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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1342-1357页

作者： Sheng Qi Rui Wang Tao Zhang Xu Yang Ruiqing Sun Ling Wang College of Systems Engineering National University of Defense TechnologyChangsha 410073China Xiangjiang Laboratory Changsha 410205China College of Computer National University of Defense TechnologyChangsha 410073China Department of Automation Tsinghua UniversityBeijing 100084China IEEE

Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are *** a result,many algorithms use a two-layer encoding approach to optimize binary variable Mask and real variable Dec ***,existing optimizers often focus on locating non-zero variable posi-tions to optimize the binary variables ***,approxi-mating the sparse distribution of real Pareto optimal solutions does not necessarily mean that the objective function is *** data mining,it is common to mine frequent itemsets appear-ing together in a dataset to reveal the correlation between *** by this,we propose a novel two-layer encoding learning swarm optimizer based on frequent itemsets(TELSO)to address these *** mined the frequent terms of multiple particles with better target values to find mask combinations that can obtain better objective values for fast ***-mental results on five real-world problems and eight benchmark sets demonstrate that TELSO outperforms existing state-of-the-art sparse large-scale multi-objective evolutionary algorithms(SLMOEAs)in terms of performance and convergence speed.

关键词： Evolutionary algorithms learning swarm optimiza-tion sparse large-scale optimization sparse large-scale multi-objec-tive problems two-layer encoding.

Simulating a Chern Insulator with C = ±2 on Synthetic Floquet Lattice

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Chinese Physics Letters 2024年第9期41卷 4-11页

作者：雷凌霄王伟臣黄光耀胡顺曹希张鑫方邓明堂陈平形 Institute for Quantum Science and Technology College of ScienceNational University of Defense Technology Institute for Quantum Information & State Key Laboratory of High Performance Computing College of Computer Science and Technology National University of Defense Technology Greatwall Quantum Laboratory Hefei national Laboratory

The synthetic Floquet lattice, generated by multiple strong drives with mutually incommensurate frequencies,provides a powerful platform for quantum simulation of topological phenomena. In this study, we propose a 4-band tight-binding model of the Chern insulator with a Chern number C = ±2 by coupling two layers of the half Bernevig-Hughes-Zhang lattice and subsequently mapping it onto the Floquet lattice to simulate its topological properties.

关键词： Quantum computers

Self-Powered Absorptive Reconfigurable Intelligent Surfaces for Securing Satellite-Terrestrial Integrated Networks

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China communications 2024年第9期21卷 276-291页

作者： Lin Zhi Niu Hehao He Yuanzhi An Kang Zhong Xudong Chu Zheng Xiao Pei College of Electronic Engineering National University of Defense TechnologyHefei 230037China Sixty-Third research Institute National University of Defense TechnologyNanjing 210007China Institute of Systems Engineering Academy of Military ScienceBeijing 100141China Department of Electrical and Electronic Engineering University of Nottingham Ningbo ChinaNingbo 315100China Institute for communication Systems University of SurreyGuildford GU27XHU.K.

Satellite communications have attracted significant interests due to its advantages of large footprint and massive ***,the commonly used onboard beamforming is hard to achieve reliable security because of the highly correlated legitimate and wiretap downlink *** exploit the benefits of satellite-terrestrial integrated network(STIN)and a novel absorptive reconfigurable intelligent surface(RIS)for improving the security of satellite downlink communications(SDC)in the presence of eavesdroppers(Eves).This paper aims to maximize the achievable secrecy rate of the earth station(ES)while satisfying the signal reception constraints,harvested power threshold at the RIS,and total transmit power *** solve this nonconvex problem,we propose a penalty-function based dual decomposition scheme,which firstly transforms the original problem into a two-layer optimization ***,the outer layer and inner problems are solved by utilizing the successive convex approximation,Lagrange-dual and Rayleigh quotient methods to obtain the beamforming weight vectors and the reflective coefficient ***,simulation results verify the effectiveness of the proposed scheme for enhancing the SDC security.

关键词： absorptive RIS beamforming design secure communications STIN

Constructing the Impossible Differential of Type-II GFN with Boolean Function and Its Application to WARP

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Chinese Journal of Electronics 2024年第1期33卷 80-89页

作者： Jiali SHI Guoqiang LIU Chao LI College of Liberal Arts and Sciences National University of Defense Technology Hunan Engineering research Center of Commercial Cryptography Theory and Technology Innovation State Key Laboratory of Information Security Institute of Information Engineering

Type-Ⅱ generalized Feist el network(GFN) has attracted a lot of attention for its simplicity and high *** differential attack is one of the powerful cryptanalytic approaches for word-oriented block ciphers such as Feistel-like *** deduce the impossible differential of Type-Ⅱ GFN by analyzing the Boolean function in the middle *** main idea is to investigate the expression with the variable representing the plaintext(ciphertext) difference words for the internal state *** adopting the miss-in-the-middle approach,we can construct the impossible differential of Type-Ⅱ *** an illustration,we apply this approach to WARP,a lightweight 128-bit block cipher with a 128-bit key which was presented by Banik et *** SAC *** structure of WARP is a 32-branch Type-Ⅱ ***,we find two 21-round truncated impossible differentials and implement a 32-round key recovery attack on *** the 32-round key recovery attack on WARP,some observations are used to mount an effective *** the advantage of the early abort technique,the data,time,and memory complexities are 2125.69chosen plaintexts,2126.6832-round encryptions,and 2100-bit,*** the best of our knowledge,this is the best attack on WARP in the single-key scenario.

关键词： Ciphers Boolean functions Parallel processing Complexity theory

Optimum process conditions for preparation of Cu-en/AP composite microspheres by electrostatic spray method based on ANSYS(Fluent) simulation

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火炸药学报 2024年

作者： Lei Liu TianYuan Hu MingJun Song Wei Ji national Academy of defense Technology， Southwest University of Science and Technology 201 research Institute， Sixth research Institute of China Aerospace Science and Industry Corporation

This study employed ANSYS (Fluent) to set up an orthogonal experimental design for simulating the preparation of AP/Cu-en composite microspheres via the electrostatic spray method. Additionally， a controlled variable approach was used to simulate the influence of flow rate， solvent ratio， and solid mass on the experimental results. The purpose is to study the optimal process conditions for preparing Cu-en/AP composite microspheres through electrostatic spray and to reveal the effects of changes in droplet properties and flow rate during the electrostatic spray process on the experimental *** results indicate that under the following process conditions: a flow rate of 2.67e-3 kg/s， acetone to deionized water ratio of 1.5:1， and a solid mass of 200 mg， the theoretical diameter of the composite microspheres can reach the nanoscale. These microspheres exhibit high velocity within the electric field， there was no significant deviation in the motion trajectory. The particle diameter decreases with the increase of *** the process，This decreasing trend begins to moderate when the flow rate is 1e-3kg/s. When increasing the solvent ratio (higher acetone content)，at the begging，the particle diameter is reduced， followed by an increase. An increase in solid mass also leads to reduced in particle diameter. At a solid mass of approximately 220 mg， the particle diameter starts to increase linearly. It will be explained in detail in this paper.

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Reduced-complexity multiple parameters estimation via toeplitz matrix triple iteration reconstruction with bistatic MIMO radar

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Chinese Journal of Aeronautics 2024年第7期37卷 482-495页

作者： Chenghong ZHAN Guoping HU Junpeng SHI Fangzheng ZHAO Hao ZHOU Graduate College Air Force Engineering UniversityXi’an 710051China Air and Missile defense College Air Force Engineering UniversityXi’an 710051China College of Electronic Countermeasure National University of Defense TechnologyHefei 230037China Beijing Aeronautical Technology research Center Beijing 100076China

In this advanced exploration, we focus on multiple parameters estimation in bistatic Multiple-Input Multiple-Output(MIMO) radar systems, a crucial technique for target localization and imaging. Our research innovatively addresses the joint estimation of the Direction of Departure(DOD), Direction of Arrival(DOA), and Doppler frequency for incoherent targets. We propose a novel approach that significantly reduces computational complexity by utilizing the TemporalSpatial Nested Sampling Model(TSNSM). Our methodology begins with a multi-linear mapping mechanism to efficiently eliminate unnecessary virtual Degrees of Freedom(DOFs) and reorganize the remaining ones. We then employ the Toeplitz matrix triple iteration reconstruction method, surpassing the traditional Temporal-Spatial Smoothing Window(TSSW) approach, to mitigate the single snapshot effect and reduce computational demands. We further refine the highdimensional ESPRIT algorithm for joint estimation of DOD, DOA, and Doppler frequency, eliminating the need for additional parameter pairing. Moreover, we meticulously derive the Cramér-Rao Bound(CRB) for the TSNSM. This signal model allows for a second expansion of DOFs in time and space domains, achieving high precision in target angle and Doppler frequency estimation with low computational complexity. Our adaptable algorithm is validated through simulations and is suitable for sparse array MIMO radars with various structures, ensuring higher precision in parameter estimation with less complexity burden.

关键词： MIMO Radar Multipleparameters estimation Temporal-spatial Nested Sampling Multi-linear mapping mechanism Toeplitz matrix triple iteration reconstruction Reduce computational complexity

Tunable quantum dots in monolithic Fabry-Perot microcavities for high-performance single-photon sources

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Light(Science & Applications) 2024年第2期13卷 325-332页

作者： Jiawei Yang Yan Chen Zhixuan Rao Ziyang Zheng Changkun Song Yujie Chen Kaili Xiong Pingxing Chen Chaofan Zhang Wei Wu Ying Yu Siyuan Yu State Key Laboratory of Optoelectronic Materials and Technologies School of Electronics and Information TechnologySun Yat-Sen UniversityGuangzhou 510006China Institute for Quantum Science and Technology College of ScienceNational University of Defense TechnologyChangsha 410073China College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China Hunan Key Laboratory of Quantum Information Mechanism and Technology National University of Defense TechnologyChangsha 410073 HunanChina Hefei national Laboratory Hefei 230088China

Cavity-enhanced single quantum dots(QDs)are the main approach towards ultra-high-performance solid-state quantum light sources for scalable photonic quantum ***,harnessing the Purcell effect requires precise spectral and spatial alignment of the QDs’emission with the cavity mode,which is challenging for most *** we have successfully integrated miniaturized Fabry-Perot microcavities with a piezoelectric actuator,and demonstrated a bright single-photon source derived from a deterministically coupled QD within this *** the cavity-membrane structures,we have achieved large spectral tunability via strain *** resonance,a high Purcell factor of~9 is *** source delivers single photons with simultaneous high extraction efficiency of 0.58,high purity of 0.956(2)and high indistinguishability of 0.922(4).Together with its compact footprint,our scheme facilitates the scalable integration of indistinguishable quantum light sources on-chip,therefore removing a major barrier to the development of solid-state quantum information platforms based on QDs.

关键词： quantum removing purity

Gas film/regenerative composite cooling characteristics of the liquid oxygen/liquid methane (LOX/LCH4) rocket engine

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第8期25卷 631-649页

作者： Xinlin LIU Jun SUN Zhuohang JIANG Qinglian LI Peng CHENG Jie SONG Science and Technology on Scramjet Laboratory College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

The thermal protection of rocket engines is a crucial aspect of rocket engine *** this paper,the gas film/regenerative composite cooling of the liquid oxygen/liquid methane(LOX/LCH4)rocket engine thrust chamber was investigated.A gas film/regenerative composite cooling model was developed based on the Grisson gas film cooling efficiency formula and the one-dimensional regenerative cooling *** accuracy of the model was validated through experiments conducted on a 6 kg/s level gas film/regenerative composite cooling thrust ***,key parameters related to heat transfer performance were *** results demonstrate that the model is sufficiently accurate to be used as a preliminary design *** temperature rise error of the coolant,when compared with the experimental results,was found to be less than 10%.Although the pressure drop error is relatively large,the calculated results still provide valuable guidance for heat transfer *** addition,the performance of composite cooling is observed to be superior to regenerative *** the gas film flow rate results in higher cooling efficiency and a lower gas-side wall ***,the position at which the gas film is introduced greatly impacts the cooling *** optimal introduction position for the gas film is determined when the film is introduced from a single row of *** optimal introduction position results in a more uniform wall temperature distribution and reduces the peak ***,it is observed that a double row of holes,when compared to a single row of holes,enhances the cooling effect in the superposition area of the gas film and further lowers the gas-side wall *** results provide a basis for the design of gas film/regenerative composite cooling systems.

关键词： Liquid oxygen/liquid methane(LOX/LCH4)rocket engine Gas film cooling Regenerative cooling Heat transfer characteristics

Joint UAV trajectory and communication design with heterogeneous multi-agent reinforcement learning

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Science China(Information Sciences) 2024年第3期67卷 225-245页

作者： Xuanhan ZHOU Jun XIONG Haitao ZHAO Xiaoran LIU Baoquan REN Xiaochen ZHANG Jibo WEI Hao YIN College of Electronic Science and Technology National University of Defense Technology Systems Engineering Institute Academy of Military Sciences PLA

Unmanned aerial vehicles(UAVs) are recognized as effective means for delivering emergency communication services when terrestrial infrastructures are unavailable. This paper investigates a multiUAV-assisted communication system, where we jointly optimize UAVs’ trajectories, user association, and ground users(GUs)’ transmit power to maximize a defined fairness-weighted throughput metric. Owing to the dynamic nature of UAVs, this problem has to be solved in real time. However, the problem’s non-convex and combinatorial attributes pose challenges for conventional optimization-based algorithms, particularly in scenarios without central controllers. To address this issue, we propose a multi-agent deep reinforcement learning(MADRL) approach to provide distributed and online solutions. In contrast to previous MADRLbased methods considering only UAV agents, we model UAVs and GUs as heterogeneous agents sharing a common objective. Specifically, UAVs are tasked with optimizing their trajectories, while GUs are responsible for selecting a UAV for association and determining a transmit power level. To learn policies for these heterogeneous agents, we design a heterogeneous coordinated QMIX(HC-QMIX) algorithm to train local Q-networks in a centralized manner. With these well-trained local Q-networks, UAVs and GUs can make individual decisions based on their local observations. Extensive simulation results demonstrate that the proposed algorithm outperforms state-of-the-art benchmarks in terms of total throughput and system fairness.

关键词： unmanned aerial vehicle (UAV) trajectory design resource allocation multi-agent deep reinforcement learning (MADRL) heterogeneous agents

Track correlation algorithm based on CNN-LSTM for swarm targets

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Journal of Systems Engineering and Electronics 2024年第2期35卷 417-429页

作者： CHEN Jinyang WANG Xuhua CHEN Xian research Institute for national defense Engineering Academy of Military SciencesLuoyang 471023China Information Engineering University Zhengzhou 450001China School of Computer Science and Technology Xidian UniversityXi’an 710071China

The rapid development of unmanned aerial vehicle(UAV) swarm, a new type of aerial threat target, has brought great pressure to the air defense early warning system. At present, most of the track correlation algorithms only use part of the target location, speed, and other information for *** this paper, the artificial neural network method is used to establish the corresponding intelligent track correlation model and method according to the characteristics of swarm ***, a route correlation method based on convolutional neural networks (CNN) and long short-term memory (LSTM)Neural network is designed. In this model, the CNN is used to extract the formation characteristics of UAV swarm and the spatial position characteristics of single UAV track in the formation,while the LSTM is used to extract the time characteristics of UAV swarm. Experimental results show that compared with the traditional algorithms, the algorithm based on CNN-LSTM neural network can make full use of multiple feature information of the target, and has better robustness and accuracy for swarm targets.

关键词： track correlation correlation accuracy rate swarm target convolutional neural network(CNN) long short-term memory(LSTM)neural network