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Extremum seeking control for UAV close formation flight via improved pigeon-inspired optimization

science China(Technological sciences) 2024年第2期67卷 435-448页

作者： YUAN GuangSong DUAN HaiBin State Key Laboratory of Virtual Reality Technology and Systems School of Automation Science and Electrical EngineeringBeihang University(BUAA)Beijing 100083China

This paper proposes a comprehensive design scheme for the extremum seeking control(ESC)of the unmanned aerial vehicle(UAV)close formation *** proposed design scheme combines a Newton-Raphson method with an extended Kalman filter(EKF)to dynamically estimate the optimal position of the following UAV relative to the leading *** reflect the wake vortex effects reliably,the drag coefficient induced by the wake vortex is considered as a performance ***,the performance function is parameterized by the first-order and second-order terms of its Taylor series *** the excellent performance of nonlinear estimation,the EKF is used to estimate the gradient and the Hessian matrix of the parameterized performance *** output feedback of the proposed scheme is determined by iterative calculation of the Newton-Raphson *** with the traditional ESC and the classic ESC,the proposed design scheme avoids the slow continuous time integration of the *** allows a faster convergence of relative position ***,the proposed method can provide a smoother command during the seeking process as the second-order term of the performance function is taken into *** convergence analysis of the proposed design scheme is accomplished by showing that the output feedback is a supermartingale *** improve estimation performance of the EKF,a improved pigeon-inspired optimization(IPIO)is proposed to automatically tune the noise covariance *** Carlo simulations for a three-UAV close formation show that the proposed design scheme is robust to the initial position of the following UAV.

关键词： unmanned aerial vehicle close formation extremum seeking control Newton-Raphson method improved pigeon-inspired optimization

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Weighted sum power maximization for STAR-RIS-aided SWIPT systems with nonlinear energy harvesting

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science China(information sciences) 2024年第10期67卷 343-358页

作者： Weiping SHI Cunhua PAN Feng SHU Yongpeng WU Jiangzhou WANG Yongqiang BAO Jin TIAN School of Network and Communication Nanjing Vocational College of Information Technology National Mobile Communications Research Laboratory Southeast University School of Information and Communication Engineering Hainan University School of Electronic and Optical Engineering Nanjing University of Science and Technology Shanghai Key Laboratory of Navigation and Location Based Services Shanghai Jiao Tong University School of Engineering University of Kent School of Information and Communication Engineering Nanjing Institute of Technology Engineering School of Networks and Telecommunications Jinling Institute of Technology

The conventional reconfigurable intelligent surface(RIS) is limited to reflecting incident signals,thereby imposing constraints on the placement of the transmitter and receiver, which hinders achieving comprehensive signal coverage across an entire area. This paper investigates a simultaneously transmitting and reflecting(STAR)-RIS-aided simultaneous wireless information and power transfer(SWIPT) system with a nonlinear energy harvesting model under three different RIS transmission protocols: energy splitting(ES),time switching(TS), and mode switching(MS). The objective of this paper is to maximize the weighted sum power(WSP) of all energy harvesting receivers(EHRs) while ensuring fairness in the collected power among them. This is achieved by jointly optimizing the transmit beamforming at the base station(BS)and the transmission and reflection coefficients at the STAR-RIS, subject to rate constraints for information decoding receivers(IDRs), transmit power constraint at the BS, and coefficient constraints of each element at the STAR-RIS corresponding to the three protocols. Solving this optimization problem poses challenges because of the complicated objective function and numerous coupled optimization variables of the ES STAR-RIS. To address this complexity, an efficient alternating optimization(AO) approach is proposed as an iterative solution method that achieves suboptimal results. The AO algorithm is then extended to MS STAR-RIS and TS STAR-RIS. Specifically, for MS STRA-RIS, binary constraints in the STAR-RIS coefficient optimization subproblem are handled using the first-order approximation technique along with the penalty function method. For TS STAR-RIS, apart from optimizing BS transmit beamforming and STAR-RIS coefficients subproblems, the transmission and reflection time allocation of STAR-RIS also needs *** findings demonstrate that compared to conventional RIS-aided systems, utilizing three different protocols in a STAR-RIS-aided sy

关键词： STAR-RIS beamforming SWIPT alternating optimization nonlinear energy harvesting

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Fuzzing:Progress,Challenges,and Perspectives

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Computers, Materials & Continua 2024年第1期78卷 1-29页

作者： Zhenhua Yu Zhengqi Liu Xuya Cong Xiaobo Li Li Yin Institute of Systems Security and Control College of Computer Science and TechnologyXi'an University of Science and TechnologyXi'an710054China School of Mathematics and Information Science Baoji University of Arts and SciencesBaoji721013China Institute of Systems Engineering Macao University of Science and TechnologyTaipaMacaoChina

As one of the most effective techniques for finding software vulnerabilities,fuzzing has become a hot topic in software *** feeds potentially syntactically or semantically malformed test data to a target program to mine vulnerabilities and crash the *** recent years,considerable efforts have been dedicated by researchers and practitioners towards improving fuzzing,so there aremore and more methods and forms,whichmake it difficult to have a comprehensive understanding of the *** paper conducts a thorough survey of fuzzing,focusing on its general process,classification,common application scenarios,and some state-of-the-art techniques that have been introduced to improve its ***,this paper puts forward key research challenges and proposes possible future research directions that may provide new insights for researchers.

关键词： Fuzzing vulnerability software testing software security

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Clipping discrete multi-tone for peak-power-constraint IM/DD optical systems

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science China(information sciences) 2023年第5期66卷 227-237页

作者： Ji ZHOU Liangchuan LI Jiale HE Xiaofeng LU Yu BO Guanyu WANG Yuanda HUANG Gengchen LIU Yanzhao LU Shecheng GAO Yuanhua FENG Shancheng ZHAO Weiping LIU Changyuan YU Zhaohui LI Department of Electronic Engineering College of Information Science and Technology Jinan University Optical Research Department Huawei Technologies Co. Ltd. Department of Electronic and Information Engineering The Hong Kong Polytechnic University Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems Sun Yat-sen University Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)

High peak-to-average power ratio(PAPR) is a major drawback of discrete multi-tone(DMT) in peak-power-constraint(PPC) intensity-modulation/direct-detection(IM/DD) optical systems. Symmetric clipping operation is a frequently-used and practical method for mitigating the PAPR of the DMT ***, clipping noise is inevitably induced by the symmetric clipping operation, thereby deteriorating the system's performance. In this paper, we study the statistical characteristics of the clipping noise in *** on the statistical characteristics, clipping-noise-cancellation(CNC) algorithms are proposed to mitigate the clipping noise in the clipping DMT systems. Theoretically, the clipping noise can be completely removed using the low-density-parity-check-assisted CNC algorithm(LDPC-assisted CNC algorithm). To verify the superiority of the clipping DMT with the CNC algorithm, we conduct an experiment with a50 Gb/s DMT system using 10G-class commercial devices for the scenario of PPC passive optical *** receiver sensitivity of the clipping DMT system with the CNC algorithm can reach-24 d Bm at a 20%soft-decision forward-error-correction limit, which is 2.5 d B higher than that of the DMT system without clipping operation. The clipping operation and the CNC algorithm are added after the original digital signal processing, thereby demonstrating the potential to efectively overcome the drawback in DMT signals and other high-PAPR signals.

关键词： discrete multi-tone peak-to-average power ratio peak-power constraint clipping-noise cancellation intensity-modulation/direct-detection optical systems

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Distributed formation control of multiple aerial vehicles based on guidance route

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Chinese Journal of Aeronautics 2023年第3期36卷 368-381页

作者： Jinyong CHEN Rui ZHOU Guibin SUN Qingwei LI Ning ZHANG School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Science and Technology on Information Systems Engineering Laboratory Nanjing 210007China AVIC Xi’an Flight Automatic Control Research Institute Xi’an 710076China

Formation control of fixed-wing aerial vehicles is an important yet rarely addressed problem because of their complex dynamics and various motion constraints,such as nonholonomic and velocity *** guidance-route-based strategy has been demonstrated to be applicable to fixed-wing ***,it requires a global coordinator and there exists control lag,due to its own *** this reason,this paper presents a fully distributed guidance-route-based formation approach to address the aforementioned ***,a hop-count scheme is introduced to achieve distributed implementation,in which each aircraft chooses a neighbor with the minimum hop-count as a reference to generate its guidance route using only local ***,the model predictive control algorithm is employed to eliminate the control lag and achieve precise formation shape *** addition,the stall protection and collision avoidance are also ***,three numerical simulations demonstrate that our proposed approach can implement precise formation shape control of fixed-wing aircraft in a fully distributed manner.

关键词： Formation shape control Fixed-wing aircraft Guidance route Hop-count estimation Model predictive control

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Lattice plainification and band engineering lead to high thermoelectric cooling and power generation in n-type Bi2Te3 with mass production

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National science Review 2025年第2期12卷 276-285页

作者： Dongrui Liu Shulin Bai Yi Wen Jiayi Peng Shibo Liu Haonan Shi Yichen Li Tao Hong Huiqiang Liang Yongxin Qin Lizhong Su Xin Qian Dongyang Wang Xiang Gao Zhihai Ding Qian Cao Qing Tan Bingchao Qin Li-Dong Zhao School of Materials Science and Engineering Beihang University Center for Bioinspired Science and Technology Hangzhou International Innovation InstituteBeihang University Hebei Key Laboratory of Optic-Electronic Information and Materials College of Physics Science and Technology Hebei University School of Materials Science and Engineering Taiyuan University of Science and Technology Key Laboratory of Materials Physics of Ministry of Education School of Physics Zhengzhou University Center for High Pressure Science and Technology Advanced Research(HPSTAR) Huabei Cooling Device Co.LTD Tianmushan Laboratory

Thermoelectrics can mutually convert between thermal and electrical energy, ensuring its utilization in both power generation and solid-state cooling. Bi2Te3exhibits promising room-temperature performance,making it the sole commercially available thermoelectrics to date. Guided by the lattice plainification strategy, we introduce trace amounts of Cu into n-type Bi2（Te, Se）3（BTS） to occupy Bi vacancies, thereby simultaneously weakening defect scattering and modulating the electronic bands. Meanwhile, the interstitial Cu can bond with the BTS matrix to form extra electron transport pathways. The multiple occupations of Cu substantially boost carrier mobility and electrical performance. Consequently, the BTS + 0.2%Cu achieves a room-temperature ZT of ～1.3 with an average ZTaveof ～1.2 at 300–523 K. Moreover, the kilogram-scale ingot designed for mass production also exhibits high uniformity. Finally, we fabricate a full-scale device that achieves an excellent conversion efficiency of ～6.4% and a high cooling ΔTmaxof～70.1 K, both of which outperform commercial devices.

关键词： thermoelectric n-type BiTe lattice plainification carrier mobility thermoelectric device

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Overcoming bubble formation in polydimethylsiloxane-made PCR chips: mechanism and elimination with a high-pressure liquid seal

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Microsystems & Nanoengineering 2024年第5期10卷 209-219页

作者： Shiyuan Gao Tiegang Xu Lei Wu Xiaoyue Zhu Xuefeng Wang Xiaohong Jian Xinxin Li State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBejing 100049China School of Information Science and Technology ShanghaiTech UniversityShanghai 201210China Fujian Provincial Key Laboratory of Haixia Applied Plant Systems Biology Metabolomics CenterHaixia Institute of Science and TechnologySchool of Future TechnologyFujian Agriculture and Forestry UniversityFuzhou 350002China School of Biological Engineering Sichuan University of Science and EngineeringYibin 644000China

The thermal expansion of gas and the air permeability of polydimethylsiloxane(PDMS)were previously thought to be the main causes of bubbles and water loss during polymerase chain reaction(PCR),resulting in a very complex chip design and ***,by calculating and characterizing bubble formation,we discovered that water vapor is the main cause of *** PCR,heat increases the volume of the bubble by a factor of only~0.2 in the absence of water vapor but by a factor of~6.4 in the presence of water *** addition,the phenomenon of"respiration"due to the repeated evaporation and condensation of water vapor accelerates the expansion of bubbles and the loss of water.A water seal above 109 kPa can effectively prevent bubbles in a bare PDMS chip with a simple structure,which is significant for the wide application of PDMS chips.

关键词： bubble expansion elimination

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OFDM-structure based waveform designs for integrated sensing and communication

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science China(information sciences) 2025年第5期68卷 267-284页

作者： Jiaqi LIU Ping YANG Ke JIANG Jiarong ZHAO Wei XIANG Jianping WEI Ruixiang DUAN Saviour ZAMMIT Tony Q.S.QUEK National Key Laboratory of Wireless Communications University of Electronic Science and Technology of China School of Computing Engineering and Mathematical Sciences La Trobe University Meituan Academy of Robotics Department of Communications and Computer Engineering University of Malta Information Systems Technology and Design Pillar Singapore University of Technology and Design

The future sixth-generation(6G) paradigm aims to seamlessly integrate communication and environmental sensing capabilities into a single radio signal, promising improved efficiency and cost-effectiveness through simultaneous data communications and environmental perception. At the core of this evolution, orthogonal frequency division multiplexing(OFDM) and its advanced waveforms emerge as pivotal for integrated sensing and communications(ISAC). This study introduces a concise and unified ISAC waveform design framework based on orthogonal multicarriers. This framework supports versatile applications of OFDM and its derivative waveforms within a generalized ISAC system, marking a significant leap in integrating communication and sensing capabilities. A distinguishing feature of this framework is its adaptability,allowing users to intelligently select modulation strategies based on their specific environmental needs. This adaptability optimizes performance across diverse scenarios. Central to our innovations is the proposal of discrete Fourier transformspread OFDM with index modulation(DFT-S-OFDM-IM). This framework is paired with newly proposed signal processing methods for single-input single-output and multiple-input multiple-output(MIMO) systems. Extensive evaluations highlight DFT-S-OFDM-IM's superiority, including dramatically reduced peak-to-average power ratios(PAPRs), competitive communication performance, and exceptional sensing capabilities, striking an elegant balance between communication capacity and environmental sensing precision.

关键词： DFT-S-OFDM-IM index modulation integrated sensing and communication OFDM

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On-orbit attitude planning for Earth observation imaging with star-based geometric calibration

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science China(Technological sciences) 2025年第2期68卷 243-256页

作者： Di HUANG Zhifu WANG Jianya GONG Haoran JI Institute of Aerospace Science and Technology School of Remote Sensing and Information EngineeringWuhan UniversityWuhan 430072China State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingSchool of Remote Sensing and Information EngineeringWuhan UniversityWuhan 430072China National Key Laboratory of Air-based Information Perception and Fusion Luoyang 471009China Intelligent Game and Decision Laboratory Beijing 100071China

To improve the quality of remote sensing images,a novel on-orbit attitude planning method for Earth observation imaging with star-based geometric calibration is presented in this *** traditional imaging processes,the proposed method includes both pre-calibration and post-calibration stages to enhance the accuracy of satellite geometric positioning.A multiple-constraint attitude planning algorithm was developed to ensure star-based calibration,wherein the satellite camera and star sensors simultaneously capture the images of *** integration of cameras and multiple star sensors enables effective attitude *** the Earth imaging stage,a fast on-orbit attitude planning algorithm was developed to determine the satellite attitude and the optimal imaging times for ground *** with existing methods,the fast on-orbit attitude planning algorithm can significantly reduce computational time and resource consumption via initial value selection and *** demonstrate the effectiveness of the proposed attitude planning method,which was successfully applied to Wuhan 1 satellite.

关键词： attitude planning Earth observation imaging geometric calibration attitude constraints

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On-Policy and Off-Policy Value Iteration Algorithms for Stochastic Zero-Sum Dynamic Games

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Journal of systems science & Complexity 2025年第1期38卷 421-435页

作者： GUO Liangyuan WANG Bing-Chang ZHANG Ji-Feng School of Control Science and Engineering Shandong UniversityJinan 250063China School of Automation and Electrical Engineering Zhongyuan University of TechnologyZhengzhou 450007China Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China

This paper considers the value iteration algorithms of stochastic zero-sum linear quadratic games with unkown ***-policy and off-policy learning algorithms are developed to solve the stochastic zero-sum games,where the system dynamics is not *** analyzing the value function iterations,the convergence of the model-based algorithm is *** equivalence of several types of value iteration algorithms is *** effectiveness of model-free algorithms is demonstrated by a numerical example.

关键词： Approximate dynamic programming on-policy off-policy stochastic zero-sum games valueiteration

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