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Experimental and numerical studies on buckling and post-buckling behavior of T-stiffened variable stiffness panels

Chinese Journal of Aeronautics 2024年第10期37卷 459-470页

作者： Yan HUANG Yahui ZHANG Bin KONG Jiefei GU Zhe WANG Puhui CHEN State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China AVIC Aviation Power Control System Research Institute Wuxi 214063China Chengdu Aircraft Design and Research Institute Aviation Industry Corporation of ChinaChengdu 610091China School of Mechanical Engineering Jiangnan UniversityWuxi 214122China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China China National Key Laboratory of Strength and Structural Integrity Aircraft Strength Research Institute of ChinaXi’an 710065China

Currently,experimental research on variable stiffness design mainly focuses on *** ensure adaptability in practical application,it is imperative to conduct a systematic study on stiffened variable stiffness structures,including design,manufacture,experiment,and *** on the minimum curvature radius and process schemes,two types of T-stiffened panels were designed and *** compression tests have been carried out and the results indicate that the buckling load of variable stiffness specimens is increased by 26.0%,while the failure load is decreased by 19.6%.The influence mechanism of variable stiffness design on the buckling and failure behavior of T-stiffened panels was explicated by numerical *** primary reason for the reduced strength is the significantly increased load bearing ratio of *** experimental investigations of stiffened variable stiffness structures are very rare,this study can be considered a reference for future work.

关键词： Variable stiffness composite Buckling Post-buckling Finite element method Stiffened panels

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A nonsingular terminal sliding algorithm for swing and stance control of a prosthetic leg robot

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Applied Mathematical Modelling 2023年 113卷 13-29页

作者： Jafari, Maryam Mobayen, Saleh Bayat, Farhad Roth, Hubert Department of Electrical Engineering University of Zanjan Zanjan38791-45371 Iran Future Technology Research Center National Yunlin University of Science and Technology Yunlin Douliou64002 Taiwan Hubert Roth is with the Institute of Automatic Control Engineering University of Siegen Siegen Germany

The design of swing and stance control for path following of a prosthetic leg robot subject to uncertain dynamics and exterior disturbances is a serious issue, which affects the development of wearable robots. In wearable robots, parametric uncertainties and external disturbances are unavoidable problems. This problem is associated with practical engineering of wearable robots due to the actual swing and stance situations, where the combination of contact and tracking control objectives is highly complex. This paper proposes two novel finite-time controllers for a prosthetic leg robot with three degree-of-freedom. A prosthetic leg robot should emulate hip vertical displacement, thigh and knee angles according to human gaits in the presence of ground friction force and external disturbances. For the swing phase, a nonsingular fast terminal sliding mode control method is designed to track the reference trajectories fast and in the finite time without any non-singularity problem and chattering phenomenon. Moreover, the other designed controller can deal with input saturation by using a hyperbolic tangent function and an auxiliary system. For the stance phase, an impulse momentum sliding mode control scheme is introduced which allows the prosthetic leg robot to emulate the mechanics of human walking. Using the proposed controller, the robot imitates the patient momentum exchange and weight transfer in the stance phase. The proposed techniques cause the transition between contact and off-contact phases and contact phase itself. Finally, the simulation results verify the efficiency of the provided technique. In our future work, we will focus on employing this technique to a practical prosthesis legged robot. © 2022 Elsevier Inc.

关键词： Prosthetics

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research on pedestrian flow detection algorithm based on Ghostnetv2 lightweight network 3

Research on pedestrian flow detection algorithm based on Gho...

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3rd International Conference on Advanced Algorithms and Signal Image Processing, AASIP 2023

作者： Lyu, Jin Yang, Jing Shao, Ruping Zhou, Wang College of Electrical Engineering and Control Science Nanjing Tech University Nanjing211816 China Engineering Research Center of BIM Nanjing Tech University Nanjing211816 China

ISBN: (纸本)9781510668522

To solve the problems of a large number of parameters, low detection accuracy, slow detection speed of human flow target detection model, this paper proposes a YOLOv5 human flow target detection model based on GhostNetv2. The convolution in the first layer of CBS is retained to replace the remaining convolutions with Ghost Conv, and the C3Ghostv2 module is constructed to replace the original CSP structure, reducing the number of parameters, reducing the calculation cost and improving the calculation speed. Finally, the Deep-Sort algorithm tracks and realizes real-Time statistics of people flow. The experimental results indicate that the accuracy of the improved YOLOv5 model is 2.4 percentage points higher than that of the original algorithm, the parameter quantity is compressed by 28 %, and the detection speed has also increased. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.

关键词： Convolution

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Evaluating A* and RRT for High-DoF Path Planning 1

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8th International Scientific Conference on Intelligent Information Technologies for Industry, IITI 2024

作者： Onegin, Aleksandr Kerimov, Nuraddin Yakovlev, Konstantin Moscow Institute of Physics and Technology Moscow Russia Federal Research Center for Computer Science and Control of Russian Academy of Sciences Moscow Russia

ISBN: (数字)9783031776885

ISBN: (纸本)9783031776878

Path planning is crucial for various robots, including manipulators, that autonomously perform non-repetitive tasks in obstacle-rich environments. In this paper we focus on path planning for an n-DoF (degrees of freedom) manipulator, i.e. the one that consists of n links and n joints. We evaluate and compare head-to-head two approaches that are the most commonly used to solve this problem: search-based planning in the discretized configuration space and sampling-based planning in the continuous space. We evaluate the planners in challenging obstacle-rich scenes while varying the dimensionality of the configuration space (the number of joints/links). The memory consumption, quality of the resultant paths, runtime are tracked. Our evaluation reveals that, despite the common belief, search-based methods can outperform the sampling-based ones for 3-DoF and even 4-DoF manipulators, however for higher dimensional spaces (5-DoF and more) sampling methods are, indeed, more preferable. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024.

关键词： Degrees of freedom (mechanics)

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Comprehensive newborn screening for severe combined immunodefciency,X‑linked agammaglobulinemia,and spinal muscular atrophy:the Chinese experience

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World Journal of Pediatrics 2024年第12期20卷 1270-1282页

作者： Chi Chen Chao Zhang Ding-Wen Wu Bing-Yi Wang Rui Xiao Xiao-Lei Huang Xin Yang Zhi-Gang Gao Ru-Lai Yang Department of Genetics and Metabolism Children’s HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhouChina National Engineering Laboratory for Key Technology of Birth Defect Control and Prevention Screening and Diagnostic R and D CenterHangzhouChina

Background Newborn screening(NBS)for severe combined immunodefciency(SCID),X-linked agammaglobulinemia(XLA),and spinal muscular atrophy(SMA)enables early diagnosis and intervention,signifcantly improving patient *** in real-time polymerase chain reaction(PCR)technology have been instrumental in facilitating their inclusion in NBS *** We employed multiplex real-time PCR to simultaneously detect T-cell receptor excision circles(TRECs),kappadeleting recombination excision circles(KRECs),and the absence of the survival motor neuron(SMN)1 gene in dried blood spots from 103,240 newborns in Zhejiang Province,China,between July 2021 and December *** Of all the samples,122 were requested further *** fow cytometry evaluation and/or genetic diagnostics,we identifed one patient with SCID,two patients with XLA,nine patients with SMA[one of whom also had Wiskott–Aldrich Syndrome(WAS)],and eight patients with other medical *** positive predictive values(PPVs)of NBS for SCID,XLA,and SMA were 2.44%,2.78%,and 100%,*** estimated prevalence rates in the Chinese population were 1 in 103,240 for SCID,1 in 51,620 for XLA,and 1 in 11,471 for *** This study represents the frst large-scale screening in China's Mainland using a TREC/KREC/SMN1 multiplex assay,providing valuable epidemiological *** fndings suggest that this multiplex assay is an efective screening method for SCID,XLA,and SMA,potentially supporting the universal implementation of NBS programs across China.

关键词： Genetic diagnosis Newborn screening Severe combined immunodefciency Spinal muscular atrophy X-linked agammaglobulinemia

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Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang Zhang Danyang Wu Linke Cai Youluan Lu Fanpeng Cheng Lijuan Shi Qun Yi Yao Liu Yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationHubei Key Laboratory of Novel Reactor and Green Chemical TechnologySchool of Chemical Engineering&PharmacyWuhan Institute of TechnologyWuhan 430205HubeiChina Key Laboratory of Pesticide&Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of EducationCollege of ChemistryCentral China Normal UniversityWuhan 430079HubeiChina College of Materials Science and Engineering Fuzhou UniversityFuzhou 350108FujianChina

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction(OER).Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER ***,most of them undergo incomplete reconstruction with limited thickness of reconstruction layer,leading to low component utilization and arduous exploration of real catalytic ***,we identify the dynamic behaviors in complete reconstruction of Co-based complexes during *** hollow phytic acid(PA)cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability,in favor of the fast and complete reconstruction.A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co(Fe)(OH)xand subsequent potential-driven oxidation to Co(Fe)*** obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm^(-2)and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER *** work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Complete reconstruction Co-based complex Precatalysts Oxygen evolution reaction

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Organic frameworks confined Cu single atoms and nanoclusters for tandem electrocatalytic CO_(2) reduction to methane

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SmartMat 2022年第1期3卷 183-193页

作者： Qinglan Zhao Yian Wang Meng Li Shangqian Zhu Tiehuai Li Jixiang Yang Ting Lin Ernest PDelmo Yinuo Wang Juhee Jang Meng Gu Minhua Shao Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyHong KongChina Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials College of Life Science and TechnologyJinan UniversityGuangzhouChina Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhenChina Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution Energy InstituteThe Hong Kong University of Science and TechnologyHong KongChina

The electrochemical reduction reaction of carbon dioxide(CO_(2)RR)is considered to be an effective way to realize carbon *** a type of intensively studied materials,covalent organic frameworks(COFs)with a tunable pore structure and various functional groups are promising catalysts for CO_(2)***,COF synthesized by 2,6‐diaminoanthraquinone and 2,4,6‐triformylphloroglucinol is employed to assist the synthesis of electrocatalysts from Cu single atoms(SAs)to nanoclusters by controlling the electrodeposition.A tandem catalyst for CO_(2)‐to‐CH4 conversion is thus achieved by the Cu nanoclusters dispersed among the isolated Cu SAs in the COF *** is proposed that CO_(2) is first reduced to CO over the atomically isolated Cu SAs,followed by diffusion onto the neighboring Cu nanoclusters for further reduction into *** addition,mechanistic analysis suggests that the coordinated K^(+)ions on the COF network promote the activation of CO_(2) and the adsorption of reaction intermediates,thus realizing the suppressed hydrogen evolution reaction and selective production of *** study presents a new insight of COFs for the confined synthesis of a tunable SA to nanocluster electrocatalysts,disclosing the great potential of COFs in electrocatalysis.

关键词： carbon neutrality CO_(2)reduction reaction covalent organic framework nanocluster single atom

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The morphology of hydroxyapatite nanoparticles regulates clathrinmediated endocytosis in melanoma cells and resultant anti-tumor efficiency

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Nano research 2022年第7期15卷 6256-6265页

作者： Hongfeng Wu Yuchen Hua Jinjie Wu Qin Zeng Xiao Yang Xiangdong Zhu Xingdong Zhang National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China NMPA Key Laboratory for Quality Research and Control of Tissue Regenerative Biomaterials&Institute of Regulatory Science for Medical Devices&NMPA Research Base of Regulatory Science for Medical Devices Sichuan UniversityChengdu 610064China Research Center for Materials Genome Engineering Sichuan UniversityChengdu 610064China

Clathrin-mediated endocytosis plays a critical role for hydroxyapatite nanoparticles(HANPs)to enter tumor cells,induce mitochondrial apoptosis,and inhibit tumor *** study was aimed to investigate how the morphology of HANPs impacts the endocytosis of the particles in melanoma cells,and their anti-tumor effect by using in vitro cell experiments and in vivo tumor animal *** shapes of HANPs,including granular HANPs(G-HANPs),rod-like HANPs(R-HANPs),and needle-like HANPs(N-HANPs),were successfully prepared by wet chemical *** the three HANPs could be internalized into A375 melanoma cells as indicated by cellular transmission electron microscopy *** these HANPs,only G-HANPs induced morphological change of mitochondria and loss of mitochondrial membrane potential(Δψm),and exhibited the greatest intracellular internalization efficiency in the tumor ***,the results of immunofluorescence staining and western blotting indicated that the level of adaptin-2(AP2)protein was up-regulated by all the HANPs,and highest in G-HANPs treated A375 ***,in the tumor-bearing mouse model,we found that tumor growth was delayed by all the three HANPs,of which,G-HANPs delayed tumor growth most efficiently and presented a highest expression level of AP2 protein in tumor ***,this study suggested that the morphology of HANPs regulated their endocytosis efficiency and their effect to inhibit tumor *** work facilitates to direct the rational design of nano-materials for tumor therapy.

关键词： hydroxyapatite nanoparticles adaptin-2 protein morphology endocytosis anti-tumor effect

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Machine learning accelerated DFT research on platinum-modified amorphous alloy surface catalysts

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Chinese Chemical Letters 2023年第5期34卷 645-649页

作者： Xi Zhang Kangpu Li Bo Wen Jiang Ma Dongfeng Diao Institute of Nanosurface Science and Engineering Guangdong Provincial Key Laboratory of Micro/NanoShenzhen UniversityShenzhen 518060China College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China Research Center of Medical Plasma Technology Shenzhen UniversityShenzhen 518060China

Pt-modified amorphous alloy(Pt@PdNiCuP)catalyst exhibits excellent electro-catalytic activity and high experimental durability for hydrogen evolution reaction(HER).However,the physical origin of the catalytically active remains *** this paper,we constructed a distance contribution descriptor(DCD)for the feature engineering of machine learning(ML)potential,and calculated the Gibbs free energies(ΔGH)of 46,000*H binding sites on the Pt@Pd Ni Cu P surface by ML-accelerated density functional theory(DFT).The relationship betweenΔGHand DCD revealed that in the H-Pt distance region of 2.0-2.5 A where the parabolic tail and disordered scatters coexist,the H-metal bonding configuration is mainly the bridge-or hollow-bonding *** contribution analysis of DCD indicates that the joint effect of Pt,Pd and Ni atoms determines the catalytical behavior of amorphous alloy,which agrees well with experimental *** counting atomic percentages in different energy intervals,we obtained the atomic ratio for the best catalytic performance(Pt:Pd:Ni:Cu:P=0.33:0.17:0.155:0.16:0.185).Projected density of states(PDOS)show that H 1s orbital,Pt 5d orbital,and Pd 4d orbital form a bonding state at-2 e *** results provide new ideas for designing more active amorphous alloy catalysts.

关键词： Hydrogen evolution reaction Amorphous alloy Density functional theory Machine learning

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Power-Hardware-in-the-Loop Motor Emulator under Four-Quadrant Operation Condition 10

Power-Hardware-in-the-Loop Motor Emulator under Four-Quadran...

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10th IEEE International Power Electronics and Motion control Conference, IPEMC 2024 ECCE Asia

作者： Zhang, Gengchen Guo, Hong Xu, Jinquan Wang, Gaoxiang Zhang, Li Jin, Wenbo Zhao, Xiaopeng Liu, Ying Beihang University School of Automation Science and Electrical Engineering Bejing China Southwest China Research Institute of Electronic Equipment Chengdu China Xian Flight Automatic Control Research Institute Xi'an China National Key Laboratory of Science and Technology on Aircraft Control Xi'an China

ISBN: (纸本)9798350351330

In order to solve the problems of long cycle and the difficulty of test, this paper proposes a method of power-in-the-loop motor simulator. Firstly, the topology of the motor simulator is proposed, composed of an interface filtering unit, a motor simulation unit and an energy management unit. Secondly, a discretization method for permanent magnet synchronous motor(PMSM) is designed for DSP control. Thirdly, this paper proposes a method combining quasi-proportional resonance control(QPR) and direct current control to ensure the control accuracy. Finally, the motor simulator is verified by experiments. © 2024 IEEE.

关键词： Permanent magnets

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