Abstract
L-systems have been used in Computer Graphics, namely for modelling plants, as well as in a few experiments to model urban environments. However, the lack of geospatial awareness is a limitation and in spite of some developments like open L-systems, that introduced the ability to communicate with the environment, there was a need for more flexibility. This paper presents Geospatial L-systems, a new extension of L-systems that incorporates geospatial awareness, and shows an application in the area of expeditious modelling of urban environments. A modelling system, named XL3D, generates virtual urban environments automatically from a XML based document that contains a modelling specification and accesses data sources in an interoperable way. The integration of geospatial L-systems in this modelling system has increased the potential for automation and the potential to generate virtual urban environments with a higher level of detail and visual fidelity, with a lower level of complexity of the modelling processes. These facts are shown in a case study where a virtual urban environment, taken from an area in the Porto downtown, is generated by this solution.

Abstract
During the health crisis caused by COVID-19, virtual reality (VR) proved to be useful for the tourism industry, allowing this industry to continue working despite the restrictions imposed. However, it remains to be seen if the impact of this sanitary crisis in the tourism industry influenced managers' intention to adopt this technology in the post-pandemic period. To fill this gap, a qualitative methodological approach was adopted, using the MAXQDA20 software and interviews with managers of tourism enterprises. The results show that the willingness to invest in technology, the perception of VR as a business strategy, and the perception of the impact of the pandemic are factors that regulate the intention of companies to adopt VR. In addition, prior experience with VR and the perception of technical support are also important for its adoption. Thus, it was concluded that VR can be a valuable sustainable strategy for tourism companies to address the challenges imposed by the pandemic. However, adopting the technology depends on factors such as financial availability, business strategy, and previous experience with VR. Furthermore, tourism companies must also receive adequate technical support to ensure its correct implementation.

Abstract
The use of Virtual Reality (VR) technology to train professionals has increased over the years due to its advantages over traditional training. This paper presents a study comparing the effectiveness of a Virtual Environment (VE) and a Real Environment (RE) designed to train firefighters. To measure the effectiveness of the environments, a new method based on participants' Heart Rate Variability (HRV) was used. This method was complemented with self-reports, in the form of questionnaires, of fatigue, stress, sense of presence, and cybersickness. An additional questionnaire was used to measure and compare knowledge transfer enabled by the environments. The results from HRV analysis indicated that participants were under physiological stress in both environments, albeit with less intensity on the VE. Regarding reported fatigue and stress, the results showed that none of the environments increased such variables. The results of knowledge transfer showed that the VE obtained a significant increase while the RE obtained a positive but non-significant increase (median values, VE: before - 4 after - 7, p = .003; RE: before - 4 after - 5, p = .375). Lastly, the results of presence and cybersickness suggested that participants experienced high overall presence and no cybersickness. Considering all results, the authors conclude that the VE provided effective training but that its effectiveness was lower than that of the RE.

Abstract
The sense of presence is an important aspect of virtual reality experiences, being increasingly researched in educational contexts for its potential association with learning outcomes. A panorama of how these investigations have been conducted could help researchers and practitioners to harness this potential and find new directions. A systematic literature review was conducted to contribute to this perspective, with a comprehensive analysis of 140 primary studies recovered from five worldwide databases. The results show an overview of 24 years of research, with a summarization of areas, factors, and methodological approaches that have been the focus of investigation when these three variables of interest (VR, sense of presence, and learning) are together. We conclude with a list of research gaps that need to be addressed and a research agenda, identifying current and emerging challenges.

Abstract
The expansion of augmented reality across society, its availability in mobile platforms and the novelty character it embodies by appearing in a growing number of areas, have raised new questions related to people's predisposition to use this technology in their daily life. Acceptance models, which have been updated following technological breakthroughs and society changes, are known to be great tools for predicting the intention to use a new technological system. This paper proposes a new acceptance model aiming to ascertain the intention to use augmented reality technology in heritage sites-the Augmented Reality Acceptance Model (ARAM). ARAM relies on the use of the Unified Theory of Acceptance and Use of Technology model (UTAUT) model's constructs, namely performance expectancy, effort expectancy, social influence, and facilitating conditions, to which the new and adapted constructs of trust expectancy, technological innovation, computer anxiety and hedonic motivation are added. This model was validated with data gathered from 528 participants. Results confirm ARAM as a reliable tool to determine the acceptance of augmented reality technology for usage in cultural heritage sites. The direct impact of performance expectancy, facilitating conditions and hedonic motivation is validated as having a positive influence on behavioural intention. Trust expectancy and technological innovation are demonstrated to have a positive influence on performance expectancy whereas hedonic motivation is negatively influenced by effort expectancy and by computer anxiety. The research, thus, supports ARAM as a suitable model to ascertain the behavioural intention to use augmented reality in new areas of activity.

Abstract
Presence is often used to evaluate Virtual Reality (VR) applications. However, the raw scores are hard to interpret and need to be compared to other data to be meaningful. This paper leverages a database of 1909 responses to the Igroup Presence Questionnaire (IPQ) in different contexts to put forward a scale that qualitatively interprets raw Presence scores for VR experiences. The qualitative grading encompasses the acceptability dimension and analogous academic grading scales ranging from A to F and the adjective of such scores in a scale from Excellent to Unacceptable. Furthermore, the qualitative grading system encompasses Presence and its subscales Spatial Presence, Involvement, and Experienced Realism as defined by the IPQ. Adopting this grading system, supported by a robust dataset of Presence scores, enables practitioners to evaluate and interpret individual IPQ scores, allowing them to gain insights regarding the evaluated applications' effectiveness.