最新刊期
卷 35 ， 期 8 ， 2007
- 摘要：The degradation method of diphenyl ketone and TOC(Total Organic Carbon) in lithographic waste water. By using 185nmUV irradiation has been studied. The effectiveness of diphenyl ketoneby 185nmUV and 254 nmUV irradiation has been compared. In addition the intermediate products and process have been investigated. The aim of abatement of diphenyl ketone waste water was achieved.关键词：185nmUV;254nmUV;diphenyl ketone;degradation;intermadiate2|1595|1更新时间：2025-07-16
- 摘要：A method used to remove the nonlinear error in a digital PWM structure is introduced. This method is based on correction factors added to each integrator of delta-sigma modulator. A design example is presented,and the simulation result indicate this method can remove the nonlinear error completely.关键词：PWM(pulse width modulation);nonlinear error;delta-sigma2|1929|5更新时间：2025-07-16
- 摘要：PI controller is often used to control active queue management(AQM),but its trial method of tuning controller is aimless,and the dynamic performance of algorithm is not enough satisfying.Simplified network model based on fluid flow theory is derived in this paper,and based on this model,an improved algorithm,i.e.particle swarm optimization (PSO) algorithm is applied to optimization of PID controller parameters.In the following,a new performance function including the system adjusting time,rise time,overshoot,steady state error and sinusoidal position tracking error is defined.It is fast to calculate a group of PID controller parameters that minimize the evaluation function by searching in the given controller parameter area,and then the PID controller is applied to AQM system.The simulation experimental results show that under the two conditions of large time delay and sudden business flow,the overshoot is both less than 5%,the adjusting time is less than 5 seconds and 4 seconds separately,and the steady error is less than 2 packets and 3 packets separately,so the dynamic state and steady state performances of the proposed algorithm are obviously superior to those of the existing RED and PI algorithms under the two conditions.关键词：active queue management;network congestion;PID control;particle swarm optimization2|1375|7更新时间：2025-07-16
- 摘要：It is one of the important study tasks for negotiation optimization to solve negotiation deadlocks.In order to get rid of such deadlocks in the time-limited bilateral and multi-issue autonomous negotiation,a multi-objective particle swarm optimization algorithm,called MOPSO,is put forward in this paper.MOPSO makes full use of the relationship among issues and first relaxes the reserved value of the issue dynamically which triggers the negotiation deadlock.Then the algorithm translates the problem of tightening the reserved values of the issues relevant to the deadlock issue into a multi-objective optimization one and turns up a Pareto-optimal set by a particle swarm.In this way,these reserved values are optimized in parallel and the algorithm lastly replaces the old reserved vector of the negotiation issues with a new one equivalently,which keeps the level of the integrated utility of the negotiant.The obtained results of experiments on E-commerce support the claim that MOPSO is valid and it is preferable to the existing method in solving the problem of the negotiation deadlocks.关键词：multi-issue negotiation;negotiation deadlock;particle swarm optimization;multi-objective optimization2|1300|6更新时间：2025-07-16
- 摘要：Using the ensemble Monte Carlo method,we have simulated the THz temporal waveforms from narrow-gap semiconductor n-InAs and wide-gap semiconductor n-GaAs.The radiation mechanism for n-InAs is confirmed as the photo-Dember field,and the reason for the higher radiation efficiency of n-InAs than that of n-GaAs is:in the area occupied by the major part of photo-generated carriers,the electric field in n-GaAs is much smaller than that in n-InAs.This reason was not mentioned in all previous studies.关键词：n-InAs;n-GaAs;THz radiation;Monte Carlo simulation2|1160|0更新时间：2025-07-16
- 摘要：This paper applied Giant Magneto Resistive (GMR) current sensing method in a current-driven synchronous rectifier.Comparing with the conventional current sensors,GMR current sensor can overcome the drawbacks of large loss,no DC capability,large leakage inductance and low switching frequency.The current sensing theory of GMR current sensor was discussed and a current-driven synchronous Forward converter with GMR current sensor was provided.The experimental results show that the performance of the modified Forward converter is good and its efficiency at light load is improved.关键词：giant magneto resistive(GMR);synchronous rectifier;current-driven;no-load efficiency;current sensing2|1512|1更新时间：2025-07-16
- 摘要：Based on the characteristics of the hardware scheduling,a scheduling model for the periodic and un-periodic threads in hardware scheduling is proposed.The criterion of the successfully scheduled threads is presented by mathematical description.On this basis,the DR-EDF algorithm based on the deadline and the difference of the worst executing time is proposed.The design of thread-scheduling controller using the DR-EDF is brought forward.And the processor based on the DR-EDF algorithm is achieved on an FPGA.The results of experiment show that the scheduling failure rate will not be affected and scheduling-ability for emergency threads is improved.关键词：Preemption model;earliest deadline first(EDF);dynamic rate earliest deadline first(DR-EDF);hardware-thread;real-time scheduling2|1307|1更新时间：2025-07-16
- 摘要：According to the response of the thin wire array to the incident electromagnetic wave and the equivalence relation of uniform medium and uniform transmission line,the equivalent circuit for the thin wire array of metameterial is presented while a plane wave is propagating through it.The effective permittivity model of the asymmetric wire array is derived based on the circuit theory.And the validity of the model is proven by the numerical simulation.The description of theoretical derivation exhibits clear physical concepts and provides a new approach to understand the minus permittivity effect of the thin wires array from the macrophysics.关键词：metamaterial;equivalent circuit;wire array2|1390|0更新时间：2025-07-16
- 摘要：This paper presents a fuzzy mathematic model for data association applying to the passive sensor network and defines the fuzzy synthetic closeness.Based on the fuzzy synthetic closeness,a fuzzy track initiation algorithm is proposed.The selection of the starting points for searching in the steepest descent algorithm,the initial state estimation of the candidate targets,and the methods for target detection and multivalency processing are also discussed.The advantage of the proposed algorithm over the algorithms available is that it isn’t necessary to know the distributed characteristic of the clutter and the detection probability of target.Simulation results show the proposed algorithm can initiate the tracks effectively.关键词：data fusion;data association;passive sensor;track initiation;fuzzy set2|1044|7更新时间：2025-07-16
- 摘要：It is analyzed about the damage mechanism of ionization and displacement radiation on CCDs,The physical model and the numerical processing method are set up about a buried channel CCD,which has been used to simulate the dynamic transfer process of CCD with the three phrases pulse driver by semiconductor device simulator MEDICI.It is also calculated on the charge transfer efficiency of CCDs irradiated by 1MeV and 14MeV neutrons.An offline measure system is designed for radiation damage effects on linear CCDs based on CPLD.The experiments of ionization and displacement radiation effects are carried out on the commercial linear CCD by Co-60 γ source and neutron pulse from Xi’an Pulse Reaction with our self-designed test system,and get some valuable results of dark voltage and saturation voltage and charge transfer efficiency and cells inequality varied with total dose and neutron fluence for the devices.关键词：CCD(charge coupled device);radiation effect;mechanism analysis;simulation experiment2|1416|3更新时间：2025-07-16
- 摘要：Negotiation is an important method to coalition formation in MAS.Most of existing work seldom studies how to generate initial proposals.A strategy based on historic behavior to decide initial proposals is proposed.By evaluating each agent's contribution ratio in historic tasks,the expected profit factor to the current job can be attained and based on it the initial proposal is obtained.Moreover,a coalition formation strategy is presented.Experimental results demonstrate that this method is efficient.关键词：initial proposals;contribution ratio in capabilities;expected profit factor;historic behavior2|923|1更新时间：2025-07-16
- 摘要：The encoding problem is a most fundamental issue in DNA based computing.Its difficulty lies in how can we assure that each code could accurately identify itself in linear DNA sequences.Therefore,how to use those codes effectively becomes an urgent problem.In this paper,we introduce the concept of template frame and its shift distance property based on the template strategy.Then,we study the influence of the length of labels,single labels and multiple labels on the shift distance.The result shows that the multiple label method can improve the shift distance property dramatically.Finally,we point out some possible directions for further studying.关键词：DNA computation;encoding problem;template method;template frame2|1102|3更新时间：2025-07-16
- 摘要：An improved fast hierarchical method (IFHM) for three-dimensional (3-D) capacitance extraction of IC Interconnects is presented.The fast hierarchical method (FHM) has been utilized for acceleration of the boundary element method (BEM) in solving the integral equations associated with the 3-D capacitance extraction problem.However,there is a shortcoming of the original FHM method: the criterion for hierarchical approximation is not explained and lack of theoretical support.The criterion plays a key role in the tradeoff between acceleration and precision.In the original FHM method the hierarchical approximation criterion was gained by a trial-and-error scheme.Here,specific and quantitative criterion is proposed in this improved FHM method.In addition,a new effective hierarchical scheme for charge evaluations is also proposed.The IFHM results in higher accuracy with about 1/3 computational time than the original FHM.Numerical examples are included to demonstrate the efficiency of this proposed IFHM.关键词：IC interconnects;fast hierarchical method;capacitance extraction;boundary element method2|1127|1更新时间：2025-07-16
- 摘要：The underwater acoustic communication scheme of long range deep-water is presented which makes use of the characters of the deep-water acoustic channel putting the communication modems at the depth corresponding to minimal sound velocity value in order to mitigate the transmission loss to improve the range of communication.The fractional Fourier transform (FRFT) is applied to synchronization acquisition and Pattern Time Delay Shift Coding scheme to mitigate the influence caused by Doppler.The results of computer simulations show that FRFT is more adaptive than copy-correlation in the Doppler shift multipath channel that will conduce to communicate with low bit-error-rate.关键词：fractional Fourier transform(FRFT);Pattern time delay shift coding scheme;long range deep-water underwater acoustic communication3|1293|10更新时间：2025-07-16
- 摘要：Sneak circuit is a latent circuit path or condition that causes undesired function to occur at some certain conditions. A step-down resonant switched capacitor (RSC) converter was used as an example to analyze the converter operating process with sneak circuit state. The sneak circuit characteristics and the sneak circuit operating conditions were derived by law of energy conservation. When sneak circuits appear,the output voltage doesn’t keep constant,but relates to converter parameters or operating conditions. The converter shows the undesired behaviors under sneak circuit state,which have been verified by experimental results.关键词：sneak circuit;resonant switched capacitor (RSC) converter;step-down2|1521|6更新时间：2025-07-16
- 摘要：This paper proposes a multilevel security model based on trustworthy state,which introduces the concept of reliability and the function of integrity measurement.It enforces diverse security rules to different kinds of objects.To prevent running intrusions,the access ranges of subjects are adjusted according to their reliabilities.The formal description of the model and the transform of its trustworthy states are given in the paper.It is proved that the system remains in a secure state after performing the security rules of the new model.Moreover,its realizing framework in operating system kernel is described,and its performance is analyzed.关键词：secure operating system;trusted computing;security model;access control2|1660|9更新时间：2025-07-16
- 摘要：A new logic method for analyzing security protocols was presented in this paper.A dynamic model was presented,which overcame the flaw of the BAN-like logic in its protocol idealization step.The basic concept of Message Unique Origin (MUO) and its determinant rules ware presented,which could be used to distinguish between "sound trust" and "unsound trust".The difference between "believe the occurrence of the event" and "believe the truth of the event" was resolved.Based on the concept of MUO,a new dynamic logic is build up,whose validity is proved by an example protocol which is soundness in the BAN-like logic but is found to have some flaws by this dynamic logic.关键词：protocol analysis;dynamic logic;BAN-like logic2|949|0更新时间：2025-07-16
- 摘要：Data streams in two sides of a two-way road endure severe unfairness problem due to the competition of holding channel resource among neighbor vehicles,which leads to very low network performance.In order to solve this problem,the relationship between the packet size and relative velocity of each way’s vehicles,and the effect of packet size on the probability of successfully competing for the wireless channel as well as the throughput of each data stream are analyzed in this paper.Based on the analysis,an adaptive packet-size adjusting scheme is proposed to improve the fairness of vehicle networks.The simulation results show that the fairness of competing for the channel has been improved greatly and the throughput of each stream is kept relatively high by this scheme.Finally,the "SRTS/SCTS" is defined and the procedure of obtaining the relative velocity is given.关键词：vehicle networks;two-way road;packet-size;adaptive2|1028|3更新时间：2025-07-16
- 摘要：Polygonal approximation of digital curve is an important curve representation method.The main problems existing in genetic algorithm based methods are the difficulty of coping with the infeasible solutions and the poor local search ability.In this paper,we propose a hybrid genetic algorithm combined with split and merge technique (SMGA) for polygonal approximation.Its main idea is that two classical methods—split and merge techniques are used to repair the infeasible solutions.In this method,an infeasible solution can not only be repaired rapidly,but also be pushed to a local optimal location in the solution space.Another advantage of SMGA is that it can solve two types of polygonal approximation problems.The experimental results demonstrate that SMGA is robust and outperforms the other genetic algorithm based methods.3|1163|2更新时间：2025-07-16
- 摘要：A new adaptive algorithm is proposed by taken advantage of SMC(Sequential Monte Carlo) which have better predictive results under the condition of nonlinear non-Gaussian.The algorithm uses particle filtering to predict an anticipated foreground district for a coming frame.Moreover,it calculates the probability of pixels to be part of background in the coming frame to guide image segmentation.It is a good method to segment image on the setting where the pixel values of foreground similar to the ones of the background by using prior knowledge.This paper uses the probability of pixels to be part of background which is calculated by the average of the predict results of particle filtering and the calculated results of prior probability model to segment image.Experimental results show that the proposed algorithm can reduce the error of the pixels of foreground to be segmented as pixels of background compared with 3 σ rule when changes in background occur quickly.关键词：SMC(Sequential Monte Carlo);prior probability;adaptive segmentation;movement detection;Gaussian model2|1581|1更新时间：2025-07-16
- 摘要：Attribute reduction theory and the Γ -reduction theory in propositional logic arose in two rather different fields.In this paper,by introducing the formal context induced by Γ ,the mutual relationship between them are investigated,then the concept lattices are built based on the formal context induced by Γ .The main purpose of this paper is to introduce the theory of Γ -reduction in two-valued propositional logic,which is the minimal set Γ 0 Γ such that D( Γ 0)=D( Γ ).Several ways to determine the Γ -reduction are studied by investigating the relationship between Γ and their subsets;an algorithm to explore the reduction by concept lattice theory is given.关键词：completely theorem;formal context;Γ-reduction;concept lattice2|1165|9更新时间：2025-07-16
- 摘要：As a basic protocol of Secure Multi-party Computation,Oblivious Transfer (OT) is of significant research and application value.Most of previous oblivious transfer protocols in classical environment rely either on public-key cryptography or on additional computational assumptions which will be very vulnerable under quantum mechanics.Based on the characteristics of Bell States,a new quantum oblivious transfer protocol is proposed in this paper.The correctness and security of the protocol are analyzed and proved.The protocol is secure in the presence of noise on the channel and a potential eavesdropper.Comparing with oblivious transfer protocols in classical computational environment,the protocol in this paper is superior in security,soundness and wire-tapping detecting.关键词：oblivious transfer;privacy amplification;bell states;unconditionally secure2|1120|1更新时间：2025-07-16
- 摘要：Opportunistic communication is receiving more and more attention as a concept that has recently revolutionized the way engineers think about wireless system design.Currently,opportunistic scheduling algorithms are studied based on many different models.Therefore,comparisons of results are sometimes difficult.This paper classifies and compares the models that have been proposed,and discuss the performance evaluation metrics,methods and results of several typical scheduling algorithms within these models.Finally,we discuss the future trends and present several topics remained to be studied in this area.关键词：wireless data network;opportunistic scheduling;QoS;fairness;stability2|1309|1更新时间：2025-07-16
- 摘要：A SPM memory allocation method were proposed based on extend control flow graph.This method transforms the application into a directed graph consisting of nodes and relationships of nodes.In succession,this method applies a refined Knapsack algorithm to solve the problem of SPM memory allocation.In the previous researches,these relationships of nodes are ignored,which result in a considerable expense of memory space during the process of SPM allocation.Our experiments show that our approach conduces to significant performance improvements (11% an average) compared to the previous.And the execution time of the application is reduced to 56% compared to none SPM environment.关键词：scratch-pad memory;memory allocation scheme;control flow graph2|1034|6更新时间：2025-07-16
- 摘要：The relationship between output voltage and capacitance in switched-capacitor DC-DC converter was investigated,and the reasons for output voltage ripple in the converter were analyzed.Aiming at the difficulties in fabricating large capacitors in the converter,a new topology of active capacitance multiplier based on OTA and CCⅡ was proposed.This circuit realized the functions of floating capacitor and grounded capacitor in switched-capacitor converter with fewer components.Taking second-order switched-capacitor DC-DC converter as an example,we simulated output performances of traditional and novel circuit structures respectively by software PSPICE.The results show that the performance of novel converter with 100pF capacitors is equivalent to the conventional converter with 200nF capacitors.And also the converter based on active capacitance multiplier has much lower output voltage ripple.关键词：switched-capacitor converter;active capacitance multiplier;output ripple;operational transconductance amplifier;Current conveyor2|2090|2更新时间：2025-07-16
- 摘要：To overcome the shortcoming of high computational cost of traditional interval optimization algorithms for high dimensional problems,an interval-genetic algorithm is presented that combines interval arithmetic and genetic algorithm.The algorithm has the advantages of simplicity and less knowledge about problems as traditional interval optimization algorithms.What is more,at each iteration the interval arithmetic provides the domains for the genetic algorithm to search,moreover,the genetic algorithm gives a direction to divide the reliable interval,and an upper bound of global optimum for a problem used to discard the intervals.Finally,a convergence is proved and numerical experiments show that the algorithm is more efficient than traditional interval optimization algorithms.关键词：genetic algorithm;interval arithmetic;global optimization2|1277|2更新时间：2025-07-16
- 摘要：A high performance 50% phase blending duty-cycle corrector(PB-DCC),designed with a purely digital phase-blending technique,is presented in this paper.The novel features of the proposed DCC include a higher reliability against process,voltage and temperature(PVT) variation due to the use of the synchronous mirror delay(SMD) technique,no-skew output clock,and much faster duty-cycle correction speed compared to conventional DCC's.When designed with a 0.13 μ m CMOS technology,the HSPICE simulation indicates that the acceptable duty-cycle of input signal ranges from 10% to 90% when the clock frequency is 400MHz and the correction operation spends only 4 clock cycles with output duty-cycle varying from 48% to 52%.关键词：duty-cycle correction;phase-blending;SMD technique;PVT;HSPICE simulation2|3014|1更新时间：2025-07-16
- 摘要：Spectral clustering has become increasingly popular in recent years.Being a pairwise method,the success of spectral clustering depends heavily on the choice of similarity measure.Through analyzing the property of data clusters,a novel data-dependent similarity measure is proposed,namely density-sensitive similarity measure,which has the ability of describing the characters of data clustering compared with the traditional Euclidian metric based similarity measure.Based on the novel similarity measure,we have a density-sensitive spectral clustering algorithm.Compared with the original spectral clustering,it has the advantages of effectively dealing with the multi-scale problems and relatively not sensitive to parameter.It obtains promising results not only on artificial datasets but also on USPS handwritten digit dataset.关键词：clustering;spectral clustering;distance metric;similarity measure;similarity matrix2|2534|46更新时间：2025-07-16
- 摘要：For the real divisible load applications,additional information and overlapped partitions are always needed.This paper introduces these factors into the divisible load scheduling model.We revised three efficient-proved schemes:equal allocation,LIFO and FIFO for the extended model,on two platforms— the master with or without communication coprocessor.Closed-form solutions for the response time of these schemes are derived.Based on these expressions,we rigorously compared the performance of the three schemes,and proved that FIFO is always the best not as without additional information,independent of the scale or type of the systems.关键词：divisible load scheduling(DLS);data parallel;scheduling2|927|0更新时间：2025-07-16
- 摘要：A model of cost estimation and control for the test automation based on the Return On Investment(ROI) model and COCOMO measurement results is presented.The maintenance cost of regression test is also taken into account.This model proposes a concept of mean maintenance cost factor and precisely predicts its threshold.We can make use of this threshold to find a suitable test mode and control its cost during the testing process in order to provide dynamic guidance and correct strategy for the whole software test automation.关键词：test automation;mean maintenance cost factor;threshold;estimation/control cost2|1225|3更新时间：2025-07-16
- 摘要：According to integration design concept of forced air convection cooling system aerodynamic design of small axial-flow 9238 fan for the CPU is implemented.File of 3D curves which are produced from Fortran procedure are imported into Pro/E to build solid modeling.The performance curve of fan prototype which is fabricated by CNC is measured in a standard wind tunnel.To reduce costs and shorten the design time,CFD is carried out to predict the performance of fan.According to outflow angle of fan series of radial heat sinks are developed.Based on the hexahedral block-grid strategy the numerical simulation is carried out on systems of fan and streamlined heat sink with Multiple Rotating Reference Frame and RNG k- ε Model.Results show that resistance of the streamlined heat sink reduces by 15.9％when compared to the traditional heat sink.The numerical simulation proves to be true by the experiment.Series of heat sinks can reach the aim of high thermal exchange effect under the direction of the integration design concept.关键词：computational fluid dynamics(CFD);entropy generation minimization(EGM);integration design;fan;streamlined-heat sink2|2072|6更新时间：2025-07-16
- 摘要：The goal of an on-line ontology-based question-answering system is to automatically derive answers from ontology knowledge bases without demanding additional information or intervention from users.This paper focuses on solving mapping task from question variable to OWL elements,which belongs to component of question understanding in question answering system.The paper presents a principled approach,which builds on tokens of question and syntax or semantic relations from NLP into set of variables and functions of constrain,and a sound optimization-based assigning mechanism to find sound substitute in OWL knowledge for question variables.A preliminary evaluation on the International WIC Institute knowledge and questions is presented.关键词：question answering system(QA);constraint;Web Ontology Language(OWL);question understanding2|1418|6更新时间：2025-07-16
- 摘要：In this paper,the throughput of a cooperative diversity communication system based on truncated ARQ protocol is studied.The theoretical throughput expressions of cooperative diversity and two-hop systems are derived.According to the expressions,throughput is affected by the MAC layer parameter data packet length L and physical layer parameter modulation level b,so cross-layer design can be used for throughput optimization.By assuming that L and b are continuous variables,the maximum throughput is evaluated by two-dimension (2-D) continuous optimization algorithms.Then a 2-D discrete optimization algorithm is proposed to find the maximum throughput,which is practical for applications.Furthermore,with the knowledge of signal-to-noise ratio (SNR) information,the 2-D algorithm is simplified into a 1-D algorithm.The 1-D discrete algorithm has only a little performance loss compared with the 2-D algorithm.关键词：cooperative diversity;truncated ARQ protocol;cross-layer design;adaptive techniques2|1315|2更新时间：2025-07-16
- 摘要：Utilizing optical microscanning technique and sub-pixel imaging processing to achieve sub-pixel imaging system is an important technical method to improve the spatial resolution of optoelectronic imaging system.By analyzing the sub-pixel imaging and microscanning reconstruction of two-dimension staring focal plane detector,the paper presents a kind of sub-pixel processing algorithm based on two-dimension microscanning and solves the margin demarcation problems.By analyzing the result of simulation,this algorithm is good for achieving sub-pixel imaging and easy to achieve real-time processing because of small processing load.The processing algorithm can be widely used in the field of visible light and infrared imaging system.Application of this processing algorithm will enormously enhance staring thermal imaging system’s performance.关键词：thermal imaging system;optical microscanning;sub-pixel imaging;image processing;margin processing2|1545|3更新时间：2025-07-16
- 摘要：Association rule mining is an important research branch of data mining,and computing frequent itemsets or frequent predicate sets is the main problem.The paper aims at mining multidimensional association rules on a relational database which includes multi-value attributes,and studies a computing method for frequent predicate sets.It presents MPG algorithm and IMPG incremental algorithm.By constructing a frequent pattern graph and applying the depth-first-search method,MPG can find all frequent predicate sets and only scans database once.In addition,the method can be expanded into IMPG algorithm which is used for incremental association rules mining by increasing once database scan at most.The paper analyzes temporal and space performance of the algorithms,and proves their effectiveness by experiments.关键词：multidimensional association rule;frequent predicate set;frequent pattern graph;incremental mining2|1107|3更新时间：2025-07-16
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