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This article aims to study a model of flame propagation in a nonhomogeneous medium with a p-Laplacian operator. The intention with such operator is to model the effects of slow and fast diffusion, that can appear in a nonhomogeneous media, depending on the pressure driven conditions. In addition, the authors introduce a general form in the reaction term, that introduces the flame chemical kinetics.

To introduce the governing equations, the authors depart from previously reported models in flame propagation, but the authors consider a new modeling approach based on a p-Laplacian operator.

The authors provide evidences of regularity and uniqueness of solutions. Afterward, the authors introduce profiles of stationary solutions based on the definition of a Hamiltonian for the newly discussed model. Eventually, the authors obtain exponential profiles solutions with the help of a scaling, that transforms the model into a nonlinear Hamilton–Jacobi equation.

The new model has not been previously reported in the literature. The authors consider that the mathematical properties of a p-laplacian (in particular the property known as finite propagation) is of inherent interest to model pressure drive flames with slow or fast diffusion. Indeed, the authors’ approach has the value of providing an operator that can fit better to model flame propagation. In addition, the authors introduce a general form of chemical kinetics, to make the authors’ model further general.

The objective of this study is to model the propagating front in the interaction of gases in an aircraft fuel tank. To this end, we introduce a nonlinear parabolic operator, for which solutions are shown to be regular.

The authors provide an analytical expression for the propagating front, that shifts any combination of oxygen and nitrogen, in the tank airspace, into a safe condition to avoid potential explosions. The analytical exercise is validated with a real flight.

According to the flight test data, the safe condition, of maximum 7% of oxygen, is given for a time t = 45.2 min since the beginning of the flight, while according to our analysis, such a safe level is obtained for t = 41.42 min. For other safe levels of oxygen, the error between the analytical assessment and the flight data was observed to be below 10%.

The interaction of gases in a fuel tank has been little explored in the literature. Our value consists of introducing a set of nonlinear partial differential equations to increase the accuracy in modeling the interaction of gasses, which has been typically done via algebraic equations.

To address the challenges of the agricultural sector, innovation is necessary. This study aims to focus on knowledge circulation as a basis to facilitate innovation in viticulture in the context of climate change.

We have conducted interviews with viticulture stakeholders in Central Spain (Madrid region) on their perceptions and concerns about climate change, knowledge on practices to mitigate its effects on this crop and their relationship with each other for knowledge exchange. A map showing the knowledge nodes and their relationships with other stakeholders has been drawn based on the answers obtained.

Winegrowers have already noticed the effects of climate change, and they are changing some agricultural practices. Drip irrigation was the most frequently mentioned option to minimize these effects. The map of knowledge identifies the main nodes in the information flow. Results also highlight different approaches to climate change and interesting nuances in the maps of knowledge among winegrowers with and without winery.

This paper is focused on the Madrid region, a territory that is still consolidating its wine sector at the economic and marketing levels. We understand that regions with more consolidated or stronger sectors involve maps of knowledge more complex than that obtained in this study.

Showing the nodes of knowledge, as well as the weaknesses and strengths of the information circuit in the wine sector in the Madrid region, is very relevant to developing strategies aimed at supporting innovation in this sector. From a practical point of view, strategies for knowledge generation and circulation are only one part of the innovation process – policies for financial and technical support are key complementary measures.

Identification of key agents in the innovation process in the wine sector is essential to foster innovation processes. Ultimately, this will lead to more efficient adaptation to new challenges in the sector.

The Agriculture Knowledge and Innovation Systems (AKIS) approach has a consolidated theoretical framework that pays great attention to knowledge flows, but specific studies are needed to capture the reality of AKIS by sector and by region.

This study aims to examine the performance of environmental, social and governance (ESG) equity indices in Latin America (LA), evaluating their risk-return characteristics in comparison to conventional benchmark indices.

Using a quantitative empirical approach, the authors analyze ESG equity indices from Brazil, Mexico, Chile, Peru and Colombia, employing metrics such as Sharpe, Sortino and Omega ratios to measure risk-adjusted returns. Regression analysis is employed to assess the replicability of ESG indices by benchmark indices. Monte Carlo simulations are conducted to explore the potential increase in risk-adjusted returns when ESG equity indices are incorporated into portfolios.

The study addresses critical questions for investors: Can ESG indices outperform their benchmarks? Can these ESG indices be replicated by benchmark counterparts? Do ESG equity indices enhance portfolio diversification? The findings reveal that investing in ESG indices has the potential to enhance risk-adjusted returns and portfolio diversification.

While this study focuses on various LA economies, it’s important to note variations in currency and volatility.

For investors in LA, this study highlights the importance of considering ESG indices as part of their investment strategies. While not all ESG indices outperform conventional ones, some may improve diversification and risk-adjusted performance. Investors should carefully assess market-specific conditions and national factors when making investment decisions.

The primary contribution of this study is its focus on LA countries in the examination of diverse portfolios. The research provides valuable insights into the performance of ESG indices in this region compared to conventional benchmark indices. This approach addresses an important gap in the existing literature and offers a more comprehensive perspective on ESG investing and portfolio diversification.

Se examina el rendimiento de los índices-ESG en América Latina (AL), evaluando sus características de riesgo y retorno en comparación con los índices convencionales.

Utilizando un enfoque cuantitativo, analizamos los índices-ESG de Brasil, México, Chile, Perú y Colombia, empleando ratios de Sharpe, Sortino y Omega para medir los rendimientos ajustados al riesgo. Se utiliza análisis de regresión para evaluar la replicabilidad de los índices-ESG por parte de los índices de referencia. Se realizan simulaciones de Monte-Carlo para explorar el aumento en los rendimientos ajustados al riesgo cuando se incorporan los índices-ESG en las carteras.

El estudio aborda preguntas críticas: ¿Pueden los índices-ESG superar a sus índices de referencia? ¿Pueden estos índices-ESG ser replicados por sus contrapartes de referencia? ¿Mejoran los índices-ESG la diversificación de las carteras? Los hallazgos revelan que la inversión en índices-ESG tiene el potential de mejorar los rendimientos y la diversificación de las carteras de inversión.

Aunque este estudio se centra en diversas economías de AL, es importante tener en cuenta variaciones en moneda y volatilidad.

La principal contribución de este estudio radica en su enfoque en países de AL en el examen de carteras diversas; ofrece valiosos conocimientos sobre el rendimiento de los índices-ESG en esta región en comparación con los índices convencionales.

Heritage landmarks and historical values often coexist with places and regions of remarkable environmental and landscape wealth. This article studies their capacity to generate global understanding of their territory through the creation of cultural routes. The proposed methodology is verified through the study of the defensive features of the ancient Nasrid Kingdom, the last Islamic territory in the Iberian Peninsula from the thirteenth to the fifteenth century, which shaped the Spanish region known as the Kingdom of Granada until the nineteenth century.

To assist in the proposal of new routes, a precise collection of physical data (topography, landmarks, resources, population centres …), existing public paths and protected natural sites was carried out. Those cultural routes relevant to the area of study were also selected and mapped through GIS. A set of indicators prioritised through an analytic hierarchy process (AHP) have evaluated the proposed itineraries.

The methodology enables the integral evaluation of parameters such as natural heritage, existing paths networks, defensive architectural heritage (watchtowers), existing cultural routes or proximity to basic services. The methodology's application allows an index to be obtained that quantifies the global implications of these parameters in the design of new itineraries. This leads to the development of a network with its own narrative that provides a historical, environmental and cultural meaning.

Watchtowers in this region have previously been studied as isolated and locally relevant architectural features. This work studies them from an overall perspective, considering each tower as a piece of a complex defensive and territorial system. Cultural routes arise from this joint interpretation as tools to restore and highlight the interrelationship between architectural heritage and territory and people.

The main objective of this study was to establish a model of competitiveness factors to measure the value of construction companies adequately.

A theoretical model of four main factors was developed, and they include human capital, ethical values, process innovation and financing. Information was collected from 18 construction companies in the city of Metropolitan Lima, collecting information on each of these factors. Through an analysis of the principal components, the weighting of each factor about the competitiveness of a construction company was determined.

The cost of person-hours, the cost of equipment to execute work, and the cost of materials used are the strongest indicators to measure the competitiveness of a construction company. On the other hand, the number of employees holding university degrees and the number of master builders holding technical degrees in the human capital factor also have a moderate weight in determining the competitiveness value of a company. The indicator of work delivered within the deadline also moderately affects competitiveness. Finally, the monthly debt payment indicator has a very small effect on the company’s competitiveness.

In conclusion, this study provides evidence of a competitiveness model with highly related factors on human capital, process innovation and ethical values as the most important in measuring competitiveness.

El objetivo principal de la investigación fue establecer un modelo de factores de competitividad para medir adecuadamente el valor de las empresas constructoras.

Se desarrolló un modelo teórico de cuatro factores principales, que incluyen el capital humano, los valores éticos, la innovación de procesos y el financiamiento. Se recolectó información de 18 empresas constructoras de la ciudad de Lima Metropolitana, recolectando información de cada uno de estos factores. A través de un análisis de componentes principales se determinó la ponderación de cada uno de ellos sobre la competitividad de una empresa constructora.

El costo de horas hombre, el costo de los equipos para ejecutar obras y el costo de material utilizado son los indicadores más fuertes para medir la competitividad de una empresa constructora. Por otro lado, la cantidad de empleados con títulos universitarios y la cantidad de maestros de obra con título técnico del factor de capital humano también tienen un peso moderado en la determinación del valor de competitividad de una empresa. El indicador de obras entregadas dentro de plazo también tiene un efecto moderado sobre la competitividad. Finalmente, el indicador de pago mensual de la deuda tiene un efecto muy pequeño sobre la competitividad de la empresa.

En conclusión, el estudio proporciona evidencia de un modelo de competitividad con factores altamente relacionados sobre el capital humano, la innovación de procesos y los valores éticos como los más importantes a la hora de medir la competitividad.

The job satisfaction of university graduates can serve as an indicator of success in their professional development. At the same time, it can be a measure of higher education systems’ effectiveness. The purpose is to assess the relationship of university graduates’ socio-demographic characteristics, aspects of their degree program, experiences in the labor market and current working conditions and their job satisfaction.

The data were collected from a survey conducted at 11 Chilean universities with 534 graduates. An ordinal logistic regression model was fit to calculate job satisfaction probabilities for different graduate profiles.

The results show that sex, field of study, gross salary and horizontal match are related to graduates’ job satisfaction. Men and graduates in education and humanities are more likely to report being satisfied with their current job. Those graduates receiving higher salaries and those who are horizontally well-matched report higher levels of job satisfaction.

This study contributes to expanding knowledge about the job satisfaction of university graduates. Specifically, based on the results obtained, it introduces the idea of aspiration fulfillment as a possible determinant of job satisfaction in different fields of study. This can serve as a starting point for research that delves into differentiated expectations for graduates from different disciplines.

Mexico is a large, culturally and linguistically diverse country. More than half of its population lives below the poverty line, a fifth is of indigenous origin, and 5% have a disability. This chapter offers a brief description of the general characteristics of the country and the legislative changes toward inclusion and presents the status and progress toward the 2030 Agenda educational goals toward inclusive education. Although efforts have been made to improve the quality of education and inclusion, the country's complexities: poverty, cultural diversity, and political adjustments, among others, have held back progress, as will be explained in this chapter.