Abstract: This investigation studied the energy efficiency of a steam system in a hospital, considering the procedure in ASME EA-3-2009 standard. This is the standard for the energy assessment of industrial steam systems and aims to enhance the energy efficiency and sustainability of industrial steam systems by identifying opportunities and providing recommendations to optimize system performance. The obtained boiler energy efficiency was 80.29 %, by applying an energy balance, reaching 15.33 kW for heat losses in the distribution pipes. Two consistent improvement alternatives were proposed, starting by unifying the pipe diameter of the kitchen area of 5 m, generating a reduction of heat loss from 828 to 600 W, which represented a total annual energy saving of around 2.4 GJ/year. The investment cost is USD 47.40, considering the achievement of the break-even point after 9 months, where the insulation of the pipes with glass wool was considered second and it generated a reduction in losses of 5.98 kW, representing a total annual energy saving of about 62.91 GJ/year, which corresponds to approximately USD 1 672. The expenditure for insulating a 49 m pipe amounted to USD 462, factoring in both the NPV calculation and potential savings. The breakeven point was achieved within roughly 4 months, underscoring the economic advantage of implementing the two suggested improvement measures.

Resumen: En esta investigación se analizó la eficiencia energética de un sistema de vapor en un hospital, considerando la norma ASME EA-3-2009. Esta norma se utiliza para la evaluación energética de los sistemas de vapor industriales y busca mejorar la eficiencia energética y la sostenibilidad de estos sistemas identificando oportunidades y proponiendo medidas para optimizar el rendimiento. Se obtuvo una eficiencia energética de la caldera de 80.29 % mediante un balance de energías y las pérdidas de calor en las tuberías de distribución alcanzaron 15.33 kW. Se plantearon dos alternativas de mejora consistentes, iniciando con unificar el diámetro de tubería del área de cocina de 5 m, generando una reducción de pérdida de calor de 828 hasta 600 W, que representó un ahorro de energía anual total de 2.4 GJ/año, aproximadamente. El costo de inversión es de USD 47.40, considerando como alcanzable el punto de equilibrio a los 9 meses, donde se planteó en segundo lugar el aislamiento de las tuberías mediante lana de vidrio y generó la disminución de pérdidas en 5.98 kW, representando un ahorro de energía anual total de alrededor de 62.91 GJ/año, lo que corresponde a USD 1 672, aproximadamente. La inversión para el aislamiento de tuberías con una longitud de 49 m fue de USD 462, considerando el cálculo del VAN y los posibles ahorros, además el punto de equilibrio se alcanza a los 4 meses, aproximadamente, e indica el beneficio económico de aplicar las dos opciones de mejora planteadas.

Abstract: Vertical roller mills, (VRM), are widely used for grinding raw materials in factories engaged in the extraction and processing of minerals. Any machine used for grinding or crushing consumes around 30 to 40% of the energy of a factory. The loading pressure, table rotation speed, moisture content, outlet temperature and pressure rollers are variables that can be controlled to decrease the specific energy consumption Ecs. This paper poses an optimization problem in order to reduce the energy consumption of a VRM used to produce cement and to find the optimal parameters of the operating variables. Several packages are used to solve the nonlinear programming problem, with very good results in terms of accuracy and speed of convergence, but those provided by the Pyomo package are used because it obtains more accurate results. Comparing the result of the objective function with the energy consumption of a well-known cement company in Ecuador, it is concluded that the optimized parameters are able to reduce by 25% the energy consumption guaranteeing a minimum production of 2200 tons of cement per day, so the model is correctly validated.

Resumen: Los molinos verticales de rodillos (VRM), son máquinas muy utilizadas para moler materia prima en fábricas dedicadas a la extracción y procesamiento de minerales. Cualquier máquina ocupada para moler o triturar consume alrededor del 30 o 40% de la energía de una fábrica. La presión de carga, la velocidad de rotación de la mesa, el contenido de humedad, temperatura de salida del molino y presión de los rodillos son variables que se pueden controlar para disminuir el consumo de energía especifica (Ecs). Este trabajo plantea un problema de optimización con el fin de reducir el consumo energético de un VRM utilizado para producir cemento y encontrar los parámetros óptimos de las variables de operación. Se utilizan varios paquetes para resolver el problema de programación no lineal, obteniendo resultados muy buenos respecto a la precisión y velocidad de convergencia, pero se usan aquellos proporcionados por el paquete Pyomo ya que obtienen resultados más exactos. Comparando el resultado de la función objetivo con el consumo energético de una empresa cementera en Ecuador se concluye que los parámetros optimizados son capaces de reducir en un 25% el consumo energético garantizando una producción mínima de 2200 toneladas de cemento diarias por lo que el modelo se valida correctamente.

Abstract: This investigation compared the efficiency of a flat-plate solar collector with triangular and square geometry, by using the finite element method (FEM). The design of the geometries and the utilized parameters for the simulation were obtained from previous publications. SolidWorks was used to model the two collectors, meanwhile, the Fluent module of the ANSYS software was used for the simulation by the FEM. Collectors integrated a pipe of 7 mm internal diameter with a plate thickness of 11 mm; the defined material was aluminum. The experiment was conducted under ambient conditions at a temperature of 20 °C, accompanied by a solar radiation intensity of 1000 W·m-2. The heat transfer surfaces employed were 61 250 mm2 for the triangular collector and 122 500 mm2 for the square collector. The quality of the mesh was excellent, obtaining a skewness of 0.2486, with which efficiencies of 62 and 39 % and maximum temperatures of 27 and 25.5 °C were obtained for the triangular and square collectors, respectively. Due to the geometries performing as fins, the temperatures are higher in the corners and, therefore, achieving higher efficiency is impossible.

Resumen: En esta investigación, se comparó la eficiencia de un colector solar de placa plana con geometría triangular y cuadrada, a través del enfoque del método de elementos finitos (FEM, por sus siglas en inglés), se llevó a cabo la simulación. Las geometrías y los parámetros empleados en la simulación fueron extraídos de investigaciones previamente publicadas. Se utilizó el software SolidWorks para el modelado de los dos colectores, mientras que el módulo Fluent del software ANSYS fue utilizado para la simulación por el método FEM. Para los colectores se utilizó una tubería de 7 mm de diámetro interno, con un espesor de placa de 11 mm y de aluminio. Se consideró temperatura ambiente de 20 °C, con una radiación solar de 1000 W·m-2 y superficies de transferencia de calor 61 250 y 122 500 mm2 para el colector triangular y cuadrado, respectivamente. La calidad del mallado fue excelente, alcanzando skewness de 0.2486. De esta manera, luego del proceso de simulación se obtuvo eficiencias de 62 y 39 % y temperaturas máximas de 27 y 25.5 °C para el colector triangular y cuadrado, respectivamente. Debido a que las geometrías actúan como aletas, las temperaturas son más altas en las esquinas y por esto no es posible alcanzar mayor eficiencia.

Abstract: The results of a proposal for a high-efficiency photovoltaic system with multipurpose applications implemented along a road are presented. This system is designed to address issues related to lighting, telecommunications, and electric vehicle charging. The need for an isolated system arises from sudden power outages in the country that affect road safety and reliability, as well as the lack of phone signal in some areas. In the field of lighting, an analysis is conducted using DiaLux software to ensure compliance with appropriate lighting standards for different types of roads. Furthermore, the multipurpose system includes electric vehicle charging, which is becoming increasingly relevant due to the shift towards more eco-friendly vehicles. Providing electric vehicle charging along roads resolves the issue of limited electric vehicle range and promotes their reliable use. The evaluation of the energy resource using the Glover and McCulloch method is essential for designing an efficient system capable of meeting various user needs. Additionally, reducing carbon dioxide emissions is a significant consideration, as electric vehicles can significantly contribute to reducing greenhouse gas emissions compared to fossil fuel vehicles. Abstract highefficiency high efficiency presented telecommunications reliability areas Furthermore ecofriendly eco friendly use needs Additionally consideration

Resumen: Se presentan los resultados de una propuesta de un sistema fotovoltaico de alta eficiencia con aplicaciones multipropósito, implementado a lo largo de una carretera. Este sistema está diseñado para abordar cuestiones relacionadas con la iluminación, las telecomunicaciones y la carga de vehículos eléctricos. La necesidad de un sistema aislado surge de los apagones repentinos en el país que afectan la seguridad vial, el excesivo uso de vehículos de combustibles fósiles que emiten gases que contaminan el planeta, así como la falta de señal telefónica en algunas zonas. En el ámbito de la iluminación, se realiza un análisis utilizando el software DiaLux para garantizar el cumplimiento de los estándares adecuados de iluminación para diferentes tipos de carreteras. Además, el sistema multipropósito incluye la carga de vehículos eléctricos livianos de uso particular, que se está volviendo cada vez más relevante debido al cambio hacia vehículos más ecológicos. La provisión de carga de vehículos eléctricos a lo largo de las carreteras resuelve el problema de la autonomía limitada de los vehículos eléctricos y promueve su uso confiable. La evaluación del recurso energético mediante el método Glover y McCulloch es fundamental para diseñar un sistema eficiente capaz de satisfacer diversas necesidades del usuario. Además, la reducción de las emisiones de dióxido de carbono es un aspecto importante, ya que los vehículos eléctricos pueden contribuir significativamente a la reducción de las emisiones de gases de efecto invernadero en comparación con los vehículos de combustibles fósiles Resumen carretera vial planeta zonas Además particular ecológicos confiable usuario importante

Resumen La eficiencia técnica es una herramienta económica utilizada para determinar el uso de los recursos empresariales para mejorar su capacidad productiva. El objetivo fue establecer la relación existente entre los factores de la producción y la eficiencia técnica. La metodología para el análisis de la información obtenida se utilizó el análisis envolvente de datos (DEA) apoyado en los indicies de localización y de urbanización. Como resultados se evidenció que el rendimiento constante (CRS) más alto se ubica en el año 2016 y llega a 0,77046 y, el rendimiento variable (VRS) más representativo se presenta en el año 2018 con 0,97901. El índice de localización promedio es de 27,8402. En última instancia a través de un modelo econométrico se obtiene la relación directa entre las variables, para obtener un soporte más concreto en los resultados de la investigación. En conclusión, todas las empresas se ubican en la provincia de Pichicha exclusivamente y la eficiencia técnica tiene una relación directa con el capital incurrido (Ci) y la materia prima (Mp) además de los índices de localización y urbanización.

Abstract Technical efficiency is an economic tool used to determine the use of business resources to improve their productive capacity. The objective was to establish the relationship between production factors and technical efficiency. The methodology for the analysis of the information obtained was the data envelopment analysis (DEA) supported by the location and urbanization indexes. As results, it was evidenced that the highest constant return (CRS) is in the year 2016 and reaches 0.77046 and, the most representative variable return (VRS) is presented in the year 2018 with 0.97901. The average location index is 27.8402. Ultimately, through an econometric model, the direct relationship between the variables is obtained, to obtain a more concrete support in the results of the investigation. In conclusion, all the companies are in the province of Pichincha exclusively and technical efficiency has a direct relationship with the capital incurred (Ci) and the raw material (Mp) in addition to the location and urbanization indices.

Resumen: El método de disparo es una técnica iterativa que usa velocidad de disparo para obtener una solución óptima. El propósito de la investigación es verificar la eficacia de las iteraciones de Newton de orden 3 adaptadas y acopladas a RK4, en el método disparo. Se realizó un experimento numérico con ejemplos mediante el método de disparo en las ecuaciones diferenciales ordinarias no lineal de orden 2, y se obtuvo velocidades de disparo y errores en cada iteración. Los resultados obtenidos sobre velocidades finales fueron satisfactorios con las iteraciones NW, NWO3-1, NWO3-2 y NWO3-3 aplicadas al método de disparo y de los cuales, NWO3-2 y NWO3-3 tienen alta precisión en los experimentos realizados.

Abstract: The shooting method is an iterative technique that uses shooting speed to obtain an optimal solution. The purpose of the research is to verify the effectiveness of Newton iterations of order 3 adapted and coupled to RK4, in the shooting method. Numerical experiments were performed with examples using the shooting method in nonlinear ordinary differential equations of order 2, and shooting velocities and errors were obtained in each iteration. The results obtained on final velocities were satisfactory with the iterations NW, NWO3-1, NWO3-2 and NWO3-3 applied to the shooting method and of which, NWO3-2 and NWO3-3 have high accuracy in the experiments performed.

RESUMEN El estudio se realizó en la finca Tío Pedro en el municipio de Venezuela, en la provincia de Ciego de Ávila, tuvo como objetivo proponer modelos matemáticos para estimar los parámetros hidráulicos de un sistema de bombeo utilizando la técnica de riego por surcos para el cultivo del frijol negro. Los resultados mostraron fluctuaciones esperadas en los parámetros hidráulicos como caudal, carga, potencia hidráulica, tiempo de bombeo y volumen bombeado. Se encontraron relaciones funcionales entre el caudal y la carga de bombeo, así como entre la potencia hidráulica, el caudal y la carga de bombeo. Estas relaciones pueden mejorar el funcionamiento del sistema de bombeo, ahorrar energía y aumentar la eficiencia de la bomba. Además, se desarrollaron funciones para predecir las curvas características de la carga, la eficiencia de la bomba y del sistema en general. Estos resultados pueden mejorar la eficiencia energética y la gestión del agua en la agricultura.

ABSTRACT The study was carried out at the Tío Pedro farm in the municipality of Venezuela, in the province of Ciego de Ávila, with the objective of proposing mathematical models to estimate the hydraulic parameters of a pumping system using the furrow irrigation technique for the cultivation of black bean. The results showed expected fluctuations in hydraulic parameters such as flow rate, head, hydraulic power, pumping time, and pumped volume. Functional relationships were found between flow and pumping head, as well as between hydraulic power, flow and pumping head. These ratios can improve pump system performance, save energy, and increase pump efficiency. In addition, functions were developed to predict the characteristic curves of the load, the efficiency of the pump and the system in general. These results can improve energy efficiency and water management in agriculture.

Abstract The study analyzes the level of technical efficiency of public investment in Education at the primary and secondary level in Peru, 2016 to 2022. Data envelopment analysis - DEA was used and for the association between the provision of resources and educational quality. the panel data fixed effects model. The results indicate that there are relative differences in efficiency between the regions, registering an average score of 49% for the primary level and 38% for the secondary level, with the most efficient being Moquegua, Tacna, Arequipa and Ica, and the least efficient being Loreto, Huánuco, Ucayali, and San Martín. From the input-output association, classroom size, infrastructure in good condition and public investment have a direct relationship, while students per teacher and per computer, the relationship is inverse with respect to educational achievement in communication and mathematics at the primary and secondary level. This suggests that inefficient regions should increase educational attainment at the primary and secondary levels by an average of 51% and 62%, respectively, while maintaining the same level of spending. Therefore, to improve their efficiency within the framework of public policies, they can adopt the management implemented by regions such as Moquegua and Tacna.

Resumen El estudio analiza el nivel de eficiencia técnica de la inversión pública en Educación en el nivel primario y secundario en Perú, 2016 a 2022. Se utilizó el análisis envolvente de datos - DEA y para la asociación entre la dotación de recursos y la calidad educativa, el modelo panel data efectos fijos. Los resultados indican que existen diferencias relativas de eficiencia entre las regiones, registrando una puntuación promedio de 49 % para el nivel primario y 38 % para el nivel secundario, siendo los más eficientes Moquegua, Tacna, Arequipa e Ica, y los menos eficientes Loreto, Huánuco, Ucayali, y San Martín. De la asociación insumo - producto, tamaño del aula, infraestructura en buen estado e inversión pública tienen relación directa, en tanto que alumnos por docente y por computadora, la relación es inversa respecto al logro educativo en comunicación y matemática a nivel primario y secundario. Ello sugiere que las regiones ineficientes deben aumentar en promedio 51 % y 62 % los logros educativos en el nivel primario y secundario respectivamente, manteniendo el mismo nivel de gasto. Por tanto, para mejorar su eficiencia en el marco de políticas públicas, pueden adoptar la gestión implementada por las regiones como Moquegua y Tacna.

Resumo A cultura do milho, por sua fácil adaptação aos mais diversos agroecossistemas, se espalha por diferentes regiões do mundo, tornando-se uma das mais importantes culturas agrícolas. Nesta cultura, os insetos-praga se destacam por causar prejuízos tanto no campo quanto nos armazéns. A aplicação de óleos essenciais pode ser uma importante técnica a ser investigada no manejo de insetos devido à sua conhecida atividade inseticida e baixo risco o meio ambiente. O objetivo do deste trabalho foi avaliar o efeito inseticida e repelente de óleos essenciais de capim-limão exótico (Cymbopogon citratus) e capim-limão nativo (Elionurus sp.) para o manejo do gorgulho do milho (Sitophilus zeamais (Mots., 1855, Coleoptera: Curculionidae). A análise química dos óleos feita por CG-MS mostrou que a composição química do capim-limão nativo e exótico é semelhante, entretanto, as espécies exóticas apresentaram maior número de compostos. Os óleos essenciais de capim-limão nativo e exótico têm eficiência na mortalidade do gorgulho do milho, e verifica-se que o aumento na dose aplicada reflete na redução do tempo de exposição do inseto até que ocorra a morte. O óleo essencial de ambas as espécies apresentou capacidade repelente em todos os momentos avaliados. Assim, pode-se afirmar que ambas as espécies possuem capacidade e potencial para serem utilizadas no manejo do gorgulho do milho, podendo ser uma alternativa para a agricultura familiar e produção orgânica.

Abstract Corn crop, due to its easy adaptation to the most diverse agroecosystems, spreads throughout the different regions of the world, making it one of the most important agricultural crops. In this crop, pest insects stand out for causing losses both in the field and in warehouses. The application of essential oils can be an important technique to be investigated in the management of insects due to its known insecticidal activity and low risk to the environment. The objective of the work was to value the insecticide and repellent effect of essential oils of exotic lemongrass (Cymbopogon citratus) and native lemongrass (Elionurus sp.) for the management of maize weevil (Sitophilus zeamais (Mots., 1855, Coleoptera: Curculionidae)). The chemical analysis of the oils made by CG-MS showed that the chemical composition of the native and exotic lemongrass is similar, however, the exotic species presented a greater number of compounds. The essential oils of native and exotic lemon grass have efficiency on maize weevil mortality, and it is verified that the increase in the applied dose reflects in a reduction in the insect's exposure time for death to occur. The essential oil of both species showed repellent capacity at all times evaluated. Thus, it can be said that both species have the capacity and potential to be used in the management of corn weevil, and can be an alternative for smallhorders farmers and organic production.

Resumo A produção de plantas transgênicas com características agronômicas e hortícolas desejadas vem ganhando grande importância por atender às demandas da crescente população. A transformação genética também é um passo fundamental para estudar os fundamentos das ciências das plantas. Foram desenvolvidos e utilizados diferentes protocolos de transformação, que são confiáveis e eficientes. Esses protocolos usaram genes de resistência a antibióticos ou herbicidas incorporados ao gene de interesse para identificar plantas transformadas e não transformadas. Esses genes marcadores podem representar uma ameaça ao ser humano e ao meio ambiente. O uso de marcadores visuais permite a observação direta e fácil de plantas transformadas com mais precisão. No estudo atual, foi projetado um cassete de genes com o gene da hidroxilase de produção de pigmentos (PPH) sob promotor específico de fibra (GhSCFP) e terminador NOS a jusante. Após verificar a eficiência estrutural e funcional do gene otimizado por códons usando ferramentas de bioinformática, o cassete foi enviado para síntese química a partir de fonte comercial. O cassete do gene do pigmento (PPH_CEMB), clonado em pCAMBIA-1301, foi transformado em Agrobacterium por eletroporação. O método de imersão floral mediado por Agrobacterium foi usado para transformar a inflorescência de Camelina sativa. Após a formação de sementes, foi observado um total de 600 sementes com mudança de cor, das quais 19 desenvolveram uma coloração marrom-avermelhada, enquanto as 581 restantes permaneceram amarelas. A eficiência de transformação calculada com base na mudança de cor foi de 1%. A análise de PCR das folhas obtidas após a semeadura de sementes avermelhadas confirmou a transformação do gene produtor de pigmentos, enquanto não foi observada amplificação por PCR em folhas de plantas de sementes do tipo selvagem. A partir dos resultados, é evidente que a transformação da inflorescência de C. sativa mediada por Agrobacterium é uma técnica muito eficiente e favorável ao ambiente não só para a detecção de plantas transformadas, mas também para estudar processos celulares básicos.

Abstract Production of transgenic plants with desired agronomic and horticultural traits has gained great importance to fulfill demands of the growing population. Genetic transformation is also a fundamental step to study basics of plant sciences. Different transformation protocols have been developed and used which are reliable and efficient. These protocols used antibiotic or herbicide resistance genes incorporated along with gene of interest to identify transformed plants from non-transformed ones. These marker genes may pose a threat to human and environment. Use of visual markers enables direct and easier observation of transformed plants with more precision. In current study a gene cassette with ‘pigment production hydroxylase (PPH) gene under fiber specific promoter (GhSCFP) and downstream Nos-terminator was designed. After checking the structural and functional efficiency of codon optimized gene using bioinformatics tools, the cassette was sent for chemical synthesis from commercial source. The pigment gene cassette (PPH_CEMB), cloned in pCAMBIA-1301, was transformed into Agrobacterium through electroporation. Agrobacterium-mediated floral dip method was used to transform Camelina sativa inflorescence. After seed setting a total of 600 seed were observed for change in color and out of these, 19 seeds developed a reddish-brown coloration, while the remaining 581 seeds remained yellow. The transformation efficiency calculated on basis of color change was 1.0%. PCR analysis of leaves obtained after sowing reddish seeds confirmed the transformation of pigment production gene, while no PCR amplification was observed in leaves of plants from wild type seeds. From the results it is evident that Agrobacterium-mediated transformation of C. sativa inflorescence is very efficient and environment friendly technique not only for detection of transformed plants but also to study basic cellular processes.

Abstract: Family dairy farming is relevant for national agriculture which, although it contributes to the generation of wealth and income, faces low efficiency, productivity and high production costs. The objective was to analyze the technical efficiency of family dairy farms in the State of Minas Gerais. Data Envelopment Analysis (DEA) with input-oriented BCC model was used. The higher the efficiency level of the DMUs, the fewer resources were used in excess. It was also identified the lack of DMUs that performed preventive maintenance of machines, implements and improvements, justifying the increase in the use, mainly, of the MIB input (maintenance of machines, implements and improvements). With this research, the Milk Input Commitment Index (ICIL) was suggested, which shows the percentage of production that is committed to purchase a given input. The higher the efficiency level of the DMUs, the lower the ICIL, which went from 49.36% (efficient) to 67.47% (low efficiency). This proved to be an important indicator of efficiency of dairy properties, responsible for showing the amount of milk produced that is committed to the payment of inputs used in the dairy activity. It also proved to be a valuable instrument to be used as a benchmark in dairy farms.

Resumo: A pecuária leiteira familiar é relevante para a agropecuária nacional que, embora contribua com a geração de riqueza e renda, enfrenta baixas eficiência, produtividade e custos de produção elevados. Objetivou-se analisar a eficiência técnica de propriedades leiteiras familiares no Estado de Minas Gerais. Utilizou-se a Análise por Envoltória de Dados (DEA) com modelo BCC orientado a inputs. Quanto maior foi o nível de eficiência das DMU’s, menos recursos foram utilizados em excesso. Foi identificada, ainda, a inexistência de DMU’s que realizaram manutenção preventiva de máquinas, implementos e benfeitorias, justificando o aumento da utilização, principalmente, do insumo MIB (manutenção de máquinas, implementos e benfeitorias). Com esta pesquisa, sugeriu-se o Índice de Comprometimento de Insumos em Leite (ICIL), que evidencia o percentual da produção que está comprometida para comprar um determinado insumo. Quanto maior foi o nível de eficiência das DMU’s, menor foi o ICIL, que passou de 49,36% (eficientes) para 67,47% (com eficiência baixa). Este se mostrou um importante indicador de eficiência de propriedades leiteiras, responsável por evidenciar a quantidade de leite produzido que está comprometida com o pagamento dos insumos utilizados na atividade leiteira. Também se mostrou valioso instrumento a ser utilizado como benchmark em propriedades leiteiras.

ABSTRACT: Controlled machinery traffic is a technique to increase the efficiency of machines and make better use of inputs. This study evaluated the pollutant gas emissions of an agricultural tractor towing a precision seeder-fertilizer with different plow configurations in an area with varying intensities of controlled machinery traffic. The study was carried out in a commercial agricultural area located in the municipality of Carazinho, Brazil. The experimental design was of randomized 3 x 3 blocks, with three traffic situations (tractor traffic; tractor + harvester traffic; and tractor + harvester + sprayer traffic), as well as three plow settings. The pollutant gases analyzed were: particulate material (PM), nitrogen oxides (NOx), carbon dioxide (CO2), and oxygen (O2). We concluded that greater controlled traffic intensity, compared to an area without traffic, yields a PM reduction of 43% using the double disk, and 67% using the double disk without a ridge plow. The absence of plows on the traffic lines reduces the PM, NOx, and CO2 emissions by, respectively, 73%, 12%, and 17% with tractor + harvester traffic; and 80%, 12%, and 15% with tractor + harvester + sprayer traffic, compared to cultivation using ridge plows.

RESUMO: O tráfego controlado de máquinas é uma técnica para aumentar a eficiência das máquinas e melhor utilizar os insumos. O objetivo deste trabalho foi avaliar as emissões de gases poluentes de um trator agrícola tracionando uma semeadora-adubadora de precisão com diferentes configurações de sulcadores em uma área com intensidades variadas de tráfego controlado de máquinas. O estudo foi realizado em uma área agrícola comercial localizada no município de Carazinho, Brasil. O delineamento experimental foi em blocos casualizados 3 x 3, com três situações de tráfego (tráfego de trator; tráfego de trator + colheitadeira; e tráfego de trator + colheitadeira + pulverizador), além de três configurações de sulcadores. Os gases poluentes analisados foram: material particulado (MP), óxidos de nitrogênio (NOx), dióxido de carbono (CO2) e oxigênio (O2). Concluiu-se que a maior intensidade de tráfego controlado, em comparação com área sem tráfego, proporciona redução de MP de 43% usando o disco duplo e 67% usando o disco duplo sem haste. A ausência de sulcadores nas faixas de tráfego reduz as emissões de MP, NOx e CO2 em 73%, 12% e 17% respectivamente, com tráfego trator + colheitadeira e 80%, 12% e 15% com tráfego de trator + colheitadeira + pulverizador, em relação ao cultivo com sulcador haste.

ABSTRACT This research proposes to maximize the efficiency of an energy capture system, through wind kites incorporating a flow pattern remediation technique, for the restoration of environmental conditions. The design method proposes a mathematical modeling in VHDL for the alignment angles (YPR: yaw, pitch, roll) of the wind collector array, to establish a cognitive system update technology, minimizing hardware components for active flow control. and reducing the environmental impact of wind turbines. The support equations are obtained as a function of optimization coefficients α,β,γ of the wind system, considering trajectories on cyclical curves and transmission by magnetic levitation, for the control, maintenance and reconfiguration of regenerative flow patterns. This allows us to conclude about the importance of designing remediation mechanisms such as vortex patterns from the control of outlet angles of the wind collector, in a commitment to obtain a sustainable system.

RESUMEN Esta investigación propone maximizar la eficiencia de un sistema captador de energía, a través de cometas eólicas incorporando una técnica de remediación del patrón de flujo, para el restablecimiento de las condiciones ambientales. El método de diseño plantea un modelado matemático en VHDL para los ángulos de alineación (YPR: yaw, pitch, roll) del arreglo de captadores eólicos, para establecer una tecnología cognitiva de actualización del sistema, minimizando los componentes hardware para el control activo de flujo y disminuyendo el impacto ambiental de los aerogeneradores. Se obtiene como resultado las ecuaciones de soporte en función de coeficientes de optimización α,β,γ del sistema eólico, considerando trayectorias sobre curvas cíclicas y transmisión por levitación magnética, para el control, mantenimiento y reconfiguración de patrones de flujo regenerativo. Esto permite concluir acerca de la importancia de diseñar mecanismos de remediación como patrones de vórtices a partir del control de ángulos de salida del captador eólico, en un compromiso por obtener un sistema sostenible.

Abstract The perspectives that associate urban development and transport bring together theories, practices and methods based on that joint approach; furthermore, they argue that urban growth models affect the efficiency of public transport. From this hypothesis, the objective of this article is to conduct a literature review of such proposals in order to gather international knowledge and experiences towards a comprehensive approach to the problem and the management of solutions in Latin America. The methodological approach is qualitative and based on the technique of documental analysis through using representative references from several disciplines, geographical contexts and cities scales.

Resumen Las perspectivas que vinculan desarrollo urbano y transporte reúnen teorías, prácticas y métodos sustentados en ese abordaje conjunto; además, argumentan que los modelos de crecimiento urbano inciden en la eficiencia del transporte público. Desde esta hipótesis, el objetivo del artículo es una revisión bibliográfica de tales propuestas, para reunir saberes y experiencias internacionales, a fin de avanzar hacia un planteo integral del problema y la gestión de soluciones en América Latina. El enfoque metodológico es cualitativo y se basa en la técnica del análisis documental, recurriendo a referencias representativas de diversas disciplinas, contextos geográficos y escalas de ciudades.

Resumen Introducción. La rentabilidad del sistema de doble propósito (SDP) está afectada por baja eficiencia productiva y altos costos de producción generados en el manejo tradicional. Estudios en función de la reducción de costos e incremento de los ingresos, podría sugerir estrategias para mejorar la eficiencia económica. Objetivo. Determinar la eficiencia técnica y rentabilidad de tres alternativas de producción del SDP bovino en Meta, Colombia. Materiales y métodos. El estudio se llevó a cabo durante el periodo 2016-2017, en una finca del departamento de Meta, Colombia. Se seleccionaron 72 vacas Bos taurus x Bos indicus, que iniciaban lactancia, alimentadas bajo pastoreo, las vacas seleccionadas y sus crías se distribuyeron en tres grupos: alternativa 1 (MA1): ordeño dos veces por semana hasta el destete a 100 días, alternativa 2 (MA2): ordeño dos veces por semana hasta el destete a 240 días y alternativa 3 (MT): ordeño diario (tradicional), hasta el destete a 240 días. En los terneros se midió el peso al nacimiento y a los 252 días de vida (P252), y se estimó la ganancia de peso diaria (GPD). En las vacas se midió la tasa de terneros nacidos por vaca/año (TN) y la leche producida por lactancia (LPL). Para el análisis económico, los resultados en cada tratamiento se proyectaron para un pie de cría de 100 vacas. Resultados. El P252 y la GPD de los grupos MA1 (189,30 kg; 0,64 kg/animal/día) y MA2 (186,10 kg; 0,63 kg/animal/día) fue similar (p>0,05), pero superiores (p<0,05) a los del MT (155,10 kg; 0,54 kg/animal/día). La TN fue mayor para MA1 (0,84 terneros/vaca/año), seguida por la del MA2 (0,74 terneros/vaca/año) y MT (0,68 terneros/vaca/año). La LPL fue de 1204,36 kg para MT, 303,74 kg para MA2 y 158,75 kg para MA1. La rentabilidad de MA1 superó en 9,5 y 9,2 % a MA2 y MT, respectivamente. Conclusiones. El ordeño dos veces por semana hasta el destete (MA1) reflejó mayor eficiencia económica por efecto del incremento en la tasa de terneros nacidos por vaca/año (TN) y disminución en los costos de producción.

Abstract Introduction. The profitability of the dual-purpose system (DPS) is affected by low production efficiency and high production costs generated in traditional management. Studies based on the reduction of expenses and increase of income, could suggest strategies to improve economic efficiency. Objective. Determine the technical and profitable efficiency of three production alternatives for bovine DPS in Meta, Colombia. Materials and methods. The study was conducted during 2016-2017, on a farm in the department of Meta, Colombia. Seventy-two Bos taurus x Bos indicus cows were selected, starting lactation, fed under grazing, during the period 2016-2017, in a farm in Meta, Colombia. The selected cows and their calves were distributed in three groups; alternative 1 (MA1): milking 2 times a week until weaning at 100 days, alternative 2 (MA2): milking 2 times a week until weaning at 240 days, and traditional (MT): milking daily (traditional) until weaning at 240 days. In the calves, the weight at birth and at 252 days of age (W252) were measured, and the daily weight gain (DWG) was estimated. In the cows, the birth rate (BR) and the milk produced per lactation (MPL) were measured. The productive response fed the economic analysis projected for a breeding stock of 100 cows. Results. The W252 and DWG between MA1 (189.30 kg; 0.64 kg/animal/day) and MA2 (186.10 kg; 0.63 kg/animal/day) groups were similar (P>0.05), but higher (p<0.05) than those of the MT (155.10 kg; 0.54 kg/animal/day). BR presented the highest benefit for MA1 (0.84 calves/cow/year), followed by MA2 (0.74 calves/cow/year), and MT (0.68 calves/cow/year). The MPL was 1204.36 kg for MT, 303.74 kg for MA2 and 158.75 kg for MA1. MA1's profitability outperformed MA2 and MT by 9.5 and 9.2 %, respectively. Conclusions. The MA1 reflected the greater economic efficiency mainly due to the effect of the increase in the BR and the decrease in production costs.