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Infrared microspectroscopy beamline BL06B at SSRF

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Nuclear Science and Techniques 2024年第1期35卷 10-17页

作者： Te Ji Hua-Chun Zhu Wei-Wei Peng jie Wang Hong-Wei zhao ai-Guo Li Min Chen Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China

The infrared microspectroscopy beamline(BL06B) is a phase Ⅱ beamline project at the Shanghai Synchrotron Radiation Facility(SSRF). The construction and optical alignment of BL06B were completed by the end of 2020. By 2021, it became accessible to users. The synchrotron radiation infrared(SRIR) source included edge radiation(ER) and bending magnet radiation(BMR). The extracted angles in the horizontal and vertical directions were 40 and 20 mrad, respectively. The photon flux, spectral resolution, and focused spot size were measured at the BL06B endstation, and the experimental results were consistent with theoretical calculations. SRIR light has a small divergence angle, high brightness, and a wide wavelength range. As a source of IR microscopy, it can easily focus on a diffraction-limited spatial resolution with a high signal-to-noise ratio(SNR). The BL06B endstation can be applied in a wide range of research fields, including materials, chemistry, biology, geophysics, and pharmacology.

关键词： Synchrotron radiation Infrared beamline Infrared microspectroscopy

A model reduction approach for discrete-time linear time-variant systems with delayed inputs

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Science China(Information Sciences) 2024年第4期67卷 197-217页

作者： ai-Guo WU Guang-Ren DUAN Yu WANG jie ZHANG School of Mechanical Engineering and Automation Harbin Institute of Technology(Shenzhen) HIT Wuhu Robot Technology Research Institute Center for Control Science and Technology Southern University of Science and Technology

A model reduction approach is presented for discrete-time linear time-variant input-delayed systems. According to this proposed approach, a dynamical variable is constructed by taking advantage of the current state and historical information of input. It is revealed that the behavior of this dynamical variable is governed by a discrete-time linear delay-free system. It is worth noting that the presented variable transformation does not require the system matrix to be invertible. Based on the reduced delay-free models,stabilizing control laws can be easily obtained for the original delayed system. For the case with a single input delay, the constructed variable is an exact prediction for the future state, and thus the stabilizing control law could be designed by replacing the future state with its prediction. Finally, three discrete-time periodic systems with delayed input are employed to illustrate how to utilize the presented model reduction approaches.

关键词： reduction approach predictor-based feedback time-varying systems delayed input periodic system

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Application of ultrasonic fatigue technology in very-high-cycle fatigue testing of aviation gas turbine engine blade materials:A review

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Science China(Technological Sciences) 2024年第5期67卷 1317-1363页

作者： zhao JiuCheng WAN jie ZHANG ShiZhong YAN ChuLiang zhao HongWei Key Laboratory of CNC Equipment Reliability Ministry of Education Jilin UniversityChangchun 130025China School of Mechanical&Aerospace Engineering Jilin UniversityChangchun 130025China Chongqing Research Institute of Jilin University Chongqing401120China School of Aeronautic Science and Engineering Beihang UniversityBeijing 102206China

The need for very-high-cycle fatigue(VHCF)testing up to 1010cycles of aviation gas turbine engine blade materials under combined mechanical loads and complex environments has encouraged the development of VHCF testing instrumentation and *** article begins with a comprehensive review of the existing available techniques that enable VHCF *** advances in ultrasonic fatigue testing(UFT)techniques are highlighted,containing their new capabilities and methods for single load,multiaxial load,variable amplitude fatigue,and combined cycle *** techniques for conducting UFT in high-temperature,humid environments,and corrosive environments are *** developments in mechanical loading and environmental building techniques provide the possibility of laboratory construction for real service conditions of blade *** techniques that can be used for in situ monitoring of VHCF damage are *** issues in the UFT field are presented,and countermeasures are ***,the existing problems and future trends in the field are briefly described.

关键词： aviation gas turbine engine blade materials ultrasonic fatigue very-high-cycle fatigue high-temperature complex stress in situ testing

Relativistic configuration-interaction density functional theory:Nonaxial effects on nuclear ββ decay

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Science Bulletin 2024年第13期69卷 2017-2020页

作者： Yakun Wang Pengwei zhao jie Meng State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China

Nuclear ββ decay is a second-order weak process in which an even-even nucleus decays to its neighboring even-even nucleus by turning two neutrons to two protons while emitting two electrons.A nucleus undergoes such ... 详细信息

关键词： decay neighboring interaction

Quaternion-Based Adaptive Trajectory Tracking Control of a Rotor-Missile with Unknown Parameters Identification

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Defence Technology（防务技术） 2024年第1期31卷 375-386页

作者： jie zhao Zhongjiao Shi Yuchen Wang Wei Wang Beijing Institute of Technology Beijing 100081China

This paper investigates the adaptive trajectory tracking control problem and the unknown parameter identification problem of a class of rotor-missiles with parametric system ***,considering the uncertainty of structural and aerodynamic parameters,the six-degree-of-freedom(6Do F) nonlinear equations describing the position and attitude dynamics of the rotor-missile are established,respectively,in the inertial and body-fixed reference ***,a hierarchical adaptive trajectory tracking controller that can guarantee closed-loop stability is proposed according to the cascade characteristics of the 6Do F ***,a memory-augmented update rule of unknown parameters is proposed by integrating all historical data of the regression *** long as the finitely excited condition is satisfied,the precise identification of unknown parameters can be ***,the validity of the proposed trajectory tracking controller and the parameter identification method is proved through Lyapunov stability theory and numerical simulations.

关键词： Rotor-missile Adaptive control Parameter identification Quaternion control

Global Phase Portraits of Uniform Isochronous Centers System of Degree Six with Polynomial Commutator

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 577-599页

作者： Li-na GUO ai-yong CHEN Shuai-feng zhao School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang 471023China Department of Mathematics Hunan First Normal UniversityChangsha 410205China School of Mechatronics Engineering Henan University of Science and TechnologyLuoyang 471023China

This paper studies the global phase portraits of uniform isochronous centers system of degree six with polynomial *** systems have the form x=-y+xf(x,y),y=x+yf(x,y),where f(x,y)=a_(1)x+a_(2)xy+a_(3)xy^(2)+a_(4)xy^(3)+a_(5)xy^(4)=xσ(y),and any zero of 1+a_(1)y+a_(2)y^(2)+a_(3)y^(3)+a_(4)y^(4)+a_(5)y^(5),y=y is an invariant straight *** last,all global phase portraits are drawn on the Poincare disk.

关键词： global phase portraits uniform isochronous center polynomial commutator invariant straight lines

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Performance Analysis and Optimization of Energy Harvesting Modulation for Multi-User Integrated Data and Energy Transfer

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China Communications 2024年第1期21卷 148-162页

作者： Yizhe zhao Yanliang Wu jie Hu Kun Yang School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

Integrated data and energy transfer(IDET)enables the electromagnetic waves to transmit wireless energy at the same time of data delivery for lowpower *** this paper,an energy harvesting modulation(EHM)assisted multi-user IDET system is studied,where all the received signals at the users are exploited for energy harvesting without the degradation of wireless data transfer(WDT)*** joint IDET performance is then analysed theoretically by conceiving a practical time-dependent wireless *** the aid of the AO based algorithm,the average effective data rate among users are maximized by ensuring the BER and the wireless energy transfer(WET)*** results validate and evaluate the IDET performance of the EHM assisted system,which also demonstrates that the optimal number of user clusters and IDET time slots should be allocated,in order to improve the WET and WDT performance.

关键词： energy harvesting modulation(EHM) integrated data and energy transfer(IDET) performance analysis wireless data transfer(WDT) wireless energy transfer(WET)

Reorientation and obstacle avoidance control of free-floating modular robots using sinusoidal oscillator

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Chinese Journal of Aeronautics 2024年第6期37卷 262-275页

作者： Zhiyuan YANG Mingzhu Lai Jian QI Ning zhao Xin SUI jie zhao Yanhe ZHU State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China School of Mathematics and Statistics Hainan Normal UniversityHaikou 571158China

This paper presents that a serpentine curve-based controller can solve locomotion control problems for articulated space robots with extensive flight phases,such as obstacle avoidance during free floating or attitude adjustment before *** proposed algorithm achieves articulated robots to use closed paths in the joint space to accomplish the above *** snakes,which can shuttle through gaps and adjust their landing posture by swinging their body during gliding in jungle environments,inspired the design of two *** first maneuver generates a rotation of the system by varying the moment of inertia between the joints of the robot,with the magnitude of the net rotation depending on the controller *** maneuver can be repeated to allow the robot to reach arbitrary *** second maneuver involves periodic undulations,allowing the robot to avoid collisions when the trajectory of the global Center of Mass(CM)passes through the *** maneuvers are based on the improved serpenoid curve,which can adapt to redundant systems consisting of different numbers of ***,the simulation illustrates that combining the two maneuvers can help a free-floating chain-type robot traverse complex *** proposed algorithm can be used with similar articulated robot models.

关键词： Collision avoidance Modularrobots Reorientation Free-floating space robots Nonholonomic systems Biologically inspired controllers Serpenoid curve

Distributed Stochastic Scheduling of Massive Backup Batteries in Cellular Networks for Operational Reserve and Frequency Support Ancillary Services

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 393-404页

作者： Kun Li Jiakun Fang Xiaomeng ai Shichang Cui Rongkang zhao Jinyu Wen State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China IEEE

Base station(BS)backup batteries(BSBBs),with their dispatchable capacity,are potential demand-side resources for future power *** enhance the power supply reliability and post-contingency frequency security of power systems,we propose a two-stage stochastic unit commitment(UC)model incorporating operational reserve and post-contingency frequency support provisions from massive BSBBs in cellular networks,in which the minimum backup energy demand is considered to ensure BS power supply *** energy,operational reserve,and frequency support ancillary services are co-optimized to handle the power balance and post-contingency frequency security in both forecasted and stochastic variable renewable energy(VRE)***,we propose a dedicated and scalable distributed optimization framework to enable autonomous optimizations for both dispatching center(DC)and *** BS model parameters are stored and processed locally,while only the values of BS decision variables are required to upload to DC under the proposed distributed optimization framework,which safeguards BS privacy *** studies on a modified IEEE 14-bus system demonstrate the effectiveness of the proposed method in promoting VRE accommodation,ensuring post-contingency frequency security,enhancing operational economics,and fully utilizing BSBBs'energy and power ***,the proposed distributed optimization framework has been validated to converge to a feasible solution with near-optimal performance within limited ***,numerical results on the Guangdong 500 kV provincial power system in China verify the scalability and practicality of the proposed distributed optimization framework.

关键词： Base station backup battery operational reserve frequency security distributed optimization privacy