HUBzero allows you to create dynamic web sites that connect a community in scientific research and educational activities. HUBzero sites combine powerful Web 2.0 concepts with a middleware that provides instant access to interactive simulation tools. These tools are not just Java applets, but real research codes that can access TeraGrid, the Open Science Grid, and other national Grid computing resources for extra cycles. HUBzero was created by researchers at Purdue University in conjunction with the NSF-sponsored Network for Computational Nanotechnology. The technology was originally developed to support nanoHUB.org, a national resource for nanotechnology simulation. It has since been extended to create science gateways for other scientific domains.

A clearinghouse for ideas, news, and resources in support of citizen science-- partnerships between volunteers and scientists that answer real-world questions. managed by cornell

Scientists in a variety of disciplines (e.g., biology, ecology, astronomy) need access to scientific data and flexible means for executing complex analyses on those data. Such analyses can be captured as 'scientific workflows' in which the flow of data from one analytical step to another is captured in a formal workflow language. The Kepler project's overall goal is to produce an open-source scientific workflow system that allows scientists to design scientific workflows and execute them efficiently using emerging Grid-based approaches to distributed computation. Kepler is based on the Ptolemy II system for heterogeneous, concurrent modeling and design. Ptolemy II was developed by the members of the Ptolemy project at UC Berkeley. Although not originally intended for scientific workflows, it provides a mature platform for building and executing workflows, and supports multiple models of computation.

Metacat is a flexible metadata database. It utilizes XML as a common syntax for representing the large number of metadata content standards that are relevant to ecology. Thus, Metacat is a generic XML database that allows storage, query, and retrieval of arbitrary XML documents without prior knowledge of the XML schema.

The Metacat database models XML documents as a DOM tree, basically decomposing the nodes of the XML document and storing the node data as a series of records in a relational database via a JDBC connection. At this point, only Oracle and PostgreSQL have been tested as a backend databases, but we have avoided RDBMS specific features in order to maintain portability to other relational databases.

Metacat is implemented as a Java Servlet, and so communicates using basic HTTP protocol semantics. The figure below shows the basic structure of the Metacat architecture. A well defined interface for inserting, updating, deleting, querying, and transforming (using XSL) XML documents is presented. We would like to add the DOM API as an alternative supported mechanism for interacting with Metacat, but have not yet implemented this functionality.