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A conceptual design method for composite material stiffened panels used in aircraft tail structures and unmanned aircraft has been developed to bear compression and shear loads.

The method is based on classical laminated theory to fulfil the requirement of building a fast design tool, necessary for this preliminary stage. The design criterion is local and global buckling happen at the same time. In addition, it is considered that the panel does not fail due to crippling, stiffeners column buckling or other manufacturing restrictions. The final geometry is determined by minimising the area and, consequently, the weight of the panel.

The results obtained are compared with a classical method for sizing stiffened panels in aluminium. The weight prediction is validated by weight reductions in aircraft structures when comparing composite and aluminium alloys.

The work is framed in conceptual design field, so hypotheses like material or stiffeners geometry shall be taken a priori. These hypotheses can be modified if it is necessary, but even so, the methodology continues being applicable.

The procedure presented in this paper allows designers to know composite structure weight of aircraft tails in commercial aviation or any lifting surface in unmanned aircraft field, even for unconventional configurations, in early stages of the design, which is an aid for them.

The contribution of this paper is the development of a new rapid methodology for conceptual design of composite panels and the feasible application to aircraft tails and also to unmanned aircraft.

The research aims to investigate how digital transformation (DT), entrepreneurial orientation (EO) and socioemotional wealth (SEW) impact the financial performance of family firms in uncertain business environments. Drawing from existing literature, we propose that DT and EO drive firm performance. Additionally, we suggest a new role for SEW, which positively moderates this relationship in family firms, especially in terms of risk behavior and innovation for survival.

We used the STEP Consortium’s 2020–2021 database, derived from a global survey that explored how family businesses responded to environmental shocks. Following STEP’s definitions, we proposed three hypotheses and tested two models using structural equation modeling.

The findings show that EO significantly enhances the impact of DT on family firm performance. Family businesses exhibit a notable willingness to take strategic venture risks to protect their SEW. These findings align with conclusions drawn in related literature, supporting all hypothesized relationships proposed.

The study has made an applied contribution by challenging the misconception that family firms are outdated and provides insights into supporting their approach to entrepreneurship, innovation and transgenerational entrepreneurship. Furthermore, it provides business families and consultants with a new view of SEW as a strategic asset.

Our study adds to the literature by showing how entrepreneurial orientation catalyzes the positive impact of digital transformation on firm financial performance. We also highlight the contextual influence on family firm decision-makers' risk propensity, which affects SEW development and firm outcomes. This context dependency of SEW can hinder or enhance performance, offering new research and support avenues for family firms.

The growing displacement of theory and other forms of wide-ranging knowledge of social phenomena by empirical research methods in economics is widely noted by economists and historians of economic knowledge. Less attention has been devoted, however, to understand the materialization of such changes in the scientific practices. This article studies the recent transformations in the epistemological practices at CEDE, a research center in Colombia. I use a machine learning technique called Topic Modeling, interviews to CEDE researchers, and exegesis of papers to characterize a shift in the production of knowledge in microeconometrics at CEDE during the years 2000 and 2018. I explain this shift by characterizing two sets of epistemological practices that implies a recent tendency to disdain research that cannot make a “strong” causal inference.

This chapter investigates the environmental behaviours of three, four- and five-star hotels in Azuay (Ecuador). The methodology involved a quantitative research that measured the relationship between environmental responsibility (Gallardo, Sanchez, & Corchuelo, 2013) and stakeholder engagement (Kostova & Roth, 2002; Llamas-Sanchez, García-Morales, & Martin-Tapia, 2013; Vargas-Sánchez & Riquel-Ligero, 2012). The main findings suggest that the managers of the hotels implement environmental practices as they reduce waste, gas emissions and recycle materials. These practices are aligned with Ecuador’s extant legislation and regulations. In conclusion, this contribution implies that the hotels’ managers ought to communicate about their environmental responsibility with their stakeholders, including the employees, suppliers and customers.

The purpose of this paper is to introduce the Focus Section “Creativity and innovation in the firm: managerial antecedents and effects on employees”, which forms the first of two separate parts of the journal special issue.

The guest editors summarize the three papers which comprise this Focus Section.

The selected papers are found to relate to the Focus Section theme of impact of managers’ characteristics on creativity and innovation, and innovation effects on employees.

The paper shows that the Focus Section offers new insights for students of innovation and creativity by providing fresh ideas about whether and how top manager characteristics influence organizational creativity through their effect on employees’ creativity, by means of idealization, inspirational motivation and intellectual stimulation.

The purpose of this study of which this work is only the first part, is the development of conceptual design tools to perform an optimized design of the rear fuselage and tail surfaces. The development of a new and extensive database of transport aircraft and an analysis of certain general, rear fuselage and horizontal stabilizer parameters of the aircraft are presented in this paper.

In addition to the development of a comprehensive high accurate database, linear and non-linear correlations between different parameters of the aircraft have been established. Data were analyzed using comparison criteria between aircraft database based on the mission, the number of engines installed or arrangement of the tail surfaces.

It has been possible to obtain very relevant, linear and non-linear correlations for critical design parameters to optimize the design of the rear fuselage and horizontal tail.

In the case of the tail cone, the data have not yielded significant correlations. On the other hand, there are some regressions that do not work well in some cases and for which it would be good to further expand the database.

Results obtained greatly improve the existing methods for conceptual design, which usually pay no attention to the rear part of the aircraft. Besides, these new procedures are adapted to different categories of aircraft, allowing greater optimization of the designs.

The novel contribution of this work is focused on the development of a new high-fidelity database and includes many more aircraft than any other work previously released. Also, new correlations, linear and non-linear, additional parameters not considered in previous studies, and differentiated by category of aircraft studies are provided.

Barabási‐Albert and small‐world networks. In this model, the order‐disorder phase transition of the order parameter is well defined on small‐world networks. We calculate the value of the critical temperature Tc for several values of rewiring probability p of the directed small‐world network. For directed small‐world networks we obtained a second‐order phase transition for p = 0.2 and first‐order phase transition for p = 0.8. On directed Barabási‐Albert we show that phase transition do not exist for Ising model with spin S = 1, 3/2 and 2.