[net.ai] AFLB

Broder@SU-SCORE.ARPA@SU-Score@sri-unix.UUCP (09/30/83)

From:  Andrei Broder <Broder@SU-SCORE.ARPA@SU-Score>

                [Reprinted from the SU-SCORE bboard.]


The "Algorithms  for  Lunch  Bunch"  (AFLB) is  a  weekly  seminar  in
analysis  of  algorithms  held   by  the  Stanford  Computer   Science
Department, every Thursday, at 12:30 p.m., in Margaret Jacks Hall, rm.
352.

At the first meeting this year, (Thursday, October 6) Prof. Jeffrey D.
Ullman, from Stanford,  will talk on  "A time-communication  tradeoff"
Abstract follows.

Further  information  about   the  AFLB  schedule   is  in  the   file
[SCORE]<broder>aflb.bboard .

If you want to  get abstracts of  the future talks,  please send me  a
message to put you on the AFLB mailing list.  If you just want to know
the title of the  next talk and  the name of the  speaker look at  the
weekly Stanford CSD  schedule that  is (or  should be)  sent to  every
bboard.
                      ------------------------

10/6/83 - Prof. Jeffrey D. Ullman (Stanford):

                       "A time-communication  tradeoff"

We examine how multiple  processors could share  the computation of  a
collection of values  whose dependencies  are in  the fom  of a  grid,
e.g., the estimation of nth derivatives.  Two figures of merit are the
time t the shared computation takes and the amount of communication c,
i.e., the number of values that  are either inputs or are computed  by
one processor and  used by another.   We prove that  no matter how  we
share the responsibility for computing  an n by n  grid, the law ct  =
OMEGA(n^3) must hold.

******** Time and place: Oct. 6, 12:30 pm in MJ352 (Bldg. 460) *******