Resonance-based procedure for locating failed luminaires in AGL systems

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.IEEE Aeronautical ground lighting (AGL) systems provide a visual reference for aircraft during airport operations. Fast detection and location of failed luminaires is an important safety concern in AGL systems. In the event of luminaire failure, AGL transformers introduce harmonic currents. Resonances can increase harmonics, worsening the problem. This paper presents analytical expressions for determining resonance frequencies in AGL systems, as well as a simple procedure based on these expressions for locating failed luminaires from measurements.Postprint (author's final draft

Resonance-Based Procedure for Locating Failed Luminaires in AGL Systems

Aeronautical ground lighting (AGL) systems provide a visual reference for aircraft during airport operations. Fast detection and location of failed luminaires is an important safety concern in AGL systems. In the event of luminaire failure, AGL transformers introduce harmonic currents. Resonances can increase harmonics, worsening the problem. This paper presents analytical expressions for determining resonance frequencies in AGL systems, as well as a simple procedure based on these expressions for locating failed luminaires from measurements

Effects of video game-based learning on project management in engineering

In recent years, higher education has undergone a significant transformation, driven by technological advancements and an increasing recognition of the various ways students engage with information. One innovative approach that has gained prominence is Video Game-Based Learning (VGBL). This shift from traditional teaching methods to a more dynamic and engaging learning environment reflects a broader acknowledgment of the need to adapt education to the evolving preferences and expectations of digitally-native students. VGBL represents a strategic response to the changing dynamics of education. By integrating elements of gameplay, simulations, and virtual environments into the curriculum, educators aim to create a more dynamic and participatory educational experience. As technology plays an increasingly integral role in our daily lives, the incorporation of VGBL in higher education not only aligns with the preferences of the current student population but also addresses the challenge of keeping education relevant and engaging. Therefore, this study explores the use of VGBL in project management in higher education, examining its potential benefits.The context of this study is situated at the University of La Rioja (Spain). The focus is on project management education within the fourth-year curriculum of the Mechanical Engineering B.Sc., Electric Engineering B.Sc., and Electronic Engineering B.Sc. programs. The cohort for this study comprises 44 engineering students actively participating in the project management course during the fall semester of 2023. It is pertinent to note that enrollment in this course is compulsory, underscoring its significance within the academic trajectory of these students.The creation of video games was facilitated using the SGAME tool, an authoring tool for easily creating educational video games from the Polytechnical University of Madrid (https://sgame.etsisi.upm.es/). In a preliminary phase, four different games (Mario Bross, Floppy Bird, Onslaught Arena, and Captain Rogers) were generated with identical content (20 questions related to a specific theme), allowing students the option to choose the game that best suited their preferences. This resource was conceived as an optional activity for students, and approximately 77% of them participated. A pre-test/post-test questionnaire was utilized to determine how well the use of video games had improved the acquisition of the content covered in the game. The results obtained suggest the positive impact on students performance, with statistically significant differences between the post-test and pre-test values for those students who played the video games. Results also indicate a moderate correlation between the average time a student spent playing and completing the video games and the number of correct answers to questions related with the content covered in the games in the final exam

Atmospheric pressure air plasma treatment of glass substrates for improved silver/glass adhesion in solar mirrors

Atmospheric pressure air plasma treatment was applied to glass substrates to improve the adhesion of the reflective silver layer of mirrors used in solar power systems. This treatment attempts to prevent problems related to the detachment of this layer that affect its energy performance. Untreated and plasma treated glass substrates were subjected to a spray coating process to fabricate mirrors. Chemical characterization by X-ray Photoelectron Spectroscopy (XPS) and measurements of the water contact angle (WCA) were undertaken on the glass substrates before the plating process. The reflectivity of the mirrors was studied by spectrophotometry in the wavelength range of 2802500 nm, and the adhesion between the glass substrates and the silver layers was measured by pull-off tests. In order to determine the relationship between the parameters of the plasma treatment and the adhesion and reflectivity of the mirrors, different combinations of treatment speeds and gap distances between the glass substrates and the plasma nozzle were used. It was observed that the plasma treatment has a cleaning effect and forms oxygen-based functional groups that promote the hydrophilicity of the glass substrates. This double effect resulted in improved adhesion of the silver layer to the plasma treated substrates, with no significant loss of solar reflectance of the mirrors. The plasma treatment with the lowest gap distance (2 mm) and the lowest speed (1 m/min) achieved the best results in this work. It brought an improvement of 85.8% in the breaking strength of the untreated glass mirror and no significant variation in the solar reflectance in as-fabricated conditions. After accelerated aging, it maintained an improvement of 27.2% in the breaking strength and showed higher solar reflectance than the untreated glass mirror. © 2017 Elsevier B.V

Entanglement without Dissipation: A Touchstone for an exact Comparison of Entanglement Measures

Entanglement, which is an essential characteristic of quantum mechanics, is the key element in potential practical quantum information and quantum communication systems. However, there are many open and fundamental questions (relating to entanglement measures, sudden death, etc.) that require a deeper understanding. Thus, we are motivated to investigate a simple but non-trivial correlated two-body continuous variable system in the absence of a heat bath, which facilitates an \underline{exact} measure of the entanglement at all times. In particular, we find that the results obtained from all well-known existing entanglement measures agree with each other but that, in practice, some are more straightforward to use than others

Atmospheric plasma-polymerization of hydrophobic and wear-resistant coatings on glass substrates

In order to find a coating that promotes both the wear resistance and the hydrophobicity of glass, a non-thermal atmospheric jet plasma-polymerization system with mixtures of two precursors at different proportions were used. (Heptadecafluoro-1,1,2,2-tetrahydrodecyl)trimethoxysilane (FLUSI) was used to promote the hydrophobicity, due to its fluorocarbon chain. Aminopropyltriethoxysilane (APTES) was used to enhance the wear resistance of the surface. The key aspect of the present work consists of determining the optimal mixture of precursors that produces a satisfactory coating in both characteristics; since coatings based on FLUSI have a low wear resistance and those based on APTES have a hydrophilic character. Scanning electron microscopy (SEM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), lap-shear tests, static water contact angle (WCA), tribological tests, profilometry measurements and energy dispersive X-ray spectroscopy (EDX) were used to analyze the coatings. It is believed that the upper limit of hydrophobicity that can be attained by modifying of the surface chemistry (WCA of ~120°) has been achieved. It was observed that the wear resistance depends on the thickness and the SiOSi content of the coatings. These appear to be directly related to the proportion of APTES in the mixture. The sample that was coated with 50% of APTES and 50% of FLUSI provided the best combination of hydrophobicity and wear resistance. It showed the highest WCA (123.2°±1.5) because it has a high fluorocarbon content and the highest CF3 content. Its wear resistance is considerably better than that of the uncoated glass and is one of the highest exhibited by the hydrophobic samples

Hydrophobicity attainment and wear resistance enhancement on glass substrates by atmospheric plasma-polymerization of mixtures of an aminosilane and a fluorocarbon

Mixtures of different proportions of two liquid precursors were subjected to plasma-polymerization by a non-thermal atmospheric jet plasma system in a search for a coating that achieves a hydrophobic character on a glass substrate and enhances its wear resistance. 1-Perfluorohexene (PFH) was chosen as a low-surface-energy precursor to promote a hydrophobic character. Aminopropyltriethoxysilane (APTES) was chosen for its contribution to the improvement of wear resistance by the formation of siloxane bonds. The objective of this work was to determine which of the precursors' mixtures that were tested provides the coating with the most balanced enhancement of both hydrophobicity and wear resistance, given that coatings deposited with fluorocarbon-based precursors such as PFH are usually low in resistance to wear and coatings deposited with APTES are generally hydrophilic. The coatings obtained were analyzed by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Fourier Transform Infra-Red (FTIR) spectroscopy, X-ray Photoelectron Spectroscopy (XPS), static Water Contact Angle (WCA) measurements, tribological ball-on-disc tests and contact profilometry. A relationship between the achievement of a hydrophobic character and the modifications to roughness and surface morphology and the incorporation of fluorocarbon groups in the surface chemistry was observed. Also, it was seen that the wear resistance was influenced by the SiOSi content of the coatings. In turn, the SiOSi content appears to be directly related to the percentage of APTES used in the mixture of precursors. The best conjunction of hydrophobicity and wear resistance in this work was found in the sample that was coated using a mixture of APTES and PFH in proportions of 75 and 25%, respectively. Its WCA (100.2 ± 7.5°) was the highest of all samples that were measured and more than three times that of the uncoated glass (31 ± 0.7°). This sample underwent a change from a hydrophilic to a hydrophobic character. It also had the lowest wear rate of the hydrophobic samples obtained in this work, with a reduction of 28.8% in the wear rate of the uncoated glass

2M1 phlogopite–muscovite series minerals at increasing pressure to 9 GPa. I Atomic volumes and compressibilities

Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. Authors are thankful to Andalusian project P18-RT-3786 for financial support, and to the Computational Centers of the University of Granada and CSIC for computational facilities.Muscovite (Ms) and phlogopite (Phl) series mineral is studied in the 2M1 polytype and modeled by the substitution of three Mg2+ cations in the three octahedral sites of Phl [KMg3(Si3Al)O10(OH)2] by two Al3+ and one vacancy, increasing the substitution up to reach the Ms [KAl2□(Si3Al)O10(OH)2]. The series was computationally examined at DFT using Quantum ESPRESSO, as a function of pressure from − 3 to 9 GPa. Crystal structure is calculated, and cell parameters, and geometry of atomic groups agree with experimental values. OH in the Mg2+ octahedrons are approximately perpendicular to the (001) plane, meanwhile when they are in Al3+, octahedral groups are approximately parallel to this plane. From Quantum Theory of Atoms in Molecules, the atomic basins are calculated as a function of the pressure, K+ and basal O show the largest volumes. The bulk excess volume (Vxs) and the excess atomic volumes are analyzed as a function of the composition and the pressure. K+, basal and apical O Vxs show a behavior similar to the bulk Vxs as a function of the composition, keeping qualitatively this behavior as a function of pressure; substituent atoms do not show a Vxs behavior similar to the bulk and their effect consequently is mostly translated to atoms in the interlayer space. Atomic compressibilities are also calculated. Atomic compressibilities are separated in the different sheets of the crystal cell. Atomic moduli of K and basal O are the lowest and the ones behaving as the bulk modulus of the series. The atomic bulk modulus of the H’s is different depending of their position with respect to the (001) plane.CRUE-CSICAndalusian project P18-RT-378