Sliding Mode Control of a Nonlinear Wave Energy Converter Model

The most accurate wave energy converter models for heaving point absorbers include nonlinearities, which increase as resonance is achieved to maximize energy capture. The efficiency of wave energy converters can be enhanced by employing a control scheme that accounts for these nonlinearities. This project proposes a sliding mode control for a heaving point absorber that includes the nonlinear effects of the Froude-Krylov force. The sliding mode controller tracks a reference velocity that matches the phase of the excitation force to ensure higher energy absorption. This control algorithm is tested in regular linear waves and is compared to a complex-conjugate control and a nonlinear variation of the complex-conjugate control. The results show that the sliding mode control successfully tracks the reference, keeps the device displacement bounded, and absorbs more energy than the other control strategies. Furthermore, the controller can accommodate disturbances and uncertainties in the dynamic model

READING HABITS OF STUDENTS OF THE NATIONAL UNIVERSITY OF EDUCATION, ECUADOR, AND ITS EFFECTS ON THEIR PERFORMANCE IN READING IN THE TARGET LANGUAGE

The study aims to assess the impact of students' reading habits in their first language (L1) on their English acquisition at the National University of Education. It found that students who do not frequently read in their first language negatively influence their second language reading habits, resulting in a lack of vocabulary acquisition and fundamental grammatical structure management. As English professors, we were concerned about the underperformance in reading abilities of our students. This was further evidenced by the poor scores of learners who took the B1 test, particularly in the reading section. As a result, we began investigating the reading habits of students and the possible factors that contribute to their low reading proficiency. In the study, we administered a survey and a diagnostic test to 70 students from level five and 29 students from level six. The results showed that an extensive number of students read scarcely. A considerable number of students did not read at all. Only a minority of the assessed students read routinely. We compared the results from the survey with the data collected by the diagnostic test. We observed that students who barely read in L1 did not reach a high-performance score in their diagnostic. Furthermore, we concluded that reading in their mother tongue influences their reading performance in the target language. Therefore, it is necessary to motivate students to enhance their reading skills in the first and second language to acquire the vocabulary and grammar knowledge needed to improve their level of English.  Article visualizations

Evaluación Comparativa del Desarrollo Integral de las Familias Beneficiarias con el Programa Productivo Alimentario y las Familias no Beneficiarias desde las comunidades de: Quebrada Honda, La pita, Lizarco, Guayacán, Chilamate y El Palacio, San Nicolás; del núcleo, “Mujeres progresiva en la cadena alimenticia”

La presente investigación se realizó con el fin de evaluar comparativamente el desarrollo integral de las familias campesinas rurales pobres del municipio de Matagalpa beneficiarias y no beneficiarias del Programa Productivo Alimentario y así valorar el cumplimiento de los objetivos del bono, la comparación se hizo con familias de iguales características de las comunidades; Quebrada Honda, La pita, Guayacán, Chilamate, Lizarco, El Palacio y San Nicolás , correspondiente al núcleo Mujeres Progresivas en la Cadena Alimentaria. Para realizar dicha evaluación comparativa se realizó la construcción de una escala en base a la teoría e Likert definiendo los objetivos y las variables que pretendimos medir siendo las principales, desarrollo a Escala Humana, desarrollo Comunitario, desarrollo socioeconómico. El PPA contribuye a un nuevo modelo de desarrollo sin embargo actualmente su ejecución es ineficiente y esto provoca que los resultados esperado sean mínimos con relación a los objetivos planteados lo cual no permite que este se convierta en un nuevo modelo de desarrollo para las familias en un corto plaz

Fragilidade nas redes internacionais de cooperação empresarial

O objetivo do artigo é discutir a fragilidade nas redes internacionais de cooperação empresarial. A metodologia baseou-se no realismo crítico, aplicou-se num questionário, em entrevistas, numa sondagem, em visitas de campo e na observação sistemática, recuperou-se evidência sobre a criação, rutura e prolongamento dos vínculos. O método de investigação foi qualitativo e a análise pela triangulação por especialistas. Os resultados (171 empresas estudadas durante um período de 9 anos) mostram que 81% mantém vínculos internacionais, apesar de que 61% esteve sujeito a atos de oportunismo e ao fracasso; no entanto, 91% procura novos vínculos. A principal conclusão é que a competência não debilita necessariamente a rede; em muitas ocasiões fortalece-a: um ato de oportunismo abre a possibilidade de que os agentes cooperem e uma experiência de fracasso facilita a criação de novos vínculos

Aplicación de la sección N°13: Inventarios de las NIIF para PYMES en la pequeña empresa “Farmacia Oziris N°2” del municipio de Matagalpa en el I semestre del año 2012

Esta investigación trata sobre la “Capacidad de adopción de las NIIF para PYMES en la pequeña empresa “Farmacia Oziris N°.2” del municipio de Matagalpa en el I semestre del año 2012.” Las NIIF para PYMES son un conjunto de normas contables que se basan en las NIIF completas, para satisfacer las necesidades y capacidades que tienen de las pequeñas y medianas empresas (PYMES). Estas se han convertido en el motor principal del sector económico de cada país. Toda empresa que se dedica a realizar una actividad comercial tiene que llevar contabilidad apegado a una normativa contable que rija sus ingresos y egresos que esta perciba. Es por esto la importancia de estudiar e investigar las NIIF para PYMES sobre los requerimientos, presentación, medición e información a revelar en los estados financieros de la empresa. La Farmacia Oziris N°.2 no aplica ninguna normativa contable por el momento, pero sería relevante que fuese una de las primeras empresas en la ciudad de Matagalpa en adoptar este conjunto de normas, para presentación, elaboración de sus Estados Financieros. Las NIIF para PYMES son normas contables para uso y aplicación para pequeñas y medianas empresas, Farmacia Oziris N°.2 posee capacidades físicas, económicas y personal para aplicar la sección N°13: inventario

“I’m Going to Live My Life Freely”: Authenticity as an Indicator of Belonging Among Urban Latinx LGBTQ+ Youth

While there is a growing body of scholarship on the experiences of LGBTQ+ youth in school and community settings, less is known about Latinx LGBTQ+ youth specifically. In response, this phenomenological study examined the experiences of eight Latinx LGBTQ+ youth relative to school and community belonging, with a specific focus on urban environments, using intersectionality and minority stress frameworks, and Lee and Robbins’ operational definition of belongingness. Three overarching themes emerged from the data: (a) navigating challenges, (b) the importance of an inclusive climate, and (c) thriving through adversity. Further, authenticity was identified as an additional indicator of belonging among Latinx LGBTQ+ youth. This article reviews the study’s findings, explores implications for Extension research and practice, and suggests strategies for educators and youth-serving professionals

Sliding mode control of a nonlinear wave energy converter model

The most accurate wave energy converter models for heaving point absorbers include nonlinearities, which increase as resonance is achieved to maximize the energy capture. Over the power production spectrum and within the physical limits of the devices, the efficiency of wave energy converters can be enhanced by employing a control scheme that accounts for these nonlinearities. This paper proposes a sliding mode control for a heaving point absorber that includes the nonlinear effects of the dynamic and static Froude‐Krylov forces. The sliding mode controller tracks a reference velocity that matches the phase of the excitation force to ensure higher energy absorption. This control algorithm is tested in regular linear waves and is compared to a complex‐conjugate control and a nonlinear variation of the complex‐conjugate control. The results show that the sliding mode control successfully tracks the reference and keeps the device displacement bounded while absorbing more energy than the other control strategies. Furthermore, due to the robustness of the control law, it can also accommodate disturbances and uncertainties in the dynamic model of the wave energy converter

Nosocomial infection: Nursing care to reduce bacteremia associated with venous catheters in an intensive care unit

Definimos la infección nosocomial como la que aparece al ingreso del paciente, que se manifiesta a las 72 h o más del ingreso y que en el momento del ingreso no estaba. Es la complicación más común en pacientes hospitalizados. La cuarta parte de estas infecciones ocurren en Unidades de Cuidados Intensivos. En particular las infecciones intrahospitalaria por el uso de catéteres venosos son la causa mas frecuente de bacteriemia nosocomial. Por todo ello las medidas preventivas son esenciales para disminuir la incidencia de infecciones asociadas a catéteres, donde los cuidados de enfermería juegan un papel muy importante.We defined the nosocomial infection as the one that appears at the patient's admission, which manifests at 72 h or more of the admission and that was not present at the time of admission. It is the most common complication in hospitalized patients. A quarter of these infections occur in Intensive Care Units. In particular, intrahospital infections due to the use of venous catheters are the most frequent cause of nosocomial bacteremia. Therefore, preventive measures are essential to reduce the incidence of infections associated with catheters, where nursing care plays a very important role

pressure ulcers in the intensive care unit

La presión ejercida de forma constante sobre regiones corporales se presenta como el primer y fundamental agente causal en la producción de UPP, esto provoca un empeoramiento en el nivel de salud haciendo que se aumenten los días de estancia hospitalaria, riesgo de complicaciones o de los costes de tratamiento, entre otros. Por eso es importante conocer e identificar las UPP, realizar una buena prevención y saber como tratar las UPP desde el momento de su aparición evitando las posibles complicaciónes.The constant pressure exerted on body regions is presented as the first and fundamental causative agent in the production of UPP, this causes a worsening in the level of health by increasing the days of hospital stay, risk of complications or costs of treatment, among others. That is why it is important to know and identify the UPP, make a good prevention and know how to treat the UPP from the moment of its appearance avoiding possible complications

Slow-wave activity in the S1HL cortex is contributed by different layer-specific field potential sources during development

Spontaneous correlated activity in cortical columns is criticalfor postnatal circuit refinement.We used spatial discriminationtechniques to explore the late maturation of synaptic pathways through the laminar distribution of the field potential (FP) generators underlying spontaneous and evoked activities ofthe S1HL cortex in juvenile (P14 –P16) and adult anesthetized rats. Juveniles exhibit an intermittent FP pattern resembling Up/Down states in adults, but with much reduced power and different laminar distribution. Whereas FPs in active periods are dominated by a layer VI generator in juveniles, in adults a developing multipart generatortakes over, displaying current sinks in middle layers (III–V). The blockade of excitatory transmission in upper and middle layers of adults recovered the juvenile-like FP profiles. In additiontothe layer VI generator, a gamma-specific generator in supragranular layers wasthe same in both age groups.While searching for dynamical coupling among generators in juveniles we found significant cross-correlation in one-half of the tested pairs, whereas excessive coherence hindered their efficient separation in adults. Also, potentials evoked by tactile and electrical stimuli showed different short-latency dipoles between the two age groups, and the juveniles lacked the characteristic long latency UP state currents in middle layers. In addition, the mean firing rate of neurons was lower in juveniles. Thus, cortical FPs originate from different intracolumnar segments as they become active postnatally. We suggest that although some cortical segments are active early postnatally, a functional sensory-motor control relies on a delayed maturation and network integration of synaptic connections in middle layers