[mod.ai] Seminar - Spatial Objects in Database Systems

CALENDAR@IBM.COM.UUCP (01/29/87)

                     IBM Almaden Research Center
                           650 Harry Road
                       San Jose, CA 95120-6099

                          February 2-6, 1987


ACCESS STRUCTURES FOR SPATIAL OBJECTS IN NONTRADITIONAL DATABASE SYSTEMS
H.-P. Kriegel, University Wuerzburg, West Germany

Computer Science Seminar    Monday, Feb. 2    1:00 P.M.   Room:  B3-247

Database systems must offer storage and access structures for spatial
objects to meet the needs of nontraditional applications such as
computer-aided design and manufacturing (CAD/CAM), image processing
and geographic information processing.  First, we will show that
access methods for spatial objects should be based on multidimensional
dynamic hashing schemes.  However, even for uniform object
distributions, previous schemes of this type do not exhibit ideal
performance; for nonuniform object distributions which are common in
the above mentioned applications, the retrieval performance of all
known schemes is rather poor.  In this talk, we will present new
schemes which exhibit practically optimal retrieval performance for
uniform and nonuniform object distributions.  We will underline this
fact by the results of experimental runs with implementations of our
schemes.
Host: D. Ruland


Visitors, please arrive 15 minutes early.  IBM's new Almaden Research
Center (ARC) is located adjacent to Santa Teresa County Park, between
Almaden Expressway and U.S. 101, about 10 miles south of Interstate
280.  From U.S. 101, exit at Bernal Road, and follow Bernal Road west
past Santa Teresa Blvd.  into the hills (ignoring the left turn for
Santa Teresa Park).  Alternatively, follow Almaden Expressway to its
southern terminus, turn left onto Harry Road, then go right at the ARC
entrance (about a quarter of a mile later) and go up the hill.  For
more detailed directions, please phone the ARC receptionist at (408)
927-1080.