Abstract. Building applications based on the reuse of existing components or services has noticeably increased in the geospatial application domain, but researchers still face a variety of technical challenges designing workflows for their specific objectives and preferences. Hence, means for automatic service composition that provide semantics-based assistance in the workflow design process have become a frequent demand especially of end users who are not IT experts. This paper presents a method for automatic composition of workflows for analyzing the impacts of sea-level rise based on semantic domain modeling. The domain modeling comprises the design of adequate services, the definition of ontologies to provide domain-specific vocabulary for referring to types and services, and the input/output annotation of the services using the terms defined in the ontologies. We use the PROPHETS plugin of the jABC workflow framework to show how users can benefit from such a domain model when they apply its constraintsdriven synthesis methods to obtain the workflows that match their intentions.

This paper proposes an enhancement for the ADRW algorithm to achieve dynamic fragmentation and object allocation in distributed databases. The algorithm adapts to the changing patterns of object requests with the objective to dynamically adjust the allocation schemes of objects in order to minimize the total servicing cost of all requests. Objects may be replicated or fragmented depending on patterns of reads and writes. Qualitative analysis was used to characterize the performance of the enhanced algorithm

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In recent years, the geospatial application domain has embraced component-based development and service orientation to support software reuse. However, due to the specific characteristics of geospatial applications, caused by complex and comprehensive analysis processes and heterogeneous data, the reuse of services faces particular barriers in this domain. Providing application experts without a strong programming or technical background with simple means to reuse these services is an important challenge. This paper describes how we followed the eXtreme Model-Driven Development (XMDD) paradigm to improve the reuse of geospatial services, namely by (1) performing rigorous service abstraction of geospatial tools to be reused in large scale applications, (2) using the java electronic tools integration (jETI) technology for enabling the remote execution and integration of services, and (3) supporting service composition at the user level by using the java application building center (jABC) process modeling framework. Concretely, we discuss how we improved the reuse of services for the assessment of the impacts of sea-level rise.