			 DRS(Defeasible Reasoning System)
										
1.  Overview

DRS is a tool that provides a function of generating argument and function of
selecting argument of HELIC-II, by user's keyboard inputs only.

Details of this functions are as follows.

[Generating argument]

This function makes a proof tree which indicates a conclusion(goal) as an
argument when the facts and rules are already given and then a conclusion is
given.

There are two kinds of rules; usual rules(RBR rules) and CBR rules.  CBR rule
has the characteristic of being applied after generalization.

[Selecting argument]

This function is realized by defeasible reasoning, that is one of nonmonotonic
reasoning.

Defeasible reasoning generates an argument of a given conclusion and its counter
argument.  It then determines the type of argument from the TopRule relation
(refer to appendix for details), the priority relation of rules between the
argument and its counter argument, and the type of its counter argument.

Types of arguments are as follows:

* justify
	Refutes all counter arguments.
* defeated
	Refuted by at least one of its counter argument.
* plausible
	Unrelated or refutes to a counter argument.

Refutes,refuted, and unrelated are determined by the TopRule relation for the
counter argument, and the type of the counter argument.

For details, refer to HELIC-II language manual.

2.execution environment

Confirmed to run on following environments in execution and installation.

(1) hardware
	(a) machine
		Sun sparcStatiion 10
	(b) memory
		more than 32MB
	(c) harddisk
		more than 40MB

(2) software
	(a) OS
		SunOS 4.1.3
	(b) C compiler
		gcc-2.6.2
	(c) KLIC(KLIC is IFS)
		more than version1.7
	(d) environment of Japanese
		Needs following either gcc library or header file,
		when installs DRS that use knowlede source(rule,type)
		to include Japanese.
		
		* library
			libfl.a
		* header file
			euc.h

3.installation

Please refer to DRS install manual(file name: INSTALL).
