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Airborne pollen patterns and their relationship with meteorological factors in the Betula microphylla-dominated wetland of Ebinur Lake,Xinjiang,China

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Science China Earth Sciences 2021年第10期64卷 1746-1760页

作者： Lixin CHEN Yun ZHANG Zhaochen kong State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China College of Earth Sciences Hebei GEO UniversityShijiazhuang 050031China

Airborne pollen is indicative of vegetation and climatic *** study investigates airborne pollen trapping in the Betula microphylla-dominated wetland of Ebinur Lake in Northwestern China from September 2012 to August 2015 using Pearson correlation analysis and the Hybrid Single-particle Lagrangian Integrated Trajectory *** temperatures and moderate precipitation during the flowering period facilitated an increase in birch pollen with more exotic spruce pollen carried from the Tianshan Mountains by airflows,leading to the highest arbor pollen concentrations from September 2012 to August *** pollen concentrations from September 2013 to August 2014 were possibly due to an increase in herbaceous pollen resulting from higher temperatures,lower precipitation and more exotic pollen from the desert of southwest Ebinur Lake and Central Asia in summer and *** September 2014 and August 2015,unfavorable climate conditions in summer and autumn decreased the pollen dispersal of xerophytes such as Artemisia and Chenopodiaceae,with little pollen transported from the Kazakh hilly area in late summer,resulting in the lowest pollen *** parameters and air mass movements both greatly affected the atmospheric pollen *** results provide information concerning the dispersion and distribution of birch pollen,paleoenvironmental reconstruction and wetland conservation.

关键词： Airborne pollen Meteorological factor Pearson correlation Betula pollen Ebinur wetland

Enhanced Natural Convection for Accelerating Melting of Phase Change Material in Cellular Structure through Inserting Fin

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Journal of Thermal Science 2024年第2期33卷 548-563页

作者： kong Dekui ZHANG Yongcun LIU Shutian State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of TechnologyDalian116024China

The design of thermal conductivity enhancers(TCE) is quite critical to overcoming the disadvantage of the poor thermal conductivity of phase change materials(PCM).The main contribution of this study is firstly to discuss how to actively enhance natural convection of the melted PCM in cellular structure by the fin formed in the structure under the condition of the same metal mass,apart from simultaneously improving heat conduction,which can boost the heat transfer ***,a tailored hybrid fin-lattice structure(HFS) as TCE is designed and fabricated by additive manufacturing(AM).A two-equation numerical method is applied to study the heat transfer of the PCM,and its feasibility is validated with the experimental *** numerical results indicate that enhanced natural convection and improved heat conduction can be obtained simultaneously when a well-designed fin is embedded into a lattice *** enhanced natural convection results in the improved melting rate and the decreased wall temperature;e.g.,the complete melting time and the wall temperature are reduced by 11.6% and 19.7%,respectively,because of the fin for metal ***,the parameters of HFS including the porosity,pore density,and fin dimension have a great impact on the heat *** enhancement effect of the fin for HFS on the melting rate of the PCM increases as the thermal conductivity of the base material *** example,when the fin is introduced into the lattice structure,the complete melting time is reduced by 24.1% for metal *** summary,this study enables us to obtain a good understanding of the mechanism of the heat transfer and provides necessary experimental data for the structural design of HFS fabricated by AM.

关键词： natural convection heat transfer enhancement phase change material additive manufacturing hybrid fin-lattice structure

Optimization and Experimental Study of Bionic Compliant End-effector for Robotic Cherry Tomato Harvesting

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Journal of Bionic Engineering 2022年第5期19卷 1314-1333页

作者： Huaibei Xie Deyi kong Qiong Wang Institute of Intelligent Machines Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Science Island Branch of Graduate School University of Science and Technology of ChinaHefei 230026China School of Mechanical Engineering Anhui University of Science and TechnologyHuainan 232001China Innovation Academy for Seed Design Chinese Academy of SciencesSanya 572024China

High harvesting success rate is part of the key technologies for robotic cherry tomato harvesting,which is closely related to the structural design of the *** obtain a high success rate of fruit harvesting,this paper presents a compliant end-effector with bio-inspired tarsus compliant gripper inspired by the structure and mechanics of the tarsal chain in the Serica orientalis *** Surface Methodology(RSM)based on Box Behnken Design(BBD)technique has been used to optimize the key structural parameters of the bionic compliant end-effector for achieving the expected results in pulling pattern for robotic cherry tomato *** were designed by maintaining three levels of four process parameters—Length of the Offset Segment Tarsomere(OSTL),Angle of the Inclined Segment Tarsomere(ISTA),Thickness of the Extended Segment Tarsomere(ESTT)and Length of the Extended Segment Tarsomere(ESTL).According to the optimization analysis results,the best parameter combination is OSTL 23 mm,ISTA 14°,ESTT 5.0 mm,ESTL 23 ***,the harvesting performance of the optimized bionic compliant end-effector was verified by *** results indicated the harvesting success rate of fruits with different equatorial diameters was not less than 76%.

关键词： Compliant end-efector Bio-inspired tarsus gripper Response surface Configuration optimization Cherry tomato Robotic harvesting

Test on Stochastic Block Model:Local Smoothing and Extreme Value Theory

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Journal of Systems Science & Complexity 2022年第4期35卷 1535-1556页

作者： WU Fan kong Xinbing XU Chao School of Mathematics Southeast UniversityNanjing211819China School of Statistics and Mathematics Nanjing Audit UniversityNanjing211815China School of Information Engineering Nanjing Audit UniversityNanjing211815China

In this paper,to obtain a consistent estimator of the number of communities,the authors present a new sequential testing procedure,based on the locally smoothed adjacency matrix and the extreme value *** the null hypothesis,the test statistic converges to the type I extreme value distribution,and otherwise,it explodes fast and the divergence rate could even reach n in the strong signal case where n is the size of the network,guaranteeing high detection *** method is simple to use and serves as an alternative approach to the novel one in Lei(2016)using random matrix *** detect the change of the community structure,the authors also propose a two-sample test for the stochastic block model with two observed adjacency *** studies justify the *** authors apply the proposed method to the political blog data set and find reasonable group structures.

关键词： Extreme value distribution network data stochastic block model

Polymer-to-Monomers Chemically Recyclable Poly(imide-imine)Plastics with Extreme-Condition Resistance and Flame Retardancy

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Chinese Journal of Polymer Science 2024年第10期42卷 1525-1535,I0012页

作者： Zhen-Yu Wang Xiao-kong Liu State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun130012China

Polyimides are a family of high-tech plastics that have irreplaceable applications in the fields of aerospace,defense,and opto-electronics,but polyimides are difficult to be reprocessed and recycled at the end of their service life,resulting in a significant waste of ***,it is of great significance to develop recyclable polyimides with comparable properties to the commercial ***,we report a novel polymer-to-monomers chemically recyclable poly(imide-imine)(PtM-CR-PII)plastic,synthesized by cross-linking the amine-terminated aromatic bisimide monomer and the hexa-vanillin terminated cyclophosphazene monomer via dynamic imine *** PtM-CR-PII plastic exhibits comparable mechanical and thermal properties as well as chemical stability to the commercial *** PtM-CR-PII plastic possesses a high Young’s modulus of≈3.2 GPa and a tensile strength as high as≈108 MPa,which also exhibits high thermal stability with a glass transition temperature of≈220℃.Moreover,the PtM-CR-PII plastic exhibits outstanding waterproofness,acid/alkali-resistance,and solvent-resistance,its appearance and mechanical properties can be well maintained after long-term soaking in water,highly concentrated acid and base,and various organic ***,the cyclophosphazene moieties endow the PtM-CR-PII plastic with excellent flame *** PtM-CR-PII plastic exhibits the highest UL-94 flame-retarding rating of V-0 and a limiting oxygen index(LOI)value of 45.5%.Importantly,the PtM-CR-PII plastic can be depolymerized in an organic solvents-acid mixture medium at room temperature,allowing easy separation and recovery of both monomers in high *** recovered pure monomers can be used to regenerate new PtM-CR-PII plastics,enabling sustainable polymer-monomers-polymer circulation.

关键词： Chemical recyclability Polyimides Polyimines Dynamic imine bonds Mechanical properties Chemical stability

Recent progresses of NMOS and CMOS logic functions based on two-dimensional semiconductors

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Nano Research 2021年第6期14卷 1768-1783页

作者： Lingan kong Yang Chen Yuan Liu Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education School of Physics and ElectronicsHunan UniversityChangsha410082China

Metal-oxide-semiconductor field effect transistors(MOSFET)based on two-dimensional(2D)semiconductors have attracted extensive attention owing to their excellent transport properties,atomically thin geometry,and tunable *** improving the transistor performance of individual device,lots of efforts have been devoted to achieving 2D logic functions or integrated circuit towards practical *** this review,we discussed the recent progresses of 2D-based logic *** will first start with the different methods for realization of n-type metal-oxide-semiconductor(NMOS)-only(or p-type metal-oxide-semiconductor(PMOS)-only)logic ***,various device polarity control and complementary-metal-oxide-semiconductor(CMOS)approaches are summarized,including utilizing different 2D semiconductors with intrinsic complementary doping,charge transfer doping,contact engineering,and electrostatics *** will discuss the merits and drawbacks of each approach,and lastly conclude with a short perspective on the challenges and future developments of 2D logic circuit.

关键词： field effect transistors two-dimensional semiconductors logic circuit complementary-metal-oxide-semiconductor(CMOS) polarity control

Cross-Linguistic Influence in Hong kong ESL Learners' Acquisition of Conjunctions

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Fudan Journal of the Humanities and Social Sciences 2023年第4期16卷 515-539页

作者： Ming Sum kong Mary Carr Sin Wang Chong International Education Institute University of St.AndrewsKinessburn Kennedy GardensSt Andrews KY169DJUK Student Services University of DundeeDundee DD14HNUK

Language transfer is one of the most significant aspects of cross-linguistic *** can be divided into two types:positive and negative,the beneficial and det-rimental use of one language's acquired characteristics in *** study aims to investigate the L1(Chinese)influence on Hong kong ESL learners'acquisition of conjunctions and whether the use of L1 has an impact on this *** online questionnaire combining questions about students'English learning experience and a grammatical judgement task was sent to a government-funded secondary school in Hong kong and completed by 79 *** of both positive and negative transfer from Chinese to English was found by testing six conjunctions or conjunc-tion pairs:although...but,because...so,not only...but also,either...or,neither...nor,.and *** results suggest that Chinese is likely to have an impact on students'acquisition of conjunctions,and the use of Chinese in English classes can worsen negative transfer and boost positive *** degree of transfer might increase when more Chinese is used in *** alleviate the impact of Chinese transfer and to provide more effective L2 teaching,monitoring the use of L1 and regular evalua-tion might be *** can also adjust the amount of Chinese used according to the students'English proficiency level.

关键词： Cross-linguistic influence Language transfer Conjunctions Hong kong ESL learners

Augmented Industrial Data-Driven Modeling Under the Curse of Dimensionality

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IEEE/CAA Journal of Automatica Sinica 2023年第6期10卷 1445-1461页

作者： Xiaoyu Jiang Xiangyin kong Zhiqiang Ge the State Key Laboratory of Industrial Control Technology College of Control Science and EngineeringZhejiang UniversityHangzhou 310027China the Peng Cheng Laboratory Shenzhen 518000China

The curse of dimensionality refers to the problem o increased sparsity and computational complexity when dealing with high-dimensional *** recent years,the types and vari ables of industrial data have increased significantly,making data driven models more challenging to *** address this prob lem,data augmentation technology has been introduced as an effective tool to solve the sparsity problem of high-dimensiona industrial *** paper systematically explores and discusses the necessity,feasibility,and effectiveness of augmented indus trial data-driven modeling in the context of the curse of dimen sionality and virtual big ***,the process of data augmen tation modeling is analyzed,and the concept of data boosting augmentation is *** data boosting augmentation involves designing the reliability weight and actual-virtual weigh functions,and developing a double weighted partial least squares model to optimize the three stages of data generation,data fusion and *** approach significantly improves the inter pretability,effectiveness,and practicality of data augmentation in the industrial ***,the proposed method is verified using practical examples of fault diagnosis systems and virtua measurement systems in the *** results demonstrate the effectiveness of the proposed approach in improving the accu racy and robustness of data-driven models,making them more suitable for real-world industrial applications.

关键词： Index Terms—Curse of dimensionality data augmentation data-driven modeling industrial processes machine learning

Adaptive algorithm for estimating excavation-Induced displacements using field performance data

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Underground Space 2020年第2期5卷 115-124页

作者： Haijian Fan Gangqiang kong Transportation Engineer Texas Department of TransportationUSA College of Civil and Transportation Engineering Hohai UniversityNanjingJiangsu ProvinceChina

Empirical models provide a practical way to estimate the displacements induced by ***,there are uncertainties associated with the predictions of empirical models owing to:(a)the imperfect knowledge of the model and(b)the uncertainties of the input *** uncertainties of these models can be characterized by a bias factor which is defined as the ratio of the actual displacement to the predicted *** bias factors associated with the C&O method and the KJHH model are evaluated using the Bayesian method and a database of 71 excavations in *** improve the predictions of the maximum displacement,an adaptive algorithm is proposed using field performance *** performance of the proposed algorithm is demonstrated by an example in which excavation-induced displacements are generated by finite element method in normally consolidated *** example shows that the developed algorithm can significantly improve the predictions by incorporating the field performance data.

关键词： Excavation Displacement prediction Bayesian updating Model bias