最新刊期
卷 44 ， 期 5 ， 2016
- 摘要：A new complex exponential function is defined to map the real and imaginary parts of a classic 16-QAM nonconstant modulus signal to the unit circle, respectively.With the relationship between the real and imaginary parts of the new constellation after mapping, a new cost function is built and then a new blind equalization algorithm is proposed.The proposed algorithm can converge the steady-state mean square error (MSE) to zero under a noiseless environment, which is different from the famous constant modulus algorithm (CMA) and some CMA-based improved algorithms.In addition, we provide the theoretical analysis of the proposed algorithm.Simulation results demonstrate that the proposed algorithm has the lower steady-state MSE than CMA and some CMA-based improved algorithms.关键词：blind equalization;constant modulus algorithm;complex exponential cost function322|1065|2更新时间：2025-07-16
- 摘要：In view of the resource scheduling problem of Hadoop Yarn, to improve the execution efficiency of the cluster job, we propose a Self-adapt Resource Scheduling algorithm based on Ant Colony Algorithm and Particle Swarm Algorithm in Hadoop (SRSAPH).In SRSAPH, we initialize the pheromone matrix of SRSAPH by using the attribute information of load, memory, and CPU speed obtained through the heartbeat message transfer mechanism.Meanwhile, we introduce the self-cognitive ability and social cognition ability of particle swarm algorithm into the ant colony algorithm to speed up the rate of convergence of the algorithm.Moreover, we dynamically adjust the pheromone evaporation rate based on the fluctuation trends of global optimal solution to enhance the accuracy of the solutions.Experimental result shows that by using SRSAPH in resource scheduling, the execution time of cluster job is shorten by 10%.关键词：resource scheduling;ant colony algorithm;particle swarm algorithm;Hadoop Yarn317|762|3更新时间：2025-07-16
- 摘要：To deal with the problem of blind estimation of spreading codes and information sequences for space-time block coded multi-carrier CDMA signals, combined with SMC (Sequential Monte Carlo) and Kalman filtering techniques, this paper introduces a fast blind despreading algorithm by making full use of the orthogonality property of the STBC and the OFDM multi-carrier modulation.Firstly, the proposed algorithm segments the signal model through different symbols and antennas.Secondly, use Kalman filtering method to update the mean and covariance iteratively.Then, use a set of properly weighted samples to approximate the joint posterior distribution, Finally, exploit these samples to estimate the quantity of interest, which improve the computational efficiency greatly.The theoretical analysis and simulation results verify the effectiveness of the proposed algorithm.关键词：spread spectrum communication;code division multiple access;space-time block coding;sequential monte carlo;spreading code;information sequence249|349|3更新时间：2025-07-16
- 摘要：In order to improve the overestimation of ocular artifacts (OA) in electroencephalogram (EEG) and the OA removal effect of nonlinear mixture caused by environmental interference coupling, a novel automatic removal method is proposed based on fast kernel independent component analysis (FastKICA) and discrete wavelet transform (DWT), and it is denoted as FKIWT.The independent components are separated from the mixed EEG by using the FastKICA algorithm, and the correlation coefficient is applied to identify OA component;Then, the Multiresolution analysis of OA is achieved with DWT, the approximation wavelet coefficients are set to zero and the detail wavelet coefficients are not changed.So more useful EEG is remained in the reconstructed OA component;Furthermore, the clean EEG is restored with the inverse algorithm of FastKICA.The experimental results show that FKIWT can effectively improve the overestimation of OA and has perfect anti-interference ability and robustness.Meanwhile, the better effects of OA elimination are also obtained on the condition that the linear or nonlinear mixed model is adopted, and the latter's advantage is especially obvious.The FKIWT is suitable for on-line application.关键词：nonlinear mixed model;fast kernel independent component analysis;discrete wavelet transform;overestimation of ocular artifacts;robustness250|689|3更新时间：2025-07-16
- 摘要：Energy is one important bottleneck to the development of intelligent portable device.With the wide use of embedded operation system, the energy bug caused by unsuitablely using the API of the operation system has become the important factor in the designment of the embedded application.According to the characteristics of the No-Sleeping energy bug, a symbolic execution based energy bug detecting method is proposed to reduce the energy bug.It first uses intraprocedural analysis technology to analyze one function independently to get the energy information of the function.Then, the interprocedural analysis technology is applied to get the globe analysis of the program by the information of intraprocedural analysis which can get more accuate information for energy bug detection.Meanwhile, constraint solver can be combined to obtain the counter-example for locating the position of the error.Example and experiment results verify that the method is feasible and effective in energy bug detection.关键词：energy bug;symbolic execution;bug detection;intraprocedural analysis;interprocedural analysis275|482|2更新时间：2025-07-16
- 摘要：To calibrate the camera, a linear iteration camera self-calibration method based on non-rigid is presented in this paper.Assumed that the non-rigid is a linear combination of some shape basis, the projective reconstruct can be obtained by using the fact that the image matrix which consists of all the image points and all the depth factors is low rank.Then, the camera calibration can be linear iteration realized based on the camera constraints.The presented method can overcame the shortcoming that the existing self-calibration method can only deal with the rigid.The experiment results with both simulate and real data show that the presented method can efficiently realize the camera self-calibration.关键词：non-rigid;self-calibration;factorization225|538|2更新时间：2025-07-16
- 摘要：Service description file, which is fundamental for the service-oriented architecture, can be used by the IoT sensing devices to accelerate resource discovery and searching processes.Currently, these files are mostly written manually by the device developers, this process is inefficient and fallible.The state-of-art method SPITFIRE can generate the devices' description in a semi-automatic way, but its configuration can be trivial and its accuracy still can be improved.In this paper, we proposed a novel automatic device description method, with which devices can automatically generate their individual description.We designed a clustering algorithm based on DBSCAN to infer the description of sensing device, taking advantages of existing descriptions and the data features of series gained by data sampling.A metric learning algorithm is also implemented to optimize the parameter used by the clustering algorithm.All the routines run independently on different devices, and no manual intervention is needed during the self-description process.Through simulation, we show that this method has a prominent advantage of precision over other state-of-art methods, making our method more suitable for the massive IoT devices.关键词：Internet of Things;massive device;description file;distributed;optimization;clustering243|524|0更新时间：2025-07-16
- 摘要：A method of image interpolation with non-local feature directions is proposed.This method respectes the smooth of the contour profile of interpolated image and retrains blur edges.The eigenvector of the non-local Hessian matrix is considered as the image featrue direction.The diffusion of image energy functional is controlled by the eigenvalue of image local Hessian along the direction.It overcomes the local limit of gradient pointing image feature and drives image energy functional to diffuse along corrected direction.Thus the blur of image feature is avoids.Numerical experiments on real images show that images interpolated by the proposed method have better interpolated edges and are almost artifact-free.关键词：non-local gradient;non-local curvature;total variation;variational methods;image interpolation215|461|1更新时间：2025-07-16
- 摘要：Multi-objective evolutionary algorithm that diversifies population by its density (MODdEA) solve multi-objective optimization problem according to the non-dominated sorting information and spatial density information, the algorithm has a good performance in the comparison with other multi-objective evolutionary algorithm.In this paper, we propose an improved multi-objective evolutionary algorithm MODdEA + based on MODdEA.Firstly, we propose a operator named clone operator based on the partition mechanism in search space, this operator could not only improve the global search capabilities in the early stage of evolution, but also enhance the local refinement capabilities in the late stage of evolution;secondly, we introduce a evaluation strategy which evaluate the individuals in Pareto information list based on the dominate and dominated information, this strategy provide a more accurate sorting result;finally, we improve the mutation operator in order to reduce the probability of overstep of the boundary.To demonstrate the effectiveness of the improved algorithm, we compare it with MODdEA on multiple testing problems, the experimental results show that the improved algorithm's solving quality is much better than the original algorithm's.关键词：evolutionary algorithm;density-driven;clone operator;raw fitness;mutation operator249|958|1更新时间：2025-07-16
- 摘要：With the enlargement of the scale of POMDP problems in applications, the research of heuristic methods for reachable area based on the optimal policy becomes current hotspot.However, the standard of existing algorithms about choosing the best action is not perfect enough thus the efficiency of the algorithms is affected.This paper proposes a new value iteration method PBVIOP (Probability-based Value Iteration on Optimal Policy).In depth-first heuristic exploration, this method uses the Monte Carlo algorithm to calculate the probability of each optimal action according to the distribution of each action's Q function value between its upper and lower bounds, and chooses the maximum probability action.Experiment results of four benchmarks show that PBVIOP algorithm can obtain global optimal solution and significantly improve the convergence efficiency.关键词：partially observable Markov decision process (POMDP);probability-based value iteration on optimal policy(PBVIOP);Monte Carlo method232|702|4更新时间：2025-07-16
- 摘要：Although the VNA calibration theory, at present, has been much mature, measurement uncertainty inevitably exists in practical measurement, due to random errors, linearization and measurement conditions, etc.In the existing VNA measurement uncertainty evaluation algorithms, only residual systematic error is considered, with the ignorance of the influence of system's nonlinearity, random error caused by connector and cable performance and environment conditions.In this paper, four categories of measurement error are taken into account, including residual system error, system's nonlinearity, random error and environment conditions of the measurement.Thus the rational and complete model for uncertainty in measurement is put forward and the uncertainty evaluation method for complete measurement system of VNA is established.Compared with the current VNA measurement uncertainty evaluation algorithms, a more comprehensive consideration of error factors is presented in this algorithm, leading to more reliable assessment results.The formulae of the uncertainty of S-parameter measurement are deduced in term of the theory of error limit transfer, and the corresponding method to get the error parameters is given.The algorithm is applied to measurement uncertainty evaluation for the vector network analyzer Agilent 8573ES and the results are in great agreement with the technical data provided by Agilent.关键词：vector network analyzer;error model;S-parameter;uncertainty332|1327|1更新时间：2025-07-16
- 摘要：To overcome the shortcomings the traditional particle swarm optimization algorithm (PSO), such as poor ability to escape a local optimal, premature convergence and low precision, we proposed a new PSO based on multiscale-selective-learning and detecting-shrinking strategies, which called MDPSO in short.In the multiscale-selective-learning strategy, a particle executes a multiscale learning process to improve its studying efficiency by adopting its topology, selecting neighbors, and choosing target variable dimensions.In the detecting-shrinking strategy, particles' historical best solutions are periodic sampling and some useful information, which extracting from the sampling results, is used to direct the best solutions to carry out a detecting operation.The aims of the strategy are to improve PSO's global searching ability and to help the population escape a local optimal solution.While the best solution situating around a global optimal solution, the algorithm implements the shrinking strategy to confine the search space to a small one the aims of which are to improve the PSO's exploitation ability and to increase the accuracy of the solutions.The proposed method was applied to twenty-two typical benchmark functions, and the comparisons of the performance between MDPSO and other eight PSO algorithms were experimented.The results suggest that the proposed strategies can effectively overcome the premature convergence, speed up the convergence and improve solutions accuracy.关键词：particle swarm optimization;premature convergence;multiscale learning;detecting strategy236|951|4更新时间：2025-07-16
- 摘要：Broadcast encryption allows a sender to securely broadcast to any subset of the group members.However, its security heavily depends on broadcast centre to generate and distribute decryption secret keys for group members.In order to solve the above problem, we propose the notion of certificate-based broadcast encryption, describe the formal definition and security model of the certificate-based broadcast encryption.Furthermore, we also provide an efficient certificate-based broadcast encryption scheme.In our scheme, the decryption key includes user's private key and a certificate, where the private key is chosen by user himself, and the certificate is generated by certification authority.Therefore, our scheme overcomes the key escrow problem.In addition, our scheme is efficient, because it needs only one paring in decryption algorithm and paring operation in encryption algorithm can be pre-computed.关键词：broadcast encryption;certificate-based encryption;bilinear paring205|534|3更新时间：2025-07-16
- 摘要：Certificateless aggregate signature is proposed to solve the key escrow problem and the complex certificate management problem.If the private key of any signer is exposed, the certificateless aggregate signature generated by the users including this signer will no longer be secure.To mitigate the damages of key-exposure in certificateless aggregate signature, we firstly integrate the key isolation mechanism into certificateless aggregate signature, and proposed the definition of key-insulated certificateless aggregate signature and its security model.We give a practical scheme, which achieves the periodical update of the signer's secret key by the interaction with the helper.We prove the proposed scheme is secure in the random oracle model, i.e., the scheme has key insulated security, strong key insulated security and secure key updates.关键词：aggregate signature;key insulation;certificateless signature;key escrow;bilinear pairings263|505|4更新时间：2025-07-16
- 摘要：This paper analyzes the traditional anonymous roaming authentication protocol, and pointed out the deficiencies of their anonymity is not controlled and the communication is delay.The controllable anonymous roaming authentication protocol proposed in this paper for heterogeneous wireless networks, which can be completed to verify the legitimacy of the identity of the mobile terminal through a message interaction.If the mobile terminal has malicious operation, the home network authentication server can help remote network authentication server to revoke the identity anonymity of the mobile terminal.This is a protocol in anonymous authentication, at the same time, and which effectively preventing the occurrence of malicious behavior, and the communication delay.This protocol is safe in the CK security model.关键词：heterogeneous wireless network;controlled roaming;anonymous authentication;CK security model228|992|5更新时间：2025-07-16
- 摘要：How to provide differentiated services for diverse types of traffic poses challenges to the retrieval process of Content Centric Networking (CCN).Inspired from the idea of differentiated service, a diverse content delivery scheme based on traffic types is proposed.When requesting contents, three delivery models, namely, persistent push, parallel prediction and one-one request, are proposed according to the characteristics of the requested traffic.When making the caching decision, three on-path caching policies, including transparent forwarding, probabilistic edge caching and gradual push are implemented respectively to match the delivery models.The simulation results show that the scheme can decrease the request latency, achieve higher cache hit ratio, while improving the overall performance of content delivery with a small amount of additional control overhead.关键词：content centric networking;differentiated service;caching strategy;traffic type186|586|4更新时间：2025-07-16
- 摘要：A novel hardware Trojan detection method based on heuristic partition and optimal test pattern generation is proposed.First, we use a scan cell distribution based heuristic partition to divide the circuit into regions.Then, we propose a test vector ordering algorithm to generate near-optimal test patterns based on the circuit's structure.Lastly, we activate each region separately and perform localized IDDT analysis to detect hardware Trojans while a signal calibration technique is used to eliminate the effect of process variations and noises.The benefits of this approach are that it can magnify detection sensitivity, eliminate the effects of process variations and noises, ensure the scalability of hardware Trojan detection facing large scale ICs, and determine Trojan's location.We evaluate our approach on benchmark circuits and the experiment results show that the detection sensitivity is greatly improved.关键词：hardware security;hardware Trojan detection;heuristic partition;optimal test pattern generation234|586|4更新时间：2025-07-16
- 摘要：A novel online learning object detection system is proposed, which can self learning and improve its detection performance wihout human-annotated training data.The system is composed of a object detection module and a sample labeling module.Online fern classifier is used in the object detection module because of its fast online learning speed.Consequentely, our system can learn automatically and detect objects in the real time.Samples, which are used to train the classifier online, are acquired and labeled automatically from a two stages cascade method in the sample labeling module.Instead of training initial classifier from some manual labeled training samples like other online learning detection frameworks, our system can learn automatically after specifying the object to be detected.This can greatly reduce the efforts of labelers.Experimental results on several video datasets are provided to show the adaptive capability and high detection rate of our system.关键词：online learning;visual perception;fern classifier;object detection238|370|4更新时间：2025-07-16
- 摘要：Filter design is the signification foundation for system identification and state estimation.Based on the realization construction of state prediction and measurement update, Kalman filter can obtain the optimal estimation of state estimated under the linear minimum variance criterion, but the filtering precision is vulnerable to the random characteristics in single sensor condition.A novel realization structure of Kalman filter based on measurement lifting strategy is proposed in the paper.At first, virtual measurement is constructed on the basis of latest measurement and the prior statistical information of measurement noise modeling.Then, virtual measurements are reasonably sampled and fusion to modify the measurement reliability, and the estimation precision is improved.In addition, aiming to the algorithm requirements including real-time, precise and robustness in engineering application, the distributed weight fusion structure and the centralized consistency fusion are designed respectively.Finally, the theoretical analysis and experimental results show the feasibility and efficiency of algorithm proposed.关键词：Kalman filter;measurement lifting strategy;distributed weight fusion;centralized consistency fusion228|959|5更新时间：2025-07-16
- 摘要：In non-contiguous orthogonal frequency-division multiplexing (NC-OFDM) based cognitive radio systems, conventional active interference cancellation (AIC) and extended AIC (EAIC) schemes use the same rectangular waveform of the same length for all canceling carriers (CCs), leading to the limitation of performance improvement of side-lobe suppression or inter-carrier interference (ICI) reduction.In this paper, a novel variable cancellation basis was proposed for side-lobe suppression in NC-OFDM cognitive radio systems based on the observation that CCs in different frequency have non-uniform attribution for sidelobe suppression.So, CCs are grouped by frequency locations and shaped with different waveforms of different lengths to satisfy good side-lobe suppression performance while reducing ICI at the same time.Numerical results show that, with the proposed CC scheme, NC-OFDM signal's side-lobe can be suppressed to -60 dB with negligible signal-to-noise ratio loss at a symbol error rate of 10-5 with 64 quadratic-amplitude modulation symbol.关键词：cognitive radio;non-contiguous orthogonal frequency-division multiplexing;side-lobe suppression;active interference cancellation167|568|2更新时间：2025-07-16
- 摘要：We propose to apply the surface acoustic wave (SAW) temperature sensor in the temperature control system of library and archive.When the temperature of library and archive changes, the output frequency of the SAW temperature sensor is linear with the temperature, thus the temperature can be measured.We also present the trace weighted function of the input transducer, and the influence of transducer electrode-numbers on the SAW power as two key problems of the SAW temperature sensor.The solutions to these problems are achieved in this study.The wavelet function is used as the trace weighted function of the input transducer, so that the sidelobes for the frequency characteristic curve of the SAW temperature sensor are suppressed.The more the transducer electrode number are, the weaker the bulk acoustic wave (BAW) is (i.e., the more the transducer electrode-numbers are, the stronger the SAW is).As long as transducer electrode numbers are more than 40, the excited bulk acoustic wave (BAW) can be ignored, but the excited SAW is very strong.The design, fabrication and experiment for the SAW temperature sensor have been studied in detail.关键词：library and archive;surface acoustic wave (SAW) temperature sensor;sidelobes;transducer electrode numbers215|541|1更新时间：2025-07-16
- 摘要：Blurry image can be represented as the convolution of a latent image and a blur kernel, so it is an ill-posed problem to solve the kernel and the latent image inversely from a single blurry image.The most effective way to solving ill-posed problem is using cost function with priori term.For blind image deblurring problem, we propose a ratio of convex norm to concave norm as a regularization priori term, which has more sparse representation ability.When solving the model by variable splitting method, we propose L1 norm fidelity term to update high-frequency information of the latent image.At the stage of updating the blurring kernel, we propose a linear increasing weight parameter to estimate the blurring kernel gradually by multi-scale approach from coarse to fine.After obtaining the blur kernel, we use a closed threshold formula to estimate the latent image.This method can obtain high-quality image efficiently.The experimental results demonstrate the effectiveness of the model and the rapidity of the algorithm.关键词：ratio of concave norm to convex norm regularization;blind image deblurring;variable split method;closed-form threshold153|645|8更新时间：2025-07-16
- 摘要：Location of sensor plays a pivot role in WSNs.Most of the localization algorithms can achieve extremely high positioning accuracy in line of sight (LOS) environment.However, they are unable to obtain ideal accuracy due to the obstacles in non-line of sight (NLOS) environment.In order to solve the NLOS propagation problem in indoor environment, we propose an indoor localization method based on RTT and AOA using a lightweight grid-based clustering (LGBC) algorithm.The LGBC algorithm does not depend on any prior information of indoor environment and possesses significant flexibility.The simulation results show that LGBC algorithm has low time complexity and small computational overhead.Furthermore, it outperforms the other method by about 65 percent in terms of localization accuracy.关键词：WSNs(wireless sensor networks);indoor localization;NLOS(non line of sight) environment;clustering230|771|16更新时间：2025-07-16
- 摘要：More and more complex multi-objective optimization problems have emerged in the real world.Inspired by the idea of hybrid components of multi-objective optimization algorithms, a method of fireworks explosion optimization and a strategy of elite opposition-based learning were introduced into the field of multi-objective optimization.A multi-objective fireworks optimization algorithm using elite opposition-based learning (MOFAEOL) was proposed in the paper.The MOFAEOL utilized the elite opposition-based learning strategy to strengthen the global search ability, and adopted the fireworks explosion optimization approach to improve the local search ability and the accuracy of the algorithm.These two learning mechanisms collaborated to balance the global exploration and the local exploitation, in order to solve some hard multi-objective optimization problems efficiently.The MOFAEOL was compared with other five typical multi-objective optimization algorithms on a benchmark test set including 12 multi-objective optimization test problems composed by ZDT and DTLZ series functions.Experimental results show that the MOFAEOL is superior or competitive to the other peer algorithms in convergence, diversity and stability.关键词：fireworks explosion optimization;elite opposition-based learning;multi-objective evolutionary algorithm225|737|12更新时间：2025-07-16
- 摘要：Image super-resolution reconstruction via Improved Dictionary Learning based on Coupled Feature Space is studied in the paper, in order to solve the following problems:1 the dictionary training process is time-consuming, 2 the results are not satisfactory in the existing algorithms.In the proposed algorithm, at first, the Gaussian mixture model clustering algorithm is employed to cluster the training image blocks, secondly, quickly obtain high and low resolution feature space of dictionary and mapping matrix by using dictionary updating based on improved KSVD dictionary learning algorithm, and then, the Super-Resolution image is reconstructed according to the likelihood probability of test samples, in which each category adaptively selected the most matching dictionary and mapping matrix for high-resolution reconstruction, finally, the non-local similarity and iterative back-projection are exploited to furtherly improve the quality of the reconstruction image.The experimental results demonstrate the validity of the proposed algorithm.关键词：super-resolution;dictionary-learning;ksvd;sparse representation;gaussian mixture model222|540|6更新时间：2025-07-16
- 摘要：Metamorphic testing (MT) is proposed to alleviate oracle problem in software testing, which verifies software under testing (SUT) by checking whether inputs and outputs satisfy metamorphic relation (MR).MR, the constraint constructed from the propriety of SUT, plays a key role in MT and becomes focus in MT researching.Failure detecting ratio (FDR) is a popular measure for failure detecting ability of MR.However, FDR is the mean of failure detecting ratios of a MR applied on different mutants.This averaging covers some important properties of MR.In this paper, sensitivity of MR is defined, which is a multi-dimension information vector consisted of failure detecting ratios on all mutants.Sensitivity of MR reflects more fully characteristics of MR than FDR and allows more possibility in MT researching.One typical application of sensitivity of MR is the cluster analysis on MR set, in order to find some clues of the underlying relevant between the requirement of MR and its failure detecting ability.K-means algorithm, a classical cluster analysis algorithm, based on MR sensitivity is applied in the experiment.The experiment results show that the sensitivity of MR supports cluster analysis strongly and the analysis offers some useful knowledge.Sensitivity of MR will be a good method and essential rationale for MT researching.关键词：metamorphic testing;metamorphic relation;metamorphic relation sensitivity;cluster analysis algorithm165|527|1更新时间：2025-07-16
- 摘要：In order to improve the delay and area design of large-scale MPRM circuits, the multi-strategy discrete particle swarm optimization(MSDPSO)is proposed.In MSDPSO, the particles were divided into several teams with different strategy, and each team cooperated with others to promote the exploration and exploitation of the particle population.Meanwhile, the Gaussian adjustment was adopted to activate the worse individuals.Combined with MSDPSO and tabular technique, the best polarity of delay and area was searched for large-scale MPRM circuits.MCNC Benchmarks with PLA format are tested to verify the effectiveness of the MSDPSO, and the results show that MSDPSO has achieved an average saving of 8.46% and 38.73% on delay and area respectively in comparison with the DPSO.关键词：multi-strategy discrete particle swarm optimization(MSDPSO);MPRM circuits;delay and area optimization;polarity search188|489|4更新时间：2025-07-16
- 摘要：In hands-free telephones and teleconferencing systems, the echo path to be estimated by the adaptive filter is usually sparse.The improved proportionate normalized least-mean-square (IPNLMS) algorithm can increase the convergence rate of the adaptive filter when it is used to estimate sparse systems.However, the steady-state misalignment of the IPNLMS algorithm may suffer from much larger fluctuations than that of the normalized least-mean-square (NLMS) algorithm.To address this problem, a time-varying parameter IPNLMS (TV-IPNLMS) algorithm is proposed, which uses a sigmoid function to adjust the value of the time-varying parameter according to the ratio of the mean square error (MSE) to the power of the system noise.This time-varying parameter can reduce the proportionate gains of the IPNLMS algorithm when the adaptive filter arrives at steady state.Simulation results show that the time-varying parameter method can reduce the fluctuations of the steady-state misalignment of the IPNLMS algorithms.This algorithm can be used in the fields of echo cancellation, active noise control, and so on.关键词：hands-free telephone;teleconferencing system;proportionate adaptation;time-varying parameter;steady-state misalignment406|486|1更新时间：2025-07-16
- 摘要：The existing methods for interleaver estimation usually use hard-decision of the demodulator output sequence, their robustness against error bits is to be improved and some methods only aim at certain interleavers.Focusing on the random interleaver of Turbo codes, this paper presents an estimation algorithm which uses soft-decision.Firstly, the concept and calculation method of the average conformity of parity-check equation are given.Then, the permutation positions of the interleaver are estimated step by step, using the truth that the correct permutation position could maximize the average conformity of parity-check equation.Especially, the proposed algorithm still performs well in puncturing case.Results of simulation experiments show that our algorithm has better performance and relatively lower complexity, especially in low signal-to-noise ratio cases, compared to the existing relevant algorithms.关键词：Turbo-code interleaver;soft-decision;low signal-to-noise ratio;average conformity of parity-check equation112|620|14更新时间：2025-07-16
- 摘要：Probabilistic Graphical models bring together graph theory and probability theory in a single formalism, so the joint probabilistic distribution of variables can be represented using graph.In recent years, probabilistic graphical models have become the focus of the research in uncertainty inference, because of its bright prospect for the application.In this paper, we conclude the representation of probabilistic graphical models in recent years.Finally, a discussion of the future trend of probabilistic graphical models is given.关键词：probabilistic graphical models;continuous;inhomogeneous;Bayesian logic;Markov logic;non-parametric;matrix normal graphical model;Coupula function;mixed graphical model230|2032|3更新时间：2025-07-16
- 摘要：The calculation of travel time of city roads is an important issue in the domain of the intelligent transportation system research.License plate recognition data is one kind of monitoring data for vehicles running on urban roads, which has some new features, such as high volume, high velocity and spatio-temporal correlation.In order to achieve travel time calculations on massive license plate recognition data collection, we present the formal definition of travel time calculation based on license plate recognition data set, and propose a pipelined parallel computing model based on spatio-temporal data partition.Moreover, the implementation of the computing model is given based on a real-time MapReduce computing system.The corresponding experiments based on real license plate recognition data set show that, the computing performance on million-level data sets of our method can achieve three times increasing compared to traditional travel time calculation methods.Meanwhile our method is more suitable for fine-grained partition and large scale traffic network.关键词：travel time;spatio-temporal partition;parallel pipeline;real-time mapreduce;large-scale license plate recognition data227|569|2更新时间：2025-07-16
- 摘要：There exist limitations of local combinatorial explosion and only exponential distribution of spare nodes in Bayesian network(BN)-based dynamic fault tree(DFT) analysis method.First, an approach of mapping DFT into discrete-time BN is proposed in which a deterministic function instead of conditional probability tables is used to avoid local combinatorial explosion.Second, according to the failure mechanism and BN structure of spare door, we remove the limitation that the failure time of spare nodes in BN is only exponential distribution.Finally, an exact inference algorithm of DFT-based BN is presented and based on which the failure distribution of system and the importance measurement of components is calculated.Experimental results show that the proposed method can analyze and evaluate the probability characteristics of safety-critical systems effectively.关键词：dynamic fault tree;Bayesian network;quantitative analysis;safety-critical system304|659|11更新时间：2025-07-16
- 摘要：In the underwater sensor networks for underwater environment monitoring application, a network with sufficiently high coverage and connectivity rate is the guarantee of accomplishing the monitoring task.The NCPR algorithm, which is a underwater coverage preserving routing algorithm and oriented to improve the coverage performance, can effectively prolong the coverage time of the networks compared to the LEACH-Coverage-U algorithm.However, the connectivity performance of NCPR is defective, and in the algorithm there exist such a problem that the cluster heads close to the SINK node may die faster than other nodes because of the frequently forwarding of data.In this paper, we propose a distributed network unevenly layered coverage preserving routing algorithm (NULCPR) to improve the performance of NCPR.The network is established from SINK layer by layer, and the communication range of nodes increase with the layer departures form SINK.Each layer executes the NCPR algorithm independently to cluster the nodes in this layer, and the cluster node is used to establish a connective link to maintain the connectivity of the networks.The simulation results show that comparing with NCPR, NULCPR improves the connectivity and coverage rate of the networks, and makes the energy efficiency better.关键词：underwater sensor network;coverage preserving routing;network layering162|1007|6更新时间：2025-07-16
- 摘要：To solve the problem of contour noise and deformation in shape matching, a novel method based on common base triangle area for improving retrieval accuracy and computational efficiency is proposed.Firstly, a common base triangle area descriptor of each sample point is defined based on the area functions of the triangles formed by the other sample points and its two neighbor points.Then the descriptor is local smoothed to keep more compact and robust.Secondly, a match cost matrix is obtained by computing the common base triangle area descriptors of all the sample points on two shapes.Finally, the distance between two shapes is measured based on the match cost matrix by DP algorithm.The experimental results of MPEG-7, Kimia and the articulation shape database indicate that this method is robust to the contour deformation, and the computational efficiency and the retrieval accuracy are all essentially improved.关键词：common base triangle;local smoothing;dynamic programming;mixed retrieval;shape matching216|406|0更新时间：2025-07-16
- 摘要：Stokes parameter is the intensity dimension to describe polarized wave.Stokes parameter is widely used in electromagnetism measure, synthetic aperture and radiometer.The digital method given in the paper has the characters of high-bandwidth and high-stability.The measure error contributed by digital sampling for Stokes parameter solution is analyzed in detail in the paper.The brightness temperature quantization error under auto-correlation is proved to be less than 1*10-5K in application with 3 bits quantization.Further the paper gives the system sensitivity, analyzes the brightness temperature error generated by the digital quantization.When quantization is above 3 bits, the digital system sensitivity can achieve 95% of ideal analog system.The theory foundation of digitization solution is given to prove its feasibility for different demand in different device.关键词：Stokes parameter;correlation;digital sample;quantization error129|423|0更新时间：2025-07-16
- 摘要：A simple method, based on higher-order cumulants, is proposed for the recognition of Orthogonal Space-time Block Code (STBC).Considering the impact of channel, we propose a method of signals whitening without estimating the channel state information.This method eliminates the channel interference for the recognition.It not only reduces the complexity of the algorithm, but also improves recognition probability ratio of Orthogonal STBC in low SNR.We use higher-order cumulants (of order greater than 2) to eliminate the impact of noise.We analyze the two fourth-order cumulants, and select the more suitable fourth-order cumulants as Characteristic parameters for the recognition.Simulation results show that the proposed method for blind recognition of Orthogonal STBC has good performance.关键词：space-time block code(STBC);higher-order cumulants;signal classification159|440|4更新时间：2025-07-16
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