NÉSTOR DIEGO RIVERA

Dr. NÉSTOR DIEGO RIVERA

Transportation Engineering Research Group GIIT, Politecnica Salesiana University, Cuenca, Azuay, Ecuador
orcid

Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

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

Representative Publications

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23 September 2021 in Sensors
Verified
Journal Article
Open access
PDF file
NÉSTOR DIEGO RIVERANÉSTOR DIEGO RIVERA
NÉSTOR DIEGO RIVERA
JMJosé Luis Muñoz-Sanz
José Luis Muñoz-Sanz
BABlanca Arenas-Ramírez
Blanca Arenas-Ramírez
This article proposes a methodology for the estimation of emissions in real driving conditions, based on board diagnostics data and machine learning, since it has been detected that there are no models for estimating pollutants without large measurement campaigns. For this purpose, driving data are obtained by means of a data logger and emissions through a portable emissions measurement system in a real driving emissions test. The data obtained are used to train artificial neural networks that estimate emissions, having previously estimated the relative importance of variables through random forest techniques. Then, by the application of the K-means algorithm, labels are obtained to implement a classification tree and thereby determine the selected gear by the driver. These models were loaded with a data set generated covering 1218.19 km of driving. The results generated were compared to the ones obtained by applying the international vehicle emissions model and with the results of the real driving emissions test, showing evidence of similar results. The main contribution of this article is that the generated model is stronger in different traffic conditions and presents good results at the speed interval with small differences at low average driving speeds because more than half of the vehicle’s trip occurs in urban areas, in completely random driving conditions. These results can be useful for the estimation of emission factors with potential application in vehicular homologation processes and the estimation of vehicular emission inventories.

15 June 2024 in Sensors
Verified
Journal Article
Open access
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Juan José Molina-CampoverdeJuan José Molina-Campoverde
Juan José Molina-Campoverde
NÉSTOR DIEGO RIVERANÉSTOR DIEGO RIVERA
NÉSTOR DIEGO RIVERA
PMPaúl Molina-Campoverde
Paúl Molina-Campoverde
Andrea Karina BermeoAndrea Karina Bermeo
Andrea Karina Bermeo
This study introduces an innovative algorithm for classifying transportation modes. It categorizes modes such as walking, biking, tram, bus, taxi, and private vehicles based on data collected through sensors embedded in smartphones. The data include date, time, latitude, longitude, altitude, and speed, gathered using a mobile application specifically designed for this project. These data were collected through the smartphone’s GPS to enhance the accuracy of the analysis. The stopping times of each transport mode, as well as the distance traveled and average speed, are analyzed to identify patterns and distinctive features. Conducted in Cuenca, Ecuador, the study aims to develop and validate an algorithm to enhance urban planning. It extracts significant features from mobility patterns, including speed, acceleration, and over-acceleration, and applies longitudinal dynamics to train the classification model. The classification algorithm relies on a decision tree model, achieving a high accuracy of 94.6% in validation and 94.9% in testing, demonstrating the effectiveness of the proposed approach. Additionally, the precision metric of 0.8938 signifies the model’s ability to make correct positive predictions, with nearly 90% of positive instances correctly identified. Furthermore, the recall metric at 0.83084 highlights the model’s capability to identify real positive instances within the dataset, capturing over 80% of positive instances. The calculated F1-score of 0.86117 indicates a harmonious balance between precision and recall, showcasing the models robust and well-rounded performance in classifying transport modes effectively. The study discusses the potential applications of this method in urban planning, transport management, public transport route optimization, and urban traffic monitoring. This research represents a preliminary stage in generating an origin–destination (OD) matrix to better understand how people move within the city.

8 November 2023 in IEEE Access
Verified
Journal Article
Open access
MVMary Vergara
Mary Vergara
LRLeo Thomas Ramos
Leo Thomas Ramos
NÉSTOR DIEGO RIVERANÉSTOR DIEGO RIVERA
NÉSTOR DIEGO RIVERA
FRfrancklinr Rivas
francklinr Rivas
This paper introduces EngineFaultDB, a novel dataset capturing the intricacies of automotive engine diagnostics. Centered around the widely represented C14NE spark ignition engine, data was collected under controlled laboratory conditions, simulating various operational states, including normal and specific fault scenarios. Utilizing tools such as an NGA 6000 gas analyzer and a USB 6008 data acquisition card from National Instruments, we were able to monitor and capture a comprehensive range of engine parameters, from throttle position and fuel consumption to exhaust gas emissions. Our dataset, comprising 55,999 meticulously curated entries across 14 distinct variables, provides a holistic picture of engine behavior, making it an invaluable resource for automotive researchers and practitioners. For evaluation, several classifiers, including logistic regression, decision trees, random forests, support vector machines, k-nearest neighbors, and a feed-forward neural network, were trained on this dataset. Their performance, under standard configurations and a simple neural network architecture, offers foundational benchmarks for future explorations. Results underscore the dataset’s potential in fostering advanced diagnostic algorithms. As a testament to our commitment to open research, EngineFaultDB is freely available for academic use. Future work involves expanding the dataset’s diversity, exploring deeper neural architectures, and integrating real-world automotive conditions.

5 April 2024 in Sensors
Verified
Journal Article
Open access
PDF file
NÉSTOR DIEGO RIVERANÉSTOR DIEGO RIVERA
NÉSTOR DIEGO RIVERA
BABlanca Arenas-Ramírez
Blanca Arenas-Ramírez
JSJosé Luis Muñoz Sanz
José Luis Muñoz Sanz
EJEdisson Jiménez
Edisson Jiménez
This paper focuses on the emissions of the three most sold categories of light vehicles: sedans, SUVs, and pickups. The research is carried out through an innovative methodology based on GPS and machine learning in real driving conditions. For this purpose, driving data from the three best-selling vehicles in Ecuador are acquired using a data logger with GPS included, and emissions are measured using a PEMS in six RDE tests with two standardized routes for each vehicle. The data obtained on Route 1 are used to estimate the gears used during driving using the K-means algorithm and classification trees. Then, the relative importance of driving variables is estimated using random forest techniques, followed by the training of ANNs to estimate CO2, CO, NOX, and HC. The data generated on Route 2 are used to validate the obtained ANNs. These models are fed with a dataset generated from 324, 300, and 316 km of random driving for each type of vehicle. The results of the model were compared with the IVE model and an OBD-based model, showing similar results without the need to mount the PEMS on the vehicles for long test drives. The generated model is robust to different traffic conditions as a result of its training and validation using a large amount of data obtained under completely random driving conditions.

1 January 2022 in Materials Today: Proceedings
Verified
Journal Article
Closed access
PCPaúl Andrés Molina Campoverde
Paúl Andrés Molina Campoverde
NÉSTOR DIEGO RIVERANÉSTOR DIEGO RIVERA
NÉSTOR DIEGO RIVERA
JEJoselyn Elizabeth Morales Espinoza
Joselyn Elizabeth Morales Espinoza
GFGabriel Moisés Rodriguez Fernandez
Gabriel Moisés Rodriguez Fernandez
GNGina Pamela Novillo
Gina Pamela Novillo

28 September 2021
Verified
Book Chapter
Closed access
PDF file
NÉSTOR DIEGO RIVERANÉSTOR DIEGO RIVERA
NÉSTOR DIEGO RIVERA
PMPaúl Andrés Molina
Paúl Andrés Molina
ABAndrea Karina Bermeo
Andrea Karina Bermeo
OBOscar Enmanuel Bermeo
Oscar Enmanuel Bermeo
JFJosé Luis Figueroa
José Luis Figueroa