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Sadjaad Ozgoli - IEEE Xplore Author Profile

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Nowadays, there are millions of people with movement disabilities around the world. In recent decades, robotic devices like exoskeletons have been designed for helping such people. Designing an advanced control system for these devices became a challenge for engineers. Most of the exoskeletons and leg prostheses switch between different locomotion modes manually, and it causes some demanding and h...Show More
A principled approach to modeling sociocognitive networks is fundamental to understanding the network interrelations which in turn can be used in many applications such as human behavior analysis or team performance assessment. More specifically, in the opinion domain, learning the cognitive links and making a proper model for causal relationships between individuals is necessary for both analysis...Show More
Opinion dynamics modeling has long been interesting to scientists because of its applications in the marketing industry as well as elections. Agreement, e.g., on a special product, has an affective influence on its manufacturing process. However, most of the existing opinion dynamics models are linear time invariant. In this article, eight non-linear time variant models for opinion dynamics are pr...Show More
Assistive robots have been grown in recent years and joints’ moving pattern is one of the important issues in these robots. The predefined trajectory for the robot brings some stability difficulties for the users. This paper introduces a systematic way to produce an optimal gait for the controller of the lower extremity exoskeleton. This optimal gait producing strategy releases us from the exhaust...Show More
Walking and standing are the two fundamental problems in patients with spinal cord injury. Gait disorders in neurologically disabled people can be treated by various techniques available today. Exoskeleton robots and functional electrical stimulation (FES) are the two important solutions in this field. However, each of them has its own drawback. The patient using an exoskeleton doesn't participate...Show More
This paper presents a method to reduce the oscillations of potential field-based path planning approach in presence of obstacles and in narrow passages. The oscillation issue might impede path planning progress and cause problems in implementation. The proposed method uses Nesterov's accelerated gradient (NAG) which is a first order optimization method. Compared to other first order methods used i...Show More
Recently, significant attention has been dedicated to the models of opinion dynamics in which opinions are described by real numbers and agents update their opinions synchronously by averaging their neighbors' opinions. One notable example in this setting is DeGroot model which studies in a fixed network how consensus is formed when individual opinions are updated using the average of the neighbor...Show More
Identification of those genes which cause diseases can develop the process of diagnosis and the treatment of diseases. In this paper, a gene selection method based on genetic algorithm (GA) and support vector machines (SVM) is presented. At first, Fisher criteria is utilized in order to do filtration for those genes which are noisy and redundant in high dimensional microarray data. Then, GA/SVM mo...Show More
In time-delayed systems in which the time delay is unknown and unpredictable, to guarantee the stability of the system, a compensation method should be used. In this paper, this method is based on the concept of network disturbance and communication disturbance observer (CDOB), which does not need the time delay model. Therefore, it can be implemented in teleoperation systems that contain communic...Show More
In this paper it is shown that the widely used lognormal path loss signal propagation model may not be a good choice for every indoor environment. Instead, a non-monotonic signal propagation model for an indoor environment is presented. This model, combined with received signal strength values, relative distance and directional information can exhibit several applications. As an example, access po...Show More
A Wireless Network Control System (WNCS) with time delay and possibility of packet dropouts is considered. As we know packet dropouts and time delays are much more of concern in wireless data networks compared to wired networks. Because of this importance the sensitivity of the designed controller for the discussed WNCS is studied when various time delay profiles are present in the networked contr...Show More
In this paper, the delay-dependent filtering problem is investigated for a more realistic nonlinear genetic regulatory network (GRN) with time-varying delays, stochastic intrinsic noises and extrinsic noise, where the stochastic noises exist in both the state dynamics and measurement equations. The purpose of the addressed filtering problem is to estimate the true concentrations of gene products s...Show More
In this paper a new method is proposed in order to guarantee stability and improved position tracking and force reflection for a nonlinear teleoperation system. This method is based on Lyapunov stability theorem and It is applied by algorithmically constructing appropriate Lyapunov-Krasovskii function via using the sum of squares programming. In current paper slave robot has interaction with nonli...Show More
In this paper a new linear state feedback controller for artificial pancreas is proposed to regulate the blood glucose level in diabetic patients. Diabetes mellitus is a family of chronic metabolic diseases in which body's blood glucose regulatory system doesn't function properly. In this study, Bergman's minimal model has been used as a base model, to reformulate dynamics of insulin and glucose c...Show More
Current paper presents a recursive fast terminal sliding mode controller used to regulate blood glucose concentration. The fast terminal sliding mode controller makes the output to converge to the equilibrium point robustly and in finite time. In the controller of the system, the gain will be selected a priori based on the magnitude of uncertainty. The bound of uncertainties usually cannot be calc...Show More
Robust fault detection filter (RFDF) is mainly designed to detect faults in linear time-invariant (LTI) systems inherently exposed to external disturbances. H-index norm technique is one of the RFDF designing methods. The main idea of our study is to apply a continuous H-index method to a real boiler model which is made proper by adding an auxiliary direct channel. A high pass filter is augmented ...Show More
Gait Rehabilitation Robot is an important and useful machine collaboration robot, which can operate the limbs that affected by a stroke or disorder like paraplegic to improve their normal operation. The control algorithms that are applied to set up should have good flexibility and safety to guarantee the effectiveness and comfort of the physiotherapies. The impedance control algorithm is one of th...Show More
This paper deals with the problem of designing a robust proportional-integral controller for a Lorenz chaotic system. The design methodology is based on a so called density function and formulated as a convex optimization program and solved by using sum of squares techniques. The robustness is guaranteed by exploiting parametric uncertainty bounds in design formulations in a manner similar to S-Pr...Show More
This paper investigates a delay-dependent L2 - L∞ filter design method for genetic regulatory networks (GRNs). The purpose of the addressed problem is to design a linear filter that can estimate the true concentrations of gene products such as mRNAs and proteins. At first, a nonlinear delayed GRN model is considered under intrinsic and extrinsic noises simultaneously in order to reflect the inhere...Show More
Based on the algorithm and control strategies of automatic transmission in the Truck, electronic control unit (ECU) are designed. Furthermore, a design model is applied to optimize shift quality and also to reduce test time. The circuit diagram of electronic control unit (ECU) hardware composes of power supply module, signal input channels, signal output channels, data storage module, driver circu...Show More
This paper considers the robust stability of uncertain teleoperation systems. Sufficient stability conditions are derived in terms of LMI by representing the teleoperation scheme in retarded form of time-delay systems. By choosing Lyapunov-Krasovski functional, a delay-independent robust stability criterion is presented. We show that the teleoperation system is stable and has good performance unde...Show More
This paper presents a sufficient stability condition for internet-based tele-operation systems in terms of LMI. The tele-operation scheme is modeled in state-space as a time-delay system in retarded form and a delay-independent stability criterion is extracted. By choosing Lyapunov-Krasovski functional, we show that the internet-based tele-operation system is stable and has good performance under ...Show More
This paper presents two multivariable nonlinear stabilizers, designed for a single machine infinite bus (SMIB) modeled by a standard ninth-order model. Multivariable feedback linearization (MFBL) and multivariable sliding mode control (MSMC) are proposed to regulate the output voltage and track the reference rotor angle at post-fault conditions. It is the first time that The MSMC method is designe...Show More
In this paper, the problem of controlling chaotic uncertain brushless dc motor, exposed to external disturbances, is considered. Two different methods, feedback linearization and sliding mode control, are used to suppress chaos and regulate the system around one of its unstable equilibrium points. Although being able to do the job of regulating and also tracking very well, feedback linearization m...Show More
In this paper, the problem of controlling chaos in Arneodo chaotic system is considered for the first time. Three different methods, feedback linearization, backstepping design and sliding mode control, are used to suppress chaos and regulate the system around one of its unstable equilibrium points. Simulation results show that all these three methods are efficient. We may also make the system rob...Show More