最新刊期
卷 39 ， 期 4 ， 2011
- 摘要：Current solutions on web services selection based on preferences mainly consider single user’s preferences,moreover,most of them are quantitative methods.However,many users propose different preferences on QoS attributes of web services in real applications.On the other hand,in many domains it is desirable to assess such preferences in a qualitative rather than quantitative way.This paper focuses on QoS-based qualitative service selection according to multi users’ preferences.We propose an algorithm based on CP-net.The algorithm can deal with Web service selection in terms of multi users’ preferences.Experimental results indicate that this method can obtain an optimal outcome which closely satisfies most users’ preferences and show the performance of the method.关键词：Web services;quality of services;CP-net;preference logic2|1373|3更新时间：2025-07-16
- 摘要：The paper brought forward and demonstrated a great engineering project:to build an Internet Information Broadcast-Storage System(IBSS).That is,packaging the excellent information on the Internet,sending them to the satellite periodically,broadcasting them to many local storage servers from the satellite,finally pushing them to the end users who have ordered them.关键词：scale-free network;broadcast-storage system;internet;culture diffusion;network convergence2|1365|2更新时间：2025-07-16
- 摘要：Recent work shows sink mobility can improve the energy efficiency in wireless sensor networks.However,the speed limit of the mobile sink often lead to increasing data gathering delay,which may be unacceptable in some real-time applications with strict delay requirement.To address this issue,this paper proposes a path selection scheme based on virtual nodes' priority to meet the delay requirement and minimize the energy consumption of entire network.Simulation experiments under MATLAB shows that computational complexity performance and scalability performance of the proposed scheme can be increased effectively at the cost of little more energy consumption in comparison with some baseline algorithms.关键词：delay-guaranteed;sensor networks;mobile sink;path selection2|1454|18更新时间：2025-07-16
- 摘要：In this paper,a QoS (quality of service) handover decision scheme with ABC (always best connected) supported is proposed.With knowledge of fuzzy mathematics and microeconomics introduced,application types,QoS requirements,access networks and terminals are described.With application QoS requirements,costs user willing to pay,user preferences to access network coding schemes,user preferences to access network providers,terminal velocities,terminal battery capacities and access network conditions considered comprehensively,an optimal handover solution of assigning N terminals to M access networks is found based on niche PSO (Particle Swarm Optimization) algorithm.With the help of gaming analysis,Pareto optimum under Nash equilibrium of user utility and network provider utility is achieved or approached for the found solution.Simulation results showed that the proposed scheme was effective.关键词：NGI (next generation Internet);access network;handover decision;ABC (always best connected);QoS (quality of service);Niche PSO (particle swarm optimization)2|1464|2更新时间：2025-07-16
- 摘要：Due to the ignorance of energy and security factors,traditional scheduling policies are not suitable for security-critical distributed embedded systems.A Security and Energy-Aware Task Mapping and Scheduling (SEATMS) algorithm is proposed for security and energy-critical distributed collaborative applications.The proposed algorithm can strive to reduce the security risk while without sacrificing the real-time and energy constraints,and was proved to be an algorithm with polynomial time complexity.Simulation results show superiority of SEATMS on real-time guarantee,energy budget guarantee,and low security risk.关键词：distribute embedded system;collaborative task;energy consumption;security risk;mapping and scheduling2|1743|1更新时间：2025-07-16
- 摘要：Traffic matrix estimation is an interesting research problem at present.Network operators use it to conduct load balancing,route optimization,traffic detecting,network dimensioning and so on.However,the highly ill-pose nature of traffic matrix estimation itself makes it being a challenging research subject to estimate accurately traffic matrix.This paper studies traffic matrix estimation in large-scale IP backbone networks.Based on RBF (radial basis function) neural network,a novel estimation method,namely TMRI (traffic matrix recurrence inference),is proposed.TMRI exploits the powerful modeling ability of RBF neural network to model traffic matrix estimation.The ill-pose nature of this problem will be overcome in the process of training the RBF neural network.Accordingly,the complex process of mathematic modeling can be avoided.Built on this estimation model,traffic matrix estimation is described into the optimal process under the constraints.By seeking the recurrent optimal solution,TMRI can further get rid of the ill-pose nature of this problem.Simulation results show that TMRI can accurately estimate traffic matrix and track its dynamics,and in contrast to previous methods,it holds the stronger robustness to noise and more evident performance improvement.关键词：traffic matrix estimation;nonstationary traffic;radial basis function (RBF) neural network;ill-posed nature;optimization2|2239|4更新时间：2025-07-16
- 摘要：This paper focuses on the quality of coverage (QoC) and connectivity problems for wireless sensor networks,considering the cooperative sensing model and the multi-adjustable communication rang without location information.For the random deployment policy,the performances of the network QoC and the network connectivity for various number of active nodes,different area of the monitored region and changeable performance parameter of each node are presented respectively.Furthermore,the scheduling control algorithm (SCA) is designed to guarantee the QoC and connectivity of networks with the least number of nodes.It chooses the uniformly-located working nodes and makes sure that the energy consumption of each node consumes homogeneously.Simulation results show that the active node number employed in the cooperative sensing model to provide the desired QoC of networks is less than that of the binary sensing model.And the SCA policy not only provides the desired QoC and connectivity of networks,but also reduces the total energy consumption and balances the energy dissipation among nodes.关键词：Wireless sensor networks;cooperative sensing model;quality of coverage (QoC);connectivity2|1510|20更新时间：2025-07-16
- 摘要：Two key problems in the asynchronous space-time cooperative transmission systems are the loss of OSTBC’s orthogonality and the channel dispersion,which may prevent the direct use of OSTBC and lead to severe performance degradation.To solve these problems,this paper proposes a new cooperative transmission scheme based on SC-FDE.Adopting the idea of OSTBC,simple operations such as reversal and conjugation are performed on the transmitting data at each relay node.The destination node performs FFT on the receiving data,then separates the superimposed frames by linear combination.The outputs of the combination are equalized by a frequency domain equalizer.At last IFFT is performed on the equalized data to recover the original data.By using FFT and IFFT,the new scheme has low complexity.Theoretic analysis and simulation results show that the new scheme can achieve diversity gain supplied by OSTBC even without perfect synchronization.关键词：asynchronous cooperative transmission;orthogonal space time block coding (OSTBC);single carrier frequency domain equalization (SC-FDE);diversity gain2|1261|0更新时间：2025-07-16
- 摘要：The main focus of this paper is to investigate the system downlink outage probability in distributed antenna systems (DAS).Firstly,this paper establishes a composite channel model which takes into account three factors such as path loss,lognormal shadowing and Rayleigh fading.Then,by making use of the moment generating function (MGF),this paper derives the probability density function (PDF) of the output signal-to-noise ratio (SNR) after maximal ratio combining (MRC) at the receiver.After that,an approximate analytical expression of the outage probability for a mobile station (MS) over a given position is derived with an antenna selective transmission (ST) scheme.Further,considering the distribution of MSs in the system,a closed-form expression of the system outage probability is obtained.Numerical results show that the closed-form expression can provide sufficient precision for evaluating the outage probability performance of DAS.关键词：distributed antenna systems;system outage probability;maximal ratio combining;selective transmission;composite channel2|1379|2更新时间：2025-07-16
- 摘要：In wireless sensor networks (WSNs),energy hole problem is a key factor for affecting the lifetime of networks.In a circular multi-hop sensor network (modeled as concentric coronas),the optimal transmission ranges of all coronas can effectively improve system lifetime.For the WSN with non-uniform data generating rate,an energy-efficient algorithm for non-uniform data generating rate (EANR) can search approximate optimal transmission ranges of all coronas in order to prolong network lifetime by constructing coronas relationship table.EANR can reduce the searching complexity and get results approximated to the optimal solution.The simulation results indicate that the lifetime got from EANR approximates to the lifetime from the optimal list.Compared with the algorithms in other literatures,EANR can prolong the network lifetime.关键词：wireless sensor network (WSN);energy hole problem;multi-objective optimization problem (MOP)2|978|1更新时间：2025-07-16
- 摘要：In this paper,A construction of shift sequence sets is presented,based on these shift sequence sets one can get many cyclically distinct zero-correlation zone (ZCZ) or low-correlation zone (LCZ) sequence sets by utilizing interleaving technique.Compared with previous constructions,the present method can provide more spread-spectrum sequences for quasi-synchronous CDMA (QS-CDMA) systems.More than that,mutually orthogonal sets of zero-correlation zone sequences are also constructed based on these shift sequence sets.关键词：quasi-synchronous CDMA (QS-CDMA);interleaving technique;shift sequence;zero-correlation zone or low-correlation zone (ZCZ/LCZ);mutually orthogonal2|1159|8更新时间：2025-07-16
- 摘要：In a wireless multiple-input multiple-output (MIMO) system,transmit antenna selection is an effective means of achieving good performance with low complexity.However,the space for the antenna array is usually limited on wireless terminal.Hence,antenna’s configurable pattern selection is considered to save space,using spatial multiplexing with linear receivers,and equal power and equal rate allocation to reduce feedback overhead.Under these constraints,a statistical adaptive transmit antenna pattern selection is studied to improve the capacity of spatially correlated MIMO fading channels.Then,we propose a fast transmit antenna pattern subset selection criterion based on maximizing this average lower-bound capacity.More over,in order to catch up the channel variant in low speed moving environment in a real transceiver,we also propose a refreshed gradient estimation method based on sliding time window.And the measured result indicates that the method reduces the searching time of reconfigurable patterns selection.关键词：antenna selection;reconfigurable patterns;sliding time window;MIMO2|1292|1更新时间：2025-07-16
- 摘要：A novel despeckling method for medical ultrasound images is proposed based on quantum-inspired parameters estimation.A new probability distribution function with an adaptive parameter is built up with the modelling of log-transformed medical ultrasound images coefficients.Considering the inter-scale dependency of coefficients,the quantum-inspired probability of signal and noise is firstly introduced based on the normalized products of the coefficients and their parents.Using the Bayesian estimation theory,an adaptive shrinkage function is proposed based on quantum-inspired parameters estimation.Experiments showed that our method can notably reduce speckle noise and preserve details of medical ultrasound image effectively,which achieved much better performance than that of the other related despeckling methods.关键词：despeckling;quantum signal processing;dual-tree complex wavelet transform2|1460|4更新时间：2025-07-16
- 摘要：A method for ECG de-noising based on Hilbert-Huang Transform has been proposed.ECG was analyzed by the Hilbert spectrum of the IMF,which was produced by the Empirical mode decomposition method.The three main noises were respectively removed according to the characteristics of noises.Power line interference and high frequency noises were mainly mixed into the low IMF of ECG,while baseline wander noises were mainly mixed into the high IMF.The morphological filter method based on adaptive threshold was used in the low IMF for de-noising,while baseline wander was estimated by the smooth filter in the high IMF of ECG.The results of simulation experiment and practical application demonstrate that the method proposed in this paper performs better than wavelet de-noising method significantly,not only in suppressing the three mainly noises effectively,but also in preserving the primary characteristics of ECG signal.关键词：Hilbert-Huang transform;empirical mode decomposition;intrinsic mode function;ECG;de-noising;morphological filter2|1973|12更新时间：2025-07-16
- 摘要：A modified marker-extraction based watershed algorithm was proposed in this paper to deal with the over-segmentation during color image segmentation.The modified algorithm was constituted of smooth filtering,color gradient calculation,marker-extraction and watershed transformation.During smooth filtering,a novel spectrum envelope filter was designed.The new filter had a better performance on edge-preserving which was used to smooth the imported color image and gradient image.The color gradient was calculated right in the color vector space.During the course of marker-extraction,H-minima transformation was used to extract minima-marker in smoothed gradient image firstly,whose parameter was adaptively controlled by the depth information of local minima region.Then,the extracted minima-marker was updated by more information of local minima region.Finally,the updated minima-marker was imposed on the original gradient image to get the marked gradient.The final result was gotten from the watershed transformation on the marked gradient.The experimental results indicate that the modified algorithm overcomes the difficulties in getting accurate edges and detecting weak edges.Furthermore,it has a more reasonable initialization rule of parameters and a better adaptability.关键词：color image segmentation;smooth filtering;watershed;marker-extraction2|1977|10更新时间：2025-07-16
- 摘要：A novel contour function,Arc-Height Radius Complex function (AHRC),is proposed for shape description.AHRC captures the global feature and local detail information of the shape through extracting the centroid distance and signed arc-height features from the shape contour.The Fourier coefficients of AHRC are utilized to construct the feature vector for shape description.The performance of the proposed method is evaluated on the standard MPEG-7 shape database and the leaf shape database which is captured from the real world.The experimental results of image retrieval show that the proposed method outperforms the other Fourier descriptors including centroid distance,triangle area,farther-point distance,angle radius and wavelet Fourier descriptors.关键词：image retrieval;shape description;Fourier descriptors;arc-height radius complex function2|1215|5更新时间：2025-07-16
- 摘要：A new concept 'Factor Analysis technique’ for array processing is introduced in this paper.The model which Factor Analysis considers closely resembles the data model received by array.So the properties of it have been proven useful to estimate the source numbers for DOA estimation.This paper presents the algorithmic approach of least square criterion to estimate the source number and spatially colored noise from the covariance matrix of received signals based on Factor Analysis model.The estimation performance is illustrated by computer simulation with comparisons to traditional methods.关键词：factor analysis;least square;estimation of source number;colored noise2|1347|3更新时间：2025-07-16
- 摘要：According to the demand of maximum Doppler shift estimation under the urban complex channel environment,a novel maximum Doppler estimation is proposed based on noise matching.Through a low-pass filter designed (LPF) to filter the received signal,interference noise and the Doppler detector can be matched,thus the estimation performance of the maximum Doppler shift is increased effectively.Furthermore,by theoretical deduction of the best filtering ratio in Rice fading channel,two important deductions about the estimated error of proposed algorithm are presented.Monte-Carlo simulation results show that compared with the existing algorithms based on logarithmic envelope (LE) and modified covariance (MCOV),the proposed algorithm improves estimation performance by 2~5dB under the typical urban environment and low signal-noise-ratio (SNR<0dB) conditions.Therefore,proposed algorithm can ensure an accurate estimation of maximum Doppler shift and the receiving performance of mobile communication systems.关键词：maximum Doppler shift;Rice fading channel;noise matching2|1394|1更新时间：2025-07-16
- 摘要：To realize the function of the synthetic aperture radar (SAR) image and ground moving target indication (GMTI),the along-track array is the best configuration for the distributed small satellites.However,array errors significantly degrade the performances.An estimation method based on the data in compressed range time and azimuth Doppler domain is given.In the proposed method,the range pulse compression is used to improve the signal to noise ratio.And the gain error is corrected before the other error estimations which avoids the interaction between the gain error and the along-track position error.Computer simulations show that the convergence rate of the proposed method is quickened with the estimate accuracy improved,compared with the conventional method.关键词：distributed small satellites;ground moving target indicator;synthetic aperture radar;error calibration2|1177|0更新时间：2025-07-16
- 摘要：Aiming at the problem of underdetermined blind separation of the attenuated and delayed mixtures,we propose a method based on the subspace decomposition to find the single source area in time-frequency domain,and then estimate the mixing matrix via clustering the principal eigenvectors of the covariance matrixes corresponding to the single source regions without knowing the number of original sources,finally we modify the algorithm based on subspace projection to extract the original signal.Simulation results indicate that the proposed algorithm estimates the mixing matrix with higher accuracy and separates the source signals with higher gain,compared to the other algorithms关键词：underdetermined blind separation;attenuated and delayed mixtures;non-stationary signals;single source region detection3|1477|4更新时间：2025-07-16
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A Joint Source/Channel Coding with Reduced Trellis Algorithm for the Scalable Extension of H.264/AVC
摘要：In this paper,a joint source/channel coding (JSCC) video transmission approach is proposed for the scalable extension of H.264/AVC coding (SVC) standard.The JSCC approach employs a novel reduced trellis algorithm and Lagrangian optimization technique to derive appropriate parts of the SVC stream and protection levels of error-control codes.The proposed algorithm uses a discrete trellis structure.With the layer-based computation method and a simplified structure,it improves computation efficiency by about 20-50 times over the state-of-the-art algorithm.Extensive simulation results show that the proposed JSCC scheme with the efficient algorithm provides same optimized performance with other algorithms under various channel conditions.关键词：scalable video coding (SVC);joint source/channel coding;H.264/AVC;video transmission2|1081|2更新时间：2025-07-16 - 摘要：Elliptic curve scalar multiplication is a basic operation of elliptic curve cryptosystem.Secure and efficient scalar multiplication algorithm will directly promote efficiency and security of elliptic curve cryptosystem.In this paper,the concept of Fibonacci series is extended and proposed,which is used to simplify point addition formula on Montgomery-Form elliptic curve and to get a new point addition formula fibAdd.The Fibonacci-type series of any positive integer k is computed by using Golden Ratio Addition Chain method.By combing of both methods,the paper constructs an efficient and secure scalar multiplication algorithm for any given integer k on Montgomery-Form elliptic curve is constructed.This new algorithm is 23% faster than GRAC-258 and is 39% faster than EAC-320 in the best case.Also,because the algorithm performs only point addition operation,and there is no need for doubling operation,it possesses naturally the ability to resist side channel attack.关键词：scalar multiplication;montgomery-form elliptic curve;golden ratio addition chain2|1251|2更新时间：2025-07-16
- 摘要：Kim et al.determined the trace function representation of Legendre sequences with prime period p≡3 or -3 (mod 8) by using two different primitive elements of the finite field GF(2^n).In this correspondence,firstly,the authors divide the group GF(p)* into the union of cosets of subgroup generated by 4.Then,they propose a new trace function representation of Legendre sequences via the trace function from the finite field GF(2^n) to its subfield GF(4).The trace representation is described only using one primitive element of the finite field GF(2^n).It has positive effect to the computational implementation of Legendre sequences.关键词：Legendre sequences;trace function;linear complexity2|964|2更新时间：2025-07-16
- 摘要：Consensus of mobile multi-agents system with heterogeneous communication delays and heterogeneous input delays is studied.Suppose multi-agent systems consist of n agents and a leader,there is an asymmetric directed interconnected graph with leader as a globally reachable node.By Appling frequency domain theory and generalized Nyquist criterion,the consensus of delayed algorithm with leader-following is analyzed,and a decentralized convergence condition is obtained to ensure the consensus of multi-agent systems.This consensus condition is dependent on input delays but independent of communication delays.Finally,computer simulation is used to show the validity of the results.关键词：heterogeneous delays;leader;multi-agent systems;asymmetric topology;decentralized;consensus condition14|2061|15更新时间：2025-07-16
- 摘要：Standard Bloom Filters needs to know the number of different elements in data set in order to determine the optimal number of hash functions.However,the data distribution information is not easy to obtain prior.This paper proposes a multi-stage dynamic optimization for Bloom Filters hash functions number (MDBF).It splits element insertion procedure into several stages,and in each stage of element insertion,MDBF decides the optimal hash function number by analyzing the inserted data distribution with bit vector usage situation.The experimental results show that MDBF can select the optimal number of hash functions to obtain low false positive probability in complicated applications,which have element multiplicity and skewed distribution.关键词：bloom filters;hash function;skewed distribution;false positive probability3|1145|1更新时间：2025-07-16
- 摘要：Ontology mapping plays a key role in semantic integration area,a top-down ontology mapping method is proposed by this paper,it considering four basic mapping and this mapping process is assumed that all cases are 1:1.This approach describes the ontology as a graph and each ontology concept defined as a tree,on the basis of the tree,give the similarity computation method of leaf nodes and non-leaf nodes,merge the concept sub-tree by concept classification,According to the results of classification re-organization ontology chart structure.Finally,give a complete ontology mapping model.If the number of ontology is greater than two,concept of group separation method will be used,that is,a similar ontology in the same group,no similar in a different group,the separation date until convergence.Experimental results show that the layer classification ontology mapping method can reduce non-related concepts among count for large scale structure ontology mapping for the efficiency and accuracy it achieve the desired results.关键词：semantic web;ontology mapping;classification;similarity computation2|1055|1更新时间：2025-07-16
- 摘要：At present,various hardware architectures coexist,traditional parallel component resource management can not fully take advantage of parallel component properties to meet the diversity of the underlying hardware.At the same time the scalability of traditional parallel component is rather poor.In this paper,the research based on the specifications of CCA proposes a hierarchical model for parallel component resource management,then this paper mainly proposes the resource selection algorithm based on dynamic programming.Experimental results show that related to the tactics of CPU frequency priority,CPU Cache value priority and communication priority,the resource selection algorithm based on dynamic programming can select the resource of computing node more precise,and has a good scalability.关键词：parallel component;resource management;hierarchical model;dynamic programming2|1099|1更新时间：2025-07-16
- 摘要：Stream data are generated unboundedly,coping with the conflicts commendably between data processing power and flow velocity may require mining system to provide a more effective solution for Data Stream Sampling.This paper proposed a logical sliding window named ring circular sliding window based on a ring buffer and these two elements were tightly coupled.Then an algorithm for data stream sampling based on ring circular sliding window was proposed.Experimental results show that it is a data stream sampling model which is proper for the migration and mining of data stream,and can achieve further improvement on the speed of data stream sampling and ensure normal execution of data stream mining.关键词：data stream;ring circular sliding window (RCSW);ring buffer;simultaneous multithreading (SMT)2|1537|4更新时间：2025-07-16
- 摘要：The method for proposing sub-normed Z-linear space has been applied to investigate the structure of classical logic metric space ([F(S)], ρ). A class of isometric transformations in ([F(S)], ρ) are formed and it is proved that these isometric transformations constitute a group,and the space ([F(S)], ρ) thereby make a sub-normed Z-linear space with a modular 2 additive structure.Moreover,it is clarified that the space ([F(S)], ρ) is isomorphic to the normable linear space on the finite field F(2),and relations among norm,truth degree and metric are obtained.关键词：logic metric space;translation group;sub-normed Z-linear space;truth degree;normable linear space on the finite field F(2)2|1167|2更新时间：2025-07-16
- 摘要：The life cycle and network characteristics of p2p botnet was analyzed,improved sprint method and similarity function was discussed and new online detect approach was proposed.Secondly,the virtual machine network environment,the design of prototype system and the analysis of the experiment result was discussed.The result shows that the detection approach is feasible,high efficient and reliable.关键词：botnet;P2P network;detect2|1135|4更新时间：2025-07-16
- 摘要：Burst mode scheme and azimuth beam steering lead to the aliasing phenomenon of TOPSAR data existing in both the Doppler frequency and the azimuth output time domain.The "full-aperture" imaging approach with up-sampling operation in both azimuth time and frequency domain can overcome the aliasing problem.However,it brings an unwanted result of seriously increased computational complexity and memory consumption.Based on the special spaceborne TOPSAR raw data support in the slow time/frequency domain (TFD),a new imaging approach combined with azimuth scaling operation and chirp scaling algorithm (CSA) is proposed in this paper.In this approach,sub-aperture formation and recombination are avoided and the sawtoothed azimuth antenna pattern correction can be easily implemented.As azimuth data extension in the output time domain in not required,efficiency of the presented algorithm is seriously improved.Simulation results of point and distributed targets validate the presented algorithm.关键词：TOPSAR (terrain observation by progressive scans);burst mode;aliasing;antenna pattern correction;chirp scaling algorithm2|1311|6更新时间：2025-07-16
- 摘要：Over the past decade,Peer-to-Peer (P2P) media streaming technology,as a promising solution for large-scale media streaming,has always been of a great research interest for both the academia and industrial communities,and a great variety of P2P streaming systems have been developed and widely deployed on the Internet.In this paper,we present a comprehensive and in-depth survey of existing typical P2P streaming systems,in which the core technologies,including overlay network construction and data scheduling mechanism,are detailed introduced and analyzed.We also briefly discuss the enhancement technologies such as video coding,network coding,overlay network topology optimization,and security and incentive mechanisms.Performances of several typical P2P streaming systems are also compared.Finally,we point out the open issues and challenges in P2P streaming research and comment on possible future research directions.关键词：peer-to-peer;media streaming;P2P live streaming;P2P video-on-demand2|3386|3更新时间：2025-07-16
- 摘要：By introducing constraint semiring as description domain,a trustworthiness evaluation method for atom and composite service is proposed.The evaluation method for the multiple trustworthy dimensions of atom services is put forward,followed by the criteria that evaluate the trustworthiness of composite services based on structured process model.We use utility functions to compute the normalized value and compute the weights based on fuzzy matrix that computes the overall trustworthiness score of a service with weighted sum.Demonstrative examples reveal the effectiveness of the proposed methods.关键词：semiring;service;trustworthiness2|1056|2更新时间：2025-07-16
- 摘要：The Trust Computing Group Specifications specify all components running on the trusted computing platform should be trusted,which seriously restrained the applications of trusted computing platform.This paper proposes a trusted terminal computer model tolerating untrusted components.Comparing with the existing trusted platforms,the model allows untrusted components loading and assures the security results be expected and controlled.The model includes trusted domains and untrusted domains tolerating untrusted components.With the non-interference theory,an untrusted component-tolerating mechanism is designed and reasons out the sufficient conditions about the trusted domain can run trustfully.Based on the theory model,provides a detailed physical model and proves it be a trusted terminal computer model.关键词：trusted terminal model;untrusted components;non-interference;embedded trusted system2|1239|5更新时间：2025-07-16
- 摘要：Elimination criteria based on mean value,variance and norm was often used in the VQ encoding to reject unlikely codewords.However,these elimination criteria have obvious computational redundancy.A new elimination criteria based on triangular inequality in subspace was proposed.By finding the optimal reference point of distance computation,the new elimination criteria can reject more unlikely codewords than other elimination criteria using variance and norm.The elimination criteria based on variance can be seen as the special case of new elimination criteria.Before the search process,all codewords in the codebook are Hadamard-transformed and sorted in the ascending order of their first elements.During the search process,the mean value of a vector was used to terminate the search process,and the new elimination criteria based on triangular inequality in subspace was applied to reject most unlikely codewords.Experiments results demonstrate that the performance of the proposed algorithm is much better than other nearest neighbor codeword search algorithms.Compared with the Hadamard-Transformed based Equal-Average Equal-variance Equal-norm Nearest Neighbor Search algorithm,the proposed algorithm reduces the computational time by 8% to 26%.关键词：vector quantization;codeword search;subspace;triangle inequality2|1165|1更新时间：2025-07-16
- 摘要：Almost all of the multi-objective optimization evolutionary algorithms(MOEAs) are designed for the Pareto optimal front which is distributed uniformly.But in real world optimizations,the Pareto optimal front usually has a non-uniform distribution.A similar solution set distribution with Pareto optimal front is expected to obtain by decision makers.However,the existing algorithms cannot solve such problems effectively.In this paper,a diversity maintenance method for non-uniformly distributed multi-objective optimization problem(NUDMM) is proposed.In the algorithm,an indicator reflecting 'regular’ degree of distribution-Messy is defined.And a method to decrease Messy of population is designed,which eliminates disordered individual on the condition that the distribution of the Pareto optimal front is unknown.From an extensive comparative study with NSGA-II and SPEA2 on eight non-uniform distribution test problems,it is observed that the proposed method has a good performance in maintaining the real distribution and convergence.关键词：multi-objective optimization;multi-objective evolutionary algorithms;diversity maintenance;non-uniform distribution;test problem;messy2|1273|4更新时间：2025-07-16
- 摘要：For the inadequate training speech data of speaker identification based on short utterance,feature vectors and GMM models are optimized and improved,an efficient GMM based on local PCA with fuzzy clustering is presented.To compensate for the limited feature samples,the effective feature dimensions are increased with feature combinations instead of single feature.Furthermore,the time and space complexity of the system can be compressed by reducing dimensions of feature combinations with local fuzzy PCA in the premise of little effect on recognition rate.Finally,a new approach which combines division and fuzzy k-means clustering is used,in order to optimize GMM initialization parameters.The experiments show that the improved method is more effective in improving performance of the system than traditional initialization methods.关键词：speaker identification;short utterance;local fuzzy principal component analysis;combined division and fuzzy k-means clustering2|1330|5更新时间：2025-07-16
- 摘要：There will be non-ideal iris images when the person is moving at a normal walking pace through an iris capture device.An iris localization method based on elliptical projection is proposed,which solved the localization problem of non-ideal off-angle iris images.Firstly,relative position between two eyes is calculated to determine the rotation angle of the head.Then a point within pupil is easily found.Starting from that point,iris inner boundary points are searched according to gradient variation.An elliptical inner boundary is fit using the least squares.Secondly,eye gaze direction is detected by the circularity of ellipse,and an off-angle iris image is converted into a frontal view iris image adopting projection transform.Thirdly,iris outer boundary points are searched using the boundary point optimal selection method in the frontal view iris images,and outer boundary is located by the means of three points fitting a circle.Experimental results show that the proposed algorithm can effectively locate off-angle iris in a very short time.关键词：biometrics;iris localization;non-ideal iris;ellipse;projection transform2|1247|1更新时间：2025-07-16
- 摘要：When the compound-Gaussian clutter can be clustered into groups of data with one and the same value of the texture,the Constant False Alarm Rate (CFAR) property and the detection performance of the adaptive normalized matched filter (ANMF) are analyzed in the mismatch situation,where the estimated clutter group size is unequal to the actual one.The theoretical analyses show that,the ANMF holds fully CFAR property when the actual clutter group size is multiples of the estimated one,while it is only CFAR to the clutter covariance matrix structure for other cases.It also shows that,the ANMF holds almost CFAR property for different subsets.Moreover,different mismatch cases cause different performance loss for the ANMF;and the worst performance results from the case when no a priori information about the texture correlation is available at all.关键词：adaptive target detection;performance evaluation;covariance matrix estimate;constant false alarm rate;compound-Gaussian clutter2|1067|2更新时间：2025-07-16
- 摘要：Reference to the probability model of information transmission,a new estimation of distribution algorithm is proposed for non numerical optimization problems.Firstly,an updating model of a priori knowledge probability is built according to the superior information produced during evolution process,and the model of conditional transfer probability is also constructed based on the emerging frequencies of neighboring symbols.Secondly,the model of posterior probability is given by combining the above mentioned probability model to guide new population generating.Finally the presented approach is tested on TSP problems,and the results show that the proposed algorithm can improve the premature convergence of estimation of distribution algorithms.关键词：estimation of distribution algorithms;information transmission;posterior probability;TSP2|1140|2更新时间：2025-07-16
- 摘要：To solve the optimal path planning problem of mobile robots,a novel mobile robot path planning strategy based on fuzzy algorithm has been proposed.The environment situation has been detected using ultrasonic sensors to obtain the information about obstacles and goals.Fuzzy the position informations about obstacles and goals through fuzzy reasoning and establish the fuzzy rules.By defuzzification could make the mobile robot avoid obstacles successfully and find the optimal path.The simulation experiment results have shown that the fuzzy algorithm mentioned above is superior to potential field method and the A* algorithm with more effectiveness and feasibility.关键词：mobile robot;fuzzy control;defuzzification;path planning2|3744|21更新时间：2025-07-16
- 摘要：Aiming at the contradiction between the convergence rate and mean square error of traditional Constant Modulus Algorithm (CMA),a hybrid wavelet neural network blind equalization algorithm based on fuzzy neural network controlling (FHWNN) is proposed.In this proposed algorithm,a transversal filter is cascaded to the front end of the wavelet network input layer,outputs of the transversal filter nodes are divided into real and imaginary parts,these two parts signals are merged into one complex signal after passing wavelet network.The proposed algorithm can improve the control precision of step-size via using fuzzy rules of Fuzzy Neural Network (FNN) to control the step-size of scale factor and displacement factor of the WNN.The weight coefficients iterative formulas of the transversal filter and the wavelet neural network are obtained via constant modulus cost function.The theory analysis and simulation result demonstrate that the proposed algorithm has faster convergence rate and smaller steady-state error.Accordingly,it can overcome the contradiction between the convergence rate and mean square error effectively.关键词：blind equalization;underwater acoustic channels;complex system;fuzzy controlling;hybrid wavelet neural network3|1455|9更新时间：2025-07-16
- 摘要：It is regarded generally according to VLF theory that the capacitance of T model multiple tuned VLF antenna will increase pro rata by the number of antenna groups,five or six groups are adopted usually.We analysed the equivalent capacitance and inductance by the metrical reactance of T model VLF single tuned VLF antenna and multiple tuned VLF antenna,and studyed the relationship of its' equivalent capacitance,inductance,power capacity to its' frequency and antenna groups.The result shows that the capacity of each antenna group decreases gradually if the number of T model multiple tuned VLF antenna groups are overabundance,in fact the effect is limited to improve the power capacity and bandwidth when the antenna groups are more than three,it is an important guidance in the design of T model VLF multiple tuned transmit antenna.关键词：multiple tuned VLF transmit antenna;power capacity;equivalent capacitance;bandwidth2|1631|1更新时间：2025-07-16
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