Artículo
Permanent URI for this collectionhttps://hdl.handle.net/11285/345284
Artículo científico o editorial en una publicación periódica académica sujeto a revisión de pares. Cumple con los índices internacionales o bases de datos de amplia cobertura, como el listado del Current Contents, ISI WEB of Knowledge (http://isiknowledge.com/) e índice de revistas mexicanas de CONACYT (www.conacyt.mx/dac/revistas). Éstos indizan y resumen los artículos de revistas seleccionadas, en todas las áreas del saber.
Browse
Search Results
- Plasma transferred arc additive manufacturing of Nickel metal matrix composites(Elsevier, 2018-10-06) Mercado Rojas, J.G.; Wolfe, T.; Fleck, B.A.; Qureshi, Ahmed Jawad; University of Alberta; Instituto Tecnológico y de Estudios Superiores de Monterrey; Mears, LaineThis paper analyzes the geometric stability and microstructure characteristics of metal additive manufacturing parts using plasma transferred arc with Metal Matrix Composites. The technology used to enhance the capabilities of a plasma system to create an additive manufacturing system is described. Geometric stability, microstructure porosity and cross-sectional hardness analysis of the additive manufacturing parts are discussed. This work confirms that the new capabilities of the system allow building a 3D printed part of nickel-base metal matrix with tungsten carbide particles for wear resistance. The results will lead to the development of large-scale additive manufacturing parts for industrial purposes.
- In-service teachers’ self-perceptions of digital competence and OER use as determined by a xMOOC training course(Elsevier, 2017-09) Ramírez-Montoya, María-Soledad; Mena, Juanjo; Rodríguez-Arroyo, José A.; Tecnologico de Monterrey; Matthieu GuittonDigital Competence (DC) is considered a driver for educational innovation since its immediate result is the production of new digital media resources for teaching such as Open Educational Resources (OER). This study aims to determine teachers' DC through their participation in a MOOC training course and establish the extent to which DC better enables the production of OER. A group of 863 in-service teachers participated in the study. A 26-item validated questionnaire on DC and the use of OER was delivered to participants, and course facilitators' weekly reports were collected. An ordinal logarithmic regression was conducted to verify whether teachers who hold positive self-perceptions of DC are more prone to using OER in their teaching. Mean differences between traditional teaching and online teaching were also tested. Reports were content analysed using a SWOT matrix. Our model predicts that only in-service teachers that perceive themselves as digital experts can reach an intermediate level in the production of OER. Furthermore, online teaching significantly favours teachers' DC but is highly significant in OER production. The main implication is that training teachers' DC is required to prepare teachers for the use of OER; however, teacher education should first address teachers’ actual level of performance.
- Noise emission from alternative fuel vehicles: Study case(Elsevier, 2017-03-01) Ibarra Zárate, David Isaac; Ramírez Mendoza, Ricardo Ambrocio; López Caudana, Edgar Omar; IBARRA ZARATE, DAVID ISAAC; 301007; RAMIREZ MENDOZA, RICARDO AMBROCIO; 60733; LOPEZ CAUDANA, EDGAR OMAR; 69726; https://ror.org/03ayjn504Noise pollution has become a source of social tension, with economic development on one hand and quality of life on the other. The number of vehicles on the road is increasing constantly, especially in urban areas. As a consequence, environmental pollution has also increased, not only due to fuel emissions harmful to people, but also due to noise pollution; therefore, the control of the acoustic environment has turned out to be a key issue and a technological challenge. According to Ibarra et al. there have been recent studies on the quantification and characterization of noise emitted by vehicles in the near and far fields, but this kind of work has mainly been developed for internal combustion vehicles fuelled by diesel or petrol. With new emerging technologies aimed at improving world social and environmental conditions, new alternative fuel vehicles are appearing around the world, especially in large cities. These new vehicles have not yet been characterized regarding their noise emissions. The aim of this work is to characterize and quantify the level of noise emitted by alternative fuel vehicles, such as hybrid and electric vehicles, for both near and far fields. To achieve this, it would be very useful to incorporate simulations of noise mapping. Experimental results of this work demonstrate that hybrid and electric engines have made important contributions towards reducing engine noise in suburban and urban traffic, at least 10 dBA less than diesel or petrol vehicles; however, noise from the tyre-ground interaction remains the main source of noise, especially in suburban roads at high speeds.
- Identification of material properties using nanoindentation and surrogate modeling(Elsevier, 2016) Li, Han; Gutierrez, Leonardo; Toda, Hiroyuki; Kuwazuru, Osamu; Liu, WenliHangai, Yoshihiko; Kobayashi, Masakazu; Batres Prieto, Rafael; Tecnologico de MonterreyIn theory, identification of material properties of microscopic materials, such as thin film or single crystal, could be carried out with physical experimentation followed by simulation and optimization to fit the simulation result to the experimental data. However, the optimization with a number of finite element simulations tends to be computationally expensive. This paper proposes an identification methodology based on nanoindentation that aims at achieving a small number of finite element simulations. The methodology is based on the construction of a surrogate model using artificial neural-networks. A sampling scheme is proposed to improve the quality of the surrogate model. In addition, the differential evolution algorithm is applied to identify the material parameters that match the surrogate model with the experimental data. The proposed methodology is demonstrated with the nanoindentation of an aluminum matrix in a die cast aluminum alloy. The result indicates that the methodology has good computational efficiency and accuracy.
- Study of adsorption of citrate on Pt by CV and EQCM(Elsevier, 2008-07-01) Gonzalez Peña, Omar Israel; Chapman, Thomas W.; Vong, Yunny Meas; Antaño-López, René; GONZALEZ PENA, OMAR ISRAEL; 162547; CIDETEQ; Instituto Tecnológico y de Estudios Superiores de MonterreyCitrates are frequently used as additives in the electrodeposition of metals such as manganese in order to improve deposit characteristics and process efficiency. Nevertheless, few studies have been reported on the mechanism of citrate adsorption. This paper presents the results of a study of citrate adsorption onto platinum from solutions of various citrate concentrations in 0.1 M HClO4. Simultaneous observations with an electrochemical quartz crystal microbalance (EQCM) and cyclic voltammetry (CV) indicate that with increasing concentrations, up to 10−2 M, the fractional surface coverage by citrate rises to 13% in the region of hydrogen UPD, and the anodic formation of PtO is inhibited and reduced by as much as 43%. Combination of EQCM with cathodic linear-sweep voltammetry shows the interactions of citrate with platinum oxidation and hydrogen UPD. Thus, this approach reveals changes in additive adsorption with potential and indicates in particular the influence of the additive on the adsorption and desorption of hydrogen as a step in understanding metal deposition.