sknagar.eee's picture
Dr. S. K. Nagar
Professor
Department of Electrical Engineering Indian Institute of Technology
sknagar.eee@iitbhu.ac.in
9839888628
Area of Interest: 
Control Systems, Large Scale Systems, AI Applications

B. Tech. (1976) - BHU
M. Tech. (1978) - BHU
Ph.D (1991) - University of Roorkee (UOR)

1980 to 1993 - Lecturer in Electrical Engineering (BHU)
1993 to 2001 - Reader in Electrical Engineering (BHU)
2001 onwards - Professor of Electrical Engineering (BHU)

Book published - Modern Control Systems with Advanced Topics (New Age Publishers, India)
No. of Papers in National and International Journals - 40
No. of Papers in National and International Conferences - 35

Life Member of Systems Society of India
Fellow of Institution of Engineers (India)

Invited Talks:

        1. Small Workshop on Interval Methods, Session Chairman, ENSTA Bretagne, Brest, France, June 5-7, 2013
        2. IEEE INDICON 2013, Session chairman, IIT Bombay, Dec 12-14, 2013.
        3. Presented a paper on “ Direct truncation method for order reduction of discrete interval systems”, IEEE INDICON 2013, 13-15 Dec, 2013, IIT Bombay, India.
        4. CERA 2013, Plenary talk on “Supervisory control of discrete event systems”, IIT Roorkee, Oct 2013.
        5. CISCON 2010, Plenary talk on “Modelling and supervisory control of discrete event systems”, Manipal Institute of Technology, August 2010.
        6. Presented a paper on “ Model order reduction of S.I.S.O and M.I.M.O systems based on genetic Algorithm”, International Conference on Automation, Robotics and Control Systems (ARCS-10), July 12-14, 2010 in Orlando, FL, USA.

Papers published in Regular Journals:

  1. M. Juneja, S. K. Nagar, S. R. Mohanty, “ABC based reduced order modelling of microgrid in grid-tied mode”, Control Engineering Practice, vol. 84, pp. 337-348, 2019.
  2. A. K. Choudhary and S. K. Nagar, “Order Reduction in z-domain Interval System using an Arithmetic Operator”, Circuits, Systems and Signal Processing, Springer, https://doi.org/10.1007/s00034-018-0912-7, 2019.
  3. V. K. Jaiswal, A. Singh, S. Yadav and S. K. Nagar, “Controlling of Non-minimum Phase System Using Harmony Search Algorithm”, Data and Communication Networks, pp. 185-194. Springer, Singapore, 2019.
  4. M. Mandal, M. Chaudhary, S. K. Vipparthi, A. B. Gonde, S. K. Nagar, “ANTIC: antithetic isomeric cluster patterns for medical image retrieval and change detection”, IET Computer Vision, vol. 13, pp. 31-43, 2019.
  5. A. K. Choudhary and S. K. Nagar, “Model Order Reduction of Discrete-time Interval Systems by Differential Calculus”, Automatic Control and Computer Sciences, Springer, vol. 52, no. 5, pp. 402–411, https://doi.org/10.3103/S0146411618050073, 2018.
  6. M. Juneja and S. K. Nagar, “An improvement in LQR controller design for TLIP system via model order reduction”, International Journal of Engineering Research and Technology, 11 (12), pp. 1891-1900, 2018.
  7. A. K. Choudhary and S. K. Nagar, “Model order reduction of discrete-time interval system based on Mikhailov stability criterion”, Journal of Dynamics and Control, https://doi.org/10.1007/s40435-018-0404-4, 2018.
  8. A. K. Choudhary and S. K. Nagar, “Order Reduction Techniques via Routh Approximation, A Critical Survey”, IETE Journal of Research, https://doi.org/10.1080/03772063.2017.1419836, 2018.
  9. S. Yadav, S. K. Verma, and S. K. Nagar, “Performance enhancement of magnetic levitation system using teaching learning based optimization”, Alexandria Engineering Journal 57, no. 4, pp. 2427-2433, 2018.
  10. A. K. Choudhary and S. K. Nagar, “Novel arrangement of Routh array for order reduction of z -domain uncertain system”, Systems Science & Control Engineering, vol.5, no.1, pp. 232-242, 2017.
  11. S. K. Verma, S. Yadav, and S. K. Nagar, “Optimization of Fractional Order PID Controller Using Grey Wolf Optimizer”, Journal of Control, Automation and Electrical Systems, vol. 28, no. 3, pp. 314-322, 2017.
  12. O. P. Bharti, R. K. Saket, S. K. Nagar, “Controller design for doubly fed induction generator using particle swarm optimization technique”, Renewable Energy, vol. 114, pp. 1394-1406, 2017.
  13. A. K. Choudhary, S. K. Nagar, “Novel arrangement of Routh array for order reduction of z-domain uncertain system”, Systems Science and Control Engineering, vol. 5, pp. 232-242, 2017.
  14. A. K. Choudhary and S. K. Nagar, “Revisiting Approximation Techniques to Reduce Order of Interval System”, IFAC PaperOnline, vol. 49, no. 2, pp. 241-246, 2016.
  15. S. K. Vipparthi, S. K. Nagar, “Local extreme complete trio pattern for multimedia image retrieval system”, International Journal of Automation and Computing, vol. 13, pp. 457-467, 2016.
  16. A. K. Choudhary and S. K. Nagar, “Application of Various Order Reduction Methodologies over Power System Components”, IFAC PaperOnline, vol. 48, no. 30, pp. 185-190, 2015.
  17. S. K. Vipparthi, S. Murala, S. K. Nagar, “Local Gabor maximum edge position octal patterns for image retrieval”, Neurocomputing, vol. 167, pp. 336-345, 2015.
  18. S. K. Vipparthi, S. Murala, S. K. Nagar, “Dual directional multi-motif XOR patterns: A new feature descriptor for image indexing and retrieval”, OPTIK, vol. 126, pp. 1467-1473, 2015.
  19. S. K. Vipparthi, S. K. Nagar, “Integration of Color and Local Derivative Pattern Features for Content-Based Image Indexing and Retrieval”, Journal of The Institution of Engineers (India): Series B, vol. 96, pp. 251-263, 2015.
  20. S. K. Vipparthi, S. K. Nagar, “Directional local ternary patterns for multimedia image indexing and retrieval”, International Journal of Signal and Imaging Systems Engineering, vol. 8, pp. 137-145, 2015.
  21. K. M. Goud, S. K. Nagar, “Fractional order PD controller design for non-monotonic phase systems”, Imternational Journal of Automation and Control, vol. 9, pp. 130-142, 2015.
  22. D. Kumar and S. K. Nagar, “Model reduction by extended minimal degree optimal Hankel norm approximation”, Applied Mathematical Modelling, vol. 38, no. 11-12, pp. 2922-2933, 2014.
  23. S. K. Vipparthi, S. K. Nagar, “Expert image retrieval system using directional local motif XoR patterns”, Expert Systems with Applications, vol. 41, pp. 8016-8026, 2014.
  24. S. K. Vipparthi, S. K. Nagar, “Multi-joint histogram based modelling for image indexing and retrieval”, Computers and Electrical Engineering, vol. 40, pp. 163-173, 2014.
  25. D. Kumar, S. K. Nagar, “Model reduction by extended minimal degree optimal Hankel norm approximation”, Applied Mathematical Modelling, vol. 38, pp. 2922-2933, 2014.
  26. S. K. Vipparthi, S. K. Nagar, “Color Directional Local Quinary Patterns for Content Based Indexing and Retrieval”, Human-centric Computing and Information Sciences, vol. 4, pp. 1-3, 2014.
  27. S. K. Vipparthi, S. K. Nagar, “Directional local quinary patterns: A new feature descriptor for image indexing and retrieval”, Advances in Intelligent Systems and Computing, vol. 243, pp. 837-844, 2014.
  28. D. Kumar and S. K. Nagar, “Reducing power system models by Hankel norm approximation technique”, International Journal of Modelling and Simulation, vol. 33, no. 3, pp. 139-143, 2013.
  29. D. Kumar, S. K. Nagar, J. P. Tiwari, “Order reduction of interval systems using alpha and factor division method”, Lecture Notes in Electrical Engineering (LNEE), vol. 188, pp. 249-259, 2013.
  30. D. Kumar, J. P. Tiwari and S. K. Nagar, “Reducing order of large-scale systems by extended balanced singular perturbation approximation”, International Journal of Automation and Control, vol. 6, no. 1, pp. 21-38, 2012.
  31. D. Kumar, J. P. Tiwari and S. K. Nagar, “Controller reduction by balanced approach with guaranteed closed-loop performance”, International Journal of Automation and Control, vol. 6, no. 2, pp. 105-119, 2012.
  32. S. Yadav, J. P. Tiwari and S. K. Nagar, “Digital Control of Magnetic Levitation System using Fuzzy Logic Controller”, International Journal of Computer Applications (0975 – 8887), vol. 41, no.21, March 2012.
  33. D. Kumar, J. P. Tiwari and S. K. Nagar, “Reduction of unstable discrete time systems by Hankel norm approximation”, International Journal of Engineering Science and Technology, vol. 3, no. 4, 2011.
  34. S. Yadav, J. P. Tiwari and S. K. Nagar, “Optimal Control of Inverted Pendulum using Fuzzy Logic, PID & LQR Controller”, International Journal of Advance Science and Technology (2229 5216), vol. 3, no. 4, November 2011.
  35. D. Kumar, J. P. Tiwari and S. K. Nagar, “Reduction of large scale systems by extended balanced truncation approach”, International Journal of Engineering Science and Technology, vol. 3, no. 4, pp. 2746-2752, 2011.
  36. S. Yadav, J. P. Tiwari and S. K. Nagar, “Optimal Control of Inverted Pendulum using Ant Colony System Algorithm”, International Journal of Computer Information Systems (2229 5208), vol. 3, no. 4, November 2011.
  37. A. Singh, S. Yadav , J. P. Tiwari and S. K. Nagar, “Techniques for Digital Redesign of Analog controllers”, International Journal of Computer Information Systems (2229 5208), vol. 3, no. 4, November 2011.
  38. S. K. Nagar, S. K. Singh, “An algorithmic approach for system decomposition and balanced realized model reduction”, Journal of the Franklin Institute – Engineering and Applied Mathematics, vol. 341, pp. 615-630, 2004.
  39. S. K. Nagar, A. Banerjee, A. Sivasubramaniam, “Alternatives to coscheduling a network of workstations”, vol. 59, pp. 302-327, 1999.
  40. A. K. Sahani, S. K. Nagar, “Design of digital controllers for multivariable systems via time-moments matching”, Computers & Electrical Engineering, vol. 24, pp. 335-347, 1998.
  41. A. K. Sahani, S. K. Nagar, “Digital controller design algorithm using time-moments and Markov parameters matching”, Control and Intelligent Systems, vol. 26, pp. 42-49, 1998.
  42.  A. K. Sahani, S. K. Nagar, “Model reduction of discrete-time systems via frequency response matching”, Computers and Electrical Engineering, vol. 23, pp. 195-203, 1997.
  43. A. K. Sahani, S. K. Nagar, “An algorithmic approach for multivariable digital controller design”, Control and Computers, vol. 24, pp. 29-35, 1996.
  44. J. Pal, S. K. Nagar, J. D. Sharma, “Digital Controller-Design for Systems with Transport Lag”, vol. 23, pp. 2385-2392, 1992.
  45. S. K. Nagar, J. Pal, J. D. Sharma, “A Computer-aided method for Digital Controller-Design via Optimization”, Computers & Electrical Engineering, vol. 16, pp. 79-85, 1990.
  46. S. K. Nagar, T. Nagaraja, “A modified parameter identification algorithm in state space”, Computers and Electrical Engineering, vol. 8, pp. 103-107, 1981

Papers published in Conferences:

  1. S. Yadav, A. Mishra and S. K. Nagar, “Tuning of parameters of PID controller using Grey Wolf Optimizer”, International conference on Advances in Electronics: Electrical: Computational Intelligence, 2019.  (accepted & presented)
  2. A. K. Choudhary and S. K. Nagar, “A Novel Technique for Order Reduction of Discrete-Time Interval System”, 4thSICE International Symposium on Control Systems (ISCS), at Setagaya Campus, Tokyo City University, Tokyo, Japan, March 9-11, 2018.
  3. M. Juneja, S. K. Nagar, “Particle swarm optimization and its parameters: A review”, 2nd IEEE International Conference on Control, Computing, Communication and Materials, 2017.
  4. O. P. Bharti, R. K. Saket, S. K. Nagar, “Reliability analysis of DFIG based wind energy conversion system”, ACM International Conference Proceeding Series, part F127852, pp. 313-317, 2017.
  5. S. K. Verma, S. K. Nagar, “Approximation and order reduction of fractional order SISO system”, IEEE Annual India Conference (INDICON), 7839060, 2017.
  6. A. K. Choudhary and S. K. Nagar, “Simplification of Uncertain System to Their Approximate Model”, SIAM Conference on Uncertainty Quantification (UQ16), SwissTech Convention Center, EPFL Campus, Lausanne, Switzerland, April 5-8, 2016.
  7. S. K. Verma, S. Yadav and S. K. Nagar, “Optimized fractional order PID controller for non-minimum phase system with time delay”, In 2016 International Conference on Emerging Trends in Electrical Electronics & Sustainable Energy Systems (ICETEESES), pp. 169-173. IEEE, 2016.
  8. S. Yadav, S. K. Verma, and S. K. Nagar, “Optimized PID controller for magnetic levitation system”, IFAC-PapersOnLine 49, no. 1, pp.778-782, 2016.
  9. S. K. Verma, S. Yadav and S. K. Nagar, “Fractional order PI controller design for non-monotonic phase systems”, IFAC-PapersOnLine 49, no. 1, pp. 236-240, 2016.
  10. S. Yadav, S. K. Verma and S. K. Nagar, “Reduction and controller design for fractional order Spherical tank system using GWO”, In 2016 International Conference on Emerging Trends in Electrical Electronics & Sustainable Energy Systems (ICETEESES), pp. 174-178. IEEE, 2016.
  11. S. K. Verma, S. Yadav, S. K. Nagar, “Controlling of an automatic voltage regulator using optimum integer and fractional order PID controller”, IEEE Workshop on Computational Intelligence: Theories, Applications and Future Directions (WCI), 7495525, 2016.
  12. S. Yadav, S. K. Verma, S. K. Nagar, “Design of and optimized PID controller for non-minimum phase system with delay”, Proceedings of the 39th National Systems Conference (NSC), 7489096, 2016.
  13. O. P. Bharti, R. K. Saket, S. K. Nagar, “Design of PI controller for doubly fed induction generator using static output feedback”, Proceedings of the 39th National Systems Conference (NSC), 7489128, 2016.
  14. A. K. Choudhary, S. K. Nagar, “Revisiting approximation techniques to reduce order of interval system”, IFAC-PapersOnLine, vol. 49, pp. 241-246, 2016.
  15. A. K. Choudhary, S. K. Nagar, “Application of Various Order Reduction Methodologies over Power System Components”, IFAC-PapersOnLine, vol. 48, pp. 185-190, 2015.
  16. S. Yadav, S. K. Verma and S. K. Nagar, “Design of an optimized PID controller for non-minimum phase system with delay”, In 2015 39th National Systems Conference (NSC), pp. 1-4. IEEE, 2015.
  17. S. K. Verma, S. Yadav and S. K. Nagar, “Optimal fractional order PID controller for magnetic levitation system”, In 2015 39th National Systems Conference (NSC), pp. 1-5. IEEE, 2015.
  18. D. Kumar and S. K. Nagar, “Frequency weighted square-root optimal Hankel norm model reduction”, 2015 10th Asian Control Conference (ASCC), pp. 1-4, 2015.
  19. S. K. Verma, S. Yadav and S. K. Nagar, “Controlling of an automatic voltage regulator using optimum integer and fractional order PID controller”, In 2015 IEEE Workshop on Computational Intelligence: Theories, Applications and Future Directions (WCI), pp. 1-5. IEEE, 2015.
  20. A. K. Choudhary and S. K. Nagar,  “Order Reduction of Uncertain System using the Advantages of Two Varied Approximations”, Michael Faraday IET International Summit (MFIIS-2015), Kolkata, India,pp. 49-51, Sept. 12-13, 2015.
  21. D. Kumar, S. K. Nagar, “Order reduction of power system models using square-root balanced approach”, 18th National Power Systems Conference (NPSC), 7103801, 2015.
  22. M. Juneja, S. K. Nagar, “Comparative study of Model Order Reduction using combination of PSO with conventional reduction techniques”, International Conference on Industrial Instrumentation and Control (ICIC), 7150776, pp. 406-411, 2015.
  23. D. Kumar and S. K. Nagar, “Square-root optimal hankel norm approximation technique for order reduction of non-minimal systems”, 2014 International Electrical Engineering Congress (IEECON), pp. 1-4, 2014.
  24. D. Kumar and S. K. Nagar, “Square-root Frequency Weighted balanced model reduction via singular perturbation approximation”, 2014 International Electrical Engineering Congress (IEECON), pp. 1-4, 2014.
  25. D. Kumar and S. K. Nagar, “Order reduction of power system models using square-root balanced approach”, 2014 Eighteenth National Power Systems Conference (NPSC), pp. 1-6, 2014.
  26. A. K. Choudhary and S. K. Nagar, “Direct Truncation Method for Order Reduction of Discrete Interval System”, IEEE INDICON-2013, IIT (Bombay), India, pp. 1-4, Dec.13-15, 2013.
  27. A. K. Choudhary and S. K. Nagar, “Gamma Delta Approximation for Reduction of Discrete Interval System”, International Conference on Advances in Recent Technologies in Electrical and Electronics (ARTEE-13), Bangalore, India, Elsevier, pp. 91-94, Sept. 20-21, 2013
  28. D. Kumar and S. K. Nagar, “Improved results on frequency weighted optimal Hankel norm model reduction”, 2013 9th Asian Control Conference (ASCC), pp. 1-4, 2013.
  29. D. Kumar and S. K. Nagar, Generalized frequency weighted optimal Hankel norm model reduction”, 2013 8th IEEE Conference on Industrial Electronics and Applications (ICIEA), pp. 22-25, 2013
  30. D. Kumar and S. K. Nagar, A new frequency weighted model reduction technique using balanced singular perturbation approximation”, 2013 Annual IEEE Indian Conference (INDICON), pp. 1-5, 2013.
  31. D. Kumar, S. K. Nagar and J. P. Tiwari, “Controller reduction using optimal Hankel norm approximation with guaranteed closed-loop performance”, 2012 7th IEEE Conference on Industrial Electronics and Applications (ICIEA), pp. 757-762, 2012.
  32. D. Kumar, J. P. Tiwari and S. K. Nagar, “Controller Reduction by Singular Perturbation Approximation with Guaranteed Closed-loop Performance”, 2012 7th IEEE Conference on Industrial Electronics and Applications (ICIEA), pp. 757-762, 2012.
  33. A. Hussain, A. K. Choudhary, S. K. Nagar and J. P. Tiwari, “Some Aspects of Fuzzy Logic Controller and its Application”, International Conference on Artificial Intelligence and Soft Computing (AISC 2012), IIT (BHU), Varanasi, India, 2012.
  34. A. K. Choudhary, S. K. Nagar and J. P. Tiwari, “Implementation of Fuzzy Controller to Magnetic Levitation System”, IX Control Instrumentation System Conference (CISCON-12), pp. 201-206, Nov. 16-17, 2012.
  35. A. R. Choudhary, S. K. Nagar, “Controller synthesis for the under-load tap-changing transformer problem – A timed discrete event systems approach”, International Conference on Automation, Robotics and Control Systems (ARCS), pp. 115-120, 2010.
  36. D. Kumar, S. K. Nagar, S. K. Bhardwaj, “Model order reduction of S.I.S.O. and M.I.M.O. systems based on genetic algorithm”, International Conference on Automation, Robotics and Control Systems (ARCS), pp. 97-104, 2010.
  37. S. K. Singh, S. K. Nagar, J. Pal, “Balanced realized reduced model of non-minimal system with DC gain preservation”, Proceedings of the IEEE International Conference on Industrial Technology, 4237720, pp. 1522-1527, 2006.
  38. S. K. Singh, S. K. Nagar, “BSPA based H2 / Hinfinity controller reduction”, Proceedings of the IEEE INDICON, pp. 195-198, 2004.
  39. S. K. Nagar, B. Mazhari, “A new approach to topology selection for cell-level analog circuits”. Proceedings of the IEEE International Conference on VLSI Design, 17, pp. 619-622, 2004.
  40. A. K. Sahani, S. K. Nagar, J. Pal, “Algorithm for reduced order modelling of digital controllers”, Proceedings of the IEEE International Conference on Industrial Technology, 1, pp. 753-755, 2000.
  41. S. K. Nagar, J. Pal, J. D. Sharma, “Model order reduction of digital control systems”, Singapore International Conference on Intelligent Control and Instrumentation, 637651, pp. 869-872, 1992.
S. No. Name of Student Title of Thesis Year of Award
1. Awadhesh Kumar Sahani Digital Controller Design and Reduced Order Modelling Algorithms for Linear Dynamic Systems 1997
2. Surendra Kumar Singh Balanced Realization Based Reduction Algorithms And Their Applications 2003
3. Deepak Kumar Frequency Weighted Balanced Realization based Model Reduction Algorithms 2012
4. Santosh Kumar Vipparthi Design and Enhancement of Feature Descriptors for Image Indexing and Retrieval 2014
5. Kranthi Kumar Deveerasetty Model Order Reduction of Interval Systems Using Mixed Methods 2016
6. K. Murulidhar Goud Design of Fractional Order Controller for Non-Monotonic Systems 2016
7. Shekhar Yadav Some Aspects of Intelligent Control of Nonlinear Systems 2017
8. Amit Kumar Choudhary Model Order reduction of Discrete Time Interval Systems 2017
9. Om Prakash Bharati Design of Doubly Fed Induction Generator for WECS 2018
10. Santosh Kumar Verma Design And Optimisation of Fractional Order PID Controller 2018