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Protection and Control of Modern Power Systems 2022年第1期7卷 64-81页

作者： Raghvendra tiwari Ravindra kumar Singh Niraj kumar Choudhary Electrical Engineering Department MNNITAllahabadPayagrajUPIndia

Fault current magnitude in a microgrid depends upon its mode of operation,namely,grid-connected mode or islanded mode.Depending on the type of fault in a given mode,separate protection schemes are generally employed.With the change in microgrid operating mode,the protection scheme needs to be modified which is uneconomical and time inefficient.In this paper,a novel optimal protection coordination scheme is proposed,one which enables a common optimal relay setting which is valid in both operating modes of the microgrid.In this con-text,a common optimal protection scheme is introduced for dual setting directional overcurrent relays(DOCRs)using a combination of various standard relay characteristics.Along with the two variables,i.e.,time multiplier setting(TMS)and plug setting(PS)for conventional directional overcurrent relay,dual setting DOCRs are augmented with a third variable of relay characteristics identifier(RCI),which is responsible for selecting optimal relay characteristics from the standard relay characteristics according to the IEC-60255 standard.The relay coordination problem is formulated as a mixed-integer nonlinear programming(MINLP)problem,and the settings of relays are optimally determined using the genetic algorithm(GA)and the grey wolf optimization(GWO)algorithm.To validate the superiority of the pro-posed protection scheme,the distribution parts of the IEEE-14 and IEEE-30 bus benchmark systems are considered.

关键词： Plug setting Time multiplier setting Protection coordination Overcurrent relay Coordination time interval

Tinospora cordifolia attenuates antipsychotic drug induced hyperprolactinemia in Wistar rats

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Asian pacific Journal of Reproduction 2019年第3期8卷 132-140页

作者： Prashant tiwari Sunil kumar Dubey Pratap kumar Sahu Department of Pharmacology School of Pharmaceutical SciencesSiksha O Anusandhan(Deemed to be University)BhubaneswarOdisha751029India Department of Pharmacy Birla Institute of Technology and SciencePilaniIndia

Objective: To evaluate the anti-hyperprolactinemic effect of methanolic extract of Tinospora cordifolia against antipsychotic/neuroleptic drug induced hyperprolactinemia. Methods: A total of 48 Wistar albino rats were chosen in the study. To induce hyperprolactinemia, haloperidol at 5 mg/kg/day was intraperitoneally administered for 16 continuous days and sulpiride at 20 mg/kg/day was administered intraperitoneally for 28 continuous days. Methanolic extract of Tinospora cordifolia at 200 mg/kg/day and 400 mg/kg/day were administered orally 30 min before administration of haloperidol and sulpiride for 16 and 28 days, respectively. Then, we had evaluated prolactin, dopamine and antioxidant status in the treatment group as compared to haloperidol and sulpiride. Results: There was a significant (P<0.05) increase in serum prolactin level and decrease in dopamine level in the haloperidol and sulpiride treated animals. However, methanolic extract of Tinospora cordifolia significantly (P<0.05) decreased serum prolactin level and increased brain dopamine level. Further, superoxide dismutase and catalase level were also decreased significantly in the haloperidol and sulpiride treated groups as compared to those of the control group and the antioxidant status was restored significantly on treatment with methanolic extract of Tinospora cordifolia. Furthermore, methanolic extract of Tinospora cordifolia also reduced total leukocyte count, and increased red blood cell count and hemoglobin concentration. In addition, the spleen did not show signs of infection or inflammation in the experiments. Conclusions: Methanolic extract of Tinospora cordifolia has a significant anti-hyperprolactinemic effect which may be attributed to neuroprotective and antioxidant effects of its signature constituents like stepharanine.

关键词： Antipsychotic Neuroleptic Dopamine Prolactin Superoxide dismutase Catalase

Citation classics in pediatrics: a bibliometric analysis

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World Journal of Pediatrics 2018年第6期14卷 607-614页

作者： Viswas Chhapola Soumya tiwari Bobbity Deepthi Sandeep kumar Kanwal Department of Pediatrics Kalawati Saran Children's Hospital&Lady Hardinge Medical CollegeBangla Sahib RoadNew Delhi 110001India

Background Citation analysis provides insights into the history and developmental trajectory of scientific fields. Our objec-tive was to perform an analysis of citation classics in the journals of pediatric specialty and to examine their characteristics. Methods Initially, all the journals listed under the category of pediatrics (n = 120) were identified using Journal Citation Reports. Web of science database was then searched (1950–2016) to select the top-100 cited articles in the above identified pediatric journals. The top-100 cited article were categorized according the study design, sub-specialty, country, institutional affiliation, and language. Results The top-100 articles were published in 18 different journals, with Pediatrics having the highest numbers (n = 40), followed by The Journal of Pediatrics (n = 17). The majority (n = 62) of classics were published after 1990. The most cited article had citation count of 3516 and the least cited had a citation count of 593. The USA (n = 71) was the most commonly represented country, and 60 institutions contributed to 100 articles. Fifteen authors contributed to more than one classic as first or second author. Observational study (n = 55) was the commonest study design across all decades, followed by reviews (n = 12), scale development studies (n = 11), and guidelines (n = 11). Among the pediatric sub-specialties, growth and development articles were highly cited (n = 24), followed by pediatric psychiatry and behavior (n = 21), endocrinology (n = 15), and neonatology (n = 12). Conclusions The top-100 cited articles in pediatrics identify the impactful authors, journals, institutes, and countries. Obser-vational study design was predominant—implying that inclusion among citation classics is not related to soundness of study design.

关键词： Bibliometrics Citation analysis Citation count Publishing/trends Scientometrics

Higher-Order (F,α,β,ρ,d,E)-Convexity in Fractional Programming

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Journal of Mathematical Research with Applications 2023年第3期43卷 303-312页

作者： Himanshu tiwari Seema MEENA Deepak kumar D.B.OJHA Department of Mathematics Faculty of Science University of Rajasthan

In this paper we define higher order (F,α,β,ρ,d,E)-convex function with respect to E-differentiable function K and obtain optimality conditions for nonlinear programming problem (NP) from the concept of higher order (F,α,β,ρ,d)-convexity. Here, we establish Mond-Weir and Wolfe duality for (NP) and utilize these duality in nonlinear fractional programming problem.

关键词： E-convexity higher order (F,α, β, ρ, d,E)-convexity optimality conditions duality fractional programming

Plasmonic enhancement of upconversion emission in Ag@NaYF4:Er^3+/Yb^3+phosphor

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Journal of Rare Earths 2018年第9期36卷 903-910页

作者： S.K.Maurya S.R tiwari A.kumar K.kumar Optical Materials and Bio-imaging Research Laboratory Department of Applied PhysicsIndian Institute of Technology(Indian School of Mines)Dhanhad-826004India

In this article upconversion luminescence of silver nanoparticles（AgNPs） coated NaYF4：Er3＋/Yb3＋phosphor nano-particles was investigated.The prepared samples were characterized through various techniques.The surface plasmon band is observed for prepared AgNPs by analyzing UV-vis measurements and is used to enhance the upconversion emission.From the upconversion measurement the emission bands are observed at 522,546,and 656 nm corresponding to the 2 H11/2→ 4115/2,4 S3/2→4 I15/2and 4 F9/2→4 I15/2 levels,respectively.The upconversion emission intensity of the above bands is found to enhance for sample containing 1 mmol AgNPs.Decay time of 4 S3/2 and 4F9/2 levels is found to decrease on coating of AgNPs and hence intensity enhancement is assumed due to the surface plasmon resonance（SPR） effect.

关键词： Upconversion phosphor Surface plasmon resonance Decay time analysis CIE diagram Rare earths

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Plants altering hormonal milieu: A review

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Asian pacific Journal of Reproduction 2017年第2期6卷 49-53页

作者： Prashant tiwari Pratap kumar Sahu Department of Pharmacology School of Pharmaceutical SciencesSiksha'O'Anusandhan UniversityBhubaneswar

The aim of the present review article is to investigate the herbs which can alter the levels of hormones like Follicle stimulating hormone, Prolactin, Growth hormone, Insulin, Thyroxine, Estrogen, Progesterone, Testosterone, and Relaxin etc. Hormones are chemical signal agents produced by different endocrine glands for regulating our biological functions. The glands like pituitary, thyroid, adrenal, ovaries in women and testes in men all secrete a number of hormones with different actions. However, when these hormones are perfectly balanced then people become healthy and fit. But several factors like pathophysiological as well as biochemical changes, disease conditions, changes in the atmosphere, changes in the body, diet changesetc. may result in imbalance of various hormones that produce undesirable symptoms and disorders. As medicinal plants have their importance since ancient time, people have been using it in various ways as a source of medicine for regulation of hormonal imbalance. Moreover, it is observed that certain herbs have a balancing effect on hormones and have great impact on well-being of the people. So, considering these facts we expect that the article provides an overview on medicinal plants with potential of altering hormone level.

关键词： Hormone Medicinal plant

A threshold voltage model of short-channel fully-depleted recessed-source/drain(Re-S/D) SOI MOSFETs with high-k dielectric

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Chinese Physics B 2015年第10期24卷 604-611页

作者： Gopi Krishna Saramekala Sarvesh Dubey Pramod kumar tiwari Department of Electronics and Communication Engineering National Institute of Technology Shri Ramswaroop Memorial University

In this paper, a surface potential based threshold voltage model of fully-depleted（FD） recessed-source/drain（Re-S/D）silicon-on-insulator（SOI） metal-oxide semiconductor field-effect transistor（MOSFET） is presented while considering the effects of high-k gate-dielectric material induced fringing-field. The two-dimensional（2D） Poisson＇s equation is solved in a channel region in order to obtain the surface potential under the assumption of the parabolic potential profile in the transverse direction of the channel with appropriate boundary conditions. The accuracy of the model is verified by comparing the model＇s results with the 2D simulation results from ATLAS over a wide range of channel lengths and other parameters,including the dielectric constant of gate-dielectric material.

关键词： recessed-source/drain （Re-S/D） high-k gate-material fringing field and SCEs

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Chemical composition and source apportionment of PM2.5 and PM2.5-10 in Trombay （Mumbai, India）, a coastal industrial area

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Particuology 2018年第2期16卷 143-153页

作者： Sandeep Police Sanjay kumar Sahu Mahesh tiwari Gauri Girish Pandit Environmental Monitoring and Assessment Section Bhabha Atomic Research Centre Mumbai 400085 India Homi Bhabha National Institute Anushakti Nagar Mumbai 400094 India

PM2.5 and PM2.5 lo concentrations, elemental constituents, and sources in a densely populated coastal industrial area （Trombay, Mumbai） were investigated in 2010 and 2011.The PM2.s and PM2.s lo concentra- tions were 13.50-71.60 and 22.40-127.78 p^g/m3, respectively. The daily PM25 concentrations exceeded the Indian Central Pollution Control Board limit （60 μg/m3） several days in winter. Of the elements analyzed, Si then Al had the highest concentrations in PM2.5- 10, but black carbon then Si had the highest concentrations in PM2.s. The element concentrations varied widely by season. Al, Ca, Fe, Si, and Ti con- centrations were highest in summer, Cl, Mg, and Na concentrations were highest in the monsoon season, and the other trace metal concentrations in both PM2.5 and PM2.5-10 were highest in winter. The PM2.5 and PM2.5-10 sources were apportioned by positive matrix factorization. PM2.5 and PM2.5-10 had six dominant sources, crustal material （8.7% and 25.3%, respectively）, sea salt spray （6.1% and 15.0%, respectively）, coal/biomass combustion （25.5% and 13.8%, respectively）, fuel oil combustion （19.0% and 11.2%, respectively）, road traffic （ 17.7% and 12.6%, respectively）, and the metal industry （ 10.6% and 7.0%, respectively）. Anthropogenic sources clearly contributed most to PM2.5 but natural sources contributed most to PM2.5-10.

关键词： Trombay PM2.5 PM2.5-10 Black carbon Metals Positive matrix factorization

Analytical model for subthreshold current and subthreshold swing of short-channel double-material-gate MOSFETs with strained-silicon channel on silicon–germanium substrates

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Journal of Semiconductors 2014年第10期35卷 30-36页

作者： Pramod kumar tiwari Gopi Krishna Saramekala Sarvesh Dubey Anand kumar Mukhopadhyay National Institute of Technology Rourkela Department of Electronics and Communication Engineering Faculty of Electronics and Communication SRM University

The present work gives some insight into the subthreshold behaviour of short-channel double-material- gate strained-silicon on silicon-germanium MOSFETs in terms of subthreshold swing and off-current. The formu- lation of subthreshold current and, thereupon, the subthreshold swing have been done by exploiting the expression of potential distribution in the channel region of the device. The dependence of the subthreshold characteristics on the device parameters, such as Ge mole fraction, gate length ratio, work function of control gate metal and gate length, has been tested in detail. The analytical models have been validated by the numerical simulation results that were obtained from the device simulation software ATLASTM by Silvaco Inc.

关键词： strained-Si channel Si1-xGex substrate dual-metal gate subthreshold current subthreshold swing

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Boosting the energy harvesting performance of cantilever structured magneto-mechano-electric generator by controlling magnetic flux intensity on magnet proof mass

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Journal of Materiomics 2023年第4期9卷 735-744页

作者： Deepak R.Patil Seungah Lee atul Thakre Ajeet kumar Hyunseok Song Dae-Yong Jeong Jungho Ryu School of Materials Science and Engineering Yeungnam UniversityGyeongsan38541South Korea Centre for Functional Materials Vellore Institute of TechnologyVellore632014TamilnaduIndia Department of Materials Science&Engineering Inha UniversityIncheon22212South Korea Institute of Materials Technology Yeungnam UniversityDaehak-roGyeongsan38541South Korea

A cantilever-structured magneto-mechano-electric(MME)generator comprising a magnetoelectric composite with a magnet proof mass is a potential candidate for powering autonomous wireless sensor networks.Recently,the concept of a magnetic flux concentrator(MFC)to enhance the output performance of the MME generator by focusing the ultralow-intensity magnetic field into the MME generator was introduced.However,the MFC-concentrated magnetic flux mostly focused on the end tip of the MME cantilever rather than at the magnet proof mass located on the cantilever beam.Considering that the torque generated by the magnet proof mass contributes more than half of the output power of an MME generator,optimizing the volume and position of the proof-mass with MFC is crucial for better performance.Furthermore,a smaller proof-mass is desirable for the long-term reliability of cantilevertype harvesters.Hence,we investigated the effect of the position and weight(volume)of the magnet proof mass with respect to the MFC on the output performance of the MME generator through finite element analysis and experiments.The MME generator with the lighter magnet proof mass at the optimized position generated a maximum power of 5.35 mW under a 10 Oe magnetic field,which was 210%of that of the MME configuration used in our previous study.Furthermore,the MME generator showed broadband characteristics around the practical frequency of 60 Hz,which could provide more freedom to design the harvester with high performance.

关键词： Magneto-mechano-electric Magnetic flux concentrator Magnet proof mass Broadband IoT sensor