Research
Research
I am a multidisciplinary experimental and computational researcher who combines acoustic/thermoelastic wave physics, material science, and mechanical engineering ideas with sophisticated simulation, experimentation, automation, and Artificial Intelligence to address complex challenges in advanced manufacturing. My research journey started with the experimental investigation of the frictional behavior of polymeric materials in relative motion across varied surface roughness. In graduate school, I focused on Real-Time Release (RTR) Testing of Critical Quality Attributes (CQAs) in Continuous Manufacturing (CM) using advanced automation, AI, and ultrasonic non-destructive techniques. Another area of my expertise is the removal of nano/micro particles from complex geometries using Laser-Induced Plasma (LIP) generated shockwave techniques. Additionally, I collaborate with the Electrical and Computer Engineering department to apply Machine Learning in biometric research.
The physical and mechanical properties of composite materials, such as strength and durability, are highly dependent on their microstructure and micro-viscoelastic properties. Characterizing these aspects is essential, as the microstructure dictates load distribution and damage resistance, while the micro-viscoelastic properties govern time-dependent behaviors like creep and stress relaxation. This characterization is crucial for optimizing material performance in industries like pharmaceutical and aerospace. In this study, the microstructural and micro-viscoelastic properties of pharmaceutical tablets (as composite materials) are correlated with their performance and quality. A systematic, quantitative correlation is established between the microstructural properties of oral solid dosages (OSDs), such as porosity and particle size distribution, and performance characteristics like dissolution rate and hardness. This is achieved through ultrasonic analysis, providing deeper insights into the formulation-process-performance relationships, ultimately improving product development and quality control.
The U.S. pharmaceutical supply chain is vulnerable, and transitioning from batch to continuous manufacturing (CM), supported by the FDA, aims to enhance efficiency and security. My research focuses on addressing gaps in Real-Time Release (RTR) testing in CM to strengthen supply chain resilience. In this study, we are developing a Level I prototype, integrating a blockchain-supported cyber-backbone, ML modeling, and real-time sensor data of the Process Parameters (PPs) and Material Attributes (MAs) from the CM line. This autonomous experimental rig construct with the capacity to characterize physical mechanical, and microstructural properties of 200 pharmaceutical tablets per hour without human intervention ultrasonic non-destructive manner. Collaborative robot (UR3e), Industrial Gripper (EGK MB), BOA Spot Vision System, bowl feeder, line feeder, are integrated to ensure the automation.
Additive Manufacturing (AM) processes are highly unstable, leading to variability in part quality even with consistent parameters, as highlighted in the 2023 AMSC Roadmap. Due to this uncertainty, timely anomaly detection and defect prediction are critical. My research aims to address this gap by focusing on real-time quality assurance and early defect detection in 3D-printed parts in an ultrasonic non-destructive manner. I developed in-situ monitoring systems using ultrasonic and laser-induced techniques to assess build integrity. Key contributions include introducing Phononic Crystal Artifacts (PCAs) for simulating build complexities and optimizing material performance through ultrasonic evaluation. I am currently working on integrating state-of-the-art machine learning algorithms (such as principal component analysis, decision trees, and deep neural networks) with ultrasonic non-destructive evaluation technologies and advanced data analytics to develop a robust autonomous testing system. This system, embedded in 3D printers, is designed to predict quality attributes and enable early defect detection in additive manufacturing and 3D printing processes.
The AMSC 2023 Roadmap highlights a significant research gap, referred to as Gap DE14: Designing to be Cleaned, which notes the absence of design guidelines for ensuring device cleanability after production. In my work on nanoparticle removal from 3D printed parts, I developed a Dry Laser Cleaning (DLC) method that uses laser-induced thermo-elastic waves for non-contact removal of particles, enhancing cleaning efficacy while preventing re-deposition risks. Additionally, I introduced a laser-induced plasma (LIP) shockwave technique, which generates shockwaves to remove particles from intricate geometries in additive manufactured components. Both methods are non-destructive and significantly improve cleaning efficiency, addressing post-production challenges and enhancing the reliability of 3D printed parts, especially for sensitive applications like aerospace and biomedical fields.
Inverse mathematical problems are challenging due to their ill-posed nature, where solutions may be non-unique, highly sensitive to data errors, or nonexistent. They are often nonlinear, computationally expensive, and require regularization techniques to manage instability. In my work, I developed a novel Machine Learning-based (Multi-Output Regression Neural Network) technique for the first time to solve this inverse mathematical problem for extracting micro-viscoelastic and micro-structural properties of compressed pharmaceutical oral solid dosage (OSD) forms directly from ultrasonic waveforms. Synthetic waveforms with a given set of micro-properties of virtual tablets are computationally generated to train, validate, and test the developed ML models for their effectiveness in the inverse problem of recovering specified micro-scale properties.
Ear segmentation is critical in ear-based biometric systems as it ensures accurate feature extraction for reliable human recognition, especially in non-cooperative or contactless settings. I have applied the Novel deep-learning-based MASK-RCNN technique for ear recognition and segmentation in an autonomous manner by providing precise detection and instance segmentation, which is essential for improving the performance of ear recognition systems, particularly in complex or real-world scenarios. Its effectiveness in isolating the ear from challenging backgrounds enhances the accuracy of biometric identification. Additionally, I have demonstrated the effectiveness of the Deep Learning-based segmentation technique for post-mortem human iris segmentation.
[1] “Precision micro-particle removal from through-holes via laser-induced plasma shockwaves in additive manufacturing,” T. Sultan, E. H. Rozin, X. Xu, A. Chakrobarty, and C. Cetinkaya, Journal of Manufacturing Processes, vol. 131, pp. 412–426, Dec. 2024, doi: 10.1016/j.jmapro.2024.09.046.
[2] “Analyzing the impact of selective laser melting print speed on internal resonance structures of metallic phononic crystal artifacts for process monitoring,” E. H. Rozin, T. Sultan, H. Taheri, and C. Cetinkaya, Int J Adv Manuf Technol, Sep. 2024, doi: 10.1007/s00170-024-14474-y.
[3] “Non-contact targeted removal of remnant powder particles from additive manufacturing builds with nano-second laser pulsing,” E. H. Rozin, T. Sultan, and C. Cetinkaya, Journal of Manufacturing Processes, vol. 124, pp. 163–173, Aug. 2024, doi: 10.1016/j.jmapro.2024.06.014.
[4] “Ultrasonic Evaluation of Laser Scanning Speed Effect on the Spectral Properties of Three-Dimensional-Printed Metal Phononic Crystal Artifacts,” E. H. Rozin, T. Sultan, H. Taheri, and C. Cetinkaya, 3D Printing and Additive Manufacturing, vol. 11, no. 3, pp. e1087–e1099, Jun. 2024, doi: 10.1089/3dp.2022.0259.
[5] “Machine learning modeling for ultrasonic quality attribute assessment of pharmaceutical tablets for continuous manufacturing and real-time release testing,” T. Sultan, E. H. Rozin, S. Paul, Y.-C. Tseng, V. S. Dave, and C. Cetinkaya, International Journal of Pharmaceutics, vol. 655, p. 124049, Apr. 2024, doi: 10.1016/j.ijpharm.2024.124049.
[6] “Detecting Selective Laser Melting Beam Power from Ultrasonic Temporal and Spectral Responses of Phononic Crystal Artifacts Toward In-Situ Real-Time Quality Monitoring,” E. H. Rozin, T. Sultan, H. Taheri, and C. Cetinkaya, 3D Printing and Additive Manufacturing, Dec. 2023, doi: 10.1089/3dp.2023.0063.
[7] “Machine learning framework for extracting micro-viscoelastic and micro-structural properties of compressed oral solid dosage forms,” T. Sultan, E. Hasan Rozin, S. Paul, Y.-C. Tseng, and C. Cetinkaya, International Journal of Pharmaceutics, vol. 646, p. 123477, Nov. 2023, doi: 10.1016/j.ijpharm.2023.123477.
[8] “Quantifying the anisotropic elasticity of 3D printed phononic artifacts with ultrasound for process monitoring,” M. S. Sutopa, T. Sultan, E. H. Rozin, and C. Cetinkaya, Journal of Manufacturing Processes, vol. 101, pp. 1188–1204, Sep. 2023, doi: 10.1016/j.jmapro.2023.07.001.
[9] “Monitoring for the effects of extruder nozzle temperature on the micro-mechanical properties of 3D printed phononic artifacts,” M. S. Sutopa, T. Sultan, E. H. Rozin, X. Xu, J. Gardan, and C. Cetinkaya, Journal of Manufacturing Processes, vol. 98, pp. 337–350, Jul. 2023, doi: 10.1016/j.jmapro.2023.05.035.
[10] “Non-destructive detection of disintegrant levels in compressed oral solid dosage forms,” T. Sultan, E. Hasan Rozin, V. S. Dave, and C. Cetinkaya, International Journal of Pharmaceutics, vol. 642, p. 123171, Jul. 2023, doi: 10.1016/j.ijpharm.2023.123171.
[11] “Early detection and assessment of invisible cracks in compressed oral solid dosage forms,” T. Sultan, V. S. Dave, and C. Cetinkaya, International Journal of Pharmaceutics, vol. 635, p. 122786, Mar. 2023, doi: 10.1016/j.ijpharm.2023.122786.
[12] “Micro-viscoelastic Characterization of Compressed Oral Solid Dosage Forms with Ultrasonic Wave Dispersion Analysis,” T. Sultan, S. Paul, E. H. Rozin, Y.-C. Tseng, M. C. F. Bazzocchi, and C. Cetinkaya, AAPS PharmSciTech, vol. 24, no. 1, p. 22, Dec. 2022, doi: 10.1208/s12249-022-02483-7.
[13] “Effect of shape on the physical properties of pharmaceutical tablets,” T. Sultan et al., International Journal of Pharmaceutics, vol. 624, p. 121993, Aug. 2022, doi: 10.1016/j.ijpharm.2022.121993.
[14] “Ultrasonic characterization of complete anisotropic elasticity coefficients of compressed oral solid dosage forms,” T. Sultan, S. Paul, E. Hasan Rozin, C. Canino, Y.-C. Tseng, and C. Cetinkaya, International Journal of Pharmaceutics, vol. 623, p. 121922, Jul. 2022, doi: 10.1016/j.ijpharm.2022.121922.
[15] “Post-Mortem Human Iris Segmentation Analysis with Deep Learning,” A. Hossain, T. Sultan, and S. Schuckers, Aug. 06, 2024, arXiv: arXiv:2408.03448. doi: 10.48550/arXiv.2408.03448.
[16] “Deep Learning Approach for Ear Recognition and Longitudinal Evaluation in Children,” A. Hossain, T. Sultan, and S. Schuckers, Aug. 02, 2024, arXiv: arXiv:2408.01588. Accessed: Sep. 21, 2024. [Online]. Available: http://arxiv.org/abs/2408.01588