最新刊期
卷 37 ， 期 11 ， 2009
- 摘要：Any mistaken maintenance for the complicated and distributed Grid can bring unpredictable disaster.Here we focus on the system availability problems caused by service dependencies during the maintenance in Grid.A novel mechanism is proposed in this paper.It provides multiple granularities (service-,container-,and node-level) maintenance for service components in Grid.By using the Cobweb Guardian,administrators of Grid can execute the maintaining task safely in runtime with high availability.The evaluating results show that our proposed dependency-aware maintenance can make the management for Grid more automatic and available.关键词：grid service;service dependency;service maintenance2|1086|0更新时间：2025-07-16
- 摘要：Load-balanced Split Aggregated Flow (LB-SAF) scheme was proposed for two-stage load-balanced self-routing switching structures.By grouping the signal lines with self-routing concentrators,this scheme obtained statistical multiplex gain and reduced the computing complexity for call admission control;moreover,optimal buffer design at line group of each stage achieved wire-speed forwarding and reduced the buffer complexity.Mathematical analysis and simulations show that it can guarantee 100% throughput for any admissible traffic pattern.Compared with other previous proposed schemes,LB-SFA has properties such as lower buffer complexity of O(N) and small constant queuing delay of O(1).These advantages make it more suitable for very large scale switching structures in Next Generation Network (NGN).关键词：buffer;load balancing;self-routing;large scale switch2|1198|0更新时间：2025-07-16
- 摘要：This paper presents a novel multicast algorithm in Peer-to-Peer (P2P) networks,which can restrain the selfish and malicious actions of P2P nodes using the multi-bids auction mechanism.This paper also discusses the distributed multicast protocol to ensure that the algorithm proposed will operate normally in the highly dynamic network environment.Simulation results demonstrate the effectiveness and reliability of the proposed protocol.关键词：peer-to-peer network;multicast;multi-bids auction;node;strategy2|919|0更新时间：2025-07-16
- 摘要：The security of cryptographic implementations with respect to "physical observation attacks" named side-channel attacks,in which adversaries are enhanced with the possibility to exploit physical leakages such as power consumption or electromagnetic radiation.A lot of countermeasures have been experimented,but do not fundamentally prevent them.In this paper,DES is implemented on AT89C52.DPA and countermeasure experiments have been done on this platform.Physically Observable cryptography is built by Micali and Reyzin who initiated a theoretical analysis of side-channels.Our work is to apply the "Physical-Observation" attacks to practice for Symmetric Encryption schemes and find out how it is applied to DES-DPA attack practice for Symmetric Encryption schemes with random oracle model.关键词：data encryption standard(DES);differential power analysis(DPA);random oracle model;provable security;side-channel analysis;physical observable cryptography2|1542|4更新时间：2025-07-16
- 摘要：This paper indicates that Burmester et al.’s group key agreement protocol which based on the authenticated broadcast channel is unable to withstand the disruption attack and key-control attack of malicious participants in group.These two attacks lead that other honest participants will compute different session key and other honest participants compute the fixed session key which is determined previously by malicious participants,respectively.In this paper,a fault-tolerant group key agreement (FT-GKA) protocol is proposed.Even if there are malicious participants trying to attack the establishment of a session key,all other honest participants following the proposed protocol are still able to compute the correct session key using the digital signature technology.Paper proves the protocol can withstand the passive attack of adversary under the DDH assumption,and the protocol can withstand the interrupted attack and key-control attack from malicious participants under the DL assumption and the random oracle model.Furthermore,the proposed protocol possesses both constant number of rounds and lower computation overhead.关键词：group key agreement;interrupted attack;key-control attack;fault-tolerant;random oracle model2|1093|1更新时间：2025-07-16
- 摘要：This paper proposes a method to embed data in binary images with high embedding capacity.It is proved that,given an m×n image block of the host image,the upper bound of the amount of bits that can be embedded in that block is?(log2(mn+1)」by changing at most 1 pixel in the block.An algorithm whose embedding capacity can reach the bound is then constructed.We also summarize some rules for selecting pixels to be changed in order to maintain higher quality of the host image after data hiding.The robustness and security of the proposed algorithm is analyzed.Three examples,data hiding in digital handwritten signature,temper detection of digital binary documents,and invisible annotation for cartoon image are tested to illustrate the potential applications.关键词：data hiding;digital watermarking;image authentication;binary image2|1068|9更新时间：2025-07-16
- 摘要：A method for establishing the attack group model by means of the relationship graph of various attacks has been proposed.Under the constraints of time characteristics as well as the causality relation it can determine the attack sequence and reconstruct the attack sequence of the cooperative intrusion.Beside,make a timely response without considering the ratio of damage cost and response cost of the individual attack,so as to achieve the maximal reduction of the response cost.关键词：intrusion response;cooperative intrusions;attack group;attack relationship graphs;Minimal dominating set2|1103|2更新时间：2025-07-16
- 摘要：Most existing network motif discovery algorithms detect exact motifs.Because biological networks are incomplete and noise,and the life process is dynamic,probability network motifs are of great importance.In this paper,we propose a non-treelike network motif discovery algorithm,which focuses on network motifs derived from families of mutually similar but not necessarily identical patterns.In our approach,we first present a subgraph mining algorithm ESN for searching all non-treelike subgraphs of a given size.Then multiple graph alignment is performed on a set of subgraphs with a same size.Finally,a simulated annealing algorithm is used to derive network motifs,based on a statistical model and its corresponding scoring function.Experimental evaluation on transcriptional regulatory networks of E.coli and Yeast shows that our algorithm achieves good performance.关键词：biological networks;probability network motifs;subgraph mining4|861|3更新时间：2025-07-16
- 摘要：According to multi-source information coupling and the conditional quality of the system,topology contravariant theory is applied to the complicated system of multi-source information analysis,topology contravariant relations were designed and the result can be expected to be of describing complicated multi-source information,evaluating character,dynamic analysis.The new method was laid the foundation of expressing complicated system of multi-source information and intellectual monitoring and control in running.Using the technique to the machining manipulator system,dynamic state of manipulator was monitored accurately.Precision was founded and the theory was tested.关键词：complicated system;multi-source information;topology contravariant;manipulator2|1119|2更新时间：2025-07-16
- 摘要：An approach for Knowledge Acquisition from decision tables containing Continuous-Valued Attributes (KACVA) is developed.The equivalence partition in the classical rough sets theory is converted into a similarity partition.A novel representation method of the positive region in decision tables with continuous-valued attributes is built.Through calculating classification abilities of each conditional cluster to decision classes,decision rules in decision tables containing continuous-valued attributes are generated.Experimental evaluation on different data sets shows that the KACVA algorithm has the better performance in the classification accuracy comparing with the knowledge acquisition approaches under classical rough sets theory and the decision tree approach,C4.5,in processing decision tables with continuous-valued attributes.关键词：rough sets;attribute reduction;Knowledge acquisition;discretization2|1545|9更新时间：2025-07-16
- 摘要：Heatsink is often used to cool the chip which works in high frequency and high power.However,in high frequency environment,the heatsink becomes the main electromagnetic radiation source.Because the EMC capacity of system is decreased due to the heatsink,it is necessary to study the characteristics of heatsink electromagnetic radiation.In the paper,the vector FEM for heatsink is firstly introduced based on electromagnetic field theory.Then the characteristics of heatsink electromagnetic radiation are analyzed by the aspects of grounding methods,number and thickness of cooling fins changes,height of cooling fin changes.The key factors which affect the resonant frequency and the design notes of heatsink are presented.As the simulation results show,the power of electromagnetic radiation can be decreased and the resonant frequency can be improved effectively through selecting reasonable grounding method,the number and thickness of cooling fins changes have little effects on the resonant frequency and power of electromagnetic radiation,however,the power of electromagnetic radiation is impacted remarkably by the height of cooling fin changes.关键词：vector FEM;heatsink;cooling fin;electromagnetic radiation;scattering parameter2|1036|2更新时间：2025-07-16
- 摘要：The electronic tunneling process in a molecular device consisting of a composite symmetric multiple potential barriers in series is modeled by a simplified successive tunneling model.Patterns of the low-bias conductance of a molecule are inferred by the changing patterns of electronic transmission spectra with variations of the width,height of the barrier,the distance of the two neighboring barriers,and the efficient mass of electron.It is found that the low-bias conductance of a molecule decreases remarkably with an increase in either the width or height of a barrier,instead the low-bias conductance of a molecule increases substantially with an increase in either the distance of the two neighboring barriers or the efficient mass of electron.The results presented here suggest that the transport behaviors of molecular electronic devices under a low bias can be greatly modified in a controlled way (for example,altering the constituents or/and configurations of a composite molecule).关键词：molecular device;symmetric potential barrier model;electronic transmission spectrum;low-biased conductance2|1026|0更新时间：2025-07-16
- 摘要：A novel iterative algorithm base d on eight channel filter bank to estimate single-frequency is proposed.A highly overlapped filter bank is adopted in the proposed method to extend frequency estimation arrange and increasing SNR in single channel.By exploiting filter and decimation,the iterative algorithm is applied.Through this way the computational complexity is kept low and estimation is accurate,even adopting the simplest estimation method,Un-Weighted Linear Predictor (UWLP).Furthermore this frequency estimator has been realized by FPGA.The computer simulation result shows the proposed method has good performance.关键词：frequency estimation;iterative algorithm;filter banks2|1064|1更新时间：2025-07-16
- 摘要：Wireless sensor network is featured by small node size and memory,low computing capability,battery supplied energy,high node density and huge network scale.In view of the above features of wireless sensor network,an effective broadcast protocol (EBP) is presented in this paper.In the discussion on the induced rebroadcast of a node’s rebroadcast,the optimized induced rebroadcast are analyzed.In EBP,optimized rebroadcast nodes are selected based on the above analysis results and each node need not any neighbor information to complete a broadcast efficiently.Thus,the control and memory overheads are reduced greatly.The simple and effective EBP algorithm performs well in wireless sensor network.关键词：wireless;sensor network;broadcast;rebroadcast2|1226|5更新时间：2025-07-16
- 摘要：Aiming at the characteristics and requirements of the space-based optical surveillance,the methods of the Two-Line Elements(TLE) conversion were modified for the bearing-only passive tracking.Based on the trajectory sampling fitting method of the TLE,the nonlinear least square estimation method using bearing-only measurements was brought forward.The single point fitting of the TLE and the SGP4 propagator was embedded in the procedure of the tracking filter,and sigma points kalman filters was adopted in hybrid coordinates to enhance the stability of the tracking filter.Simulation results indicate that the space object passive tracking with perturbations can be realized using space-based optical measurements,and at the same time the TLE of the non-cooperative space object can be obtained.关键词：two-line elements;space object;space-based optical surveillance;tracking2|1160|1更新时间：2025-07-16
- 摘要：The reversal development of input verse output non-linear signals is presented by using a so called "Ten-Normalized Algorithm".The key point is that the maximum and minimum output signals are taken respectively as ten and zero on the ordinate axes.Other output signals are located in the range of them according to their ratios.The input signals can be expressed as a polynomial of the reversal development for output signals with five orders,which is an interlaced series with five orders.The approximate coefficients of the first and second order can be obtained from two sampling values by solving their two coupled equations.The other three coefficients of the high orders can be obtained by introducing them into the polynomial of reversal development until each computed values are respectively close to their sampling values after a lot of iterations from their possible minimum to maximum coefficients of the high orders,step by step.The possible range is estimated by using a normalized matching polynomial,according to all of situations for the probable experimental data distribution to minimize the range for searching the optimum coefficients.At last,a polynomial with five orders of the reversal development for output signals verse input signals is obtained,after the "ten-denormalized"process.An example was taken from the reversal development of input verse output signals for an ethanol sensing device.The input signals were ethanol equi-quantities;the output signals were the resistance of the sensing element or the voltages over it.After processing the output signals through a microprocessor,the ethanol quantities were revealed as results from the reversal development.The precision of the reversal development was±1.5% of ethanol quantities.关键词：reversal development of input verse output signals;ten-normalized algorithm;estimating the ratio among coefficients of polynomial;ethanol sensing devices2|779|2更新时间：2025-07-16
- 摘要：It is derived from elastic theory that the expressions of shifts of the energy levels in semiconductor quantum dots.The strains of the semiconductor quantum dots are calculated by finite element method.By combing the two results,the variation of all energy levels in strain quantum dot are educed.It is pointed that the conductor band will be decreased (or risen).The shift of the decreased (or risen) is decided by material of the quantum.The heavy hole band and the light hole band are split-off in stain quantum dot.The shifts are decided by the material and the shape of the quantum dot.关键词：quantum dot;residual strain;energy level shifts;finite element method2|781|0更新时间：2025-07-16
- 摘要：Aiming at the existed following error and control precision problem of numerical PID control system in high speed synchronous servo control system,a set of adaptive inverse control strategy was put forward.Using host motor as reference model and LMS adaptive control algorithms adjusting controller,the proposed method made supply motor have approximate dynamical property with host motor.The simulation results and product detecting results demonstrate that the proposed system can effectively reduce the following error and increase the precision of control system.关键词：adaptive inverse control;servo motor;LMS algorithms;numerical control multi-wire saw2|1310|1更新时间：2025-07-16
- 摘要：Relationship between tautologies in fuzzy modal logic and valid formulas in basic modal logic is investigated.It is proved that modal tautologies are logically valid but not vice versa;Based on a class of continuous binary relations,the concept of quasi-tautology is introduced in fuzzy modal logic,basic properties of quasi-tautologies is obtained,and a class of tautologies and quasi-tautologies are constructed by means of theorems in the logic system ￡*.关键词：fuzzy modal logic;basic modal logic;tautology;valid formula;quasi-tautology;modal logic system M￡*2|866|6更新时间：2025-07-16
- 摘要：An approach based on kernel SMOTE (Synthetic Minority Over-sampling Technique) to solve classification on imbalance data set by Support Vector Machine (SVM) is presented.The method first oversamples the minority class in feature space by kernel SMOTE algorithm,then the pre-images of the synthetic instances are found based on a distance relation between feature space and input space.Finally,these pre-images are appended to the original data set to train a SVM.Experiments on real data sets indicate that compared with SMOTE approach,the samples constructed by the kernel SMOTE algorithm have the higher quality.As a result,the effectiveness of classification by SVM on imbalance data set is improved.关键词：imbalance data set;support vector machine;input space;feature space;pre-image2|3008|26更新时间：2025-07-16
- 摘要：In Traditional binary or multiple classification problem of machine learning,each class of samples is necessary for classifier design;however,in some case only one class of samples can be acquired (due to the complexity or the expensive costs),so we have to learn from the only one class of samples and form the data description for classification.The classification problem is named as one-class classification.Since now there exist the domain-specific and the generic methods,this paper first presents an overview on one-class classification,then emphasizes on the analysis of the kernel-based one-class classifiers and divides this class of methods into two types,that is,dual-based and kernel-induced distance based.Hereafter,the characteristics of these two types of methods are analyzed.Finally,we summarize the implementation techniques and applications of one-class classification in fault analysis,anomaly detection,and disease diagnosis and hostility recognition.关键词：one/single-class;kernel methods;classifier;anomaly detection2|2254|27更新时间：2025-07-16
- 摘要：The sandwich ultrasonic transducer with two sets of piezoelectric ceramic elements is studied.When the active piezoelectric ceramic elements are excited separately,two resonance frequencies can be obtained.Based on the Mason electro-mechanical equivalent circuit,the resonance frequency equations are derived.The dependency of the resonance frequency on the geometrical dimensions and the electric boundary conditions is analyzed.It is shown that the resonance frequency of the transducer at electric short circuit is low than that at electric open circuit.At both electric boundary conditions,the resonance frequency is decreased when the radial dimension is increased.关键词：sandwich transducer with two sets of piezoelectric elements;electro-mechanical equivalent circuit;resonance frequency2|2452|4更新时间：2025-07-16
- 摘要：A non-aliasing Pyramidal transform,namely NAP transform,is presented to avoid the frequency aliasing of Contourlet transform.NAP transform consists of non-aliasing pyramidal filter banks (NPFB) and DFB.In this paper,we firstly represent the definition and specific parameter setting of NPFB in the frequency domain.NPFB decomposes image into an approximation subband and several detail subbands with different resolutions;whilst DFB decomposes the detail subbands into directional subbands.Not only has the basis function of NAP transform a variety of characteristics such as multi-resolution,multi-direction,localization to meet demands of anisotropy scale relations,but also are their regularity and localization better than those of Contourlet transform in the spatial domain.Results from the experiments of image denoising show that NAP transform can represent image more sparsely and has a significant improvement from the aspect of image denoising,compared with Contourlet transform.关键词：contourlet transform;non-aliasing pyramidal filter banks;basis function;image denoising2|743|2更新时间：2025-07-16
- 摘要：In the thermal design of stacked three-dimensional multi-chip module (3D-MCM),the placement of multiple chips on 3D-MCM substrate has a significant effect on temperature field in the 3D-MCM,thus influences the reliability of the 3D-MCM.The thermal placement optimization of chips in stacked 3D-MCM was studied in this paper,the goal of this work is to decrease temperature and achieve uniform thermal field distribution within stacked 3D-MCM.The average temperature of chips in stacked 3D-MCM was chosen as the evaluation target based on thermal superposition model and equation of heat conduction,and the fitness function for thermal placement optimization was determined.Based on genetic algorithms,chips placement optimization algorithm of thermal model was proposed and the optimization chips placement of stacked 3D-MCM was achieved by corresponding optimization program.Based on this work,the chips placement rules which can be used for directing thermal design of stacked 3D-MCM were summarized.To demonstrate the effectiveness of the obtained optimization chips placement,by using ANSYS,finite element analysis (FEA) was carried out to assess the thermal field distribution of the optimization chips placement in stacked 3D-MCM,the result shows that the thermal field distributions of the optimization chips placement are in good accord with the FEA results.It turns out that the chip placement optimization approach proposed in this work can be effective and robust in providing thermal optimal design of chip placement in stacked 3D-MCM.关键词：stacked 3D-MCM;genetic algorithms;thermal placement optimization;thermal superposition model;finite element analysis2|775|3更新时间：2025-07-16
- 摘要：The structure of SiGeC p-i-n power diodes with ultra-low leakage current and ultra-fast recovery characteristics is presented.Based on the current transport mechanism of heterojunction,SiGeC diodes achieve a low on-state voltage drop under high current density and improved reverse recovery characteristics as well as low reverse leakage current.Compared to lifetime control technology of minority carrier,the contradictions among decreasing on-state voltage,reducing reverse leakage current and shorting reverse recovery time are coordinated effectively.The reverse recovery characteristics under different temperature show that the reverse recovery times of SiGeC diodes are shortened by 1/3 at 350K and shortened by more than 40% at 400K,compared to SiGe diodes with the same structure.The thermal stability of the devices is improved significantly,which reduces the restrictions on subsequent process and is of benefit to power integration.关键词：SiGeC;ultra-low leakage current and ultra-fast recovery characteristics;thermal stability3|779|1更新时间：2025-07-16
- 摘要：A convolutive blind source separation algorithm based on tri-quadratic joint block diagonalization is proposed by utilizing the mutual-independence and quasistationarity properties of speech signals.The three subgroups of the undetermined parameters are iteratively estimated through minimizing the corresponding quadratic cost subfunctions alternatively.Analyses prove that the proposed algorithm has low computational complexity and robust convergence.Compared with the classical Jacobi-like methods,simulation results show that the proposed algorithm can improve both the global rejection level about 5dB and the Bark spectral distortion factor about 0.12 in average with faster convergence rate.关键词：joint block diagonalization;convolutive blind source separation;tri-quadratic minimization;Jacobi-like algorithm2|1006|0更新时间：2025-07-16
- 摘要：To overcome the poor adaptive ability of the fixed-rate Low-Density Parity-Check (LDPC) codes when applied to video compression,a kind of distributed video compression scheme based on rateless LDPC is proposed.The main idea of the algorithm is that part of variable node is punctured to adjust the puncturing ratio for rate adaptive ability.A novel rate estimation method is also proposed in encoder,it can solve the problem of needing the feedback channel for rate control in distributed video coding currently,and supply the rateless LDPC to design multiple code mode.Experiments results show that proposed scheme access the 1-2dB gain of rate distortion (RD) compared with rate-adaptive LDPC Accumulate (LDPCA) codes.The decoder complexity magnitude of proposed scheme is 2 orders less than the motion-oracle algorithm.关键词：rateless low-density parity-check;rate control;wyner-ziv code;punctured code2|1053|1更新时间：2025-07-16
- 摘要：Motion estimation (ME) is vital to video compression.Due to the adoption of the high precision of motion vector (MV) in H.264 encoder,the computational cost increases rapidly,and ME takes almost 80% encoding time.In this paper,based on the UMHexagonS algorithm,an optimized algorithm is proposed based on the dynamic search range selection,big hexagon and small hexagon search mode respectively,which saves ME time effectively without quality loss.Experimenting with some typical video sequences proves that,compared to UMHexagonS algorithm,our optimized algorithm can save about 18.292% ME time and reduce the complexity of original scheme as well as enhance the real-time performance of the encoder but almost has no change in the reconstructed picture quality and bitrate.关键词：motion estimation;dynamic search range;UMHexagonS;H.2642|1724|6更新时间：2025-07-16
- 摘要：The feature of magnetron exciting process can be used in the Specific Emitter Identification of self-oscillatory emitters.In this paper,a Particle In Cell (PIC) simulation was taken to verify a magnetron’s empirical circuit model and the features derived.At the beginning,the Slater circuit model was given,based on which the transient and steady solutions of the free and controlled oscillations were derived.Then the pushing coefficient feature,self-excitation exponent feature and the steady solution feature were presented.After that,a magnetron PIC simulation model was set up.Using the model,a free oscillation process was simulated to verify the pushing and exponent features.A controlled oscillation process was simulated to verify the pushing and steady solution features.The analysis results prove the effectiveness of the features.关键词：electrical war;emitter identification;specific emitter identification;emitter fingerprinting;self-oscillation;magnetron2|690|1更新时间：2025-07-16
- 摘要：Task allocation problem is one of the import researches of multi-agent system.For the complex problem,many researchers from different points of view put forward a variety of effective algorithms.These algorithms are effective for the determinative environment,but for the uncertain and dynamic environment are deficient.In this paper,fuzzy characteristics of dynamic task environment are researched,using dynamic fuzzy set theory,given the relevant multi-Agent dynamic task allocation algorithm.Examples of the test show that the algorithm model can be a reasonable simulation of MAS system operation task allocation process,and have achieved the optimal task allocation strategy and a good effect.关键词：multi-agent;task allocation;Dynamic Fuzzy Set(DFS);reinforcement mechanism;genetic algorithm3|921|4更新时间：2025-07-16
- 摘要：In the P2P network,nodes can join in or leave freely,and they are highly autonomic.Therefore,the dangerous from the network inside should be noticed.In this paper a decentralized authentication mode,which is based on eclipse curve cryptosystem and threshold secret sharing scheme,is proposed.This system replaces the Certificate Authority (CA) central server and has many advantages such as low cost,high adaptation,high availability,and intrusion-tolerance.At the same time,verified secret sharing is used to protect the secret key of CA.关键词：P2P net work;elliptic curve cryptography;distributed signature;threshold cryptography4|793|3更新时间：2025-07-16
- 摘要：A RFID technology and anti-counterfeiting system was studied in this paper.Firstly,we propose a hardware and software framework of anti-counterfeit system based on RFID technologies; furthermore the hierarchical structure of the anti-counterfeit system was analyzed in details.Then aimed at the complexity of the anti-counterfeit system an intelligent attacking model was presented here,and the A* algorithm is adopted in this attack model and used to search a lowest price tree by the fictional attacker in order to evaluate the proposed anti-counterfeit system especially for the protocol used in this system.Finally,an experimental testing with VC+ + and Matlab was simulated.Simulation results indicate that the proposed modeling methods can be used effectively to model complex anti-counterfeiting systems.关键词：model;protocol;radio frequency identification (RFID);cost-tree2|1385|4更新时间：2025-07-16
- 摘要：We present a GPU-based algorithm for solving linear programming problems using simplex methods under CTM (close to the metal) environment.Matrix-packed storage strategy and correlative computation formulas such as revised basic matrix、simplex multiplier and departing variables are brought forward,according to the fact that at most one column vector produces in each vertex changing step and the feature of reverse matrix of simplex method.CPU takes charge of the iteration and all compute-intensive tasks are carried out by GPU.Theory analysis proves that both space complexity and time complexity are superior to traditional method.Numerical experiments on randomly generated problems demonstrate that this method can not only get correct optimal solution,but also reach as fast as hundred times of CPU-based version;and it runs several times faster than MATLAB R2007a.关键词：simplex method;graphics processing unit;close to the metal;texture;pixel shader2|1337|0更新时间：2025-07-16
- 摘要：The way of triangulating spatial points based on manifold study is advanced in this paper. According to the theory of manifold,spatial points is the measurement result of a certain 2D manifold in 3D space,so the process of triangulation is to search 2D manifold substantively.Therefore,the paper divides triangulating spatial points into three steps.The first step is to decrease the dimension of points on basis of the correlative relation among points within a certain distance and the condition of minimizing the reconstruction error.The second step is to carry out Delaunay partition for points on plane.At last,the topology connection relation is mapped to 3D spatial points.The result is that the difference between the triangle net and object’s surface achieves minimum practicality.This way can be easily acknowIedged,reduces complication and diminish the diversity in triangulation.Many experiments show the method provided in paper can achieve good result for objects which are not homeomorphism to sphere by choosing appropriate method of manifold study and neighborhoods.关键词：manifold study;Triangulation;Topology;mesh3|1934|1更新时间：2025-07-16
- 摘要：Aim at the defect that weighted k-nearest neighbor method classifies one test sample only using the class information of its k-nearest samples,a sequential weighted k-nearest neighbor classification method is proposed in this paper.Not only the class information offered by k-nearest neighbor points of test sample but also the class information of previous test sample is used for classification in the proposed method.So its decision-making processing is more reasonable and effective.The experimental results of facial expression recognition in Cohn-Kanade face database show the method is better than weighted k-nearest neighbor method for the classification of sequential samples.关键词：weighted k-nearest neighbor;manifold;Bayesian rule;sequential weighted k-nearest neighbor2|1224|12更新时间：2025-07-16
- 摘要：For successful application of COTS (Commercial off-the-shelf) components in high reliable space systems,the history of COTS used in space systems was inducted and the general route was investigated.Traits of the route were COTS’reliability screening and COTS’reliability evaluation test ahead of the screening,and the relationship between reliability technologies and mission profile.A formulate of burn-in temperature and time adapted to different reliability requirements was researched according to NASA’s rules.Regression models adapted to different missions were investigated and verified.Cases indicated that the method of thermal reliability evaluation test is useful in engineering and the total-ionizing-dose reliability screening model’s relative error is 1%.The systemic method of COTS applied in space items is significant and certificated by engineering practices.关键词：commercial off-the-shelf components;space application;reliability evaluation test;reliability screening2|3922|13更新时间：2025-07-16
- 摘要：When distributed data is classified by traditional and single BP algorithm,training speed is low and the local optimum is immersed readily.To solve the problem,in the present research,it presents hybrid classification algorithm based upon GEP-BP (HCA-GB).In the HCA-GB,range of GEP population is adjusted dynamically by means of self-adaptive coefficient.On the basis of HCA-GB,this paper proposes classification of distributed GEP-BP on grid service (CDGB-GS),which combines grid service and HCA-GB to resolve classification of distributed data.By simulated experiment,it is showed that the average number of convergence of HCA-GB is improved about two times by means of adjusting self-adaptive coefficient.For very large and complex data sets,average consumptive time of CDGB-GS is less than traditional algorithms,and classification accuracy of CDGB-GS is improved by about 32.06% at most in proportion with traditional algorithms.关键词：distributed algorithm;gene expression programming;grid service;classification2|847|2更新时间：2025-07-16
- 摘要：A fusion method with self-adjusting weights is proposed,which measures the classifier performance by the confusion matrix,and self-adaptively assigns weights to classifiers based on their outputs.Bigger weights are assigned to reliable outputs so that the decision templates are more credible.For a sample which is prone to be misclassified,besides the similarity between it and the decision templates,the information of the training samples around it are included to make a decision.Experiments were done on the KDD’99 intrusion detection dataset and 8 datasets from the database UCI to compare the proposed method with the DT method.The experimental results show the presented method has a better classification performance.关键词：multiple classifier systems;decision fusion;confusion matrix;decision template2|1511|8更新时间：2025-07-16
- 摘要：Network traffic prediction is very important in network protocol designing,network management and high performance routers designing etc.Currently,ARMA and FARIMA time series are the main models used to fit and predict the network traffic.But the relation between time scale and time series models hasn’t been studied.The network traffic was modeled according to different time scales using the traffic trace data taken from the Internet traffic archive,and the prediction performance of those models was compared.The results show that time series models perform better under the large scale(minute)than under small time scales(millisecond and second),and the performance of self similarity model FARIMA shows no advantage over other models.关键词：traffic prediction;time series models;time scale2|3516|54更新时间：2025-07-16
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