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Active power compensator for a DC voltage bus of a renewable source
No full textRenewable energy sources generate intermittent electrical power due to weather conditions, such as variations in wind speed and solar radiation. The nature of renewable energy sources requires new techniques to maintain the quality of electrical service and efficient use of energy. One of these techniques uses a battery bank when a renewable energy source does not generate the power level contracted by the utility grid. This article proposes a power compensator consisting of a bidirectional DC converter located between the battery bank and the DC bus of a renewable source. This compensator has two operation modes: one to store the excessive power in a battery bank; the other to deliver power when power intermittency occurs. The validation of the proposed power compensator is made using a prototype where the DC voltage bus of a renewable energy source is emulated through a DC generator-motor set, which allows bidirectional power flow
Indicadores financieros en el modelo de economía circular
No full textOrganizations need to produce products that are economically, socially,and environmentally balanced. The objective of the research was to validate the content of a Circular Economy (CE) measurement instrument for industrial organizations and contribute to sustainable development objectives. This was developed for a descriptive, non-experimental research. The content and relevance of the instrument was evaluated by six experts in the field. The result was a content validity ratio (CVR) of 1.00 as the highest and 0.20 as the lowest value, with an overall content validity index (CVI) of 0.75, which, according to the method used, the measurement instrument evaluated is admissibl
Seed morphometry and NaCl and sucrose effect on germination rates and phytochemicals in sotol (Dasylirion acrotrichum) from the Chihuahua state, Mexico
No full textIn Mexico, “sotoles” (Dasylirion spp.) are used to elaborate the “sotol”
liquor, handicraft making, and construction materials. These activities have
enhanced the probability that sotol populations could decline because plants are
extracted directly from their native ecosystems, given no commercial sotol plant
species exist. Furthermore, from an ecological point of view, this genus has also
been little studied regarding its seed morphology and germination process. The
objective of this study was to characterize the morphometry of the D. acrotrichum
seeds and to evaluate the effect of different concentrations of NaCl (30, 60, and 90
mM) and sucrose (30, 60, and 90 mM) on seed germination rates, seedling
morphology, and the phytochemical content in the seedling leaves under in vitro
conditions from plants grown in the Chihuahua State. The exogenous NaCl and
sucrose treatments influenced the germination speed index, mean germination
time, and mean germination speed. The NaCl treatment impacted the total weight,
root weight, and leaf length of seedlings, the content of chlorophyll a, sugar, and
phenolics, and the antioxidant activity determined by FRAP. Besides, the sucrose
treatment affected the seedling length, the content of chlorophyll a, chlorophyll b,
total chlorophyll, and sugars, and the antioxidant activity determined by FRAP and
DPPH. These results could provide the guidelines to generate better afforestation
programs in the areas affected by the overexploitation of the Dasylirion spp. and
new information about the capacity of these species for developing under these
types of stress in the natural environment
Effect of ionizing radiation on the microstructure and physical properties of endodontic gutta-percha points
No full textPurpose
Patients undergoing radiotherapy for head or neck cancer often require root canal
treatments, which can be compromised by the effects of radiation. This investigation
aimed to determine whether ionizing radiation (IR), in doses similar to those used
in conventional therapy, affects the surface and physicomechanical properties of
various brands of endodontic gutta-percha points (EGPs).
Materials and Methods
One hundred and twenty-three EGPs from three brands (Meta-Biomed, Dentsply,
and Hygenic) were divided into groups and either exposed or not exposed to IR at
a total dose of 50 Gy, divided into 25 fractions. Tensile strength and microhardness
tests were performed on all EGPs. Scanning electron microscopy was utilized
to identify possible microstructural surface changes due to IR exposure. The
proportion of organic to inorganic components in each brand was also determined.
Results
Exposure to IR resulted in significant changes only in the EGPs from the Meta Biomed brand, including a notable decrease in tensile strength and an increase in
microhardness. Furthermore, the surface microstructure of these EGPs displayed
dark lines and striations over a large area, with some lines deeply embedded in the
center and cavities of variable depths and extensions observed, leading to irregular
and non-smooth surfaces. This brand had the highest proportion of organic
components.
Conclusion
The physicomechanical properties and surface microstructure of Meta-Biomed
brand EGPs were significantly affected by IR at doses used in conventional therapy
for head or neck cancer, while the other brands were less affected or unaffected
Determination of sensory, microbiological and antioxidant properties of tortilla added with Roselle decoction calyxes powder
No full textThe aim was to assess the sensory, microbiological, physical, and antioxidant properties of corn and wheat tortillas formulated with varying HDC concentrations. Sensory evaluation revealed that the corn and wheat tortillas with 20% HDC achieved the highest overall acceptability in terms of mouthfeel, color, and flavor attributes. The addition of HDC significantly reduced microbial growth compared to the control tortillas. All formulations displayed significant variations in quality properties. Tortillas containing HDC demonstrated significantly higher levels of TSPCC, TFC, and antioxidant capacity
Application of web managers for document classification in an academic office
No full textWeb managers, as technological tools, play a crucial role in the optimization of administrative processes by offering efficient solutions for the management of information and documents. Their impact in the administrative area lies in the simplification of tedious tasks and the improvement of the organization and accessibility of data. The implementation of a web manager aims to automate classification and search processes; web managers allow organizations to save time and resources, while increasing productivity and accuracy in decision making. The Scrum methodology was applied to the development of a web manager application for a Higher Education Department (DES) in Mexico, due to its adaptability and flexibility, facilitating continuous delivery and constant improvement through short iterations. As a result, a web manager with a real-time search engine was developed which meets the criteria of the ISO/IEC 9126 standard. However, limitations include the need to host the project on a server for broader access. The conclusions derived from the study are that the implementation of a web manager with a real-time search engine offers a novel solution to automate the classification of files in an educational institution
Implementation of a method for inventory control in a family microenterprise
No full textSmall and medium-sized enterprises (SMEs) form the basis of the national and international economy. However, they are constantly faced with a wide variety of challenges that they are often unable to overcome. For this reason, this article emphasizes the importance of having at least one inventory control that allows you to know the situation in real time and establish strategies to increase profitability. The objective of this work is the implementation of an inventory control method in a family microenterprise in Ciudad Jiménez, Chihuahua, Mexico. The methodology consists of three stages: creating a database, performing a descriptive analysis of sales, and implementing the maximum and minimum method. Among the results, a high dispersion in sales behavior is reported, as well as an excess of inventory in three of the five selected products. In conclusion, this study highlights the importance of having inventory control that allows us knowing the behavior of sales, as well as avoiding shortages or surpluses that directly impact the profitability of the company
Noise Pollution and Ergonomic Intervention by Acoustic Material
No full texthttps://link.springer.com/book/10.1007/978-3-031-66308-
El mito de la caída de Lucifer y su representación en los villanos de las películas animadas de Walt Disney
No full textSe analiza a los antagonistas de la industria de Walt Disney Animation
Studios mediante una visión hermenéutica sobre el mito de la caída de Lucifer. Se
retoma cómo dicha figura es representada en los personajes de las animaciones desde
su diseño y narrativa. Por ello, se estudia el mito desde sus orígenes, además de inda-
gar en el recorrido histórico de la compañía de animación para comprender los cam-
bios realizados en los personajes según su contexto. Una vez revisados los temas se
presenta una propuesta de análisis dividida en siete etapas, donde Lucifer: 1) existe
primero como figura de autoridad, 2) aparece un detonante, 3) se da una transmuta-
ción (física o espiritual), 4) llega la caída social, 5) le sigue la caída física, 6) es con-
denado al exilio y 7) muere. Tal modelo se aplica a los proyectos fílmicos de 1937 a
2016. Los resultados señalan las singularidades en el desarrollo de los personajes ani-
mados y su relación mimética con Lucifer, así como su caída fina
The impact of catholic titles on the perception and aestheticisation of violence in figurative painting
No full textThe impact of Catholic Titles on figurative paintings depicting violence were studied using both explicit and implicit measures. When paintings were described as Catholic, they were significantly rated as more beautiful and interesting, and less violent than when they were described as Non-Catholic. Therefore, demonstrating that Catholic themes associated with these artworks overshadow their violent content. This was demonstrated via hedonic ratings. Thus, suggesting an aestheticisation of violent imagery when connected to Catholic themes. Implicit responses, assessed using the Implicit Association Test, showed faster responses when Violent Catholic Paintings were associated Positive Adjectives and slower responses were associated when violent Non-Catholic Paintings were associated with Negative Adjectives. These implicit responses confirm previous explicit results