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This course covers AI theories, program architecture, search algorithms, state-space modeling, and abstracting problem states in Java. Learn about uninformed and informed search algorithms, abstraction mechanisms, and design patterns. Discover how to model problem structures graphically and implement search strategies. Explore generality, reuse, and the interaction between AI theory and program architecture. Gain insights into DFS, BFS, best-first search, heuristic ranks, and the separation of representation and control. Put the framework to use by defining problem states efficiently and implementing searches effectively in Java.
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CSCE 580Artificial IntelligenceProblem Spaces and Search Fall 2011 Jingsong Wang wang82@engr.sc.edu
Abstraction and Generality in Java • The Interaction between AI theory and program architecture • Implementation of search strategies • Generality and reuse • Abstraction mechanisms and design patterns
Search Algorithms • Uninformed algorithms: • Depth-first search (DFS) • Breadth-first search (BFS) • … • Informed algorithms • Best-first search • …
Search Algorithms • Model the structure of a problem graphically as a state—space • Elements defining a state-space: • A formal representation of possible states of a problem solution • Operators for generating new states from a given state • Some way of recognizing a goal state • A starting state of the problem, represented as the root of the graph
Search Algorithms • DFS – stack • BFS – queue • Best-first search – priority queue • Heuristic rank • sorted
Abstracting Problem States • The separation of representation and control • States and search engines • Goal: to define an abstract representation of problems states that supports the general search algorithm and can be easily specialized through the mechanism of class inheritance
Abstracting Problem States • Abstract class
Abstracting Problem States • Interface
Abstracting Problem States • Java’s generic • Collection-Type<Element-Type>
Traversing the Problem Space • Implementation of search itself • Define the list of states and the mechanisms for moving through them in search
Putting the Framework to Use • See the code in Eclipse