最新刊期
卷 35 ， 期 11 ， 2007
- 摘要：Genetic algorithm is used in BSIMSOI4 model parameter extraction for sub-100nm SOI MOSFETs to simplify extraction process and optimize parameters globally.An extraction algorithm called adaptive genetic algorithm maintaining multi-optimum is proposed.In the new algorithm,multiple copies of the optimum chromosome in each generation are kept,induced and dynamic mutations are carried out on chromosomes with larger and smaller fitness,respectively,and random and induced crossovers are executed in the early and late generations,respectively.The global optimization is maintained,the local searching is speeded up and the quality of the final solution is improved.Extraction examples under different population sizes and evolutionary steps show that the new algorithm has the advantages of higher accuracy,faster convergence,and reliable global optimization and that global convergence could be speeded up by increasing population sizes properly.关键词：SOI;parameter extraction;global optimization;model2|1336|2更新时间：2025-07-16
- 摘要：Wireless sensor networks (WSNs) always consist of many mobile and stationary sensor nodes.Dynamic sensor deployment is one of the key topics addressed in the research of WSNs,which is adopted to improve the coverage and detection probability of WSNs.The performance of virtual force (VF) algorithm may be deteriorated because the stationary sensor nodes will confine the global optimal searching ability.This paper proposes a dynamic sensor deployment strategy for WSNs,so-called virtual force-directed particle swarm optimization (VFPSO).VFPSO combines the VF with particle swarm optimization (PSO),where the velocity of each particle is updated according to not only the historical local optimal solutions and global optimal solutions but also the virtual forces of sensor nodes.The key motivation of this strategy is to use the virtual force to direct the updating of PSO for improving the convergence speed,and PSO is used to enhance the global searching ability.Simulation results demonstrate that VFPSO has better performance on regional convergence and global searching than VF algorithm and PSO algorithm,and it can implement dynamic sensor deployment efficiently and rapidly.关键词：wireless sensor networks;dynamic sensor deployment;particle swarm optimization;virtual force2|2189|36更新时间：2025-07-16
- 摘要：With technology scaling into nanometer regime,VLSI chips become much more complex and suffer from rampant process variations.Therefore,statistical methods are replacing deterministic counterparts for power/ground(P/G) grid analysis and efficient local analysis methods are badly needed to reduce the analysis complexity.A novel single-node Successive Over Relaxation (SN-SOR) method is proposed to efficiently solve correlated resistor vectors and then to directly compute voltage variations for question nodes of large IR droop.Compared with traditional global SOR methods,the SN-SOR method shows following advantages.First one is locality.Because only one stimuli is located at the question node q to compute the correlated resistor vector Rq,SN-SOR relaxes nodes from q to its surround nodes as wave transmission and the wave stops at some nodes whose IR droop is less than one assigned little value.Second one is efficiency.SN-SOR only relaxes small parts of nodes in P/G circuits but also needs slightly less relaxation reiterations.Third one is low memory complexity.Among Rq,SN-SOR only needs some strong correlated resistors and less weak resistors of typical nodes to compute the voltage variation.Experiments show SN-SOR is 20 times faster than global SOR methods with only 0.38% accuracy loss.关键词：VLSI;P/G network;statistic analysis;SOR;single-node analysis2|801|0更新时间：2025-07-16
- 摘要：We studied the effect of thin film thickness on the performance of double-layer heterojunction organic light-emitting diodes (OLEDs) based on 4,4'-bis biphenyl (NPB) as hole transporting layer and tris-(8-hydroxylquinoline)-aluminum (Alq3) as emitting layer.Various devices with different NPB and Alq3 thickness were fabricated and their electroluminescent characteristics were investiagted.The results show that the device current dosen’t change with Alq3 or NPB film thickness in the same trend.The current mechanism of devices with different organic film thicknesses conforms with the theory of trapped charge limited current(TCLC).Current varies from ohmic conduction region,TCL region to trapped charge limited-space charge limited (TCLC-SCLC) transition region with the increase of applied voltage.High device performance could be obtained when thin film thickness is NPB(20 nm)/Alq3(50 nm).The luminance efficiency-voltage curves of devices reached to the maximum under low-voltage,and gradually decreased with rising voltage.关键词：organic electroluminescence;NPB;Alq3;film thickness;trapped charge limited(TCL);device performance2|1222|2更新时间：2025-07-16
- 摘要：Inspired by the theory of two visual pathways,a novel model for object detection is proposed based on "what" and "where" information.Context-centered "where" information is used to control top-down attention,and guide bottom-up attention which is driven by "what" information.The procedure of top-down attention can be divided into two stages:pre-attention and focus attention.In the stage of pre-attention,"where" information can be used to provide the prior knowledge of presence or absence of objects which decides whether search operation is followed.By integrating the result of focus attention with "what" information,attention is directed to the region that is most likely to contain the object and series of salient regions for samples are detected.Experimental results with natural images demonstrate its effectiveness.关键词：top-down attention;"where" information;"what" information;object detection2|943|1更新时间：2025-07-16
- 摘要：A new combined field integral equation is proposed to analyze the electromagnetic scattering for composite conducting and dielectric object.Through properly choosing the coupling coefficients of the equations,the resultant matrix equation achieves better convergence properties.The restarted generalized minimum residual method (GMRES) is applied in the multilevel fast multipole algorithm (MLFMA) and preconditioning technique is used to further improve the convergence rate.Numerical examples are presented to compare the efficiency of different methods and show the validity and high efficiency of proposed method.关键词：electromagnetic scattering;composite conducting and dielectric object;multilevel fast multipole algorithm(MLFMA);combined field integral equation(CFIE);preconditioning technique2|1517|5更新时间：2025-07-16
- 摘要：Based on the concept of random contention and collision resolution,a distributed quality-of-service-guaranteed multiple access (QMA) protocol for ad hoc networks is proposed to support multimedia service and multi-hop architecture.In the protocol,nodes broadcast forecast bursts (FBs) to access channel resources before their packets transmissions based on their recent packet delay and the earliest deadline first (EDF) principle,and the one that broadcasts the most FBs gets right to use the channel.Meanwhile,the nodes with real-time traffic can access channel prior to those with non real-time traffic by broadcasting FBs from earlier FB mini-slots,while the nodes with non real-time traffic are allowed to start to broadcast FBs on condition that all the former FB mini-slots for real-time traffic are idle.Therefore,the proposed protocol can provide QoS guarantees for multimedia traffic in mobile ad hoc networks.Finally,by the means of simulations in OPNET modeler,it is shown that the QMA protocol outperforms the IEEE 802.11e protocol in terms of throughput and average packet delay,especially for real-time traffic.关键词：mobile ad hoc network;multiple access protocol;quality-of-service (QoS);distributed reservation;collision resolution2|1177|2更新时间：2025-07-16
- 摘要：In the integrated circuits with frequency above several GHz,parasitic inductive effect has extremely influenced the circuit performance.Therefore,efficient algorithms are required to extract the frequency-dependent parameters which capture the inductive effect.The recently proposed K element (inverse of the partial inductance) has a good localization property,and has been widely accepted for the modeling of parasitic inductance.However,most previous works on reluctance extraction did not take high frequency effect into account and were not efficient enough for 3-D complex structure In this paper,a set of algorithms are proposed to extract the frequency-dependent K element and resistance of 3D interconnects.With a windowing technique,a direct K extraction algorithm,and improvements on solving equations within the window,the proposed method is able to handle complex interconnect structures very efficiently.Compared with FastHenry,the presented method has a speedup ratio from several tens to several hundreds,while preserving good accuracy.关键词：inductance extraction;K element;high frequency;VLSI2|1035|0更新时间：2025-07-16
- 摘要：A moment gait energy image (MGEI) based gait recognition algorithm is presented.Gait period is estimated from swing distances,and key moments of a gait cycle are specified.The mean of all the silhouette images at a key moment is called the mean moment image.The MGEI at each key moment is calculated from all the mean moment images in gait period.It improves silhouette's quality by gait probability distribution at each key moment,and provides more motion features than the basic gait energy image (GEI).Then a method of gait feature extraction is proposed based on MGEI.The deviations of silhouette images from MGEI at every key moment are cumulated into an image,which is utilized together with GEI to represent a subject.The nearest neighbor classifier is adopted to recognize subjects.The proposed algorithm is evaluated on USF dataset,and the performance is compared with the baseline algorithm and two other new algorithms.Experimental result shows that this algorithm achieves higher overall recognition rate then the other algorithms.关键词：biometrics;gait expression;gait recognition;feature extraction;gait period6|1428|10更新时间：2025-07-16
- 摘要：Different from JEDEC standard test board,a round test board was introduced to do drop test and simulation.Lead-free solder joint reliability under board-level drop impact was investigated.Firstly,modal test was conducted in order to understand dynamic properties of test board.Secondly,strains and acceleration of test board were measured during drop test,and ABAQUS software was used to do drop simulation and model stresses and strains of solder joints under drop impact.Results show that the model established has close values of acceleration response and strain histories as measured in actual drop test,and the failure mode and critical solder ball location predicted by modeling correlate well with testing.The fracture occurs in intermetallic composite (IMC) on the package side.Failure mode is brittle fracture.关键词：lead-free solder joint;board-level drop;finite element;intermetallic composite;failure2|2284|3更新时间：2025-07-16
- 摘要：Facial Action Units (FAU) tracking is a hard problem for the rigid and non-rigid transformations of human face.The constantly trembling in the tracking result and the tracking failures caused by the absence of constraint remain open problems.This paper presents a novel method to attack these problems by combining Gaussian Process and Particle Filtering.Gradient-based method and particle filtering based method are compared with our method and the experiment results are encouraging.关键词：FAU tracking;gradient optimization;particle filtering;gaussian process2|1167|5更新时间：2025-07-16
- 摘要：The nature of the increasing network traffic has taken much more changes.In order to find out how these changes impact on the traffic character,we make a comprehensive analysis by using the traffic data collected with NetTurbo on an ISP WAN link.The result shows that compared to the previous analysis there are so many un-neglectable differences in the traffic characterization.More significantly,we found that despite its wide use,there is still much confusion regarding the identification of self similarity in recent real network traffic data and whether the self similarity still exists is uncertain,which is much more difference from the previous result.关键词：WAN;traffic measurement;traffic character;self similarity;hurst parameter2|1470|7更新时间：2025-07-16
- 摘要：To cover the shortages of the existing FIFO architecture,a new FIFO architecture,WG-FIFO,is presented in this paper.The WG-FIFO encodes write/read pointer with a weighted-gray code,and controls write/read operation with a real-time global states detector.Simulation results show that the performance,area cost,and write/read operation efficiency are all considerably improved compared with other available FIFO architectures under the depth range of 4~16.For example,when the FIFO depth is 8 and the data width is 32,compared with B-FIFO,the highest clock frequency is increased by 31.6%,cell area cost is decreased 17.1%,and write/read efficiency is improved 47% at most.关键词：First-In First-Out (FIFO);high performance;Gray code;asynchronous;synchronizer2|2157|2更新时间：2025-07-16
- 摘要：This paper addresses the problem of the stability of congestion control for networks with large round-trip communication delays.Nearly all the existing AQM schemes neglect the impact on system behavior,such as stability,robustness and convergence,caused by large communication delay.The drastic queue oscillations in large delay networks of PI,REM and DC-AQM decrease the link utilization and introduce the avoidable delay jitter.To address this problem,we develop a robust IMC-PID congestion controller based on internal model control principle to restrict the negative impact on the stability caused by the large delay.Simulation results demonstrate that the integrated performance of proposed scheme outperforms others as communication delay increases,and achieves high link utilization and small delay jitter.关键词：congestion control;active queue management;internal model control;large-delay networks;stability2|1360|2更新时间：2025-07-16
- 摘要：Binary entity relationship tuples can be applied in many fields such as knowledge base construction,data mining and pattern extraction and so on.A seed with a tuple and a keyword of a special relation is used to implement the method of extracting entity relation tuples from the web.Multiple Natural Language Processing (NLP) technologies are combined in this method.A novel pattern acquisition method and an improved bootstrapping iteration strategy are adopted to extract tuples.The baseline method achieves to 78.12% of average precision.The method with filtering measure achieves to 98.42%.The experimental results show that it can satisfy information extraction application well and the extracted tuples can derive more valuable information through further processing.关键词：bootstrapping;entity relation;tuples;information extraction;web mining2|1326|5更新时间：2025-07-16
- 摘要：Signcryption provides confidentiality and authenticity efficiently;it can be used to design compact communication protocol.Arbitration mechanism is used for settling disputes in signcryption,but the information that the judge gets also brings some security problems.This paper points out two problems:in some scheme,the arbitrator can decrypt all the signcryptions of a receiver while he gets some kinds of arbitration message;in another schemes,the arbitration mechanism cannot protect the integrity of plaintext.Analyze the two kinds of problems and concludes their reasons separately,we proposed a resolvent that can solve the two problem by changing a secure arbitration message.Based on the attack and analysis,this paper proposes a secure arbitral signcryption (SASC) scheme and proves its IND-CCA2 security and UF-CMA security in random oracle model.Furthermore,SASC is a securely arbitral signcryption scheme,it can protect the integrity of plaintexts by an arbitration message associated with plaintext;and the scheme can resist decryption attacks of arbitrator,even he gets the arbitration message.SASC does not increase computation nor communication overloads;it has no limitation to the length of plaintext,which makes SASC more convenient.Proofs and analysis show that SASC is an efficient and secure scheme.关键词：signcryption;security of arbitration;random Oracle;provable security2|955|0更新时间：2025-07-16
- 摘要：Due to the excellent performance and flexibility,reconfigurable computing has gained more and more attention throughout the world.But currently there’re so many different platforms and programming frameworks which take you into the details of the specific hardware,and prevent their practical usage.In this paper,after deep study of the reconfiguration characteristic,a novel data-driven uniform programming model RECUPM is proposed,and its implementation is discussed.The model supports parallel hybrid-task computing.It’s based on producer-consumer communication paradigm and can be adapted onto different types of networks and nodes.Experiments show that applications featuring RECUPM reuse the same source codes on different architectures,and outperform the pure hardware acceleration design.关键词：reconfigurable computing;programming model;producer-consumer communication model4|1283|4更新时间：2025-07-16
- 摘要：To keep up with the pace of fast development of Internet,cluster architecture has been proposed for next generation core routers.In a cluster router,parallel computation is expected.Computing shortest path tree (SPT) is a fundamental problem implementing OSPF,which is one of the most popular routing protocols.This paper presents a parallel algorithm D-D(Divisional-Dijkstra Algorithm)for computing SPT,analyzes the performance of D-D,and finally validates the D-D performance by experiments.关键词：cluster router;routing node;SPT;Divisional-Dijkstra(D-D);parallel algorithm2|1372|2更新时间：2025-07-16
- 摘要：Research on LDPC codes is in the ascendant nowadays.Our paper has done some work on the proposition of "performance of different codes in the same family constrained by weight distribution polynomials".Different codes of the same weight distribution are listed,and the results indicate the upper performance is determined by density evolution theory and the lower performance limit by the Fill-Shift construction method.Furthermore,the codes in the collection of elementary matrix transformation share the same error-correction performance but different coding complexity.We can get a conclusion that codes constrained by weight distribution polynomial can be divided into many groups,performance among different groups is not the same,it depends on the loops length and distribution,and performance in the same groups is identical.What we can do now is that to find the best group and do suitable transformations if given weight distribution polynomials.Through this paper,we can see that a new idea for code constructing is also presented.If the relations between big girth of LDPC codes and weight distribution polynomial are discovered,new codes can be achieved only by the weight distribution polynomial,the currently used method given in references for code constructing will be less useful.We can think that we have found a completely different method to construct LDPC codes.关键词：low density parity check(LDPC) codes;density evolution;code family;elementary transformation;weight distribution polynomial3|1029|0更新时间：2025-07-16
- 摘要：For the larger search space when learning clause in Inductive Logic Programming,we defined the clause template.Firstly,we learn the clause templates by Genetic Algorithm,and then convert it to the requisite clauses by combining tag matrix and information gain sampling.We designed the corresponding fitness function and genetic operators.Theoretical analysis and experiment comparison show that this algorithm can reduce the search space,improve the search efficiency and can learn recursion clause.It is an effective clause learning algorithm.关键词：inductive logic programming;clause template;genetic algorithm;recursion clause;information gain2|1050|0更新时间：2025-07-16
- 摘要：The task of complex time series predicting is hard to be accomplished with only one single predicting model.In this paper,a complex time series is decomposed into a series of intrinsic mode functions and a residue signal.Then a RBF network is constructed for an intrinsic mode function or the residual signal.Finally output of every predicting model is integrated into one output with equal weighted.As the sifting process of EMD is an approximate frequency dividing process,the relationship between the logarithm of optimal parameter of every RBF network and its corresponding Intrinsic Mode Function is also approximate linear.This relationship can be utilized to alleviate the computing burden of the model selecting with cross validation method.Experimental results showed that the proposed method outperformed the single RBF network in the task of predicting complex time series.关键词：empirical mode decomposition;radial-basis function network;cross validation method;time series prediction5|1395|3更新时间：2025-07-16
- 摘要：The article has studied the dynamic behavior of the chaotic PWM based on statistical tool and invariable distribution.The frequency characteristics of chaotic PWM have been analyzed based on the invariable distribution,characteristic parameters and spectrum characteristics are gained also.Simulation and experiment results show that the spectrum waveforms of drive pulse,switch voltage and inductance current have the same shape as the invariable distribution,so invariable distribution becomes a new effective method to abstract entail characteristics of chaotic converters,people can optimize the spectrum distribution of converter based on invariable distribution and get the best EMI suppressing effect.关键词：switch converter;invariable distribution;chaotic spectrum;EMI2|1078|1更新时间：2025-07-16
- 摘要：Attribute reduction is not only one of important parts researched in rough set theory,but also widely applied to many fields such as machine learning,data mining and so on.The attribute reduction method based on conditional information entropy can also be used effectively in the algebra view.However,these are two main disadvantages:this method is sensitive to noise and in some cases the obtained attribute subset may contain some redundant attributes.Therefore,in this paper,after introducing a concept of approximate reduction based on conditional information entropy in decision tables,we present an approximate reduction algorithm based on conditional information entropy(ARABCIE).The algorithm can effectively improve sensitivity to noise and properly select those redundant attributes by applications.Finally,we discuss the robustness of ARABCIE algorithm by experimenting on benchmark using several attribute subsets with different precision.关键词：rough set;attributes reduction;conditional information entropy;approximate reduction4|1621|36更新时间：2025-07-16
- 摘要：This paper presents a novel and effective classification method for imbalanced data sets.The core idea of the algorithm,which is composed of three parts,is to provide a general solution for IDS classification by both sample preprocessing and classifier improving.Firstly,we re-sample the imbalance data by using variable SOM clustering so as to overcome the flaws of the traditional re-sampling methods,such as serious randomness,subjective interference and information loss.Then we cut down the sampled data sets according to the K-NN rule to solve the problem of data confusion,which improves the generalization of SVM.Especially,in order to adapt the class imbalance,the class boundary alignment is introduced through conformal transform on kernel function.The comparison results show the effectiveness of three algorithms.Meanwhile,the algorithm has also been used in our question answer system,which obtains outstanding result in the international TREC-2006 QA track.关键词：imbalanced data sets(IDS);classification;support vector machine(SVM);variable self-organizing Maps(V-SOM);K-nearest neighbor(K-NN)2|1382|11更新时间：2025-07-16
- 摘要：An adaptive Sensor Resetting Localization (ASRL) algorithm based on traditional Particle Filter is proposed for mobile robot.The belief of robot is represented by a set of weighted samples,new necessary samples are calculated according to effective samples and resampled based on sensor data,and then old samples are replaced with new samples during ASRL algorithm.This algorithm is used on autonomous mobile robot AMR-ITL equipped with encoder and color camera sensor successfully,experiment result shows that ASRL is a more robust and quickly convergence algorithm.关键词：mobile robot;localization;particle filter;adaptive sensor resetting localization2|1406|5更新时间：2025-07-16
- 摘要：In this paper,we propose a bidirectional fuzzy flow framework based on fuzzy sets,which performs a fuzzy backward (inverse) diffusion along the gradient direction to the isophote lines (edges),while a certain forward diffusion along the tangent direction on the contrary.To preserve the natural transition of image features,the eigenvalues of local image structure tensor are used to detect different features,which are sharpened correspondingly.关键词：image enhancement;edge sharpening;direction-selective diffusion;fuzzy sets;structure tensor2|1241|2更新时间：2025-07-16
- 摘要：High flow rate of software talents is a key problem harassing the development of software enterprises.Comparing with traditional industries,the life cycle of software technology is shorter.The technical characteristics will necessarily affect the flow of human resources in software industry.Therefore,software talents need to improve their own technical ability to suit the rapid technical progress and innovation and to realize a better personal income.This has become the main reason for the higher flow rate of software talents than that of traditional industries’ talents.关键词：technical life cycle;talent flow;software technology2|1038|0更新时间：2025-07-16
- 摘要：Based on robust design and Finite Element Method,the thermo-mechanical fatigue reliability of PBGA (Plastic Ball Grid Array) solder joint subject to an accelerated thermal cycling test condition is studied.Including PCB size,substrate thickness,chip coefficient of thermal expansion(CTE),and solder joint CTE et al.,8 different control factors are considered for a robust design towards enhancement of the thermal fatigue resistance of solder joint by using a L18(21×37) mixed-level orthogonal array.From the result,importance of these factors on the thermo-mechanical reliability of PBGA solder joint is ranked.The best parameter combinations is A1B2C3D1E2F1G3H1,which the substrate CTE,solder joint CTE,the thickness of substrate,die CTE are the most important.The optimal design,after further confirmative experiments,decreases the maximum equivalent strain by 66% and increases S/N by 22.4% compared to the original design.关键词：plastic ball grid array;thermo-mechanical fatigue reliability;robust design;finite element method2|1184|1更新时间：2025-07-16
- 摘要：Lattice digital filter chips are widely used in many signal processing applications.We propose a built-in self-test (BIST) scheme for VLSI pipelined lattice digital filter chips which needs no modification of the basic building cells and all the single stuck-at faults can be detected in reasonable time.All the test vectors can be generated by simple arithmetic operation.By reusing available arithmetic function units such as accumulators to generate test vectors and compact test responses,such scheme can be implemented at-speed with minimum hardware overhead and performance degradation.关键词：built-in self-test;design for testability;lattice digital filter;pseudo-exhaustive test2|910|0更新时间：2025-07-16
- 摘要：A transimpedance preamplifier with automatic gain control (AGC) for 155Mb/s optic-fiber communication was designed and realized in CSMC 0.6 μ m standard CMOS technology.For the extension of input dynamic range,uses automatic gain control technique to monitor the variation of input dc component which is proportional to the magnitude of input current.When input current is large,transimpedance gain decreases to avoid output distortion.After analyzing contributions to equivalent input noise current of several elements in the circuit,gives a method of noise performance optimization.The measured results show that the pre-amplifier has differential transimpedance of 91.7dB Ω (38.5k Ω ),-3dB bandwidth of 125MHz,optical overload of 0dBm and average equivalent input noise current density of 4.8pA.Its power consumption is 180mW under single 5V power supply and the die area is 0.7×0.4mm2.关键词：automatic gain control;preamplifier;transimpedance;noise performance optimization3|1331|4更新时间：2025-07-16
- 摘要：This paper presented a novel piecewise curvature-corrected technology,which can be accomplished in standard CMOS process technology without any extra masks for temperature compensation.Temperature coefficient is improved by ten Compared to the first order compensation.This novel curvature-correcting scheme can be used in almost any process technology yielding reliable temperature compensation.The additional circuitry required for this correction is compact and is easily implemented.In SMIC 0.18 μ M CMOS process,a precision piecewise curvature-corrected differential bandgap reference is designed.The simulation results show that differential reference is 1.9997V,total noise is 225nV,and PSRR is 98dB.Meantime,the precision piecewise curvature-corrected single-end bandgap reference implemented in CSMS 0.5 μ M process is embedded in a monolithic 100MHz PWM BUCK DC-DC converter as reference voltage.Experimental results show that reference voltage is 1.2501V,total noise is 670nV,PSRR is 66.7dB,and temperature coefficient is improved by six.Differential or single-end reference can be under 1V through changing parameters due to the current mode,which is adapted to low-voltage low-power portable devices.关键词：curvature-correcting;bandgap reference;low-noise;nonlinear compensation;trimming2|1696|2更新时间：2025-07-16
- 摘要：The dependence of magnetostatic wave (MSW) modes and its bandwidth on the external DC bias magnetic fields in the magneto-optic film was illustrated.Three kinds of magnetostatic modes,those of the magnetostatic backward volume wave (MSBVW),the magnetostatic forward volume wave (MSFVW) and the magnetostatic surface wave (MSSW),was taken into account together by studying the generation of the magnetostatic waves under arbitrarily tilted bias magnetic field,and then the diffraction performance of the MSW-based magneto-optic Bragg cells may easily be calculated.Our calculation shows that,(1) for the same magnitude of external bias magnetic fields,in the conventional magnetization directions there is the largest MSW bandwidth and the operating frequency of the MSBVW-based Bragg cell is higher than that of the MSFVW-based Bragg cell,(2) under an appropriately inclined bias magnetic field,all three magnetostatic modes can respectively be excited at higher and higher frequencies,and (3) the MSFVW bandwidth may move to higher frequencies by tilting the external bias magnetic field.关键词：magnetostatic wave;bias magnetic field;magneto-optic film;Bragg cell4|1226|1更新时间：2025-07-16
- 摘要：To solve the problem that the colors of printer are nonlinearity and nonuniformity in CIE color space,a new calibration method is presented.When a CIE value is to be output,samples whose characters are consistent with that of the CIE value are first selected from the improved calibration samples.Then the subset,which is constructed by those selected samples,is used to correct the given CIE value to CMY value by multiple polynomial regression method.Experiments show that the proposed method improves the calibration precision obviously.关键词：color management;printer calibration;color calibration;polynomial regression2|1172|6更新时间：2025-07-16
- 摘要：As a test language of special domain,ATLAS (Abbreviated Test Language for All Systems) is difficult to be implemented for its proper device allocation.This paper proposes a kind of static device allocation algorithm based on the privative heuristic duple-back-tracing searching.Furthermore,according to the character of practical ATE (Automatic Test Equipment),two practicable heuristic functions are provided to guide the process of device allocation.Finally some instances are shown to indicate the algorithm can implement the static device allocation with better efficiency.关键词：device allocation;heuristic function;duple-back-tracing searching algorithm;algorithm analysis;device allocation request2|1001|0更新时间：2025-07-16
- 摘要：To reduce the response time of a parameter sweep application on high-performance computational grids,the number of tasks allocated to each grid node is determined based on load balancing.Job load of each grid node is represented by the ratio of processor requirements to processor number,the grid load imbalance degree is represented by the mean square deviation of job loads,and the task allocations of a parameter sweep application are determined by reducing the grid load imbalance degree.When the task number of a parameter application is not adequate to implement the grid load balancing,a set of nodes with lower job loads are selected,and the parameter application will be distributed on these nodes according to load balancing.Experiments show the load balancing-based scheduling can effectively reduce the response time of parameter sweep applications.关键词：computational grid;parameter sweep application;job load;grid load balancing2|872|0更新时间：2025-07-16
- 摘要：Families of pseudorandom sequences with low correlation are useful in a wide range of applications,such as code-division multiple access(CDMA) communications and cryptology,and the families with desired correlation can be effectively constructed by using function families over finite fields.In this paper,22n-2 families of binary sequences with low correlation are constructed by using two families of Boolean functions over the finite field with 2n elements,where n≡2(mod 4).There are 2n+1 binary sequences of period 2n-1 within each family,and the maximum correlation is 2n/2+1+1.The proposed construction can provide more families for CDMA communications and cryptology.关键词：pseudorandom sequence;low correlation;Walsh spectrum;equivalent class2|852|2更新时间：2025-07-16
- 摘要：Traditional keyword-based search engine does not consider the additional information provided by the structure of XML documents,it returns imprecise results often;searching according to keywords and structure information of XML documents inputted is not suitable for common users.Semantic search for XML data based on tag—keywords overcomes the limitations above,but its efficiency needs to be improved.This paper analyzes semantic information provided by the structure of XML documents deeply.It puts forward a new index structure for XML data and semantic related decision function between two nodes.Based on this,it proposes a fast semantic search algorithm for XML data.The search algorithm reduces the times to decide semantic correlation greatly.The experimental results with real data sets illustrate the effectiveness of the proposed algorithm.关键词：XML document;semantic search;index structure;information retrieval3|1238|1更新时间：2025-07-16
- 摘要：Hidden Markov model is one of important approaches for text information extraction.In the first-order hidden Markov model,there is the hypothesis that the transition probability of state and the output probability of observation are only dependent on the current state of the model,which debases the precision of information extraction comparatively.The relationship between the probability and the model’s historical states is considered reasonably in the second-order hidden Markov model which has stronger performance of recognition for incorrect information.An algorithm of text information extraction based on the second-order hidden Markov model is proposed.The validity of the second-order hidden Markov model in information extraction is analyzed.Simulation Experiments show that the new algorithm has higher precision than the algorithm based on the first-order hidden Markov model.关键词：text information extraction;the first-order hidden Markov model;the second-order hidden Markov model;precision2|2625|14更新时间：2025-07-16
- 摘要：Ad hoc networks posses dynamic topologies and self-organized nodes,which stunts the implement of distributed mutual exclusion algorithms.Aiming at the comparatively laggard level of the distributed mutual exclusion algorithms for Ad hoc networks,an adaptive algorithm for Ad hoc networks was presented as ADLE algorithm.Based on broadcast communication,the novel algorithm guaranteed the time sequence and prevents nodes from starvation by the logical timestamps.Furthermore,it decreased the message complexity and the delay complexity through restricting the algorithm executing ranges.And the nodes did not initially need knowledge of all the others in ADLE algorithm,which adapted it to the dynamic topology structures and the frequent node arrival/departure in Ad hoc networks.Analysis and simulation results show that it has lower message complexity,shorter response delay and better fairness than the traditional algorithms.关键词：distributed;leader election algorithm;Ad hoc;logical timestamp2|857|1更新时间：2025-07-16
- 摘要：This paper presents a novel vision-based method for finger-screen interaction which achieves natural interactions through moving and clicking a single finger on a computer screen.The method uses two cameras at different viewpoints to capture video images covering the computer screen in real time.We integrate two cues of skin color and contour information to track finger’s motions in the framework of particle filter.The clicking actions on the screen surface are detected with the obtained fingertip positions and the geometry parameters of cameras.Experimental results demonstrate that the interactive method can realize robust tracking of finger motion,against complex background and varying illumination conditions,as well as the instant detection of finger clicking actions.This method achieves robust and natural human-computer interaction,and can be widely used in many applications,such as intelligent interaction,digital entertainment and wearable computing environment.关键词：finger tracking;finger-screen interaction;human-computer interaction2|1646|12更新时间：2025-07-16
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