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Seasonal Variation of the Sea Surface Temperature Growth Rate of ENSO

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Advances in Atmospheric Sciences 2024年第3期41卷 465-477页

作者： xinyi XING Xianghui FANG Da PANG Chaopeng JI Department of Atmospheric and Oceanic Sciences and Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Shanghai Frontiers Science Center of Atmosphere-Ocean Interaction Shanghai 200438China Shanghai Key Laboratory of Ocean-land-atmosphere Boundary Dynamics and Climate Change Fudan UniversityShanghai 200438China

El Ni?o–Southern Oscillation(ENSO) exhibits a distinctive phase-locking characteristic, first expressed during its onset in boreal spring, developing during summer and autumn, reaching its peak towards winter, and decaying over the next spring. Several studies have demonstrated that this feature arises as a result of seasonal variation in the growth rate of ENSO as expressed by the sea surface temperature(SST). The bias towards simulating the phase locking of ENSO by many state-of-the-art climate models is also attributed to the unrealistic depiction of the growth rate. In this study, the seasonal variation of SST growth rate in the Ni?o-3.4 region(5°S–5°N, 120°–170°W) is estimated in detail based on the mixed layer heat budget equation and recharge oscillator model during 1981–2020. It is suggested that the consideration of a variable mixed layer depth is essential to its diagnostic process. The estimated growth rate has a remarkable seasonal cycle with minimum rates occurring in spring and maximum rates evident in autumn. More specifically, the growth rate derived from the meridional advection(surface heat flux) is positive(negative) throughout the year. Vertical diffusion generally makes a negative contribution to the evolution of growth rate and the magnitude of vertical entrainment represents the smallest contributor. Analysis indicates that the zonal advective feedback is regulated by the meridional immigration of the intertropical convergence zone, which approaches its southernmost extent in February and progresses to its northernmost location in September, and dominates the seasonal variation of the SST growth rate.

关键词： SST growth rate intertropical convergence zone zonal advective feedback mixed layer depth ENSO seasonal variation

Role-based Bayesian decision framework for autonomous unmanned systems

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Journal of Systems Engineering and Electronics 2023年第6期34卷 1397-1408页

作者： PANG Weijian MA xinyi LIANG Xueming LIU Xiaogang DONG Erwa Beijing Aeronautical Engineering Research Center Beijing 100076China Academy of Military Sciences Beijing 100091China Air Forces Command College of PLA Beijing 100097China

In the process of performing a task,autonomous unmanned systems face the problem of scene changing,which requires the ability of real-time decision-making under dynamically changing ***,taking the unmanned system coordinative region control operation as an example,this paper combines knowledge representation with probabilistic decisionmaking and proposes a role-based Bayesian decision model for autonomous unmanned systems that integrates scene cognition and individual ***,according to utility value decision theory,the role-based utility value decision model is proposed to realize task coordination according to the preference of the role that individual is ***,multi-entity Bayesian network is introduced for situation assessment,by which scenes and their uncertainty related to the operation are semantically described,so that the unmanned systems can conduct situation awareness in a set of scenes with ***,the effectiveness of the proposed method is verified in a virtual task *** research has important reference value for realizing scene cognition,improving cooperative decision-making ability under dynamic scenes,and achieving swarm level autonomy of unmanned systems.

关键词： autonomous unmanned systems multi-entity Bayesian network(MEBN) situation awareness decision modeling.

Absolute pose estimation of UAV based on large-scale satellite image

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Chinese Journal of Aeronautics 2024年第6期37卷 219-231页

作者： Hanyu WANG Qiang SHEN Zilong DENG xinyi CAO Xiaokang Wang School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Obtaining absolute pose based on pre-loaded satellite images is one of the important means of autonomous navigation for small Unmanned Aerial Vehicles(UAVs)in Global Navigation Satellite System(GNSS)denied *** of the previous works have tended to build Convolutional Neural Networks(CNNs)to extract features and then directly regress the pose,which will fail when solving the challenges caused by the huge viewpoint and size differences between“UAV-satellite”image pairs in real-world ***,this paper proposes a probability distribution/regression integrated deep model with the attention-guided triple fusion mechanism,which estimates discrete distributions in pose space and three-dimensional vectors in translation *** order to overcome the shortage of the relevant dataset,this paper simulates image datasets captured by UAVs with forward-facing cameras during target searching and autonomous *** effectiveness,superiority,and robustness of the proposed method are verified by simulated datasets and flight tests.

关键词： Satellite imagery Unmanned Aerial Vehicle(UAV) Deep neural networks Vision navigation von Mises-Fisher distribution

Insulation and Flame Retardancy Improvement of PBDEs Using 3D-QSAR Model Combined with a Fuzzy Membership Function Method

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Chemical Research in Chinese Universities 2021年第3期37卷 729-738页

作者： ZHANG Shujing XIAO Jiapeng CHEN xinyi LI Yu College of Environmental Science and Engineering North China Electric Power UniversityBeijing102206P.R.China MOE Key Laboratory of Resources and Environmental Systems Optimization North China Electric Power UniversityBeijing102206P.R.China CECEP Talroad Technology Co. Ltd.Beijing100085P.R.China

A three-dimensional quantitative structure-activity relationship(3D-QSAR)model based on the fuzzy membership function method was developed in this study,and then the model was applied to the molecular design of the enhanced comprehensive activities(insulation/flame retardancy)of polybrominated diphenyl ethers(PBDEs)considering their environmental behavior control,to develop environmental-friendly PBDE derivatives with outstanding ***,a fuzzy membership function method was employed to characterize the evaluation values of comprehensive activities of the functional properties of PBDEs based on the 3D-QSAR ***,a comprehensive activity 3D-QSAR model(CoMFA)of the functional properties of PBDEs was established,which demonstrated robustness and good predictive ***,a molecular modification scheme was designed to enhance the comprehensive activity of the functional properties of PBDEs considering the PBDE homologs BDE-138,BDE-183,and BDE-209 as target *** resulting information indicated that the four PBDE derivatives with significantly enhanced functional properties,such as passing screening for toxicity,bioconcentration,migration,and biodegradability assessments with environmentally friendly results,were successfully designed(43.57%-82.14%enhancement).Finally,the mechanism analysis indicated that the enhanced functional properties of the modified PBDE derivatives were significantly related to the substitution positions and substitution groups of PBDEs.

关键词： Polybrominated diphenyl ether Three-dimensional quantitative structure-activity relationship Fuzzy membership function method Insulation/flame retardancy Molecular modification

High performance sandwich structured Si thin film anodes with LiPON coating

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Frontiers of Materials Science 2018年第2期12卷 147-155页

作者： xinyi LUO Jialiang LANG Shasha LV Zhengcao LI State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing 100084 China Key Laboratory of Advanced Materials (MOE) School of Materials Science and Engineering Tsinghua University Beijing 100084 China

The sandwich structured silicon thin film anodes with lithium phosphorus oxynitride （LiPON） coating are synthesized via the radio frequency magnetron sputtering method, whereas the thicknesses of both layers are in the nanometer range, i.e. between 50 and 200 nm. In this sandwich structure, the separator simultaneously functions as a flexible substrate, while the LiPON layer is regarded as a protective layer. This sandwich structure combines the advantages of flexible substrate, which can help silicon release the compressive stress, and the LiPON coating, which can provide a stable artificial solid- electrolyte interphase （SEI） film on the electrode. As a result, the silicon anodes are protected well, and the cells exhibit high reversible capacity, excellent cycling stability and good rate capability. All the results demonstrate that this sandwich structure can be a promising option for high performance Si thin film lithium ion batteries.

关键词： sandwich anode LiPON coating flexible substrate silicon anode

Combination Features,Paleobiogeographic Affinity and Mass Extinction of the Latest Ordovician(Hirnantian) Rugosan Fauna from Northern Guizhou,China

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Acta Geologica Sinica(English Edition) 2007年第1期81卷 23-41页

作者： HE xinyi CHEN Jianqiang XIAO Jingyi China University of Geosciences Beijing 100083 Qinghai Normal University Xining Qinghai 810008

The rugosan fauna from the Guanyinqiao Bed （latest Ordovician, Hirnantian） of northern Guizhou, China is known to belong to the cold or cool-water type corals. The components of the fauna are solitary corals only, and corallite septa are generally strongly dilated, especially the streptelasmatid corals are dominant comprising 98% of the whole fauna. The Guanyinqiao Bed is rich in rugosans of 18 genera, which are streptelasnmtid Streptelasma （=Helicelasma）, Brachyelasma, Amplexobrachyelasma, Salvadorea, Grewingkia, Borelasma, CrassUasma, Leolasma, KenophyUum, UUernelasma, Paramplexoides, Siphonolasma, Pycnactoides, Dalmanophyllum, Bodophyllum, Axiphoria, Lambeophyllum and cystiphyllid Sinkiangolasma. Although this fauna was fairly abundant in a confined area （northern-northeastern Guizhou, southern Sichuan） during the Hirnantian age, the rugosan mass extinction （generic extinction rate 81%） happened at the end of the Hirnantian Stage. It is conduded that the mass extinction is related to the ending of maximum glaciation and ice cap melting in Gondwana in the southern hemisphere in the latest Hirnantian, resulting in rapid global sea-level rise in the earliest Silurian. In the Upper Yangtze Basin, the sea bottom environments were replaced by anoxic and warmer water during that time, so that the cool-water type rugosan became extinct. The present paper attempts to revise some already described rugose coral genera and species （He, 1978, 1985） and to supplement a few new forms from the Guanyinqiao Bed. Fourteen species of 12 genera are re-described and illustrated, of which one species- Grewingkia latifossulata is new. As a whole, the rugosan fauna of the Guanyinqiao Bed may be correlated with those contemporaneous of North Europe, Estonia and North America, indicating a dose biogeographic affinity to North Europe.

关键词： Rugosa cool-water type corals paleobiogeographic affinity mass extinction latest Ordovician northern Guizhou

Numerical Investigation on Characteristics of Supercritical CO_(2)Heat Transfer in Vertical Circular Tubes with Circumferentially Half-Side Heating

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Journal of Thermal Science 2024年第5期33卷 1744-1756页

作者： ZHANG Yan ZHANG xinyi YAN Chenshuai WU Wenhua GAO Erman School of Energy and Power Engineering Northeast Electric Power UniversityJilin 132012China

The design of heat exchangers in the advanced supercritical power conversion system cannot be separated from the study of heat transfer ***-side heating mode is often encountered for solar receiver and supercritical ***,the characteristics of supercritical CO_(2)(sCO_(2))convection heat transfer in vertical tubes with circumferentially half-side heating was numerically investigated through the SST k-ωturbulent model which matches well with the experimental ***,heat transfer between sCO_(2)upflow and downflow was *** to film boiling heat transfer at subcritical pressure,numerical results were processed according to the supercritical pseudo-phase transition hypothesis,with liquid-like phase in the tube core region and vapor-like film in the region near the heated tube *** structure of two layers was demarcated by pseudo-critical temperature T_(pc).Therefore,sCO_(2)heat transfer was assessed according to double thermal resistances caused by vapor-like film near the wall and core liquid-like *** findings suggest that wall temperature for upflow is higher than that for downflow,which is attributed to larger thermal resistance in the fluid domain for upflow than that for *** difference guarantees the excellent heat transfer performance for downflow than *** is also further concluded that the formation of vapor-like film near the wall due to pseudo-phase transition plays a key role in dominating wall temperature and inducing heat transfer deterioration in half-side heating *** present contribution is significant to the design of supercritical heat exchanger under half-side heating mode.

关键词： supercritical CO_(2) pseudo-phase transition half-side heating thermal resistance flow direction

Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile

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原子与分子物理学报 2025年第4期42卷 27-32页

作者： XU Jian-Qiang MA Zhao-Peng CHENG Si LIU Zhi-Cong ZHU Guang-lai Department of Physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241002China

The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this *** following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution *** results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient ***,the excess molar volume initially decreases,reaches a minimum,and then *** rules of radial distribution functions(RDFs)of characteristic atoms are *** increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then *** indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently.

关键词： Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions

Control of Antagonistic McKibben Muscles via a Bio-inspired Approach

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Journal of Bionic Engineering 2022年第6期19卷 1771-1789页

作者： xinyi Chen Wenxin Zhu Wenyu Liang Yilin Lang Qinyuan Ren State Key Laboratory of Industrial Control Technology Zhejiang University310027HangzhouZhejiangChina Institute for Infocomm Research A^(*)STAR138632SingaporeSingapore

McKibben muscles are increasingly used in many robotic applications due to their advantages of lightweight,compliant,and skeletal muscles-like ***,there are still huge challenges in the motion control of McKibben muscles due to the system nonlinearity(e.g.,hysteresis)and model *** investigate the control issues,a soft artificial arm actuated by an antagonistic pair of McKibben muscles,mimicking the biological structure of skeleton-muscle systems,is *** by the biological motor control capability that humans can control and coordinate a group of muscles to achieve complex motions,a cerebellum-like controller based on Spiking Neural Networks(SNNs)is employed for the motion control of the developed artificial *** from the employment of the SNN-based cerebellar model,the proposed control scheme provides online adaptive learning capability,good computational efficiency,fast response,and strong ***,several simulations and experiments are conducted subject to different environmental *** simulation and experimental results verify that the proposed method can achieve good tracking performance,adaptability,and strong robustness.

关键词： McKibben muscle Cerebellum-like controller Spiking Neural Network Soft artificial arm Adaptive control