最新刊期
卷 41 ， 期 7 ， 2013
- 摘要：The current Internet has three types of bindings,namely the binding between resource and locators,the binding between control and data,and the binding between identity and locator.The resulting network architecture makes the network being relatively static and rigid.This makes it difficult for the Internet to satisfy the current demands including high-speed,high efficiency,high throughput,and pervasiveness.In addition,this also makes it hard for the network to be scalable and secure,support efficient host mobility,being efficient resource utilization and energy saving.In order to address these issues once and for all,we propose a novel network architecture called smart and cooperative network architecture.The network architecture has three layers,called the smart service layer,the resource adaption layer,and the network component layer.It also has two realms,called the entity realm and the behavior realm.Based on this architecture,we outlined the basic theories of the three layers,respectively,in order to make a future Internet being able to support efficient host mobility,be scalable and secure,being efficient resource utilization and energy saving,and to offer improved user experience.关键词：future internet architecture;smart and cooperation;adaptive resource allocation2|3443|22更新时间：2025-07-16
- 摘要：The current Internet has serious shortcomings in service supporting,such as complicated in service naming,rigid in service allocation,etc,so it can't adapt well to increasing multi-demands of future Internet,and it's necessary to study new Service Mechanisms.Based on the new architecture of smart and cooperative networks,we propose a new model of smart service.First we give the method of service naming and description for service behavior.Second we propose the mechanism of service registering and searching.Third we bring forward the method for service storing and apperceiving.In the end,we give the mapping mechanism between service ID and Family ID.Our new architecture of smart service overcomes the shortcomings of current Internet,and improves user experience.关键词：smart service;service identifier;description of service behaviour;dynamic allocation2|2348|11更新时间：2025-07-16
- 摘要：The current Internet architecture and mechanisms are relatively static and rigid,which makes it difficult for the Internet to support smart communication.To overcome the serious shortcomings of the Internet,it is necessary to establish new network architecture and its related theories and mechanisms.Based on long term fundamental research on information networks and our previous 973 project,in this paper,we propose a novel cooperation architecture and model for smart network components under the smart and cooperative network architecture with three layers and two realms.Based on this architecture,we present smart network component model,family aggregation mechanisms and gaming decision mechanisms for complex network behaviors.In addition,related cooperation mechanisms of smart network components are designed to support smart network communication,which effectively address the issues of resource utilization and energy saving in current Internet.关键词：network component;family aggregation;gaming decision;smart cooperation2|2365|13更新时间：2025-07-16
- 摘要：Building virtualized network experiment platform is considered to be an effective method for network architecture innovation and validation.The structure and performance of the virtual router determines the capacity and flexibility of network experiment platform.In this article,the virtual router's data-plane architecture with parallel pipelines is presented.Combined with parallel packet classification and asynchronous pointer polling scheduling mechanisms,we implement isolated heterogeneous router instances on the same physical underlying.Prototype system is deployed on programmable hardware which is tested with software routers in real network environment.Experimental results show that compared with traditional single-pipeline architecture,our design get greater flexibility and parallelism and supports heterogeneous router instances operating independently;logic resources overhead and delay characteristics are not significantly increased while each router instance achieves wire-speed forwarding which is comparable with that hardware.关键词：virtualization;data plane;parallel pipeline;programmable hardware3|1492|3更新时间：2025-07-16
- 摘要：Two-scale similarity transform(TST)presented by V.Strela is an important role in studying the multi-wavelet.The concept of general conjugate two-scale similarity transform(GCTST)is introduced in this paper.GCTST is the most universal generalization of TST.We discuss how the GCTST change the eigenvalue of the matrix by using the general inverse matrix theory,which the former authors hardly use.Then we show that GCTST can keep the approximation order of the multi-scaling function,balance the unbalanced multi-scaling function and keep the symmetry of the multi-scaling function.By the two examples,we conclude that the GCTST transform is feasible and efficient.GCTST also change the multiplicity of the multi-scaling function.关键词：general conjugate two-scale similarity transform(GCTST);the multi-scaling function;general inverse matrix;wavelet2|1104|0更新时间：2025-07-16
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An Efficient DOA Estimation Method for Wideband Coherent Signals in the Presence of Correlated Noise
摘要：In this paper,we propose an efficient direction of arrival estimation method for wideband coherent signals in the presence of correlated noise with uniform linear array.Firstly,the component of correlated noise is eliminated by using the spatial differencing technique and then a new matrix is constructed by performing the squaring operation at each frequency bin.Afterwards,a universal covariance matrix is obtained by performing a focusing operation.Finally,the coherent signals are resolved by applying the propagator method.The signal number in a coherent group resolved by the proposed method can be even or odd.Simulation results demonstrate the effectiveness and performance of the proposed method.关键词：wideband coherent signal;direction-of-arrival estimation;uniform linear array;spatially correlated noise;propagator method2|1362|6更新时间：2025-07-16 - 摘要：For nonconstant modulus signals,the steady-state mean square error(MSE)of constant modulus algorithm(CMA)for blind equalization can not converge to zero and CMA can not achieve modulation classification.According to the construction method for CMA's cost function,a cosine cost function is defined and a new blind equalization algorithm based on it is proposed.Such cost function can take all the constellation points of BPSK,M-PAM and M-QAM signals mapped to the origin of constellation diagram,so the steady-state MSE of the proposed algorithm can converge to zero for both of constant modulus and nonconstant modulus signals.Furthermore,for above signals the proposed algorithm has the modulation classification ability under the condition of multipath propagation.Theoretic analysis and computer simulation results demonstrate that the proposed algorithm offers high performance.关键词：blind equalization;multipath propagation;modulation classification;constant modulus algorithm;cosine cost function2|1699|4更新时间：2025-07-16
- 摘要：In this paper,we propose a path selection scheme based on the idea of autonomous learning for concurrent multipath transfer (CMT) in path selection.Firstly,this autonomous learning scheme integrates the requirements of a specific service,such as throughput,delay and loss rate,to define the optimization object function.Secondly,this scheme sets several parameters of path selection as the learning parameters.During the transmission,through analyzing the relationship between different values of learning parameters and the actual measured values of object function,the system performs its autonomous learning,and gradually gets the best value combination of learning parameters.Experimentations show the feasibility,convergence and stability of the scheme,and also demonstrate the scheme could adjust the learning parameters by itself to adapt the changing network condition and gain the best value of object function.关键词：autonomous learning;concurrent multipath transfer (CMT);optimization;path selection2|1403|0更新时间：2025-07-16
- 摘要：In this paper,a new method which combines with covariation,cyclostationarity and FLOM for calculating low order spectrum based on FAM(FFT Accumulation Method) was proposed and the simulations were made for modulated signals(AM,QPSK),and finally the cycle leakage and complexity of this method were analyzed.The result under α stable distribution shows that the spectrum instruction of two order cyclostationary signals is the same as under Gauss model.However,the methods constructed under stable distribution have better performance of anti-noise than under Gauss model.The low order cycle characteristic parameters are constructed in the field of cycle spectrum and a new method is given for modulation recognition and blind separation in complex environment.关键词：αstable distribution;FLOM;FAM;Gauss model2|2117|4更新时间：2025-07-16
- 摘要：A multiuser Amplify-and-Forward (AF) relay system is considered in which the source is equipped with multiple antennas,while the relay and each of multiple destinations have a single antenna.Orthogonal Space-Time Block Coding (OSTBC) is employed to achieve spatial diversity and opportunistic scheduling is used to obtain multiuser diversity.Closed-form expressions for outage probability and average Symbol Error Rate (SER) in independent but not identically distributed (i.n.i.d.) Rayleigh fading multiuser environments are derived for adaptive-gain and fixed-gain relaying methods.Asymptotic expressions for outage probability and average SER at high SNR are presented and used to determine the diversity order of the two relaying systems.The combined effect of spatial and multiuser diversity is quantified for the proposed system.Monte Carlo simulations demonstrate the accuracy of the analyses presented.Comparisons among the relaying methods and multiuser point-to-point systems are provided along with insights.关键词：multiple-antenna systems;wireless relaying systems;Orthogonal Space-Time Block Code (OSTBC);multiuser diversity2|1286|3更新时间：2025-07-16
- 摘要：The concept of bidimensional signal detachable degree is explained and analyzed.Based on the Bidimensional Empirical Mode Decomposition(BEMD)theory and the bidimensional signal analytic phase theory,this paper brought out add and product detachable degree calculation formulas for bidimensional empirical mode signal.To verify these two formulas'actual effects,we performed experiments with complete add detachable signal and complete product detachable signal.The application of bidimensional empirical mode detachable degree shows that it can identify the BEMD algorithm's quality and has capability to determine the objective BEMD stopping criterion.It also provides an effective basis for the choice of preprocessing methods when extracting single orientation features.关键词：bidimensional signal detachable degree;bidimensional empirical mode decomposition;analytic phase;add detachable degree;product detachable degree2|1634|3更新时间：2025-07-16
- 摘要：The current methods of motion artifact suppression in magnetic resonance imaging(MRI) are generally based on the K-space data.In this paper,an image post-processing method is proposed,which can directly apply to the MR images and correct the motion artifact.We designed a model based on non-local means total variational (TV) method,which consists of the non-local regularization term and patch similarity fidelity term.The regularization term can keep the image structure while correcting the motion artifact.Introduce the anisotropic diffusion structure tensor to the patch similarity fidelity term as its weight function,which can implement different diffusions process in different regions and can remain the details of the image while removing the motion artifact.The numerical scheme uses the split Bregman method.Experiments showed that the motion artifact was effectively reduced and the valuable details of images were remained and the arithmetic speed was improved.关键词：motion artifact;MRI (magnetic resonance imaging);structure remain;non-local means2|1813|3更新时间：2025-07-16
- 摘要：Through the research on the structure tensor and the analysis of the texture image,a scalar texture feature descriptor based on eigenvalues of structure tensor is designed.Embedding the descriptor and the original image into the two-phase fuzzy region competition model and the CV model respectively,an unsupervised texture image segmentation model which combines texture with intensity information is given.The Chambolle dual method is adopted in order to minimize the optimum global solution of the new model.According to the related experiments for natural and synthetic images,the new method has some advantages including faster convergence speed due to less feature channels and more precise segmentation results.关键词：structure tensor;texture image segmentation;dual method;fuzzy region competition2|1598|8更新时间：2025-07-16
- 摘要：Based on sparse regularization to the membership functions,this paper proposes a novel multiphase variational model and corresponding algorithm for image segmentation.The proposed model and algorithm has three main advantages.Firstly,the sparse regularizer performs better than total variation regularizer.It protects edges from oversmoothing which is a common drawback of the total variation regularizer.Secondly,the multi-scale geometric analysis tool well preserves geometric shape of the segmentation regions.Finally,the proposed algorithm is simple and has rapid running speed.A series of experimental results demonstrate the feasibility and effectiveness of the proposed method.关键词：image segmentation;sparse representation;wavelet;curvelet;splitting algorithm;variational model2|1464|3更新时间：2025-07-16
- 摘要：Solving the data sparseness problem is an important problem about head-driven parsing,cluster-based statistic language model is an important method to solve the problem of sparse data.Based on the analysis of the classical smoothing technology,this paper proposes a word clustering algorithm by utilizing mutual information and semantic dependency,and an absolute weighted difference method was presented and was used to construct vari-gram language model which has good predictable ability,then proposes an improved head-driven parsing model based on word cluster and vari-gram model.Experiments are conducted for the refined statistical parser,it achieves 84.53% precision and 82.41% recall,F measure is improved 2.02% comparing with the head-driven parsing model introduced by Collins.关键词：parsing model;smoothing algorithm;head-driven parsing;clustering algorithm2|1371|2更新时间：2025-07-16
- 摘要：The same challengs facing model checkings in probabilistic real-time temporal logic of knowledge PTACTLK is the same as traditional model one.That is the state space explosion problem.Abstraction is one of the most effective methods to alleviate the state space explosion problem.In order to alleviate the problem of the state space explosion in model checking probabilistic real-time temporal logic of knowledge,an abstraction technique is presented.For the real time part of PTACTLK,that is PTACTL,we adopt the abstract discrete clock valuations,and the infinite state space of a probabilistic real time was interpreted into a finite form.For the epistemic operator K in PTACTLK,the definition of epistemic equivalent to an agent between abstract states is given.We define the abstract model of the interpreted system in a probabilistic real time and present the semantics of PTACTLK on the abstract model.We prove that the abstract model obtained by using the abstraction techniques is the upper approximation of the original model.At last,a simple communication protocol is adopted to illustrate the effectiveness of our abstraction techniques.关键词：model checking;probabilistic real-time temporal logic of knowledge;PTACTLK;state space explosion;abstraction2|1279|2更新时间：2025-07-16
- 摘要：Ternary reversible logic synthesis is the extension and expansion of reversible logic synthesis.In order to simplify the reversible network and improve the generality of ternary reversible logic gate,the effective value of controlling bits of the existing ternary reversible controlled gates can be extended to any of 0,1 and 2.And on the basis of that,a ternary reversible logic synthesis algorithm with minimum chaos degree is proposed.The algorithm is used to compute the relative chaos degree and absolute chaos degree of each variable in truth table under ternary logic system,according to the reversible function.As one reversible logic gate is selected,the principle of minimal chaos degree in ternary reversible logic synthesis should be followed until the relative chaos degree and absolute chaos degree of each variable in truth table decrease to 0,which means the synthesis has been finished,and the reversible network can be derived.The time complexity for the algorithm is O(n2×3n),and its space complexity is O(n×3n).The experimental results show that the average number of gates is less than the existing algorithms as known.关键词：ternary reversible logic gate;ternary reversible logic synthesis;chaos degree2|1347|0更新时间：2025-07-16
- 摘要：IP cores without I/O multiplexing are typically unavoidable to be embedded into SoC due to the necessary considerations such as pin constraint and performance optimization during the design stage.Hence,one of the serious challenges for SoC testing is how to effectively test IP cores without I/O multiplexing because the ports of IP cores without I/O multiplexing cannot be directly connected to the ATE channels.In this paper,we propose test methods for ADC and DAC IP cores without I/O multiplexing using V93000 ATE respectively.In order to test the ADC and DAC IP cores without I/O multiplexing,test programs are firstly developed and loaded into V93000 to configure the two cores via EMIF bus.Then the digital codes and the analog voltage values respectively converted by ADC and DAC IP cores of SoC are captured by V93000 for performance parameter calculation.Experimental results show that the proposed methods are effective.关键词：System-on-a-Chip;ADC;DAC;V93000 ATE;performance parameter2|1879|4更新时间：2025-07-16
- 摘要：BPEL achieves reusability and value-adding of Web service through composing individual services.Meanwhile,it brings some challenges because of its complexity.For example,guaranteeing the data flow correct is very important for the correctness of BPEL process.However,few literatures focus on the data flow related analysis and verification.In this paper,we proposed an XCFG based technique,which models BPEL with XCFG and designs corresponding algorithms to analyze and verify the typical data flow property of BPEL,such as the consistency of define-use,deadlock-free and reachability.Both theoretical and experimental study validates the effectiveness of the XCFG based technique.关键词：Web service composition;extended control flow graph(XCFG);data flow property;verification2|2032|1更新时间：2025-07-16
- 摘要：Existing built-in self-repair (BISR) methods are either inefficient using traversal address compare or high power consumption using parallel address compare.Neither is suitable for memories with large fault quantity.In order to solve this issue,an efficient memory BISR method based on hash table is proposed.In the proposed method cell fault addresses which contribute the main part of memory faults were stored in the form of a hash table.With quick search feature of hash table the proposed method improves address compare efficiency radically.Under work mode address compare process can be finished within 1 clock cycle,and this will ensure repaired memory against additional performance penalty.The proposed method achieves the same address compare efficiency to CAM based method with much lower power consumption.Experimental results show that for 512?512?8 bits memory the proposed method achieves 32.25% repair rate increment on average to ESP method with the same redundancy overhead.关键词：built-in self-repair;Hash table;built-in redundancy analysis;built-in self-test2|1821|0更新时间：2025-07-16
- 摘要：To find a new light source,especially short-wave coherent light source has been to strive goal of the people.A combination between crystalline Undulator field with the klystron technology is expected to be short-wave coherent light source,in particular the coherent γ-light source.In the paper discussed the possibility of a periodic bent crystal as γ-klystron by Lasing effect of the periodic bent crystal.In the framework of classical mechanics and the small gain approximation,the longitudinal motion equation of the particles in the crystalline Undulator is reduced into classical pendulum equation,and derived the energy gain of the system by perturbated method.The results show that when the bent crystal worked in the amplifier mode,the required beam intensity is more high.If the bent crystal worked in the cascading klystron mode,the requirements of beam intensity can be reduced by 3-4 orders of magnitude,entirely lie within the capabilities of today's accelerator technology.关键词：crystal undulator field;Γ-klystron;short wavelength laser;gain factor2|1963|0更新时间：2025-07-16
- 摘要：In this paper,the relation between bisimplicial edges in a bipartite graph and their corresponding concepts are discussed,and some properties of reduced contexts and chordal bipartite graphs are investigated.Then,we apply the element elimination for a concept lattice to bipartite graph theory,and obtain a representation of chordal bipartite graphs.More precisely,we show that a bipartite graph is chordal bipartite graph if and only if there is a join and meet irreducible element elimination ordering with respect to its corresponding concept lattice.2|1271|2更新时间：2025-07-16
- 摘要：In the present paper,the regular FI algebras have been investigated again based on the idea of classical algebras.Firstly,in regular FI algebras the concept of the MT ideal is proposed by the implication operator,and the connections between MT ideals and congruence relations are discussed;Secondly,in regular FI algebras the prime MT ideals is defined,and the theorem of conditional embedding of regular FI regulars is gained by the prime MT ideals.Thirdly,the characteristic of MT ideals is described with the help of co-triangle-norm on regular FI algebras that is shown by the form of implication operators,and the generating method of MT ideals is given by the theorem of characteristic of MT ideals in regular FI algebras.关键词：logic algebra;regular FI algebra;MT ideal;congruence relation;reducibility;conditional embedding;generating method2|1242|10更新时间：2025-07-16
- 摘要：Survivability is widely regarded as one of the most critical components during the architecture migration of optical transport networks.This paper reviews the research achievements and the state-of-the-art progress in the field of optical network survivability,which includes connection recovery in optical networks,resource optimization and service quality in survivable optical networks,connection recovery in two-layer networks,and failure localization in transparent optical networks.关键词：optical transport networks;network survivability;resource optimization;quality of service (QoS);shared path protection;two-layer networks;failure localization2|1520|0更新时间：2025-07-16
- 摘要：In view of data intensive cloud computing applications,disk-based storage systems are difficult to meet their demand for performance and availability simultaneously.This paper puts forward a key-value distributed storage system named M-Cloud,which uses memory as main device and disk as auxiliary when providing storage services(read,write,backup and recovery)for big data.M-Cloud improves overall system performance by loading entire data in the memory of the cluster,and designs PBLH(partition-based linear hashing) algorithm to achieve load balancing and high scalability.M-Cloud also designs relative backup and fast crash recovery strategy in order to ensure high system reliability.The simulation results show that M-Cloud has high performance and availability,with further optimization,the system has the potential in real production environment usage,can provide users with high-quality storage services.关键词：cloud computing;key-value;distributed storage system;linear hashing;crash recovery5|2459|3更新时间：2025-07-16
- 摘要：In order to promote the understanding and evolution of a legacy software system,it is necessary to have an overall view of the structure.The common solution is to analyze the static source code by using clustering technique.In object-oriented software systems,however,due to the complexity of the software itself,such as exists of polymorphism and dynamic binding,and other factors,object's behavior actives need to be considered also.Use cases reflect the functionality of a system and play a key role in program comprehension.By clustering to establish the structural framework of the system,and by comparison with the actual design of the structure,our approach combines association rule mining techniques to obtain the mapping between use cases and corresponding events,and through the analysis of the static structure of use cases and related events invoked dependencies expansion.Finally,the experimental analysis of an open source project is evaluated and discussed to account for the applicability and effectiveness of our approach.关键词：dynamic analysis;static analysis;use case;clustering;software structural recovery2|1546|1更新时间：2025-07-16
- 摘要：According to the law of visual perception,this paper presents three elements to describe the outdoor scene image:ground,vertical objects,the sky,and gives the equations for outdoor scene image.Then proposes fast classification method for outdoor scene image based on independent image element function code.And mainly discusses the water light model in outdoor scene,analyzes the related physical properties,defines the water quality parameters,environmental dyeing parameters,independent image element function code,the mother image element and so on.Finally presents wild scene analysis method and water body identification technology by using data fusion algorithm.Experiments show that the method for the wide outdoor scene analysis and water bodies identification can get very good results.关键词：outdoor scene analysis;three scene elements;image element;independent image element function code;water body identification3|1384|2更新时间：2025-07-16
- 摘要：In order to solve the problem of nonlinear and nonstationary signal de-noising,a novel de-noising method is proposed by combining the principal component analysis(PCA) and empirical mode decomposition(EMD).The method removes noise of intrinsic mode functions(IMFs) using PCA,after the noisy signal is decomposed by EMD.Firstly,the signal details of the first IMF are extracted by using 3σ criterion,and the noise energy of each level IMF is estimated.Secondly,the PCA is implemented on each IMF,and the part of principle components are selected to reconstruct the IMF according to noise energy of IMFs,then the noise of IMF is removed efficiently.Numerical simulation and real data test were carried out to evaluate the performance of the proposed method.The experimental results showed that the proposed method outperformed the Bayesian wavelet threshold de-noising algorithm and mode cell EMD de-noising algorithm.So it is an effective signal de-noising method.关键词：empirical mode decomposition;signal de-noising;principal component analysis;noise energy2|2445|26更新时间：2025-07-16
- 摘要：This paper analyzes the stability and transient response enhancement limit of traditional LDO system and a transient response enhancement technique of on-chip LDO system is presented.Based on the analysis,a transient response enhancement technique fully integrated on-chip is put forward.The proposed scheme not only results in stability within a wide range of load variation,but also gets a good ripple rejection without off-chip capacitor and equivalent series resistor.It is demonstrated by simulation that the proposed circuit dissipates only 64μA of quiescent current with empty load and it is capable of delivering load current up to 800mA,the power supply rejection rate at 1KHz is about -60dB.For a load step of 800mA/5μs,the circuit has a maximum undershoot of 400mV and a maximum overshoot of 536mV.The recovery time is only 6.7μs and 12.8μs respectively and the layout area is about 0.64mm2.关键词：transient response;phase margin;quick response;low dropout;large loading current4|2635|2更新时间：2025-07-16
- 摘要：To deal with the problem of basic waveforms extraction in multifunction radar pulse train analysis,a new method is proposed based on statistic change point detection.Considering the discrete scan pattern of phased array antenna,the extraction of basic waveforms is converted into the detection of pulse amplitude change points.The circular binary segmentation algorithm which is used for biological chromosome analysis is introduced to split the pulse train into regions of equal amplitude,each of which corresponds to a certain basic waveform.The proposed method needs no prior knowledge,and can give a high performance even when the noise level is comparable with the change level of amplitude.Simulation results show that the method is applicable and effective.关键词：multifunction radar;statistic change points;circular binary segmentation algorithm;electronic warfare2|1416|8更新时间：2025-07-16
- 摘要：A level inference method for aggregated information of objects based on associated attributes is put forward in order to give a solution to information leakage caused by the association among objects.According to dependency relationships,highly associated objects are found,and then the probability of higher level information inferred by aggregation of associated objects is computed by probability estimates of fuzzy sets on secure level of attribute.The method may contribute to establish access control policy in multi-level secure network,and control restricted access of associated objects in order to reduce the risk on information system.关键词：MLS;classified security protection;object aggregation;inference channel;level inference2|1653|1更新时间：2025-07-16
- 摘要：This paper proposes an inverter gate delay model that is comprehensive for inverter gate delay analysis considering substrate coupling.The proposed model transforms the CMOS inverter delay to resistor and capacitance (RC) delay,and then computes the RC network delay under the process variation considering substrate coupling effect.The delay model analysis uses stochastic collocation methods combined with a polynomial chaos,which considers within-die process variation and substrate coupling effect.Experimental results are based on numerical calculation method.Simulation results show that the method’s proportional error is less than 2% compared to HSPICE simulation.关键词：process variation;inverter gate delay model;substrate coupling effect;polynomial chaos theory2|2222|1更新时间：2025-07-16
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