872 research outputs found

    Approaching conformality in non-Abelian gauge theories

    Get PDF

    Approaching conformality in non-Abelian gauge theories

    Get PDF

    Approaching conformality in non-Abelian gauge theories

    Get PDF

    Ensemble learning for electricity consumption forecasting in office buildings

    Get PDF
    This paper presents three ensemble learning models for short term load forecasting. Machine learning has evolved quickly in recent years, leading to novel and advanced models that are improving the forecasting results in multiple fields. However, in highly dynamic fields such as power and energy systems, dealing with the fast acquisition of large amounts of data from multiple data sources and taking advantage from the correlation between the multiple available variables is a challenging task, for which current models are not prepared. Ensemble learning is bringing promising results in this sense, as, by combining the results and use of multiple learners, is able to find new ways for current learning models to be used and optimized. In this paper three ensemble learning models are developed and the respective results compared: gradient boosted regression trees, random forests and an adaptation of Adaboost. Results for electricity consumption forecasting in hour-ahead are presented using a case-study based on real data from an office building. Results show that the adapted Adaboost model outperforms the reference models for hour-ahead load forecasting.This work has been developed under the SPET project - PTDC/EEI-EEE/29165/2017 and has received funding from UID/EEA/00760/2019, funded by FEDER Funds through COMPETE andby National Funds through FCTinfo:eu-repo/semantics/publishedVersio

    Let's Talk About Stereochemistry for a Moment: a Home Experiment Conducted with College Students in Social Isolation

    Get PDF
    Due to COVID-19, we are adjusting to a new educational environment while also being socially isolated. By combining previously established ways of remote education with video conferences, the world is creating a new sector termed techno-pedagogy. The concept of stereochemistry in Organic Chemistry is frequently difficult to understand even in classroom teaching. Plane-polarized light rotation is difficult to describe because it needs a high level of abstraction in the mental exercise. As a result, we propose in this work that technology be developed to teach stereochemistry remotely. As a result, we prepared a training video that shows college students how to execute a hand-made stereochemistry experiment. Lecturers, undergraduates, and graduate students all gave the video great scores

    Assessment of satisfaction and Quality of Life using self - reported questionnaires after urethroplasty : a prospective analysis

    Get PDF
    Objectives: To assess patient satisfaction and quality of life after urethroplasty using two different self-reported outcome measures and to compare it with objective clinical data. Materials and Methods: We prospectively collected data from 35 consecutive patients who underwent urethroplasty from January 2013 to September 2014. Patient demographics, International Prostate Symptom Score (IPSS), quality of life score, urethral stricture surgery patient-reported outcome measure (USS-PROM), maximum flow rate (Qmax) and post-void residual urine were collected before, two and eight months after surgery. Failure occurred when any postoperative instrumentation was performed. General estimation equation was used to compare the results and linear regression analysis to correlate both questionnaires with objective data. Results: Mean age was 61 years. Urethroplasties were equally divided between anastomotic and buccal mucosa grafts and 19 patients (59.3%) had a previous urethral procedure. Overall success rate was 87.5%. IPSS improved from a mean 19 at baseline to 5.32 at 8 months (p <0.001). The mean USS-PROM score also improved from 13.21 preoperatively to 3.36 after surgery (p <0.001) and 84.3% of patients were satisfied or very satisfied with surgical results. Mean Qmax increased from 4.64mL/s to 11mL/s (p <0.001). Strong negative correlation was found respectively between flow rate and USS-PROM (r=-0.531, p <0.001) and with IPSS (r=-0.512, p <0.001). Conclusions: Significant improvements in urinary symptoms and in quality of life are expected after urethroplasty and they are correlated with objective measures

    Current state of antimicrobial stewardship and organ transplantation in Spain

    Get PDF
    Introduction Solid-organ transplantation (SOT) remains the best therapeutic option for end-stage organ disease. Regrettably, SOT recipients are disproportionately affected by nosocomial infections produced by multidrug-resistant (MDR) microorganisms and antimicrobial adverse events. Both have a negative impact on the patient®s outcome. Methods Description of data concerning the antimicrobial stewardship program (ASP) in SOT recipients of the University Hospital “12 de Octubre”, and review of other Spanish ASPs. Results From May 2017 to December 2021, the ASP issued 2.785 recommendations. Approximately, 4.9% were aimed at improving the antimicrobial treatment administered to SOT recipients. Treatment discontinuation or change to a better therapeutic regimen was recommended in 51.8% and 26.3% of cases, respectively. The acceptance rate of the recommendations was close to 92%. Between June 2015 and March 2016, a quasi-experimental study consisting of a joint ASP and hospital-acquired infection control (HAIC) initiative, which included kidney transplant recipients, reported a significant reduction in the consumption of meropenem, vancomycin and ciprofloxacin, and a reduction in the incidence of global bacterial infections, upper urinary tract infections, and cystitis. Although Spain has several robust regional ASPs (e.g., VINCat and PIRASOA), data specifically concerning SOT patients is lacking. Conclusion ASP coupled with HAIC programs have proven to be effective in SOT, and should be implemented in centers that perform transplantation. Since data is scarce, Spanish centers which have ASP should report their experience in SOT. Understanding the efficacy and safety of the Spanish ASP®s intervention in the SOT population is essential and deserves further study

    Experimental and Numerical Investigation of Post-Flutter Limit Cycle Oscillations on a Cantilevered Flat Plate

    Get PDF
    Futuristic aircraft designs and novel aircraft such as High Altitude Long Endurance (HALE) involve a higher level of structural flexibility than in conventional aircraft. Even at present, the trends in the aviation industry are to increase wing length (to reduce induced drag) and maxi- mize use of composites, which lead to increased structural flexibility. This necessitates a rethink of conventional (linear) aeroelastic analysis, since the increased flexibility results in coupling between the flight dynamic and aeroelastic dynamics, and consequently, limit-cycle oscillations of the structure. In this paper, a new three-dimensional low-order model for unsteady aerody- namics that accounts for large oscillation amplitudes and nonplanar wakes is developed. An experiment with a cantilevered flat plate at low Reynolds number is set up and used to validate the low-order model, as well as to study post-flutter limit-cycle oscillations. Results from the low-order model are promising, but show that aerodynamic nonlinearities such as flow sepa- ration and leading-edge vortex shedding must also be modeled in order to predict all possible limit-cycle oscillations of the aeroelastic system

    Tracking young talented swimmers: follow-up of performance and its biomechanical determinant factors

    Get PDF
    The aims of study were to follow-up and analyze the stability of young talent swimmers’ performance and its determinant determinantsfactors (i.e. anthropometrics, kinematics, hydrodynamics and efficiency) during a competitive season. The aim of this study was to assess the anthropometric, kinematic, hydrodynamic and efficiency stability of young swimmers’ performance during a competitive season. Thirty three (15 boys and 18 girls) young swimmers (overall: 11.81 ± 0.75 years old and Tanner stages 1-2 by self-evaluation) were evaluated. Performance, anthropometrics, kinematics, hydrodynamics and efficiency variables were assessed in three time points during a competitive season. Performance had a significant improvement during the season (moderate-high stability). In the anthropometrics domain all variables increased with significant differences between time points (high-very high stability). In the kinematics domain, stroke length and swimming velocity showed significant differences, although stroke frequency and speed fluctuation did not (low-moderate stability). Hydrodynamics did not present significant differences along the season (low-moderate stability). Efficiency variables did present significant variations (but with low stability). Young swimmers’ performance improved during the competitive season, and it seems that anthropometrical variables were the most determinant to this enhancement

    Tracking young talented swimmers: follow-up of performance and its biomechanical determinant factors

    Get PDF
    The aim of the study was to follow-up the stability of young talented swimmers' performance and its biomechanical determinant factors (i.e., anthropometrics, kinematics, hydrodynamics and efficiency) during a competitive season. Thirty three (15 boys and 18 girls) young swimmers (overall: 11.81 ± 0.75 years old and Tanner stages 1-2 by self-evaluation) were evaluated. Performance, anthropometrics, hydrodynamics, kinematics and efficiency variables were assessed at three moments during a competitive season. Performance had a significant improvement (with minimum effect size) and a moderate-very high stability throughout the season. In the anthropometrics domain all variables increased significantly (ranging from without to minimum effect size) between moments and had a moderate-very high stability. Hydrodynamics presented no variations between all moments and had a low-very high stability throughout the season. In the kinematics domain, there were no variations between moment one and three, except for an increase in stroke frequency (without size effect). Speed fluctuation remained constant, with no significant variations. All kinematic variables had a low-very high stability. Efficiency variables did not present variations between moment one and three and had a low-moderate stability. Overall, young swimmers showed a minimum improvement in performance and in anthropometric factors; and a moderate stability of performance and its determinant factors (i.e., anthropometrics, hydrodynamics, kinematics and efficiency) during the competitive season.info:eu-repo/semantics/publishedVersio
    • 

    corecore