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Science China(Technological Sciences) 2024年第6期67卷 1893-1906页

作者： AN Kai WANG ZhenGuo HUANG Wei Hypersonic technology Laboratory National University of Defense TechnologyChangsha410073China

We propose an adaptive learning-based optimal control scheme for height-velocity control models considering model uncertainties and external disturbances of hypersonic winged-cone *** longitudinal nonlinear model is first established and transformed into the control-oriented error equations,and the control scheme is organized by a steady-compensation *** overcome and eliminate the impact of model uncertainties and external disturbances,an adaptive radial basis function neural network(RBFNN)is designed by a q-gradient *** the height-velocity error system with estimated uncertainties into account,the adaptive learning-based optimal tracking control(ALOTC)scheme is proposed by combining the critic-only adaptive dynamic programming(ADP)framework and parameter optimization of system settling ***,a novel weight update law is proposed to satisfy the online iteration requirements,and the algorithm convergence and closedloop stability are discussed by the Lyapunov ***,four simulation cases are provided to prove the effectiveness,accuracy,and robustness of the proposed scheme for the hypersonic longitudinal control system.

关键词： optimal tracking control adaptive dynamic programming RBFNN hypersonic vehicle

Bio-inspired Design and Inverse Kinematics Solution of an Omnidirectional Humanoid Robotic Arm with Geometric and Load Capacity Constraints

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Journal of Bionic Engineering 2024年第2期21卷 778-802页

作者： Zhichao Zhu Zirong Luo Yiming Zhu Tao Jiang Minghai Xia Shanjun Chen Boyu Jin College of Intelligence Science and technology National University of Defense TechnologyChangshaChina

Inspired by the driving muscles of the human arm,a 4-Degree of Freedom(DOF)concentrated driving humanoid robotic arm is proposed based on a spatial double parallel four-bar *** four-bar mechanism design reduces the inertia of the elbow-driving unit and the torque by 76.65%and 57.81%,*** the human pose regulation strategy that the human arm picks up a heavy object by adjusting its posture naturally without complicated control,the robotic arm features an integrated position-level closed-form inverse solution method considering both geometric and load capacity *** method consists of a geometric constraint model incorporating the arm angle(φ)and the Global Configuration(GC)to avoid joint limits and singularities,and a load capacity model to constrain the feasible domain of the arm ***,trajectory tracking simulations and experiments are conducted to validate the feasibility of the proposed inverse solution *** simulated maximum output torque,maximum output power and total energy consumption of the robotic arm are reduced by up to 2.0%,13.3%,and 33.3%,*** experimental results demonstrate that the robotic arm can bear heavy loads in a human-like posture,effectively reducing the maximum output torque and energy consumption of the robotic arm by 1.83%and 5.03%,respectively,while avoiding joints beyond geometric and load capacity *** proposed design provides a high payload–weight ratio and an efficient pose control solution for robotic arms,which can potentially broaden the application spectrum of humanoid robots.

关键词： Humanoid robotic arm Bio-inspired design Inverse kinematics solution Load capacity constraint Geometric constraint

Drag reduction characteristics of recirculation flow at rocket base in an RBCC engine under ramjet/scramjet mode

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Chinese Journal of Aeronautics 2024年第3期37卷 104-115页

作者： Menglei LI Mingbo SUN Peibo LI Daoning YANG Bin AN Yizhi YAO Jikai CHEN Taiyu WANG Jiaoru WANG Hypersonic technology Laboratory National University of Defense TechnologyChangsha 410073China Department of Aerospace Science and technology Space Engineering UniversityBeijing 101416China

To reduce the drag generated by the recirculation flow at the rocket base in a RocketBased Combined Cycle(RBCC)engine operating in the ramjet/scramjet mode,a novel annular rocket RBCC engine based on a central plug cone was *** performance loss mechanism caused by the recirculation flow at the rocket base and the influence of the plug cone configuration on the thrust performance were *** indicated that the recirculation flow at the rocket base extended through the entire combustor,which creates an extensive range of the"low-kineticenergy zone"at the center and leads to an engine thrust *** plug cone serving as a surface structure had a restrictive effect on the internal flow of the engine,making it smoothly transit at the position of the large separation *** model RBCC engine could achieve a maximum thrust augmentation of 37.6%with a long plug cone that was twice diameter of the inner ***,a shorter plug cone that was half diameter of the inner isolator proved less effective at reducing the recirculation flow for a supersonic flow and induced an undesirable flow fraction that diminished the thrust ***,the effectiveness of the plug cone increased with the flight Mach number,indicating that it could further broaden the operating speed range of the scramjet mode.

关键词： Rocket-based combined cycle Ramjet/scramjet mode Plug cone Drag reduction k-x SST turbulent model

Effect of strain on structure and electronic properties of monolayer C_(4)N_(4)

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Chinese Physics B 2024年第5期33卷 595-600页

作者：陈昊徐瑛赵家石周丹 School of Physics Changchun University of Science and TechnologyChangchun 130022China School of Computer Science and technology Changchun University of Science and TechnologyChangchun 130022China

The first-principles calculations are performed to examine structural,mechanical,and electronic properties at large strain for a monolayer C_(4)N_(4),which has been predicted as an anchoring promising material to attenuate shuttle effect in Li–S batteries stemming from its large absorption energy and low diffusion energy *** results show that the ideal strengths of C_(4)N_(4)under tension and pure shear deformation conditions reach 13.9 GPa and 12.5 GPa when the strains are 0.07 and 0.28,*** folded five-membered rings and diverse bonding modes between carbon and nitrogen atoms enhance the ability to resist plastic deformation of C_(4)N_(4).The orderly bond-rearranging behaviors under the weak tensile loading path along the[100]direction cause the impressive semiconductor–metal transition and inverse semiconductor–metal *** present results enrich the knowledge of the structure and electronic properties of C_(4)N_(4)under deformations and shed light on exploring other two-dimensional materials under diverse loading conditions.

关键词： two-dimensional materials strain effect structural evolution electronic properties

Mode-dependent dynamic gain of all-fiber FM-EDFA under various pump manipulation

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Chinese Optics Letters 2024年第2期22卷 128-134页

作者：方翼鸿张心怡黄锡恒曾研许鸥李建平付松年秦玉文 Institute of Advanced Photonics technology School of Information EngineeringGuangdong University of TechnologyGuangzhou 510006China Guangdong Provincial Key Laboratory of Information Photonics technology Guangdong University of TechnologyGuangzhou 510006China Key Laboratory of Photonic technology for Integrated Sensing and Communication Ministry of EducationGuangdong University of TechnologyGuangzhou 510006China

The dynamic gain of a few-mode erbium-doped fiber amplifier(FM-EDFA)is vital for the long-haul mode division multiplexing(MDM)***,we investigate the mode-dependent dynamic gain of an FM-EDFA under various manipulations of the pump ***,we numerically calculate the gain variation with respect to the input signal power,where a modedependent saturation input power occurs under different pump *** under the fixed intensity profile of the pump laser,the saturation input power of each spatial mode is ***,high-order mode pumping leads to a compression of the linear amplification region,even though it is beneficial for the mitigation of the differential modal gain(DMG)arising in all guided ***,we develop an all-fiber 3-mode EDFA,where the fundamental mode of the pump laser can be efficiently converted to the LP_(11)mode using the all-fiber mode-selective coupler(MSC).In comparison with the traditional LP_(01)pumping scheme,the DMG at 1550 nm can be mitigated from 1.61 dB to 0.97 dB under the LP_(11)mode pumping,while both an average gain of 19.93 dB and a DMG of less than 1 dB can be achieved from 1530 nm to 1560 ***,the corresponding signal input saturation powers are reduced by 0.3 dB for the LP_(01)mode and 1.6 dB for the LP_(11)mode,*** theoretical and experimental results indicate that a trade-off occurs between the DMG mitigation and the extension of the linear amplification range when the intensity profile of pump laser is manipulated.

关键词： few-mode erbium-doped fiber amplifier differential modal gain saturation input power

Vector field path following for a micro flapping-wing robot

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Science China(Information Sciences) 2024年第6期67卷 442-444页

作者： Haifeng HUANG Yingte LIU Tao NIU Chang WANG Yao ZOU Wei HE School of Intelligence Science and technology University of Science and Technology Beijing Institute of Artificial Intelligence University of Science and Technology Beijing Key Laboratory of Intelligent Bionic Unmanned Systems Ministry of EducationUniversity of Science and Technology Beijing

Flapping-wing robots mimic the flight patterns of natural flying creatures,granting them natural *** hold promising applications in the military reconnaissance,urban surveillance,and various other fields[1–3].However,the current limitations in size often restrict the suitability of existing bird-like flapping-wing robots,

关键词：

Glibenclamide pretreatment attenuates early hematoma expansion of warfarin-associated intracerebral hemorrhage in rats by alleviating perihematomal blood-brain barrier dysfunction

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Chinese Neurosurgical Journal 2024年第1期10卷 8-19页

作者： Zongwei Zeng Liang Liang Zhou Feng Peiwen Guo Xiaoke Hao Jishu Xian Hua Feng Yujie Chen Zhi Chen Department of Neurosurgery and State Key Laboratory of Trauma Burn and Combined InjurySouthwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China Department of Neurosurgery The 945Th Hospital of PLAYaanSichuan Province 625099China Department of Rehabilitation Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China Chongqing Key Laboratory of Precision Neuromedicine and Neuroregeneration Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China Chongqing Clinical Research Center for Neurosurgery Southwest HospitalThird Military Medical University(Army Medical University)Chongqing 400038China

Background Hematoma expansion is a determinant of poor outcome of intracerebral hemorrhage but occurs frequently,especially in warfarin-associated intracerebral hemorrhage(W-ICH).In the present study,we employ the warfarin-associated intracerebral hemorrhage(W-ICH)rat model,to explore the efficacy and potential mechanism of glibenclamide pretreatment on hematoma expansion after intracerebral hemorrhage,hoping to provide proof of concept that glibenclamide in stroke primary and secondary prevention is also potentially beneficial for intracerebral hemorrhage patients at early *** In the present study,we tested whether glibenclamide,a common hypoglycemic drug,could attenuate hematoma expansion in a rat model of *** expansion was evaluated using magnetic resonance imaging;brain injury was evaluated by brain edema and neuronal death;and functional outcome was evaluated by neurological *** blood-brain barrier integrity was assessed using Evans blue extravasation and tight junction-related *** The data indicated that glibenclamide pretreatment significantly attenuated hematoma expansion at 24 h after W-ICH,thus mitigating brain edema and neuronal death and promoting neurological function recovery,which may benefit from alleviating blood-brain barrier disruption by suppressing matrix *** The results indicate that glibenclamide pretreatment in stroke primary and secondary prevention might be a promising therapy for hematoma expansion at the early stage of W-ICH.

关键词： Intracerebral hemorrhage Warfarin Glibenclamide Hematoma expansion Blood-brain barrier Matrix metallopeptidase-9

An Intelligent Framework for Resilience Recovery of FANETs with Spatio-Temporal Aggregation and Multi-Head Attention Mechanism

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Computers, Materials & Continua 2024年第5期79卷 2375-2398页

作者： Zhijun Guo Yun Sun YingWang Chaoqi Fu Jilong Zhong Air Traffic Control and Navigation College Air Force Engineering UniversityXi’an710000China Institute of Systems Engineering Academy of Military ScienceBeijing100101China Equipment Management and UAV Engineering College Air Force Engineering UniversityXi’an710038China Defense Innovation Institute Academy of Military ScienceBeijing100071China

Due to the time-varying topology and possible disturbances in a conflict environment,it is still challenging to maintain the mission performance of flying Ad hoc networks(FANET),which limits the application of Unmanned Aerial Vehicle(UAV)swarms in harsh *** paper proposes an intelligent framework to quickly recover the cooperative coveragemission by aggregating the historical spatio-temporal network with the attention *** mission resilience metric is introduced in conjunction with connectivity and coverage status information to simplify the optimization model.A spatio-temporal node pooling method is proposed to ensure all node location features can be updated after destruction by capturing the temporal network *** with the corresponding Laplacian matrix as the hyperparameter,a recovery algorithm based on the multi-head attention graph network is designed to achieve rapid *** results showed that the proposed framework can facilitate rapid recovery of the connectivity and coverage more effectively compared to the existing *** results demonstrate that the average connectivity and coverage results is improved by 17.92%and 16.96%,respectively compared with the state-of-the-art ***,by the ablation study,the contributions of each different improvement are *** proposed model can be used to support resilient network design for real-time mission execution.

关键词： Resilience cooperative mission FANET spatio-temporal node pooling multi-head attention graph network

Cancer stem cell-immune cell crosstalk in the tumor microenvironment for liver cancer progression

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Frontiers of Medicine 2024年第3期18卷 430-445页

作者： Yue Ma Hongwei Lv Fuxue Xing Wei Xiang Zixin Wu Qiyu Feng Hongyang Wang Wen Yang Cancer Research Center First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei230027China National Center for Liver Cancer Naval Medical University(Second Military Medical University)Shanghai201805China International Co-operation Laboratory on Signal Transduction Eastern Hepatobiliary Surgery HospitalNaval Medical University(Second Military Medical University)Shanghai200438China Shanghai Key Laboratory of Hepato-biliary Tumor Biology Shanghai200438China Key Laboratory of Signaling Regulation and Targeting Therapy of Liver Cancer Ministry of EducationShanghai200438China

Crosstalk between cancer cells and the immune microenvironment is determinant for liver cancer progression.A tumor subpopulation called liver cancer stem cells(CSCs)significantly accounts for the initiation,metastasis,therapeutic resistance,and recurrence of liver *** evidence demonstrates that the interaction between liver CSCs and immune cells plays a crucial role in shaping an immunosuppressive microenvironment and determining immunotherapy *** review sheds light on the bidirectional crosstalk between liver CSCs and immune cells for liver cancer progression,as well as the underlying molecular mechanisms after presenting an overview of liver CSCs characteristic and their ***,we discuss the potential application of liver CSCs-targeted immunotherapy for liver cancer treatment.

关键词： liver cancer cancer stem cell immune cell immunotherapy

Evaluating the Compatibility Mechanism of Shengxian Decoction Based on an Excretion Study of 18 Bioactive Constituents in Rat Biosamples

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World Journal of Traditional Chinese Medicine 2024年第1期10卷 40-52页

作者： Tao Pang Nan Weng Yong Chen Cui-Yun Huang Mei Sun Feng Zhang Wan-Sheng Chen Department of Pharmacy Changzheng HospitalNaval Medical University(Second Military Medical University)ShanghaiChina Department of Pharmacognosy Shenyang Pharmaceutical university ShenyangLiaoning ProvinceChina Traditional Chinese Medicine Resource and technology Center Shanghai University of Traditional Chinese MedicineShanghaiChina

Introduction:The Shengxian decoction(SXT),a Chinese herbal medication used to treat heart failure,is composed of Astragali Radix,Anemarrhenae Rhizoma,Bupleuri Radix,Cimicifuage Rhizoma,and Platycodonis *** of the excretion of the active compounds in this herbal medication is vital for investigating the underlying mechanisms behind its ***,this remains ***:Liquid chromatography coupled with mass spectrometry was performed in both positive and negative modes to assay 18 constituents of SXT from rat urinary,fecal,and biliary ***:The methodology was validated and showed good linearity(r≥0.9),precision,stability,repeatability,and *** relative standard deviations and relative errors for the precision and accuracy did not exceed 15%.The recoveries of all the compounds ranged from 77.37%to 114.82%,and the matrix effect was between 82.53%and 105.71%.The results suggested that,when combined with Platycodonis Radix,the levels of 14 constituents from the four herbs were reduced in the urine,while the levels of six constituents were reduced in the ***:The comparative excretion results indicated that Platycodonis Radix reduced the excretion of compounds in SXT,demonstrating the compatibility mechanism and holistic properties of these compounds,favoring the pharmacological effects of SXT.

关键词： Compatibility excretion liquid chromatography coupled with mass spectrometry Platycodonis Radix Shengxian decoction