Varela Aldas, José
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Varela Aldas, José
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Ambato
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josevarela@uti.edu.ec
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57192546163

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System Identification and Nonlinear Model Predictive Control with Collision Avoidance Applied in Hexacopters UAVs

2022 , Recalde, Luis , Guevara, B.S. , Carvajal, C.P. , Andaluz, V.H. , Varela Aldas, José , Gandolfo, D.C.

Accurate trajectory tracking is a critical property of unmanned aerial vehicles (UAVs) due to system nonlinearities, under-actuated properties and constraints. Specifically, the use of unmanned rotorcrafts with accuracy trajectory tracking controllers in dynamic environments has the potential to improve the fields of environment monitoring, safety, search and rescue, border surveillance, geology and mining, agriculture industry, and traffic control. Monitoring operations in dynamic environments produce significant complications with respect to accuracy and obstacles in the surrounding environment and, in many cases, it is difficult to perform even with state-of-the-art controllers. This work presents a nonlinear model predictive control (NMPC) with collision avoidance for hexacopters’ trajectory tracking in dynamic environments, as well as shows a comparative study between the accuracies of the Euler–Lagrange formulation and the dynamic mode decomposition (DMD) models in order to find the precise representation of the system dynamics. The proposed controller includes limits on the maneuverability velocities, system dynamics, obstacles and the tracking error in the optimization control problem (OCP). In order to show the good performance of this control proposal, computational simulations and real experiments were carried out using a six rotary-wind unmanned aerial vehicle (hexacopter—DJI MATRICE 600). The experimental results prove the good performance of the predictive scheme and its ability to regenerate the optimal control policy. Simulation results expand the proposed controller in simulating highly dynamic environments that showing the scalability of the controller. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

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IoT-Based Alternating Current Electrical Parameters Monitoring System

2022 , Varela Aldas, José , Silva, S , Palacios-Navarro, G.

Energy monitors are indispensable for achieving efficient electrical grids and even more so in the age of the Internet of Things (IoT), where electrical system data are monitored from anywhere in the world. This paper presents the development of a two-channel electrical parameter-monitoring system based on the M5 Stack Core2 kit. The acquisition of variables is done through PZEM 004T V3.0 sensors, and the data are sent to the ThingSpeak cloud database. Local readings are done through the LCD, and data re stored on a micro SD card. Remote monitoring is done through two applications, namely a web application and a mobile application, each designed for different purposes. To validate this proposal, a commercial device with IoT features (Gen 2 Vue Energy Monitor) is used, comparing the active power and active energy readings recorded continuously for 7 days. The results indicate an accuracy of up to 1.95% in power and 0.81% in energy, obtaining a low-cost compact product with multiple features. © 2022 by the authors.

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Virtual goniometer using 3 space mocap sensors for lower limbs evaluation

2020 , Buele, Jorge , Pilatásig, M. , Angueta, H. , Ruales, María Belén , Varela Aldas, José

The deterioration of motor skills in lower limbs represents a reduction in people’s quality of life. This paper presents a virtual goniometer developed by the 3 Space Mocap sensors and Unity 3D software. The system shows lower limbs angles in real-time. This system helps physiatrists determine the movements of hip and knee and was compared with a goniometer to corroborate the system performance. To validate this prototype, comparative tests are carried out present a standard deviation of 1.86° and 2.12° in the left hip and knee respectively. Therefore, it confirms to be a reliable proposal for physical evaluations of lower limbs. © Springer Nature Switzerland AG 2020.

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Movement Monitoring in Commercial Areas Using Internet of Things

2023 , Varela Aldas, José , Ruales, María Belén , Bastidas G.

The Internet of Things has been a trend in the last decade and is now found in countless applications, solving problems in almost any field. Specifically, in the commercial area, there is an effort to apply this technology to facilitate the control of services or processes. This work presents the movement monitoring of commercial areas. The proposal uses the ESP32 board that, using passive infrared sensors located perpendicular to each other, covers two areas of interest for commercial premises with multiple products. The collected data travel to the ThingSpeak Platform, where there are graphs with the states of the sensors, allowing identify the active area. The results present the motion state readings in the two areas, indicating the correct functioning of the system. Finally, we use a technology acceptance model to analyze this proposal, determining an acceptance of 69.6% that is not favorable for this proposal. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

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Virtual Reality applications based on activities of daily living (ADL) for cognitive diagnosis and rehabilitation

2022 , Buele, Jorge , Varela Aldas, José , Palacios-Navarro G.

Traditionally, screening tools are available to help diagnose a person's cognitive problem. Therefore, rehabilitation techniques are lab exercises that lack adequate ecological validity. In this paper, we propose to establish the projection of a methodology for the development of serious games based on activities of daily living (ADL). Both for real and immersive environments, to assess what provides better results when applied in healthy patients at first, but with a focus on those suffering from Alzheimer's disease. It is expected that when this research is completed, precedents will be established for the development of new proposals based on virtual environments. © 2022 IEEE.

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System for Monitoring and Warning of the Ultraviolet Radiation Index: A Study Case in Ecuador Elementary Schools

2020 , Buele, Jorge , Chango F.I. , Chango M.L.Á. , Santamaría M. , Varela Aldas, José

Solar ultraviolet (UV) radiation has increased in recent years due to ozone layer depletion and in Ecuador in particular, due to its geographical position and the height of its cities. Prolonged sun exposures in childhood increase the risk of causing malignant effects on the skin and eyes, such as squamous cell carcinoma, melanoma and cataracts. For this reason, this document describes the design of a device based on UV optical sensors that allows determining the existing radiation index. As a processing unit there is the Raspberry Pi 3B+ embedded board and to display the data physically there are LED panels. The storage of information is done through a database managed by MySQL and also implemented on the board. The levels of the ultraviolet radiation index (UVI) are presented through a graphical user interface (GUI) in real time, which also allows generating a report in a.csv file. Functional tests were carried out in the central courtyard of two educational units, to raise awareness among parents and authorities on the adoption of preventive measures that avoid possible damage to the skin of children when carrying out outdoor activities. © 2020, Springer Nature Switzerland AG.

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Facial recognition system for people with and without face mask in times of the covid-19 pandemic

2021 , Talahua J.S. , Buele, Jorge , Calvopina P. , Varela Aldas, José

In the face of the COVID-19 pandemic, the World Health Organization (WHO) declared the use of a face mask as a mandatory biosafety measure. This has caused problems in current facial recognition systems, motivating the development of this research. This manuscript describes the development of a system for recognizing people, even when they are using a face mask, from photographs. A classification model based on the MobileNetV2 architecture and the OpenCv's face detector is used. Thus, using these stages, it can be identified where the face is and it can be determined whether or not it is wearing a face mask. The FaceNet model is used as a feature extractor and a feedforward multilayer perceptron to perform facial recognition. For training the facial recognition models, a set of observations made up of 13,359 images is generated; 52.9% images with a face mask and 47.1% images without a face mask. The experimental results show that there is an accuracy of 99.65% in determining whether a person is wearing a mask or not. An accuracy of 99.52% is achieved in the facial recognition of 10 people with masks, while for facial recognition without masks, an accuracy of 99.96% is obtained. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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Prototype of a Low Cost Turbine for the Generation of Clean Energy in the Ecuadorian Amazon

2020 , Guáitara B. , Buele, Jorge , Salazar F.W. , Varela Aldas, José

Access to electricity supply in remote areas is limited, despite having wealth of other natural resources such as water. This document presents the design and construction of a scale electric generation system, taking advantage of the hydraulic energy produced by a constant flow of water flow. For this, the turbine design is described, which is based on the principles of Francis and Kaplan. In addition, the structural design made in CAD/CAM software and the actual implementation of the system are shown. To determine the generated electric potential, the electromagnetic analysis is performed based on the Maxwell-Faraday equation and the respective calculations. The validation of this proposal is determined by conducting experimental tests with balanced, unbalanced, series and parallel coils and with their implementation in a home. © 2020, Springer Nature Switzerland AG.

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Virtual environment application that complements the treatment of dyslexia (VEATD) in children

2020 , Buele, Jorge , López, V.M. , Varela Aldas, José , Soria, A. , Palacios-Navarro, G.

The educational disorders that children present at an early age can cause them to not fully develop throughout their lives. In this research work a 3D virtual system that allows the child who has been diagnosed with dyslexia to complement the exercises performed in a conventional therapy is described. To achieve this an application was developed, the app consists of two games (each with three levels of difficulty), and that are part of the rehabilitation program. In each of these games virtual objects are combined with auditory messages to provide the user with an immersive experience, and to train more than one sense at a time. In the first game task, the activity asks the children to correctly locate the syllables that compose a word and for the second activity the children will listen to a word, after the games asks the children to select the correct word. This tool has been tested by a group of children (eight), with ages ranging from 8 to 12 years old, whose development can be supervised at home by their parents, since it is an intuitive and easy to use interface. The results obtained are stored in a database and in this way the medical specialist can monitor the progress of the child throughout his treatment. For the validation of this proposal the SUS usability test was used. © Springer Nature Switzerland AG 2020.

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A Comparative Between S-Commerce and M-Commerce

2023 , Castillo Ledesma, Franklin Adrian , Varela Aldas, José , Oleas-Orozco J. , Soberón-López J.

The internet has contributed with the development of various economic sectors, one of the most important is the sale of products and services. This research aims to present two types of sales, that can be done online and through the use of social media, which can favor businesses in their growth. The objective of this work is to carry out an analysis of the sales that are made through social media and those made through a mobile application. The development of the mobile application was produced using Android Studio with its Kotlin language in conjunction with the MySql database manager. The methodology has been of a qualitative type, with data obtained through surveys carried out with the clients of the business that were the object of the initial study. Considerable results could be obtained in social media, since its development is easier and less expensive than developing your own mobile application for the business. Finally, surveys were carried out on the participating people to measure the level of acceptance of the tools used in the commercialization of the products, in results a summary of the acceptance per question is shown, with an average acceptance of 3.16/ 5 for the mobile application and 4.5/5 for the social network used to sell the products. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

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