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Urb.n Air Quality Assessment of Kathmandu b. Passive Sampling Technique

Journal of Environmental Science and Engineering(A) 2012年第4期1卷 467-483页

作者： Rejina Maskey b.anju Mohan b.kram Gewali Krishna Manandhar bidya b. pradhan Pradeep Dangol Martin Ferm Central Department of Environmental Science Tribhuvan University Kathmandu 5003242 Nepal Central Department of Chemistry Tribhuvan University Kathmandu 5003242 Nepal International Centre for Integrated Mountain Development （ICIMOD） Kathmandu 5003242 Nepal IVL Swedish Environment Research Institute Goteborg SE-40014 Sweden

This paper presents an assessment of air quality of the Kathmandu valley, capital city of Nepal. This is the largest urb.nized area in the country of ab.ut 300 km2. In the last two decades an intensive development of demographic, traffic and industry growth in the region was ob.erved which was reflected on the air quality degradation. In order to evaluate the urb.n air quality in Kathmandu, a field monitoring network for particle deposition, nitrogen dioxide （NO2） and sulphur dioxide （SO2） b. passive sampling with high space resolution was implemented in co-operation with IVL-Sweden. The net work composed of 60 monitoring sites distrib.ted in a grid of 1 × 1 km2 covering all over the main city and some rural valley. Monitoring were carried out for two seasons, rainy and dry as two campaign monitoring. The diffusive samplers were prepared and analyzed in IVL, Sweden. Good agreements in particle deposition b.tween the two campaigns were ob.erved. The particle deposition to the surrogate surface varied b.tween 3 and 608 μg@cm2·monthl for the monitoring periods. The NOz concentrations on the other hand were quite similar in the two campaigns, and the SO2 concentrations were much lower in the first campaign compared to the second. The ranges of NO2 and SO2 concentrations were found to b. from 5.6 to 52.6 μg/m3 and 0.6 to 23.4 μg·m-3 respectively. Arc Info/Arc map GIS 9.2 software was used for production of maps of spatial distrib.tion of all the three parameters in the valley. Seasonal variation and traffic influence were also studied. Local meteorological effects in the distrib.tion of pollutants were clearly ob.erved and the NO2 concentrations were strictly related with traffic intensity.

关键词： Urb.n air quality particle deposition nitrogen dioxide sulphur dioxide passive sampling diffusive sampling.

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Studies of grand minima in sunspot cycles b. using a flux transport solar dynamo model

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Research in Astronomy and Astrophysics 2013年第11期13卷 1339-1357页

作者： bidya b.nay Karak Arnab.Rai Choudhuri Department of Physics Indian Institute of Science

We propose that grand minima in solar activity are caused b. simultane- ous fluctuations in the meridional circulation and the b.b.ock-Leighton mechanism for the poloidal field generation in the flux transport dynamo model. We present the following results：（a） fluctuations in the meridional circulation are more effective in producing grand minima; （b. b.th sudden and gradual initiations of grand minima are possib.e; （c） distrib.tions of durations and waiting times b.tween grand minima seem to b. exponential; （d） the coherence time of the meridional circulation has an effect on the numb.r and the average duration of grand minima, with a coherence time of ab.ut 30 yr b.ing consistent with ob.ervational data. We also study the occurrence of grand maxima and find that the distrib.tions of durations and waiting times b.tween grand maxima are also exponential, like the grand minima. Finally we address the question of whether the b.b.ock-Leighton mechanism can b. operative during grand minima when there are no sunspots. We show that an a-effect restricted to the upper portions of the convection zone can pull the dynamo out of the grand minima and can match various ob.ervational requirements if the amplitude of this a-effect is suitab.y fine-tuned.

关键词： magnetic fields -- (magnetohydrodynamics:) MHD -- Sun: magneticfields -- (Sun:) sunspots

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Sub.ritical dynamo and hysteresis in a b.b.ock-Leighton type kinematic dynamo model

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Research in Astronomy and Astrophysics 2021年第10期21卷 250-256页

作者： Vindya Vashishth bidya b.nay Karak Leonid Kitchatinov Department of Physics Indian Institute of Technology(BHU)Varanasi 221005India Institute of Solar-Terrestrial Physics Sb.RAS Lermontov Str.126A664033IrkutskRussia Pulkovo Astronomical Ob.ervatory Pulkovskoe Sh.65St.Petersberg196140Russia

In the Sun and Sun-like stars,it is b.lieved that cycles of the large-scale magnetic field are produced due to the existence of differential rotation and helicity in the plasma flows in their convection zones(CZs).Hence,it is expected that for each star,there is a critical dynamo numb.r for the operation of a large-scale *** a star slows down,it is expected that the large-scale dynamo ceases to operate ab.ve a critical rotation *** our study,we explore the possib.lity of the operation of the dynamo in the sub.ritical region using the b.b.ock–Leighton type kinematic dynamo *** some parameter regimes,we find that the dynamo shows hysteresis b.havior,i.e.,two dynamo solutions are possib.e depending on the initial parameters—decaying solution if starting with weak field and strong oscillatory solution(sub.ritical dynamo)when starting with a strong ***,under large fluctuations in the dynamo parameter,the sub.ritical dynamo mode is unstab.e in some parameter ***,our study supports the possib.e existence of sub.ritical dynamo in some stars which was previously demonstrated in a mean-field dynamo model with distrib.tedαand MHD turb.lent dynamo simulations.

关键词： magnetic field Sun:activity Sun:magnetic fields stars:rotation stars:dynamo stars

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Application of multi-criteria decision making methods for selection of micro-EDM process parameters

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Advances in Manufacturing 2014年第3期2卷 251-258页

作者： A.P.Tiwary b.b.pradhan b.b.attacharyya Department of Mechanical Engineering Sikkim Manipal Institute of TechnologyEast Sikkim.Majitar 737136.India Department of Production Engineering Jadavpur UniversityKolkata 700032India

Ti-6A1-4V super alloy is an important engi- neering material with good strength to weight ratio and a wide range of applications in a numb.r of engineering fields b.cause of its excellent physical and mechanical properties. This work determines optimum process parameters such as pulse on time, peak current, gap voltage and flushing pressure, which influence the micro-electro discharge machining （EDM） process during machining of Ti-6AI-4V using comb.ned methods of response surface methodology （RSM） and fuzzy-technique for order pref- erence b. similarity to ideal solution （TOPSIS）. Central composite design （CCD） is used in the experimental investigation. A decision making model is developed to identify the optimum process parameters in the micro- EDM process, which influences several machining criteri- ons such as material removal rate （MRR）, tool wear rate （TWR）, overcut （OC） and taper. Triangular fuzzy numb.rs are used to determine the weighting factor for each process criterion. Further a fuzzy-TOPSIS method is used to select the most desirab.e factor level comb.nations. The proposed technique can b. used to select optimal process parameters from various sets of comb.nations of process parameters in a micro-EDM process.

关键词： Micro-EDM - Ti-6A1-4V Fuzzy-techniquefor order preference b. similarity to ideal solution(TOPSIS) Micromachining

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b.anchi Type-Ⅲ String Cosmological Models with Time Dependent b.lk Viscosity

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Chinese Physics Letters 2007年第2期24卷 585-588页

作者： b.LI Raj pradhan Anirudh Department of Mathematics University of Rajasthan Jaipur-302 004 India Department'of Mathematics Hindu Post-Graduate College Zamania-232 331 Ghazipur India

b.anchi type-Ⅲ string cosmological models with b.lk viscous fluid for massive string are investigated. To ob.ain the determinate model of the universe, we assume that the coeffcient of b.lk viscosity ξ is inversely proportional to the expansion θ in the model and expansion θ in the model is proportional to the shear g. This leads to b.=lC^n, where l and n are constants. b.haviour of the model in the presence and ab.ence of b.lk viscosity is discussed. The physical implications of the models are also discussed in detail.

关键词： Cosmological Dependent

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Structural and Optical Properties of Graphene Oxide Prepared b. Modified Hummers’Method

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Computers, Materials & Continua 2016年第6期52卷 175-185页

作者： N.Selvakumar Uday pradhan S.b.Krupanidhi Harish C.b.rshilia Nanomaterials Research Lab Surface Engineering DivisionCSIR-National Aerospace LaboratoriesBangalore-560017India Materials Research Center Indian Institute of ScienceBangalore-560012India

Graphene oxide was synthesized from graphite flakes using modified Hummers’*** interlayer spacings of graphite,graphite oxide and graphene oxide were measured using X-ray diffraction *** C/O atomic ratios of graphite oxide and graphene oxide were calculated from XPS *** transformation of graphite to graphite oxide and finally to graphene oxide was clearly ob.erved from the micro-Raman spectroscopy data and was confirmed from the FESEM ***-VIS-NIR spectrophotometer was used to study the ab.orb.nce of graphene oxide and reduced graphene oxide ***,the chemically reduced graphene oxide was heat-treated in air to ob.ain chemically modified graphene.

关键词： Graphene oxide Graphite,modified Hummers’method thermal annealing optical properties

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Hab.tat heterogeneity influences avian feeding guild composition in urb.n landscapes:evidence from b.ub.neswar,India

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Ecological Processes 2021年第1期10卷 418-427页

作者： b.b.u Prasad Panda b.Anjan Kumar Prusty b.swajit Panda Ab.nti pradhan Sib. Prasad Parida Environmental Sciences Department of Chemistry and BBRCITERSiksha‘O’Anusandhan(Deemed to be University)BhubaneswarOdishaIndia Department of Natural Resources Management and Geoinformatics Khallikote UniversityBerhampurOdishaIndia Department of Stem Cell Facility All India Institute of Medical SciencesNew DelhiIndia Department of Zoology School of Applied SciencesCenturion University of Technology and ManagementBhubaneswarOdishaIndia.

b.ckground:Hab.tat heterogeneity clearly distinguished in terms of availab.lity of food and hab.tat resources and landscape features(natural or human-modified)play a crucial role in the avian species composition and population *** examine this,a study was carried out in b.ub.neswar,India,to understand the ecological niche distinction in b.rds b.sed on hab.tat *** sampling was conducted in 30 sampling sites covering six different hab.tat types in a predominantly urb.n landscape of b.ub.neswar for understanding the ecological niche in *** b.rds were classified into 11 types of foraging ***:The insectivorous guild had the highest b.rd species richness(181 species)and the omnivorous guild had the lowest(11 species).The piscivorous guild and wetland hab.tat had the strongest linkage,followed b. the insectivorous guild and agricultural *** frugivorous guild was significantly correlated with forest hab.tats(r=0.386,pb.tats(r=0.281,pb.n area hosted a higher numb.r of b.rd species in certain hab.tat types,viz.,agricultural lands(52%,115 species)and forest patches(50%,111 species).Conclusion:The present study highlights the importance of agricultural lands,forest patches,parks and gardens,and wetlands inside the cityscape for supporting *** is therefore suggested that such hab.tats should b. conserved inside an urb.n area to protect native ***,the city development plan must invariab.y include strategies for conserving the forest patches inside the urb.n *** must b. taken to restrain the degradation of agricultural lands and reduce their utilization for non-agricultural purposes,which will help in further reducing the b.rd population decline in the urb.n landscape.

关键词： b.rd species richness Community structure Feeding guild Hab.tat characteristics Urb.n area

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b.yesian inference and life testing plans for generalized exponential distrib.tion

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Science China Mathematics 2009年第6期52卷 1373-1388页

作者： KUNDU Deb.sis pradhan b.swab.ata Department of Mathematics and Statistics Indian Institute of Technology KanpurKanpur 208016India Statistical Quality Control & Operations Research Unit Indian Statistical Institute203 B.T.RoadKolkata700108India

Recently generalized exponential distrib.tion has received considerab.e attentions. In this paper, we deal with the b.yesian inference of the unknown parameters of the progressively censored generalized exponential distrib.tion. It is assumed that the scale and the shape parameters have independent gamma priors. The b.yes estimates of the unknown parameters cannot b. ob.ained in the closed form. Lindley’s approximation and importance sampling technique have b.en suggested to compute the approximate b.yes estimates. Markov Chain Monte Carlo method has b.en used to compute the approximate b.yes estimates and also to construct the highest posterior density credib.e intervals. We also provide different criteria to compare two different sampling schemes and hence to find the optimal sampling schemes. It is ob.erved that finding the optimum censoring procedure is a computationally expensive process. And we have recommended to use the sub.optimal censoring procedure, which can b. ob.ained very easily. Monte Carlo simulations are performed to compare the performances of the different methods and one data analysis has b.en performed for illustrative purposes.

关键词： shape parameter scale parameter Markov Chain Monte Carlo importance Sampling fisher information matrix 62F15 62F10 62F99

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Moisture dependent physical properties of Lagenaria siceraria seed

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International Journal of Agricultural and b.ological Engineering 2013年第4期6卷 111-120页

作者： Prashant Pandharinath Said Rama Chandra pradhan Department of Farm Engineering Institute of Agricultural SciencesBanaras Hindu UniversityVaranasiUttar Pradesh 221005India

The investigation was done to evaluate the effect of moisture content on some physical properties of Lagenaria siceraria *** study was conducted at five moisture levels including 8.84%,10.10%,11.89%,12.60%and 15.10%(w.b.).Results showed that the mean value of principal dimensions,average diameters,surface area and 1000 seed mass increased linearly b.t aspect ratio decreased with increase in moisture *** sphericity increased in the moisture range of 8.84%to 11.89%b.t decreased with further raise in the moisture up to 15.10%.Gravimetric properties like b.lk density increased with increase in moisture content however true density and porosity decreased linearly with increase in moisture *** of repose and terminal velocity increased linearly with moisture content of the *** coefficient of friction increased linearly with seed moisture content on five experimental surfaces(plywood,galvanized iron,glass and plastic).The information pertaining to moisture dependant physical properties of Lagenaria siceraria seeds may b.come an essential part in design of processing machines and its unit operations,design of dehulling,oil expression and other processing equipments.

关键词： Lagenaria siceraria physical properties angle of repose aspect ratio gravimetric properties sphericity

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Prediction of spatial soil loss impacted b. long-term land-use/land-cover change in a tropical watershed

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Geoscience Frontiers 2019年第2期10卷 389-403页

作者： J.H.Ab.ulkareem b.pradhan W.N.A.Sulaiman N.R.Jamil Department of Environmental Science Faculty of Environmental StudiesUniversiti Putra Malaysia (UPM) Department of Soil Science Institute for Agricultural Research/Faculty of AgricultureAhmadu Bello University Department of Civil Engineering Faculty of EngineeringGeospatial Information Science Research Center (GISRC)Universiti Putra Malaysia (UPM) Centre for Advanced Modeling and Geospatial Information Systems (CAMGIS) Faculty of Engineering and Information TechnologyUniversity of Technology Sydney Department of Energy and Mineral Resources Engineering Choongmu-gwanSejong University

The devastating effect of soil erosion is one of the major sources of land degradation that affects human lives in many ways which occur mainly due to deforestation, poor agricultural practices, overgrazing,wildfire and urb.nization. Soil erosion often leads to soil truncation, loss of fertility, slope instab.lity, *** causes irreversib.e effects on the poorly renewab.e soil resource. In view of this, a study was conducted in Kelantan River b.sin to predict soil loss as influenced b. long-term land use/land-cover(LULC) changes in the area. The study was conducted with the aim of predicting and assessing soil erosion as it is influenced b. long-term LULC changes. The 13,100 km^2 watershed was delineated into four sub.catchments Galas, Pergau, Leb.r and Nenggiri for precise result estimation and ease of execution. GIS-b.sed Universal Soil Loss Equation(USLE) model was used to predict soil loss in this study. The model inputs used for the temporal and spatial calculation of soil erosion include rainfall erosivity factor,topographic factor, land cover and management factor as well as erodib.lity factor. The results showed that 67.54% of soil loss is located under low erosion potential(reversib.e soil loss) or 0-1 t ha^(-1) yr^(-1) soil loss in Galas, 59.17% in Pergau, 53.32% in Leb.r and 56.76% in Nenggiri all under the 2013 LULC *** from the correlation of soil erosion rates with LULC changes indicated that cleared land in all the four catchments and under all LULC conditions(1984-2013) appears to b. the dominant with the highest erosion losses. Similarly, grassland and forest were also ob.erved to regulate erosion rates in the area. This is b.cause the vegetation cover provided b. these LULC types protects the soil from direct impact of rain drops which invariab.y reduce soil loss to the b.rest minimum. Overall, it was concluded that the results have shown the significance of LULC in the control of erosion. Maps generated from the study may b. usef

关键词： Soil erosion USLE Landuse/cover changes GIS Malaysia

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