Ressarch On Pattern-driven GIS Application Integration

In the current research of GIS application integration, there are problems of lack ofintegration theory, imperfect integration model partitioning, insufficient technology openness, nouniform framework system and so on. Based on theory of system integration and thoroughresearch for component-based software layer design and application integration technology,this paper introduces a pattern-driven GAI framework, makes an in-depth and systematicstudy separately from architectural pattern, design pattern and implementation pattern at threelevels, and demonstrates the results of this study through a GAI design example in egovernment.This paper effectively implements introducing EAI framework pattern, layered softwarearchitecture and component assembled theory into pattern-driven GAI framework study,proposes three levels of GAI framework - layered GAI integration architecture (LGIA) pattern,GAI design pattern based on atomic assembled integration and GAI implementation patternbased on application oriented components (AOCs) and composition operators, and gives thecorresponding mathematical definition and characterization description, demonstrates therelationship and the interaction mechanism between three levels in framework.This paper, separately based on tight integration, full integration and loose integrationmanners in GAI design pattern, makes a study of GAI Implementation pattern, points outabstraction layers in GAI architecture pattern correspond to three integration manners andtheir implementation technique or method, and gives the corresponding GAI frameworkmathematical definition. GIS cooperation integration in tight integration mode adoptscollaborative integrated mechanism based on web layer; GIS decoupling Integration in fullintegration mode is a high coupled complex integration, needs "two decoupling" consisting of"primary decoupling" based on workflow technology and "Advanced Decoupling" based onlightweight integration framework to decouple; The key of GIS parallel integration based onloose integrated mode lies in data integration, and some implementation techniques andmethods are proposed, which oriented to different layers.In this paper, through establishing LGIA theoretical system and studing its workingmechanisms and implementation model, the process of building a GIS integrated systembased on LGIA is proposed, the GIS integrated system design strategy based LGIA is given,complex GIS integration is transformed into systematic hierarchical design. The differentlayers use suitable integration patterns, so that all layers can focus on solving the integrationissues at different layers in GIS integration, to achieve loose coupling and goodinteroperability between the layers. It provides a new method and idea for GIS integrated system design.