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Dual-process theories postulate that both reflective and automatic processes regulate health behavior. Further research is required to test the basic postulates of dual-process theories. We investigated the direct associations and moderating effect between automatic processes and multiple indicators of reflective processes on various levels of physical activity and sedentary behavior assessed using accelerometry in adults who were not participating in regular physical exercise programs. This cross-sectional study included 257 adults. Each participant completed a computerized test for automatic associations, a set of questions assessing reflective processes, a seven-day assessment using accelerometers to determine their levels of physical activity and sedentary behavior. The results showed a direct relationship between perceived benefits (B = 15.90, p = 0.043), perceived cons (B = -12.81, p = 0.034), decisional intention (B = -0.07, p = 0.049) with light physical activity, and self-efficacy with daily steps (B = 485.71, p = 0.008). There was a positive association between intention strength and daily steps when implicit associations favored physical activity (b = 623.36, LLCI = 79.09, ULCI = 1167.62, p = 0.025); a negative association between self-efficacy and sedentary behavior when implicit associations favored sedentary behavior (b = -25.73, LLCI = -49.77, ULCI = -1.70, p = 0.035); and a positive association between intention strength and sedentary behavior when implicit associations favored physical activity (b = 34.18, LLCI = 8.81, ULCI = 59.56, p = 0.008). These findings underscore the importance of considering the interplay between reflective and automatic processes in shaping movement behavior.

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Currently, remote laboratories have gained relevance in engineering education as tools to support active learning, experimentation, and motivation of students. Nonetheless, the costs and issues regarding their implementation and deployment limit the access of the students and educators to their advantages and features such as technical and educational. In this line, this study describes a fully open-source remote laboratory in hardware and software for education in automatic control systems employing Raspberry Pi and Python language with an approximate cost of USD 461. Even, by changing some components, the cost can be reduced to USD 420 or less. To illustrate the functionalities of the laboratory, we proposed a low-cost tank control system with its respective instrumentation, signal conditioning, identification, and control, which are exposed in this document. However, other experiments can be easily scalable and adaptable to the remote laboratory. Concerning the interface of the laboratory, we designed a complete user-friendly web interface with real-time video for the users to perform the different activities in automatic control such as identification or controller implementation through the programming language Python. The instructions to build and replicate the hardware and software are indicated in the open repositories provided for the project as well as in this paper. Our intention with this project is to offer a complete low-cost and open-source remote laboratory that can be adapted and used for the students, educators, and stakeholders to learn, experiment, and teach in the field of automatic control systems.

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This work is focused on the multilevel control of the population confinement in the city of Buenos Aires and its surroundings due to the pandemic generated by the COVID-19 outbreak. The model used here is known as SEIRD and two objectives are sought: a time-varying identification of the infection rate and the inclusion of a controller. A control differential equation has been added to regulate the transitions between confinement and normal life, according to five different levels. The plasma treatment from recovered patients has also been considered in the control algorithm. Using the proposed strategy the ICU occupancy is reduced, and as a consequence, the number of deaths is also decreased.

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Resumen Se presenta una revisión conceptual generalizada de los conformadores de entrada de sistemas de control como herramientas para eliminar vibraciones en la salida de los sistemas. Se desarrollan los diferentes tipos de conformadores como versiones mejoradas de Posicast, el conformador original. Luego se presentan las aplicaciones de Posicast en el desarrollo de sistemas electrónicos, específicamente, en circuitos de potencia y en circuitos microelectrónicos.

Abstract This work is a generalized conceptual revision of the control system input shapers. The input shapers are used to eliminate vibrations at the output of the systems. The different types of shapers are developed as improved versions of Posicast, or the original shaper. Then, Posicast applications are presented in the development of electronic systems, specifically in power circuits and microelectronic circuits.

Resumo Uma revisão conceitual generalizada dos formadores de entrada dos sistemas de controle é apresentada. Os formadores de entrada são usados para eliminar vibrações na saída dos sistemas. Os diferentes tipos de formadores são desenvolvidos como versões melhoradas do Posicast, o shaper original. Em seguida, as aplicações da Posicast são apresentadas no desenvolvimento de sistemas eletrônicos, especificamente em circuitos de potência e circuitos microeletrônicos.

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Abstract Introduction: Postural control in individuals with HTLV-1-associated myelopathy or tropical spastic paraparesis (HAM/TSP) is usually compromised, which increases the risk of falls, makes it difficult to perform activities of daily living, and impairs the quality of life. The profile of the center of gravity oscillations in this population is unknown and may aid in clinical follow-up and research. Objective: To compare the stabilometric values between HAM/TSP and uninfected individuals and verify the existence of correlations between stabilometric variables and the Berg Balance Scale (BBS). Method: A cross-sectional observational study was performed with infected individuals, classified as defined and likely (WHO criteria), compared to accompanying persons and seronegative relatives. A baropodometry platform (Footwork®) was used to obtain the oscillation values of the body's center of gravity in total oscillation area (TOA), anterior-posterior oscillation (APO) and lateral oscillation (LO). Mean values were correlated with BBS by Spearman's Correlation (5% alpha). Approved by the ethical committee of Escola Bahiana de Medicina e Saúde Pública under Opinion 49634815.2.0000.5628. Results: An asymmetric distribution of all the stabilometric variables analyzed in the HAM/TSP population was found, different from the uninfected group (p < 0.05). It was also possible to verify strong to moderate and inverse correlations between the variables of center of gravity oscillation with the scores obtained in BBS, especially for TOA and LO. Conclusion: People with HAM/TSP presented higher values for the center of gravity oscillations and these were correlated with the BBS in the balance evaluation.

Resumo Introdução: o controle postural em indivíduos com mielopatia associada ao HTLV-1 ou paraparesia espástica tropical (HAM/TSP) é geralmente comprometido, o que aumenta o risco de quedas, dificulta a realização de atividades de vida diária e prejudica a qualidade de vida. O perfil das oscilações do centro de gravidade nesta população é desconhecido e pode auxiliar no acompanhamento clínico e na pesquisa. Objetivo: comparar os valores estabilométricos entre pessoas com HAM/TSP e não infectados, e verificar a existência de correlações entre variáveis estabilométricas e a Escala de Equilíbrio Berg (EEB). Método: foi realizado um estudo observacional transversal com indivíduos infectados, classificados como definidos e prováveis (critérios da OMS), comparados com acompanhantes e familiares soronegativos. Uma plataforma de baropodometria (Footwork®) foi utilizada para obter os valores de oscilação do centro de gravidade do corpo em área de oscilação total (AOT), oscilação anteroposterior (OAP) e oscilação laterolateral (OLL). Os valores médios foram correlacionados com a BBS pela Correlação de Spearman (alfa 5%). Aprovado pelo Comitê de Ética da Escola Bahiana de Medicina e Saúde Pública sob o CAAE 49634815.2.0000.5628. Resultados: encontrou-se distribuição assimétrica de todas as variáveis estabilométricas analisadas na população com HAM/TSP, diferentes do grupo de não infectados (p < 0,05). Também foi possível verificar correlações de forte a moderada e inversas entre as variáveis de oscilação do centro de gravidade com os escores obtidos na EEB, especialmente para AOT e OLL. Conclusão: Pessoas com HAM/TSP apresentaram valores maiores para as oscilações do centro de gravidade e estas foram correlacionadas com a EEB na avaliação do equilíbrio.

Resumen Introducción: El control postural en individuos con mielopatía asociada al HTLV-1 o paraparesia espástica tropical (HAM/TSP) suele estar comprometido, lo que aumenta el riesgo de caídas, les dificulta en las actividades de la vida diaria y perjudica su calidad de vida. Conocer el perfil de las oscilaciones del centro de gravedad en esta población puede ayudar en el seguimiento clínico y la investigación. Objetivo: Comparar los valores estabilométricos entre personas con HAM/TSP y personas no infectadas, y verificar la existencia de correlaciones entre las variables estabilométricas y la Escala de Equilibrio de Berg (BBS). Método: Se realizó un estudio observacional transversal con individuos infectados, clasificados como definidos y probables (criterios de la OMS), comparados a acompañantes y familiares seronegativos. Se utilizó una plataforma de baropodometría (Footwork®) para obtener los valores de oscilación del centro de gravedad del cuerpo en el área de oscilación total (AOT), oscilación antero-posterior (OAP) y oscilación lateral-lateral (OLL). Los valores medios se correlacionaron con la BBS por la correlación de Spearman (alfa 5%). Estudio aprobado por el Comité de Ética de la Escuela Bahiana de Medicina y Salud Pública bajo CAAE 49634815.2.0000.5628. Resultados: Se encontró una distribución asimétrica de todas las variables estabilométricas analizadas en la población HAM/TSP diferente en el grupo no infectado (p <0,05). También fue posible verificar correlaciones de fuertes a moderadas e inversas entre las variables de oscilación del centro de gravedad con las puntuaciones obtenidas en la BBS, especialmente para AOT y OLL. Conclusión: Las personas con HAM/TSP presentaron valores más altos en las oscilaciones del centro de gravedad, las cuales se correlacionaron con la BBS en la evaluación del equilibrio.

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This article presents a description of the design, development, and implementation of web-based software and dedicated hardware which allows for the remote monitoring and control of a drip irrigation system. The hardware consists of in-field stations which are strategically distributed in the field and equipped with different sensors and communication devices; a weather station and drip irrigation system complete the setup. The web-based software makes it possible to remotely access and process the information gathered by all the stations and the irrigation controller. The proposed system was implemented in a young olive orchard, located in the province of San Juan, an arid region of Argentina. The system was installed and evaluated during the seasons 2014⁻2015 and 2015⁻2016. Four regulated irrigation strategies were proposed in the olive orchard to test its behavior. In this pilot experiment, the precision irrigation system was a useful tool for precisely managing the irrigation process, applying only the required amount of water (precise irrigation). Regulated deficit irrigation experiments, on the other hand, have demonstrated the sensitivity of olives to water restriction. The precision irrigation system made it possible to control soil moisture levels, avoiding water stress in the control treatment.

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Peripheral nerve stimulators have widespread among anaesthesiologists and remain a popular technique. However, in commercial devices, the user has to manually adjust stimulus intensity. Thus, the aim of this study is to propose a method that allows automating the current intensity control. An earlier nerve stimulator prototype was modified to add an accelerometer and an sEMG module. The choice of these two sensors is aimed at the possibility of observing the mechanical and electrical responses of the muscle contraction evoked by the stimulation. The tests were performed in two steps. The first step was to observe how the sensors behave during stimulation and muscle contraction. The second step was to implement a control algorithm and to validate the automation technique. Comparing the two methods, no significant differences were found on procedure time (manual: 12.5 ± 2.3; automatic: 11.6 ± 1.9; ρ =0.380) and blockade latency time (manual: 11.6 ± 1.1; automatic: 11.9 ± 1.2; ρ =0.524). Comparing needle-nerve distance in manual or automatic mode, no significant differences were found for 1.0 mA, 0.8 mA, 0.5 mA and 0.3 mA. We conclude that the technique for automating the current intensity update, using accelerometer and/or electromyography, is satisfactory. Furthermore, we conclude that the use of the accelerometer alone is sufficient for detection of muscle contraction.

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La agricultura en El Salvador es una actividad que se desarrolla aplicando técnicas tradicionales con poco grado de ingeniería y de automatización por parte de los agricultores. En el país existen pocas empresas dedicadas a la producción de verduras y hortalizas por medio de sistemas de invernaderos automatizados o con cierto de grado de control. Los costos de instalación de estos sistemas automatizados representan una alta inversión para la mayoría de agricultores que desean entrar en la industrialización de sus cultivos y aumentar la productividad y calidad de sus cosechas para lograr exportar sus frutos. Es por eso que la Escuela Especializada en Ingeniería ITCA-FEPADE, en conjunto con la Escuela Nacional de Agricultura ENA, se encuentra trabajando en el diseño y montaje de un prototipo de sistema automatizado para invernaderos familiares de menor costo, que les permita a los agricultores mejorar su condición económica por medio de una producción más controlada y protegida.

Agriculture in El Salvador is an activity that is developed by applying traditional techniques with little degree of engineering and automation by farmers. with a certain degree of control. The installation costs of these automated systems represent a high investment for the majority of farmers who wish to enter into the industrialization of their crops and increase the productivity and quality of their crops in order to export their fruits. That is why the ITCA-FEPADE Specialized School in Engineering, in conjunction with the National School of Agriculture ENA, is working on the design and assembly of a prototype of an automated system for lower-cost family greenhouses, which allow farmers improve their economic condition through a more controlled and protected production.

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Derivation of density-independent dielectric functions for moisture determination in grains is important for the implementation of on-line sensors in automated driers. The object of this study was to investigate the Meyer and Schilz function [(epsilon'1)/epsilon"] for indirect and non-destructive water content measurement of seeds of common bean by radiofrequency, where epsilon' and epsilon" are the relative permittivity and the dielectric loss factor, respectively. Samples consisted of common bean seeds variety Campeão-3 at moisture contents ranging from 11.5 to 20.6% w.b., and bulk densities from 756 to 854 kg m-3, performing dielectric measurements in a room at 20 ± 1ºC and 66 ± 2% relative humidity. The model could estimate common bean seed moisture content with a standard error of the estimate, and maximum error of 0.5 and 1.0 percentage point in moisture, w.b., respectively.

A obtenção de funções dielétricas que sejam independentes da massa específica aparente para estimar o teor de água dos grãos é importante para o desenvolvimento de sensores para utilização em secadores automáticos. O objetivo do presente trabalho foi avaliar a adequabilidade da função de Meyer e Schilz, [(épsilon'1)/épsilon"], para determinação indireta, não destrutiva e em linha do teor de água de sementes de feijão em radiofreqüências, em que épsilon' e épsilon" representam a permissividade elétrica relativa e o fator de perda dielétrica, respectivamente. Foram utilizadas amostras da variedade Campeão-3 com teor de água entre 11,5 e 20,6% b.u. e massa específica aparente no intervalo entre 756 e 854 kg m-3. Todas as medições das propriedades dielétricas foram feitas em ambiente a 20 ± 1ºC e umidade relativa de 66 ± 2%. O modelo permitiu estimar o teor de água das sementes de feijão com erro padrão da estimativa e erro máximo de 0,5 e 1,0 ponto percentual, respectivamente.

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Derivation of density-independent dielectric functions for moisture determination in grains is important for the implementation of on-line sensors in automated driers. The object of this study was to investigate the Meyer and Schilz function [(epsilon'1)/epsilon"] for indirect and non-destructive water content measurement of seeds of common bean by radiofrequency, where epsilon' and epsilon" are the relative permittivity and the dielectric loss factor, respectively. Samples consisted of common bean seeds variety Campeão-3 at moisture contents ranging from 11.5 to 20.6% w.b., and bulk densities from 756 to 854 kg m-3, performing dielectric measurements in a room at 20 ± 1ºC and 66 ± 2% relative humidity. The model could estimate common bean seed moisture content with a standard error of the estimate, and maximum error of 0.5 and 1.0 percentage point in moisture, w.b., respectively.

A obtenção de funções dielétricas que sejam independentes da massa específica aparente para estimar o teor de água dos grãos é importante para o desenvolvimento de sensores para utilização em secadores automáticos. O objetivo do presente trabalho foi avaliar a adequabilidade da função de Meyer e Schilz, [(épsilon'1)/épsilon"], para determinação indireta, não destrutiva e em linha do teor de água de sementes de feijão em radiofreqüências, em que épsilon' e épsilon" representam a permissividade elétrica relativa e o fator de perda dielétrica, respectivamente. Foram utilizadas amostras da variedade Campeão-3 com teor de água entre 11,5 e 20,6% b.u. e massa específica aparente no intervalo entre 756 e 854 kg m-3. Todas as medições das propriedades dielétricas foram feitas em ambiente a 20 ± 1ºC e umidade relativa de 66 ± 2%. O modelo permitiu estimar o teor de água das sementes de feijão com erro padrão da estimativa e erro máximo de 0,5 e 1,0 ponto percentual, respectivamente.