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Faltung equations (closed cycle type) have a wide range of biological applications, nonetheless, they are poorly studied. We use a Volterra‐Kostitzin model (which is a Faltung equation) to study the dynamics of a certain species, where the integral term represents a residual action. The complexity of resolution of this non‐linear equation using classical numeric methods is here solved with the Adomian decomposition method. Our method provides the same graphic solution as others do, such as the numeric method Miladie. However, the decomposition method of Adomian has the advantage that neither time nor space are considered discontinuous and that it gives an analytical solution with a reliable approximation.

In this paper the authors aim to show the advantages of using the decomposition method introduced by Adomian to solve Emden's equation, a classical non‐linear equation that appears in the study of the thermal behaviour of a spherical cloud and of the gravitational potential of a polytropic fluid at hydrostatic equilibrium.

In their work, the authors first review Emden's equation and its possible solutions using the Frobenius and power series methods; then, Adomian polynomials are introduced. Afterwards, Emden's equation is solved using Adomian's decomposition method and, finally, they conclude with a comparison of the solution given by Adomian's method with the solution obtained by the other methods, for certain cases where the exact solution is known.

Solving Emden's equation for n in the interval [0, 5] is very interesting for several scientific applications, such as astronomy. However, the exact solution is known only for n=0, n=1 and n=5. The experiments show that Adomian's method achieves an approximate solution which overlaps with the exact solution when n=0, and that coincides with the Taylor expansion of the exact solutions for n=1 and n=5. As a result, the authors obtained quite satisfactory results from their proposal.

The main classical methods for obtaining approximate solutions of Emden's equation have serious computational drawbacks. The authors make a new, efficient numerical implementation for solving this equation, constructing iteratively the Adomian polynomials, which leads to a solution of Emden's equation that extends the range of variation of parameter n compared to the solutions given by both the Frobenius and the power series methods.

The paper presents a techno-economic analysis of the electromechanical equipment of traditional vertical axis water mills (VAWMs) to help investors, mill owners and engineers to preliminary estimate related benefits and costs of a VAWM repowering.

Two sustainable repowering solutions were examined with the additional aim to preserve the original status and aesthetics of a VAWM: the use of a vertical axis water wheel (VAWW) and a vertical axis impulse turbine. The analysis was applied to a database of 714 VAWMs in Basilicata (Italy), with known head and flow.

Expeditious equations were proposed for both solutions to determine: (1) a suitable diameter as a function of the flow rate; (2) the costs of the electromechanical equipment; (3) achievable power. The common operating hydraulic range of a VAWM (head and flow) was also identified. Reality checks on the obtained results are shown, in particular by examining two Spanish case studies and the available literature. The power generated by the impulse turbine (Turgo type) is twice that of a VAWW, but it is one order of magnitude more expensive. Therefore, the impulse turbine should be used for higher power requirements (>3 kW), or when the electricity is delivered to the grid, maximizing the long-term profit.

Since there is not enough evidence about the achievable performance and cost of a VAWM repowering, this work provides expeditious tools for their evaluation.

The purpose of this paper is to compare the practices of continuous improvement that are applied in medium and large manufacturing and service companies in two Latin American countries. At the same time, benefits and barriers experienced by these companies with regard to sustainability of continuous improvement are explored.

In order to generate a comparative study between two Latin American countries, interviews were conducted with managers linked to continuous improvement in medium and large companies in the State of Puebla and the Metropolitan District of Quito, which are important areas in Mexico and Ecuador, respectively. Data were collected by means of document analysis, semi-structured interviews, and direct observation.

Companies in both countries identify the use of various techniques and/or tools for continuous improvement. The results of the empirical evidence show how the impact of the application of the techniques has been beneficial in economic and human terms. Thus, the exploratory study has permitted the identification of the drivers and inhibitors in the maintenance of continuous improvement.

The research is based on only two areas of the Latin American countries: Mexico and Ecuador. Their results can therefore not be generalized. The approach is applied in a specific environment, namely, the State of Puebla and the Metropolitan District of Quito. This study incorporates the perception of managers, directors, and/or supervisors involved in continuous improvement processes.

This paper seeks to provide analytical input. The study is of great interest to researchers, managers, consultants, and professionals linked to projects of continuous improvement who wish to incorporate continuous improvement practices which are sustainable over time. A new managerial behavior is the basis of continuous improvement, where the training and development of the human resource increases the commitment to achieve organizational changes.

This research makes an empirical contribution to the literature through the understanding of practices of continuous improvement in a Latin American context, highlighting the factors that improve or impede the process of continuous improvement. Particularly in Mexico and Ecuador, the empirical evidence on this subject is still scarce despite the existence of theoretical academic literature.

This study aims to identify the current state, the emergent research clusters, the key research topics and the configuration of collaboration in scientific production related to the market value of soccer players.

This article analyzes 52 articles published between 1985 and 2021 and from the Scopus and WoS databases.

The subject is of growing interest both in academic and practical areas. A variable that frequently appears as a determinant of market value is crowd wisdom. The largest cluster related to the co-citation level shows that the main issues about soccer player market value are player performance, team performance, and the determinants of the superstar formation. Spain and Germany stand out as essential countries both in literary production and citation rate. The network of collaborations is still low.

This study is supported by databases being constantly updated, resulting in continuous variation in the number of indexed journals. Consequently, a bibliometric analysis regarding an emergent topic can, in fewer years, be subject to essential variations. Another limitation is that it has analyzed a particular topic using the most influential databases, and the global perspective could be improved with the incorporation of other different databases. Data regarding collaborations could be helpful for investigations or policies that propose to approach the topic supported by specialized groups. This study offers the possibility for future researchers to extend the databases used, the level of analysis, or focus on specific topics or variables affecting the soccer player market value.

This study contributes to knowing the current state of the soccer player market value research. Studies on such topics are relatively limited concerning the literature review.

This study aims to contribute to the professional competency approach in Education for Sustainability (ES) from the perspective of complexity and to the assessment of these competencies.

A qualitative research process was used, which consisted of two main phases: a documentary analysis of the internationally accepted frameworks about professional competencies in ES and complexity and a case study. The context was the Learning Camp of Cistercian Monasteries (Catalonia, Spain), and two educators participated in this camp.

The main outcomes are: a framework of professional competencies in ES from a complexity perspective, called CESC, and a rubric, as an assessment tool for professional competences in ES.

Based on the results, the author’s can state that this research is a contribution to the ES competency approach and it rectifies the lack of assessment tools in this area. The CESC is a theoretical contribution that facilitates educators’ development of ES competencies based on complexity. The design of the rubric with a high level of applicability and transferability is a methodological contribution which facilitates the assessment of these competencies by educators, as individuals, and educational teams. Related to the case study, several guidelines are proposed regarding the need for educator training to advance in the mobilisation of competencies in ES.

The aspirations at the 2021 World Congress for Justice WITH Children [WC] were lofty: ‘nothing about children without children’. Then a dose of reality kicked in. Children's live participation at the WC was almost as rare as sightings of white tigers in the wild. While several youths aged 18–25 had live speaking roles at the WC, their placement at the small table meant few would hear them.

In this Chapter, four Child and Youth Advisory Board [CYAB] members discuss why it matters that children and youth receive a seat at the big table. Children and youth offer the ‘lived experiences’ of young persons, which adults cannot possibly duplicate. Given the post-hegemonic character of youth organisations, the youth themselves are the ones best suited to use these experiences to analyse the child justice system and to develop policy goals germane to the best interests of the current generation of youth. To facilitate the youth contribution from the ground floor up, the CYAB members call upon adults to serve as intergenerational partners who resist the temptation to discipline the form and content of the youth's ideas. Along these lines, this Chapter itself is designed to let the youth voices resonate.

This chapter explores how the irruption of plastic materials in contemporary society, in the same way that it facilitated a wide range of human activities, eventually degenerated into a global danger through the contamination of rivers and seas, damaging the human food chain. In doing so, the historical background of this situation has been outlined. Moreover, the countries and areas at present that have polluting plastic substances and those that can be most easily recycled is highlighted. It should be noted that it is precisely in the area of recyclability where most hopes have been placed to counteract plastic contamination aimed at avoiding single-use plastic products. Subsequently, the different positions adopted by the members of society on this problem have been described and, by way of example, the state of the situation in a specific country, Spain, has been summarised.

The COVID-19 pandemic has disrupted the ‘real’ world and substantially impacted the virtual world and thus the Internet ecosystem. It has caused a significant exogenous shock that offers a wealth of natural experiments and produced new data about broadband, clouds, and the Internet in times of crisis. In this chapter, we characterise and evaluate the evolving impact of the global COVID-19 crisis on traffic patterns and loads and the impact of those on Internet performance from multiple perspectives. While we place a particular focus on deriving insights into how we can better respond to crises and better plan for the post-COVID-19 ‘new normal’, we analyse the impact on and the responses by different actors of the Internet ecosystem across different jurisdictions. With a focus on the USA and Europe, we examine the responses of both public and private actors, with the latter including content and cloud providers, content delivery networks, and Internet service providers (ISPs). This chapter makes two contributions: first, we derive lessons learned for a future post-COVID-19 world to inform non-networking spheres and policy-making; second, the insights gained assist the networking community in better planning for the future.