In mathematical logic, the notions of mathematical structure, language and proof themselves become the subject of mathematical investigation, and are treated as first class mathematical objects in their own right. Model theory is the branch of mathematical logic that is particularly concerned with the relationship between structure and language. It seeks to establish the limits of the expressiv...

Operator quantization of the WZNW theory for Lie algebra g with constrained affine Lie algebrâ h, h ⊂ g, is performed.The extended phase space and effective first class constraints are constructed which determine a class of g/h coset primary fields and currents. In a recent article [1] for generic g/h coset conformal field theory [2, 3] a class of Virasoro currents and primary fields was constr...

ion at the control level consists in defining new functions or procedures abstracting on theexisting ones. For example, in Scheme, expression such as: (define square (lambda (x) (* x x)))(define foo (lambda ...)) FIRST-CLASS CONSTRUCTS Scheme provides in particular a powerful and simple mem-ory model via first-class environments as well as a very flexi-ble and dynamic control mo...

A dynamic reasoning system (DRS) is an adaptation of a conventional formal logical system that explicitly portrays reasoning as a temporal activity, with each extralogical input to the system and each inference rule application being viewed as occurring at a distinct time step. Every DRS incorporates some well-defined logic together with a controller that serves to guide the reasoning process i...

The ET* algorithm is a complete evaluation strategy for Datalog programs, which are logic programs without function symbols. The ET* algorithm uses extension tables and depth-first iterative deepening to provide the evaluation of pure function-free logic programs as declarative specifications. Extension tables are a memo facility that the algorithm uses both to cut infinite derivation paths for...

The BankXX system models the process of perusing and gathering information for argument as a heuristic best-first search for relevant cases, theories, and other domain-specific information. As BankXX searches its heterogeneous and highly interconnected network of domain knowledge, information is incrementally analyzed and amalgamated into a dozen desirable ingredients for argument (called argum...

We present an environment for proving total correctness of mutual recursive functional programs. As usual, correctness is transformed into a set of first-order predicate logic formulae—verification conditions. As a distinctive feature of our method, these formulae are not only sufficient, but also necessary for the correctness. A specialized strategy for proving termination is developed. The de...

since the verbs of and have similar use and play an important role in arabic grammar, it was useful to study both and discuss about their functions. following the discussion we found that there is five different functions for :first, it is an imperfect verb, (that give the noun an nominative case and the comment an objective case) arabic grammar experts disagree if it has a verb function or a n...

purpose: the purpose of this study is to evaluate the effect of acceptance and commitment therapy for children with chronic pain (chact) on the function of 7 to 12 year-old children. thus, the basic problem of the current study is whether chact can improve the function level of 7 to 12 year-old children with chronic pain? method: according to the criteria of chronic pain, a number of children w...