最新刊期
卷 34 ， 期 10 ， 2006
- 摘要：Wireless multimedia network will be on the basis of the packet technology,support the transmission of multi-traffic,and accordingly cause the great challenge for the QoS guarantee.The operators will define the QoS of traffic according to their requirements,and provide the traffic with different QoS requirements.Call admission control will aim at the packet traffic,guarantee the different QoS requirements,and maximize the system utilization.In this paper,a novel QoS based CAC policy for the asymmetric traffic in symmetrical CDMA systems is proposed.The operators can define the priorities of all kinds of traffic according to their demands.And as the presence of asymmetric traffic in the wireless network,the channel resource should be assigned fairly and reasonably according to the working states.The free resource will be assigned to the traffic with higher priority.The simulation results show that this policy can guarantee the QoS of different traffic efficiently,and improve the resource utility significantly.关键词：call admission control;symmetrical system;asymmetrical traffic;QoS;residual capacity2|577|4更新时间：2025-07-16
- 摘要：The work focuses on filtering users' interested contents in Chinese web pages.Two-stage filtering method based on UCL is presented.SCU is brought forward to express the information of Medium Space.SVSM is introduced to filtrate cursorily web pages,and then contents of these pages are understood by virtue of some elaborate semantic characteristics,so the web pages which users are interested in can be extracted.At the same time,the users’ interested changes are tracked dynamically according to the reading actions,and the interesting ontological profile is submitted,then the measure of interestingness is analyzed and calculated.Laboratory simulations demonstrate the arithmetic feasibility and validity.关键词：UCL;information filtering;SCU;SVSM;interesting ontological profile2|1533|2更新时间：2025-07-16
- 摘要：A generalized multi-antenna channel model and generating process are proposed for the broadband MIMO channel.By introducing the Kronecker product into the frequency domain and employing the concept of scattering fading weight factor,an outdoor broadband MIMO scattering-distribution model is derived.With simplification,this model can also be applied to indoor scenario.Simulation results show that this model well describes the LoS,NLoS,indoor,and outdoor scattering properties of broadband MIMO channel as well as the keyhole effect.关键词：MIMO;channel model;broadband channel;Kronecker product2|2037|4更新时间：2025-07-16
- 摘要：To effectively combine ad hoc networks with multiple input multiple output (MIMO),distributed topology-transparent schedule for time division multiple access (TDMA) protocol with MIMO links in multihop ad hoc networks is proposed.By Galois Radio Network Design (GRAND),the protocol assigns each node slots in each frame and need not know the whole network topology information,thus the overhead to collect topology information is greatly reduced.By reservation each node simultaneously transmits all data streams in the MIMO link in its assigned interference-free slots and utilizes its shared slots with other nodes to transmit a part of all data streams in the MIMO link to resolve collisions.The guaranteed throughput and optimal frame length are also derived.Results show that the network throughput will be improved greatly by dynamically allocating MIMO transmission capacity and its anti-interference ability.关键词：time division multiple access(TDMA);multiple input multiple output(MIMO);multihop ad hoc networks;topology-transparent2|1259|4更新时间：2025-07-16
- 摘要：According to the DiffServ mechanism in IETF,we present an integrated pricing architecture consisted of access price,usage price and congestion price,which lead to an effective and real-time pricing method.With the method,different charging rates are applied to different service levels,and token-based congestion pricing policy works when sending rate exceeds what is specified in SLA contract,which urges customers to select suitable service level.Furthermore,customers can alternate service levels to maximize utilities when their burst sending rates lead to raised charging rates.Besides those,ISP can interfere to help distribute customers among different levels.Such an integrated pricing mechanism in which supply and demand dominate,and plan assists guarantees the network to be utilized effectively.Simulation verifies the equitableness,effectiveness and flexibility.关键词：diffServ;real-time charging;service-level charging;congestion charging;user utility;traffic shaping2|885|1更新时间：2025-07-16
- 摘要：A novel scheduling scheme,called Two-Dimensional Priority Real-Time Scheduling (TDPRTS),is proposed for open systems.This scheme not only sets task priority,but also sets scheduling policy priority.The execution order of task is determined by both task priority and its scheduling policy priority.It can not only separate scheduling mechanism from scheduling policy but also improves the performance.This scheme also introduces the CPU bandwidth control so as to realize different real time systems with different goals,such as hard,soft and hybrid real time systems.It also simplifies the schedulability analysis of the tasks,and it can provide the services with different QoS to the users with different rights and levels.This mechanism has high efficiency and high open degree.It can be used to extensive fields and has high extensibility.关键词：open systems;two-dimensional priority;real-time scheduling2|743|5更新时间：2025-07-16
- 摘要：Price time Petri net is an emerging tool to analyze time and cost attributes of web service process and workflow model.Correspondingly the priced timed automata is a mature tool.We propose a method of state space computing which can compute the state space of a price time Petri net as a priced timed automata.The idea of this method is to add a price attribute in extended state class.Furthermore,we prove that the generated priced timed automata is bisimilar to the initial price time Petri net.关键词：price time Petri net;priced timed automata;state space computing2|969|3更新时间：2025-07-16
- 摘要：A low complexity dynamic resource allocation algorithm for multiuser multiband OFDM (MB-OFDM) system is proposed to minimize the total transmitting power while satisfying all users’ data rate (DR) requests.The complexity is reduced by means of converting the convex optimization problem to a linear programming (LP) one,introducing the concept of cluster and other ways as finding better feasible initial solutions of the LP problem.It is shown that this algorithm only has very limited performance loss compared with current methods by numerical methods,in which the effects of cluster size and user number are also analyzed.关键词：ultra wideband;multiband;dynamic resource allocation;cluster2|896|0更新时间：2025-07-16
- 摘要：Many problems in cryptology and information security fields are eventually converted to time-consuming computations which usually need to be completed over heterogeneous and geographically distributed computers.The analysis,design and application of a cryptographic algorithm usually depend on its concrete computing settings;different algorithms and different implementations of an algorithm need different computing environments.In this paper,the targets and features of different cryptographic computations are firstly analyzed according to their computing requirements;the corresponding computing modes are put forward;and a general purpose cryptographic computing model on grid is given.The task dividing policy,resource allocation and load balance for the model are then discussed.The implementation and the performance evaluation for the model based on Globus Toolkit 4 are further presented.关键词：cryptology;resource allocation;task dividing;computational grid2|907|0更新时间：2025-07-16
- 摘要：This paper proposes COPP,i.e.chirp of packet pairs,a novel active method to yield available bandwidth along network paths.The probes in COPP are composed of several chirps of packet pairs,e.g.several trains of packet pairs where the interval between the first and the second packet within packet pair is gradually decreased.For each chirp of packet pairs traversed the measured path,we find out all turning points in the chirp,and then give them distinct weight in the final available bandwidth calculation according to the degree of experienced distortion.The turning point is such a packet pair that is disturbed more obviously by cross traffic in contrast to its neighbor pairs.Two rules are developed to determine whether a packet pair is a turning point or not.Additionally,COPP can determine its estimate bound dynamically by exploiting the bandwidth requirements of concrete applications if known.We also inspect the selection of the probe packet size in COPP through simulations.Finally,comparisons between COPP and other measurement tools such as Pathload and Spruce show that COPP is an agile and stable technique and can provide relatively higher accurate results with fewer overheads.关键词：active probing;available bandwidth;packet pair2|643|2更新时间：2025-07-16
- 摘要：Linear Cryptanalysis is one of the most important attacks on block ciphers.In this paper,the linear provable security for a class of unbalanced Feistel networks is investigated deeply.Using the structure of linear deviation,we prove that the upper bound of r-round(r≥m) linear hull probabilities are bounded by LP×LP and r-round(r≥2m) linear hull probabilities are bounded by 2(LP× LP×LP×LP) when the maximal linear hull probabilities of round function is LP and rounds keys are independent and uniformly random.关键词：unbalanced Feistel networks;the linear provable security;linear hull probabilities;upper bounds2|695|3更新时间：2025-07-16
- 摘要：Least privilege mechanism can provide a reasonable degree of security assurance for secure operating systems.This paper described a framework for implementing dynamically modified least privilege security policy,which combined role’s duty separation property and domain’s function separation property.Under the control of its new capability mechanism based on a process’s executable image,current role and current domain,it restricted the process to the minimum amount of privileges within these contexts.This paper illustrated its implementation in ANSHENG OS v4.0,a copyrighted secure operating system satisfying all the specified requirements of Criteria class 4,"Structured-Protection",in GB17859-1999 (equally,the B2 level in TCSEC) in China.Thus it demonstrates that this framework can help enforcing dynamically least privilege control on a secure operating system,while still providing a flexible efficient system.关键词：secure operating system;security policy;least privilege;capability;role;domain2|1053|1更新时间：2025-07-16
- 摘要：More and more intruders exploit the vulnerabilities of system and applications to intrude the system.This paper introduced an anomaly intrusion detection model analyzing processes' behaviors.It introduces the similarity calculation method based on Vector-space.And it introduces an argument to value the capabilities of system calls to differentiate the process behaviors.Thinking of the characters of the abnormalities caused by intrusions,the detection algorithm adopts the method of locally analyzing.关键词：intrusion detection;anomaly detection;nonhierarchical clustering2|2024|9更新时间：2025-07-16
- 摘要：The most important tool to protect data integrity is Message Authentication Code(MAC),which is widely used in many kinds of secure systems.With the development of the theory of provable security,the MACs,which have security proof,are the first choice of many people.Based on the constructions of XOR MAC and PMAC,we define a deterministic fully parallelizable block-cipher mode of operation for message authentication-DXOR MAC(Deterministic XOR MAC).We prove its security,quantifying an adversary's forgery probability in terms of the quality of the block cipher as a pseudo-random permutation.关键词：message authentication code;pseudo-random permutation;provable security;game-playing2|704|2更新时间：2025-07-16
- 摘要：Considering both of Spread spectrum and quantization can complement,a hybrid-watermarking model is constructed by integrating spread spectrum with quantization technique.Furthermore,a novel hybrid-watermarking scheme is proposed based on spread spectrum and quantization in multiwavelet domain.The performance analysis is used to describe the interrelations among length of sequence,channel capability,detection error rate and so on.Moreover,the experimental results demonstrate that the proposed algorithm provides the capacity maximization under the precondition of robustness.关键词：digital watermarking;dirty paper model;spread spectrum;scalar Costa scheme;multiwavelet transform2|1166|2更新时间：2025-07-16
- 摘要：In this paper,a novel data partitioning method is presented,aiming at reducing error propagation for video streaming.The proposed method modifies the approach defined in H.264,differentiating the importance level of every encoded macroblock by using the degree of the error propagation caused by the loss of the macroblock and then forming separate sub-bitstreams.Given the network bandwidth and packet loss rate,a bit rate allocation algorithm based on rate-distortion optimization is presented to protect individual sub-bitstreams at different levels,which enhances the possibility of correctly receiving the macroblocks of high level and improves the reconstructed quality of video streaming.The proposed method is easy to implement.Most important,the method effectively reduces the error propagation as packet loss happens.The simulations show that the proposed method gains 0.3-0.6dB than H.264 under the same channel conditions.关键词：video streaming delivery;data partitioning;video error resilience;error propagation;UEP2|929|0更新时间：2025-07-16
- 摘要：Region Of Interest(ROI) coding is an important technology presented by JPEG2000.However,JPEG2000 can not support arbitrary-shape ROI and any scaling value at the same time.A 3D volumetric image compression algorithm based on the arbitrary-shape ROI and 3D lifting wavelet zeroblock coding is proposed.New scheme supports lossy to lossless compression between inside and outside ROI.A simple"bit lifting"method for the generation of the lossless ROI mask for arbitrary-shape ROI is proposed.Considering the feature of 3D subband,we employ 3D zeroblock algorithm which is a modified 3DSPECK algorithm to encode transformed coefficients.Some coding techniques that can realize arbitrary-shape ROI coding are evaluated.Experimental results show the proposed algorithm exhibits much better performance.关键词：3D image coding;embedded coding;3D wavelet transform;3DSPIHT;3DSPECK2|662|1更新时间：2025-07-16
- 摘要：Linear constrained constant modulus algorithm (LC-CMA) is an effective solution to the problem of interference capture in constant modulus algorithm (CMA).But its performance is known to degrade substantially in the presence of even slight mismatches between the actual and presumed signal steering vectors.In this paper,we propose a novel approach to robust adaptive beamforming and analyze its performance.Our robust constrained constant modulus algorithm offers faster convergence rate,provides excellent robustness against the signal steering vector mismatches and improves array output SINR consistently.Computer simulations show better performance of our proposed robust adaptive beamforming algorithm than that of linear constrained constant modulus algorithm.关键词：constant modulus algorithm (CMA);linear constraints;robust adaptive beamforming algorithm;signal-to-interference-plus-noise ratio (SINR)2|788|3更新时间：2025-07-16
- 摘要：Aim at the problems that the inputs and outputs of some practical nonlinear systems are Continuous time signals,we brought forward a Continuous process neuron and process neural networks model.The input and output of the defined process neuron are Continuous time functions,and the space-time aggregation operation can reflect the space aggregation of the input signals and the time cumulative effect in the process of input at the same time,and can also realize the nonlinear real-time mapping between the input and output.A Continuous feedforward process neural networks model is given in this paper,and the corresponding property theorems are also proved,including continuity,function approximation ability and computational capacity.关键词：system with time-varied input and output;continuous process neural networks;function approximation ability;computational capacity;continuity2|648|27更新时间：2025-07-16
- 摘要：Short time Fourier Transform (STFT) of Doppler spectrum analysis has provide a effective lossless detecting means for blood velocity measurement and diagnosis of artery strait disease in the past.There must be analysis error using the transform for long interval unsteady blood fluid signals.Due to variable flexible spatio-temporal windows,wavelet has much more predominance when analyzing Doppler blood signals.An innovative auto-wavelet correlation analysis (AWCA) method is put forward here,which can be used in analysis of Doppler blood signals.It is given the simulative experimental signals and the analysis results,compared AWCA with STFT at last.The results indicate that AWCA method not only adapts to analyze unsteady Doppler blood signals,it can also provide better resolution properties of position and frequency.关键词：ultrasonic doppler signals;blood velocity;short time fourier transform;auto-wavelet correlation analysis2|1414|3更新时间：2025-07-16
- 摘要：For the multi-variable nonlinear coupled system with strong disturbance such as the gas pressure of collectors of coke ovens,this paper proposes an intelligent multi-level coordinated control strategy based on multi-agent system.It adopts the multi-level coordination architecture with agent agency and the organization and evolution mechanism based on task decomposition.The system can be switched to different modes using the state change of agents in order to operate in rapidly time-varying environments.The reinforcement learning method is used in Agent learning,the TS type recurrent fuzzy neural network(TSRFNN) is employed to realize the actor-critic elements.The agents in system are optimized coordinately by using the distributed learning algorithm.The real-world application shows that the proposed control strategy has successfully solved the process coordination control problem of the gas pressure of collectors of coke ovens with the strong disturbance produced by high pressure ammonia.关键词：gas collectors of coke ovens;cascade coordination;multi-Agent system;reinforcement learning;TS recurrent fuzzy neural network2|1505|3更新时间：2025-07-16
- 摘要：To evaluate the quality of gold plating on coaxial connectors,the wear resistance of gold plating must be tested because the base materials of connectors would be exposed and corroded during applications if the gold plating were worn out,which would lead to contact failure.The surface hardness of contacts on connectors and the thickness change of gold plating before and after mating can be taken as the references for wear resistance ability of gold plating.Single gas (sulfur dioxide) accelerated corrosion joint with the optical microscope and the scanning electronic microscope can disclose the characteristic points where the gold plating are worn out.This is a good method to evaluate wear resistance ability of gold plating on coaxial connectors.关键词：gold plating;wear;accelerated corrosion;coaxial connectors2|634|1更新时间：2025-07-16
- 摘要：One of factors that influences brain computer interface (BCI’s) with high information transfer rates is selection of appropriate signal processing methods to extract the user's messages and commands from electroencephalograph (EEG).EEG is highly colored and non-gauss signal,the frequency of EEG is irregular and was the same as the event-related potential(ERP).According to the theory that decay of wavelet local modulus maxima of signal and white noise is different,we develop a new method based on Autoregressive Model and wavelet multiresolution analysis.Results from a series of actual experiments show that,this method can extract ERP components from single trial exactly.关键词：brain computer interface(BCI);wavelet transform;imitating natural reading event-related potential(ERP);autoregressive model;single trial ERP extraction2|812|2更新时间：2025-07-16
- 摘要：In OFDM systems,clipping is often used to control the high peak-to-average power ratio (PAPR) of signal.Clipping will introduce additional clipping noise on both data and pilot symbols,so as to degrade the system performance.A new technique is proposed to cancel the clipping noise on pilot symbols for clipped OFDM systems.The new technique is based on directly filtering the clipping noise on the positions of pilot symbols before they are inserted into the data.Based on the new technique,an iterative method is proposed to further improve the performance of channel estimation.The simulation results are also given.It is shown that the new technique and the iterative method can effectively improve the performance of channel estimation,so as to improve the system performance.关键词：clipping;OFDM;pilot symbol;channel estimation2|643|1更新时间：2025-07-16
- 摘要：A new service differentiation scheme based on packet arrival rate diversity is proposed for IEEE 802.11 WLAN.An analytical model is developed for performance evaluation.It’s shown that the new scheme can achieve effective service differentiation and statistical throughput guarantee by controlling the total offered load.The scheme requires no modifications at 802.11 MAC layer.Simulation results validate the analytical model.关键词：IEEE 802.11;service differentiation;packet arrival rate;markov chain model2|610|0更新时间：2025-07-16
- 摘要：This paper dealt with the capacity behavior of a new transmission technique for the multi-antenna system,which was proposed based on the fact that multiple independent channels as well as the points in modulation constellation can be mapped by the input of information data.An analytic expression of the channel capacity for the new transmission technique was derived and the numerical results proved that compared to the traditional random transmit-antenna selection technique with the same antenna structure,the new transmission technique can achieve more channel capacity gain.关键词：capacity;ergodic capacity;multiple antenna system;transmit-antenna selection2|875|0更新时间：2025-07-16
- 摘要：Based on the concept of contention reservation for polling transmission and collision prevention strategy for collision resolution,a fair on-demand access (FODA) protocol for mobile ad hoc networks (MANET) is proposed.In the protocol,a clustering network architecture acquired by clustering algorithm and reserving channel resources by fair collision prevention (FCP) algorithm to obtain polling service are adopted,so that the hidden terminals (HT) and exposed terminals (ET) problems existed in traffic transmission due to carrier sensing,multihop architecture and wireless transmission method can be completely eliminated.In addition,the FCP algorithm can also completely resolve unfair phenomena and access collisions in the present of contention access of newly active nodes.Finally,performance comparison of the FODA protocol with carrier sense multiple access with collision avoidance (CSMA/CA) and polling protocols are presented and simulation results show that the proposed protocol can achieve higher throughput,lower average message dropping rate and delay.关键词：mobile ad hoc network;multiple access protocol;on-demand;polling;fair access;collision prevention2|991|0更新时间：2025-07-16
- 摘要：It is essential to design QoS supported MAC mechanism for supporting QoS in wireless LAN.We have proposed a new backoff algorithm,names RWBO+BEB,to dramatically decrease the packet collision probability.In this paper,we explore how to make RWBO+BEB support service differentiation.A Markov model is proposed to analyze how to choose the minimum contention windows according to the bandwidth ratios of stations.Based on the analysis,a novel service differentiated backoff algorithm for IEEE 802.11 DCF,named DS-RWBO,is proposed.The simulation results indicate that DS-RWBO can allocate the wireless bandwidth according to the bandwidth ratio of each station.关键词：IEEE802.11;wireless LAN;service differentiation;service differentiated RWBO2|675|5更新时间：2025-07-16
- 摘要：In this paper,we propose a new adaptive dual mode semi-blind channel estimator based on iterative soft information processing.A new reliability measure function is constructed to calculate the reliability factor of the reconstructed signal from the decoder and soft mapping.An option is made adaptively between the decision directed mode and blind estimation mode by comparing the reliability factor with a specified threshold.The estimated channel frequency response can improve the performance of the iterative receiver.Simulation results show that the proposed algorithm combines the two algorithms’ advantages and limits the conventional DD mode’s error propagation.It can track the time-varying channel efficiently without scattered pilots and achieve good system performance.关键词：DD(decision directed);BCJR algorithm;EM algorithm;least square algorithm2|781|1更新时间：2025-07-16
- 摘要：A Pre-processing Least Squares Constant Modulus blind multiuser detection Algorithm based on Decision-Feedback (PDF-LSCMA) in antenna array system is proposed in this paper.It pre-processes the received signals from the antenna array and utilizes the least squares constant modulus algorithm based on decision feedback to detect the DS-CDMA signals.This algorithm can ensure the convergence to the expected signal and enhance the performance of the system.The robustness of PDF-LSCMA to the DOA estimation error and the maximum value of DOA estimation error are also analyzed in this paper.Simulation validates the algorithm and theoretical analysis.关键词：antenna array;blind multiuser detection;direction of arrival;robustness2|504|0更新时间：2025-07-16
- 摘要：Based on the principle of high frequency(HF)DFH,this paper preliminarily proposed the classification of parameters for the first time,which DFH network make-up needed,studied its network make-up method,extended implication of synchronous frequency hopping network make-up,and paid emphases on the derivation of the theoretical characteristics of the network making-up asynchronously by taking the method of statistics,discussed the relationships between the multiple-access interfere probability and the numbers in a asynchronous DFH network,as well as with the corresponding relationships between the efficiency and the multiple-access interfere probability,then obtained some good conclusions finally.关键词：high frequency(HF)radio;differential frequency hopping(DHF);frequency hopping network make-up2|1037|2更新时间：2025-07-16
- 摘要：This paper presents the REESSE1 public key cryptosystem including three algorithms for keys,encryption and decryption,discusses the continued fraction attack by presuming that the lever function (.) in the key transform is one constant or does not exists,and proves that (.) is necessary to the private key security of REESSE1 from the contrapositive assertion.The authors argue that the private key security is equivalent to the multivariate arrangement hardness,and the plaintext security is greater than the discrete logarithm hardness when (.) exists in the transform by expounding the indeterminate reasoning,giving counterexamples and reducing parameters,and so show that (.) is sufficient for the private key and the plaintext securities.At last,point out that the complexity of REESSE1 whose private key contains three independent parameters is far higher than those of MH,RSA and ElGamal whose private keys contain only one or two parameters respectively.关键词：public key cryptosystem;security;lever function;continued fraction;encryption2|989|1更新时间：2025-07-16
- 摘要：Automatic extraction and matching of a set of significant feature points on different image views on the face is a very hard machine task.In this paper,in order to bypass this problem,our method recovers both the pose and the 3-D face coordinates using shape match morphing model and iterative minimization of a metric based on the structure match.A radial basis function (RBF) in 3D is used to morph a generic face into the specific face structure and shape context (SC) is used to descript point shape.Based on RBF and SC,shape distance is used to metric the similarity of two shapes.Experiment results are shown for images of real faces and promising result are obtained.关键词：3D reconstruction;shape context;shape distance;radial basis function;3-D morphing2|784|3更新时间：2025-07-16
- 摘要：In the robust principal component analysis(RPCA)model,the statistical properties of every variable are neglected when scale parameters are chosen for them.In order to overcome this drawback,a generalized robust principal component analysis(GRPCA)model was proposed in this paper,a M-estimator was adopted to estimate robust scale parameters for every variable according to their statistical properties.Then,a new independent component analysis algorithm for face recognition based on wavelet decomposition and robust estimation (WR-ICA) was proposed.WR-ICA is robust to many types of outliers (incomplete face image,making up,occlusion,etc).The validity of WR-ICA is confirmed by theory analysis and experimental data,with Cos distance as similarity measurement,the average recognition rate of WR-ICA is 99.44%.关键词：face recognition;principal component analysis;independent component analysis;wavelet decomposition;robust estimation2|1271|2更新时间：2025-07-16
- 摘要：Role authorization is very important in RBAC models.Existing formalized methods focus on explicit description.Based on current RBAC models and associated with information hiding technique of watermarking relational databases,a digital watermark based database model using RBAC (WRBAC) and its framework are provided.Then,digital watermark algorithms about role authorization are emphasized.Finally,implementation of WRBAC model in our intrusion tolerance database environment is provided.关键词：Role-based Access Control (RBAC);digital watermark;security database model;intrusion tolerance2|1272|3更新时间：2025-07-16
- 摘要：In order to solve the conflicts between searching precision and searching speed of motion vectors in video coding,a fast MMS (Multi-Mode Search) algorithm based on GA (Genetic Algorithm) and DS (Diamond Search) is proposed in this paper.Its searching modes can be switched adaptively by the criterion of drastic level of the predictive motion vectors derived from the spatio-temporal coherence of the video sequences.In the mild motion mode,DS method is used directly;In the drastic motion mode,a combined GA/DS searching method is adopted.Comparing with nowadays fast sub-optimal searching methods,MMS can solve the performance falling problem in case of large motion vectors,which enhance the capability of video encoders thoroughly.Its performance is near to the results of ideal FS (Full Search) algorithm.Comparing with other searching methods using GA directly for obtaining global optimum,MMS combines DS with GA to achieve rapid convergence speed.Furthermore,by introducing multi-mode processing conception,the efficiency of sub-optimal searching methods is fully carried out.Its searching speed is nearly as fast as DS.And its searching precision is guaranteed simultaneously.This algorithm provides a new framework for solving the conflicts in motion estimation problems in video coding.The experimental results have rectified its effectiveness.关键词：video coding;motion estimation;genetic algorithm (GA);diamond search(DS);multi-mode search(MMS);adaptive;spatio-temporal coherence2|1248|5更新时间：2025-07-16
- 摘要：Phonemes are often used in speech recognitions.The amount of phonemes makes the RNN's training complicated.Moreover,different modules need to be built up for different languages in multi-language speech recognition.Government Phonology (GP) provides new primes,which can be used to describe the speech features of different languages.According to the similarity of the pronunciation of English and Mandarin,we introduced GP expressions of Mandarin phonemes and used RNN to extract mandarin GP features.As the experiment results show,GP primes can also be used in describing Mandarin speech features.关键词：GP features;feature extraction;mandarin;multi-speech recognition2|1005|0更新时间：2025-07-16
- 摘要：A Genetic Algorithm (GA) based Global Motion Estimation (GME) method is proposed for compressed videos.Using motion vectors in compressed videos directly for GME,this approach utilizes GA to optimize the fitting errors between the input motion vectors and the ones generated from the estimated global motion parameters.Experimental results on different type of global motions show that the proposed genetic algorithm based global motion estimation method is satisfying.Moreover,a text-occluded region recovery approach is presented using the estimated global motion parameters,based on the Global/Local Motion(GM/LM) information for text occluded region in the video sequences.Experimental results on different videos show that this method achieves better visual results.关键词：global motion estimation;video text;motion vector;genetic algorithm;text occluded region recovery2|869|0更新时间：2025-07-16
- 摘要：To reduce the halving and the doubling errors in pitch tracking,an algorithm based on a combined magnitude difference function is proposed in this paper.By analyzing the error distributions in different algorithms based on magnitude difference functions and autocorrelation functions,a combined magnitude difference function (CMDF) is defined,which has the best performance compared with the others.Moreover,a post processing method is proposed which uses the history information to adjust the raw pitch estimated using the CMDF.The post processing method uses only the history information,thus the pitch tracking algorithm has low latency,which reduces the pitch estimation errors that often occur in traditional methods.Experiments show that the pitch tracking algorithm proposed in this paper can achieve a pitch error rate reduction of 13.8% compared with the baseline traditional algorithm.关键词：speech processing;pitch tracking;combined magnitude difference function2|1245|5更新时间：2025-07-16
- 摘要：A new approach for modeling non-stationary time series was introduced in this paper.Combine the fuzzy segmentation which was proposed by Janos Abonyi with Support Vector Machines(SVMs).Firstly,a modified Support Vector Regression(SVR) was proposed;Secondly,fuzzy segment information was combined with SVR by heuristic weighting method;Thirdly,we discussed a model based on multi-SVR.Experimental results show that the method proposed in this paper has great practical values for non-stationary time series modeling.关键词：non-stationary time series;fuzzy segmentation;heuristic weighting method;multi support vector regression2|881|1更新时间：2025-07-16
- 摘要：An analytical model to calculate the electroluminescence (EL) profiles in single layer structure was presented,taking into account the charge injection process at each electrode,hopping transport in disordered system,disassociation and recombination of polaron-excitons.By simulation,the influence of disassociated distance on recombination efficiency and the influence of injection and recombination on EL efficiencies are thoroughly studied.When using both ohmic contacts or an ohmic contact and a contact limited contact,the EL efficiency is determined by injection at lower voltages and recombination at higher voltages.When using both contact limited contacts,the EL efficiency is determined by the injection process.By comparison of the theoretical results with the experimental data reported in the literature,we found this model can reasonably elucidates the influence of some factors on injection and recombination.关键词：OLEDs;electroluminescent efficiency;injection efficiency;recombination efficiency2|655|0更新时间：2025-07-16
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