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Patterns and trajectories of macrophyte change in East China’s shallow lakes over the past one century

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Science China Earth Sciences 2021年第10期64卷 1735-1745页

作者： Feifan huang Ke ZhanG Shixin huang qi LIN State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

Macrophytes play important roles in maintaining ecosystem health and stability of shallow *** understanding of their long-term dynamics has important theoretical and practical significance for both lake ecosystem restoration and eutrophication ***,the knowledge about the historical status and changing patterns of macrophytes in China’s shallow lakes is still controversial and lacks systematic ***,we reviewed and synthesized the published records of submerged macrophytes from 14 typical shallow lakes in the eastern plain covering the past 100 *** results suggest that submerged macrophytes have experienced three clear stages of change:rare period(the 1900s–the 1950s),growth period(the 1950s–the 1980s),and recession period(the 1980s–now).This finding is different from the traditional understanding that submerged macrophytes were abundant in the early 20th century and have been degrading since *** this basis,we proposed the possible evolution pattern(less-more-less)of submerged macrophytes in the eastern plain lake region over the past 100 years,which provides new perspectives about the long-term evolution process of macrophytes in shallow ***,we found that the decline of submerged macrophytes during the regime shift shows a gradual process at the interdecadal scale;this finding contradicts the classical regime shift theory that macrophytes decline sharply during the critical *** study has important theoretical value for the restoration of the eastern plain lakes in China from“turbid lake”to“clear lake”,especially for establishing the historical reference condition and restoration path of macrophytes.

关键词： Macrophyte Submerged macrophyte Eutrophication Shallow lakes Regime shift Climate change

Adaptive sampling for corrugated plate digitization using a laser displacement sensor

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Science China(Technological Sciences) 2024年第5期67卷 1510-1523页

作者： WU ChengXing qi qi CHEN BaiJin YANG JiXiang DING han State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China

The surface quality of a corrugated plate directly determines the heat transfer property of the thermal power mechanical *** detection methods are impractical for real-world production,being slow and *** contrast,the point laser displacement sensor,employing the optical triangle method,emerges as a promising device for assessing parts with variable curvature and highly reflective *** its benefits,high-density sampling by an innate frequency introduces challenges such as data redundancy and a poor signal-to-noise ratio,potentially affecting the efficiency and precision of subsequent data *** address these challenges,adjustable frequency data sampling has been developed for this sensor,allowing adaptive sampling for corrugated plate *** process begins with surface digitization to extract discrete points,which are transformed into intersection curves using the B-spline fitting ***,dominant points are identified,considering multigeometric constraints for curvature and arch ***,the sampling signal is adjusted based on the distribution information of dominant *** results indicate that the proposed method effectively minimizes redundant sampling without compromising the accurate capture of essential geometric features.

关键词： corrugated plate laser displacement sensor adaptive sampling dominant point curvature arch height

Characterizations of gas-liquid interface distribution and slug evolution in a vertical pipe

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Petroleum Science 2023年第5期20卷 3157-3171页

作者： Hai-Yang Yu qiang Xu Ye-qi Cao Bo huang han-Xuan Wang Lie-Jin Guo State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi’an710049ShaanxiChina

Large vertical pipes are key structures connecting subsea wells to offshore ***,existing studies mainly focus on small vertical *** a vertical acrylic pipe with 80 mm inner diameter and 11 m height,a high-speed camera was used to visually research the influences of pipe diameters,liquid properties and inlet effect on air-water co-flow *** flow regime maps of vertical pipes(diameters are in the range of 50e189 mm)were compared and the critical gas velocity of the transition boundary from bubble to slug flow tended to increase with the increase of diameters at D≥80 ***-flux models were established in different flow regimes and liquid properties have a significant effect on drift coefficients of bubble flow and slug flow(void fraction a≤0.4).The influence of inlet turbulent effect on the gas-liquid interface distribution gradually weakened and disappeared from the pipe base to 85D,where the flow was fully *** frequency has a trend of increase first and then decrease with the gas Weber numbers increasing at low liquid superficial velocities(J_(L)≤0.31 m/s).And on the basis of this law,a new slug frequency correlation was *** was found that there was an exponential relationship between the ratio of lengths of Taylor bubble to slug and the void fraction.

关键词： Void fraction Flow regime Drift coefficien Slug frequency Taylor bubble length

Application of Wavelets Transform to Fault Detection in Rotorcraft UAV Sensor Failure

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Journal of Bionic Engineering 2007年第4期4卷 265-270页

作者： Jun-tong qi Jian-da han Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 P. R. China Graduate School Chinese Academy of Sciences Beijing 100049 P. R. China

This paper describes a novel wavelet-based approach to the detection of abrupt fault of Rotorcrafi Unmanned Aerial Vehicle （RUAV） sensor system. By use of wavelet transforms that accurately localize the characteristics of a signal both in the time and frequency domains, the occurring instants of abnormal status of a sensor in the output signal can be identified by the multi-scale representation of the signal. Once the instants are detected, the distribution differences of the signal energy on all decomposed wavelet scales of the signal before and after the instants are used to claim and classify the sensor faults.

关键词： RUAV wavelet transform fault detection sensor failure

Microstructure and Elevated Temperature Tensile Behavior of Directionally Solidified Ni-rich NiAl-Mo(Hf) Alloy

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Journal of Materials Science & Technology 2011年第5期27卷 437-442页

作者： Ping han Yihui qi Jianting Guo Department of Physics Bohai University Jinzhou 121013 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The microstructure, high strain rate superplasticity and tensile creep behavior of directionally solidified （DS） NiAI-Mo（Hf） alloy have been investigated. The alloy exhibits dendritic structure, where dendritic arm is NiAI phase, interdendritic region is Ni3AI phase, and Mo-rich phase distributes in the NiAI and Ni3AI phases. The alloy exhibits high strain rate superplastic deformation behavior, and the maximum elongation is 104.2% at 1373 K and strain rate of 1.04xi0-2 s-I. The balance between strain hardening （by dislocation glide） and strain softening （by dynamic recovery and recrystallization） is responsible for the superplastic deformation. All the creep curves of the DS NiAI-Mo（Hf） alloy have similar shape of a short primary creep and dominant steady creep stages, and the creep strain is great. The possible creep deformation mechanism was also discussed. The creep fracture data follow the Monkman-Grant relationship.

关键词： NiA1 alloy Directional solidification Superplasticity Creep

Novel MOF shell-derived surface modification of Li-rich layered oxide cathode for enhanced lithium storage

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Science Bulletin 2018年第1期63卷 46-53页

作者： Zhitong Xiao Jiashen Meng qi Li Xuanpeng Wang Meng huang Ziang Liu Chunhua han Liqiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing International School of Materials Science and Engineering Wuhan University of Technology Department of Chemistry University of California

Li-rich layered oxide materials have attracted increasing attention because of their high specific capacity(>250 mAh g^(-1)). However, these materials typically suffer from poor cycling stability and low rate performance. Herein, we propose a facile and novel metal-organic-framework(MOF) shell-derived surface modification strategy to construct NiCo nanodots decorated(~5 nm in diameter) carbon-confined Li_(1.2)Mn_(0.54) Ni_(0.13)Co_(0.13)O_2 nanoparticles(LLO@C&NiCo). The MOF shell is firstly formed on the surface of as-prepared Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_2 nanoparticles via low-pressure vapor superassembly and then is in situ converted to the NiCo nanodots decorated carbon shell after subsequent controlled *** obtained LLO@C&NiCo cathode exhibits enhanced cycling and rate capability with a capacity retention of 95% after 100 cycles at 0.4 C and a high capacity of 159 mAh g^(-1) at 5 C, respectively, compared with those of LLO(75% and 105 mAh g^(-1)). The electrochemical impedance spectroscopy and selected area electron diffraction analyses after cycling demonstrate that the thin C&NiCo shell can endow LLO with high electronic conductivity and structural stability, indicating the undesired formation of the spinel phase initiated from the particle surface is efficiently suppressed. Therefore, this presented strategy may open a new avenue on the design of high-performance electrode materials for energy storage.

关键词： Surface modification MOF shell Li-rich layered oxide Lithium-ion battery

Straight-Path Following and Formation Control of USVs Using Distributed Deep Reinforcement Learning and Adaptive Neural Network

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IEEE/CAA Journal of Automatica Sinica 2023年第2期10卷 572-574页

作者： Zhengqing han Yintao Wang qi Sun the School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072China

Dear Editor,This letter presents a distributed deep reinforcement learning(DRL) based approach to deal with the path following and formation control problems for underactuated unmanned surface vehicles(USVs). By constructing two independent actor-critic architectures,the deep deterministic policy gradient(DDPG) method is proposed to determine the desired heading and speed command for each USV.

关键词： Deep policy heading

A TAILORED FINITE POINT METHOD FOR THE HELMHOLTZ EQUATION WITH HIGH WAVE NUMBERS IN HETEROGENEOUS MEDIUM

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Journal of Computational Mathematics 2008年第5期26卷 728-739页

作者： Houde han Zhongyi huang Department of Mathematical Sciences Tsinghua University Beijing 100084 China

In this paper, we propose a tailored-finite-point method for the numerical simulation of the Helmholtz equation with high wave numbers in heterogeneous medium. Our finite point method has been tailored to some particular properties of the problem, which allows us to obtain approximate solutions with the same behaviors as that of the exact solution very naturally. Especially, when the coefficients are piecewise constant, we can get the exact solution with only one point in each subdomain. Our finite-point method has uniformly convergent rate with respect to wave number k in L^2-norm.

关键词： Tailored finite point method Helmholtz equation Inhomogeneous media High frequency wave.

Nano-loaded natural killer cells as carriers of indocyanine green for synergetic cancer immunotherapy and phototherapy

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Journal of Innovative Optical Health Sciences 2019年第3期12卷 24-31页

作者： Shigao huang Chi Ian Fong Mengze Xu Bing-nan han Zhen Yuan qi Zhao Cancer Center Faculty of Health SciencesUniversity of Macao TaipaMacao SARP.R.China† Institute of Translational Medicine Faculty of Health Sciences University of Macao TaipaMacao SARP.R.China School of Life Science Zhejiang Sci-Tech University Zhejiang P.R.China

To improve the efficacy of traditional chemotherapy and radiotherapy and reduce their serious side effects,further efforts need to be exerted to identify better cancer therapeutic options that are effective,affordable,and acceptable to *** this study,a novel theranostic agent was produced to perform synergetic cancer immunotherapy and *** theranostic agent,named natural killer(NK)cells carrying indocyanine green loaded liposomes was synthesized NK cells with ICG nanoparticles to serve as the agent for a newly-established cancer *** is expected that the developed synergistic therapy can pave a new avenue for improved efficacy of cancer theranostics.

关键词： Nanoparticle NK cell photothermal therapy cancer theranostics