Enmar Khalis

Dr. Enmar Khalis


Research Focus & Metrics

Academic Career Length

2Years (2025-Present)

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

Representative Publications

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20 June 2025 in AI
Verified
Journal Article
Open access
PDF file
AAAli Al-Humairi
Ali Al-Humairi
EKEnmar Khalis
Enmar Khalis
ZAZuhair A.Hamed Al-Hemyari
Zuhair A.Hamed Al-Hemyari
PJPeter Jung
Peter Jung
The performance of photovoltaic systems is highly dependent on environmental conditions, with soiling due to dust accumulation often being referred to as a predominant energy degradation factor, especially in dry and semi-arid environments. This paper introduces an AI-based robotic cleaning system that can independently forecast and schedule cleaning sessions from real-time sensor and environmental data. Methods: The system integrates sources of data like embedded sensors, weather stations, and DustIQ data to create an integrated dataset for predictive modeling. Machine learning models were employed to forecast soiling loss based on significant atmospheric parameters such as relative humidity, air pressure, ambient temperature, and wind speed. Dimensionality reduction through the principal component analysis and correlation-based feature selection enhanced the model performance as well as the interpretability. A comparative study of four conventional machine learning models, including logistic regression, k-nearest neighbors, decision tree, and support vector machine, was conducted to determine the most appropriate approach to classifying cleaning needs. Results: Performance, based on accuracy, precision, recall, and F1-score, demonstrated that logistic regression and SVM provided optimal classification performance with accuracy levels over 92%, and F1-scores over 0.90, demonstrating outstanding balance between recall and precision. The KNN and decision tree models, while slightly poorer in terms of accuracy (around 85–88%), had computational efficiency benefits, making them suitable for utilization in resource-constrained applications. Conclusions: The proposed system employs a dry-cleaning mechanism that requires no water, making it highly suitable for arid regions. It reduces unnecessary cleaning operations by approximately 30%, leading to decreased mechanical wear and lower maintenance costs. Additionally, by minimizing delays in necessary cleaning, the system can improve annual energy yield by 3–5% under high-soiling conditions. Overall, the intelligent cleaning schedule minimizes manual intervention, enhances sustainability, reduces operating costs, and improves system performance in challenging environments.

15 April 2025 in Processes
Verified
Journal Article
Open access
PDF file
AAAli Al-Humairi
Ali Al-Humairi
EKEnmar Khalis
Enmar Khalis
ZAZuhair A.Hamed Al-Hemyari
Zuhair A.Hamed Al-Hemyari
PJPeter Jung
Peter Jung
This study investigates the impact of data augmentation on predictive maintenance machine learning models for robot solar panel cleaning. Data augmentation techniques like synthetic data generation, time-series transformation (shifting, interpolation, and resampling), and extreme condition simulation were used to enhance data diversity and model generalization. Machine learning algorithms, including logistic regression, support vector machines, deep learning, and ensemble learning, were compared to identify their sensitivity to these techniques. Our experimental findings show that ensemble models (stacking and boosting) show the maximum improvement in predictive accuracy with the added benefit of higher diversity and strength in features. Deep learning models show moderate gains primarily in feature extraction, and simple models such as logistic regression show little impact, indicating the model-dependent effectiveness of data augmentation. Despite better generalization, ensemble methods are at the expense of increased computational cost, indicating a trade-off between accuracy and efficiency. The study employs widely used machine learning frameworks and libraries for data preprocessing, augmentation, model training, and evaluation, ensuring robust and scalable implementation.

19 March 2026 in Applied Sciences
Verified
Journal Article
Open access
PDF file
AAAli Al-Humairi
Ali Al-Humairi
EKEnmar Khalis
Enmar Khalis
ZAZuhair A.Hamed Al-Hemyari
Zuhair A.Hamed Al-Hemyari
PJPeter Jung
Peter Jung
This study develops and validates a two-stage comparative framework for predicting Photovoltaic (PV) cleaning schedules by integrating high-resolution operational data with regression-based simulated datasets generated from statistical models trained on real measurements. The work directly addresses the growing need to assess whether model-based regression-based simulated data can reliably substitute real measurements in predictive PV maintenance. These models are employed to generate clean-condition power baselines and to estimate daily energy losses attributable to soiling under two distinct paradigms: (i) using real historical PV performance and environmental measurements, and (ii) using regression-derived, regression-based simulated data representing idealized clean operating conditions. Model performance is rigorously quantified using correlation coefficients (R), coefficients of determination (R2), mean absolute deviations, and binary classification metrics including accuracy, precision, recall, and F1-score. The comprehensive results demonstrate that regression-based simulated datasets exhibit high fidelity with real measurements across key electrical variables. This is evident for datasets generated using PLSR, Ridge Regression, and Robust Regression. Strong correlations are observed for DC power (R2 = 0.9545) and DC current (R2 = 0.9520), with mean deviations consistently below 2.2%. When a threshold-based binary decision rule (“clean” versus “do not clean”) is applied, cleaning decisions derived from simulated and real datasets show near-perfect concordance, achieving a mean F1-score of 0.9792. These results indicate that for a fixed performance-loss threshold, models using regression-based simulated data reproduce real-data-based cleaning triggers with an accuracy exceeding 97%. Furthermore, the findings confirm that regression-based simulation frameworks constitute a reliable and scalable foundation for data-driven PV maintenance optimization. By enabling efficient cleaning scheduling, these frameworks can significantly reduce operational expenditure and maximize energy yield, particularly in regions where continuous, high-quality PV monitoring data are limited or difficult to obtain.