期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：2010
卷号：XXXVIII-4-8-2/W9
页码：7-12
出版社：Copernicus Publications
摘要：UN World Food programme (WFP) is implementing its own Spatial Data Infrastructure (SDI), in the framework and following the guidelines developed by United Nations Geographic Information Working Group (UNGIWG) with the UNSDI initiative. This paper will present an updated situation report of WFP SDI implementation, project realized with the technical support of ITHACA association. Geodatabase content has been structured in a specific data model developed in UML. The geodatabase content includes reference and transportation datasets; this second component is specifically conceived to efficiently store all objects and attributes needed for logistic assessment, one of the WFP mandates. Especially for the use during emergencies, up-to-date information, system availability, redundancy and performances are key factors; for that reason WFP SDI architecture is based on a federated geodatabase structure, with replicas distributed at regional and local offices. Furthermore, streaming features are used to create and maintain aligned a set of read-only geodatabase instances; streaming environment is created and set to maintain geodatabase integrity, without having to establish strict constraints on the configuration of the different nodes. The objective is to realise a system made of several distributed instances, possibly on different DBMS platforms, automatically aligned with the master site, granting system redundancy, network load reduction and increasing performances through the implementation of load balancing procedures. The proposed solution would be able to grant the maximum level of availability, especially during emergencies and for users operating in difficult environmental condition and with different hardware/software configurations. Synchronization procedures provide the capability of keeping all nodes aligned and up-to-date, simplifying data management processes
