Select, Overlay, Explore; Integration of diverse data Distributed Data Heterogeneous coding, access Connects providers to users; Homogenize data access Voyager Data Federation Services Built and Used by a Virtual Community Layered Map Time Chart ProvidersUsers Vector GIS Data XDim Data SQL Table OLAP Web Images Voyager Federation Web Services Publish, Find, Bind Data & Tool Catalog Uniform Access/Retrieval Scatter Chart

The Dvoy Project DVOY is Federated Information System for heterogeneous, multidimensional datasets Voyager is a generic graphic browser for the federated DVOY data. The initial Dvoy infrastructure is being developed at CAPITA, with NSF supportDvoy Further services for data access, processing and viewing are expected from the community The project evolution is to ride 'web services wave‘ of the Internet CAPITA Support: –NSF ITRWorkgroup Collaboration Tool:Aug Aug 2004 –EPA Web-based Visibility:Aug Apr 2003 –NOAAASOS Visibility:Sep Sep 2002 –MARAMAChemical Trajectory Tool:Aug July 2003 –EPA OAQPS Global Transport Analysis:Nov 2002 – Oct 2003 –NSF DigiGov Fire and Smoke Network :May 2003 – Apr 2006 Pending –NASA ESE Satellite Appl. to PM Managment :June 2003 – May 2008 Pending In-kind support by organizations participating in DVOY-based federated data sharing Collaborators: CIRA (Schichtel), NRL(Westphal), NASA (Goddard)…many data sources.

Multi-Dimensional Data Model Data can be distributed over 1,2, …n dimensions 1 Dimensional e.g. Time dimension i j k j i Data Granule i 2 Dimensional e.g. Location & Time 3 Dimensional e.g. Location, Time & Parameter View 1 Data Space View 2 Views are orthogonal slices through multidimensional data cubes Spatial and temporal slices through the data are most common

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Render Service Chaining in Spatio-Temporal Data Browser Spatial Slice Find/Bind Data Data Cube Time Slice Time Portrayal Spatial PortrayalSpatial Overlay Time Overlay OGC-Compliant GIS Services Time-Series Services PortrayOverlay Homogenizer Catalog Wrapper Mediator Client Browser Cursor/Controller Maintain Data Vector GIS Data XDim Data SQL Table OLAP Satellite Images Data Sources

Data Stack: Overlay of multiple data layers Each DataCube may have 0-n dimensions Each dimension is assigned a view 3 D DataCube 2 D DataCube DataView 3 Layer 2 Layer 1 DataView 1 DataView 2 In a view, the number of layers is the number of datasets If a DataCube does not have a data for a view, a Null Layer is assigned Null Layer

Dvoy Data Flow and Processes DataView 1 View Data Abstract Portrayal Device Portrayal Render Device View Portrayal Device Driver Trans - mission Abstr.Data Access View Wrapper Physical Data Abstract Data Physical Data Physical Data reside in servers Data are accessed by view-specific wrappers yielding homogeneous abstract data ‘slices’ Abstract Data Abstract Data are virtual Abstract data are requested by viewers; homogeneous real data are delivered by abstract interface DataView 2 DataView 3 View Data View Data are enriched View data from abstract interface are enriched by parameters useful for portrayal/processing

Voyager: The Program The Voyager program consists of a stable core and adoptive input/output section The core executes the data selection, access portrayal tasks The adoptive, abstract I/O layer connects the core to evolving web data, flexible displays and to the a configurable user interface: –Wrappers encapsulate the heterogeneous external data sources and homogenize the access –Device Drivers translate generic, abstract graphic objects to specific devices and formats –Ports expose the internal parameters of Voyager to external controls Data Sources Controls Displays Voyager Core Data Selection Data Access Data Portrayal Adoptive Abstract I/O Layer Device Drivers Ports Wrapper s

Web Service Wrapper for TOMS Aerosol Index Fixed Geo-rectangle; Image Trim, daily TOMS Image Metadata Geo-rectangle (65, -180; -65, 180) Image Size (640, 480) Image Margins (40, 40, 30,30) Transparent Colors (0,0,255 ) Image Access Metadata URL template: :ftp://jwocky.gsfc.nasa.gov/pub/eptoms/images/aerosol/YYYYY/eaYYMMDD.gif StartDate, EndDate

Web Services Components and Actions Service providers publish services to a service broker. Service users find the needed service and get access key from a service broker With the access key, users bind to the service provider The result is a dynamic binding mechanism between the service users and providers Service Broker Service Provider Publish Find Bind Service User Components:Provider – User – Broker Actions: Publish – Find - Bind

Web Publish HTTP, FTP Voyager Data Wrapper Services Service Cataloger Service Consumer Ordinary web content can be delivered as a Web Service through a Proxy Server. The Wrapper Service converts HTTP/FTP service to XML Web service The Wrapper Service is published as a web service to the Broker The User finds the service from the broker and accesses the Wrapper to use the service Service Wrapper HTTP/FTP Service User Chain Find Publish Access SOAP, XML

Web Application: Chained Web Services A Web Service Provider may also be a User of other services Multiple web services can be chained into an interactive workflow system The result is an agile application that can be created ‘just in time’ by the user for a specific need Service Broker Service Provider/User Publish Find Bind Service User Chain Service Provider Bind Chain

Voyager Data Access Examples

Satellite and Surface detection of Aerosol pollution Origin of Clean (blue) Dirty (red) Air Masses to Vermont Time series display and selector

Quebec Fires, July 6, 2002 SeaWiFS, TOMS satellite and METAR surface data superimposed SeaWiFS satellite and METAR surface haze shown in the Voyager distributed data browser Satellite data are fetched from NASA GSFC; surface data from NWS/CAPITA servers

Trans-Atlantic Transport of Quebec Smoke July 11: Smoke approaching Europe July 10: Quebec smoke over Mid- Atlantic SeaWiFS Reflectance TOMS Absorbing Aerosol SeaWiFS Reflectance TOMS Absorbing Aerosol Spain E. US

Browsing of Distributed Data from HTTP/FTP Servers Land Reflectance from SeaWiFS Project, NASA GSFC AVHRR Oceanic Aerosol CAPITA, WashU, STL Fire Pixels, Jan 1997, European Space Agency

NRL Forecast Model for Dust, Smoke and Sulfate METAR Surface Haze Real-time model and surface observations are compared spatially and temporally Dust Sulfate Smoke METAR Haze Time Selector

Idaho Fires Example (August 2000) ASTR Fire Locations SeaWiFS Image showing smoke dispersion Satellite imagery and satellite fire observations are spatially integrated to show fire sources and smoke transport

Idaho Fires Example (August 2000) ASTR Fire Locations Processed SeaWiFS image showing aerosol optical depth Derived aerosol optical depth provides a focused look at smoke dispersion The SeaWiFS reflectance image is hidden to expose the aerosol optical depth image ‘below’ it

Dvoy Federated Information System Dvoy offers a homogeneous, read-only access mechanism to a dynamically changing collection of heterogeneous, autonomous and distributed information sources. Data access uses a global multidimensional schema consisting of spatial, temporal and parameter dimensions The global query capabilities yield slices along the spatial, temporal and parameter dimensions of the multidimensional data cubes The uniform global schema is suitable for data browsing and online analytical processing, OLAP The Dvoy Federated Information System is an open system, used and maintained by the air pollution research community