Bogdan D. Ciubotaru

Scopus Publications

Derivative-free Kalman filtering for a six-wheeled rover
Beatrice M. Bălăceanu, Florin Stoican, Bogdan D. Ciubotaru, Ionela Prodan
European Journal of Control, 2025
Addressing Missing Data Challenges in Geriatric Health Monitoring: A Study of Statistical and Machine Learning Imputation Methods
Gabriel-Vasilică Sasu, Bogdan-Iulian Ciubotaru, Nicolae Goga, Andrei Vasilățeanu
Sensors, 2025
In geriatric healthcare, missing data pose significant challenges, especially in systems used for frailty monitoring in elderly individuals. This study explores advanced imputation techniques used to enhance data quality and maintain model performance in a system designed to detect frailty insights. We introduce missing data mechanisms—Missing Completely at Random (MCAR), Missing at Random (MAR), and Missing Not at Random (MNAR)—into a dataset collected from smart bracelets, simulating real-world conditions. Imputation methods, including Expectation–Maximization (EM), matrix completion, Bayesian networks, K-Nearest Neighbors (KNN), Support Vector Machines (SVMs), Generative Adversarial Imputation Networks (GAINs), Variational Autoencoder (VAE), and GRU-D, were evaluated based on normalized Mean Squared Error (MSE), Mean Absolute Error (MAE), and R2 metrics. The results demonstrate that KNN and SVM consistently outperform other methods across all three mechanisms due to their ability to adapt to diverse patterns of missingness. Specifically, KNN and SVM excel in MAR conditions by leveraging observed data relationships to accurately infer missing values, while their robustness to randomness enables superior performance under MCAR scenarios. In MNAR contexts, KNN and SVM effectively handle unobserved dependencies by identifying underlying patterns in the data, outperforming methods like GRU-D and VAE. These findings highlight the importance of selecting imputation methods based on the characteristics of missing data mechanisms, emphasizing the versatility and reliability of KNN and SVM in healthcare applications. This study advocates for hybrid approaches in healthcare applications like the cINnAMON project, which supports elderly individuals at risk of frailty through non-intrusive home monitoring systems.
The hallucination problem in Generative Artificial Intelligence: accuracy and trust in digital learning
Bogdan-Iulian CIUBOTARU
Proceedings of the International Conference on Virtual Learning, 2025
Generative Artificial Intelligence and Large Language Models: A Systematic Review of Architectures, Applications, and Future Directions
Bogdan-Iulian Ciubotaru
Proceedings 2025 25th International Conference on Control Systems and Computer Science Cscs 2025, 2025
Frailty Insights Detection System (FIDS)—A Comprehensive and Intuitive Dashboard Using Artificial Intelligence and Web Technologies
Bogdan-Iulian Ciubotaru, Gabriel-Vasilică Sasu, Nicolae Goga, Andrei Vasilățeanu, Iuliana Marin, et al.
Applied Sciences Switzerland, 2024
Frailty, known as a syndrome affecting the elderly, have a direct impact on both social well-being and body’s ability to function properly. Specific to geriatric healthcare, the early detection of frailty helps the specialists to mitigate risks of severe health outcomes. This article presents the development process of a system used to determine frailty-specific parameters, focusing on easy-to-use, non-intrusive nature and reliance on objectively measured parameters. The multitude of methodologies and metrics involved in frailty assessment emphasize the multidimensional aspects of this process and the lack of a common and widely accepted methodology as being the gold standard. After the research phase, the frailty-specific parameters considered are physical activity, energy expenditure, unintentional weight loss, and exhaustion, along with additional parameters like daily sedentary time, steps history, heart rate, and body mass index. The system architecture, artificial intelligence models, feature selection, and final prototype results are presented. The last section addresses the challenges, limitations, and future work related to the Frailty Insights Detection System (FIDS).
Explicit MPC Solution Using Hasse Diagrams: Construction, Storage and Retrieval
Ştefan S. Mihai, Florin Stoican, Bogdan D. Ciubotaru
Springer Proceedings in Mathematics and Statistics, 2024
Tube Model Predictive Control for Flexible Satellite Dynamics
Sabin Diaconescu, Florin Stoican, Bogdan D. Ciubotaru
Springer Proceedings in Mathematics and Statistics, 2024
Elastic Tube Model Predictive Control with Scaled Zonotopic Sets
Sabin Diaconescu, Florin Stoican, Bogdan D. Ciubotaru, Sorin Olaru
IEEE Control Systems Letters, 2024
Computing the explicit MPC solution in the constrained zonotope case
Florin Stoican, Ştefan S. Mihai, Martin Mönnigmann, Bogdan D. Ciubotaru
Proceedings of the IEEE Conference on Decision and Control, 2024
Solving the explicit model predictive control (MPC) problem entails enumerating a list of critical regions and their ancillary feedback laws. Unfortunately, their number and the time required to compute them increase exponentially with the problem size (state-space model dimension and length of the prediction horizon). We show that when, as it is often the case, the problem’s constraints take the form of boxes or zonotopes, the resulting feasible domain can be compactly described as a constrained zonotope. Subsequently, we investigate whether, and under which circumstances, the combinatorial structure of the constrained zonotope interpretation accelerates the computation of the explicit solution.
Distributed Control of Descriptor Networks: A Convex Procedure for Augmented Sparsity
Andrei Sperilă, Cristian Oară, Bogdan D. Ciubotaru, Şerban Sabău
IEEE Transactions on Automatic Control, 2023
For networks of systems, with possibly improper transfer function matrices, we present a design framework that enables <inline-formula><tex-math notation="LaTeX">$\\mathcal {H}_\\infty$</tex-math></inline-formula> control, while imposing sparsity constraints on the coprime factors of the controller. We propose a convex and iterative optimization procedure with guaranteed convergence to obtain distributed controllers. By exploiting the robustness-oriented nature of our proposed approach, we provide the means to obtain sparse representations of our control laws that may not be directly supported by the nominal model of the network.
Prototype Results of an Internet of Things System Using Wearables and Artificial Intelligence for the Detection of Frailty in Elderly People
Bogdan-Iulian Ciubotaru, Gabriel-Vasilică Sasu, Nicolae Goga, Andrei Vasilățeanu, Iuliana Marin, et al.
Applied Sciences Switzerland, 2023
Architecture of a Non-Intrusive IoT System for Frailty Detection in Older People
Bogdan-Iulian Ciubotaru, Gabriel-Vasilică Sasu, Nicolae Goga, Andrei Vasilateanu, Alexandru-Filip Popovici
Electronics Switzerland, 2023
Computing the explicit MPC solution using the Hasse diagram of the lifted feasible domain
Ştefan S. Mihai, Florin Stoican, Bogdan D. Ciubotaru
2023 European Control Conference Ecc 2023, 2023
On the link between explicit MPC and the face lattice of the lifted feasible domain
Ştefan S. Mihai, Florin Stoican, Bogdan D. Ciubotaru
IFAC Papersonline, 2022
Satellite micro-launcher control: An integrated adaptive-robust and nonlinear approach
Bogdan D. Ciubotaru, Andrei Sperilă, Sabin Diaconescu, Florin Stoican, Adrian M. Stoica, et al.
Control Engineering Practice, 2022
H2Output Feedback Control of Differential-Algebraic Systems
Andrei Sperila, Cristian Oara, Bogdan D. Ciubotaru
IEEE Control Systems Letters, 2022
The optimal H2 controller for generalized discrete-time systems
Andrei Sperilă, Bogdan D. Ciubotaru, Cristian Oară
Automatica, 2021
A quantitative research for determining the user requirements for developing a system to assist people with frailty
Bogdan-Iulian Ciubotaru, Vasilica-Gabriel Sasu, Andrei Vasilateanu, Nicolae Goga, Ramona Dragomir, et al.
Proceedings 2021 23rd International Conference on Control Systems and Computer Science Technologies Cscs 2021, 2021
Observations on the complexity of the explicit MPC
Florin Stoican, Stefan S. Mihai, Bogdan D. Ciubotaru
Proceedings of the IEEE Conference on Decision and Control, 2021
Extended analysis using nist methodology of sensor data entropy
UPB Scientific Bulletin Series C Electrical Engineering and Computer Science, 2021
A Quantitative Research for Determining the User Requirements for Developing a System to Detect Depression
Vasilica-Gabriel Sasu, Bogdan-Iulian Ciubotaru, Ramona Popovici, Alexandru-Filip Popovici, Nicolae Goga, et al.
2021 9th E Health and Bioengineering Conference Ehb 2021, 2021
H2 Control for Differential-Algebraic Systems
European Control Conference 2020 Ecc 2020, 2020
Fault-tolerant optimal control scheme for satellite micro-launchers
Alexandra Reitu, Andrei Sperilă, Bogdan D. Ciubotaru
IFAC Papersonline, 2020
H∞ control for differential-algebraic systems
Andrei Sperilă, Florin S. Tudor, Bogdan D. Ciubotaru, Cristian Oară
IFAC Papersonline, 2020
Analysis of classical and adaptive control algorithms for a space vehicle
Maria G. Macau, Bogdan D. Ciubotaru, Dan Stefanoiu
2019 23rd International Conference on System Theory Control and Computing Icstcc 2019 Proceedings, 2019

RECENT SCHOLAR PUBLICATIONS

Explicit MPC for the constrained zonotope case with low-rank matrix updates
SS Mihai, F Stoican, M Monnigmann, BD Ciubotaru
arXiv preprint arXiv:2511.02433 , 2025
2025
Zonotope-Based Elastic Tube Model Predictive Control
S Diaconescu, F Stoican, BD Ciubotaru, S Olaru
arXiv preprint arXiv:2509.19824 , 2025
2025
Derivative-free Kalman filtering for a six-wheeled rover
BM Bălăceanu, F Stoican, BD Ciubotaru, I Prodan
European Journal of Control, 101334 , 2025
2025
Computing the explicit MPC solution in the constrained zonotope case
F Stoican, ŞS Mihai, M Mönnigmann, BD Ciubotaru
2024 IEEE 63rd Conference on Decision and Control (CDC), 1055-1060 , 2024
2024
Citations: 1
Elastic tube model predictive control with scaled zonotopic sets
S Diaconescu, F Stoican, BD Ciubotaru, S Olaru
IEEE Control Systems Letters 8, 1343-1348 , 2024
2024
Citations: 5
Tube Model Predictive Control for Flexible Satellite Dynamics
S Diaconescu, F Stoican, BD Ciubotaru
Difference Equations, Discrete Dynamical Systems and Applications: IDCEA … , 2024
2024
Citations: 1
Explicit MPC Solution Using Hasse Diagrams: Construction, Storage
ŞS Mihai, F Stoican, BD Ciubotaru
Difference Equations, Discrete Dynamical Systems and Applications: IDCEA … , 2024
2024
Distributed control of descriptor networks: A convex procedure for augmented sparsity
A Sperilă, C Oară, BD Ciubotaru, Ş Sabău
IEEE Transactions on Automatic Control 68 (12), 8067-8074 , 2023
2023
Citations: 10
Computing the explicit MPC solution using the Hasse diagram of the lifted feasible domain
ŞS Mihai, F Stoican, BD Ciubotaru
2023 European Control Conference (ECC), 1-7 , 2023
2023
Citations: 3
Explicit MPC Solution Using Hasse Diagrams: Construction, Storage and Retrieval
ŞS Mihai, F Stoican, BD Ciubotaru
International Conference on Difference Equations and Applications, 353-369 , 2022
2022
Citations: 1
Satellite micro-launcher control: An integrated adaptive-robust and nonlinear approach
BD Ciubotaru, A Sperilă, S Diaconescu, F Stoican, AM Stoica, S Bennani
Control Engineering Practice 122, 105072 , 2022
2022
On the link between explicit MPC and the face lattice of the lifted feasible domain
ŞS Mihai, F Stoican, BD Ciubotaru
IFAC-PapersOnLine 55 (16), 308-313 , 2022
2022
Citations: 7
Observations on the complexity of the explicit MPC
F Stoican, ŞS Mihai, BD Ciubotaru
2021 60th IEEE Conference on Decision and Control (CDC), 2551-2556 , 2021
2021
Citations: 1
The optimal H2 controller for generalized discrete-time systems
A Sperilă, BD Ciubotaru, C Oară
Automatica 133, 109889 , 2021
2021
Citations: 2
H 2 Output Feedback Control of Differential-Algebraic Systems
A Sperilă, C Oară, BD Ciubotaru
IEEE Control Systems Letters 6, 542-547 , 2021
2021
ℋ 2 Control for Differential-Algebraic Systems
A Sperilă, BD Ciubotaru, C Oară
2020 European Control Conference (ECC), 627-632 , 2020
2020
Citations: 1
H∞ Control for Differential-Algebraic Systems
A Sperila, FS Tudor, BD Ciubotaru, C Oara
Proc. of the 21st IFAC World Congress, 4285-4290 , 2020
2020
Citations: 2
Fault-tolerant Optimal Control Scheme for Satellite Micro-launchers
A Reitu, A Sperilă, BD Ciubotaru
IFAC-PapersOnLine 53 (2), 4115-4120 , 2020
2020
Analysis of Classical and Adaptive Control Algorithms for a Space Vehicle
MG Măcău, BD Ciubotaru, D Ştefănoiu
2019 23rd International Conference on System Theory, Control and Computing … , 2019
2019
Fault diagnosis of a direct drive wind turbine using a bank of Goertzel filters
LI Gliga, BD Ciubotaru, H Chafouk, D Popescu, C Lupu
2019 6th International Conference on Control, Decision and Information … , 2019
2019
Citations: 6

MOST CITED SCHOLAR PUBLICATIONS

Fault detection and diagnosis using parameter estimation with recursive least squares
EM Cimpoesu, BD Ciubotaru, D Stefanoiu
2013 19th International Conference on Control Systems and Computer Science … , 2013
2013
Citations: 39
Switching solution for multiple-models control systems
C Lupu, D Popescu, B Ciubotaru, C Petrescu, G Florea
2006 14th Mediterranean Conference on Control and Automation, 1-6 , 2006
2006
Citations: 37
Fault tolerant control of the Boeing 747 short-period mode using the admissible model matching technique
B Ciubotaru, M Staroswiecki, C Christophe
IFAC Proceedings Volumes 39 (13), 819-824 , 2006
2006
Citations: 20
Industrial Automation
D Popescu, D Stefanoiu, C Lupu, C Petrescu, B Ciubotaru, C Dimon
Editura AGIR, Bucuresti , 2006
2006
Citations: 20
Industrial Process Control
D Popescu, D Stefanoiu, C Lupu, C Petrescu, B Ciubotaru, C Dimon
AGIR Press, Bucharest , 2006
2006
Citations: 18
Automatica industriala
D Popescu, D Stefanoiu, C Lupu, C Petrescu, B Ciubotaru, C Dimon
Bucuresti: Agir, 384 , 2006
2006
Citations: 17
Distributed control of descriptor networks: A convex procedure for augmented sparsity
A Sperilă, C Oară, BD Ciubotaru, Ş Sabău
IEEE Transactions on Automatic Control 68 (12), 8067-8074 , 2023
2023
Citations: 10
Comparative study of matrix Riccati equation solvers for parametric faults accommodation
BD Ciubotaru, M Staroswiecki
2009 European Control Conference (ECC), 1371-1376 , 2009
2009
Citations: 10
Industrial Automatics
D Popescu, D Stefanoiu, C Lupu, C Petrescu, B Ciubotaru, C Dimon
Ed. AGIR, Bucharest , 2006
2006
Citations: 10
A Kalman filtering approach for systems subject to parametric modeling uncertainties
AM Stoica, TV Chelaru, F Stoican, BD Ciubotaru
IFAC-PapersOnLine 52 (12), 400-404 , 2019
2019
Citations: 8
On the link between explicit MPC and the face lattice of the lifted feasible domain
ŞS Mihai, F Stoican, BD Ciubotaru
IFAC-PapersOnLine 55 (16), 308-313 , 2022
2022
Citations: 7
Fault detection and identification using parameter estimation techniques
EM Cimpoesu, BD Ciubotaru, D Stefanoiu
UPB Scientific Bulletin, Series C 76 (2), 3-14 , 2014
2014
Citations: 7
Fault diagnosis of a direct drive wind turbine using a bank of Goertzel filters
LI Gliga, BD Ciubotaru, H Chafouk, D Popescu, C Lupu
2019 6th International Conference on Control, Decision and Information … , 2019
2019
Citations: 6
Short investigation on system diagnosis regarding parameter estimation
EM Cimpoeşu, BD Ciubotaru, D Ştefănoiu
2012 1st International Conference on Systems and Computer Science (ICSCS), 1-6 , 2012
2012
Citations: 6
Modified pseudo-inverse method with generalized linear quadratic regulator for fault tolerant model matching with prescribed stability degree
BD Ciubotaru, M Staroswiecki, ND Christov
2011 50th IEEE conference on decision and control and European control … , 2011
2011
Citations: 6
Fault tolerant control of the B747 short-period mode using progressive accommodation
B Ciubotaru, M Staroswiecki
2006 IEEE Conference on Computer Aided Control System Design, 2006 IEEE … , 2006
2006
Citations: 6
Automatica Industrial; Agir: Bucharest
D Popescu, D Stefanoiu, C Lupu, B Ciubotaru, C Petrescu, C Dimon
Romania , 2006
2006
Citations: 6
Elastic tube model predictive control with scaled zonotopic sets
S Diaconescu, F Stoican, BD Ciubotaru, S Olaru
IEEE Control Systems Letters 8, 1343-1348 , 2024
2024
Citations: 5
Anytime algorithm for parametric faults accommodation under handling quality constraints
BD Ciubotaru, M Staroswiecki
IFAC Proceedings Volumes 42 (8), 887-892 , 2009
2009
Citations: 5
Model following with output feedback for fault tolerant control
EM Cimpoeşu, BD Ciubotaru, D Popescu
15th International Conference on System Theory, Control and Computing, 1-6 , 2011
2011
Citations: 4

Bogdan D. Ciubotaru

RESEARCH, TEACHING, or OTHER INTERESTS

Scopus Publications

RECENT SCHOLAR PUBLICATIONS

MOST CITED SCHOLAR PUBLICATIONS