ISSN / EISSN : 0012-7361 / 1989-1490
Published by: Publicaciones DYNA (10.6036)
Total articles ≅ 1,391
Latest articles in this journal
DYNA, Volume 97, pp 344-344; https://doi.org/10.6036/10419
El modelo de asignación de costes de Varela-Laso et al.  fue aplicado en una facultad de una Universidad pública chilena. El modelo propuesto es una adaptación al sistema de costeo basado en actividades (ABC) presentado por Kaplan y Cooper  que considera en una primera etapa la identificación de objetos de costes intermedios, correspondientes a los diversos resultados de la gestión universitaria: docencia de pregrado, docencia de postgrado, investigación, administración académica, perfeccionamiento, entre otros.
DYNA, Volume 97, pp 345-345; https://doi.org/10.6036/10498
This work designs a stochastic model of an evaporator of a refrigeration system, subject to specific conditions, applying the Risk-Sensitive (R-S) stochastic control equations with tracking, to control the evaporator temperature achieving great energy savings, where the actuator is the expansion valve (EEV).
DYNA, Volume 97, pp 374-379; https://doi.org/10.6036/10494
Electric vehicles with cleaner, cheaper, and more efficient powertrain technologies are being developed by the automotive industry to reduce emissions and make cities more liveable. This imposes weight and size restrictions on the electric powertrain to lower the energy consumption, to leave enough room for the batteries, and to minimize the unsprung mass, in the case of vehicles driven by in-wheel electric motors. This paper presents the design of gear reducer for in-wheel electric motor as small and light as possible.
DYNA, Volume 97, pp 359-363; https://doi.org/10.6036/10477
AEmissions and noise from transport affect seriously people's health and environmental ecosystems, requiring the implementation of monitoring and mitigation measures to achieve a real reduction in all transport modes and achieve a real sustainable mobility. Monitoring systems integrated in the infrastructure can help in identifying vehicles that do not respect certain emission limits. In this scenario, NEMO project (Noise and Emissions Monitoring and radical mitigation) seeks to create the most advanced and purely European solution to reduce emissions and noise from transport, by empirically measuring individual vehicles to apply personalized tariffs to the most emitting vehicles or preventing their access to sensitive zones. The whole NEMO concept is focused on the development (hardware, infrastructure and software) of a reliable novel Remote Sensing systems to measure traffic emissions and noise. The system is integrated into existing road, rail, maritime and IT infrastructures to make it standardized, more user-friendly and able to operate continuously without human supervision for continuous monitoring. The new measurement systems, present a wider measurement range to ensure that the sensitivity of the measurements is adequate to the development of the automotive industry, thus helping to form a global and scalable solution to improve air quality and reduce noise impact in European cities.
DYNA, Volume 97, pp 410-417; https://doi.org/10.6036/10340
GJS 400-15 ductile cast iron has excellent physical-chemical, mechanical-structural and manufacturability properties. However, it has notable limitations when it is subjected to the welding operations to which it is subjected. The objective of this work is the characterization of the welds made in GJS 400-15 ductile cast iron parts, specifically 6mm thick sheets, to determine their applicability based on the mechanical and microstructural properties obtained. For this, several welding procedures have been proposed, in which an Fe-Ni alloy is used as a filler material and SMAW and TIG welding techniques are combined with different heat treatments. The mechanical characterization tests have been based on tensile analysis and hardness determination. As for the micrographic analysis, it has been carried out through the micrographs of the thermally affected areas (base metal, interface and welding. TIG welding, in general terms, has been effectively effective in the welding processes of nodular cast iron sheets despite its disadvantage in the results obtained compared to the SMAW technique. On the contrary, the advantages that the TIG welding technique presents in terms of execution time and more favorable cost open a way to the development, technical evolution and industrialization of the welding processes carried out using this last technique. It is hoped that the study will present a positive contribution to the technological development of welding processes and their industrial application to the manufacture, maintenance or repair of parts and products in which ductile iron is present and especially those formed by steel plates. small thickness. Keywords: ductile cast irons welding, SMAW, TIG, heat treatments, preheating, annealing, traction, hardness, micrograph
DYNA, Volume 97, pp 436-444; https://doi.org/10.6036/10398
In recent years, policy makers have paid more attention to cycling when considering sustainable mobility plans. Understanding the spatio-temporal patterns of cycling mobility can serve as a reference for planning cycling infrastructures. This study explores the application of the Getis-ord Gi* statistic, spreading the values of counter stations by spatial interpolation methods to analyse the geographical effects of the winter season for cycling mobility in Valencia (Spain). From 447,845 measures collected by 59 loop detectors, the variability in the number of bicycles on working days and on weekends in terms of consecutive, dismissing, intensifying, persistent, oscillating, sporadic, or new hot/cold spots was analysed with a time variation of 30 minutes. In contrast to what would be expected, the winter season does not have a significant influence on the use of bicycles around university campuses on weekdays or in recreational areas on weekends, defining these as hot spots. Instead, the Valencia surroundings present persistent and intensifying cold spots, being limited by subway stations during winter when changes occur in the means of transport. Persistent hot spots show accepted mobility patterns among the population of Valencia that could be promoted by the local government, e.g., by improving the availability of bicycles among students and designing attractive weekend rides for all citizens as a healthy activity. Keywords: Getis-Ord Gi*, Spatio-temporal analysis, spline interpolation with barriers, cycling activity
DYNA, Volume 97, pp 350-350; https://doi.org/10.6036/10502
Landslides constitute one of the biggest problems in the construction of slopes, which can be caused by various factors such as climatic changes, mechanical properties of the constituent soils, the increase in the inclination of the slope, the height of the slope, forces of seepage, earthquakes, gravitational forces and acting stress states. Some methods to prevent infiltration, erosion and reinforce the surface of the slope consist of covering the surface with synthetic materials, vegetation and modified soils, among others.
DYNA, Volume 97, pp 348-348; https://doi.org/10.6036/10481
Natural ventilation is one of the most suitable and sustainable means against COVID-19 in confined spaces, where social distancing reduces the possible cross transmission of the virus between humans.
DYNA, Volume 97, pp 368-373; https://doi.org/10.6036/10487
The digital transformation of the automobile industry linked with the new challenges of sustainable mobility, is generating important changes in the business models of automobile groups. The constant efforts to innovate in its vehicles and offer services associated with them are essential to guarantee its own sustainability. Automation, connectivity, electrification and shared mobility (ACES) are the four technological drivers of this sector and have been taken as a reference in this research to examine and learn how the main European automobile groups are addressing the global challenges associated with them. It is of special interest to offer this compilation of information that allows obtaining a current and well-founded vision of the advances in the sector, giving visibility to the commitment, effort and performance that these companies are carrying out. Likewise, the results obtained show different levels of integration and progress of the ACES factors in the automobile companies studied.
DYNA, Volume 97, pp 425-431; https://doi.org/10.6036/10520
The impact of temporary control measures on regional air quality during large-scale events is the focus of current research. Most of them focus on the discussion of environmental particulate matter concentration, while the changes in O3 concentration during such periods have not been explored. To reveal the variation characteristics of environmental O3 concentration during large-scale events, the ozone pollution control during the 2019 National Games in Zhengzhou, China was considered as an example and the six pollution parameters of state-controlled stations, meteorological parameters, and online volatile organic compound (VOC) component data was used. The evolution law of O3 pollution in Zhengzhou before and after the implementation of control measures was discussed, and the changes in NOx and the components of VOCs in different control stages were compared. The positive matrix factorization model was used to analyze the contribution of different types of pollution sources to the O3 mass concentration in Zhengzhou during the observation period. Results show that during the National Games, the concentration of O3 decreased by 45.2% and 29.3% compared with that before control and during Stage-I of control, respectively. The concentration of alkanes, olefins, and alkynes decreased significantly during the National Games, whereas the concentration of aromatic hydrocarbons increased by 6.5%. The pollution sources with the highest contribution of VOCs in Zhengzhou were as follows: motor vehicle tail gas source (the average contribution was 32.8%), natural gas/oil source (26.3%), solvent use source (20.4%), industrial process source (13.9%), and natural plant source (6.7%). The research conclusion revealed the evolution characteristics of O3 concentration and the causes of pollution during large-scale activities. Key Words: O3 pollution, VOCs, Control measures, the National Games, PMF source apportionment