Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Great efforts have been focused on finding ways to reduce energy consumption, since energy production is currently one of the major atmospheric pollutants. Thus, one strategy that seems to be effective is the implementation of Phase Change Materials (PCM), which due to their high latent heat can store a significant amount of energy. From this arises the objective of evaluating different phase change materials to determine their influence in improving the internal comfort of buildings, and that they do not negatively impact the environment. A literature review is carried out on the application of phase change materials as a passive element in building construction and the energy improvements it provides. The methodologies used in the simulations and experiments carried out in other investigations are detailed, as well as the description of the phase change materials studied. The evaluation criteria used to analyse the energetic behavior of the phase change materials are identified, and their energetic performance is described. Finally, the energy performance of five phase change materials is evaluated, under the climate of Panama City, by means of a simulation performed in DesignBuilder, based on the same performance indicators previously established, from which it is obtained that the phase change material PCM1 is the one that presents the best performance.

The possibility of producing electricity using clean technologies in the energy sector with zero polluting emissions that impact the environment, make renewable energy an attraction for humanity, meeting sustainable development goals, national energy plans and continuous improvement of the environment. This article presents the design of a 5MW power photovoltaic solar plant, where the technical and climatological parameters for its design were verified. We check the calculations with design equations simulating in the PVsyst program, where we compare the results of energy produced using the same climatic data and obtaining results with high similarity. In addition, we simulated with two climatic data additional to the one used in the design, to verify how much the energy production varies using other climatic resources, identifying that if there is influence of using different climatic data in photovoltaic solar plant desing. With this article we provide a new proposal for renewable technological designs and references for the design of photovoltaic solar plants in Panama, as well as the parameters that influence their energy production.

Milk provides essential nutrients and is an important source of dietary energy, high-quality protein, and fat. It contributes considerably to the necessary intake of nutrients such as calcium, magnesium, selenium, riboflavin, vitamin B12 and pantothenic acid. The consumption of this food can represent differences in the quality of the diets of people without access to adequate nutrition, especially among children. The composition of milk varies according to the incidence of multiple factors such as breed, lactation time, feeding, genetics, climatic condition, health status and stress of the animals, etc. The quality and safety of raw cow's milk can be affected by different reasons, microorganisms, chemical residues and other contaminants, which significantly affects public health. The increase of microorganisms in milk causes significant losses. Currently, there is very little or no publication or reference at the national level that indicates a quality characterization of raw cow's milk according to its physicochemical, or microbiological condition. However, the few existing studies show conditions that require further study and monitoring to consider the general state of the country's dairy herds. From the above, it is clear the need to carry out research, development and innovation (R & D & i) studies, which make it possible to establish the quality conditions of the milk produced in the country and correlate this condition with the internationally established quality parameters.

The expansion and dominance growth of Information and Communication Technologies (ITC) and the COVID -19 pandemic have established a climate of change and reinvention of traditional government structures, creating a pathway for a new generation of modernized public services or e-governments. This paper aims to present an Integrated Disaster Risk Management (IDRM) system and the methodology for the implementation of action plans for each potential risk. The main contribution of this case study lies on a relational model based on a computer platform that captures the evolution of each risk according to the levels of probability and severity. The model is a comprehensive and integrated approach that focuses on the underlying conditions of disasters (hazard and vulnerability) and emphasizes multilevel, multidimensional, and multidisciplinary coordination among the parties involved, using dashboard tools as data visualization for decision making and citizen inclusion in those decisions.

Different investigations have been developed over the years, and experimental research takes time to collect the information. Considering this, the objective of this research is to carry out a literature review of the strategies adopted by countries with tropical climates to achieve energy and water efficiency, as well as the comfort of the occupants to evaluate the performance of these techniques for each tropical climate type (i.e., tropical rainforest, tropical monsoon, tropical savanna, and subtropical). A methodology is presented using keywords and exclusion criteria for the best selection of articles. Time is saved by searching for information on low consumption strategies, types of buildings, and techniques implemented in each country. A summary of each experimental investigation is made. Results showed that it is possible to apply different techniques to the same type of building and have the savings of interest (water, energy, or comfort) without limiting it to a specific technique. Some tropical climates tend to use only one type of savings, such as comfort and others use energy and water. The experimental studies presented a relevant saving for passive design strategies in the following order: 1- 62.22% applying natural ventilation, water wall and stack flue, 2- 41% and 43% applying daylighting and glazing. 3- 35% applying wall insulation. For low consumption techniques: 1-14.31% and a 32.30% Remote Control extension device and 2-19% applying semitransparent photovoltaic glazing. This article is a resource that can be used by anyone interested in experimental studies in tropical climates.

The objective of this narrative review is to analyze the literature related to stress and its generating sources in aviation. As well as knowing, the measures that are being implemented in the area to reduce human errors in air accidents. Work stress is a growing public health problem in developing countries. Aviation-related professions tend to suffer from job stress and other psychological conditions, due to multiple factors. International aviation organizations have implemented detailed protocols to try to reduce the human factor in air accidents. The most widely used protocol is Crew Resource Management, which contributes to the proper use of machines and human resources. In conclusion, the responsibilities of aviation professionals, not only with themselves and with the institution for which they work, but also with the passengers they transport, cause them increased stress. Therefore, it is important to provide these professionals with effective psychological therapies so that they recognize how to reduce their stress levels. In addition, an approach from occupational health public policies is required to treat work stress, especially in high-risk activities such as aviation.

This paper presents an optimal location and sizing of distributed generation with active power injection in radial distribution systems, obtaining an optimum power flow through the particle swarm optimization algorithm (PSO). The proposed purposes are to minimize losses and improve the profile of voltages, fulfilling an objective function of minimizing costs. The restrictions used are balance of powers, voltage margins and power injection limits of the distributed generation. The analysis was carried out in the IEEE 15 nodes and IEEE 33 nodes radial distribution systems, and the implementation was developed in MATLAB mathematical software. The methodology used also allowed to improve the indexes of quality conditions such as the average voltage deviation and the maximum voltage deviation. The results obtained show that the method used makes a location and dimensioning of distributed generation able to minimize losses, improve voltage levels and all at the lowest possible cost.

The lemon (Citrus aurantifolia) stands out as one of the abundant sources of vitamin C (ascorbic acid). However, the availability of this vitamin can be significantly reduced during the industrial processing of the lemon by the action of temperature, among other variables. The objective of this work is to evaluate the kinetics of the degradation of ascorbic acid in lemon nectar, for temperature-time relationships: 65ºC, 75ºC, 85ºC and 95ºC at 5, 10, 15 and 20 min, using the iodometric titration method. The juice was characterized in terms of pH and Brix degrees. It was determined that the concentration of ascorbic acid in the juice of Citrus aurantifolia was reduced around 40% with respect to its initial concentration and it was found that it follows a kinetic of order one for all temperatures studied. The results of this research can lead to improve the stability of ascorbic acid in lemon derivatives.

Utilizar la construcción física de un prototipo como herramienta educativa no es una propuesta nueva, aunque puede ser innovadora en el contexto actual de renovación conceptual vinculado al desarrollo sustentable. En la Escuela de Arquitectura de Sevilla existe una gran tradición investigadora en materia de sustentabilidad, pero poco extrapolada a la enseñanza. También es necesaria una mejora significativa de la educación desde el ámbito metodológico. En este sentido, los concursos proporcionan una oportunidad que define una situación potencialmente afortunada para la innovación educativa. Partiendo de esta base, la presente investigación tiene como objetivo comprobar cómo la construcción de un prototipo a escala real, como estrategia metodológica educativa activa, de la mano de una metodología de diseño bioclimático consolidada en dicha escuela de arquitectura, permite lograr grandes resultados tanto en términos educativos como bioclimáticos. La metodología educativa empleada aúna las siguientes directrices: el taller como ámbito integrador para el aprendizaje arquitectónico; la construcción de un prototipo como situación educativa que trasciende lo arquitectónico; la conceptualización de los nuevos retos marcados por la sustentabilidad y su aplicación práctica y efectiva al proyecto, diseño y construcción arquitectónicos. Todas herramientas puestas en valor dan respuesta efectiva a las carencias actualmente detectadas e interiorizadas del aprendizaje-enseñanza y, por tanto, del quehacer arquitectónico.

O documento a seguir apresenta o procedimento de validação de propostas de otimização para um jardim de infância de tipologia compacta, de acordo com diretrizes de projeto bioclimáticas passivas, por meio de modelos de simulação dinâmica física calibrados com medições in situ. O objetivo é verificar os parâmetros de área envidraçada (Av), absortância solar média ponderada (alfa promedio) e área total de envolvente (Aenvolvente) usados como dados de entrada para obter correlações de Fatores de Envidraçamento (Fv), em uma ferramenta para estimar áreas envidraçadas ideais orientadas a integrar o conforto térmico e visual no desenho de espaços educacionais, no clima Muito Quente e Úmido da Região Nordeste da Argentina. Como resultado, conseguiu-se uma redução nas necessidades de resfriamento de até 72% no mês de novembro, o mês mais desfavorável para a atividade escolar, ao baixar a absortância solar das superfícies externas para 0,25, com uma razão de área envidraçada por área de piso de 17%, o que permitiu melhorias notáveis na distribuição espacial da luz natural, um recurso fundamental para o desenvolvimento integral das crianças no nível pré-escolar.