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Abstract
This article proposes the use of social representation theory to validate the structural model of structural equation modeling, thereby enhancing the understanding of the research object. To achieve this, it was employed action research to construct, implement, and confirm the practical feasibility of the metho-dological procedures described herein. This was accomplished through their practical application in a case analysis. It was possible to validate the structural model used in structural equation modeling by applying the proposed methodological procedures to a case involving the governance system construct. This validation opens the possibility for future research to use these procedures in conjunction to validate theoretical models and the causal relationships between their constructs. Therefore, the primary theoretical contribution of this paper is the proposition of a research methodology that combines social representation theory with structural equation modeling to validate the structural model. This approach reduces the risk of using the statistical method to confirm or refute a theoretical model whose causal relationships may not represent a reality supported by practice.

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This article comparedidentified models in the literature that incorporates sustainability in project management, with an integrated model used as reference, mapping their points of similarity. For this purpose, bibliographic research of 90 articles from the Web of Science and Scopus databases was carried out, which address the themes of sustainability and project management. The reference model was compared with 16 models identified during the literature search, through comparative analysis and grounded theory. As a result, the study presents the identified similarity between model & PRIME;s constructs. It is concluded that there is no pattern or convergence between the different models identified, that thereference model plays a role in stimulating the integration of sustainability with project management in a more comprehensive way.

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Purpose The purpose of this paper is to assess the impact of a maintenance philosophy, Total Productive Maintenance (TPM), on the operational performance of the Portuguese industry, identifying how it enables the systematic reduction of waste in maintenance. Design/methodology/approach A structured questionnaire was constructed and sent to 472 Portuguese enterprises, having obtained a sample constituted of 84 valid answers. With a five-point Likert scale, it was possible to assess the impact of the TPM on five operational performance dimensions, being them: quality, flexibility, productivity, safety and costs. Findings It was found that the planned maintenance, together with education and training are the practices with the highest degree of implementation in the Portuguese industry, exceeding 70% for both. The productivity is the dimension with a higher degree of impact from the implementation of TPM and costs the dimension that suffered a lesser impact. Practical implications This paper shows and analyses the current state of TPM implementation in the Portuguese industry and it will be useful for maintenance professionals, researchers and others concerned with maintenance, in order to understand the effects of TPM implementation on the operational performance of the Portuguese industries. Originality/value The findings from this paper will be valuable for professionals who desire and are looking forward to implement an effective maintenance approach in the maintenance management system, in order to achieve the excellence in maintenance.

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To ensure the safety of passengers concerning virus propagation, such as COVID-19, and keep the turnaround time at low levels, airlines should seek efficient aircraft boarding strategies in terms of both physical distancing and boarding times. This study seeks to analyze the impact of different boarding strategies in the context of the International Air Transport Association's recommendations during the pandemic to reduce interference and physical contact between passengers in airplanes. Boarding strategies such as back-to-front, outside-in, reverse pyramid, blocks, Steffen, and modified optimal have been tested in this context. This study extends the previous literature using discrete event simulation to evaluate the impact of the occupation of the middle seat by family members only. This study also analyses the impact of having passengers carrying hand luggage and priority passengers on the performance of these strategies concerning boarding times. In general, the simulation results revealed a 15% improvement in boarding times when the reverse pyramid strategy is used compared to a random strategy, which essentially results from a reduction in the boarding interferences between passengers. The results also show that Steffen's strategy is the best performing, while the blocks strategy results in the worst performance. This study has practical implications for airline companies concerning both operation efficiency and passenger safety.

Abstract
(1) Background: In this study on Robotic Process Automation (RPA), the feasibility of sustainable RPA implementation was investigated, considering user requirements in the context of this technology's stakeholders, with a strong emphasis on sustainability. (2) Methods: A multi-objective mathematical model was developed and the Weighted Sum and Tchebycheff methods were used to evaluate the efficiency of the implementation. An enterprise case study was utilized for data collection, employing investigation hypotheses, questionnaires, and brainstorming sessions with company stakeholders. (3) Results: The results underscore the significance of user requirements within the RPA landscape and demonstrate that integrating these requirements into the multi-objective model enhances the implementation assessment. Practical guidelines for RPA planning and management with a sustainability focus are provided. The analysis reveals a solution that reduces initial costs by 21.10% and allows for an efficient and equitable allocation of available resources. (4) Conclusion: This study advances our understanding of the interplay between user requirements and RPA feasibility, offering viable guidelines for the sustainable implementation of this technology.