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The purpose of this paper is to present applications of the topological optimization method dealing with fluid dynamic problems in two- and three dimensions. The main goal is to develop a tool package able to optimize topology in realistic devices (e.g. inlet manifolds) considering the non-linear terms on Navier–Stokes equations.

Using an in-house Fortran code, a Galerkin stabilized finite element is implemented method to solve the three equation systems necessary for the topological optimization method: the direct problem, adjoint problem and topological derivative. The authors address the non-linearity in the equations using an iterative method. Different techniques to create holes into a two-dimensional discrete domain are analyzed.

One technique to create holes produces more accurate and robust results. The authors present several examples of applications in two- and three-dimensional components, which highlight the potential of this method in the optimization of fluid components.

The authors contribute to the methodology and design in engineering.

Engineering fluid flow systems are used in many different industrial applications, e.g. oil flow in pipes; air flow around an airplane wing; sailing submarines; blood flow in synthetic arteries; and thermal and fissure spreading problems. The aim of this work is to create an effective design tool for obtaining efficient engineering structures and devices.

The authors contribute by creating an application of the method to design a tridimensional realistic device, which can be essayed experimentally. Particularly, the authors apply the design tool to an inlet manifold.

This article investigates the impact of teleworking, especially concerning work intensity, during the Covid-19 pandemic, on the routine of women university professors in Brazil.

The authors collected data through a web-based survey disseminated through social media and sent e-mails to professors (addresses obtained from educational institutions’ public information), reaching 1,471 responses which were analyzed by correlation and multinomial logistic regression (MLR).

The authors find evidence to confirm all hypotheses tested at different levels. The professors who noticed increased workload during the pandemic are mostly from private higher education institutions (HEIs). The authors also demonstrate the impact of professional and family contexts and find a higher number of negative feelings and workplace correlates that influence the perception of working more.

This work problematizes the condition of women in Brazilian society, revealing the overload of work in the intersection between family, work, self-care, and other tasks. This study contributes to the literature exploring the home-office/telework in extreme periods, as is the case of the Covid-19 pandemic period.

Using an ecological model of child participation and drawing on newsletter data from schools across the United States of America (USA), this chapter statistically explores five state factors linked with school protests against gun violence: (1) children’s neighbourhood opportunity; (2) race/ethnicity; (3) voter preference for either a Republican or a Democratic president; (4) child participation policies; and (5) gun laws/violence/ownership. The chapter explores factors linked to both student participation in protests and student nonparticipation in protests that take place at their schools. Three factors were found to be associated with participation and nonparticipation: children’s neighbourhood opportunity, voters’ preference, and participation policies. Findings suggest that Democratic-voting states, mediated by education opportunity, predict the frequency of student protests against gun violence. In Republican-voting states, where education opportunity does not mediate the frequency of school protests, students still organised and participated in protests but to a lesser extent. In addition, states with high overall children’s neighbourhood opportunity and voting student education board members are highly likely to have non-protesting students in schools with protests. The chapter presents five conclusions from these results for the positive and negative exercise of child participation rights and considers what further multilevel explorations can be done to further test the framework employed for this analysis.

The Geography of Tourism in Spain is now at a par in terms of its scientific production with other European countries. Since the middle of the '80s the quality and volume of contributions is analogous to the rest of the European Union, although as a part of University Geography in Spain it has not achieved the level of dedication reached by other subjects considering the importance of tourist activities to the economy, the society and the territory of Spain. It could be said that the Geography of Tourism in Spain is in the international vanguard in dealing with Mediterranean coastal tourism, with the relationships between the residential real estate and tourism sectors and with aspects related to tourism and leisure in rural and protected areas.

The purpose of this paper is to investigate the relationship between corporate debt-like compensation and the value of excess cash holdings.

The sample comprises 876 US firms covered by ExecuComp over the period 2006-2013. The authors apply the valuation regression of Fama and French (1998) to examine the marginal value of excess cash as a function of CEO inside debt holdings.

This paper proposes one hypothesis. The results constitute evidence that the value of excess cash to shareholders declines as CEO inside debt increases. More interestingly, excess cash holdings contribute less to firm value when shareholders expect their value to be destroyed due to managers’ conservative behavior.

The sample comprises only US firms, owing to a lack of firms data from other countries. It would be interesting to conduct future research on an international sample.

This paper contributes to a deeper understanding of investor valuation of excess cash in the presence of CEO inside debt. The findings complement previous studies on US firms by confirming the existence of a relationship between the agency costs of debt and firm policy decisions.

This work is, to the best of the authors’ knowledge, the first to examine the relationship between debt-like compensation and excess cash valuation, and it supports the view that the conflict between shareholders and debtholders largely affects firm cash policy, and hence, cash valuation.

E' molto importante che in questo V° Congresso degli Esperti scientifici del turismo una sezione del lavoro sia dedicata all'insegnamento turistico perchè non v'è problema di carattere scientifico o sociale che possa ignorare la scuola, in quanto la scuola è l'unico organo che esprime ininterrottamente la forza vitale dei popoli: eterno organismo vivente, la scuola salva e afferma la continuità spirituale dei paesi, assorbendo ed equilibrando in essa lo spirito delle forme ideologiche e delle tecniche nuove imposte dai rivolgimenti e mutamenti perenni della società.

We examine whether the percentage of independent members sitting on the audit committee, in different institutional settings, impacts the market reaction (measured by the abnormal stock returns variance and the abnormal trading volume) to earnings announcements. For our sample composed of more than 7'600 earnings announcements made by European firms from 15 countries between 2006 and 2014, we find that the market reactions to earnings announcements are significantly larger when the audit committee is more independent in countries with weak institutional setting. Our results generally hold after controlling for numerous methodological issues. We conclude that more independent audit committees are substitutes for weak institutions to increase the credibility of earnings announcements. Our results should be of great interest for European regulators who recently introduced new requirements for public firms regarding audit committees’ independence.

This study aims to examine the association between Not in Employment, Education, or Training (NEET) status and a set of individual and household socioeconomic factors, including potential gender-based variations, for young people aged 15–34 years in Cameroon and Chad.

Using data from the 2021 Survey on Youths’ Transition to the Labour Market in Francophone Africa, logistic regressions were conducted to identify the determinants of NEET status, and the multivariate decomposition for nonlinear response models was employed to examine gender disparities in the likelihood of being NEET.

In Cameroon, the likelihood of being NEET is linked to factors such as age, being female, being in a couple, having dependent children, financial difficulties and urban residency. In Chad, NEET status is associated with higher education, age, being female, being in a couple and having dependent children, but decreases with secondary education, technical education and balancing work and study. Gender disparities in NEET status are largely explained by individual characteristics, accounting for 56.16% of the disparity in Cameroon and 73.72% in Chad. The main contributors in Cameroon are higher education, marital status and having children, while in Chad they are secondary and technical education, studying STEM, age, marital status and having children.

This paper makes two key contributions: first, it is the pioneering study on the determinants of entering the NEET category in sub-Saharan Africa, focusing on individual characteristics; second, it offers the first comprehensive decomposition of factors driving gender disparities in the likelihood of being NEET.

The impact of diet quality on mental health has gained strong ground. However, most studies on this relationship were performed before COVID-19, a pandemic that was accompanied by high levels of psychological stress. Stress disturbs normal physiology, which makes studying diet quality and mental health under high stress a necessity. In addition, COVID-19 has been associated with disturbances in sleep and has increased the prevalence of mental health issues in women more than in men. Therefore, the purpose of this study was to assess food group consumption and sleep during different stages of the pandemic in relation to mental distress among men and women. Secondary data collected from adults 18 years or older between September 2018 and November 2021 was analysed. Temporal stages were divided into pre-COVID-19 (as a baseline), during the lockdown, and after the ease of restriction (two periods of different psychological stress levels). Regression analyses using a Difference-in-Difference (DID) event study or a Dynamic DID modelling were used. COVID-19 seemed to have a modulatory effect on food groups and mental health. The pandemic appeared to have either magnified the negative impact of certain food groups or changed the tolerance threshold for the beneficial ones. Across the board, women’s moods exhibited higher sensitivity to several food groups. COVID-19, a period of high psychological stress, differentially altered the impact of food on the mood of men and women; which proposes the need to further evaluate diet quality and mood under stressful conditions.

The dry construction techniques, widely used in past centuries have seen a renewed interest in the last few years. This is due to different reasons such as the new user’s needs for high quality at low cost, the shortage of traditional skilled labor, the need to reduce delivery times and the rising costs of initiating a fabrication plant.

Dry construction methods regard the building site as the place of assembly. The quality of the finish products, are guaranteed by a factory controlled production process and reduction to a minimum of on-site work. The building, designed by “unconnected boxes” becomes an “active machine”, capable of ensuring maximum performance for the user. Finally the design of an “open building system” also consists of a set of rules to allow creation of various solutions.

The complexity of this modus operandi increases progressively if the intervention is carried out in small historic centres. Therefore, this research aims at presenting a method of work that uses dry construction systems and that has been developed to intervene in the historic contexts damaged by the earthquake that struck the Abruzzo region on April 6, 2009.

This method develops a process that aimes at the rehabilitation of the buildings but also at improving their energy behavior while respecting, at the same time, the vernacular values. It is based on a “case by case” approach that starts from an analysis of the context and its local construction techniques, taking into account the peculiarities of each location. The results of this method have been applied to a small village located in the province of L'Aquila called Santa Maria del Ponte.