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Maintaining constant voltage and constant frequency between distributed generation is the foremost need nowadays from different magnitude of two dynamic energy generation. Droop control method having minimum THD is used with the help of proper tuning of PI controller for achieving the constant voltage and frequency from different magnitude of generation. Through this approach, the prediction and control become easy for the economic load dispatch center for dispersed generation in case of normal, faulty and emergency situations. The bidirectional energy supply between solar PV and EV depend on solar insolation temperature and SOC of the EV battery decide the difference of voltages which ultimately decide the direction of power flow. Harmonic reduction done by suitable SPWM firing pulse given to switches of the inverters. Passive filter is used to reduce theharmonics. EV operating as source and load gives the with droop controller giving minimum THD and bidirectional supply of EV charging station and power grid gives novel configuration of the work. [ABSTRACT FROM AUTHOR]

This work aims at a thorough understanding of the structural and Magnetic properties of Ni2-xCoxMnSn (x=0,1) Heusler alloys synthesized by a solid-state processing route. Structural analysis was performed by employing techniques like X-ray Diffraction (XRD) and scanning electron microscopy (SEM) together with energy-dispersive X-ray spectroscopy (EDX) to show the formation of alloys of desired stoichiometry. The SQUID magnetometry result shows that the studied compositions are soft ferromagnetic. The saturation moment for x=0 (Ni2MnSn) is close to the 3µB, value predicted by the Slater-Pauling rule. However, the moment for x=1 (NiCoMnSn) is much below the anticipated value of 6μB. The Ni-Mn-Sn ternary alloy's curie point and saturation magnetization are raised by the addition of Co. [ABSTRACT FROM AUTHOR]

We study the effect of Argon gas deposition pressure (~ 3, 6 and 20 mTorr) on the IMT characteristics of VO2 films grown on Si (100) substrates by RF magnetron sputtering of V2O5 target at 100W RF-power and ~ 700 °C substrate temperature. HRXRD confirms the dominant growth of polycrystalline VO2 phase. All the film exhibits typical IMT with hysteresis width which characterize the VO2 phase. The IMT increases from ~341K to ~355K, hysteresis width also increases from ~12K to ~ 26K whereas phase transition amplitude decreases from ~ 23 to ~ 12, respectively as Ar gas pressure increase from ~3 to 20 mTorr. The activation energy (EA) calculated in metallic (Insulating) comes out to be ~32 meV (~ 172 meV), ~309 meV (~ 214 meV) and~238 meV (~ 246 meV) at 3, 6 and 20 mTorr Ar gas deposition pressure. Present study brings out that VO2 films can be grown by RF sputtering of V2O5 target in Argon ambient and Argon gas pressure plays a critical role for growth optimization. However, lower Ar gas pressure is more conducive for better IMT characteristics and activation energy. [ABSTRACT FROM AUTHOR]

We report the structure and electrical transport of SrRuO3 (SRO) and La0.35Pr0.25Ca0.4MnO3 (LPCMO) thin films and SRO/LPCMO bilayers grown on (001) oriented LaAlO3 (LAO) substrates. The thin films and heterostructures were deposited by RF magnetron sputtering of SRO and LPCMO targets in 25 mtorr Ar+O2 ambient at 850°C. The thickness of the SRO, LPCMO, and the bilayer is estimated to be ~3 nm, 40 nm, and 43 nm, respectively. The HRXRD 2θ-ω scans reveal that these films are (i) single crystalline, (ii) oriented along out-of-plane c-direction, and (iii) under slight compressive strain. The SRO film undergoes metal-semiconductor transition at TMS ~160 K. In contrast, the LPCMO undergoes a first-order hysteretic insulator-metal transition (IMT) at TIM ~154 K and 174 K during cooling and warming cycles. In the bilayer, the IMT of LPCMO is shifted to ~170 K and ~182 K during the cooling and warming cycle, with the insulating state concomitantly transformed into a semiconducting one. [ABSTRACT FROM AUTHOR]

The scheduling of power generating units is also recognized as Unit Commitment (UC); is an important and complex constrained mixed-integer nonlinear optimization problem. Traditionally UC was solved for thermal Units only, however, with the widespread adoption of Renewable energy sources like wind farms, UC is now being solved for hybrid generating units. This makes UC even more challenging due to the inherent uncertainty of the velocity of the wind. Evolutionary Algorithms (EAs) are used for solving UC as the traditional techniques employed for solving UC, like Dynamic Programming, suffer from the 'curse of dimensionality. However, EAs are unconstrained optimization techniques, and that is why they require special methods for handling constraints. Operator design and constraint handling in an EA is largely dependent on the problem representation. This paper proposes a novel adaptive quantum-inspired evolutionary algorithm with binary and real representation and a novel Repair heuristic for constraint handling in solving UC with thermal and wind farms. Initial testing has been performed on a well-known UC problem with ten thermal units and wind farm for twenty-four hours varying load model. The results achieved are competing as compared to other well-known techniques. [ABSTRACT FROM AUTHOR]

Bi-2223 superconductor reveals high conductivity at or below the critical temperature (Tc). We have aimed to see the effect of doping on the different characteristics of the superconducting material. Therefore, in this paper, we report the synthesis and structural characterization of iron-doped BSCCO superconductor with compositional formula Bi2Sr2Can-1(Cu1-xFex)nO10+δ, where n=3 and x=0.01. The stoichiometric interaction is confirmed between two compounds in the studied sample. The structural characterization of the sample is recorded by X-Ray diffraction technique at room temperature, which confirms orthorhombic structure. The Lattice constants and average crystallite size of the particles are determined also. [ABSTRACT FROM AUTHOR]

We synthesized a ceramic superconductor Bi2Sr2Can-1(Cu1-xFex)3O10+δ with (n = 3, x = 0.01) by usual method of oxides superconductor. In this paper, we report the characterization of the said sample by Fourier Transform Infrared Spectroscopic (FTIR) method. This method provides information about structural and compound bonding formation for the studied sample in powder form. The sharper peaks in the recorded spectra are reflecting with a functional group in the high-frequency stretching and low frequency bending modes. In this study, the interaction between Cu-O and Fe-O bond occupies octahedral and tetrahedral positions due to occupancy of cations and anions. The increasing amount of (Fe) is showing the transmittance (T%) behavior with different bonding vibration modes. [ABSTRACT FROM AUTHOR]

Pre- and post-scission α-particle multiplicities have been measured for the reaction 16O + 194Pt at 98.4 MeV forming compound nucleus 210Rn. The α-particle’s yield has been measured in coincidence with the fission fragments at various angles. The moving source analysis was performed to extract the alpha particle multiplicity which yielded the contribution of pre- and postscission components. The pre-scission α-particle multiplicity has been compared with JOANNE2 statistical model code predictions to extract fission time scale and which is observed to be around 55zs (1zs=10-21s). [ABSTRACT FROM AUTHOR]

The impact of oxygen and air annealing on the magnetic and magnetotransport properties of Pr1- xCaxMnO3 (x =0.42) polycrystalline films has been investigated. Our results clear show that oxygen deficiency favors ferromagnetism destroys the charge ordering and induces zero magnetic field insulator-metal transition in this compound. In contrast oxygen annealing restores the charge ordering and favors antiferromagnetic ordering and only magnetic field induced insulator-metal transitions are observed. [ABSTRACT FROM AUTHOR]

We investigate the role of oxygen in the electronic phase coexistence in polycrystalline Pr0.58Ca0.42MnO3 (PCMO) thin filmsspray pyrolysis on single crystal SrTiO3 (001) substrates. All films are single phase and have good crystallographic orientation. Our results demonstrate that the ground state of oxygen deficient PCMO is a phase separated cluster glass in which both charge ordered-antiferromagnetic insulating (COI-AF) and ferromagnetic metallic (FMM) clusters coexist. Oxygen annealing is observed to (i) favour the COI phase, (ii) reduce the FMM fraction and (iii) weaken the cluster glass state. [ABSTRACT FROM AUTHOR]

The effect of size mismatch induced quenched disorder on magnetotransport properties has been studied in polycrystalline Nd0.55-xSmxSr0.45MnO3 (x=0.00, 0.05, 0.15, 0.25, 0.35, and 0.45) thin films (thickness ∼300nm) prepared on LaAlO3 [LAO (001)] single crystal substrates by chemical spray pyrolysis. X-ray diffraction (XRD) data reveals that the films have oriented growth along out-of-plane (OP) direction. The OP lattice parameter decreases on substitution of Sm3+ ions for Nd3+. The insulator-metal/PM-FM transition temperatures (TIM/TC) for all the compositions decrease systematically and the transitions get sharpened as the variance σ2 that measures the quenched disorder due to size mismatch. The in-plane and out-of-plane low field magnetoresistance (LFMR) are enhanced appreciably with increasing quenched disorder (σ2). The variation in peak magnetoresistance (maximum MR around TIM) with σ2 shows drastic change above σ2 = 0.008469Å2(x = 0.25). The small polaron activation energy also increases appreciably. The observed effects have been explained in terms of the size disorder induced carrier localization. [ABSTRACT FROM AUTHOR]

In the present work Sm0.53Sr0.47MnO3 thin films were deposited on single crystal LAO (LaAlO3/(100)) substrates by DC magnetron sputtering. The θ-2 and ω-2θ scans show that these films are epitaxially grown and are under small compressive strain. The paramagnetic-ferromagnetic (insulator-metal) transition was found at TC∼126 K (at TIM∼128 K). The magnetic state at T

In the present paper, we have studied structure, magnetic and transport properties of polycrystalline Bi0.6-xNdxMnO3 (x=0.0, 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6) sample samples synthesized via solid state reaction route. The magnetic measurements reveal that the charge ordering temperature (TCO) decreases with increasing x. Further, the antiferromagnetic (AFM) ordering temperature (TN) increases sharply at both extremes and remains nearly constant for x=0.2 - 0.4. At T

In the present work we have studied the variation of LFMR as a function of the angle (θ) between the applied magnetic field and the plane of the film. DC magnetron sputtering was used for film preparation on LSAT single crystal substrates from Sm0.55Sr0.45MnO3 targets synthesized by the solid state reaction route. X-ray diffraction confirmed the epitaxial nature of these films. These films have simultaneous ferromagnetic and metal insulator transition at ∼91 K. These films exhibit enhanced low field colossal magnetoresistance ∼99% at 3.6 kOe at 80 K. Huge anisotropy is observed in the MR, which decreases from ∼80% to 6% as θ increases from 0 to 90°. The evolution of the resistance as a function of time and the magnetic field at a constant temperature (T≈77 K) has also been studied. [ABSTRACT FROM AUTHOR]