KEDAR-CABELLI@RED.RUTGERS.EDU (Smadar) (06/23/86)
III SEMINAR
Title: Advanced Planning Systems
Speaker: Chitoor V. Srinivasan
Date: Friday, June 27, 2:50 PM
Place: Hill Center, Room 705
Dr. Srinivasan, a professor in our department, will present his current
research in an informal talk. Here is his abstract:
A new planning technique for planning in "dynamic worlds" is
introduced in this talk. It develops plans using a method of
approximate reasoning and plan refinements over abstraction spaces,
and is based on a formalization of the problem solving approach which
Navy planners use to design Naval Operational Plans.
A dynamic world is one in which changes occur not only in the
properties associated with the objects that exist in the world, but
the set of objects existing in the world itself may change. As the
world changes some objects may get destroyed and others may get newly
created. It is a world in which reasoning about multiple actions
occuring simultaneously over intervals of time is necessary to do
planning. Also, knowledge needed to do planning in such worlds may be
only incompletely known. Existing planning systems do not consider
worlds of this kind.
In the new planning technique plans are viewed as hierarchies of
"behaviors" to be realized by actions that occur in a world.
Behaviors are properties (usually dynamic ones), which (a). remain
invariant while worlds themselves change as a result of actions
occurring in them, and (b). are needed for the success of one or more
of those actions, or are intrinsic properties of the worlds
themselves. Of course, a given behavior may be the result of several
actions occurring simultaneously. Thus for example, "an object will
continue to move in a straight line, unless disturbed by force" is a
general behavior of movements which is an intrinsic property of the
world we live in. "Goods transported will eventually appear in
neighborhoods progressively closer to destination" is a general
behavior of transportation actions.
This concept of behavior is formally defined here and a formal
action language is introduced to describe actions in terms of
"[preconditions, behaviors, functions]." It gives rise to a new
"modal action calculus" which is quite different from both "situation
calculus" and calculus of "dynamic logic." It is shown how this
concept of \fIbehavior\fR makes it possible to develop plans in
dynamic worlds through a process of successive plan refinements.