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The research focused on analyzing the virtual environments’ elements and their influence on the English language’ significant learning in students aged 15 to 16 years of high school fifth year of an Educational Institution in the Ambato city, Ecuador. Current educational practices impose changes and challenges necessary for the improvement of the teaching-learning process, which networked applications become learning places such as: "Edmodo". The virtual environment’ main components analyzed are: content management, planning and mapping of the curriculum, participation and administration of students, communication and collaboration, communication in real time. On the other hand, the activities to generate meaningful learning must involve and support combinations of: active, constructive, intentional, authentic and cooperative learning. This information was collected through the survey technique, raised both towards the authorities, teachers and students. Subsequently, the statistical analysis of Chi square was used to detect significant results. Thus, these results showed that most of the students exhibit a lack of knowledge on virtual environments and consider that the use of this alternative educational pedagogical technology would help to improve the Meaningful Learning process in students.

In this research, intermediate calamagrostis vegetal fiber (FIC) combined samples were carried out in combination with polyester resin (RP), Aluminum Hydroxide (HA) and Magnesium Hydroxide (MH). The aim of this study is to determine inorganic flame-retardant effectiveness in the intermediate calamagrostis’ combustion rate reduction from Ecuador’s moorlands and possible forest fires’ control of this endemic plant species. The flammability index was obtained following the ISO 3795 standard; In addition, the contamination degree: Carbon Monoxide (CO) was determined, following the standard EPA 40 CFR, method 60 Annex A. The composite material was evaluated in a horizontal flammability chamber. Furthermore, the experimental design considered seven tests, one control and two flame retardants’ types. Aluminium Hydroxide and Magnesium Hydroxide accounted for three different concentrations at 3%, 6% and 9% percent each one. Thus, these flame retardants’ effectiveness was greater for Aluminium Hydroxides at all the proposed concentrations, while for Magnesium Hydroxide; its effectiveness was positive for a concentration of 9% only. The study determines that the best combination of materials are: 70% FIC, 21% PR, 9% HA, resulting in a combustion rate of 190.98 mm / min and self-extinguishing capacity. Finally, an average decrease of 50% in the generation of CO and the amount of smoke was determined.

One of the most popular methods for manufacturing new products is FDM (Fusion Deposition Modeling). In which two segments are established: industrial and desktop. The latter group has had notable growth in recent years. One of the disadvantages found in this method is its surface finish, which presents a remarkable roughness. In this research work, the correlation that exists in the printing configuration’ parameters and the resulting roughness analyzed by means of the ISO 4287-1997 standard will be analyzed. The configuration parameters to take into account are: layer height, printing speed. The materials to be analyzed are: PLA, PET-G, ASA, Wood Filament, TPU. Besides, the equipment used is a Prusa brand desktop printer with the manufacturer’s software. What is more, the acceleration, extruder temperature and bed recommended in the software are used for each material. Hence, the constant printing characteristics are: perimeter thickness, 10% infill, extrusion diameter 0.4 mm. The objects to be evaluated are printed and the roughness on the walls of the Z axis, base plane and upper plane is measured. This analysis was carried out by means of the correlation by the use of the analysis of variance ANOVA. The printing speed does not affect the resulting surface roughness in any plane, while the layer height only shows a significant correlation ( < 0.05) with the roughness of the lateral plane of the samples.

Esta investigación permite dar a conocer los riesgos físicos en las tareas de mantenimiento de una estación de radio base de telefonía celular. A pesar de que hasta la fecha las investigaciones realizadas anteriormente no presentan evidencia científica importante para indicar que estas radiaciones afectan al ser humano, estos análisis han determinado la existencia de límites de exposición a radiaciones no ionizantes, los cuales deben ser respetados por los trabajadores que realizan este tipo de trabajos. Las mediciones de densidad de potencia (s), densidad de campo eléctrico (e), densidad de campo magnético (H) realizadas para alturas (h) de 2 hasta 5 m en el lóbulo principal del emisor o antena donde existe la máxima ganancia determinaron un 32 % de los puntos medidos sobrepasan el límite permisible. Con estos valores se establecieron las distancias de seguridad y, por lo tanto, se determinó que: la altitud es inversamente proporcional a la densidad de campo magnético, eléctrico y de potencia.