The rest of the dissertation is organized as follows:
Chapter 2 focuses on the activity aspect of a UIA. It addresses issues associated with representing and reasoning about actions and their effects. Since reasoning about actions involves representing and reasoning about time, that topic is also examined in the same chapter. Chapter 2 also discusses some well known formalisms discussed in the literature to represent and reason about change, actions, and time.
Chapter 3 concentrates on the agency aspect of a UIA. It explores how an agent can plan its activities by representing different intentional notions and examines some formalisms that implement such notions.
Chapter 4 discusses Active logic--a time-sensitive and contradiction-tolerant logical framework that allows rich knowledge representation and flexible knowledge modification. It also gives a brief outline of Alma/Carne--the general purpose implementation language cum reasoner for Active logic based applications.
Chapter 5 formally specifies a theory of how an Active logic knowledge base changes and proves certain properties of an evolving Active logic knowledge base using the theory.
Chapter 6 introduces Active Logic For Agents (ALFA)--a unified theory for acting and agency which is based on Active logic and Alma/Carne and discusses how ALFA tackles some of the issues in representing and reasoning about time, actions and agency.
Chapter 7 examines the different aspects related to designing and specifying an agent architecture and provides a survey of some agent architectures.
Chapter 8 provides a meta-cognitive architecture (DIRECTOR--Domain Independent Reason-Enhanced Controller for Task Oriented Systems) for a universal interfacing agent which is based on ALFA.
Chapter 9 discusses how DIRECTOR architecture can be applied towards building a natural language based interface, ALFRED--Active Logic For Reason Enhanced Dialog. It also provides some preliminary results on the implementation of ALFRED.
Chapter 10 gives the conclusion and discusses future work.
The main technical contributions are presented in Chapters 5, 6, 8 and 9.