最新刊期
卷 34 ， 期 3 ， 2006
- 摘要：The mathematic model standing for undersampled and nonuniformly sampled signals of MPCSAR is developed and the corresponding imaging result representatives are also deduced in this paper.The reasons of the paired false target echoes are analyzed and the paired echoes are divided into two types,one is called "undersampled type" and anather,"velocity mismatched type".The formulas are given to locate the paired echoes and to calculate the intensity of echoes and the simulation results performed in the paper have proved the validity of those formulas.关键词：multiple phase center SAR;undersamplinhg;velocity mismatch;paired echo0|2|2更新时间：2025-07-02
- 摘要：Traditional Probabilistic Data Association (PDA) algorithm only use the features directly correlative with the target state.A new PDA algorithm based on information fusion of multi-feature of the emitter in passive tracking is proposed.First,the association probability is calculated with gray correlation analysis of multiple features of the target such as the RF,PRI,and PW.Further,the data association is made and the target state is updated based on the information fusion.Compared with the traditional PDA algorithm,the proposed algorithm has two advantages.One is that the calculation of the association probability is faster and more accurate,and the other is that the association performance is much better.Experiments show that the proposed algorithm is superior to the NN algorithm and the traditional PDA algorithm.关键词：passive tracking;gray correlation analysis;Information fusion;PDA0|2|9更新时间：2025-07-02
- 摘要：Down-doped solid core in honeycomb fibers can guide light by PBG effects,and its leakage losses have been analyzed by multipole method.It is confirmed that its leakage loss can be reduced to a level of 10-5 dB/m by only eighty-four air holes,with the hole diameter to pitch ratio of 0.8.These simulations pave the way for the practicality of solid-core PBG fibers.关键词：leakage loss;photonic band gap fibers;solid core0|2|0更新时间：2025-07-02
- 摘要：To obtain the ability of ground moving target indication (GMTI) with acceptable minimal detectable velocity (MDV),the distributed radar carried by a cluster of small satellites is a promising option.However the signal processing is a real challenge due to the difficulties of near field observation,wide band observation and phase coupling which are brought by the three-dimensional sparse distribution of the antennas.This paper studies these difficulties and proposes a new space-time adaptive processing (STAP) method.Using non-simultaneous space-time samples,the new method weakens the difficulties of near field and wide band observation effectively.Then two methods are proposed to improve the applicability for complex terrain.One method splits each receiving aperture into several subarrays and the other adjusts the PRF.Both can improve the signal-to-clutter-and-noise ratio (SCNR) evidently.Simulations show the validity of these methods.关键词：spaceborne radar;sparse array;ground moving target indication (GMTI);space-time adaptive processing (STAP)0|2|5更新时间：2025-07-02
- 摘要：This paper presents a new approach to radar target classification based on one-dimensional scattering centers matching.This approach firstly excludes the spurious scattering centers outside of target region using the range window around target region.Then the scattering centers of two targets are associated in pairs according to their relative ranges.The matching function of two targets is defined by the ratio of the total "matching energy" of all the matched scattering center pairs and the total energy of the two targets’ scattering centers.The performance of the proposed approach is examined through classification experiments.The results show that this approach has good target classification capability,and it is robust to additive Gauss white noise and radar bandwidth.关键词：radar target classification;one-dimensional scattering centers;matching function1|2|8更新时间：2025-07-02
- 摘要：Stream cipher has always been one of the most important encryption methods in cryptography.Now we bring in a stream cipher encryption chip design which is based on neural network algorithm and it not only contains the good statistics of m-sequence but also enhances the periodicity and linear complexity of the output sequences.We use FPGA technology to complete the stream cipher circuit design and the modern electronic design method to smoothly realize operation functions and sequential assignment.The result of logical synthesis simulation verifies the correctness of the chip circuit.This research is helpful to the application of stream cipher algorithm in information security and modern secure communication equipment.关键词：stream cipher;neural network;encryption chip;FPGA0|2|2更新时间：2025-07-02
- 摘要：Layered multicast with receiver driven congestion control is a typical way for media stream distribution.The congestion control protocols in current layered multicast methods lack the limitations to users' behaviors.The receivers may violate the protocol regulations and join upper groups to initiate self-beneficial attacks,which leads to unfair bandwidth usage.This paper presents a general secure layered multicast protocol,SLM.On condition that the routers can assist with congestion control,CR-AC (Congestion state Related Access Control) algorithm based on Shamir's secret sharing scheme is used in edge routers to regulate the users' group subscription behaviors and avoid their self-beneficial attacks.And different users can be confined to different highest subscription levels according to their agreements with service providers.Analysis and simulation results show that SLM can ensure the network flows share the bandwidth safely in real-time,and has preferable scalability features.关键词：layered multicast;congestion control;self-beneficial attack;shamir's secret sharing scheme0|2|0更新时间：2025-07-02
- 摘要：HF (high frequency) adaptive radio communication signal (HF-ARCS) detection is an important research problem in the domain of electronic warfare.A new method based on fourth-order cumulants diagonal slice for the detection of HF-ARCS is presented.The subsection-based estimation method for the fourth-order cumulants diagonal slice of real data is proposed and its asymptotic characteristic is analyzed as well.The asymptotic analysis shows that the estimation method reduces estimation mean square error.The detection principle is introduced and the capability of different detection methods in Gaussian distributed white or colored noise under different signal noise ratio is investigated with the help of computer simulation.The comparing simulation results demonstrate the effectiveness of the new method.关键词：fourth-order cumulants;diagonal slice;signal detection;HF adaptive radio communication signal0|2|5更新时间：2025-07-02
- 摘要：The method of airborne emitter recognition based on multisensor system of ESM and ELINT is deeply discussed in this paper.First,based on the measurement of ESM system,a new method to calculate the Basic Probability Assignment Function (BPAF) with fuzzy synthetic evaluation is proposed.Based on the measurement of ELINT system,the method to calculate the BPAF with the gray correlation analysis is proposed too.And further,the paper introduces the multisensor data fusion method based on the Dempster-Shafer (D-S) evidence theory,which is applied to the airborne emitter recognition of multisensor system of ESM and ELINT.The experiments indicate that the proposed method to calculate BPAF is practicable and the recognition method is effective.关键词：ESM;ELINT;evidence theory;data fusion;emitter recognition0|2|16更新时间：2025-07-02
- 摘要：This paper deals with the method to raise the front to back (F/B) ratio on the pattern for the slots antenna of rectangular waveguide.The EBG (electromagnetic band-gap) high-impedance surface structure is utilized as a high-impedance ground plane for slots on rectangular waveguide to raise the front to back (F/B) ratio,and detailed analysis is made to study the influence of EBG high-impedance surface characteristic on the radiation properties of the slots array antenna of rectangular waveguide by using the simulation method.The electric parameters of the designed example antenna are measured.The experimental results show that this method is effective.关键词：waveguide slot antenna;EBG high-impedance surface structure;patterns;front to back ratio0|2|1更新时间：2025-07-02
- 摘要：Image magnification plays an important role in many fields.An algorithm based on fractal codes and model constraint is proposed in this paper.The fractal codes can carry the spatial information as well as the self-similarities present in the image.First,the image is magnified with multiple range block partition schemes,then their results are averaged to get one magnification image and thus the block artifact is reduced.Finally,the magnification image is modified by a constrained model.Experiments show that the proposed approach performs better than the other fractal based magnification method.关键词：image magnification;fractal coding;model constraint0|2|7更新时间：2025-07-02
- 摘要：Super resolution for target range and azimuth angle of a novel bistatic HF-Surface Wave Radar (HF-SWR) is investigated.As different transmitting antenna utilizes different carrier frequency,there has coupling between target range and azimuth angle.According to the characteristics of the target range and azimuth angle coupling,a method employ the Multiple Signal Classification (MUSIC) algorithm to achieve target range and azimuth angle super resolution is proposed,which can improve range and azimuth angle estimation accuracy under multiple targets environment.Simulation results validate the effectiveness of this method.关键词：HF-SWR (HF-Surface Wave Radar);super resolution;MUSIC (Multiple Signal Classification)0|2|7更新时间：2025-07-02
- 摘要：Direct blind equalization of single-input-single-output (SISO) IIR channel is investigated.Only second-order statistics is required and the channel order need not be known.By oversampling the channel output,we transform the SISO IIR channel into a special Single-Input-Multiple-Output (SIMO) model,in which the subchannels have identical autoregressive (AR) part.A linear prediction approach is applied to the output of this SIMO model and we prove that the prediction error contains the parameters of the first time slot of the model impulse response.These parameters then can be estimated from the covariance matrix of the prediction error.Based on the estimated parameters,zero-forcing equalizers with different delay can be developed.Computer simulation results illustrate the effectiveness of the proposed algorithm.关键词：oversampling;multichannel model;blind Channel equalization0|2|5更新时间：2025-07-02
- 摘要：Recent studies have been shown that multiple-input multiple-output (MIMO) techniques have the potential to drastically increase the data rate of wireless communications with no additional power or bandwidth consumption.In a conventional MIMO system that is refered to as the antenna-channel MIMO system,the outputs from receive antennas are selected directly as the multiple-output signals.The structure of the beam-channel MIMO system is proposed.In a beam-channel MIMO system,the outputs from multiple beams are selected as the multiple-output signals.Based on the directional array response vector,the simulation algorithm on the impulse response matrix of the narrowband MIMO channels is proposed.On the proposed algorithm of the channel impulse response matrix,the analysis algorithms on the capacity limits of the antenna-channel MIMO system and the beam-channel MIMO system are presented.Both theoretical analyses and simulation results indicate that: beam channels can increase signal to noise ratio (SNR),mitigate cross-correlation properties among channels,consequently,the beam-channel MIMO system has a bigger capacity limit than that of the antenna-channel MIMO system.关键词：wireless communications;MIMO systems;beam channels;antenna channels;capacity0|2|1更新时间：2025-07-02
- 摘要：The characteristic of space-time adaptive processing (STAP) algorithms is analyzed,and a parallel computation model for STAP is proposed.Then the real time performance is analyzed and some ways to increase the real time performance are found.The effective ways to reduce latency are reducing the latency of different phase independently or using the output of previous pipeline.And the ways to increase throughput are adding more pipeline or avoiding the bottleneck phase.Based on the model,several kinds of STAP systems have been developed.关键词：space-time adaptive processing (STAP);parallel computation model;parallel processing0|2|2更新时间：2025-07-02
- 摘要：As IPv6 networks rapidly deployed,native IPv6 backbones (such as CNGI) are emerging.However,vast applications and services still stay in IPv4 network.Thus,interconnection of IPv4 networks over IPv6 backbones is required.Unfortunately,there are no suitable transition mechanisms available to satisfy this requirement.We propose a 4over6 framework for IPv4 network interconnection over IPv6 backbone without explicit tunneling.The 4over6 mechanism is discussed and analyzed.Prototype implementation verifies the theory of the framework.ISP independent deployment scheme then is proposed which reduces the routing overhead and increases the practicability of 4over6 deployment.Being transparent to IPv4 and IPv6 networks,the light weight scalable 4over6 framework is fit for large-scale complexity network interconnection with automatic discovery and control.关键词：4over6;IPV6;IPv4;transition;internet0|2|6更新时间：2025-07-02
- 摘要：The existing pattern synthesis method can't be used for superdirective array antennas for they can't ensure the dominance of external noise as well as keep high array directivity .A new pattern synthesis method which can be applied to superdirective arrays is presented .It can also be applied to arbitrary array geometries .The dominance of external noise is ensured by constraining the array efficiency,and the desired sidelobe level is achieved by implementing linear constraints through iteration .By optimizing the array directivity subject to array efficiency and sidelobe constraints,the highest possible directivity with controlled array efficiency and desired sidelobe level is achieved,and the requirement on superdirective array synthesis is satisfied .The simulation results of different arrays show that the proposed method is very effective and flexible.关键词：superdirective array antenna;array synthesis;directivity;array efficiency0|2|3更新时间：2025-07-02
- 摘要：A new adaptive beamforming method in impulsive noise modeled as S α S (Symmetric α -stable) processes is proposed.The method firstly defines fractional lower-order array response and then develops a fractional lower order minimum variance distortionless response (FrMVDR) beamformer,based on the conventional minimum variance distortionless response (MVDR) beamformer.It is shown theoretically that the fractional lower order array output power is bounded when the fractional lower order is less than half of the characteristic exponent of the noise.Computer simulations show that the FrMVDR beamformer has superior performance in both Gaussian and non-Gaussian impulsive noise environments in comparison with the MVDR and other related fractional lower order moment (FLOM) based beamformers.Hence the proposed beamformer is a robust one.关键词：impulsive noise;adaptive beamforming;minimum variance distortionless response;symmetric α -stable distribution0|2|12更新时间：2025-07-02
- 摘要：The local area augmentation system (LAAS) is the federal aviation administration's (FAA's) ground-based augmentation system (GBAS) for local area differential GPS (DGPS).The local area augmentation system ground facility (LGF) is intended to provide performance capable of supporting various precision approach and landing operations.Multiple reference consistency check (MRCC) is the centerpiece of the LAAS integrity monitor on LAAS ground facility.It ensures that the pseudorange correction error do not exceed a given value with testing and estimation of these pseudorange correction errors.The paper discusses the signification of B-values that are the principal output of MRCC.Also,the magnitude of B-values and non-fault level is analyzed by the result of experimentation.It confirms that B-values are small generally,and B-vaules exceed their thresholds with a fault occurred.关键词：multiple reference consistency check;local area augmentation system (LAAS);B-value;integrity;pseudorange correction errors0|2|7更新时间：2025-07-02
- 摘要：Current high resolution airborne SAR systems aim to produce SAR imagery at resolution less than 0.1m.This demand poses a lot of technological and methodological problems,which have to be solved.The most important problem is bandwidth management.It can be realized by means of the synthetic bandwidth technique,an advantage of which is the reduction of the instantaneous bandwidth and sampling rate requirements of the radar system.This paper demonstrates two time domain synthetic bandwidth methods,which are respectively applied to basal receive and deramp receive mode.Based on analysis of the processing steps of original methods,the modified methods are proposed,and some issues arising in practical implementation of the technique are discussed.More particularly,the parameters choice and the overlap division processing steps of the second method in wide swaths are pointed out specifically.Moreover,according to the spectral representation of the received signal,an approach of conversion from single center frequency SAR raw data to stepped center frequencies SAR raw data is brought forward,and some results of verification of these methods are shown.关键词：synthetic bandwidth;high range resolution;airborne SAR0|2|10更新时间：2025-07-02
- 摘要：An efficient method of moment with Costa's basis function is introduced to analyze the EMC of multiple antennas mounted on complex shaped conductors.Too much time and prohibitive computation resources are needed for the EMC analysis of complicated EM environment.To overcome this drawback,a parallel algorithm that combines MoM with MPI functions is studied.The tessellation scheme is employed for parallel filling the impedance matrix and Parallel Conjugate Gradient method is used to solve the matrix equation.Several numerical results are presented to demonstrate its accuracy and efficiency.关键词：Mom;multiple antennas;EMC;parallel computation;PC clusters0|2|6更新时间：2025-07-02
- 摘要：The unconditionally stable alternating-direction-implicit-finite-difference-time-domain(ADI-FDTD) method is extended to dispersive media—isotropic plasma based on the PLCDRC(Piecewise Linear Current Density Recursive Convolution) method.Two-dimensional ADI-FDTD formulations for isotropic plasma are derived.The proposed method is applicable to arbitrary dispersive media.Finally,in order to demonstrate the effectiveness of this approach,two examples are calculated,the numerical results of ADI-FDTD for isotropic plasma are in good agreement with the results obtained by conventional FDTD method,but compared with conventional FDTD method,the proposed method is efficient without requiring additional memory.关键词：ADI-FDTD;piecewise linear recursive convolution method;isotropic plasma0|2|4更新时间：2025-07-02
- 摘要：It is important for multi-constrained QoS routing to study the pertinences of QoS metrics.This paper investigates the pertinence of bandwidth,average packet delay and delay jitter in mobile ad hoc networks by simulation and analysis.The formulations denoting the pertinence of these QoS metrics are obtained,and simulations are performed to validate correctness of these formulations.The simulation shows that the analytical results are consistent with simulation results.关键词：mobile ad hoc networks;QoS;pertinence0|2|1更新时间：2025-07-02
- 摘要：Based on the measurement model of inverse synthetic aperture radar within a small aspect sector,two imaging methods,named as FFT-based united algorithm and two-dimensional decoupled algorithm,are presented with the application of sparse component analysis.These methods can form ISAR images with higher resolution from compensated incomplete measured data,improve the clarity of the images and make the feature structure much clear which are helpful for target recognition.The decoupled algorithm can be combined with the process of motion compensation so as to improve the compensation precision.The numerical results of a typical space target indicate that FFT-based united algorithm can provide clear ISAR images with high contrast and the decoupled algorithm is computationally efficient.Both algorithms can meet the demand of real-time or quasi-real-time imaging.关键词：inverse synthetic aperture radar;sparse component analysis;supper-resolution;FFT0|2|8更新时间：2025-07-02
- 摘要：In pattern classification system,many irrelevant and redundant features will lessen the performance of classifiers.So it is important to select features.This paper proposed a discrete binary version of particle swarm optimization-support vector machines (BPSO-SVMs) wrapper mode feature selection algorithm.At first,a population of particles (feature subsets) was randomly generated.Then BPSO algorithms searched the feature space guided by the result of SMVs' 10-fold crossover validation.After numbers of iteration,the best fitness feature subset was selected out to train the predictor.Experiments on two datasets (Segmentation and Ionosphere) in UCI machine learning repository confirm the effectiveness of the proposed strategy.关键词：particle swarm optimization;support vector machine;feature subset selection0|2|17更新时间：2025-07-02
- 摘要：Based on the convergence of bounds for the entropy rate of binary hidden Markov processes,a numerical approach is advanced.The algorithm can approximate to true value of the entropy rate below a predefined error,and the accuracy can also be estimated.Since the logarithm of the algorithm's complexity is linear to the logarithm of error,the cost of the algorithm is acceptable for practical use in engineering fields.It casts light to solve the problem of computing the entropy rate of more generalized kinds of HMPs.关键词：binary hidden Markov processes (BHMPs);entropy rate;asymptotic approximation0|2|0更新时间：2025-07-02
- 摘要：A novel k-out-of-n threshold scheme for visual secret sharing is proposed.The construction scheme of basic matrix is brought forward from the approximate best optimized solution of the equation set which is established on the basis of contrast condition and security condition of the visual secret sharing.The proposed method analyses the (k,n) and (n,n) schemes uniformly and brings them into an integral framework.Furthermore,a fraction of algorithm operations were replaced by theoretical analysis in the new scheme.Consequently,it achieves higher efficiency with same security intensity compared with the previous schemes.关键词：threshold;secrest sharing;visual cryptography0|2|7更新时间：2025-07-02
- 摘要：Timing and frequency synchronization and channel estimation can affect each other in OFDM system.This paper investigates a combined estimation scheme based on one training signal which is defined in the IEEE 802.11a WLAN system.The scheme includes two stages for performance improvement and simplicity.At the first stage,the coarse timing and frequency offset and channel response are obtained.The fine synchronization and channel response based on the coarse stage are obtained at the second stage.The simulation results show the effectiveness of the proposed estimation.关键词：synchronization;channel estimation;maximum likelihood;OFDM;WLAN1|2|5更新时间：2025-07-02
- 摘要：The advance of the vacuum microwave electronics in recent 10 years has been described in this paper.The vacuum microwave electron devices will continue to be used in the defense equipments in the future 30 years and more longer.The high power TWTs,microwave power modules (MPM),multi-beam klystrons,gyrotrons and vacuum microelectron devices are still the key devices for military equipments.The combination or mixing of the vacuum electron devices and semiconductor devices will create a new generation of high power microwave electron devices,which will have features from both sides.关键词：high power;microwaves;vacuum;electron device0|2|25更新时间：2025-07-02
- 摘要：The Green function of wide-angle parabolic equation (WAPE) in boundless plane is constructed based on the split-step Fourier transform (SSFT) algorithm.A method for calculating the initial fields of WAPE by using the Green function is presented.Based on this method,wave propagation on sea surface by a Gaussian current source is calculated by using the WAPE.Results comparison between the WAPE,the two ray model of geometrical optics (GO) and the Green function itself testifies the correctness of the Green function.Accordingly,the groundwork of a new approach so-called assistant potential function method for calculating the PE is established.关键词：SSFT;WAPE;Green function;initial fields0|2|6更新时间：2025-07-02
- 摘要：The innovation filtering interacting multiple model estimator (IFIMM) performs more accurate result than conventional IMM,but it may be imposed to slow down the model switching.An adaptive Markov parameter IFIMM algorithm (AMP-IFIMM) is proposed,in which the Markov transition probabilities can be modified adaptively during the process of filtering.By omitting the information of non-matching model and magnifying the matching model information simultaneously at the switching time,the algorithm can meet both the requirements of accuracy and switching speed.The application of the algorithm on CV-CA two model integrated navigation system takes out reasonable result.关键词：interacting multiple model;innovation filtering;Markov chain;integrated navigation0|2|18更新时间：2025-07-02
- 摘要：Electromagnetic transient analysis of high-voltage cable system has significant practical meaning on the engineering problems,e.g.over-voltage protection,insulation coordination and electromagnetic interference.Frequency-dependent characteristics of both distributed parameters and phase-modal transformation matrices need to be taken into account for traditional method,e.g.EMTP software.Based on the finite difference time-domain (FDTD) method,a novel model is presented for transient analysis of power cable system.In this model,only frequency-dependent characteristic of cable's impedance parameters needs to be considered in phase domain.Compared with other models,the proposed model is demonstrated to be correct.As an extension,this model is improved for transient analysis of coaxial cable system.The calculated results are in good agreement with the experimental results.关键词：power cable;coaxial cable;electromagnetic transient;finite difference time-domain0|2|2更新时间：2025-07-02
- 摘要：Based on passive array radar,the case of direction-of-arrival (DOA) estimation in presence of strong jamming or signal is studied,and a new approach called Jamming Jam Method (JJM) is presented in this paper.The method use the information of the strong jamming is known to construct a jam matrix,and then estimate signal DOA of the low signal noise ratio in one sector.The JJM has slight computation burden compared with the RELAX method,high-order cumulate method,and cyclostationarity algorithms.关键词：direction-of-arrival;passive array radar;jamming suppression0|2|34更新时间：2025-07-02
- 摘要：A new scheme for approximating the solution of 2D Maxwell's equations using the symplectic scheme is introduced.The scheme is obtained by discretizing the Maxwell’s equations in the time direction based on symplectic scheme with different orders,and then evaluated the equation in the spatial direction with a second or fourth order finite difference approximation.The stability condition and numerical dispersion of the schemes with different orders are derived.The results are demonstrated by theoretical analysis and numerical simulation,the stability and numerical dispersion of the scheme with first and second order symplectic scheme (T1S2、T2S2) are identical to FDTD with a second order approximation in spatial direction .Although the high order schemes have almost the same stability as the FDTD,the fourth order scheme with a fourth order approximation in spatial direction(T4S4) has the superior numerical dispersion—isotropic properties of the scheme.Numerical results show that high order symplectic scheme is superior compared with FDTD for solving two-dimensional TMz case.关键词：Maxwell's equations;symplectic scheme;stability;numerical dispersion;finite difference time domain0|2|6更新时间：2025-07-02
- 摘要：Based on multilevel fast multipole algorithm (MLFMA),some large target-scale problems can be solved efficiently under limited computer resources now.The translation computations cost primarily in MLFMA.The methods to store and compute translation operators are also amenable for the efficiency of MLFMA.In this paper,an efficient modified Lagrange interpolation technique is developed for fast evaluation and low storage of translation operators.The translation operators with different space distance between source group and field group are computed rapidly by local interpolation after introducing a modified factor on space-distance.Compared with conventional methods for translation operators in MLFMA,the present technique reduces greatly the CPU time and memory requirement for translation operators.On the other hand,it maintains a reasonable and stable computation accuracy.关键词：electromagnetic scattering;multilevel fast multipole algorithm;translation operator;modified interpolation0|2|3更新时间：2025-07-02
- 摘要：This paper explores data fusion of distributed multisensor dynamic systems,these sensors hold different sampling rates.For the proportion between them is usually rational;a new fusion algorithm based on asynchronous sampling data is proposed.Firstly,the new algorithm maps and unifies all measurements in the reference frame and clock with fusion centre.Secondly,using the difference between predict value to object state of next time and state estimate value of this time,we establish the dynamic model between object state vector of every sampling point in the fusion period.Thirdly,combining the new established model with traditional Kalman filter,every state in this period can be estimated and updated by obtaining orderly measures.Finally,the next state estimate or predicted estimate may be got by global information after all state estimates relative to all observation point in this period have been obtained in turn.With introducing the basic idea of the new algorithm,the processes to win it are presented step by step.Using of computer simulation in terms of comparing the results utilizing the new algorithm with those based on time calibrated method via estimate accuracy,the good performance arising from this new approach has been effectively validated.关键词：multisensor system;rational rates;asynchronous data fusion;modeling0|2|3更新时间：2025-07-02
- 摘要：After analysis of requirements of traffic flow monitoring,an efficient,accurate flow classification algorithm is proposed.The algorithm divide the flow classification process into three phases,and each phases reduces the dimensions of flow classification.The experience shows that when tha list table length equals 300,the classification process time for successful searching and updating or unsuccessful searching and new record inserting is 1.8 μ and 1.3 μ s.And the classification ability is 0.55 and 0.77 million packets per second.关键词：traffic flow measurement;flow classification;algorithm0|2|2更新时间：2025-07-02
- 摘要：The particle filter can give the approximate solutions to the non-linear non-Gaussian model of mobile robot global localization.However,if the new measurements appear in the tail of the prior or if the likelihood is too peaked in comparison to the prior,the conventional particle filter can degenerate and make localization fail.We present a novel algorithm that combines an importance sampling with central difference filter (CDF).The posterior pose state density is represented by Gaussian mixture model (GMM) that is recovered from the weighted particle set of the measurement update step by means of a weighted expectation maximization (WEM) adaptive clustering algorithm,which based on the kd-trees.Experimental results show that this new approach has an improved localization accuracy and reduceds computational complexity.关键词：mobile robot;global localization;particle filters;central difference filter(CDF);weighted expectation maximization(WEM);Gaussian mixture model(GMM)0|2|6更新时间：2025-07-02
- 摘要：Recent biological experiments have presented increasing evidence for object-based attention.We propose a computational model of object-based attention to simulate biological perception.Two techniques are employed:multi-scale analysis and grouping.Differential geometry descriptor in multi-scale analysis extracted important edges from source images and subsequent contour grouping process organized the edge image into perceptual objects.The later process originated from Gestalt laws.Then focus of attention shifted among objects in order of conspicuousness,which was measured by edge saliency,region contrast and topological property of closure.The proposed model exhibits several advantages.It considers integrality of objects and thus gains higher searching accuracy than space-based attention.It uses multi-scale analysis to select candidates and thus improves efficiency of contour grouping.Experiments on different types of images show high efficiency and biological plausibility of our model.关键词：biology perception;multi-scale analysis;grouping;object-based attention0|2|5更新时间：2025-07-02
- 摘要：With the development of e-commence and other utilities on internet,a new security service——fair non-repudiation becomes more important and crucial.But,most current protocols depend on trusted third party(TTP),so a fair non-repudiation protocol without TTP is needed.But the existing fair protocols don't have equal security for message originator and receiver,and they can not assure the security of the message originator.In this paper,a new protocol is designed for the prior security of the originator,and a fair non-repudiation protocol without TTP based on entity's computing power is proposed to get rid of the dependence on TTP,to solve the security problems that exist when message originator and receiver's computing power are not equal.关键词：fair non-repudiation;digital signature;trusted third party0|2|4更新时间：2025-07-02
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A Multiplexing-Based TCP-Friendly Congestion Control Mechanism for Multimedia Streaming Applications
摘要：This paper focuses on the tradeoff between the TCP-friendliness and the minimum rate threshold of multimedia flows in multiplexing environments,and proposes a multiplexing-based TCP-friendly rate controlling algorithm—MTCRC.It keeps the average throughput of multimedia flows friendly when they are multiplexing and the friendly rate is lower than the restricted minimum rate by hanging up some flows on proper occasion.It also improves TFRC (TCP-friendly rate control) and maintains the favorable rate smoothness of TFRC.Meanwhile the characteristic of the minimum-rate threshold of multimedia flows and multiplexing environments are taken into consideration,so MTCRC can keep multimedia flows available,share bandwidth fairly with TCP flows.The results of simulating show that MTCRC outperforms TFRC.关键词：multimedia streaming;TCP-friendly;congestion control;multiplexing0|2|2更新时间：2025-07-02 - 摘要：An information fusion algorithm based on the quantum neural networks for the pattern recognition with overlapping classes is presented,and it is used in the photovoltaic radar electronic equipment fault diagnosis.By measuring the temperature and voltage of circuit component,the membership functional assignment of two sensors to circuit component is calculated,and the fusion membership functional assignment is gained by using the multi-level transfer function quantum neural networks(QNN),then according to the fusion data,the fault component is found.Comparing the diagnosis results based on separate original data with the ones based on QNN fused data,it is shown that the quantum fusion fault diagnosis method is more accurate.关键词：quantum neural network;Information fusion;fault diagnosis;patter n recognition0|2|9更新时间：2025-07-02
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