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An Interface Design Method Based on Situation Awareness and Immersive Analytics for Augmented and Mixed Reality Decision Support Systems in Construction
No full textResearch on augmented reality (AR) and mixed reality (MR) demonstrated their potential to support decision-making in construction. However, most efforts emphasized technological advancements, often overlooking how to present and interact with information to effectively support decision-making in AR/MR environments. This study proposes an interface design method that integrates situation awareness (SA) and immersive analytics (IA), two complementary frameworks that address user information needs and immersive interaction design. The method guides the design of AR/MR interfaces by aligning information content, presentation, and interaction with SA requirements and IA design principles. To evaluate its effectiveness, the method was applied to develop AR and MR interface prototypes for a simulated decision-making task involving field managers during indoor construction activities of high-rise construction projects. Results show high levels of SA achieved by participants, with no statistically significant differences between AR and MR interfaces, demonstrating the method’s effectiveness to support SA in both environments. The proposed method provides a structured approach for designing immersive interfaces that enable better perception, comprehension, and projection in dynamic construction scenarios. Moreover, it provides designers with practical guidance for interface development and allows practitioners to assess existing AR/MR solutions based on their capacity to enhance SA through IA
Presentation of Dossier #23. New and old debates around state housing:drifts of housing policy in contexts of crisis
No full textPresentación del Dossier #23. Nuevos y viejos debates en torno a la vivienda estatal: derivas de la política habitacional en contextos de crisi
Thermal and quantum phase transitions in a holographic anisotropic Dirac semimetal: a theoretical model for semi-Dirac critical anisotropy in strongly interacting condensed matter using the AdS/CFT correspondence
No full textTesis (Magíster en Física)--Pontificia Universidad Católica de Chile, 2025En esta tesis se construyó un modelo teórico de un sistema fuertemente interactuante en 2+1-dimensiones a través de la correspondencia holográfica AdS/CFT. En dicho modelo se detectó, mediante técnicas numéricas y analíticas, una transición de fase tipo semi-Dirac a temperatura cero y temperatura finita. Además, se identificó la transición de temperatura cero como una transición de fase cuántica mediante el escaleo del ratio de viscosidad-densidad de entropía a bajas temperaturas. Además, se comprobó que este modelo rompe la cota KSS propuesta por Kovtun, Son y Starinets, lo cual añade este modelo a la expansiva literatura de modelos holográficos que violan dicha cota.FondefCorfoFundación Copec U
Towards lifetime lubrication of wind turbine gearboxes: Technical and physical investigations on used oils
No full textModern geared wind turbines rely on the adequate performance of their lubricant to ensure optimum operation of their main gearboxes. Potential oil ageing mechanisms, such as oxidation or additive depletion, can degrade oil performance over time. An oil that performs satisfactorily throughout the entire life of the turbine can reduce the downtime, resources, and costs associated with oil changes or repairs. Therefore, the purpose of this study is to investigate the ageing of field oil through oil analysis and artificial ageing. In addition, the possibility of oil service life extension by top-treating used oils with additives was investigated. For the field oil evaluation, oil samples were taken from operating wind turbines with lifespans up to 16 years. The deterioration of their copper corrosion, foaming, and wear performance was assessed using standard tests and its influence on gearbox operation was identified. Although these properties had degraded to some extent, most oils continued to perform satisfactorily. To counteract oil ageing, top-treating (adding additives to the field oils) was performed to restore the corresponding properties of oils. Subsequent standard tests confirmed that this approach is generally effective, but there are still some potential problems. To further investigate the oils' lifespan limits, field oils were subjected to artificial ageing. This process involved oil heating and the artificial, accelerated consumption of anti-wear additives. Experimental results indicated that artificial ageing has only a minor influence on wear despite a significant reduction in additive concentration. In conclusion, proper monitoring of oils and timely top-treat have the potential to achieve lifelong wind turbine gearbox lubrication
A methodology for estimation of local black carbon and PM2.5 emissions in suburban zones. Case study of Santiago, Chile.
No full textThis work presents a methodology that combines CALPUFF dispersion model with novel estimates of local concentrations of black carbon and PM₂.₅ coming from fossil fuel (BC_ff, PM₂.₅_ff) and wood burning (BC_wb, PM₂.₅_wb), to improve local emission estimates without the need to specify boundary conditions. We have applied this methodology in three suburbs of Santiago, Chile — Colina, Melipilla and San José de Maipo (SJM) — during the cold season of 2021. For PM₂.₅_wb, local emission rates were estimated at 74.8 ton year⁻¹ for Colina, 93.3 ton year⁻¹ for Melipilla, and 24.3 ton year⁻¹ for SJM, which correspond to 0.5, 0.4, and 0.3 times the 2012 inventory, respectively. For BC_ff, the estimated emission rates were 2.2 ton month⁻¹ in Colina, 0.2 ton month⁻¹ in Melipilla, and 0.2 ton month⁻¹ in SJM, which represent 5.2, 0.7, and 2.8 times the respective values at each site according to the 2017 inventory. For both BC_wb and BC_ff, the peaks in local emissions corresponded to times of the day with higher levels of residential combustion and traffic activity. Dispersion modeling of BC_ff from Zone B (the studied suburbs) to Zone A (Greater Santiago) showed that the highest contributions occurred in July 2021 in the wee hours. Dispersion modeling of PM₂.₅_wb, PM₂.₅_ff, BC_wb and BC_ff from Zone A to Zone B and wind trajectory analysis suggest that non-local contributions reaching the studied suburbs originate not only from Santiago but also from nearby and distant localities. This novel methodology may be applied to any suburban area
WIP: Self-tracking Time-On-Task to promote self-organization skills in an Undergraduate Engineering Design Course
No full textThis is a work in progress. Time management, a key self-regulation ability, is crucial for students' academic achievement. Effective time management skills have been linked to academic success in Massive Open Online Courses. However, this has not been fully tested in a typical residential college setting where students are living on campus and working time bleeds in their personal time. In addition, research reveals that effective studying behaviors begin with becoming aware of your particular learning processes since we know that notions of time among students in higher education vary. The following work-in-progress research endeavor showcases a data-driven decision-making method for undergraduate engineering students to address the time spent on various design activities in an engineering design team-based course at an R1 institution in the United States. We adapted an intake form to report hours weekly in an engineering design course. For the first stage, using student input, we translated this data into individual dashboards that were returned to the student teams every two weeks. For the second stage, we plan to conduct interviews to understand the process. A further implementation of the tool involves using the data to make data-driven decisions at the curricular and planning level for instructors. Findings can be translated into the many engineering-design courses required by the ABET accreditation agency in the United States
Whose Stories are Told? Representation of English-Speaking Communities in EFL Textbooks
No full textIn times of change and reinvention, communities are developing collective meanings, ideas, and practices. Such social representations, cognitions, or thinking are always related to the social and cultural tensions in our society. With this in mind, we invite the Chilean ELT community (pre and in-service teachers of English as well as academics) to share their ELT research-based representations, thinking, and voices and be part of our biannual collective discussions
Research in Architecture, Design, City, and Territory: Among Scales, Agencies, and Territories in Latin America
No full textThis chapter introduces the structure of the book, organized with ten thematic axes that collect the best presentations of the “IV Congreso Intersecciones—2023”, organized in Santiago de ChileSantiago de Chile by Pontificia Universidad Católica de ChileChile, Universidad de ChileChile, Tecnológico de Monterrey (MexicoMexico) and Universidad de los Andes (ColombiaColombia). The chapter expresses the deep conviction of the editors about the importance of moments of intersection: spacesSpace of meeting and common reflection between different institutions, disciplines and contexts, which contribute to generating new visions on the role of research in architectureArchitecture, designDesign, cities and territories. This sharing is more important than ever for a region like Latin AmericaLatin America which finds itself facing many common challenges and which experiences just as many opportunities to present itself as an international reference on how to deal with the necessary changes in research activities and sustainable development.Canadian Institutes of Health ResearchInternational Collaboration for Capitalizing on Cost-Effective and Life-Saving Commodities (i4C) through the Research Council of Norway's Global Health & Vaccination Programme (GLOBVAC Project)Canadian Institutes of Health Research (the Government of Canada
Acute Bronchiolitis in Infants on Invasive Mechanical Ventilation: Physiology Study of Airway Closure
No full textObjectives: This study aimed to explore whether airway closure can be detected in patients with severe acute bronchiolitis on invasive mechanical ventilation.Design: Single-center prospective physiologic study carried out in 2023-2024.Setting: PICU in a tertiary-care general hospital.Patients: Infants with acute bronchiolitis undergoing invasive mechanical ventilation.Interventions: Under deep sedation and neuromuscular blockade, the mechanical ventilator, in a volume-controlled mode, was transiently set with a respiratory rate of five breaths/min, a tidal volume of 6 mL/kg of ideal body weight, positive end-expiratory pressure 0 cm H2O, a flow rate of 2 L/min, an inspiratory-expiratory ratio of 1:1, and a Fio2 of 1.0. After recording three breath cycles, the patient was returned to baseline ventilatory settings.Measurements and main results: We identified the presence of airway closure through the low-flow pressure-volume curve obtained from a pneumotachometer with a flow sensor placed at the Y-piece and simultaneously from the pressure-impedance curve and ventilation maps acquired using electrical impedance tomography. We included 12 patients, and airway closure was detected in seven of them. The median (interquartile range [IQR]) airway opening pressure was 14 cm H2O (IQR, 11-17 cm H2O). Patients with airway closure exhibited high levels of driving pressure, with a median of 16 cm H2O (IQR, 11-17 cm H2O), and low levels of respiratory system compliance, with a median of 0.41 mL/cm H2O/kg (IQR, 0.38-0.59 mL/cm H2O/kg). When these parameters were corrected for airway opening pressure, there was a significant decrease in driving pressure to 9 cm H2O (IQR, 8-12 cm H2O; p = 0.018) and a significant increase in respiratory system compliance to 0.70 mL/cm H2O/kg (IQR, 0.53-0.81 mL/cm H2O/kg; p = 0.018).Conclusions: Airway closure requiring high opening pressures can be detected in ventilated infants with acute bronchiolitis, and this phenomenon may impact respiratory mechanics