Article
Engineering, Multidisciplinary
Yize Zhou, Jingwen Zhang, Chayan Zhu, Haohua Wang
Summary: This study introduces a rumour propagation model based on information intervention and examines the impact of information intervention mechanism on the dynamics of rumour propagation. By calculating equilibrium points and basic reproduction numbers, and exploring the dynamics of rumour propagation under optimal control in deterministic and stochastic systems. Numerical simulations are used to verify theoretical results, analyze changes in different populations, and compare the performance of deterministic and stochastic models with existing ones.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Engineering, Electrical & Electronic
Rahul Mallik, Branko Majmunovic, Soham Dutta, Gab-Su Seo, Dragan Maksimovic, Brian Johnson
Summary: This article presents a modular architecture consisting of series-connected dc-ac converters, which have been the focus of recent developments in transformerless medium-voltage applications. The architecture includes dc-ac modules containing a quadruple active bridge dc-dc converter, generating three floating dc links to feed grid-side dc-ac inverters. The implementation of such a converter module in photovoltaic systems requires a variety of controllers to achieve maximum power point tracking, dc-link regulation, and ac-side power control. The article proposes a design approach using singular perturbation theory to decompose control loops into different timescales and provides a systematic framework for parametric selection. The approach also ensures system stability when multiple modules with identical controls are connected in series across a grid. The article concludes with experimental results of three 1000-W series-connected converter modules across a stiff grid.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2023)
Article
Mathematical & Computational Biology
Yuanfei Li, Xuejiao Chen
Summary: In this paper, the authors investigate the double-diffusion perturbation equations in the presence of porous media flow. They prove that under certain constraint conditions on the initial conditions, the solutions of the perturbation equations exhibit a Saint-Venant type spatial decay. Moreover, they establish the structural stability of the double-diffusion perturbation equations based on the spatial decay bound.
MATHEMATICAL BIOSCIENCES AND ENGINEERING
(2023)
Article
Mathematics, Applied
Jingnan Wang, Yanqiao Zhang
Summary: This paper establishes two immunotherapy antitumor models using the methods of killing tumors and impulsive differential equations, and analyzes the global stability conditions under immunotherapy and the influence of impulsive perturbation on the inherent oscillation of tumors. It also studies the effects of combining radiotherapy with immunotherapy on antitumor, including the threshold value of stability conditions in the mixed combination treatment.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2022)
Article
Automation & Control Systems
Wei Kang, Gang Qin, Jun Cheng, Huaicheng Yan, Iyad Katib, Jinde Cao
Summary: This paper proposes a security control method for a discrete-time switched power system using a probabilistic event-triggered protocol, which effectively optimizes network resource utilization and improves system security and stability under multi-strategy deception attacks.
JOURNAL OF THE FRANKLIN INSTITUTE-ENGINEERING AND APPLIED MATHEMATICS
(2023)
Article
Astronomy & Astrophysics
Almendra Aragon, Ramon Becar, P. A. Gonzalez, Yerko Vasquez
Summary: This study examines the propagation of fermionic fields in the background of Schwarzschild-de Sitter black holes and finds anomalous decay rate behavior and fine structure related to the coupling between chirality and the mass of the field.
Article
Engineering, Aerospace
Jing Chang, Roeland De Breuker, Xuerui Wang
Summary: This article reveals that existing sensor-based nonlinear fault-tolerant control methods, including incremental nonlinear dynamic inversion control, cannot guarantee closed-loop stability when the control direction is unknown, regardless of which perturbation compensation technique (adaptive, disturbance observer, sliding-mode) is implemented. Therefore, this article proposes a Nussbaum function-based adaptive incremental control framework for nonlinear dynamic systems with partially or completely unknown control effectiveness. Its effectiveness is proven in the Lyapunov sense and verified through numerical simulations of an aircraft attitude tracking problem in the presence of various uncertainties and faults.
IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS
(2023)
Article
Automation & Control Systems
Chunyu Yang, Fanyi Meng, Hengjin Zhang, Jianguo Zhao, Hai Wang, Linna Zhou
Summary: This article investigates the optimal coordinated control problem of rigidly connected permanent magnet synchronous motor (PMSM) systems to enhance speed tracking and torque synchronization performance. A novel optimal coordinated control scheme is proposed by combining the conventional master-slave control structure and the linear-quadratic regulator control strategy. A composite suboptimal coordinated controller is devised based on the inherent two-time-scale characteristics. Simulation and experimental studies validate the effectiveness of the proposed method.
IEEE-ASME TRANSACTIONS ON MECHATRONICS
(2023)
Article
Energy & Fuels
Mingmao Hu, Feng Yang, Yi Liu, Liang Wu
Summary: This paper proposes an improved finite control set model for permanent magnet synchronous motors, establishes a new hyperlocal model, designs a model-free finite control set predictive current controller, and corrects prediction errors by introducing a current error correction factor. The stability of the observer is demonstrated through Lyapunov theory, proving system robustness during parameter perturbation.
Article
Automation & Control Systems
Sagar V. Patil, Yu-Chen Sung, Michael G. Safonov
Summary: The Battistelli-Hespanha-Mosca-Tesi (BHMT) adaptive reset switching algorithm has been enhanced to allow bumpless transfer and control of nonlinear time-varying plants using a broad class of two-degree-of-freedom nonlinear time-varying controllers. The performance, including stability and exponential stability, has been proven given the lambda-feasibility of the adaptive stabilization problem.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2022)
Article
Engineering, Electrical & Electronic
Jinghan Li, Jun Zhao
Summary: This paper investigates bumpless transfer control for a certain type of switched linear systems. A hierarchical switching strategy is proposed to address the bumpless transfer control problem. The key idea is to design two controllers for each subsystem, as the conventional design with a single controller often fails to achieve stability and satisfactory bumpless transfer performance simultaneously. The upper level switching determines the active subsystem, while the lower level switching selects which controller among the two controllers of the active subsystem to be activated. The dual design of switching and controllers ensures asymptotic stability and satisfactory bumpless transfer performance for the closed-loop switched system. Numerical examples are provided to demonstrate the effectiveness of the proposed methods.
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS
(2023)
Article
Biophysics
A. Weber, D. Friemert, U. Hartmann, G. Epro, J. Seeley, J. Werth, P. Nickel, K. Karamanidis
Summary: This study examined adaptation in gait stability and interlimb transfer during a virtual obstacle avoidance task. Findings showed that toe clearance decreased and MoS increased with repeated practice, suggesting limited transferability of gait adaptations between limbs.
JOURNAL OF BIOMECHANICS
(2021)
Article
Automation & Control Systems
Panagiotis Petsagkourakis, William P. Heath, Joaquin Carrasco, Constantinos Theodoropoulos
Summary: The conditions for robust input-output stability of barrier-based model predictive control for linear systems with linear and convex nonlinear constraints were established using integral quadratic constraints (IQCs). IQCs were utilized to determine sufficient conditions for global closed-loop stability, even in the presence of unstructured model uncertainty. The development of IQCs with static and dynamic multipliers, along with appropriate convex searches for the multipliers, was demonstrated effective through a numerical example.
IEEE TRANSACTIONS ON AUTOMATIC CONTROL
(2021)
Article
Automation & Control Systems
Yaxing Ren, Ruotong Wang, Saqib Jamshed Rind, Pingliang Zeng, Lin Jiang
Summary: This paper proposes a sensorless speed controller for IM based on speed and perturbation estimation and compensation. It includes the design of state and perturbation observers to estimate the flux and speed states and related perturbation terms, and the design of an output feedback, speed sensorless nonlinear adaptive controller for IM. The effectiveness of the controller is verified through simulation and experiment tests.
CONTROL ENGINEERING PRACTICE
(2022)
Article
Biotechnology & Applied Microbiology
Cezar Mezher, Tarique Siragy, Julie Nantel
Summary: The study evaluated the effect of arm swing on postural control and stability, finding that active arm swing increased trunk velocity variability and peak values, as well as step length, step time, and stability boundary variability. Walking on a rocky surface increased trunk kinematics variability and peak values, as well as step width and reduced step time. The results suggest that individuals adopt a cautious gait to mitigate the destabilizing effects of active arm swing and walking on rocky surfaces in order to maintain dynamic stability.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2021)
Article
Biophysics
Nathan D. Camarillo, Rafael Jimenez-Silva, Frances T. Sheehan
Summary: This article discusses the statistical dependence between multiple measurements from the same participant and provides recommendations for using these measurements when they are not independent.
JOURNAL OF BIOMECHANICS
(2024)
Article
Biophysics
J. Huet, A. -S. Boureau, A. Sarcher, C. Cornu, A. Nordez
Summary: Standard compression in freehand 3D ultrasound induces a bias in volume calculations, but minimal compression and gel pad methods have similar results. With a trained examiner and precautions, the bias can be minimized and become acceptable in clinical applications.
JOURNAL OF BIOMECHANICS
(2024)
Article
Biophysics
C. Lariviere, A. H. Eskandari, H. Mecheri, F. Ghezelbash, D. Gagnon, A. Shirazi-Adl
Summary: Recent developments in musculoskeletal modeling have focused on model customization. Personalization of the spine profile may affect estimates of spinal loading and stability. This study investigates the biomechanical consequences of changes in the spinal profile and finds that personalizing the spine profile has medium to large effects on trunk muscle forces and negligible to small effects on spinal loading and stability.
JOURNAL OF BIOMECHANICS
(2024)
Article
Biophysics
Luke T. Mattar, Arash B. Mahboobin, Adam J. Popchak, William J. Anderst, Volker Musahl, James J. Irrgang, Richard E. Debski
Summary: Exercise therapy fails in about 25.0% of cases for individuals with rotator cuff tears, and one reason for this failure may be the inability to strengthen and balance the muscle forces that keep the humeral head in the correct position. This study developed computational musculoskeletal models to compare the net muscle force before and after exercise therapy between successfully and unsuccessfully treated patients. The study found that unsuccessfully treated patients had less inferiorly oriented net muscle forces, which may increase the risk of impingement.
JOURNAL OF BIOMECHANICS
(2024)
Article
Biophysics
Natsuki Sado, Takeshi Edagawa, Toshihide Fujimori, Shogo Hashimoto, Yoshikazu Okamoto, Takahito Nakajima
Summary: The existing methods for predicting hip and lumbosacral joint centres in Japanese adults are biased and differ between sexes. We propose new regression equations that consider soft-tissue thickness, sex differences, and a height-directional measure, and validate them using leave-one-out cross-validation.
JOURNAL OF BIOMECHANICS
(2024)
Article
Biophysics
Peimin Yu, Xuanzhen Cen, Qichang Mei, Alan Wang, Yaodong Gu, Justin Fernandez
Summary: This study aimed to explore the intra-foot biomechanical differences among individuals with chronic ankle instability (CAI), copers, and healthy individuals during dynamic tasks. The study found that copers and CAI individuals had smaller dorsiflexion angles and copers presented a more eversion position compared to healthy participants. Copers also had greater dorsiflexion angles in the metatarsophalangeal joint and more inversion moments in the subtalar joint during certain tasks. These findings can help in designing interventions to restore ankle joint functions in CAI individuals.
JOURNAL OF BIOMECHANICS
(2024)
Article
Biophysics
Jon Skovgaard Jensen, Anders Holsgaard-Larsen, Anders Stengaard Sorensen, Per Aagaard, Jens Bojsen-Moller
Summary: This study investigates the biomechanical effects of robot-assisted body weight unloading (BWU) on gait patterns in healthy young adults. The results show that dynamic robot-assisted BWU enables reduced kinetic requirements without distorting biomechanically normal gait patterns during overground walking.
JOURNAL OF BIOMECHANICS
(2024)