Resilient self-debugging software protection

Debuggers are a popular reverse engineering and tampering tool. Self-debugging is an effective technique for applications to defend themselves against hostile debuggers. In penetration tests on state-of-the-art self-debugging, we observed several opportunities through which it could be attacked, however. We therefore improved upon the existing technique, making it more resilient by introducing reciprocal debugging and making the transfers of control between protected application and self-debugger more stealthy. This paper presents the improved self-debugging design, and details our research efforts into realizing reciprocal debugging. In our evaluation we show that the improved design is significantly harder for attackers to defeat

View-based textual modelling

This work introduces the FURCAS approach, a framework for view-based textual modelling. FURCAS includes means that allow software language engineers to define partial and overlapping textual modelling languages. Furthermore, FURCAS provides an incremental update approach that enables modellers to work with multiple views on the same underlying model. The approach is validated against a set of formal requirements, as well as several industrial case studies showing its practical applicability

Implicit Incremental Model Analyses and Transformations

When models of a system change, analyses based on them have to be reevaluated in order for the results to stay meaningful. In many cases, the time to get updated analysis results is critical. This thesis proposes multiple, combinable approaches and a new formalism based on category theory for implicitly incremental model analyses and transformations. The advantages of the implementation are validated using seven case studies, partially drawn from the Transformation Tool Contest (TTC)

Some of the challenges and experiences of formal education in a Mobile-Centric Society (MCS)

The aim of the paper is to describe some of the challenges faced by schools, or by formal education in general, as a consequence of today's mobile-centric society (henceforth MCS), the term we will use to denote the new, networked learning ecology that has arisen from the massive penetration of digital media in everyday life. After revisiting some of the ideas of McLuhan and Vygotsky in the light of this new technological scenario, we describe five traits of the MCS and the challenges - illustrated through educational practices - that we believe schools will face if they wish to preserve their function of individualization and socialization. We believe that despite the emergence of the MCS, the main function of the school is still to provide the "box of tools" (a set of psychological instruments, such as reading, writing, mathematical notation, digital literacy, etc.) that enables people to develop their learning skills and life projects and to become part of communities and groups. However, the complexity and mobility of the new learning environments means that the position held by schools needs to be re-evaluated in the face of the informal learning paths and experiences - both online and offline - to which learners now have access. We also need to re-evaluate the meaning of the school itself as an institution and the model of learner it should be training

Functional Analysis of the Microgrid Concept Applied to Case Studies of the Sundom Smart Grid

The operation of microgrids is a complex task because it involves several stakeholders and controlling a large number of different active and intelligent resources or devices. Management functions, such as frequency control or islanding, are defined in the microgrid concept, but depending on the application, some functions may not be needed. In order to analyze the required functions for network operation and visualize the interactions between the actors operating a particular microgrid, a comprehensive use case analysis is needed. This paper presents the use case modelling method applied for microgrid management from an abstract or concept level to a more practical level. By utilizing case studies, the potential entities can be detected where the development or improvement of practical solutions is necessary. The use case analysis has been conducted from top-down until test use cases by real-time simulation models. Test use cases are applied to a real distribution network model, Sundom Smart Grid, with measurement data and newly developed controllers.. The functional analysis provides valuable results when studying several microgrid functions operating in parallel and affecting each other. For example, as shown in this paper, ancillary services provided by an active customer may mean that both the active power and reactive power from customer premises are controlled at the same time by different stakeholders.© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).fi=vertaisarvioitu|en=peerReviewed

Mathematical Foundations for a Compositional Account of the Bayesian Brain

This dissertation reports some first steps towards a compositional account of active inference and the Bayesian brain. Specifically, we use the tools of contemporary applied category theory to supply functorial semantics for approximate inference. To do so, we define on the `syntactic' side the new notion of Bayesian lens and show that Bayesian updating composes according to the compositional lens pattern. Using Bayesian lenses, and inspired by compositional game theory, we define fibrations of statistical games and classify various problems of statistical inference as corresponding sections: the chain rule of the relative entropy is formalized as a strict section, while maximum likelihood estimation and the free energy give lax sections. In the process, we introduce a new notion of `copy-composition'. On the `semantic' side, we present a new formalization of general open dynamical systems (particularly: deterministic, stochastic, and random; and discrete- and continuous-time) as certain coalgebras of polynomial functors, which we show collect into monoidal opindexed categories (or, alternatively, into algebras for multicategories of generalized polynomial functors). We use these opindexed categories to define monoidal bicategories of cilia: dynamical systems which control lenses, and which supply the target for our functorial semantics. Accordingly, we construct functors which explain the bidirectional compositional structure of predictive coding neural circuits under the free energy principle, thereby giving a formal mathematical underpinning to the bidirectionality observed in the cortex. Along the way, we explain how to compose rate-coded neural circuits using an algebra for a multicategory of linear circuit diagrams, showing subsequently that this is subsumed by lenses and polynomial functors.Comment: DPhil thesis; as submitted. Main change from v1: improved treatment of statistical games. A number of errors also fixed, and some presentation improved. Comments most welcom