最新刊期
卷 34 ， 期 S1 ， 2006
- 摘要：The X-band coaxial cavity multi beam klystron(MBK) with its beam-wave interaction system and new type of pole controlled electron gun is studied.With the numerical simulation and experiment,the characteristic parameters of high mode TM310 are achieved with the appropriate impedance and stable field distribution.Using the pole controlled electron gun with double focus electrodes and its optical system,the MBK can work both in pulse and continuous pattern,and the optimized geometry parameters with high quality hollow electron beam are obtained.The non-linear calculation of beam-wave interaction is used for the X-band MBK with six electron beams and five cavities.The results show that the output peak power is about 100 kW within 30MHz bandwidth,with the interaction efficiency more than 30%,and the gain above 36dB.关键词：multi beam klystron;high mode coaxial cavity;pole controlled electron gun;hollow electron beam2|1578|0更新时间：2025-07-16
- 摘要：The geometrical and beam parameters were specified by synthetical analysis in the paper.Using MAFIA PIC code,3-D Folded Waveguide Slow Wave Structure was simulated.In the model,electromagnetic wave was introduced by waveguide mode;axial constant magnetic field was added to confine electron beam to avoid divergence caused by space charge effect.Based on interaction model,simulation results of W-band Folded Waveguide were derived,which could be the criterion of predicting and analyzing interaction circuit characteristics.关键词：folded waveguide;Slow wave structure;MAFIA;3D interaction simulations;TWT2|1429|0更新时间：2025-07-16
- 摘要：In this paper an upgraded two stage branch dividing/combining network is designed to improve the VSWR,amplitude and phase characteristic.During the design the factors that will influence the combining efficiency and the fabricating precision of the millimeter-wave band are considered synthetically,all those ensure the good combining efficiency of this network.Based on the network a millimeter-wave solid state amplifier with high performance is developed.In the band of 38-40GHz the minimum output power of the amplifier is more than 34.8dBm and the minimum gain is more than 55dB.The results show that this amplifier has good electrical performance,simple structure and is easy to be fabricated as well.关键词：millimeter-wave;power dividing/combining;MMIC;solid state power amplifier2|1366|0更新时间：2025-07-16
- 摘要：We propose a methodolo gical framework for designing security systems.This framework is founded on agent-oriented i* requirement modeling framework.We propose to use so cial modeling concepts to analyze the business and organizational context of systems with regard to security.This methodological framework encompasses analysis on the functional and non functional requirements in relevance to security,making trade off when design,thus integrating security into the system design process from the outset.This paper uses the Online Ordering example for illustration.关键词：security design;social modeling;i*framework;software engineering2|1041|0更新时间：2025-07-16
- 摘要：In today's diverse network environments,the interoperability protocols play an important role in performance of application sy stems.To assist performance assessments of application systems,we have proposed an approach to assess performance of interoperability protocols.The approach takes the real conditions of the system into account and proposes assessment criteria to make reasonable qualitative and quantitative performance analysis of interoperability protocols.In qualitative analysis,we obtain security,fault-tolerability,scalability,etc.In quantitative analysis,we build up an experimental model and a math model to obtain performance quantities such as response time,net bandwidth,and throughput.Finally,according to the criteria we have proposed,we produce the result of performance assessment of interoperability protocols.关键词：performance;interoperability;assessment;experimental model;math model;qualitative analysis;quantitative analysis;queuing theory2|1138|0更新时间：2025-07-16
- 摘要：An enhanced BPEL supporting system is proposed based on our previo us work to facilitate the dynamic adaptation of composite services,which is often desirable and sometimes unavoidable to keep the services facing evolving environment and varying user requirements satisfactory.With this approach the runtime architecture object which describes the architecture of a comp site service is utilized to further decouple the composite service from its constituents by redefining the service references under the current architectural context.The dynamic adaptation is implemented by reinterpreting communicating behaviors between the composite service and its constituents,which is naturally resulted from the modification of the runtime architecture object.A simple application is also developed with the supporting system to illustrate the effect of this architecture based dynamic adaptation mechanism.关键词：service-oriented computing;services composition;BPEL;software architecture;dynamic evolution2|979|0更新时间：2025-07-16
- 摘要：In order to deal with the complexity of large sy stems,the divide and conquer policy is adopted in requirements engineering:collect requirements from different groups of stakeholders,and then compose them together as a complete requirements specification.However,the policy brings forward the problem of overlapping use cases:similar event flows appear in more than one use case.Duplicate event flows lower the readability and maintainability of use case diagrams.The problem has been recognized,but no detecting approach is available to find out duplicate event flows.The paper propo ses a heuristic algorithm which is based on information retrieval technologies.Evaluation results suggest that the algorithm is efficient and effective.2|901|0更新时间：2025-07-16
- 摘要：Human understanding and control of complex systems development often seem unattainable goals.The problem is substantial for future construction of network-centric,large-scale software systems.Evidence suggests that software engineering is reaching complexity and scalability limits of technologies.Software development and software quality is troubled with software complexity.New and emerging research efforts on complex networks introduce a new mathematical foundation for software complexity metrics.This paper discusses the forming mechanism and metrics methods of software complexity,and introduces recent progresses about associating software complexity with complex networks.Based on software complex networks,some methods of software structure complexity metrics are proposed.Focusing on combination of complex networks model and evolutionary algorithm,a model for software evolutionary complexity metrics is presented.关键词：software complexity;complex networks;complexity Metrics;next2generation software engineering(NGSE)2|3308|0更新时间：2025-07-16
- 摘要：The building of application layer multicast tree is a NP-complete problem.Today there are several heuristic ALM tree building algorithms.But all the algorithms have some restrictions because of their considering conditions.Making good use of the ALM tree resource,it selects its parent by comparing network link states to build the ALM tree.Considering of the highest network bandwidth、degree-constrained、enough living time,we present an algorithm based on Optimizing resource usage for building ALM tree to get a big throughput.This algorithm is shown to be more stable and more balanced for building the ALM tree by simulation of the mathematical model comparing to other ALM tree building algorithms.关键词：application-layer multicast;enough living time;link delay2|1061|0更新时间：2025-07-16
- 摘要：It was not sufficient to predict the software fault based on partial phases of software development process or some metrics by analyzing the current fault predicting methods.This paper proposed to build a fault predicting model based on BBNs (Bayesian Belief Networks) by using the information of software development process.Based on a simple BBNs fault prediction model,a general fault prediction model was proposed by expanding the basic node.We brought forward that the software metrics and experts' knowledge could be used to determine the node status probability distribution.The simulation experiment proved that this model with good fault predicting ability coincided with the real case.关键词：software fault prediction;bayesian belief networks;software metrics2|1633|0更新时间：2025-07-16
- 摘要：The fault coverages achieved by the test generation procedures based on genetic algorithms are smaller than the deterministic test generation procedures for combinational circuits.One of the possible causes for this deficiency is the high,long-distance schema,which exists in the process of automatic test pattern generation.Thus genetic algorithms in dealing with such problems easily fall into local optima or premature convergence.In this work,we firstly propose the test generation procedures based on estimation of distribution algorithms.Estimation of distribution algorithms are able to capture the interrelations between the primary inputs by joint probability distribution.And therefore obviate the influence of the high,long-distance schema;alleviate the problem of premature convergence.The experimental results for benchmark circuits prove that the proposed procedure can achieve higher fault coverage.关键词：estimation of distribution algorithms;automatic test pattern generation;combinational circuits2|1109|0更新时间：2025-07-16
- 摘要：This paper presents an algorithm that can automatically detect and extract text in digital document images.Firstly,we process and fuse Gabor filtered images at different orientations and scales and obtain an image that reflects the layout of the document image.Then,potential text regions are directly extracted from the resulting image.Finally,two criteria based on the geometrical property and high frequency content are adopted to kick-out those non-text regions.The experiments are performed on some representative images with different styles and with texts in different languages and fonts.Experimental results show that the algorithm works well on document images from a wide variety of source.关键词：text extraction;Gabor filter;digital document images2|1614|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 novel multi-scale incremental predictor is proposed.This predictor decomposes the complex time series into a series of intrinsic mode functions(IMF) and a residual signal with empirical mode decompo sition firstly,and then an Incremental Independent Vector Combination Predicting algorithm in Kernel Space(ⅡVCPKS) is constructed for predicting every IMF or residual signal.The propo sed predictor is competent for predicting the complex time series in real time.Experimental results showed that the propo sed method performed very well in the task of predicting complex time series.关键词：complex time series;predicting;empirical mode decomposition(EMD)4|1962|0更新时间：2025-07-16
- 摘要：In SVM algorithm,when training sets with uneven class sizes are used,the prediction result of classifier is undesirably biased towards the class with more samples in the training set.That is to say,the larger the sample size,the smaller the classification error,whereas the smaller the sample size,the larger the classification error.Aiming at this orientation problem and with the analysis of the cause of it,an improved method based on genetic crossover operator was proposed,for the training set with small size generate new samples by using crossover operation,thereby compensates for the unfavorable impact caused by the bias of the training data class size.Simulation experiment results on UCI stander data shows that the proposed method has better classification accurate compared with stander support vector machine method.关键词：support vector machine(SVM);crossover operator;uneven class size;pattern recognition2|2323|0更新时间：2025-07-16
- 摘要：A novel microstrip-fed folded planar monopole handset antenna is proposed.The effect of the structural parameters on the impedance and radiation characteristics of the antenna is analyzed by using FD TD method.The results of FD TD are essentially agreement with experimental results.The proposed antenna has properties of simple structure,broad-band,easier to feed,and easier to integrate.This novel folded planar monopole handset antenna provides a new choice for the third generation mobile communication system.关键词：planar monopole antenna;FD TD;mobile antenna;3G7|1115|0更新时间：2025-07-16
- 摘要：The differential evolution algorithm is robust,easy to use,requires few control parameters,and has various optimization strategies.Based on analysis of advantages and disadvantages of these optimization strategies,a modified differential evolution algorithm with hybrid optimization strategy is proposed.The main idea of the modified differential evolution algorithm is to divide all of the individuals into two groups randomly,and the two groups adopt different optimization strategies.The convergence speed and search succeed probability of the modified differential evolution are tested using five benchmark functions for optimization algorithm,and the results are compared with dynamic differential evolution and particle swarm optimization.From the simulation results,it is observed that the search efficiency of the modified differential evolution is significantly improved as well as the high search succeed probability is ensured.关键词：optimization algorithm;optimization strategy;differential evolution algorithm2|1399|0更新时间：2025-07-16
- 摘要：The efficient motion estimation algorithms are the important research hotspot in the real time-video coding-decoding technology.The prediction error can be decreased by incorporating high accuracy estimation and compensation,and the performance of compressed video can be improved.The high computational demands of the H.264 video encoder are reduced by an deformable block-matching algorithm using the node-based model.This algorithm well exploits the motion vector statistic characteristic and correlation and uses motion estimation criterion based on the pixel difference classify.Experiments show that the efficient motion estimation algorithm proposed can further reduce block matching distortion computations relative to conventional fast motion estimation algorithms with neglectable coding efficiency loss.关键词：video coding;motion estimation;block-matching;matching criterion2|1087|0更新时间：2025-07-16
- 摘要：The compatibility of the stepped frequency mode and pulse Doppler mode has been studied based on the conical scanning system.The signal selection between stepped frequency and pulse Doppler was analyzed in theory.The arithmetic and the application of the conversion between the two systems were discussed.Outside test was validated about high rang resolution and angle measure of MMW seeker under the compo site system of stepped frequency and pulse Doppler.The result shows that the high rang resolution and angle detect for rest and move target is feasible based on the compo site system of stepped frequency and pulse Doppler.关键词：stepped frequency;pulse Doppler;conical scanning2|1014|0更新时间：2025-07-16
- 摘要：When the local competition based selection is adopted in the genetic algorithm,the algorithm is difficult to escape from the local optimum.In this paper,a selection operator based on the difference among individuals is proposed.Competition occurs within an area defined by the difference,which helps to maintain the population's diversity and enhance the ability to escape from the local optimum.The experiments show that,the genetic algorithm adopting the improved selection operator can effectively ensure the success and effectiveness of the optimization,even when there is severe vibration around the global optimum.关键词：genetic algorithm;selection operator;local competition2|1493|0更新时间：2025-07-16
- 摘要：For airborne bistatic SAR system,bistatic SAR uses separated transmitter and receiver flying on different platforms,the difference between the oscillator clock of receiver and transmitter will result in phase drifts error,which will accumulate during the whole imaging time.The paper will concentrate on the problem of frequency synchronization between a bistatic transmitter and receiver pair,firstly a possible solutions(GPS+high stable local oscillators) for synchronization error compensation is given,and the corresponding phase error aroused by the abo ve frequency synchronization method is analyzed,then a synchronization error compensation method based on the direct communications between the transmitter and receiver pair is studied in detail.At last,this paper shows the simulation of frequency synchronization error compensation of several representative frequency synchronization error models,which shows the validity of the compensation method in the paper.关键词：bistatic synthetic aperture radar;frequency synchronization;frequency synchronization error compensation2|943|0更新时间：2025-07-16
- 摘要：The main problems in the field of information steganography are indicated.In order to solve these problems,the ideas of comprehensive information theory and the methods of fuzzy information processing are introduced.Upon these,the information space is proposed and classified in three aspects.In the information space,the research of steganography and steganalysis can be done accordingly.The framework of steganalysis is then propo sed.关键词：steganography;steganalysis;comprehensive information theory;fuzzy information processing2|1559|0更新时间：2025-07-16
- 摘要：Now people are concerned about that how to protect the digital media copyright more and more.And for relational data,that how to protect its ownership and not to affect its usage becomes a difficult problem.A reversible watermarking scheme for relational databases on numerical attribute is proposed.The basic idea of the scheme is to embed the watermark information into relational databases with exclusive or under some secret parameter,and the original data can be recovered losslessly from the unmodified watermarked relational databases with exclusive or under the same secret parameter.Only the person who owns the private key and other unique parameters can recover them perfectly.Through the algorithms and some experiments analysis,the scheme is proved to be invisible and feasible.关键词：reversible watermark;digital watermark;relational databases2|1439|0更新时间：2025-07-16
- 摘要：A new image steganography mothod simulating quantization processing in image Joint Photographic Experts Group compression is presented.Three kinds of error correctiong coding is applied to assure that hidden information can be retrieved accurately.Experimental results demonstrate that the proposed method has high capacity good vision performance.关键词：steganography;vision redundance;hidden capacity;space domain;frequency domain2|1048|0更新时间：2025-07-16
- 摘要：Joonsang Baek et al.proposed a new type of universal designated verifier signature(UDVS) which is called universal designated verifier signature proof(UDVSP).We present an efficient UDVSP scheme based on Zhang Safavi Susilo(Z SS) signature scheme.Using the properties and pre computing of the bilinear pairings,our proposed scheme only needs two parings computations.Furthermore the scheme uses general cryptographic hash function,and does not require special hash function(Map to Point).The security of our UDVSP scheme is then proven in the random oracle model.关键词：universal designated verifier signature;hash function;random oracle;bilinear pairing2|1058|0更新时间：2025-07-16
- 摘要：A novel gray-level digital watermarking is proposed.It uses grayscale image instead of binary image as the watermark.The watermark image is decomposed using two layer wavelet transformation and a simple quantization technique is used to further decompose the coefficients into bit sequences.After original image is decomposed using three layer wavelet transformation,the lattice vector quantization is used to construct the embedding strategy,in which coarse and detail watermark sequences are embedded into coarse and detail coefficients of original image,and the extracting strategy without need original image.To enhance security of the watermark,chaotic sequence is used to modulate the watermark.Experiment results have demonstrated that the proposed algorithm is more robust against J PEG compression and additive white gaussian noise than other similar watermarking algorithm,while the watermarked images have better quality.The recovered watermark image has good quality even under J PEG compression with a quality factor of 30.关键词：grayscale watermark;wavelet;chaotic sequence;lattice vector quantization;D4 lattice2|1147|0更新时间：2025-07-16
- 摘要：The extraction and fusion of statistical features has been a key problem demanding solving for steganalytic technology in the context of the prisoner's problem presented by Simmons and Cachin's security theory model.We divide the statistical features into two categories,i.e.,inherited features and introduced features,and the importance of these features is further discussed.Furthermore,based on the research of steganalytic methodology and the theory of holism,a fusion strategy of statistical features is proposed,and the availability of the proposed fusion strategy is verified by our image steganalysis system,which is developed using the strategy.关键词：steganalysis;inherent feature;introduced feature;holism;feature extraction;feature fusion2|1120|0更新时间：2025-07-16
- 摘要：We present a "virtual node" simple graph representation for full-2 code(corresponds to complete graph),this rep resentation simplifies the double erasure correcting data layout judgment theorem,the optimal redundancy data layo ut theorem and the construction of B-CODE.We also present a data layout construction method based on P1F of complete bipartite graph(corre sponds to 2d parity code),this method can produce highly extensible double erasure correcting data layouts(BG-HEDP).Compared with other data layouts,such as B-CODE,BG-HEDP also has optimal update penalty,high reliability and low encoding/decoding complexity,its redundancy is very close to optimal value,while it is superior in extensibility to others.关键词：RAID(Redundant Array of Independent Disks);2-erasure-codes;data layout;complete bipartite graph;perfect 1-factorization2|755|0更新时间：2025-07-16
- 摘要：Digital image forensics aims to distinguish the forgeries from the authentic images.In order to detect blurring,which can reveal the trace of tampering,we analyze the local color correlation and consistency caused by image acquisition devices.We find that blurring can distort the intrinsic local color correlation and consistency of legitimate images.Therefore,we define the abnormity of local color property as rate of abnormal hue,of which we then develop a forensics method to detect blurring.Experimental results show that this method can detect possible blurring in images acquired from digital cameras and locate the possible tampering regions with a relative high accurate rate in detection and location.关键词：image forensics;blur;color property;rate of abnormal hue2|2431|0更新时间：2025-07-16
- 摘要：The human immune system has many features for inspirations to information security.We design a framework model using an analogy of human immune mechanism.This model can be used to provide the protection for the safety of important information.The suggested framework consists of two parallel information transmit networks:conventional transmit network(CTN) and immune lympho id transmit network(ILTN).conventional transmit network provides the end to end services and transmits important information from one end point to another.Immune lymph transmit network provides authentication and control services that monitor and manage the activities of conventional transmit network.We also discuss a solution to the security of the mobile agent.This paper also accomplished corresponding experiments.The results of the experiment showed that the use of this model is very efficient for the problem of discrimination of the self and non-self.关键词：immune system;information security;mobile agents2|1029|0更新时间：2025-07-16
- 摘要：This paper presents a model named DCCM(Distributed Cooperation Conflicts Model) for conflicts avoiding,detecting and solving for 3-D distributed CAD cooperative design.DCCM classified semantic CAD operations into two types,mixed operation serialization and semi optimize lo cking for concurrency control,afforded cooperative awareness to avoid conflicts,used 2-level conflict solving system,detected conflicts based on operation's semantics,afforded interceder based consulting policy for conflicts solving.关键词：computer supported collaborative design;computer aided design;conflict;concurrency control2|1314|0更新时间：2025-07-16
- 摘要：The idea of a connector,which explicitly describes the interactions among components,is one of the important contributions of the research on software architecture.In this paper,we argue that such an important abstraction deserves first-class support from programming languages.We proposed a new component-oriented programming language SAJ(Software Architecture-based Java),which integrates some ar chitectural concepts such as the component,the port and particularly the connector into SAJ.The connector is treated as a first-class entity in SAJ as is the component so that software architecture can be made more explicit at implementation level and the simultaneous reuse of the component and the connector can be realized.We formalize our language giving both the type system and operational semantics and show its soundness property.关键词：software architecture;connector;Type system2|918|0更新时间：2025-07-16
- 摘要：Based on the study on Web-based systems,this paper presents a systematic testing framework for Web based systems.And focused on test modeling of business logic layers of Web based sy stems,a EJB test model,one kind of platform specific test models(PSTM) according to model driven testing(MDT),is defined,as well as the approach of its model recovery and model checking are provided.The test modeling deals with the static structures and dynamic behaviors of EJB from the component level and describes a mechanism of code failure detection based on its model checking,which will provide a good support for test cases and test data generation.关键词：enterprise JavaBean(EJB);component testing;test modeling;model driven testing(MDT);platform specific testmModel(PSTM);component identification;model recovery;model checking2|939|0更新时间：2025-07-16
- 摘要：Functional semantics of a component is an important factor for the reuser to understand and judge the reusability.So it is important to give the representation of components on the same knowledge base of component developers and reusers.Now there have been some appro aches,which introduce ontology as the base of semantic representation for components.However,they have some shortages in precision and support for semantics reasoning when composition.A meta-model of domain ontology supporting semantic representation of components is presented.Based on the meta-model port semantics,static semantics and semantic protocol of components and the semantics composition algorithm are given.Then semantics of components can be composed along with component composition according to the static semantics and the algorithm.It can help developers to perform the semanticsbased adaptation and composition analysis of components.2|1028|0更新时间：2025-07-16
- 摘要：Aiming at the segmentation of pulmonary nodules on multi slice CT images,the paper put forwards an interactive manual method for nodule segmentation.It replaces Laplacian in Live Wire algor ithm with Canny operator,which addresses the problem of false and disconnected edge when using Laplacian for edge detection.Experiment shows that this method enables doctors a faster segmentation of nodules in ROI,which is prerequisite to quantitative analysis and 3D reconstruction.From the result of segmentation and 3D visualization,segmentation by using this method has turning out to be ideal.关键词：detection of nodules;lung image;segmentation of image;Live wire algorithm2|1092|0更新时间：2025-07-16
- 摘要：The method of dynamic voltage scaling(DVS) is an efficient technology for saving energy.This paper put forwards a near optimal strategy on multi core processor using DVS.It changes the problem of voltage scaling to the problem of slack time allocation.It detects the slack time based on task structure firstly.Aiming at different kinds of slack times,it then uses relevant allocating method such as parallel compensate algorithm.Result of the experiment indicates that the strategy of this paper can decrease the energy consumption efficiently and has low complexity.关键词：DVS;real time task scheduling;chip multi processor2|1586|0更新时间：2025-07-16
- 摘要：In WSN(Wireless Ad-hoc Sensor Network),some sensor nodes could die with their limited power consuming,which leads to the decrease of the point covering quality.Thus a method must be found to evaluate the quality of nodes' covering.An evaluating algorithm is proposed to measure how well a set of object points are monitored by sensor networks on the basis of Monte Carlo algorithm.The algorithm evaluates some points which are randomly selected from the set of object points.If all selected points meet the requirement,it will return;or it demarcate those object points which don't meet requirements.Repeat to call the algorithm limited times,which will make the ratios of the correctness of the quality evaluation algorithm exceed 99%.So it solves point covering problem effectively in WSN.The simulation shows that it is feasible.关键词：wireless sensor network;point covering;Monte Carlo algorithm2|1156|0更新时间：2025-07-16
- 摘要：The openness of Internet offers great convenience of information sharing and exchange,accompanied with crucial challenges to Information Security.As a kind of active measure of Information Assurance,Intrusion Detection acts as the effective complement to traditional protection techniques.On the base of analyzing KMP algorithm & BM algorithm,which are fashionable pattern matching algorithms in intrusion detection system at present,the author gives an new pattern matching algorithm in place of the BM algorithm.The results show that the improved pattern matching algorithm has better efficiency and is helpful to reduce systematical missing package rate.关键词：KMP algorithm;BM algorithm;intrusion detection2|1240|0更新时间：2025-07-16
- 摘要：As the main weapon of worship end defense,small bore shipborne gun's characteristics of real time,speediness and precision are very important.In allusion to the difficulty of the traditional closed loop fire correction in miss distance quantity measuring,a new method of fire correction against air is presented.This method observes the object's actual movement first,and then calculates a series of ordinal and contrary fire data.Based on these fire data,fire data error sequence can be gained,and consequently fire data error correction can also be forecasted.The method presented called virtual closed loop fire correction,is demon strated to be practicable by digital simulation and the result of experimentation.关键词：virtual fire correction;closed loop fire correction;air defense;anti missile2|1204|0更新时间：2025-07-16
- 摘要：A new method for predicting the one dimension radial distribution of chaff clouds was proposed and the modeling approach was given in detail.The experimental results demonstrate the validity of this new method.关键词：chaff clouds;inverse scattering;support vector regression2|1124|0更新时间：2025-07-16
- 摘要：Use-case driven developmentaims at reducing software complexity through use case that starts with the actor.However,some tangling and scattering concerns in different use cases look tricky because of the deficiency of object-oriented technique.It makes software more complex.This paper presents a use-case driven extension approach-UCD/Theme approach,which uses aspect-oriented technique to facilitate separation of concerns on requirement analysis phase.Finally an ATM case study is given to illustrate the feasibility of the method.关键词：aspect-orientation;theme;use-case driven;separation of concerns2|1277|0更新时间：2025-07-16
- 摘要：This paper aims at establishing a capability measurement index system through an analysis of the Chinese IT industry innovation mechanism.Five capabilities are measured and calculated,namely,technology innovation,industry chain innovation,industry focus innovation,application innovation and policy innovation.Based on these measurements,this paper further expounds on the direction and focus of Chinese IT industry development with the aim of improving innovation capability.关键词：IT industry;innovation;capacity;measurements10|1690|0更新时间：2025-07-16
- 摘要：The relativistic backward wave oscillator(RBWO) based on superradiance(SR) mechanism is becoming a new technical scheme of compact high power microwave system owing to its generation of nanosecond or subnano second pulse with high peak power,high peak conversion efficiency and fast leading edge.The recent experimental development of SRRBWO in Russian was briefly introduced.The latest development in Ka-band and X-band was reported in detail,and the developing trend and some key technical problems were presented.关键词：superradiance;relativistic backward wave oscillator;high power microwave2|876|0更新时间：2025-07-16
- 摘要：The development for Internet of Things was described.A feasible scheme was shown for China Internet of Things and its information services system(RFID-IS) was proposed.In order to manage the net efficiently,the managing protocol(RFID-MP) was studied based on advantages of SNMP(Simple Network Management Protocol).The research contributes to the design,information service and network management development of China Internet of Things.关键词：RFID;Internet of Things;RFID-IS;RFID-MP3|3555|0更新时间：2025-07-16
- 摘要：Semiconductor wafer fabrication is a class of typical re-entrant complicated manufacturing system,which has important characteristics such as re-entrant process flows,complexity,uncertainty,multi objective and multi-constrain.Nowadays,optimized scheduling problem for wafer fabrication is an important research branch in the control.In this paper,the research progress of modeling methods and scheduling strategies for semiconductor wafer fabrication are systemically reviewed according to the main research achievements in recent years,and their primary virtues and deficiencies are also analyzed and discussed,furthermore,their applicable cope are also presented.On the other hand,the criterions and methods of rescheduling are briefly generalized.Some problems worthy of further study and probably developing trends in the semiconductor manufacturing field are presented.关键词：semiconductor wafer fabrication;modeling;scheduling;rescheduling2|2102|0更新时间：2025-07-16
- 摘要：Validity and stability of information passed between receiver and transmitter are affected directly by the intensity and uniformity of magnetic field transmitted by electromagnetic induction devices in adjacent movement.Based on the electromagnetic induction fuze setting system in artillery and according to electromagnetic filed theory,theoretical analysis and numerical simulation is completed for the uniformity of magnetic field distribution in axial direction for current carrying solenoid of finite length.An optimal structure is proposed for fixed radial and axial size,and the results are verified by experiments.Experimental data is in good agreement with theoretical analy sis,which shows that the design is correct.Methods of design and experiment can be applied widely to other electromagnetic induction sets.关键词：electromagnetic induction devices;magnetic field distribution;uniformity;numerical simulation;structure optimization3|1203|0更新时间：2025-07-16
- 摘要：To resolve the problem of low locating rate in fault diagnosis of air borne radio equipment,the idea was proposed to using preceding fault information in the tests of batch equipments.By studying the failure rules of batch equipments,the fault probability under extreme-small-sample conditions was estimated using Bayesian theory.Four methods were adopted to direct fault detecting.The simulation results showed that the strategy of this paper could improve the rate of locating faults correctly in one time detecting progress and reduce the fault searching time,and can enhance the efficiency of fault diagnosis.关键词：Bayesian estimations;tests of batch equipments;fault diagnosis;air borne equipment2|1147|0更新时间：2025-07-16
- 摘要：The testing for mo oring and sea trials of ship electronic equipment still depends on men to record data from multiequipment,analyze errors,and output report forms afterwards.The problems existing for testing are inefficient,low precision,and not real-time.By studying whole life real time testing technology based on LXI(LAN eXtensions for Instrumentation) bus for electronic equipment on warship,such as computer net interfacing and data filtering,dynamic data monitoring and recording,data visually analy zing,report forms printing,the problems mentioned above can be solved.关键词：electronic equipment experimentation;automatic testing technology;ship2|913|0更新时间：2025-07-16
- 摘要：We present a technical architecture for user preference model,and show the nature of the problem represented within a Markov Decision Process combined with adaptive reinforcement learning algorithm.We provide a possible candidate solution for user modeling dynamically to satisfy the users expected preference based on minimal or missing information,it is also a exploration for the evaluation of the user experience when selecting service providers.Simulations of the representative user models show that the adaptive reinforcement learning solutions are effective.关键词：utility theory;user preference;Markov decision process;reinforcement learning2|1140|0更新时间：2025-07-16
- 摘要：Basing on the simulation of magnetron injection gun,cavities and interaction between electron beam and wave,the design and experiment of 8mm four cavity gyroklytron are reported.Initial experiments show an efficiency of 23.4%,a 3dB bandwidth of 280MHz,and a saturated gain of 31.9dB which corresponds to peak power of 172kW and average power of 2kW.关键词：8mm;gyroklystron;simulation design2|1041|0更新时间：2025-07-16
- 摘要：In this paper,a high-order symplectic finite difference time domain schemes is constructed for Hamilton system,a three-dimensional fifth-stage forth-order formula of iterative algorithm is proposed.The Return loss and Input impedance of microstrip antenna be calculated using Symplectic finite difference time domain method(SFDTD) and absorbing boundary condition.Calculating results have shown that the SFDTD method is accurate and effective.关键词：microstrip patch antennas;SFDTD;hight order method;Numerical analysis2|921|0更新时间：2025-07-16
- 摘要：On the base of analyzing how to develop file enc/decryption system based on VFS of Solaris with the technology of redirection of system call and how to make it work with OS seamlessly,the author make progress on the simple model of file enc/decryption system and gives the improved model of file enc/decryption system.The result shows that the improved model has better efficiency and reduces the impact to the OS on performance effectively.关键词：redirection of system call;file enc/decryption;virtual file system(VFS)2|1024|0更新时间：2025-07-16
- 摘要：Markov Logic Networks(MLN) is an important model in Statistical Relational Learning.Nowadays deterministic search methods are the main methods to learn MLNs.However,the result was not compact and the algorithms can easily get into the local optima.Aiming at solving these problems,we defined the predicate template and the clause template to reduce search space and put forward a learning algorithm using Genetic Algorithm(GA),which code is clause template,to learn MLNs's structure,using Particle Swarm Optimization(PSO) to learn MLN's weight.We gave the fitness function which makes the algorithm convergence,design the genetic operators.We testify our algorithm can get better result by theoretical analysis and experiment comparison.关键词：statistical relational learning;markov logic networks;predicate template;clause template;genetic algorithm;particle swarm optimization2|964|0更新时间：2025-07-16
- 摘要：This paper propose a quantitative information security risk metric based on information system security analysis,gap analysis method and its assessment procedure.Through security gap analysis method,we can compute quantitatively the difference between security target and TOE security in security assurance control and security assurance capability,and then improve the information system security architecture design and its assurance level.Using the metric,we can also compare the benefit difference among security contols,and calculate the input-output analysis.This computable information security risk assessment metric and method was applied in real case and proved effective.关键词：gap analysis;security assessment;risk assessment;security metric2|1375|0更新时间：2025-07-16
- 摘要：A single load microcalorimeter with auto-feedback is constructed as the national coaxial primary standard for broadband power of China.A temperature-compensated coaxial themistor mount is used as working standard inside.The effective efficiency of the working standard is calibrated from the RF power loss in the mount which is measured by a calorimetric method.The part of RF power loss in the mount wall is measured with the temperature-compensation themistor in the mount instead of traditional thermal coupler method.The new method has advantages of short response time,high sensitivity and simple structure.Implement method and uncertainty analysis of the power standard is presented in detail.International comparison data and figures are also included for confirmation of the power standard accuracy.关键词：metrology;power measurement;power standard;micro calorimeter2|1108|0更新时间：2025-07-16
- 摘要：Feature extraction is a vital part of watermarking technology that resists geometrically attacks.The points extracted from the image will directly influence the robustness of the watermak exists in the image.This paper improves Harris-Laplace corner detector by presenting a novel method to extract geometrically invariant feature points based on the scale space theory.According to the experiments,the proposed method can select those feature points that resist several geometrically attacks such as scaling and cropping,but at the cost of lower computation.关键词：feature points extraction;Harris corner detector;scale space theory2|2140|0更新时间：2025-07-16
- 摘要：This paper proposes an identity-based(ID-based) partial delegation proxy multi2signature scheme with warrant based on bilinear pairings on elliptic curve.The scheme has strong non-forgeability,strong non2deniability,strong identifiability and prevention of misuse.关键词：proxy signature;proxy multi-signature;bilinear pairings;ID-based cryptography2|1020|0更新时间：2025-07-16
- 摘要：Most existing trust management systems have two main problems,(1) hard to provide security guarantee for web resources since their implements do not comply with Web Service standards;(2) the chief trust engine runs at a low efficiency,cannot fulfill demands of on time security policy in the all long changeable environment.We use java language to design and implement a trust engine oriented to Web Service based on mobile agent to satisfy security demands in the open and dynamic web environment.The main work of trust engine is to verify whether a web resource can be visited by some client.We use mobile agent to do bidirectional trust chain discovery to impro ve the efficiency of the trust engine.关键词：Web service;trust manager;trust engine;trust chain;credential;mobile agent59|8246|0更新时间：2025-07-16
- 摘要：Multimedia applications are computation intensive,with kernels accounting for the majority of all dynamic execution time.Thus,research of multimedia applications mainly focuses on the code kernels.In this paper,kernel of inner loop in multimedia applications is analyzed,with its inherent parallelism-subword parallelism.And a bitwise dataflow analysis method is presented for inner-loop identification.关键词：multimedia;subword parallelism;inner-loop;dataflow2|984|0更新时间：2025-07-16
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