最新刊期
卷 30 ， 期 S1 ， 2002
- 摘要：This paper presents a survey of the past development and current status of software technology, along the development of fundamental computing models for software. It also analyses the main characteristics of Internet and the requirements and challenges that Internet brings to software technology.Based on this analysis,a new concept of Intemetware is presented.Internetware is a new class of software that is running on Internet and has distinct features from conventional software.Furthermore, the main research directions on Intemetware are discussed.关键词：software technology;Internet;Internetware2|3167|0更新时间：2025-07-16
- 摘要：As computer hardware and software systems become more and more complex,how to assure the correctness and reliability of such system sbecomes an urgent problem. Among theories proposed as solutions to this problem, model checking has become a very attractive and appealing approach, because of its simplicity and high level of automation. Research on model checking covers the following subjects: modal/temporal logics, model checking algorithms, efficiency of model checking with respect to time and space(especially space complexity), and development of model checking tools. These aspects are closely related. Complexities of model checking algorithms vary very much for different modal/temporal logics, and optimizations are often targeted at certain types of logic fonnulas. Some new achievements and research directions are also discussed.关键词：system reliability;modal/temporal logics;model checking2|5672|0更新时间：2025-07-16
- 摘要：With the rapid development of computer hardware and network, operating system has been developed continuously. reviewing the functions and history of operating system, this paper analyses the modem operating system,developing tendency and reason the position of it in the future.关键词：operating system;Microkernel;extensible operating system2|1543|0更新时间：2025-07-16
- 摘要：Performance evaluation is an important theoretical base and support for researches and applications of computer network and system.And it's also an important research direction in communications and computer science. This is a concise overview paper about formal methods for performance evaluation, main research results and development foreground. In this paper we focus on the three method of FM: Queuing Theory, Stochastic Petri-Net and Stochastic Process Algebra. And we primarily discuss the combinations of different formal methods. At the end of this paper we summarize formal methods for performance evaluation and open up prospects for this area.关键词：evaluation;formal methods;queuing theory;stochastic petri-net;stochastic process4|2336|0更新时间：2025-07-16
- 摘要：Feature interaction problem (FIF) is one of the most important challenges in the telecommunications. With the evolution of Internet, software (especially Web-based software) becomes more and more complex, needing more features integrated, larger scale, higher quality and more frequent evolution. As a result, FIP in software becomes inevitable and critical. It is necessary and urgent to study FIP in software in order to avoid the same problem in telecommunications. This paper introduces the fundamental concepts, achievements and trend of the FIP research in telecommunications. Moreover,tlus paper presents the status quo of the FIP research in software and our preliminary study on the FIP based on Software Architecture.关键词：feature interaction problem;telecommunications;web-based software;software architecture4|1078|0更新时间：2025-07-16
- 摘要：Network storage is a key technology in information society.The network storage technology and its application were discussed.The background of the network storage application was analyzed.The characteristic of traditional storage technology DAS was analyzed. The linutation of the DAS was illustrated. The characteristic of two leading types of the network storage technology, NAS and SAN, were discussed. The advantages of NAS and SAN compared to traditional storage technology were analyzed. The uniform trend of NAS and SAN was pointed out. Comparison of DAS, NAS and SAN was giver. Future research directions of network storage were pointed out.关键词：network storage;NAS;SAN;fibre channel;InfmiBand;iSCSI2|2422|0更新时间：2025-07-16
- 摘要：Active Queue Management maintains the smaller queuing delay and higher throughput by purposefully dropping packets at the intermediate nodes, and is becoming a focus in field of TCP end-to-end congestion control. Most of the existing AQM algorithxns follow the probability-based packet dropping mechanism originated from RED, which is disadvantage to the router performance optimization because random number generaiion needs rather computational effort.In this paper,the congestion index is put forward to quantificationally describe the network congestion state. Then, a novel intelligent packet dropping mechanism is designed based on fuzzy logic.The off line inference greatly simplifies on-line process,and thus it is very beneficial to optimize the router performance. The simulation results show that the intelligent mechanism is superior to the classical RED algorithm. It is insensitive to load variance, and able to resist against the disturbance caused by burst and short-lived http sessions, and non-elastic TJDP connections, which is very suitable for the rapidly changeful network environment.2|1298|0更新时间：2025-07-16
- 摘要：The critical challenge to component-based software reuse is the component operating platform based on middleware. The existing prevalent middleware has focused on the common problems in the development of distributed systems in almost every application domain, but ignored the commonality in a given domain. The openness and flexibility, which are the well-recognized important characteristics of next generation middleware, can enhance middleware of supporting vthe domain-orientation much more. This paper presents an open,flexible and domain-oriented component operating platform, called PKUAS.This paper describes the micro kernel intenor of the platform, interoperability framework and the meta-programming mechanism in detail. Moreover, this paper studies how to customize and extend PKUAS for the electric power systems.关键词：component;middleware;application server;domain-orientation2|1671|0更新时间：2025-07-16
- 摘要：This paper proposes a new approach to adaptively detect and to code the region of interest of scanned document, which makes use of the result of a fast segmentation algorithm based on the bi-level reduced image in order to satisfy the needs of application of the digital library. The paper Frstly describes in detail a block technique to reduce the original image, a modified smearing method to simplify computation and a fast segmentation algorithm. Based on the result of document segmentation, the paper then introduces a generating algorithm of ROI mark image and the max-shift method of document compression. Finally the paper shows an example of compressing scanned document,which includes both picture areas and text areas, by means of our scheme.关键词：segmentation;region of interest;smearing technique;document compression2|1037|0更新时间：2025-07-16
- 摘要：Time constraints are common in network protocols and are important features for real-time requirements.It is necessary to test time constraints in protocol implementations. Approaches in testing realtime are reviewed and the disadvantages are given. Some assumptions in the existing methods are revised to fit the need of our practice on testing routing protocols. We modified the theory of timed automata to convert time constraints to state variables and time events,which result in a nondetenninistic finite state machine. Abstract test suite is generated by Wp method and should be parameterized in execution. Example from RIP protocol is used to demonstrate the procedure to construct TTCN test cases.2|887|0更新时间：2025-07-16
- 摘要：Hierarchical cell structure is an effective solution to guarantee continuous coverage,to improve system capacity,and to provide better service for users with different mobility. This paper discusses CDMA(Code Division Multiple Access) system performance with Hierarchical cell structure and analyzes handover strategy with one-dimensional Markov model in micro-layer and iwo-dimensional Markov model in macro-layer. Capacity of CDMA system is related to interference level because of its self-interference characteristic. So the state space of Markov models adopted by us are unlimited. Moreover, considering priority of handover users and justice of users with different mobility,multi-level admission thresholds are set in system for different useis.The impact of the amount of reserved resource on system performance is also analyzed in this paper.2|1058|0更新时间：2025-07-16
- 摘要：Multicasting has gained much attention in recent years because it can efficiently utilize network bandwidth and reduce the load at application servers.The shared tree multicast protocol is more preferable due to its good scalability. At the same time, more and more mobile users require to participate in multicast communication. However, current shared tree multicast protocol performs poorly in dynamic/mobile environment. Some proposed protocols-one core migration protocol, improves the performance of shared tree protocol at the expense of large overhead in tree adjustment. This paper presents a new shared tree multicast protocol-dynamic multi-core protocol. This protocol can adjust the multicast tree according to the locations of multicast group membership gradually and thus provide good performance to group members with low cost. Computer simulation and mathematical analysis both show that dynamic multi-core protocol outperforms old shared tree protocol and one core migration protocol.关键词：IP Multicast;multicast protocol;dynamic multicast;mobile multicast2|862|0更新时间：2025-07-16
- 摘要：IEEE 802.11 is proposed to support delivery of radio data packets in WLA1V(Wireless LAN).The basis of 802.11 MAC(Medium Access Control) is DCF(Distributed Control Function).This paper proposes DCF+ to improve the perfonnarrce of TCP (Transport Control Protocol) over WLAN. To analyze the performance of DCF and DCF+,this paper also introduces au analytical model to compute the saturated throughput of WLAN.DCF+ is shown to be able to improve the performance of TCP over WLAN both by modeling and simulations.关键词：TCP;DCF;performance analysis2|862|0更新时间：2025-07-16
- 摘要：As a challenging problem of the upcoming next-generation networks, mufti-constrained quality-of-service routing (QoSR) is to find a feasible path satisfying multiple constraints simultaneously. For the NP complete complexity of QoSR, we propose an adjustable heuristic BFS-MCP based on converting multiple weights to a single metric with linear and non-linear energy functions. Bringing the breadth-first search with the adjustable depth to the standard Dijkstra's algorithm,BFS_MCP can adjust its computation complexity according to the CPU load on a muter in real time. Therefore, it has an extensive adaptability. Furthermore, extensive simulations show that the breadth-first search increases the performance greatly.关键词：energy function;QoS routing;adjustable heuristic;multiple constraints;performance evaluation2|1160|0更新时间：2025-07-16
- 摘要：Performance evaluation criterion is one of the most important issues for design of network traffic control mechanisms and algorithms. Due to multiple perfoxmaxrce objectives of network traffic control, performance evaluation criteria must include multiple performance metrics executed simultaneously; these are called integrated performance evaluation criteria, the research purpose of this paper. Based on the study of some basic issues such as evaluation objectives (including quality of service, quantity of service, and fair-ness), time scale, and granularity, this paper presents a set of performance evaluation criteria for the effectiveness and fairness respectively.Regarding the effectiveness,this paper puts forward a concept of Normalized Performance Function that integrates the quality of service (including the delay,loss rate,etc.)and quantity of service. Regarding the fairness, two methods are used. One is the relationship of expected value and variance of random process.Anotlrer one is the imprrovement of Raj Jain's Fairness Index.关键词：traffic control;integrated performance evaluation criteria;Quality of Service;quantity of service;fairness;normalized performance function2|1143|0更新时间：2025-07-16
- 摘要：Nowadays,many multicast QoS muting algorithms have low success ratio of muting when receivers' QoS require-menu are strict. This paper proposes a new bandwidth and delay-constrained distributed multicast muting called QDMR(QoS-based Distributed Multicast Routing).QDMR uses RBMF(Reverse Best Metzic Forwarding) instead of RPF(Reverse Path Forwarding) in seletting path to in-tree muters. Query message is forwarded if and only if it travels from a path whose reverse mute is a RBMP(Reverse Best Metric Path)from a new receiver to the current node.If RBMPs satisfy the new receivers' QoS requirements,one of them with the smallest hop counts to the multicast tree will be selected as the branch connected to the existing multicast tree. At the end, simulation shows that QDMR improves success ratio of muting reasonably and reduces protocol overheads meanwhile.关键词：distributed routing;delay constraint;bandwidth constraint;multicast routing2|908|0更新时间：2025-07-16
- 摘要：A novel and secure watermark embedding technology is given, which embeds two different watermarks into two digital images. Any information of the two watermarks from any one of the two images can not be obtained. Any information of two water-marks can not be recovered without any one of the two keys or one extracted information of two Stego-images.The validity of the technology is proved with mathematical theory, and the security of the algorithm is also discussed in the paper. The embedding algoritlun of two blind watermarks is given based on transformation domain.Then a series of attacking tests are performed with StirMark software. The test results verify that the validity of the technology.Therefore,the technology provides a new method of copyright protection.关键词：two blind digital watermark;encode;security;StirMark attack2|765|0更新时间：2025-07-16
- 摘要：A new sampling model for measurement using packet identification on IP network is provided in this paper under a principle of PSAMP,a working group of IETF,that a good sampling model should work for all purposes of measurement applications at the same time with a simple way. After researching and analyzing huge amounts of packet headers captured randomly on CERNET backbone, the result shows that 16 bits of identification field in IP packet header is enough for matching bits of sampling mask. Then a mufti-mask sampling measurement model on identification and its corrected model are provided in the paper, and the experiment also reveals that this sampling way can be used not only in traffic measurement but also for network behavior analysis.关键词：packet identification;measurement;sampling mask;bit entropy3|1258|0更新时间：2025-07-16
- 摘要：Traditional replication protocols don't take those issues into consideration such as adaptation to legacy system as well as affection to the system performance after introducing replication. Based on discussion about these protocols, a new replication protocol is addressed in this paper. Its design adopts logical token ring architecture with dynamically increasing/decreasing replicas. This paper discusses the system model and the request processing procedure of the protocol. With precondition to meet availability requirement, it not only enables adaptability to various distributed systems but also guarantees high performance of these systems. The comparison between this protocol and other typical replication protocols shows that it is feasible.关键词：replication;adaptability;availability;performance2|868|0更新时间：2025-07-16
- 摘要：The RCC theory of qualitative spatial reasoning which completely express the topology of spatial objects couldn't be directly appled to spatial query, because it can not support multi-dimension. We extend the RCC and build a spatial query oriented spatial relation model MRCC with mufti-dimensional objects supported. This model follows the common data structure of GIS, supports mufti-dimensional mereotopology relation and dimension independent union direction and distance relations. We improve the algebra of standard SQL with this spatial relation model, design and implement a mufti-dimensional qualitative spatial query language MQS-SQL.关键词：spatial query;qualitative spatial reasoning;GIS;fuzzy logic2|1258|0更新时间：2025-07-16
- 摘要：An RBAC based and policy enforcement coordination model suitable in open distributed system is described. A set of entities interacting with each other for a common glohal system task constitutes a coonlination group. In this model coordinalion is combined with access. Role based access control is introduced for security concerns and coordination policy is enforced in a distributed.The model has two characteristics of being secure and scalable.关键词：coordination;RBAC;policy;open distributed system2|854|0更新时间：2025-07-16
- 摘要：In 3D geometric modeling, objects are often represented by the triangle meshes. As to the triangle mesh model of a complex object, e. g. a human face model, a human' s organ model or an animal's model, its huge data will result in great difficulties to store, to transfer and to render. So how to simplify a triangle mesh model has become a hot topic in the research field of computer graphics world-widely. After having studied and snmmarized the presented simplification algorithms of the triangle mesh model at moment, we put forward a new simplification algorithm based on solo-envelope controlled in this paper. The conformation method of envelope presented by Cohen is improved in this algorithm. And it uses dichotomy to hang over the optimum offset value of the envelope and controls the simplification error by solo-envelope. The experimental results show that the triangle number in a mesh model is greatly,reduced and the time of running its program will become shorter when using this algorithm,so it is of higher efficiency.关键词：triangle mesh model;envelope;simplification2|1150|0更新时间：2025-07-16
- 摘要：We describe a large-scale distributed Web Crawler system, i.e.Igloo V1.2.Igloo' s distributed architecture is based on our two-tiered Hash mapping algorithm, so that it can do efficient task partition while at the same time providing dynamic scalability. As the quality of crawled Web pages is an important factor for evaluating crawlers, it employs PageRank value as die evaluation metric of pages to improve its crawling efficiency. This paper also provides a detailed discussion of the peuormance bottlenecks in crawler systems, and proposes a new URL repository access method based on "delayed merging" strategy to enable high-speed crawling.The experiments show Igloo can quickly crawl high-quality Web pages as well as present high performance.关键词：Web crawler;crawling strategy;distributed system2|1473|0更新时间：2025-07-16
- 摘要：This paper prroposes a novel semiautomatic method for semantic video object extraction. The proposed method aims at improving the semiautomatic segmentation by integrating various semantic properties of the video. Object region in the first frame is extraded by a user input polygon. Then, a tracking scheme based on backward block-marching is used to automatically extract object region in the rest of frames for general objects. Translational rigid objects and slowly changing objects are specially considered in the tracking. Finally, a mask refinement algorithm based on peer group is applied to extract accurate object boundary and insure reliaible tracking. Accurate and consistent results are obtained in the experiments by the proposed method.关键词：video object;semiautomatic segmentation;tracking;homogeneous region2|1060|0更新时间：2025-07-16
- 摘要：Multimedia and INTERNET is increasingly developing in recent years. It is crucial to develop indexing techniques for searching images and video based on their content. Dne to the lower computational complexity. compressed domain indexing lech-piques are becoming popular. In this paper, an efficient compressed image indexing scheme based on JPEG2000 framework is proposed. The target application is the access and interaction with huge amount of visual data on intemet. Here, the information on the number of zero bit-planes in code-blocks, number of coding passes in code-blocks and length of the data from code-blocks is directly extracted from the packet header of a JPEG2000 compressed image without decompressing the bitstream. A featuer vector is built based on the three-part information and is used as the image index. Preliminary experimental results show that the proposed scheme is efficient and effective.关键词：JPEG2000;content-based;image indexing;Internet retrieval2|933|0更新时间：2025-07-16
- 摘要：IP multicast is an efficient mufti-agent transport protocol. With the development of network, multicast will be morn and more important. Applications of multicast will be used in many areas..9s a fresh new thriving academic field, the main research is focused on multicast routing, the flow control, the congestion control and reliable multicast. But there are few results referred to mufticast security especially to group key management. In this paper, it will submit a scheme of group key management for large dynan vc multicast system.This scheme adopts hierarchical architectme,includes a control-center (main key management center: KMC) which is composed of a cluster of computers, and some sub key management center(SKMC) which manages its sub-domain.The scheme can efficiently handle the joining and leaving of group members and avoid one-point failure.It also enhances the robustness of the manage system.关键词：multicast;multicast security;key management;access control2|972|0更新时间：2025-07-16
- 摘要：Currently, most VPNs,based on Internet Protocol which has disadvantages in speed, expansibility and quality of service etc.Accordingly,we bring forward a solution of VPN on Multiprotocol Iabel Switching (MPIS) backbone network. We introduce Certificate Authority (CA) in this solution because both MPLS and IPSec haven't made a clear definition of authorizing identity. Taking advantages of MPLS in transporting efficiency, authorizing identity by CA, exchanging keys by Internet Key Exchange Protocol (IKE) and encrypting data by IPSec protocol, we construct a secure and efficient VPN on MPLS backbone network. Fmthemnore, we describe the realization of every component of MPIS VPN in detail.关键词：MPLS;VPN;CA;IKE;IPSec;BGP2|953|0更新时间：2025-07-16
- 摘要：IP QoS is the important bottleneck of Integrated Broad Band Network development, but the active IP QoS architecture can't satisfy the users requirements commendably. So, our research would be a new exploration about IP QoS architecture. Relying on current network condition and next generation network development demand,we researched a sort of Self-organizing IP QoS architecture based on network edge controlling and provided its routing realization algorithms.In this architecture,artificial intelligence wit control the proportion of explorer packets, chromosome packets and information packets, and provide effectively QoS for users. This orchitecture will overcome flow state keeping in the active mechanism and enhance network self-adapted and scalable through the users self-organizing behaving.This will accommodate the network development and application requirements much better.关键词：IP QoS architecture;self-organizing behaving;network edge controlling;self-adapted2|1068|0更新时间：2025-07-16
- 摘要：The quality is built in processes. The ideology of process management based on prevention has been used in software industry and induced the three basic software processes that are engineering processes, management processes and support processes.lt is the era feature of software industy that developing software and managing its quality focus on these software processes. This paper introduces the basic theory of software quality management and then a software quality management model and platform based on CMM is proposed to help software organization achieve the high level matmlty.关键词：software process;software quality management;CMM3|2195|0更新时间：2025-07-16
- 摘要：Through analyzing current ADIs, this paper points out their shortcomings and presents an XML based ADIrXBA.It applies XML to the description of software architecture,and possesses many advanced characteristics.Thrrnrgh describing the basic element that constitute architectures and making use of the extensibility of XML, XBA can describe and define the current various ADIs.关键词：software architecture;ADL;XML;component;connector2|982|0更新时间：2025-07-16
- 摘要：In complex and diversified application context, flexibility is one of the key issues of workflow technology. As an important approach to improve the flexibility of system, reflection is also available to Workflow Management System (WfMS).This paper reifies the workflow process and its management respectively from structural and behavioral aspects, and as a result, a reflective model of workflow is designed. A model of Meta-Ohject Protocol (MOP) is proposed to abstract and pmgram on meta-level, including protocol declaration,meta-object association,pmtocol selection and meta-object management.The typical instance evolution example shows that reflection is effective to impmve the flexibility and adaptability of WfMS. The implementation of reflection is presented in the paper.关键词：workflow;process;workflow management system;reflection;flexibility2|1181|0更新时间：2025-07-16
- 摘要：The elliptic curve cryptosystems over the fiute field GF(2n) receive considerable attention and are widely used because of their small key size and high security. Multiplication operation over the finite field GF(2n) is the crucial arithmetic operation. This paper presents a multiplication algorithm for the optimal normal basis type Ⅱ. The algorithm has the advantage of Massey-Omura multiplication algorithm and eliminate its deficiency.The test shows that this algorithm is simple,fast and is easy to be implemented by FPGA.关键词：finite field;normal basis;multiplication2|1023|0更新时间：2025-07-16
- 摘要：Development of object-oriented software modeling tools based on UML is discussed in this paper. The paper introduces concepts and models which object-oriented software modeling tools should suppoit, expatiates the tools' system function structure and designs, and presents a universality method for implementing object-oriented software modeling tools based on UML.关键词：object-oriented;modeling tool;model;UML2|935|0更新时间：2025-07-16
- 摘要：The practical applications of workflow management system (WFMS) demand that WFMS should support dynamic changing. To satisfy this request the designing model of traditional workflow must be improved. In this paper, a dynamic three dimensional meta-model is proposed. The meta-model is derived from the traditional laws of building model and the laws of changing. Alter re-surveying a three dimensional workflow model, which comprises process model, organization model and information model, the meta model describes the dynamic characteristics behaving in objects of process, activity, activity attributes and organization, A workflow model educed from this meta-model will possess the ability of interacting with hrunan and the ability of handling dynamic changing. The meta-model works in the way that it defines the dynamic characteristics as many as possible at the design stage and the changes in run-time can be confined in the pre-defined schema.This approach will enable WFMS to be flexible without losing the process control.关键词：worldlow;workflow management system;metes-model;flexibility;dynamic2|1235|0更新时间：2025-07-16
- 摘要：Traditional networks can only transport data passively according to the predefined protocols. With the extemiun nt network applications, new requirements are demanded on the network by end nseis. However, it is difficult to deploy new network protocols and services quckly in traditional networks. Active networking provides a novel way to solve the problems of traditional networks.Programs can be inserted into the nodes of active networks to perform customized computation.Therefore,the core functionality of active networks is to identify, transfer, load and execute active applications to perform the computation required by the end naem. This paper presents a new active application descriptor based on XML named as AADX(Active Application Descriptor based on XML), which can be used as a common method of identifying active applications and a basement for transferring and loading. It provides an effective and flexible identification and distribution mechanism of active applications in active networks.2|829|0更新时间：2025-07-16
- 摘要：This paper presents a service mobility system based on Mobile Agent: MASM (Mobile Agent Based Service Mobility) and realizes it in simulation environments. MASM takes full advantages of Mobile Agent and Java, brings forward a new design method of Mobile Agent based on "Dotting" and modularization technologies, and accordingly it reduces the network transfer load effectively and makes the realization of service mobility across different networks neatly.This paper mainy focuses on the design of both MASM system and Mobile Agent inner architecture and the implementation of concrete service mobility.关键词：Mobile Agent;Java;MASM system;mobile communication network;Service mobility2|958|0更新时间：2025-07-16
- 摘要：Accurate measurement of network bandwidth is crucial for many Internet applications and protocols. Existing band-width measurement tools such as Pathchar, Bing and Bprobe assume symmetric links. However, ADSL lines, cable modems and satellite links are popularly used, and it becomes necessary to consider asymmetric links. This paper presents a new algorithm called ALBMA (Asymmetric Link Bandwidth Measuremern Algorithm) to measure each hop's link bandwidth in both directions in an IP network, and uses the kernel density estimator algorithm to filter out measurement noise. Simulations validate ALBMA and filtering method. Compared with previous algorithms, ALBMA has alinost the same accuracy, but with higher measuring speed and lower network resource Cost.关键词：link bandwidth;network bandwidth measurement;asymmetric link;measurement noise2|926|0更新时间：2025-07-16
- 摘要：Based on LFVC(Leap Forward Virtual Clock), this paper proposes a scheme named WLFVC, which is a fully distributed wireless scheduling scheme for WLAN(Wireless LAN).This scheme is able to allocate bandwidth to streams proportional to their weights in short time scale. Besides, it takes the compensation for wireless packet collisions and wireless link error into consideration.关键词：distributed scheduling algorithm;WLAN;QoS4|927|0更新时间：2025-07-16
- 摘要：A virtual enterprise(VE)is a temporary alliance of enterprises that come together to share or core competence and resources in order to better respond to business opportunities.In order to offer their own services and to utilize the services of others in VE, it naturally demands the information sharing and interactions across organizational boundaries of enterprises. This paper presents a comprehensive methodology for building the distributed enterprises system that guarantees effectivity of coordinating and cooperating in the alliance of enterprise (i.e.virtual enterprise).It introduces the main concepts underlying virtual enterprise and virtual enterprise model(VEM). Then, it goes into details about the problem of defining a suitable VEM to effectively coordination activities in the enterprises network(ECN).关键词：virtual enterprise;enterprise agent;enterpnses cooperation network2|1228|0更新时间：2025-07-16
- 摘要：Based on the study of single pattern matching, MBF algorithm is proposed by imitating the string searching procedure of human. The algorithm preprocesses the pattern by using the idea of Quick Search algorithm and the already-matched pattern prefix and suffix information.In searching phase,the algorithm makes use of the character using frequency and the continue-skip idea.The experiment shows that MBF algorithm is more efficient than other algorithms.关键词：character using frequency;pattern matching;string2|1079|0更新时间：2025-07-16
- 摘要：Unwed Modeling Language (UNIL) has been widely used in software development. Verifying whether a UML model meets the required properties has become a challenge. Model checking is an iinportarit technology of automatic verification to ensure the correctness of designed models. Because of space explosion and complicated semantics, model checking Statecharts are restricted by the sofrware scale and the refinement degree of design.In this paper, UML Statecharts are structurally expressed by Extended Hierarchical Automaton (EHA). A set of dependence relations is specified after analyzing the characteristics such as hierarchy, concurrency and synchronization in EHA. The algorithm of slicing EHA based on the slicing cilterion which is composed by states and transitions is presented.The sliced EHA and the original Statecharts are equivalent to the property.The algorithm removes the hierarchies and concurrent states which are irrelevant with the property, and reduce the state space efficiently.2|1169|0更新时间：2025-07-16
- 摘要：Web-based application software is usually distributed,hypeimedia,autonomous and cooperative.Its life-cycle is more dynamic than traditional applications. These features impose tremendous challenges to the existing theories and methods of software development. This paper proposes an evolutionary process model called growth model for developing web-based software and discusses different possible strategies in life-cycle planning for such software.It also proposes a novel type of software environment, called software growth environment, to support the growth process. A meta-system of growth environments for testing and quality management of web-based information systems is presented,which is also being developed in growth strategy.关键词：Web-based application software;software engineering;software process models;life-cycle strategies;software environments and tools;software agents4|943|0更新时间：2025-07-16
- 摘要：Real-time middleware holds an important position in increasing distributed application development. As the basic platform, the middleware should satisty suchlike requirements: expression methodology of real-time constraints, real-time request scheduling mechanism, means of resource controlling and enabling the predictability of program lifecycle. This paper makes three contributions to the design of real-time middleware system. First, the paper defines the architecture of real-time middleware system. Second, under the analysis of distributed middleware applications, the paper presents a multi-level thread-pool real-time middleware model. Compared with traditional ones, the model has three advantages: better concurrent potential, more capability on network and resource controlling and higher system behavior predictability. Finally, the paper presents a real-time ORB under the specification of OMG realtime CORBA. Detailed experiments and comparison shows the efFciency of multi-level thread-poll real-time middle-ware model.关键词：real-time middleware;predictability;real-time CORBA2|1092|0更新时间：2025-07-16
- 摘要：In order to use the strong system verfication technology model checking in the security property analysis of network protocols, formal modeling method is still the critical problem. In this paper, a modeling method based on a high-level process descriplion language is presented According to the categorizing based on intruders'objectives and roles,we analyze the running mode of protocols from the point of view of the intruders, constructing individual process specification for each principal, then verify them using model checking tools.The analysis of the BAN-Yahalom protocol illustrates the feasibility of the approach. This approach has some generality,and provids a good reference for analysis of other network protocols.关键词：checking;BAN-Yahalom protocol;SPIN2|881|0更新时间：2025-07-16
- 摘要：A novel CAC algorithm named FBMEP(Fraction Brownian Motion Envelope Process) is proposed in this paper. It can acquire multiplex gain from both "in the source" and "across the source" by evaluating the equivalent bandwidth of self-similar traffic.On the other hand,the computation complexity of this algorithm is low.关键词：self-similar traffic;fraction Brownian motion;equivalent bandwidth;CAC2|891|0更新时间：2025-07-16
- 摘要：DCT transform and SPECK algorithm are combined in this paper. A DCT-based approach to progressive image coding is proposed,which has the characteristic of simplicity and can achieve high compression using zerotree coding method.The output stream is embedded,which is easy to control rate,and error resilient.The algorithm has low computational complexity so it is suitable for image coding and transmission with low complexity.关键词：DCT transform;wavelet transform;SPECK algorithm2|1088|0更新时间：2025-07-16
- 摘要：Reducing the characterization of systems security to characterizing the equivalence of certain processes,taking the mobility of systems into consideration, we propose a uniform framework of mobile systems security model, which is described in the setting of π-Calculus.In this framework,various noninterference security properties can be easily rephrased and evaluated,and nwe security properties can also be defined for different system requirements. Moreover, constructing a new platform for security properties analysis,this framework can be used extensively in the security analysis of mobile distributed systems, e.g.,global computing system, metacomputmg system.关键词：security model;noninterference security;π-calculus2|999|0更新时间：2025-07-16
- 摘要：This paper discusses the issues needed to be resolved when faced network-oriented RSVP is used in wireless mobile networks, and puts forward a scheme to extend existing RSVP in 3GPP2 framework-based wireless mobile networks. There are three main extensions: the first uses RSVP over IP tunnels to establish end-to-end active reservation, which will provide data flows with guaranteed QoS. The second uses mobility predication and passive reservation to make advanced reservation of wireless resource in a set of cells where mobile node will enter in the near future, and this extension can increase the probability of successfixl handoff. The third employs active handoff to reduce the time used for adjustment of reserved paths, and further improves the probability of seamless commumcatron.关键词：wireless mobile network;resource reservation;RSVP extension2|839|0更新时间：2025-07-16
- 摘要：By employing the flow-blown techniques of KE, semantic Web is targeted to provide the semantic interoperability for data and knowledge exchange.As Web is characterized by markup language, this paper extends OIL/RDFS descriptive primitives to broadly represent first-order propositional formulae, Hom Clauses and inference rules. The representation example of typical propositional rule shows the extended specification is feasible.关键词：semantic web;knowledge engineering(KE);OIL;RDF(S);hom clauses2|1246|0更新时间：2025-07-16
- 摘要：The reaserch on Internet based mobile agent technologies becomes a hot topic. Aimed at the lack of reference model in the construction of mobile agent system, this paper proposed a technical reference model, ND-MATRNI, for mobile agent environment.In this model, we present a glossary of mobile agent technology and describe the basic elements of a mobile agent environment,the functionality of each element, the relationship between these elements from the perspective of entity, service and interface. This model can be used in system construction guidance,existing systems analysis and standardization.关键词：model agent;mobile agent system;reference model2|948|0更新时间：2025-07-16
- 摘要：Formalizing UML diagrams is an effective way to get a precise UML semantics and extend the usage of formal methods.PVS is a higher-order logic based general formal specification langugae with strong expressiveness and foraml analysis tools support. By compring with other formal methods, the advantages of PVS are given in formalizing UML. A hierarchical automata model and algorithms are provided for transforming UML Statechart to PVS specification.2|928|0更新时间：2025-07-16
- 摘要：The paper gives a 2-DCT/IDCT architecture implemented by 1-DCT core according to the characteristic of MPEC-2 video encoder.The architecture's transform matrix is implemented by SRAM which has dual ports for input/output. It has the advantage of high data throughput rate and low chip area. The 1-DCT core is compared with seven multipliers which could be designed according to the computing speed.The paper gives a data arrangement scheme in order to avoid storage confusion of dual ports. What's more, a novel multiplier architecture is given by modifying constant precision which can reduce the hardware cost efficiently. The architecture is validated by FPGA which proves its engineering value.关键词：2-DCT/mCT;multiplier;FPGA validate2|935|0更新时间：2025-07-16
- 摘要：To enhance the performances of multimedia authentication based on fragile watermarking, a new fragile watermarking scheme, which exploits the perturbation of reverse problems, is proposed. To verify data integrity or authenticate signature, the new approach just solves the embedding equation instead of really extracting the embedded watermark. Because of the existence of the perturbation, the value of the reversed solution increases violendy if any tampering happened. The perturbed values not only indicate the level of the tampering, but also directly draw the shapes of the manipulated areas. Exploiting this mechanism, fragile watermarking can also use perceptually adaptive embedding, and hide watermark at every codeword of the protected data. Compared with the mostly used block-based methods, the proposed algorithm achieves the better performances of tampering sensitivity and alteration localizability, and in the meantime enhances the perceptual transparency.关键词：fragile digital watermarking;reverse problems;authentication;information hiding1|985|0更新时间：2025-07-16
- 摘要：The design of an intermediate representation is critical to compiler portability and code generation efficieucy.In order to increase the reusability of compiler components, and to simplify the development process of compilers, the paper presents an abstract intermediate representation (AIR) that provides a concise notation for describing the abstract syntax of programming language, and the inner data structures of compilers. AIR integrates algebraic data types into the object-oriented paradigm and thus makes it have stronger expressive power, flexibility, and extensibility. AIR separates the abstract descriptions from the concrete implementation. This makes it easier to be implemented in different high-level languages and thus improves the interoperatibility of compiler components. We use AIR to simulate the core of the SUIF written in C++. The result states that AIR has stronger expressive power and more compact syntax than the other languages for describing the abstract syntax of programming languages.关键词：intermediate representations;algebraic datatypes;object-orientation;compiler systems2|1180|0更新时间：2025-07-16
- 摘要：Fuzzy Cognitive Map (FCM) is applied to simulate the dynamic behaviors of the robot in complicated environments and make layout for the robot.It overcomes the defects that are not only symbolic high-level planning unfitness of a big system which has a lot of subsystems and cooperation mechanisms, but also NN and GA in which algorithms are implemented with high complexity and many training examples without cooperation mechanisms. Finally, the experimental results indicate that the robot's high level planning by FCM is more simple, robust and flexible than classical robot's planning.关键词：cognitive map;fuzzy cognitive map;robot;fuzzy causal relationship2|837|0更新时间：2025-07-16
- 摘要：Bandwidth metrics are necessary for network plan, management and performance optimization. For its merits, for example with capacity of measurement end-to-end bandwidth across several autonomous systems, a lot of algorithms on bandwidth active measurement were proposed. To compare and analyse existing methodologies is the basic for design of more precise, effective and robust bandwidth measurement algorithms. The metrics are proposed for performance evaluation of these methodologies. The lintitatiuus are discussed from principle and experimental result with bandwidth measurement experiment. Eliminating the affection of deviation accumulation and cross tragic is research direction for improving existing bandwidth measurement methodologies. An improved bmdwidth measurement method is proposed for eliminating infections of deviation accumulation caused by hop by hop measm-ement and cross traffic.关键词：bandwidth measurement;metrics for evaluation;experiment evaluation;method improvement2|1284|0更新时间：2025-07-16
- 摘要：To reduce memory size and to solve the saturation problem arising from using the associative matrix in the pattern recognition process, on the basis of analyzing the conventional system, we introduce some developments based on logical operations. The aim of these operations is to enhance the linear independence between the input patterns.By presenting examples,we can illustrate that these methods are more efficient and pragmatic.关键词：pattern recognition;neural network;associative matrix;logical operation2|891|0更新时间：2025-07-16
- 摘要：To implement sharing resources in different component libraries can improve the efficiency of finding components. Relative researches include UDM/BIDM, DCH, Uranus and UDDI. But they don't support retrieving components in existing different libraries.Classification is the base of retrieval. Faceted classification is an important scheme to classify component. This paper discusses the principle of component retrieval based on faceted classification and gives an unified facet-based method to retrieve components in multi-library,laying a foundation for sharing resources in different component libraries.关键词：software reuse;component library;faceted classification;retrieval2|1016|0更新时间：2025-07-16
- 摘要：Considering the initialization of the CMAC weight memory cells the selection of the training samples, and a quantization method of the input variable, the faster CMAC learning algorithms, variable resolution of non-overlapping receptive field is proposed, which can be conveniently realized in hardware Programming Logic Curcuit. The simulation results show that the algorithms have high convergence speed and improved accuracy.关键词：CMAC;variable resolution;non-overlapping receptive field2|822|0更新时间：2025-07-16
- 摘要：The constructed type algebra specification has been used to specify communication protocols in protocol conformance testing. In this paper, mutation analysis is inlrodaced into the constructed type algebra specification. Several kinds of mntant operators are designed and the method using mutation analysis based on constructed type algebra specification is proposed. This method provides a new probable direction for the protocol conformance testing based on the constructed type algebra specification.关键词：constructed type algebra specification;mntation analysis;mutant operator2|958|0更新时间：2025-07-16
- 摘要：This paper presents an improved muter packet forwarding model. It solves the problems of throughpout decreasing and latency increasing in the traditional packet forwarding model, and avoids the latency introduced by mutli-level queues in the traditional model. The practical test shows that the performance of the routes is improved remarkably and proves the advantages of the improved model.关键词：router;task scheduling;throughout;latency;queuing model2|822|0更新时间：2025-07-16
- 摘要：Enlightened by the knowledge of prevalent competition in evolution, a new parallel genetic algorithm is proposed which is based on multi-level compelition(GAMLC) in this paper. Experimental results show the high efficiency of GAMLC in solving premature convergence and accelerating the convergence and promoting the probability to locate the optima.关键词：genetic algorithm;multigcnup;parallel algorithm;competition2|1174|0更新时间：2025-07-16
- 摘要：Precision analysis is very important for key software to improve security, and needs to be automated because of large computing. Based on J M Voas'notional model of Fault/Failure and the PIE analysis, this paper develops a practical technology and presents an automated tool to analyze software code in detail,it describes the whole work flow of precision analytical process, especially the "automated analysis&record" phase and the notional arithmetic of three key anabses:execution,infection,propagation,and gives frame diagram of the tool. What is more, it presents the idea of adjustable granularity,which can change the precision class and analysis range, has in a way overcome the limits of Fault/Failure model and expands the possible applications. At the end, it also points out some applications such as to place assertion, estimate teliability, configure resource, design test case, and mention the elicitation to OO software testing.关键词：software testing;testability;fault propagation;key software4|1080|0更新时间：2025-07-16
- 摘要：This paper presents the value of test cases set measurement test density measurement, value of test case measurement and degree of eacecution comparability of test cases sel model based on complexity measurement. A practical measurement of the models is presented too.关键词：software test;value of test case;value of test cases set;test density;software complexity3|1459|0更新时间：2025-07-16
- 摘要：This paper presents the vector retrieval modeling using the partial match pattern for text-rich YML documents. The vector representation of the tree of text-rich XML documents and sub-documents and the tree of queries and sub-queries are decribed. The partial match pattern is mapping from the relations of ancestors and descendants for a query to the relations of ancestors and descendants for documents.The paper calculates the similarity in the processing of the partial match.The results of experiemental analyses with different collections and queries show that it is effective in the completeness search and the precision search.关键词：text-rich XML document;vector retrieval modeling;information retrieval;partial match pattern;query2|1213|0更新时间：2025-07-16
- 摘要：The current research work considered nothing explicitly about the reliability problem for the multi-user system of random degree of parallelism, such as the Web Services system (WSS).By modeling WSS as architectural random server system,this paper proposes a simulation-based approach and its implementation system, Simurel. Making use of execution profiles and failure profiles, Simurel reveals good applicability and generalization. It can be used to solve architecture-based reliability assessment in a general way, no matter single-or multi-user. The results of several experiments indicate that Simurel bears good runtime performance.关键词：Monte Carlo simulation;web services system;software reliability;simurel2|870|0更新时间：2025-07-16
- 摘要：The processing of words unlisted in dictionaries is necessary in natural language processing. Extraction of repeated string appearing in text is the most direct, convenient method, and it is rather effective. Fisting algorithms can not meet the requirement of high speed in vast text processing system. Aceording to principles of "left first" and "longest first",a fast approch named "Postitional Remembering and Jump Matching" which works in worst condition o(t2) time, where is repeating times of substring, is put forwards.Results of experments show that compared with previous methods,this method gains advantages such as high speed,simple data structures, and simultaneous scanning and matclting processing.关键词：repeated stringy extraction;automatic word extraction;Chinese text processing2|1487|0更新时间：2025-07-16
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