This work proposes general formulas for designing two different topologies of fractional-order relaxation oscillators. One topology contains an Operational Amplifier and the other one relies on an Operational Trans-Resistance Amplifier. The design procedure hinges on the general fractional-order natural and step responses of RC, which is proved in this work depending on Mittag Leffler function. The proposed topologies can be controlled to generate symmetrical and non-symmetrical square wave signals. They also benefit from the employment of fractional-order capacitors (FOCs), which makes it

Cancellable biometrics is the art of generating distorted or encrypted templates of original biometric templates. The evolution of cancellable biometrics is attributed to the advanced hacking technologies that can capture the original stored biometrics from databases. One of the solutions for this problem is to store cancellable biometric templates in the database rather than the original ones. This paper presents a cancellable face recognition scheme that is based on face image encryption with Fractional-Order (FO) Lorenz chaotic system. The basic idea is to generate user-specific random keys

Day after day, users' expectations of tomorrow vehicles' features are increasing. Although the industry's prime goal is users' satisfaction, many unsolved problems are still present. Amongst the major challenges are the huge interconnections and dependability within the Electronic Control Unit (ECU) used inside vehicles. Five years ago, the number of ECUs within a vehicle was about 70 ECUs. This number has doubled nowadays, and it is expected to double again in the near future. This adds challenges to both of network management and network security. The purpose of this paper is to enhance the

This paper introduces two new versions for memristor-based center pulse-width modulator (PWM) circuits. The proposed circuits use only one comparator which reduces the circuit complexity and power dissipation compared to a former work. The first design is based on two memristors and two resistors while the second design is based on four memristors. Theoretical analysis is provided, and the numerical solution is handled on MATLAB. Simulation is carried out on Cadence software, and the results follow the theoretical analysis. The experiment is implemented using commercial off-the-shelf

Meta-heuristic optimization algorithms are the new gate in solving most of the complicated nonlinear systems. So, improving their robustness, reliability, and convergence speed is the main target to meet the requirements of various optimization problems. In the current work, three different fractional-order chaos maps (FC-maps), which have been introduced recently, are incorporated with the fundamental flower pollination algorithm to tune its parameters adaptively. These maps are fractional logistic map, fractional sine map, fractional tent map, and their integer-order versions. As a result

Last decade witnessed a growth on developing of IoT architecture models to cope with various challenges and domains requirements. This leads to rapid increasing the number of the connected devices, which means large amount of data are needed to be stored and processed. Form this context, Cloud Computing is emerged as a solution to enable centrally unlimited storage of data and programs with the ability to access anytime from anywhere. The integration between IoT and cloud brings the concept of Cloud of Things (CoT) to support different types of data and multiple services with data ubiquity

This paper proposes FPGA realization of an IP core for generic fractional-order derivative based on Grünwald-Letnikov approximation. This generic design is applied to achieve reconfigurable realization of fractional-order chaotic systems. The fractional-order real-time configuration boosts the suitability of this particular realization for different applications, including dynamic switching, synchronization, and encryption. The proposed design targets optimized utilization of the FPGA internal resources and efficient employment of the external peripherals: switches and I/O ports in the FPGA

This article presents performance evaluation and comparison between Voltage Oriented Control (VOC) methods for PWM-rectifiers, two levels and three levels, in order to demonstrate the great advantages of using a three-level Neutral Point Clamped (NPC). The control of the DC bus voltage is carried out using the PI controller. The effectiveness of this approach is illustrated by simulation results using MATLAB/Simulink. © Springer Nature Switzerland AG 2019.

Enhancing the performance of high luminescent and dielectrically capable cadmium sulfide nanowire (CdS NW) is of great importance, because of their promising ability in analyzing the dimensionality and size. The tuned physical characteristics of semiconductor CdS NWs allowed the manipulation of both electronic and optoelectronic devices at the nanoscale by dispersing a new bent core (BC) liquid crystal (LC) compound. This was derived from a 4-chlororesorcinol central core unit with two terephthalate based rod-like units carrying chiral (S)-3, 7-dimethyloctyloxy (namely ‘CPDB’) terminal chains

Novel chitosan-ZnO composites have been synthesized as luminescent taggants for cellulosic materials. The synthesized chitosan-ZnO nanospheres (CS-ZnO NS), chitosan-ZnO-oleic acid quantum dots (CS-ZnO-oleic QD) and chitosan-ZnO-oleic acid:Eu3+ doped nanorods (CS-ZnO-oleic:Eu3+ NR) were characterized by X-ray diffraction, photoluminescence spectroscopy, FTIR spectroscopy and transmission electron microscopy. The prepared luminescent CS-ZnO composites were used in printing paste and applied to different types of papers and textiles by using screen printing technique. The colorimetric values of