We will investigate the concept of active information tiles to represent the context and information required by a user while performing a future task. Before a user leaves the desktop, he will use a novel authoring tool to prepare one or more tiles. Tiles are stored at a desktop repository, where they actively gather information that will be needed later. When they become relevant, tile summaries are delivered to the PDA.

We will experiment with information tiles, using as an application perinatal dispatch and transport programs at the Stanford and Packard Hospitals. These programs provide perinatal care, including transport for critically ill infants and high-risk maternity cases requiring referral to a regional center. The dispatch center, nursery, receiving doctors, and ambulance or helicopter teams, as well as the physicians and administrators of the referring hospital are involved in each transport incident. Since the process occurs outside of the regular patient admission routine, paper and disjoint computer records of relevant information are created many times over. With the help of relevant hospital staff we will demonstrate how information for each incident can be represented by an information tile which is continuously updated by participants at different locations: administrative information, test results, observed reaction to drugs, history of vital signs, status during transport, ambulance location, etc. Participants will in effect communicate with each other through the tile. This strategy will provide participants with a conceptual organization and context when interacting with the transport program information space. For example, the query facility will disambiguate the notion of "patient", "recent vital signs", or "phone messages", based on the tile that is currently relevant: the term "patient" is always taken to mean the patient described by the current tile.

The implementation of information tiles will require us to understand how to partition information spaces, and how to construct information composites that are fed from the larger digital library through standing queries. Our implementation will include an authoring component that makes it easy for users to build tiles and sequences of tiles that will fill their needs on the road. These tiles will need to be modifiable remotely, via the PDA. We also need to develop indexing and query processing facilities for tile histories (e.g., to discover the status of a patient an hour ago). Since the tile at the PDA may not contain the full history, the processing may have to be coordinated with the desktop server. We will build and demonstrate an active tile environment, and will evaluate its effectiveness for providing continuous information access at handheld devices.