Simulation heat transfer fluids efficiency and molten salts in heat collecting elements in concentrating solar power

Postprint (published version

Analysis of assessment tools of Engineering degrees

This work presents an analysis of the assessment tools used by professors at the Universitat Politécnica de Catalunya to assess the generic competencies introduced in the Bachelor’s Degrees in Engineering. In order to conduct this study, a survey was designed and administered anonymously to a sample of the professors most receptive to educational innovation at their own university. All total, 80 professors responded to this survey, of whom 26% turned out to be members of the university’s own evaluation innovation group (https://www.upc.edu/rima/grups/grapa), GRAPA. This percentage represents 47% of the total GRAPA membership, meaning that nearly half of the professors most concerned about evaluation at the university chose to participate. The analysis of the variables carried out using the statistical program SPSS v19 shows that for practically 49% of those surveyed, rubrics are the tools most commonly used to assess generic competencies integrated in more specific ones. Of those surveyed, 60% use them either frequently or always. The most frequently evaluated generic competencies were teamwork (28%), problem solving (26%), effective oral and written communication (24%) and autonomous learning (13%), all of which constitute commonly recognized competencies in the engineering profession. A two-dimensional crosstabs analysis with SPSS v19 shows a significant correlation (Asymp. Sig. 0.001) between the type of tool used and the competencies assessed. However, no significant correlation was found between the type of assessment tool used and the type of subject, type of evaluation (formative or summative), frequency of feedback given to the students or the degree of student satisfaction, and thus none of these variables can be considered to have an influence on the kind of assessment tool used. In addition, the results also indicate that there are no significant differences between the instructors belonging to GRAPA and the rest of those surveyed.Preprin

Analysis of Assessment Tools on Engineering Degrees

This work presents an analysis of the assessment tools used by professors at the Universitat Politécnica de Catalunya to assess the generic competencies introduced in the Bachelor’s Degrees in Engineering. In order to conduct this study, a survey was designed and administered anonymously to a sample of the professors most receptive to educational innovation at their own university. All total, 80 professors responded to this survey, of whom 26% turned out to be members of the university’s own evaluation innovation group (https://www.upc.edu/rima/grups/grapa), GRAPA. This percentage represents 47% of the total GRAPA membership, meaning that nearly half of the professors most concerned about evaluation at the university chose to participate. The analysis of the variables carried out using the statistical program SPSS v19 shows that for practically 49% of those surveyed, rubrics are the tools most commonly used to assess generic competencies integrated in more specific ones. Of those surveyed, 60% use them either frequently or always. The most frequently evaluated generic competencies were teamwork (28%), problem solving (26%), effective oral and written communication (24%) and autonomous learning (13%), all of which constitute commonly recognized competencies in the engineering profession. A two-dimensional crosstabs analysis with SPSS v19 shows a significant correlation (Asymp. Sig. 0.001) between the type of tool used and the competencies assessed. However, no significant correlation was found between the type of assessment tool used and the type of subject, type of evaluation (formative or summative), frequency of feedback given to the students or the degree of student satisfaction, and thus none of these variables can be considered to have an influence on the kind of assessment tool used. In addition, the results also indicate that there are no significant differences between the instructors belonging to GRAPA and the rest of those surveyedPostprint (published version

Determination of the radon diffusion coefficient of thin polyethene and aluminium foils used as single or multilayer configuration barriers

[EN] Radon is a radioactive noble gas exhaled from the soil that can reach high concentrations in enclosed spaces. As elevated concentrations cause serious health problems, legislation has been put in place in many countries to regulate the limit concentration and even establish mitigation techniques. One of the most effective techniques for new buildings is the installation of radon barriers. The most important parameter determining whether the barrier is adequate to protect against radon is the diffusion coefficient, whose measurement methodology is standardized in ISO/TS 11665¿13:2017. This work applies a previously tested modification of this standard to calculate the radon diffusion coefficient of different materials used as single or multilayer form barriers. Given that there are wasted laminated materials, composed of polymeric materials and aluminium, which are difficult to recycle, a preliminary study of the possible effectiveness of these materials as radon barriers will be carried out using these materials separately or in combination. The materials to be tested are 10-¿m sheets of polyethene (PE) and 15-¿m sheets of aluminium (Al), testing in each case one, two and three layers of each material. In addition, combinations of the two materials, i.e., PE-Al-PE and PE-Al-PE-Al-PE, are also studied. The diffusion coefficients obtained vary around 2¿10-12 m2/s for PE and around 1¿10-13 m2/s in the case of Al. The combination of both materials improved results obtained for single-materials barriers giving a diffusion coefficient between 10-13 and 10-14 m2/s. Radon reductions achieved range from 70 to 87.5% for PE to more than 98% for Al and the materials combinations. The excellent radon shielding capacity of aluminium is observed, which grows with increasing material thickness. Furthermore, it can be stated that the use of multilayer materials of different nature is very effective in reducing the radon concentration reaching an enclosed space and the use of aluminium in some of the layers is essential to achieve a more significant shielding effect.This work is financed by the Spanish Nuclear Safety Council under the project 'Caracterización, exhalación y remediación de Radón en materiales de construcción (EXRADON). The authors would like to thank GDES for their collaboration during the research.Ruvira-Quintana, B.; García-Fayos, B.; Juste Vidal, BJ.; Arnal Arnal, JM.; Verdú Martín, GJ. (2022). Determination of the radon diffusion coefficient of thin polyethene and aluminium foils used as single or multilayer configuration barriers. Radiation Physics and Chemistry. 200:1-5. https://doi.org/10.1016/j.radphyschem.2022.1103291520

Analysis of evaluation instruments on Engineering Degrees

This work presents an analysis that has been done about the assessment tools used by the professors of the Universitat Politécnica de Catalunya to assess the generic competencies introduced in the Bachelor’s Degrees in Engineering. In order to realize this study has been elaborated a survey which has been done anonymously to a sample of the most receptive professors with the educational innovation of the own university. In total there were 80 professors who answered the cited survey, of whom the 26% resulted to be members of the evaluation innovation group the own university, GRAPA. The variables analysis realized using the statistical program SPPS v19 shows that for practically the 49% of the surveyed the rubrics are the most utilized tools to assess the generic competencies integrated with the specific ones, and of those the 60% use them frequently or always. In addition, the results also indicate that there are not significant differences between the GRAPA’s professorship and the remain of the surveyed.Peer Reviewe

Risk factors associated with the development of delirium in general ICU patients. A prospective observational study.

Objective We aimed to analyze risk factors related to the development of delirium, aiming for early intervention in patients with greater risk. Material and methods Observational study, including prospectively collected patients treated in a single general ICU. These were classified into two groups, according to whether they developed delirium or not (screening performed using CAM-ICU tool). Demographics and clinical data were analyzed. Multivariate logistic regression analyses were performed to quantify existing associations. Results 1462 patients were included. 93 developed delirium (incidence: 6.3%). These were older, scored higher on the Clinical Frailty Scale, on the risk scores on admission (SAPS-3 and SOFA), and had a greater number of organ failures (OF). We observed more incidence of delirium in patients who (a) presented more than two OF (20.4%; OR 4.9; CI95%: 2.9–8.2), and (b) were more than 74 years old albeit having <2 OF (8.6%; OR 2.1; CI95%: 1.3–3.5). Patients who developed delirium had longer ICU and hospital length-of-stays and a higher rate of readmission. Conclusions The highest risk observed for developing delirium clustered in patients who presented more than 2 OF and patients over 74 years old. The detection of patients at high risk for developing delirium could imply a change in management and improved quality of care.post-print382 K

Evaluation of methodology PBL done by students

Aquest document es troba a: http://ieeexplore.ieee.org/Xplore/dynhome.jspThis article presents the application of PBL (Project Based Learning) methodology in a subject called Projects within the degree of Industrial Organization (ETSEIATUPC) and includes a detailed feedback from students in terms of their “experiences and feelings” about such implementation. It is, therefore, a real project carried out by students in which they themselves assume responsibilities and, hence, perform an active role in their own learning process always following the guidelines set by the professor, who designs specific activities or recreates scenarios accordingly.Peer ReviewedPostprint (published version

Fast optimized Monte Carlo phase-space generation and dose prediction for low energy x-ray intra-operative radiation therapy

Low energy x-ray intra-operative radiation therapy (IORT) is used mostly for breast cancer treatment with spherical applicators. X-ray IORT treatment delivered during surgery (ex: INTRABEAM (R), Carl Zeiss) can benefit from accurate and fast dose prediction in a patient 3D volume. However, full Monte Carlo (MC) simulations are time-consuming and no commercial treatment planning system (TPS) was available for this treatment delivery technique. Therefore, the aim of this work is to develop a dose computation tool based on MC phase space information, which computes fast and accurate dose distributions for spherical and needle INTRABEAM (R) applicators. First, a database of monoenergetic phase-space (PHSP) files and depth dose profiles (DDPs) in water for each applicator is generated at factory and stored for on-site use. During commissioning of a given INTRABEAM (R) unit, the proposed fast and optimized phase-space (FOPS) generation process creates a phase-space at the exit of the applicator considered, by fitting the energy spectrum of the source to a combination of the monoenergetic precomputed phase-spaces, by means of a genetic algorithm, with simple experimental data of DDPs in water provided by the user. An in-house hybrid MC (HMC) algorithm which takes into account condensed history simulations of photoelectric, Rayleigh and Compton interactions for x-rays up to 1 MeV computes the dose from the optimized phase-space file. The whole process has been validated against radiochromic films in water as well as reference MC simulations performed with pen Easy in heterogeneous phantoms. From the pre-computed monoenergetic PHSP files and DDPs, building the PHSP file optimized to a particular depth-dose curve in water only takes a few minutes in a single core ([email protected] GHz), for all the applicators considered in this work, and this needs to be done only when the x-ray source (XRS) is replaced. Once the phase-space file is ready, the HMC code is able to compute dose distributions within 10 min. For all the applicators, more than 95% of voxels from dose distributions computed with the FOPS+hybrid code agreed within 7%-0.5 mm with both reference MC simulations and measurements. The method proposed has been fully validated and it is now implemented into radiance (GMV SA, Spain), the first commercial IORT TPS

Study of potential capacity as adsorbent of Moringa oleifera substrates for treatment of radon contaminated air in indoor spaces: Preliminary test

[EN] Radon is a radioactive gas known to be a human carcinogenic element that causes lung cancer. The Directive 2013/59/EURATOM establishes action plans for its monitorization and control in water and air specially at workplaces. There are several techniques to reduce the concentration of radon in air mainly based on improving ventilation rates. However, intelligent and energy-efficient buildings are well insulated and have centralized ventilation systems where air is recirculated continuously. This strategy has a negative influence on radon accumulation at indoor spaces. So, ventilation systems should be composed by filters with suitable materials to adsorb radon from indoor air. This work studies the radon adsorption ability of the most used adsorbent (activated carbon) and some not-processed substrates coming from Moringa oleifera, a natural plant with high potential as adsorbent for heavy metals and coagulant in and water treatment. The radon adsorption efficiency of the different solids is analyzed, showing promising results for radionuclide removal from air.García-Fayos, B.; Juste Vidal, BJ.; Sancho, M.; Arnal Arnal, JM.; Noverques-Medina, A.; Verdú Martín, GJ. (2020). Study of potential capacity as adsorbent of Moringa oleifera substrates for treatment of radon contaminated air in indoor spaces: Preliminary test. Radiation Physics and Chemistry. 167:1-3. https://doi.org/10.1016/j.radphyschem.2019.04.012S13167Garcia-Fayos, B., Arnal, J. M., Piris, J., & Sancho, M. (2016). Valorization of Moringa oleifera seed husk as biosorbent: isotherm and kinetics studies to remove cadmium and copper from aqueous solutions. Desalination and Water Treatment, 57(48-49), 23382-23396. doi:10.1080/19443994.2016.1180473García-Tobar, J. (2014). Influencia de las condiciones meteorológicas sobre el nivel de radón a corto plazo en un laboratorio subterráneo. Nova Scientia, 6(12), 78. doi:10.21640/ns.v6i12.25George, A. C. (1984). Passive, Integrated Measurement of Indoor Radon Using Activated Carbon. Health Physics, 46(4), 867-872. doi:10.1097/00004032-198404000-00012Guyot, G., Sherman, M. H., & Walker, I. S. (2018). Smart ventilation energy and indoor air quality performance in residential buildings: A review. Energy and Buildings, 165, 416-430. doi:10.1016/j.enbuild.2017.12.051Karunakara, N., Sudeep Kumara, K., Yashodhara, I., Sahoo, B. K., Gaware, J. J., Sapra, B. K., & Mayya, Y. S. (2015). Evaluation of radon adsorption characteristics of a coconut shell-based activated charcoal system for radon and thoron removal applications. Journal of Environmental Radioactivity, 142, 87-95. doi:10.1016/j.jenvrad.2014.12.01