List of English Publication

@inproceedings{nokey,

title = {Lyapunov Functions for Singularly Perturbed Hybrid Systems with Frequent Jump Dynamics},

author = {Aneel Tawani and Hyungbo Shim},

url = {https://css.paperplaza.net/conferences/conferences/CDC21/program/CDC21_ContentListWeb_4.html},

doi = {10.1109/CDC45484.2021.9682912},

year  = {2021},

date = {2021-12-13},

urldate = {2021-12-01},

booktitle = {Proc. of 2021 IEEE 60th Conference on Decision and Control},

pages = {5382-5387},

publisher = {IEEE},

address = {Austin, Texas, USA},

abstract = {This article considers the stability analysis for a class of hybrid systems with the focus being on the frequently occurring jump dynamics. The system class is modelled as a singularly perturbed hybrid system where the singular perturbation parameter governs the frequency of jumps. Consequently, this results in a quasi steady-state system modeled by a differential equation without any jumps, and the boundary-layer system described by purely discrete dynamics. By imposing appropriate assumptions on the quasi steady-state system and the boundary-layer system, we derive results showing practical convergence to a compact attractor when the jumps occur frequently often. Our system class is motivated by the control design problem in a network of second-order continuous-time coupled oscillators, where each agent communicates the information about its position to the neighbors at discrete times. As a corollary to our main result, we show that if the information exchange between the agents and their neighbors is frequent enough, then the oscillators achieve practical consensus.},

keywords = {Hybrid system, Lyapunov function, Singular perturbation},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{LeeShim19b,

title = {Behavior of a network of heterogeneous Li´enard systems under strong output coupling},

author = {Jin Gyu Lee and Hyungbo Shim},

doi = {https://doi.org/10.1016/j.ifacol.2019.11.788},

year  = {2019},

date = {2019-09-04},

booktitle = {Proc. of 8th IFAC Symposium on Mechatronic Systems & 11th IFAC Symposium on Nonlinear Control Systems},

journal = {Proc. of 2016 IEEE 55th Conference on Decision and Control},

volume = {52},

number = {16},

pages = {256-261},

publisher = {IFAC},

address = {Vienna, Austria},

abstract = {In this paper, to participate in the understanding of a biological system, we analyze the synchronous and oscillatory behavior of coupled Liénard systems. In particular, we will consider a network of heterogeneous Liénard systems under output diffusive coupling to take into account two fundamental characteristics of a biological system. The key idea in this work is to emphasize the role of a network, which introduces an emergent behavior that each individual element approximately follows, hence making elements approximately synchronize. The intuition comes from a series of developments recently made in the name of ‘blended dynamics,’ and thus, the common philosophy of ‘blended dynamics’ approach enables us to illustrate a biological phenomenon that collective behavior is preserved even when there are some malfunctioning elements.},

keywords = {Approximate synchronization, Blended dynamics, Heterogeneous multi-agents, Internal model principle, Lienard system, Oscillations, Singular perturbation, Strong coupling},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{YunShimChang17,

title = {Singular Perturbation for Sampled-Data Systems With Fast Subsystems},

author = {Hyeonjun Yun and Hyungbo Shim and H. J. Chang

},

doi = {10.1016/j.ifacol.2017.08.1255},

year  = {2017},

date = {2017-07-12},

booktitle = {Proc. of the 20th World Congress},

pages = {8475-8480},

address = {Toulouse, France},

organization = {IFAC},

abstract = {We present a sampled-data version of the well-known Tikhonov’s theorem on singular perturbation theory. In particular, we claim that the nonlinear sampled-data systems with fast subsystems can be treated as a singularly perturbed system in a discrete-time sense. In this case, we show that the sampling period can be considered as a singular perturbation parameter. Following the nomenclature of the singular perturbation theory, we define the degenerate (DG) system and the boundary-layer (BL) system and obtain the solution of the sampled-data system as an approximation of the solutions of the lower-order subsystems. Finally, a simple example, sampled-data implementation of disturbance observer, is included to validate the theory.},

keywords = {Singular perturbation},

pubstate = {published},

tppubtype = {inproceedings}

}