Wumpus World

Giorgio Ingargiola, Associate Profession of Computer and Information Science at Temple University, has created the Wumpus World as an example of knowledge representation, reasoning, and planning to "introduce the Situation Calculus, the Frame Problem, and a variety of axioms." The axioms presented include Effect Axioms, Frame Axioms, and Successor-State Axioms. The lesson is followed by four questions which ask students to reflect and evaluate what they have just learned. This site is an excellent resource for calculus educators, and for students looking to further their calculus skills

Hierarchies and relations among data types

The aim of this report is to show that, within the limits of what we know how to do efficiently with computers, it is possible to design a system of types that, to a good degree, models the conceptual hierarchies that we use in our everyday discourse. A method is presented for representing sets of objects by types and for representing relations among objects by relations among types. In the definition of types we can use variables (called formal variables) that range on types, and methods are provided for binding such variables to particular types. Types are either primitive, or formal variables, or obtained from types by the application of definitional operators. Relations are established among types to express that their instances have the same physial representation, or to express, possibly with additional requirements, that the set of instances of a type is a subset of the set of instances of another. These relations are used to assure that assignments and procedure calls preserve the membership of objects to the sets that are denoted by their types. By the use of formal variables we achieve the ability to abstract, in particular contexts, from details of objects

Finding Optimal Demand Paging Algorithms

A cost is defined for demand paging algorithms with respect to a formal stochastic model of program behavior. This cost is shown to exist under rather general assumptions, and a computational procedure is given which makes it possible to determine the optimal cost and optimal policy for moderate size programs, when the formal model is known and not time dependent. In this latter case it is shown that these computational procedures may be extended to larger programs to obtain arbitrarily close approximations to their optimal policies. In previous models either unwarranted information is assumed beyond the formal model, or the complete stochastic nature of the model is not taken into account

Reduction Algorithm for Zero-One Single Knapsack Problems

A simple algorithm is described for the reduction of 0-1 single knapsack problems to significantly smaller problems. The time required by the reduction algorithm is proportional to the number of variables. When used in conjunction with available algorithms for knapsack problems it substantially reduces total time and space requirements.