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Improve Chinese Aspect Sentiment Quadruplet Prediction via Instruction Learning Based on Large Generate Models

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Computers, Materials & Continua 2024年第3期78卷 3391-3412页

作者： Zhaoliang Wu Yuewei Wu Xiaoli Feng Jiajun Zou Fulian Yin college of information and communication Engineering Communication University of ChinaBeijing100024China The State Key Laboratory of Media Convergence and communication Communication University of ChinaBeijing100024China Department of Electronic Engineering Tsinghua UniversityBeijing100084China

Aspect-Based Sentiment Analysis(ABSA)is a fundamental area of research in Natural Language Processing(NLP).Within ABSA,Aspect Sentiment Quad Prediction(ASQP)aims to accurately identify sentiment quadruplets in target sentences,including aspect terms,aspect categories,corresponding opinion terms,and sentiment ***,most existing research has focused on English ***,while ASQP has seen significant progress in English,the Chinese ASQP task has remained relatively *** inspiration from methods applied to English ASQP,we propose Chinese generation templates and employ prompt-based instruction learning to enhance the model’s understanding of the task,ultimately improving ASQP performance in the Chinese ***,under the same pre-training model configuration,our approach achieved a 5.79%improvement in the F1 score compared to the previously leading ***,when utilizing a larger model with reduced training parameters,the F1 score demonstrated an 8.14%***,we suggest a novel evaluation metric based on the characteristics of generative models,better-reflecting model *** results validate the effectiveness of our approach.

关键词： ABSA ASQP LLMs sentiment analysis Chinese comments

Localization for mixed near-field and far-field sources under impulsive noise

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Journal of Systems Engineering and Electronics 2024年第2期35卷 302-315页

作者： GAO Hongyuan ZHANG Yuze DU Ya’nan CHENG Jianhua CHEN Menghan college of information and communication Engineering Harbin Engineering UniversityHarbin 150001China college of Intelligent Systems Science and Engineering Harbin Engineering UniversityHarbin 150001China

In order to solve the problem that the performance of traditional localization methods for mixed near-field sources(NFSs)and far-field sources(FFSs)degrades under impulsive noise,a robust and novel localization method is *** eliminating the impacts of impulsive noise by the weighted out-lier filter,the direction of arrivals(DOAs)of FFSs can be estimated by multiple signal classification(MUSIC)spectral peaks *** on the DOAs information of FFSs,the separation of mixed sources can be ***,the estimation of localizing parameters of NFSs can avoid two-dimension spectral peaks search by decomposing steering *** Cramer-Rao bounds(CRB)for the unbiased estimations of DOA and range under impulsive noise have been *** experiments verify that the proposed method has advantages in probability of successful estimation(PSE)and root mean square error(RMSE)compared with existing localization *** can be concluded that the proposed method is effective and reliable in the environment with low generalized signal to noise ratio(GSNR),few snapshots,and strong impulse.

关键词： source localization far-field source(NFS) near-field source(FFS) impulsive noise Cramer-Rao bound(CRB)

Ballistic target recognition based on multiple data representations and deep-learning algorithms

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Chinese Journal of Aeronautics 2024年第6期37卷 167-181页

作者： Lixun HAN Cunqian FENG Xiaowei HU Sisan HE Xuguang XU Air and Missile Defense college Air Force Engineering UniversityXi’an 710051China college of information and communication National University of Defense TechnologyWuhan 430010China

Target recognition is a significant part of a Ballistic Missile Defense System(BMDS).However,most existing ballistic target recognition methods overlook the impact of data representation on recognition *** paper focuses on systematically investigating the influences of three novel data representations in the Range-Doppler(RD)***,the Radar Cross Section(RCS)and micro-Doppler(m-D)characteristics of a cone-shaped ballistic target are ***,three different data representations are proposed:RD data,RD sequence tensor data,and RD trajectory *** accommodate various data inputs,deep-learning models are designed,including a two-Dimensional Residual Dense Network(2D RDN),a three-Dimensional Residual Dense Network-Gated Recurrent Unit(3D RDN-GRU),and a Dynamic Trajectory Recognition Network(DTRN).Finally,an Electromagnetic(EM)computation dataset is collected to verify the performances of the networks.A broad range of experimental results demonstrates the effectiveness of the proposed ***,several key parameters of the proposed networks and datasets are extensively studied in this research.

关键词： Ballistic target Micro-Doppler Deep learning Range-Doppler Radar target recognition

Modulated symbol-based one-time pad secure transmission scheme using physical layer keys

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Science China(information Sciences) 2024年第1期67卷 221-239页

作者： Xiaoyan HU Zheng WAN Kaizhi HUANG Liang JIN Mengyao YAN Yajun CHEN Jinmei YANG information Engineering University Purple Mountain Laboratories for Network and communication Security

This paper proposes a novel modulated symbols-based one-time pad(SOTP) secure transmission scheme using physical layer *** classical physical layer key generation and exclusive OR(XOR)encryption in the discrete binary space,we design a framework for modulated symbols-based one-time pad(OTP) encryption,where the cryptographic primitive and mathematical model of SOTP is given to build a practical cryptographic *** with existing physical layer encryption(PLE) schemes,we provide rigorous proof that the framework can meet perfect secrecy and correctness *** addition,we provide a specific scheme of physical layer OTP secure transmission for quadrature amplitude modulation(QAM) and phase-shift keying(PSK) symbols based on physical layer *** scheme realizes the unification of bit encryption and symbol encryption,which can adaptively select the quantization level according to the signal-to-noise ratio(SNR) to minimize the symbol error rate(SER).Further,we analyze the performance quantitatively and derive the closed-form expressions of SER,which indicates that the proposed scheme has a lower ***,simulation results verify that the proposed symbol-wise OTP secure transmission scheme can achieve perfect secrecy and high reliability.

关键词： physical layer security one-time pad wireless channel physical layer encryption perfect secrecy

Beamforming design for covert broadcast communication with hidden adversary

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Science China(information Sciences) 2024年第6期67卷 384-398页

作者： Weiyu CHEN Haiyang DING Shilian WANG Junshan LUO Fengkui GONG college of Electronic Science and Technology National University of Defense Technology college of information and communication National University of Defense Technology State Key Laboratory of Integrated Service Networks Xidian University

This paper explores covert broadcast communication in a challenging situation in which the transmitter, Alice, faces uncertainty regarding the position of the passive adversary, Willie. In this situation,controlling the signal exposure becomes difficult. Specifically, this paper focuses on the cases where Alice can delimit the suspicious areas where Willie may be located. The suspicious areas can have arbitrary number and shapes. Under the Rician fading model, the analytical expression of Willie's detection performance is derived. Then, the transmit power, the beamforming direction, and the number of channel uses are jointly designed to minimize the optimal Willie's detection performance among all the possible positions of Willie, on the premise of satisfying receivers' quality-of-service requirements. To tackle the formulated knotty problem with an infinite number of irregular and discontinuous Willie's possible positions, the continuous nature of the antenna pattern is exploited to convert the original problem into the one with a finite number of possible positions, by sampling the suspicious areas. Then, different algorithms are developed to address the resultant non-convex optimization problem for single-antenna Willie and multi-antenna Willie, respectively. Numerical results demonstrate significant performance gains of the proposed scheme over the widely-adopted maximum ratio transmission scheme, which indicates that simply adjusting the main lobe towards the receiver is indeed far away from optimum and shows the importance of leveraging Alice's limited knowledge of Willie's position.

关键词： low-probability-of-detection communication multiple antennas covertness performance uncertain position parameters optimization

Generative Multi-Modal Mutual Enhancement Video Semantic communications

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2985-3009页

作者： Yuanle Chen Haobo Wang Chunyu Liu Linyi Wang Jiaxin Liu Wei Wu The college of communication and information Engineering Nanjing University of Posts and TelecommunicationsNanjing210023China The college of Science Nanjing University of Posts and TelecommunicationsNanjing210023China

Recently,there have been significant advancements in the study of semantic communication in single-modal ***,the ability to process information in multi-modal environments remains *** by the research and applications of natural language processing across different modalities,our goal is to accurately extract frame-level semantic information from videos and ultimately transmit high-quality ***,we propose a deep learning-basedMulti-ModalMutual Enhancement Video Semantic communication system,called *** upon a VectorQuantized Generative AdversarialNetwork(VQGAN),our systemaims to leverage mutual enhancement among different modalities by using text as the main carrier of *** it,the semantic information can be extracted fromkey-frame images and audio of the video and performdifferential value to ensure that the extracted text conveys accurate semantic information with fewer bits,thus improving the capacity of the ***,a multi-frame semantic detection module is designed to facilitate semantic transitions during video *** results demonstrate that our proposed model maintains high robustness in complex noise environments,particularly in low signal-to-noise ratio conditions,significantly improving the accuracy and speed of semantic transmission in video communication by approximately 50 percent.

关键词： Generative adversarial networks multi-modal mutual enhancement video semantic transmission deep learning

Masked Autoencoders as Single Object Tracking Learners

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Computers, Materials & Continua 2024年第7期80卷 1105-1122页

作者： Chunjuan Bo XinChen Junxing Zhang School of information and communication Engineering Dalian Minzu UniversityDalian116600China School of information and communication Engineering Dalian University of TechnologyDalian116024China

Significant advancements have beenwitnessed in visual tracking applications leveragingViT in recent years,mainly due to the formidablemodeling capabilities of Vision Transformer(ViT).However,the strong performance of such trackers heavily relies on ViT models pretrained for long periods,limitingmore flexible model designs for tracking *** address this issue,we propose an efficient unsupervised ViT pretraining method for the tracking task based on masked autoencoders,called *** pretraining,we employ two shared-parameter ViTs,serving as the appearance encoder and motion encoder,*** appearance encoder encodes randomly masked image data,while the motion encoder encodes randomly masked pairs of video ***,an appearance decoder and a motion decoder separately reconstruct the original image data and video frame data at the pixel *** this way,ViT learns to understand both the appearance of images and the motion between video frames *** results demonstrate that ViT-Base and ViT-Large models,pretrained with TrackMAE and combined with a simple tracking head,achieve state-of-the-art(SOTA)performance without additional ***,compared to the currently popular MAE pretraining methods,TrackMAE consumes only 1/5 of the training time,which will facilitate the customization of diverse models for *** instance,we additionally customize a lightweight ViT-XS,which achieves SOTA efficient tracking performance.

关键词： Visual object tracking vision transformer masked autoencoder visual representation learning

Real-time UWOC miniaturized system based on FPGA and LED arrays and its application in MIMO

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Chinese Optics Letters 2024年第2期22卷 70-75页

作者：黄安殷洪玺梁彦军王建英沈众卫 School of information and communication Engineering Dalian University of TechnologyDalian 116024China

In order to alleviate the impact of turbulence on the performance of underwater wireless optical communication(UWOC)in real time,and achieve high-speed real-time transmission and low cost and miniaturization of equipment,a 2×2 real-time multiple-input and multiple-output(MIMO)high-speed miniaturized UWOC system based on a field-programmable gate array(FPGA)and a high-power light-emitting diode(LED)array is designed in this *** terms of multiplexing gain,the imaging MIMO spatial multiplexing and high-order modulation for the first time are combined and the real-time high-speed transmission of PAM-4 signal based on the LED array light source in 12 m underwater channel at 100 Mbps rate is implemented,which effectively improves the throughput of the UWOC system with a high-power commercial LED light *** light of diversity gain,the system employs the diversity of repeated coding scheme to receive two identical non-return-to-zero on-off keying(NRZ-OOK)signals,which can compensate the fading or flickering sublinks in real time under the bubble-like simulated turbulence condition,and has high *** our knowledge,this is the first instance of a high rate and long-distance implementation of a turbulence-resistant real-time MIMO miniaturized UWOC system based on FPGA and high-power LED *** spatial diversity or spatial multiplexing capabilities,its low cost,integrity,and high robustness provide the system with important practical prospects.

关键词： underwater wireless optical communication MIMO spatial diversity spatial multiplexing

The dawn−dusk asymmetry in mesosphere and lower thermosphere temperature disturbances during geomagnetic storms at high latitude

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Earth and Planetary Physics 2024年第2期8卷 356-367页

作者： GuanChun Wei JianYong Lu Fen Tang JingYuan Li Meng Sun Institute of Space Weather School of Atmospheric PhysicsNanjing University of Information Science&TechnologyNanjing 210044China college of information and communication National University of Defense TechnologyWuhan 430019China

Utilizing observations by the Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)instrument,we quantitatively assessed the dawn-dusk asymmetry in temperature disturbances within the high-latitude mesosphere and lower thermosphere(MLT)during the main phase of geomagnetic storms in this *** analysis of five geomagnetic superstorm events indicated that during the main phase,negative temperature disturbances were more prevalent on the dawn side than on the dusk side in the high-latitude MLT *** of a statistical analysis of 54 geomagnetic storm events also revealed a notable disparity in temperature disturbances between the dawn and dusk *** high latitudes,38.2%of the observational points on the dawn side exhibited negative temperature disturbances(less than−5 K),whereas on the dusk side,this percentage was only 29.5%.In contrast,at mid-latitudes,these proportions were 34.1%and 36.5%,respectively,showing no significant *** also conducted a statistical analysis of temperature disturbances at different altitudes,which revealed an increase in the proportion of warming disturbances with ***,the proportion of cooling disturbances initially rose with altitude,reaching a peak around 105 km,and subsequently *** temperature disturbance differences could be explained by the day-night asymmetry in vertical wind disturbances during storm conditions.

关键词： dawn dusk asymmetry SABER(Sounding of the Atmosphere using Broadband Emission Radiometry) geomagnetic storms mesosphere and lower thermosphere