Abstract
The transition to circular business models poses significant challenges, particularly for Small and Medium Enterprises (SMEs). These challenges arise from different perspectives. Strategic alignment and technological barriers are just two of them. This paper aims to explore how Industry 4.0 technologies and Enterprise Architectures can facilitate the implementation of circular business models. By analyzing their role in overcoming key obstacles, the study explores the potential of these technologies in driving sustainable business transformation. The findings indicate that while integrating circularity into business practices remains complex, Enterprise Architectures, through the adoption of Industry 4.0 technologies, can mitigate some barriers. Ultimately, the synergy between technological innovation and circular business models can accelerate the shift towards sustainability.

Abstract
Kleene algebras (KA) and Kleene algebras with tests (KAT) provide an algebraic framework to capture the behavior of conventional programming constructs. This paper explores a broader understanding of these structures, in order to enable the expression of programs and tests yielding vague or inconsistent outcomes. Within this context, we introduce the concept of a paraconsistent Kleene Algebra with tests (PKAT), capable of capturing vague and contradictory computations. Finally, to establish the semantics of such a structure, we introduce two algebras, SetP(T) and RelP(K,T), parametric on a class of twisted structures K and T. We believe this sort of structures, for their huge flexibility, have an interesting application potential.

Abstract
The main aim of this chapter is to explore the role of social media in the internationalization of business-to-business (B2B) companies, addressing a remaining gap in the literature. It includes a qualitative study, where data from semi-structured interviews was subject to thematic content analysis. The study found that social media acts as a facilitator of internationalization in the B2B setting. While social media alone does not determine the success of internationalization efforts, it has become an essential tool for firms seeking to engage with global markets and maintain a competitive edge. The study provides relevant insights for managers, recommending that businesses should track social media performance to understand its impact on internationalization efforts and adjust strategies accordingly. © 2025 Elsevier B.V., All rights reserved.

Abstract

Abstract
This paper presents a current estimation approach for four-phase Switched Reluctance Machines (SRMs) using only two current sensors. The power converter structure under consideration is an asymmetric half-bridge topology in which the upper switch is shared by two phases, resulting in a reduced number of measurable current paths. Two current estimation methods are developed and compared in a simulation environment. Both techniques aim to reconstruct the instantaneous phase currents to enable advanced torque and flux control strategies without the need for individual current sensors on each phase. The effectiveness of each method is validated through Matlab/Simulink simulations, and their performance is assessed under different operating scenarios.

Abstract
This present study examines the accessibility of European universities for students with disabilities, drawing on two data sources. The first data source, a desk research, examined publicly available information on the websites of 171 universities from 38 European countries. In this desk research, we performed an audit of university websites and analysed the availability of accessibility services. The second data source, an online survey was distributed to accessibility/diversity offices at 124 universities, with full responses received from seven institutions in various European countries. The study reveals a significant disparity in accessibility resources and support services across European regions. Universities in Northern Europe, the UK, and Ireland exhibit a higher level of accessibility, both in terms of website accessibility and the availability of comprehensive support services. In contrast, universities in Eastern and Southern Europe often lag behind, with less visible accessibility information on websites, limited resources for accessibility offices, and fewer assistive technologies available to students. The most common accessibility issues identified on university websites are ambiguous labels, insufficient colour contrast, and poorly structured navigation. These issues can pose significant challenges for students with visual impairments, cognitive disabilities, and other accessibility needs. The study highlights the need for increased investment in accessibility resources and support services across all European universities, particularly in under-resourced institutions and regions. It underscores the importance of ensuring that all students, regardless of disability, have equal access to education and opportunities.