SIMULACIÓN DE SISTEMAS PRODUCTIVOS NO BALANCEADOS: APLICACIÓN A LA PRODUCCIÓN DE MEZCAL (SIMULATION OF NONBALANCED PRODUCTION SYSTEMS: APPLICATION TO MEZCAL PRODUCTION)

ResumenLa simulación es aplicable a diferentes ramas técnicas del saber humano y por ende a sistemas administrativos y de negocios. El contexto de su tratamiento permite lograr importantes ahorros y es una herramienta poderosa de apoyo para la toma de decisiones bajo la representación de diferentes escenarios y lapsos de tiempo donde los sistemas se tornan complejos por la gran cantidad de variables que en estos interactúan.Este proyecto expone el método para la construcción de un modelo de simulación mediante el software ProModel para analizar sistemas de producción no balanceados en la industria de bebidas alcohólicas. El modelo asume que, los tiempos de proceso son deterministas. El estudio incluye una revisión de la literatura, conceptos de modelado y simulación, áreas de aplicación, análisis de datos, construcción de un modelo de simulación y análisis de resultados. Como conclusión, los datos indican que un pequeño aumento en la capacidad de algunos equipos, se traduciría en un mayor desempeño del sistema.Palabras Clave: Modelo, Simulación, ProModel, Sistemas de Producción No Balanceados. Abstract The simulation is applicable to different technical branches of human knowledge and therefore to administrative and business systems. The context of its treatment allows to achieve important savings and is a powerful support tool for decision making under the representation of different scenarios and time lapses where systems become complex due to the large number of variables that interact in them.This project exposes the method for the construction of a simulation model using ProModel software to analyze unbalanced production systems, applied in a Mezcal production plant. The model assumes that, the process times are deterministic. The study includes a review of the literature, concepts of modeling and simulation, areas of application, data analysis, construction of a simulation model and analysis of results. In conclusion, the data indicate that an increase in the capacity of some equipment, would result in a better performance of the system.Keywords: Mezcal, Model, Simulation, ProModel, Unbalanced Production Systems

DESARROLLO DE SECADORES SOLARES HIBRIDOS CON CONTROL INTELIGENTE PARA LA OPTIMIZACION DEL USO DE ENERGIA (DEVELOPMENT OF HYBRID SOLAR DRYERS WITH INTELLIGENT CONTROL TO OPTIMIZE ENERGY USE)

Resumen En la actualidad, la demanda de alimentos se ha incrementado sustancialmente en los países en desarrollo. Por otro lado, una tercera parte de los alimentos producidos son no consumidos, generando pérdidas y desperdicios en las cadenas de producción. Como línea de investigación, se considera la valorización de pérdidas y desperdicios de alimentos a través del desarrollo y mejora de productos y procesos destinados hacia la alimentación humana y ganadera siguiendo la filosofía de la “Producción más Limpia”. EL consumo energético en el secado industrial de alimentos se encuentra en el intervalo de 3 a 16 MJ por kilogramo de agua evaporada, con un costo de producción aproximado de $4.71 a$25.13 por la deshidratación de un kilogramo de producto seco en consumo de energía eléctrica. Actualmente se desarrolla un secador hibrido, que para una carga de 10 Kg de vegetales frescos en operación por lote consume 5.66 MJ de energía eléctrica por kilogramo de agua evaporada. Se postula que el consumo energético puede abatirse a través de un sistema control y administración de la energía. Palabras Clave: Calidad de secado, caracterización, controlador, secador hibrido solar-eléctrico, monitoreo. Abstract Actuality, the demand for food has increased substantially in developing countries. On other hand, a third part of the food produced is not consumed, generating losses and waste in production chains. How investigation line, the valuation of food losses and waste is considered through the development and improvement of products and processes destinated for human and livestock feeding, following the “cleaner production” philosophy. The energy consumption in the industrial drying of food is in the range of 3 to 16 MJ per kilogram of evaporated water, with an approximate production cost of $4.71 to$25.13 for the dehydration of one kilogram of dry product in electrical energy consumption. Currently a hybrid dryer is being developed, which for a load of 10 Kg of fresh vegetables in operation per batch consume 5.66 MJ of electrical energy per kilogram of evaporated water. It is postulated that energy consumption can be reduced through an energy management and control system. Keywords: Characterization, controller, drying quality, hybrid dryer solar-electric, monitoring

ANÁLISIS DE LAS VARIABLES DE DISEÑO DE UN COLECTOR SOLAR IMPLEMENTADO PARA EL PROCESO DE SECADO DE ALIMENTOS (ANALYSIS OF THE DESIGN VARIABLES OF A SOLAR COLLECTOR IMPLEMENTED FOR DRYING FOOD PROCESS)

Resumen En este proyecto se analizaron las variables de diseño de un colector solar mediante herramientas estadísticas y de dinámica de fluidos computacional, para ello fue necesario realizar experimentos, de esta manera se obtuvo un registro de las temperaturas que alcanza el colector bajo diferentes configuraciones dadas por el arreglo ortogonal Taguchi; estos experimentos son la base para analizar el comportamiento del colector solar, una vez obtenidas las temperaturas se calculó la eficiencia del colector solar para almacenar energía térmica. Estos datos se utilizan para conocer la varianza que existe entre los factores, así como para conocer el nivel de cada factor que contribuye a una mejor eficiencia. De esta manera se obtuvo un incremento del 10% en la eficiencia térmica del colector. Este colector fue acoplado a un sistema de secado de alimentos para un funcionamiento hibrido eléctrico-solar usando un sistema de control encargado de dosificar la energía. El colector redujo en un 27% el consumo energético durante el secado de producto cítrico en operaciones de hasta 24 horas. Palabras Clave: Captación solar, Colector híbrido eléctrico-solar, control, secador. Abstract In this project the design variables of a solar collector will be analyzed using statistical tools and computational fluid dynamics, so that is necessary to perform experiments, in this way a record of the temperatures reached by the collector was obtained under different configurations given by the orthogonal arrangement Taguchi; these experiments are the basis for analyzing the behavior of the solar collector, once the temperatures are obtained, the efficiency of the solar collector for thermal energy is calculated. These data are used to know the variety that exists between the factors, as well as to know the level of each factor that contributes to improve efficiency. In this way increase 10% the thermal efficiency on the collector. This collector was coupled to a food drying machine for an electric-solar hybrid operation using a control system responsible for dosing energy. The collector reduced energy consumption by 27% during drying of the citrus product in operations above 24 hours. Keywords: Solar collection, electric-solar hybrid collector, control, dryer

REVISIÓN DE LA APLICACIÓN DE HARDWARE IN THE LOOP EN SISTEMAS FOTOVOLTAICOS (REVIEW OF THE HARDWARE IN THE LOOP APPLICATION IN PHOTOVOLTAIC SYSTEMS)

Resumen En los últimos años los sistemas de distribución eléctricos se han ido transformando. Las micro-redes se presentan como una alternativa capaz de cubrir las necesidades que esta transformación implica, convirtiéndolas en el tema de investigaciones recientes. Uno de los aspectos tratados en estas investigaciones refiere a los medios de producción de energía limpia y en este punto la energía fotovoltaica destaca. La infraestructura y recursos necesarios para probar sistemas fotovoltaicos han motivado a la búsqueda de alternativas para llevar a cabo este proceso. Una de las soluciones radica en la implementación de simulaciones Hardware in the Loop. En este trabajo se presenta una revisión de investigaciones referentes a la aplicación de técnicas Hardware in the Loop en sistemas fotovoltaicos. Catorce investigaciones fueron sistematizadas recabando lo referente a cuatro aspectos: el tipo de hardware empleado, las ventajas y desventajas de la propuesta, la finalidad con la que fue llevada a cabo la investigación y el tipo de simulación HIL llevada a cabo. Palabras Clave: Controller Hardware in the Loop, Hardware in the Loop, Power Hardware in the Loop, Sistema fotovoltaico. Abstract In the last years, electrical distribution systems have transformed. Micro-grids are presented as a viable alternative to meet the needs that this transformation implies, converting them in the topic of interest in recent investigations. One of the aspects treated in these investigations refers to the means of clean energy production and, in this point, photovoltaic energy stands out. Infrastructure and resources needed for photovoltaic systems testing have motivated the research of alternatives to carry out this process. One of the solutions lies on Hardware in the Loop simulations applied in photovoltaic systems. Fourteen investigations collected systematically what refers to four aspects: the kind of hardware employed, the advantages and disadvantages of the proposal, the finality of the investigation and, finally, the kind of HIL simulation that was carried out. Keywords: Controller Hardware in the Loop, Hardware in the Loop, Photovoltaic system, Power Hardware in the Loop

Current and prospective situation of municipal solid waste final disposal in Mexico: A spatio-temporal evaluation

Mexico, similarly to other developing countries, has planned landfilling as the central technology to manage municipal solid waste (MSW). In this research, the current and future situation of final disposal of MSW in Mexico was studied, focusing on the spatial and temporal evaluation of final disposal sites (FDS), landfill gas (LFG) emissions, and potential power generation in an 80-year horizon. Geographic information systems were applied for spatial evaluation. The Mexico LFG 2.0 model was used to estimate the LFG emissions in 1782 FDS in operation, considering statal MSW characteristics and local FDS features. The transition towards a MSW management system that is less dependent on final disposal was carried out via a sensitivity analysis of the reduction of FDS in LFG emissions, power generation, and greenhouse gases (GHG) emissions. The study estimated that Mexico had an LFG generation of 2298 Mm3 in 2020, where only 4.6% of FDS were suited for power generation, up to 2534 GWh y-1. This electricity can avoid the emission of 1.45 Mt CO2 , since fossil fuels are predominant in the Mexican power grid. The sensitivity analysis showed that suppressing MSW landfilling could reduce 1636 Mt CO2 eq over the period studied compared to the business-as-usual scenario. The power generation potential of LFG has been used scarcely (165 GWh y-1). Public policies may focus on proposing economic incentives and establishing conditions for a biogas market, increasing the number of SL that use LFG for energy purposes

Main changes on the polyphenols profile and antioxidant capacity in Manila mango (Mangifera indica L.)

Mango is the second most commercialized tropical fruit in the world, and Mexico is the major exporter. In terms of mango production, Manila´s variety represents a quarter of the total mangoes production in Mexico. However, the changes that occur on the phenolic compounds during the Manila mango ripening process are unknown. Quantitative analysis of the major phenolic compounds was conducted at different maturity stages, using several spectrophotometric measurements and by high-performance liquid chromatography (HPLC). At the late ripening stage was observed the biggest content in pulp and peel of total phenols (577 and 10547 mg EAG /100 g), flavonoids (95.33 and 537 mg EQ/100 g), and antioxidant capacity by DPPH (25 and 347 mmol TE/100 g). Some bioactive compounds achieve their highest values at optimal consumption ripening. Although they diminish when the fruit reaches a senescence appearance. This is the first study to prove that mangiferin by itself shows a higher correlation in antioxidant capacity compared to other phenolic compounds in mango peel, and this suggest that phenolic compounds may have an important role in the postharvest antioxidant metabolism in Manila mango fruit. On the other hand, the results show that the peel compared to the pulp contains higher amounts of total phenols, flavonoids, gallic acid, mangiferin and antioxidant capacity, so its use as an ingredient in the preparation of functional food products is recommended. More studies are needed to go in-depth in the changes of the content of phytochemicals during the ripening process in the peel and pulp mango, which ones could be caused by the hormones responsible for ripening in the fruit, such as ethylene, and bioavailability of these compounds at different stages of maturation.El mango es la segunda fruta tropical más comercializada del mundo y México es el principal exportador. En términos de producción de mango, la variedad Manila representa una cuarta parte de la producción total de mangos en México. Sin embargo, se desconocen los cambios que ocurren en los compuestos fenólicos durante el proceso de maduración del mango Manila. El análisis cuantitativo de los principales compuestos fenólicos se realizó en diferentes etapas de madurez, utilizando varias medidas espectrofotométricas y mediante cromatografía líquida de alta resolución (HPLC). En la etapa de madurez tardía se observó el mayor contenido en pulpa y cáscara de fenoles totales (577 y 10547 mg EAG / 100 g), flavonoides (95.33 y 537 mg EQ / 100 g) y capacidad antioxidante por DPPH (25 y 347 mmol TE / 100 g). Algunos compuestos bioactivos alcanzan sus valores más altos en el punto de madurez óptima. Aunque disminuyen cuando el fruto adquiere una apariencia de senescencia. Este es el primer estudio que demuestra que la mangiferina por sí misma presenta una alta correlación con la capacidad antioxidante en comparación con otros compuestos fenólicos de la cáscara de mango, y esto sugiere que los compuestos fenólicos pueden tener un papel importante en el metabolismo antioxidante postcosecha en el mango Manila. Por otro lado, los resultados muestran que la cáscara comparada con la pulpa contiene mayores cantidades de fenoles totales, flavonoides, ácido gálico, mangiferin y capacidad antioxidante por DPPH, por lo que se recomienda su uso como ingrediente en la elaboración de productos alimenticios fucionales. Se necesitan más estudios para profundizar en los cambios del contenido de fitoquímicos durante el proceso de maduración en la cáscara y pulpa del mango, los cuáles podrían ser provocados por las hormonas responsables de la maduración en el fruto, como el etileno, y la biodisponibilidad de estos compuestos en diferentes etapas de maduración

The role of livestock feed fertilization as an improvement of sustainability in the dairy sector

International audienceFertilization of crops used as feed in the dairy industry represents up to 50% of greenhouse gases and 30% of its milk production costs. The environmental impacts of this activity are associated with the industrial production of fertilizers, their application to crops, and tillage practices. Proper fertilizer selection for feed production is an alternative to increase the sustainability of the dairy industry. This research evaluated the environmental and economic impact of optimizing crop fertilizer doses with a parametric linear programming model. The environmental impact and prices of fertilizers were evaluated following the life cycle assessment methodology and governmental information in a representative supply chain of the Mexican Bajio region. Optimization results show that if an N–P–K dose prioritizes using the most economical fertilizers in the region, the potential savings in fertilizer costs will reach 29.6 MUSD y-1 compared to conventional fertilization. Comparing the results with conventional fertilization strategies, reductions in greenhouse gas emissions of 22 g CO2 eq per kg of milk can be achieved, achieving up to 2.2% of Mexico's commitments in the COP21 agreement for the livestock sector. Optimal use of fertilizers from an economic and environmental perspective contributes to sustainable dairy production

Application of a sustainable location index approach to landfill site selection in Monterrey, Mexico

Landfilling is the main method to manage municipal solid waste (MSW) in Latin America due to the economic, technological and political characteristics of the region. The disposal of MSW in landfill sites may affect the quality of the environment and compromise a considerable share of the municipal budgets. The selection of suitable sites reduces the environmental and economic impact of landfills. In the present study the sustainable location index (SLI) is proposed as a methodology to assess environmentally, and economically, sanitary landfill site selection in the Metropolitan Area of Monterrey, a representative large-size city of Latin America. EVIAVE methodology was modified to include administrative and economic dimensions, which are assessed as a sustainable approach using together the SLI integrated with geospatial and multicriteria analysis tools. The assessment showed that the zones with the lowest SLI changes drastically when the importance of the economic or environmental factor varies. This result suggest that the inclusion of sustainability in landfill site selection decision-making is complex and it may requires the inclusion of local particularities such as municipal budgets, policies of MSW management and public perception about environmental deterioration

Current Status of Optical Systems for Measuring Lycopene Content in Fruits: Review

Optical systems are used for analysing the internal composition and the external properties in food. The measurement of the lycopene content in fruits and vegetables is important because of its benefits to human health. Lycopene prevents cardiovascular diseases, cataracts, cancer, osteoporosis, male infertility, and peritonitis. Among the optical systems focused on the estimation and identification of lycopene molecule are high-performance liquid chromatography (HPLC), the colorimeter, infrared near NIR spectroscopy, UV-VIS spectroscopy, Raman spectroscopy, and the systems of multispectral imaging (MSI) and hyperspectral imaging (HSI). The main objective of this paper is to present a review of the current state of optical systems used to measure lycopene in fruits. It also reports important factors to be considered in order to improve the design and implementation of those optical systems. Finally, it was observed that measurements with HPLC and spectrophotometry present the best results but use toxic solvents and require specialized personnel for their use. Moreover, another widely used technique is colorimetry, which correlates the lycopene content using color descriptors, typically those of CIELAB. Likewise, it was identified that spectroscopic techniques and multispectral images are gaining importance because they are fast and non-invasive

The use of broccoli agro-industrial waste in dairy cattle diet for environmental mitigation

Livestock feed production for the intensive dairy industry has a significant environmental impact. This study evaluated the potential to reduce the environmental impacts of milk production in Guanajuato, Mexico, by incorporating broccoli stems (BS), an abundant agro-industrial waste product with high nutritional value, into dairy cattle feed. The potential reduction of environmental impacts from adding BS to cattle diet formulation was estimated using a life cycle assessment and a linear programming model which considered nutritional requirements as constraints. Two scenarios for milk production were considered: an optimized conventional diet and an optimized diet including BS. The results indicated that incorporating BS in cattle feed could reduce greenhouse gas emissions by 118 g CO2 eq kg−1 fat-and-protein corrected milk (FPCM and agricultural land occupation by 0.002 m2a kg−1 FPCM but increased fossil depletion by 4 g oil eq kg−1 FPCM. BS can replace 11.1% of conventional feeds and maximize the incorporation feeds with low environmental impacts in the diet, such as alfalfa hay and maize silage. A sensitivity analysis of the economic allocation showed that the maximum price of BS to remain environmentally viable was 19.28 USD t−1 on a fresh matter basis