1. Full name: Nguyen Nhu Hieu                                       2. Sex: Male

3. Date of birth: December 14, 1984                               4. Place of birth: Bac Ninh province

5. Admission decision number: No. 3485/QĐ-KHTN-CTSV, dated on 14 September 2012 by Rector of VNU University of Science.

6. Changes in academic process: Decision No. 741/QĐ-ĐHKHTN on 31 March 2016 by Rector of VNU University of Science]; and decision No. 1034/QĐ-ĐHKHTN on 25 April 2017 by Rector of VNU University of Science].

7. Official thesis title: "A dual criterion of equivalent linearization method for nonlinear multi-degree-of-freedom systems subjected to random excitations"

8. Major: Mechanics      of Solids                                 9. Code: 62440107

10. Supervisors: Prof. Dr. Nguyen Dong Anh; and Assoc. Prof. Dr. Ninh Quang Hai        

11. Summary of the new findings of the thesis

- Extending the dual criterion of equivalent linearization method to multi-degree-of-freedom systems subjected to random excitations

- Formulating a system of closed algebraic equations and corresponding solution procedure for equivalent linearization coefficients

- Applying the dual criterion of equivalent linearization method to investigate nonlinear responses of beam vibrations

- The numerical calculations show that the proposed dual criterion gives a better prediction on system responses than that of  conventional linearization method when the nonlinearity is increasing.

12. Paratical applicability, if any:

The investigated results of the thesis can be applied to the fields of vibration control for building structures; vibration reduction solutions for machines, engineering equipment, vehicle systems; nonlinear dynamic systems with thermal interaction; behaviors of Brownian motions; applications in pre-design stages of various engineering systems. 

13. Further research directions, if any

- Extending the dual criterion of equivalent linearization method to wider classes of stochastic dynamic systems, for example, continuous and discontinuous systems, parametric excitation systems, and systems with complex external loadings;

- Investigating the problem of selecting relevant detuning parameters for dual criterion in both singe and multi-degree-of-freedom systems in order to improve the accuracy and effectiveness of equivalent linearization method.

14. Thesis-related publications:

[1] Anh N.D., Zakovorotny V.L., Hieu N.N., Diep D.V. (2012), "A dual criterion of stochastic linearization method for multi-degree-of-freedom systems subjected to random excitation", Acta Mechanica, 223, pp. 2667-2684. (SCI journal paper)

[2] Anh N.D., Elishakoff I., Hieu N.N. (2014), "Extension of the regulated stochastic linearization to beam vibrations", Probabilistic Engneering Mechanics, 36, pp. 2-10. (SCI journal paper)

[3] Hieu N.N., Anh N.D., Hai N.Q. (2016), "Vibration analysis of beams subjected to random excitation by the dual criterion of equivalent linearization", Vietnam Journal of Mechanics, VAST, 38, pp. 49-62. (national journal paper)

[4] Anh N.D., Hieu N.N. (2012), "The probability density functions of responses of a two-degree-of-freedom system under random excitation using the dual criterion of stochastic linearization method", Proceedings of the 9th National Conference on Mechanics, Hanoi, Dec 8-9, 2012, pp. 1-11.

[5] Anh N.D., Hai N.Q., Hieu N.N. (2012), "Responses of a two-degree-of-freedom system under random excitation by the dual criterion of stochastic linearization method", The 2nd International Conference on Engineering Mechanics and Automation (ICEMA2), Hanoi, August 16-17, pp. 71-78.

[6] Hieu N.N., Anh N.D., Hai N.Q. (2015), "Phân tích dao động ngẫu nhiên phi tuyến của dầm mang khối lượng tập trung sử dụng phương pháp tuyến tính hóa tương đương theo tiêu chuẩn đối ngẫu", Hội nghị Khoa học toàn quốc Cơ học Vật rắn biến dạng lần thứ XII, Đại học Duy Tân, Tp. Đà Nẵng, 7/8/2015, tr. 543-550.