最新刊期
卷 49 ， 期 9 ， 2021
- 摘要：Aiming at the problems of high discretization of aircraft’s backscattering points, complex background interference of surroundings in Synthetic Aperture Radar (SAR) images and weak representation of shallow semantic features of aircraft by existing algorithms, an Attention Feature Fusion Network (AFFN) was proposed for aircraft detection in SAR images. By introducing Bottleneck Attention Module (BAM), this article constructed an attention feature fusion strategy consisting of Attention Bidirectional Feature Fusion Module (ABFFM) and Attention Transfer Connection Block (ATCB) in AFFN, and rationally optimized the network structure so as to strengthen the abilities of extracting and discriminating shallow semantic features of aircraft. Based on a self-built Gaofen-3 and TerraSAR-X mixed aircraft dataset, AFFN was compared with several CNN-based general object detection methods and methods designed for specific objects in SAR images. The experimental results illustrated the accuracy and effectiveness of our method for aircraft detection in SAR images关键词：attention feature fusion network (AFFN);feature fusion;rapid aircraft detection;synthetic aperture radar (SAR) images;convolutional neural network (CNN)4|16|7更新时间：2025-12-08
- 摘要：Due to the dynamic change of multi-agent environment, and the decision of single agent will affect other agents, it is difficult for the deep reinforcement learning algorithm of single agent to maintain stability in multi-agent environment. In order to adapt to multi-agent environment, this paper uses centralized training and decentralized execution framework (CTDE) to improve single agent deep reinforcement learning algorithm soft actor-critic (SAC). By introducing agent communication mechanism, in multi-agent soft actor-critic (MASAC), agents share observation information and historical experience, which effectively reduces the impact of environmental instability on the algorithm. Finally, in the task of cooperation and cooperation and competition, the performance of MASAC algorithm is analyzed experimentally. The results show that MASAC has better stability than SAC in multi-agent environment.关键词：multi-agent environments;centralized training;decentralized execution;multi-agent deep reinforcement learning11|18|5更新时间：2025-12-08
- 摘要：Keyword extraction is a key basic problem in the field of natural language processing. The keyphrase extraction algorithms(PhraseVecRank) is proposed based on phrase embedding. Firstly, a phrase vector construction model based on LSTM（Long Short-Term Memory） and CNN（Convolutional Neural Network） is designed to solve the semantic representation of complex phrases. Then, PhraseVecRank uses phrase embedding to calculate theme weight for each candidate phrase, and uses semantic similarity between candidate phrase embedding and co-occurrence information to calculate edge weight together, which can improve the extraction effect of keyphrases through topic weighted ranking. The experimental results verify that PhraseVecRank can effectively extract keyphrases covering the topic information of text, and the phrase embedding models we proposed can better represent the semantic information of phrases.关键词：phrase embedding;auto-encoder;theme-weighted;keyphrases extraction3|17|1更新时间：2025-12-08
- 摘要：As for the measurement requirements of the pulse electric field with high intensity, wide frequency band and short duration, an all-dielectric electric field sensor based on photonic crystal with electro-optic polymer defect was proposed in this paper. The electro-optic polymer in the form of a defect layer was inserted in the periodic one-dimensional photonic crystal structure. The variations of refractive index of electro-optic polymer under the externally applied electric fields may induce the changes of the resonance wavelength of the defect mode. Accordingly, the applied electric field may be measured by monitoring the shift of the resonant wavelength. It is theoretically shown that the minimal detectable electric field of 30V/m can be achieved and the maximum detectable field could reach up to the order of MV/m.关键词：electromagnetic pulse measurement;photonic crystal;optical sensor3|14|1更新时间：2025-12-08
- 摘要：This paper presents a method by jointly designing the transmitted waveform and mismatched filter to suppress the pulse compression sidelobe level, thereby improving the detection and imaging performance of weak target. A waveform and mismatched filter joint design algorithm is proposed based on block-coordinate-descent optimization framework. Simulation results show that the proposed method improves the pulse compression sidelobe performance with slight loss in the processing gain, and outperforms the conventional joint design method in terms of running time. Besides, the design scheme is extended to orthogonal waveform set and mismatched filter bank design, and a joint design method is proposed based on parallel optimization. The designed waveform set and mismatch filters show good orthogonality performance.关键词：waveform design;mismatched filter;orthogonal waveform;integrated sidelobe levels;loss of processing gain;block coordinate descent method4|20|5更新时间：2025-12-08
- 摘要：This paper proposed an enhanced artificial bee colony algorithm (EABC) to minimize the maximum completion time of the semiconductor final test scheduling problem (SFTSP). EABC used hybrid heuristic methods to initialize the population, and used forward interpolation decoding strategies to improve the quality of the initial solution. A variety of exploration strategies based on the problem features and a Bayesian network‑based probability model were designed to conduct a depth and width search of the problem solution space. In addition, a population update mechanism based on the restart strategy was proposed to strengthen the algorithm's ability to jump out of the local optimum. In the experimental part, multiple comparison algorithms were constructed to verify the effectiveness of the EABC’s key components. Simulation results based on some instances and comparisons with NFOA(Novel Fruit fly Optimization Algorithm)、KMEA(Knowledge‑based Multi‑agent Evolutionary Algorithm) and CCIWO(Cooperative Co‑evolutionary Invasive Weed Optimization) demonstrated the effectiveness and robustness of the proposed algorithm.关键词：semiconductor final test;artificial bee colony algorithm;heuristic rules;Bayesian network;multi‑strategy integration;probability model;permutation‑based model2|24|2更新时间：2025-12-08
- 摘要：A Laplacian graph clustering algorithm based on word frequency processing is presented, to solve the problems of high feature dimension and sparse feature in short text. First, the term frequency-inverse document frequency (TF-IDF) method is used to map the short text dataset to the text vector space, to obtain the word frequency weight matrix. Secondly, the dimension of the word frequency weight matrix is reduced by using the graph clustering property of Laplacian matrix. Afterwards, according to the feature that the eigenvalues of Laplace matrix can represent the degree of text similarity, the eigenvectors corresponding to the first K eigenvalues are selected as the initial clustering center, thus reducing the number of iterations in the clustering process. We conduct extensive experiments on SSC, 20 News Group and Microblog PCU datasets. The results show that the Laplacian graph clustering algorithm not only has better clustering results and faster convergence speed compared with the traditional clustering algorithm, but also it is less affected by noises and has good robustness.关键词：laplacian graph;term frequency-inverse document frequency;short-text clustering;vector space model;data dimensionality reduction;feature weight5|13|1更新时间：2025-12-08
- 摘要：To solve the problems of local optimization and slow convergence in the process of optimization and iteration, the paper proposed an improved optimization algorithm for a salp swarm, i.e, step‑by‑step tent chaos simulated annealing salp swarm algorithm (STSA‑SSA). Firstly, an initial population of Tent chaotic map was introduced to enhance the algorithm convergence at the early stage of iteration, and a step adjustment strategy of inertia weights was employed to improve the global and local exploring ability of the STSA‑SSA. Then, the ability of escaping local optimal solutions of the STSA‑SSA at the later stage of iterations was increased by a simulated annealing policy. Finally, the performance of the STSA‑SSA was tested in the processes of optimizing the parameters of benchmark functions and a fuzzy controller a magnetic navigation automated guided vehicle (AGV). The results show that for the single peak and multi peak test functions, the STSA‑SSA has faster convergence speed and stronger global optimization ability. Compared with SSA, the fuzzy controller of the magnetic navigation AGV designed by STSA‑SSA is more optimized. Therefore, the STSA‑SSA has a potential engineering application value in controller designs.关键词：salp swarm algorithm;tent chaotic mapping;step weight;simulated annealing;system identification;AGV2|17|12更新时间：2025-12-08
- 摘要：By using the multi-path of wireless channels, time reversal (TR) transmission technology can focus the signal energy in a desired spatial and temporal point, so it has natural anti-eavesdropping capability. In this paper, a pre-equalizer shared by all antennas is added in front of the conventional pre-filters at the transmitter for a TR multiple-input single-output system. The optimization of the pre-equalizer is carried out for the maximization of secrecy rate. Compared with the joint optimization for the all pre-filters, the complexity of optimization for the pre-equalizer is significantly lower. The simulation results show that the security rate of the pre-equalized TR system optimized for secure transmission is about two times higher than that of the conventional TR transmission system at high transmission power with four transmitting antennas and one up sampling factor. And the more the number of antennas, the larger the up sampling factor, the more obvious the performance advantage.关键词：physical layer security;time reversal;pre-equalization;mingle-input single-output3|17|1更新时间：2025-12-08
- 摘要：The original CycleGAN show poor quality and time consuming in optical image to underwater small target synthetic aperture sonar image translation task. To address those problems, a novel convolution building block, SDK (Selective Dilated Kernel), is proposed. By stacking SDK blocks, a generator SDKNet is created. At the same time, Multiscale Cycle Consistent Loss Function (MS-CCLF) is proposed, which add the Multiscale Structural Similarity Index (MS-SSIM) between input images and reconstructed images. On our image translation dataset (OPT-SAS), the classification accuracy of our SM-CycleGAN is 4.64% higher than that of original CycleGAN. The generator parameters of SM-CycleGAN is 4.13MB lower than that of CycleGAN, and the time consuming of SM-CycleGAN is 0.143s less than that of CycleGAN. The experimental results show that SM -CycleGAN is more suitable for the translation task of optical image to small underwater target synthetic aperture sonar image.关键词：optical image-to-synthetic aperture sonar image translation;generative adversarial networks;cycle generative adversarial networks;selective dilated kernel networks;multiscale structural similarity index5|19|7更新时间：2025-12-08
- 摘要：This work proposes a multi-source mating selection based multi-objective evolutionary algorithm（MMSEA）. In MMSEA, the spectral clustering algorithm is used to exploit the property of the multi-objective optimization problems. Based on the obtained population structure information, a multi-source mating selection strategy is designed to guide the algorithm search. The convergence of the algorithm is accelerated and the diversity of the population is maintained by setting multiple mating selections for each individual and using similar-based reproduction. The experimental results show that the proposed reproduction operator can effectively improve the performance of the algorithm. MMSEA is experimentally compared with variety of mainstream multi-objective evolutionary algorithms, and parameter sensitivity is also performed. In these experiments, MMSEA demonstrates strong competitiveness over the other approaches in solving typical multi-objective optimization problems with complex characteristics.关键词：clustering learning;evolutionary algorithm;mating selection;multi-objective optimization2|17|1更新时间：2025-12-08
- 摘要：Aiming at the location of electric dipole sources in parallel layered seas, a method of using three electric field intensity sensors to simultaneously determine the field source position, electric dipole moment, and interface orientation is proposed. First, the matrix expressions of electric field strength generated by electric dipole sources in three layers of parallel and layered seas in seawater were derived by using the mirror method and boundary conditions. The field strength transfer matrix was introduced, and the electric dipoles were eliminated by the inversion of the transfer matrix. The parameters of the dipole moments of the sub-sources are used to obtain a set of nonlinear equations in which the position of the electric dipole source and the orientation of the interface are unknown. The 9 unknown parameters to be determined are reduced to 6 quantities to be fitted, and the optimal solution of the electric dipole source position and interface orientation is obtained through the fitting method. Finally, the validity of the proposed method is verified by simulation examples. The results show that the localization method can accurately determine the position of the field source and the orientation of the interface under certain conditions. The method can also be applied to torpedo guidance process after proper improvement.关键词：parallel layered seas;electric dipole;locating;method of images;transfer matrix5|12|0更新时间：2025-12-08
- 摘要：In order to realize the effective extraction of determined frequency signal under the strong noise environment，we propose a weak signal extraction method based on null space pursuit(NSP) and determined frequency signal constraint. The proposed approach inherits the excellent properties of NSP algorithm, by incorporating the determined frequency as prior information constraint，can extract the amplitude and phase of the weak signal effectively. The simulated experimental results show that, for the weak signal extraction, the proposed approach can improve signal to noise ratio (SNR) up to 30dB and especially suitable for low SNR environment extraction (i.e. SNR below -5dB). In addition to the traditional methods, this approach provides an alternative way for the weak signal extraction or detection.关键词：adaptive signal separation;frequency determined signal;weak signal extracting;null space pursuit3|15|0更新时间：2025-12-08
- 摘要：The description of plants appearance in nature is a hot topic in modern times. If save a plant graphics information in the form of a picture, the fineness of graphics depends on the storage format of the image and the amount of space it takes up. And it’s very difficult to realize the change to the graphics as a whole. By utilizing the computer language to model plant morphology can calculate and get plant graphics with only dozens of numerical, and it is easy to modify the whole graph. In the field of plant appearance modeling, fractal geometry can use the self-similarity of graphs to describe the natural appearance of plants better. Chaos theory, which is nonlinear as same as fractal geometry, also plays an important role in the description of natural objects. To improve the precision of object rendering, this paper proposed a plant morphology modeling algorithm based on theory of the fractal geometry and chaos. The uncertainty of chaos is utilized to the operation of fractal geometry. The probabilities of entering a periodic orbit are set. And then the system does the calculations based on the periodic orbitals that come in. A basic tree graph is drawn by this algorithm, and the thickness of tree trunk, the height of branch and density of tree are adjusted by adjusting the parameters in the affine transformation matrix, which verifies the feasibility of the algorithm. The experimental results demonstrated that the graph of plant drawn by this algorithm is close to the real object in nature and the algorithm is suitable for describing the object in nature.关键词：fractal geometry;nonlinearity;chaos theory;indeterminacy;plant morphological2|15|1更新时间：2025-12-08
- 摘要：At present, GLV/GLS scalar multiplication mainly focuses on the Weierstrass curves, attempting to find and construct more and more efficient computable endomorphism. In this paper, we study the applications of GLV/GLS method on Jacobi Quartic curve. Firstly, we present the concrete construction of efficiently computable endomorphism for this type of curves over prime field by exploiting birational equivalence between curves, and obtain 2-dimensional GLV method. Secondly, we consider the quadratic twists of elliptic curves. By using birational equivalence and Frobenius mapping between curves, we present methods to construct efficiently computable endomorphisms of this type of curves over the quadratic extension field, and obtain a 2-dimensional GLS method. Finally, we obtain the 4-dimensional GLV method on elliptic curves with j-invariant 0 or 1728 by using higher degree twists. The experimental results show that the speedups of 2-dimensional GLV method and 4-dimensional GLV method than 5-NAF method exceed 37.2% and 109.4% for Jacobi Quartic curves respectively. At the same time, under the three implementations above, the scalar multiplication on the Jacobi Quartic curves is always more efficient than that on the Weierstrass curves.关键词：elliptic curve;Jacobi Quartic curve;scalar multiplication;GLV method;GLS method;efficiently computable endomorphism2|12|0更新时间：2025-12-08
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The Authentication Protocol for Civil Navigation Message D2 of Beidou II Based on Identity Signature
摘要：The Beidou II civil navigation message D2(B-CNAV-D2) in Beidou navigation satellite system (BDS) are transmitted in an open channel without integrity protection, facing the threat of information being tampered and falsified, and vulnerable to spoofing attacks. In order to guarantee the integrity, authenticity and availability of B-CNAV-D2 information, based on the analysis of the composition structure of B-CNAV-D2, this paper presents an authentication protocol based on the identity signature to provide B-CNAV-D2 information source authentication and integrity protection. The authentication protocol is designed to achieve the functions of anti-tampering and anti-spoofing for B-CNAV-D2. The application of authentication protocol in B-CNAV-D2 can effectively reduce the processing steps of digital certificate distribution and update in traditional signature authentication schemes, improve the overall efficiency and authentication efficiency, and has better performance in authentication timeliness, and lower computing and communication costs.关键词：Beidou II civil navigation message D2;information source authentication;integrity;anti-spoofing;tamper-proof4|15|1更新时间：2025-12-08 - 摘要：With the rapid development of Industry Internet of Things and AI technology, various complex software systems (CSS) are becoming more and more popular, and becoming one of the most important software development paradigms. Its inherent growth construction and adaptive evolution require CSS to be able to perceive and diagnose its own health status in real time, so as to ensure the quality of its adaptive evolution. The paper uses feature engineering and mining software repositories (MSR) technology to analyze the features that affect the health of open source CSS, and establishes a data driven perception model that can reflect the health status of open source CSS in real time and objectively. Furthermore, a self-diagnosis model that can assist open source CSS fault diagnosis is defined with reference to the quality control chart. Finally, through the model comparison experiment, it is proved that our model can evaluate the health of software more comprehensively and effectively because it integrates most feature of software development process.关键词：complex software system;mining software repositories;self-perception model;self-diagnosis model3|12|0更新时间：2025-12-08
- 摘要：The speckle phenomenon in synthetic aperture radar (SAR) images is caused by the mutual interference of backscattering signals of ground objects. Although it is similar to noise, it involves the scattering characteristics of ground objects. The scattering characteristics of the same ground object can be described by the speckle statistical distribution model. Therefore, in the process of noise reduction, the scattering information of the ground object contained in the speckle can be preserved by restoring the statistical distribution characteristics of speckle. Based on this idea, an iterative filtering method of SAR image based on speckle statistical characteristic preservation is proposed. The proposed method assumes that the statistical distribution function of a given SAR image is known a priori, namely the mixture Gamma distribution, and its distribution parameters can be estimated by the pixel values of the image. Then, the EM（Expectation Maximization） algorithm is used to segment the SAR image based on the mixture Gamma distribution, so as to obtain the homogeneous regions in the image. Subsequently, for different homogeneous regions, select the gray levels with larger fitting errors, calculate the densities of the pixels whose values are the gray levels according to the segmentation results, and judge whether they are abnormal pixels, and the abnormal pixels are filtered by Frost filter. Repeat above procedure until the histogram of filtered image fits the statistical distribution function well. Experimental results of GF-3 and Radarsat-2 SAR image show that, on the premise of maintaining image quality, the proposed method can not only obtain better statistical modeling results, but also suppress speckle well and achieve image denoising.关键词：Synthetic Aperture Radar (SAR);speckle reduction;image histogram;statistical distribution function;abnormal pixels detection;statistical characteristic preservation3|15|1更新时间：2025-12-08
PAPERS
- 摘要：Map matching is a necessary procedure for many trajectory data mining and various location-based applications.Map matching algorithms are continuously evolving with the development of positioning techniques and application requirements.Research on map matching has undergone several stages, from real-time GPS data map matching, to low-sampling rate GPS trajectories offline map matching, to recently non-GPS positioning data or high resolution map matching.Various advanced map matching algorithms have been proposed.However, there is a short of a complete review of recent map matching algorithms.To bridge this gap, this paper conducts a comprehensive survey on map matching algorithms proposed in the last decade.A general framework of map matching algorithms is extracted, and spatial or spatial-temporal features commonly used in these algorithms are summarized.From the technical perspective, the HMM is the most commonly-used model in existing algorithms, before the maximum weights model.The deep learning technique has been recently applied into map matching, and is becoming a future trend for high resolution map matching.关键词：map matching;road network;trajectory data;HMM;CRF;route inference9|14|9更新时间：2025-12-08
- 摘要：The energy efficient ethernet (EEE) is a current standard that addresses the increasingly severe problem of large energy consumption in Ethernet. The strategies of EEE and their parameter configurations determine the time of EEE entering and the exiting low power idle states, which is crucial to both delay and energy consumption. Recent years, a large number of energy‑saving strategies of EEE have been studied at home and abroad. This paper surveys the energy‑saving strategies of 1/10Gbps and 40/100Gbps EEE. At first, it analyzes the strategies of 1/10Gbps EEE from the perspective of strategy design and modeling analysis. Subsequently, the main ideas of 40/100Gbps EEE strategies are presented. As a step further, the advantages and disadvantages of various EEE strategies in state selection, energy‑saving duration, and state transition period are compared and analyzed. Finally, the challenges and opportunities faced by EEE strategies in network traffic distribution, load status, and user latency requirements are discussed.关键词：ethernet standards;EEE;energy saving strategy;low power idle state;M/G/1 model;energy consumption of ethernet;traffic load3|15|0更新时间：2025-12-08
- 摘要：Sparse representation is a theory to study the essential problem of signal concise representation and precise recovery. It can better reveal, distinguish and extract the characteristic information contained in underwater acoustic signals，so that it has great advantages and potential in many applications of underwater acoustic signal processing. In this paper, the sparse representation theory and its application in underwater acoustic signal processing are reviewed. Firstly, the sparse representation model and typical sparse decomposition algorithms are introduced. Then, the key problems of sparse representation, such as adaptive over-complete dictionary design and off-grid processing and so on, are studied. Thirdly, some important applications of sparse representation theory in underwater signal processing are explored, which include high-resolution DOA estimation, micro-Doppler feature extraction of underwater target, angle-Doppler acoustic imaging of moving target, compressed sensing and reconstruction of underwater acoustic signals. Finally, the development trend of sparse representation theory in underwater acoustic signal processing is pointed out. Some necessary computer simulations are carried out to extract the multi-dimensional information features of underwater target in time, frequency and spatial domain are successfully extracted, and two kinds of typical communication signals are effectively compressed and accurately reconstructed.关键词：underwater acoustic signal;sparse representation;feature extraction;compressed sensing8|18|2更新时间：2025-12-08
SURVEYS AND REVIEWS
- 摘要：Using the ensemble learning algorithm to solve the secure relay selection problem can reduce the real-time processing delay and computational complexity, when the wireless systems that with fast-changing channel state information (CSI) or multi-hop relay situation. The secure relay selection problem of a full-duplex relay system is modeled as a multi-class classification problem, which is solved by the random forest (RF) algorithm. The CSI of the legitimate channel and eavesdropping channel is taken as the input of the training model, and the index of the relay node which can maximize the system security capacity is taken as the output of the training model. The implementation of the proposed scheme is divided into three phases: training data preparation, model building and result prediction. In the training data preparation phase, as the input features demanded by the RF algorithm are discrete values, feature extraction methods based on both uniform and non-uniform quantization algorithms are proposed to transform the CSI into finite discrete values. Finally, simulation experiments are conducted to verify the performance of the proposed scheme.关键词：full-duplex;relay selection;physical layer security;machine learning;ensemble learning;random forest3|12|1更新时间：2025-12-08
- 摘要：We devote to studying one‑weight ZpZp[u]‑additive codes, where p is an odd prime number. We derive a MacWilliams‑type identity that relates the weight enumerators of a ZpZp[u]‑additive code with its dual, and obtain a lower bound for the minimum distance of dual codes of one‑weight additive codes. Some structural properties of one‑weight ZpZp[u]‑additive codes are considered. By the Gray map, we obtain a family of optimal one‑Hamming weight p‑ary codes from one‑weight ZpZp[u]‑additive codes, which attain the Plotkin bound and Griesmer bound. Additionally, we describe some constructions of one‑weight ZpZp[u]‑additive codes.关键词：one‑weight codes;linear codes;additive codes;dual codes;MacWilliams identity2|14|0更新时间：2025-12-08
- 摘要：A topology of high-efficiency single-phase full bridge resonant soft-switching inverter is proposed to improve efficiency of single-phase full bridge inverter. The auxiliary circuit is connected with the bridge arm of the inverter and contains only one auxiliary switch and a small number of passive devices. The main switches and auxiliary switch can achieve soft- switching in the working process of the inverter. High-efficiency operation of the inverter can also be achieved by reducing switching loss. In this paper, the working process of the circuit is analyzed. The experimental results indicate that the switching devices can achieve soft-switching, which lays a technical foundation for further research and development of a new practical single-phase full bridge soft-switching inverter with high performance.关键词：inverter;auxiliary switch;soft-switching;efficiency;resonant pole2|16|1更新时间：2025-12-08
- 摘要：Terahertz detection and imaging technology are the foundation and key to promote terahertz technology development. In order to realize high sensitivity terahertz detection and imaging, a mesa-type silicon-based blocked-impurity-band (BIB) terahertz detector is designed. The structure and detection mechanism of the detector are introduced in detail. The preparation processes are presented briefly. A series of its photoelectric performances are investigated. A blackbody responsivity test system is built. The results show that at 4.2K temperature and 3.8V bias, its peak responsivity reaches 55A/W, and the response spectrum covers the frequency range from 6.7~60THz. In addition, a scan imaging system is set, and the high-resolution passive imaging is achieved. The imaging result shows that the spatial resolution and the temperature resolution of the imaging system can reach about 400μm and 7.5mK, respectively.关键词：blocked impurity band;terahertz detector;peak responsivity;scanning imaging;resolution2|13|1更新时间：2025-12-08
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