最新刊期
卷 33 ， 期 11 ， 2005
- 摘要：The resonant switched capacitor (RSC) converter with zero-current switching (ZCS) is a new topology of switched capacitor converter.This paper studied the influence of circuit parasitic parameters and operating conditions on the RSC converter steady-state characteristic.The mathematical expressions of the average output voltage and efficiency were derived for the first time,which were helpful to analyze the RSC converter performance regarding the loading effect and the variation of input voltage.A frequency control method for RSC converters was achieved based on the output voltage expression.A step-down RSC converter was used as an example to describe the equation derivation.The similar steady-state analysis could be applied to other types of ZCS RSC converters.Finally,experimental results on a 12V/5V/2.5A prototype are found to be nearly in accordance with the theoretical results.关键词：switched capacitor converter;zero current switching;resonant;steady state characteristic2|965|4更新时间：2025-07-16
- 摘要：An incremental approach to lear ning Bayesian networks based on genetic algorithm,namely ILBN,is put forward in this paper.ILBN introduces the EM algorithm and genetic algorithm into the incremental process of Bayesian network lear ning,calculates the expectation of the sufficient statistics with incomplete data using EM algorithm and evolves network structures using genetic algorithm,that could avoid getting into local maxima to some extent.Furthermore,by defining a new mutation operator and extending the traditional crossover operator,ILBN could incrementally lear n and evolve Bayesian networks containing hidden variables.Finally,ILBN improves the incremental process by Friedman et al.The experimental results show that,in terms of storage cost,ILBN is comparable with the method by Friedman et al,while under the same experimental conditions,ILBN could lear n more accurate networks than that of Friedman et al.The experimental results also verify the validity of ILBN in presence of incomplete data and hidden variables.关键词：Bayesian networks;incremental lear ning;genetic algorithm;hidden variables2|2001|6更新时间：2025-07-16
- 摘要：Latency is a key performance parameter and utilization indicator for providing QoS guarantees and monitoring network performance.In general,monitoring schemes to measure latency are,divided into two types,active and passive monitoring.Unfortunately,both types have drawbacks.The method of combining passive and active approaches uses the latency gained by active measurement as an estimator of the latency of user packets,with weight adjusted by the number of user packets obtained by passive monitoring.This effective method has some advantages such as protocol-independent,negligible extra traffic,convenience and being able to estimate individual user performance.This method considering the number of user data packets arriving between probe packets and the latency alteration of neighborhood probe packets,could reflect the actual network status more exactly,especially in the case of network congestion and packet loss.关键词：network monitor;measuring latency;active measurement;passive calibration2|1155|1更新时间：2025-07-16
- 摘要：Linear pixel unmixing is one of the key technologies for hyperspectral image application.However,there are two problems for the hyperspectral decomposition in operational cases.One is the endmembers of an image can't be extracted automatically with traditional supervised ways;the other is unmixing hundreds of spectral bands directly may reduce accuracies due to the high correlation between bands.To mitigate the problems,we proposed a method for abundance estimation from spectral domain wavelet features.We utilized the discrete wavelet transform (DWT) as a preprocessing step for the feature extraction,then selected endmembers with projective iterative algorithm in an unsupervised fashion based on the features.In the end,we performed a constrained least square method for the abundance estimation.Algorithm validation and comparison were done with real PHI data.Experimental results show that the use of DWT-based features can improve the abundance estimation,as compared to those of original hyperspectral signals or conventional PCA-based features.关键词：wavelet feature;spectral unmixing;endmember extraction;iterative projection2|890|4更新时间：2025-07-16
- 摘要：To improve embedded multimedia application performance and reduce power consumption,an efficient method of exploiting scratchpad memory is proposed.Big data array are divided in small tiles and copied to on-chip memory by stages.Data in scratchpad memory should be reused as much as possible to reduce data transfer between off-chip memory and scratchpad memory. Memory access delay can be avoided by proper assignment of memory operand in assemble instructions.Some operand memory constraint conditions can be listed out to minimize pipeline stall.A method of array assignment is proposed in these conditions.2|1775|0更新时间：2025-07-16
- 摘要：A New method for camera calibration using template is proposed.This method requires camera to take the template picture from three different positions.Through cor ner extraction and circular points calculation,the camera's intrinsic parameters can be obtained linearly,and its extrinsic parameters can also be calculated.Simulation and real experimental data all verify that it has the characteristic of simplicity,convenience and accuracy.关键词：camera calibration;circular points;cor ner extraction;intrinsic parameter;extrinsic parameter2|1478|7更新时间：2025-07-16
- 摘要：New extension of instruction set and new add-on function unit can improve the performance of microprocessor greatly.All the applications should be recompiled and rebuilt,otherwise they can't benefit from those new instructions.This paper proposes a framework of multi-level dynamic optimization,which introduces instruction scheduling and optimizing for the architecture extension based on trace-cache in runtime.Experimental results show that it can enlarge the instruction window to select hot codes and scheduling methods efficiently and effectively,and leverage the performance of original application without the need of recompiling.In addition,this framework is flexible and scalable to new optimizing chance and various platforms.关键词：trace;dynamic optimization;instruction scheduling;ILP2|739|3更新时间：2025-07-16
- 摘要：Active Integrated antenna arrays are designed by use of York's nonlinear dynamic theory and spatial power combining is realized.Through changing the oscillating frequencies of active elements,the beam scanning from -10°~10° is realized without phase shifters.The measurement data and theory values have a good agreement.关键词：active integrated antenna array;nonlinear dynamic theory;spatial power combining;beam scanning2|1054|2更新时间：2025-07-16
- 摘要：Modularity is an important procedure for improving the design methodology and the design ability of VLSI.Modularity has the merits for predigesting design,shortening the period of design,reducing the design cost,reusing the design,partitioning software and hardware,and so on.The existing algorithms for settling the problem of template generation are analyzed.A regularity extraction algorithm is presented,which can generate all the templates of a circuit.The algorithm is independent on the structure of circuits and modules.An algorithm is also put forward which can select part of the templates to cover the circuit under some situations,and the experiment results of the algorithms are also given.关键词：template;modularity;regularity;control data flow graph2|788|2更新时间：2025-07-16
- 摘要：The random variations of technological parameters are always existent during manufacturing,which have a definite impact on transmission performance of transmission lines.Considering the impact,the stochastic model for transmission lines is proposed,and the precise integration algorithm is combined with Monte Carlo method to analyze the transient response of the stochastic model.Jarque-Bera test is made for the normality of the model's output and the worst-case estimation is given.In the case of sinusoidal excitation,lossless transmission lines are considered.The analytic form of first moment of the corresponding stochastic differential equation's solution is derived,and the numerical computation method for second moment is given,finally the upper and lower bound of the output signal's amplitude and phase shift is estimated.Experimental results demonstrate that the proposed stochastic model and the statistical analysis method can evaluate the transmission performance of transmission lines effectively.关键词：transmission line;telegrapher's equation;stochastic modeling;stochastic difference equation;Monte Carlo Method5|1041|11更新时间：2025-07-16
- 摘要：The defect is a main factor of affecting IC's yield and reliability.Defects can be divided into yield defects (hard faults),reliability defects (soft faults) and goodness defects based on the difference between the defect's concept and fault's concept.The probability of a defect being a hard fault or a soft fault by the critical area of a defect is given and a more accurate yield model is gotten.A quantitative expression between IC's failure probability and functional yield is obtained by the relationship between the yield defects and reliability defects.IC's failure probability can be estimated by this quantitative expression using this IC manufacturing yield,and the research and development period can be shortened.关键词：yield;failure;defect;soft fault;hard fault2|1087|4更新时间：2025-07-16
- 摘要：A communication environment for multi-robot system,ERobix,is introduced to support the redeployable architecture.Based on this communication environment,a method of available capacity estimation for shared computing resource in multi-robot system is proposed.This method exploits the queuing delay information of a set of data units dispatched with the increasing time spacing to estimate the available computing capacity.The result of experiment shows that this method is stable and reliable for architecture validation or task scheduling of multi-robot system.关键词：multi-robot system;redeployable architecture;available capacity estimation2|838|2更新时间：2025-07-16
- 摘要：This paper presents a compression and decompression scheme based on run-length codes for reducing the amount of test data.We refer to this hybrid run-length codes,it has the excellent advantages of high compression ratios,robust and low area overhead.Since the compression ratios strongly depend on the strategy of mapping which doesn't care in the original test set to zeros or ones,we also present an Iterative Sort Filling algorithm to find the best assignment method which minimizes the total size of the test data and achieves higher compression ratio.The theoretical analysis and the experimental results for ISCAS 89 benchmark circuits demonstrated the compression efficiency of the proposed hybrid run-length codes and Iterative Sort Filling algorithm.关键词：test data compression;don't care assignment;system-on-a-chip test;hybrid run-length codes2|998|19更新时间：2025-07-16
- 摘要：The paper presents the effectiveness of EMI suppression of switching converters with a chaotic frequency modulation scheme.Arguments are given highlighting the link between the spectrum of the modulated signal and the invariant probability density function of the chaotic system generating the modulating signal.A simple Ber noulli-map chaotic circuit is designed and adopted as the modulating signal source.The discrete-time chaotic signal is incorporated into the Boost converter operating in the double-loop control mode,thus the switching frequency varies randomly with the chaotic signal.The experimental results have confirmed the advantage of the proposed method and its applicability for switching converters.关键词：chaotic frequency modulation;EMI;Ber noulli map;chaotic circuit2|841|1更新时间：2025-07-16
- 摘要：This algorithm expands all prefixes to three kinds of lengths according to the prefixes distribution of route tables.And several Hash functions are selected by using the maximum entropy criterion method proposed in this paper,then map the expanded prefixes to different levels of three Hash tables.In process of IP routing lookup,the algorithm dynamically calculates the searching cost using the hit rate of the three Hash tables,and then adjusts its searching sequence accordingly.The algorithm supports increasing update,and is easy to be implemented in software or pipelined hardware.The experiment demonstrates that it needs less than 3.7 M bytes for the real route tables of 128K prefixes,and averagely it needs only 1.1 memory accesses for each lookup and few memory accesses for each update.关键词：dynamic IP routing lookup;limited prefix expansion;hash;maximum entropy criterion method2|822|0更新时间：2025-07-16
- 摘要：Traditional researches on the stability of multicast tree mainly focuses on the dynamic change of multicast members.But in application level multicast (ALM),where the multicast tree is constructed on end systems in the application layer,multicast members can cheat in order to improve their positions in the multicast tree,which may result in the instability of multicast tree even with stable members.This paper establishes the cheating model of ALM nodes,and discusses the instability problem of ALM tree on the occurrence of node cheating when there is no multicast member changing.The simulation results show that node cheating will bring considerable neglect impact on the stability of ALM tree.关键词：multicast;application level multicast;node cheating;stability2|731|1更新时间：2025-07-16
- 摘要：RTD SPICE model is built and fit to the actual RTD device fabricated on GaAs substrate.The principle of the four value quantizer circuit is explained and the simulation work is done through the extraction of device parameters.The key parameters of the circuit are established.The calculated threshold voltages of the circuit are conformed to the simulation results.Finally the maximum working frequency of the circuit is analyzed.关键词：resonant tunneling diodes (RTDs);Quantizer;multiple value logic (MVL);SPICE2|1009|0更新时间：2025-07-16
- 摘要：Low temperature co-fired ceramics (LTCC) technology and three dimensional (3D) microwave cubic packaging technology for microwave modules are effective methods for realizing microwave modules miniature and light with high performance and high reliability.In this paper,3D integrated microwave modules based on LTCC are studied and developed.The cubic interconnecting structure of 3D integrated microwave modules,the vertical microwave interconnecting of 3D integrated LTCC microwave circuit substrates,and the vertical microwave interconnecting of microwave multi-chip module (MMCM) are described in detail.The volume and weight of 3D integrated microwave modules with these technologies are reduced by 40% and 38% respectively compared to traditional 2D LTCC integrated microwave modules,and the electric performances are about the same.关键词：low temperature co-fired ceramics (LTCC);vertical microwave interconnecting;3D cubic packaging;microwave module2|1523|13更新时间：2025-07-16
- 摘要：We propose a fault tolerance AES hardware implementation to prevent attackers from injecting faults in the process of AES design.The design adds Hamming Code error correction circuits into the original AES implementation and it can correct all single-fault in the same byte automatically.Hardware simulation shows that the ratio of fault detection is close to 100%.The results of analyzing of different architecture and configuration of check points certificate that our proposal is very practical.关键词：advanced encryption standard(AES);hamming code;fault tolerance;error correcting codes;fault detection2|912|3更新时间：2025-07-16
- 摘要：This paper presents a hybrid GEP parallel algorithm,which combines simulated annealing and genetic mechanism to avoid the problem of premature convergence.Meanwhile,it imports multi-population strategy and migration operator,and a coarse-grained parallel computing on finite number of CPUs is implemented.Experiments on sequence induction,function finding and sunspot prediction show that the algorithm has better search ability and higher stability than basic GEP.关键词：gene expression programming;simulate annealing;multi population strategy;MPI;parallel algorithm;symbolic regression2|1098|10更新时间：2025-07-16
- 摘要：Multipath Routing is more suitable than single route for systems such as tactical radio networks because it can efficiently support fault-tolerance,load balancing and QoS.In addtion,anonymity should be one important part of overall solution for those in which confidentiality,integrity and availability should be realized as basic security.Whereas those anonymous secure routing protocols known in MANET can't protect routing from passive attacks and byzantine behavior and can't provide mutilpath either,we adopt incomparable public keys cryptosystem,Bloom Filter,lightweight onion shuffle algorithm and reinforcement lear ning paradigm to design anonymous secure multipath routing protocol.We validate the effectiveness of our design using extensive simulation and detailedly analyze the security and anonymity as defined.关键词：multipath routing;reinforcement lear ning;bloom filter;incomparable public keys cryptosystem;anonymity;MANET2|1200|7更新时间：2025-07-16
- 摘要：The scheme of tracking maneuvering target based on neural fuzzy network with increased leaning is proposed. When tracked target maneuver occurs,the scheme can detected maneuver immediately to estimate the maneuver value accurately,then the tracking filter can be compensates correctly and duly by the estimated the maneuver value and system covariance.When environment changed,neural fuzzy network with increased leaning can find its optimal structure and parameters automatically to adopt to changed environment,and always produces estimated output very close to the true maneuver value that lead to good tracking performance and avoid miss-tracking when tracked target maneuver occurs.Results of simulation show that the performance is superior to the traditional schemes and the scheme can fit changed dynamic environment to track maneuver target accurately and duly.关键词：neural fuzzy network;increased leaning;target maneuver2|843|0更新时间：2025-07-16
- 摘要：TengYue-1 is a microprocessor subsystem for embedded applications.Its heart is a 32-bit RISC microprocessor based on an instruction set architecture (ISA) designed by us.Through a WISHBONE compatible on-chip bus,the microprocessor,a universal memory controller,a LCD controller and other peripheral I/Os formed the SOC.TengYue-1 has been implemented and verified in SMIC 0.18μm CMOS technology,and the maximum clock frequency is 300MHz@1.8V.This paper presents the design and implementation of TengYue-1.We used 9 ARM benchmarks to evaluate the performance of the microprocessor and the results showed that it met our goal.We also found a simple solution to the memory access conflict problem caused by the microprocessor core and the LCD controller.关键词：SoC;embedded microprocessor;architecture;pipeline;cache;memory controller2|886|3更新时间：2025-07-16
- 摘要：As a promising switching paradigm,Optical Burst Switch (OBS) was proposed for optical networks showing higher efficiency and shorter delay than traditional circuit switching,and it is more feasible than optical packet switching.In OBS,burst assembly is one of the critical technologies,and will significantly affect the performance of networks.In this paper,we focus on the study of burst assembly mechanism,and propose a new burst assembly algorithm,which reduces the self-similarity of IP traffic,enhances the data burst utilization and avoids the bandwidth contention due to sending burst data synchronously at different ingress nodes.关键词：optical burst switching;assembly;threshold;self-similarity;ON /OFF sources2|770|3更新时间：2025-07-16
- 摘要：A new method for image de-noising which colligated the strongpoint of Contourlet transform and Recursive Cycle Spinning was presented.Due to the lack of translation invariance of the Contourlet transform,image de-noising by coefficient thresholding would lead to Gibbs-like phenomena(lead to artifacts).Recursive Cycle Spinning was employed to avoid the artifacts.The experimental results indicate that the method can get better visual effect and PSNR value compared with the methods like wavelet image de-noising using the Recursive Cycle Spinning.关键词：wavelet transform;contourlet transform;recursive cycle spinning;image de-noising2|1281|16更新时间：2025-07-16
- 摘要：Hydrosol of Fe(OH)3 prepared by rapid thermal hydrolyzation was used to create a precursor of iron nano-particle,which could catalyse the growth of carbon nanotube in a CVD process.Randomly distributed and aligned carbon nanotubes film were prepared by this technique.These carbon nanotube films were applied in a prototype of field emission display.Field emission characteristics,especially its field emission stability and degradation with time,were tested in detail.The field emission current fluctuated significantly at the beginning of the test.After about twenty hours ageing process,fluctuation of the current was decreased significantly.After the ageing process,1mA/cm2 was achieved under 3.7v/μm.15000h lifetime with a degradation within 30% was confirmed by a detailed lifetime test over 20000h.关键词：carbon nanotube;hydrosol;field emission displaylifetime2|752|1更新时间：2025-07-16
- 摘要：This paper presented a single-bit fourth-order sigma delta modulator for dual-standard receiver.The low voltage and low power target is attained by improving the modulator structure and optimizing from system to circuit blocks.Hspice and Matlab co-simulation with 0.35μm CMOS technology indates that dynamic range is 86dB for GSM,36dB for WCDMA respectively and power dissipation is only 10.5mW and 12mW with 2V power supply.关键词：bandpass sigma delta modulation;low power;low voltage operational amplifier;bootstraped switch2|1293|2更新时间：2025-07-16
- 摘要：The electron-sheet-density in the quantum well of Strain-Si modulation-doped NMOSFET(Metal-Oxide-Silicon Field Effect Transistor)affects switch performance.The model of electron-sheet-density in Strain-Si modulation-doped NMOSFET quantum well is established by solving Poisson equations,and the model of the threshold voltage is established. Then the models are analyzed by MATLAB when the device is static.The relations of the δ-doping-layer concentration and the space layer thickness to the electron-sheet-density and the threshold voltage are also discussed at static state.The influences of physical parameters of material and structure parameters of device on the electron-sheet-density and the threshold voltage are analyzed by using MATLAB.With decreasing δ-doping-layer concentration and increasing the space layer thickness,the electron-sheet-density and the absolute value of threshold voltage decrease.关键词：strain Si;modulation-doped;electron-sheet-density;threshold voltage2|996|1更新时间：2025-07-16
- 摘要：A technique for classification of galaxy spectra is proposed.At first,a four-level wavelet decomposition of the original spectrum is performed,and the wavelet coefficient at the fourth level,which mainly includes the information of spectral lines,is chosen as the wavelet feature of the spectrum.Secondly,principal components analysis is used to compress the wavelet feature and to get the recognition feature of the spectrum.Finally,Fisher linear discriminant analysis is employed for classification.This approach can recognize the galaxy spectrum whose flux is uncalibrated and redshift is unknown.Comparisons with several other classification techniques were made by experiments.Experiment results show the proposed method is robust and superior to other methods under the condition that flux is uncalibrated.关键词：spectral classification;wavelet feature;principal components analysis;Fisher linear discriminant analysis2|1108|9更新时间：2025-07-16
- 摘要：Based on the cryptosystem of ElGamal-like,this paper presents a new anonymous fingerprinting scheme without third party.Without involving any third party,this scheme helps merchants to verify the identity of anonymous buyers in order that only buyers registered can get the digital product.At the same time,merchants can trace back to the real pirate from a confiscated illegal copy without the buyer’s participation.Moreover,this scheme has the properties of unlinkable and frame-proofing.The safety of this scheme is based on the intractable problem of solving Discrete Logarithm.关键词：anonymous fingerprinting;copyright protection;certification;tracing4|724|0更新时间：2025-07-16
- 摘要：System-level diagnosis was introduced into the fault diagnosis for satellite networks.A novel modeling method for satellite networks,two-level-node graph,was presented to characterize the specialty that a satellite could have more than one communication directions and its communication function could be faulty partly.Then a strategy of the system-level fault diagnosis for satellite networks was designed based on broadcast and its communication complexity was analyzed theoretically.The satellites' broadcast and one to many communication modes were taken advantage of when testing so that our strategy is applicable to arbitrary topology and saves communication overhead.Simulation results show that the communication overhead reduces while the number of ports,which can communicate,decreases.关键词：system-level diagnosis;fault detection;fault diagnosis;satellite networks;two-level-node graph2|714|0更新时间：2025-07-16
- 摘要：A new signcryption scheme is developed based on Domain-verifiable signcryption .The scheme simultaneously fulfills both signature and encryption in a single logical step at a lower computational cost.In particular,it can be used by certified mail protocol,and based on the scheme a multi-party certified mail protocol is proposed,its fairness and non-repudiation are proved.关键词：fair exchange;one-to-more certified mail protocol;signcryption;fairness;non-repudiation2|910|7更新时间：2025-07-16
- 摘要：In this paper,using a very long instruction word (VLIW) architecture view,the existing state of the art algorithms were compared with an algorithm that is tailored for VLIW architecture in the form of matrix.The architecture's character is further exploited to design a new fast inverse discrete cosine transform (IDCT) algorithm.Compared with existing algorithms,the new algorithm reduces the number of instruction cycles needed.Further,the register character of VLIW is used for merging motion compensation with IDCT (DCT) in the video codec process.This achieves 50% speed improvement.The concept is applicable for MPEG1/2/4 and H.264/AVC.关键词：very long instruction word (VLIW);discrete Cosine transform (DCT);IDCT;fast algorithm;parallel algorithm;motion compensation;video compression;DSP2|752|1更新时间：2025-07-16
- 摘要：Rough set is a valid mathematical theory developed in recent years,which has the ability to deal with imprecise,uncertain,and vague information.The core and reduction of attributes are two important topics in the research on rough set theory.It has been proven that computing all the reductions and the optimal (minimal) reduction of decision table is a NP-hard problem.In this paper,Rough set theory is deeply investigated;a number of useful properties of the positive region are discovered.Based on the above findings,we present a calculation algorithm for core directly.And then,two algorithms for relative reduction based on the positive region are designed.关键词：rough set theory;finding core;relative reduction;decision table2|1729|31更新时间：2025-07-16
- 摘要：Through experiments,it is found that HSTCP has severe RTT unfairness,as well as many dropped packets in a congestion event.After analyzing the RTT unfairness in HSTCP with a model and the reason of packet loss,we propose CB-HSTCP that includes CW and Block-pacing algorithm to alleviate RTT unfairness and reduce the number of lost packets.To evaluate the performance of proposed algorithm,a relative fair criterion is proposed.Simulation results with ns2 show that our new proposal can solve the RTT unfair problem,reduce packets loss rate meanwhile keeping advantages of HSTCP such as good scalability and TCP friendliness.关键词：high-speed networks;TCP;HSTCP;congestion control2|714|2更新时间：2025-07-16
- 摘要：PLS inherits the merits of both topology driven and flow driven label distribution scheme.It can greatly improve the performance of router when label space is constrained.Some parameters,including scan window,damp factor,upper threshold and low threshold,are used in PLS.To achieve the best performance for router,the value of scan window should be sixty seconds.And the values of upper threshold and lower threshold should adapt to the size of label space and network traffic,which also are linear with the value of damp factor.关键词：Multi-protocol label switching(MPLS);label space;forwarding performance2|682|0更新时间：2025-07-16
- 摘要：Currently it is difficult for search engine to rank effectively.This paper proposes a ranking method of search engines.The method applies collaborative filtering based on the retrieved results from the users in the same community.A parallel algorithm for mining association rules is described to preprocess all users' local directed graphs to find the commonly interesting pages for the users in the same community.Web pages contents,hyperlink structures and the associated texts are then analyzed.Authority pages and hub pages are recognized to discover the related results not found by the search engines.In addition,the evaluation of the web pages is based on not only the hyperlink structures and the query user's evaluation,but also the evaluation of other users in the same community and the usage of the pages by all users.As a result,the ranking method of the search engine is reasonable and effective.关键词：information retrieval;search engine;data mining;collaborative filtering2|877|2更新时间：2025-07-16
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