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The COVID pandemic has touched many aspects of everyone’s life. Education is one of the fields greatly affected by it, as students and teachers were forced to move online and quickly adapt to the online environment. Assessment is a crucial part of education, especially in STEM fields. A gap analysis was performed by expert groups in the frame of an Erasmus+ project looking at the practices of six European countries. Specialists teaching university-grade mathematics in seven European institutions were asked about their perception of gaps in the assessment of students both before (2019) and during (2021) the pandemic. This qualitative study looks at the difference in perception of such gaps after almost one year of online teaching. The analysis of their responses showed that some gaps were present before the pandemic, as well as others that are specific to it. Some gaps, such as the lack of IT infrastructure and the need to adapt materials to an online environment, have been exacerbated by the outbreak.
Vlad Bocanet; Ken Brown; Anne Uukkivi; Filomena Soares; Ana Lopes; Anna Cellmer; Carles Serrat; Cristina Feniser; Florina Serdean; Elena Safiulina; Gerald Kelly; Joanna Cymerman; Igor Kierkosz; Volodymyr Sushch; Marina Latõnina; Oksana Labanova; M. Bruguera; Chara Pantazi; M. Estela. Change in Gap Perception within Current Practices in Assessing Students Learning Mathematics. Sustainability 2021, 13, 4495 .
AMA StyleVlad Bocanet, Ken Brown, Anne Uukkivi, Filomena Soares, Ana Lopes, Anna Cellmer, Carles Serrat, Cristina Feniser, Florina Serdean, Elena Safiulina, Gerald Kelly, Joanna Cymerman, Igor Kierkosz, Volodymyr Sushch, Marina Latõnina, Oksana Labanova, M. Bruguera, Chara Pantazi, M. Estela. Change in Gap Perception within Current Practices in Assessing Students Learning Mathematics. Sustainability. 2021; 13 (8):4495.
Chicago/Turabian StyleVlad Bocanet; Ken Brown; Anne Uukkivi; Filomena Soares; Ana Lopes; Anna Cellmer; Carles Serrat; Cristina Feniser; Florina Serdean; Elena Safiulina; Gerald Kelly; Joanna Cymerman; Igor Kierkosz; Volodymyr Sushch; Marina Latõnina; Oksana Labanova; M. Bruguera; Chara Pantazi; M. Estela. 2021. "Change in Gap Perception within Current Practices in Assessing Students Learning Mathematics." Sustainability 13, no. 8: 4495.
To make periodic inspections of the buildings is useful to quantify the extent to which deficiencies are severe or not, in order to facilitate decision making and prioritize interventions. In previous works by the authors is proposed a scale of gravity of damages in buildings, with the aim of being of widespread and of common use among professionals. This scale is applied through the direct assignment (DA) methodology, based on the generic definitions of each degree. It is demonstrated and characterized the existence of certain level of variability among technicians, when assigning gravity values using DA methodology, due to the fuzzy condition of the attribute to be evaluated. The main goal of this paper is to propose a methodology to assign values of gravity, based on hazard for people of detachments from the façade, by using measurable parameters and mathematical functions. The final objective is to reduce the level of variability among inspectors when assessing the condition state of a building façade. The proposed methodology is named system of evaluation of façades (SEF). The methodology can be also extended to the assessment of other building systems as structures or roofs and other type of infrastructures.
Félix Ruiz; Antonio Aguado; Carles Serrat; Joan R. Casas. Condition assessment of building façades based on hazard to people. Structure and Infrastructure Engineering 2019, 15, 1346 -1365.
AMA StyleFélix Ruiz, Antonio Aguado, Carles Serrat, Joan R. Casas. Condition assessment of building façades based on hazard to people. Structure and Infrastructure Engineering. 2019; 15 (10):1346-1365.
Chicago/Turabian StyleFélix Ruiz; Antonio Aguado; Carles Serrat; Joan R. Casas. 2019. "Condition assessment of building façades based on hazard to people." Structure and Infrastructure Engineering 15, no. 10: 1346-1365.
In this paper authors conduct a case study analysis by implementing the use of UAVs in the data collection within the BRAIN framework for the failures diagnosis of facades. The main goal is to assess the conditions and usefulness of UAVs in the BRAIN protocol by analyzing the goodness of fit to the fundamental requirements that support this inspection methodology. This preliminary qualitative approach allows the authors to investigate the benefits and potential of this high performance technology as a complement or alternative tool to the initial method, which is based on visual inspections supported, as maximum, by high resolution digital camera images. For the study a sample of facades has been selected in Poland. A full equipped UAV has been collecting the images. Finally, full procedure, collected data and positive and negative issues has been assessed under the perspective of the requirements involved in a multiscale BRAIN inspection. Overall scoring conditions has been determined and, as a conclusion, it can be stated that the use of UAVs for technical inspections in a population based predictive approach is, and even more it will be in the future, an interesting complementary tool for the data collection.
Carles Serrat; Anna Cellmer; Anna Banaszek; Vicenç Gibert. Exploring conditions and usefulness of UAVs in the BRAIN Massive Inspections Protocol. Open Engineering 2019, 9, 1 -6.
AMA StyleCarles Serrat, Anna Cellmer, Anna Banaszek, Vicenç Gibert. Exploring conditions and usefulness of UAVs in the BRAIN Massive Inspections Protocol. Open Engineering. 2019; 9 (1):1-6.
Chicago/Turabian StyleCarles Serrat; Anna Cellmer; Anna Banaszek; Vicenç Gibert. 2019. "Exploring conditions and usefulness of UAVs in the BRAIN Massive Inspections Protocol." Open Engineering 9, no. 1: 1-6.
Félix Ruiz; Antonio Aguado; Carles Serrat; Joan R. Casas. Optimal metric for condition rating of existing buildings: is five the right number? Structure and Infrastructure Engineering 2019, 15, 740 -753.
AMA StyleFélix Ruiz, Antonio Aguado, Carles Serrat, Joan R. Casas. Optimal metric for condition rating of existing buildings: is five the right number? Structure and Infrastructure Engineering. 2019; 15 (6):740-753.
Chicago/Turabian StyleFélix Ruiz; Antonio Aguado; Carles Serrat; Joan R. Casas. 2019. "Optimal metric for condition rating of existing buildings: is five the right number?" Structure and Infrastructure Engineering 15, no. 6: 740-753.
Buildings show symptoms and suffer injuries or failures that demand efficient approaches and sustainable solutions in order to maintain or improve their condition. In previous studies, the authors of this paper proposed a network methodology which stores and analyzes information on the degradation of the built environment in different cities, based on a visual inspection methodology for data collection. The demand for accurate information analysis of facades, along with the inspection time for each facade, creates a need for new information collecting techniques. Therefore, this article aims to evaluate technological equipment incorporated in the traditional inspection methods that can work as a complement to achieve better and more advanced results. For this, an experiment was carried out in the city of Brno, Czech Republic, where five building facades in the city center were analyzed in order to qualify and validate a mobile georeferenced scanner, static georeferenced scanner and thermographic camera equipment for potential incorporation into the current inspection method. Quantitative and qualitative analyses are included, together with some of the capabilities and potential uses of these technological resources for an improvement in the network methodology.
L M Acosta; A Torres; Zdenek Krejza; V Gibert; C Serrat. Exploring Technological Alternatives to the Visual Inspection Method in the Built Environment. IOP Conference Series: Earth and Environmental Science 2019, 222, 012027 .
AMA StyleL M Acosta, A Torres, Zdenek Krejza, V Gibert, C Serrat. Exploring Technological Alternatives to the Visual Inspection Method in the Built Environment. IOP Conference Series: Earth and Environmental Science. 2019; 222 (1):012027.
Chicago/Turabian StyleL M Acosta; A Torres; Zdenek Krejza; V Gibert; C Serrat. 2019. "Exploring Technological Alternatives to the Visual Inspection Method in the Built Environment." IOP Conference Series: Earth and Environmental Science 222, no. 1: 012027.
The unavoidable deterioration of the built urban front in the cities has been increasingly generating a huge environmental impact. From this perspective, it is necessary to develop systematized methods that facilitate strategic maintenance of the facades and which study the variables that can potentially play a significant role in the damage occurrence. Therefore it is convenient to implement analytical methodologies to the decision making process on conservation and sustainability of the built urban front with a macro-scale approach. The BRAIN platform (Building Research Analysis and Information Network) is a Multi-scale Predictive System of the Degradation of the Urban Front. By means of periodic inspections, BRAIN allows analyses of damage progression and prediction of the future affectation, based on survival/reliability statistical models. The aim of this paper is to introduce a preliminary study on the implementation of the Urban Laboratory in the city of Brno, Czech Republic. Results of this primary approach have been displayed and discussed.
A Torres; L M Acosta; V Gibert; C Serrat. Implementation of a Multi-scale Predictive System of the Degradation of the Urban Front in Brno, Czech Republic. IOP Conference Series: Earth and Environmental Science 2019, 222, 012029 .
AMA StyleA Torres, L M Acosta, V Gibert, C Serrat. Implementation of a Multi-scale Predictive System of the Degradation of the Urban Front in Brno, Czech Republic. IOP Conference Series: Earth and Environmental Science. 2019; 222 (1):012029.
Chicago/Turabian StyleA Torres; L M Acosta; V Gibert; C Serrat. 2019. "Implementation of a Multi-scale Predictive System of the Degradation of the Urban Front in Brno, Czech Republic." IOP Conference Series: Earth and Environmental Science 222, no. 1: 012029.
It is vital to select the right project bidders, as this affects the success of a project. Although there are numerous methods for assessing bidders, communication is rarely taken into account. This paper discusses the results of a survey on communication key performance indicators (KPIs) and the success of construction projects. Data were collected from 390 construction partners in Spain. The results indicate that the most significant communication KPI is the quality of information: basically, its accuracy and timeliness. In addition, experienced respondents placed less importance on communication flow structures and communication management than did inexperienced respondents. Experienced respondents distrusted new trends and/or management theories and mainly relied on experience. The findings also reveal that the communication flow structure, the communication and information management plan, and the channels of communication are relevant aspects for the success of a project. The results of this research can be used to assess bidders’ communication abilities and systems.
Nuria Forcada; Carles Serrat; Sonia Rodríguez; Rafaela Bortolini. Communication Key Performance Indicators for Selecting Construction Project Bidders. Journal of Management in Engineering 2017, 33, 04017033 .
AMA StyleNuria Forcada, Carles Serrat, Sonia Rodríguez, Rafaela Bortolini. Communication Key Performance Indicators for Selecting Construction Project Bidders. Journal of Management in Engineering. 2017; 33 (6):04017033.
Chicago/Turabian StyleNuria Forcada; Carles Serrat; Sonia Rodríguez; Rafaela Bortolini. 2017. "Communication Key Performance Indicators for Selecting Construction Project Bidders." Journal of Management in Engineering 33, no. 6: 04017033.
We study longevity and usage of medical resources of a sample of individuals aged 65 years or more who are covered by a private insurance policy. A longitudinal analysis is presented, where the annual cumulative number of medical coverage requests by each subject characterizes insurance intensity of care until death. We confirm that there is a significant correlation between the longitudinal data on usage level and the survival time processes. We obtain dynamic estimations of event probabilities and we exploit the potential of joint models for personalized survival curve adjustment.
Xavier Piulachs; Ramon Alemany; Montserrat Guillén; Carles Serrat. Joint Modeling of Health Care Usage and Longevity Uncertainty for an Insurance Portfolio. Advances in Intelligent Systems and Computing 2015, 289 -297.
AMA StyleXavier Piulachs, Ramon Alemany, Montserrat Guillén, Carles Serrat. Joint Modeling of Health Care Usage and Longevity Uncertainty for an Insurance Portfolio. Advances in Intelligent Systems and Computing. 2015; ():289-297.
Chicago/Turabian StyleXavier Piulachs; Ramon Alemany; Montserrat Guillén; Carles Serrat. 2015. "Joint Modeling of Health Care Usage and Longevity Uncertainty for an Insurance Portfolio." Advances in Intelligent Systems and Computing , no. : 289-297.
Carles Serrat; Montserrat Rue; Carmen Armero; Xavier Piulachs; Hèctor Perpiñán; Anabel Forte; Alvaro Paez; Guadalupe Gómez. Frequentist and Bayesian approaches for a joint model for prostate cancer risk and longitudinal prostate-specific antigen data. Journal of Applied Statistics 2015, 42, 1223 -1239.
AMA StyleCarles Serrat, Montserrat Rue, Carmen Armero, Xavier Piulachs, Hèctor Perpiñán, Anabel Forte, Alvaro Paez, Guadalupe Gómez. Frequentist and Bayesian approaches for a joint model for prostate cancer risk and longitudinal prostate-specific antigen data. Journal of Applied Statistics. 2015; 42 (6):1223-1239.
Chicago/Turabian StyleCarles Serrat; Montserrat Rue; Carmen Armero; Xavier Piulachs; Hèctor Perpiñán; Anabel Forte; Alvaro Paez; Guadalupe Gómez. 2015. "Frequentist and Bayesian approaches for a joint model for prostate cancer risk and longitudinal prostate-specific antigen data." Journal of Applied Statistics 42, no. 6: 1223-1239.
We consider the conditional estimation of the survival function of the time T2 to a second event as a function of the time T1 to a first event when there is a censoring mechanism acting on their sum T1+T2. The problem has been motivated by a treatment interruption study aimed at improving the quality of life of HIV-infected patients. We base the analysis on the survival function of T2 given that T1∈I, where I represents a period of scientific interest (1 trimester, 1 year, 2 years, etc.) and propose a non-parametric estimator for the survival function of T2 given that T1∈I, which takes into account both the selection bias and the heterogeneity due to the dependent censoring. The proposed estimator for the survival function uses the risk group of T2 conditioned on the categories of T1 and corrects for the dependent censoring using weights defined by the observed values of T1. The estimator, properly normalized, converges weakly to a zero-mean Gaussian process. We estimate the variance of the limiting process via a bootstrap methodology. Properties of the proposed estimator are illustrated by an extensive simulation study. The motivating data set is analysed by means of this new methodology.
Guadalupe Gomez; Carles Serrat; Carles Serrat Piè. Correcting the bias due to dependent censoring of the survival estimator by conditioning. Statistics 2012, 48, 295 -314.
AMA StyleGuadalupe Gomez, Carles Serrat, Carles Serrat Piè. Correcting the bias due to dependent censoring of the survival estimator by conditioning. Statistics. 2012; 48 (2):295-314.
Chicago/Turabian StyleGuadalupe Gomez; Carles Serrat; Carles Serrat Piè. 2012. "Correcting the bias due to dependent censoring of the survival estimator by conditioning." Statistics 48, no. 2: 295-314.
This chapter discusses and illustrates some potential applications of discrete-event simulation (DES) techniques in structural reliability and availability analysis, emphasizing the convenience of using probabilistic approaches in modern building and civil engineering practices. After reviewing existing literature on the topic, some advantages of probabilistic techniques over analytical ones are highlighted. Then, we introduce a general framework for performing structural reliability and availability analysis through DES. Our methodology proposes the use of statistical distributions and techniques – such as survival analysis – to model component-level reliability. Then, using failure- and repair-time distributions and information about the structural logical topology (which allows determination of the structural state from their components’ state), structural reliability, and availability information can be inferred. Two numerical examples illustrate some potential applications of the proposed methodology to achieving more reliable and structural designs. Finally, an alternative approach to model uncertainty at component level is also introduced as ongoing work. This new approach is based on the use of fuzzy rule-based systems and it allows the introduction of experts’ opinions and evaluations in our methodology.
Angel A. Juan; Albert Ferrer; Carles Serrat; Javier Faulin; Gleb Beliakov; Joshua Hester; Carles Serrat Piè. Potential Applications of Discrete-event Simulation and Fuzzy Rule-based Systems to Structural Reliability and Availability. Springer Series in Reliability Engineering 2010, 199 -214.
AMA StyleAngel A. Juan, Albert Ferrer, Carles Serrat, Javier Faulin, Gleb Beliakov, Joshua Hester, Carles Serrat Piè. Potential Applications of Discrete-event Simulation and Fuzzy Rule-based Systems to Structural Reliability and Availability. Springer Series in Reliability Engineering. 2010; ():199-214.
Chicago/Turabian StyleAngel A. Juan; Albert Ferrer; Carles Serrat; Javier Faulin; Gleb Beliakov; Joshua Hester; Carles Serrat Piè. 2010. "Potential Applications of Discrete-event Simulation and Fuzzy Rule-based Systems to Structural Reliability and Availability." Springer Series in Reliability Engineering , no. : 199-214.
In this paper, we propose the use of discrete-event simulation (DES) as an efficient methodology to obtain estimates of both survival and availability functions in time-dependent real systems—such as telecommunication networks or distributed computer systems. We discuss the use of DES in reliability and availability studies, not only as an alternative to the use of analytical and probabilistic methods, but also as a complementary way to: (i) achieve a better understanding of the system internal behavior and (ii) find out the relevance of each component under reliability/availability considerations. Specifically, this paper describes a general methodology and two DES algorithms, called SAEDES, which can be used to analyze a wide range of time-dependent complex systems, including those presenting multiple states, dependencies among failure/repair times or non-perfect maintenance policies. These algorithms can provide valuable information, specially during the design stages, where different scenarios can be compared in order to select a system design offering adequate reliability and availability levels. Two case studies are discussed, using a C/C++ implementation of the SAEDES algorithms, to show some potential applications of our approach.
Javier Faulin; Angel Juan; Carles Serrat; Vicente Bargueño. Predicting availability functions in time-dependent complex systems with SAEDES simulation algorithms. Reliability Engineering & System Safety 2008, 93, 1761 -1771.
AMA StyleJavier Faulin, Angel Juan, Carles Serrat, Vicente Bargueño. Predicting availability functions in time-dependent complex systems with SAEDES simulation algorithms. Reliability Engineering & System Safety. 2008; 93 (11):1761-1771.
Chicago/Turabian StyleJavier Faulin; Angel Juan; Carles Serrat; Vicente Bargueño. 2008. "Predicting availability functions in time-dependent complex systems with SAEDES simulation algorithms." Reliability Engineering & System Safety 93, no. 11: 1761-1771.
In this article we present a review of the state of the art in mathematical e-learning and some personal experiences on this area developed during the last eleven years at the Open University of Catalonia (UOC), a completely online university located in Spain. The article discusses important aspects related to online mathematics courses offered in higher education programs, including: benefits and challenges, universities offering this type of education, methodological considerations, emergent technologies, learning projects and environments, etc. Also, key aspects of the UOC mathematical e-learning model and its historical evolution are described and analysed. Special attention is paid to mathematical curricula in computer sciences degrees, where a lot of work needs to be done in order to adapt mathematics courses to the continuously changing educational necessities of students. A curricula design proposal, based on a top-down approach, is presented as a best practice. Finally, some trends and future perspectives on the subject are suggested.
Angel A. Juan; A. Huertas; C. Steegmann; César Córcoles; C. Serrat; Carles Serrat Piè. Mathematical e-learning: state of the art and experiences at the Open University of Catalonia. International Journal of Mathematical Education in Science and Technology 2008, 39, 455 -471.
AMA StyleAngel A. Juan, A. Huertas, C. Steegmann, César Córcoles, C. Serrat, Carles Serrat Piè. Mathematical e-learning: state of the art and experiences at the Open University of Catalonia. International Journal of Mathematical Education in Science and Technology. 2008; 39 (4):455-471.
Chicago/Turabian StyleAngel A. Juan; A. Huertas; C. Steegmann; César Córcoles; C. Serrat; Carles Serrat Piè. 2008. "Mathematical e-learning: state of the art and experiences at the Open University of Catalonia." International Journal of Mathematical Education in Science and Technology 39, no. 4: 455-471.
Survival analysis statistics have been used to estimate shelf life of foods based on consumers’ acceptance or rejection of samples with different storage times. The interval censored nature of the data does not allow regular methods to estimate the number of necessary consumers (N) for these studies. The objective of the present work was to use simulation studies to estimate N considering the error in the estimation, statistical significance and statistical power. Based on previous studies a Weibull model was assumed for the lifetime distribution with a shape parameter σ between 0.17 and 0.71. Simulations were calculated supposing shelf-life values in the middle range of an adimensional time scale. Graphs to estimate N under different scenarios are presented. Considering the average σ, an alpha value (Type I error) of 5%, a beta value (Type II error) of 20%, the shelf life to be in the middle of the studied time range, and a difference between the true shelf life and the estimated shelf life of 0.5 on a 0–6 time scale, gave an N value of 120 consumers for this particular set of parameters.
Guillermo Hough; M. Luz Calle; Carles Serrat; Ana Curia; Carles Serrat Piè. Number of consumers necessary for shelf life estimations based on survival analysis statistics. Food Quality and Preference 2007, 18, 771 -775.
AMA StyleGuillermo Hough, M. Luz Calle, Carles Serrat, Ana Curia, Carles Serrat Piè. Number of consumers necessary for shelf life estimations based on survival analysis statistics. Food Quality and Preference. 2007; 18 (5):771-775.
Chicago/Turabian StyleGuillermo Hough; M. Luz Calle; Carles Serrat; Ana Curia; Carles Serrat Piè. 2007. "Number of consumers necessary for shelf life estimations based on survival analysis statistics." Food Quality and Preference 18, no. 5: 771-775.
Lorena V. Garitta; Carles Serrat; Guillermo E. Hough; Ana V. Curia; Carles Serrat Piè. Determination of Optimum Concentrations of a Food Ingredient Using Survival Analysis Statistics. Journal of Food Science 2006, 71, S526 -S532.
AMA StyleLorena V. Garitta, Carles Serrat, Guillermo E. Hough, Ana V. Curia, Carles Serrat Piè. Determination of Optimum Concentrations of a Food Ingredient Using Survival Analysis Statistics. Journal of Food Science. 2006; 71 (7):S526-S532.
Chicago/Turabian StyleLorena V. Garitta; Carles Serrat; Guillermo E. Hough; Ana V. Curia; Carles Serrat Piè. 2006. "Determination of Optimum Concentrations of a Food Ingredient Using Survival Analysis Statistics." Journal of Food Science 71, no. 7: S526-S532.
Javier Faulin; Angel A. Juan; C. Serrat; Vicente Bargueno; Carles Serrat Piè. SAEDES++: Determining Complex System Availability Via Simulation. Proceedings of the Winter Simulation Conference, 2005. 2006, 1 .
AMA StyleJavier Faulin, Angel A. Juan, C. Serrat, Vicente Bargueno, Carles Serrat Piè. SAEDES++: Determining Complex System Availability Via Simulation. Proceedings of the Winter Simulation Conference, 2005.. 2006; ():1.
Chicago/Turabian StyleJavier Faulin; Angel A. Juan; C. Serrat; Vicente Bargueno; Carles Serrat Piè. 2006. "SAEDES++: Determining Complex System Availability Via Simulation." Proceedings of the Winter Simulation Conference, 2005. , no. : 1.