What makes industries believe in formal methods

The introduction of formal methods in the design and development departments of an industrial company has far reaching and long lasting consequences. In fact it changes the whole environment of methods, tools and skills that determine the design culture of that company. A decision to replace current design practice by formal methods, therefore, appears a vital one and is not lightly taken. The past has shown that efforts to introduce formal methods in industry has faced a lot of controversy and opposition at various hierarchical levels in companies, resulting in a marginal spread of such methods. This paper revisits the requirements for formal description techniques and identifies some critical success and inhibiting factors associated with the introduction of formal methods in the industrial practice. One of the inhibiting factors is the often encountered lack of appropriateness of the formal model to express and manipulate the design concerns that determine the world of the engineer. This factor motivated our research in the area of architectural and implementation design concepts. The last two sections of this paper report on some results of this research

Abstract Data Types in Event-B - An Application of Generic Instantiation

Integrating formal methods into industrial practice is a challenging task. Often, different kinds of expertise are required within the same development. On the one hand, there are domain engineers who have specific knowledge of the system under development. On the other hand, there are formal methods experts who have experience in rigorously specifying and reasoning about formal systems. Coordination between these groups is important for taking advantage of their expertise. In this paper, we describe our approach of using generic instantiation to facilitate this coordination. In particular, generic instantiation enables a separation of concerns between the different parties involved in developing formal systems.Comment: In Proceedings of DS-Event-B 2012: Workshop on the experience of and advances in developing dependable systems in Event-B, in conjunction with ICFEM 2012 - Kyoto, Japan, November 13, 201

Methods and models of next generation technology enhanced learning - White Paper

Our understanding of learning with technology is increasingly lagging behind technological advancements, such that it is no longer possible to fully understand learning with technologies without bringing together evidence from practice-based experiences and theoretical insight to inform research, design, policy and practice. Furthermore, whilst practical experiences and theoretical insights make significant contributions towards understanding learning with new technologies, the dynamic nature of learner practices and study contexts make it difficult to predict future requirements in terms of methods and models for next generation technology enhanced learning. We therefore require formal and comprehensive methods and models of learning with technology that accommodate theory and practice whilst allowing us to anticipate methodological innovations that capture future transitions and changes in learner practices and study contexts, in order to inform research, design, policy and practice. Workshop participants represented different communities of interest including research, design, evaluation and assessment. The overall objective was to anticipate methodological innovations in technology enhanced learning research and design over the next 5/10 years

Learning-assisted Theorem Proving with Millions of Lemmas

Large formal mathematical libraries consist of millions of atomic inference steps that give rise to a corresponding number of proved statements (lemmas). Analogously to the informal mathematical practice, only a tiny fraction of such statements is named and re-used in later proofs by formal mathematicians. In this work, we suggest and implement criteria defining the estimated usefulness of the HOL Light lemmas for proving further theorems. We use these criteria to mine the large inference graph of the lemmas in the HOL Light and Flyspeck libraries, adding up to millions of the best lemmas to the pool of statements that can be re-used in later proofs. We show that in combination with learning-based relevance filtering, such methods significantly strengthen automated theorem proving of new conjectures over large formal mathematical libraries such as Flyspeck.Comment: journal version of arXiv:1310.2797 (which was submitted to LPAR conference

How can I produce a digital video artefact to facilitate greater understanding among youth workers of their own learning-to-learn competence?

In Ireland, youth work is delivered largely in marginalised communities and through non-formal and informal learning methods. Youth workers operate in small isolated organisations without many of the resources and structures to improve practice that is afforded to larger formal educational establishments. Fundamental to youth work practice is the ability to identify and construct learning experiences for young people in non-traditional learning environments. It is therefore necessary for youth workers to develop a clear understanding of their own learning capacity in order to facilitate learning experiences for young people. In the course of this research, I attempted to use technology to enhance and support the awareness among youth workers of their own learning capacity by creating a digital video artifact that explores the concept – learning-to-learn. This study presents my understanding of the learning-to-learn competence as, I sought to improve my practice as a youth service manager and youth work trainer. This study was conducted using an action research approach. I designed and evaluated the digital media artifact – “Lenny’s Quest” in collaboration with staff and trainer colleagues in the course of two cycles of action research, and my research was critiqued and validated throughout this process

Transformation of UML Behavioral Diagrams to Support Software Model Checking

Unified Modeling Language (UML) is currently accepted as the standard for modeling (object-oriented) software, and its use is increasing in the aerospace industry. Verification and Validation of complex software developed according to UML is not trivial due to complexity of the software itself, and the several different UML models/diagrams that can be used to model behavior and structure of the software. This paper presents an approach to transform up to three different UML behavioral diagrams (sequence, behavioral state machines, and activity) into a single Transition System to support Model Checking of software developed in accordance with UML. In our approach, properties are formalized based on use case descriptions. The transformation is done for the NuSMV model checker, but we see the possibility in using other model checkers, such as SPIN. The main contribution of our work is the transformation of a non-formal language (UML) to a formal language (language of the NuSMV model checker) towards a greater adoption in practice of formal methods in software development.Comment: In Proceedings FESCA 2014, arXiv:1404.043

On Relation between Constraint Answer Set Programming and Satisfiability Modulo Theories

Constraint answer set programming is a promising research direction that integrates answer set programming with constraint processing. It is often informally related to the field of satisfiability modulo theories. Yet, the exact formal link is obscured as the terminology and concepts used in these two research areas differ. In this paper, we connect these two research areas by uncovering the precise formal relation between them. We believe that this work will booster the cross-fertilization of the theoretical foundations and the existing solving methods in both areas. As a step in this direction we provide a translation from constraint answer set programs with integer linear constraints to satisfiability modulo linear integer arithmetic that paves the way to utilizing modern satisfiability modulo theories solvers for computing answer sets of constraint answer set programs.Comment: Under consideration in Theory and Practice of Logic Programming (TPLP

Central Banks as Agents of Economic Development

In the last two decades, there has been a global sea change in the theory and practice of central banking. The currently dominant “best practice” approach to central banking consists of the following: (1) central bank independence (2) a focus on inflation fighting (including adopting formal “inflation targeting”) and (3) the use of indirect methods of monetary policy (i.e., short-term interest rates as opposed to direct methods such as credit ceilings). This paper argues that this neo-liberal approach to central banking is highly idiosyncratic in that, as a package, it is dramatically different from the historically dominant theory and practice of central banking, not only in the developing world, but, notably, in the now developed countries themselves. Throughout the early and recent history of central banking in the U.S., England, Europe, and elsewhere, financing governments, managing exchange rates, and supporting economic sectors by using “direct methods” of intervention have been among the most important tasks of central banking and, indeed, in many cases, were among the reasons for their existence. The neoliberal central bank policy package, then, is drastically out of step with the history and dominant practice of central banking throughout most of its history.