最新刊期
卷 46 ， 期 7 ， 2018
- 摘要：Inspired by the correntropy,a robust DOA (direction-of-arrival) method based on sparse representation for impulsive noise was proposed.To recover the joint-sparse signal from multiple measurement vectors,a normalized iterative hard thresholding based optimization algorithm was designed.The optimal step size of the algorithm was discussed and the convergence was proved.The simulation results demonstrate that the proposed method could realize the DOA estimation for multiple sources,and it is superior to existing methods in terms of success rate and estimation accuracy.关键词：DOA estimation;impulsive noise;sparse representation;correntropy291|384|6更新时间：2025-07-16
- 摘要：Blind recognition of convolutional codes is the basis for recognition of certain high performance codes including concatenated and Turbo Code.It requires that the recognition methods for convolutional codes should have strong robustness against channel noise.The key to such purpose is to make use of the received soft information.Firstly,this paper gives a probabilistic analysis about the reason why the existing methods using soft information performs no better than the method based on hard information.The reason is that the candidate solution vectors of low Hamming weights seriously deteriorate the correct recognition probability.Then,a solution based on least-square cost function is proposed for this problem.Theoretical analysis proves that the impact of low Hamming weights can be effectively reduced.Finally,the theoretical results are verified by simulation experiments.Both the theory and the simulations show that,for blind recognition of convolutional codes,the proposed method improves the robustness against noise by about 1dB.关键词：blind recognition of codes;convolutional code;Walsh-Hadamard Transform;log-likelihood ratio (LLR);least square253|270|11更新时间：2025-07-16
- 摘要：In the context of M×N user multiple-input multiple-output (MIMO) X network,the different types of channel state information at the transmitters (CSIT) have impacts on the sum of degrees of freedom (sum-DoF).To approximate to the sum-DoF outer bounds,we propose a multiphase distributed space-time interference alignment (DSTIA) scheme for the MIMO X network with symmetric antenna configurations.We derive the closed-form solution of precoding matrix based on hybrid CSIT (i.e.,outdated and current CSIT) with distributed characteristics,while revealing the impact on how the CSI feedback delay,as well as the number of transmitters/receivers and the number of antennas affect the sum-DoF of the MIMO X network.Theoretical and Analytical results show that,with distributed hybrid CSIT,DSTIA scheme can achieve better sum-DoFs by eliminating inter-user interference perfectly,as well as tightening DoF gap and improving the achievable rates of system.关键词：degree of freedom;distributed hybrid CSIT;space-time interference alignment;precoding202|178|1更新时间：2025-07-16
- 摘要：When using the estimator for the extended object tracking,the algorithm accuracy is affected by the choice of the system evolution model.In this paper,we propose to take the extension information directly as the class-based information of the extended object,where each class determines the relevant motion models.Then we propose a joint tracking and classification algorithm based on the Multiple Model (MM) Gaussian Inverse Wishart Probability Hypothesis Density (GIW-PHD) filter.Simulation results demonstrated the efficiency of the proposed algorithm,compared with the performance of the GIW-PHD and MM-GIW-PHD filtering methods.关键词：extended objects;extension information;class-based information;Gaussian Inverse Wishart Probability Hypothesis Density (GIW-PHD);joint tracking and classification240|217|4更新时间：2025-07-16
- 摘要：Model-based diagnosis problem has been attracting much attention in the field of artificial intelligence.It is an important technique for solving model-based diagnosis problem by converting diagnosis problem to SAT.Based on the research of LLBRS-Tree,this paper proposes an ACDIAG method.Firstly,the circuit blocking method is used to block the circuit via circuit structure so as to downscale circuit.Then,minimal block diagnoses are acquired on the abstract circuit after blocking via LLBRS-Tree.Secondly,diagnosis extending method is given to extend minimal block diagnoses to obtain other diagnoses directly via circuit structure.It avoids the drawback that extending diagnoses need to restore the abstract circuit.关键词：model-based diagnosis;SAT problem;enumeration tree;abstract2246|204|4更新时间：2025-07-16
- 摘要：Software bug issues are inevitable in software development and maintenance.However,there are no corresponding relationships between bugs and commits in software repository.Moreover,with the increasing amount of bug reports and commit information,bug search in the software repository becomes more difficult and costly.In this paper,we propose an exploratory search approach to search bug issues based on knowledge graph.By building the bug knowledge graph of bug reports,commits and related developers (such as bug reporters,committers and so on) and combining with the idea of exploratory search,our approach can not only help software developers search bug issues accurately,but also provide the relevant information to explore bug issues,thus software developers can understand and resolve bug issues more effectively.关键词：bug report;commit;knowledge graph;exploratory search514|457|4更新时间：2025-07-16
- 摘要：Under the condition of information technology,there is a high degree of uncertainty in the combat environment of manned/unmanned aerial vehicle formation;so how to evaluate the threat of targets quickly and efficiently becomes an urgent problem to be solved.In the framework of intuitionistic fuzzy sets,researching the satiation that decision makers with preference information on alternatives,the target attribute value is interval number and weight is unknown,a threat assessment method with unknown attribute weight optimized by QABC (Quantum Artificial Bee Colony) optimization algorithm is proposed based on IFMADM (Intuitionistic Fuzzy Multi-Attribute Decision Making).Firstly,preference model is constructed;secondly,the optimization model of optimal attribute weights is established considering the objective optimization taxis and preference information of decision maker synthetically,making attribute weights more reasonably reflect the actual situation by QABC optimization algorithm.Finally,the effectiveness of the proposed method is demonstrated by an example of formation threat to ground attack.关键词：manned/unmanned aerial vehicle formation;IFMADM;air-to-ground attack;threat assessment;QABC227|172|10更新时间：2025-07-16
- 摘要：In this paper,the face image is divided into two separated parts:aging effect feature part and identity related feature part.The identity dictionary and the age dictionary are introduced to encode the two feature parts into two separated feature spaces.To make sure the learned dictionaries are discriminative for different classes,the reconstruction error and label matrices constraints are added in the training.Face features can be encoded into identity and age space with the learned identity and age dictionaries.The identity space can be used for further classification.Extensive experiments are conducted on the MORPH and FGNET dataset,illustrating a great improvement over the state-of-the-arts.关键词：face recognition;age invariance;dictionary decomposition;space learning307|331|5更新时间：2025-07-16
- 摘要：This paper presents an efficient and effective approach based on local shape structure classification for detecting media-adventitia border in intravascular ultrasound (IVUS) images.First,the category of local shape structures is found by using k-means clustering method.Second,patches from IVUS images indexed by the category are extracted by two kinds of features including integral channel and self-similarities features,and therefore a random decision forest model is constructed.Finally,the key points of testing IVUS images are detected using the trained classification model.Then with the help of curve fitting methods,detection of media-adventitia border is acquired.Experimental results demonstrate that the proposed algorithm effectively relieves the difficulties of interference factors such as plaques,artifacts and side vessel,and more accurately recognizes the key points of target border compared with existing algorithms,detects the whole target border successfully.The Jaccard Measure (JM) of media-adventitia border detected by the algorithm is 88.9%,Percentage of Area Difference (PAD) and Hausdorff Distance (HD) measures are reduced by 19.1% and 9.7% respectively.关键词：medical image analysis;machine learning;random decision forest;k-means clustering;local shape structure;intravascular ultrasound;media-adventitia border detection320|387|3更新时间：2025-07-16
- 摘要：It's far less effective for the stateless accelerator to accelerate the stateful network function.In order to solve the problem,this paper presents a programmable hardware-based stateful network function acceleration architecture which is called Stateful Function Processing Acceleration (SFPA) architecture.Providing the Stateful Processing Unit (SPU) to the data plane,SFPA can offload the data processing task to the data plane.In addition,SFPA can allocate the acceleration resources to multiple VNFs independently,decrease hardware cost and improve the flexibility of the acceleration architecture with the resource allocation optimization algorithm.Results of the experiments which are based on the NetFPGA-10G platform show that the throughput of VNF is 2.9 times faster than that of DPDK,and 1.7 times faster than that of stateless hardware accelerator in the SFPA.The optimal rate of resource allocation optimization algorithm is up to 41.9%.关键词：network function virtualization;programmable hardware;stateful processing;hardware acceleration;resource allocation optimization241|288|0更新时间：2025-07-16
- 摘要：Coflow completion time minimization is one of the challenges of traffic management in data center networks.Inspired by the newest research progress in deep reinforcement learning,which is one direction of artificial intelligence,this paper proposes a novel coflow scheduling mechanism.It translates the coflow scheduling problem with bandwidth constraint into a continuous learning process.By learning the previous decisions,the best scheduling is obtained.By introducing back filling and limited multiplexing mechanisms,the system is work-conserving and starvation-free.Simulation results show that,under different network load,compared with other scheduling mechanisms,the average coflow completion time is reduced.Especially when the network load is heavy,the proposed mechanism achieves about 50% performance improvement than the state-of-the-art scheduling mechanism.关键词：data center network;coflow;flow scheduling301|672|1更新时间：2025-07-16
- 摘要：In this paper,for the problem that the cables in aircraft power system are complex,numerous and hard to detect,the method based on chaotic spread spectrum sequence for synchronous online diagnosis of complex cable system is proposed.The proposed method can solve the limitation of the cables' number that can be diagnosed synchronously in spread spectrum time domain reflectometry (SSTDR).The model of chaotic spread spectrum sequence is established,and the research shows that its pointed autocorrelation characteristic can be applied in single cable fault diagnosis,and its good cross-correlation characteristic can be applied in multiple cable faults diagnosis.With the large number of chaotic sequence,the proposed method can be extended to online diagnosis of multiple cable faults.The experimental results show that the method of chaotic sequence can effectively realize the synchronous diagnosis of multiple cable faults,with the location error within 20cm and the detection rate above 90%.关键词：chaotic;number of sequence;multiple cables;SSTDR (spread spectrum time domain reflectometry);autocorrelation;cross-correlation205|219|2更新时间：2025-07-16
- 摘要：To settle the variability of steering vector with frequency in direction of arrival (DOA) estimation for wideband signals,a new algorithm is proposed.First,the array delays of the signal in search direction are compensated to have the same characteristics as that in normal direction.Meanwhile,the signals in other directions are processed as noise.Then,the value of spatial spectrum in search direction is measured by the computed orthogonality of subspaces.Finally,to improve the computational efficiency,a fast algorithm is used in the new algorithm.Because the delay of filter can not be changed arbitrarily,a frequency domain method is adopted to compensate the array delays with compensation matrix.The new algorithm doesn't require the number of sources or the initial values of DOAs.More than this,the results of simulation experiments show that it performs better than existing algorithms in terms of the resolution and the estimation error when the received signals are incoherent and their power spectral distributions are smooth.关键词：direction of arrival;wideband signal;direction focusing;frequency domain method;delay compensation162|220|4更新时间：2025-07-16
- 摘要：The relationship between the nonlinear coefficient and parameter values of Nakagami distribution from the envelopes of fundamental and second harmonic signals are investigated to obtain more accurate nonlinear quantitative characteristics of tissue.The envelopes of fundamental and second harmonic signals are separated from the whole echoed RF signals using Butterworth high-pass filter.Then the Nakagami distribution parameters of the envelope signals are calculated and compared.The simulation results show that for different values of the nonlinear coefficients,the values of distribution parameters of the fundamental envelope signals are aliasing.On the contrary,the parameter values of second harmonic are mutually separating,especially for the nonlinear coefficients ranged from 3 to 6.In vitro experiments,compared with fat tissue,the relative differences of Nakagami parameter ω and μ of the fundamental envelope signals for liver and brain tissue are 7.3%,0.03% and 2.0%,4.3%,respectively;however the relative differences of 2nd harmonic envelope signals are 8.3%,19.4% and 7.0%,34.0%,respectively.The results of vitro experiments verify the effectiveness and correctness of the simulation results.In conclusion,the parameter values of Nakagami distribution for the second harmonic envelope signals from different degrees of nonlinearity in tissue are significantly different.According to this,we can quantitatively analyze the nonlinear characteristics of biological tissue.关键词：Nakagami distribution;nonlinearity;ultrasonic harmonic signal;tissue characteristics142|381|2更新时间：2025-07-16
- 摘要：In order to address the defects of poor error tolerance and large amount of calculation in current RSC encoder recognition algorithms,a new algorithm based on discrete PSO is proposed.Firstly,because of the special structure of RSC codes,the recognized model based on the discrete PSO algorithm is built and the fitness of algorithm as well as terminal threshold are deduced.Then,the detailed steps and process to recognize the RSC codes are put forward according to the identification model to overcome the defects in current algorithms.The simulation results show that the algorithm has perfect performance when the number of memories is small.The correct ratio of recognition can reach 90% at different number of memories when the rate of bit error is 0.05,some of which can even reach 100%.Besides,the calculation of algorithm increases linearly with the number of memories and branches of codes,which is reduced greatly compared with the Walsh-Hadamard.关键词：recursive systematice convolutional codes;the discrete particle swarm optimization;the function of fitness;terminal threshold;recognition99|182|2更新时间：2025-07-16
- 摘要：For the lack of the single threshold denoising method of synchrosqueezed wavelet transform(SST),an improved denoising method for chaotic signal is proposed based on SST hierarchical threshold.Firstly,according to the distribution models of SST decomposition coefficients of the signal and the noise,the formula of mean square error of SST chaotic signal denoising is derived,which contains the threshold coefficients of amplitude.Then,the optimal threshold coefficients of amplitude is calculated based on the minimum mean square error criterion.Finally,the optimal hierarchical thresholds of SST chaotic denoising is determined according to the optimal threshold coefficients and the standard deviation of the noise.In the experiments,the denoising performance of the proposed method is tested by using the simulated chaotic signals and the measured monthly sunspot signals.The experimental results show that the proposed method can filter the noise of chaotic signal better,and the chaotic properties of the originals can be largely recovered.The proposed method can obtain better performance in the chaotic signal denoising than the classical wavelet transform threshold method and the EEMD denoising method.关键词：synchrosqueezed wavelet transform;de-noising;chaotic signal;hierarchical threshold218|159|3更新时间：2025-07-16
- 摘要：In elastic optical inter-datacenter networks,for addressing the problems of lower spectrum utilization and high bandwidth blocking probability,an algorithm based on tree-splitting and shared lightpath-merged for manycast is proposed.The new branches having minimum influence on light-tree's maximal length and modulation level are selected to insert into the spanning light tree,making the cost of spectrum consumption minimal.For reducing bandwidth blocking probability,the light tree is split into several sub-light trees with higher modulation when bandwidth is insufficient for the manycast.When the adequate spectrum bandwidth is found,the scheme based on link-sharing degree is designed to merge the split sub-light trees on a light tree for reducing spectrum consumption.The simulation results show the proposed algorithm can get the lowest bandwidth blocking probability and highest spectrum utilization.关键词：elastic optical networks;manycast;tree-splitting;bandwidth blocking probability;spectrum utilization144|138|2更新时间：2025-07-16
- 摘要：To improve the performance of radar emitter recognition under low signal-to-noise ratio,a method that extracts features from ambiguity function with derivative constraint on smoothing is proposed.A mathematical model to obtain the max energy angle based on rounding function and coordinate transformation is set,greatly reducing processing complexity.An algorithm picking the waveform of max energy slice is also presented referring to derivative constraint on smoothing.It depends on none specific signal and noise models.The algorithm is transferred into Second-order Cone Programming (SOCP) for solving and it weakens the influence caused by noise upon ambiguity function waveform features to a great extent.According to the validity index,values of the regularization parameter in objective function and the norm parameter in symmetrical Holder coefficient are determined.Finally,fuzzy c-means clustering is implemented for classification and recognition of feature vectors extracted from emitter signals.Simulation results indicate that the method presented in the paper gains higher correct recognition rate.关键词：radar signal recognition;ambiguity function;derivative constraint;second order cone programming (SOCP);symmetrical Holder coefficient187|163|10更新时间：2025-07-16
- 摘要：The adjustment of parameters in particle swarm optimization (PSO) has attracted the attention of many researchers.In the paper,an alternative technology,a non-parameter PSO algorithm with fast convergence speed is proposed.A multi-crossover operation and an exemplar-based learning strategy are combined with the proposed algorithm.According to the first-and second-order stability analyses conducted for the present study,the particle positions are expected to converge at a fixed point in the search space,and the variance of the particle positions converge at zero.In our experiments,we compared the proposed algorithm with 7 other advanced PSO algorithms using 24 widely used benchmark functions.The experimental results indicate that the proposed algorithm yields better solution accuracy than the other PSO algorithms.In particular,the proposed algorithm outperforms the other PSO approaches significantly in terms of the convergence speed.关键词：particle swarm optimization;crossover operation;parameter selection;stability analysis178|215|2更新时间：2025-07-16
- 摘要：An anonymous identity-based Hash proof system from static assumptions on composite order bilinear groups is constructed.To achieve the anonymity,random elements of a new subgroup are added to the public parameters and ciphertexts.The desired security properties are proved by dual system encryption technology.Applying the anonymous identity-based Hash proof system to the leakage-resilient cryptography,a leakage-resilient anonymous identity-based encryption scheme with full security and a leakage-resilient anonymous identity-based encryption scheme with CCA-security are derived from it respectively.关键词：identity-based Hash proof system;leakage-resilience;anonymous identity-based encryption;full security;composite order bilinear groups;dual system encryption153|184|0更新时间：2025-07-16
- 摘要：An energy functional based on variational framework and the phase-transition theory is presented for saliency detection.We describe a Sobolev gradient to find minima of the proposed functional,and then a temporal evolution system for computer visual selection is produced.The process of saliency extraction is a dynamical competition between salient and non-salient component.Comparing the classical L2 gradient,we find that the Sobolev metric induces favorable regularity properties in their gradient flow.We demonstrate the consistency between the dynamical behavior of the evolution system and visual selection,which is very important for human to exploit new mechanism of saliency detection.Experimental results on various images show that our model achieves better suppression of the information in background,while achieving higher detection precision of the object,texture,hair,etc,which is important in terms of human visual perception.关键词：visual attention;saliency detection;phase field method;variational model;Sobolev gradient168|187|1更新时间：2025-07-16
- 摘要：Specific to the anaphora phenomenon of Uyghur personal pronouns,a deep learning mechanism of Bi-LSTM (Bi-directional long short term memory) network is proposed,which is based on the deep semantic information to resolve anaphora resolution problem in Uyghur personal pronouns.Firstly,make the word embedding which contain semantic and syntactic information as the input of Bi-LSTM,to excavate the implicit semantic features of Uyghur.Secondly,explore the anaphora phenomenon in Uyghur and extract 24 hand-crafted features.Then,use multilayer perception(MLP)to concatenate hand-crafted features and context semantic features.Finally,two types of features are used to train the softmax classifier to complete the task.The experimental results show that,on the basis of full utilization of the advantages of two types of features,the F1 value of anaphora resolution is 76.86%.It is proved that Bi-LSTM is more capable of mining implicit context semantic information than LSTM、SVM as well as ANN,and the introduction of hand-crafted features can effectively improve the performance.关键词：anaphora resolution;Bi-LSTM;word embedding;deep learning;Uyghur;natural language processing281|203|2更新时间：2025-07-16
- 摘要：This paper presents an image segmentation fuzzy model and algorithm based on multi-dictionary learning.In the proposed model the conformity within the segmented regions and the regularization of the boundary are considered by combining multi-dictionary learning and fuzzy method.On one hand,image patches are reconstructed by using the block means within the segmented regions and a structured dictionary with class labels.The class-specific reconstruction residual and the l2 regularization term measure the conformity within the segmented regions.This measurement can describe intensity information and texture pattern for different regions of images.On the other hand,the wavelet sparsity regularization is employed to preserve geometric shape of the segmented regions.Based on the alternating direction method of multipliers and dictionary learning method,we design a fast alternative iteration algorithm to solve the proposed model.In the proposed algorithm each step except wavelet shrinkage is a closed form.Hence it is easy to use.Numerical experiments are presented to demonstrate the efficient performance of the proposed algorithm.关键词：image segmentation;dictionary learning;variational model;regularization method105|256|5更新时间：2025-07-16
- 摘要：A facial expression recognition method named SS-PLDA is proposed based on Sparse Feature Selection and Probabilistic Linear Discriminant Analysis.The SS-PLDA method contains two steps:1) pick out the most discriminative regions for facial expressions and use these regions to construct a complete facial features set;2) apply Probabilistic Linear Discriminant Analysis Method to separate the useful expression signals from other disturbance information.Therefore,a subspace which only contains expression information is learnt and the expression recognition task is implemented in this subspace.Experimental results on Cohn-Kanade(CK+) database and JAFFE database show that the complete facial features set can improve the performance,and the proposed method outperform the state-of-art ones.关键词：facial expression recognition;sparse;feature selection;subspace learning141|252|5更新时间：2025-07-16
- 摘要：Pedestrian detection is widely applied in driver assistance systems and video surveillance fields,while proposal generation is a significant preliminary work for pedestrian recognition and tracking.This paper proposes a method for fast online proposal generation using Local Mixture Probability (LMP) model.Poisson model and Gaussian model are separately established for online learning location and scale of pedestrians after region-dependent segmentation according to local similarity.Based on learning and updating models,both the probability of pedestrians occurrence and the probability distribution of the scale in specific regions can be obtained,which provides bases for pedestrian proposal generation and avoids searching blindness.Experiments on Caltech Pedestrian dataset show that LMP can achieve higher recall by fewer pedestrian detection proposals.关键词：machine vision;pedestrian detection;LMP model;proposal generation211|255|0更新时间：2025-07-16
- 摘要：Based on Spatial Pyramid Matching method,aiming at the insufficient utilization of spatial information,firstly,local position feature is extracted by computing relative position distribution of each dictionary vector in image.Then,global contour feature is generated through Nonsubsampled Contourlet Transform and Linear Discriminant Analysis.Finally,Spatial information is enhanced by combining local position feature with global contour feature,which consequently improves the accuracy of scene and object classification.Extensive experiments are performed on Caltech 101,MSRC and 15 Scene datasets respectively.The experimental results show that the proposed method further utilizes the spatial information,and thus improves the accuracy of image classification.关键词：image classification;bag of words;local position feature;nonsubsampled contourlet transform;global contour feature220|225|2更新时间：2025-07-16
- 摘要：Long sleeping time of nodes in a low-duty-cycle sensor network will increase data enquiry latency.How to schedule wakeup time of different nodes in the network to minimize the latency is a combinatorial optimization problem.A distributed circular pipeline scheduling algorithm is proposed,by which enquiry data can be transmitted without long wait.Analyses show that the algorithm achieves not only lower latency,but also longer network lifetime.关键词：low-duty-cycle sensor networks;distributed algorithm;circular pipeline work scheduling;data enquiry142|137|1更新时间：2025-07-16
- 摘要：In order to overcome the limitation of the traditional method of ceramic identification,an ultrasonic identification method based on the weighted Euclidean distance is proposed.Three ceramic boxes with the same outline dimensions as experimental samples,the relationships between ultrasonic wave length and the particle size of ceramic are analyzed according to cross-section SEM photographs of the ceramic,the weighted Euclidean distances between standard sample and other samples are calculated by extracting 10MHz ultrasonic backscattering signals,and compared to the self-weighted Euclidean distance of the standard sample.The calculated results show that the weighted Euclidean distance between different samples is different.Using the weighted Euclidean distance of the backscatter signal,the ceramic sample can be identified quickly and accurately.关键词：ultrasonic;particle size;backscattering signal;weighted Euclidean distance105|139|13更新时间：2025-07-16
- 摘要：In the field of brain cognitive science,more researches begin to focus on the interdependence between different leads of EEG signals to study the overall cognitive function of the brain.The Phase Lag Index (PLI) can reduce the errors effectively caused by the volume conduction and has been widely adopted,however brain network research method based on graph theory was scarcely reported in lie detection field.In this study,the network topology of the EEG signals from 30 (innocent and guilty) subjects are analyzed.The network parameters are used as the discriminant indicators,and the experimental data are classified by using support vector machine.The study finds that the small world indexes have pretty significant statistical differences between two groups.Also,the classification system gets a higher lie-detection accuracy,which proves the validity of polygraph using PLI method and graph theory analysis.关键词：PLI;lie detection;EEG signals;functional network270|315|3更新时间：2025-07-16
- 摘要：Adaptive transmission technology can effectively inhibit channel fading caused by atmospheric turbulence in wireless optical communications.Under the predefined bit error rate and received signal-to-noise ratio requirement,this paper researched a wireless optical adaptive transmission system due to changing the modulation order through the instantaneous nature of turbulence.Malaga distribution turbulence model is used to describe the distribution of the Gamma-Gamma,Lognormal and K distribution turbulence channel separately,and the related parameters setting methods are given.Analytical expressions of spectrum efficiency,average bit error rate and outage probability under Malaga channel are derived in the adaptive subcarrier M-ary differential phase shift keying (MDPSK) system.Closed form expressions are also derived based MeijerG function.With the comparison between the performance of adaptive modulation and non-adaptive modulation system,the results show that the adaptive system can acquire lower BER performance under the same telecom noise ratio,and also improve the spectrum efficiency without additional transmission power or sacrifice bit error rate.关键词：wireless optical communication;Malaga turbulence distribution;subcarrier modulation;adaptive transmission;average bit error;spectrum efficiency220|219|6更新时间：2025-07-16
- 摘要：Big datatransaction is a key point of promoting data circulation and data value.It is important for building efficient and robust trading platform to optimize process of big datatransaction.Big data transaction is a typical complex process model,which makes the traditional model repair method not able to effectively discoverand reduce the deviation between process execution and process rules.This paper proposes an approach of repairing big datatransaction model based on deviation reduction.With the help of the reachable marking graph,the approach discovers the deviation between the event log and the process model found,reduces the deviation between the event log and the model,and gets the repaired model based on the effective deviation.At the end of this paper,the proposed approach is used in the Tianyuan big data platform to verify the effectiveness.By comparison experiments of those repair methods based on model alignment and the iteration of the effect of repairing is evaluated from the aspects of fitness,precision,simplicity and time complexity.The evaluation shows that the proposed approach has an advantage over existing methods.关键词：big data transaction;model repair;model evaluation;deviation reduction179|186|4更新时间：2025-07-16
- 摘要：Focusing on the issues of rating prediction such as subjectivity of user rating and inaccurate prediction caused by rating sparsity,a rating prediction method is proposed by introducing the characteristics of social recommendation.Firstly,aiming at the subjective of user rating,we introduce and optimize the cloud model theory.Then,a method to generate rating standard by synthetical cloud model and transform user rating under the standard is proposed.Secondly,to deal the problem of inaccurate score prediction caused by data sparseness,data dimension reduction and target user location are achieved by introducing membership degree.And taking into account that user rating can be affected by their social relationship,we try to learn two rating prediction models by respectively using social relationships and similar groups.Finally,the rating value is obtained by using Gauss transform to combine the two prediction models.Experimental results show that our method not only overcomes subjectivity of user rating,but also alleviates the poor accuracy caused by rating sparsity problem in traditional rating prediction methods.关键词：social network;recommendation system;rating prediction;cloud model363|359|2更新时间：2025-07-16
- 摘要：In this note,we study some results on a class of cyclic codes over Z4×(F2+uF2).We give the definition of this class of cyclic codes over Z4×(F2+uF2) first.Then we determine the generators and the minimum generating sets of a type of cyclic codes.Finally,some binary nonlinear codes are constructed by this type of cyclic codes.关键词：cyclic codes;generators;minimum generating sets;binary nonlinear codes162|166|1更新时间：2025-07-16
- 摘要：Quantum-dot cellular automata (QCA),a burgeoning technology at nano-scale range,has the potential to take the important place of CMOS technology to be the next IC technique.In this paper,three existing schemes of QCA full adders (FAs) are analyzed in detail using probabilistic transfer matrix (PTM) to find out the most robust one.Three types of n-bit carry flow adders connected serially by these three FAs respectively are also analyzed in terms of complexity,irreversible power dissipation and cost to find out the corresponding FA scheme with best performance.It turns out that MR Azghadi FA always performs well by these two means.With MR Azghadi FA layout,a new logical gate and coplanar QCA FA are then proposed.Analysis and comparison with previous coplanar FAs demonstrate that the proposed FA has a great optimization with respect to area,cell count and power dissipation and also has favorable scalability.关键词：quantum-dot cellular automata;full adder;reliability;probabilistic transfer matrix168|244|0更新时间：2025-07-16
- 摘要：In this paper,a novel SOI LDMOS with step width drift region using high-k dielectric is proposed and investigated by a 3D simulator named DAVINCI.The drift region of new device is divided into several regions with different width using the high-k dielectric.First,new additional electric field peaks are formed at the steps,which enhances the breakdown voltage.Second,the high-k dielectric modulates the potential and electric field distributions to further improve the breakdown voltage,and allows keeping a higher drift doping concentration to reduce the specific on-resistance.Compared with the conventional device,a 42% increase in the breakdown voltage and a 37.5% decrease in the specific on-resistance are obtained in the new SOI LDMOS.The FOM of new device is 3.2 times of the conventional device.关键词：step width;high-k dielectric;breakdown voltage;on-resistance;SOI200|150|3更新时间：2025-07-16
- 摘要：Beta mixture model (BMM) is an important non-Gaussian probability model,which has been widely used in statistical analysis of the bounded data.It is hard to perform parameter estimation for BMM,due to its complex function format.An efficient variational Bayesian learning method has been proposed to deal with this problem.With the variational distribution and by iteratively maximizing the lower bound of the original variational object function,the approximating distribution which is the closest to the true Bayesian posterior distribution is obtained.Both synthetic and real data are experimented to demonstrate the effectiveness and the merits of the proposed approach.关键词：beta distribution;Bayesian estimation;model selection;variational inference;object categorization190|309|0更新时间：2025-07-16
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