Papers by Rafael Perez Pupo
The management of scientific events in the universities has become a process of vital importance ... more The management of scientific events in the universities has become a process of vital importance for the socialization of the scientific-technological and innovative work of these institutions. It is also essential to contribute to their improvement and social relevancy; nevertheless, the existent theoretical and methodological foundations for its development are insufficient. In this article it is presented a methodology for the management of scientific events in these institutions, which improve significantly the indicators of this process. The methodology has been applied and validated in a Cuban university, and its effectiveness was verified through the main theoretical and empiric methods of investigation used. The methodology consists of three recurrent work phases, which are: i) conception and design, ii) development iii) evaluation and feedback. In each one of them is executed several stages. It is important to specify that in each step it is necessary to use multiple management tools. The methodology improves significantly the indicators of this process, and based on the results it contributes to significant improvement of indicators related with the management of scientific events and, consequently, the social relevancy of university increases. The originality and essential values proposed are sustained in its four qualities: systemic, flexible, participation and pro-active character.
Habitualmente el diseno y analisis de los sistemas hidraulicos es conducido de forma interactiva ... more Habitualmente el diseno y analisis de los sistemas hidraulicos es conducido de forma interactiva probando y modificando, lo cual conlleva a un esquema de circuito y el calculo de sus componentes y parametros del sistema. La simulacion hoy en dia es utilizada para analizar el comportamiento de los sistemas, investigando el rol de los parametros de diseno en las prestaciones del sistema. El programa de simulacion HOPSAN ha sido desarrollado en la division de hidraulica y sistemas mecanicos de la Universidad de Linkoping, Suecia desde 1977. Ha sido desde el principio un sistema para la modelacion, simulacion y analisis de sistemas hidraulicos. Los algoritmos de optimizacion que han sido implementados en HOPSAN proporcionan la posibilidad de optimizar el comportamiento del sistema, sujeto a restricciones. En el presente trabajo se simula y optimiza el sistema hidraulico de accionamiento del aparato trozador y discos de corte de la cosechadora de cana, valorandose la influencia de los pa...
European Scientific Journal, ESJ, Jul 31, 2018
The study allowed to determine the perceptions and characterization of the pastures in farms of l... more The study allowed to determine the perceptions and characterization of the pastures in farms of livestock producers and researchers in the Canton Sachas and Francisco Orellana, Province of Orellana, Ecuador, whose objective was to know the use and management of Amazonian tropical pastures. Seventeen cattle farms of 8 communities were characterized to observe the characterization of the farmers, land use, use of forage banks, pasture management and bovine cattle housing. A semi-structured interview was designed to collect primary information about the problem under investigation. When characterizing the farmers, in relation to land use, previously 47.5% of the producers were engaged in agriculture, today 85.9% carry out livestock work with silvopastoral practices and only 14.1% are dedicated to agriculture. production of coffee and cocoa. Regarding the use of feed banks, 35.29% have more food for their animals and 5.88% have better environmental conditions. In addition, 77.6% of the farmers mentioned that they have improved their production with the use of the feed bank. In summary, the results indicate that small and medium producers can benefit from silvopastoral systems as an alternative to improve production and not affect the environment.
European Scientific Journal, ESJ, Aug 31, 2018
This paper focuses on determining the perception and characterization of the pastures in the farm... more This paper focuses on determining the perception and characterization of the pastures in the farms of livestock producers and researchers in the Canton Sachas and Francisco Orellana, Province of Orellana, Ecuador. Their objective was to understand the use and management of Amazonian tropical pastures. Seventeen cattle farms of 8 communities were characterized to observe the characterization of the farmers, land use, use of forage banks, pasture management, and bovine cattle housing. A semi-structured interview was designed to collect primary information about the problem under investigation. When characterizing the farmers in relation to land use, before 47.5% of the producers were engaged in agriculture, today 85.9% carry out livestock work with silvopastoral practices. Only 14.1% were dedicated to agriculture and the production of coffee and cocoa. Regarding the use of feed banks, 35.29% have more food for their animals, while 5.88% have better environmental conditions. In addition, 77.6% of the farmers mentioned that they have improved their production with the use of the feed bank. In conclusion, the results indicate that small and medium producers can benefit from silvopastoral systems as an alternative to improve production and not affect the environment.
ESPOCH Congresses: The Ecuadorian Journal of S.T.E.A.M., 2021
All research responds to the need of solutions to a problem that directly or indirectly affects s... more All research responds to the need of solutions to a problem that directly or indirectly affects society. The development of the same largely certifies and determines the constant search for solutions. The main objective of the present study was to arrive at a clear conceptualization, as complete as possible, of some the most important terms that come up during an investigation design: Problematic Situation, Real Problem, Scientific Problem, and Object and Field, given the visible shortcomings observed in pre- and post-graduate theses when the research work is being developed and defended. The methodology consisted of basically developing a reflection around these terms (the vision that different authors have in this regard was very helpful), as well as the presentation of varied examples contributed to see the meaning of these important concepts more clearly. The study shows in a scientifically grounded way the achievement of the above. The way in which the presentation of the diffe...
Revista Ciencias Técnicas Agropecuarias, Mar 1, 2013
Revista Facultad De Ingenieria-universidad De Antioquia, 2020
Roberto Andrés Estrada Cingualbres1, Héctor Calzadilla Dubras2, José Martínez Grave de Peralta ... more Roberto Andrés Estrada Cingualbres1, Héctor Calzadilla Dubras2, José Martínez Grave de Peralta 3, Rafael Valera Llanes 2, Juan Rafael Pérez Pupo4* 1Centro de estudios CAD/CAM, Facultad de Mecánica, Universidad de Holguín. Avenida XX Aniversario. C. P. 80100. Holguín, Cuba. 2Centro de Desarrollo de la Maquinaria Agrícola (CEDEMA). C. P. 80100 Holguín, Cuba. 3Departamento de Mecánica Aplicada, Facultad de Ingeniería, Universidad de Holguín. Avenida XX Aniversario. C. P. 80100. Holguín, Cuba. 4Escuela Politécnica Superior del Chimborazo. Ent 1 ESPOCH. C. P. 060155. Riobamba, Ecuador.
In sugar cane mechanized harsverting, there are some peculiarity related to soil-machine-plant in... more In sugar cane mechanized harsverting, there are some peculiarity related to soil-machine-plant interaction which has been causing some concern due to raw material left on the field losses and the reduction in sugar cane crop longevity caused by deficiency in cut height control. Improvement in cut quality and raw material of the matter it prevails they are in the bibliography by means of the interventions in the crop and others practice cultural existent and of changes in the design of croppers. Devices have been developed for auxiliary to the operators in the control of the court height keeping in mind the importance of the base cut in the quality and lost of matter it prevails and in the longevity of the reed bed, the objective of this work was to validate the influence of a hydraulic device of control of the height of base court, SHC, in the quality of the base cut and its acting throughout the work day.
Revista Facultad de Ingeniería, Universidad de Antioquia, Aug 24, 2020
A linear dynamic study of the tensional status of the unloading conveyo ´s spin beam in the new m... more A linear dynamic study of the tensional status of the unloading conveyo ´s spin beam in the new model CCA-5000 Cuban sugarcane harvester is carried out. The dynamic coefficients were determined using a strain gauge experimental evaluation of the KTP-23 harvester, which is a similar model in structure to the CCA-5000. A finite elements analysis is used to obtain the safety distribution factor and the tensions in the beam for different load combinations linked to a dynamic variation curve of the loads. Aiming to verify the presence or not of large amplitudes on the system oscillations caused by the resonance phenomenon, an analysis of the frequency modes for each load status is conducted, and the results are compared with the terrain irregularities frequencies on which the harvester moves. Finally, taking into account the previous results, the shape of the beam is optimized in order to decrease its steel volume.
Revista Facultad de Ingeniería, Universidad de Antioquia , Aug 24, 2020
A linear dynamic study of the tensional status of the unloading conveyo ´s spin beam in the new m... more A linear dynamic study of the tensional status of the unloading conveyo ´s spin beam in the new model CCA-5000 Cuban sugarcane harvester is carried out. The dynamic coefficients were determined using a strain gauge experimental evaluation of the KTP-23 harvester, which is a similar model in structure to the CCA-5000. A finite elements analysis is used to obtain the safety distribution factor and the tensions in the beam for different load combinations linked to a dynamic variation curve of the loads. Aiming to verify the presence or not of large amplitudes on the system oscillations caused by the resonance phenomenon, an analysis of the frequency modes for each load status is conducted, and the results are compared with the terrain irregularities frequencies on which the harvester moves. Finally, taking into account the previous results, the shape of the beam is optimized in order to decrease its steel volume.
European Scientific Journal ESJ
European Scientific Journal, ESJ
The study allowed to determine the perceptions and characterization of the pastures in farms of l... more The study allowed to determine the perceptions and characterization of the pastures in farms of livestock producers and researchers in the Canton Sachas and Francisco Orellana, Province of Orellana, Ecuador, whose objective was to know the use and management of Amazonian tropical pastures. Seventeen cattle farms of 8 communities were characterized to observe the characterization of the farmers, land use, use of forage banks, pasture management and bovine cattle housing. A semi-structured interview was designed to collect primary information about the problem under investigation. When characterizing the farmers, in relation to land use, previously 47.5% of the producers were engaged in agriculture, today 85.9% carry out livestock work with silvopastoral practices and only 14.1% are dedicated to agriculture. production of coffee and cocoa. Regarding the use of feed banks, 35.29% have more food for their animals and 5.88% have better environmental conditions. In addition, 77.6% of the ...
The present work describes in summarized form the design methodology of the hydraulic systems, co... more The present work describes in summarized form the design methodology of the hydraulic systems, considering the fundamental parameters of the hydraulic drive, the stages in which the same one must be made are: preliminary calculation and verification, selecting such in correspondence with the calculations of the moments, operating forces and speeds in the mechanisms as well as the algorithm of
Revista Ciencias Tecnicas Agropecuarias, 2006
Revista Ciencias Tecnicas Agropecuarias, 2008
... Experimental research of the dynamics of the working of the crosscutter of the sugar cane har... more ... Experimental research of the dynamics of the working of the crosscutter of the sugar cane harvester. Juan Rafael Pérez Pupo 1. ... REFERENCIAS BIBLIOGRÁFICAS. 1. LURIE A, B.: Dinámica estadística de los agregados agrícolas ( en ruso), Editorial Kolos, Leningrado, 1970. ...
Revista Ciencias Tecnicas Agropecuarias, Mar 1, 2012
Revista Ciencias Tecnicas Agropecuarias, Mar 1, 2013
Revista Ciencias Tecnicas Agropecuarias, 2007
ABSTRACT The present work describes in summarized form the design methodology of the hydraulic sy... more ABSTRACT The present work describes in summarized form the design methodology of the hydraulic systems, considering the fundamental parameters of the hydraulic drive, the stages in which the same one must be made are: preliminary calculation and verification, selecting such in correspondence with the calculations of the moments, operating forces and speeds in the mechanisms as well as the algorithm of design of the hydraulic systems. The calculations of the hydraulic systems are of great importance in the world of the design of the agricultural machinery since they serve for the correct selection of all the hydraulic devices, determination of the diameter of the pipe, etc, is for that reason that the calculations, as it regulates become in two stages: � First stage: The preliminary calculation is made (it includes the simplified static calculation and the selection of the components). � Second stage: The verification is made (it includes the modeling of the components and system with the analysis of the stationary regime and the dynamics of the system).
Uploads
Papers by Rafael Perez Pupo