The implementation of UAVs (unmanned aerial vehicles) as an operational tool in the AECO (architecture, engineering, construction, operation) sector has significantly changed structural inspection tasks. To harness the potential of cutting-edge technology, this research compared the performance of conventional and immersive drone technology (FPV (first-person view) goggles and motion control) in simulated scenarios. 28 engineering students participated in two activities that recreated realistic structural inspection environments: detecting structural anomalies and flying through an aerial obstacle course. The results showed that the immersive drone outperformed the conventional drone in terms of efficiency and effectiveness, yielding more findings, fewer collisions and more accurate flight paths. Suggesting that the learning curve of the immersive interface provided advantages in control and spatial perception tasks, projecting its potential benefits for the industry.

Shell structures are primarily subjected to compressive stresses if their geometry is adjusted to the applied loading. Still, the geometry in a real environment usually deviates from an optimal form for load-bearing due to tolerances and architectural demands, thus causing additional bending moments (m) and normal forces (n). The use of textile-reinforced concrete (TRC) makes it possible to reduce thickness and thus the dead weight of a shell, though it also increases the sensitivity for deviations from perfect conditions. Additionally, textile reinforcement typically consists of two orthogonally aligned reinforcement layers of yarns, while the principal stress directions relevant to the shell design typically diverge from the yarn orientation. Hence, the cross-section suffers a reduced resistance due to the anisotropic material properties of the textile reinforcement. In this paper, we investigate the load-bearing capacity of existing TRC-shell structures that were created with a free form-finding approach. Given the anisotropy of the textile reinforcement, the analysis of the shell must not only consider the n-m interaction but also the principal stress direction for each specific location and load situation within the structure. This is considered by the verification concept presented here, which follows the semi-probabilistic design format from the European Codes. It could be shown that this new methodology for assessing free form shells can be used identify the most critical parts of such shells.

A simple model for average backscatter power from clutter is developed for indoor RF sensing applications and verified through measurements. A narrowband 28 GHz sounder used a quasi-monostatic radar arrangement with an omnidirectional transmit antenna illuminating an indoor scene and a spinning horn receive antenna less than 1 m away collecting backscattered power as a function of azimuth. Median average backscatter power was found to vary over a 12 dB range, with average power generally decreasing with increasing room size. A deterministic model of average backscattered power dependent on distance to nearest wall and clutter reflection coefficient reproduces observations with 4.0 dB RMS error.

The use of video games is proposed as an effective strategy to address the growing lack of student motivation by integrating the playful dynamics inherent to these resources with the teaching-learning process. In this study, perception and knowledge surveys were administered before and after the use of an educational video game focused on cell biology content. The sample consisted of 40 students who are currently enrolled in or have previously taken courses related to this discipline. The results showed an average increase of 0.07 points in the accuracy rate, suggesting that the video game has significant potential as a reinforcement tool. However, student feedback also revealed various limitations present in the pilot version of the game. These findings demonstrate that the use of video games is a didactic tool with high potential for addressing complex content, such as that found in the field of cell biology.

In this paper we develop an identification technique for the multipath wireless channel utilizing a discrete sum distribution approximation. We focus on three of the main distributions for the multi-path channel: Rayleigh, Rice and Nakagami-m. The distributions are approximated using a weighted sum of a Rayleigh and up to three distributions. The estimation procedure is based on the Maximum Likelihood approach and Akaike's Information Criterion. We show via simulations that when the channel is Rayleigh distributed, the estimation yields the correct Rayleigh distribution. When the channel distribution is Rice, the estimation yields one Rician term, whilst when the true channel distribution is Nakagami- m, the estimation yields an adequate approximation with a Rayleigh and Rice terms.

Recently, interest in collaborative management practices in high-rise building design has grown significantly, as evidenced by an increasing number of publications in the last decade. However, existing research does not comprehensively address the effectiveness of these practices in design performance, nor does it provide a prioritized list to facilitate their implementation to improve collaboration and coordination in this crucial phase. This study aims to propose collaborative management practices specifically designed for the design phase in high-rise building projects to enhance the productivity of design teams and ensure project success. A three-step methodology was adopted: (1) identify activities that do or do not contribute value to design management; (2) describe relevant collaborative management practices; and (3) validate the relationship between these practices and design team performance. As a result, 15 key practices were defined, highlighting the five most important: phased project planning, long- term supplier relationships, solution implementation and tracking, verification and documentation of results, and efficient organization of project information. While these practices have proven effective, their validation in real projects and adaptation to different contexts, such as smaller-scale projects, are areas for future study.

Currently, most multi-level converters are controlled through the use of voltage source based control techniques, such as space vector modulation or multi -carrier based modulation. However, in many applications such as field oriented drives, a high bandwidth current control is more desirable. In this paper, the concept of active hysteresis control is set forth. Hysteresis current control (H CC) based voltage source converters (VSCs) have several advantages like fast dynamic response, over-current protection, insensitive to load parameter variation and ease of implementation. The application of HCC technique for two-level VSCs is well established and few modifications of the same are also reported to operate with variable or constant switching frequency in case of multilevel converters. However, control of the dc-link voltage drift is commonly implemented using classical linear control techniques in a cascaded control loop, thus limiting the dynamic response. In this work, an active hysteresis control technique is proposed and implemented in a four level Quasi Nested Converter, for current tracking and including dc-link volt-age drift compensation control. This approach has the advantage of a reduced implementation complexity compared to classical linear techniques and Model Predictive Control (MPC) strategies. The proposed control technique is explained and implemented for the four level Quasi Nested Converter topology, considering the voltage drift phenomena. The topology and control strategy were implemented using PLECS simulation software and verified by Hardware-in-the-loop (HIL) results; its performance was evaluated under different operational conditions. The proposed control strategy is capable to mitigate the dc-link voltage drift, while keeping track of the load currents.

Low productivity in high-rise building projects represents a recurring challenge in Chile, often linked to deficiencies in management during the design phase. This process, crucial for project coordination and success, is affected by fragmented roles, lack of integrated methodologies, and limited adoption of internationally recommended practices. Despite its relevance, little research has addressed how this stage is currently managed in the Chilean context. This study evaluates the design management of high-rise building projects by identifying design processes, characterizing the temporary organization formed by professionals, and analyzing their role participation. The methodology included a literature review, expert validation, surveys, and interviews with industry professionals. A total of 22 specific processes were identified across Preliminary, Basic, and Detailed design phases, and 12 roles were mapped to these processes. The study compares current practices with good practices from the literature, including project management standards and Lean, BIM, and Agile methodologies. The results reveal discrepancies between ideal and actual role involvement, operational fragmentation, and limited application of management tools. These findings highlight key areas for improvement in the Chilean construction sector and provide a foundation for future research.

This study explores the determinants influencing adherence to psychological therapy among university students in a Chilean clinical setting. Using a multinomial logistic regression model, we examine the impact of various factors, including sociodemographic characteristics, academic performance, and clinical supervisor attributes on therapy adherence. Key findings indicate that adherence is significantly affected by patient compliance rates, hours in therapy, and the quality of clinical supervision, with a notable gender difference showing higher adherence rates among female patients. The study underscores the importance of patient-provider relationships and highlights the role of personalized support in enhancing adherence to therapy. These results have practical implications for mental health service optimization in educational institutions and contribute to a more comprehensive understanding of the factors that influence therapy adherence in higher education contexts. Future research is recommended to assess the universality of these findings across diverse cultural and educational settings.

Measuring the growth of a country can be affected by different factors, such as services available to the population, political-social stability and financial health of both households and companies, among others. In general, with these indicators, what is sought is to be able to find the phenomena or factors that explain what is happening. A case that is always of public interest is knowing the financial status of a company, given the impact they have on society, whether they are micro, small, medium or large companies. Based on this, and given that today the information inputs are different and extensive, which can come from government entities as well as private ones, this work seeks to establish an explanation of what are the factors that influence whether a company may fall into default. To do this, a multivariate econometric analysis is used, through which it has been established that factors such as the number of partners of a company are not predominant factors in the default of a company, unlike the number of workers or assets.

Power quality is a critical concern, especially for voltage sensible equipment whose performance is highly dependent on the stability and reliability of the electrical supply. Disturbances such as voltage sags, swells, harmonics, and interruptions are characterized by deviations in voltage, current, or frequency that can lead to equipment malfunction or failure. Sensitive applications, including medical systems in hospitals, educational institutions, and correctional facilities, are particularly vulnerable, with outages that can result in significant o p erational and economic losses. To mitigate these issues, several solutions based on power electronics have been developed, among which the Dynamic Voltage Restorer (DVR) is widely recognized as one of the most effective and cost-efficient s o lutions. T h e D V R i s a power electronics-based device designed to detect and compensate for voltage sags in real time. This paper presents a dynamic voltage restorer, based on a Nine-Switch Converter Solid State Transformer (NSC-SST) configuration. Results under voltage-sag operation have been obtained using real-time simulation based on a hardware in the loop (HIL) control planform. These results showed that the proposed NSC-SST DVR presents several advantages such as: simple topology when compared with classical SST based on an arrangement of two-level voltage source converters, capable to operate under voltage-sag condition either with classical oriented control or Finite-Set Model Predictive Control scheme.

We measured human-induced blockage for a fixed wireless link at 140 GHz in a controlled indoor environment for a 5 m link distance with both the transmitter and receiver at the same height of 0.8 m. Humans of different complexities walked at a speed of 0.5 m/s on average and obstructed perpendicularly the line-of-sight of the link at different positions and thus, at different radius of the 1st Fresnel zone of the link. We found that the width of a person was inversely proportional to the observed mean attenuation, and for the same position two persons could produce fades of up to 7 dB in difference. Fade durations were well aligned with the width of each person and the average walking speed of the subjects, ranging from 470 to 660 ms in the median.

Modern Architecture, Engineering, and Construction (AEC) projects require integrated approaches for efficiency and sustainability. Lean Construction (LC) optimizes processes and minimizes waste, but cultural resistance and limited stakeholder engagement hinder its adoption. Enterprise Architecture (EA) aligns strategies with technological and operational processes, enhancing decision-making and resource use. This study examines the combined impact of LC and EA on project outcomes, utilizing practices, developing strategies, and validating findings through a focus group at a large engineering firm. Results indicate that integrating these frameworks improves project coordination, reduces inefficiencies, and fosters continuous improvement, despite challenges like resistance to change and training gaps. The study highlights interdisciplinary approaches that unite technology, processes, and people. Combining LC with a robust EA framework enhances collaboration, agility, and alignment, promoting sustainable innovation in the AEC sector.

This article presents the creation of the educational software called “MathQuest”, a desktop application for Windows, created to reinforce first degree equations by playing. The educational software consists of helping”Piolina”(a little bird that needs to learn simple equations) to overcome 3 levels of difficulty, with 4 exercises each, based on different mathematical learning objectives proposed by the Chilean Ministry of Education. MathQuest also incorporates different gamification elements to motivate users to learn while playing. The validation of the educational software was carried out with 40 users, who participated in a pre-test, the MathQuest test, a post-test and an opinion questionnaire, in order to evaluate if the software created was able to contribute to the detected problem. It was observed that the application is effective in educational terms and that it also motivates users to occupy it, keeping them entertained. However, they suggest that the difficulty of some exercises was high, and that the time per exercise and the game interface could be improved. These findings indicate that MathQuest can improve to achieve its goal, but that it is on the right track.

Backscatter power measurements are collected to characterize indoor radar clutter in monostatic sensing applications. A narrowband 28 GHz sounder used a quasi-monostatic radar arrangement with an omnidirectional transmit antenna illuminating an indoor scene and a spinning horn receive antenna offset vertically (less than 1 m away) collecting backscattered power as a function of azimuth. Power variation in azimuth around the local average is found to be within 1 dB of a lognormal distribution with a standard deviation of 6.8 dB. Backscatter azimuth spectra are found to be highly variable with location, with cross-correlation coefficients on the order of 0.3 at separations as small as 0.1 m. These statistics are needed for system-level evaluation of RF sensing performance.

Environmental sustainability and circular economy are gaining more and more attention by the scientific and industrial communities. This is leading to the implementation of new eco-friendly materials in several sectors. The development of new third-generation photovoltaic cells, named dye-sensitized solar cells (DSSCs), produced by using microbial dyes, is recently gaining more interest in meeting the demand of sustainable devices. The present research is aimed to the screening of different microbial strains, cultivated under controlled fermentation processes, for producing dyes for DSSCs development. The microbial pigments obtained have been characterized by HPLC-DAD-ESI-MS analyses and evaluated for their suitability as photosensitizers. The absorbance intensity was measured by UV-vis, while the devices' photovoltaic parameters and impedance characteristics were obtained by applying Photoelectrochemical and Electrochemical Impedance Spectroscopy (EIS) analyses and IV measurements. Among the microbial pigments evaluated, the best results have been reached out both when the single carotenoidic extract enriched in astaxanthin, produced by Paracoccus carotinifaciens, and when the extracts from Talaromyces atroroseus GH2 and Paracoccus bogoriensis BOG6 have been applied in co-sensitization, obtaining the highest efficiencies values of 0.36% and 0.34% respectively. Even though the photovoltaic parameters of the implemented devices are low compared with those obtained by using synthetic dyes, the presented results denote an important achievement towards the development of greener solar cells using natural dyes obtained by microbial sources.

This work presents a novel dataset designed to support predictive modeling of income declaration behavior in the University Credit Solidarity Fund (FSCU) program of Chile. Using institutional records from the Pontificia Universidad Católica de Valparaíso, we prepared a structured and anonymized dataset that captures academic, financial, and demographic variables relevant to student loan administration. We describe the data extraction and preprocessing pipeline, including entity modeling, feature engineering, and the creation of a relational database. As a baseline evaluation, we conducted initial experiments using 15 machine learning algorithms via PyCaret, aiming to predict whether a student who previously submitted income declarations would cease to do so. Although no hyperparameter tuning or data balancing was applied, the results offer a solid foundation for future experimentation. Boosting-based classifiers-particularly XGBoost-achieved the best performance, with accuracy and AUC exceeding 96%. This contribution addresses the lack of publicly available, context-sensitive datasets for modeling conditional repayment schemes in higher education finance. Future work includes dataset publication, class balancing, and explainability analysis.

This paper proposes a Partial Power Dual Active Bridge (PP-DAB) converter topology for the dc-dc conversion stage of fast electric vehicle (EV) charging applications. The PP-DAB operates by processing only a fraction of the total power, significantly reducing conduction and switching losses while enhancing efficiency and power density. The operation principle of the proposed topology is theoretically analyzed, and simulations are conducted to evaluate its performance. Results demonstrate that the 5.3 kW PP-DAB achieves an overall efficiency of 98%, outperforming the conventional full-power Dual Active Bridge (DAB) converter, which achieves 94%. Additionally, the processed power ratio is limited to 0.42, meaning only 42% of the total power is processed through the converter, leading to improved thermal performance and reliability. A comparative analysis with the conventional DAB highlights the benefits of the proposed topology, making it a promising solution for high-power fast EV charging.

Mathematical modeling is recognized as a cornerstone of contemporary mathematics education because it enables students to connect real-world phenomena with mathematical formulations and solutions. However, its implementation in school settings poses significant didactic and logistical challenges. In parallel, Virtual Reality (VR) has emerged as an educational technology capable of generating immersive, contextualized experiences, although its application to mathematical modeling processes remains nascent. This article presents the technical and pedagogical aspects of designing an immersive educational simulation in VR, with the goal of exploring how such an environment influences the mathematical modeling process in secondary education students. The article examines its pedagogical and technical foundations and its potential to enrich the learning of mathematical modeling through immersive environments. The experience, titled “Painting a Room,” poses a contextualized task in which students must manage a budget to paint a room. The design aligns with the phases of a mathematical modeling cycle and is structured according to the stages of the Design Science Research Methodology (DSRM). The simulation is currently under development. As results, we present characteristic features of the simulation’s design and main flow, and how these relate to a mathematical modeling process; moreover, we operationalize the phases of the modeling process within this immersive experience. We highlight the relevance of the technology for enabling the validation of students’ mathematical models.

Building Information Modeling (BIM) enables the creation of digital twins for physical assets like buildings and infrastructures. To accurately represent the actual structural behavior, it is essential to calibrate these virtual models using real on-site measurements. This process is crucial as on-site damages can compromise key mechanical attributes, affecting the asset's safety and integrity. Typically, calibration involves manual tasks such as modifying structural databases and updating damaged element properties, which can introduce errors and complexities. This paper proposes using Robotic Process Automation (RPA) protocols to automate the calibration of BIM structural models. This enhances the integration of structural damages into BIM models, improving interoperability between architectural and structural federated models. A case study on a real steel bridge demonstrates the effectiveness of the proposed RPA tool.