Now showing items 1-20 of 25

Production of bioethanol from rice husk pretreated with alkalis and hydrolyzed with acid cellulase at pilot scale

Cacua Silva, Alejandra; RodrÍguez Ordoñez, Dora Cecilia; Parra LLanos, John Wilmer (Journal of Physics: Conference SeriesReino Unido, 2018-12-07)

Rice husk (RH) is the main biomass byproduct of the rice industry, so much that it corresponds to 20% of the total cereal production and is generally considered a waste. Due to its content of cellulose and hemicellulose, ...
Comparison of statistical forecasting techniques for Colombian coffee demand in South Korea

PALACIOS ALVARADO, WLAMYR; Rincón, R D; Paipa, H O (Journal of Physics: Conference SeriesReino Unido, 2019-03-06)

This article shows a comparison of various methods as a statistical technique for making applied forecasts of Colombian coffee demand in South Korea. The aim is to model the demand behavior in the most adjusted and efficient ...
La teoría de restricciones y la optimización como herramientas gerenciales para la programación de la producción. Una aplicación en la industria de muebles

Romero Rojas, Julian David; Ortiz Triana, Viviana Karolina; Caicedo-Rolón, Alvaro Jr (Revista de Métodos Cuantitativos para la Economía y la EmpresaEspaña, 2019-07-18)

La teoría de restricciones (TOC) es una filosofía de mejoramiento continuo, que se enfoca en el eslabón más débil de la cadena, para mejorar el desempeño del sistema productivo. El propósito de la investigación fue determinar ...
Modelo matemático para la planeación de la producción en una industria metalmecánica

Caicedo-Rolón, Alvaro Jr; Criado Alvarado, Angélica María; Morales Ramón, Kerly Jorleidhy (Scientia et TechnicaColombia, 2019-09-30)

La planeación de la producción es una decisión táctica a mediano plazo, que determina el nivel de trabajadores, inventarios y producción requeridos, para satisfacer la demanda en un horizonte de planeación. ...
Evaluation of mechanical wear in bismuth-titanium coatings synthesized by the sol-gel method and applied on 316 L stainless steel substrates

Aperador Chaparro, William Arnulfo; Bautista-Ruiz, Jorge; Garzon, P (Journal of Physics: Conference SeriesInglaterra, 2019-11)

Steels are part of the basic equipment of most of the industrial framework, including very diverse sectors such as the oil, chemical and automotive industries. However, steels are susceptible to wear phenomena limiting ...
Mathematical model for production sequencing in a manufacturing company

Parra LLanos, John Wilmer; Caicedo-Rolón, Alvaro Jr; RIVERA CADAVID, LEONARDO (Journal of Physics: Conference SeriesReino Unido, 2019-11-19)

The objective of the research was to determine the optimal sequence of production of n jobs in m operations, in a small footwear manufacturing company with characteristics of a flow shop machine environment, which minimizes ...
Analysis of folic acid in white rice by ultra-fast liquid chromatography

Parra LLanos, John Wilmer; RodrÍguez Ordoñez, Dora Cecilia; Torres Herrera, Laura Natalia (Journal of Physics: Conference SeriesReino Unido, 2019-11-19)

The method of analysis was standardized, and the folic acid content was determined in samples of fortified white rice (Z, G and D) and unfortified (E and O). The analysis was performed in triplicate in samples of 2.0000 ...
Effect of the number of layers on surface topography of bismuth-titanium coatings

GARZÓN AGUDELO, PEDRO; Bautista-Ruiz, Jorge; Aperador Chaparro, William Arnulfo (Journal of Physics: Conference SeriesReino Unido, 2019-11-29)

The objective of this research is to perform a topographic characterization by atomic force microscopy of the surface of bismuth titanate (Bi/Ti) coatings varying the number of layers deposited on the substrates, considering ...
Análisis de las dimensiones del proceso de transferencia tecnológica como métrica para cuantificar su absorción en entornos organizacional

PALACIOS ALVARADO, WLAMYR; Medina Delgado, Byron; López Bustamante, Oriana Alexandra (Revista Colombiana De Tecnologías De AvanzadaColombia, 2020-04)

La transferencia tecnológica germina como un elemento diferenciador entre las organizaciones, como ventaja competitiva, con el propósito de identificar la tecnología que puede contribuir a la organización favorablemente ...
Defensa 4.0: internet de las cosas en sistemas de batalla (IoBT) en defensa naval

RIOLA RODRIGUEZ, JOSE MARIA; FAJARDO-TORO, CARLOS HERNAN; Reina, Javier; Mayorga Torres, Oscar; Garnica López, Miguel Andrés (Revista Ibérica de Sistemas e Tecnologias de InformaçãoPortugal, 2020-05)

La cuarta revolución industrial I-4.0 se basa en la digitalización de sus procesos productivos, logísticos y militares, entre otros, permitiendo la interacción entre sistemas físicos y digitales, y logrando el uso de ...
Consideraciones para un modelo de simulación de procesos aplicado en construcción naval: caso armada de Colombia

Díaz Reina, Javier; FAJARDO-TORO, CARLOS HERNAN; Mayorga Torres, Oscar; RIOLA RODRIGUEZ, JOSE MARIA; Garnica López, Miguel Andrés (Revista Ibérica de Sistemas e Tecnologias de InformaçãoPortugal, 2020-05)

La simulación de procesos es una herramienta que posibilita la toma de decisiones en una línea productiva, logística o de servicios, a partir de un modelo conceptual que desarrollado en un software presenta escenarios ...
Analysis of caffeine in energy drinks by ultra-fast liquid chromatography

RodrÍguez Ordoñez, Dora Cecilia; Parra LLanos, John Wilmer; Medina-Cárdenas, Yurley (Journal of Physics: Conference SeriesReino Unido, 2020-08-05)

The objective of this work was to standardize the method of analysis of caffeine and determine its content in three energy drinks (Vive 100, Peak and Red Bull) consumed in the Colombian market, which were selected based ...
Study of the piston secondary movement on the tribological performance of a single cylinder low-displacement diesel engine

Duarte Forero, Jorge; Valencia, Guillermo; PALACIOS ALVARADO, WLAMYR (LubricantsSuiza, 2020-10-30)

The present study aims to analyze the secondary movement of the piston considering the deformations present in the piston skirt, the hydrodynamic lubrication, and the effects of the clearances in the connecting rod bearings. ...
Nanotechnological applications of polymer-drug conjugate as oncological treatment

PALACIOS ALVARADO, WLAMYR; Paipa Alvarez, Henry Omar; Medina Delgado, Byron (Journal of Physics: Conference SeriesColombia, 2020-11-04)

In recent years, the popular term "polymer-drug conjugate" has been introduced to describe new drug targets to combat diseases such as cancer. Due to its potential benefits in terms of human health, this concept has managed ...
Biodegradable thermosets polymers as an alternative solution to pollution generated by plastics

Paipa-Álvarez, H O; Palacios Alvarado, W; Medina Delgado, B (Journal of Physics: Conference SeriesColombia, 2020-11-04)

In this research work, a description was made of thermoset polymer materials and their relationship with the environment. The traditional thermoset manufacturing processes make their recycling and reuse complicated. ...
Evaluation of the mechanical behaviour to the force of tension between thermoplastic materials of origin and recycled

PALACIOS ALVARADO, WLAMYR; Medina Delgado, Byron; Durán Urón, Armando Engels (Journal of Physics: Conference SeriesColombia, 2020-11-05)

The use of plastic products and polymeric matrix compounds is increasing in engineering, most of these materials are subjected to dynamic loads, therefore, are constantly evaluated according to experimental methods that ...
Influence of COVID-19 confinement on physics learning in engineering and science students

Medina Delgado, Byron; PALACIOS ALVARADO, WLAMYR; mendoza lizcano, sonia maritza (Journal of Physics: Conference SeriesColombia, 2020-11-05)

Due to the global alert about the risk of contagion and propagation of Covid-19, a situation that has changed in the educational processes, this has forced the system to migrate towards a more dynamic and connected model ...
Contributing factors in academic performance and troubles associated with teaching in areas of physics in engineering students

GARZÓN AGUDELO, PEDRO; PALACIOS ALVARADO, WLAMYR; Medina Delgado, Byron (Journal of Physics: Conference SeriesColombia, 2020-12-16)

Learning processes are affected by a series of factors, both individual students and the institutional environment in which they develop. The present work is developed under the context of learning processes in areas of ...
Production sequencing in a flow shop system using optimization and heuristic algorithms

Caicedo-Rolón, Alvaro Jr; Parra LLanos, John Wilmer (Gestão & ProduçãoBrasil, 2021-03-31)

The purpose of the research was to determine the sequencing of the production of n jobs in m operations in a small footwear company in an environment of flow shop machine characteristics, which optimizes the total time of ...
Analysis of variables related to the mass flow of gaseous emissions in beehive ovens

mendoza lizcano, sonia maritza; Palacios Alvarado, W; Medina Delgado, Byron (Reino Unido, 2021-05-22)

In the combustion processes of the ceramic industry, large amounts of pollutant gas concentration are generated, so it is necessary to measure the system and the physical phenomenon, as well as the variables inherent to ...

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Production of bioethanol from rice husk pretreated with alkalis and hydrolyzed with acid cellulase at pilot scale
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Cacua Silva, Alejandra | 2018-12-07

Rice husk (RH) is the main biomass byproduct of the rice industry, so much that it corresponds to 20% of the total cereal production and is generally considered a waste. Due to its content of cellulose and hemicellulose, the RH has a great potential for its alternative use in the production of bioethanol, since it has a great advantage with respect to the conventional raw materials used (sugar cane, corn, beet and sweet sorghum, among others), given that this lignocellulosic material is abundant and does not compete with the food industry. The objective of this work was to obtain bioethanol from rice husk at a pilot scale, taking advantage of its cellulose and hemicellulose content. For this, a sample of 450g of RH was taken, which was pretreated with a 2.00% w/v NaOH solution and subsequently hydrolyzed with acid cellulase (CFB3S). The alcoholic fermentation of total reducing sugars (TRS) obtained in the enzymatic hydrolysis was carried out with Saccharomyces cerevisiae, finally, the fractional distillation of the must was carried out, by means of which four bioethanol samples were obtained with concentrations of 71.3% v/v, 30.0% v/v, 10.3% v/v, and 5.3% v/v of alcohol, which when mixed produced a sample of 95mL of solution with a concentration of 27% v/v alcohol (4.70g/100g of RH).

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Comparison of statistical forecasting techniques for Colombian coffee demand in South Korea
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PALACIOS ALVARADO, WLAMYR | 2019-03-06

This article shows a comparison of various methods as a statistical technique for making applied forecasts of Colombian coffee demand in South Korea. The aim is to model the demand behavior in the most adjusted and efficient way possible. To do this, the correlation factor between demand and different macroeconomic variables was analyzed, the one with the greatest relationship is selected and the autocorrelation factor is evaluated. Later, different deterministic methods are used such as linear regression by least squares, simple moving average, weighted moving average, simple exponential smoothing, and exponential smoothing with trend. As a result, a multiple linear regression analysis is obtained, an evaluation of the predictive capacity of the regression model was made through analysis of variance, and the calculation of the standard error of multiple estimation, multiple determination coefficient and the adjusted determination coefficient.

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La teoría de restricciones y la optimización como herramientas gerenciales para la programación de la producción. Una aplicación en la industria de muebles
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Romero Rojas, Julian David | 2019-07-18

La teoría de restricciones (TOC) es una filosofía de mejoramiento continuo, que se enfoca en el eslabón más débil de la cadena, para mejorar el desempeño del sistema productivo. El propósito de la investigación fue determinar la cantidades a fabricar de cada producto y su secuencia de producción en una industria mediana de muebles para cocinas y baños, a partir de los enfoques de la contabilidad del throughput de la TOC, y alternativamente la optimización, como la programación lineal. Se identificó como restricción (cuello de botella) del proceso productivo la etapa de mecanizado con una utilización del 193.71%, la cual se prevé mejore con la aplicación de la metodología de la TOC, incrementando las utilidades un 87.62 %. La contabilidad del throughput es una heurística apropiada, fácil de entender por parte de los gestores de la producción, y útil para soportar la toma de decisiones, aunque no siempre garantiza una solución óptima al problema de mezcla de producción. El procedimi ...

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Modelo matemático para la planeación de la producción en una industria metalmecánica
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Caicedo-Rolón, Alvaro Jr | 2019-09-30

La planeación de la producción es una decisión táctica a mediano plazo, que determina el nivel de trabajadores, inventarios y producción requeridos, para satisfacer la demanda en un horizonte de planeación. Se diseñó un modelo matemático para la planeación agregada de la producción en una industria metalmecánica mediana, donde se desarrolló una estrategia mixta que incluyó la persecución (contratación y despido) y nivel de inventarios, apartir de un modelo de programación lineal. Los resultados arrojaron las necesidades de cantidad de empleados, las contrataciones, los niveles de producción por jornada laboral y los inventarios, para cada proceso, que minimizanlos costos asociados al plan y satisfacen los requerimientos de la demanda. El modelo matemático diseñado y el proceso seguido para la planeación agregada de la producción, son una herramienta de apoyo a la toma de decisiones en la gestión de operaciones, ypuedenimplementarseen empresas de la industria metalmecánica.

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Evaluation of mechanical wear in bismuth-titanium coatings synthesized by the sol-gel method and applied on 316 L stainless steel substrates
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Aperador Chaparro, William Arnulfo | 2019-11

Steels are part of the basic equipment of most of the industrial framework, including very diverse sectors such as the oil, chemical and automotive industries. However, steels are susceptible to wear phenomena limiting their life in use and losing efficiency in the applications to which it is intended leading to a technological and economic problem. In mechanical systems, lubrication requires effective strategies to ensure that the increase in critical contact voltages does not cause material failure during operation. Although there are different ways to avoid the wear of steel parts, the development of material technology has allowed the manufacture of new alloys with anti-wear properties. Replacing steels with other higher cost materials is very unfeasible. For this reason, one of the alternatives of greatest interest to reduce wear is based on the surface modification of the metal through the use of coatings. The sol-gel method allows the manufacture of coatings on steel parts to reduce wear. The objective of this work was to manufacture, using sol-gel, bismuth-titanium coatings on 316 L stainless steel substrates in order to analyze the mechanical wear of the system and evaluate its wear rates and friction coefficients. The study focused on determining the effect of precursor concentration on performance as a film to reduce wear. It was determined that the friction coefficients show significant variations due to adhesive wear processes. With respect to wear, it is concluded that the coatings offer substrate protection by indicating wear rates lower than those reported for 316 L stainless steel substrates without coating.

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Mathematical model for production sequencing in a manufacturing company
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Parra LLanos, John Wilmer | 2019-11-19

The objective of the research was to determine the optimal sequence of production of n jobs in m operations, in a small footwear manufacturing company with characteristics of a flow shop machine environment, which minimizes the total time of completion of jobs in the production system, makespan. A mathematical model of integer linear programming was designed, coded and solved by means of the JuliaPro software. It shows the production sequence that does not consider permutation, and minimizes makespan with 3807 minutes. The mathematical model of optimization is presented as a flexible and valuable tool for operational decision making, which could be replicated in other manufacturing companies, impacting on the improvement of costs and delivery times.

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Analysis of folic acid in white rice by ultra-fast liquid chromatography
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Parra LLanos, John Wilmer | 2019-11-19

The method of analysis was standardized, and the folic acid content was determined in samples of fortified white rice (Z, G and D) and unfortified (E and O). The analysis was performed in triplicate in samples of 2.0000 g, hydrolysis was performed with phosphate buffer pH 8.82 for one hour and then lowered to pH 7.00 for enzymatic treatment with takadiastase at 65°C. The extracts were filtered by gravity, purified with nylon syringe filters and ion exchange cartridges (solid phase extraction using strong anion exchange cartridges). The concentration in mg folic acid/kg of rice, in each extract was determined by ultrafast liquid chromatography, with average values for Lot1 of the fortified rice samples, of 44.03, 51.95, 38.08, and unfortified samples of 31.51 and 21.94, and with respect to Lot2 of 41.26, 41.27, 34.54 for fortified ones and 24.92 and 20.94 for non-fortified ones, respectively. The concentration of folic acid obtained by filtration through syringe filters was higher than in the extracts purified by solid phase extraction using strong anion exchange cartridges, evidencing loss of the analyte. The recovery of folic acid in the samples doped and purified by syringe filters was around 65.00%, while by solid phase extraction using strong anion exchange cartridges 43.00%. There is evidence of variation in the folic acid content between different batches of rice of the same brand.

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Effect of the number of layers on surface topography of bismuth-titanium coatings
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GARZÓN AGUDELO, PEDRO | 2019-11-29

The objective of this research is to perform a topographic characterization by atomic force microscopy of the surface of bismuth titanate (Bi/Ti) coatings varying the number of layers deposited on the substrates, considering that there were not results of reported studies in which these precursors were used. It is important to analyze the surface behavior of these coatings as a first phase of future researches to establish the viability of possible uses and applications in biomedical industry. The films were synthesized by the sol-gel method from bismuth nitrate pentahydrate and titanium tetrabutoxide. Subsequently, by means of the spin- coating technique, the coatings were deposited on 316L stainless steel in monolayer and bi- layer, as this type of steel has been widely used for medical applications due to its good compatibility. The roughness values of each of the coatings were also determined. It is concluded that there is a relationship between the topography of the surface and the roughness values of the films with respect to the concentration of the precursors, the number and the speed of centrifugation of the layers deposited on the substrate. High concentrations of titanium tetrabutoxide effect on the good densification characteristics of the coatings.

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Análisis de las dimensiones del proceso de transferencia tecnológica como métrica para cuantificar su absorción en entornos organizacional
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PALACIOS ALVARADO, WLAMYR | 2020-04

La transferencia tecnológica germina como un elemento diferenciador entre las organizaciones, como ventaja competitiva, con el propósito de identificar la tecnología que puede contribuir a la organización favorablemente en su entorno dinámico, a partir de conocimientos tecnocientíficos, para implementar un desarrollo industrializado. Para ello, se empleó un muestreo simple aleatorio de una población determinada, se calcularon medidas de tendencia central y dispersión, a la vez se diseñó un instrumento de investigación que fue validado, a través de pruebas no paramétricas y se estableció su confiabilidad, este documento se diseñó a partir de la sistematización de variables. Los resultados indicaron que en cuanto a transferencia tecnológica, las empresas reconocen la tecnología de manera regular, lo que implica una concepción regular del ciclo de vida de la tecnología, de las fuentes para identificar la tecnología, y una concepción buena del mercado de la tecnología.

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Defensa 4.0: internet de las cosas en sistemas de batalla (IoBT) en defensa naval
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RIOLA RODRIGUEZ, JOSE MARIA | 2020-05

La cuarta revolución industrial I-4.0 se basa en la digitalización de sus procesos productivos, logísticos y militares, entre otros, permitiendo la interacción entre sistemas físicos y digitales, y logrando el uso de información en tiempo real para la toma de decisiones oportunas, así como la recolección de información para una planificación más precisa. En el campo militar, el empleo de Internet de las Cosas en el Campo de Batalla (IoBT Internet of Battlefield Things) ha permitido un acelerado desarrollo tecnológico en las operaciones militares, escenarios de batalla, procesamiento de datos y producción de equipos y maquinaria bélica, lo que en la literatura e industria militar se denomina Defensa 4.0. El presente artículo tiene como objetivo exponer la aplicación de la I-4.0 en el desarrollo, construcción y operación de los buques de guerra para el uso de la defensa naval, explicando su importancia e impactos en la industria militar.

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Consideraciones para un modelo de simulación de procesos aplicado en construcción naval: caso armada de Colombia
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Díaz Reina, Javier | 2020-05

La simulación de procesos es una herramienta que posibilita la toma de decisiones en una línea productiva, logística o de servicios, a partir de un modelo conceptual que desarrollado en un software presenta escenarios donde se mejoran las condiciones, restricciones o variables para intervenir en el proceso real. El presente artículo aborda las consideraciones de lógica, características, alcance, restricciones y variables de un modelo de simulación específico para la construcción naval de buques tipo OPV1 en la Armada de Colombia, con el objetivo de hacer mejoras, combinaciones, eliminaciones o ampliaciones de las capacidades disponibles del proceso actual, que permita estimar construcción naval futura y, en especial, buques de guerra (combatant ships2 ) de mayor tamaño.

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Analysis of caffeine in energy drinks by ultra-fast liquid chromatography
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RodrÍguez Ordoñez, Dora Cecilia | 2020-08-05

The objective of this work was to standardize the method of analysis of caffeine and determine its content in three energy drinks (Vive 100, Peak and Red Bull) consumed in the Colombian market, which were selected based on the results of a significant survey conducted to 384 people in the metropolitan area of "San José de Cúcuta, Colombia", from each energy drink two production lots were taken and in turn from each lot three drinks were taken for a total of 18, each one was analyzed in triplicate; caffeine concentration was determined on a Shimadzu Prominence ultra-fast liquid chromatograph. The average concentrations in mg of caffeine/L, for lot 1 were 256.96, 218.10 and 235.73 for drinks Vive 100, Peak and Red Bull, respectively and for lot 2, the respective values were 229.30, 233.86 and 238.33. As established in Resolution 4150 of 2009, the maximum limit allowed is 320 mg of caffeine/L, it was observed that the concentrations in all the energy drinks analyzed are lower, therefore, they are complying with the provisions of the law.

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Study of the piston secondary movement on the tribological performance of a single cylinder low-displacement diesel engine
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Duarte Forero, Jorge | 2020-10-30

The present study aims to analyze the secondary movement of the piston considering the deformations present in the piston skirt, the hydrodynamic lubrication, and the effects of the clearances in the connecting rod bearings. The analysis of the piston movement is performed by developing a mathematical model, which was used to evaluate the dynamic characteristics of the piston movement, the slap force on the piston skirt, the effect of the secondary piston movement on the connecting rod, and the influence of clearances in the connecting rod bearings and in the piston. For the study, the geometric of the crankshaft-connecting rod–piston system of a single-cylinder diesel engine is taken as a reference. The deformation model of the piston was carried out by means of a symmetric finite element model (FEM), which was integrated into the mathematical model of the piston. MATLAB® software (The MathWorks Inc., Natick, MA, USA) is used for the development of model simulations. The obtained results show that during the combustion cycle, there are six changes of direction in the secondary movement of the piston with lateral and angular velocities that can reach a magnitude of 0.13 m/s and 4 rad/s. The lateral and angular movement of the piston during its travel causes the appearance of impacts on the piston skirt with the cylinder liner, which produces an increase of approximately 500 N in the hydrodynamic forces in the connecting rod bearings. The force analysis shows that the range of the maximum magnitudes of these forces is between 1900 N and 3480 N. The increase in clearance between the cylinder liner and the piston skirt (Cpc) causes a greater lateral displacement and an increase in the angle of inclination of the piston. Analysis of the change in connecting rod bearing clearance shows that there are critical values in relation to clearance Cpc. The model presented allows us to analyze the different characteristics of the secondary movement of the piston, which involve the interaction between the piston skirt and the cylinder liner. Additionally, the influence of this movement on the connecting rod bearings is considered. The foregoing can be used as an analysis tool for the study of designs and/or modifications in the engine in such a way that greater durability of the components, reductions in acoustic emissions, and reduction in friction losses are achieved. View Full-Text

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Nanotechnological applications of polymer-drug conjugate as oncological treatment
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PALACIOS ALVARADO, WLAMYR | 2020-11-04

In recent years, the popular term "polymer-drug conjugate" has been introduced to describe new drug targets to combat diseases such as cancer. Due to its potential benefits in terms of human health, this concept has managed to gain attention in the pharmaceutical industry. These innovative developments involve detailed processes in materials science, as it is required to encapsulate different types of cells, as an active component within a material that releases the drug or conjugate directly on the tumor or in the affected area. Against this backdrop, the main objective of this work is to explore the state of participation of polymeric materials in medical and pharmaceutical sciences, in a context where recent cancer statistics are provided in some countries. From the review of the literature, it is evident the importance of the synthesis of new materials or polymeric conjugates, because these materials at the beginning have been used only as storage and delivery systems of drugs, but today they are used as direct treatment against diseases such as cancer, that is, as bioactive agents. Finally, it is possible to conclude that the conjugated polymer-proteins or polymer-drugs, currently on the market and others in the clinical research phase, these materials present physical properties such as biocompatibility and biodegradability, that is, compatibility with the living organism.

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Biodegradable thermosets polymers as an alternative solution to pollution generated by plastics
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Paipa-Álvarez, H O | 2020-11-04

In this research work, a description was made of thermoset polymer materials and their relationship with the environment. The traditional thermoset manufacturing processes make their recycling and reuse complicated. Consequently, most products made with this type of material end up accumulating in landfills and their disposal generates a high environmental impact. This is why a description of thermoset and biodegradable polymers is made to identify the differences between them and the advantages of biodegradable materials. This being so, it is found that the scientific community presents as a proposal or alternative solution to this environmental problem the development of new methodologies and technologies to synthesize families of thermoset biodegradable materials, as for example the case of "glycix", "titan" and "hydro", and that from capital investment in science and technology processes in the area of materials engineering, by the productive sector and Universities of countries such as for example; Mexico and Argentina, managed to develop on an industrial scale biodegradable resins that can be processed by all conventional plastic molding methods and significantly reduce the carbon footprint.

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Evaluation of the mechanical behaviour to the force of tension between thermoplastic materials of origin and recycled
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PALACIOS ALVARADO, WLAMYR | 2020-11-05

The use of plastic products and polymeric matrix compounds is increasing in engineering, most of these materials are subjected to dynamic loads, therefore, are constantly evaluated according to experimental methods that allow a characterization of their main properties. Therefore, this research work consisted in carrying out the characterization of mechanical properties of thermoplastic materials of different origin; commercial and recycled, where three cases were worked: Polymethylmethacrylate, polyvinyl chloride and polypropylene, for which there were 3.5 ± 0.1 mm thick sheets, manufactured by extrusion and supplied by a local supplier, in the city of San José de Cúcuta, Colombia. Afterwards, the specimens or samples were cut for the tension test adapting the shape and geometry, according to the standard test method for tensile properties of plastics, ASTM D638-14, using laser cutting for such purpose, the specimens were conditioned at a temperature of 20 °C during 40 hours prior to the moment of the tension test, the equipment used was a universal machine branded from Electro Mechanical Instrument & Components Corp., commercial reference DL2000 N° 11760 NS 784 with a speed adjustment of 5 mm/min to keep within the times given by the standard. Once the tests are performed, the stress/strain graphs of each case studied are obtained and the experimental results are analyzed from the data provided by the software "Tesc versão 4.00". Afterwards, Young's module is statistically analyzed and compared in each study, seeing which one presents the best behavior under the studied load conditions, raising a hypothesis, where the question is if the differences in the sample between Young's module can come from a population with an mean of zero, in this case, it is concluded that there is no difference between Young's modulus values for polymethylmethacrylate samples, the same occurred for polyvinyl chloride and polypropylene.

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Influence of COVID-19 confinement on physics learning in engineering and science students
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Medina Delgado, Byron | 2020-11-05

Due to the global alert about the risk of contagion and propagation of Covid-19, a situation that has changed in the educational processes, this has forced the system to migrate towards a more dynamic and connected model of teaching and learning, which has allowed not to interrupt and to continue with the training processes, in a remote and assisted way. In this research, the profile of the engineering and science student is analyzed, and its relationship with the learning of physics in this crisis. For this purpose, the technique of simple random sampling of a certain population was applied, a research instrument was designed and validated by pairs of experts, its reliability was established based on Cronbach's Alpha test, and the instrument was applied to 354 students of the faculty of engineering and basic sciences, of the Universidad Francisco de Paula Santander, located in the city of Cúcuta, Colombia, during a 15-day time window, the analysis of the data and variables is carried out from the design of a mathematical model of logistic regression, where the dependent variable represents the feeling of emotional affect by the obligatory social isolation. The results indicated that the students feel emotionally affected in 88.56% generating implications in the learning of physics and in their academic performance, especially those who comply the profile: being female, single, not having received training in the use of digital platforms, without academic difficulties but who feel that their academic performance has been affected.

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Contributing factors in academic performance and troubles associated with teaching in areas of physics in engineering students
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GARZÓN AGUDELO, PEDRO | 2020-12-16

Learning processes are affected by a series of factors, both individual students and the institutional environment in which they develop. The present work is developed under the context of learning processes in areas of physics in engineering students, belonging to the academic program of technology in industrial processes, considering the socio-demographic and academic variables that affect students and that in turn affect student dropout. Data collection instruments were applied to a population group of 90 students, allowing to propose strategic scenarios that would contribute to improve the quality of academic processes and students' skills in the study of mechanical and electromagnetic physics. It was determined that the role played by teachers and the methodology in which they teach their students, the physical conditions and teaching methods directly affect the effectiveness of learning and academic performance. It was also demonstrated that the lack of prior knowledge in the fundamentals of logic-mathematics and basic physics are determining aspects in the failure and repetition of the subjects.

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Production sequencing in a flow shop system using optimization and heuristic algorithms
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Caicedo-Rolón, Alvaro Jr | 2021-03-31

The purpose of the research was to determine the sequencing of the production of n jobs in m operations in a small footwear company in an environment of flow shop machine characteristics, which optimizes the total time of completion of the job in the production system (Makespan). We used heuristic algorithms that were applied through Lekin and WinQSB softwares, and for the optimization algorithm we designed a mathematical model that was solved by Juliabox software. Results show that the integer linear programming and local search minimize the makespan with 3807 minutes, and different production sequences for each algorithm, which consider permutation, which improves the traditional way of programming the production in 97 minutes, however, the optimization presents better results in the performance measures of average waiting time, average time of flow, and average job in process. Application of heuristic algorithms proves to be simple and fast, but the mathematical model of optimization designed and encoded in the software is a flexible and valuable tool for decision making in production programming, which could be applied in other footwear companies, and in other productive sectors whose companies have the same characteristics of the case study, reducing costs and improving delivery times.

LEER
Analysis of variables related to the mass flow of gaseous emissions in beehive ovens
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mendoza lizcano, sonia maritza | 2021-05-22

In the combustion processes of the ceramic industry, large amounts of pollutant gas concentration are generated, so it is necessary to measure the system and the physical phenomenon, as well as the variables inherent to the process, for subsequent estimation in terms of physical magnitudes, and a dimensional analysis, this allows to generate approximations in the causal relationships of the variables. The objective of the research is to analyze the behavior of the variables involved in the process and the influence of the mass flows of polluting gases. An exploratory and experimental methodology was used, for this, the data were taken with the technique of direct measurement in the sources of gas emissions and subsequently subjected to simulation in software such as AMOS V24.0 and LISREL V8.8., on the other hand, the data were subjected to an exploratory and confirmatory factorial analysis, using SPSS software version 24.0. As a result, the variables capacity and production are practically identical, which leads to a high correlation and, consequently, an undesired multicollinearity between the variables, so the suggestion is to omit one of them. On the other hand, the sulfur percentage variable is inversely correlated with most of the variables and its saturation is not clear, so it is theoretically sustained as a latent variable of the SO2 indicator.

LEER