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Two-dimensional front-tracking model for film evaporation

To understand the physical process involved in film evaporation, a new numerical model is created using coupled quadratic finite element formulation of the conservation equations. The heat transport equation is solved in the three different phases (solid, liquid and vapor) while the Navier-Stokes equation are solved in the two fluids. The gradient discontinuity at the liquid vapor interface provides local value of the evaporative flux density that is directly linked to the interface velocity jump through mass conservation principle and used as boundary condition for two fluid flow computations

Energy and Water
Circuit Theory and Applications
Mechanical Design

Interfacial modification of perovskite solar cell using zno electron injection layer with pdms as antireflective coating

Recently, perovskite solar cells (PSCs) exhibits tremendous power conversion efficiency and has shown enhanced figures of merit being secured regarding cell stability. In this paper, perovskite solar cell with Zno electron injection layer is presented. The humidity degradation of the perovskite active layer and the efficiency of the cell is observed under several conditions. Using ZnO as a planner electron injection layer (EIL) instead of TiO2, the efficiency of the device significantly improved, showing low-resistance shunting pathways. Also, polydimethylsiloxane (PDMS) has been used as a

Energy and Water
Circuit Theory and Applications

Temperature-aware adaptive task-mapping targeting uniform thermal distribution in MPSoC platforms

As on-chip integration increases, the thermal distribution becomes spatially non-uniform and varies based on the power dissipation. In this paper, we introduce a temperature-aware task-mapping algorithm to prevent hotspots and achieve a highly uniform thermal distribution using adaptive multi-threshold values. The algorithm monitors the temperature of the cores, swaps tasks when the temperature of the core is relatively higher than the average temperature of the chip. Cores are switched off if they exceed an absolute maximum temperature. Using this algorithm, reliability is enhanced by

Energy and Water
Circuit Theory and Applications

A universal floating fractional-order elements/memelements emulator

In this paper, a generalized floating emulator block is proposed using grounded elements. The proposed emulator is a universal emulator that is used to realize any floating elements such as fractional-order element (FOE) and fractional-order memelements (FOME). Different implementations for the introduced emulator are presented using different active blocks and generalized impedances. The fractional-order parameters add an extra degree of controllability on the hysteresis loop (HL) and the location of the pinched point, which will be investigated. Circuit simulations for the proposed circuits

Circuit Theory and Applications

Stability analysis of fractional-order Colpitts oscillators

The mathematical formulae of six topologies of fractional-order Colpitts oscillator are introduced in this paper. Half of these topologies are based on MOS transistor, and the other half is based on BJT transistor. The design procedure for all of these topologies is proposed and summarized for each one. Stability analysis is very crucial in oscillators’ design, as oscillators should have its poles on the imaginary axis to obtain a sustained oscillation. Hence, determining the factors that control the oscillator’s stability is very important. An intensive study of the stability of Colpitts

Circuit Theory and Applications

A new hyperchaotic temperature fluctuations model, its circuit simulation, FPGA implementation and an application to image encryption

In this paper, we propose a new hyperchaotic temperature fluctuations model and describe its modelling in detail. We study the characteristics of the new hyperchaotic temperature fluctuations model such as its phase portraits, rest points, symmetry, invariance, Lyapunov characteristic exponents, bifurcation analysis, etc. In fact, it is shown that the new temperature fluctuations model has a self-excited, two-scroll, hyperchaotic attractor with complex properties. The circuit simulation of the new temperature fluctuations model is carried out in MultiSim to verify the feasibility of the

Circuit Theory and Applications

Enhanced hardware implementation of a mixed-order nonlinear chaotic system and speech encryption application

This paper introduces a study for the effect of using different floating-point representations on the chaotic system's behaviour. Also, it offers a comparison between the attractors at three different orders, (integer, fractional, and mixed-order). This comparison shows the minimum number of bits needed for all parameters to simulate the chaotic attractor in each case. Numerical simulations using Matlab are presented for all discussed chaotic systems. This study opens the door to implement chaotic systems and different applications digitally with low hardware area. The FPGA hardware

Circuit Theory and Applications

Emulation circuits of fractional-order memelements with multiple pinched points and their applications

This paper proposes voltage- and current-controlled universal memelements emulators. They are employed to realize the floating and grounded fractional-order memelements. The proposed emulators are implemented using different active blocks such as the second-generation current conveyor (CCII), Differential input double output transconductance amplifier (DOTA + ), balanced output CCII, and Differential voltage current conveyor (DVCC) with analog voltage multiplier. One of the main characteristics of the memristive elements is hysteresis loop behaviour with one pinched point, and the higher-order

Circuit Theory and Applications

A New Control Scheme for Hybrid Chaos Synchronization

This paper presents a new hybrid chaos synchronization scheme, which assures the co-existence of the full-state hybrid function projective synchronization (FSHFPS) and the inverse full-state hybrid function projective synchronization (IFSHFPS) between wide classes of three-dimensional master systems and four-dimensional slave systems. In order to show the capability of co-existence approach, numerical example is reported, which illustrates the co-existence of FSHFPS and IFSHFPS between 3D chaotic system and 4D hyperchaotic system in different dimensions. © Springer Nature Switzerland AG 2019.

Circuit Theory and Applications

Private communications method based on chua's chaotic system

In this paper a simple private communications system is proposed based on Chua's chaotic system. The system mainly consists of two synchronized chaotic circuits, the system encodes values to a message function according to the state of synchronization between the two circuits. Numerical simulations were carried out to prove the validity of the system, and spice simulations were carried out on the proposed physical system. © 2019 IEEE.

Circuit Theory and Applications