46716843
Induction, Abduction, and Consequence-Finding
This paper shows a sound and complete method for inverse entailment in inductive logic programming. We show that inverse entailment can be computed with a resolution method for consequence-finding. In comparison with previous work, induction via consequence-finding is sound and complete for finding hypotheses from full clausal theories, and can be used for inducing not only definite clauses but also non-Horn clauses and integrity constraints. We also compare induction and abduction from the viewpoint of consequence-finding, and clarify the relationship and difference between the two.
39318479
Extended Logic Programs with Default Assumptions
23434786
Conditional Answer Computation in SOL as Speculative Computation in Multi-Agent Environments
Abstract In this paper, we study speculative computation in a master-slave multi-agent system where reply messages sent from slave agents to a master are always tentative and may change from time to time. In this system, default values used in speculative computation are only partially determined in advance. Inoue et al. [8] formalized speculative computation in such an environment with tentative replies, using the framework of a first-order consequence-finding procedure SOL with the well-known answer literal method. We shall further refine the SOL calculus, using conditional answer computation and skip-preference in SOL. The conditional answer format has an great advantage of explicitly representing how a conclusion depends on tentative replies and defaults, both of which are used to derive the conclusion. The dependency representation is significantly important to avoid unnecessary recomputation of tentative conclusions. The skip-preference has the great ability of preventing irrational/redundant derivations.
43364652
Effective SAT Planning by Speculative Computation
In recent years, SAT planning has been studied actively. In this paper, we propose a new method, called speculative computation, for accelerating the SAT planning. A SATplanner firstly translates a planning problem into the boolean satisfiability (SAT) problem, and secondly solves it by a general-purpose SAT solver. Blackbox [1], which is one of the fastest planning systems in the world, is based on this approach. Given a planning problem, Blackbox performs the following; (i) assumes that the plan length is i (initially, i = 1), (ii) translates the planning problem into a SAT problem P i, and (iii) solves P i. If P i is found to be satisfiable, the Blackbox extracts a plan of length i from the truth assignment satisfying P i. When P i is unsatisfiable, the planner increases the plan length to be i + 1, and returns to (i).
16797379
Transforming Abductive Logic Programs to Disjunctive Programs
A new xpoint semantics for abductive logic programs is provided, in which the generalized stable models of an abductive program are characterized as the xpoint of a disjunctive program obtained by a suitable program transformation. In the transformation, both negative hypotheses through negation as failure and positive hypotheses from the abducibles are dealt with uniformly. This characterization allows us to have a parallel bottomup model generation procedure for computing abductive explanations from arbitrary (range-restricted and function-free) general, extended, and disjunctive programs with integrity constraints.
18018809
Consequence-Finding Based on Ordered Linear Resolution
Since linear resolution with clause ordering is incomplete for consequence-finding, it has been used mainly for proof-finding. In this paper, we re-evaluate consequence-finding. Firstly, consequence-finding is generalized to the problem in which only interesting clauses having a certain property (called characteristic clauses) should be found. Then, we show how adding a skip rule to ordered linear resolution makes it complete for consequence-finding in this general sense. Compared with set-of-support resolution, the proposed method generates fewer clauses to find such a subset of consequences. In the propositional case, this is an elegant tool for computing the prime implicants/implicates. The importance of the results lies in their applicability to a wide class of AI problems including procedures for nonmonotonic and abductive reasoning and truth maintenance systems.
10307213
Very-Large Scale Code Clone Analysis and Visualization of Open Source Programs Using Distributed CCFinder: D-CCFinder
The increasing performance-price ratio of computer hardware makes possible to explore a distributed approach at code clone analysis. This paper presents D-CCFinder, a distributed approach at large-scale code clone analysis. D-CCFinder has been implemented with 80 PC workstations in our student laboratory, and a vast collection of open source software with about 400 million lines in total has been analyzed with it in about 2 days. The result has been visualized as a scatter plot, which showed the presence of frequently used code as easy recognizable patterns. Also, D-CCFinder has been used to analyze a single software system against the whole collection in order to explore the presence of code imported from open source software.
17773922
A formal adaption method for process descriptions
Requirement to describing software development processes in formal manners has been increased, and demand for altering and tailoring the process descriptions has been emerged. In this paper, we propose a functional language PDL (Process Description Language), designed to describe various development processes under a certain environment. To create and modify the PDL scripts easily and correctly, we propose a method of stepwise refinement from abstract scripts into concrete scripts. By this method, the abstract definitions of software process flow and product flow initially given as function definitions irk PDL, are transformed into the concrete definitions of the tool activations, message displays, and so on. We also discuss an architecture design of a software development environment (Adaptable Software Development Environment), which can be adapted in many ways for designer's requirements.
6398416
Analysis of the Linux Kernel Evolution Using Code Clone Coverage
Most studies of the evolution of software systems are based on the comparison of simple software metrics. In this paper, we present our preliminary investigation of the evolution of the Linux kernel using code-clone analysis and the code-clone coverage metrics. We examined 136 versions of the stable Linux kernel using a distributed extension of the code clone detection tool CCFinder. The result is shown as a heat map.