按一下以編輯母片標題樣式,按一下以編輯母片,第二層,第三層,第四層,第五層,*,Service Architecture of Grid Faults Diagnosis Expert SystemBased on Web Service,Wang Mingzan,Zhang ziye,Northeastern University,Shenyang,110004 China,The Eighth International Conference on Electronic Measurement and Instruments ICEMI2007,Outline,Introduction,OGSA (,Open Grid Services Architecture,),OGSA Based on Web Services,Grid Service Layer Base on OGSA,Application,Grid Nodes of Fault Diagnosis Expert Systems,Data Transfer,Conclusion,Introduction,With the advance of computer technology,the scale and complexity of modern system is increased dramatically.,Once some accidents take place,it will lead to tremendous loss.,The appearance of,faults diagnosis,and,fault-tolerant controlling technology,opens a new path for advancing the reliability of complex system.,The grid computing technology was firstly used in faults diagnosis expert system in the paper.,OGSA (,Open Grid Services Architecture,),OGSA Based on Web Services,Grid Service Layer Base on OGSA,Open Grid Services Architecture,OGSA Based on Web Services,User,Firstly,client,send request,to,the,Servlet,(Web service layer),residenting on Web,server through browser.,Servlet,is responsible for,calling corresponding,EJB(Enterprise Java Beans),components on,application server.,The,activated,component accesses,the backend data layer and,processes the data.,OGSA Based on Web Services,Then Servlet chooses the appropriate JSP program(Web service layer)and transfers the result,JSP returns the result in the form of HTML to browser.,Client can be the Java application procedure,CORBA customer or the service partner.They separately communicate with the EJB component through the different protocol.,OGSA (,Open Grid Services Architecture,),OGSA Based on Web Services,Grid Service Layer Base on OGSA,Open Grid Services Architecture,Grid Service Layer Base on OGSA,The grid services include,procedure execution,data service,and so on.,With the appearance of these services,OGSA will turn into useful Service-Oriented Architecture(SOA).,Grid Service Layer Base on OGSA,The strategy of task dividing will affect directly the,load balance,the,communication complexity,and the,dependence,of the tasks,(1)Based on the,deserializing,analysis,develop the public service and the parallel service in server.This step needs to deploy every parallel service to all nodes in the grid.,(2)According to the number of parallel nodes in the grid,call threads in the client,each can visit the parallel service.,(3)Monitor the status of these threads,perform fault diagnoses and compile the result.,Grid Service Layer Base on OGSA,DGMA Based on Fault Diagnosis Expert Systems,Grid Service Layer Base on OGSA,In the solution above,the server end in the grid nodes process main service logic,the client end need,only start multi-threads,to call and monitor the completion condition of service.,Therefore,it reduces the clients load and achieves the application,deserializing,.,Application,Application,Grid Nodes of Fault Diagnosis Expert Systems,Data Transfer,Grid Nodes of Fault Diagnosis Expert Systems,The server is composed of two grid nodes.They are grid nodes for,spectral analysis,and the,data trend analysis,respectively.,Java language is used to write Web Service program,which realizes the grid computation and access process in the clients and the servers.,the grid nodes can also analyze the load of current node.So it can schedule the grid-cell resources more reasonably,which is especially important for the application of large-scale grid.,Application,Application,Grid Nodes of Fault Diagnosis Expert Systems,Data Transfer,Data Transfer,The experimental environment of the design is established in LAN.,We use 4 PC to construct a grid middleware.,In Grid-based Fault Diagnosis Expert System,the data transfer uses the way of,GridFTP,Then used API function to realize data transfer through Java Cog Kit.,Data Transfer,(1)Establish a Spec of transmission task,this Spec is similar to RSL;,(2)Set the source address and the destination address in transmission,and begin using the third party to transmit;,(3)Establish a transmission serve for the data resources of the source address;,(4)Establish a transmission service for the data resources of the destination address;,(5)Join the source address service and the destination address service to the service,in order to realize data transmission between two services;,(6)Submit the duty and realize data transmission.,Data Transfer,The system uses API provided by Java Cog Kit to carry out service submission.Cog Kit uninterruptedly intercepts execution status of accepting the work node through Status Listener.In Cog Kit,the execution situation of work is,SUBMITTED,FAILED,and,COMPLETED,Respectively.,In the client-end,we maintain a thread table.It includes thread number,state(0,moving,;1,moving failure,;2,normal,terminating,),Data Transfer,Through above application,it can reduce the transfer,latency brought,by the network.,Moreover,the jobs are no