A method for modeling crosscutting concerns in the concurrent software system is presented based on the aspect-oriented（A-O） technique and the statechart of unified modeling language （UML）. Modeled with UML statec...A method for modeling crosscutting concerns in the concurrent software system is presented based on the aspect-oriented（A-O） technique and the statechart of unified modeling language （UML）. Modeled with UML statechart diagrams, the primary system functions and corresponding traversal features are enveloped into various orthogonal regions of a composite state. The mutual relationships between orthogonal regions are implied by the orders of broadcast events. Using a modular transition system as a basic computational model, the formalization description of A-O statechart models is proposed. The precise semantics of model elements and modeling procedures is given. The example study indicates that the separation strategy of crosscutting concerns is implemented in the design phase of the concurrent software system with this method. Meanwhile, the software modeling method has advantages of loose coupling, adaptability and traceability.展开更多
In order to fully realize semantic interoperability among distributed and heterogeneous applications on the web, a set of effective interoperability mechanisms is presented. This mechanism adopts service interactive i...In order to fully realize semantic interoperability among distributed and heterogeneous applications on the web, a set of effective interoperability mechanisms is presented. This mechanism adopts service interactive interfaces （SII） and service aggregative interfaces （SAI） modeled with abstract state machine （ASM） to abstractly describe the behavior of the invoked web service instances, which makes business processing accurately specify tasks and effectively solves the problems of communication and collaboration between service providers and service requesters. The mechanism also uses appropriate mediators to solve the problems of information and coinmunication incompatibility during the course of service interaction, which is convenient for service interoperability, sharing and integration. The mechanism＇ s working principle and interoperability implementation are illustrated by a use case in detail.展开更多
The stress state around circular openings,such as boreholes,shafts,and tunnels,is usually needed to be evaluated.Solutions for stresses,strains and ultimate bearing capacities of pressurized hollow cylinder are common...The stress state around circular openings,such as boreholes,shafts,and tunnels,is usually needed to be evaluated.Solutions for stresses,strains and ultimate bearing capacities of pressurized hollow cylinder are common cases.Stress analytical method for plane problem of a double-layered thick-walled cylinder subjected to a type of non-uniform pressure on the outer surface and uniform radial pressure on the inner surface is given.The power series method of complex function is used.The stress analytical solution is obtained with the assumption that two layers of a cylinder are fully contacted.The distributions of normal and tangential contact stress along the interface,tangential stress on the inner boundary and stresses in the radial direction at θ=0°,45° and 90°,are obtained.An example indicates that,when the elastic modulus of the inner layer of a double-layered thick-walled cylinder is smaller than that of the outer layer,the tangential stress is smaller than that in the corresponding point for a traditional cylinder composed of homogeneous materials.In that way,stress concentration at the inner surface can be alleviated and the stress distribution is more uniform.This is a capable way to enhance the elastic ultimate bearing capacity of thick-walled cylinder.展开更多
The next-generation optical network is a service oriented network,which could be delivered by utilizing the generalized multiprotocol label switching(GMPLS) based control plane to realize lots of intelligent features ...The next-generation optical network is a service oriented network,which could be delivered by utilizing the generalized multiprotocol label switching(GMPLS) based control plane to realize lots of intelligent features such as rapid provisioning,automated protection and restoration(P&R),efficient resource allocation,and support for different quality of service(QoS) requirements.In this paper,we propose a novel stateful PCE-cloud(SPC)based architecture of GMPLS optical networks for cloud services.The cloud computing technologies(e.g.virtualization and parallel computing) are applied to the construction of SPC for improving the reliability and maximizing resource utilization.The functions of SPC and GMPLS based control plane are expanded according to the features of cloud services for different QoS requirements.The architecture and detailed description of the components of SPC are provided.Different potential cooperation relationships between public stateful PCE cloud(PSPC) and region stateful PCE cloud(RSPC) are investigated.Moreover,we present the policy-enabled and constraint-based routing scheme base on the cooperation of PSPC and RSPC.Simulation results for verifying the performance of routing and control plane reliability are analyzed.展开更多
For many years, computer systems have emerged; they now occupy an important place in our daily lives. The growing needs and ever increasing use of computer systems have made application development more and more compl...For many years, computer systems have emerged; they now occupy an important place in our daily lives. The growing needs and ever increasing use of computer systems have made application development more and more complicated, The complexity of these applications poses problems such as reuse, installation, administration and evolution of applications. The development of applications is related to the evolution of paradigms and approaches to developing them. This paper presents different approaches and paradigms of development starting with the procedural approach, coming up for service, through the component and object-oriented approaches. Also, for each of the approaches we determine the advantages and limitations.展开更多
文摘A method for modeling crosscutting concerns in the concurrent software system is presented based on the aspect-oriented（A-O） technique and the statechart of unified modeling language （UML）. Modeled with UML statechart diagrams, the primary system functions and corresponding traversal features are enveloped into various orthogonal regions of a composite state. The mutual relationships between orthogonal regions are implied by the orders of broadcast events. Using a modular transition system as a basic computational model, the formalization description of A-O statechart models is proposed. The precise semantics of model elements and modeling procedures is given. The example study indicates that the separation strategy of crosscutting concerns is implemented in the design phase of the concurrent software system with this method. Meanwhile, the software modeling method has advantages of loose coupling, adaptability and traceability.
基金The Natural Science Foundation of Hunan Province (No.05JJ30122),the Education Department Foundation of Hunan Prov-ince (No.05C519).
文摘In order to fully realize semantic interoperability among distributed and heterogeneous applications on the web, a set of effective interoperability mechanisms is presented. This mechanism adopts service interactive interfaces （SII） and service aggregative interfaces （SAI） modeled with abstract state machine （ASM） to abstractly describe the behavior of the invoked web service instances, which makes business processing accurately specify tasks and effectively solves the problems of communication and collaboration between service providers and service requesters. The mechanism also uses appropriate mediators to solve the problems of information and coinmunication incompatibility during the course of service interaction, which is convenient for service interoperability, sharing and integration. The mechanism＇ s working principle and interoperability implementation are illustrated by a use case in detail.
基金Projects(50874047,51074014,51174014)supported by the National Natural Science Foundation of China
文摘The stress state around circular openings,such as boreholes,shafts,and tunnels,is usually needed to be evaluated.Solutions for stresses,strains and ultimate bearing capacities of pressurized hollow cylinder are common cases.Stress analytical method for plane problem of a double-layered thick-walled cylinder subjected to a type of non-uniform pressure on the outer surface and uniform radial pressure on the inner surface is given.The power series method of complex function is used.The stress analytical solution is obtained with the assumption that two layers of a cylinder are fully contacted.The distributions of normal and tangential contact stress along the interface,tangential stress on the inner boundary and stresses in the radial direction at θ=0°,45° and 90°,are obtained.An example indicates that,when the elastic modulus of the inner layer of a double-layered thick-walled cylinder is smaller than that of the outer layer,the tangential stress is smaller than that in the corresponding point for a traditional cylinder composed of homogeneous materials.In that way,stress concentration at the inner surface can be alleviated and the stress distribution is more uniform.This is a capable way to enhance the elastic ultimate bearing capacity of thick-walled cylinder.
基金supported by National Natural Science Foundation of China(No.61571061)Innovative Research Fund of Beijing University of Posts and Telecommunications (2015RC16)
文摘The next-generation optical network is a service oriented network,which could be delivered by utilizing the generalized multiprotocol label switching(GMPLS) based control plane to realize lots of intelligent features such as rapid provisioning,automated protection and restoration(P&R),efficient resource allocation,and support for different quality of service(QoS) requirements.In this paper,we propose a novel stateful PCE-cloud(SPC)based architecture of GMPLS optical networks for cloud services.The cloud computing technologies(e.g.virtualization and parallel computing) are applied to the construction of SPC for improving the reliability and maximizing resource utilization.The functions of SPC and GMPLS based control plane are expanded according to the features of cloud services for different QoS requirements.The architecture and detailed description of the components of SPC are provided.Different potential cooperation relationships between public stateful PCE cloud(PSPC) and region stateful PCE cloud(RSPC) are investigated.Moreover,we present the policy-enabled and constraint-based routing scheme base on the cooperation of PSPC and RSPC.Simulation results for verifying the performance of routing and control plane reliability are analyzed.
文摘For many years, computer systems have emerged; they now occupy an important place in our daily lives. The growing needs and ever increasing use of computer systems have made application development more and more complicated, The complexity of these applications poses problems such as reuse, installation, administration and evolution of applications. The development of applications is related to the evolution of paradigms and approaches to developing them. This paper presents different approaches and paradigms of development starting with the procedural approach, coming up for service, through the component and object-oriented approaches. Also, for each of the approaches we determine the advantages and limitations.
