最新刊期
卷 44 ， 期 4 ， 2016
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A Low Complexity Acquisition Algorithm for DSSS Signal with Low SNR and Non-Coherent Data Modulation
摘要：A block acquisition algorithm based on parallel interval estimation is proposed for direct sequence spread spectrum (DSSS) signal with low signal-to-noise ratio (SNR) and non-coherent data modulation.First,the existence interval of data modulation offset is estimated in parallel with invalid data section abandoned against possible bit-flip.Then fast Fourier transform (FFT) and incoherent accumulation are adopted in the valid data sections of each estimation branch to acquire cumulative detection value of each frequency point.Finally,the constant false alarm rate detection and parabolic interpolation are performed on the maximum cumulative detection value to fulfill signal detection and parameter estimation.Both analysis and simulation demonstrate that by adjusting key parameters to match the requirement of false alarm and detection probability,acquisition time and SNR,the proposed algorithm achieves good performance with low computational complexity and resource consumption.关键词：non-coherent data modulation;low complexity;low SNR;parameter optimization235|2|3更新时间：2025-07-16 - 摘要：To improve the contrast and preserve more image details in the fusion of infrared and visible images,a fusion method for infrared and visible images based on nonsubsampled contourlet transform (NSCT) combined with image edge feature and adaptive pulse coupled neural network (PCNN) is proposed.For the low frequency subband,the fusion is based on edges of images.For the high frequency subbands,the orientation information of each pixel in images is utilized as the linking strength,and a modified spatial frequency is adopted as the input to motivate the adaptive PCNN,and the fire amplitude is employed to determine the coefficients selection.Experimental results indicate the effectiveness of the proposed algorithm.关键词：image fusion;nonsubsampled contourlet transform;pulse coupled neural network;edge feature;spatial frequency;infrared image267|4|15更新时间：2025-07-16
- 摘要： In order to meet diversified communication needs of the people and build a reliable low-cost communication link,we establish a novel display-to-camera communication system using display screen and photographic equipments in daily life.We build the system model and expound the transceiver's implementation framework,then design a colorful 2D code streaming consistent with the display screen properties for carrying information.Employ computer image processing technology to match,recognize and track the signal area,filter the background noise.Utilize frame classification and color enhancement technology to suppress the inter symbol interference.The system's data transfer rate is 287kbit/s and the decoding accuracy rate is 99.8%.关键词：visible light communication;display-to-camera communication;system design;image processing353|3|1更新时间：2025-07-16
- 摘要：Dual-polarized antennas have aroused much attention in wireless communication systems due to the excellent performance of polarization diversity.Therefore,a broadband dual-polarized microstrip slot antenna with high port isolation is proposed.Two feeder lines of different structures are employed to excite the horizontal and vertical polarization modes and obtain high port isolation.Furthermore,the broadband and miniaturization characteristics of the antenna are achieved by etching slots on the ground plane.The simulation results indicate that the bandwidth of port 1 and port 2 are 51% and 62% respectively,and the port isolation is higher than 40 dB from 1.71GHz to 2.69GHz.It has a simple structure and is suitable for practical applications of mobile communications.关键词：dual-polarized;high port isolation;broadband;slot antenna413|2|5更新时间：2025-07-16
- 摘要：In this paper,a new greedy refinement bayesian approach (GRBA),used to solve the joint sparse signal recovery problem,is proposed.The joint sparse property of signals is first used to model the signals.Based on the model,a greedy Bayesian inference method used to estimate the signals is then presented.In order to enhance the performance of the recovery,the covariance matrix got by the Bayesian inference is utilized to refine the support recovery results in our inference process.The analytical results show that GRBA outperforms the reported algorithms in the literature in terms of both the signal recovery accuracy and computational complexity.It keeps both the advantages of Bayesian methods and greedy methods.Numerical simulations verify the effectiveness of the analytical results.关键词：joint sparsity;signal recovery;greedy algorithm;greedy refinement Bayesian approach382|2|3更新时间：2025-07-16
- 摘要：A reliability test method based on cyclic frequency features was proposed to evaluate the blind processing results of linear frequency modulation (LFM) signal.The reference signal was constructed depending on the identified modulationtype and the correspondent parameters estimations at first and the correlations between the observed signal and the reference signal were calculated consequently.The reliability for LFM signal processing result was tested by detecting the presence of cyclic frequencies near zero frequency of the correlations.The theoretical error probability of the detection was derived and the case study for the discrete polynomial transform (DPT) method was described in the paper.Simulation results show that the proposed algorithm avoids estimating of signal-to-noise ratio and is superior to the time domain based method under lower signal-to-noise ratios.关键词：blind signal processing;reliability test;cyclic frequency;LFM signal184|2|5更新时间：2025-07-16
- 摘要：Particle flow filter formulated the dynamics from prior samples with posterior samples with particle flow velocity field to perform Bayesian estimation of system state.To address difficulties of particle velocity field computation in present particle flow filter,a novel particle flow filter based on Gaussian assumption was proposed.The analytical solution of velocity field under linear Gaussian condition was derived.The consistency of this analytical solution with Kalman-Bucy filter for continuous system,when discrete dynamic step goes to zero,was proved.The solution was finally extended to obtain the nonlinear Gaussian velocity field expression which can be approximated by using unscented transformation.Several simulations revealed the effectiveness over classic nonlinear Gaussian assumption on accuracy and particle filter on efficiency and stability.关键词：nonlinear filtering;Bayesian estimation;particle flow filter;velocity field;Unscented transformation383|3|2更新时间：2025-07-16
- 摘要：Based on the correlation between subband coefficients of nonsubsampled contourlet transform(NSCT),a general-purpose no-reference image quality assessment(NR-IQA)method is proposed.Firstly,the correlation between NSCT subband coefficients was analyzed using mutual information and the subband coefficients with strong correlation were determined.Secondly,the structure comparison operator of those subband coefficients were calculated respectively and used to describe the statistics characteristic of image structure information.Moreover,a no-reference image quality assessment model and an image distortion type recognition model were constructed by combining the statistical features of the mean subtracted contrast normalized(MSCN)coefficients and the structural similarity of NSCT coefficients.Finally,a large number of simulation experiments were carried out in the LIVE image quality evaluation database.The simulation results show that this method is suitable for many common image distortion types and correlates well with the human judgments of image quality,and the assessment model is competitive with the nowadays' mainstream evaluation method.关键词：no-reference image quality assessment;nonsubsampled contourlet transform;structural similarity;luminance statistics193|4|6更新时间：2025-07-16
- 摘要：As the traditional fourth order partial differential equation(fourth order equation)algorithm causes edge leakage of image,a leakage compensation method is proposed based on edge detection theory.Firstly the noise image is preprocessed by a nonlinear bilateral filter to obtain the better edge preservation image.Based on the feature of the gradient operator on the detection of image edge and the squared two-norm of gradient difference which is between the result image and the preprocessed image,a constraint item is built.Then the constraint item is added to the corresponding energy functional of fourth order equation.Finally,to adaptively adjust the edge preservation constraint item and improve the performance of edge preservation,an adaptive Lagrange multiplier which is based on image local variance is constructed.The experimental results show that the proposed algorithm not only inherits the advantage of traditional fourth order equation,but also enhances its ability of edge preservation.关键词：fourth order partial differential equation;edge leakage;edge detection;edge preservation constraint324|2|1更新时间：2025-07-16
- 摘要：Due to the changes of target and background during tracking,traditional single classifier tracking algorithms learn a lot of non-target information which result in the decrease of tracking accuracy.In this paper,we propose to use tree structure to save former classifiers as a set.In each frame,a subset of classifiers are chosen according to the path in the tree to classify test samples.We propose a classification algorithm based on cluster similarity comparison.A normalized feature space is established according to the variance of the cluster.The target in a new frame could be got by computing the distance between test samples and the center of the cluster.Experiments show that our algorithm could achieve the goal of robust tracking under complicated conditions.关键词：object tracking;multiple classifiers;online learning;Haar-like feature289|3|4更新时间：2025-07-16
- 摘要：There are many problems on low observable target tracking based on radar in the presence of multi-range-false-target jamming such as lots of false target tracks,the difficulty in multi-range-false-target discrimination,the unstability of target tracking and so on.In this paper a new method of discriminating real-false-target based on the statistical characteristic of angle measurements and the low observable target tracking technique based on the equivalent measurement are proposed.The false target measurements are eliminated mostly and the low observable target tracking is more stable.Simulation results verify the validity of the proposed algorithm.关键词：statistical characteristic;multi-range-false-target jamming;low observable target;target tracking222|2|10更新时间：2025-07-16
- 摘要：The traditional subspaces based visual trackers well solved appearance changes and occlusions.However,they were weakly robust for complex background and prone to model drifting.To deal with these two problems,this paper enlarges reconstruction errors of the background samples and uses L1-norm loss function to establish an online robust discrimination dictionary learning model.Then an online robust discrimination dictionary learning algorithm for template updating in visual tracking is designed via the block coordinate descent (BCD).Finally,robust visual tracking is achieved with the proposed template updating method in particle filter framework.The experimental results show that the proposed method has better performance in robustness and accuracy than the state-of-the-art trackers such as IVT(Incremental Visual Tracking),L1APG(L1-tracker using Accelerated Proximal Gradient),ONNDL(Online Non-Negative Dictionary Learning) and PCOM(Probability Continuous Outlier Model).关键词：visual tracking;template updating;dictionary learning;particle filter362|2|4更新时间：2025-07-16
- 摘要：To improve the tracking accuracy of hypersonic target in near-space,the effect of target hypersonic movement on radar detection and tracking is analyzed,and a hypersonic target tracking algorithm is proposed based on radial velocity compensation and cancellation processing of conjoint measurements under the ECEF coordinate.Firstly,based on the analysis of effect of target hypersonic movement,measurement model is constructed to reduce the filter divergence which is caused by model mismatch.Then,the high dynamic biases due to the target hypersonic movement are approximately compensated through radial velocity estimation with ambiguity solution,to achieve the target tracking with low systematic biases in near space.Finally,the measurement equation of single radar is constructed to further achieve the robust tracking of the near-space hypersonic target,and the track association problem with lower systematic biases can be avoided at the same time.Simulation results show that near-space target tracking can be finished more effectively than existing methods by using the proposed algorithm.关键词：near space;hypersonic;high dynamic biases;maneuvering target;tracking293|2|3更新时间：2025-07-16
- 摘要：The paper investigates the target tracking problem arising in FM signal based passive multi-static radar,and proposes an integrated track management method.We divide the tracks into four statuses,i.e.initial track,tentative track,confirmed track,and deleted track.Tracking methods for each kind of tracks are detailed.We sequentially exploit measurements of each receiver-transmitter pair to update the tracks,causing the rapid reduction of the computation complexity.Simulation and the real life data results demonstrate the effectiveness of the proposed method.关键词：passive multi-static radar;FM signal;target tracking;track management195|2|1更新时间：2025-07-16
- 摘要：Using the sparse property of the signal from a marine micromotion target,the extraction and detection of micromotion signatures in sparse domain are studied.An algorithm for sea clutter suppression and micromotion target detection is proposed based on the morphological component analysis (MCA).The algorithm takes full advantage of the morphological differences between sea clutter and micro-Doppler signal,and can separate them via sparse representation of different source signals using different dictionaries.Moreover,the proposed sea clutter suppression method in sparse domain can achieve both target's energy accumulation and sea clutter suppression with improved signal-to-clutter ratio (SCR).Simulated and real data all verify the effectiveness of the proposed method.关键词：radar target detection;sea clutter;micro-Doppler;sparse representation;morphological component analysis (MCA)416|2|20更新时间：2025-07-16
- 摘要：A relevance feedback algorithm based on RankBoost for content-based motion data retrieval (CBMR) is presented and has two characteristics.First,KNN-DTW is employed as the weak ranker for RankBoost ensemble learning.While adapting to variable-length multivariate time series (VLMTS) data,by taking the advantage of the ensemble and efficiency of RankBoost,it can resolve the conflict between the real-time requirement of relevance feedback and the high computational complexity of VLMTS data.Second,minimizing ranking experience loss and generalization loss risk proposed in this paper are used as the learning objective for RankBoost ensemble learning,which can effectively solve the over-fitting problem caused by small-sample training in relevance feedback.Experimental results on CMU action library verify the effectiveness of the proposed algorithm.关键词：motion capture data;relevance feedback;RankBoost;rank loss261|2|1更新时间：2025-07-16
- 摘要：To solve the problem of the curse of dimensionality of gene expression data due to the characteristic of high dimension low sample size,a new method of dimensionality reduction for gene expression data,called sparse class preserving projection (SCPP) is proposed,by combining regression and class preserving projection(CPP).Compared to CPP,SCPP can avoid the problems of matrix singularity and over-fitting.Experiments are performed on gene expression data for visualization and sample classification,and the results confirm the effectiveness of the method.关键词：gene expression data;high dimension and low sample size;class preserving projection;regression392|2|1更新时间：2025-07-16
- 摘要：To solve the contradiction of image denoising and detail-preserving under high-density salt-and-pepper noise,this paper proposes a Neutrosophy-Gray filter by using the fusion of indeterminacy information.It has a two-stage scheme:noise detecting and noise removing.In detecting stage,to improve the accuracy of noise detection,Max-Min algorithm is employed firstly,then noise candidates are judged again by the dual criteria of Extreme-Compression-Grey-Correlation-Degree (ECGCD) and Ordered-Indeterminacy (OI).In filtering stage,the algorithm applies the multiplicative fusion of ECGCD and indeterminacy to measure the similarity of pixels,and a Neutrosophy-Gray adaptive weighted function is presented.Experiments show,for different images,the rates of noise eliminating change between 0.1% and 8.8%,and performances of denoising and detail-preserving of the proposed algorithm are superior to current filters even at high level noise (70%~90%).关键词：salt-and-pepper noise with high-density;double noise detection;neutrosophy-gray adaptive weight;extreme-compression-grey-correlation-degree;ordered-indeterminacy;neutrosophy288|2|2更新时间：2025-07-16
- 摘要：Contradiction between the global QoS requirements and local service QoS status monitor decreases the availability of composite service,and makes it hard to meet users' requirements.Aiming at this problem,a framework for composite service adaption is proposed.And the mechanism for composite services QoS decomposing and individual service status monitor in this framework is demonstrated.To get the threshold of individual service,an approach to predict the service QoS by analyzing the historical QoS is studied.Further,to decrease the overhead of composite service adaption,the relax index is introduced into the mechanism.The experimental results show that predicting the QoS threshold and relax index can make the composite service QoS decomposing more reasonable,and can satisfy the user's end-to-end requirement through little adjustment to the greatest extent when changes happen.关键词：QoS;global constraint;QoS decomposing;relax index163|2|3更新时间：2025-07-16
- 摘要：Enabled to provide pervasive access to distributed resources in parallel ways,heterogeneous scheduling is extensively applied in large-scaled computing system for high performance.Conventional real-time scheduling algorithms,however,disregard energy-efficiency in addition to stringent timing constraints.In recognition of green computing,an energy-aware model is firstly presented.Secondly,inspired by multi disciplines,the meta-heuristic is addressed based on the supercomputer hybrid architecture.On the other hand,some technological breakthroughs are achieved,including boundary conditions for different heterogeneous computing and grid scheduling and descriptions of real-time variation of scheduling indexes (stringent timing constraints and energy-efficiency).Extensive simulator and simulation experiments highlight higher efficacy and better scalability for the proposed approaches compared with the other three meta-heuristics;the overall improvements achieve 8%,15% and 17% for high-dimension instances,respectively.关键词：heterogeneous scheduling;green computing;co-evolution;hierarchical parallelization411|2|1更新时间：2025-07-16
- 摘要：Mining opinion leaders in social network is important for analysis of information dissemination and evolution of public opinion.This paper conducts the study on this problem considering structural features,behavior and emotional characteristics comprehensively.Firstly,we extract topics from micro-blogging texts,and get user communities according to the topic division,and an interactive network topology of topic community is built with the following relationships.Then,three kinds of user feature are gained from different aspect:network structure,user behavior and user sentiment.Finally,according to the analysis of users' influence distribution,opinion leaders mining algorithm MFP (Multi-Feature PageRank) is proposed.Experiments show that the algorithm can obtain the potential opinion leader nodes effectively,and have a good performance in support rate from other user nodes.关键词：social network;topic;sentiment analysis;opinion leader264|2|15更新时间：2025-07-16
- 摘要：The locality sensitive hashing (LSH) and its variants are efficient algorithms to solve the k nearest neighbor (kNN) search problems on high-dimensional data.However,with the increase of large data size,the traditional centralized LSH algorithms cannot meet the challenge of the big data era.Based on a new AND-OR construction,this paper proposes an algorithm (called C2SLSH) for the k nearest neighbor search on big data.Different to the traditional algorithms,the C2SLSH can directly get the results from an index without having to compare the original data.The theoretical analysis and experimental results show that the algorithm has stable scalability on a distributed platform.Furthermore,it is faster than the conventional methods for about three times with the same accuracy rate.关键词：kNN;LSH;MapReduce;collision counting sorting586|2|2更新时间：2025-07-16
- 摘要：In multi-domain software defined networks,the existed switch migration strategies always have big computation space and only consider single migration factor.Once the controller gets broken,the switches cannot be migrated immediately.This paper presents the controller hot backup and election problem and designs the corresponding algorithms to find the backup space and complete the master controller election.To reasonably build the network,this paper considers the message exchange cost,the disconnectivity cost,load imbalance cost and cross domain cost.Results show that,compared with the existed algorithms,the proposed algorithms reduce the controller backup space by an average of 65%,and increase the weighted comprehensive evaluation up to 71% in OS3E topology.关键词：software defined networks;multi-controller;hot backup;controller election;failover397|2|5更新时间：2025-07-16
- 摘要：As a new type of on-chip interconnection architecture,network-on-chip overcomes the bottleneck problem of the system-on-chip during the development.However,a failure arising in a router or a link between routers in network-on-chip will cause the reduction of network performance.To avoid this phenomenon,this paper puts forward a fault-tolerant routing algorithm aiming at a path fault and local congestion in network-on-chip.Firstly,the algorithm designs a fault model that reflects the fault status of the path within two hops.As a result,this novel fault model makes the router achieve a dynamic perception of path state within two hops with less cost.Secondly,a novel congestion model has been proposed for reflecting the state of the local network more accurately,contributing to balance network traffic.Finally,when a fault occurs,the algorithm not only is fault-tolerant but also makes sure the network has a good performance.What's more,the algorithm chooses the optimal path under the condition of fault-free.Experimental results show that the proposed algorithm has 10%~20% lower latency in average and 25% higher throughput rate than the contrast case when the network is fault-free.In the case of defective in the network,the advantage of the present scheme has a bigger superiority.关键词：network-on-chip;fault model;congestion model;fault-tolerant routing algorithm3|2|4更新时间：2025-07-16
- 摘要：In this paper,a method to determine similarity and the basic belief assignment (BBA) generation based on bell function (Bell-F) is proposed in order to solve the problem that the fuzzy similarity used in BBA of evidence theory exist paradox when the cognitive objective is a single point.This method can avoid the paradox which is inconsistent with the actual result in common sense,and can more granularly describe similarity evaluation model to improve the accuracy of cognitive description further.The results of a recognition experiment performed for data set of Iris,demonstrate the effectiveness of this method.Furthermore,this method still has good adaptability in uncertain environment when the number of known samples is insufficient.关键词：evidence theory;basic belief assignment;bell function;similarity evaluation model;cognitive description2|2|1更新时间：2025-07-16
- 摘要：Designed a new integer-order and three-dimensional cellular neural networks system.Through nonlinear dynamics analysis,numerical calculation and circuit simulation,the existence of chaotic attractor and realizability in physical about the system were verified.At the same time,studied the system's chaotic characteristics under the conditions of different combination about fractional order qi(i=1,2,3),by adjusting the linear parameter b.According to the theoretical analysis of each unit circuit of fractional-order circuit,designed a corresponding fractional order cellular neural networks system,which has variable parameter b and switchable qi.Statically,the design can realize 13824 kinds of multiple combination circuits.This paper selects several representative combinational circuits for circuit simulation.The simulation results show that multiple circuit simulation and numerical simulation have similar chaos phase diagram,which confirmed the system still has rich dynamic characteristics under the condition of the fractional-order,also has flexible application value and realistic significance.关键词：cellular neural networks;fractional-order circuit;chaotic attractor;circuit simulation;switchable circuit4|2|0更新时间：2025-07-16
- 摘要：A pre-failure feature extraction and modes classification method of board-level package subjected to vibration loading is presented for prognostics and health management of electronics using adaptive spectrum kurtosis and kernel probability distance clustering.Firstly strain response data of electronic components is filtered by empirical mode decomposition method based on maximum spectrum kurtosis,and fault symptom vector is developed by computing and reconstructing the envelope spectrum which contains potential fault information.Secondly nonlinear fault symptom data is mapped and clustered in sparse Hilbert space based on Gaussian radical basis kernel probability distance method.Several cluster centers are formed with the characterizations of the board-level package health state and various failure modes.Finally the current state of board-level package is estimated on basis of its envelope spectrum by computing its probability distance,and the forthcoming failure mode is identified before it happen.The experimental analysis demonstrate the method can recognize and predict the upcoming failure mode of board-level package effectively and serve as a new approach to achieve PHM of electronics.关键词：board-level package;prognostics and health management (PHM);spectrum kurtosis;kernel probability distance clustering;vibration loading3|2|3更新时间：2025-07-16
- 摘要：The domain structure in the existing QSM (quotient space model) is usually a topology,and a granule is uniquely determined by an equivalence relation.However,when the domain structure is assumed as a widely used algebra instead of a topology,it introduces the concept of congruence relation,and systematically demonstrates the existence of two basic conclusions in QSM based on algebraic structure—all the congruence relations forming a complete semi-order lattice and the principles of falsity preserving and truth preserving.And when the equivalence relation determining a granule is not a congruence relation,it defines the concepts of least upper (greatest lower) congruence and least upper (greatest lower) quotient in antithesis,proves their existence for simplicity,and discusses some of their important properties which are the theoretical basis for the composition and decomposition of different granularities.Finally,based on the routing algorithm transmitting as error correcting codes,it analyzes the application of QSM based on algebraic structure during network secure transmission.The paper extends the theory of QSM from structure,and provides theoretical basis for the combination of quotient space theory and algebraic theory.关键词：granular computing;quotient space;congruence closure;quotient operation;least upper (greatest lower) quotient2|2|5更新时间：2025-07-16
- 摘要：Since the family of Schweizer-Sklar t-norm is flexible,they have good characteristics for fuzzy reasoning based on these flexible operators.In this paper,the properties of the Schweizer-Sklar operators family and the robustness of fuzzy reasoning algorithms are studied.The family of Schweizer-Sklar t-norms are decreasing for the variable m.The family of Schweizer-Sklar t-conorms are increasing for the variable m.These perturbations of Schweizer-Sklar t-conorms,Schweizer-Sklar t-norms and its residual implications are given.We proved that Schweizer-Sklar residual implication operators (include Lukasiewizc implication operator) are more suitable in fuzzy reasoning for m∈(0,∞).Moreover,we showed that the FMP reverse triple I algorithms based on the Schweizer-Sklar residual implications are robust for m∈(0,∞),and the FMT reverse triple I algorithms based on the Schweizer-Sklar residual implications are robust for m∈(0,∞).关键词：Schweizer-Sklar t-norms;reverse triple I algorithms;Minkowski distance;robustness2|2|1更新时间：2025-07-16
- 摘要：Traditional grid point-based area coverage methods are committed to algorithm optimization,causing coarse approximation and high complexity problems.In order to solve these problems,based on the probabilistic sensing model,we first study the sensing probabilities of two adjacent points and obtain the fundamental mathematical relationship between them.According to this relationship,we define the concept of feature point set (FPS) to character the area.Then,we transform the probabilistic area coverage into optimization problem of FPS.Further,we design an improved particle swarm optimization (IWPSO) algorithm to solve this optimization problem,which can effectively avoid the premature problems in the convergence of PSO algorithm.Finally,through extensive simulations,we demonstrate that our algorithm outperforms the proposed solutions significantly,and provides a new train of thought for area coverage problem.关键词：Wireless sensor networks;coverage optimization problem;probabilistic sensing model;feature point set;inertia weight;parallel local particle swarm optimization2|4|15更新时间：2025-07-16
- 摘要：The terahertz backward wave oscillator (THz-BWO) is a THz radiation source with the virtue of high power,tunable broad bandwidth and continuous wave operating at normal temperature.The applications of terahertz backward wave oscillator and its development in THz technology were presented in this paper.It shows that the THz-BWO plays important roles and has bright future in THz research.The state of the art and difficulties of THz-BWO were summarized.It could be a reference for THz-BWO study.关键词：backward wave oscillator;terahertz2|2|2更新时间：2025-07-16
- 摘要：This paper proposed a method to generate precoding,which is applicable to the TD-LTE system.This method contains three parts:channel state information (CSI) model,energy distribute model,and beam-forming model.This scheme fully uses the character of exchanging channel for the TDD system,which can obtain the CSI of the downlink channel,and enhances the performance of anti-interference by using the precoding based on the non-codebook.Furthermore,it can enlarge the range of the serving cell.The background of this paper is LTE downlink system equipped with these spatial-correlated receive antennas,where a transmitted precoding method is designed for Rice channel with LOS.This method can keep the precoding algorithm based on non-codebook at a quick convergence speed with low calculation complexity.关键词：precoding;LTE;correlated rice channel;non-codebook2|3|1更新时间：2025-07-16
- 摘要：The traditional rigid routing mechanism has been unable to meet the various service demands and the deployment of new network architectures in future.Aimed at this problem,this paper proposes the polymorphic routing model which is based on the adaptation between routing function and service requirements,and implements the polymorphic routing prototype.The prototype supports the coexistence and customization of a variety of routing protocols in both homogeneous and heterogeneous networks through the virtualization technology and the selective data plane for query and forwarding.Finally,the prototype was implemented based on the NetFPGA-10G platform.Compared with the existing routing systems,the polymorphic routing system realizes the coexistence and customization of various routing protocols,and achieves higher forwarding rate,better scalability and insurance of the quality of service at the same time.关键词：routing;polymorphic;virtualization technology;dataplane;NetFPGA3|2|0更新时间：2025-07-16
- 摘要：A new PSO algorithm is proposed in this paper for feature selection.Distances within the same class and between different classes are used as the index for distinguishing different classes,and thus can be used to construct the fitness function of particles in PSO.The direction of particles for searching optimal features which can result in close intra-class distance and far inter-class distance is determined by the current best solution of the particle and the optimal individual in particle neighborhood,weighted by the fitness function.Meanwhile,the PSO algorithm is aggregated by the weighted voting method to improve its stability and robustness.The experiment results on 5 high dimensional datasets show that the ensemble PSO algorithm is effective and feasible.关键词：feature selection;PSO(particle swarm optimization);ensemble method;classification2|2|4更新时间：2025-07-16
- 摘要：The moving electrode micro-gap is a core part of short-circuit spark discharge system of safety spark test apparatus (STA) specified by the international electrotechnical commission (IEC),it is the key difficulty of researching on IEC-STA short circuit discharge mechanism and characteristic.In order to establish the mathematical models of capacitive circuit short-circuit discharge on the IEC-STA,its electrodes are scanned with scanning electron microscope (SEM).A physical model of the electrodes micro surface in the most dangerous case is established.Mathematical models of IEC-STA cathode surface electric field are established by improved charge simulation method (CSM),the parameters setting,algorithm technological process and the method for ill-conditioned matrix are presented.The numerical computation for IEC-STA cathode surface electric field in different micro-protrude density being developed with CSM shows that there is one density which makes the electric field enhancement factor be the highest.The cathode surface electric field in different electrode-spacing being calculated with CSM shows that the enhancement factor decreases with the reduced electrode-spacing when the electrode-spacing is longer,while it increases with the reduced electrode-spacing when it is shorter.The results will prepare for the further research on the short-circuit discharge with IEC-STA.关键词：micro-gap;IEC safety spark test apparatus;short-circuit discharge;charge simulation method;electric field enhancement factor3|3|4更新时间：2025-07-16
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