Ciencias de la Ingeniería y Aplicadas

Moisture transport mechanism in stockpile subjected to wind and solar drying

Sun, 29 Jun 2025 00:34:21 +0000

In the Cuban nickel industry, wind and solar drying of laterites is implemented in an empirical way, which leads to inaccuracies in the estimation of moisture reduction achieved during the process. In this work, simulations of moisture distribution in piles of material exposed to natural drying were developed using models, algorithms and computer programs developed in previous works. The energy analysis showed that, on average, in the east and west slopes of the pile considered, moisture was reduced by 0.410 and 0.490 %, respectively. And in the complete pile the reduction was 0.450 % for a drying time of 12 hours, measured between 6 and 18 hours. The obtained behaviors suggest that during the natural drying process the moisture in the piles moves due to a mixed transport mechanism, which includes the combined effects of vapor diffusion, liquid diffusion and liquid movement

Kolmogorov-Smirnov test for two large samples with two-tailed samples

Sun, 29 Jun 2025 00:55:49 +0000

The problem investigated arose from the identification of persistent deficiencies in doctoral theses, master's degrees, and diploma theses related to hypothesis validation. The objective of this work was to show how to validate a hypothesis using the nonparametric Kolmogorov-Smirnov test for large, two-tailed samples. The master's thesis of the main author of this work was used as a reference, through which the criteria of 140 randomly selected teachers from the Technical and Vocational Education Department in the province of Holguín and 35 experts from across the country were validated. This made it possible to determine whether there was concordance in relation to the evaluations issued by these teachers, related to the dimensions and indicators for assessing the educational impact of the Industrial Polytechnic Schools of said province (proposed by the author). As a result, it was established, with 95% confidence, that the evaluative criteria for each indicator issued by the experts were consistent with the criteria expressed by the teachers of the Technical and Vocational Education Department in the province of Holguín, which made it possible to validate, with a greater degree of confidence, the relevance of the hypothesis posed in the thesis. It can be concluded that this work demonstrates in a practical way how to apply this valuable tool that enables the validation of research hypotheses

Modeling and tuning of the active power control loop in a power plant

Sun, 29 Jun 2025 01:17:48 +0000

The MAN engine generator set (a German internal combustion engine manufacturer) with a maximum rated power of 184 MW, located in the city of Moa, Holguín province, is one of the power plants connected to the SEN (National Electric Power System), contributing 165 MW to the system's demand. The generators' active power is regulated by the fuel input to the internal combustion engine, which rotates at a speed of 514 rpm, accelerating or decelerating. The control loop, tuned by trial and error, consists of current and voltage transformers, a PLC (Programmable Logic Controller), and an actuator to manipulate fuel flow. Over the years of operation, the company's engines have suffered wear in their fuel regulation mechanisms, resulting in power fluctuations and losses of up to 2 MW. This article proposes parametric models that describe the system dynamics. Passive experiments were conducted over 10 operational days to model the behavior of engine power relative to the position of the actuator that manipulates fuel flow. As a result, parameters for automatic controllers were proposed to optimize energy consumption, minimize friction losses or thermal inefficiencies, improve combustion efficiency, and reduce pollutant emissions

Improvements to the maintenance system for radio-electronic equipment in companies in northern Holguín

Sun, 29 Jun 2025 01:31:09 +0000

This paper focused on the analysis of the maintenance management of radio electronic equipment in companies in the northern Holguín region (ETNH). Changes were proposed that contributed to improved performance and outcomes. The Planned Preventive Maintenance system was applied, with acceptable results, but with significant room for improvement, which led to changes in the system. Several methods were used for all technological equipment to facilitate the acquisition of information that allowed for decision-making, but focused primarily on the systems and elements with the greatest impact on the occurrence of SWR (Standing Wave Ratio) failures, such as the antenna, low-pass filter, switching card, high-voltage source, and coaxial cable. This failure was the most significant, and allowed determining technical availability based on the mean time between failures, mean time to repair, maintenance and repair costs, and the actual operating conditions of the equipment. The main tools used are Criticality Analysis and Pareto. With the information available through the use of these tools, proposals for improvements were made based on the results obtained

Integration of Digital Technologies for Engineering Innovation

Wed, 02 Jul 2025 01:15:33 +0000

Technological and digital evolution is revolutionizing modern education by facilitating new opportunities to enhance learning processes. Many of these advances have had a measurable impact on educational environments, as evidenced by the increasing use of digital platforms, technological tools, and virtual learning environments. These elements support the development of new methodologies that foster active learning. Recent studies indicate that over 80% of educational institutions have incorporated technology into their teaching processes, improving academic performance and promoting skills such as critical thinking and digital literacy. However, challenges remain in terms of equitable access, as 30% of students lack adequate connectivity or devices. Therefore, the need for public policies that promote digital equity is emphasized.

Simulation and mathematical modeling of a 4-degree-of-freedom robotic ARM

Luis Armas, Jessica N Castillo, Luigi O Freire — Wed, 09 Jul 2025 16:40:11 +0000

The following article shows in detail the development of the modeling process of a manipulator of a robotic arm corresponding to four degrees of freedom (4GL) this study was based on direct kinematics for the calculation and accuracy of the position of the end effector based on their joint directions. It starts from a particular position and its location in the plane is observed. The use of the method was done because it is important to identify the movement of the robot. The simulation was performed using Matlab software, in this program it was possible to illustrate the movement of the robot and how it correctly reaches the movement in the direction of a previously defined trajectory. Additionally, a test was implemented that helped to verify that the robot was able to position itself at the desired end point and that the errors generated were minimal. The results showed that the control system reached a steady behavior, and that the tracking error was reduced to converge to zero, demonstrating an efficient and precise movement, which occurred in a time of approximately 8 seconds, which evidences an adequate stability and an effective design of the control system. The stability of the movement was also evaluated by applying the Lyapunov criterion, which provides a theoretical confirmation of the reliability of the control system used. In summary, the results show that the robotic arm is capable of performing complex trajectories while maintaining a stable motion.

Study of the Electric Power Generation System through the Analysis of Hydroelectric Plants to Highlight the Energy Deficit in Tungurahua Province

Verónica Gallo , Pamela Espejo, Santiago Alvarez, Jenny Nuñez — Wed, 09 Jul 2025 16:47:02 +0000

The project "Study of the Power Generation System through the Analysis of Hydroelectric Plants to Highlight the Energy Deficit in the Province of Tungurahua" evaluates the current hydroelectric generation capacity in the region, identifying limitations and proposing strategies to improve electricity supply. In response to growing demand and frequent blackouts affecting key sectors such as industry and agriculture, a mixed methodology was applied. This included the analysis of historical data from institutions such as EEASA, ARCONEL, CONELEC, and SNI, along with surveys and interviews with technicians and industry professionals. The results indicate that hydroelectric plants operate at 62% of their capacity, with an average deficit of 48 MW during peak hours. The main causes include lack of maintenance, reduced water flow, and outdated infrastructure. As a solution, the study proposes technological modernization, diversification of the energy matrix by incorporating solar sources, and the implementation of differentiated tariffs to optimize consumption. The study emphasizes the need for strategic investments and sustainable energy planning to reduce vulnerability to climate change and ensure regional economic development. Tools such as HEC-ResSim and PLEXOS were used to model hydroelectric generation scenarios and assess the integration of complementary renewable energy sources.

Impact Of The Oil Condition On The Thermography Of Turbocharger Operation

Wed, 09 Jul 2025 16:53:57 +0000

In The turbo of a diesel engine reaches very high temperatures during operation, so the role of the lubrication system and in particular the oil is fundamental for its care and performance. The project involves the use of thermography to determine the impact of oil quality on turbo operation, therefore, it is intended to investigate the thermal behavior of a turbocharger in its different work areas under certain operating conditions and how oil influences as a refrigerant in this supercharging system. The maintenance required by this type of elements are expensive, so care in its operation is fundamental, being the purpose of the project to establish the role of the lubricant in the care of the turbocharger, in addition to the incorporation of new tools in the processes of revision of the vehicle such as the thermal camera.

Analysis of Power Quality in Residential Homes in Ecuador: Impact of Home Automation on Harmonics and Voltage Fluctuations

Wed, 09 Jul 2025 20:56:56 +0000

This study evaluates the impact of smart home devices on energy efficiency and power quality in a residential dwelling in Pelileo, Ecuador. The research was conducted through a two-stage monitoring process using a smart meter and a Fluke 1735 power analyzer, both before and after the implementation of smart devices. Results indicate a 10.9% reduction in total energy consumption, highlighting economic potential. However, an increase in harmonic distortion led to a 3.4% reduction in power factor, raising concerns about energy quality degradation. The study underscores the importance of addressing power quality issues when implementing energy-saving technologies in residential settings.

Experimental and numerical validation of the modal analysis of a cantilever beam using LabVIEW and finite element simulation

Wed, 09 Jul 2025 21:30:09 +0000

This study presents a cross-validation between experimental modal analysis (EMA) and numerical simulation using the finite element method (FEM) on a cantilever beam. The physical testing involved a National Instruments CompactDAQ system and LabVIEW software, with impact excitation using an instrumented hammer and signal acquisition through piezoelectric accelerometers. The numerical model was built in SolidWorks and simulated using Autodesk Inventor Nastran and LISA. The comparison of natural frequencies revealed strong agreement between both approaches, with relative errors below 12% across the first five modes. The validated procedure, tested on a simple structure, demonstrates potential for extension to the dynamic analysis of more complex systems, such as mechanical components, buildings, or bridges.This approach offers a feasible and cost-effective alternative for structural validation in academic, industrial, and diagnostic applications

Effect of using different raw materials on quality parameters in eggs enriched with Omega-3

Sebastián Alejandro Cárdenas Bustos — Wed, 09 Jul 2025 21:36:41 +0000

The present investigation analyzed the quality parameters of eggs enriched with Omega-3, from different raw materials added to the diet of laying hens of the Lohman Brown line, in the poultry workshop of the Agricultural Career, located in the Hacienda El Prado, San Fernando parish, Sangolquí city, Rumiñahui canton, Pichincha province.

The variables analyzed were weight, albumen height, yolk coloration, Haugh Units, shell resistance and shell thickness, through the Digital Egg Tester DET6000 equipment.

For the project, a completely randomized experimental design was used, with three treatments and a control. Each treatment consisted of a different plant source of linolenic acid. The first treatment was a diet formulated with flaxseed, the second a diet formulated with chia, and the third a diet formulated from a mixture of flaxseed with canola oil. A Tukey test for comparison of means at 5% was used. Through the INFOSTAT software, each quality parameter was analyzed for the treatments and the control, resulting in the color of the yolk the only variable with significant differences for the diet formulated with canola oil and linseed as sources of linolenic acid.

Additionally, the organoleptic and sensory characteristics of each treatment and the control were analyzed by a total of ten tasters, who rated the smell, taste, texture and visual appearance of the Omega-3 enriched eggs and the control eggs.