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A novel intelligent adaptive control of laser-based ground thermal test

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Chinese Journal of Aeronautics 2016年第4期29卷 1018-1026页

作者： Gan Zhengtao Yu Gang Li Shaoxia He Xiuli Chen Ru Zheng Caiyun ning weijian Key Laboratory of Mechanics in Advanced Manufacturing Institute of Mechanics Chinese Academy of Sciences

Laser heating technology is a type of potential and attractive space heat flux simulation technology, which is characterized by high heating rate, controlled spatial intensity distribution and rapid response. However, the controlled plant is nonlinear, time-varying and uncertainty when implementing the laser-based heat flux simulation. In this paper, a novel intelligent adaptive controller based on proportion-integration-differentiation (PID) type fuzzy logic is proposed to improve the performance of laser-based ground thermal test. The temperature range of thermal cycles is more than 200 K in many instances. In order to improve the adaptability of controller, output scaling factors are real time adjusted while the thermal test is underway. The initial values of scaling factors are optimized using a stochastic hybrid particle swarm optimization (H-PSO) algorithm. A validating system has been established in the laboratory. The performance of the proposed controller is evaluated through extensive experiments under different operating conditions (reference and load disturbance). The results show that the proposed adaptive controller performs remarkably better compared to the conventional PID (PID) controller and the conventional PID type fuzzy (F-PID) controller considering performance indicators of overshoot, settling time and steady state error for laser-based ground thermal test. It is a reliable tool for effective temperature control of laser-based ground thermal test. (C) 2016 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license.

关键词： Adaptive control Fuzzy logic Ground thermal test Laser heating Thermal control

Numerical simulation of powder transport behavior in laser cladding with coaxial powder feeding

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Science China(Physics,Mechanics & Astronomy) 2015年第10期58卷 28-37页

作者： LIU Hao HE XiuLi YU Gang WANG Zhong Bin LI ShaoXia ZHENG CaiYun ning weijian School of Mechanical and Electrical Engineering China University of Mining and Technology Jiangsu Key Laboratory of Mine Mechanical and Electrical Equipment China University of Mining and Technology Key Laboratory of Mechanics in Advanced Manufacturing Institute of Mechanics Chinese Academy of Sciences

Laser cladding with coaxial powder feeding is one of the new ponent to improve performance of its surface. In the process, processes applied to produce well bonding coating on the com- the clad material is transported by the carrying gas through the coaxial nozzle, generating gas-powder flow. The powder feeding process in the coaxial laser cladding has important influence on the clad qualities. A 3D numerical model was developed to study the powder stream structure of a coaxial feeding nozzle. The predicted powder stream structure was well agreed with the experimental one. The validated model was used to explore the collision behavior of particles in the coaxial nozzle, as well as powder concentration distribution. It was found that the par- ticle diameter and restitution coefficient greatly affect the velocity vector at outlet of nozzle due to the collisions, as well as the powder stream convergence characteristics below the nozzle. The results indicated a practical approach to optimize the powder stream for the coaxial laser cladding.

关键词： laser cladding solid-gas flow numerical simulation collision behavior

激光熔覆Ta-W合金组织及高温气动烧蚀性能

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稀有金属材料与工程 2012年第7期41卷 1211-1215页

作者：武扬虞钢何秀丽宁伟健中国科学院力学研究所北京100190

以纯W粉末为熔覆材料,纯Ta为基底,采用同轴送粉激光熔覆技术在Ta板侧面制备了Ta-W合金涂层。利用扫描电镜(SEM)、能谱(EDS)及显微硬度计对熔覆层的微观组织和显微硬度进行了分析,在直联式自由射流风洞试验台上对涂层的抗高温高速气流烧... 详细信息

以纯W粉末为熔覆材料,纯Ta为基底,采用同轴送粉激光熔覆技术在Ta板侧面制备了Ta-W合金涂层。利用扫描电镜(SEM)、能谱(EDS)及显微硬度计对熔覆层的微观组织和显微硬度进行了分析,在直联式自由射流风洞试验台上对涂层的抗高温高速气流烧蚀性能进行了测试。结果表明,熔覆层与基底冶金结合,涂层内部为致密的树枝状Ta-W合金固溶体,大致均匀地分布于Ta中。Ta-W合金涂层平均HV硬度8GPa,为基材的5倍,同时抗烧蚀性能得到了显著提高。

关键词：激光熔覆同轴送粉 Ta-W合金显微组织烧蚀性能

Unmasking Social Robots’Camouflage:A GNN-Random Forest Framework for Enhanced Detection

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Computers, Materials & Continua 2025年第1期82卷 467-483页

作者： weijian Fan Chunhua Wang Xiao Han Chichen Lin School of Data Science and Intelligent Media Communication University of ChinaBeijing100024China School of Computer and Cyber Sciences Communication University of ChinaBeijing100024China Institute of Communication Studies Communication University of ChinaBeijing100024China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

The proliferation of robot accounts on social media platforms has posed a significant negative impact,necessitating robust measures to counter network anomalies and safeguard content *** robot detection has emerged as a pivotal yet intricate task,aimed at mitigating the dissemination of misleading *** graphbased approaches have attained remarkable performance in this realm,they grapple with a fundamental limitation:the homogeneity assumption in graph convolution allows social robots to stealthily evade detection by mingling with genuine human *** unravel this challenge and thwart the camouflage tactics,this work proposed an innovative social robot detection framework based on enhanced HOmogeneity and Random Forest(HORFBot).At the core of HORFBot lies a homogeneous graph enhancement strategy,intricately woven with edge-removal techniques,tometiculously dissect the graph intomultiple revealing ***,leveraging the power of contrastive learning,the proposed methodology meticulously trains multiple graph convolutional networks,each honed to discern nuances within these tailored *** culminating stage involves the fusion of these feature-rich base classifiers,harmoniously aggregating their insights to produce a comprehensive detection *** experiments on three social robot detection datasets have shown that this method effectively improves the accuracy of social robot detection and outperforms comparative methods.

关键词： Social robot detection graph neural networks random forest homophily heterophily

A breakthrough of printable mesoscopic perovskite solar cells

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Science China Materials 2025年第1期68卷 307-308页

作者： Zhiyi Yao Zhijun ning School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China

High-performance solar cells based on low-cost wet coating methods are the much-anticipated technology for the next generation of photovoltaics. Perovskite solar cells (PSCs) provide a fascinating choice because their... 详细信息

关键词： perovskite breakthrough absorber

Profiles,exposure assessment and expanded screening of PAHs and their derivatives in one petroleum refinery facility of China

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Journal of Environmental Sciences 2025年第1期147卷 550-560页

作者： ning Wang Fengjiao Jiang Lin Xu Yaqi Cai School of Municipal and Environmental Engineering Shandong Jianzhu UniversityJinan 250101China Resource and Environmental Innovation Institute Shandong Jianzhu UniversityJinan 250101China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou 330106China Hubei Key Laboratory of Environmental and Health Effects of Persistence Toxic Substances Institute of Environment and HealthJianghan UniversityWuhan 430056China

This study investigated environmental distribution and human exposure of polycyclic aromatic hydrocarbons(PAHs)and their derivatives in one Chinese petroleum refinery *** was found that,following with high concentrations of 16 EPA PAHs(∑Parent-PAHs)in smelting subarea of studied petroleum refinery facility,total derivatives of PAHs[named as XPAHs,including nitro PAHs(NPAHs),chlorinated PAHs(Cl-PAHs),and brominated PAHs(Br-PAHs)]in gas(mean=1.57×10^(4)ng/m^(3)),total suspended particulate(TSP)(mean=4.33×10^(3) ng/m^(3))and soil(mean=4.37×10^(3) ng/g)in this subarea had 1.76-6.19 times higher levels than those from other subareas of this facility,surrounding residential areas and reference areas,indicating that petroleum refining processes would lead apparent derivation of ***,compared with those in residential and reference areas,gas samples in the petrochemical areas had higher∑NPAH/∑PAHs(mean=2.18),but lower∑Cl-PAH/∑PAHs(mean=1.43×10^(-1))and∑Br-PAH/∑PAHs ratios(mean=7.49×10^(-2)),indicating the richer nitrification of PAHs than chlorination during petrochemical *** occupational exposure to PAHs and XPAHs in this petroleum refinery facility were 24-343 times higher than non-occupational exposure,and the ILCR(1.04×10^(-4))for petrochemical workers was considered to be potential high ***,one expanded high-resolution screening through GC Orbitrap/MS was performed for soils from petrochemical area,and another 35 PAHs were found,including alkyl-PAHs,phenyl-PAHs and other species,indicat-ing that profiles and risks of PAHs analogs in petrochemical areas deserve further expanded investigation.

关键词： Polycyclic aromatic hydrocarbons(PAHs) Derivatives Petroleum refinery Human exposure Non-targeted screening

Differential-geometry-based multi-dimensional joint position-velocity estimation using Crab pulsar profile distortion

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Chinese Journal of Aeronautics 2025年第1期38卷 551-567页

作者： Jin LIU Huanzi ZHANG Xiaolin ning Xin MA School of Electronic Information Wuhan University of Science and TechnologyWuhan 430081China School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China Hefei National Laboratory Hefei 230088China

The traditional orbit determination method based on pulsar profile distortion can determine the six elements of the ***,the estimation accuracies of these methods are limited and the computational load of a six-dimensional search is *** solve this problem,the differential-geometry-based Multi-dimensional Joint Position-Velocity Estimation(MJPVE)using Crab pulsar profile distortion is proposed in this ***,through theoretical analysis,it is found that the pulsar profile distortion caused by the initial state error in some joint positionvelocity directions is very *** other words,the accuracies of estimation in these directions are very ***,the search dimension can be reduced,which in turn greatly reduces the computational ***,we construct the chi-squared function of the pulsar profile with respect to the estimation error in joint position-velocity direction and use differential geometry to find the joint position-velocity directions corresponding to different degrees of ***,we utilize the grid search based on directory folding in these joint position-velocity directions corresponding to large degrees of distortion to obtain the joint position-velocity *** experimental results show that compared with the grouping bi-chi-squared inversion method,MJPVE has high precision and extensive navigation information.

关键词： Joint Position-Velocity Estimation Pulsars Profile Distortion Orbit Determination Differential Geometry

A new exceptionally preserved corystosperm wood from the Jurassic of East Asia

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Science China Earth Sciences 2025年第3期68卷 803-810页

作者： Zikun JIANG ning TIAN Yongdong WANG Fangyu LI Junling PEI Dieter UHL Ya LI Hao WU Zhenguo ning Ruiying HAO Chinese Academy of Geological Sciences College of Palaeontology Shenyang Normal University Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences College of Resources and Environmental Engineering Guizhou University East China University of Technology Senckenberg Research Institute and Natural History Museum Frankfurt Zhejiang Museum of Natural History Department of Natural Resources of Shandong Province

Corystosperms, an extinct group of “seed ferns” that lived from the late Permian to the Cretaceous or Eocene, are significant for seed plant phylogeny for their unique roles in partially resolving the long-standing question of angiosperm origins.A new fossil wood taxon, Fengweioxylon sinense gen. et sp. nov. is reported here based on exceptionally preserved wood material from the Jurassic in western Liaoning, China, whose peculiar wood structure enables it to be recognized as the first unequivocal fossil wood record of a corystosperm plant in Laurasia. The anatomical structures of this corystosperm wood show gymnospermous characters. The discovery of the new specimen will provide more anatomical evidence for understanding the systematic and affinity of this seed plants.

关键词： Corystosperms Fossil wood Laurasia Jurassic

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Enhancing microbial superoxide generation and conversion to hydroxyl radicals for enhanced bioremediation using iron-binding ligands

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Journal of Environmental Sciences 2025年第1期147卷 597-606页

作者： Yuhan Wang Xue ning Jinsong Liang Aijie Wang Jiuhui Qu School of Civil and Environmental Engineering Harbin Institute of TechnologyShenzhen 518055China SFI MaREI Centre for Energy Climate and MarineEnvironmental Research InstituteUniversity College CorkCorkIreland Center for Water and Ecology Tsinghua UniversityBeijing 100084China

Harnessing bacteria for superoxide production in bioremediation holds immense promise,yet its practical application is hindered by slow production rates and the relatively weak redox potential of *** study delves into a cost-effective approach to amplify superoxide production using an Arthrobacter strain,a prevalent soil bacterial *** research reveals that introducing a carbon source along with specific iron-binding ligands,including deferoxamine(DFO),diethylenetriamine pentaacetate(DTPA),citrate,and oxalate,robustly augments microbial superoxide ***,our findings suggest that these iron-binding ligands play a pivotal role in converting superoxide into hydroxyl radicals by modulating the electron transfer rate between Fe(Ⅲ)/Fe(Ⅱ)and ***,among the tested ligands,only DTPA emerges as a potent promoter of this conversion process when complexed with Fe(Ⅲ).We identify an optimal Fe(Ⅲ)to DTPA ratio of approximately 1:1 for enhancing hydroxyl radical production within the Arthrobacter *** research underscores the efficacy of simultaneously introducing carbon sources and DTPA in facilitating superoxide production and its subsequent conversion to hydroxyl radicals,significantly elevating bioremediation ***,our study reveals that DTPA augments superoxide production in cultures of diverse soils,with various soil microorganisms beyond Arthrobacter identified as contributors to superoxide *** emphasizes the universal applicability of DTPA across multiple bacterial *** conclusion,our study introduces a promising methodology for enhancing microbial superoxide production and its conversion into hydroxyl *** findings hold substantial implications for the deployment of microbial reactive oxygen species in bioremediation,offering innovative solutions for addressing environmental contamination challenges.

关键词： Superoxide Hydroxyl radical Iron-binding ligand Bioremediation DTPA