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This paper presents an approach to P system verification using the Spin model checker. It proposes a P system implementation in PROMELA, the modeling language accepted by SPIN. It also provides the theoretical background for transforming the temporal logic properties expressed for the P system into properties of the executable implementation. Furthermore, a comparison between P systems verification using SPIN and NUSMV is realized. The results obtained show that the PROMELA implementation is more adequate, especially for verifying more complex models, such as P systems that model ecosystems. [ABSTRACT FROM AUTHOR]

The Larch family of specification languages supports a two-tiered definitional approach to specification. Each specification has components written in two languages: one designed for a specific programming language and another independent of any programming language. The former are called Larch interface languages, and the latter the Larch Shared Language (LSL). The Larch style of specification emphasizes brevity and clarity rather than executability. To make it possible to test specifications without executing or implementing them, Larch permits specifiers to make claims about logical properties of specifications and to check these claims at specification time. Since these claims are undecidable in the general case, it is impossible to build a tool that will automatically certify claims about arbitrary specifications. However, it is feasible to build tools that assist specifiers in checking claims as they debug specifications. This paper describes the checkability designed into LSL and discusses two tools that help perform the checking. This paper is a revised and expanded version of a paper presented at the April 1990 IFIP Working Conference on Programming Concepts and Methods [7]. [ABSTRACT FROM AUTHOR]

A language L is called the orthogonal shuffle of the language L1 with the language L2, along the trajectory set T if every word in L is uniquely obtained as the shuffle between a word in L1, a word in L2 along a trajectory word in T. In this paper we investigate properties of the orthogonal shuffle on trajectories, as well as several types of language equations using this language operation. As a corollary, we obtain several properties of orthogonal catenation, orthogonal literal shuffle and orthogonal insertion. [ABSTRACT FROM AUTHOR]

This paper generalizes the concept of blind multicounter languages to infinite words. We introduce two different acceptance modes of blind multicounter machines on ω-words, called synchrononous and asynchronous acceptance. These acceptance modes are compared with each other and with families of ω-languages of the form L = ∪_{1⩽i⩽k}U_iV^ω_i, where U_i, V_i are finitary blind multicounter languages. [ABSTRACT FROM AUTHOR]

This paper is an introduction to the main features of ALGOL 68, emphasizing the novel features not found in many other programming languages. The topics, data types (modes), type conversion (coercion), generalized expressions (units), procedures, operators, the standard prelude, and input/output, form the basis of the paper. The approach is informal, relying heavily on many short examples. The paper applies to the Revised Report, published in 1975, rather than to the original report, published in 1969. [ABSTRACT FROM AUTHOR]

Abstract: The technique of determining a generating function for an unambiguous context-free language is known as the Schützenberger methodology. For regular languages, Elena Barcucci et al. proposed an approach for inverting this methodology based on Soittola’s theorem. This idea allows a combinatorial interpretation (by means of a regular language) of certain positive integer sequences that are defined by C-finite recurrences. In this paper we present a Maple implementation of this inverse methodology and describe various applications. We give a short introduction to the underlying theory, i.e., the question of deciding -rationality. In addition, some aspects and problems concerning the implementation are discussed; some examples from combinatorics illustrate its applicability. [Copyright &y& Elsevier]

The languages C and PASCAL are growing in popularity, particularly among programmers of small computers. In this paper we summarize and compare the two languages covering their design philosophies, their handling of data types, the programming facilities they provide, the impact of these facilities on the quality of programs, and how useful the facilities are for programming in a variety of application domains. [ABSTRACT FROM AUTHOR]

Moggi's Computational Monads and Power et al.'s equivalent notion of Freyd category have captured a large range of computational effects present in programming languages. Examples include non-termination, non-determinism, exceptions, continuations, side effects and input/output. We present generalisations of both computational monads and Freyd categories, which we call parameterised monads and parameterised Freyd categories, that also capture computational effects with parameters. Examples of such are composable continuations, side effects where the type of the state varies and input/output where the range of inputs and outputs varies. By considering structured parameterisation also, we extend the range of effects to cover separated side effects and multiple independent streams of I/O. We also present two typed λ-calculi that soundly and completely model our categorical definitions -- with and without symmetric monoidal parameterisation -- and act as prototypical languages with parameterised effects. [ABSTRACT FROM AUTHOR]

In the last years, there were made efforts for delineation of a stabile and unitary frame, where the problems of logical parallel processing must find solutions at least at the level of imperative languages. The results obtained by now are not at the level of the made efforts. This pa-per wants to be a little contribution at these efforts. We propose a overview in parallel programming, parallel execution and collaborative systems. [ABSTRACT FROM AUTHOR]

A regular component is either autodense or anti-autodense. Characterizations of a regular component being a pure autodense language and being a pure autodense code are obtained. A relationship between intercodes and anti-autodense languages is that for an intercode L of index m, L n is an anti-autodense language for every n > m. [ABSTRACT FROM AUTHOR]

We introduce a new variant of membrane systems where the rules are directly assigned to membranes and, moreover, every membrane carries an energy value that can be changed during a computation by objects passing through the membrane. The result of a successful computation is considered to be the distribution of energy values carried by the membranes. We show that for systems working in the sequential mode with a kind of priority relation on the rules we already obtain universal computational power. When omitting the priority relation, we obtain a characterization of the family of Parikh sets of languages generated by context-free matrix grammars. On the other hand, when using the maximally parallel mode, we do not need a priority relation to obtain computational completeness. Finally, we introduce the corresponding model of tissue P systems with energy assigned to the membrane of each cell and objects moving from one cell to another one in the environment as well as being able to change the energy of a cell when entering or leaving the cell. In each derivation step, only one object may pass through the membrane of each cell. When using priorities on the rules in the sequential mode (where in each derivation step only one cell is affected) as well as without priorities in the maximally parallel mode (where in each derivation step all cells possible are affected) we again obtain computational completeness, whereas without priorities on the rules in the sequential mode we only get a characterization of the family of Parikh sets of languages generated by context-free matrix grammars. [ABSTRACT FROM AUTHOR]

The process of engineering software-intensive systems that comply with their Certification and Accreditation (C&A) requirements involves many critical decision-making activities for the related stakeholders. Considering the exhaustive nature of C&A activities together with the complexity of software-intensive systems, effective decision making relies heavily on the ways to understand and structure the problem domain concepts concerning decision points for interpretation, applicability, scope, evaluation, and impact of the enforced C&A requirements. These decision points are further complicated by natural language specifications of inherently non-functional C&A requirements scattered across multiple regulatory documents with complex interdependencies at different levels of abstractions in the organizational hierarchy, which often result in subjective interpretations and non-standard implementations of the C&A process. To address these issues, we define a systematic methodology using novel techniques from software Requirements Engineering (RE) and knowledge engineering for understanding and structuring the problem domain concepts based on a uniform representation format that promotes common understanding among stakeholders. Specifically, we use advanced ontological engineering techniques driven by theoretical RE foundations to systematically elicit, model, understand, and analyze problem domain concepts concerning significant and difficult decision points throughout the C&A process. We demonstrate the appropriateness of our methodology in creating decision support problem domain ontology using several examples derived from our experiences on automating the Department of Defense Information Technology Security C&A Process (DITSCAP). [ABSTRACT FROM AUTHOR]