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Copyright of Educación XX1 is the property of Editorial UNED and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Contextualization: Currently, the knowledge of natural phenomena associated with the preservation of the systems is of interest both for researchers in the natural sciences, and for the environmental authorities in charge of decision- making on resource management. In this sense, work has been carried out on the interpretation and prediction of different physical phenomena such as erosion, to create scenarios that allow strengthening the response criteria for the conservation of the natural capital of the soil. Knowledge gap: The ability to predict the phenomenon of erosion is limited on many occasions due to the quantity and variability of the parameters and variables that are related to erosion; besides that, in many cases, a high computational processing is required to achieve that they are associated with each other. Purpose: The aim is to implement a machine learning model as an alternative tool for complex modeling and erosion prediction. Methodology: In this study, a model is developed from the training of the non-parametric Random Forest method through supervised learning, to predict erosion occurrences in the Rio Grande basin, considering the variables that have previously been used in other methods to model this phenomenon. Results and conclusions: The results showed a capacity to predict erosion in the basin with an approximate precision of 77%, so this method can be applied to obtain fast and reliable predictions. In addition, it was found that the variables used in the RUSLE model mainly explain the occurrence or not of erosion. The great importance of the temperature variable introduced in the model is also surprising. [ABSTRACT FROM AUTHOR]

Copyright of Anuario Turismo y Sociedad is the property of Universidad Externado de Colombia, Facultad de Empresas Turísticas y Hoteleras and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista CEA is the property of Revista CEA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Natural disasters, such as river overflows, extreme droughts, natural forest fires are more frequently observed in Argentina. Faced with these catastrophes, efficient management is essential to make quick decisions to minimize damage, which is a latent concern in local and regional governments and in the scientific community. In Argentina, the Paraná River basin represents a strategic resource in itself, as it encompasses the greatest fluvial, ecological wealth and large urban centers. However, the extreme events that characterize the dynamics of the wetlands affect the urban centers located near them. The presence of aquatic vegetation (free or rooted) masks the flooded areas, hiding the first signs of flooding, making the monitoring and rapid detection of these areas difficult. In this work, optical satellite images and machine learning models were used to classify the different land covers in wetlands of the Paraná river system. The focus was on environments where free water and aquatic marsh vegetation coexist, characteristic of the metropolitan region of the city of Santa Fe, and considering the technical limitations of decision-making agencies. Therefore, the Sentinel-2 (S2) mission images were used to train and evaluate different machine learning algorithms. All bands of S2 images were used, unifying the spatial resolution to 10 m. The results indicated that the coastal aerosol bands (B1) and two mid-infrared bands (B11 and B12) provide the most information for the identification of the samples. Moreover, the random forest method showed the best performance for the aquatic vegetation class, which was of primary interest for this work. [ABSTRACT FROM AUTHOR]

Copyright of Revista Cubana de Ciencias Informáticas is the property of Universidad de las Ciencias Informaticas (UCI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Ciencias Sociales (13159518) is the property of Revista de Ciencias Sociales de la Universidad del Zulia Venezuela and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: The objective was to apply models based on machine learning techniques to support the early diagnosis of diabetes mellitus, using environmental, social, economic and health data variables, without dependence on clinical sample collection. Methodology: Data from 10,889 users affiliated with the subsidized health system in the southwestern area of Colombia, diagnosed with hypertension and grouped into users without (74.3%) and with (25.7%) diabetes mellitus, were used. Supervised models were trained using k-nearest neighbors, decision trees, and random forests, as well as ensemble-based models, applied to the database before and after balancing the number of cases in each diagnostic group. The performance of the algorithms was evaluated by dividing the database into training and test data (70/30, respectively), and metrics of accuracy, sensitivity, specificity, and area under the curve were used. Results: Sensitivity values increased significantly when using balanced data, going from maximum values of 17.1% (unbalanced data) to values as high as 57.4% (balanced data). The highest value of area under the curve (0.61) was obtained with the ensemble models, by applying a balance in the amount of data for each group and by coding the categorical variables. The variables with the greatest weight were associated with hereditary aspects (24.65%) and with the ethnic group (5.59%), in addition to visual difficulty, low water consumption, a diet low in fruits and vegetables, and the consumption of salt and sugar. Conclusions: Although predictive models, using people's socioeconomic and environmental information, emerge as a tool for the early diagnosis of diabetes mellitus, their predictive capacity still needs to be improved. [ABSTRACT FROM AUTHOR]

This article presents the calculation of the sdg 11.3.1 and 11.7.1 indicators in Colombia, integrating statistical and geospatial information, as essential sources to achieve a robust and territorially disaggregated measurement. Based on the processes defined by un-Habitat, it develops a methodology with a geospatial emphasis, supported by the processing of satellite images through the Random Forest supervised classification algorithm, to obtain the metrics required in the calculation of the two indicators, such as built-up areas, urban land consumption, and open spaces, together with integrated analysis of statistical information. The sdg 11.3.1 indicator for the 2015-2020 period was calculated for 63 cities, whose national value of 0.43 highlights that efficient land use is made in the country, while sdg 11.7.1 for the year 2018 was calculated in a representative sample of nine cities, which indicates that at the national level 33.2 % of built areas are allocated to open spaces for public use. These results make the country a regional benchmark in the monitoring of the sdgs, highlighting the possibility of updating the results in the future, thanks to automated processing in the cloud using scripts developments. [ABSTRACT FROM AUTHOR]

Copyright of Revista Técnica Energía is the property of Centro Nacional de Control de Energia CENACE and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Investigación e Innovación en Ingenierías is the property of Universidad Simon Bolivar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work presents applications of the Backward Seismic Analysis (BSA) method for steel storage tanks using a data base of more than 382 steel storage tanks in operation during large subductive earthquakes: Valdivia 1960, Central Chile 1985, Tocopilla 2007, El Maule 2010, Alaska 1964, and others in the United States between 1933 and 1995 (subductive and cortical). It has been recorded that most of the steel storage tanks without anchor systems have failed during large earthquakes. These have been designed with the standards API 650-E, AWWA-D100, and NZSEE, which propose similar procedures for estimating seismic forces, but with different design methods. During different conferences, the causes of the failures were evaluated, concluding that the tanks were designed mainly with the API 650-E code and were unanchored. Moreover, the design codes employed do not consider relevant aspects that condition the seismic response of steel storage tanks. This work develops a prediction model based on the historical information already described, which is capable of efficiently predicting if a steel storage tank will suffer any failures during an earthquake. Various algorithms were evaluated, finding that the Random Forest method exhibits the best results. The results obtained in the prediction of steel storage tank failures reach more than 90% efficiency in most of the evaluated scenarios. [ABSTRACT FROM AUTHOR]

Objective: Small intracranial aneurysms are increasingly being detected; however, a prediction model for their rupture is rare. Random forest modeling was used to predict the rupture status of small middle cerebral artery (MCA) aneurysms with morphological features. Methods: From January 2009 to June 2020, we retrospectively reviewed patients with small MCA aneurysms (<7mm). The aneurysms were randomly split into training (70%) and internal validation (30%) cohorts. Additional independent datasets were used for the external validation of 78 small MCA aneurysms from another four hospitals. Aneurysm morphology was determined using computed tomography angiography (CTA). Prediction models were developed using the random forest and multivariate logistic regression. Results: A total of 426 consecutive patients with 454 small MCA aneurysms (<7mm) were included. A multivariate logistic regression analysis showed that size ratio (SR), aspect ratio (AR), and daughter dome were associated with aneurysm rupture, whereas aneurysm angle and multiplicity were inversely associated with aneurysm rupture. The areas under the receiver operating characteristic (ROC) curves (AUCs) of random forest models using the five independent risk factors in the training, internal validation, and external validation cohorts were 0.922, 0.889, and 0.92, respectively. The randomforest model outperformed the logistic regression model (p = 0.048). A nomogram was developed to assess the rupture of small MCA aneurysms. Conclusion: Randomforestmodeling is a good tool for evaluating the rupture status of small MCA aneurysms and may be considered for the management of small aneurysms. [ABSTRACT FROM AUTHOR]

In this work we consider 148 semiochemicals reported for the family Scarabaeidae, whose chemical structure was characterized using a set of 200 molecular descriptors from five different classes. The selection of the most discriminating descriptors was carried out with three different techniques: Principal Component Analysis, for each class of descriptors, Random Forests and Boruta-Shap, applied to the total of descriptors. Although the three techniques are conceptually different, they select a similar number of descriptors from each class. We proposed a combination of machine learning techniques to search for a structural pattern in the set of semiochemicals and then perform their classification. The pattern was established from the high belonging of a subset of these metabolites to the groups that were obtained by a grouping method based on fuzzy C-means logic; the discovered pattern corresponds to the biosynthetic pathway by which they are obtained biologically. This first classification was corroborated with Kohonen's self-organizing maps. To classify those semiochemicals whose belonging to a biosynthetic pathway was not clearly defined, we built two models of Multilayer Perceptrons which had an acceptable performance. [ABSTRACT FROM AUTHOR]

Copyright of Boletin de Geologia is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a document classification service that allows multiple client (multi-tenant) document management systems to provide greater confidence and credibility regarding the document types assigned to documents uploaded by users. The research was carried out through the phases of CRISP-DM, where two document representation models were evaluated (bags of words with cumulative n-grams and BERT, which was recently proposed by Google) and five machine learning techniques (multilayer perceptron, random forests, k-nearest neighbors, decision trees, and naïve bayes). The experiments were carried out with data from two organizations, and the best results were obtained by multilayer perceptron, random forests, and k-nearest neighbors, which showed very similar results regarding general accuracy and recall by class. The results are not conclusive with respect to the ability to offer the service to multiple clients with a single model, since this also depends on their documents and document types. Therefore, a service is offered which is based on a microservices architecture that allows each organization to create its own model, monitor its performance in production, and update it when performance is not adequate. [ABSTRACT FROM AUTHOR]

Performance tests are crucial to measure the quality of software developments, since they allow identifying aspects to be improved in order to achieve customer satisfaction. The objective of this research was to identify the optimal Machine Learning technique to predict whether or not a software development meets the customer's acceptance criteria. A dataset with information obtained from web services performance tests and the F1-score quality metric were used. This paper concludes that, although the Random Forest technique obtained the best score, it is not correct to state that it is the best Machine Learning technique; the quantity and quality of the data used in the training play a very important role, as well as an adequate processing of the information. [ABSTRACT FROM AUTHOR]

Changes in land use and land cover lead to environmental consequences of various kinds. Digital classification of remotely sensed images is a powerful tool to assess the degree of environmental transformation due to anthropogenic factors. The aim of this work is to develop a working scheme based on remote sensing techniques and digital image classification to obtain cartographies of land use and land cover in the Segura Hydrographic Demarcation, for the period between 1986 and 2019. For this purpose, the Random Forest supervised classification algorithm has been used and the spectral bands of Landsat 5, 7 and 8 images, and four normalised indices derived from these, have been used as predictor variables. Although the overall accuracy achieved indicates that there is room for improvement in the model fit, the classifications obtained are considered reliable. With regard to the land uses and land covers obtained after the classification process, a decrease in forest use and an increase in agricultural uses, area covered by scrubland, bare soil and greenhouses can be observed. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Shrimp sector in Ecuador is nowadays one of the fastest-growing non-oil sectors towards the international market. In despite of this growth, to our knowledge most of the little producers of shrimps in Ecuador take important operational decisions based upon empirical knowledge, without considering historical data nor any scientific tool. In this work we implement and compare state-of-the-art statistical learning techniques for the prediction of shrimp harvest (in pounds) for a little shrimp farm located in Tenguel, Guayaquil-Ecuador. For this study we used historical information collected by the farm biologist. The data was organized and put into a digital format by the authors. Data from n=35 past harvests, corresponding to 7 cycles of production, were used to train the models. We then made predictions of shrimp harvest for the next two production cycles. We compare Multiple Linear Regression by means of ordinary least squares, CART Regression Tree, Random Forests, Multivariate Adaptive Regression Splines (MARS) and Support Vector Machines (SVM). In our analysis, MARS with no interaction terms allowed, Linear Regression with best subset variable selection and SVM with linear Kernel gave the lowest prediction error estimate by Cross Validation. Their good predictive performance was confirmed with good predictions on the next two production cycles. The use of statistical techniques can be of great help to improve predictions and therefore operational processes of small shrimp farms. [ABSTRACT FROM AUTHOR]

The purpose of this article is to make a brief introduction to five advanced machine learning prediction methods which may be useful for the development of prospective studies: logistic regression, support vector machines, gradient powered machines, random forests and neural networks. In addition, it is explained what methodology can be carried out to ensure robustness and validate these prediction models. As an example, it is presented how the use of these methods allowed to identify the most important financial variables to predict the development of innovation activities in Colombian SMEs. The results of the use of these methods may allow generating short and medium-term forecasts that serve to facilitate prospective studies with broader methods, such as the construction of scenarios, with the purpose of generating evidence-based proposals as a roadmap for long-term planning and public policy. [ABSTRACT FROM AUTHOR]

Copyright of Revista Biológico Agropecuaria Tuxpan is the property of Revista Biologico Agropecuaria Tuxpan and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)