最新刊期
卷 46 ， 期 1 ， 2018
- 摘要：A classification network coding retransmission approach based on the minimal set coverage is proposed to improve the single relay cooperative transmission efficiency. In this scheme, to make full use of the advantage of relay-assisted transmission, the lost packets of receivers are classified into two categories according to the packet reception status of relay node after the initial transmission, and then the packets are encoded for retransmission according to the category sequentially. For each classification, according to the corresponding status feed matrix to search for encoding opportunities and generate encoding packets, the encoded packets selecting procedure is abstracted as the set coverage problem, and the number of retransmissions is approached the minimum value by solving the minimal set coverage problem. In addition, to reduce the number of retransmission packets and improve retransmission efficiency, encoding opportunities between the two types of lost packet are further used to generate new encoding packets on the premise of not increasing the current number of encoding packets. The analysis and simulation results show the effectiveness of the scheme proposed.关键词：network coding;retransmission;scheduling;classification;set coverage190|3|0更新时间：2025-07-16
- 摘要：This paper makes an investigation of the performance of a hybrid satellite-terrestrial cooperative network (HSTCN). In this system, some terrestrial amplify-and-forward (AF) relays with fixed-gain are employed to assist the signal transmission from a satellite to a destination which is corrupted by multiple co-channel interferences (CCIs), and the satellite links experience Shadowing-Rician fading while the terrestrial links undergo Rayleigh fading. Then, by assuming that maximum ratio combining (MRC) is used at the destination, the output signal-to-interference-plus-noise ratio (SINR) is obtained. Afterwards, we derive the moment generating function (MGF) of the destination and then present the analytical average symbol error rate (ASER) expression for the considered cooperative system. In addition, to obtain further insights, we also develop the asymptotic ASER analysis on the diversity order and array gain. Finally, numerical results are obtained with the help of computer, which demonstrates the validity of the performance analysis and the impacts of shadowing parameters, relay number and CCIs on the considered HSTCN.关键词：amplify-and-forward relaying;hybrid satellite-terrestrial cooperative network;co-channel interference;shadowing-Rician;average symbol error rate236|13|2更新时间：2025-07-16
- 摘要：The method based on conformity of parity-check equation was improved for its defect that the front interleaver identification has a strong impact on all the interleaver behind.The improved algorithm designs an approach on account of the limited performance of the original algorithm. It uses the recognition reliability to find the error position of interleaver identification. And from the purpose of reducing the complexity, it uses Gibbs sampling method to get the conditional probability of some relevant information for error correction according to the memory feature of the encoder. Simulation results show that, the improved algorithm performs better than the original algorithm, and it only needs half of the data to achieve the same recognition performance under the condition of the same SNR and has 1dB SNR gain to achieve the same accuracy under the condition of the same amount of data.关键词：Turbo-code interleaver;the conformity of parity-check equation;the recognition reliability;Gibbs sampling method180|10|8更新时间：2025-07-16
- 摘要：This paper presents an IP address finding algorithm based on improved Grover algorithm. At present, Internet is full of massive information. The weblogs contain lots of valuable information that must be analyzed for useful detection like behavior pattern of user. And the user identifying is the previous work. In the past researching of user identifying algorithms, most results focus on the accuracy of identifying user instead of the performance. This paper shows two IP address quick searching algorithms, namely record expansion searching algorithm and record non-expansion searching algorithm based on Grover searching algorithm. The query complexity of the record non-expansion searching algorithm gets quadratic acceleration.关键词：user identify;quantum computing;big data;Grover searching algorithm;searching on unstructured database260|14|4更新时间：2025-07-16
- 摘要：Plane wave imaging has been widely used in many applications. It has high frame rate but relatively poor image quality. Coherent plane wave compounding (CPWC)is an imaging method of summing beamformed outputs of array elements from different plane wave firing events, which can significantly improve the quality. However, the coherence between the plane waves is out of consideration. In this paper, we proposed a novel method in which CPWC is weighted by the sign coherence factor (SCF-CPWC). Firstly, a vector is composed by the beamformed outputs of the multiple steered plane wave firings on the same image point. Secondly, the sign coherence factor (SCF)of the vector is calculated, and then employed to weight the corresponding output of CPWC to get the final imaging result. Both simulation and experimental results demonstrate that the proposed SCF-CPWC method has achieved a better performance than CPWC. Compared to CPWC, it can not only improve the lateral resolution, but also increase the anechoic cyst contrast.关键词：ultrasonic imaging;coherent plane wave compounding;sign coherence factor110|17|8更新时间：2025-07-16
- 摘要：The ambiguity range of the traditional stepped-frequency waveform is decided by the frequency step, which result in range aliasing. To solve the above problem, a compressive sensing-based anti-range aliasing method for random sparse chirp frequency-stepped (RSCFS) signal is proposed. In the method, the sub pluses are dechirped firstly. Then the echoes are treated as the measurement data of the equivalent bandwidth LFM signal. Secondly, the corresponding measurement matrix is constructed according to the random transmission mode of the sub pulses, and then the compressed sensing reconstruction model of the RSCFS signal is built. At the same time, the high resolution range profile can be obtained by the compressed sensing reconstruction algorithm. At last, the ambiguity range of the proposed method is analyzed, and the factors that influence the size of the ambiguity range and the parameter setting criteria are given. In this method, the range profile synthesis process of the RSCFS signal is regarded as the process of the equivalent bandwidth LFM signal. It can not only reduce the restriction of the carrier frequency step to ambiguity range, effectively overcome the range aliasing problem, but also improve the range profile synthetic performance. Simulation results show the effectiveness of the proposed method.关键词：compressive sensing;random sparse chirp frequency-stepped waveform;range aliasing;high resolution range profile95|3|0更新时间：2025-07-16
- 摘要：Firstly, this paper determines the period of ‘Interleaving’ sequences from de Bruijn sequences of n-stage and proves all 2n-tuple states are different from each other. Secondly, in the view of shift equivalence, the paper demonstrates that one can only construct two sequences from de Bruijn sequences of n-stage. For each one, the completion of its missing four 2n-tuple states can construct de Bruijn sequences of 2n-stage. Since there are two different ways to complete the missing bits, we can finally get four de Bruijn sequences of 2n-stage from one de Bruijn sequence of n-stage.关键词：stream cipher;de Bruijn sequence;interleaving method;shift equivalence129|8|3更新时间：2025-07-16
- 摘要：Aiming at the subjectivity of the time resource allocation and the low utility of the time resource in the air defense phased array radar, a novel online task interleaving scheduling algorithm was proposed by considering the internal structure of the task. On the basis of setting the importance and the urgency of the task into dynamic priorities, the algorithm can execute other task's transmitting period or receiving period during the task waiting period. The simulations show that the proposed algorithm significantly improves the successful scheduling ratio, the time utilization ratio, and the treat ratio of execution compared with the highest task mode priority and earliest deadline first (HPEDF) algorithm.关键词：phased array radar;scheduling algorithm;dynamic priority;interleaving scheduling107|7|2更新时间：2025-07-16
- 摘要：A sparse concentric ring array method based on 0-1 programming is proposed. Differential evolution algorithm is applied in the 0-1 programming. By obtaining multiple planes in the main lobe of the concentric ring array and assuming the side-lobe level, the beam width of the selected plane pattern and the element number of the array as the goal for optimization to reduce the cost of the concentric ring phased array. In order to validate the proposed method, a 9-ring and a 10-ring concentric circular array are calculated. The calculated results show that the element number of the 9-ring concentric ring array is reduced from 279 to 161, the side-lobe level is reduced from-17.4 dB to-20.8 dB, and the half power beam width increases by 0.22°. The element number of the 10-ring concentric ring array is reduced from 341 to 190, the side-lobe level is reduced from-17.4 dB to-23.9 dB, and the half power beam width increases by 0.79°.关键词：0-1 programming;sparse concentric ring array;differential evolution (DE) algorithm;low-cost phase array157|3|1更新时间：2025-07-16
- 摘要：Wireless Networks for Industrial Automation Process Automation (WIA-PA) is China's national standard for industrial wireless sensor networks. Deterministic scheduling is one of the key technologies for WIA-PA networks. However, current deterministic scheduling algorithms mainly focus on the common wireless sensor networks or WirelessHART and ISA100.11a networks, and they are not optimized for WIA-PA networks. Therefore, an optimal backtracking scheduling algorithm is proposed and achieves the optimal schedulable ratio for WIA-PA networks. And based on this, another deterministic scheduling algorithm called Least Slack First on Time Division Multiple Access (LSF-TDMA) is further presented. Simulation results demonstrate that LSF-TDMA algorithm can meet the deterministic demand of end-to-end data transmissions in WIA-PA networks. It obtains a near-optimal schedulable ratio while effectively reducing the algorithm complexity.关键词：deterministic scheduling;slack;industrial wireless sensor networks;WIA-PA networks348|12|11更新时间：2025-07-16
- 摘要：To evaluate the reliability of WSNs (Wireless Sensor Networks) in the malware spread scenario, the traditional epidemic model SEIR was extended by introducing a state "Dead" and the dynamic change process of sensor node states was exactly described by a Markov chain (MC). Using the stochastic game, a malware spread detection model for WSNs was proposed to predict the probability of malware adopting the spread behavior. The prediction results attained were integrated into the MC's state transition matrix in order to relate the malware intention to the MC randomness. An equation to compute a sensor node's reliability in the malware spread scenario was constructed via the MC, and reliability evaluation methods for WSNs with star or cluster topology were given. Experiments have shown the influence of malware's spread on sensor nodes' reliability and illustrated that the proposed method can efficiently evaluate the WSNs reliability.关键词：wireless sensor networks;malware;epidemic model;stochastic game;reliability119|7|3更新时间：2025-07-16
- 摘要：This paper is focused on the optimal policy selection for moving target defense. Attack-defense confrontation in moving target defense environment is analyzed. Reward quantization method of moving target defense policy is proposed. Single-stage and multi-stage moving target defense game models are constructed based on the dynamic game with incomplete information. The algorithm to obtain perfect Bayesian equilibrium and the method to revise prior belief are proposed. Optimal moving target defense policies are obtained under different security situations. Finally, not only the feasibility and effectiveness of the proposed model and method are illustrated and verified in a representative example but also general rules of network defense using moving target defense policies are summarized.关键词：moving target defense;policy selection;dynamic game with incomplete information;perfect Bayesian equilibrium134|8|30更新时间：2025-07-16
- 摘要：In order to improve the prediction accuracy and reduce the noise influence of link quality for wireless sensor network (WSNs), a link quality prediction algorithm based on improved kernel FCM and intelligent SVR (IKFCM-ISVR) is proposed. Firstly, the validity index based on compactness and dispersion is introduced into the kernel FCM (KFCM) method, which realizes the automatic division of cluster number for samples. Then the improved kernel FCM method is used to process the data of link quality, and the membership degree of sample clustering is obtained. On this basis, the SVR prediction model based on social spider optimization (SSO) algorithm is constructed, and the SSO based on dynamic refraction learning mechanism is used to optimize the parameters, getting the best combination of SVR parameters for different clustering. Finally the IKFCM-ISVR algorithm is used to predict the WSNs link data in different experimental scenarios. The simulation results show that, compared with other prediction algorithms, the prediction accuracy of the algorithm is improved by 36.8~68.4%.关键词：link quality prediction;kernel fuzzy C-means clustering;support vector regression (SVR);social spider optimization168|3|2更新时间：2025-07-16
- 摘要：Aiming at the classification performance deficiencies of current supervised learning algorithms on manifold data sets, e.g. low classification accuracy and limited sparsity, a sparse manifold learning algorithm based on sparse Bayesian inference and manifold regularization framework is proposed. The algorithm is called manifold learning based on sparse Bayesian approach (MLSBA). MLSBA is an extension of sparse Bayesian model, by introducing sparse manifold priors to the weights, which can effectively employ the manifold information of sample data to improve the classification accuracy. Extensive experiments are conducted on various datasets, and the results show that MLSBA not only achieves better classification performance on manifold datasets, but also has comparable effectiveness on the non-manifold datasets, and our algorithm has good sparsity on two categories of datasets at the same time.关键词：Laplacian;sparse Bayesian;sparse manifold prior;manifold regularization460|11|2更新时间：2025-07-16
- 摘要：Traffic congestion is more and more serious. Efficient route guidance has been the main way to relieve congestion. The existing research results mainly concentrate on optimizing single vehicle routing or multi-vehicles route guidance with small traffic network scale. There is no real-time and dynamic route guidance for large-scale multi-vehicles and multi-intersections. The current studies mainly have the following limitations: (1) the need for an appropriate metric or factor for the evaluation a route guidance project; (2) access to real-time route guidance for multiple vehicles in large scale multiple intersection urban networks. In view of the above problems, this paper proposes a route guidance quantum searching (RGQS) method for real-time dynamic multi-intersections in urban traffic network, which takes full account of various factors and provides real-time route guidance to avoid local congestion. The extensive experiments show that the RGQS method can reduce the traveling time by 20% compared with the comparison algorithms in the artificial road network and the real road network, respectively.关键词：traffic congestion;route guidance;multi-intersection;utility value;quantum search231|12|2更新时间：2025-07-16
- 摘要：Based on inheriting the advantage of global exploration of Comprehensive Learning Particle Swarm Optimizer (CLPSO), the Orthodox Local Search (OLS) approaches with efficient convergence are introduced and a Hybrid Particle Swarm Optimization algorithm with Adaptive starting strategy of Local Search based on Quasi-Entropy (ALSQE-HPSO) is proposed. A quasi-entropy index is utilized to solve the key issue of when to start OLS. The test results of 10-dimension and 20-dimension of eight benchmark functions show the performance advantages of the ALSQE-HPSO algorithm. The comparisons between the proposed algorithm and six other improved PSO algorithms, including two improved CLPSO algorithms and one PSO algorithm with OLS, are also made. The numerical results indicate that the performance of the ALSQE-HPSO is superior to the compared algorithms.关键词：evolutionary algorithm;particle swarm optimization;adaptive strategy;local search;population diversity235|14|3更新时间：2025-07-16
- 摘要：In order to solve the problem of fixed structure element in traditional mathematical morphology on graph space, the concept of similarity weight on graph space is put forward, and the adaptive structure graph is defined. The property of structure graph is analyzed and proved. The new adaptive morphological operator on graph space is advanced on this basis and the properties of the operator are put forward and analyzed theoretically. The new operator considers not only the local feature of image pixels but also the global features of continuous pixels. The experimental results show that the new operator is superior to existing color morphology in maintaining integrity and correlation of the image information, and can select threshold value and structure element according to the characteristics of the image, thus it has a broad application prospect in more sophisticated image processing aspects.关键词：adaptive morphology;graph space;structure element;similarity weight;extreme extraction algorithm;threshold value195|14|3更新时间：2025-07-16
- 摘要：The ship detection technology is of special significance in both military and civilian level. In order to detect ship targets quickly, efficiently and accurately in a wide and complex sea surface environment, a new method for ship detection based on multi-features and multi-scale visual saliency is proposed. This method makes full use of features of the hyper-complex images which can be operated simultaneously in a number of channels, save operation time, and guarantee the characteristics of different scale characteristics. First, the method uses top-hat algorithm for image preprocessing of the original image to suppress the interference of clouds and oil. Secondly, a variety of features are extracted to form hyper-complex images to detect the significance of ship targets. When we get the last saliency map, we segment ships to ensure the target location by using the OTSU algorithm, and then we mark the ship target in the original image. We make the experimental analysis in several sea conditions, and experimental results show that the algorithm can eliminate fog, cloud and grease interfering with accurate detection of ship targets. In this algorithm, true rate meets 96.52% and the false alarm rate is as low as 2.11%. Compared to other saliency detection algorithm in ship detection, this algorithm has obvious advantages.关键词：ship detection;visual saliency;PQFT algorithm168|3|13更新时间：2025-07-16
- 摘要：Sampling is an effective way to solve the problem of unbalanced data classification. According to the distribution of samples, we employ the three-way decision model to divide the universe into three parts:positive region, boundary region and negative region. After that, we oversample the minority class samples in boundary region and negative region respectively. Then, a novel oversampling algorithm for imbalance data based on three-way decision model, namely TWD-IDOS, is developed. The experimental results show that the proposed method can effectively solve the two-class classification problems of imbalanced data and has a better performance in such measures (Recall, F-value, AUC) on C45, KNN and CART classifiers than other oversampling methods.关键词：three-way decision;neighborhood rough set;boundary sampling;imbalanced data;SMOTE356|19|19更新时间：2025-07-16
- 摘要：At present, many researchers focus on identifying protein complexes in the dynamic protein-protein interaction (PPI) network. But most of the methods have been used in unweighted network, the accuracy is not high since they could not accurately describe the network topology characteristics. In this paper, we put forward the topology potential to construct the weighted network. A protein can be regarded as a physical particle in the network which has a virtual field around it, and the interaction of all proteins forms a topology potential field. By computing the value of topology potential between nodes, the weighted network is constructed, and Markov clustering algorithm is used to identify protein complexes. The experimental results compared with the classic algorithms on DIP data and Krogan data indicate that their precision and f-measure value are higher and the proposed algorithm is more suitable to identify the protein complexes.关键词：Protein-protein interaction network;the topology potential;Markov clustering83|21|9更新时间：2025-07-16
- 摘要：This paper studys model-checking problem for FCTL (fuzzy computation tree logic) over nondeterministic fuzzy system and shows that it can be solved in linear-logarithmic running time in the size of the system. Firstly, we introduce NFKS (nondeterministic fuzzy kripke structure) which is adapted to model nondeterministic fuzzy system. The syntax and semantics of fuzzy computation tree logic over NFKS are presented. For describing two kinds of semantic explanation, we use path quantifiers ∃sup, ∃inf and ∀sup, ∀inf as substitutes for an existential path quantifier ∃ and a universal path quantifier ∀ in the syntax of the CTL. Then, we study the model checking algorithm for fuzzy computation tree logic over NFKS. Furthermore, the improvement algorithms for FCTL formuleas ∃suppUq, ∀suppUq, ∃infpUq and ∀infpUq are given, whose time complexities are linear-logarithmic running time in the size of the system.关键词：model checking;computation tree logic;fuzzy logic;Kripke structure;temporal logic129|10|8更新时间：2025-07-16
- 摘要：The vibration signal of rolling bearing is a nonlinear and unstable signal. Therefore it is very challenging to carry out feature extraction accurately from the complicated data of non-periodic rolling bearing. This article hereby proposes a method of feature extraction based on local spectrum bearing data. This method combined the segmentation point obtained from pretreatment and the spectrum analysis, built localized feature of the data, determined the definition of the local frequency and the construction method of time-frequency domain, and implemented the feature extraction. Experiments show that this method overcame the limitation that Hilbert transform is only suitable to describe the narrowband signals. It also made up for the defects of Fourier global frequency which is only valuable to the infinite wave period signals. As a new method of feature extraction from the time domain data of the nonlinear and unstable rolling bearing, it reduces the false frequency and is compatible with the analysis of both time domain and frequency domain. It has very high practical value in the fault diagnosis of rolling bearings.关键词：fault diagnosis;rolling bearing;feature extraction;local spectrum;segmentation point119|10|5更新时间：2025-07-16
- 摘要：The observation equation has to be linearized for the multipath estimation algorithm based on Extended Kalman Filter (EKF).To tackle the problem of being sensitive to initial state, which leads to a performance degradation in terms of estimation accuracy, a new multipath estimation algorithm based on intelligent optimization is proposed.Through minimizing the second moment of the estimation error the multipath estimation problem is transferred into an optimization problem with constrained conditions.Furthermore, the instantaneous error is considered as a constrained condition as well as the prior information of the multipath parameters.Then, an intelligent optimization algorithm is used to solve the presented optimization problem.Especially, the ε Constrained Rank-based Differential Evolution (εCRDE) algorithm is adopted.In addition, the εCRDE algorithm is improved to cater for the need of iteration for multipath estimation.Simulation results show that the proposed algorithm outperforms EKF for multipath estimation in the case of single multipath and two multipaths.关键词：multipath estimation;optimization algorithm;differential evolution (DE);Kalman filter164|219|1更新时间：2025-07-16
- 摘要：Sparse multinomial logistic regression (SMLR) is an important supervised classification method for hyperspectral images (HSI). However, because the traditional SMLR based pixel-wise classifiers only use the spectral signatures, the good robustness and high classification accuracy are hardly achieved with a small number of samples without considering the spatial information of HSI. By using the kernel tricks, the kernel sparse multinomial logistic regression (KSMLR) method can partly overcome this limitation, however the resulted misclassification errors are still expected to be further reduced. According to the statistical analysis of classification errors resulted in KSMLR, we propose a novel two stage framework which combines KSMLR and error rejection for HSI classification. The proposed model, named KSMRL-TVL1, adopts the L1 norm to measure the heavy-tailed property of the classification errors so as to build the data fidelity term, and uses the total variation (TV) regularization term to measure the local spatial smoothness of the hidden probability field. The experiments on Indian Pines dataset and University of Pavia dataset show that the proposed method can better improve the robustness and classification accuracy.关键词：hyperspectral image;image classification;kernel sparse multinomial logistic regression;error rejection139|3|7更新时间：2025-07-16
- 摘要：The quasi optical polarization separation principle is introduced. The new type of wire grid calibration source consisting of polarized wire grid, artificial black body, and cold sky signal is designed. Through the rotation of the polarized wire grid, the radiation energy of artificial black body and cold sky is mixed. The wire grid calibration source provides varying temperature signals, and solves the problem of low-frequency radiometer calibration. A measured reflectivity of 98.4% and transmittance of 99.9% at L-band is demonstrated. The brightness temperature dynamic range of wire grid calibration source is between 8K and 248K, which meets the design goal.关键词：radiometer;Calibration;polarized wire grid;quasi-optical technology137|3|0更新时间：2025-07-16
- 摘要：In order to research the propagating rules of stress wave in piezoelectric ceramic composite structure (front substrate-piezoelectric ceramic-rear substrate) and characteristics of the output voltage for piezoelectric ceramics under strong shock loading. The Polyvinylidene Fluoride (PVDF) pressure test system, the output voltage test system and the one-stage light gas gun loading system were built by ourselves and used in the laboratory. Experiments were carried out by 2A12 aluminum cylindrical projectile at the velocities of 313m/s, 326m/s, 379m/s and 397m/s, respectively, against piezoelectric ceramic composite structures (rear substrates of different materials). The voltage signal generated by the PVDF pressure sensor between the piezoelectric ceramic and the rear substrate and the voltage output signal of the piezoelectric ceramic were collected. At the same time, based on the propagating theory of one-dimensional elastic wave, the relationship between the collision velocity and the pressure peak of the stress wave in the variable cross-section problem formed by the contact between the projectile and the piezoelectric ceramic composite structure is deduced. The stress peaks at the rear surface of the piezoelectric ceramic were obtained at different collision speeds based on the relationship deduced. The peaks of the voltage output for the piezoelectric ceramics are calculated by the theoretical relationship between the peak of output voltage for piezoelectric ceramic and the peak value of the impact pressure. The peak value of the shock pressure is obtained by the experimental data processing from the voltage signals measured programmed by Matlab. The results show that the peak values of the impulse pressure and the voltage output are basically consistent with the experimental results. When the impact speed is close, the material properties (plexiglas and aluminum alloy) of the rear substrate have a significant effect on the peak value of the stress pulse. The peak value of the stress pulse of the plexiglass as the rear substrate is higher than the peak value of the pulse stress when the rear substrate is an aluminum alloy. And the pulse duration of the plexiglass as the rear substrate is longer than the duration of the pulse when the rear substrate is an aluminum alloy. The peak value of the voltage output of the piezoelectric ceramic increases with the increase of the impulse pressure and it is non-linear.关键词：piezoelectric ceramics;Strong shock;PVDF;Transient high voltage173|10|3更新时间：2025-07-16
- 摘要：In the internal inspection of pipes based on Remote Field Eddy Current (RFEC), when transmitter passed by defects on pipe, signals tested by receivers is superimposed by the secondary peaks. Secondary peaks are caused by defects locate near transmitter, and lead to wrong assessment of qualification of defects. This paper applied dual receivers for removing secondary peaks. In proposed method, two receivers are set coaxially to transmitter in remote field to get two differential signals. With these two differential signals, Wiener deconvolution filter is employed to obtain secondary peaks and filter testing noise. Further, an array of sensors is set in remote field to test local defects. The secondary peaks can be subtracted from signals tested by sensors by using the dual-receiver. The feasibility of proposed method is validated by testing tool and experimental pipe.关键词：RFEC testing;defects detect;secondary peeks;Wiener deconvolution filter103|3|5更新时间：2025-07-16
- 摘要：A two-class text categorization method, active learning negative selection text categorization (ALNSTC) algorithm, based on active learning (AL) method and negative selection (NS) algorithm, is proposed for the problem of spam proliferation. The positive user interest set and the negative user interest set are established according to a small number of labeled samples. And the sampling engine (SE) of AL method is improved by the autologous anomaly detection mechanism of the NS algorithm. The two-way user interest sets are used as detectors, and a new sample set is employed as a self-set. The above two sets are matched with Hamming match rules. The classification process of each sample set is able to update the two user interest sets. The proposed algorithm is carried out with a full-scale test on six common spam corpus, which are selected as experimental material, and analyzed and compared with other five state-of-the-art spam classification methods, which are quick online spam identification (QOSI) method, semi-supervised collaboration classification algorithm with enhanced difference (DSCC), dynamic web spam filtering (WSF2) method, multilevel spam filtering algorithm based on artificial immunity (MSFA-AI), and integrated multi-field learning (MFL) method, in different evaluation metrics, such as precision, recall, ROC curve, categorization running time and the labeled number of spam. The results show that the proposed method has better precision rate, recall rate, classification accuracy, and can reduce the artificial labeled number of spam samples. It is advantageous to enhance the classification capacity of the algorithm that the user preferences are converted into positive and negative user interest sets. In addition, the user labeled number is reduced when unknown category features are obtained by the exception detection mechanism.关键词：text categorization;spam detection;active learning;negative selection;two-way user interest set244|4|11更新时间：2025-07-16
- 摘要：As a typical multi-radar data association metrics, the association method, which is based on the chi-square statistic metrics, is an effective way used for multi-radar data association in the current information fusion fields. It is found that, however, the correct probability of multi-sensor data association decreases as the radar measurement error decreases, when the target moves in a hypersonic way. In view of the strange phenomenon, the data association model, which is based on the chi-square statistic metrics, is established firstly by the linear frequency modulated radar. Then the influence of target hypersonic movement on multi-sensor data association is further discussed, and the conclusion is that the associated judgment function (subjected to the non central chi square distribution) is contradicted against the existing associated judgment threshold (subjected to the chi square distribution). Finally, the strange phenomenon above, which is proposed in this paper, is explained by using the statistic theories, and an important conclusion is correspondingly drew that the existing data association approaches, which are based on the chi-square statistic metrics, have a great disadvantage on multi-sensor data association of hypersonic target. Simulation results show that, the happening of the strange phenomenon above is reasonable, when the target moves in a hypersonic way.关键词：hypersonic;target;data association;LFM radar;tracking100|9|0更新时间：2025-07-16
- 摘要：The paper discusses the selection of orders of elements in one generator set for a specified group, and analyzes multi-discrete logarithm problems (MDLP) and a public key encryption scheme based on the MDLP. The paper points out that under the circumstances described by the original paper, the MDLP may be transformed into a discrete logarithm problem, which manifests that there exists a sub-exponential time solution for the MDLP, and causes a related private key insecure in sub-exponential time in most cases. Further, in almost any case, a ciphertext inversion problem may be transformed into a discrete logorithm problem, which illustrates that there also exists a sub-exponential time solution to the ciphertext. Therefore, to convert a discrete logarithm and the ElGamal cryptosystem into those which are resistant to the Shor quantum algorithm attack, the people still need to make deeper and longer explorations.关键词：multi-discrete logarithm problem;public key cryptograph;security;quantum algorithm;sub-exponential time solution180|11|1更新时间：2025-07-16
- 摘要：In order to understand the evolutionary mechanisms on social networks, we investigate the evolution of information sharing behavior on directed and dynamic social networks using social evolutionary games, in which agents aim to improve their short-term utility and long-term reputation by imitating the most successful strategy from their partners and adjusting their partnerships, respectively. The public goods game is used as a metaphor for the interactions of agents on social networks. The results of numerical simulations reveal the effects of the frequency of partner adjusting, reputation pursuit and group effects on the evolution of social networks. Finally, an application of social evolutionary games on SinaWeibo is conducted, which may help us understand the mechanism behind the evolution of social networks.关键词：social evolutionary game;social network;public goods game;information sharing behaviour;reputation156|7|4更新时间：2025-07-16
- 摘要：In view of the problem that the node energy consumption is not balanced and system survival time unbalanced, put forward a kind of energy consumption balancing communication system based on two-way relay (TWR) in Cognitive radio networks (CRN). The system consists of source node and destination node, two-way relay (TWR) and receiving nodes, each node distribute initial energy, through setting up reasonable transmitted power to achieve power normalization processing, balance the node energy, in order to prevent the part of the node perish due to run out of energy, to realize Cognitive radio network (CRN) node energy equilibrium and maximize survival of life. Simulation results show that the proposed based on the normalized energy equalization algorithm can maximize efficiency, extend the system survival time while improve the utilization ratio of energy.关键词：two-way relay;energy normalization;energy equilibrium;energy efficiency115|3|3更新时间：2025-07-16
- 摘要：Currently, the most common encryption scheme of cloud computing access control system is CP-ABE, but the conventional CP-ABE encryption did not deal with the issue of user's access permission; data owners only allow the users to read the data but not to write, such kind of coarse access control mechanism is not flexible and low efficiency. To deal with this issue, the paper proposes a Data Access Control scheme with access Permission for Cloud Computing (DACPCC), it sets permission control keys to encrypt the data in cloud based on CP-ABE; the data owner controls the data's access permission by choosing the permission control keys. The paper illustrates the design details of the proposed scheme, then theoretically proves the security and evaluates the performance through simulated experiments; the results show that DACPCC allows the data owners to control the access permission of the data, and it is safe and more efficient.关键词：cloud computing;access control;CP-ABE;access permission;attribute revocation254|15|2更新时间：2025-07-16
- 摘要：Under the background of big service, more and more resources are released and utilized in the form of services. Meanwhile, the users' requirements grow in complexity, which leads to the exponential growth of the service composition calculation scale. In this paper, a task-granulating algorithm called TgA is proposed to solve large-scale service composition optimization problem quickly and effectively. Firstly, we build a hierarchical service composition model based on task granulation, and analyze its computational complexity. Secondly, we analyze the feasibility theoretically during the task-granulating according to the calculation of existing QoS attributes. Finally, a large number of simulation experimental results show that, compared to the classical particle swarm optimization (PSO) algorithm, the proposed algorithm can improve the service composition optimization performance by 4 to 7 times and increase the optimization accuracy by more than 10%.关键词：service composition (SC);task granulating;hierarchical model;PSO268|13|0更新时间：2025-07-16
- 摘要：At present, more and more people pay attention to space debris detection, and the completion of the Qujing incoherent scattering radar has further accelerated the pace of China's space debris detection. Based on basic characteristics of this radar, firstly Mie theory is used to study the scattering characteristics of an ideal spherical target at 498MHz, 500MHz and 502MHz, respectively, the results show that most scattering energy distribute in and near the forward direction;For space debris cataloged by 14209, we obtained its radar cross section (RCS) 0.0043m2 and gave the minimum detectable object for this radar, which indicated that the radar had excellent performance in space debris detection, and the calculation was precise and could meet the needs of the project. Finally, through the example of 7.3m and 1m antenna in Xi'an, we analyse the conclusion, which is valuable for optimize embattle and network detection of space debris.关键词：electromagnetic scattering;radar cross section (RCS);incoherent scattering radar;space debris292|10|0更新时间：2025-07-16
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