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In the aircraft industry, there is a shift towards more and all-electric power systems resulting in great research efforts on single components like batteries. At the same time there is an increasing need to investigate and evaluate the long-term behavior of the whole electric power system to ensure safe and sustainable aircraft operation. Focusing on this challenge, the objective of this article is to propose a framework for electric power system assessment in the early design stages. In particular, the focus is on identifying and handling uncertainties regarding failure behavior and degradation, both on the component and system level. The evaluation of different power system topologies is based on the integration of Model-Based Systems Engineering and robust design methods. In this context, another central aspect is the definition of system and component requirements derived from the flight mission profile. SysML diagrams are used to define use cases and possible system topologies. Sensitivity of degradation effects are evaluated using robust design methods. The application of the framework and these methods is illustrated using a short-range aircraft with an all-electric power system. The results highlight the applicability of the framework to cope with the uncertainties that occur in the early design stages and point out fields of further research. [ABSTRACT FROM AUTHOR]

The relevance of trust on the road to successful human-robot interaction is widely acknowledged. Thereby, trust is commonly understood as a monolithic concept characterising dyadic relations between a human and a robot. However, this conceptualisation seems oversimplified and neglects the specific interaction context. In a multidisciplinary approach, this conceptual analysis synthesizes sociological notions of trust and distrust, psychological trust models, and ideas of philosophers of technology in order to pave the way for a multidimensional, relational and context-sensitive conceptualisation of human-robot trust and distrust. In this vein, trust is characterised functionally as a mechanism to cope with environmental complexity when dealing with ambiguously perceived hybrid robots such as collaborative robots, which enable human-robot interactions without physical separation in the workplace context. Common definitions of trust in the HRI context emphasise that trust is based on concrete expectations regarding individual goals. Therefore, I propose a three-dimensional notion of trust that binds trust to a reference object and accounts for various coexisting goals at the workplace. Furthermore, the assumption that robots represent trustees in a narrower sense is challenged by unfolding influential relational networks of trust within the organisational context. In terms of practical implications, trust is distinguished from acceptance and actual technology usage, which may be promoted by trust, but are strongly influenced by contextual moderating factors. In addition, theoretical arguments for considering distrust not only as the opposite of trust, but as an alternative and coexisting complexity reduction mechanism are outlined. Finally, the article presents key conclusions and future research avenues. [ABSTRACT FROM AUTHOR]

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Automated-guided vehicles (AGVs) are considered as an advanced technology for improving intralogistics in manufacturing companies. However, diverging perspectives between management and operational staff on the implementation of AGVs in existing production environments can lead to a lack of employee acceptance and highlight the need for appropriate organizational change management initiatives. At present, there is a lack of knowledge about the success factors for deploying AGVs in manufacturing companies, including human factors such as worker acceptance. We therefore conducted a quantitative survey among production and logistics workers, project leaders, and managers (n = 89) in ten German companies that have already introduced AGVs in their production in order to investigate and compare their perspectives and to derive implications for successful AGV implementation projects. Our findings reveal that workers consider some of the most important acceptance factors as insignificantly addressed by the project management. In addition, we found significant differences in the perspectives of logistics and production workers on the implementation of AGVs, with logistics workers being less satisfied and significantly more concerned about job security. Furthermore, project leaders' ability to accurately anticipate their employees' perspective (perspective taking accuracy) positively influences employees' satisfaction with the implementation of the AGV system. These findings have theoretical implications for research on organizational change and practical implications for AGV implementation projects. [ABSTRACT FROM AUTHOR]

Human-robot interaction (HRI) promises to be a means whereby manufacturing companies will be able to address current challenges like a higher demand for customization. However, despite comparably low costs, there are only few applications in practice. To date, it remains unclear which factors facilitate or hinder the successful introduction of industrial collaborative robots (cobots). In a three-step approach, we first developed a comprehensive two-dimensional framework covering three separate phases and four essential components for human-robot working systems. Secondly, we reviewed related literature to identify relevant success factors. Thirdly, in an online survey we asked leading representatives of German manufacturing companies (n = 81) to assess the importance of these factors from a practical point of view. The results reveal that besides technology-related factors like occupational safety and appropriate cobot configuration, employee-centered factors like the fear of job loss and ensuring an appropriate level of trust in the robot are considered important. However, company representatives seem to underestimate the impact of subtle measures to increase employee acceptance which could be incorporated into internal communication strategies prior to and during the introduction of cobots. Comparative analysis based on three distinct application scenarios suggests that most success factors' practical importance is independent of the motivation for implementing HRI. Furthermore, answers from practitioners in free-text fields reveal that success factors which intuitively come to their mind such as financial factors are not necessarily perceived most important. Finally, we argue for more application-oriented research that focuses on practically relevant factors to guide HRI research, inform cobot development, and support companies in overcoming apparent barriers. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this article is to explore the importance of workplace learning in the context of performance measurement on an organisational level. It shows how workplace learning analytics can be grounded on professional identity transformation theory and integrated into performance measurement approaches to understand its organisation-wide impact. Design/methodology/approach: In a conceptual approach, a framework to measure the organisation-wide impact of workplace learning interventions has been developed. As a basis for the description of the framework, related research on relevant concepts in the field of performance measurement approaches, workplace learning, professional identity transformation, workplace and social learning analytics are discussed. A case study in a European Public Employment Service is presented. The framework is validated by qualitative evaluation data from three case studies. Finally, theoretical as well as practical implications are discussed. Findings: Professional identity transformation theory provides a suitable theoretical framework to gain new insights into various dimensions of workplace learning. Workplace learning analytics can reasonably be combined with classical performance management approaches to demonstrate its organisation-wide impact. A holistic and streamlined framework is perceived as beneficial by practitioners from several European Public Employment Services. Research limitations/implications: Empirical data originates from three case studies in the non-profit sector only. The presented framework needs to be further evaluated in different organisations and settings. Practical implications: The presented framework enables non-profit organisations to integrate workplace learning analytics in their organisation-wide performance measurement, which raises awareness for the importance of social learning at the workplace. Originality/value: The paper enriches the scarce research base about workplace learning analytics and its potential links to organisation-wide performance measurement approaches. In contrast to most previous literature, a thorough conceptualisation of workplace learning as a process of professional identity transformation is used. [ABSTRACT FROM AUTHOR]

Research stresses the importance of social components in learning. The social contact with peers and tutors stimulates reflection and supports higher processes of learning necessary for the internalisation and application of new knowledge. However, merely proposing opportunities for interaction does not necessarily lead to fruitful discussion and collaboration. Social presence and facilitation are key concepts for successful mutual learning. Both are represented in Murphy's collaboration model; social presence forms the basis of collaboration on which discussions and co‐construction of knowledge evolve. Facilitation supports the entire collaboration process. In this paper, an adjusted version of Murphy's model was applied to analyse 1085 comments shared in an online course between career practitioners of a public employment service. The results show that without a dedicated tutor, learners can still be involved in collaborative learning and co‐construction of new knowledge provided that the topic under discussion is highly relevant and controversial. Learners themselves take over social presence and facilitation activities, but less frequently than when a professional tutor facilitates discussions. Ex post summative evaluation revealed that only a few learners applied the gained knowledge in the long‐term. As comparisons with related research suggest, higher facilitation support leading to a higher cognitive interaction with the learning could have better supported the transfer to practice. [ABSTRACT FROM AUTHOR]

Research has shown that providing participants with high‐quality learning material is not sufficient to help them profit most from online education. The level of interaction among participants is another key determinant for learning outcomes. However, merely proposing interaction does not automatically lead to fruitful discussion and collaboration. Specifically, social presence and facilitation activities add value to online discussions. In Murphy's collaboration framework, social presence represents the basis of successful online collaboration from which more reflective discussions and co‐construction can evolve. In this paper, an adjusted version of this framework was applied in a workplace learning context. The content analysis of 1170 comments in an online course for careers practitioners of a public employment service showed that the extended framework generated deeper insights into the dynamics of online discussions. The results show that involvement in collaborative learning at the workplace was supported by a high social presence and influenced by course topic and tasks. Facilitation played an important role in creating a sympathetic sense of community and stimulating co‐creation processes. [ABSTRACT FROM AUTHOR]

This paper introduces a novel approach for estimation of the maximum pressure caused by surge currents in narrow gaps. The new approach was developed based on different experimental tests in the laboratory for surge currents formed as an 8/20- $\mu \text{s}$ impulse. In addition, a clear identification of the dependences of the plasma pressure on different parameters such as the input power and the geometry of the narrow gap was investigated. The validity of the proposed approach was tested using measured and calculated maximum pressure of a different spark gap. The results show that the new technique is simple and efficient for estimating the maximum plasma pressure for similar spark gaps. The estimated pressure can be used in two different ways. It can be used in further investigations to design the sensor system, and on the other hand, it is useful in the development of new surge protective devices to design the geometry of the spark gap and housing. These devices protect electrical devices in the system from an outage caused by overvoltage. [ABSTRACT FROM AUTHOR]

The behavior of switching arcs is well known for time periods of several milliseconds. In other devices such as surge protective devices, where the operation is based on spark gap technology, the time periods are within microseconds. These devices are tested with 8-/20- $\mu \text{s}$ surge currents. The behavior of the arc during this time period is rather unknown. In the event of overvoltages, the basic requirement is to establish an arc with a high conductivity between the main electrodes to conduct the surge current to the equipotential bonding. Due to the high conductivity, an additional current from the distribution grid ensues. This follow current needs to be switched OFF using the current-limiting breaking principle. In order to analyze the arc behavior, when changing from a surge current conduction to a follow current, a basic experimental setup is established. Due to the grid’s alternating voltage, the influence of the synchronization angle is regarded for the two worst-case angles of 90° and 270°. The setup consists of a surge current generator for 8-/20- $\mu \text{s}$ currents up to 25 kA, a distribution transformer with 130 kVA, and a modular spark gap that contains two parallel electrodes in a narrow gap. In this setup, the surge current, follow current, arc voltage, and transformer voltage are measured and discussed. In addition, a high-speed camera is used to visualize the plasma between the electrodes. The data are discussed in order to propose a simplification for the occurring arc. [ABSTRACT FROM AUTHOR]

Collaborative robots are a new type of lightweight robots that are especially suitable for small and medium-sized enterprises. They offer new interaction opportunities and thereby pose new challenges with regard to technology acceptance. Despite acknowledging the importance of acceptance issues, small and medium-sized enterprises often lack coherent strategies to identify barriers and foster acceptance. Therefore, in this article, we present a collection of crucial acceptance factors with regard to collaborative robot use at the industrial workplace. Based on these factors, we present a web-based tool to estimate employee acceptance, to provide company representatives with practical recommendations and to stimulate reflection on acceptance issues. An evaluation with three German small and medium-sized enterprises reveals that the tool's concept meets the demands of small and medium-sized enterprises and is perceived as beneficial as it raises awareness and deepens knowledge on this topic. In order to realise economic potentials, further low-threshold usable tools are needed to transfer research findings into the daily practice of small and medium-sized enterprises. [ABSTRACT FROM AUTHOR]