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In this paper, a robust analysis of SO2 concentration measurements taken at the Belisario air quality monitoring station, Quito, Ecuador is carried out. The analyzed data contain 12 years of measurements, from January 2008 to December 2019. In addition, this set of measurements was decomposed into variables that represent each year, month, day of the week, and hour of the day in groups of two hours. For the analysis, classic, nonparametric and robust statistical methods were used, and the data were classified based on criteria established by the Quiteño Air Quality Index, taking confidence intervals into account. The results showed that the level of air pollution at the Belisario station due to the SO2 concentration is acceptable. In addition, the trend in the level of SO2 concentration decreased over the years studied, with a sharp drop from 2008 to 2012, then a small rise in 2013 and another fall until 2019, presenting decreasing oscillations that tend toward a desirable level of pollution. In this paper, it was shown that the air pollution at the Belisario station due to the concentration of SO2 in the last 12 years is not harmful to humans, with the measurement precision provided by robust statistical methods. Therefore, it can be concluded that the measures that have been taken by the Quito city council over the last few years are yielding good results.

This paper analyzes 12 years of tropospheric ozone (O3) concentration measurements using robust techniques. The measurements were taken at an air quality monitoring station called Belisario, which is in Quito, Ecuador; the data collection time period was 1 January 2008 to 31 December 2019, and the measurements were carried out using photometric O3 analyzers. Here, the measurement results were used to build variables that represented hours, days, months, and years, and were then classified and categorized. The index of air quality (IAQ) of the city was used to make the classifications, and robust and nonrobust confidence intervals were used to make the categorizations. Furthermore, robust analysis methods were compared with classical methods, nonparametric methods, and bootstrap-based methods. The results showed that the analysis using robust methods is better than the analysis using nonrobust methods, which are not immune to the influence of extreme observations. Using all of the aforementioned methods, confidence intervals were used to both establish and quantify differences between categories of the groups of variables under study. In addition, the central tendency and variability of the O3 concentration at Belisario station were exhaustively analyzed, concluding that said concentration was stable for years, highly variable for months and hours, and slightly changing between the days of the week. Additionally, according to the criteria established by the IAQ, it was shown that in Quito, the O3 concentration levels during the study period were not harmful to human health.

In this paper, a robust analysis of nitrogen dioxide (NO2) concentration measurements taken at Belisario station (Quito, Ecuador) was performed. The data used for the analysis constitute a set of measurements taken from 1 January 2008 to 31 December 2019. Furthermore, the analysis was carried out in a robust way, defining variables that represent years, months, days and hours, and classifying these variables based on estimates of the central tendency and dispersion of the data. The estimators used here were classic, nonparametric, based on a bootstrap method, and robust. Additionally, confidence intervals based on these estimators were built, and these intervals were used to categorize the variables under study. The results of this research showed that the NO2 concentration at Belisario station is not harmful to humans. Moreover, it was shown that this concentration tends to be stable across the years, changes slightly during the days of the week, and varies greatly when analyzed by months and hours of the day. Here, the precision provided by both nonparametric and robust statistical methods served to comprehensively proof the aforementioned. Finally, it can be concluded that the city of Quito is progressing on the right path in terms of improving air quality, because it has been shown that there is a decreasing tendency in the NO2 concentration across the years. In addition, according to the Quito Air Quality Index, most of the observations are in either the desirable level or acceptable level of air pollution, and the number of observations that are in the desirable level of air pollution increases across the years.

This paper presents a robust analysis of carbon monoxide (CO) concentration measurements conducted at the Belisario air-quality monitoring station (Quito, Ecuador). For the analysis, the data collected from 1 January 2008 to 31 December 2019 were considered. Additionally, each of the twelve years analyzed was considered as a random variable, and robust location and scale estimators were used to estimate the central tendency and dispersion of the data. Furthermore, classic, nonparametric, bootstrap, and robust confidence intervals were used to group the variables into categories. Then, differences between categories were quantified using confidence intervals and it was shown that the trend of CO concentration at the Belisario station in the last twelve years is downward. The latter was proven with the precision provided by both nonparametric and robust statistical methods. The results of the research work robustly proved that the CO concentration at Belisario station in the last twelve years is not considered a health risk, according to the criteria established by the Quito Air Quality Index.

In this article, robust confidence intervals for PM2.5 (particles with size less than or equal to 2.5 μ m ) concentration measurements performed in La Carolina Park, Quito, Ecuador, have been built. Different techniques have been applied for the construction of the confidence intervals, and routes around the park and through the middle of it have been used to build the confidence intervals and classify this urban park in accordance with categories established by the Quito air quality index. These intervals have been based on the following estimators: the mean and standard deviation, median and median absolute deviation, median and semi interquartile range, a -trimmed mean and Winsorized standard error of order a , location and scale estimators based on the Andrew’s wave, biweight location and scale estimators, and estimators based on the bootstrap- t method. The results of the classification of the park and its surrounding streets showed that, in terms of air pollution by PM2.5, the park is not at caution levels. The results of the classification of the routes that were followed through the park and its surrounding streets showed that, in terms of air pollution by PM2.5, these routes are at either desirable, acceptable or caution levels. Therefore, this urban park is actually removing or attenuating unwanted PM2.5 concentration measurements.

In this article, a robust statistical analysis of particulate matter (PM2.5) concentration measurements is carried out. Here, the region chosen for the study was the urban park La Carolina, which is one of the most important in Quito, Ecuador, and is located in the financial center of the city. This park is surrounded by avenues with high traffic, in which shopping centers, businesses, entertainment venues, and homes, among other things, can be found. Therefore, it is important to study air pollution in the region where this urban park is located, in order to contribute to the improvement of the quality of life in the area. The preliminary study presented in this article was focused on the robust estimation of both the central tendency and the dispersion of the PM2.5 concentration measurements carried out in the park and some surrounding streets. To this end, the following estimators were used: (i) for robust location estimation: α-trimmed mean, trimean, and median estimators; and (ii) for robust scale estimation: median absolute deviation, semi interquartile range, biweight midvariance, and estimators based on a subrange. In addition, nonparametric confidence intervals were established, and air pollution levels due to PM2.5 concentrations were classified according to categories established by the Quito Air Quality Index. According to these categories, the results of the analysis showed that neither the streets that border the park nor the park itself are at the Alert level. Finally, it can be said that La Carolina Park is fulfilling its function as an air pollution filter.

Peltogyne mexicana Martínez is a commercially attractive purple-hued hardwood tree of demographic, environmental and biogeographic rarity in southern Mexico. Despite P. mexicana’s status as a threatened species in Mexico, its populations are rarely managed and subject to open harvesting. Due to the limited number of P. mexicana studies that account for the influence of local tree extraction, we analyzed population-level parameters and community-level associations in two sites - one site called Tepehuaje with active P. mexicana extraction and another called Acahuizotla without extraction due to an ongoing P. mexicana moratorium. Using three 500 m2 plots per site, we characterized P. mexicana population size structure, abundance, spatial distribution, composition, and diversity of associated flora. In both sites, P. mexicana populations exhibited a type one size structure dominated by seedlings. Tepehuaje had 52% fewer saplings and juveniles and three times fewer adults when compared to the site without extraction. P. mexicana juvenile survival in Tepehuaje, a site with warmer climate and lower canopy cover, occurred mainly under trees with heavy foliage (including conspecifics). In Acahuizotla, a site with cooler climate and greater canopy cover, sapling and juvenile abundance was higher in open spaces and under small trees like Cascabela ovata. Although species richness was greater in Acahuizotla, species diversity was higher in Tepehuaje likely due to regularly opened gaps from artisanal logging that limited dominance of certain species. An importance value index (IVI) analysis based on dominance, abundance, and foliar coverage of associated P. mexicana plant communities revealed differences between Acahuizotla (Tetrapterys spp., followed by Plumeria rubra L) and Tepehuaje (Citharexylum affine D. Don, and Bauhinia ungulata L). All species associated with P. mexicana were found to be characteristic of tropical subdeciduous forests. Studying P. mexicana demography and ecology expands the limited knowledge we have of a rare, yet biologically important, species, and sheds light on local practices that can improve persistence.

The neocolonial undercurrent of internationalization that drives educational policies and standards, imposes a EEUUrocentric worldview and perspective of human development upon the global South. Beyond the discourse of international cooperation, this vision sustains what Quijano describes as the ‘coloniality of power’ that deepens inequalities between universities of the global North and South. In Latin America, there are various alternative educational projects, including indigenous universities that turn inwards toward rich pluriversal contexts, histories of resistance, and diverse tapestries of knowledge to address local problems and train youth to generate new horizons for ongoing indigenous and afro-mestizo social movements. This article is a reflective analytical account of our seven-year experience as volunteer educators at the Universidad Intercultural de los Pueblos del Sur (UNISUR) from an intercultural and decolonial feminist perspective. Founded in 2007 in southern Mexico, UNISUR was formed as a grassroots indigenous university of and for the original peoples of Guerrero state. Our account disrupts the hegemonic vision of an internationalized education that sustains racialized ‘colonialities of power’ and instead proclaims the right to self-determination, to the empowerment of women, and to an education based on principles of decolonial epistemic equity.

Se identifican elementos de análisis que justifican la necesidad de integrar los sistemas de control que emanan de los documentos normativos, nacionales y ramales del Ministerio de Educación Superior de Cuba y de la Contraloría General de la República -Ley 60/2011 y, en función de la estrategia y la estructura de la organización, mejorar la gestión docente. Se resalta el rol del eslabón de base en la gestión docente para la formación del profesional y la importancia del uso de instrumentos de control.

Beginning from the analysis of the invariant of the development of science and the productive process are established the criteria for the selection of the content in the subjects related to Natural Sciences in the formation of an engineer on the bases of inter-material relationship. Different tools for the elaboration of logic reds are presented as fundamental element for the interdisciplinary fulfillment of the organization and in the performance of the curricular project. Here, it is offered an interdisciplinary approach which tends to the integration of the engineering vision with science to a humanist approach in the study of factors which are held in the production process. This highlights the need to value epistemologically the application of the modular approach: the professional formation beginning from a narrower interaction between subject and the object professional transformation.

Having an accurate model of the power curve of a wind turbine allows us to better monitor its operation and planning of storage capacity. Since wind speed and direction is of a highly stochastic nature, the forecasting of the power generated by the wind turbine is of the same nature as well. In this paper, a method for obtaining a robust confidence band containing the power curve of a wind turbine under test conditions is presented. Here, the confidence band is bound by two curves which are estimated using parametric statistical inference techniques. However, the observations that are used for carrying out the statistical analysis are obtained by using the binning method, and in each bin, the outliers are eliminated by using a censorship process based on robust statistical techniques. Then, the observations that are not outliers are divided into observation sets. Finally, both the power curve of the wind turbine and the two curves that define the robust confidence band are estimated using each of the previously mentioned observation sets.