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Part of the runway at Madeira Airport is a platform above the sea at a 60 m height, supported by a series of frames. When aircraft land on this section, a load is exerted on the structure, resulting in bending of the beams which constitute the frames. A vision-based monitoring system was devised and implemented to measure the deflection of the runway's beams when a landing occurs.

An area on the midspan of two beams, located on the area where aircraft are most likely to land, was prepared with a speckle pattern, and a camera was assembled above a column on each of the adjacent frames, enabling the computation of displacements using digital image correlation (DIC). The camera continuously acquires images of the monitored area and compares them to a reference using DIC. If a displacement is detected, a number of frames before and after this event are saved for further DIC processing.

The installed systems successfully detected several events corresponding to landings and, for each of those events, measured the deflection of the beams over time and computed displacement fields for critical images, with strain values obtained up to this point being too small to measure using the current system.

This work provides novel insights into the behaviour of a unique structure and constitutes the first use of a vision system in its structural monitoring operations. It is also a valuable development in the implementation of automated DIC monitoring systems in locations of difficult access.

The authors seek to advance the understanding of small- and medium-sized enterprise (SME) internationalization at the regional level and examine the role of home market institutions in this process.

The authors analyze hypotheses with data from SMEs in five country markets and from the Global Entrepreneurship Monitor. A cluster analysis establishes the regional diversification patterns (based on regional diversification scope, speed and rhythm) and a multinomial regression tests the effect of home market institutions on their adoption.

The results offer a refined picture of SME regional diversification by revealing three patterns: intra-regionally focused firms, late inter-region diversifiers and early inter-region diversifiers. They also suggest that the adoption of these patterns is determined by SMEs' home market institutions.

The authors develop a nuanced understanding of SME internationalization by building upon and expanding the regionalization rationale in the internationalization patterns literature. Additionally, the authors address the acknowledged, yet rarely investigated, country-level determinants of internationalization patterns.

The purpose of this paper is to discuss the literature on concept theory in library and information science (LIS) from an epistemological perspective, ascribing each paper to an epistemological family and discussing their relevance in the context of the knowledge organization (KO) domain.

This paper adopts a hermeneutic approach for the analysis of the texts that compose the corpus of study following contingency and categorical analyses. More specifically, the paper works with Bardin’s contingency analysis and follows Hjørland’s families of epistemologies for the categorization.

The analysis corroborates the observations made for the last ten years about the scarcity of studies on concept theory in LIS and KO. However, the study also reveals an epistemological turn on concept theory since 2009 that could be considered a departure from the rationalist views that dominated the field and a continuation of a broader paradigm shift in LIS and KO. All analyzed papers except two follow pragmatist or historicist approaches.

This paper follows-up and systematizes the contributions to the LIS and KO fields on concept theory mainly during the last decade. The epistemological analysis reveals the dominant views in this paradigm shift and the main authors and trends that are present in the LIS literature on concept theory.

This paper aims to propose an evaluation method to compare two different Human–Robot Interaction (HRI) solutions that can be used for on-line programming in an industrial context: a force guidance system and the traditional teach pendant operation.

The method defines three evaluation criteria (agility, accuracy and learning) and describes an experimental approach based on the analysis of variance to verify the performance of guidance systems according to these criteria. This method is used in this paper to compare the traditional teach pendant interface with an implementation of a force guidance system based on the use of an external force/torque sensor.

The application of the proposed method to an off-the-shelf industrial robot shows that the force guidance system has a better performance according to the agility criterion. Both solutions have a similar performance for the accuracy criterion, with a limit of about 2 mm in the achieved position accuracy. Regarding the learning criterion, the authors cannot affirm that any of the methods has an improved agility when the operator repeats the tasks.

This work supports the selection of guidance systems to be used in on-line programming of industrial applications. It shows that the force guidance system is an option potentially faster than the teach pendant when the required positioning accuracy is greater than 2 mm.

The new method proposed in this paper can be applied to a large range of robots, not being limited to commercial available collaborative robots. Furthermore, the method is appropriate to accomplish further investigations in HRI not only to compare programming methods but also to evaluate guidance systems approaches or robot control systems.

We investigate the role of market uncertainties as determinants of the adoption of control and prediction in the internationalization of small- and medium-sized enterprises (SMEs). Building on the possibility that uncertain markets may lead to trade-offs between these strategies, as suggested by the convergence between effectuation and internationalization research, we differentiate between uncertainties originated in SMEs’ home and host countries. We test our hypotheses with a cross-country data set encompassing 597 SMEs surveyed in Brazil, China, Poland, and Italy. Our results indicate that home-country uncertainty is related to the adoption of control strategies, while host-country cultural uncertainty is related to prediction efforts. Moreover, internationalization knowledge emerged not as a moderator of these relationships but as a relevant antecedent of both control and prediction. Our findings have implications for the use of effectuation in the study of SME internationalization and also for the conceptualization of the effectuation process itself.

Aims to focus on steady state and transient state analysis of basic properties of new solution for a single‐phase serial AC voltage controller. Furthermore, simulation and experimental test results of 3 kVA models are provided to confirm and verify the theoretical approach.

Presents a converter with auxiliary transformer and bipolar PWM AC matrix‐reactance chopper (MRC), based on Ćuk B2 topology. The MRC has the possibility of bipolar AC voltage conversion with magnitude of voltage transformation function greater than 1. The peak voltage detection method in the control circuit is applied to fast control of the load voltage changes. The steady state and transient state theoretical analysis based on averaged models of the presented controller is used. There is a four‐terminal description of the basic properties in the presented approach.

In the proposed solution only half the number of switches compared with the case of full bridge matrix chopper solution is used. The nominal load voltage can be obtained even for 50 per cent step‐down of the supply voltage.

Presents new topology and properties of single‐phase serial AC voltage controller.

In the twenty-first century, the family has been turning towards a greater plurality of training paths, situations, family and parental arrangements. However, despite changes in legislation, values, representations and practices, the word family remains inexorably associated with the heterosexual bi-parental model. This paper aims to contribute to the knowledge of the family dynamics of non-heterosexual people, mainly concerning the process of transition to parenting, in relation to family changes in Portuguese society. To do so this study aims to analyze four in-depth interviews¹ with young adults, women and men who have a homoconjugality relationship and a project of parenting in mind.

Based on a qualitative methodology the study intends to discuss issues related to the challenge of heteronormativity, equality within the couple, projects and gender representations of parenthood and in particular what it means for the men and women interviewed, to be a father and to be a mother in a same sex couple and how they project themselves as fathers and mothers.

The study discusses all these issues always in relation to the biographical trajectories, the history and life as a couple and the structural and individual resources, such as school and professional qualifications. It also analyzes the main difficulties experienced in revealing their sexuality to the significant others and the difficulties / strategies they anticipate in relation to the parenting project.

The authors conclude that female interviewees show greater independence of a male figure in relation to their parental projects and anticipate less difficulty in their parental skills compared with the gay man interviewed.

To analyze the dynamics of parenting in same-sex couples, this study also points out to the need to construct a model of analysis capable of articulating structural factors, such as job insecurity and heteronormativity, biographies and individual resources and profiles of conjugal interactions.