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Oportunidades para integrar la Comprensión de la inteligencia artificial en las clases de matemática de primaria: El caso de Chile
Get PDFEl estudio tuvo como propósito identificar las oportunidades de integración de las cinco ideas fundamentales de la iniciativa AI4K12 (Inteligencia Artificial para K12, según su traducción al español) en la enseñanza de las matemáticas de primaria en Chile. Las pautas de dicha iniciativa han resultado útiles para promover la integración de la inteligencia artificial en diversos contextos educativos, por lo que se adoptaron como marco de referencia para analizar un programa de estudio de matemática chileno mediante un análisis documental de carácter cualitativo. Tres especialistas evaluaron y codificaron veintiséis objetivos de aprendizaje (OA) utilizando una escala de conexión (nula, baja, media y alta) con cada una de las cinco ideas fundamentales: percepción, representación y razonamiento, aprendizaje, interacción natural e impacto social. Los resultados indican que las ideas de aprendizaje y representación y razonamiento presentan los mayores niveles de conexión con los OA de matemática. La idea de interacción natural muestra una conexión reducida, aunque detectable. Asimismo, se observa que las ideas de percepción e impacto social presentan vínculos menos explícitos. No obstante, se advierte que es posible integrar estas ideas a través de OA pertenecientes a los ejes de Datos y probabilidad y Geometría y medición
Care4Plant: Mobile application for informal caregivers
No full textInformal caregivers provide long-term, unpaid support to patients – usually family or friends – with serious illnesses. Although caregiving is essential, it can have adverse effects, e.g. physical and emotional exhaustion. Digital applications are a cost-effective alternative to manage these effects. However, applications for caregivers are usually centered on skill building and education rather than well-being, and general-purpose stress management applications – besides not specifically considering caregivers – frequently change and do not usually incorporate social aspects. To design a caregiver-centered application, we analyzed caregiver needs, specifically focusing on well-being aspects. We present Care4Plant, an application designed to measure the emotional dimension of caregivers’ burden based on the Zarit Burden Questionnaire, and suggest a set of mood improvement tasks accordingly. Care4Plant features a virtual plant that represents informal caregivers’ emotional well-being, allowing them to care for the plant through actions intended to manage their mental health and reduce stress, and to share their plant with other caregivers through a social network represented by a greenhouse. We conducted an evaluation of Care4Plant with nine users over two weeks. The results indicated good levels of usability and demonstrated that the approach of motivating users through the virtual plant was well-received
Experiences and voices of student teachers when reviewing an essay of their own authorship
Get PDFLa teoría del pensamiento deficitario responsabiliza a los estudiantes sobre sus dificultades en lectura y escritura, sin considerar sus prácticas discursivas como autores y evaluadores de sus escritos. Este trabajo tiene como propósito comprender los procesos de autorregulación que realizan estudiantes que ingresan a educación superior cuando revisan y reescriben un ensayo académico argumentativo de su autoría. Se utilizó un método cualitativo mediante la técnica de Protocolos de Pensamiento en Voz Alta (PPVA) a 60 estudiantes de Pedagogía en Lengua Castellana y Comunicación de dos universidades regionales de Chile. Los resultados muestran tres perfiles de escritores: estratégico, en desarrollo y emergente. Finalmente, se propone diseñar tareas de escritura que permitan a los estudiantes desarrollar estrategias de autorregulación, integrando en su planificación las prácticas vernáculas de los participantes
Enhanced MILP Approach for Long-Term Multi-Vessel Maritime Inventory Routing with Application to Antarctic Logistics
Get PDFThe maritime inventory routing problem (MIRP) integrates vessel routing and inventory management over a planning horizon to optimize logistical operations in marine environments. While existing models predominantly address short-term planning with single vessels, this research advances the field by presenting a tightened mixed-integer linear programming (MILP) model designed for long-term planning with multiple vessels. The proposed model leverages an improved mathematical formulation and state-of-the-art optimization solvers to enhance computational performance. To demonstrate its applicability, the model was evaluated using benchmark instances from the literature and new instances derived from the logistics of Chilean scientific bases in Antarctica, a challenging and underexplored maritime environment. The results show computational time reductions of up to 98% for small to medium-sized instances, achieved through the incorporation of valid inequalities into the model and the use of advanced hardware and solvers. For larger instances, optimal or near-optimal solutions were achieved within one hour for a planning horizon of 60 time units, with optimality gaps below 24.7% for a 120-time-unit horizon. These findings highlight the potential of the model to support decision-making in complex maritime logistics scenarios, extending its application to long-term, multi-vessel operations in remote and environmentally sensitive regions. The proposed framework provides a valuable tool for enhancing the sustainability and efficiency of maritime logistics systems
Experimental Investigation and Analysis of the Influence of Depth and Moisture Content on the Relationship Between Subgrade California Bearing Ratio Tests and Cone Penetration Tests for Pavement Design
Get PDFEvaluation of soil properties in highway design is an important but time-consuming task that does not always provide the necessary information to detect issues associated with changes in soil properties along the road project. California Bearing Ratio (CBR) tests are commonly used to identify soil properties and as an input in pavement design; however, it could be considered a slow test and, therefore, not always performed to the extent that it may be desired on the field. A comparison between CPT and CBR is performed in this work to obtain a correlation between them to be used in design. The effects of moisture content are also investigated in CPT and CBR to determine which conditions should be tested to obtain representative or design conditions for the pavement. A good correlation is found between CPT tip resistance and in situ CBR. It is observed that CBR and cone tip resistance change significantly for moisture contents up to 30 to 40%. It was found that tip resistance should be evaluated at a depth of 20 cm inside the subgrade to estimate adequate CBR values
Sural nerve injury risk during endoscopic gastrocnemius recession: Comparison of two approaches
No full textBackgrounds
The gastrocnemius recession was originally introduced as a method of treating isolated gastrocnemius contractures among pediatric population, however currently this procedure allows to treat various foot pathologies. Different modifications of open technique has been developed over the years and recently endoscopic approach become a widespread technique among many surgeons. It provides smaller incision and shorter operative time, however might be associated with the higher risk of sural nerve damage as a result of poor visualization. The aim of this study was to evaluate two different endoscopic approaches, introduced by Stryer and Lui, in terms of sural nerve injury.
Method
In 14 dissected legs the following measurements were assessed: 1) Distance between the sural nerve and cannula. 2) Distance to the sural nerve from the lateral portal and the medial portal when performing the Strayer technique. 3) Distance to the sural nerve from the lateral portal and the medial portal when performing the Lui technique.
Result
In both techniques the sural nerve was located dorsally to the cannula and no nerve damage was observed. In Lui technique the distance between cannula and the nerve was noticeably deeper than in Strayer method.
Conclusion
Both method of endoscopic gastrocnemius recession have similar risk of intraoperative sural nerve injury. Open method should always be considered as an alternative, especially for surgeons who lack experience in endoscopic procedures.
Level of evidence
I
Systematic Review of Studies Using Confirmatory Factor Analysis for Measuring Management Skills in Sustainable Organizational Development
Get PDFThis systematic review explores the most validated methodologies for measuring managerial skills that contribute to sustainable organizational development, with a focus on confirmatory factor analysis (CFA). Using PRISMA guidelines and the PICOS framework, a systematic search in the Web of Science (6810 articles) and Scopus (11,267 articles) identified 27 relevant studies. Our findings emphasize the significance of valid, reliable measurement scales for key managerial competencies, such as leadership, decision-making, communication, and teamwork, which enhance employability and foster sustainable management aligned with the Sustainable Development Goals (SDGs). CFA emerges as a robust technique for ensuring methodological rigor in competency assessment, confirming theoretical models with empirical data. This study identifies gaps in current measurement frameworks, advocating for expanding models to incorporate digital transformation, sustainability leadership, and crisis management skills. Additionally, it underscores the importance of developing context-specific instruments that reflect sectoral and cultural variations. This review contributes to management education and workforce development by providing a validated framework for assessing managerial skills, supporting organizations in aligning leadership training with sustainability-driven business goals. Our findings offer practical implications for designing competency-based curricula and corporate training programs to enhance organizational resilience in an evolving global landscape
Asymptotic structure of three-dimensional Maxwell Chern-Simons gravity coupled to spin-3 fields
No full textIn this work we analyze the asymptotic symmetries of the three-dimensional Chern-Simons (CS) gravity theory for a higher spin extension of the so-called Maxwell algebra. We propose a generalized set of asymptotic boundary conditions for the aforementioned flat gravity theory and we show that the corresponding charge algebra defines a higher-spin extension of the max-bms3 algebra, which in turn corresponds the asymptotic symmetries of the Maxwell CS gravity. We also show that the hs3max-bms3 algebra can alternatively be obtained as a vanishing cosmological constant limit of three copies of the
algebra, with three independent central charges
Rainwater Harvesting for Well Recharge and Agricultural Irrigation: An Adaptation Strategy to Climate Change in Central Chile
Get PDFWater scarcity in Chile, particularly in the Mediterranean region, has been exacerbated by prolonged drought and climate change. Rainwater harvesting systems (RHS) have emerged as viable solutions for addressing water shortages, particularly for agricultural irrigation and aquifer recharge. This study evaluated the implementation and efficiency of RHS in rural areas of the Biobío Region, Chile, through the design and construction of two pilot systems in Arauco and Florida. These systems were assessed based on their water collection capacity, storage efficiency, and monitoring of water level variations in wells after rainwater incorporation, using depth probes to quantify stored volumes. The hydrological design incorporated site-specific precipitation analyses, runoff coefficients, and catchment area dimensions, estimating annual precipitation of 861 mm/year for Arauco and 611 mm/year for Florida. The RHS Arauco collected and stored 40 m3 of rainwater in a flexible tank, while RHS Florida stored 10 m3 in a polyethylene tank, demonstrating the effectiveness of the system. Additionally, we analyzed the economic feasibility and quality of harvested rainwater, ensuring its suitability for agricultural use according to Chilean regulations. The cost-effectiveness analysis indicated that the cost of stored water was 841.07 USD/m3 for Florida, highlighting larger systems are more cost-effective owing to economies of scale. The Net Present Value (NPV) was calculated using a discount rate of 6% and a useful life of 10 years, yielding CLP 10,812.7 USD) for the Florida and CLP 2505.8 USD) for the Arauco site. The results indicate that both projects are financially viable and highly profitable, offering rapid payback periods and sustainable long-term benefits. RHS significantly contributes to water availability during the dry season, reducing dependence on conventional water sources and enhancing agricultural sustainability. Based on the evaluation of the cost–benefit, water availability, and infrastructure adaptability, we infer the feasibility of large-scale implementation at locations with similar characteristics. These findings support the role of RHS in sustainable water resource management and strengthening rural resilience to climate variability, highlighting their potential as an adaptation strategy to climate change in water-scarce Mediterranean regions
Multiscale Hybrid-Mixed Methods for the Stokes and Brinkman Equations—A Priori Analysis
No full textThe multiscale hybrid-mixed (MHM) method for the Stokes operator was formally introduced in [R. Araya et al., Comput. Methods Appl. Mech. Engrg., 324, pp. 29–53, 2017] and numerically validated. The method has face degrees of freedom associated with multiscale basis functions computed from local Neumann problems driven by discontinuous polynomial spaces on skeletal meshes. The two-level MHM version approximates the multiscale basis using a stabilized finite element method. This work proposes the first numerical analysis for the one- and two-level MHM method applied to the Stokes/Brinkman equations within a new abstract framework relating MHM methods to discrete primal hybrid formulations. As a result, we generalize the two-level MHM method to include general second-level solvers and continuous polynomial interpolation on faces and establish abstract conditions to have those methods well-posed and optimally convergent on natural norms. We apply the abstract setting to analyze the MHM methods using stabilized and stable finite element methods as second-level solvers with (dis)continuous interpolation on faces. Also, we find that the discrete velocity and pressure variables preserve the balance of forces and conservation of mass at the element level. Numerical benchmarks assess theoretical results