Program for Thursday, 10 January 2002

Our Next Meeting is scheduled for
Thursday, 10 January 2002
Bruce Barkstrom will be speaking on
Ada 95 Bindings for the Hierarchical Data Format (HDF)
Used for NASA’s Earth Observing System (EOS) Data and Information System (EOSDIS)

at Lockheed Martin in Rockville, Maryland

This will be a joint meeting between the DC and Baltimore SIGAda Chapters


To Members and Friends of DC SIGAda

Next Meeting:

Thursday, 10 January 2002, 7:30 P.M. (Refreshments and Social at 7:00 P.M.) at the Lockheed Martin Corporation in Rockville, Maryland. DC SIGAda and Baltimore SIGAda will feature a presentation titled: Ada 95 Bindings for the Hierarchical Data Format (HDF) Used for NASA’s Earth Observing System (EOS) Data and Information System (EOSDIS)

Abstract: Ada 95 Bindings for HDF

This presentation describes Ada95 bindings for HDF4 and HDF5, the current versions of the National Computational Sciences Alliance (NCSA) Hierarchical Data Format (HDF). These self-describing file formats are intended for storage of large, diverse collections of scientific data and for retrieving subsets of these data. The libraries also support data compression, chunking of large arrays, and automatic conversion of vendor-specific binary formats for a variety of data types.

HDF files are intended to provide self documenting storage of scientific data. This means that HDF provides structures that allow the file format to contain data about the file structure and descriptive information about the data contained in the file. By reading an appropriate sequence of data structures in the file, a data user can extract the information needed to understand the kind of data in the file, the size, shape, and data type of the arrays in the file, and even documentation about the file contents.

HDF is becoming widely used in scientific data holdings, such as those of NASA’s Earth Observing System (EOS) Data and Information System - EOSDIS. At present, EOSDIS is adding about one TB per day to NASA’s Earth Science data holdings. In the near future, this rate will increase to about three TB per day. The EOS Project has directed NASA Principal Investigators to use HDF for the data format for all EOS missions. Thus, this data format is very important to the author (he is Instrument Principal Investigator for the investigation of Clouds and the Earth’s Radiant Energy System: CERES), as well as many of his colleagues.


Dr. Bruce R. Barkstrom is currently Head of the Atmospheric Sciences Data Center at NASA's Langley Research Center in Hampton, VA. This data center is a scientific digital library that is currently processing, archiving, and distributing about 3 TB/month of data from two instruments on the NASA Terra Spacecraft, in addition to archiving and distributing data from many other data sources. Dr. Barkstrom has been actively engaged in work on NASA's Earth Observing System's Data and Information System (EOSDIS) over the last decade, receiving a NASA Exceptional Achievement Medal for his contributions to the system architecture and cost modeling for this system. He has developed a unique user model for this system, based on Markov models for user activities and innovation-diffusion models for the rate at which users become customers of such a system.

Before becoming Head of the Data Center, Dr. Barkstrom was Instrument Principal Investigator for the EOS investigation of Clouds and the Earth's Radiant Energy System (CERES), where he developed the CERES software system's architecture and data production logistics plans. In 1998 and 1999, Dr. Barkstrom spent a six month sabbatical supported by a NASA Langley Thompson Fellowship with the HDF Group at the National Computational Sciences Alliance (NCSA) in Champaign-Urbana, Illinois, investigating the application of the HDF data format to problems arising from tracking cloud systems on a global basis.

Bruce R. Barkstrom
Mail Stop 420
NASA Langley Research Center
Hampton, VA 23681-2199

Phone: +1 (757) 864-5676
FAX: +1 (757) 864-7996
Email: b.r.barkstrom@larc.nasa.gov


Lockheed Martin Corporation
9211 Corporate Boulevard
Rockville, Maryland 20874

From all points: Get to I-270 West from the I-495 Beltway,
1. Take I-270 West to Shady Grove Exit;
2. Turn left at light;
3. Turn right on Corporate Drive (at light);
4. Turn right at end of access road
   (You can only turn left or right);
5. Go to end of driveway.
6. The building for the meeting is on the right,
   opposite the open courtyard area. It is building #9211.
   Parking lots are on the left and right.
7. Enter main lobby. Stop at guard desk to check in.

Also, to obtain a map of the location, visit Mapquest, select Driving Directions for the destination address: "9211 Corporate Drive, Rockville, Md."

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We will have light foods and refreshment at 7:00. The meeting begins at 7:30 pm.

Many thanks to all earlier participants, contributors, speakers, advisors, and friends, who are involved in helping to produce and attend the meetings.

Please forward this message to people who might be interested in attending. We welcome all new members as our attendance and interests grow.

Consider registering for inclusion on our e-mail list. Registration instructions are provided on the DC SIGAda Web site.

Jeff Castellow, Chair, DC SIGAda

updated 23 December 2001