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Model Predictive Control in Multilevel Inverters Part II : Renewable Energies and Grid Applications
No full textPublisher Copyright: © 2020 IEEE.This article presents the use of model predictive control (MPC) in multilevel inverters for some applications, such as, first, wind generation and, second, photovoltaics, showing that the particular restrictions of each of them can be very easily included in the control algorithm, which is an important advantage of this technique. Another application is in modular multilevel cascaded converters, where it is demonstrated that MPC can operate with very few calculations and fixed switching frequency. The second part of this article is dedicated to comparing MPC with linear control and pulsewidth modulation for multilevel inverters. The main comparison criteria are the switching losses, the distortion in the load current, and the number of commutations. The main conclusion is that MPC is a competitive alternative to linear control for application in multilevel inverters
Weak Value Amplification of Photons in Optical Nonlinear Medium, Opto-Mechanical, and Spin-Mechanical Systems
No full textPublisher Copyright: © 2024 by the authors.A measurement of an observable A performed on a quantum system that is initially prepared in a state (Formula presented.), followed by a probabilistic procedure that leaves the system in a final state (Formula presented.), a process often referred as state postselection (or filtering process), can yield, on average, anomalous measurement results, i.e., values that may exceed the eigenvalue range of the observable being measured or be complex numbers. There is, therefore, an amplification effect of the average measurement result, i.e., the effect of the system on the measurement device is increased. When the coupling between the system and the measurement device satisfies some weakness conditions, the amplification effect occurs due to the weak value of the operator A. In this article, the amplification effect due to the postselection process is reviewed, and theoretical proposals and experiments published in the recent literature on the field are commented on. The emphasis is made on interactions occurring in optical nonlinear media and opto-mechanical and spin-mechanical systems, in which the amplification of number operators takes place
La harina de semillas de albahaca con alto contenido de fibra reduce la resistencia a la insulina y la esteatosis hepática en ratones dietéticos ricos en grasas
No full textPublisher Copyright: © The Author(s) 2024.The incidence of insulin resistance (IR) and hepatic steatosis is increasing, with dietary fiber playing a protective role against these disorders. Ocimum basilicum L., widely used in food, pharmaceutical, and cosmetic industries, but their health-promoting properties remain underexplored. This study evaluated the effects of a fiber-rich fraction of partially defatted basil seeds (BSF) on IR, hepatic steatosis, and polyunsaturated fatty acid and short-chain fatty acid (SCFA) profiles in high-fat diet (HFD)-fed C57BL/6 J male mice. Mice were assigned to four groups and fed either a control diet or HFD, supplemented with BSF or oat flour for 4 weeks. HFD induced IR, hepatic steatosis, proinflammatory state, and a significant decreased in SCFA production. In contrast, supplementation with BSF attenuated IR, steatosis, liver damage, oxidative stress, and inflammation, while increasing n-3 polyunsaturated fatty acids in liver, adipocytes, and erythrocytes, and enhancing SCFA production, suggesting potential therapeutic benefits in managing these conditions
Revisión bibliográfica sobre la rotura de ligamento cruzado craneal en caninos (canis lupus familiaris) enfocada en tratamientos y diagnósticos entre los años 2019-2024
Get PDFLa rotura del ligamento cruzado craneal (LCC) es una lesión frecuente en perros que requiere un diagnóstico preciso para guiar el tratamiento adecuado. Inicialmente, se utiliza el examen clínico con pruebas como la prueba de cajón y la de compresión tibial, complementadas con pruebas imagenológicas como radiografías y ecografías, y ocasionalmente artroscopía para confirmar el diagnóstico. En términos de tratamiento, se distinguen dos enfoques principales: conservador y quirúrgico. El tratamiento conservador implica reposo, medicación analgésica y antiinflamatoria, junto con fisioterapia para mantener la función articular y prevenir la osteoartritis. Por otro lado, el tratamiento quirúrgico ofrece opciones más definitivas, como técnicas intracapsulares, extracapsulares y osteotomías, cada una con sus propias consideraciones según el tamaño y las características del perro. Es crucial considerar que tanto el tratamiento conservador como el quirúrgico conllevan riesgos y pueden requerir un manejo postoperatorio cuidadoso para optimizar la recuperación y minimizar complicaciones adicionales. La elección del tratamiento apropiado debe basarse en la evaluación individualizada de cada caso, considerando factores como la edad del animal, su nivel de actividad y la gravedad de la lesión.Cruciate ligament rupture (CLR) is a common injury in dogs that requires precise diagnosis to guide appropriate treatment. Initially, clinical examination is used with tests such as the drawer test and tibial compression test, complemented by imaging tests such as radiography and ultrasound, and occasionally arthroscopy to confirm the diagnosis. In terms of treatment, two main approaches are distinguished: conservative and surgical. Conservative treatment involves rest, analgesic and anti-inflammatory medication, along with physiotherapy to maintain joint function and prevent osteoarthritis. On the other hand, surgical treatment offers more definitive options, such as intracapsular, extracapsular, and osteotomy techniques, each with its own considerations based on the size and characteristics of the dog. It is crucial to consider that both conservative and surgical treatments carry risks and may require careful postoperative management to optimize recovery and minimize additional complications. The choice of appropriate treatment should be based on individual evaluation of each case, considering factors such as the age of the animal, its activity level, and the severity of the injury
ESG performance on the value of family firms: international evidence during Covid-19
No full textThe link between the financial success of family companies during COVID-19 and their environmental, social, and governance (ESG) performance is examined for the first time in this research. We have a natural setting in the COVID-19 era to see if the market rewards family-run firms that integrate social and environmental concerns into their goals during uncertain times. Since they can enhance their image and reputation, which the market values, these companies are likely to pursue broader social objectives, such as environmental improvement (socioemotional wealth perspective); alternatively, managers can act as stewards of the family’s interests by using these initiatives to increase the company’s value (stewardship perspective). However, it is also possible that in this type of companies economic interests prevail over social wellness (“amoral familism”). Therefore, family-owned firms could be reluctant to implement ESG practices unless they yield certain socioemotional benefits, including enhancing or maintaining their reputation in the public eye. In light of the above, we use an international display of the 500 biggest family firms in the world from 2015 to 2021. Taking into account an endogenous relationship between ESG performance and family business value, the study uses generalized moments to construct a dynamic panel (GMM). The primary conclusion is that there is a positive correlation between corporate valuation and ESG performance. Nonetheless, it has been noted that the performance of the companies is negatively impacted during the COVID-19 period. However, for firms with superior ESG performance, this negative impact did not exist over this period, supporting the idea that investors view better ESG performance as a prediction of future good stock performance. The results have a variety of implications. To begin with, this study adds to the body of knowledge on the environmentally friendly and sustainable expansion of family companies by providing recommendations for investors and businesses to better understand the influence of ESG on the profitability of family businesses. Furthermore, managers have to concentrate on enhancing the ESG performance of their organizations as it has the potential to increase value, draw in investments, encourage sustainability, control risks, affect earnings, and interact with the ownership structure. Additionally, managers need to consider how important it is to have a strong ESG performance in order to mitigate the negative effects of external crises like the COVID-19 epidemic. It’s crucial to remember that the precise impact might change based on the sector and other aspects unique to each company
Artificial Bee Colony Algorithm to Optimize the Safety Distance of Workers in Construction Projects
No full textPublisher Copyright: © 2024 by the authors.This paper presents the results of a simulation model regarding the productivity and safety working space for construction workers through the floors of a building using swarm intelligence (SI), a field of artificial intelligence (AI), and specifically using artificial bee colony (ABC) optimization. After designing the algorithm used to build the simulation model, the simulation was used in an actual building project by comparing the travel times of workers conventionally transporting material with another group working on routes optimized by the algorithm. Thus, the proposed algorithm provides routes combining shorter travel times and correct distances between workers when transporting materials in a construction site, handling the interference between crews. After validating the algorithm on-site, no statistically significant differences were found between the travel times of workers and the times delivered by the algorithm. Additionally, the travel times using the routes obtained through the algorithm were significantly lower than those made by workers who moved freely without a predefined route. In summary, the algorithm proposed may help construction practitioners maintain safe movements that respond to hazard contexts imposed by any restriction that demands a safety distance
Focus on the future of water-limited agricultural landscapes
No full textPublisher Copyright: © 2024 The Author(s). Published by IOP Publishing LtdWater scarcity and related climate volatility are growing constraints on agricultural production landscapes around the world. While the adaptation options available are often dictated by system context, in many places broad-scale transformations are occurring in response to water-related pressures. We sought contributions from across regions, agricultural system types, and scientific disciplines to examine agricultural land use transitions driven by water scarcity, including the tradeoffs associated with alternative land uses; impacts on food production, environment, and society; innovations that can buffer risk; and considerations for planning and implementation. The research presented in this collection highlights the spectrum of policy and practice changes that are needed to facilitate beneficial land use transitions and system transformations, from quantifying risks, to evaluating multidimensional tradeoffs, to developing socio-technical policy bundles to maximize co-benefits
Análisis de prefactibilidad técnica y económica de la formulación y comercialización de una bebida energética saludable
No full textSegún un estudio realizado en el año 2022 por la Corporación Nacional de
Consumidores y Usuarios (CONADECUS) estableció que existe un aumento en el
consumo de bebidas energéticas en el país y que su consumo promedio per cápita
mensual de estos productos es de 3,6 litros al mes y que las personas que mayor
consumo poseen son las comprendidas entre las edades de 14 y 34 años, tomando
datos entre el año 2010 y 2020.
A partir de estos datos, se ha establecerá una manera de satisfacer la demanda a
través de un producto que como ingrediente principal sea la Maltodextrina,
carbohidrato de cadena corta con una rápida absorción en el organismo que
abastecerá de energía en los períodos de entrenamiento, deporte o ejercicios
cotidianos, con adición de macronutrientes como vitaminas y minerales que apoyen
con el desgaste físico y mental que conlleva.
De esta forma, se encuentra una oportunidad para producir y distribuir una bebida
energética que disminuya los impactos a la salud propensas por su alto consumo
sin mermar la intencionalidad de su consumo que es el aumento de energía.
Como objetivo, se realizará un estudio económico y financiero para evaluar la
viabilidad comercial, tecnológica, económica y financiera para la producción y
distribución en el mercado de las bebidas energéticas, teniendo en consideración
los factores internos y externos, la aplicación de herramientas ingenieriles y la
estimación de una demanda la cual se trabajará y establecerá una gestión de
procesos para que este proyecto tenga como meta el éxito esperado. (Durán, 2022)According to a study conducted in 2022 by the National Consumer and User
Corporation (CONADECUS), there has been an increase in the consumption of
energy drinks in the country, with an average per capita consumption of 3.6 liters per
month. The highest consumption is among people aged 14 to 34, based on data
collected between 2010 and 2020.
Based on this data, a way will be established to meet the demand through a product
with maltodextrin as the main ingredient. Maltodextrin is a short-chain carbohydrate
with rapid absorption in the body, which will provide energy during periods of training,
sports, or daily exercise. The product will also contain macronutrients such as
vitamins and minerals to support the physical and mental fatigue that comes with
these activities.
In this way, there is an opportunity to produce and distribute an energy drink that
reduces the health risks associated with high consumption without compromising its
primary purpose of increasing energy.
As an objective, an economic and financial study will be conducted to evaluate the
commercial, technological, economic, and financial viability of producing and
distributing energy drinks in the market, considering internal and external factors, the
application of engineering tools, and the estimation of demand. A process
management plan will also be established to ensure the project achieves the
expected success
Actividades y textos literarios sugeridos para la enseñanza de la Literatura en el espacio escolar en Chile: ¿estereotipos de género y su reproducción en la escuela?
No full textLa evidencia nos indica que la Literatura y su discusión en la escuela permiten renovar las relaciones sociales y promover espacios de aceptación desde la hospitalidad (Cassany, 2005; Colomer, 2015); de ahí la relevancia de reflexionar sobre los estereotipos de género que se reconstruyen en la escuela y así contribuir al fortalecimiento de espacios educativos inclusivos basados en la equidad de género. Este estudio analiza y propone algunas ideas sobre el tratamiento de estereotipos de género presentes en los programas de estudio de Lengua y Literatura del Ministerio de Educación chileno, a través de la revisión de textos literarios propuestos y de las características de las actividades sugeridas. Los resultados indican que, pese a que sí se evidencia una incorporación de perspectiva de género en la documentación, los análisis propuestos giran principalmente en torno a la figura de la mujer, la cual se reconstruye ligada a estereotipos cuyo estudio y discusión en el aula, dependiendo del énfasis otorgado por cada docente, intentaría con cierta dificultad resolver los dilemas de género propios de nuestra sociedad
Multi-Species Biofilm Interactions and Their Impact on the Biocorrosion of Copper-Coated CoCr Alloys in Dental Application
No full textPublisher Copyright: © 2024 by the authors.Biocorrosion of materials used in dental restorations is a complex process involving various bacterial species that coexist as biofilms. Since copper possesses excellent antibacterial properties, it could help minimize this problem. The aim of this study is to assess the antibiofilm characteristics and corrosion resistance of CoCr and copper-coated CoCr alloys in a multispecies biofilm model. CoCr alloys and CoCr coated with copper (CoCr/Cu) using Physical Vapor Deposition (PVD) were investigated. The samples were incubated in media with and without a multispecies biofilm for 24 h and for 15 days. Potentiodynamic Polarization and Electrochemical Impedance Spectroscopy (EIS) were used to assess the corrosion behavior of the samples. Scanning Electron Microscopy (SEM) was utilized to observe the growth of multispecies biofilms and the type of corrosion. The Mann–Whitney U test was employed to examine corrosion results, with significant differences defined as p < 0.05. CoCr/Cu alloys demonstrated superior corrosion resistance at 24 h and 15 days in the presence of biofilm compared to those without coating. No differences were observed in multispecies biofilm formation at 24 h. The study demonstrates that copper-coated CoCr alloys (CoCr/Cu) exhibit a more positive corrosion potential (Ecorr) compared to uncoated CoCr alloys, both in the presence and absence of multispecies biofilm (BP) at 24 h and 15 days. After 15 days, the potential of CoCr/Cu with BP was −0.144 V, compared to −0.252 V for uncoated CoCr. These significant differences in Ecorr values underscore the protective effect of copper against corrosion in multispecies biofilm environments