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The objective of the present article is to provide a progress report on, and highlight, some ongoing efforts regarding the available techniques for the direct (i.e. not based on Monte Carlo simulations) prediction of the distribution of the forced response of turbomachinery bladed disks that exhibit small blade‐to‐blade variations in their structural properties (random mistuning). The focus of this effort is on the statistical distributions of the amplitudes of response of a typical blade at a given frequency (level 1), of the maximum responding blade on the disk at a given frequency (level 2), and finally of the maximum responding blade on the disk over a frequency sweep (level 3). When appropriate, emphasis will be placed on the reliability of these techniques as a function of the blade‐to‐blade coupling strength.

The purpose of this study is twofold: firstly, to investigate the effect of the infill value and build orientation on the fatigue behaviour of polylactic acid (PLA) specimens made by fused filament fabrication (FFF), also known as fused deposition modelling; and secondly, to model the fatigue behaviour of PLA specimens made by FFF and similar additive manufactured parts.

A new methodology based on filament characterisation, infill measuring, axial fatigue testing and fatigue strength normalisation is proposed and implemented. Sixty fatigue FFF specimens made of PLA were fabricated and evaluated using variable infill percentage and build orientation. On the other hand, fatigue modelling is based on the normalised stress amplitude and the fatigue life in terms of number of cycles. In addition, a probabilistic model was developed to predict the fatigue strength and life of FFF components.

The infill percentage and build orientation have a great influence on the fatigue behaviour of FFF components. The larger the infill percentage, the greater the fatigue strength and life. Regarding the build orientation, the specimens in the up-right orientation showed a much smaller fatigue strength and life than the specimens in the flat and on-edge orientations. Regarding the fatigue behaviour modelling, the proposed Weibull model can predict with an acceptable reliability the stress-life performance of PLA-FFF components.

This study has been limited to axial fatigue loading conditions along three different build orientations and only one type of material.

The results of this study are valuable to predict the fatigue behaviour of FFF parts that will work under variable loading conditions. The proposed model can help designers and manufacturer to reduce the need of experimental tests when designing and fabricating FFF components for fatigue conditions.

A fatigue study based on a novel experimental methodology that considers the variation of the FFF process parameters, the measurement of the real infill value and the normalisation of the results to be comparable with other studies is proposed. Furthermore, a new fatigue model able to predict the stress-life fatigue behaviour of PLA-FFF components considering variable process parameters is also proposed.

The purpose of this study is to determine the optimal shape of a one-sided elliptical composite material patch of an adhesively bonded repair of cracked metal plates under biaxial stress.

The approach consists on determining the patch topology and adhesive thickness that minimize the stress intensity factor and the bending moment caused by the asymmetry of the repair by applying a differential evolution algorithm with a selection phase using the Deb’s rules.

The results demonstrate that an elliptical patch of major axis length equal to the plate width, and minor axis length equal to the crack length, with a thin adhesive thickness, provides the highest stress intensity factor and bending moment reduction, maximizing the fatigue life of the repair.

The results are limited to linear elastic behavior of the cracked plate and a fully rigid bond between the cracked plate and the patch. The effectiveness of the repair was verified by theoretical calculation of the fatigue life, thus experimental validation is still needed.

The results of this work can be applied to experimental validations of the effectiveness of the elliptical one-side composite bonded repairs, avoiding and extensive number of experiments, and also, encourage maintainers to explore on this technique that is more economical and easier to apply, in comparison to other repair techniques. By following the patch geometry recommendations proposed herein, it is analytically predicted that the fatigue life may increase by as much as 27 times that of the unpatched plate.

Currently, there are no detailed studies that assess one-side patch repair procedures, which require consideration of the bending moment and biaxial stress state, and therefore, the optimal patch geometry and adhesive thickness are unknown.

This paper aims to present the Colombian Alejandro López Restrepo as a classic management thinker from the first half of the twentieth century and discuss his ideas in the light of Anglo-Saxon authors at that time and his contributions as a professor, manager and public servant.

Bibliographic material including López’s books and essays and their biography published by Mayor (2001) are reviewed to organize a new reading of López as a management thinker and practitioner.

Beyond several classical managerial thinkers, López reconceptualized scientific management with a critical discussion of classical economic theory using sociology and psychology to present a unique conception of work, enterprise and efficiency as a public service that gives sense to individual and social realization to face the future and create development.

Techniques as critical biography and interpretation of data have not been used, instead the aim to contribute to the literature of management history a Latin American’ thinker.

Including López as a classical management thinker can improve the study of management history. His life and ideas give new reflexive insight to understand the development of management in Colombia and serve to inspire administrators to seek improvements in society.

The paper offers a new approach toward studying Alejandro López beyond previous sociological work by Mayor (2001) with the discussion of the contributions in the lenses of managerial practices and theoretical insights at that time.

This study aims to present the climate change effect on soil moisture regimes in Mexico in a global 1.5°C warming scenario.

The soil moisture regimes were determined using the Newhall simulation model with the database of mean monthly precipitation and temperature at a scale of 1: 250,000 for the current scenario and with the climate change scenarios associated with a mean global temperature increase of 1.5°C, considering two Representative Concentration Pathways, 4.5 and 8.5 W/m² and three general models of atmospheric circulation, namely, GFDL, HADGEM and MPI. The different vegetation types of the country were related to the soil moisture regimes for current conditions and for climate change.

According to the HADGEM and MPI models, almost the entire country is predicted to undergo a considerable increase in soil moisture deficit, and part of the areas of each moisture regime will shift to the next drier regime. The GFDL model also predicts this trend but at smaller proportions.

The changes in soil moisture at the regional scale that reveal the impacts of climate change and indicate where these changes will occur are important elements of the knowledge concerning the vulnerability of soils to climate change. New cartography is available in Mexico.

The purpose of this paper is to analyse how solar energy is harnessed and implemented in Mexico. This paper presents a diachronic analysis of the divergent literature presented into the subject with the themes being divided substantially.

This paper used at least five methods in the identification of the studies with the first being the use of the SCImago Institution Ranking followed by the use of Scopus for journal evaluation. SCImago was used to determine the efficiency of the journals with the Newcastle Ottawa scale allowing for the evaluation of the different case study articles presented on Mexico. The fourth tool was a 21-item STROBE checklist after which the Web of Science was used to determine the authenticity levels of the identified articles.

The implementation of solar energy technologies is still novel in Mexico with private and public entities working together towards building sustainable options. In addition, it cites the divergent merits that might stem from the use of solar energy technologies.

A myriad of articles has been presented concerning solar energy in Mexico, but no attempt has been made to synthesize the evidence and arguments made in this significant body of research. The subsequent review is original with its findings being valuable for current and future research.

The purpose of this paper is to analyse the measures taken by the Mexican Government in relation to the country’s climate change and its management to improve it.

Much of the information which has guided this review was sourced from official documents referred to the climate change initiatives in Mexico, especially technical reports and working papers. The selection of literature was considered based on its recency, academic importance and veracity. The studies selected mainly ranged from 2001 to 2017.

This review finds that further research is required to assess Mexico’s climate change efforts objectively, which will help to ascertain if the nation’s plans and commitment are as ambitious and strong as the country claims.

Most of the literature considered in this review was sourced from official documents and has not been subject to extensive academic peer review to guarantee that national decision and policy making are based on reliable scientific knowledge.

Mexico is one of the first countries to introduce a law dedicated to climate change, and its inclusion of short-term climate pollutants in its National Climate Change Strategy makes it more ambitious than that of many other Latin American countries. However, literature on the subject is limited and fragmented.

The study aims to provide relevant information on the educational processes experienced by university students in Spain during the period of compulsory confinement. To this end, the key factors of the emergency educational model implemented by the country's universities have been analysed.

The study investigated, through qualitative, exploratory research and 30 in-depth interviews, how university students have lived the process of change to alternative forms of education during the crisis, what training experiences stand out and what factors related to virtual education they identify as relevant keys.

Participants usually focus on three main topics: (1) The impacts of changes in training development with regard to methodologies and forms of assessment; (2) The facilities and difficulties in this new modality of online training; and (3) The consequences of the crisis on higher education in the medium and long term.

Students participating in the study offer relevant and critical information on the adaptations developed by Spanish universities during the Coronavirus crisis. This information can be fundamental for the conscious decision making of the institutions, so that they can develop educational processes more adequate to the needs and possibilities of the university students in times of crisis.

Diversity is one of the main characteristics of modern societies. To be teachers and trainers, it is necessary to use all the tools to respond to students with diversified needs. Therefore, the main aim of this study is to review the scientific production in Web of Science (WOS) and SCOPUS of 1996-2019 on the application of Virtual reality in people with Autism Spectrum Disoders (ASD) for the improvement of social skills.

For this purpose, two databases have been used: The Web of Science (WOS) and SCOPUS from the advanced search tab. After applying the search terms, 267 documents were obtained which were analysed according to a series of indicators.

The results indicate that the period 2016-2019 was the most productive and that SCOPUS has a focus on conferences and WOS is intended for journals. Furthermore, in SCOPUS, there are journals with higher quartiles (Q1) than in WOS. The study shows the great importance of virtual reality in people with ASD and its recent dissemination.

Currently, to the best of the authors’ knowledge, there are no studies on the use of virtual reality in people with ASD using bibliometric indicators. The study allows us to know which databases publish higher quality research. Likewise, information can be obtained about the most productive centres and the most important authors on the subject.