Nabil Derbel

• Docteur d'Etat
• Professor (Full) at University of Sfax

Medical image classification is essential for diagnosing and treating serious diseases like lung and brain cancers since early detection of these complex formations improves patient outcomes. Current methods misclassify because they cannot catch subtle patterns and large-scale features. We solved this challenge with the Multiscale Transformer-enhan...

Rehabilitation robots, particularly lower-limb exoskeletons, are transforming healthcare by assisting individuals with mobility impairments. This study introduces a novel Sliding Mode Control (SMC) system based on a fractional-order reaching law, designed to enhance control performance and robustness. The proposed approach effectively manages the e...

The International Conference on Fractional Calculus and Applications is a prestigious event that serves as a platform for researchers, scientists, and practitioners to exchange ideas and explore the latest advancements in the field of fractional calculus. The conference aims to foster collaboration and innovation in this rapidly evolving field. Our...

Electric vehicles demand efficient and robust motor control to maximize range and performance. This paper presents an innovative adaptive fractional-order sliding mode (FO-SM) control approach tailored for Direct Torque Control with Space Vector Modulation (DTC-SVM) applied to induction motor drives. This approach tackles the challenges of paramete...

This paper examines the formulation and implementation of a neuro-controller for the excitation system of synchronous generators in a Single-Machine Infinite Bus (SMIB) power system. The SMIB model is employed as a fundamental model of a power system, thereby facilitating the assessment and comparison of disparate control strategies with the object...

The present paper proposes the use of fractional derivatives in the definition of sliding function, giving a new mode control applied to induction motor drives in electric vehicle (EV) applications. The proposed Fractional-Order Sliding Mode Direct Torque Control-Space Vector Modulation (FOSM-DTC-SVM) strategy aims to address the limitations of con...

This work presents a new fuzzy logic parameter tuning-based fractional order sliding mode control (F-FOSMC) strategy for the trajectory tracking of robotic systems. The primary objective is to achieve an optimal control compromise seeking to minimize energy consumption for required motions, all while increasing both accuracy and rapidity of the tra...

The stability of the power system is important for ensuring the power grid's reliable operation. Traditional stability analysis and stabilization methods have limitations in handling the complexity and nonlinearity of modern power systems. The combination of artificial neural network (ANN)based approaches holds particular promise for power system s...

In this paper, an Optimal Fractional Order proportional derivative controller (OFOPD) has been proposed to track the desired traj ectories and to improve the performance of of Micro-Electro-Mechanical System (MEMS) gyroscope. particle swarm optima optimization algorithm (PSO) has been used to tune the design parameters of FOPD controller. A set of...

Abstract: The escalating prevalence of renewable energy, particularly solar energy, is on a rapid incline, not solely within developed nations, but also evident in oil-producing countries. Various challenges confront photovoltaic systems, with fault detection emerging as a pivotal issue. Artificial intelligence (AI) stands out as a prominent contem...

This paper provides a comprehensive analysis of a grid-connected hybrid microgrid system that seamlessly integrates renewable energy sources, encompassing wind generators, solar arrays, and Fuel Cells (FCs). Emphasis is placed on the pivotal role of power electronic converters in optimizing control and energy management strategies for these diverse...

In this paper , a three degrees of freedom lower limb exoskeleton is modeled in case of contacting with ground . The dynamic equations for lower limb exoskeleton in reduced order form are derived based on augmented Lagrange equations which include Lagrange multiplier and Jacobian vectors. The controller is constructed using fractional order calculu...

In this study, a lower limb rehabilitation exoskeleton (LLRE) contacting with floor with uncertainties and parameter variations has been controlled using a sliding mode controller (SMC). The dynamic equations for the lower limb rehabilitation exoskeleton in case of contacting with floor in reduced order form have been derived using augmented Lagran...

This paper presents an advanced control strategy based on Fractional-Order Sliding Mode Control (FO-SMC), which introduces a robust solution to significantly improve the reliability of robotic manipulator systems and increase its control performance. The proposed FO-SMC strategy includes a two-key term-based Fractional Sliding Function (FSF) that p...

In this paper, a leader-follower-based cooperative and formation flight control is designed for a group of quadrotors using new forms of fractional sliding mode control (FSMC) strategy accompanied by the potential field algorithm. The FSMC strategy is employed as an inner controller to stabilize each individual UAV quadrotor while the potential fie...

Fractional order calculus (FOC) uses arbitrary order operations in differentiation and integration. Previously, the absence of methods to solve fractional differential equations limited the application of fractional order calculus. However, with the development of new methods, FOC is now applicable in various fields and has been utilized to enhance...

span lang="EN-US">Variable load on the station refers to the fluctuating load on a power plant due to erratic consumer demands. It is known to have an effect on the performance of power system stabilizers, particularly in damping inter-area oscillation. This paper examines how two power system stabilizer (PSS) models and various load conditions aff...

This chapter presents a non-singular terminal super-twisting control (NTSTC) for the problem of trajectory tracking a lower limb rehabilitation exoskeleton with uncertainties in parameters. The modeling of the lower limb rehabilitation exoskeleton has been implemented in the case of contact with the ground. The augmented Lagrange equations with Lag...

One of the major challenges facing photovoltaic (PV) systems is fault detection. Artificial intelligence (AI) is one of the main popular techniques used in error detection due to its ability to extract signal and image features. In this paper, a deep learning approach based on convolutional neural network (CNN) and internet of things (IoT) technolo...

Inductive wireless power transfer is a promising technology for powering smart wearable devices. The spiral coil shape is widely used in wireless power transfer applications. Nevertheless, during the coil design process, there are many challenges to overcome considering all the design constraints. The most important is to determine the optimal coil...

In the decision-making systems, sensors data are often affected by diversity types of imperfections which significantly reduce system performance. Thus, data quality assessment has become a primordial step in data learning process. In this work, feature quality assessment approach is used to select only useful and reliable information from those de...

In this paper, an Interval Type 2 Fuzzy Adaptive Backstepping Sliding Mode Controller (IT2FABSMC) is proposed for nonlinear unknown systems. The proposed approach is a combination of the interval type 2 fuzzy logic control (IT2FLC), the sliding mode control (SMC) and the Backstepping control (BC), which inherits the benefits of these three methods....

The existence of a Lower limb Rehabilitation exoskeleton as an excellent solution for rehabilitation of lower limbs of stroke patients has been increased in last two decades. One of the fundamental issue in works of rehabilitation robotic devices is the modeling and controlling of lower limb Rehabilitation using suitable and efficient methods. In t...

Multi-Input Converters (MIC) are an advancing technology suitable for sustainable energies, due to its ability to incorporate several Renewable Energy Sources (RES). Various structures and topologies of DC–DC converters are developed recently to ensure the highest performances of hybrid RES. The MIC are a typical coupling system which has several o...

Derived Hench bioactive glass (BaG) containing boron (B) is explored in this work as it plays an important role in bone development and regeneration. B was also found to enhance BaG dissociation. However, it is only possible to incorporate a limited amount of B. To increase the amount of B in BaG, bioactive borosilicate glasses (BaG-Bx) were fabric...

With continuous increase in the number of students enrolled in universities, e-learning has become an urgent necessity in modern education systems. However, applied programs face challenges in adopting this type of learning because of their need for laboratories and training workshops. With the advancement in computers and wireless communications t...

In this article, a lower limb exoskeleton (LLE) under contacting constrained motion has been modelled using augmented Lagrange equations which include Lagrange multiplier and Jacobian vectors. A sliding mode Controller optimized by the grey Wolf optimization algorithm has been used for controlling (LLE) in the case of constrained motion with uncert...

Deoxyribonucleic Acid (DNA) coding technology is a new research field developed by the combination of computer science and molecular biology, that has been gradually applied in the field of image encryption in recent years. Furthermore, sensitivity to initial conditions, pseudo-random properties, and state ergodicity of coupled chaotic maps can hel...

In this work, a lower limb exoskeleton with uncertainties and external disturbances under constrained motion has been controlled by developing a model-free adaptive optimal fractional-ordersuper-twisting sliding mode (AOFSTSM) controller. Contrary to popular existing modeling methods, the modeling of the lower limb exoskeleton has been accomplished...

The load on a power station varies from time to time due to uncertain demands of the consumers and is known as variable load on the station. Also it is known to have an effect on the performance of a power system stabilizer while damping inter-area oscillation. In this paper conventional lead lag PSS and PSS2B are assessed on real case studies; Pee...

This paper describes an energy management strategy for a DC microgrid that utilizes a hybrid renewable energy system (HRES) composed of a photovoltaic (PV) module, a wind turbine based on a permanent magnetic synchronous generator (PMSG), and a battery energy storage system (BESS). The strategy is designed to provide a flexible and reliable system...

In this article, a real case of a one MW PV substation design problem is described. The impact of the tolerances of power components (mainly inductors and capacitors) on the design is highlighted through two studies using two different control strategies that are selective harmonic elimination (SHE) and selective harmonic modulation (SHM). The obta...

Monitoring changes in edema-associated intracranial pressure that complicates trauma or surgery would lead to improved outcomes. Implantable pressure sensors have been explored, but these sensors require post-surgical removal, leading to the risk of injury to brain tissue. The use of biodegradable implantable sensors would help to eliminate this ri...

Dynamic Sylvester equation (DSE) problems have drawn a lot of interest from academics due to its importance in science and engineering. Due to this, the quest for the quaternion DSE (QDSE) solution is the subject of this work. This is accomplished using the zeroing neural network (ZNN) technique, which has achieved considerable success in tackling...

Fractional order Controllers have been used in several industrial cases to achieve better performance of the systems. This paper proposes a Fractional Order Proportional Integral Derivative (FOPID) controller. It is synthesized using Oustaloup approximation, and its parameters are tuned using the Genetic Algorithm (GA) optimization method. The aim...

Monitoring changes in edema-associated intracranial pressure that complicates trauma or surgery would lead to improved outcomes. Implantable pressure sensors have been explored, but, these sensors require post-surgical removal leading to risks of injury to brain tissue. Biodegradable implantable sensors would eliminate the risks while providing sen...

Rehabilitation devices perform nowadays suitable and excellent treatment for stroke patients. A Lower limb exoskeleton as a type of Rehabilitation devices has become the most known solution for lower limb rehabilitation of stroke patients. The essential part on lower limb exoskeleton work is to model and control it using a suitable modeling method...

Bioimpedance spectroscopy (BIS) is an advanced measurement method for providing information on impedance changes at several frequencies by injecting a low current into a device under test and analyzing the response voltage. Several methods have been elaborated for BIS measurement, calculating impedance with a gain phase detector (GPD), IQ demodulat...

Background and Objectives: With the progress of digitalization, electrocardiograms (ECGs) are increasingly measured by embedded and portable devices, which may lead to significant degradation of signal quality due to noise and artifacts. This leads to the necessity of signal quality assessment before ECG interpretation. Especially, if the ECG train...

In this paper, we propose tensorbased methods for identifying nonlinear Parallel- Cascade Wiener (PCW) systems. Parameters of linear subsystems are first estimated using an approach based on the PARAFAC decomposition of the associated pth-order Volterra kernel. This approach consists in applying the Alternating Least Squares (ALS) algorithm. Then t...

In this chapter, some preliminaries on unknown input observers are given. Furthermore, the development of discontinuous observers and the methods in which they are designed are introduced. The final parts of the chapter are dedicated to the sliding mode observers design.KeywordsLinear systemObserversObserver designSliding mode

In this chapter, new results on the fault estimation problem for nonlinear One-Sided Lipschitz systems are presented. Both Integer-order systems and Fractional-order systems are investigated. First, using an original and advantageous fault modeling, an adaptive estimation strategy of component faults and actuator faults for Integer-order One-Sided...

In this chapter, new results on the state estimation problem for fractional-order systems are presented. First, a robust observer scheme for a class of linear fractional systems with matched uncertainties is proposed. Then, a novel observer design for nonlinear fractional-order systems is given. This observer is applied for both nonlinear Lipschitz...

In this chapter, an overview of fractional-order systems, nonlinear systems and observer-related queries is given. To begin with, fractional-order systems are introduced, and a state of the art in relation with these systems in the control theory is given. Then, different classes of nonlinear systems are presented, with a literature survey on the o...

In this chapter, an overview of Observers and Observability is given. To begin with, a general introduction is introduced then, observers and Observability for continuous-time linear systems is given. Finally, some observers design for certain fractional order systems is presented.

In this chapter, new results on the observer-based control problem for fractional-order systems are presented. The two control philosophies, which are the “stabilization” and the “model-reference control”, are investigated. First, dealing with the stabilization problem, an adaptive stabilization scheme for a class of uncertain nonlinear fractional...

Oversampling methods are among the most widely used methods to solve imbalanced data analysis due to their simplicity and flexibility. Multi‐class imbalanced problems involve critical issues related to synthetic samples and corresponding consequences on the classification results. The over‐fitting phenomenon, the overlapping regions between classes...

Hand sign recognition is gaining importance in human-human and in human-machine communication and interaction. Electrical Impedance Tomography (EIT) is thereby very interesting as it provides information on impedance changes in depth of the section of the arm, which infers muscle contractions. This paper introduces an EIT imaging system for hand si...

Iris recognition is a new technology that ensures a high level of security which refers to the automatic recognition of individuals based on their iris characteristics. Due to its stability and high level of discrimination, the iris is the most effective biometric modality for large-scale identification and verification systems. To build up an iris...

Biometrics are attracting widespread interest due to the increasing need for systems security everywhere. Researchers contributed to this field by applying various biometric modalities such fingerprint, face and iris recognition. In this chapter, a new recognition biometric system based on ECG signal is proposed. One of the main issues that could f...

The book highlights recent developments in the field of biomedical systems covering a wide range of technological aspects, methods, systems and instrumentation techniques for diagnosis, monitoring, treatment, and assistance. Biomedical systems are becoming increasingly important in medicine and in special areas of application such as supporting peo...

Electrical Bioimpedance Spectroscopy (BIS) is an interesting method for assessing the state or composition of human organs and various types of biological tissues in-vivo in both clinical and research applications as well as in-vitro. The non-invasiveness of this method, its manifold applicability and adaptability make it suitable for usability as...

Mobility deficiency is one of the main impairments for children with Cerebral Palsy (CP). Various approaches and techniques are used for rehabilitation purposes in order to improve the life quality and the autonomy of these young patients. Nowadays, beyond conventional techniques, such as manual stretching and massage, robotic-based gait training t...

This chapter involves the design and the implementation of an intelligent control method of an electric wheelchair for several disables persons using technologies derived from mobile robotics. The main objective of this work is to improve the performance of the wheelchair which is controlled by the brain without requirements of any physical feedbac...

This paper shows a comparison between the analytical design of a photovoltaic power station filter and a real-case filter. Indeed, the analytical filter considered in the design phase is an LCL filter, while the real case is an LLCL filter. This difference could impact the current harmonics rejected on the grid and breaks grid codes. The main objec...

Nowadays, the demand for flexible and wearable devices is significantly increasing. Thereby, sensors based on carbon materials are gaining importance due to their high flexibility, sensitivity and medical compatibility. Precisely, nanocomposite based pressure and strain sensors present an interesting potential of applied force detection that helps...

This study proposes an approach to synthesize a three-impulse sequence input shaper with a negative impulse, known as Unity Magnitude (UM) shaper. The corresponding analytic model has been already achieved for undamped and low-damped systems. In this paper, the analytic design of UM shaper is demonstrated for the generalized case of damped systems...

The problem of observer design naturally arises in a system approach as soon as one needs some internal information from external (directly available) measurements. In general, it is clear that one cannot use as many sensors as there are signals of interest characterizing the system behavior, for example, for cost reasons or technological constrain...

Recently, an adaptive control approach has been proposed. This approach, named L1 adaptive control, involves the insertion of a low-pass filter at the input of the Model Reference Adaptive Control (MRAC). This controller has been designed to overcome several limitations of classical adaptive controllers such as (i) the initialization of estimated p...