最新刊期
卷 44 ， 期 1 ， 2016
- 摘要：In view of the nonlinear and non-stationary sea clutter signal, we put forward a de-noising method of sea clutter based on ensemble empirical mode decomposition(EEMD).By EEMD, sea clutter data containing the target signal can be decomposed into a series of intrinsic mode function.Noise component uses the Savitzky Golay filter method for de-noising.The mode components after filtering and the remaining components are reconstructed into a new signal.Combined with least square support vector machine, single-step prediction model of chaotic sequence is set up.Compare the root mean square error before and after de-noising so that we can evaluate the denoising effect from the root mean square error.The experimental results show that EEMD algorithm is effective for the de-noising of the sea clutter.By de-noising, the root mean square error can be reduced by one orders of magnitude, reaching 0.0028, while the model before de-noising can reach only 0.0119.关键词：the sea clutter;ensemble empirical mode decomposition;autocorrelation function;Savitzky Golay filter360|1668|11更新时间：2025-07-16
- 摘要：An image forensic method based on coefficient-pair histogram of differential DCT coefficient was proposed.In the method, the image is firstly transformed by DCT, and then the differential DCT coefficient of four directions, such as horizontal direction, vertical direction, diagonal direction and the second diagonal direction are computed.After that, the coefficient-pair histogram for each differential DCT coefficient is calculated.Finally, support vector machine (SVM) is used to classify the authentic and spliced image through training the feature vectors of authentic and that of tampered image.The experimental results show that the proposed approach not only has low computing complexity, but also outperforms all the state-of-the-art methods in detection rate on the same test database.关键词：image forensics;differential DCT coefficient;coefficient-pair histogram;support vector machine249|2183|0更新时间：2025-07-16
- 摘要：This paper investigates provably secure position-based key exchange protocols between two provers.To begin with, this paper presents the notions of the prover-to-verifier mode and the prover-to-prover mode, which is the first to distinguish between the two modes for position-based key exchange.At the same time, this paper formalizes the definition of secure prover-to-prover position-based key exchange.Then, a provably secure prover-to-prover position-based key exchange protocol P2PKE1 in 1-dimension is proposed in this paper.Based on the above protocol, a generic prover-to-prover position-based key exchange protocol P2PKEd in d-dimensions is constructed(1≤d≤3).In addition, this paper extends the proposed protocol and proposes protocol P2PKEd-c with key confirmation and protocol P2PKEd-e without key escrow in d-dimensions.Finally, we discuss the proposed protocols in 3-dimensions from both security and performance perspectives.关键词：prover-to-prover;position-based key exchange;bounded retrieval model;provable security293|829|0更新时间：2025-07-16
- 摘要：Conventional location algorithms are based on the assumption that the sensor locations are exactly known.However, in practical situations, the sensor positions generally include random errors, which can considerably reduce the source localization accuracy.To tackle this problem, a multidimensional scaling analysis based time difference of arrival (TDOA) localization algorithm with sensor location errors is proposed.The proposed algorithm firstly constructs a symmetric matrix using the true sensor locations and TDOAs.Then a set of pseudo-linear equations with respect to the source position is formulated from the subspace theory.Finally, a weighting matrix is designed to mitigate the influence of the sensor location errors on the localization accuracy.The estimation bias and covariance matrix are derived by using first-order perturbation analysis.Simulation study validates the efficiency of the proposed algorithm.关键词：passive location;time difference of arrival;sensor location errors;multidimensional scaling analysis;weighted least squares estimates215|1069|7更新时间：2025-07-16
- 摘要：Due to the problem of error data packets in erasure channel, line block code message propagation(LBCMP)iteration error correction scheme is proposed.This scheme is a combination of linear block code and LT codes.By taking Luby Transform(LT)encoding packets as the redundant correcting packets, it makes use of the correct symbol of linear block code to recover all error packets with elimination method.Our analysis and experiments show that LBCMP iteration error correction scheme reduces the encoding packets of the source for recovering all errors.关键词：message propagation(MP)iterative decoding;fountain code;robust soliton distribution(RSD);line block code(LBC)359|1089|0更新时间：2025-07-16
- 摘要：A sub-matrix three-dimensional mapping method was proposed to improve the matrix transpose efficiency for SAR imaging processing.This method, which is based on storage medium consisting of several banks and uses its data access features, maps two-dimensional data matrix to three-dimensional space of storage medium.The mapping is implemented through sub-matrix and cross bank first data access, and it can give full play to data access efficiency of storage medium.The experimental results show that this method enables the data access efficiency of both dimensional to be closed to sequential access efficiency.It greatly improved the matrix transpose efficiency for SAR imaging processing.关键词：SAR imaging;matrix transpose;cross row access;three-dimensional mapping183|924|0更新时间：2025-07-16
- 摘要：Traditional statistically-based UWB SAR image change detection is usually limited by large pixel value change between multi-temporal UWB SAR images in foliage-concealed targets detection.In order to deal with this problem, a new UWB SAR foliage target change detection algorithm based on bottom-up visual attention is brought up.In the algorithm, multi-scale image features are combined into a single visual saliency map by using the model of visual attention.Then the image local neighborhood information and spatial correlation are used to improve the performance of detection.Finally, the experimental results show that the algorithm can detect the foliage-concealed targets between multi-temporal UWB SAR images with less time and it is robust to registration error.关键词：ultra wide bandwidth synthetic aperture radar (UWB SAR);foliage-concealed targets detection;change detection;visual attention312|1249|3更新时间：2025-07-16
- 摘要：A multiple false targets method based on interrupted-sampling and nonuniform periodic repeater jamming (ISNPRJ) and against to the linear frequency modulation (LFM) pulsed radar with mean level (ML) CFAR detector is proposed.Firstly, the principle is illuminated which takes advantage of the interrupted sampling and repeater jamming (ISRJ) to realize the distribution of multiple false targets.After that several key parameters both the number and the SNR of the false targets are derived.Then jamming effectiveness of the ISNPRJ is analyzed on the basis of the mathematics principle of the interrupted-sampling and periodic repeater jamming (ISPRJ), meanwhile, numerical value of the sampling interval, the sampling pulse width, transmitted pulse width and the transmitted power are calculated.Simulation results show that ISNPRJ can reduce the detection probability of target greatly and jam the radar's detector effectively.关键词：interrupted-sampling;repeater jamming;constant false alarm ratio;multiple false targets;suppress jamming280|2135|30更新时间：2025-07-16
- 摘要：Aimed to a type of networked control system with time-varying delay, it divided the time area into m sections unevenly.Then, it made each different Lyapunov-Krasovskii functional by taking triple integral and combined with free-weighting matrices, used less conservative integral inequality to tackle the derivative of Lyapunov-Krasovskii functional.Furthermore, it got a new stability condition for time-varying delay of networked control system.Finally, numerical example was given to prove the result in this paper.关键词：time-varying delay;networked control system;Lyapunov-Krasovskii functional;stability210|857|5更新时间：2025-07-16
- 摘要：Neural networks are often linearized to construct a framework of neural predictive control, but a challenging issue remains that lots of dynamics caused by omitting high-order terms are unmodeled.We took ESNs (Echo State Networks) as a paradigm, and proposed a ridge regression method to compensate unmodeled dynamics.The unmodeled dynamics were observed by collecting the difference of ESN internal states before-and-after linearization, and they were represented by a linear function of ESN states estimated with ridge regressions.The compensation terms for the unmodeled dynamics were then internalized as movements and rotations of attractors in ESN reservoirs.The internalization provided a new possibility:The loss of boundary constraint because of linearization of activation functions can be partially remedied by the attraction effect of attractors.Two examples demonstrated that our compensation method could actively improve the control.关键词：echo state networks;ridge regression;unmodeled dynamics;predictive control;internalize285|1320|2更新时间：2025-07-16
- 摘要：In MOEAs based on user-preference, reference point is most commonly used to express the preference information, but the position of reference point has detrimental effect on the performance of algorithms.According to this issue, this paper proposes MOEA/D-PRE that combines MOEA/D with preference information and alternate weight method.This algorithm applies the alternate weight method to map the region of interest of the decision maker, which can avoid the influence of the reference point, and the model is easy for the decision maker to adjust the size of preference region.Experimental results show that this approach has much better performance.Moreover, this paper proposes different models to satisfy different demands of the decision maker, which has provided a new way to solve MOPs based on preference information and especially to tackle the effect of reference point.关键词：MOEA/D (multi-objective evolutionary algorithm based on decomposition);evolution algorithm;preference;alternate weight;decision maker179|1414|8更新时间：2025-07-16
- 摘要：Aimed at fuzzy Petri nets (FPN) existing membership single issue, intuitionistic fuzzy Petri nets (IFPN) was constructed for knowledge representation and reasoning by combining intuitionistic fuzzy sets theory and Petri net theory.Firstly, IFPN model was constructed for knowledge representation, and the issue of negative proposition representation was solved by introducing inhibitive transfer arcs into the model.Secondly, the algorithm based on matrix operation was presented, the issue of fact reservation in reasoning procedure was solved by modifying token value's transfer rules after transitions being fired, and the issue of transitions repeatedly being fired was inhibited by modifying firing rules of transitions.Lastly, the algorithm was analyzed, and the feasibility of proposed IFPN model and algorithm was proved through an example.The result indicates that IFPN is an effective extension and development of FPN, and it describes the reasoning result more delicately and comprehensively.关键词：intuitionistic fuzzy Petri nets (IFPN);intuitionistic fuzzy production rules;knowledge representation;intuitionistic fuzzy reasoning197|966|7更新时间：2025-07-16
- 摘要：Multi-objective cellular genetic algorithm has proven to be effective in solving bi-objective MOPs.However, preliminary experiments have revealed that it has difficulties when dealing with three-objective MOPs(the DTLZ problem family).In order to enhance the performance, the orthogonal design idea is introduced and a new cellular genetic algorithm called cellular genetic algorithm for multi-objective optimization based on orthogonal design is proposed.In the progress of iteration of improved algorithm, the parent individuals are divided into many segments, and then several offsprings are produced by recombining the segments according to the orthogonal table, finally, choose the individuals which have better fitness value from the offsprings to the next population.The experiments show that the performance is improved after introducing the orthogonal design.Compared with several state-of-the-art multi-objective metaheuristics, the obtained results show that the improved algorithm is competitive for DTLZ problem family, too.关键词：multi-objective;cellular genetic algorithm;orthogonal design;function optimization2|1145|5更新时间：2025-07-16
- 摘要：A radial basis function(RBF) Galerkin solution based feedback particle filter is proposed to resolve the divergency problem existing in present particle filter when the continuity of system model is violated. A weak formulation of the PDE regarding to the potential of feedback gain is firstly derived, then the RBFs are employed to approximate the potential function. Finally the feedback gain solution is obtained using Galerkin method and Monte Carlo integral, also the method for choosing RBF parameters is provided and analyzed numerically. It is demonstrated that the present FPF diverges under low system sample rate, whereas our proposed feedback particle filter is nevertheless effective, with preferable tracking accuracy and stability under low system sample rate.关键词：nonlinear filtering;Bayesian filtering;feedback particle filer(FPF);Galerkin method;radial basis functions(RBF)192|986|0更新时间：2025-07-16
- 摘要：The mission planning problem of a team of modular and reconfigurable robots (MRRs) in hospital service is studied.By analyzing and modeling, it is abstracted as a multidimensional combinatorial optimization problem with multiobjectives and multiconstraints.A population-based metaheuristic, the Improved Binary Bees Algorithm (IBBA), is proposed to optimize this NP-hard problem.The IBBA is featured as, 1) Functional partitioning and parallel implementation of global search and local search;2) Integrating the methods of combinatorial schemes' expression and evolution, multiobjectives' handling and constraints' handing into the basic algorithm framework;and 3) Improving local search strategy from the prototype algorithm.Experiments are conducted with respect to a practical example.The IBBA exhibits feasibility, stability and advantages over its prototype algorithm in indices of solution quality, computational efficiency and single-objective optimization.Further, the advantages are interpretable from algorithm mechanisms.This study extends the field of research of MMR, and provides a general modeling method and optimization algorithm to solve general combinatorial optimization problems with multiobjectives and multiconstraints.关键词：modular and reconfigurable robot (MRR);robot team;multidimensional assignment problem (MAP);combinatorial optimization problem (COP);improved binary bee algorithm264|1070|1更新时间：2025-07-16
- 摘要：On account of the characteristics that the data cache will be frequently accessed in a short period of time, this paper proposes a low power data cache access methods based on hotspot initiative search and historical access trace.The method will automatically judge hot process, dynamically buffer the target hotspot location information to filter tag and redundant data memory access.Running EEMBC benchmark results show that compared with MRU prediction method(Most Recently Used) this approach can reduce 30.77% dynamic access power, and get 26.21% performance improvement.关键词：low power;filter access;hotspot initiative search155|1337|0更新时间：2025-07-16
- 摘要：The traditional software defect prediction methods have weak adaptive ability for cross-project defect prediction, largely because of feature distribution differences between the source and target projects.In order to resolve this problem, we propose a novel weighted naive Bayes transfer learning algorithm.Firstly, the feature information of the test data and training data are collected;next, our solution computes feature differences, and transfers cross-project data differences into the weights of the training data;finally, on these weighted data, the defect prediction model is built.Our experiments are conducted on eight open-source projects, and experimental results demonstrate that our method significantly improves cross-project defect prediction performance, compared to other methods.关键词：software defect prediction;transfer learning;machine learning;naive Bayes377|2476|9更新时间：2025-07-16
- 摘要：The deployment optimization of service-oriented software is well known to be NP hard.In this paper, a software deployment optimization model is built for improving the performance of service-oriented software, and an Ant Colony Algorithm for Deployment Optimization (ACO-DO) is designed to solve it so that the near-optimal solutions can be obtained quickly.The algorithm improves ant colony algorithm by designing a heuristic based on the considered problem, optimizing the orders of constructing deployment solutions and adding a local search procedure.A series of instances with different sizes are tested and analyzed.The experimental results show that the designed ACO-DO algorithm performs better than the existing Mixed Integer Linear Programming, ant colony and genetic algorithms.关键词：service-oriented software;deployment optimization;ant colony algorithm;performance287|948|5更新时间：2025-07-16
- 摘要：The degradation behavior for 1.2kV Silicon Carbide (SiC) MOSFET under unclamped repetitive stress (URS) has been firstly investigated in detail by the analysis of two-dimensional device simulations and charge pumping measurements.It has been shown that, when the device is under URS condition, the electric field and impact ionization in the accumulation region become sufficiently large, so as to generate numerous hot holes.These avalanched-generated hot holes will be injected and trapped into the gate oxide above the accumulation region, resulting in an initial decrease of the on-state resistance and threshold voltage, as well as an increase in drain-source leakage current.关键词：silicon carbide;power MOSFET;URS (unclamped repetitive stress);degradation166|946|1更新时间：2025-07-16
- 摘要：Image matching based on contour is an important issue in computer vision, but now there is no mature algorithm that can solve the problems of partial contour matching and deformation caused by non-similar transformation and non-rigid transformation.According to the conclusions that partial contour structure has relative stability and a good description need to merge the contour's local and global information, a local scale description method is proposed which is scale, rotation invariant, deformation tolerant and initial point independence.On this basis, a contour matching algorithm is proposed based on improved DTW.Experimental results show that the proposed method can realize the partial matching between open contour and open contour as well as closed contour.Its matching precision is 92% on average, and improves 30% compared with HD method, improves 26% compared with traditional DTW.关键词：machine vision;contour description;local scale;partial matching;dynamic time warping;deformation371|1108|3更新时间：2025-07-16
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Gaussian Mixture Models and Principal Component Analysis Based Human Trajectory Behavior Recognition
摘要：In order to solve the problems of human motion intention recognition and abnormal behavior detection in home environment, a trajectory analysis based algorithm is discussed in this paper.Firstly, the home environment is divided into different key points and areas, so that the motion trajectory can be described by them.Moreover, based on mixture Gaussian model, the problems of motion intention recognition and abnormal behavior detection are analyzed.Finally, the PCA algorithm is applied to improve the accuracy of abnormal behavior detection.The experimental results show the effectiveness and reliability of the above conclusions.关键词：motion intention recognition;abnormal behavior detection;motion trajectory analysis;Gaussian mixture clustering;principal component analysis2|2068|8更新时间：2025-07-16 - 摘要：Whether the structure coherence and neighborhood consistency can be well maintained directly determines the performance of an inpainting algorithm.To achieve a better inpainting performance, this paper proposes an exemplar based image inpainting algorithm based on direction features extracted by Curvelet transform.Firstly, the super-wavelet transform is applied to extract four direction features of the corrupted image.Then the color and direction information are utilized to measure the similarities between patches.Subsequently, a color-direction structure sparsity function is defined.Afterwards, multiple suitable candidate patches are searched based on the weighted color-direction distance and these candidate patches are applied to sparsely represent target patch under the local neighborhood consistence constraints both in color and direction spaces.Moreover, in searching candidate patches, the error tolerance is adaptively decided according to the feature of target patch.Experiment results show that the proposed method can achieve better inpainted results than the state-of-the-art algorithms, especially when dealing with structure and texture images.关键词：image inpainting;direction feature;weighted color-direction distance;color-distance structure sparsity;Curvelet transform;sparse representation189|1854|3更新时间：2025-07-16
- 摘要：The optimization problem of three dimensional system on chip (SoC) needs to be solved before it enters the market.We propose a reconfigured test architecture optimization of TSV-based (Through Silicon Vias-based) 3D SoC, and the optimization includes both mid-bond testing and post-bond testing.As both test time and the number of TSV for test impact the overall test cost, our proposed scheme can reduce overall test time, while controlling the number of TSVs.Experiment results show that our scheme achieves around 20% on the reduction of test cost compared with one baseline solution which only considers reducing test time.关键词：SoC testing;3D SoC;optimization;test cost224|1108|4更新时间：2025-07-16
- 摘要：In order to solve the problems existing in steganography based on modular function, this paper presents n-dimensional hypercube modulo mapping steganographic algorithm.According to modular arithmetic properties, the algorithm defines an n-dimensional modular function which n pixels values are mapped to a data in an-ary notational system, thus the algorithm realizes that each secret digit in an-ary notational system is carried by n cover pixels.The algorithm can get different rates of embedding and visual quality of stego image when we choose different parameter a, and can get better visual quality of stego image when a is even number and we choose bigger parameter n.Theoretical analysis and experimental results show that the proposed algorithm, by comparing with many steganography, not only has the function of these algorithms, but also has a better visual quality of stego image, better security, and stronger practicability.关键词：digital image;modular function;remainder cycle;steganography182|1010|2更新时间：2025-07-16
- 摘要：Consider the problems of decision-making and recognizing malicious nodes in traditional node reputation security scheme based on light-weighted cloud model, this paper proposes a Modified Light-weighted Cloud Model (MLCM) firstly, and a novel node reputation security scheme is given by then.In order to resolve trust misjudgment, direct and indirect trust values are treated comprehensively before its calculation with simplified backward cloud operator, on the basis of the traditional approach of wireless sensor network trust management on trust value.In addition, cloud membership function is leveraged to obtain recommendation trust value to improve accuracy of recognizing malicious nodes.The experiment shows that the scheme can not only work out the problem of contradiction between the intrusion tolerance and sensitivity but also figure out matter of decision-making and recognizing malicious nodes.关键词：trust value;wireless sensor network security;reputation security;cloud mode276|1268|8更新时间：2025-07-16
- 摘要：What caused channel oscillation among face-to route and face-to client have been analyzed.In order to reduce channel oscillation and promote throughput of channel assignment scheme, evolutionary game has been imported to joint with promoted fruit-flies optimal algorithm, a distributed channel assignment scheme based on ESS-PFOA algorithm has been proposed in wireless mesh network.The simulations reflect that network utility and channel oscillation ratio have been influenced by channel oscillation tolerance factor, and network topology presents homogeneous when β ≤0.5, else it turns to be heterogeneous when β > 0.5 and β ≥0.9.The result reflects that channel oscillation ratio has been fallen from 0.44 to 0.08, channel oscillation inhibition ratio has been restrained, and network utility has been improved in heterogeneous network.关键词：wireless mesh network;multi-radio multi-channel;evolutionary game;channel oscillation;network utility2|1141|1更新时间：2025-07-16
- 摘要：To improve the data transmission efficiency of delay tolerant network (DTN), multiple copies of packets are injected into the network.However, the network will be congested due to large number of redundant copies.To solve the congestion, a congestion control strategy with node status evaluation is introduced in this paper.According to the historical information obtained during the node movement process, the congestion status is determined by combining the direct and indirect estimation results.Furthermore, the relay node can be selected reasonably, and the limited network resources can be utilized effectively.Results show that the packet delivery ratio and network overhead ratio can be improved dramatically by our proposed strategy.关键词：delay tolerant network;network congestion;node status;packet forwarding2|1342|3更新时间：2025-07-16
- 摘要：In view of the energy limits and synchronization requirements of sensor nodes of Internet of Things (IoTs), a low-energy-consumption time synchronization algorithm LECTS is proposed, and the energy consumption's reduction is performed from average synchronization message amount, synchronization period and duty cycle aspects.The network is divided into several parent-child groups and for each group one or more PS nodes are chosen.The intra-group nodes are synchronized continuously and the out-group nodes are synchronized on-demand.In each parent-child group, the parent node and PS nodes exchange synchronous message N times given synchronization period and duty cycle, and other intra-group nodes passively overhear those messages.The clock skew and offset respected to the parent node are estimated jointly based on the maximum likelihood estimation, and thus the intra-group nodes are all synchronized to the parent node.With the given synchronization precision, the network synchronization error is periodically evaluated by the sink node.Synchronization period and duty cycle are adjusted by synchronization controller according to the synchronization precision error.Simulation results show that LECTS method can guarantee synchronization precision and reduce energy consumption effectively, thus it can improve the network's lifetime.关键词：Internet of Things;time synchronization;synchronization energy consumption;synchronization controller3|1527|2更新时间：2025-07-16
- 摘要：Isogeometric analysis (IGA) based on the non-uniform rational B-splines (NURBS) has integrated the advantages of Computer Aided Design (CAD) and the finite element method (FEM).The main feature of IGA is the usage of one common geometry representation for creating CAD models, for meshing, and for numerical simulation.However, IGA based on one single NURBS patch is difficult to deal with the inhomogeneous mediums and complex multiply connected domains because of the limitation of the NURBS patch topology.In this paper, IGA based on the patch splicing is used to solve the waveguide eigenvalue problem of this kind.The control points and meshes of different patches must coincide on the interface, even after refinement.The Helmholtz governing equation can be discreted using the Galerkin procedure.Numerical examples are presented to show that IGA possesses the advantages of better convergence on a per-degree-of-freedom and high accuracy.关键词：waveguide eigenvalue;isogeometric analysis;NURBS;patch splicing;inhomogeneous mediums;multiply connected domains2|1133|1更新时间：2025-07-16
- 摘要：Most of the radio frequency (RF) variable gain amplifiers (VGA) are fabricated in CMOS process and GaAs process.The gain variability is usually realized when the biased voltage/current of transistors is changed or an attenuator in VGAs is built.A RF VGA variable gain amplifier based on high performance RF SiGe heterojunction bipolar transistor(HBT) is presented.The designed VGA consists of a feedback path with a PIN diode.The PIN diode forward resistance is controlled by its forward biased voltage, and hence the dB-linear variable gain is realized when the PIN diode forward biased voltage is altered.After the high-frequency small-signal equivalent circuit of the VGA with the PIN diode feedback is built, the gain controlling mechanism is analyzed.A complete design and implementation of a 1.8GHz VGA with the proposed VGA topology was demonstrated.The test results show that the dynamic gain scope reaches 15dB at the frequency of 1.8GHz when the controlling voltage changes from 0.6V to 3.0V.The noise figure is lower than 5.5dB and the minimum noise figure achieves 2.6dB.The input and output matching keeps well and the linearity is also acceptable in the whole voltage variable range.关键词：variable gain amplifier;PIN diode;small-signal equivalent circuit;SiGe heterojunction bipolar transistor;radio frequency2|1071|0更新时间：2025-07-16
- 摘要：An ultra-low power successive approximation register analog-to-digital converter for biomedical application is proposed.Many ultra-low power design methods are utilized for its main modules.The digital-to-analog converter (DAC) employs a vcm-based and split capacitor array structure to cut down the total capacitance, so as the power consumption.Voltage window technique is used to decrease the power consumption of the comparator without sacrificing its accuracy.Furthermore, stack forcing and multi-Vt design approaches are used to reduce the leakage current under low frequency.The proposed SAR ADC is designed and simulated in 55nm process.With 0.6V power supply and 10kS/s sampling rate, the ADC achieves a signal-to-noise-and-distortion-ratio (SNDR) of 73.3dB.The total power consumption is 432nW and the figure-of-merit (FOM) is 11.4fJ/Conv.关键词：analog-to-digital converter (ADC);successive approximation register (SAR);voltage window;ultra-low power3|1389|1更新时间：2025-07-16
- 摘要：It is of great significance for the grid-connected converter control to extract the grid fundamental positive, negative sequence component and each harmonic component quickly and accurately under non-ideal conditions.In this regard, a positive and negative sequence observer technology is proposed.Based on the modern control theory methods of status observation, the observer is implemented in two-phase stationary reference frame and includes the fundamental and harmonic sub-observer.It can distinguish positive and negative sequence signal with the same angular frequency.It does not require real-time trigonometric functions and is easy to realize.The effectiveness of the proposed observer is demonstrated by the comparative experimental results which show the accurate extraction for the fundamental positive, negative components and harmonic components and good dynamic performance under the unbalance and harmonic interference grid.关键词：grid-connected converter;the positive and negative observer;harmonic extraction;two-phase stationary reference frame2|1276|0更新时间：2025-07-16
- 摘要：Considering the surface effect, the melting temperature and the formation enthalpy of Sn-Ag nanoscale solder alloy were calculated by Miedema model using Lindemann melting criterion.The results show that the melting temperature and the formation enthalpy of Sn-Ag nanoscale solder alloy are dependent on the grain size and component composition.When the particle size is 5nm, the melting temperature decreased by about 7% for Sn3.5Ag nanoscale solder alloy;while the formation enthalpy of the alloy increases with the decrease of particle size, and the alloy stability decreases accordingly.Meanwhile, the formation enthalpy of the Sn3.5Ag solder alloy is completely positive when the grain size is 0.1 μ m, which can create significant influence on the microstructure formation of the Sn-Ag solder alloy.关键词：electronic packaging;Sn-Ag;lead free solder;nanoscale;melting temperature;formation enthalpy2|974|1更新时间：2025-07-16
- 摘要：In this paper, we propose a memory access optimization method to minimize the memory accesses due to weighting factors (cosine coefficients in the computation diagram of fast DCT pruning) and input points for implementing fast DCT pruning on DSP.The proposed method reduces the number of memory accesses in two steps:1.Reduce the number of weighting factors;2.Combine butterflies at two stages in fast DCT pruning diagram to form an efficient butterfly structure in one stage and calculate them.The proposed method is applied to implement Pruning FCT on TI TMSC320C64x DSP.Experimental results show that the proposed method can achieve an average of 40% memory access reduction, 48.6% clock cycle reduction and 32.6% of memory space saving for weighting factors to compute Pruning FCT on DSP comparing with the conventional implementation.关键词：digital signal processor (DSP);discrete Cosine transform (DCT);memory access2|1011|1更新时间：2025-07-16
- 摘要：The Internet with best-effort service for group command transmission produces path competition between commands easily.This paper firstly defines effective path statistics network (EPSN) based on Internet, and defines the group multi-constraints multi-objectives optimization problem based on the EPSN further.Aiming at the problem, this paper puts forward to the model GCTMHA (Group Command Transmission Model based on Heuristic Algorithm).The experiment verifies the reasonableness of the model from transmission success rate.关键词：group command transmission;group multi-constraints multi-objectives optimization problem;heuristic algorithm2|817|0更新时间：2025-07-16
- 摘要：As the group number grows, the classical signature grouping algorithm solves the DFA state explosion problem with a big decrease on matching efficiency.This paper presents a regular expression(Regex) input drive theory.According to such theory, a grouping algorithm based on signature templates, templates based finite automata(TFA), is proposed.TFA divides Regex set based on signature templates and constructs matching engines in each set.Experiment results show that the preprocessing time and storage are reduced by 2~3 orders of magnitude compared with classical DFA improved algorithms, and TFA brings no obvious decrease on matching efficiency.关键词：regular expression;deterministic finite automata;multiple DFAs;extended finite automata;multi-dimensional finite automata;signature templates2|1118|2更新时间：2025-07-16
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