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C00002 00002	JEANNE: THIS IS THE LONG REPORT:
C00045 00003	JEANNE: THIS IS THE SHORT SUMMARY:
C00059 00004	BIBLIOGRAPHY
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JEANNE: THIS IS THE LONG REPORT:

PROJECT 2: WORKBENCH FOR KNOWLEDGE REPRESENTATION
		Investigator:  Douglas B. Lenat


1. Objectives


The major objective  is to transfer  artificial intelligence expertise  to
various  applications,  primarily  medical,  by  creating  large  software
packages which can  be shared  among these  different tasks.   The set  of
tools  constitutes   a   workbench  for   knowledge   engineers,   thereby
facilitating the rapid construction of expert knowledge-based programs and
the advancement of core research (qv) of the project.

This year,  our efforts  have focused  on applying  our existing  packages
(AGE,  EMYCIN,  UNITS)  to  new  medical  tasks,  and  on  designing   and
constructing an  entirely new  tool,  RLL (since  this is  primarily  core
research, please see that section for information about RLL).  The  EMYCIN
package was applied to the problem of diagnosing various blood coagulation
disorders; of  some  interest  is  the relatively  small  amount  of  time
required for this  implementation (a  few weeks).  The  UNITS package  has
been  augmented  by  a   more  sophisticated  package  for   automatically
explaining its reasoning  to the watching  human user.  It  has been  used
extensively by molecular biologists.  The AGE system has generated so much
interest that  a week  long seminar  was conducted,  to instruct  a  dozen
researchers in its use.



2. Studies and Results


	2.1 Using EMYCIN for Diagnosis of Blood Coagulation Disorders


The development of a new medical consultant has allowed us to test of  the
current knowledge  acquisition facilities  of EMCYIN.   The system,  named
CLOT, is designed  to diagnose  various blood coagulation  disorders in  a
patient.  It requests details about a current episode of bleeding, various
facts from the patient's medical history, and the results of a battery  of
coagulation screening  tests.   From  this  information  CLOT  infers  the
presence and type of  the patient's coagulation defect  (if any) and  then
attempts to isolate the specific enyzmatic deficiency or platelet  defect.
These diagnoses can be  used by a physician  to estimate the severity  and
cause of a particular episode of bleeding, evaluate the effects of various
anti-coagulation therapies on  a patient, and  estimate the  pre-operative
risk of a patient having serious bleeding problems during surgery.

Constructed with  the help  of David  Goldman, a  medical student  at  the
University of Missouri,  CLOT was implemented  following approximately  10
hours of discussion about the contents of the knowledge base and was  then
entered and debugged using EMYCIN in another 10 hours.  The knowledge base
contains approximately  60  rules  and a  comparable  number  of  clinical
parameters.  It  must be  emphasized  that this  system is  a  preliminary
version of a more substantial consultant  and we make no claims about  the
current version's level of clinical  expertise. However, we feel that  the
structure of the knowledge base, in terms of the tasks it performs and the
manner in which  it pursues these  tasks, reflects the  major factors  and
reasoning strategies required for expert performence in this domain.

We found that the knowledge acquisition tools of EMYCIN had  substantially
improved since  the  construction of  SACON,  the last  EMCYIN  consultant
program.  We found that these facilities  now performed a large amount  of
useful checking and default specification  regarding the form and  content
of a  knowledge  base.  In  particular,  there  is a  new  facility  which
provides aid  when  acquiring  and  specifying  the  context  tree  for  a
consultant, eliminating a substantial amount of the tedium required to set
up the multitude of associated data structures for each context and ensure
their consistency.   In  addition,  the facility  for  acquiring  clinical
parameters of a context now does a significant amount of value checking on
the basis of a simple parameter classification scheme which we also  found
very helpful.

We made  use of  the new  ARL (Abbreviated  Rule Language)  facility  when
acquiring  the   rules  for   CLOT.   Designed   to  capitalize   on   the
stereotypically terse expression of rule  clauses by experts, ARL  reduces
the amount of typing time and,  again, ensures the correct forms are  used
for specifying the premise  functions.  In addition to  ARL, the new  rule
clause  subsumption   checker  also   proved   very  useful   during   the
specification of  the  larger  rule  sets in  the  system.   This  checker
analyzes each new rule for any syntactic subsumptions or equivalences with
the premise clauses of  other rules.  We found  that, for the larger  rule
sets, the premise clauses were sometimes specified with identical  premise
clauses, due either to  a typing mistake  or an actual  error in the  rule
specification. The checker detected  these inconsistencies and provided  a
graceful method of dealing with them.

In addition to testing the existing facilities for acquiring the knowledge
required for a new consultant, we have used this experience to investigate
other potential  methods for  improving these  facilities.  In  fact,  the
primary motivation for constructing this consultant was to explore the use
of more generic knowledge  about performing diagnosis  to guide and  focus
the acquisition of a diagnosistic  consultant for a specific domain.   The
major hypothesis  of this  exploration is  that there  are concepts  about
doing  diagnosis  in  general,  that  are  independent  of  a   particular
application and that can be used to suggest tasks and strategies which  an
expert might  consider when  formulating his  knowledge about  a  specific
diagnostic task.  We recorded the sessions in which CLOT was specified and
derived an outline of the major topics that were introduced and  discussed
during the specification.  In spite of the systems' relatively small size,
the CLOT example  demonstrated that  these generic  concepts were  useful,
that they did  serve to  focus and guide  the discussions,  and that  they
could be  used  to suggest  new  topics that  the  expert felt  he  should
consider in  this  domain.   We are  currently  implementing  a  knowledge
acquisition  system  which  makes  use  of  these  generic,  task-specific
concepts to interact with the expert.


	2.2 Augmenting the User Interface to UNITS


The  Units  system  is  a  powerful  and  flexible  frame-based  knowledge
representation package, developed in the  context of experiment design  in
molecular genetics. It has since been employed in a variety of other  uses
in that domain,  and is being  tried on applications  outside genetics  as
well.

The primary purpose of the Units system is to facilitate the  construction
of large knowledge  bases by  the individual domain  experts.  Because  of
this,  the   front-end  of   the   system  must   be  friendly   to   non-
computer-proficient  users.   Many  different  types  of  information  are
included  in  a  molecular   genetics  knowledge  base;  these   different
information types are described by using small editing systems specialized
to the particular type.  For example, much of the knowledge about  nucleic
acid structures  is  commonly described  in  the  form of  maps  of  those
structures.  The maps show the location of genes and control regions,  and
also the  location  of the  cutting  sites of  restriction  endonucleases.
Significant effort went into designing a map editor that provided for both
facile input and output. [See Appendix ].  This map editor, in conjunction
with  the  remainder  of  the  genetics  knowledge  base,  is  proving  an
invaluable tool  for  the  analysis of  nucleic  acid  structures.   Users
typically enter raw sequence  data about a new  structure and then,  using
English-like rules, create many  different types of  maps relating to  the
structure.  The time  to create  these maps has  been reduced  by over  an
order of magnitude from the previous  best method, and their accuracy  and
readability has increased greatly.

This year, the  UNITS group  has reorganized  the UNITS  files to  include
Masterscope information, to facilitate  automatic explanation of what  the
program is doing. Some minor internal cleanup and simplification followed.
We sent the files to Dr. Reid Smith at DREA in Canada and he made  further
simplifications, including removal of the  status files and creation of  a
new reference  manual.  Tapes  have been  requested from  as far  away  as
Japan, as well as domestic sites (e.g., Dr. Nancy Martin at UNM.)

The map-making and sequence analysis function of the Units system, a  side
benefit of the knowledge  base construction effort, is  now being used  by
many groups at Stanford among them those of Professors Paul Berg,  Stanley
Cohen,  Laurence  Kedes,  and  Douglas  Brutlag.   The  utility  of   such
representation work underscores the need  for work on the human  interface
in knowledge  representation  systems, as  well  as the  realization  that
different types of information, even if internally represented in  similar
ways, should be externally presented in a custom-designed manner.  It also
shows  the  importance  of  providing  user-accessible  control  over  the
manipulation of knowledge, in this case the English-like rule language.

The following is  a statement from  Dr. Brutlag:  "I  have discovered  the
beauty of focus and direction in kb (knowledge base) making.  By  limiting
our kb to a  very small set  of problems we now  have an extremely  useful
knowledge base.  With the help of Peter [Friedland], who has provided some
of the best  editors and datatype  handlers that I've  seen for  molecular
type of information, we have made a  useful knowledge base in that it  not
only allows us to store and  edit very complex information and rules,  but
it lets us  process it  with powerful sets  of production  rules that  are
written practically in biochemease.  I currently use the kb and our set of
rules in everyday  use in  the laboratory.  I  have also  been invited  to
present  a  talk  on  our  work  in  Heidelberg  Germany  this  month   to
biochemists.  Maybe I can  stir up some interest  in AI among this  group.
Anyway, I still am having some problems in the data acquisition phase.   I
can organize data and think of production rules about 10 times faster than
I can enter it into the current editors.  My time would be better spent if
I could enter rules and data in  a more free format like using a  standard
text editor.  Eventually we might have a  rule parser that can read a  set
of rules written in a freer style directly from a text file."

As is  clear from  Brutlag's note,  the current  MOLGEN UNITS  package  is
already a useful  tool, and its  usage points out  areas in which  further
development should proceed.

A case study  of the  use of  UNITS is presented  as an  appendix to  this
report.


	2.3 Time-Oriented Knowledge Representation Package


One direction for the workbench section of this project is the development
of tools for representing  knowledge about time-varying situations.   This
work has concentrating on the  process of turning one application  program
into a  more  general  representation package.   The  application  program
(called VM) was designed for real-time interpretation of measurement  data
from patients  in the  intensive care  unit using  a rule-based  approach.
This program was designed specifically  around the problem of  aggregating
many separate determinations  of patient  measurements taken  a period  of
time into a historical record of changes in the patient's status.

The first step  in the development  of a useful  package from an  existing
program is the identification of the particular simplifying assumptions of
the application area. VM took advantage of the fact that the ambiguity  of
the domain was  primarily due  to changes in  therapeutic context,  rather
than from  poor signal  sources, or  a  very imprecise  theory of  how  to
interpret the  signal  data.   The  representation  of  these  therapeutic
contexts is limited by the assumption that only one of these contexts  can
be used  to describe  the current  setting.  The  current design  for  the
time-oriented package allows for a more flexible representation that  will
allow for more ambiguity (from all sources) but maintain a simple  control
structure (forward-driven processing) for manipulating the representation.
This  is  accomplished  by  attaching  measures  of  belief/certainty   to
aggregates of conclusions that have been derived over a period of time.


	2.4 A Workshop to Disseminate the AGE System

In the AGE system an attempt has been made to isolate inference,  control,
and representation techniques from a few previous knowledge-based systems,
and  reprogram  them  for  domain  independence.   AGE  is  a  library  of
building-block programs (called "components")  combined with an  interface
that assists the user  in the design  and construction of  knowledge-based
programs.  It is  hoped that  AGE will speed  up the  process of  building
knowledge-based programs and facilitate the dissemination of AI techniques
by:  (1) packaging common AI software tools so that they do not need to be
reprogrammed for  every  problem;  and  (2) helping  people  who  are  not
knowledge-engineering specialists write knowledge-based programs.

The  components  in  AGE  have  been  carefully  selected  and   modularly
programmed to be useable  in combinations.  For  those users not  familiar
enough to experiment with combining the components, AGE currently provides
the user two predefined configuration of components--each configuration is
called a  "framework".  One  framework  uses the  concepts of  a  globally
accessible data structure called  a "blackboard", and independent  sources
of knowledge which cooperate to form hypotheses.  The Blackboard model has
been modified  to  allow  flexibility in  representation,  selection,  and
utilization of knowledge.  The other  framework (called Backchain) is  for
building programs  that  use  backward-chained  production  rules  as  its
primary method of generating inferences.

To support  the user  in  the selection,  specification,  and use  of  the
components, AGE is  currently organized around  several major  interacting
subsystems:  BROWSE (guides the user in browsing through the  hierarchical
descriptions of components and their use); DESIGN (guides the user in  the
design and  construction of  his  program through  the use  of  predefined
configuration  of   components);  ACQUISITION   (acquiring   task-specific
information); INTERPRETER (modules that  help the user  run and debug  his
program);  EXPLANATION  (replay  AGE's   execution  steps  and  list   the
justifications for the actions).

AGE-1 has been available to limited number of users on experimental  basis
since October, 1979.  A more public  version is scheduled to be  available
in early July, 1980.

A three-day workshop  was conducted on  the week  of March 4,  1980 for  a
limited number  of  people  who  had requested  access  to  AGE.   Without
exception the  attendees represented  organizations that  wished to  build
knowledge-based programs, but could not do so because of lack of qualified
AI programmers.  The aim of the workshop was to familiarize the user  with
AGE (many of them needing help in learning Interlisp language) and to have
a running program by the end of the workshop.  Each attendee was  required
to bring his own problem to be implemented.  The names of the organization
that sent attendees to the workshop, and brief description of the problems
they are interested in implementing on AGE are listed below:

Information    Science    Group,    University    of    Missouri-Columbia:
Interpretation  of  test  results  for  determining  the  cause  of  blood
coagulation  problems  in  patient   with  excessive  bleeding.   If   the
interpretation problem can be successfully implemented, they will go on to
implement a program that recommend anticoagulant therapy.

Institute of  Medical  Electronics,  University of  Tokyo:   Diagnosis  of
cardiovascular disease  using  diverse  data and  knowledge,  and  therapy
recommendation with re-evaluation  diagnosis.  In general,  this group  is
interested in building programs that  serve as research tools rather  than
as applied clinical tools.

Department of Psychology, University of Colorado:  This group is using the
Blackboard framework  in  AGE to  build  a psychological  model  of  prose
comprehension.  They had been  using AGE since a  few months prior to  the
workshop.

Oak   Ridge    National    Laboratory:    Interpretation    of    physical
signals--non-medical application.

Schlumberger-Doll   Research   Center:     Interpretation   of    physical
signals--non-medical application.
	


3. Goals for the Coming Year


The application of EMYCIN to  medical tasks should continue unabated  this
year.  In particular, the CLOT group is currently implementing a knowledge
acquisition system which makes use of the generic, task-specific  concepts
(the ones isolated  this year)  to interact  with the  medical expert,  to
assist him  in  staying "focussed"  during  the diagnostic  process.   The
self-explanation capabilities added  to UNITS  will be  tested in  several
domains this coming year, and may lead to better ideas about  explanation,
and thence an even better facility for EMYCIN.

Dr. W. F. Bodmer of the  British Imperial Cancer Research Fund  Laboratory
has just been provided with  access to and instruction  in the use of  the
MOLGEN UNITS system.  He intends to distribute it to his staff  scientists
to use  in  their routine  work.   The map-making  and  sequence  analysis
facilities which were  developed to facilitate  the construction of  large
knowledge bases rapidly, are  of chief interest to  him.  As Dr.   Douglas
Brutlag requests  in his  above quoted  letter, one  thrust of  the  UNITS
development work will be to make the editors "faster".  This does not mean
run faster, since they take very little computer time even now; rather  it
means a kind of human engineering, a  tailoring of the editors to the  way
in which scientists want to enter their knowledge.

Besides the current  focus on increasing  system efficiency (ie.   garbage
collection), we are revising the internal UNITS representations to provide
further simplifications and easier  use.  A new  paging algorithm is  also
under study.

The basic UNITS access  files are now  being used in  AGE as an  auxillary
data base.  We shall experiment to  locate any synergy which derives  from
this combination of two of our most powerful tools.

The work on time-oriented reasoning is continuing and being generalized in
such a way as to automate the generation of multiple expectations for  the
appropriate  ranges  for  incoming  data  based  on  uncertainty  in   the
determination of the current  context.  These changes  will provide for  a
larger number of  potential applications of  the time-base  representation
system.

Although there has been some  use of AGE, there  needs to be an  extensive
test of its  capabilities.  We  intend to implement  a relatively  complex
application problem ourselves that would serve as this test.  At the  same
time we will use feedback from outside users to improve the system.

For AGE-2,  our  plan  is to  improve  the  user interface  so  that  non-
specialist in knowledge-based programs can  use the system without  having
to attend a workshop.  It includes extensive research into the problem  of
determining appropriate knowledge representation and processing for  given
tasks.  This involves characterizing  problems in a  variety of ways,  and
matching the characterizations with those  in the various framework  still
to be implemented.

RLL (see the  section on core  research for details)  is now  sufficiently
fully implemented  to  be  chosen for  development;  several  groups  have
expressed interest in using it as a tool to facilitate the construction of
expert programs for their tasks; these include Stanford's Dr. Harold Brown
(VLSI layout  task),  Rand's Dr.   Frederick  Hayes-Roth  (Analogy-finding
task), and Stanford's Dr. Douglas Brutlag (Evolutionary genetics  pathways
task).  Lenat (RLL) and  Stefik (Molgen UNITS) have  been asked to be  the
co-presenters of a special tutorial on tools for knowledge engineering  at
this  summer's  AAAI  conference   (American  Association  for   Artifical
Intelligence).  Lenat has also  organized (in conjunction with  Hayes-Roth
and Waterman of  Rand) a  workshop on  Expert Systems,  for August,  1980.
These two activities are expected to lead to a new synthesis of  knowledge
engineering, to appear as both a survey article and a book.

As this program's charter indicates,  such applications (both medical  and
nonmedical) lead to  improved knowledge engineering  tools, which in  turn
facilitate the  creation of  future expert  systems.  The  specific  plans
mentioned above illustrate this theme.



APPENDICES

Please include Appendix D from the MOLGEN proposal.
If Peter Friedland can't get you (or Ed) one electronically,
then you'll have to Xerox it from the document itself.


JEANNE: THIS IS THE SHORT SUMMARY:

PROJECT 2: WORKBENCH FOR KNOWLEDGE REPRESENTATION
		Investigator:  Douglas B. Lenat

1. Objectives

The major objective  is to transfer  artificial intelligence expertise  to
various  applications,  primarily  medical,  by  creating  large  software
packages which can  be shared  among these  different tasks.   The set  of
tools  constitutes   a   workbench  for   knowledge   engineers,   thereby
facilitating the rapid construction of expert knowledge-based programs and
the advancement of core research.  This year, our efforts have focused  on
applying our existing packages (AGE, EMYCIN, UNITS) to new medical  tasks,
on generalizing  our  VM  package  for  time-oriented  reasoning,  and  on
constructing an entirely new tool, RLL.

2. Studies and Results

The development of a new medical consultant program, CLOT, has allowed  us
to test of  the current  knowledge acquisition facilities  of EMCYIN.   It
diagnoses various  blood coagulation  disorders in  a patient,  given  his
medical history and current coagulation screening tests.  CLOT attempts to
isolate the  specific  enyzmatic  deficiency or  platelet  defect.   These
diagnoses can be used by a physician to estimate the severity and cause of
a  particular  episode  of  bleeding,  evaluate  the  effects  of  various
anti-coagulation therapies on  a patient, and  estimate the  pre-operative
risk of a patient having  serious bleeding problems during surgery.   CLOT
was implemented following approximately 10  hours of discussion about  the
contents of the  knowledge base and  was then entered  and debugged  using
EMYCIN in another 10 hours.  The knowledge base contains approximately  60
rules and a comparable number of clinical parameters.  One new feature  of
EMYCIN useful  in  the rapid  implementation  of CLOT  was  the  automatic
checker (and default value specifier)  for values of clinical  parameters.
The major hypothesis of this exploration is that there are concepts  about
doing  diagnosis  in  general,  that  are  independent  of  a   particular
application  and  that  can  be   used  to  suggest  relevant   strategies
opportunely.

The UNITS  system is  designed  to facilitate  the construction  of  large
knowledge bases by individual domain experts.  Hence the front-end of  the
system must be friendly to non-computer-proficient users.  For its use  by
molecular  geneticists,  we   developed  a   special-purpose  editor   for
manipulating maps of nucleic acid  structures.  Users typically enter  raw
sequence data about a  new structure and  then, using English-like  rules,
create many different types of maps  relating to the structure.  The  time
to create these maps has been reduced  by over an order of magnitude  from
our previous best method, and it is now used here by Professors Paul Berg,
Stanley Cohen, Laurence Kedes, and Douglas Brutlag.

We sorely need tools  for dealing with  time-varying situations.  VM,  one
application program, took advantage of the fact that the ambiguity of  the
domain was primarily due  to changes in  therapeutic context, rather  than
from poor signal sources, or a  very imprecise theory of how to  interpret
the signal  data.  The  representation of  these therapeutic  contexts  is
limited by the assumption that only one  of these contexts can be used  to
describe the current setting.  A new general time-oriented package  allows
for a more  flexible representation, permitting  more ambiguity (from  all
sources)  but  maintaining  a  simple  control  structure  (forward-driven
processing) for manipulating the representation.  This is accomplished  by
attaching measures of belief/certainty  to aggregates of conclusions  that
have been derived over a period of time.

In the AGE system an attempt has been made to isolate inference,  control,
and representation techniques from a few previous knowledge-based systems,
and reprogram them for domain  independence.  AGE-1 has been available  to
limited number of users on experimental basis since October, 1979.  A more
public version  is scheduled  to  be in  early  July, 1980.   A  three-day
workshop was conducted on the week of  March 4, 1980 for a limited  number
of people  who  had  requested  access  to  AGE.   Without  exception  the
attendees represented organizations that  wished to build  knowledge-based
programs, but could not do so because of lack of qualified AI programmers.
The aim of the workshop was to familiarize the user with AGE (many of them
needing help in learning Interlisp language) and to have a running program
by the end of the workshop.  Each  attendee was required to bring his  own
problem to  be  implemented.   Two non-medical  applications  groups  were
represented,  and  several  medical  ones:   Information  Science   Group,
University of  Missouri-Columbia:   Interpretation  of  test  results  for
determining the  cause  of  blood coagulation  problems  in  patient  with
excessive bleeding.   Institute  of  Medical  Electronics,  University  of
Tokyo:  Diagnosis of  cardiovascular disease.   Department of  Psychology,
University  of  Colorado:   Building   a  psychological  model  of   prose
comprehension.


3. Goals for the Coming Year

The CLOT group  is currently implementing  a knowledge acquisition  system
which makes use of the generic, task-specific concepts (the ones  isolated
this year) to interact with the  medical expert, to assist him in  staying
"focussed"  during   the   diagnostic   process.    The   self-explanation
capabilities added to UNITS will be tested in several domains this  coming
year, and may lead to better  ideas about explanation, and thence an  even
better facility for EMYCIN.   Dr.  W.  F. Bodmer  of the British  Imperial
Cancer Research Fund Laboratory is distributing the MOLGEN UNITS system to
his staff scientists to use in their routine work.  At the request of  Dr.
Douglas Brutlag,  the UNITS  editors will  be made  "faster" (not  running
faster, but  rather  a  tailoring of  the  editors  to the  way  in  which
scientists want  to enter  their knowledge.)   The work  on  time-oriented
reasoning is continuing, by trying to automate the generation of  multiple
expectations for  the incoming  data.   That is,  what is  an  appropriate
ranges for each parameter, and how can these be determined  automatically?
For AGE-2,  our  plan  is to  improve  the  user interface  so  that  non-
specialist can  use  the  system  without having  to  attend  a  workshop.
Additionally, both RLL  and AGE  are candidates  for several  applications
this year.  As this program's  charter indicates, such applications  (both
medical and  nonmedical) lead  to  improved knowledge  engineering  tools,
which in  turn facilitate  the  creation of  future expert  systems.   The
specific plans mentioned above for each project illustrate this theme.
BIBLIOGRAPHY

.group
	(157) <<HPP-79-3>
	Nelleke Aiello, H. Penny Nii
	"Building A Knowledge-Based System With AGE,"
	submitted to Sixth IJCAI79, February 1979.
.skip 2
.apart
.group
	(158) <<HPP-79-4>
	H. Penny Nii, Nelleke Aiello
	"AGE (Attempt to Generalize):  A Knowledge-Based Program
	for Building Knowledge-Based Programs," submitted to 
	Sixth IJCAI79, February 1979.
.skip 2
.apart
.group
	(159) <<HPP-79-5> (working paper)
	L. Fagan, J. Kunz, E. Feigenbaum, CSD Stanford University
	J.J. Osborn from PMC, San Francisco
	"Knowledge Engineering for Dynamic Clinical Settings:
	Giving Advice In The Intensive Care Unit," submitted to
	Sixth IJCAI79, February 1979.
.skip 2
.apart
.group
	(161) <<HPP-79-7> (working paper)
	William van Melle,
	"A Domain-independent Production-rule System For Consultation
	Programs," submitted to Sixth IJCAI79, February 1979.
.skip 2
.apart
.group
	(162) <<HPP-79-8> (working paper)
	Alain Bonnet,
	"BAOBAB-2      Understanding Medical Jargon As If It Were A 
	Natural Language," submitted to Sixth IJCAI79, February 1979.
.skip 2
.apart
.group
	(163) <<HPP-79-9> (working paper)
	William J. Clancey,
	"Dialogue Management For Rule-based Tutorials," submitted to
	Sixth IJCAI79, February 1979.
.skip 2
.apart
.group
	(165) <<HPP-79-11> (working paper)
	A. Barr, W. Clancey, J. Bennett
	"Transfer of Expertise: A Theme of AI Research," April 1979.
.skip 2
.apart
.group
	(167) <<HPP-79-13>
	James S. Bennett, Robert S. Engelmore
	"SACON:  A Knowledge-Based Consultant For Structural Analysis,"
	submitted to Sixth IJCAI79, April 1979.
.skip 2
.apart
.group
	(169) <<HPP-79-15> (working paper)
	Douglas B. Lenat
	"Cognitive Economy,"
	June 1979.  Submitted to Sixth IJCAI79, August 1979.
.skip 2
.apart
.group
	(172) <<HPP-79-18>
	Larry M. Fagan, Edward H. Shortliffe, Bruce G. Buchanan
	"Computer-Based Medical Decision Making:  From MYCIN to VM,"
	to appear in Automedica, July 1979.
.skip 2
.apart
.group
	(174) <<HPP-79-20>
	Edward H. Shortliffe, Bruce G. Buchanan, Edward Feigenbaum,
	"Knowledge Engineering For Infectious Disease Therapy Selection"
	in Proceedings of the IEEE, Vol. 67, No. 9, September 1979.
.skip 2
.apart
.group
	(176)<<HPP-79-22>
	STAN-CS-79-756
	James S. Bennett, Bruce G. Buchanan, Paul R. Cohen 
	"Applications-oriented AI Research:  Sciences and Mathematics"
	to appear in Handbook of Artificial Intelligence, August 1979.
.skip 2
.apart
.group
	(177)<<HPP-79-23>
	STAN-CS-79-757
	Victor Ciesielski, James S. Bennett and Paul R. Cohen,
	"Applications-oriented AI Research:  Medicine"
	to appear in Handbook of Artificial Intelligence, August 1979.
.skip 2
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.group
	(180) <<HPP-79-26>
	Edward H. Shortliffe, M.D., Ph.D.
	"Clinical Knowledge Engineering:  The MYCIN Project"
	appeared in "Inference & Decision Making Processes in 
	Medicine," Proceedings of First International Workshop
	on Methodologies for Disease Control, August 25, 1979
	Tokyo Japan.
.skip 2
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.group
	(183) <<HPP-79-29>
	Peter E. Friedland
	"Knowledge-Based Experiment Design In Molecular Genetics,"
	Ph.D. dissertation, Stanford University, October 1979.
.skip 2
.apart
.group
	(157) <<HPP-80-2>
	STAN-CS-80-784
	Mark Jeffrey Stefik
	"Planning With Constraints," Ph.D. dissertation, 
	Stanford University, January 1980.
.skip 2
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