It has been widely recognized that engineering design should account for the stochastic nature of random parameters in engineered systems. In this research area, the techniques of reliability analysis and design optimization are integrated to develop reliability-based design methodologies that offer probabilistic approaches to engineering design. Reliability-based design attempts to find the optimum design that minimizes the cost and satisfies a target reliability, while accounting for various sources of uncertainty. In the design space, reliability-based design pushes the deterministic optimum design back to the reliable region to create a safety margin that accommodates the uncertainty in parameters and design variables. My research has been focused on developing computationally efficient methods for uncertainty propagation, and component and system reliability analyses for complex engineered systems that involve expensive simulations and/or large dimensions. My research aims to develop theoretically sound, and self-consistent methods to support engineering design under uncertainty.

I have investigated the stochastic spectral and collocation methods to reduce the number of function evaluations required by reliability analysis. The investigation has led to the development of several computationally efficient methods that could drastically reduce the cost of reliability analysis and significantly broaden the application of reliability-based design in modern complex systems. These methods can be used by design engineers in private industries, government, and academic fields to obtain the optimal design for various engineered systems such as vehicles, space shuttles, aircraft, and ships.

Software code: The stochastic response surface method (SRSM) toolkit was developed that integrates univariate dimension reduction (UDR) with cubic spline interpolation to build a stochastic response surface. The toolkit provides an efficient uncertainty propagation strategy that promotes the wide-scale application of engineering design under uncertainty.

Recent Publications

1. Nemani V.P., Liu J., Ahmed N., Cartwright A., Kremer G.E., and Hu C., “Reliability-Informed Economic and Energy Evaluation for Bi-Level Design for Remanufacturing: A Case Study of Transmission and Hydraulic Manifold,” Journal of Mechanical Design, v144, n8, 08214 (17pp), 2022.
2. Li M., Shen S., Barzegar V., Sadoughi M., Hu C., and Laflamme S., “Kriging-Based Reliability Analysis Considering Predictive Uncertainty Reduction,” Structural and Multidisciplinary Optimization, v63, p2721–2737, 2021.
3. Li M., Nemani V.P., Liu J., Lee M.A., Ahmed N., Kremer G.E., and Hu C., “Reliability-Informed Life Cycle Warranty Cost and Life Cycle Analysis of Newly Manufactured and Remanufactured Units,” Journal of Mechanical Design, v143, n11, 112001 (14pp), 2021.
4. Sadoughi M., Hu C., Moghadassian B., Sharma A., Beck J., and Mathiesen D., “Sequential Online Dispatch in Design of Experiments for Single- and Multi-Response Surrogate Modeling,” IEEE Transactions on Automation Science and Engineering, v17, n4, p1674–1688, 2020.
5. Li M., Sadoughi M., Hu Z., and Hu C., “A Hybrid Gaussian Process Model for System Reliability Analysis,”, Reliability Engineering and System Safety, v197, 106816 (15pp), 2020.
6. Li M., Sadoughi M., Hu C., Hu Z., EshghiT., and Lee S., “High-Dimensional Reliability-Based Design Optimization Involving Highly Nonlinear Constraints and Computationally Expensive Simulations,” Journal of Mechanical Design, v141, n5, 051402 (14pp), 2019.
7. Hu Z., Hu C., ZissimosM., and Sankaran M., “Model Discrepancy Quantification in Simulation-based Design of Dynamical Systems,” Journal of Mechanical Design, v141, n1, 011401 (13pp), 2018.
8. Sadoughi M., Li M., and Hu C., “Multivariate System Reliability Analysis Considering Highly Nonlinear and Dependent Safety Events,” Reliability Engineering and System Safety, v180, p189–200, 2018.
9. Sadoughi M., Li M., Hu C., MacKenzie C., EshghiT., and Lee S., “A High-Dimensional Reliability Analysis Method for Simulation-Based Design Under Uncertainty,” Journal of Mechanical Design, v140, n7, 071401 (12pp), 2018.
10. Sadoughi M., Hu C., MacKenzie C., EshghiT., and Lee S., “Sequential Exploration-Exploitation with Dynamic Trade-off for Efficient Reliability Analysis of Complex Engineered Systems,” Structural and Multidisciplinary Optimization, v57, n1, p235–250, 2018.
11. Eshghi A.T., Lee S., Sadoughi M., Hu C., Kim C., and Seo J.H., “Design Optimization under Uncertainty and Speed Variability for a Piezoelectric Energy Harvester Powering a Tire Pressure Monitoring Sensor,” Smart Materials and Structures, v26, n10, 105037, p1–18, 2017.