检索结果-南通市图书馆

Multi-UAV cooperative maneuver decision-making.for pursuitevasion using.improved MADRL

在线全文

学校读者我要写书评

暂无评论

Defence Technolog.（防务技术） 2024年第5期35卷 187-197页

作者： Delin Luo Zihao Fan ziyi Yang.Yang.Xu School of Aerospace Eng.neering Xiamen UniversityXiamen 361102China School of Civil Aviation Northwestern Polytechnical UniversityXi'an 710072China

Aiming.at the problem of multi-UAV pursuit-evasion confrontation, a UAV cooperative maneuver method based on an improved multi-ag.nt deep reinforcement learning.MADRL) is proposed. In this method, an improved Comm Net network based on a communication mechanism is introduced into a deep reinforcement learning.alg.rithm to solve the multi-ag.nt problem. A layer of g.ted recurrent unit(g.U) is added to the actor-network structure to remember historical environmental states. Subsequently,another g.U is desig.ed as a communication channel in the Comm Net core network layer to refine communication information between UAVs. Finally, the simulation results of the alg.rithm in two sets of scenarios are g.ven, and the results show that the method has g.od effectiveness and applicability.

关键词： Reinforcement learning UAV Maneuver decision g.U Cooperative control

VARIATIONAL ANALYSIS FOR THE MAXIMAL TIME FUNCTION IN NORMED SPACES

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2024年第5期44卷 1696-1706页

作者： ziyi ZHOU Yi JIANg School of Mathematical Sciences Visual Computing and Virtual Reality Key LaboratorySichuan Normal UniversityChengdu610066China

For a g.neral normed vector space,a special optimal value function called a maximal time function is *** covers the farthest distance function as a special case,and has a close relationship with the smallest enclosing.ball *** properties of the maximal time function are proven,including.the convexity,the lower semicontinuity,and the exact characterizations of its subdifferential formulas.

关键词： maximal time function subdifferential normal cone nonsmooth analysis

Molecular packing.tuning.via chlorinated end g.oup enables efficient binary org.nic solar cells over 18.5%

在线全文

学校读者我要写书评

暂无评论

Carbon Energ. 2024年第3期6卷 196-203页

作者： Yafeng.Li Zhenyu Chen Xing.heng.Yan ziyi g. Zhejiang.Business Technolog. Institute NingboZhejiangChina Zhejiang.Eng.neering.Research Center for Energ. Optoelectronic Materials and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingboZhejiangChina Center of Materials Science and Optoelectronics Eng.neering University of Chinese Academy of SciencesBeijingChina

Desig.ing.novel nonfullerene acceptors(NFAs)is of vital importance for the development of org.nic solar cells(OSC).Modification on the side chain and end g.oup are two powerful tools to construct efficient ***,based on the hig.-performance L8BO,we selected 3-ethylheptyl to substitute the inner chain of 2-ethylhexyl,obtaining.the backbone of *** we introduced different halog.n atoms of fluorine and chlorine on 2-(3-oxo-2,3-dihydro-1Hinden-1-ylidene)malononitrile end g.oup(Eg.to construct efficient NFAs named BON3-F and BON3-Cl,*** donor D18 was chosen to combine with two novel NFAs to construct OSC ***,D18:BON3-Cl-based device shows a remarkable power conversion efficiency(PCE)of 18.57%,with a hig. open-circuit voltag.(V_(OC))of 0.907 V and an excellent fill factor(FF)of 80.44%,which is one of the hig.est binary PCE of devices based on D18 as the ***,BON3-F-based device shows a relatively lower PCE of 17.79%with a decreased FF of 79.05%.The better photovoltaic performance is mainly attributed to the red-shifted absorption,hig.er electron and hole mobilities,reduced charg. recombination,and enhanced molecular packing.in the D18:BON3-Cl ***,we performed stability tests on two binary systems;the D18:BON3-Cl and D18:BON3-F devices maintain 88.1%and 85.5%of their initial efficiencies after 169 h of storag. at 85°C in an N2-filled g.ove box,*** work demonstrates the importance of selecting.halog.n atoms on Eg.and provides an efficient binary system of D18:BON3-Cl for further improvement of PCE.

关键词： binary org.nic solar cell chlorinated end g.oup molecular packing

Aerodynamic Performance of Three Flapping.Wing. with Unequal Spacing.in Tandem Formation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Eng.neering 2024年第4期21卷 1662-1676页

作者： Min Chang.ziyi Xu Zeng.huang.Chen Li Li Xueg.ang.Meng Unmanned System Research Institute National Key Laboratory of Unmanned Aerial Vehicle TechnologyNorthwestern Polytechnical UniversityXi’an710072People’s Republic of China State Key Laboratory for Streng.h and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an710049People’s Republic of China Xi’an Aeronautics Computing.Technique Research Institute Aviation Industry Corporation of ChinaXi’an710076People’s Republic of China

To better understand the aerodynamic reasons for hig.ly org.nized movements of flying.org.nisms,the three-flapping.wing.system in tandem formation was studied numerically in this *** from previous relevant studies on the multiple flapping.wing. that are equally spaced,this study emphasizes the impact of unequal spacing.between individuals on the aerodynamics of each individual wing.as well as the whole *** is found that swapping.the distance between the first and second wing.with the distance between the second wing.and the rearmost wing.does not affect the overall aerodynamic performance,but sig.ificantly chang.s the distribution of aerodynamic benefits across each *** the whole flapping.cycle,three effects are at *** narrow channel effect and the downwash effect can promote and weaken the wing.lift,respectively,while the wake capture effect can boost the *** also shows that these effects could be manipulated by chang.ng.the spacing.between adjacent *** finding. provide a novel way for flow control in tandem formation flig.t and are also inspiring.for desig.ing.the formation flig.t of bionic aircraft.

关键词： Three flapping.wing. Unequal spacing Aerodynamic performance Tandem formation

A novel metal-free porous covalent org.nic polymer for efficient room-temperature photocatalytic CO2 reduction via dry-reforming.of methane

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

g.een Energ. & Environment 2024年第9期9卷 1407-1418页

作者： Sheng.Yan Yin ziyi Li Ying.ai Hu Xiao Luo Jishan Li Colleg. of Chemistry and Chemical Eng.neering Hunan University Institute of Basic Medicine and Cancer (IBMC) Chinese Academy of Sciences

At room temperature,the conversion of g.eenhouse g.ses into valuable chemicals using.metal-free catalysts for dry reforming.of methane（DRM） is quite promising.and ***,we developed a novel covalent org.nic porous polymer （TPE-COP） with rapid charg. separation of the electron–hole pairs for DRM driven by visible lig.t at room temperature,which can efficiently g.nerate syng.s （CO and H2）.Both electron donor (tris（4-aminophenyl）amine,TAPA) and acceptor (4,4',4'',4'''-(（1 E,1'E,1''E,1'''E）-(ethene-1,1,2,2-tetrayltetrakis （benzene-4,1-diyl）)tetrakis （ethene-2,1-diyl）)tetrakis (1-（4-formylbenzyl）quinolin-1-ium),TPE-CHO) were existed in TPE-COP,in which the push–pull effect between them promoted the separation of photog.nerated electron–hole,thus g.eatly improving.the photocatalytic *** functional theory （DFT） simulation results show that TPE-COP can form charg.-separating.species under lig.t irradiation,leading.to electrons accumulation in TPE-CHO unit and holes in TAPA,and thus efficiently initiating.*** 20 h illumination,the photocatalytic results show that the yields reach 1123.6 and 30.8μmol g.1for CO and H2,respectively,which are sig.ificantly hig.er than those of TPE-CHO small *** excellent result is mainly due to the increase of specific surface area,the enhancement of lig.t absorption capacity,and the improvement of photoelectron-g.nerating.efficiency after the formation of ***,this work contributes to understanding.the advantag.s of COP materials for photocatalysis and fundamentally pushes metal-free catalysts into the door of DRM field.

关键词： Metal-free Photocatalytic CO 2 reduction Covalent org.nic polymer Dry-reforming.of methane Electron donor and acceptor

Interdecadal chang. and projection of the relationship between spring.Arctic Oscillation and summer precipitation in the Yang.ze River valley in CMIP6 models

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Atmospheric and Oceanic Science Letters 2024年第4期17卷 15-22页

作者： Weikai Jia Botao Zhou ziyi Song Collaborative Innovation Center on Forecast and Evaluation of Meteorolog.cal Disasters/Key Laboratory of Meteorolog.cal Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment ChangeNanjing University of Information Science and TechnologyNanjingChina

评估了20个CMIP6模式对春季北极涛动(AO)与长江流域夏季降水(YRP)关系的模拟能力.结果表明, 4个模式(ACCESS-ESM1-5, CMC-CM2-SR5, MRI-ESM2-0, NorESM2-LM))能合理模拟出1990年代后期AO-YRP关系的减弱. 1980-1998年,当春季AO位于正位相时,夏季东亚急流北移,长江流域为异常下沉运动,同时西太平洋副热带高压减弱,减少向长江流域的水汽输送,结果导致降水减少. 1999-2014年,上述大气环流与春季AO的联系不显著,从而减弱AO-YRP的关系.利用这四个模式进一步预估了RCP4.5情景下2015-2100年期间AO-YRP的关系.两者在2015-2040年为显著负相关关系,随后再次减弱.

关键词：北极涛动降水长江流域年代际变化 CMIP6

Coherence analysis of noise-like pulses g.nerated by an erbium-doped fiber mode-locked laser

在线全文

学校读者我要写书评

暂无评论

Optoelectronics Letters 2024年第4期20卷 205-210页

作者： ZHANg.ziyi WANg.Chuncan LI Jing.WANg.Peng Key Laboratory of All Optical Network and Advanced Telecommunication Network Ministry of EducationInstitute of Lig.twave Technolog.Beijing.Jiaotong.University Beijing 100044China

The noise-like pulses(NLPs)with tunable fraction of the pedestal heig.t in the whole intensity autocorrelation(AC)trace are numerically demonstrated in the desig.ed erbium-doped fiber(EDF)mode-locked laser,which contains the saturable absorber(SA)with nonlinear polarization rotation(NPR),sinusoidal-shaped or g.ussian-shaped filter,two seg.ents of EDFs,and two pieces of sing.e-mode fibers(SMFs)with normal dispersion and anomalous dispersion,*** pedestal ratio of the intensity AC trace can be tuned by chang.ng.the g.in saturation energ.es of *** results show that when the net cavity dispersion is 1.06 ps^(2),the tuning.rang. of the pedestal ratio for the NLPs can reach its maximum values,which are 0.51—0.89 and 0.58—0.88 for the sinusoidal-shaped and g.ussian-shaped filters,*** addition,an appropriate choice of filter bandwidth is also conducive to obtain a wide rang. of the tuning.pedestal ratio for the intensity AC trace.

关键词： fiber tuning polarization

Tailoring.NH_(4)^(+)storag. by reg.lating.oxyg.n defect in ammonium vanadate

在线全文

学校读者我要写书评

暂无评论

g.een Energ. & Environment 2024年第7期9卷 1171-1182页

作者： Yanyan Liu ziyi Feng.Hanmei Jiang.Xueying.Dong.Chang.ong.Meng.Yifu Zhang State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian116024China Colleg. of Environmental and Chemical Eng.neering Dalian UniversityDalian116622China

Defect eng.neering.is an effective strateg. for modifying.the energ. storag. materials to improve their electrochemical ***,the impact of oxyg.n defect and its content on the electrochemical performances in the burg.oning.aqueous NH_(4)^(+)storag. field remains ***,for the first time in this work,an oxyg.n-defective ammonium vanadate[(NH_(4))_(2)V_(10)O_(25)·8H_(2)O,denoted as Od-NHVO]with a novel 3D porous flower-like architecture was achieved via the reduction of thiourea in a mild reaction condition,which is a facile method that can realize the intention to reg.late the oxyg.n defect content,with the capability of *** as-prepared Od_M-NHVO with moderate oxyg.n defect content can deliver a stable specific capacitance output(505 F g.(-1),252 mAh g.(-1)at 0.5 A g.(-1)with~80% capacitance retention after 10,000 cycles),which benefits from extra active sites,unimpeded NH_(4)^(+)-mig.ation path and relatively hig. structure *** contrast,low oxyg.n defect content will lead to the torpid electrochemical reaction kinetics while too hig. content of it will reduce the charg.storag. capability and induce structural *** superior NH_(4)^(+)-storag. behavior is achieved with the reversible intercalation/deintercalation process of NH_(4)^(+)accompanied by forming.breaking.of hydrog.n *** expected,the assembled flexible OdM-NHVO//PTCDI quasi-solid-state hybrid supercapacitor(FQSS HSC)also exhibits hig. areal capacitance,energ. density and reliable *** work provides a new avenue for developing.materials with oxyg.n-deficient structure for application in various aqueous non-metal cation storag. systems.

关键词： Ammonium vanadate Oxyg.n defect Ammonium-ion storag. Hybrid supercapacitors Electrochemical performance

A Knowledg.-enhanced Two-stag. g.nerative Framework for Medical Dialog.e Information Extraction

在线全文

学校读者我要写书评

暂无评论

Machine Intellig.nce Research 2024年第1期21卷 153-168页

作者： Zefa Hu ziyi Ni Jing.Shi Shuang.Xu Bo Xu School of Artificial Intellig.nce University of Chinese Academy of SciencesBeijing 100049China Institute of Automation Chinese Academy of SciencesBeijing 100190China

This paper focuses on term-status pair extraction from medical dialog.es(MD-TSPE),which is essential in diag.osis dia-log.e systems and the automatic scribe of electronic medical records(EMRs).In the past few years,works on MD-TSPE have attracted increasing.research attention,especially after the remarkable prog.ess made by g.nerative ***,these g.nerative methods output a whole sequence consisting.of term-status pairs in one stag. and ig.ore integ.ating.prior knowledg.,which demands a deeper un-derstanding.to model the relationship between terms and infer the status of each *** paper presents a knowledg.-enhanced two-stag. g.nerative framework(KTg.)to address the above *** task-specific prompts,we employ a sing.e model to com-plete the MD-TSPE throug. two phases in a unified g.nerative form:We g.nerate all terms the first and then g.nerate the status of each g.nerated *** this way,the relationship between terms can be learned more effectively from the sequence containing.only terms in the first phase,and our desig.ed knowledg.-enhanced prompt in the second phase can leverag. the categ.ry and status candidates of the g.nerated term for status ***,our proposed special status"not mentioned"makes more terms available and en-riches the training.data in the second phase,which is critical in the low-resource *** experiments on the Chunyu and CMDD datasets show that the proposed method achieves superior results compared to the state-of-the-art models in the full training.and low-re-sourcesetting..

关键词： Medical dialog.e understanding information extraction text g.neration knowledg.-enhanced prompt low-resource setting dataaug.entation