最新刊期
卷 45 ， 期 12 ， 2017
- 摘要：SAR (Synthetic Aperture Radar) despeckling is one of the key technologies in SAR image processing.This paper proposes an efficient despeckling algorithm based on optimized nonlinear diffusion model,which exploits the trainable nonlinear reaction diffusion framework.For the despeckling task,we train the parameters of linear filters and the influence functions,taking into account the speckle noise statistics of the intensity SAR image.Experimental results show that the proposed method provides comparable or even better results in comparison with PPBit and SAR-BM3D.Meanwhile,our proposed model is of high computation efficiency,and is well-suited for parallel computation.关键词：SAR intensity image;despeckling;optimized nonlinear reaction diffusion model;convolutional neural networks277|501|0更新时间：2025-07-16
- 摘要：The existing integrated navigation systems have lots of problems:the resolution of the terrain aided navigation system is low; the GPS signals of the GPS/INS navigation system are susceptible to be interfered; the SAR system has no ability of three-dimensional localization,and it cannot inverse the attitude of the platform.Aiming at the above problems,this article presents the method of InSAR/INS integrated navigation system based on the fringe matching.In the integrated navigation,we can obtain the location shift by matching two interference fringes,one is produced by InSAR system and another is generated by the digital elevation database.With the aid of the location shift we can inverse the attitude and position information.The location shift and the IMU information are set to the combined filter to obtain the navigation output.The InSAR/INS system has the following advantages:the interference fringes include the terrain and the attitude information of the platform; the interferometric phase is susceptible to the roll angle and we can inverse the roll angle by the phase with high precision; the InSAR system has the ability of three dimension localization.In this article,we introduce the theory and method of the InSAR/INS integrated navigation based on fringe matching.At last,we verify the validity of fringe matching and the inversion of observation volume by simulation and real data.关键词：InSAR/INS integrated navigation;fringe matching;the inversion of observation volume;combined filter180|328|0更新时间：2025-07-16
- 摘要：To effectively overcome the influence of model mismatch on the performance of adaptive beamformer,a modified iterative robust adaptive beamformer is proposed.Based on the integration of steering vector within or without the angular sector of desired signal's direction of arrival (DOA),a new stopping criterion is constructed in the proposed algorithm.Using the new stopping criterion,the weak robustness against stopping criterion parameter in iterative diagonally loaded sample matrix inverse (ILSMI) robust adaptive beamformer is strengthened,and the output signal-to-interference-and-noise ratio (SINR) is improved obviously.Simulation results show that the proposed algorithm can effectively improve the robustness of beamformer against different types of model mismatch.Moreover,the proposed algorithm can deal with DOA mismatch in large region,and the robustness against the angular sector of DOA is quite strong.关键词：beamforming;robust;diagonal loading;iterative110|304|1更新时间：2025-07-16
- 摘要：The regularized orthogonal matching pursuit (ROMP) has two drawbacks,ie,the sparsity should be known beforehand and once the atom is determined it can not be deleted.According to these two problems,this paper presents an improved ROMP channel estimation method based on compressive sensing by exploiting the sparse structure of channel impulse response.The proposed method combines the advantages of compressive sampling matching pursuit (CoSaMP),sparsity adaptive matching pursuit (SAMP) and variable step size to achieve the reconstruction of sparse signal quickly and accurately.Simulation results demonstrate that compared with the channel estimations respectively based on OMP,ROMP,CoSaMP and SAMP,the proposed method effectively improve the performance of the MIMO-OFDM systems in the normalized mean square error (NMSE) and bit error rate (BER).关键词：multiple input multiple output (MIMO);orthogonal frequency division multiplexing (OFDM);compressed sensing;greedy method;channel estimation332|413|2更新时间：2025-07-16
- 摘要：By using multi-source and multi-temporal remote sensing images,a ground object information recovery algorithm for thin cloud contaminated remote sensing images is proposed by combining classification with transfer learning.Firstly,multi-resolution decomposition of multi-source and multi-temporal remote sensing images is performed by using multi-directional nonsubsampled dual-tree complex wavelet transform.The decomposed high frequency coefficients of the ground objects of the thin cloud images are primarily classified by using Bayesian method.Then the transfer least square support vector regression model is trained to obtain the model parameters by using the domain adaptive learning of the low frequency coefficients of each class of ground objects.Finally,the low frequency coefficients of the thin cloud-contaminated images are predicted by using those of the cloudless reference images.The thin clouds are removed and the ground object information of the thin cloud contaminated images is recovered.Experimental results show that the ground objects recovered by the proposed algorithm have clear spatial details and small spectral distortion.Especially for the thin cloud contaminated remote sensing images with seasonal variation of ground objects,the proposed algorithm can effectively recover the ground object information contaminated by thin clouds.关键词：remote sensing image;information recovery;image classification;transfer learning129|440|2更新时间：2025-07-16
- 摘要：In cloud storage environment,client-side data deduplication can detect duplicated files at local,so as to save storage space and network bandwidth effectively.However,client-side deduplication still faces many security challenges.Firstly,since the file hash value is regarded as the evidence of duplication detection,the attacker is likely to obtain a whole file via a hash of the file.Secondly,to ensure the privacy of data,convergent encryption has been widely used in data deduplication technology,but the data itself is predictable,so that convergent encryption still inevitably suffered from violence dictionary attacks.To solve problems mentioned above,this paper uses blind signature to construct a secure key generation protocol,by introducing a key server to achieve the secondary encryption of keys,which efficiently prevents violence dictionary attacks.Furthermore,we propose a Proof of Ownership method based on block key signature.It can effectively prevent the attacker from obtaining the file through a single hash value and can realize the file-level and block-level deduplication of the encrypted file simultaneously.Meanwhile,the security analysis shows that our scheme can be proved to be secure in the random oracle model and can meet the security properties such as convergence key security,tag consistency and anti-violence dictionary attacks.In addition,compared with the existing schemes,the experimental results show that the computational overhead of our scheme is relatively small in terms of file upload and file deduplication.关键词：client deduplication;convergent encryption;blind signature;proof of ownership182|309|0更新时间：2025-07-16
- 摘要：The security of traditional wireless communication is mainly dependent on the upper layer encryption mechanism,which cannot protect the physical layer modulation mode and the modulation information security.This paper proposes a physical layer encryption modulation method for the orthogonal frequency division multiplexing (OFDM) system.In this method,the phase random signal is used to detect and extract the equivalent channel phase information,then the 3D (Three-Dimensional) constellation is modulated in the physical layer,followed by the receiver's decryption and demodulation.The scheme makes full use of the wireless channel phase response of randomness,reciprocity and location sensibility,and this characteristic is used to enhance the safety of physical layer signal.Theoretical analysis and computer simulation results show that the algorithm is secure,and compared with the traditional QPSK (Quadrature Phase Shift Keying) modulation,the BER (Bit Error Rate) of the proposed algorithm improves about 2.5dB.This paper focuses on the physical layer security,which aims at providing a new security for the physical signal layer,and has a wide application prospect in the future 5G communications and military security communications.关键词：three-dimensional mapping;constellation rotation;OFDM;channel detection;secret key extraction;physical layer encryption301|321|6更新时间：2025-07-16
- 摘要：Compared to the conventional two-step (including direction finding and position estimation) localization mechanism,the direct position determination (DPD) approach presented by Weiss and Amar has lower estimation errors and stronger resolution capability.Moreover,this technique provides a more convenient way to incorporate the signal waveform information.In this paper,the theoretical performance of the DPD algorithm presented by Weiss and Amar (called Weiss-Amar algorithm) is studied analytically.The asymptotical consistency is proved and the closed-form expression of the estimation variance is derived based on the error perturbation analysis method.It is also noted that the localization accuracy of this algorithm will decrease if the signals are correlated with each other.In order to solve this problem,an improved DPD algorithm is proposed for the case of known waveforms.In the new algorithm,the position parameters of all targets are considered as a whole to be estimated by using the alternating projection iteration.The performance improvement compared to the Weiss-Amar algorithm is remarkable for correlated signals.Furthermore,the Cramér-Rao bound (CRB) on the direct position estimation in presence of known waveforms is also deduced.Simulation results corroborate the effectiveness of the theoretical analysis and the advantage of the proposed algorithm.92|217|8更新时间：2025-07-16
- 摘要：In order to keep the analog to digital converter's speed and precision,a sample-and-hold(S/H) circuit for a 12-bit 40-MS/s pipeline ADC is designed and fabricated using a 0.18 micrometer process.The proposed amplifier can simplify the design and occupies smaller area.The substrate bias effect of the switch transistor used in the bootstrapped switch can be eliminated with the silicon-on-insulator (SOI) process,which can increase the linearity of bootstrapped switch and improve the performance of the S/H circuit.The S/H circuit occupies an area of 0.023 square millimeter.Measurement results show that the S/H circuit operates at a 1.5 V supply and consumes 3.5mW,and the spurious free dynamic range is 76.85 dB for a 1 MHz input signal with 40 MS/s sampling rate.The S/H circuit meets the requirement of the 12-bit 40-MS/s pipeline analog to digital converter.关键词：S/H circuit;SOI process;amplifier;bootstrapped switch;SFDR184|260|1更新时间：2025-07-16
- 摘要：The safety analysis model of critical system is essentially a mixed model of both discrete variables and continuous variables.The traditional analysis methods can only deal with the system based on discrete distribution or exponential distribution,so these methods are incapable of analyzing the safety of the hybrid system.To solve the problem,this paper presents a novel safety analysis method of hybrid system on hybrid Bayesian network(HBN).First,by using the Dirac function and unit step function to represent the deterministic relation and timing sequence of nodes in DFT respectively,we convert the DFT into a Bayesian network(BN).Second,The HBN with k-piece and n-degree polynomials is proposed to represent the DFT,in which the different failure distributions of nodes are fitted by piecewise polynomial functions.Finally,the inference algorithm of HBN is proposed.The experimental results show that the presented method can effectively solve the safety analysis of hybrid system.关键词：hybrid system;dynamic fault tree;hybrid Bayesian network;safety analysis138|283|1更新时间：2025-07-16
- 摘要：The disturbances caused by the instability of probe hold and the breathing exercise from subjects,are introduced during B-ultrasound examination.It decreases the measuring accuracy of the arterial wall displacement obtained from the B-Mode images by speckle tracking method.Thus,we propose a global rigid-registration method based on phase images of B-Mode images to eliminate these external disturbances.The phase features are obtained from B-Mode images via Riesz transform and difference of Gaussian filters.To improve the speed of searching optimization and the registration accuracy,a stepwise registration method is applied based on position weighted principal axis and centroid method combined with mutual information.The results show that,compared with these schemes of extracting wall displacement directly from B-Mode or phase images by speckle tracking method,this scheme can effectively remove these disturbances,and significantly improve the estimation accuracy.The proposed method can also be used in image registration of cardio-cerebro diseases.关键词：B-Mode ultrasound;vessel wall pulsatile detection;rigid registration;phase feature;principal axis and centroid method;speckle tracking;mutual information;speckle reducing anisotropic diffusion200|285|1更新时间：2025-07-16
- 摘要：Seeing that the processing time is uncertain in the actual manufacturing workshop,a multi-objective fuzzy flexible job shop scheduling model is established,and then an effective multi-objective evolutionary algorithm (MOEA) is proposed to solve this model.First,a method of mixing different machine allocation and operation sequencing strategies is adopted to generate initial population and a well-designed greedy inserting algorithm is adopted for chromosome decoding.Second,a Pareto dominant relation based on possibility degree and a modified crowding distance measure in decision space are defined and further employed to improve the fast nondominated sorting.Moreover,a problem-specific local search based on fuzzy critical path theory is incorporated into MOEA.Afterwards,the influence of key parameters is investigated based on the Taguchi method of experiment.Finally,extensive comparison with three existing algorithms is carried out,and the results demonstrate the effectiveness of the proposed algorithm.关键词：fuzzy flexible job shop scheduling;local search;multi-objective evolutionary algorithm;possibility degree;fuzzy critical operation268|393|4更新时间：2025-07-16
- 摘要：Previous approaches on integrated circuit parametric yield estimation usually model chip performance by pre-setting variation basis functions.It is easy to result in high complexity.On the other hand,random reduction of the number of the basis functions may result in accuracy loss.In order to avoid the issues,a sparse estimation approach for chip-level parametric yield is proposed.Taking power yield as an instance,the proposed approach models leakage power stochastically.Then according to the importance level,several key basis functions are adaptively selected to constribute a sparse leakage power model based on elastic net.Finally according to Bias theory and Markov chain method,the power yield is estimated efficiently.Experimental results show that the proposed approach not only makes the established power model general and sparse,but estimates the power yield accurately.Comparing to Monte Carlo(MC)simulation,the relative errors of power yield estimation based on proposed method are less than 5%.In addition,this approach can lead to a large cost reduction compared with MC simulation,and thus has higher efficiency.关键词：parametric yield estimation;sparse representation;elastic net;Markov chain;saddle point estimation103|198|0更新时间：2025-07-16
- 摘要：Aiming at the problem that the traditional image annotation model has long training time,sensitive to low-frequency words and other issues,this paper proposes a new automatic image annotation method based on Monte-Carlo dataset balance and robustness incremental extreme learning machine. First of all,training images of the public image library are segmented into different areas by this model and corresponding seed markup words are selected after segmentation,the areas are matched automatically based on comprehensive distance algorithm and the different keywords represent different areas. Then,for the huge difference of different annotated words' sizes in the public database,the Monte Carlo data set equalization algorithm is proposed to make the data size of each annotated word much the same. And a multi-scale feature fusion algorithm is proposed to extract effective features from different annotated images. Finally,the robustness incremental limit learning is proposed to improve the accuracy of the discriminant model for the problems of the consistency of the hidden layer nodes and the input vector weights existing in the traditional limit learning machine. The experimental results show that:compared with traditional algorithms of image automatic annotation,the methods proposed in this paper can implement the automatic image annotation quickly,and it is robust to low frequency words,and it is higher than most popular models of automatic image annotation in terms of average recall rate,average accuracy rate,comprehensive value and so on.关键词：Monte-Carlo data set balance;multi-scale feature fusion;extreme learning machine;automatic image annotation136|272|1更新时间：2025-07-16
- 摘要：Based on analysis of the principle in setting speed regulation for strip coiler,according to the actual problem that the acceleration and vibration factors of rolling mill induce the fluctuation of coiling tension,a novel tension control model is proposed.Under the condition that without real-time sensors of rolling torque and speed,combining with the idea of load observation and active speed complement,an improved direct torque control(DTC) system,which has strong ability of disturbance rejection,is designed for the first time.The experiment results show that the active speed compensation method can overcome the inherent defect of the common direct torque control system.Signals of speed fluctuation and torque in the asynchronous motor are decoupled.And constant tension in coiling process is achieved.关键词：coiler;speed regulation;DTC;observer;active compensation95|473|0更新时间：2025-07-16
- 摘要：A subgridding technique based on spatial filtering-Finite Difference Time Domain (SF-FDTD) method is proposed in this paper,the Courant-Friedrich-Levy (CFL) stability condition of the conventional FDTD algorithm can be improved by filtering operation in spatial frequency domain,thus obtaining a high stability FDTD method.The SF-FDTD algorithm is further applied to the subgridding technique,so that the time step of the subgridding region is the same as that of the coarse grid which greatly improved the computational efficiency.The numerical results show that the algorithm has high accuracy and validity in solving the electromagnetic problem with fine structure.关键词：spatial filtering;FDTD method;subgridding technique;stability condition202|262|1更新时间：2025-07-16
- 摘要：This paper proposes an estimation of distribution algorithm based on Copula for solving parallel machine scheduling problem with constrained waiting time.By considering the ratios of each class of orders to total lots as variables,a Copula function is constructed for each machine,and then the probability model of the dominant population is established.This algorithm generates individual coding vector group by sampling based on the probability model,and preserves the relative location information of the parent population.The time complexity of the proposed algorithm is analyzed,which increases logarithmically as the number of lots raises.Simulation results based on some instances and comparisons with some existing algorithms demonstrate the effectiveness and robustness of the proposed algorithm.81|237|2更新时间：2025-07-16
- 摘要：The design of stream architecture cryptography processor bases on the need of cryptography applications for information security equipment and fuses the basic structure of stream architecture processors.The paper basically researches and designs stream memory system which is a bottleneck that affects the processor's performance.The system aims at memory characteristics of the dedicated cryptography processor and takes reconfigurable design to satisfy cryptography applications' flexible and efficient requirements on the processor's memory system.Meanwhile,the design combines hierarchical-distributed-banked memory、parallel stream access of channels and stream access dispatcher strategy together,which optimizes memory access efficiency of the system to improve the whole performance of the processor.Research results demonstrate that comparing with the memory design of typical cryptography processors,memory access efficiency of this design can be highly raised to 6 times.关键词：cryptography processor;stream architecture processor;stream memory system;reconfigurable127|191|0更新时间：2025-07-16
- 摘要：Aiming at the different features between infrared imagery and visible images,a new fusion algorithm of infrared imagery and visible image based on Non-subsampled Shearlet Transform (NSST) is proposed.Firstly the algorithm decomposes infrared and visible light image that have been registered by NSST,getting the low-frequency subband images and the scale of each direction high frequency subband images;Then the low frequency subband images use a low frequency fusion rules based on the significant figure,and combined with human visual characteristic,high frequency subband image adopt a fusion rules of improving regional contrast;Finally,get fusion image by making NSST inverse transformation for the fusion of low frequency subband image and high frequency subband images.Experimental results show that the proposed algorithm can effectively synthesize the important information of infrared and visible images,and the fusion effect is better than that of the general image fusion method based on NSCT and NSST.关键词：image fusion;infrared and visible images;non-subsampled shearlet transform;saliency map;contrast220|332|15更新时间：2025-07-16
- 摘要：In this paper,firstly,the syntax and semantics of GPoFLTL(Generalized Possibilistic Fuzzy Linear Tempora Logic)are given,especially,both the path and language semantics of GPoFLTL are discussed.It is shown that GPoFLTL is the extension to GPoLTL(Generalized Possibilistic Linear Tempora Logic) with respect to fuzzy time,and that GPoFLTL has the stronger expression power than GPoLTL illustrated by some examples.Secondly,GPoFLTL model checking based on the generalized possibility measures is discussed using fuzzy matrix operator,which includes some fuzzy time temporal,"Soon","Nearly always",etc.Finally,the necessity threshold model checking problem of fuzzy linear time properties with fuzzy time temporal is studied; furthermore,the algorithm of the necessity threshold model checking of GPoFLTL based on automata method is given,and the time complexity of this method is proved.关键词：fuzzy time temporal;possibility property;linear temporal logic;time complexity;threshold model checking132|190|6更新时间：2025-07-16
- 摘要：Optimal hyperplane tendency and a large number of positive sample misclassifications often appear when the standard support vector machine (SVM) is employed to classify unbalanced data.So several causes and corresponding countermeasures for the perspective of SVM misclassifying unbalanced data are discussed.Considering the characteristics of SVM that optimal hyperplane is only decided by a small amount of support vectors,a novel SVM mathematical model based on negative boundary sample cutting strategy is constructed.However,this model has better recognition performance on positive samples only when the "training-cutting" step of negative samples is carried out many times,which is a time-consuming process.To replace it with the equivalent cutting hyperplane technique which can cut more negative samples at one time,an unbalanced SVM algorithm coupling negative-samples cutting with asymmetric misclassification cost is proposed.To further enhance the classification ability of this algorithm on unbalanced data,an improved sine cosine algorithm (ISCA) is presented to optimize the biased constant of the cutting hyperplane.Experimental results verify the optimized necessity of the biased constant of the cutting hyperplane,the advanced optimization performance of ISCA algorithm and the outstanding recognition performance of the proposed algorithm on unbalanced datasets,respectively.关键词：unbalanced data;support vector machine;boundary sample;cutting hyperplane;asymmetric misclassification cost;sine cosine algorithm127|220|1更新时间：2025-07-16
- 摘要：Predicting user retweet behaviors is the basis of building the information diffusion model in micorblog social networks,and also is applied for a variety of fields such as public opinion monitoring,viral marketing,political campaign etc.In order to improve the accuracy of predicting user retweet behaviors,under the MRF (Markov Random Field) framework,the paper comprehensively analyzes the effects caused by user attributes,microblog contents,the constraints between user retweet behaviors and the group retweet priors,and constructs the corresponding energy function based on the logistic regression model to globally predict user retweet behaviors.Experimental results show user retweet behaviors not only depend on user attributes,and micorblog contents,but also are influenced by the constraints between user retweet behaviors and the group retweet priors in varying degrees.Compared to the traditional methods,our proposed method can accurately model user retweet behaviors and thus achieve satisfactory results.关键词：sina microblog;retweet predicting;energy optimization;logistic regression114|251|1更新时间：2025-07-16
- 摘要：The fitness assigned by user can easily make fatigue which causes insufficient evolution algebra and low optimization efficiency for interactive genetic algorithms.In this study,a method of interactive genetic algorithms with individuals' fitness not assigned by user is presented.First,the individuals could be divided into satisfied sets and not satisfied sets; then,the individuals satisfaction is determined through evaluation time; finally,the fitness is calculated based on the maximum entropy principle under the biggest satisfaction.In order to ensure protogene inheritance,the reserved elite individual is built by population elite genes.This method is applied to selection system of decorative wallpaper,and the results show that it can effectively reduce fatigue and improve the optimization efficiency.关键词：interactive genetic algorithms;maximum entropy principle;fitness;not assigned by user65|199|3更新时间：2025-07-16
- 摘要：In order to produce summaries of online comment text,this paper presents a novel sentiment summarization framework which can produce abstractive summary based on Opinosis graph and Markov random walk model.This framework first convert the original text into Opinosis graph and use the Opinosis graph to mine the features of the original text,which can be used to classify the sentences.And then this paper adds a sentiment layer upon the cluster-based conditional Markov random walk nodel,and this improved model can judge which sentiment polar of the sentences in the same cluster is representative and select the proper sentence to produce abstractive summary based on the factors of sentiment and cluster.Experimental results show that this framework has achieved better results in ROUGE(Recall-Oriented Understudy for Gisting Evaluation)value compared to the baseline algorithm.关键词：Opinosis graph;Markov random walk model;sentiment summarization142|277|3更新时间：2025-07-16
- 摘要：Role-based collaboration (RBC) is a software engineering and cooperative computing method.It can extract and classify information systems.Therefore,it can be applied to the fields such as system unit collaborative computing and working.From meta-theoretical perspective,the specification of groups,roles and agents is a critical element of RBC.In consideration of the relationships and hierarchies faced by groups,roles and agents,we propose a series of role playing logic systems (RPL) and their algebra models through by using substructural logic.The proposed logic systems are polynomial in complexity and in support of RBC.One can extend RPL systems and models to suit other appropriate applications,to support RBC to do all kinds of engineering applications and research development.关键词：role-based collaboration;group;role;agent;role playing logic238|254|1更新时间：2025-07-16
- 摘要：The matrix constant false alarm rate (CFAR)detector uses the geodesic distance between the correlation matrix of the test cell and matrix Riemannian mean of the reference cells to detect target according to the information geometry theory.Based on the one-to-one corresponding relations between correlation matrix and AR(Auto-Regressive) spectrum,an improved matrix CFAR detector based on AR model is proposed with the distance between two matrices changed by the distance between two AR spetrums.The proposed detector is of higher frequency resolution and detects the spectrum of wake vortex in whole,fully taking advantage of the Doppler information of wake vortex.The detection performance of the proposed method and traditional methods is compared by using actual measured wake vortex data.关键词：information geometry;AR model;geodesic distance;aircraft wake vortex188|251|2更新时间：2025-07-16
- 摘要：A novel active clamped resonant DC-link inverter is designed to solve the problem that clamped diode is under high voltage stress caused by coupled inductors that was tapped inductor method in passive clamped resonant DC-link inverters. The maximum voltage of the clamped diode in the clamped circuit did not exceed the maximum voltage of DC-bus voltage by using active clamped method. There is only one auxiliary switch in auxiliary resonant circuit, and it did not need to set clamped switch, so it is easy to control and the cost of hardware is lower. Besides, under the action of clamped circuit, the DC-link voltage could be clamped at 1.1~1.3 times of input DC-voltage, which reduced voltage pressure effectively. According to equivalent circuits under different stages, the paper analyzed the working process of the inverter. The experimental results demonstrated that switching devices achieved soft switching and efficiency by 96.5% under the rated power 3kW. Therefore, the proposed topology can improve efficiency effectively.关键词：inverter;resonant;clamp;coupled inductors;soft-switching97|193|6更新时间：2025-07-16
- 摘要：Moving target detection in complex environment is one of the key points and difficulties in radar target detection.It is necessary to develop theory and method of high time-frequency resolution,high efficiency for big data,and suitable for multi-signals analysis.In this paper,the concept of short-time sparse fractional Fourier transform (ST-SFRFT) is proposed in association with the advantages of classical time-frequency analysis and high-resolution signal processing in sparse domain.The ST-SFRFT is then used for radar moving target detection and parameter estimation,which can achieve high-resolution representation of time-varying signal and improve signal-to-clutter ratio as well.The detection performance of moving target in complex environment is improved.Real experiment using a marine radar was carried out and the results indicate that the proposed method shows distinct advantages in anti-clutter and parameter estimation over classical time-frequency-based moving target detection methods.关键词：radar moving target detection;sparse representation;time-frequency analysis;fractional Fourier transform;sparse time-frequency distribution356|628|11更新时间：2025-07-16
- 摘要：Carbon nanomaterials have many unique physical properties,such as extremely large thermal conductivity and ampacity.According to the ITRS prediction,carbon nanomaterials are the most promising candidate to replace the conventional silicon and copper as the electronic materials of choice for the next-generation integrated circuits.In this paper,the present status and future prospect of carbon-based passive devices are reviewed.The characterization of carbon-based nano-interconnects,including carbon nanotube and graphene nano-ribbon,are discussed.Furthermore,the carbon-based high-frequency passive devices,including on-chip inductors and capacitors,are briefly introduced.The potential applications of carbon nanomaterials in the thermal management of ICs are also discussed.关键词：carbon nanotube (CNT);graphene;copper-nanocarbon;interconnect;on-chip inductor;varactor;heat spreader112|340|1更新时间：2025-07-16
- 摘要：Both physics package and electronic system contribute to the short-term frequency stability of a rubidium atomic frequency standard (RAFS).The contribution of the electronic system to RAFS short-term frequency stability depends mainly on the phase noise of microwave chain.Structure and operating principle of a typical traditional microwave chain are analyzed,and the×9 frequency multiplier and the modulator are found to be main sources of noise.To depress phase noise of the whole microwave chain,a new type of×9 frequency multiplication chain is designed by using SBD (Schottky Barrier Diode) for multiplication and increasing carrier frequency of modulation.Test showed that the phase noise of the 90MHz output signal of the chain is reduced by more than 12dB,and contribution of the chain to the frequency stability of RAFS is less than 1.9E-13 at 1s.A short term frequency stability 3.53E-13(1s),1.27E-13(10s) and 3.97E-14(100s) of RAFS has been achieved by using the multiplication chain.关键词：Rubidium atomic frequency standard;frequency multiplication;frequency modulation;phase noise;frequency stability146|299|11更新时间：2025-07-16
- 摘要：A retrospective interference reconstruction (RIR) scheme was proposed for the uplink multi-cell multiple-input multiple-output (MIMO) cellular interfering network with delayed feedback.The main idea of RIR is to eliminate the inter-cell interference based on the delayed output feedback (OF).The received beamforming matrix is used to reconstruct the interference signal at each base station (BS).Each BS feeds the reconstructed OF back to its corresponding user.Subsequently,the corresponding user for each BS utilizes the delayed OF to precode information and sends the precoding information to its served BS.The precoding information is used to eliminate all interference signals at each BS.The achievable degrees of freedom (DoF),the achievable sum rate and the application conditions of RIR scheme were analyzed for the uplink multi-cell MIMO cellular interfering network with arbitrary number of cells.Experiment results show that the RIR scheme can provide significant DoF gain over the time division multiple access (TDMA) and the existing retrospective interference alignment schemes.关键词：multiple-input multiple-output (MIMO);cellular interfering network;output feedback;degrees of freedom;retrospective interference alignment228|258|2更新时间：2025-07-16
- 摘要：In the interest of estimating the human motion in 3D (3 Dimensions,3D) and its spatial position from multi-view silhouettes,an algorithm called Gaussion incremental dimension reduction and manifold Boltzmann optimization (GIDRMBO) is proposed.After the high dimensional data denoting human motion in 3D is divided into two subvectors,the two subvectors denote information of spatial position and pose respectively.The proposed algorithm takes the advantage of Gaussion incremental dimension reduction model (GIDRM) to reduce the dimension of samples of the two subvectors respectively,so that the low dimensional spaces and relevant mappings can be built,and the optimization of objective function matching silhouettes can be carried out to achieve the estimation through the manifold Boltzmann optimization in the low dimensional space.The proposed algorithm can utilize the prior informations from low dimensional data of the samples of the two subvectors respectively.It can skip the area of local optimization better during searching,and generate human motion in 3D and its spatial position which can match the original motion images of multi-view.By the comparison of some traditional particle filters in the experiments,the proposed algorithm has better performance in lowering estimation error,disambiguating the silhouettes and overcoming the transient occlusion.关键词：Gaussion incremental dimension reduction model (GIDRM);manifold Boltzmann optimization;human motion;silhouettes;subvector176|261|1更新时间：2025-07-16
- 摘要：Collaborative filtering (CF) recommendation algorithm is widely used in the field of e-commerce.The previous researches on CF focused on either rating prediction or ranking prediction.In order to take into account these two aspects,a collaborative filtering recommendation algorithm based on rating prediction and ranking prediction (Unified Recommendation Algorithm,URA) is proposed.URA shares common latent features of users and items in PMF (Probabilistic Matrix Factorization,rating-oriented) and xCLiMF (Extended Collaborative Less-is-More Filtering,ranking-oriented) algorithms,and PMF learns improved latent features of users and items in URA,so that URA improves the performance of ranking recommendation.Experimental results showed that our proposed URA Algorithm outperformed PMF and xCLiMF algorithms over evaluation metrics NDCG and ERR,and that the complexity of URA is shown to be linear with the number of observed ratings.URA is suitable for big data processing in the field of internet information recommendation.关键词：recommended systems;collaborative ranking;collaborative filtering;rating prediction;ranking prediction618|562|10更新时间：2025-07-16
- 摘要：To improve the forwarding performance of NFV (Network Function Virtualization) in general server,this paper comes up with a hardware based VNF (Virtual Network Function) packet processing acceleration structure which is called FARD (Function Adaptive and Resource Dividable hardware structure).FARD can implement the hardware acceleration of any function instance on the L2/3/4 layer with programmable parser and action processor.And FARD also supports the dynamic resource allocation and function isolation between different instances with dynamic division on match table.The results based on the NetFPGA-10G platform show that the FARD acceleration structure increases by nearly 60 times in packets processing throughput compared with VNF which is only implemented by software.关键词：network function virtualization;programmable hardware;common acceleration structure;dividable match table;resource division optimizing256|389|0更新时间：2025-07-16
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