Centro de Investigación de Ciencias Humanas y de la Educación
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Effects of a dual intervention (motor and virtual reality-based cognitive) on cognition in patients with mild cognitive impairment: a single-blind, randomized controlled trial

2024 , Buele, Jorge , Avilés-Castillo, Fátima , Carolina Del-Valle-Soto , Varela Aldas, José , Guillermo Palacios-Navarro

Abstract Background The increase in cases of mild cognitive impairment (MCI) underlines the urgency of finding effective methods to slow its progression. Given the limited effectiveness of current pharmacological options to prevent or treat the early stages of this deterioration, non-pharmacological alternatives are especially relevant. Objective To assess the effectiveness of a cognitive-motor intervention based on immersive virtual reality (VR) that simulates an activity of daily living (ADL) on cognitive functions and its impact on depression and the ability to perform such activities in patients with MCI. Methods Thirty-four older adults (men, women) with MCI were randomized to the experimental group (n = 17; 75.41 ± 5.76) or control (n = 17; 77.35 ± 6.75) group. Both groups received motor training, through aerobic, balance and resistance activities in group. Subsequently, the experimental group received cognitive training based on VR, while the control group received traditional cognitive training. Cognitive functions, depression, and the ability to perform activities of daily living (ADLs) were assessed using the Spanish versions of the Montreal Cognitive Assessment (MoCA-S), the Short Geriatric Depression Scale (SGDS-S), and the of Instrumental Activities of Daily Living (IADL-S) before and after 6-week intervention (a total of twelve 40-minutes sessions). Results Between groups comparison did not reveal significant differences in either cognitive function or geriatric depression. The intragroup effect of cognitive function and geriatric depression was significant in both groups (p < 0.001), with large effect sizes. There was no statistically significant improvement in any of the groups when evaluating their performance in ADLs (control, p = 0.28; experimental, p = 0.46) as expected. The completion rate in the experimental group was higher (82.35%) compared to the control group (70.59%). Likewise, participants in the experimental group reached a higher level of difficulty in the application and needed less time to complete the task at each level. Conclusions The application of a dual intervention, through motor training prior to a cognitive task based on Immersive VR was shown to be a beneficial non-pharmacological strategy to improve cognitive functions and reduce depression in patients with MCI. Similarly, the control group benefited from such dual intervention with statistically significant improvements. Trial registration ClinicalTrials.gov NCT06313931; https://clinicaltrials.gov/study/NCT06313931.

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Quadcopters Control Using Online Dynamic Mode Decomposition

2023 , Guevara B.S. , Recalde L.F. , Varela Aldas, José , Gandolfo D.C. , Toibero J.M.

Over the past few years, unmanned aerial vehicles (UAVs) have gained popularity in a wide range of applications such as delivery services, inspection, and monitoring. However, for these applications to be safe and efficient, an accurate model of the UAV's dynamic is essential. In this article, the authors propose a novel control system for the DJI Matrice 100 quadcopter based on the online dynamic mode decomposition with control (DMDc) algorithm and iterative optimal estimation techniques. The online DMDc algorithm enables the identification of the system's dynamic, a critical requirement for an adaptive control. By decomposing the quadcopter's system into dynamic modes, the authors create a precise model of the system's behavior using a Hardware in the Loop (HiL) framework, which is used to design the control system based on inverse dynamics. The adaptive control system can adjust its parameters based on changes in the system's behavior, making it suitable for UAV operations in unpredictable environments. These results demonstrate that the proposed control system significantly improves performance in the presence of disturbances.The research contributes to the field of UAV control and highlights the potential of DMD and adaptive control techniques for enhancing the safety and efficiency of UAV operations. Copyright © 2023 The Authors.

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Voltammetric Electronic Tongues Applied to Classify Sucrose Samples Through Multivariate Analysis

2021 , Fuentes, E.M. , Varela Aldas, José , Verdú S. , Meló R.G. , Alcañiz M.

The aim of the present study was to classify samples of sugar with different concentrations through a Voltammetric Electronic tongues (VET), with a generic pulse sequence consisted of 22 pulses ranging from –1000 mV to + 1000 mV with a duration of 20 ms/pulse over different samples such as 1.25mM, 2.5mM, 5mM and 10mM, of sucrose concentration, these were measured 4 times each concentration and the test was developed 4 times, giving a total number of 506.880 data supervised learning algorithm using support vector machine was employed, choosing a linear function as a classifying element. In the training, 75% of the data was used to determine the coefficients of the classification function, and the remaining (25%) was used to evaluate the performance of the proposal. The results showed a concordance of more than 80% in the separation of sample, allowing to conclude as acceptable the performance of the classifier and the data acquired through the voltammetric tongue. © 2021, The Author(s), under exclusive license to Springer Nature Switzerland AG.

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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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Towards sustainable businesses in Latin America: The role of worker's Dark Triad personality traits

2023 , Afshar Jahanshahi A. , Mendoza M.I.R. , Juan Carlos Andrango Vicuña

Having sustainable businesses becomes priority for many Latin American countries these years. Socially responsible behaviors (SRBs) of employees in the workplace plays important roles in making businesses more sustainability oriented. The main aims of this research to identify those employees, which involve less in two types of SRBs: societal behaviors and sustainability-oriented behaviors at the workplace by considering their Dark Triad personality traits. By using survey-based data from 550 workers in Peru and Ecuador, we found a negative relationship between workers Dark Triad personality traits (Machiavilism and Psychopathy) and their socially responsible behaviors in the workplace. Furthermore, our results show that workers with higher level of Machiavilism and psychopathy has lower level of environmental concerns, which in turn reduce their intentions to involve in socially responsible behaviors in the workplace. Our study advances sustainable business research in Latin America by providing workers Machiavellianism and Psychopathy as a novel predictor of socially responsible behaviors of employees at the workplace. © 2023 ERP Environment and John Wiley & Sons Ltd.

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Development of Behavior Profile of Users with Visual Impairment

2020 , Guevara Maldonado, César Byron , Arias Flores, Hugo Patricio , Varela Aldas, José , Castillo Salazar, David Ricardo , Borja M. , Fierro-Saltos W. , Rivera R. , Hidalgo-Guijarro J. , Yandún-Velasteguí M.

The interaction of the user with visual impairment with assistive technologies, and in particular with screen readers, generates a group of actions and events during their navigation. These interactions are defined as behavioral patterns, which have a sequence that occurs at specific time slot. Understanding user behavior by analyzing their interaction with applications, in addition, details the characteristics, relationships, structures and functions of the sequence of actions in a specific application domain. The objective of this document is to find activity patterns from a set of commands used by the user, combining data mining and a Bayesian model. This model calculates the probability of the functions used with the screen reader and generates a behavior profile to improve the user experience. For this study, the screen reader JAWS version 2018, the Open Journal Systems platform version 3.0.1 and a computer with Windows 10 operating system were used. During the first phase, command history used by the user by interacting with the Open Journal Systems platform were collected. The result is that the accessibility of users with visual impairment to interact with the computer and its applications has been improved by applying this model. © Springer Nature Switzerland AG 2020.

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Twitter Mining for Multiclass Classification Events of Traffic and Pollution

2020 , Chamorro V. , Rivera R. , Varela Aldas, José , Castillo Salazar, David Ricardo , Borja Galeas, Carlos , Guevara Maldonado, César Byron , Arias Flores, Hugo Patricio , Fierro-Saltos W. , Hidalgo-Guijarro J. , Yandún-Velasteguí M.

During the last decade social media have generated tons of data, that is the primal information resource for multiple applications. Analyzing this information let us to discover almost immediately unusual situations, such as traffic jumps, traffic accidents, state of the roads, etc. This research proposes an approach for classifying pollution and traffic tweets automatically. Taking advantage of the information in tweets, it evaluates several machine learning supervised algorithms for text classification, where it determines that the support vector machine (SVM) algorithm achieves the highest accuracy value of 85,8% classifying events of traffic and not traffic. Furthermore, to determine the events that correspond to traffic or pollution we perform a multiclass classification. Where we obtain an accuracy of 78.9%. © 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 Environment for the Mashing and Boiling Process in Craft Beer Production

2023 , Pogo S.I. , Granizo J. , Andaluz V.H. , Varela Aldas, José

Process automation allows to increase production and improve the quality of craft products. This paper presents the implementation of closed-loop control algorithms for a mashing and brewing plant of craft beer. The proposed control scheme is implemented through the HIL technique, for which a virtual environment that simulates the behavior of the industrial process and a control card where the control algorithms are implemented are considered. To represent the behavior of the plant level and temperature processes, the mathematical model of each process is obtained, this model is used for the design of the control algo-rhythms, and the plant is modeled in 3D and incorporated into the graphics engine also has effects of realism together with been 3D in order to increase the level of realism to the process. For user interaction with the environment, an HMI type mantle center is incorporated to visualize and control the process manually, semi-automatically, and automatically, in order to test the control algorithms safely and avoid the risk of instrumentation damage or loss of real materials. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

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Between the hygiene and the salvation: Cognitive framework, metaphors and educative work of psychologists in Chilean schools. [Entre la higiene y la salvación: marcos cognitivos, metáforas y trabajo educativo de psicólogos en escuelas chilenas]

2019 , Díaz, D.P. , Kawada F.H. , Chávez R.C. , Morales P.G. , Espinoza S.L. , Díaz J.S

The purpose of the article is to understand the metaphors produced by psychologists to organize and define their work in Chilean schools. Considering that metaphor, rather than a rhetorical embellishment, is a linguistic figure that affects our ways of perceiving, thinking and acting in social reality, in this research, positioned from the Critical Discourse Studies, we examine its ideological potential to build and perpetuate particular visions of the world. According to this, we interviewed seven psychologists who work in schools classified as "emerging"within the framework of the Chilean Policy called Ley de Subvención Escolar Preferencial . We analyze discursively the information produced with a special emphasis on the rhetorical movements that revealed metaphors. Our main findings were two frameworks that join metaphors that psychologists use to explain their work in the schools: hygienist frame and salvation frame. Each one promotes particular conceptions of education, roles of school, the participation of the actors, and psychologist s work. Conflictly interconnected around a structural metaphor that conceives education as a commodity and school as a company, these frames are discussed from the interconnections between psychology and education in a context of educational neoliberalization and from the need to build alternative frames to market hegemony. © 2019 Universidad Pompeu Fabra. All rights reserved.

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