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The purpose of this paper is to present the application of the boundary element method (BEM) in linear elastic fracture mechanics for analysis of fatigue crack propagation problems in mixed-mode (I+II) using a robust academic software named BemCracker2D and its graphical interface BemLab2D.

The methodology consists in calculating elastic stress by conventional BEM and to carry out an incremental analysis of the crack extension employing the dual BEM (DBEM). For each increment of the analysis, the stress intensity factors (SIFs) are computed by the J-Integral technique, the crack growth direction is evaluated by the maximum circumferential stress criterion and the crack growth rate is computed by a modified Paris equation, which takes into account an equivalent SIF to obtain the fracture Modes I and II. The numerical results are compared with the experimental and/or BEM values extracted from the open literature, aiming to demonstrate the accuracy and efficiency of the adopted methodology, as well as to validate the robustness of the programs.

The paper addresses the numerical simulation of fatigue crack growth. The main contribution of the paper is the introduction of a software for simulating two-dimensional fatigue crack growth problems in mixed-mode (I+II) via the DBEM. The software BemCracker2D coupled to the BemLab2D graphical user interface (GUI), for pre/post-processing, are very complete, efficient and versatile and its does make relevant contributions in the field of fracture mechanics.

The main contribution of the manuscript is the development of a GUI for pre/post-processing of 2D fracture mechanics problems, as well as the object oriented programming implementation. Finally, the main merit is of educational nature.

In recent years, increased awareness on global warming effects led to a renewed interest in all kinds of green technologies. Among them, some attention has been devoted to hybrid-electric aircraft – aircraft where the propulsion system contains power systems driven by electricity and power systems driven by hydrocarbon-based fuel. Examples of these systems include electric motors and gas turbines, respectively. Despite the fact that several research groups have tried to design such aircraft, in a way, it can actually save fuel with respect to conventional designs, the results hardly approach the required fuel savings to justify a new design. One possible path to improve these designs is to optimize the onboard energy management, in other words, when to use fuel and when to use stored electricity during a mission. The purpose of this paper is to address the topic of energy management applied to hybrid-electric aircraft, including its relevance for the conceptual design of aircraft and present a practical example of optimal energy management.

To address this problem the dynamic programming (DP) method for optimal control problems was used and, together with an aircraft performance model, an optimal energy management was obtained for a given aircraft flying a given trajectory.

The results show how the energy onboard a hybrid fuel-battery aircraft can be optimally managed during the mission. The optimal results were compared with non-optimal result, and small differences were found. A large sensitivity of the results to the battery charging efficiency was also found.

The novelty of this work comes from the application of DP for energy management to a variable weight system which includes energy recovery via a propeller.

The purpose of this study is to identify the relationship between collaborative innovation and the financial performance of information technology (IT) firms through the mediating role of strategic agility and absorptive capacity. Customer knowledge management capability (CKMC) is also explored as a potential moderator.

Data were collected from 300 respondents working in different small to medium IT enterprises operating in different cities around Portugal. The simple random sampling method was used for data collection, and Smart partial least squares-structural equation modeling (Smart PLS-SEM version 3.2.8) was used to test the hypotheses.

The findings demonstrate that collaborative innovation contributes significantly to the financial performance of IT firms in Portugal. The results also indicate that absorptive capacity and strategic agility both positively and significantly affect the relationship between collaborative innovation and firms’ financial performance. However, while the moderating role of CKMC has a positive and significant effect on the relation between collaborative innovation and strategic agility, CKMC insignificantly moderates the relation between collaborative innovation and absorptive capacity.

Few studies have explicitly connected collaborative innovation with firms’ financial performance; this study attempts to fill that gap. Moreover, this research investigates the mediating role of strategic agility and absorptive capacity in the relationship between collaborative innovation and financial performance. Finally, by discussing the moderating effect of CKMC, which leads to enhanced financial performance, this study proposes that when complex and unpredictable situations occur, managers should focus on customer-oriented strategies and innovation at the same time to outpace their competitors.

Introduction: Numerous decision-making situations are faced in education where Artificial Intelligence may be prevalent as a decision-making support tool to capture streams of learners’ behaviours.

Purpose: The purpose of the present study is to understand the role of AI in student performance assessment and explore the future role of AI in educational performance assessment.

Scope: The study tries to understand the adaptability of AI in the education sector for supporting the educator in automating assessment. It supports the educator to concentrate on core teaching-learning activities.

Objectives: To understand the AI adaption for educational assessment, the positives and negatives of confidential data collections, and challenges for implementation from the view of various stakeholders.

Methodology: The study is conceptual, and information has been collected from sources comprised of expert interactions, research publications, survey and Industry reports.

Findings: The use of AI in student performance assessment has helped in early predictions for the activities to be adopted by educators. Results of AI evaluations give the data that may be combined and understood to create visuals.

Research Implications: AI-based analytics helps in fast decision-making and adapting the teaching curriculum’s fast-changing industry needs. Students’ abilities, such as participation and resilience, and qualities, such as confidence and drive, may be appraised using AI assessment systems.

Theoretical Implication: Artificial intelligence-based evaluation gives instructors, students, and parents a continuous opinion on how students learn, the help they require, and their progress towards their learning objectives.

This paper compares traditional and digital banks in nine categories of complaints and provides insights to improve complaint management performance.

A sample of the major Brazilian banks was defined, with four traditional and four digital banks. The grey relational analysis (GRA) method was applied as an analytical tool to compare the most frequent complaints of traditional and digital banks. The most critical complaints identified were considered to discuss potential improvements in complaint management using quality and service management system concepts.

The GRA method enabled the development of a ranking of nine complaint categories, considering the uncertainty involved in the data and differentiating between traditional and digital banks. The most critical complaint categories, regardless of business model, were “unauthorized charges” and “poor service,” which were ranked first and second in the frequency rankings. Traditional and digital banks differed the most in the complaint category “unfair charge,” ranking third and eighth in the rankings, respectively.

Managers from traditional and digital banks can improve complaint management performance by applying ISO 9001 and ISO 20000 concepts such as incident, problem, change, service level, availability, capacity, information technology service continuity and financial management.

The study's findings can help bank managers improve service levels in the face of technological competition. Improving these organizations is an important factor for developing countries such as Brazil.

This paper reveals the differences between two business models regarding complaint management. It also considers a methodological approach to include the uncertainty related to customers' perception and subjectivity inherent to complaints.

We present a critical literature review debating Brazilian research on social and environmental accounting (SEA). The aim of this study is to understand the role of politics in the construction of hegemonies in SEA research in Brazil. In particular, we examine the role of hegemony in relation to the co-option of SEA literature and sustainability in the Brazilian context by the logic of development for economic growth in emerging economies. The methodological approach adopts a post-structural perspective that reflects Laclau and Mouffe’s discourse theory. The study employs a hermeneutical, rhetorical approach to understand and classify 352 Brazilian research articles on SEA. We employ Brown and Fraser’s (2006) categorizations of SEA literature to help in our analysis: the business case, the stakeholder–accountability approach, and the critical case. We argue that the business case is prominent in Brazilian studies. Second-stage analysis suggests that the major themes under discussion include measurement, consulting, and descriptive approach. We argue that these themes illustrate the degree of influence of the hegemonic politics relevant to emerging economics, as these themes predominantly concern economic growth and a capitalist context. This paper discusses trends and practices in the Brazilian literature on SEA and argues that the focus means that SEA avoids critical debates of the role of capitalist logics in an emerging economy concerning sustainability. We urge the Brazilian academy to understand the implications of its reifying agenda and engage, counter-hegemonically, in a social and political agenda beyond the hegemonic support of a particular set of capitalist interests.

Building on a business network perspective, the paper addresses the following question: Why do firms move between cooperation and competition in the context of high-tech industry? Hence, the purpose of this study is to contribute to the understanding of the complex cooperation–competition interplay between actors in a business network.

A single case study within the information and communication technology industry is undertaken and illustrates the cooperation–competition interplay in projects of technology.

The authors discuss the implications of interdependence on relationship dynamics. The main argument is that business relationships survive despite periods of competition if interdependence is high. Thus, firms move between a state of cooperation and a state of competition within business relationships, rather than ending the relationships when starting to compete.

This study suggests that managers need to pay attention to how different degrees of interdependence lead firms to be embedded in cooperative or competitive forms of relationships.

The paper contributes to the ongoing debate about cooperation, competition and coopetition within international business and industrial marketing literature. An interesting aspect in the paper is the cooperation–competition interplay, which is associated with positioning. A centrally positioned actor will choose who to bring into the partnership, with positioning concomitantly changing from project to project. The willingness of being a central actor, i.e. a project leader, places traditional buyer–supplier partners in competition. Thus, cooperation and/or competition becomes contextual.

The purpose of this paper is to evaluate the fatigue process through the dynamic analysis of the global structural model and local static sub-modelling in a critical detail using the hot-spot stress approach. The detail was studied in three different positions at the “Alcácer do Sal” access viaduct, and the methodologies from the IIW and Eurocode EN 1993-1-9 were compared.

In this study, the fatigue life process based on the hot-spot stress approach was evaluated using a global dynamic analysis and a local sub-modelling based on a static analysis of welded connections in the “Alcácer do Sal” railway structure, Portugal, taking into consideration the recommendations from IIW and Eurocode EN 1993-1-9. The hot-spot stresses were calculated through the static analysis of the sub-model of the welded connection for each vibration mode with the aim to obtain the temporal stresses using the modal coordinates and modal stresses of the extrapolation points. The Ansys® and Matlab® softwares were used for the numerical analysis and the hot-spot stress calculations, respectively.

The proposed methodology/approach to obtain fatigue assessment is based on the modal analysis of the global structural model and local static sub-modelling. The modal analysis was used to extract the boundary conditions to be used in the local model to determine the temporal stresses of the extrapolation points. Based on the modal superposition method, the stresses as function of time were obtained for fatigue life evaluation of a critical detail by the hot-spot stress approach. The detail was studied in three different positions.

In the present study, a global-local fatigue methodology based on dynamic analysis of the global structural model and local static sub-modelling of the critical detail using the hot-spot stress approach is proposed. Herein, the modal analysis of the global structural model supported by the modal superposition method was used to obtain the matrix of modal coordinates. The static analysis of the local sub-model for each mode from the modal analysis of global structural model was done to estimate the hot-spot stresses. The fatigue damage calculation was based on S-N curve of the critical detail and rainflow method. The IIW recommendation proved to be more conservative compared to the proposed rules in the Eurocode EN 1993-1-9. The global-local modelling based on dynamic analysis is an important and effective tool for fatigue evaluation in welded joints.

There have been various concerns about the petroleum industry regulation in Nigeria, including issues regarding the protection of host communities. The host communities have hardly derived sustainable developmental value from petroleum resource exploration from their community. Instead, the exploration of petroleum and other mineral resources has caused some environmental, social and economic setback for these host communities. On 17 August 2021, the Petroleum Industry Act (PIA) 2021 was signed into law after over two decades of legislative stalemate. The PIA proposes a series of reforms purported to revolutionalise the petroleum industry. According to President Buhari, the Act will create a regulatory sphere that will ensure transparency and accountability across the oil and gas value chain (Ailemen, 2021). Chapter 3 of the Act deals with host communities' concerns. Its overall aim is to ensure host communities have access to sustainable prosperity. The notion of sustainable prosperity implies that the Act seeks to elevate host communities from the poverty baseline to a level of prosperity that satisfies the social, economic, environmental and intergenerational features. Therefore, this chapter examines the provisions of the Act, particularly Chapter 3, to determine its potential to achieve sustainable prosperity for host communities. The chapter shall also identify the weaknesses in the Act, which would otherwise limit its sustainable prosperity goal and how these challenges can be addressed.