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Analytical solution for fractional derivative gas-flow equation in porous media

In this paper, we introduce an analytical solution of the fractional derivative gas transport equation using the power-series technique. We present a new universal transform, namely, generalized Boltzmann change of variable which depends on the fractional order, time and space. This universal transform is employed to transfer the partial differential equation into an ordinary differential equation. Moreover, the convergence of the solution has been investigated and found that solutions are unconditionally converged. Results are introduced and discussed for the universal variable and other

Energy and Water
Circuit Theory and Applications

Fractional-Order Model (FOM) for high-strength substrate biodegradation in conventional UASB reactor

This paper introduces a Fractional-Order Model (FOM) of Up-flow Anaerobic Sludge Blanket (UASB) reactor for wastewater treatment regarding high-strength substrate biodegradation. The model can investigate the biogas production rate as well as the specific growth rate of bacteria with extra degree of freedom. Also, the hereditary effect of resident biomass on substrate degradation is studied on periodically long terms. Moreover, biomass concentration is examined in reactor under the influence of various fractional orders. Several numerical simulation results are introduced based on Grünwald

Energy and Water
Circuit Theory and Applications

Modified kinetic-hydraulic UASB reactor model for treatment of wastewater containing biodegradable organic substrates

This paper addresses a modified kinetic-hydraulic model for up-flow anaerobic sludge blanket (UASB) reactor aimed to treat wastewater of biodegradable organic substrates as acetic acid based on Van der Meer model incorporated with biological granules inclusion. This dynamic model illustrates the biomass kinetic reaction rate for both direct and indirect growth of microorganisms coupled with the amount of biogas produced by methanogenic bacteria in bed and blanket zones of reactor. Moreover, the pH value required for substrate degradation at the peak specific growth rate of bacteria is

Energy and Water
Circuit Theory and Applications

Novel 3D memory-centric NoC architecture for transaction-based SoC applications

Large and complex system-on-chip devices consisting of many processor cores, accelerators, DSP functions and many other processing and memory elements are becoming common in the semiconductor industry nowadays. To communicate, these processing and memory elements need to have a network-on-chip (NoC) that is scalable enough to support large number of elements and large bandwidth among other requirements. This paper evaluates the performance of the 2D memory-centric NoC architecture from throughput and latency perspective versus the Mesh topology. We also propose a memory-centric architecture

Energy and Water
Circuit Theory and Applications

Frequency-dependent effective capacitance of supercapacitors using electrospun cobalt-carbon composite nanofibers

Mixing carbon-based materials with pseudocapacitive material is a widely used strategy to prepare high-energy, high-power supercapacitors. However, phase separation is inevitable after extended charging/discharging which leads to the degradation of performance metrics of the device. Here, we prepare in a single step cobalt-incorporated carbon nanofibers (CNF) by electrospinning homogeneous solutions of polyacrylonitrile (PAN) with cobalt acetate at different nominal proportions (1:0 to 1:1), and investigate their stability and capacitive behavior in symmetric supercapacitors. The

Energy and Water
Circuit Theory and Applications

Highlighting a Common Confusion in the Computation of Capacitance of Electrochemical Energy Storage Devices

[No abstract available]

Energy and Water
Circuit Theory and Applications

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

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

Commercial supercapacitor parameter estimation from step voltage excitation

Supercapacitors are crucial elements in advanced industrial electronic systems particularly when supplied from renewable energy sources. Here, we derive expressions for the current, power, and stored energy in a supercapacitor excited with a step voltage signal. Although, it is not common practice to charge supercapacitors using a step voltage, these devices are sometimes used in switching-type applications where they are subject to this type of signal. We validate the derived mathematical expression of the current via experiments on four different commercial devices. By fitting the measured

Energy and Water
Circuit Theory and Applications

Capacitive behavior and stored energy in supercapacitors at power line frequencies

Supercapacitors are commonly viewed and mainly employed as dc electrical energy storage devices. Their behavior at far-from-dc is usually overlooked and not well explored for potential applications. In this work, we investigate analytically and experimentally the performance of supercapacitor at high frequencies, including the 50 Hz/60 Hz power line frequencies. The variation of effective capacitance, power and energy with frequency are analyzed using a fractional-order model consisting of a series resistance and a constant phase element for both pure sinusoidal and full-wave rectified voltage

Energy and Water
Circuit Theory and Applications