Carlos J. Hellín

Dr. Carlos J. Hellín

orcid

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
24 September 2023 in Sustainability
Verified
Journal Article
Open access
PDF file
CHCarlos J. Hellín
Carlos J. Hellín
FCFrancisco Calles-Esteban
Francisco Calles-Esteban
AVAdrián Valledor
Adrián Valledor
JGJosé Gómez-Pulido
José Gómez-Pulido
SALVADOR OTON TORTOSASALVADOR OTON TORTOSA
SALVADOR OTON TORTOSA
Abdelhamid TayebiAbdelhamid Tayebi
Abdelhamid Tayebi
Gamification is a viable strategy used to enhance motivation and engagement in programming classes among students. However, automated evaluation capabilities, which are crucial for giving students fast and correct feedback, are frequently lacking in currently available gamification technologies. This study proposes a novel web-based application that combines automated programming assessment features with gamification concepts; the aim is to provide students taking a programming course with an engaging learning environment. A survey conducted with 215 undergraduate students assessed how the tool affected the motivation and engagement of students. The findings show that the tool had a beneficial impact on students’ willingness to participate in class, study, increase their self-confidence, engage in healthy competition with peers, and learn from their mistakes. The qualitative feedback that students offered regarding the features of the tool that they liked best is also covered in the study. This paper contributes to the field of programming education by presenting a detailed gamified tool, incorporating automated evaluation and gamification in a web-based platform.

18 April 2024 in Applied Sciences
Verified
Journal Article
Open access
PDF file
CHCarlos J. Hellín
Carlos J. Hellín
ARAlvaro Antonio Olmedo Rodriguez
Alvaro Antonio Olmedo Rodriguez
AVAdrián Valledor
Adrián Valledor
JGJosé Gómez-Pulido
José Gómez-Pulido
MLMiguel López-Benítez
Miguel López-Benítez
Abdelhamid TayebiAbdelhamid Tayebi
Abdelhamid Tayebi
The field of image analysis with artificial intelligence has grown exponentially thanks to the development of neural networks. One of its most promising areas is medical diagnosis through lung X-rays, which are crucial for diseases like pneumonia, which can be mistaken for other conditions. Despite medical expertise, precise diagnosis is challenging, and this is where well-trained algorithms can assist. However, working with medical images presents challenges, especially when datasets are limited and unbalanced. Strategies to balance these classes have been explored, but understanding their local impact and how they affect model evaluation is still lacking. This work aims to analyze how a class imbalance in a dataset can significantly influence the informativeness of metrics used to evaluate predictions. It demonstrates that class separation in a dataset impacts trained models and is a strategy deserving more attention in future research. To achieve these goals, classification models using artificial and deep neural networks implemented in the R environment are developed. These models are trained using a set of publicly available images related to lung pathologies. All results are validated using metrics obtained from the confusion matrix to verify the impact of data imbalance on the performance of medical diagnostic models. The results raise questions about the procedures used to group classes in many studies, aiming to achieve class balance in imbalanced data and open new avenues for future research to investigate the impact of class separation in datasets with clinical pathologies.

22 February 2023 in Sensors
Verified
Journal Article
Open access
PDF file
MBMarcos Barranquero
Marcos Barranquero
ARAlvaro Antonio Olmedo Rodriguez
Alvaro Antonio Olmedo Rodriguez
JGJosé Gómez-Pulido
José Gómez-Pulido
Abdelhamid TayebiAbdelhamid Tayebi
Abdelhamid Tayebi
CHCarlos J. Hellín
Carlos J. Hellín
FAFrancisco Saez De Adana
Francisco Saez De Adana
This paper presents the implementation of an automatic method for the reconstruction of 3D building maps. The core innovation of the proposed method is the supplementation of OpenStreetMap data with LiDAR data to reconstruct 3D urban environments automatically. The only input of the method is the area that needs to be reconstructed, defined by the enclosing points in terms of the latitude and longitude. First, area data are requested in OpenStreetMap format. However, there are certain buildings and geometries that are not fully received in OpenStreetMap files, such as information on roof types or the heights of buildings. To complete the information that is missing in the OpenStreetMap data, LiDAR data are read directly and analyzed using a convolutional neural network. The proposed approach shows that a model can be obtained with only a few samples of roof images from an urban area in Spain, and is capable of inferring roofs in other urban areas of Spain as well as other countries that were not used to train the model. The results allow us to identify a mean of 75.57% for height data and a mean of 38.81% for roof data. The finally inferred data are added to the 3D urban model, resulting in detailed and accurate 3D building maps. This work shows that the neural network is able to detect buildings that are not present in OpenStreetMap for which in LiDAR data are available. In future work, it would be interesting to compare the results of the proposed method with other approaches for generating 3D models from OSM and LiDAR data, such as point cloud segmentation or voxel-based approaches. Another area for future research could be the use of data augmentation techniques to increase the size and robustness of the training dataset.

3 August 2023 in Sustainability
Verified
Journal Article
Open access
PDF file
AVAdrián Valledor
Adrián Valledor
ARAlvaro Antonio Olmedo Rodriguez
Alvaro Antonio Olmedo Rodriguez
CHCarlos J. Hellín
Carlos J. Hellín
Abdelhamid TayebiAbdelhamid Tayebi
Abdelhamid Tayebi
SALVADOR OTON TORTOSASALVADOR OTON TORTOSA
SALVADOR OTON TORTOSA
JGJosé Gómez-Pulido
José Gómez-Pulido
This paper proposes a study of the methodologies used to teach English as a second language through computer applications. It reviews the different methodologies used in language teaching in order to contrast them with different fundamental approaches. It examines the applications used for teaching English online, especially those in line with personalised learning environments and learner-centred autonomy. The use of a mixed methodology is reported, allowing the selection of papers from both a traditional systematic review and the search engine elicit.org. Finally, it is concluded that Blended Learning is the most appropriate method, highlighting that current applications are mainly based on the Audio-Lingual method, which limits their practical use in wider contexts. Further research is needed on software applications that prioritise personalised learning environments with learner-centred autonomy, incorporating technologies based on Blended Learning and artificial intelligence (AI). To this end, it is proposed in the future to develop an application using Automatic Speech Recognition (ASR), Text To Speech (TTS), Natural Language Understanding (NLU) and Dialog Management (DM) algorithms, focusing on the above and simulating the capabilities of a teacher. This may lead to innovations in the development of software applications capable of integrating different methods, teaching modalities and learning methods.

20 April 2024 in Applied Sciences
Verified
Journal Article
Open access
PDF file
FCFrancisco Calles-Esteban
Francisco Calles-Esteban
CHCarlos J. Hellín
Carlos J. Hellín
Abdelhamid TayebiAbdelhamid Tayebi
Abdelhamid Tayebi
HXHanli Liu Xiao
Hanli Liu Xiao
MLMiguel López-Benítez
Miguel López-Benítez
JGJosé Gómez-Pulido
José Gómez-Pulido
In the realm of programming education, enhancing student commitment is pivotal for both academic success and practical application. Traditional methodologies often fall short in catering to the evolving needs of today’s learners. Addressing this gap, this paper introduces a web-based gamified tool designed to transform the pedagogical approach in programming courses. The study’s theoretical contribution lies in its exploration of gamification as a strategy to augment student commitment, bridging the divide between conventional teaching and contemporary learning needs. From a practical standpoint, empirical data encompassing performance metrics, dropout rates, and student feedback demonstrate the tool’s significant positive impact. Notably, students exhibited improved pass rates and reduced dropout tendencies, underscoring the tool’s practical efficacy. Furthermore, feedback highlighted the tool’s usability and the enhanced satisfaction derived from its engagement. Aligned with the existing literature, the findings advocate for the broader adoption of gamification in programming education. This research substantiates the potential of gamification as both a theoretical model and a practical strategy, enriching the discourse on modern programming education.

28 March 2024 in Sensors
Verified
Journal Article
Open access
PDF file
FCFrancisco Calles-Esteban
Francisco Calles-Esteban
ARAlvaro Antonio Olmedo Rodriguez
Alvaro Antonio Olmedo Rodriguez
CHCarlos J. Hellín
Carlos J. Hellín
AVAdrián Valledor
Adrián Valledor
JGJosé Gómez-Pulido
José Gómez-Pulido
Abdelhamid TayebiAbdelhamid Tayebi
Abdelhamid Tayebi
The precise placement of antennas is essential to ensure effective coverage, service quality, and network capacity in wireless communications, particularly given the exponential growth of mobile connectivity. The antenna positioning problem (APP) has evolved from theoretical approaches to practical solutions employing advanced algorithms, such as evolutionary algorithms. This study focuses on developing innovative web tools harnessing genetic algorithms to optimize antenna positioning, starting from propagation loss calculations. To achieve this, seven empirical models were reviewed and integrated into an antenna positioning web tool. Results demonstrate that, with minimal configuration and careful model selection, a detailed analysis of antenna positioning in any area is feasible. The tool was developed using Java 17 and TypeScript 5.1.6, utilizing the JMetal framework to apply genetic algorithms, and features a React-based web interface facilitating application integration. For future research, consideration is given to implementing a server capable of analyzing the environment based on specific area selection, thereby enhancing the precision and objectivity of antenna positioning analysis.