Alam Gabriel Rojas-López

Dr. Alam Gabriel Rojas-López

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Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

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

Representative Publications

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29 December 2023 in Expert Systems with Applications
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ARAlam Gabriel Rojas-López
Alam Gabriel Rojas-López
Miguel Gabriel CervantesMiguel Gabriel Cervantes
Miguel Gabriel Cervantes
ARAlejandro Rodríguez-Molina
Alejandro Rodríguez-Molina

14 February 2025 in Biomimetics
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ARAlam Gabriel Rojas-López
Alam Gabriel Rojas-López
Miguel Gabriel CervantesMiguel Gabriel Cervantes
Miguel Gabriel Cervantes
Alejandro Rodríguez-MolinaAlejandro Rodríguez-Molina
Alejandro Rodríguez-Molina
JPJesús Aldo Paredes-Ballesteros
Jesús Aldo Paredes-Ballesteros
The growing reliance on mobile robots has resulted in applications where users have limited or no control over operating conditions. These applications require advanced controllers to ensure the system’s performance by dynamically changing its parameters. Nowadays, online bioinspired controller tuning approaches are among the most successful and innovative tools for dealing with uncertainties and disturbances. Nevertheless, these bioinspired approaches present a main limitation in real-world applications due to the extensive computational resources required in their exhaustive search when evaluating the controller tuning of complex dynamics. This paper develops an online bioinspired controller tuning approach leveraging a surrogate modeling strategy for an omnidirectional mobile robot controller. The polynomial response surface method is incorporated as an identification stage to model the system and predict its behavior in the tuning stage of the indirect adaptive approach. The comparative analysis concerns state-of-the-art controller tuning approaches, such as online, offline robust, and offline non-robust approaches, based on bioinspired optimization. The results show that the proposal reduces its computational load by up to 62.85% while maintaining the controller performance regarding the online approach under adverse uncertainties and disturbances. The proposal also increases the controller performance by up to 93% compared to offline tuning approaches. Then, the proposal retains its competitiveness on mobile robot systems under adverse conditions, while other controller tuning approaches drop it. Furthermore, a posterior comparison against another surrogate tuning approach based on Gaussian process regression corroborates the proposal as the best online controller tuning approach by reducing the competitor’s computational load by up to 91.37% while increasing its performance by 63%. Hence, the proposed controller tuning approach decreases the execution time to be applied in the evolution of the control system without deteriorating the closed-loop performance. To the best of the authors’ knowledge, this is the first time that such a controller tuning strategy has been tested on an omnidirectional mobile robot.

27 May 2025 in Mathematics
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JPJesús Aldo Paredes-Ballesteros
Jesús Aldo Paredes-Ballesteros
Miguel Gabriel CervantesMiguel Gabriel Cervantes
Miguel Gabriel Cervantes
SBSaul Enrique Benitez-Garcia
Saul Enrique Benitez-Garcia
Alejandro Rodríguez-MolinaAlejandro Rodríguez-Molina
Alejandro Rodríguez-Molina
ARAlam Gabriel Rojas-López
Alam Gabriel Rojas-López
VSVíctor Silva-García
Víctor Silva-García
Robotic systems operating in complex environments require optimized tuned interaction controllers to ensure accurate task execution while maintaining smooth and safe behavior. This paper presents a scalarized multi-objective tuning approach based on Differential Evolution (DE) to optimize robot–environment interaction control. The method balances trajectory tracking accuracy and control smoothness using repulsive forces derived from potential fields modeled as virtual springs. The approach is validated on a (3,0) omnidirectional mobile robot navigating predefined trajectories with obstacles. A comparative study of five DE variants shows that DE/best/1/bin and DE/best/1/exp offer the best performance. Simulation and experimental results, including validation with an actual force sensor, confirm the method’s effectiveness and applicability in scenarios with limited sensing capabilities or model uncertainty.

2 July 2024 in Healthcare
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ARAlam Gabriel Rojas-López
Alam Gabriel Rojas-López
Alejandro Rodríguez-MolinaAlejandro Rodríguez-Molina
Alejandro Rodríguez-Molina
AUAbril Valeria Uriarte-Arcia
Abril Valeria Uriarte-Arcia
Miguel Gabriel CervantesMiguel Gabriel Cervantes
Miguel Gabriel Cervantes
One expanding area of bioinformatics is medical diagnosis through the categorization of biomedical characteristics. Automatic medical strategies to boost the diagnostic through machine learning (ML) methods are challenging. They require a formal examination of their performance to identify the best conditions that enhance the ML method. This work proposes variants of the Voting and Stacking (VC and SC) ensemble strategies based on diverse auto-tuning supervised machine learning techniques to increase the efficacy of traditional baseline classifiers for the automatic diagnosis of vertebral column orthopedic illnesses. The ensemble strategies are created by first combining a complete set of auto-tuned baseline classifiers based on different processes, such as geometric, probabilistic, logic, and optimization. Next, the three most promising classifiers are selected among k-Nearest Neighbors (kNN), Naïve Bayes (NB), Logistic Regression (LR), Linear Discriminant Analysis (LDA), Quadratic Discriminant Analysis (QDA), Support Vector Machine (SVM), Artificial Neural Networks (ANN), and Decision Tree (DT). The grid-search K-Fold cross-validation strategy is applied to auto-tune the baseline classifier hyperparameters. The performances of the proposed ensemble strategies are independently compared with the auto-tuned baseline classifiers. A concise analysis evaluates accuracy, precision, recall, F1-score, and ROC-ACU metrics. The analysis also examines the misclassified disease elements to find the most and least reliable classifiers for this specific medical problem. The results show that the VC ensemble strategy provides an improvement comparable to that of the best baseline classifier (the kNN). Meanwhile, when all baseline classifiers are included in the SC ensemble, this strategy surpasses 95% in all the evaluated metrics, standing out as the most suitable option for classifying vertebral column diseases.


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Daniel Molina-PérezDaniel Molina-Pérez
Daniel Molina-Pérez
ARAlam Gabriel Rojas-López
Alam Gabriel Rojas-López
This article addresses the complex challenge of simultaneously enhancing contrast and detail in an image, where improving one property often compromises the other. This trade-off is tackled using a multi-objective optimization approach. Specifically, the proposal’s model integrates the sigmoid transformation function and unsharp masking highboost filtering with the NSGA-II algorithm. Additionally, a posterior preference articulation is introduced to select three key solutions from the Pareto front: the maximum contrast solution, the maximum detail solution, and the knee point solution. The proposed technique is evaluated on a range of image types, including medical and natural scenes. The final solutions demonstrated significant superiority in terms of contrast and detail compared to the original images. The three selected solutions, although all are optimal, captured distinct characteristics within the images, offering different solutions according to field preferences. This highlights the method’s effectiveness across different types and enhancement requirements and emphasizes the importance of the proposed preferences in different contexts.