Análisis de velocidad de soldadura robotizada para proceso MIG en acero1045 AISI

Carlos Eduardo Hernández Acero (2022, [Tesis de maestría])

Esta investigación denominada “análisis de velocidad de soldadura robotizada para proceso MIG en acero 1045 AISI” busca el desarrollo de un modelo matemático que permita, mediante parámetros conocidos, el cálculo de la penetración de soldadura en piezas unidas con proceso Metal Inert Gas (MIG). El objetivo se centra en buscar la combinación de valores paramétricos para la velocidad de soldadura, el voltaje y la corriente, los que se obtienen mediante la aplicación de un diseño experimental, que, ejecutadas en el proceso, pueda lograr una penetración de soldadura aceptable para la unión de la pieza. El modelo de superficie de respuesta aplicado fue un diseño de experimentos 2k con diseño central compuesto, y posteriormente el modelo se utilizó para estimar la velocidad de soldadura. Este diseño de experimentos se ejecutó por medio del programa estadístico Minitab versión 17. (Hernández Acero et al., 2022). Una vez teniendo la penetración de soldadura deseada en la pieza, se puede calcular la velocidad de soldadura necesaria para el cálculo de tiempo ciclo y utilizar los parámetros definidos de corriente y voltaje. Los valores de estos factores serán útiles para comenzar la programación del robot ya con la celda funcional y reducir el tiempo de arranque en automático (Hernández Acero et al., 2022).

This research, named “robotic welding speed analysis for MIG process in 1045 AISI steel”, seeks to develop a mathematical model that allow, through know parameters, the calculation of welding penetration in parts joined with Metal Inert Gas (MIG) process. The objective is focused on finding the combination of parametric values for robot welding speed, voltage and current, which are obtained through the application of a design of experiments, which, executed in the process, can achieve an acceptable welding penetration for the union of the part. The response surface model applied was a 2k design of experiments with central composite design, and subsequently the model was used to estimate the welding speed. This design of experiments was obtained using the statistical software Minitab version 17. (Hernández Acero et al., 2022). Once having the desired welding penetration in the part, it can calculate the welding speed necessary for the cycle time calculation and use the defined parameters of current and voltage to start programming the robot with the functional cell and reduce the time of startup (Hernández Acero et al., 2022).

Soldadura MIG Penetración Tiempo ciclo Velocidad de soldadura MIG welding Penetration Cycle time Welding speed INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS

Planting rice at monsoon onset could mitigate the impact of temperature stress on rice–wheat systems of Bihar, India

Carlo Montes Anton Urfels Eunjin Han Balwinder-Singh (2023, [Artículo])

Rainy Season TIMESAT APSIM Agricultural Production Systems Simulator Climate Adaptation CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA RICE WHEAT MONSOONS WET SEASON CROP MODELLING CLIMATE CHANGE ADAPTATION

Remedies for the Inconsistences in the Times of Execution of the Unsorted Database Search Algorithm within the Wave Approach

Manuel Ávila Aoki José Benito Elizalde Salas (2017, [Artículo])

The typical semiclassical wave version of the unsorted database search algorithm based on a system of coupled simple harmonic oscillators does not consider an important ingredient of Grovers original algorithm as it is quantum entanglement. The role of entanglement in the wave version of the unsorted database search algorithm is explored and contradictions with the time of execution of Grovers algorithm are found. We remedy the contradictions by employing two arguments, one of them qualitative and the other quantitative. For the qualitative argument we employ the probabilistic nature of a legitimate quantum algorithm and remedy the above inconsistence. Within the quantitative argument we identify a parameter in the wave version of the unsorted database search algorithm which is related to entanglement. The contradiction with the time of execution of Grovers algorithm is solved by choosing an appropriate values of such a parameter which incorporates entanglement to the wave version of the unsorted database search algorithm. The utility of the present arguments are evident if the wave version of the unsorted data base search algorithm is experimentally implemented through a system of N quantum dots with a harmonic oscillator potential as a confinement potential for each of the quantum dots. Each of the above N vibrating quantum dots must be coupled to an extra single vibrating quantum dot which entangles to all of them. In order to obtain optimal results, the coupling constants of the mentioned quantum dots should be adjusted in the way described in the present work.

Computación Unsorted database search Grover algorithm wave entanglement queries time Computación Unsorted database search Grover algorithm wave entanglement queries time INGENIERÍA Y TECNOLOGÍA

The past, the present, the future, and occupational self-efficacy: an attributions and cultural differences perspective

Daniel Arturo Cernas Ortiz (2023, [Artículo, Artículo])

This study´s objective was to examine empirical relationships between three dimensions of time perspective (future, present fatalistic, and past negative) and occupational self-efficacy. By surveying Mexican (n = 286) and U.S. (n = 272) respondents, we also tested the moderating role of culture. Regression analyses revealed that time perspective dimensions have significant associations with occupational self-efficacy, being future time perspective more potent than its past negative and present fatalistic counterparts. Moderation analyses indicated that none of the examined time perspective-self-efficacy relationships varied significantly between the U.S. and Mexico. Overall, this study suggests that relationships between time perspective and occupational self-efficacy vary according to different temporal dimensions, that future TP is key to develop occupational self-efficacy, and that cultural values may not exert a significant influence on the time perspective-occupational self-efficacy connection.

Perspectiva de tiempo autoeficacia diferencias culturales análisis de moderación CIENCIAS SOCIALES CIENCIAS SOCIALES Time perspective self-efficacy cultural differences moderation analysis

Implementación de la metodología Lean Sigma en un proceso de ensamble de engranes y cadenas: Caso de estudio

Omar Celis Juan Alfonso Toscano Moctezuma (2022, [Artículo, Artículo])

RESUMEN

La metodología orientada a solución de problemas propuesta en este artículo de investigación tiene como objetivo actuar a la velocidad de Lean brindando resultados en al menos cuatro semanas. Las cinco fases de esta metodología son: identificar y medir el problema; encontrar las posibles causas que están generándolo; desarrollar una solución empleando herramientas de Lean o de Seis Sigma; una vez implementada la solución, verificarla con una corrida de comprobación y, finalmente, desarrollar un plan de control para asegurar que el estado alcanzado se mantenga en el mediano y largo plazos. Para comprobar la efectividad de la metodología Lean Sigma, se presenta un caso de aplicación en un proceso que no cumple con los requerimientos de entrega a tiempo. Por medio de herramientas Lean, como rebalanceo de la línea, takt time y just in time, se logró incrementar el porcentaje de entregas a tiempo de un 66 % a un 100 % y, a su vez, la productividad aumentó de 1.8 a 2.5 piezas/min*hombre y el lead time disminuyó de 26.07 a 17 segundos, equivalente a una mejora del 35 %. El problema fue resuelto en 24 días y la capacidad del proceso fue de un 2.6 a 3.4 sigma.

Lean Sigma Takt Time Lean Seis Sigma Solución de Problemas CIENCIAS SOCIALES; INGENIERÍA Y TECNOLOGÍA CIENCIAS SOCIALES INGENIERÍA Y TECNOLOGÍA

A comprehensive account of SARS-CoV-2 genome structure, incurred mutations, lineages and COVID-19 vaccination program

Shailendra Sharma deepmala sehgal Apekshita Singh Shailendra Goel SoomNath Raina (2022, [Artículo])

Corona Viruses Genome Structure Novel Mutations Resistance to Vaccines SARS-CoV-2 CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA COVID-19 ANTIBODY FORMATION LIFE CYCLE VACCINATION VACCINES LINEAGE

Advancing the science and practice of ecological nutrient management for smallholder farmers

Sieglinde Snapp (2022, [Artículo])

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AGROECOLOGY DEGRADATION NUTRIENT CYCLES NUTRIENT USE EFFICIENCY SOIL ORGANIC MATTER SMALLHOLDERS

The fate of rice crop residues and context-dependent greenhouse gas emissions: Model-based insights from Eastern India

Sonam Sherpa virender kumar Andrew Mcdonald (2024, [Artículo])

Crop residue burning is a common practice in many parts of the world that causes air pollution and greenhouse gas (GHG) emissions. Regenerative practices that return residues to the soil offer a ‘no burn’ pathway for addressing air pollution while building soil organic carbon (SOC). Nevertheless, GHG emissions in rice-based agricultural systems are complex and difficult to anticipate, particularly in production contexts with highly variable hydrologic conditions. Here we predict long-term net GHG fluxes for four rice residue management strategies in the context of rice-wheat cropping systems in Eastern India: burning, soil incorporation, livestock fodder, and biochar. Estimations were based on a combination of Tier 1, 2, and 3 modelling approaches, including 100-year DNDC simulations across three representative soil hydrologic categories (i.e., dry, median, and wet). Overall, residue burning resulted in total direct GHG fluxes of 2.5, 6.1, and 8.7 Mg CO2-e in the dry, median, and wet hydrologic categories, respectively. Relative to emissions from burning (positive values indicate an increase) for the same dry to wet hydrologic categories, soil incorporation resulted in a −0.2, 1.8, or 3.1 Mg CO2-e change in emissions whereas use of residues for livestock fodder increased emissions by 2.0, 2.1, or 2.3 Mg CO2-e. Biochar reduced emissions relative to burning by 2.9 Mg CO2-e in all hydrologic categories. This study showed that the production environment has a controlling effect on methane and, therefore, net GHG balance. For example, wetter sites had 2.8–4.0 times greater CH4 emissions, on average, than dry sites when rice residues were returned to the soil. To effectively mitigate burning without undermining climate change mitigation goals, our results suggest that geographically-target approaches should be used in the rice-based systems of Eastern India to incentivize the adoption of regenerative ‘no burn’ residue management practices.

Soil Carbon Rice Residue Burning Life Cycle Assessment CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SOIL CARBON RICE LIFE CYCLE GREENHOUSE GASES CLIMATE CHANGE

Character association study in maize hybrids developed through integration of rapid cycle genomic selection and doubled haploid technology for heat stress tolerance

Prakash Kuchanur Ayyanagouda Patil Pervez Zaidi vinayan mt (2023, [Artículo])

Multi-Parental Synthetics Rapid Cycle Genomic Selection Phenotypic Correlation CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA MAIZE HEAT STRESS MARKER-ASSISTED SELECTION DOUBLED HAPLOIDS PHENOTYPIC VARIATION CLIMATE CHANGE

Metodología Value Stream Mapping (VSM) aplicada a procesos de perforación de pozos petroleros en México

Value Stream Mapping (VSM) methodology applied to oil well drilling processes in Mexico

NEMIAS VASQUES MORALES CARLOS BELISARIO CASTAÑEDA CASTAÑEDA (2023, [Artículo])

Con los cambios recientes en el sector energético a nivel mundial, la industria petrolera enfrenta retos importantes en la extracción de hidrocarburos, por lo que se ha priorizado la implementación de operaciones que permitan esta actividad de forma eficiente y optimizada. En este trabajo se analizará la aplicación de una de las herramientas del Lean Manufacturing, el VSM (Value Stream Mapping) con la finalidad de identificar posibles mejoras y disminución de tiempos no productivos en los procesos de perforación de pozos petroleros, de acuerdo a las experiencias previas en campos desarrollados en México. Se pretende demostrar que herramientas de análisis de eficiencia para la manufactura pueden adaptarse a industrias pesadas como la petrolera y en particular del área de perforación.

With recent changes in the energy sector worldwide, the oil industry faces significant challenges in the extraction of hydrocarbons, which is why the implementation of operations that allow this activity in an efficient and optimized manner has been prioritized. In this work, the application of one of the Lean Manufacturing tools, VSM (Value Stream Mapping) will be analyzed with the purpose of identifying possible improvements and reduction of non-productive times in the oil well drilling processes, according to experiences. previous ones in developed fields in Mexico. The aim is to demonstrate that efficiency analysis tools for manufacturing can be adapted to heavy industries such as the oil industry and in particular the drilling area.

Lean Operaciones Tiempos no productivos Operations Non-productive times INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS