[net.ai] AIList Digest V3 #19

LAWS@SRI-AI.ARPA (02/11/85)

From: AIList Moderator Kenneth Laws <AIList-REQUEST@SRI-AI.ARPA>


AIList Digest            Monday, 11 Feb 1985       Volume 3 : Issue 19

Today's Topics:
  Machine Translation - Slocum's System,
  Publications - Manual of Intensional Logic,
  Seminars - Algebraic Specifications (CSLI) &
    Massively Parallel Natural Language Processing (BBN) &
    Belief, Awareness, and Limited Reasoning  (CSLI) &
    The Logical Data Model (SU),
  Conferences - Evolution and Information &
    SCCGL Conference on General Linguistics
----------------------------------------------------------------------

Date: Sun 10 Feb 85 17:35:14-PST
From: LOUROBINSON@SRI-AI.ARPA
Subject: Machine Translation

Regarding a German/English translator: How about Jonathan Slocum's
program developed for Siemens?  Slocum is now at MCC in Austin
courtesy of the University of Texas.  Good luck.

Lou Robinson

------------------------------

Date: Wed 6 Feb 85 17:20:59-PST
From: Emma Pease <Emma@SU-CSLI.ARPA>
Subject: Lecture Notes - Manual of Intensional Logic

         [Excerpted from the CSLI Newsletter by Laws@SRI-AI.]


                    FIRST VOLUME OF CSLI LECTURE NOTES

The first in the series of CSLI Lecture Notes has just been published.
Entitled ``Manual of Intensional Logic,'' the 75-page book by Johan van
Benthem constitutes a graduate course that the author taught in the Winter
of 1984 while at CSLI.

``Intensional Logic as understood here,'' the author writes in the
Introduction, ``is a research program based upon the broad presupposition
that so-called `intensional contexts' in natural language can be explained
semantically by the idea of `multiple reference.' ''

Unlike CSLI Reports, the Lecture Notes will be sold for a nominal fee to
defray part of production costs. The price of ``Manual of Intensional
Logic'' is $5, and it may be purchased at the Stanford Bookstore or by
writing to Dikran Karagueuzian at the Center. A 25% discount is offered to
all members of the CSLI community or to anyone ordering three or more
copies to be used for instructional purposes. California residents should
add sales tax.

------------------------------

Date: Wed 6 Feb 85 17:20:59-PST
From: Emma Pease <Emma@SU-CSLI.ARPA>
Subject: Seminar Summary - Algebraic Specifications (CSLI)

         [Excerpted from the CSLI Newsletter by Laws@SRI-AI.]


                         SUMMARY OF AREA C MEETING
         ``Algebraic Specifications in an Arbitrary Institution''
                             Andrzej Tarlecki
               Dept. of Computer Science, Univ. of Edinburgh

The pioneering papers on algebraic specification used many-sorted
equational logic as a logical framework in which specifications were
written and analyzed.  Nowadays, however, examples of logical systems in
use include first-order logic, higher-order logic, infinitary logic,
temporal logic, and many others.  Note that all these logical systems may
be considered with or without predicates, admitting partial operations or
not.  This leads to different concepts of signature and of model, perhaps
even more obvious in examples like polymorphic signatures, order-sorted
signatures, continuous algebras, or error algebras.  The informal notion of
a logical system for writing specifications has been formalized by Goguen
and Burstall who introduced for this purpose the notion of institution.
The first and presumably most important application of this notion is its
use in the theory of algebraic specifications.  It turns out that most of
the work on algebraic specification, especially concerning specification
languages, may be done in an institution-independent way.  We briefly
present a collection of simple but very powerful specification-building
operations and give their semantics in an arbitrary institution.  In this
context we outline a very simple and mathematically elegant view of the
formal development of programs from their specifications.  The notion of
institution is also used to formulate (and prove) some model-theoretic
results at an appropriately general level.  We show how to generalize to an
arbitrary institution a Birkhoff-type characterization of quasi-varieties
as implicational classes.  This result may be used to prove that Mahr and
Makowsky's characterization of standard algebraic institutions which
strongly admit initial semantics holds for arbitrary institutions
satisfying a number of technical assumptions.  Finally, we briefly outline
some problems concerning the notion of institution itself.  We discuss the
need for some tool for constructing new institutions and for combining
institutions (``putting institutions together'').  We also indicate
possible generalization of this notion which would provide a mold for
richer semantical systems than just collections of sentences with a notion
of their truth.

------------------------------

Date: 8 Feb 1985 14:58-EST
From: Brad Goodman <BGOODMAN@BBNG>
Subject: Seminar - Massively Parallel Natural Language Processing (BBN)

           [Forwarded from the MIT bboard by JCMA@MIT-MC.]


            Massively Parallel Natural Language Processing

 Professor David L. Waltz, Thinking Machines and Brandeis University

Date:  10:00 a.m. Tuesday,  February 19, 1985
Place: Newman Auditorium
       BBN Laboratories Inc.
       70 Fawcett Street
       Cambridge, Ma.


This talk will describe research in developing a natural language
processing system with modular knowledge sources but strongly
interactive processing.  The system offers insights into a variety of
linguistic phenomena and allows easy testing of a variety of hypotheses.
Language interpretation takes place on an activation network which is
dynamically created from input, recent context, and long-term knowledge.
Initially ambiguous and unstable, the network settles on a single
interpretation, using a parallel, analog relaxation process.  The talk
will also describe a parallel model for the representation of context
and of the priming of concepts.  Examples illustrating contextual
influence on meaning interpretation and "semantic garden path" sentence
processing, along with a discussion of the building and implementation
of a large scale system for new generation parallel computers are
included.

------------------------------

Date: Wed 6 Feb 85 17:20:59-PST
From: Emma Pease <Emma@SU-CSLI.ARPA>
Subject: Seminar - Belief, Awareness, and Limited Reasoning  (CSLI)

         [Excerpted from the CSLI Newsletter by Laws@SRI-AI.]


  12 noon, 2/14         TINLunch
  Ventura Hall          ``Belief, Awareness, and Limited Reasoning''
  Conference Room       Ronald Fagin, IBM San Jose Research Laboratory

Possible-worlds semantics for knowledge and belief do not seem appropriate
for modelling human reasoning since they suffer from the problem of what
Hintikka calls ``logical omniscience''.  This means that agents are assumed
to be so intelligent that they must, in particular, know all valid
formulas.  Moreover, each agent's knowledge is also closed under deduction,
so that if an agent knows p, and if p logically implies q, then the agent
must also know q.  Unfortunately, this is certainly not a very accurate
account of how people operate!  People are not logically omniscient for
several reasons, including (1) Lack of awareness: how can someone say that
he knows or doesn't know about p if p is a concept he is completely unaware
of?  (2) People are resource-bounded: they simply lack the computational
resources to deduce all the logical consequences of their knowledge.  (3)
People don't focus on all issues simultaneously: it is possible for a
person to have distinct frames of mind, where the conclusions drawn in
distinct frames of mind may contradict each other.  Some new logics for
belief and knowledge are introduced which model these phenomena, so that,
in particular, agents need not be logically omniscient.  This talk
represents joint work with Joe Halpern.                    --Ronald Fagin

------------------------------

Date: Tue, 5 Feb 85 09:08:22 pst
From: Gabriel Kuper <kuper@diablo>
Subject: Ph. D. Oral - The Logical Data Model (SU)

         [Forwarded from the Stanford bboard by Laws@SRI-AI.]


                        Gabriel M. Kuper

        The Logical Data Model: A New Approach to Database Logic

                        9AM, 7 Feb. 985
                Building 420 (Psychology), Room 41


We propose a mathematical framework for unifying and generalizing the three
principal data models, i.e., the relational, hierarchical and network models.
Until recently most theoretical work on databases has focused on the relational
model, mainly due to its elegance and mathematical simplicity compared to the
other models.
Some of this work has pointed out various disadvantages of the relational model,
among them its lack of semantics and the fact that it forces the data to have a
flat structure that the real data does not always have.

The Logical Data Model (LDM) combines the advantages of both approaches.
It models database schemas as directed graphs, in which the leaves correspond to
the attributes, and the internal nodes to connections between the data.
Instances of LDM schemas consist of r-values, which constitute the data space,
and l-values, which constitute the address space.
This enables us to deal with instances of cyclic structures, but still get a
first-order theory.

We define a logic on LDM schemas in which integrity constraints can be
specified, and use it to define a logical, i.e. non-procedural, query language
that is analogous to Codd's relational calculus.
We also describe an algebraic, i.e. procedural, query language and prove that
the two query languages are equivalent.
These languages have a novel feature: not only can they access a non-flat data
structure, e.g. a hierarchy, but the answers they produce do not have to be flat
either.
Thus, the language really does have the ability to restructure data and not only
to retrieve it.

------------------------------

Date: Wed 6 Feb 85 17:20:59-PST
From: Emma Pease <Emma@SU-CSLI.ARPA>
Subject: Conference on Evolution and Information

         [Excerpted from the CSLI Newsletter by Laws@SRI-AI.]


                  CONFERENCE ON EVOLUTION AND INFORMATION

A conference on Evolution and Information with major support from CSLI will
be held at Stanford this April 19-21.  The specific focus of the conference
will be on the use of optimality models both in biology and in the human
sciences.  Papers will be contributed to the conference by biologists,
philosophers, psychologists, and anthropologists.  Apart from addressing
problems and limitations of optimality models within biology, an important
aim of the conference will be to explore the relevance of biological
results, either factually or methodologically, to other areas of inquiry.

Papers to be discussed at the conference will be circulated about a month
before the meeting.  Contributors will be asked to give a brief summary of
their papers at the conference sessions but papers will not be read.
Therefore, anyone who would be interested in seeing the papers in advance,
or would like any further information about the conference, should contact
John Dupre, Philosophy, Stanford University (415-497-2587, Dupre@Turing).

------------------------------

Date: Tue, 5 Feb 85 20:13:24 pst
From: li51x%sdcc3@SDCSVAX
Subject: SCCGL Conference on General Linguistics

CALL FOR PAPERS

SOUTHERN CALIFORNIA CONFERENCE ON GENERAL LINGUISTICS


APRIL 20-21, 1985

The Conference will be held at the University of California,
San  Diego.   Papers  from  any  of  the  subdisciplines  of
linguistics are eligible.  Graduate students are  especially
encouraged  to  participate,  and abstracts will be refereed
anonymously.

Please  provide  10  copies  of  your   single-page   titled
anonymous  abstract, and include an index card with the fol-
lowing information:

     Paper title (matching that on abstract)
     Author
     Address
     Phone number (including area code)

Please send abstracts to the address below before 28 February 1985.

     Chilin Shih
     SCCGL
     Linguistics, C-008
     UCSD
     La Jolla, CA 92093

Information about meals and  accommodation  will  be  mailed
later.   For further information call (619) 452-3600, Chilin
Shih, Carol Georgopoulos, or Diane Lillo-Martin.

You may reach Chilin at sdcc6!ix226@UCSD.arpa.   Please use SCCGL
as the subject heading.

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