Preface These note s expan d te n lecture s give n a t a regiona l conferenc e i n Lincoln , Nebraska. Th e objective is to describe the idea behind a broad variety of topics in a brief volume. Th e conference assemble d a wide variety o f scientists: pur e mathematicians o n one hand an d engineer s on the other. Consequentl y on e of the constraints o n thes e note s wa s tha t the y stak e ou t a middl e groun d an d make th e extreme s accessibl e t o mos t conferenc e participants . However , thes e extremes provide d a distinctiv e flavor which i s missin g fro m thes e notes . I n particular talk s by other participants gav e substantial practic e i n applying th e results of Chapter 5 and Chapter 8 to control problems. This volume splits into four parts which are nearly independent. A n approxi- mate description of what you must have read in order to read a particular chapter is: -tU-HZl Part I Part I -*GD SKETCHY NO PROOFS (proofs use 5)

Purchased from American Mathematical Society for the exclusive use of nofirst nolast (email unknown) Copyright 1987 American Mathematical Society. Duplication prohibited. Please report unauthorized use to cust-serv@ams.org. Thank You! Your purchase supports the AMS' mission, programs, and services for the mathematical community.