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Structural,thermomagnetic,and dielectric properties of Mn0.5Zn0.5GdxFe2-xO4(x=0,0.025,0.050,0.075,and 0.1)

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Journal of Advanced Ceramics 2020年第2期9卷 243-254页

作者： Lakshita PHOR vinod kumar Hydrogen Lab Department of PhysicsDCR University of Science and TechnologyMurthal-131039HaryanaIndia

In this paper,effect of Gd^3+was investigated on structural,magnetic,and dielectric properties of Mn0.5Zn0.5GdxFe2–xO4(x=0,0.025,0.050,0.075,and 0.1)nanoparticles prepared by facile coprecipitation method.X-ray diffraction(XRD)studies confirmed the single cubic spinel phase for all the samples and showed that lattice parameter(aexp)was found to increase from 8.414 to 8.446Åwith the substitution of Gd3+ions due to their larger ionic radii than the replaced Fe3+*** and size of developed nanoparticles were studied using transmission electron microscopy(TEM)and found that particle size decreased from 31.06 to 21.12 nm for x=0–*** properties showed that maximum magnetization decreased from 39.21 to 23.59 emu/g,and Curie temperature decreased from 192 to 176℃with increase in x from 0 to 0.1 due to weakening of superexchange *** parameters like dielectric constant(e¢ande¢),dielectric loss(tanδ),AC conductivity(σac),and impedance(Z¢and Z¢)as a function of frequency and composition were analyzed and *** was found thate¢,e¢,σac,and tanδvalues decreased with Gd substitution,which has been explained based on Maxwell–Wagner theory and hopping mechanism of electrons between Fe3+and Fe2+ions at octahedral *** plots for all the developed compositions showed single semi-circular arc which indicate the dominant effect of grain boundaries.

关键词： spinel ferrite coprecipitation method structural property magnetism dielectric property

Sustainable Integrated Inventory Model for Substitutable Deteriorating Items Considering Both Transport and Industry Carbon Emissions

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Journal of Systems Science and Systems Engineering 2022年第3期31卷 267-287页

作者： Ranu Singh vinod kumar Mishra Department of Mathematics and Scientific Computing Madan Mohan Malaviya University of TechnologyGorakhpur-273010U.P.India

Sustainable integrated inventory management policy focuses on reducing the environmental impact of the manufacturing and transport *** study develops an integrated single-manufacturer single-buyer inventory model for substitutable deteriorating items considering transport and industry carbon *** article categorizes carbon emissions into two parts:direct and indirect *** also assume two mutually substitutable items,and substitution is considered on the buyer's *** one of the items is out of stock,the demand for that item can be partially satisfied by the stock of the other item;else,demand will be *** purpose of this study is to minimize the integrated cost of the supply chain with total carbon emissions produced by industry and transport sectors and to determine the optimal number of deliveries,order level and carbon emission quantity.A solution procedure is developed to find the optimal values of the *** experiments and sensitivity analyses are presented to demonstrate the proposed model.

关键词： Integrated inventory model sustainability deteriorating items substitutable items carbon emission

Optimal integration of DGs into radial distribution network in the presence of plug-in electric vehicles to minimize daily active power losses and to improve the voltage profile of the system using bioinspired optimization algorithms

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Protection and Control of Modern Power Systems 2020年第1期5卷 21-35页

作者： Satish kumar Injeti vinod kumar Thunuguntla Department of Electrical Engineering National Institute of Technology WarangalTelengana State 506004India

Purpose:The increase in plug-in electric vehicles(PEVs)is likely to see a noteworthy impact on the distribution system due to high electric power consumption during charging and uncertainty in charging *** address this problem,the present work mainly focuses on optimal integration of distributed generators(DG)into radial distribution systems in the presence of PEV loads with their charging behavior under daily load pattern including load models by considering the daily(24 h)power loss and voltage improvement of the system as objectives for better system ***/methodology/approach:To achieve the desired outcomes,an efficient weighted factor multi-objective function is *** Swarm Optimization(PSO)and Butterfly Optimization(BO)algorithms are selected and implemented to minimize the objectives of the system.A repetitive backward-forward sweep-based load flow has been introduced to calculate the daily power loss and bus voltages of the radial distribution *** simulations are carried out using MATLAB ***:The simulation outcomes reveal that the proposed approach definitely improved the system performance in all *** PSO and BO,BO is comparatively successful in achieving the desired ***/value:The main contribution of this paper is the formulation of the multi-objective function that can address daily active power loss and voltage deviation under 24-h load pattern including grouping of residential,industrial and commercial *** of repetitive backward-forward sweep-based load flow and the modeling of PEV load with two different charging scenarios.

关键词： Plug-in electric vehicles(PEVs) Distributed generators(DGs) Repetitive distribution power flow Particle swarm optimization algorithm(PSO) Butterfly optimization(BO) Daily active power loss

Lyra's cosmology of hybrid universe in Bianchi-V space-time

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Research in Astronomy and Astrophysics 2018年第6期18卷 27-34页

作者： Anil kumar Yadav vinod kumar Bhardwaj Department of Physics United College of Engineering and Research Department of Mathematics GLA University

In this paper we have searched for the existence of Lyra’s cosmology in a hybrid universe with minimal interaction between dark energy and normal matter using Bianchi-V space-time. To derive the exact solution, the average scale factor is taken as a =(t~nekt)1/m which describes the hybrid nature of the scale factor and generates a model of the transitioning universe from the early deceleration phase to the present acceleration phase. The quintessence model makes the matter content of the derived universe remarkably able to satisfy the null, dominant and strong energy condition. It has been found that the time varying displacement β(t) co-relates with the nature of cosmological constant Λ(t). We also discuss some physical and geometrical features of the universe.

关键词： cosmology: hybrid universe cosmology: dark energy cosmology: Bianchi-V spacetime

Optimal Simultaneous Allocation of Electric Vehicle Charging Stations and Capacitors in Radial Distribution Network Considering Reliability

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Journal of Modern Power Systems and Clean Energy 2024年第5期12卷 1584-1595页

作者： B.vinod kumar Aneesa Farhan M A the Department of Electrical and Electronic Engineering National Institute of Technology TiruchirappalliTamilnaduIndia

The popularity of electric vehicles(EVs)has sparked a greater awareness of carbon emissions and climate *** mobility expansion and EV adoption have led to an increased infrastructure for electric vehicle charging stations(EVCSs),impacting radial distribution networks(RDNs).To reduce the impact of voltage drop,the increased power loss(PL),lower system interruption costs,and proper allocation and positioning of the EVCSs and capacitors are *** paper focuses on the allocation of EVCS and capacitor installations in RDN by maximizing net present value(NPV),considering the reduction in energy losses and interruption *** a part of the analysis considering reliability,several compensation coefficients are used to evaluate failure rates and pinpoint those that will improve *** locate the best nodes for EVCSs and capacitors,the hybrid of grey wolf optimization(GWO)and particle swarm optimization(PSO)(HGWO_PSO)and the hybrid of PSO and Cuckoo search(CS)(HPSO_CS)algorithms are proposed,forming a combination of GWO,PSO,and CS *** impact of EVCSs on NPV is also investigated in this *** effectiveness of the proposed optimization algorithms is validated on an IEEE 33-bus RDN.

关键词： Electric vehicle charging station optimization radial distribution network vehicle-to-grid loss reduction reliability

Zn^(2+) substituted superparamagnetic MgFe_(2)O_(4) spinel-ferrites:Investigations on structural and spin-interactions

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Journal of Advanced Ceramics 2020年第5期9卷 576-587页

作者： Lakshita PHOR Surjeet CHAHAL vinod kumar Department of Physics Deenbandhu Chhotu Ram University of Science and TechnologyMurthal 131039HaryanaIndia

Nano-magnetic ferrites with composition Mg_(1-x)Zn_(x)Fe_(2)O_(4)(x=0.3,0.4,0.5,0.6,and 0.7)have been prepared by coprecipitation method.X-ray diffraction(XRD)studies showed that the lattice parameter was found to increase from 8.402 to 8.424A with Zn^(2+) ion content from 0.3 to *** transform infrared(FTIR)spectra revealed two prominent peaks corresponding to tetrahedral and octahedral at around 560 and 430 cm^(-1) respectively that confirmed the spinel phase of the *** electron microscopy(TEM)images showed that the particle size was noted to increase from 18 to 24 nm with an increase in Zn content from x=0.3 to *** magnetic properties were studied by vibrating sample magnetometer(VSM)and electron paramagnetic resonance(EPR)which ascertained the superparamagnetic behavior of the samples and contribution of superexchange *** maximum magnetization was found to vary from 23.80 to 32.78 emu/g that increased till x=0.5 and decreased ***,X-ray photoelectron spectroscopy(XPS)was employed to investigate the chemical composition and substantiate their oxidation states.

关键词： nanoparticles(NPs) nanospinel ferrites structural properties magnetism coprecipitation method

Optimization of Distributed Solar Photovoltaic Power Generation in Day-ahead Electricity Market Incorporating Irradiance Uncertainty

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Journal of Modern Power Systems and Clean Energy 2021年第3期9卷 545-560页

作者： Anu Singla Kanwardeep Singh vinod kumar Yadav the Department of Electrical Engineering Chitkara University Institute of Engineering and TechnologyChitkara UniversityPunjabIndia the Department of Electrical Engineering Guru Nanak Dev Engineering CollegeLudhianaIndia(affiliated to I.K.Gujral Punjab Technical UniversityKapurthalaIndia) the Department of Electrical Engineering Delhi Technological UniversityDelhiIndia

This paper proposes a simple and practical approach to model the uncertainty of solar irradiance and determines the optimized day-ahead(DA)schedule of electricity *** problem formulation incorporates the power output of distributed solar photovoltaic generator(DSPVG)and forecasted load demands with a specified level of *** proposed approach determines the certainty levels of the random variables(solar irradiance and forecasted load demand)from their probability density function *** this process of optimization,the energy storage system(ESS)has also been mod-eled based on the fact that the energy stored during low locational marginal price(LMP)periods and dispatched during high LMP periods would strengthen the economy of DA *** objective of the formulated non-linear optimization problem is to maximize the social welfare of market participants,which incorporates the assured generation outputs of DSPVG,subject to real and reactive power balance and transmission capability constraints of the system and charging/dis-charging and energy storage constraints of *** simulation has been performed on the Indian utility 62-bus *** results are presented with a large number of cases to demonstrate the effectiveness of the proposed approach for the efficient,economic and reliable operation of DA electricity markets.

关键词： Electricity market energy storage market dispatching renewable energy social welfare solar photovoltaic power generator

Transmission congestion management considering multiple and optimal capacity DGs

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Journal of Modern Power Systems and Clean Energy 2017年第5期5卷 713-724页

作者： Rajagopal PEESAPATI vinod kumar YADAV Niranjan kumar Department of Electrical Engineering National Institute of Technology JamshedpurJamshedpurJharkhand 831014India Department of Electrical Engineering Gautam Buddha UniversityNoida 201334India

Transmission congestion management became a grievous issue with the increase of competitiveness in the power systems. Competitiveness arises due to restructuring of the utilities along with the penetration of auxiliary services. The present study depicts a multi objective technique for achieving the optimal capacities of distributed generators(DG) such as solar, wind and biomass in order to relieve congestion in the transmission lines. Objectives like transmission congestion, real power loss, voltages and investment costs are considered to improve the technical and economical performances of the network. Multi objective particle swarm optimization algorithm is utilized to achieve the optimal sizes of unity power factor DG *** insisted methodology is practiced on IEEE-30 and IEEE-118 bus systems to check the practical *** results of the proposed approach are compared with the genetic algorithm for both single and multi-objective cases. Results revealed that the intimated method can aid independent system operator to remove the burden from lines in the contingency conditions in an optimal manner along with the improvement in voltages and a reduction in real power losses of the network.

关键词： Transmission congestion Optimal power flow Distributed generation Particle swarm optimization

Two-electron quantum ring in short pulses

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Chinese Physics B 2015年第2期24卷 46-52页

作者： Poonam Silotia Rakesh kumar Meena vinod Prasad Department of Physics and Astrophysics University of Delhi Department of Physics Swami Shraddhanand CollegeUniversity of Delhi

The response of a two-electron quantum ring system to the short laser pulses of different shapes in the presence of external static electric field is *** variation of transition probabilities of the two-electron quantum ring from ground state to excited states with a number of parameters is shown and *** energy levels and wavefunctions of the system in the presence of static electric field are found by solving the time-independent Schrodinger equation numerically by the finite difference *** shape of the pulse plays a dominant role on the dynamics.

关键词： quantum ring ultrashort pulses transition probability