Preface Volume 36

AbstractThis volume constitutes the proceedings of the Third International Workshop on Rewriting Logic and its Applications.Following the successful first and second International Workshops on Rewriting Logic and its Applications, held in Asilomar (California) in September 1996 and in Pont-à-Mousson (France) in September 1998 respectively, the third workshop takes place in Kanazawa (Japan) in September 18, 19, 20 (Mon, Tue, Wed), 2000.Kanazawa is one of the most beautiful old towns in Japan. The workshop site (Kanazawa City Cultural Hall) is located just in the downtown of Kanazawa and major sightseeing spots are easily accessible on foot. This setting helps to make the workshop intimate, enjoyable, and productive.Rewriting logic is a natural semantic framework for concurrency, parallelism, and communication in computing, and for the specification of a wide range of systems and languages. It also has good properties as a logical framework for representing many varieties of logics. A growing number of research efforts exploring the foundations and applications of rewriting logic in all these directions are being carried out worldwide, and several languages based on rewriting logic such as CafeOBJ, ELAN, and Maude are being designed and implemented.The goal of WRLA2000 is to bring together researchers, from all over the world so that they can present their recent works, discuss future research directions, and exchange ideas. In addition to the presentations of research results, the program includes invited presentations and system demonstrations.Technical focuses of WRLA2000 are placed on such topics as secure protocol specifications and verification, future language features, rewriting for behavioral specifications, architecture for supporting system. We hope the discussions at the workshop help each participant to understand the current status and future issues of rewriting logic and relating fields.The workshop is supported by honest efforts of many people and organizations. The authors who submitted papers provide us the primary possibility of having interesting and productive workshop. The program committee members and external reviewers worked hard to review and select papers for presentation. These makes it possible for us to have an attractive program. The local arrangement and publicity chairs take care of running of the workshop, and let us enjoy the workshop under nice conditions. Ishikawa Prefecture, Kanazawa City, JAIST, SRA, and MRI support the workshop financially. We want to thank all of them for making it possible for us to have this productive workshop.Kanazawa, Japan, September 2000Kokichi Futatsug

Formalization and Verification of Behavioral Correctness of Dynamic Software Updates

AbstractDynamic Software Updating (DSU) is a technique of updating running software systems on-the-fly. Whereas there are some studies on the correctness of dynamic updating, they focus on how to deploy updates correctly at the code level, e.g., if procedures refer to the data of correct types. However, little attention has been paid to the correctness of the dynamic updating at the behavior level, e.g., if systems after being updated behave as expected, and if unexpected behaviors can never occur. We present an algebraic methodology of specifying dynamic updates and verifying their behavioral correctness by using off-the-shelf theorem proving and model checking tools. By theorem proving we can show that systems after being updated indeed satisfy their desired properties, and by model checking we can detect potential errors. Our methodology is general in that: (1) it can be applied to three updating models that are mainly used in current DSU systems; and (2) it is not restricted to dynamic updates for certain programming models

CafeOBJ: Logical Foundations and Methodologies

CafeOBJ is an executable industrial strength multi-logic algebraic specification language which is a modern successor of OBJ and incorporates several new algebraic specification paradigms. In this paper we survey its logical foundations and present some of its methodologies

Reducibility of operation symbols in term rewriting systems and its application to behavioral specifications

金沢大学理工研究域電子情報学系In this paper, we propose the notion of reducibility of symbols in term rewriting systems (TRSs). For a given algebraic specification, operation symbols can be classified on the basis of their denotations: the operation symbols for functions and those for constructors. In a model, each term constructed by using only constructors should denote an element, and functions are defined on sets formed by these elements. A term rewriting system provides operational semantics to an algebraic specification. Given a TRS, a term is called reducible if some rewrite rule can be applied to it. An irreducible term can be regarded as an answer in a sense. In this paper, we define the reducibility of operation symbols as follows: an operation symbol is reducible if any term containing the operation symbol is reducible. Non-trivial properties of context-sensitive rewriting, which is a simple restriction of rewriting, can be obtained by restricting the terms on the basis of variable occurrences, its sort, etc. We confirm the usefulness of the reducibility of operation symbols by applying them to behavioral specifications for proving the behavioral coherence property. © 2010 Elsevier Ltd. All rights reserved

Modeling, Specification, and Verification of QLOCK in CafeOBJ

6th VERITE : JAIST/TRUST-AIST/CVS joint workshop on VERIfication Technologyでの発表資料, 開催：3月12日～13日, 開催場所：JAIST 田町サテライトキャンパス2階多目的室

Generate & Check Methods for Invariant Verification in CafeOBJ

Effective coordination of inference (à la theorem proving) and search (à la model checking) is one of the most important and interesting research topics in formal methods. We have developed several techniques for coordinating inference and search for verification with proof scores in CafeOBJ. The generate & check methods proposed in this paper are recent developments for invariant verification of this kind. The methods are based on (1) state representations as sets of observers, and (2) systematic generation of finite state patterns which subsume all possible infinite states. This paper describes the generate & check methods and their theoretical foundation. The methods and theory are explained with a small but instructive example of mutual exclusion protocol. The explanation is intended to be self-contained, and includes necessary basics of the CafeOBJ language/system also.リサーチレポート（北陸先端科学技術大学院大学情報科学研究科

Generic proof scores for the generate & check method in CafeOBJ

Generic proof scores for the generate & check method in CafeOBJ are presented. The generic proof scores codify the generate & check method as parameterized modules in the CafeOBJ language independently of specific systems to which the method applies. Proof scores for a specific system can be obtained by substituting the parameter modules of the parameterized modules with the specification modules of the specific system.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Advances of Proof Scores in CafeOBJ

Critical flaws continue to exist at the level of domain, requirement, and/or design specification, and specification verification (i.e., to check whether a specification has desirable properties) is still one of the most important challenges in software/system engineering. CafeOBJ is an executable algebraic specification language system and domain/requirement/design engineers can write proof scores for improving quality of specifications by the specification verification. This paper describes advances of the proof scores for the specification verification in CafeOBJ.Comment: 44 pages, submitted to Science of Computer Programmin

Verifying Specifications with Proof Scores

1st VERITE : JAIST/TRUST-AIST/CVS joint workshop on VERIfication TEchnologyでの発表資料, 開催：2005年9月21日～22日, 開催場所：金沢市文化ホール3