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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 1039-1050页

作者： Chi ma Dianbiao Dong the School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China

This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown *** eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the *** addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader *** address this problem,a neural network state observer based on the leader state information is ***,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite ***,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm.

关键词： Finite-time control multi-agent systems neural network prescribed performance control time-varying formation control

Damping Characteristic Analysis and Optimization of Wind-thermal-bundled Power Transmission by LCC-HVDC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 299-312页

作者： Liwen Zheng Shiying ma the Power System Department China Electric Power Research InstituteBeijing 100192China

With the rapid development of renewable energy,wind-thermal-bundled power transmission by line-commutated converter based high-voltage direct current(LCC-HVDC)systems has been widely *** dynamic interaction mechanisms among permanent magnet synchronous generators(PMSGs),synchronous generators(SGs),and LCC-HVDC system become *** deal with this issue,a path analysis method(PAM)is proposed to study the dynamic interaction mechanism,and the damping reconstruction is used to analyze the damping characteristic of the ***,based on the modular modeling,linearized models for the PMSG subsystem,the LCC-HVDC subsystem,and the SG subsystem are ***,based on the closed-loop transfer function diagram of the system,the disturbance transfer path and coupling relationship among subsystems are analyzed by the PAM,and the damping characteristic analysis of the SG-dominated oscillation mode is studied based on the damping *** with the PAM,the small-signal model of the system is obtained and eigenvalue analysis results are ***,the effect of the control parameters on the damping characteristic is analyzed and the conclusions are verified by time-domain ***,the penalty functions of the oscillation modes and decay modes are taken as the objective function,and an optimization strategy based on the Monte Carlo method is proposed to solve the parameter optimization *** simulation results are presented to validate the effectiveness of the proposed strategy.

关键词： Wind-thermal-bundled power transmission line-commutated converter based high-voltage direct current(LCC-HVDC) path analysis method(PAM) damping characteristic analysis Monte Carlo method

非对称有限热源之间热机循环的基本热力学约束

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北京师范大学学报（自然科学版） 2023年第6期59卷 969-978页

作者：赵秀花涂展春马宇翰北京师范大学物理学系北京100875

为讨论更一般情形中有限热源之间的热力学约束,探讨了在2个具有非对称热容有限热源之间工作的热机循环问题.假定热源热容C满足德拜定律C∝T^(n),高低温热源不对称体现在它们关于温度(T)的幂指数(n)不同.对于通常的固体材料,n由材料的空... 详细信息

为讨论更一般情形中有限热源之间的热力学约束,探讨了在2个具有非对称热容有限热源之间工作的热机循环问题.假定热源热容C满足德拜定律C∝T^(n),高低温热源不对称体现在它们关于温度(T)的幂指数(n)不同.对于通常的固体材料,n由材料的空间维度和所处温度区间决定;在低温热源与高温热源初始热容比很大或很小的2个极限区域,证明了热机最大功率效率关于最大功效率的函数具有不依赖于热源维度的普适形式.在数值上探讨了2热源初始热容大小对称而热容(关于温度变化)行为不对称的特殊情况,结果显示,最大功效率和最大功率效率随高温热源维度的增大而升高,而关于低温热源维度变化的单调性则与低高温热源的初始温度比T_(L)/T_(H)有关.这一结果表明,若将有限热源的热容性质纳入其间热机循环的优化考量,则循环在低温端的优化方向(n在给定区间内的大小选择)要由热源初始温度所确定的卡诺效率η_(C)≡1-T_(L)/T_(H)决定.

关键词：热力学有限热源非对称热容有限时间热机最大功效率最大功率效率

Input-to-State Stability for Impulsive Switched Singular Systems with Mismatched Disturbances

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Journal of Systems Science & Complexity 2024年第3期37卷 924-946页

作者： YANG Anqing ma Shuping School of Information Engineering Shandong Management UniversityJinan 250357China School of mathematics Shandong UniversityJinan 250100China

This work investigates the input-to-state stability(ISS)problem for impulsive switched singular systems(ISSSs)with mismatched *** this paper,‘disturbance’is a general concept that includes model uncertainty,unknown system dynamic,external disturbance,*** modified uncertainty and disturbance estimator(UDE)-based control method is presented for singular systems and ISSSs,a virtual control is introduced to offset the effects of mismatched *** the basis of a discontinuous multiple Lyapunov functional and admissible edge-dependent average dwell time(AED-ADT)method,several sufficient conditions in terms of linear matrix inequalities(LMIs)are obtained to ensure that the closed-loop systems are regular,impulse-free and ***,two examples are given to demonstrate the effectiveness of the proposed results.

关键词： Impulsive switched singular systems input-to-state stability UDE-based control

“Unveiling the antiviral mechanism of Forsythia suspense: A comprehensive analysis of screening targets and components

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Journal of Chinese Pharmaceutical Sciences 2024年

作者： Na Sun Shuo ma Linxuan Jin Xin Zhang Miao Zhou Huanhuan Yang Wenqian Li Xinru Wu Yanyan Hou yuhan Yuan Yu Zhang Penghua Shu Food and Pharmacy College， Xuchang University

List of Supporting InformationTable S1 The PDB ID， Resolution， and ligand of key antiviral target p

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CD47在淋巴瘤治疗中的研究进展

白血病．淋巴瘤 2021年第5期30卷 314-317页

作者：马瑜晗桑威徐开林徐州医科大学血液病研究所徐州医科大学附属医院细胞研究和转化医学中心徐州医科大学附属医院血液科江苏徐州221000

CD47作为一种跨膜蛋白,广泛分布于多种细胞,通过与巨噬细胞上信号调节蛋白α(SIRPα)结合,释放抑制信号,逃避巨噬细胞的吞噬。淋巴瘤细胞CD47表达上调是诱导免疫逃逸的重要机制之一,也是潜在的治疗靶点。文章就CD47诱导的免疫逃逸、靶向... 详细信息

CD47作为一种跨膜蛋白,广泛分布于多种细胞,通过与巨噬细胞上信号调节蛋白α(SIRPα)结合,释放抑制信号,逃避巨噬细胞的吞噬。淋巴瘤细胞CD47表达上调是诱导免疫逃逸的重要机制之一,也是潜在的治疗靶点。文章就CD47诱导的免疫逃逸、靶向CD47的单克隆抗体和细胞免疫治疗等治疗手段在淋巴瘤治疗中的研究进展进行综述。

关键词：淋巴瘤 CD47 肿瘤逃逸免疫逃逸分子靶向治疗

Hydration lubrication modulated by water structure at TiO2–aqueous interfaces

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Friction 2024年第4期12卷 591-605页

作者： Pingsu ma Yuan LIU Ke HAN Yu TIAN Liran ma State Key Laboratory of Tribology in Advanced Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China

The nature of solid-liquid interfaces is of great significance in *** advances have been made in lubrication based on hydration ***,a detailed molecular-level understanding is still ***,we investigated water molecule behaviors at the TiO2-aqueous interfaces by the sum-frequency generation vibrational spectroscopy(SFG-VS)and atomic force microscope(AFM)to elucidate the fundamental role of solid-liquid interfaces in *** contributions of water structures and hydration effects were revealed,where water structures played the dominant role in lubrication for TiO2 surfaces of varying hydrophilicity,while hydration effects dominated with the increasing of ion *** lubrication is observed on the initial TiO2 surfaces with strongly H-bonded water molecules compared to the hydrophilic TiO2 surfaces with more disordered *** stable ordered water arrangement with strong hydrogen bonds and the shear plane occurring between the ordered water layer and subsequent water layer may play a significant role in achieving lower *** adsorbed hydrated molecules with the increasing ionic concentration perturb ordered water but lead to the enhancement of hydration effects,which is the main reason for the improved lubrication for both *** work provides more insights into the detailed molecular-level understanding of the mechanism of hydration lubrication.

关键词： hydration lubrication interfacial water structures hydration effects titanium dioxide(TiO2)

CToMP: a cycle-task-oriented memory protection scheme for unmanned systems

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Science China(Information Sciences) 2024年第6期67卷 399-417页

作者： Chengyan ma Ning XI Di LU Yebo FENG Jianfeng ma School of Cyber Engineering Xidian University School of Computer Science and Technology Xidian University Department of Computer and Information Science University of Oregon

Memory corruption attacks(MCAs) refer to malicious behaviors of system intruders that modify the contents of a memory location to disrupt the normal operation of computing systems, causing leakage of sensitive data or perturbations to ongoing processes. Unlike general-purpose systems, unmanned systems cannot deploy complete security protection schemes, due to their limitations in size, cost and *** in unmanned systems are particularly difficult to defend against. Furthermore, MCAs have diverse and unpredictable attack interfaces in unmanned systems, severely impacting digital and physical sectors. In this paper, we first generalize, model and taxonomize MCAs found in unmanned systems currently, laying the foundation for designing a portable and general defense approach. According to different attack mechanisms,we found that MCAs are mainly categorized into two types — return2libc and return2shellcode. To tackle return2libc attacks, we model the erratic operation of unmanned systems with cycles and then propose a cycle-task-oriented memory protection(CToMP) approach to protect control flows from tampering. To defend against return2shellcode attacks, we introduce a secure process stack with a randomized memory address by leveraging the memory pool to prevent Shellcode from being executed. Moreover, we discuss the mechanism by which CTo MP resists the return-oriented programming(ROP) attack, a novel variant of return2libc attacks. Finally, we implement CTo MP on CUAV V5+ with Ardupilot and Crazyflie. The evaluation and security analysis results demonstrate that the proposed approach CTo MP is resilient to various MCAs in unmanned systems with low footprints and system overhead.

关键词： unmanned system memory corruption attack memory protection system security randomized memory address

Aero-structural design of joined-wing aircraft based on high-fidelity model

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Chinese Journal of Aeronautics 2024年第4期37卷 363-377页

作者： Cheng HE Fengjiang ZHAN Luchuang ma Gang CHEN Jianying ma Unmanned Air Vehicle Research Institute Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Advanced Technology for Small and Medium-sized UAV Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China Aerospace System Engineering Shanghai Shanghai 201108China

The joined-wing configuration reduces induced drag and structural weight by connecting the rear wing to the front *** addition,the rear wing can replace the role of the horizontal tail of a conventional aircraft,thus eliminating the aerodynamic drag and weight associated with the horizontal *** particular shape creates a highly coupled relationship between aerodynamics and structure,which must be fully considered during the overall design process to enhance aircraft *** this research,an aero-structural design model of the joined-wing aircraft is constructed based on high-fidelity computational fluid dynamics and structural finite element *** model is able to obtain accurate aerodynamic loads for the non-planar wing and to simulate the statically indeterminate structure of the closed wing *** influence of the joined-wing shape parameters on the aerodynamic and structural disciplines,as well as the influence of geometric nonlinear characteristics,deformation constraints and buckling constraints on the structural weight are all taken into *** model is applied to complete the aero-structural design optimization of a high-altitude long-endurance joined-wing aircraft,and wind tunnel tests are *** test results verify the credibility of the design model proposed and the validity of the design environment.

关键词： Joined-wing configuration Aircraft design Aero-structural design Finite element Wind tunnel test

Capturing metal clusters at the strong-interaction region to reverse Ostwald ripening

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Science China materials 2024年第4期67卷 1363-1364页

作者： Shuheng Tian Ding ma Beijing National Laboratory for Molecular Sciences New Cornerstone Science LaboratoryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

High-temperature interactions induce sintering of metal nanoparticles(NPs) on heterogeneous catalyst surfaces, leading to reduced surface area and active site loss through Ostwald ripening [1]. This irreversible deactivation necessitates costly catalyst replacement, notably impacting metals like copper in hydrogenation and reforming reactions [2].

关键词： catalyst reforming irreversible