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An efficient quantum proactive incremental learning algorithm

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 49-57页

作者： Lingxiao Li Jing Li Yanqi Song Sujuan Qin Qiaoyan Wen Fei Gao State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications School of Cyberspace Security Beijing University of Posts and Telecommunications

In scenarios where a large amount of data needs to be learned, incremental learning can make full use of old knowledge, significantly reduce the computational cost of the overall learning process, and maintain high performance. In this paper, taking the MaxCut problem as our example, we introduce the idea of incremental learning into quantum computing, and propose a Quantum Proactive Incremental Learning algorithm(QPIL). Instead of a one-off training of quantum circuit, QPIL contains a multi-phase training on gradually-increased subgraphs of all vertices, proactively reducing large-scale problems to smaller ones to solve in steps, providing an efficient solution for MaxCut. Specifically, some vertices and corresponding edges are randomly selected for training to obtain optimized parameters of the quantum circuit at first. Then, in each incremental phase, the remaining vertices and corresponding edges are gradually added and the parameters obtained from the previous phase are reused in the parameter initialization of the current phase. We perform experiments on 120 different small-scale graphs, and it shows that QPIL performs superior to prevalent quantum and classical baselines in terms of approximation ratio(AR), time cost, anti-forgetting, and solving stability. In particular, QPIL's AR surpasses 20% of mainstream quantum baselines, and the time cost is less than 1/5 of them. The idea of QPIL is expected to inspire efficient and high-quality solutions in large-scale Max Cut and other combinatorial optimization problems.

关键词： variational quantum algorithm incremental learning multi-phase training MaxCut quantum computing

PS-CoT-Adapter: adapting plan-and-solve chain-of-thought for ScienceQA

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Science China(Information Sciences) 2025年第1期68卷 392-393页

作者： Qun LI Haixin SUN Fu XIAO Yiming WANG Xinping GAO Bir BHANU School of Computer Science Nanjing University of Posts and Telecommunications Purple Mountain Laboratories Department of Electrical and Computer Engineering University of California at Riverside

Large language models (LLMs) have recently shown remarkable performance in a variety of natural language processing (NLP) *** further explore LLMs'reasoning abilities in solving complex problems,recent research [1-3]has investigated chain-of-thought (CoT) reasoning in complex multimodal scenarios,such as science question answering (ScienceQA) tasks [4],by fine-tuning multimodal models through human-annotated CoT ***,collected CoT rationales often miss the necessary rea-soning steps and specific expertise.

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Actively tunable electromagnetically induced transparency in hybrid Dirac-VO2 metamaterials

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Optoelectronics Letters 2025年第1期21卷 13-20页

作者： DI Ke XIE Meng XIA Huarong CHENG Anyu LIU Yu DU Jiajia Department of Optoelectronic Engineering Chongqing University of Post and Telecommunications Chongqing Key Laboratory of Autonomous Navigation and Microsystem Chongqing University of Posts and Telecommunications Department of Automation Chongqing University of Post and Telecommunications

In this paper, we present a metamaterial structure of Dirac and vanadium dioxide（VO2） and investigate its optical properties using the finite-difference time-domain（FDTD） technique. Using the phase transition feature of VO2, the design can realize active tuning of the plasmon induced transparency（PIT） effect at terahertz frequency, thereby converting from a single PIT to a double-PIT. When VO2is in the insulating state, the structure is symmetric to obtain a single-band PIT effect. When VO2is in the metallic state, the structure turns asymmetric to realize a dual-band PIT effect. This design provides a reference direction for the design of actively tunable metamaterials. Additionally, it is discovered that the transparent window's resonant frequency and the Fermi level in this structure have a somewhat linear relationship. In addition, the structure achieves superior refractive index sensitivity in the terahertz band, surpassing 1 THz/RIU. Consequently, the design exhibits encouraging potential for application in refractive index sensors and optical switches.

关键词： Transparency

Future development research of 5G positioning in 3GPP standards

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The Journal of China Universities of posts and telecommunications 2025年

作者： Liu Wen Ren Hailong Deng Zhongliang School of Electronic Engineering， Beijing university of posts and telecommunications

Since the release of the first version of the 5th Generation Mobile Networks (5G) standard， Release-15 (Rel-15)， in June 2018， the 3rd Generation Partnership Project (3GPP) made significant efforts in the field of indoor and outdoor wireless positioning. Notably， Release-16 augmented support for enhanced mobile broadband (eMBB) and ultra-reliable low-latency communication (uRLLC)， particularly within complex indoor settings. To further meet the diverse application needs of positioning scenarios， the 3GPP standards for Release-17 and Release-18 propose new enhancement measures to continuously provide more accurate positioning services. In this paper， the scholarly discourse on 5G positioning was critically examined， providing a systematic review of the 5G positioning standards as delineated in 3GPP's Release-16 and Release-17， and was extended the discussion to the anticipated enhancements in 5G Release-18， along with their underlying motivations. Through these discussions， this article not only a comprehensive perspective on the current development of 5G positioning technology was provided but also was offered forward-looking analysis and predictions for the evolution of positioning technology in the upcoming 3GPP Release-19 phase. Additionally， it serves as a reference for researchers interested in understanding the development of positioning within the standard framework in the field of 5G indoor positioning， which holds significant meaning for promoting research and application of 5G positioning technology.

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A stretchable, ionic conductive, and adhesive patch electrode with ultra-low on-skin impedance for electrophysiological signal recording

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Science China(Information Sciences) 2025年

作者： Yang LI Yuzhe GU Sheng QIAN Yuncong PANG Aoxi YU Shuwen ZHENG Wenjie XIA Yuan LIAO Baoguang LIU Shujuan LIU Qiang ZHAO College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology) Nanjing University of Posts & Telecommunications (NJUPT) State Key Laboratory of Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications (NJUPT)

Flexible electrodes have significant potential in fields such as healthcare and neuroscience, as they enable comprehensive recording and analysis of human electrical signals, providing deeper insights into physiological conditions and the state of internal organs and tissues [1, 2]. However, commercial Ag/AgCl wet electrodes face issues such as dehydration,poor comfort, and insufficient mechanical strength, while other types of electrodes, like dry and semi-dry electrodes,also have their own limitations, including the higher contact impedance. In contrast, ionically conductive electrodes offer potential advantages such as transparency, stability, and low impedance, making them a promising alternative to existing electrically conductive electrodes [3]. Acrylic acid (AA)and 2-acrylamido-2-methylpropanesulfonic acid (AMPS) are commonly used in the synthesis of ionic gels, as they ionize in water to produce a large number of ions, helping to maintain moisture balance and reduce impedance caused by dehydration [4]. However, the presence of freely moving ions in the gel network can interfere with conductivity, highlighting the need to introduce new conductive networks to enhance performance [5].

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Secure beamforming and deployment design for rate-splitting multiple access-based UAV communications

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Science China(Information Sciences) 2025年第1期68卷 342-356页

作者： Bing WANG Xiaofeng TAO Shujun HAN Huici WU Kai YANG Zhu HAN National Engineering Research Center of Mobile Network Technologies Beijing University of Posts and Telecommunications Peng Cheng Laboratory Department of Electrical and Computer Engineering University of Houston

Rate-splitting multiple access(RSMA) has recently gained attention as a potential robust multiple access(MA)scheme for upcoming wireless networks. Given its ability to efficiently utilize wireless resources and design interference management strategies, it can be applied to unmanned aerial vehicle(UAV) networks to provide convenient services for large-scale access ground users. However, due to the line-of-sight(LoS) broadcast nature of UAV transmission, information is susceptible to eavesdropping in RSMA-based UAV networks. Moreover, the superposition of signals at the receiver in such networks becomes complicated. To cope with the challenge, we propose a two-user multi-input single-output(MISO) RSMA-based UAV secure transmission framework in downlink communication networks. In a passive eavesdropping scenario, our goal is to maximize the sum secrecy rate by optimizing the transmit beamforming and deployment location of the UAV-base station(UAV-BS),while considering quality-of-service(QoS) constraints, maximum transmit power, and flight space limitations. To address the non-convexity of the proposed problem, the optimization problem is first decoupled into two subproblems. Then, the successive convex approximation(SCA) method is employed to solve each subproblem using different propositions. In addition, an alternating optimization(AO)-based location RSMA(L-RSMA) beamforming algorithm is developed to implement joint optimization to obtain the suboptimal solution. Numerical results demonstrate that(1) the proposed L-RSMA scheme yields a28.97% higher sum secrecy rate than the baseline L-space division multiple access(SDMA) scheme;(2) the proposed L-RSMA scheme improves the security performance by 42.61% compared to the L-non-orthogonal multiple access(NOMA) scheme.

关键词： rate-splitting multiple access UAV communication precoding optimization deployment location physical layer security

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Distributed optimal consensus control for multiagent systems based on event-triggered and prioritized experience replay strategies

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Science China(Information Sciences) 2025年第1期68卷 306-321页

作者： Cuijuan ZHANG Lianghao JI Shasha YANG Xing GUO Huaqing LI Chongqing Key Laboratory of Image Cognition Chongqing University of Posts and Telecommunications Key Laboratory of Intelligent Perception and Computing of Anhui Province Anqing Normal University College of Electronic and Information Engineering Southwest University

This study uses event-triggered(ET) and reinforcement learning methods to investigate the optimal consensus control problem for cooperative-competitive multiagent systems. It proposes a novel distributed ET control strategy, which relies on a prioritized experience replay(PER) policy. This strategy not only conserves communication resources but also ensures acceptable system performance. To implement the proposed method, actor-critic(AC) dual-structured neural networks(NNs) are used to approximate the value function and control policy. In the AC NNs, the weight estimates for the NNs are updated at the moment of event triggering, resulting in a nonperiodic weight adjustment pattern. This approach decreases the computational cost in comparison with the traditional ET mechanism. The PER-based ET mechanism makes full use of valid historical data and effectively establishes a balance between system performance and communication resource ***, it does not require the following two conditions in most existing studies:(1) requirement of the system dynamics model to be known, and(2) persistent excitation. In addition, Zeno behavior is excluded from this study. Finally, a simulation is conducted to confirm the validity of the suggested approach.

关键词： multiagent systems event-triggered mechanism prioritized experience replay dual-structured neural networks optimal consensus control

Experimental demonstration of 220-GHz terahertz signals wireless transmission over 4.6 km

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Science China(Information Sciences) 2025年第1期68卷 386-388页

作者： Yi WEI Jianjun YU Mingxu WANG Xiongwei YANG Qiutong ZHANG Jingwen TAN Bing ZHANG Ying WU Yang HAN Peng TIAN Wen ZHOU Kaihui WANG Feng ZHAO State Key Laboratory of ASIC and System Key Laboratory for Information Science of Electromagnetic Waves (MoE)School of Information Science and Technology Fudan University School of Electronic Engineering Xi'an University of Posts and Telecommunications

The advancement of terahertz (THz) communication technology drives the evolution of wireless communication systems,offering novel pathways and technical means for the development of future 6G communication *** wireless communication systems are often constrained by bandwidth limitations of electronic devices in high frequency ***,THz communication technology leverages the characteristics of electromagnetic waves to transcend these limitations,enabling communication athigher frequencies and wider bandwidths.

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Design of a terahertz slotted waveguide array antenna based on photonic crystal

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Optoelectronics Letters 2025年

作者： PAN Wu YE Kuan ZHANG Zhen LI Renpu QIU Sen HUANG Lei College of Photoelectronic Engineering， Chongqing university of posts and telecommunications Chongqing Municipal Key Laboratory of Photoelectric Information Sensing and Transmission Technology， Chongqing university of posts and telecommunications Laboratory of Quantum Information Technology， Chongqing university of posts and telecommunications

In this paper， a terahertz slotted waveguide array antenna is designed based on photonic crystal， which can realize efficient radiation of terahertz waves. The electromagnetic wave is fed from the rectangular waveguide at the bottom of the antenna， coupled to photonic crystal waveguide through photonic crystal cavity， and radiated outward through slots at the top layer of antenna. The simulation results show that the antenna achieves a peak gain of 13.45dBi at 360 GHz， a half-power beamwidth of 10.9o， and a side lobe level of -13.9dB. The antenna based on photonic crystal has the advantages of low profile， low loss， and high radiation efficiency， which can be applied to terahertz wireless communication systems.

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