Fractional Differential Equations

The science and technology of ultracapacitors are reviewed for a number of electrode materials, including carbon, mixed metal oxides, and conducting polymers. More work has been done using microporous carbons than with the other materials and most of the commercially available devices use carbon electrodes and an organic electrolytes. The energy density of these devices is 3¯5 Wh/kg with a power density of 300¯500 W/kg for high efficiency (90¯95%) charge/discharges. Projections of future developments using carbon indicate that energy densities of 10 Wh/kg or higher are likely with power densities of 1¯2 kW/kg. A key problem in the fabrication of these advanced devices is the bonding of the thin electrodes to a current collector such the contact resistance is less than 0.1 cm2. Special attention is given in the paper to comparing the power density characteristics of ultracapacitors and batteries. The comparisons should be made at the same charge/discharge efficiency.

Ultracapacitors: Why, How, and Where is the Technology

http://ieeexplore.ieee.org/iel5/5610941/5624686/05624745.pdf

Power electronics

System Identification I

Consider the function defined for $\alpha _{1},\ \alpha _{2} \in \mathbb{R}$ (α 1 2 +α 2 2 ≠ 0) and $\beta _{1},\beta _{2} \in \mathbb{C}$ by the series 

$$\displaystyle{ E_{\alpha _{1},\beta _{1};\alpha _{2},\beta _{2}}(z) \equiv \sum _{k=0}^{\infty } \frac{z^{k}} {\varGamma (\alpha _{1}k +\beta _{1})\varGamma (\alpha _{2}k +\beta _{2})}\ \ (z \in \mathbb{C}). }$$

(6.1.1)

Such a function with positive α 1 > 0, α 2 > 0 and real $\beta _{1},\beta _{2} \in \mathbb{R}$ was introduced by Dzherbashian [Dzh60].

Multi-index Mittag-Leffler Functions

In this paper, mild steel–mild steel (MS-MS) joints fabricated through microwave hybrid heating (MHH) have been characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), electron probe micro analyser (EPMA), Vicker’s microhardness measurement and tensile strength. The XRD spectrum of the developed joints shows substitution type of solid solution form in the joint zone. The back scattered electron (BSE) images of the joint obtained by SEM show complete melting of powder particle and consequently diffusion bonding takes place between the substrate and the powder particle. The electron probe micro analysis shows diffusion of element across the joint. The Vicker’s micro hardness of the joints was measured to be 420 ± 30 Hv, which is higher than that of substrate hardness 230 ± 10 Hv. The tensile strength of the sample was measured by an universal testing machine and found to be 240 MPa which is about 50% of base material strength. The SEM micrographs of the fractured sample indicate mixed modes of failure during fracture of the joint; both ductile and brittle modes of failures occurred as indicated by dimple and cleavage of the brittle faces, respectively.

/pdf/metallurgical-and-mechanical-characterization-of-mild-steel-1tqzwdwd0v.pdf

Metallurgical and mechanical characterization of mild steel-mild steel joint formed by microwave hybrid heating process

Microstructure and mechanical properties of microwave welded Inconel 718/ austenitic stainless steel (SS-316L) were investigated in this work. Principles of microwave hybrid heating were effectivel...

On microstructure and strength properties of microwave welded Inconel 718/ stainless steel (SS-316L)

Multi-objective Active Control Policy Design for Commensurate and Incommensurate Fractional Order Chaotic Financial Systems

Sixteen Jatropha curcas genotypes collected from four states were grown in randomized block design and evaluated for 12 characters. The genotypes showed significant differences in most component traits and seed yield, excepting primary branches/plant, fruits/bunch and seeds/fruit. The genotypes Utkal nursery, Phule1, IST 1, Jodhpur1 and Chhatrapati had above average (>84.7 g) seed yield/plant. Phenotypic coefficient of variation (PCV) & genotypic coefficient of variation (GCV) estimates were high for seed yield/plant followed by flowering bunches/plant, fruits/plant and secondary branches/plant. Heritability was high (>80%) for plant height, fruits/plant and 100 seed weight. Genetic advance (GA) was high (>50%) for seed yield/plant, fruits/plant and flowering bunches/plant. Moderate to high heritability accompanied with high genetic advance for seed yield/plant, fruits/plant and flowering bunches/plant indicated additive gene action and selection for these characters would be effective. Fruits/plant, flowering branches and bunches/plant, collar diameter and secondary branches/plant had high positive correlation with seed yield/plant. Flowering bunches/plant and fruits/plant had high positive direct effect on yield and indirect positive effect via these two traits greatly influenced positive association of other traits with yield. Seeds/fruit and 100 seed weight had moderate positive direct effect on yield. The remaining seven component traits had very low direct effect on yield. The character association and path analysis study revealed that selection for flowering bunches/plant and fruits/plant would be highly effective in bringing out improvement in yield. Selection for seeds/fruit and 100 seed weight would result in some improvement in yield. Thus, the ideotype to achieve high yield in Jatropha should have more number of flowering bunches/plant and fruits per plant and moderate to high value for seeds/fruit and 100- seed weight.

Genetic variability, character association and path analysis in Jatropha curcas.

This paper deals with the speed control of a permanent-magnet brushless direct current (PMBLDC) motor. A fractional order PID (FOPID) controller is used in place of the conventional PID controller. The FOPID controller is a generalized form of the PID controller in which the order of integration and differentiation is any real number. It is shown that the proposed controller provides a powerful framework to control the PMBLDC motor. Parameters of the controller are found by using a novel dynamic particle swarm optimization (dPSO) method. The frequency domain pole-zero (p-z) interlacing method is used to approximate the fractional order operator. A three-phase inverter with four switches is used in place of the conventional six-switches inverter to suggest a cost-effective control scheme. The digital controller has been implemented using a field programmable gate array (FPGA). The control scheme is verified using the FPGA-in-the-loop (FIL) wizard of MATLAB/Simulink. Improvement in the overall performance of the system is observed using the proposed FOPID controller. The energy efficient nature of the FOPID controller is also demonstrated.

https://journals.tubitak.gov.tr/elektrik/issues/elk-17-25-5/elk-25-5-59-1612-277.pdf

Shantanu Das

Papers

Metallurgical and mechanical characterization of mild steel-mild steel joint formed by microwave hybrid heating process

On microstructure and strength properties of microwave welded Inconel 718/ stainless steel (SS-316L)

Multi-objective Active Control Policy Design for Commensurate and Incommensurate Fractional Order Chaotic Financial Systems

Genetic variability, character association and path analysis in Jatropha curcas.

Modeling and control of a permanent-magnet brushless DC motor drive using a fractional order proportional-integral-derivative controller