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Impact of automation on enhancing energy quality in grid-connected photovoltaic systems

Virgilio Alfonso Murillo Rodríguez NOE VILLA VILLASEÑOR José Manuel Robles Solís OA Guirette-Barbosa (2023, [Artículo])

Rapid growth in the integration of new consumers into the electricity sector, particularly in the industrial sector, has necessitated better control of the electricity supply and of the users’ op-erating conditions to guarantee an adequate quality of service as well as the unregulated dis-turbances that have been generated in the electrical network that can cause significant failures, breakdowns and interruptions, causing considerable expenses and economic losses. This research examines the characteristics of electrical variations in equipment within a company in the industrial sector, analyzes the impact generated within the electrical system according to the need for operation in manufacturing systems, and proposes a new solution through automation of the regulation elements to maintain an optimal system quality and prevent damage and equipment failures while offering a cost-effective model. The proposed solution is evaluated through a reliable simulation in ETAP (Energy Systems Modeling, Analysis and Optimization) software, which emulates the interaction of control elements and simulates the design of electric flow equipment operation. The results demonstrate an improvement in system performance in the presence of disturbances when two automation schemes are applied as well as the exclusive operation of the capacitor bank, which improves the total system current fluctuations and improves the power factor from 85.83% to 93.42%. Such a scheme also improves the waveform in the main power system; another improvement result is when simultaneously operating the voltage and current filter together with the PV system, further improving the current fluctuations, improving the power factor from 85.83% to 94.81%, achieving better stability and improving the quality of the waveform in the main power grid.

This article belongs to Special Issue Advances and Optimization of Electric Energy System.

Power quality Capacitor bank Voltage and current filter Photovoltaic system INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS

Influence of conservation agriculture-based production systems on bacterial diversity and soil quality in rice-wheat-greengram cropping system in eastern Indo-Gangetic Plains of India

Anup Das virender kumar Peter Craufurd Andrew Mcdonald Sonam Sherpa (2023, [Artículo])

Introduction: Conservation agriculture (CA) is gaining attention in the South Asia as an environmentally benign and sustainable food production system. The knowledge of the soil bacterial community composition along with other soil properties is essential for evaluating the CA-based management practices for achieving the soil environment sustainability and climate resilience in the rice-wheat-greengram system. The long-term effects of CA-based tillage-cum-crop establishment (TCE) methods on earthworm population, soil parameters as well as microbial diversity have not been well studied. Methods: Seven treatments (or scenarios) were laid down with the various tillage (wet, dry, or zero-tillage), establishment method (direct-or drill-seeding or transplantation) and residue management practices (mixed with the soil or kept on the soil surface). The soil samples were collected after 7 years of experimentation and analyzed for the soil quality and bacterial diversity to examine the effect of tillage-cum-crop establishment methods. Results and Discussion: Earthworm population (3.6 times), soil organic carbon (11.94%), macro (NPK) (14.50–23.57%) and micronutrients (Mn, and Cu) (13.25 and 29.57%) contents were appreciably higher under CA-based TCE methods than tillage-intensive farming practices. Significantly higher number of OTUs (1,192 ± 50) and Chao1 (1415.65 ± 14.34) values were observed in partial CA-based production system (p ≤ 0.05). Forty-two (42) bacterial phyla were identified across the scenarios, and Proteobacteria, Actinobacteria, and Firmicutes were the most dominant in all the scenarios. The CA-based scenarios harbor a high abundance of Proteobacteria (2–13%), whereas the conventional tillage-based scenarios were dominated by the bacterial phyla Acidobacteria and Chloroflexi and found statistically differed among the scenarios (p ≤ 0.05). Composition of the major phyla, i.e., Proteobacteria, Actinobacteria, and Firmicutes were associated differently with either CA or farmers-based tillage management practices. Overall, the present study indicates the importance of CA-based tillage-cum-crop establishment methods in shaping the bacterial diversity, earthworms population, soil organic carbon, and plant nutrient availability, which are crucial for sustainable agricultural production and resilience in agro-ecosystem.

Metagenomics Bacterial Diversity Rice-Wheat-Greengram CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CONSERVATION AGRICULTURE DNA SEQUENCES EARTHWORMS METAGENOMICS SOIL QUALITY AGROECOSYSTEMS

Seed integrity, effect of temperature and storage time on germination of Populus luziarum and P. primaveralepensis, endangered subtropical species from Mexico

César Jacobo Pereira MIGUEL ANGEL MUÑIZ CASTRO JOSE ANTONIO VAZQUEZ GARCIA Joel David Flores Rivas ALEJANDRO MUÑOZ URIAS FRANCISCO MARTIN HUERTA MARTINEZ (2022, [Artículo])

"Background: Populus luziarum and P. primaveralepensis are endemic species of western Mexico; growing in riparian forests they are critically endangered. The best way to conserve their seeds is unknown, which could be limiting for their conservation.

Hypothesis: The germinability of both subtropical species is like that of boreal and template Salicaceae species that disperse seeds in spring and early summer, as they germinate quickly with high percentages, and rapidly lose their viability when stored at ambient temperature.

Studied species: Populus luziarum and P. primaveralepensis. Study site and dates: Western Trans-Mexican Volcanic Belt. Jalisco, Mexico. October 2019.

Methods: The physical integrity of the seeds was assessed by X-ray imaging and compared with germinability. In addition, the effect of storage time (nine weeks) under two temperatures (4 and 21 °C) on the percentage and mean germination rate was evaluated.

Results: No significant differences were found between physical integrity and germination in freshly collected seeds for both species. Germination in the first 24 hrs was 91 and 95 % for Populus luziarum and P. primaveralepensis, respectively (week 0). Germination percentages were lower when stored at 21 °C, but P. primaveralepensis was decreased more slowly.

Conclusions: Seeds of subtropical Populus respond similarly to those of species from temperate and boreal climates with early seed dispersal, a crucial condition for establishing ex situ reforestation and conservation programs."

Salicaceae Seed physical integrity Seed storage conditions Subtropical endemic species White poplars BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) BIOLOGÍA VEGETAL (BOTÁNICA)

José Revueltas, entre la realidad y la ficción: una lectura historiográfica de Los muros de agua

MELISSA MARCELA MARTINEZ LEMUS (2010, [Tesis de maestría])

157 páginas. Maestría en Historiografía.

En este trabajo se plantea un acercamiento historiográfico con una obra de ficción: Los muros de agua, de José Revueltas, para analizar la medida en que ésta puede ser susceptible a un análisis que recupere y dé cuenta de la historicidad inscrita en el entramado literario. Son varios los elementos que contribuyen a este fin, particularmente, el carácter testimonial de la obra que nos ocupa, así como el ser la primera novela publicada por el autor, convirtiéndola en su primer experimento literario formal. Se trata de acercarnos al autor, pero más que nada al contexto que éste vivió usando como principal objeto de estudio su obra, dejando al margen, — aunque no por ello ignorados— lo que otros autores dicen de él, pues “(Ése es) el problema de los escritores que están sobre todo en sus libros y ahí hay que ir a buscarlos antes que a ninguna otra parte”. El trabajo es un análisis interpretativo que se basa en la visión de Gadamer, sobre el círculo hermenéutico, así como en la visión de Geertz sobre la descripción densa, desde una perspectiva historiográfica donde, a partir del análisis de una novela, se demuestren las posibilidades del relato de ficción para un estudio historiográfico.

Historiography--Mexico. Literature and history. Revueltas, José, 1914-1976--Criticism and interpretation. Historiografía. Literatura e historia. Autores mexicanos. F1224 CIENCIAS SOCIALES HISTORIA HISTORIA GENERAL HISTORIOGRAFÍA

El duraznillo (Tapirira mexicana): una especie comestible poco conocida

Leonardo Díaz Sánchez CESAR ISIDRO CARVAJAL HERNANDEZ ELIA NORA AQUINO BOLAÑOS MARIA DEL SOCORRO HERRERA MEZA (2023, [Artículo])

Tapirira mexicana es un árbol de la familia Anacardiaceae (familia del mango), que se conoce como “duraznillo” o “huichini” (entre otros nombres comunes). En algunos lugares de México se consume la semilla como alimento secundario. Las semillas contienen ácidos grasos poliinsaturados y monoinsaturados cuyo potencial alimenticio y efectos en el organismo humano se desconocen. Resaltamos la importancia de Tapirira mexicana, en particular el consumo de sus semillas, una especie comestible que es poco valorada y reconocida en México.

ALIMENTO ANACARDIACEAE DURAZNILLO ESPECIE MEXICANA SEMILLAS BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL