A scientific workflow framework for scientific data querying and processing

Abstract

We are at the beginning of the new era of ``e-science\u27\u27. Researchers in many areas of science, especially in astrophysics, physics, climatology and biology, are now facing tremendous increases in data volumes, as well as corresponding data analysis tools. These increased data and tools demand a better framework to manage the new generation scientific research cycle from data capture, data curation to data analysis, data query and data visualization. Scientific workflows are proving to be one of the key technologies for scientists to formalize and structure complex scientific processes to enable and accelerate many significant scientific discoveries. Although several scientific workflow management systems (SWFMSs) are developed, a formal scientific workflow composition framework, in which workflows and constructs can be composed arbitrarily to process and query collectional scientific data sets, is still to be proposed. In this thesis, I make several contributions towards formalizing a scientific workflow composition framework. First, We proposed a dataflow-based scientific workflow composition model including a scientific workflow model that separates the declaration of the workflow interface from the definition of its functional body; and a set of workflow constructs, including Map, Reduce, Tree, Loop, Conditional, and Curry, which are fully compositional one with another. Our workflow composition framework is unique in that workflows are the only operands for composition; in this way, our approach elegantly solves the two-world problem in existing composition frameworks, in which composition needs to deal with both the world of tasks and the world of workflows. Second, We formalized a collection-oriented data model, called collectional data model, to model hierarchical collection-oriented scientific data, and a set of well-defined operators to manipulate and query such data. To our best knowledge, this is the first algebraic approach to modeling collection-oriented scientific data. Finally, we developed a prototype scientific workflow management system, called View. The View system implemented the above techniques in its subsystems and integrated them within a service-oriented architecture