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The COVID-19 pandemic has had previously unimaginable and far-reaching effects on higher education globally (Baker et al. 2022; Cranfield et al. 2021; Kara 2021; Le Grange 2020). On top of the widespread loss felt by students and teachers across the world, we have had to make rapid changes to previously taken-for-granted ways of doing, being, learning and teaching (Baker et al. 2022; Cranfield et al. 2021). Emergency Remote Teaching and Learning (ERTL) brought constraints and opportunities, challenges and innovations. This article gives form to the statement: “there is an opportunity in the moment for genuine equity-focused innovation in policy-making, provision and pedagogy” (Czerniewicz et al. 2020). We use a theoretical framework of structure, culture and agency through which to view possibilities for transformation of pedagogy, and a form of semi-autoethnography as methodology. Two lecturers, one in the Humanities (Education) and one in the Life Sciences, wrote extended narratives of their experiences of ERTL and the other authors then posed a series of questions to the story authors, which elicited a set of analytic descriptions and explanations. Through iterations of this analysis, we identified two important themes: attending to students’ socio-emotional needs and developing students’ engagement, self-regulation and reflexivity. The analysis identifies key opportunities and challenges that these required and how they were addressed by the lecturers concerned. Based on the analysis and drawing on Case’s (2015b) argument for an expanded sense of agency for students, we argue that the lecture is a key structural and cultural element of the university space that was disrupted during the pandemic and can be transformed going forward. We thus argue for decentering the lecture. Furthermore, we argue that care and concern for students has not been a primary cultural element of teaching and learning in higher education, for structural reasons, and that it should be an integral part of pedagogies going forward.

The continuous professional learning of academics as university teachers is a national imperative in South Africa. At our university, a Postgraduate Diploma in Education (Higher Education) was introduced in 2015 with the aim to professionalise university teaching through a formal qualification. Students (i.e., candidates) must transition in two ways: firstly, from being disciplinary specialists to being students again; and secondly, into the community of scholarly teaching in higher education. This article examines the liminality experienced by candidates as they navigate the programme and learn to belong to a new scholarly teaching community. Drawing on empirical data collected from graduates and programme coordinators, the authors track candidates’ shifting identities and showcase how, though initially turbulent and unsettling, the process of learning to belong to a new teaching identity can be rewarding and enriching. The authors conclude by discussing the conditions required to enable candidates to acquire a strong university-teacher identity. Keywords: belonging, higher education, identity, liminality, professional learning, threshold concepts

Transfer Path Analysis (TPA) designates the family of test-based methodologies to study the transmission of mechanical vibrations. Since the first adaptation of electric network analogies in the field of mechanical engineering a century ago, a multitude of TPA methods have emerged and found their way into industrial development processes. Nowadays the TPA paradigm is largely commercialised into out-of-the-box testing products, making it difficult to articulate the differences and underlying concepts that are paramount to understanding the vibration transmission problem. The aim of this paper is to derive and review a wide repertoire of TPA techniques from their conceptual basics, liberating them from their typical field of application. A selection of historical references is provided to align methodological developments with particular milestones in science. Eleven variants of TPA are derived from a unified framework and classified into three categories, namely classical, component-based and transmissibility-based TPA. Current challenges and practical aspects are discussed and reference is made to related fields of research.

This thesis deals with new methods, which can determine the dynamic response of a complex system identified in operation, based on the knowledge of its subsystem dynamics and excitation. In the first part of this thesis, the identification of component excitation and its transmission into the total system will be addressed. The identification of the internal component excitation is performed on a test bench, on which equivalent forces at the component interface to the test setup are measured. The total system’s response is calculated on the knowledge of its dynamic properties from the component interface onwards. It is shown that physically correct responses for the systems in front of the component’s interface can be calculated. A compensation technique is also outlined to eliminate possible test bench influences. In this thesis, this first approach is called the Gear Noise Propagation (GNP) method, which can be seen as a special class of the well known Transfer Path Analysis (TPA) method. The method could be partially validated on the vibration propagation of a Rear Axle Differential (RAD) in a vehicle, also showing that test bench influences can be minimized in real life applications. In the second part, a new experimental strategy is developed, which enables the identification of systems in operation. In this thesis the method is referred to as the Operational System Identification (OSI) method. It is shown that the signal processing involved yields better FRF estimates than the classical Cross Power Spectrum (CPS) and Auto Power Spectrum (APS) averaging technique. In addition the method has been successfully validated by comparison with the Principle Component Analysis (PCA) method on a test object. Application of the method to an operating vehicle reveals some interesting dependencies of its system dynamics on temperature and applied engine torque. The third part of this thesis deals with methods which improve coupling results in experimental Dynamic Substructuring (DS) applications. First a general framework is presented with which different kinds of substructuring methods developed in the past can be classified. Thereafter methods which improve subsystem connectivity and compensate for shaker’s side force excitation are presented. An error propagation method is also developed with which the uncertainty on the coupled system FRF can be determined, based on the uncertainties of its subsystems. Validation of the new methods on a vehicle’s Rear Axle system shows good improvements could be achieved. In addition it will be shown that random errors on the subsystem FRF only play a significant role for very lightly damped systems. Yet in general, bias errors in the subsystem measurement and in the subsystem coupling definition are found to yield most of the discrepancies in experimental DS. Combinations between the methods developed in the first three parts are made in the fourth part of this thesis. It is shown that experimental DS is an efficient tool to identify influences of component operational parameters on the total systems performance. Furthermore it is shown that DS is helpful in sensitivity analysis and simple component design.