no code implementations • 9 Jun 2023 • Ran Tao, Hunmin Kim, Hyung-Jin Yoon, Wenbin Wan, Naira Hovakimyan, Lui Sha, Petros Voulgaris
To include this new safety concept in control problems, we formulate a feasibility maximization problem aiming to maximize the feasibility of the primary and alternative missions.
no code implementations • 28 Dec 2022 • Hyung-Jin Yoon, Hamidreza Jafarnejadsani, Petros Voulgaris
We propose a multi-level stochastic optimization framework that monitors an attacker's capability of generating the adversarial perturbations.
no code implementations • 15 Sep 2022 • Hyung-Jin Yoon, Petros Voulgaris
Due to recent climate changes, we have seen more frequent and severe wildfires in the United States.
no code implementations • 23 Jun 2022 • Chuyuan Tao, Hyung-Jin Yoon, Hunmin Kim, Naira Hovakimyan, Petros Voulgaris
In this paper, we utilize Stochastic Control Barrier Functions (SCBFs) constraints to limit sample regions in the sample-based algorithm, ensuring safety in a probabilistic sense and improving sample efficiency with a stochastic differential equation.
no code implementations • 28 Nov 2021 • Alissa Chavalithumrong, Hyung-Jin Yoon, Petros Voulgaris
As wildfires are expected to become more frequent and severe, improved prediction models are vital to mitigating risk and allocating resources.
no code implementations • 12 Nov 2021 • Chuyuan Tao, Hunmin Kim, HyungJin Yoon, Naira Hovakimyan, Petros Voulgaris
For a nonlinear stochastic path planning problem, sampling-based algorithms generate thousands of random sample trajectories to find the optimal path while guaranteeing safety by Lagrangian penalty methods.
no code implementations • 25 Oct 2021 • Theodoros Mamalis, Dusan Stipanovic, Petros Voulgaris
Theoretical results show accelerated almost-sure convergence rates of Stochastic Gradient Descent in a nonconvex setting when using an appropriate stochastic learning rate, compared to a deterministic-learning-rate scheme.
no code implementations • 20 Oct 2021 • Theodoros Mamalis, Dusan Stipanovic, Petros Voulgaris
In this work, multiplicative stochasticity is applied to the learning rate of stochastic optimization algorithms, giving rise to stochastic learning-rate schemes.
no code implementations • 30 Sep 2021 • Hyungsoo Kang, Hyung-Jin Yoon, Venanzio Cichella, Naira Hovakimyan, Petros Voulgaris
This paper presents a time-coordination algorithm for multiple UAVs executing cooperative missions.
no code implementations • 25 Sep 2021 • Wenbin Wan, Hunmin Kim, Naira Hovakimyan, Petros Voulgaris
In this paper, a constrained attack-resilient estimation algorithm (CARE) is developed for stochastic cyber-physical systems.
no code implementations • 9 May 2021 • Hyung-Jin Yoon, Hamidreza Jafarnejadsani, Petros Voulgaris
While adversarial neural networks have been shown successful for static image attacks, very few approaches have been developed for attacking online image streams while taking into account the underlying physical dynamics of autonomous vehicles, their mission, and environment.
no code implementations • 27 Mar 2021 • Hunmin Kim, HyungJin Yoon, Wenbin Wan, Naira Hovakimyan, Lui Sha, Petros Voulgaris
To incorporate this new safety concept in control problems, we formulate a feasibility maximization problem that adopts additional (virtual) input horizons toward the alternative missions on top of the input horizon toward the primary mission.
no code implementations • 4 Aug 2020 • Yanbing Mao, Yuliang Gu, Naira Hovakimyan, Lui Sha, Petros Voulgaris
Due to the high dependence of vehicle dynamics on the driving environments, the proposed Simplex leverages the finite-time model learning to timely learn and update the vehicle model for $\mathcal{L}_{1}$ adaptive controller, when any deviation from the safety envelope or the uncertainty measurement threshold occurs in the unforeseen driving environments.