最新刊期
卷 29 ， 期 11 ， 2001
- 摘要：The area and speed of cryptography coprocessor impede the application of public-key cryptography RSA for smart card.A new VLSI architecture of high-radix modular multiplier to compute RSA public-key cryptosystem using our modified Montgomery algorithm is proposed.With TSMC 0.35μm CMOS technology models,a 1024-bit RSA cryptography coprocessor based on our proposed VLSI architecture have been implemented.Its simulation results show that the time to calculate 1024-bit modular multiplication is about 1216 clock cycles and the gate count of the coprocessor is about 38k.At a clock rate of 5MHz it will take about 374ms to encrypt 1024-bit message on average.Compared with previous works our proposed architecture can achieve good performance in chip area and speed,therefore it is well suited to smart cards.关键词：modular multiplier;smart card;public-key;modular multiplication2|1823|6更新时间：2025-07-16
- 摘要：A novel approach to embedding digital data into a cover image using simple Bézier curve is proposed on the base of harmonic amalgamation algorithm whose purpose is to hide digital images.A message embedded by this approach can be in the form of text,imagery,or any other digital signal.The data to be embedded is treated as a binary stream and is partitioned into a number of sub-streams.Each sub-stream of data is converted into values that are then embedded into the public original image.Given appropriate parameters,it could be proved that digital data embedded by this approach could all be recovered correctly by data recovering process with the knowledge of original image.The advantage of this approach is high efficiency of data hiding.Its maximal efficiency of data hiding could come up to 3 bits/pixel when using gray images as public original images.Experimental results show that the proposed approach is feasible.关键词：information hiding;data hiding;harmonic amalgamation2|940|2更新时间：2025-07-16
- 摘要：Programmable router not only forwards IP packets but also executes computing tasks.CPU scheduling in the programmable router is an important open problem till now.In this paper,the authors establish general software architecture of programmable router firstly.Based on the architecture,authors present a novel CPU scheduling algorithm based on queue length thresholds.We model this algorithm using stochastic Petri nets.The analysis results show that the scheduling algorithm can fulfill the requirements of computing of both best-effort flows and QoS flows in programmable router at the same time.关键词：programmable router;queue length thresholds;stochastic Petri nets2|1024|0更新时间：2025-07-16
- 摘要：A novel CMOS snapshot readout structure called DCA (Direct-injection Charge Amplifier) for focal-plane array (FPA) is presented in this paper.The pixel circuit includes only four MOS transistors.Using PMOSFET as the reset transistor with careful layout design,this pixel circuit not only can keep the in-pixel-capacitance large enough,but also can avoid the threshold voltage loss during the reset for the integration node.Thereby,charge capacity of the readout circuit is increased.Since the pixel circuit is very simple and this structure can eliminate the influence of column bus parasitic capacitance,it is very suitable for large-format small-pixel readout circuit.An experimental 128×128 DCA chip has been designed with 1.2-μm DPDM n-well CMOS technology.The charge handling capacity is 11.2pC with pixel size 50×50μm2.A description of the readout circuit structure,pixel circuit,detector model,operation principle and chip layout is given in detail.Both excellent simulation results and experimental results of the fabricated DCA readout chip are presented.关键词：focal plane array;readout circuit;direct injection;snapshot;DCA structure2|1196|2更新时间：2025-07-16
- 摘要：In this paper,we propose a novel buffer insertion theory for clock delay and skew minimization.Based on the Elmore delay model,buffer to buffer delay is a convex function of buffer positions in a clock tree.The optimal buffer placement for delay minimization is achieved when all delay functions have the same derivative values.The minimal skew can be obtained by equalizing delay functions of different source to sink paths.For a given clock routing tree,we initially insert the same level of buffers in all the source to sinks paths,then minimize the clock delay by optimizing buffer positions,and minimize skew by simultaneous buffer level augment and buffer sizing.关键词：clock distribution;buffer insertion;clock routing;clock delay;clock skew2|1104|2更新时间：2025-07-16
- 摘要：An extension of Equivalent Small Parameter(ESP) method to analysis of discontinuous conduction mode (DCM) PWM feedback controlled switching power converter systems is presented.The solutions are all symbolic expressions.关键词：switching power converter;discontinuous conduction mode;closed-loop systems;symbolic analysis3|987|2更新时间：2025-07-16
- 摘要：SHE (Substrate hot electron) enhanced breakdown characteristics of thin SiO2 are investigated by using SHE injection techniques.These experiments reveal that the average electron energy in the oxide depends on substrate voltage strongly.The average electron energy injected into oxide can be calculated by using the energy-conservation equation.The difference between SHE injection and F-N tunneling can be explained in terms of the caculated electron energy.A SHE enhanced TDDB model is presented in this paper.关键词：thin gate oxide;TDDB;SHE;charge to breakdown2|1323|0更新时间：2025-07-16
- 摘要：The effects of Simultaneous Switching Noise on VLSI have been elaborated.And an automatic CAD tool to optimize SSN performance of VLSI has been developed with optimized placement of inserting ground pads.Under the conditions provided by this paper,the equations in this procedure can be used in a very high-speed environment.A set of test chips taped out by using this CAD tool proved the procedure can effectively reduce the SSN,which is more serious when feature size of VLSI is scaled down.关键词：SSN(simulataneous switching noise);VLSI(very large scale integrated circuit);EDA(electronic design automation)2|945|1更新时间：2025-07-16
- 摘要：Lifting Scheme can be used to calculate Discrete Wavelet Transform (DWT) efficiently.It is composed of a number of lifting steps and the scaling transform.When it is used to calculate multi-level and multidimensional DWT,there exist many redundant multiplications.In this paper we propose,a new technique,called Post-Scaling Lifting Algorithm (PSLift),which needs fewer multiplications.The basic idea is first to calculate all lifting steps of each level and each dimensional DWT,and then calculate the scaling tranform.For example,when five level decompositions are implemented for Daubechies 9/7 biorthogonal wavelet,compared to the known methods,the number of multiplication needed is reduced by 20% and 28% compared to one dimensional DWT and two dimensional DWT.关键词：discrete wavelet transform;lifting;image compression;fast computation2|1051|10更新时间：2025-07-16
- 摘要：The Evolutionary strategy method is first introduced into parallel machine earliness/tardiness scheduling problem with common due date.Researches are made in the aspects of problem formulation,composite code of individual,dynamic fuzzy logic control of parameters of evolutionary strategy and local searching.Computational results of different scale problems show that the method can effectively solve the parallel machine scheduling problem with relatively large scale.关键词：parallel machine;scheduling;evolutionary strategy;composite code;fuzzy logic2|843|0更新时间：2025-07-16
- 摘要：A new genetic algorithm is studied for solving parallel machine scheduling problems with process constraint to minimize the total number of tardy jobs.A so-called vector-group coding method is presented,which shows the quality of coding simply,decoding fast and satisfying process constraints automatically.A new crossover operator named Extended Order Crossover (EOX) is then proposed,which has the merits of automatically satisfying procedure constraints and preserving much genetic information.Mutation,the other genetic operator,is implemented with the combination of bit-mutation and swap-mutation to keep the population diverse.The algorithm behaves more efficiently than others experimentally using various random data and application instance from practical production line.关键词：scheduling;parallel machine;process constraint;genetic algorithm;vector-group coding2|1276|11更新时间：2025-07-16
- 摘要：Identifying,representing and implementing the variability in domain engineering have a direct and important effect on application engineering;they are the emphases of domain engineering.Especially,building the reasonable and flexible DSSA (Domain Specific Software Architecture) in domain design,separating fixed parts and variable parts of systems,assigning the system elements between the DSSA and components reasonably,and implementing the variability as components are the nucleus and key work of domain engineering.This paper discusses the corresponding solutions to the variability of object-oriented domain design,employing the research results of design pattern and object-oriented framework;and presents how to use these solutions to deal with the variability in the domain design of POS (Point-of-Sale) domain.关键词：software reuse;software component;domain engineering;domain design;design pattern;variability2|1190|6更新时间：2025-07-16
- 摘要：This paper presents a new video segmentation algorithm based on spatio-temporal information.In spatial segmentation,we introduce a new watershed algorithm which has a high implementation speed.In motion segmentation,we put forward a new hierarchical block matching motion estimation algorithm.Finally we use the norm of the six affine parameters to merge the regions.The experimental results show that it is a robust and fast algorithm.关键词：video segmentation;watersheds transform;motion estimation;region merge2|1353|6更新时间：2025-07-16
- 摘要：This paper presents a fast layer-wise linearized algorithm for feedforward neural networks by mathematic methods with the following features:constructing target function for each layer by new methods;not calculating the Hessian matrix,thus greatly reducing the learning time.Simulation shows that the new algorithm can accelerate the convergence rate and reduce the error compared with the existing algorithms such as backpropagation (BP) algorithm,BP algorithm with momentum factor and existing layer-wise algorithms.关键词：feedforward neural networks;learning algorithm;OLL-algorithm2|1065|3更新时间：2025-07-16
- 摘要：This paper describes the implementation of integer lapped biorthogonal transform (binLBT) using lifting scheme and binDCT.The implemenation is in the forms of shifts and adds,so it is very fit for software and hardware implementions.Image coding experiments show that the binLBT is far superior to the DCT and the binary digit 9/7 wavelet which needs more operations,moreover,in subjective coding performance the binLBT is very competitive with the 9/7-tap biorthogonal wavelet.关键词：image compression;DCT;biorthogonal lapped transform;wavelet transform;fast computation2|1374|2更新时间：2025-07-16
- 摘要：This paper researches the problems of multicast video distribution in Internet.On discussing the characteristics of resource reservation protocol(RSVP) and the mechanism of the feedback agent, a new algorithm for multicast video distribution is proposed based on the layered video encoding.The simulation is performed using the network simulator ns-2.The results show that the algorithm not only assures the basic quality of service of the video applications,but also has better performance in fairness and scalability.关键词：multicast video distribution;RSVP;layered video encoding;feedback agent2|793|1更新时间：2025-07-16
- 摘要：Based on analysis of the conclusions in the statistical learning theory,especially the VC dimension of linear functions,linear programming SVMs are presented,including linear programming linear and nonlinear SVMs.In linear programming linear SVMs,the bound of the VC dimension is loosened properly.Simulation results for both artificial and real data show the generalization performance of our method is a good approximation of SVMs and the computation complexity is largely reduced by our method.关键词：statistical learning theory;VC dimension;support vector machines;generalization performance;linear programming2|993|6更新时间：2025-07-16
- 摘要：Output decay by thermal relaxation in perpendicular double-layered media is studied by numerical calculation and experiments. In addition some influences due to a single pole head are pointed out. We suggested that if these influences could be avoided, thermal relaxation in perpendicular magnetic recording would be much smaller than reported so far. High recording density and low noise is possible with relatively small particles, even at large film thickness in perpendicular magnetic recording.关键词：thermal relaxation;output decay;single pole head;perpendicular magnetic recording2|899|0更新时间：2025-07-16
- 摘要：Yield and reliability are two important factors affecting the development of semiconductor manufacturing.It is an important problem how to express the relation between yield and reliability.In this paper,a discrete yield model is given between yield and reliability,with many factors considered in this model,such as the line width,the spacing between the lines as well as the distribution of the defect size and so on.Finally,the validity of this model is shown by simulation.关键词：reliability;yield;distribution of the defect size2|1106|0更新时间：2025-07-16
- 摘要：A new approach to model the radiation-induced threshold voltage shift in fully-depleted SOI MOSFET has been implemented for circuit simulations.The model is validated by comparison of simulated and measured post-radiation device characteristics of MOSFETs in the literature.The model has such advantages as simple analytic expression,clear physical meaning,and easy extraction of used parameters.The model can be used as a basic circuit simulation tool for analysing hardened SOI MOS transistors exposed to a nuclear environment in the low-dose range.Additionally,the discussion presented here supports that the large top threshold voltage shift of the fully-depleted MOSFET is attributed to the large radiation induced oxide charge in the buried oxide which was coupled to the top gate.Thinner buried oxides,which are less dose sensitive than thicker ones,can not necessarily improve the radiation hardness of fully-depleted transistors because of the higher coupling effect.关键词：SOI MOSFET;radiation effects;threshold voltage shift model;dose rate2|1669|0更新时间：2025-07-16
- 摘要：The statistical properties of TDDB in 7.6~14.5nm gate oxide films under high stress field (＞11.8MV/cm) have been studied in this paper.It is proved that gate voltage increment at breakdown ΔVbd represents magnitude and position distribution of charge occupied traps,which reflects quality and uniformity of dielectric film.The calculated critical trap density Nbd by total charge to breakdown Qbd and ΔVbd is valuable for quantitative evaluation of the reliability of thin gate dielectric film.Experimental results show that Nbd of same thickness films is independent with field stress but related to film quality.It also shows that Nbd decreases with thinner films due to the statistical property of trap generation.Nbd is about 1020cm-3 with 10nm oxide films,which means dielectric breakdown occurs when trap density reaches 1% of the molecular density.As Nbd is an intrinsic indicator of reliability of thin dielectric films,it is more important in real applications than Qbd.关键词：thin dielectric film;critical trap density;reliability;defect statistical analysis2|1092|1更新时间：2025-07-16
- 摘要：A new Quasi-Multiple Medium (QMM) method is presented to accelerate computation of the direct boundary element method,and is applied to extraction of the 3-D interconnect capacitance with multiple dielectrics.Processing single dielectric as a combination of many quasi-multiple mediums,the QMM method produces much fewer non-zero entries in the coefficient matrix.As a result,the QMM method can greatly reduce the CPU time and save memory space used in the capacitance extraction.The QMM computation for several capacitors from actual layout is compared with that of non-QMM and Raphael,a famous commercial tool for parasitic capacitance extraction.The results of numerical experiments verify the analysis.关键词：VLSI;parasitic capacitance;direct boundary element method;quasi-multiple medium2|854|0更新时间：2025-07-16
- 摘要：Human face is a complicated curved surface.It may be more difficult to take a human face as a whole during face modeling.So in this paper we put forward a new method by which the surface of a human face is divided into some parts and every part is individually manipulated.At the same time,we take the human face as a elastomer and set up metamorphosable model for them.By this method we also have created a system in which a specific face model can be generated.And the algorithm we used in this system is characterized by higher efficiency and less interactive operations.Some satisfactory results from the system are given in this paper.关键词：face modeling;face subdivision;solid modeling2|945|1更新时间：2025-07-16
- 摘要：This paper analyses parameter characteristics of load network for class E power amplifier.The principle of "Parameter Compensation and Compress" and improved broadband load network are submitted.A broadband class E amplifier of 30~90 MHz is designed and produced according to the theory of circuit design optimization.The output power is 7.6~10.2W.Its total efficiency is 72%~84%.Tests show measurement results are basically coincident with theory calculation.关键词：class E;broadband;high efficiency;amplifier4|2332|2更新时间：2025-07-16
- 摘要：Firstly,the Diffserv QoS architecture and various edge router marking mechanisms and core router drop mechanisms are discussed in detail.Secondly,This paper examines the several analytic model studies and many simulations on TCP(Transport control protocol) performance in DiffServ Capable IP(Internet protocol) networks.Through analysis,we find that TCP flow using current DiffServ AF PHB can't always achieve assured rate whether by srTCM/trTCM or by TSWTCM.The factors that influence TCP performance are:RTT,target rate,TCP/UDP coexistence and the number of flows in aggregate.What wrong with DiffServ and TCP?We conclude that current DiffServ architecture needs to be enhanced and some per-flow state must be maintained to provide predictive fair service for TCP flows.关键词：QoS;DiffServ;marker;active queue management;TCP performance2|1085|5更新时间：2025-07-16
- 摘要：Currently the research on input-queued ATM switches is one of the most active research fields.The limiting throughput of it with input queue under the FCFS scheme is 0.59.Three policies are proposed to improve the throughout of switch:input expansion policy,window selection policy and cell discarding policy.In this paper,we study performance of these scheduling algorithms,and using simulation and numerical results,we get analytic formulas that are better than available formulas in practice.关键词：input-queued;ATM switch;scheduling policies;queueing system2|878|0更新时间：2025-07-16
- 摘要：Piezoelectric transformer is a kind of very promising solid electronic component which has the following several merits compared with the traditional magnetic transformers:it has very simple structure,small volume,high efficiency,no magnetic noise,no windings so uninflammable,high safety,and low cost under mass production.In this paper,the properties of piezoelectric transformer such as the step-up ratio of voltage,output power,efficiency,etc.are analyzed and calculated through equivalent circuit model.The accuracy of the model is verified by experiment.Two applications circuits:CCFL driver and DC-DC converter using piezoelectric transformer are given.关键词：piezoelectric transformer;equivalent circuit;DC-DC converter2|1258|8更新时间：2025-07-16
- 摘要：In order to support interactive services based on HFC networks,researchers have proposed several medium access control protocols,most of which adapt to reservation mechanism based on random access mechanism.The CDMA based HFC is a new generation of HFC system.In this paper,a CDMA-Reservation-Aloha access approach for the HFC network is proposed.Markov-chain system model is defined and a closed-form expression for the throughput is derived.Finally the steady-state numerical performances are analyzed.关键词：HFC network;MAC;multiple access;CDMA;CDMA-Reservation-Aloha;markov2|1105|3更新时间：2025-07-16
- 摘要：In this paper,the atomic component is introduced based on atomic functional model.The method to build optical network elements model using atomic components is proposed.Atomic components necessary to build the key network elements (i.e.OADM/OXC) are given,the result is presented also.The application of atomic components is demonstrated in simulation software of optical transport network.关键词：WDM;optical network;OADM;OXC;atomic functional model2|1031|0更新时间：2025-07-16
- 摘要：The definition of network survivability is presented.Then,the network survivability of SDH self-healing ring network under links failure is quantitatively analyzed.The relation between traffic distribution and network survivability and the effect of disaster on network survivability are studied.关键词：SDH;SHR;network survivability2|997|5更新时间：2025-07-16
- 摘要：Partition coefficient is a common method for clustering validity test.Based on the serious limitation of partition coefficient,modified definitions are given through a new point of view.Two new clustering validity functions are proposed using partition coefficient combined with total variation in fuzzy-partition.Experimental results show that the new methods have good classification performance.关键词：fuzzy partition;fuzzyc-mean clustering;clustering validity;partition coefficient2|1054|6更新时间：2025-07-16
- 摘要：A comprehensive and representative logical ring random service system with priority is discussed.It is asymmetric and the queue length and the upper limit of the service are all finite.The main contents include:the performance feature of the system;the transition characteristics of the queue states;the approximate algorithm of the transition probability of the queue states;the unconventional algorithm of the state probabilities of the queues etc.New concepts such as the state conditional transition and the state transition combination,and the methods of substituting the distribution parameters by the lumped ones are proposed in the paper.关键词：logical ring;state conditinal transition;state transition combination;Markov-Chain2|874|1更新时间：2025-07-16
- 摘要：Programming technology has been applied in industry,traffic,chemical plant and cosmonautics et al.The author established fuzzy linear programming (FLP) model for feed formula in light of feature of animal growth.A new version of feed formula software has been developed basing on the original one.The new software is better than similar system inside and outside China for its fuzzy programming technology.FLP can decrease the cost of feed compared with linear programming (LP) and objects programming (OP).This paper contrasted and analyzed the results of three optimizing models.关键词：fuzzy linear programming (FLP);Feed formula;linear programming (LP);objects programming (OP)2|1732|2更新时间：2025-07-16
- 摘要：Theory and applications of the composite soft-switching technique are presented,based on the snubber and resonant soft-switching techniques.Four configurations of the power converters are obtained by using composite soft-switching topology.A practical composite soft-switching topology for single-phase full bridge inverter is observed,which employs fairly simplified circuit configuration and control pattern.Simulated and experimental results verify the effectiveness of the proposed soft switching technique.关键词：snubber;resonant soft-switching;composite soft-switching;inverters4|1056|2更新时间：2025-07-16
- 摘要：Software development processes,as a means to ensure software quality and productivity,have been widely accepted within the software development community.This research introduces how to assist developers to establish quality management plan and monitor the implementation of software processes quantitatively in a CASE environment.A PSEE (process-centered software engineering environment) named Softev has been brought forward to provide developers the environment to define,execute and monitor their processes.As UML is becoming a standard diagrammatic notation for object-oriented modeling and is spreading rapidly,it has been chosen to express the artifacts developed during the requirement analysis and system design stages.In the early products of software process engineering,there was not enough attention to be given to the metrics of software processes and artifacts.This research proposes a suite of metrics and gives the implementation in Softev.Managers are able to predict and supervise the software project more precisely.关键词：software process;quality control;UML;metrics4|930|1更新时间：2025-07-16
- 摘要：We propose the concept of access structure with transfer property,and suggest a general method of constructing secret sharing schemes with this kind of access structures.Our method is simple and practical.Even if a participant is contained in many minimal authorized subsets he needs not to keep more than one secret shares for sharing one secret.There is no need for a participant to keep extra secret data when multiple secrets are to be shared.So our method has advantages over many others.An example is given to show concretely how to construct secret sharing schemes with such access structures.关键词：secret sharing;access structure;minimal authorized subset;linear independence2|887|6更新时间：2025-07-16
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