LOTOS Symbolic Semantics in Maude

We present a formal tool where LOTOS specifications without restrictions in their data types can be executed. The reflective feature of rewriting logic and the metalanguage capabilities of Maude make it possible to implement the whole tool in the same semantic framework, and have allowed us to implement the LOTOS semantics and to build an entire environment with parsing, pretty printing, and input/output processing of LOTOS specifications

Executable Structural Operational Semantics in Maude

This paper describes in detail how to bridge the gap between theory and practice when implementing in Maude structural operational semantics described in rewriting logic, where transitions become rewrites and inference rules become conditional rewrite rules with rewrites in the conditions, as made possible by the new features in Maude 2.0. We validate this technique using it in several case studies: a functional language Fpl (evaluation and computation semantics, including an abstract machine), imperative languages WhileL (evaluation and computation semantics) and GuardL with nondeterminism (computation semantics), Kahn’s functional language Mini-ML (evaluation or natural semantics), Milner’s CCS (with strong and weak transitions), and Full LOTOS (including ACT ONE data type specifications). In addition, on top of CCS we develop an implementation of the Hennessy-Milner modal logic for describing local capabilities of processes, and for LOTOS we build an entire tool where Full LOTOS specifications can be entered and executed (without user knowledge of the underlying implementation of the semantics). We also compare this method based on transitions as rewrites with another one based on transitions as judgements

Modular specification in rewriting logic (extended version)

Our aim is to bring modularity to system specification in rewriting logic. Modularity here is in the sense of decomposing a system into its functional components, coding the specification for each component as a separate system, and then assembling them back. Rewriting logic is well suited for the specification of concurrent and non-deterministic systems but, up to now, modularity could hardly be addressed within it. The base of our proposal is the operation that we call synchronous composition. We discuss the reasons and implications of our proposal, and formalize it for rewriting logic and also for transition structures, to be used as semantics. To show the power of our approach, we include a few small but realistic examples and a larger example on cached computer architecture

A Declarative Debugger for Maude Specifications: User Guide

We show in this guide how to use our declarative debugger for Maude specifications. Declarative debugging is a semi-automatic technique that starts from a computation considered incorrect by the user (error symptom) and locates a program fragment responsible for the error by asking questions to an external oracle, which is usually the user. In our case the debugging tree is obtained from a proof tree in a suitable semantic calculus; more concretely, we abbreviate the proof trees obtained from this calculus in order to ease and shorten the debugging process while preserving the correctness and completeness of the technique. We present the main features of our tool, what is assumed about the modules introduced by the user, the list of available commands, and the kinds of questions used during the debugging process. Then, we use several examples to illustrate how to use the debugger. We refer the interested reader to the webpage http://maude.sip.ucm.es/debugging, where these and other examples can be found together with more information about the theory underlying the debugger, its implementation and the Maude source files

Emotional and non-emotional pathways to impulsive behavior and addiction

The research presented here has been funded by grants from the Ministerio de Ciencia e Innovación, MICINN (Spain), for Ana Torres/José C. Perales (ref. # PSI2009-13133), and Andrés Catena/Antonio Maldonado (ref. # PSI2009-12217); by a Junta de Andalucía (Spain) grant (ref. # PB09-SEJ4752) for Antonio Cándido: and by a RETICS (Redes Temáticas de Investigación Cooperativa en Salud) subprogramme grant (Ref. # RD12/0028/0017) from the Ministerio de Sanidad, Servicios Sociales e Igualdad (Spain), for José C. Perales/Antonio Verdejo-García.Impulsivity is tightly linked to addiction. However, there are several pathways by means of which impulsive individuals are more prone to become addicts, or to suffer an addiction more intensely and for a longer period. One of those pathways involves an inadequate appraisal or regulation of positive and negative emotions, leading to lack of control over hazardous behaviors, and inappropriate decisions. In the present work, we assessed cocaine-dependent individuals (CDI; n = 20), pathological gamblers (PG; n = 21), and healthy controls (HC; n = 23) in trait impulsivity measures (UPPS-P model's dimensions), and decision-making tasks (Go/No-go; delay-discounting task). During the Go/No-go task, electroencephalographic (EEG) activity was recorded, and Go/No-go stimuli-evoked potentials (ERP) were extracted. Theory-driven ERP analyses focused on the No-go > Go difference in the N2 ERP. Our results show that negative urgency is one of the several psychological features that distinguish addicts from HC. Nevertheless, among the dimensions of trait impulsivity, negative urgency is unique at independently covarying with gambling over-pathologization in the PG sample. Cocaine-dependent individuals performed more poorly than gamblers in the Go/No-go task, and showed abnormal Go/No-go stimuli-evoked potentials. The difference between the No-go stimulus-evoked N2, and the Go one was attenuated by severity and intensity of chronic cocaine use. Emotional dimensions of impulsivity, however, did not influence Go/No-go performance.Ministerio de Ciencia e Innovación, MICINN (Spain), for Ana Torres/José C. Perales (ref. # PSI2009-13133), and Andrés Catena/Antonio Maldonado (ref. # PSI2009-12217)Junta de Andalucía (Spain) grant (ref. # PB09-SEJ4752) for Antonio CándidoRETICS (Redes Temáticas de Investigación Cooperativa en Salud) subprogramme grant (Ref. # RD12/0028/0017) from the Ministerio de Sanidad, Servicios Sociales e Igualdad (Spain), for José C. Perales/Antonio Verdejo-García

Model checking strategy-controlled rewriting systems (extended version)

Strategies are widespread in Computer Science. In the domain of reduction and rewriting systems, strategies are studied as recipes to restrict and control reduction steps and rule applications, which are intimately local, in a derivation-global sense. This idea has been exploited by various tools and rewriting-based specification languages, where strategies are an additional specification layer. Systems so described need to be analyzed too. This article discusses model checking of systems controlled by strategies and presents a working strategy-aware LTL model checker for the Maude specification language, based on rewriting logic, and its strategy language. This extended version includes the proofs of the propositions in the conference paper, and a complete description of the small-step operational semantics used to define model checking for the Maude strategy language

Añadiendo mecanismos de ayuda en un juez on-line automático para soporte a mentorías académicas

Todos los jueces en línea, incluído en sus inicios ¡Acepta el reto! (https://www.aceptaelreto.com) desarrollado por profesores de la UCM, adolecen de un problema de realimentación al usuario: cuando el visitante hace un envío incorrecto el sistema no es capaz de dar información específica del error. El documento es la memoria final de un Proyecto de Innovación y Mejora de la Calidad Docente (PIMCD) de 2017/2018 en el que se puso en marcha un sistema de pistas en el juez

La gamificación en la educación universitaria: aplicación a asignaturas de programación

Informe sobre la experiencia de aplicar técnicas de gamificación en la asignatura “Estructura de Datos y Algoritmos”, obligatoria de 2º curso en los grados impartidos en la Facultad de Informática de la UCM

A tool for Full LOTOS in Maude

We describe a formal tool based on a symbolic semantics for Full LOTOS, where speci cations without restrictions in their data types can be executed. The re ective feature of rewriting logic and the metalanguage capabilities of Maude make it possible to implement the whole tool in the same semantic framework, and have allowed us to implement the LOTOS operational semantics, to integrate it with ACT ONE speci cations, and to build an entire environment with parsing, pretty printing, and input/output processing of LOTOS speci cations. Our aim has been to implement a formal tool that can be used by everyone without knowledge of the concrete implementation, but where the semantics representation is at so high level that can be understood and modi ed by everyone that knows about operational semantics

Cardelli’s Challenge in Mobile Maude: A Conference Reviewing System

A useful way of presenting a new language is by means of complete examples that show the language features in action. In this paper we do so for the Mobile Maude language, an extension of Maude that suports mobile computation. We implement an ambitious wide area application, namely a conference reviewing system, an example described by Cardelli as a challenge for any wide area language to demonstrate its usability