Methodology to compute the speed of pumps that fit the hydrodynamic levels in a well field by Georgescu Sanda-Carmen, Găitănaru Ștefan-Dragoș, Iancu Iulian, Miron Călin Ioan, Georgescu Andrei-Mugur

“…The method is exemplified for a case study in Bucharest − a small well field, for which hydrogeological data are available. The nonlinear system of equations that defines the hydraulic system operation is solved in MATLAB for the stationary flow regime attained after reaching constant hydrodynamic levels in all wells. …”
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A Hybrid Renewable Sources Implementation for a DC Microgrid with Flatness-Nonlinear Control to Achieve Efficient Energy Management Strategy by Furqan A. Abbas, Adel A.Obed, Ammar Alhasiri, Salam J. Yaqoob

“…Taking into account the slow dynamic response of the FC, the SC provides transient periods under various conditions to maintain stability of the system. Because of the nonlinear system's behavior, differential flatness-based control has been applied mainly in nonlinear systems where the number of variables to the outputs is reduced with a robust control system established through inherited parameter reductions and equality constraints due to the system trajectories (x, u) is straightforwardly estimated from flat output trajectories y and their derivatives without any differential equation integration. …”
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Impact of the nonlinear thermal radiation on the Arrhenius activation energy of tangent hyperbolic micropolar hybrid nanofluid flow across an extending surface by MD. Shamshuddin, Balasani Srinitha, S.O. Salawu, M. Sunder Ram

“…The energy transmission and fluid flow are mathematically specified using a coupled nonlinear system of PDEs (partial derivative equations). …”
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ESTABLISHED MODES AND STATIC CHARACTERISTICS OF THREE-PHASE ASYNCHRONOUS MOTOR POWERED WITH SINGLE PHASE NETWORK by V. S. Malyar, V. V. Malyar

“…In order to perform it, the original nonlinear differential equations are algebraized by approximating the variables with the use of cubic splines. The resulting nonlinear system of algebraic equations is a discrete analogue of the initial system of differential equations. …”
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Disturbance Rejection in a One-Half Semiactive Vehicle Suspension by means of a Fuzzy-H∞ Controller by L. C. Félix-Herrán, Driss Mehdi, José de Jesús Rodríguez-Ortiz, Victor H. Benitez, Ricardo A. Ramirez‐Mendoza, Rogelio Soto

“…The herein contribution resides in the development and computation of an H∞ controller with parallel distributed compensation (PDC) designed from a highly nonlinear system modelled via the Takagi–Sugeno (T-S) fuzzy approach. …”
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Predefined-Time <italic>H</italic> _&#x221E; Cooperative Control for Multi-Robot Systems Based on Adjustable Prescribed Performance Control and Adaptive Command Filter by Haitao Liu, Weichen Li, Xin Huang, Xuehong Tian, Qingqun Mai

“…Third, the predefined-time <inline-formula> <tex-math notation="LaTeX">$H_{\infty } $ </tex-math></inline-formula> control theory is developed to guarantee that the nonlinear system has global predefined-time stabilization and that the <inline-formula> <tex-math notation="LaTeX">$L_{2}$ </tex-math></inline-formula> gain is less than <inline-formula> <tex-math notation="LaTeX">$\gamma $ </tex-math></inline-formula>. …”
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Exact controllability for systems describing plate vibrations. A perturbation approach by Bournissou, Megane, Ervedoza, Sylvain, Tucsnak, Marius

“…This leads, via a fixed-point method, to our second main result: the nonlinear system described by the von Kármán plate equations is locally exactly controllable around any stationary state defined by a real analytic function. …”
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Novel numerical and artificial neural computing with experimental validation towards unsteady micropolar nanofluid flow across a Riga plate by Muhammad Bilal, F. Maiz, Muhammad Farooq, Hijaz Ahmad, Mohammad Khalid Nasrat, Hassan Ali Ghazwani

“…The fluid flow has been expressed in the form of a nonlinear system of PDEs (partial differential equations), which are reduced into the non-dimensional form of ordinary differential (ODEs) by employing the similarity transformation approach. …”
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Further Analysis of the Passive Dynamics of the Compass Biped Walker and Control of Chaos via Two Trajectory Tracking Approaches by Essia Added, Hassène Gritli, Safya Belghith

“…The dynamic walking of the compass-gait walker is modeled by an impulsive hybrid nonlinear system. This impulsive hybrid nature is considered very complex as it can generate unwanted phenomena such as chaos and bifurcations. …”
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Rub-Impact Force Induces Periodic, Quasiperiodic, and Chaotic Motions of a Controlled Asymmetric Rotor System by N. A. Saeed, Emad Mahrous Awwad, Ali Maarouf, Hassan M. H. Farh, Fahd A. Alturki, Jan Awrejcewicz

“…Firstly, the obtained model is treated as a weakly nonlinear system using perturbation analysis to obtain the slow-flow modulating equations when neglecting the rub and impact forces. …”
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Thermal Convective Instabilities and Chaos in a Rotating Hybrid Nanofluid Layer with Cattaneo–Christov Heat Flux Model by Sèmako Justin Dèdèwanou, Adjimon Vincent Monwanou, Aimé Audran Koukpémèdji, Amoussou Laurent Hinvi, Clément Hodévèwan Miwadinou, Jean Bio Chabi Orou

“…This approximation allowed us to find a novel six-dimensional nonlinear system depending on the parameters of the base fluid and the thermophysical properties of the hybrid nanofluid that can be reduced to five, four, or three dimensions when we tend some parameters to zero. …”
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Community behavior for mathematical model of coronavirus disease 2019 (COVID-19) by M. Ramli, M. Mukramati, M. Ikhwan, H. Hafnani

“…The model-generated equation system is a nonlinear system of differential equations. The developed model is examined by determining the equilibrium point and the basic reproduction number.FINDINGS: The model resulted an asymptotically stable disease-free equilibrium and endemic equilibrium. …”
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A Quasi-Steady State Model of a Singularly Perturbed Wind Turbine with an Induction Generator and Nonlinear Frictions: A Bond Graph Approach by Aaron Padilla-Garcia, Gilberto Gonzalez-Avalos, Noe Barrera-Gallegos, Gerardo Ayala-Jaimes

“…The modelling in bond graph of a class of nonlinear systems with singular perturbations is presented. …”
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W-Stability of Multistable Nonlinear Discrete-Time Systems by Zhishuai Ding, Guifang Cheng, Xiaowu Mu

“…Efimov, the estimates of solution and the Lyapunov stability theorem and converse theorem are proposed for multi-stable discrete-time nonlinear systems.…”
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Some results on stability of difference systems by Xiao-Song Yang, Ping Zhou

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Exponential Stability of Switched Positive Homogeneous Systems by Dadong Tian, Shutang Liu

“…This paper studies the exponential stability of switched positive nonlinear systems defined by cooperative and homogeneous vector fields. …”
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Novel Stability Criteria of Nonlinear Uncertain Systems with Time-Varying Delay by Yali Dong, Shengwei Mei, Xueli Wang

“…The problem of robust exponential stabilization for dynamical nonlinear systems with uncertainties and time-varying delay is considered in the paper. …”
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Adaptive Control Using Neural Networks and Approximate Models for Nonlinear Dynamic Systems by Khadija El Hamidi, Mostafa Mjahed, Abdeljalil El Kari, Hassan Ayad

“…In this research, a comparative study of two recurrent neural networks, nonlinear autoregressive with exogenous input (NARX) neural network and nonlinear autoregressive moving average (NARMA-L2), and a feedforward neural network (FFNN) is performed for their ability to provide adaptive control of nonlinear systems. Three dynamical nonlinear systems of different complexity are considered. …”
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Periodic Solutions for a System of Difference Equations by Shugui Kang, Bao Shi

“…This paper deals with the second-order nonlinear systems of difference equations, we obtain the existence theorems of periodic solutions. …”
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On the Coupling of the Homotopy Perturbation Method and New Integral Transform for Solving Systems of Partial Differential Equations by E. E. Eladdad, E. A. Tarif

“…This combination allows to obtain analytic and numerical solutions for linear and nonlinear systems of partial differential equations.…”
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