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Clean Energy 2022年第4期6卷 534-549页

作者： pranupa s A.T.sriram s.Nagaraja rao M s Ramaiah University of Applied sciences BangaloreIndia

In this paper,the performance of a permanent magnet synchronous generator(pMsG)-based wind energy conversion system(WECs)supplied to an uncontrolled rectifier-fed boost converter(BC)interfaced with a three-phase T-type three-level inverter(TlI)has been *** proposed WECs involves three converters,namely an uncontrolled rectifier that is used for conversion from AC to DC;a BC supplied by a pMsG-fed rectifier used to enhance the voltage gain;and a grid-connected three-phase T-type TlI is proposed to eliminate power-quality issues with synchronization of grid voltage and *** main goal of this research is to model and control the grid-connected T-type TlI using a d-q synchronous frame for wind energy for regulating the DC-link voltage and transferring the generated wind power from the BC to the ***,the perturb&observe(p&O)-based maximum power point(Mpp)approach is recommended to keep track of the Mpp for a BC that is supplied from a pMsG-based WECs under constant and variable wind *** proposed pMsG-based WECs interfaced with grid-connected T-type TlI using d-q control has been computationally modelled,simulated and validated with constant and variable speeds using MATlAB®and simulink®.It is confirmed that the p&O-based Mpp approach ensures maximum power for varying wind speeds,and the total harmonic distortion of the T-type TlI grid current value is 3.18%,which is within IEEE-519 ***,with grid synchronization,the power factor of the T-type TlI is maintained at unity to avoid power-quality issues.

关键词： boost converter grid synchronization perturb&observe T-type three-level inverter wind turbine

Fractional Optimal Golomb Ruler Based WDM Channel Allocation

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光学学报 2003年第S1期23卷 631-632页

作者： Vrizlynn l. l. Thing M. K. rao p. shum Nanyang Technological University School of Electrical & Electronic Engineering Block S2 S2-B3c-23 Nanyang Avenue Singapore 639798Nanyang Technological University School of Electrical & Electronic Engineering Block S2 S2-B3c-23 Nanyang Avenue Singapore 639798Nanyang Technological University School of Electrical & Electronic Engineering Block S2 S2-B3c-23 Nanyang Avenue Singapore 639798

A novel channel allocation method, based on optimal golomb ruler, that allows reduction of FWM effect while maintaining bandwidth efficiency, is presented. simulation is carried out to show performance improvement in ... 详细信息

关键词： WDM as In of be for FWM OGR

Distribution pattern and conservation of threatened medicinal and aromatic plants of Central Himalaya, India

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Journal of Forestry Research 2011年第3期22卷 403-408页

作者： l. s. Kandari K.s. rao R. K. Maikhuri G. Kharkwal K. Chauhan C.p. Kala Research Centre for plant Growth & Development School of Biological & Conservation Sciences Private Bag X01 Scottsville 3209 University of KwaZulu-Natal Pietermaritzburg South Africa Department of Botany University of Delhi Delhi-110007 India G.B. pant Institute of Himalayan Environment and Development Srinagar Garhwal 246174 Uttarakhand India Graduate school of Environmental Earth science Hokkaido University Sapporo 060-0810 Japan Indian Institute of Forest Management P.O. Box 357 Nehru Nagar Bhopal- 462003 M.P. India

A study was conducted to examine the distribution pattern of four rhizomatous medicinal and aromatic plant species （MAps） viz., Angelica glauca, pleurospermum angelicoides, Rheum emodi and Arne- bia benthamii in different forest stands in Central Himalaya. Results show that A. glauca and p. angelicoides had a higher （50%） frequency at Chipkoan, Garpak and phagati forest, R. emodi had a higher （60%） frequency at Rishikund, suki and Himtoli, and A. benthamii had a higher （70%） frequency at suki and Khambdhar The densities of A. glauca （0.6 plants·m -2 ） and p. angelicoides （0.5 plants·m -2 ） were higher at Chipkoan and Garpak sites than at other micro-sites, while densities of R. emodi （0.8 plants·m -2 ） and A. benthamii （1.0 plants·m -2 ） were higher at suki and Khambdhar sites. A. glauca had highest total basal covers （TBC）（1.2 cm 2 ·m -2 ） at Chipkoan, p. angelicoides had highest TBC （0.92 cm 2 ·m -2） at lati kharak site, A. benthamii had the highest TBC （6.48 cm 2 ·m -2 ） atKhambdhar, and R. emodi had highest TBC （4.53 cm 2 ·m -2 ） at Rishikund. For the four studied species, A. glauca showed a contagious distribution, p. angelicoides and R. emodi showed the random and A. benthamii showed the regular type of distribution.

关键词： alpine ecosystem Himalaya medicinal and aromatic plants traditional knowledge Uttarakhand

A Fitted Numerov Method for singularly perturbed parabolic partial Differential Equation with a small Negative shift Arising in Control Theory

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Numerical Mathematics(Theory,Methods and Applications) 2014年第1期7卷 23-40页

作者： R.Nageshwar rao p.pramod Chakravarthy Department of Mathematics Visvesvaraya National Institute of TechnologyNagpur440010India

In this paper,a fitted Numerov method is constructed for a class of singularly perturbed one-dimensional parabolic partial differential equations with a small negative shift in the temporal *** boundary value problems are associated with a furnace used to process a metal sheet in control ***,the study focuses on the effect of shift on the boundary layer behavior of the solution via finite difference *** the shift parameter is smaller than the perturbation parameter,the shifted term is expanded in Taylor series and an exponentially fitted tridiagonal finite difference scheme is *** proposed finite difference scheme is unconditionally *** the shift parameter is larger than the perturbation parameter,a special type of mesh is used for the temporal variable so that the shift lies on the nodal points and an exponentially fitted scheme is *** scheme is also unconditionally *** applicability of the proposed methods is demonstrated by means of two examples.

关键词： singular perturbations parabolic partial differential equation exponentially fitted method differential-difference equations

BINARY TIssUE ClAssIFICATION sTUDIEs ON REsECTED HUMAN BREAsT TIssUEs UsING OpTICAl COHERENCE TOMOGRApHY IMAGEs

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Journal of Innovative Optical Health sciences 2011年第1期4卷 59-66页

作者： M.BHATTACHARJEE p.C.AsHOK K.DIVAKAR rao s.K.MAJUMDER Y.VERMA p.K.GUpTA laser Biomedical Applications and Instrumentation Division Raja Ramanna Center for Advanced Technology Indore 452013 India the Variable Energy Cyclotron Centre Kolkata(India) the school of physics and Astronomy University of St.AndrewsSt.AndrewsScotland(UK)

We report the results of a comparative study of Fourier domain analysis(FDA)and texture analysis(TA)of optical coherence tomography(OCT)images of resected human breast tissues for binary classification between normalabnormal classes and benignmalignant *** the incorporation of Fisher linear discriminant analysis(FlDA)in TA for feature extraction,the TA-based algorithm provided improved diagnostic performance as compared to the FDAbased algorithm in discriminating OCT images corresponding to breast tissues with three different *** specificity and sensitivity values obtained for normalabnormal classification were both 100%,whereas they were 90% and 85%,respectively for benignmalignant classification.

关键词： Optical coherence tomography breast tissue texture analysis Fourier domain analysis classification

Effects of soil salinity and Alkalinity on Grain Quality of Tolerant,semi-Tolerant and sensitive Rice Genotypes

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Rice science 2013年第4期20卷 284-291页

作者： p.sUREKHA rao B.MIsHRA s.R.GUpTA Central soil salinity Research Institute Kurukshetra University

soil salinity and alkalinity adversely affects the productivity and grain quality of rice. The grain quality of 19 rice genotypes characterized as salt tolerant （T）, semi-tolerant （sT） and sensitive （s） was assessed in lysimeters containing saline and highly alkaline soils. Head rice recovery was reduced by salinity stress whereas it was not affected by alkalinity stress. The ratio of length to width （grain dimensions） was significantly reduced in the T genotype even at low electrical conductivity （EC, 4 ms/cm） and alkalinity （pH 9.5）, whereas in the sT genotype, it was significantly reduced at high salinity （EC 8 ms/cm）. There was no significant effect of any levels of salinity or alkalinity on grain dimensions in the s genotype. Amylose content was significantly reduced in T and sT groups even at low EC （4 ms/cm） and alkalinity （pH 9.5） and the effect in the s genotype was only at high salinity. starch content showed significant reduction at high salinity and alkalinity （EC 8 ms/cm and pH 9.8） in the T and sT genotypes and no significant effect was observed in the s genotype. The effect of both levels of salinity （EC 4 and 8 ms/cm） and high alkalinity （pH 9.8） on gel consistency was observed only in the s genotype. The tolerant genotypes IR36 under high salinity, and CsIR10 and CsR11 under alkali stress showed less reduction in amylose content. The T genotype BR4-10, and sT genotypes CsR30, CsR29 and CsR13 showed better gel consistency under saline and alkali stress. Amylose content was affected even at low salinity stress and thus important to be considered in breeding rice for salt tolerance. Overall, the grain quality of T and sT genotypes was less affected by saline and alkali stress compared to s ones.

关键词： alkalinity amylose content electrical conductivity gel consistency rice salinity starch content

Influence of ageing on oil degradation and gassing tendency under high-energy electrical discharge faults for mineral oil and synthetic ester

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High Voltage 2020年第6期5卷 731-738页

作者： l.loiselle U.Mohan rao I.Fofana Research Chair on the Aging of power Network Infrastructure(ViAHT) Universitédu QuébecàChicoutimiChicoutimiQCG7H 2B1Canada

In this work, mineral oil and synthetic esters were selected at different ageing factors (based on acidity values). Fresh and aged oils have been subjected to high-energy discharges (repeated 100 breakdowns) to simulate electric faults of highly vulnerable intensity. The intent of this work is to understand the influence of high-energy electric faults on oil degradation and gassing tendency at different ageing conditions. In this study, the influence of the high-energy discharges on degradation and gassing tendency at different ageing factors is reported for mineral oil and synthetic esters. Oil degradation is reported by adopting ultraviolet spectroscopy, turbidity and particle counter as per american society for testing and materials (AsTM) standard test methods. Gassing tendencies and fault gas analysis are understood by dissolved the gas analysis using Duval's triangle and Duval's pentagon methods for mineral and non-mineral oils. It is found that the influence of high-energy discharges on oil degradation is higher in mineral oils to that of the synthetic esters. The intensity of the gassing tendency is higher for ester fluids;however, as per the Duval methods, the faulty conditions are at lower levels as compared to mineral oils.

关键词： synthetic energy high

Field Measurements of Influence of sand Transport Rate on structure of Wind-sand Flow over Coastal Transverse Ridge

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Chinese Geographical science 2008年第3期18卷 255-261页

作者： DONG Yuxiang s l NAMIKAs p A HEsp MA Jun school of Geography and planning SUN Yat-Sen University Guangzhou 510275 China Department of Geography and 4nthropology Louisiana State University USA

The structure of wind-sand flow under different total sand transport rates was measured with field vertical anemometer and sand trap on the crest of typical coastal transverse ridge in Changli Gold Coast of Hebei province, which is one of the most typical coastal aeolian distribution regions in China and famous for the tall and typical coastal transverse ridges. The measurement results show that, on the conditions of approximate wind velocities and same surface materials and environments, some changes happen to the structure of wind-sand flow with the increase of total sand transport rate on the crest of coastal transverse ridge. First, the sand transport rates of layers at different heights in the wind-sand flow increase, with the maximum increase at the height layer of 4-8cm. second, the ratios of sand trans-port rates of layers at different heights to total sand transport rate decrease at the low height layer (0-4cm), but increase at the high height layer (4-60cm). Third, the distribution of the sand transport rate in the wind-sand flow can be expressed by an exponential function at the height layer of 0-40cm, but it changes from power function model to ex-ponential function model in the whole height layer (0-60cm) and changes into polynomial function model at the height layer of 40-60cm with the increase of total sand transport rate. Those changes have a close relationship with the limit of sand grain size of wind flow transporting and composition of sand grain size in the wind-sand flow.

关键词： sand transport rate coastal transverse ridge structure of wind-sand flow field measurement

Investigation of nonlinear effects in Doppler reflectometry using full-wave synthetic diagnostics

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plasma science and Technology 2020年第6期22卷 1-7页

作者： O l KRUTKIN A B AlTUKHOV A D GURCHENKO E Z GUsAKOV s HEURAUX M A IRZAK l A EsIpOV T p KIVINIEMI C lECHTE s lEERINK p NIsKAlA G ZADVITsKIY Ioffe Institute St PetersburgRussia Institut Jean lamour UMR 7198 CNRs Univ.de LorraineBP 50840F-54011 NancyFrance Aalto University FI-02150 EspooFinland Institute of Interfacial process Eng.and plasma Technology D-70569 StuttgartGermany

In this work,Doppler reflectometry(DR)and radial correlation DR(RCDR)nonlinear scattering effects are studied using full-wave modeling with a set of representative FT-2 tokamak turbulence as *** of the RCDR correlation function and widening of the DR poloidal wavenumber spectrum are *** effect on the dependence of the DR signal frequency shift on the probing wavenumber is found,namely,this dependence‘linearizing’in the nonlinear scattering *** effects are shown to be weaker for O-mode probing than for X-mode probing,while a faster transition to nonlinear regime is demonstrated for RCDR compared to DR in both probing scenarios.

关键词： reflectometry numerical modeling full-wave modeling

MUlTIplE-sCATTERING DETERMINATION TO THE lOCAl ADsORpTION GEOMETRY OF sO_2/pd(111)

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Acta Metallurgica sinica(English letters) 2002年第1期15卷 81-86页

作者： s. Cao J.C. Tang p. Zhu l. Wang s.l shen Dept. of phys. Zhejiang Univ. Hangzhou 310027 China

We have calculated the sulphur 1s near edge X-ray absorption fine structure (NEXAFs) spectra of sO2 adsorbed on pd (111) in terms of the Multiple-scattering Cluster (MsC) method. The origin of the resonances in the NEXAFs spectra has been revealed. By the MsC calculation and a (DV)-Xα study we have for the first time identified two weak features existing in s K-edge NEXAFs of sO2/pd(111) system, which are attributed to the interaction between the adsorbate and the substrate. Moreover, MsC calculation together with the reliability factor (R-factor) analysis are employed to determine the local adsorption structures. These results are broadly in agreement with those of Fourier-transform analysis of the surface extended X-ray absorption fine structure (sEXAFs).

关键词： Absorption Geometry palladium scattering sulfur dioxide X ray spectroscopy