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A high-precision multi-dimensional microspectroscopic technique for morphological and properties analysis of cancer cell

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Light(Science & Applications) 2023年第6期12卷 1117-1126页

作者： Lirong Qiu Yunhao Su Ke-Mi Xu Han Cui Dezhi Zheng Yuanmin Zhu Lin Li Fang Li Weiqian Zhao MIIT Key Laboratory of Complex-field Intelligent Exploration School of Optics and PhotonicsBeijing Institute of Technology100081 BeijingChina department of Gastroenterology Aerospace Central HospitalPeking University Aerospace School of Clinical Medicine100081 BeijingChina department of Pathology Aerospace Central HospitalPeking University Aerospace School of Clinical Medicine100081 BeijingChina

Raman and Brillouin scattering are sensitive approaches to detect chemical composition and mechanical elasticity pathology of cells in cancer development and their medical treatment *** application is,however,suffering from the lack of ability to synchronously acquire the scattering signals following three-dimensional(3D)cell morphology with reasonable spatial resolution and signal-to-noise ***,we propose a divided-aperture laser differential confocal 3D Geometry-Raman-Brillouin microscopic detection technology,by which reflection,Raman,and Brillouin scattering signals are simultaneously in situ collected in real time with an axial focusing accuracy up to 1 nm,in the height range of 200μ*** divided aperture improves the anti-noise capability of the system,and the noise influence depth of Raman detection reduces by 35.4%,and the Brillouin extinction ratio increases by 22 dB.A high-precision multichannel microspectroscopic system containing these functions is developed,which is utilized to study gastric cancer *** a result,a 25%reduction of collagen concentration,42%increase of DNA substances,17%and 9%decrease in viscosity and elasticity are finely resolved from the 3D *** findings indicate that our system can be a powerful tool to study cancer development new therapies at the sub-cell level.

关键词： elasticity dimensional spectroscopic

Affine formation maneuver tracking control of multiple second-order agents with time-varying delays

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Science China(Technological Sciences) 2019年第4期62卷 665-676页

作者： XU Yang LI DongYu LUO DeLin YOU YanCheng School of aerospace Engineering Xiamen University department of Electrical and Computer Engineering National University of Singapore department of Control Science and Engineering Harbin Institute of Technology

This paper considers an affine maneuver tracking control problem for leader-follower type second-order multi-agent systems in the presence of time-varying delays, where the interaction topology is directed. Using the property of the affine transformation,this paper gives the sufficient and necessary conditions of achieving the affine localizability and extends it to the second-order condition. Under the(n + 1)-reachable condition of the given n-dimensional nominal formation with n + 1 leaders, a formation of agents can be reshaped in arbitrary dimension by only controlling these leaders. When the neighboring positions and velocities are available, a formation maneuver tracking control protocol with time-varying delays is constructed with the form of linear systems, where the tracking errors of the followers can be specified. Based on Lyapunov-Krasovskii stability theory, sufficient conditions to realize affine maneuvers are proposed and proved, and the unknown control gain matrix can be solved only by four linear matrix inequalities independent of the number of agents. Finally, corresponding simulations are carried out to verify the theoretical results, which show that these followers can track the time-varying references accurately and continuously.

关键词： formation control affine transformation multi-agent systems second-order dynamics time-varying delays

Correction to:Practical framework for data-driven RANS modeling with data augmentation

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Acta Mechanica Sinica 2021年第12期37卷 1840-1842页

作者： Xianwen Guo Zhenhua Xia Shiyi Chen State Key Laboratory for Turbulence and Complex systems College of EngineeringPeking UniversityBeijing 100871China department of Engineering Mechanics Zhejiang UniversityHangzhou 310027China department of Mechanics and aerospace Engineering Southern University of Science and TechnologyShenzhen 518055China

Correction to:Acta Mechanica Sinica(2021)37(12):1750-1758 https://***/10.1007/s10409-021-01147-2 In the original publication,the last equation in Eq.(8)should be.

关键词： Practical Correction modeling

Differential game strategy in three-player evasion and pursuit scenarios

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Journal of systems Engineering and Electronics 2018年第2期29卷 352-366页

作者： SUN Qilong QI Naiming XIAO Longxu LIN Haiqi department of aerospace Engineering Harbin Institute of TechnologyHarbin 150001China The Rocket Force Equipment Academy Beijing 100096China

A conflict of three players, including an attacker, a defender, and a target with bounded control is discussed based on the differential game theories in which the target and the defender use an optimal pursuit strategy. The current approach chooses the miss distance as the outcome of the conflict. Different optimal guidance laws are investigated, and feasible conditions are analyzed for the attacker to accomplish an attacking task. For some given conditions, the attacker cannot intercept the target by only using a one-to-one optimal pursuit guidance law; thus, a guidance law for the attacker to reach a critical safe value is ***, the guidance law is divided into two parts. Before the engagement time between the defender and the attacker, the attacker uses this derived guidance law to guarantee that the evasion distance from the defender is safe, and that the zero-effort-miss(ZEM) distance between the attacker and the target is the *** that engagement time, the attacker uses the optimal one-toone guidance law to accomplish the pursuit task. The advantages and limited conditions of these derived guidance laws are also investigated by using nonlinear simulations.

关键词： three players differential game theory zero-effort-miss(ZEM) distance guidance law

Robust control approach for handling matched and/or unmatched uncertainties in port-controlled Hamiltonian systems

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IET Cyber-systems and Robotics 2019年第3期1卷 73-80页

作者： Tahereh Binazadeh Mahsa Karimi Ali Reza Tavakolpour-Saleh department of Electrical and Electronic Engineering Shiraz University of TechnologyShirazIran department of Mechanical and aerospace Engineering Shiraz University of TechnologyShirazIran

This study considers the problem of robust interconnection and damping assignment passivity-based control approach(IDA-PBC)for underactuated mechanical systems from two points of ***,the robustness of IDA-PBC in the presence of non-vanishing matched and unmatched uncertainties is analysed and sufficient conditions are derived to ensure ultimate boundedness of ***,the robust control design is provided by adding a new control input to the former controller designed by IDA-PBC,such that asymptotic stability of the closed-loop system in the face of non-vanishing matched uncertainties is ***,the proposed robust controller is evaluated through simulations of two practical examples,*** inertia wheel pendulum and a single-link elastic joint *** simulation outcomes clearly reveal the effectiveness of the presented robust controller.

关键词： matched vanishing Hamiltonian

Modularity,reconfigurability,and autonomy for the future in spacecraft:A review

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Chinese Journal of Aeronautics 2023年第7期36卷 282-315页

作者： Zhibin ZHANG Xinhong LI Yanyan LI Gangxuan HU Xun WANG Guohui ZHANG Haicheng TAO Space Engineering University Beijing 101416China department of aerospace Science and technology Space Engineering UniversityBeijing 101416China

The shape of a spacecraft is transitioning from monolithic,manual,and static to modular,autonomous,and *** Reconfigurable Spacecrafts(MRSs)offer better solutions than traditional monolithic spacecrafts in several aspects,and may become the next generation of spacecraft systems with efficient design,fast deployment,flexible application,and convenient *** paper reviews the development and technology of MRS from three aspects:Modularity,reconfigurability,and *** the progress of research on MRS,there is still a lack of unified standards and little understanding of related *** on the understanding of basic concepts,the studies conducted on MRS are reviewed to identify technical requirements and *** at the future development trend of MRS,a novel modular selfreconfigurable spacecraft,referred to as MagicSat,is ***,the MagicSat system composition,advantages,and application prospects are *** enabling technologies and major challenges of MRS are further analyzed in terms of modularization,integrated management,and self-reconfiguration ***,the future development trend of MRS technology is predicted,and corresponding suggestions are provided.

关键词： Autonomous Deformable Modular Reconfigurable Spacecraft(MRS) Modular Self-Reconfigurable Spacecraft(MSRS) On-Orbit Service(OOS) Self-reconfiguration

Photoelectron longitudinal momentum distributions containing nondipole effects

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Chinese Physics B 2018年第1期27卷 335-340页

作者：霍一宁李健马凤才 School of Physics Liaoning University department of Physics Shenyang Aerospace University School of Physics Science and technology Inner Mongolia University

This paper proposes a modified strong field approximation model for evaluating nondipole effects on the ionization of an atom in an intense laser field. The photoelectron longitudinal momentum distributions （PLMD） of a hydrogen-like atom exposed to a mid-infrared laser field is calculated. The theoretical results indicate an obvious asymmetry in the PLMD, and an offset of the PLMD peak appears in the opposite direction of the beam propagation due to nondipole effects. The peak offsets of the PLMD increased with the laser intensity, imposed by the initial state of the hydrogen-like atom.

关键词： strong field approximation photoelectron longitudinal momentum distributions nondipole effects

Atomic-scale simulations for lithium dendrite growth driven by strain gradient

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Applied Mathematics and Mechanics(English Edition) 2020年第4期41卷 533-542页

作者： Gao XU Feng HAO Jiawang HONG Daining FANG State Key Laboratory for Turbulence and Complex systems&Center for Applied Physics and technology College of EngineeringPeking UniversityBeijing 100871China department of Engineering Mechanics Shandong UniversityJinan 250100China School of aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Institute of Advanced Structure technology Beijing Institute of TechnologyBeijing 100081China

Dendrite formation is a major obstacle, e.g., capacity loss and short circuit,to the next-generation high-energy-density lithium(Li)-metal batteries. The development of successful Li dendrite mitigation strategies is impeded by an insu?cient understanding in Li dendrite growth mechanisms. The Li-plating-induced internal stress in Li-metal and its e?ects on dendrite growth have been widely studied, but the underlying microcosmic mechanism is elusive. In the present study, the role of the plating-induced stress in dendrite formation is analyzed through ?rst-principles calculations and ab initio molecular dynamic(AIMD) simulations. It is shown that the deposited Li forms a stable atomic nano?lm structure on the copper(Cu) substrate, and the adsorption energy of Li atoms increases from the Li-Cu interface to the deposited Li surface, leading to more aggregated Li atoms at the interface. Compared with the pristine Li-metal, the deposited Li in the early stage becomes compacted and su?ers the in-plane compressive stress. Interestingly,there is a giant strain gradient distribution from the Li-Cu interface to the deposited Li surface, making the deposited atoms adjacent to the Cu surface tend to press upwards with perturbation and causing the dendrite growth. This provides an insight into the atomicscale origin of Li dendrite growth, and may be useful for suppressing the Li dendrite in Li-metal-based rechargeable batteries.

关键词： lithium(Li)-metal-based battery Li dendrite strain gradient depositing

Stability analysis of constrained MPC with CLF applied to discrete-time nonlinear system

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Science China(Information Sciences) 2014年第11期57卷 186-194页

作者： RUAN XiaoGang HOU XuYang MA HangYing department of Electronic Information and Control Engineering Beijing University of Technology Beijing aerospace Control Instrument Research Institute

The model predictive control(MPC) strategy with a control Lyapunov function(CLF) as terminal cost is commonly used for its guaranteed stability. In most of the cases, CLF is locally designed, and the region of attraction is limited, especially when under control constraints. In this article, the stability and the region of attraction of constrained MPC that is applied to the discrete-time nonlinear system are explicitly *** region of feasibility is proposed to substitute the region of attraction, which greatly reduces the calculation burden of terminal constraints inequalities and guarantees the stability of the MPC algorithm. Also, the timevariant terminal weighted factor is proposed to improve the dynamic performance of the close-loop *** experiments verify the effectiveness and feasibility of the relative conclusions, which provide practically feasible ways to stabilize the unstable and/or fast-dynamic systems.

关键词： constrained MPC stability analysis discrete-time system control Lyapunov function region of attraction