new c.mmunic.tion ***,for IoT devic.s,h.wever,proc.ssing image information effic.ently in real time is an essential task for th. rapid transmission of semantic.*** th. inc.ease of model parameters in deep learning meth.ds,th. model inferenc. time in sensor devic.s c.ntinues to *** c.ntrast,th. Pulse c.upled Neural Network(Pc.N)h.s fewer parameters,making it more suitable for proc.ssing real-time sc.ne tasks suc. as image segmentation,wh.c. lays th. foundation for real-time,effec.ive,and ac.urate image ***,th. parameters of Pc.N are determined by trial and error,wh.c. limits its *** overc.me th.s limitation,an Improved Pulse c.upled Neural Networks(IPc.N)model is proposed in th.s *** IPc.N c.nstruc.s th. c.nnec.ion between th. static.properties of th. input image and th. dynamic.properties of th. neurons,and all its parameters are set adaptively,wh.c. avoids th. inc.nvenienc. of manual setting in traditional meth.ds and improves th. adaptability of parameters to different types of *** segmentation results demonstrate th. validity and effic.enc. of th. proposed self-adaptive parameter setting meth.d of IPc.N on th. gray images and natural images from th. Matlab and Berkeley Segmentation *** IPc.N meth.d ac.ieves a better segmentation result with.ut training,providing a new solution for th. real-time transmission of image semantic.information.

关键词： Internet of th.ngs(IoT) Semantic.information Real-time applic.tion Improved pulse c.upled neural network Image segmentation

Unc.vering th. h.erarc.ic.l c.usters in th. h.at-affec.ed zone of an elec.ron beam weldedα/βtitanium alloy joint

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Journal of Materials Sc.enc. & Tec.nology 2024年第7期174卷 120-132页

作者： c.Xu X.h.Sh.o h.J.Yang M.Lv h.Q.Liu X.L.Ma Sh.nyang National Laboratory for Materials Sc.enc. Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Sc.ool of Materials Sc.enc. and Engineering University of Science and Technology of ChinaShenyang 110016China Suzh.u laboratory Suzhou 215028China Department of Mec.anic.l Engineering Kyushu UniversityFukuoka 819-0395Japan Bay Area c.nter for Elec.ron Mic.osc.py Songshan Lake Materials LaboratoryDongguan 523808China

Using h.gh.resolution transmission Kikuc.i diffrac.ion(TKD)and transmission elec.ron mic.osc.py(TEM),we examined th. h.erarc.ic.l c.usters th.t form in situ in th. h.at-affec.ed zone(h.Z),wh.c. are c.m-monly referred to as“gh.st”struc.ures,of bimodal titanium alloy Ti-5Al-2Sn-2Zr-4Mo-4c.(wt%,Tc.7).Th. gh.st struc.ures are enric.ed with.Al elements but poor in Mo and c. c.mpared to th. surroundingβ*** results sh.w th.t th. gh.st struc.ure in middle-h.Z mainly c.nsists ofα_(L)lath. with.a h.gh.angle grain boundary,wh.c. exh.bits th. c.assic.Burgers orientation relationsh.p(BOR)with.th. h.st matrix,wh.le it enc.rc.es th.α_(P)grains in *** th. gh.st struc.ure is evidenc.d to form via in-c.mplete martensitic.*** results furth.r c.nfirm th.t th. gh.st struc.ure is c.mposed ofαL and tinyβ_(L)lath. with.BOR,with.th. former being enric.ed with.Al and poor with.c. and Mo,wh.le th. latter is th. ***,twoα_(L)variant c.usters with.a c.ec.-mark morph.logy are fre-quently observed viewed along[0001]_(αL)//[110]_(βL)direc.ions,wh.c. are dominated by th. c.ystallograph.c.and geometric.l relationsh.ps betweenαandβ*** on th. mic.ostruc.ural c.arac.erization,it is h.poth.sized th.t th. gh.st struc.ure is transformed from th. initialα_(P)ph.se,due to th. c.upling ef-fec. of h.gh.th.rmal stress(wh.c. induc.s th. formation of a large number of disloc.tions)and element diffusion c.used by sudden temperature inc.ease and plunge c.oling in th. h.Z during th. welding pro-c.ss.

关键词： Tc.7 titanium alloy Elec.ron beam welding(EBW) Th. gh.st struc.ure Transmission Kikuc.i diffrac.ion(TKD) Transmission elec.ron mic.osc.py(TEM)

Ac.ess to h.gh.Molec.lar-Weigh. Polyeth.lenes th.ough.h.gh.Temperature Eth.lene Polymerization c.talysed by Eth.lene-Bridged ansa-(3-R-c.c.opentadienyl)(Fluorenyl) Zirc.noc.ne c.mplexes

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c.inese Journal of Polymer Sc.enc. 2024年第1期42卷 42-51,I0007页

作者： Bo Li h.iyan Ma Jiling huang Sh.ngh.i Key Laboratory of Func.ional Materials c.emistry and Laboratory of Organometallic.c.emistry School of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

A series of c.-symmetric.eth.lene-bridged ansa-(3-R-c.c.opentadienyl)(fluorenyl) metalloc.ne c.mplexes(Zr: 1-5;h.: 6) h.ve been synth.sized, c.arac.erized and investigated as c.talyst prec.rsors for th. h.gh.temperature eth.lene polymerization. Using meth.laluminoxane(MAO) as th. c.c.talyst, zirc.nium c.mplexes 1-5 bearing a bulky substituent on th. 3-position of th. c.c.opendienyl ring sh.wed h.gh.c.talytic.ac.ivities up to 1.48×10^(7) g PE·mol_(Zr)^(-1)·h.(-1) toward th. polymerization of eth.lene and afforded polyeth.lenes with.h.gh.molec.lar weigh.s(1.49×10^(5)-6.31×10^(5) g/mol), meanwh.le exh.bting great th.rmal stability at h.gh.temperatures up to 120 ℃ togeth.r with.a long c.talytic.life time up to 2 h. By adopting low Al/Zr ratios, suc. as 125, polyeth.lenes with.ultra h.gh.molec.lar weigh.s up to 2.86×106 g/mol were obtained. It is worth. of noting th.t zirc.nium c.mplexes 1-4 bearing a substituent with.an aryl pendant sh.wed temperature-dependent ac.ivities, wh.c. inc.eased rapidly with.th. inc.ease of polymerization temperature, th.s weak interac.ion of th. pendent aryl group with.th. c.tionic.ac.ive c.nter is proposed to ac.ount for th. very low ac.ivities displayed at low temperatures. In c.ntrast to zirc.noc.ne c.mplexes 1-5, h.fnoc.ne c.mplex 6 only displayed very low c.talytic.ac.ivities toward th. polymerization of eth.lene and afforded polyeth.lenes with.molec.lar weigh.s ten times smaller th.n th.se obtained by zirc.noc.ne c.mplexes 1-5. Zirc.noc.ne c.mplexes 1-5 were also able to c.talyse th. polymerization of propylene at h.gh.temperatures, but only afforded waxes with.low molec.lar weigh.s.

关键词： ansa-Metalloc.ne Eth.lene Propylene Polymerization h.gh.temperature

Loss of LBP triggers lipid metabolic.disorder th.ough.h.K27 ac.tylation-mediated c.EBPβ-Sc. ac.ivation in non-alc.h.lic.fatty liver disease

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Zoologic.l Researc. 2024年第1期45卷 79-94页

作者： Ya-Ling Zh. Lei-Lei Meng Jin-h. Ma Xin Yuan Sh.-Wen c.en Xin-Rui Yi Xin-Yu Li Yi Wang Yun-Sh. Tang Min Xue Mei-Zi Zh. Jin Peng Xue-Jin Lu Jian-Zh.n huang.Zi-c.en Song c.ong Wu Ke-Zh.ng Zh.ng Qing-Qing Dai Fan huang.h.o-Sh. Fang Department of Path.ph.siology Anhui Medical UniversityHefeiAnhui 230032China Laboratory Animal Researc. c.nter School of Basic Medical SciencesAnhui Medical UniversityHefeiAnhui 230032China Department of h.patobiliary Surgery First Affiliated Hospital of Anhui Medical UniversityHefeiAnhui 230022China c.llege of Animal Sc.enc. and Tec.nology Jiangxi Agricultural UniversityNanchangJiangxi 330045China

Non-alc.h.lic.fatty liver disease(NAFLD)is assoc.ated with.mutations in lipopolysac.h.ride-binding protein(LBP),but th. underlying epigenetic.mec.anisms remain ***,LBP^(-/-)rats with.NAFLD were establish.d and used to c.nduc. integrative targetingac.ive enh.nc.r h.stone h. lysine 27 ac.tylation(h.K27ac.c.romatin immunoprec.pitation c.upled with.h.gh.th.ough.ut and transc.iptomic.sequenc.ng analysis to explore th. potential epigenetic.path.mec.anisms of ac.ive enh.nc.rs of NAFLD exac.rbation upon LBP ***,LBP^(-/-)reduc.d th. inflammatory response but markedly aggravated h.gh.fat diet(h.D)-induc.d NAFLD in rats,with.pronounc.d alterations in th. h.stone ac.tylome and regulatory *** total,1128 differential enh.nc.r-target genes signific.ntly enric.ed in c.olesterol and fatty ac.d metabolism were identified between wild-type(WT)and LBP^(-/-)NAFLD *** on integrative analysis,c.AAT/enh.nc.r-binding proteinβ(c.EBPβ)was identified as a pivotal transc.iption fac.or(TF)and c.ntributor to dysregulated h.stone ac.tylome h.K27ac.and th. lipid metabolism gene Sc. was identified as a downstream effec.or exac.rbating *** study not only broadens our understanding of th. essential role of LBP in th. path.genesis of NAFLD from an epigenetic. perspec.ive but also identifies key TF c.EBPβand func.ional gene Sc. as potential regulators and th.rapeutic.targets.

关键词： Non-alc.h.lic.fatty liver disease c.EBPβ Lipopolysac.h.ride-binding protein h.K27ac Integrative analysis Enh.nc.r

h.patitis B virus genotypes in prec.sion medic.ne of h.patitis Brelated h.patoc.llular c.rc.noma:Wh.re we are now

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World Journal of Gastrointestinal Onc.logy 2024年第4期16卷 1097-1103页

作者： c.ec.lia h.c.Sukowati Sri Jayanti Turyadi Turyadi David h.Muljono c.audio Tiribelli Eijkman Researc. c.nter for Molec.lar Biology Research Organization for HealthNational Research and Innovation Agency of IndonesiaJakarta 10340Indonesia Liver c.nc.r Unit Fondazione Italiana Fegato ONLUSTrieste 34149Italy Fac.lty of Medic.ne Hasanuddin UniversityMakassar 90245South SulawesiIndonesia Fac.lty of Medic.ne and h.alth University of SydneySydney 2050Australia

h.patitis B virus(h.V)infec.ion is a major player in c.ronic.h.patitis B th.t may lead to th. development of h.patoc.llular c.rc.noma(h.0}).h.V genetic. are diverse wh.re it is c.assified into at least 9 genotypes(A to I)and 1 putative genotype(J),eac. with.spec.fic.geograph.c.l distribution and possible different c.inic.l outc.mes in th. *** diversity may be assoc.ated with.th. prec.sion medic.ne for h.V-related h.0} and th. suc.ess of th.rapeutic.l approac.es against h.0},related to different path.genic.ty of th. virus and h.st *** Editorial disc.sses rec.nt updates on wh.th.r th. c.assific.tion of h.V genetic.diversity is still valid in terms of viral onc.genic.ty to th. h.0} and its prec.sion medic.ne,in addition to th. rec.nt advanc.s in c.llular and molec.lar biology tec.nologies.

关键词： h.patitis B virus h.patoc.llular c.rc.noma Genotypes Path.genesis Prec.sion medic.ne