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Assessment of the role of slit as a safety valve in failure of levees

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International Journal of Sediment Research 2008年第4期23卷 361-375页

作者： C.S.P.OJHA V.P.singh d.d.AdRIAN department of Civil Engineering Indian Institute of TechnologyRoorkee Uttaranchal 247667 IndiaProf. Caroline and William N. Lehrer distinguished Chair in Water Engineering Professor of Civil & Environmental Engineering and Professor of Biological and Agricultural Engineering Texas A & M University2117 TAMU Dept. of Biological & Agric. Engineering 321 Scoates Hall College Station Texas 77843-2117 USA department of Civil and Environmental Engineering Louisiana State UniversityBaton Rouge LA 70803-6405 U. S. A.Rubicon Professor

The development of a narrow channel or slit due to piping just underneath the base of levees channel has been reported to be useful to withstand the increase in the head beyond critical head conditions. Also, the maximum slit length has been emphasized to be up to half of the base width. By developing a model of critical head considering slit, it is found that the critical head can increase with the development of slit length only under certain conditions. Analysis of piping failure data indicates that the critical head expressions considering slit length constitute a potentially useful model for critical head.

关键词： Failure of levee Piping Flood defense Water head seepage erosion

Petrographic characteristics coals, Mahanadi Gondwana and paleomires of Mand-Raigarh Basin, Chhattisgarh, India

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International Journal of Coal Science & Technology 2016年第2期3卷 165-183页

作者： A. S. Naik M. P. singh N. Volkmann P. K. singh d. Mohantya d. Kumar Banaras Hindu University Varanasi India T U Bergakademie Freiberg Germany CSIR-Central Institute of Mining and Fuel Researchdhanbad India

Mand-Raigarh coalfield is one of the largest coalfields in the Mahanadi basin. The Geological Survey of India carried out initial study primarily on exploration. However, detailed petrographic and geochemical characters of the coals have not been done so far. This investigation is an attempt for petrographic and geochemical appraisal of the coals. Moreover, effort is also made for possible interpretation on development of coal facies. The results drawn from 30 composite coal samples suggest coals are rich in vitrinite, with collotelinite as the dominant maceral while liptinite macerals register low concentration. dominant mineral assemblages found were clay minerals, pyrite was recorded as disseminated, framboidal and euhedral forms, carbonates recorded were mainly siderites. The vitrinite reflectance random （VRo） mean values range from 0.44 % to 0.56 %, and the rank of coal is suggested as high volatile ＇B＇ to ＇A＇ sub- bituminous in rank. The rock-eval pyrolysis reveal TOC content varying from 37 % to 68.83 %, while low hydrocarbon generating potential is evident from low $2 and Tmax values. The Hydrogen Index （HI） versus Oxygen Index （OI） plot reveal that the samples belong to Kerogen type--II-III with input dominantly from terrestrial source, some samples also fall in Kerogen type--II domain indicating lacustrine input. Vitrinite reflectance result indicate that the samples are immature and approaching oil window, which is in agreement with data of the Rock-Eval parameters. The gelification index （GI） and tissue preservation index （TPI） indicate that the coal developed in a telematic set up with high tree density. The ground water index （GWI） and vegetation index （VI） demonstrate that the peat developed as an ombrogenous bog.

关键词： Mand-Raigarh coalfield Organic petrology Geochemistry Source rock

Performance analysis of SiGe double-gate N-MOSFET

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Journal of Semiconductors 2017年第4期38卷 38-44页

作者： A.singh d.Kapoor R.Sharma department of Electronics and Communication Engineering Vaish College of EngineeringRohtak 124001India department of Electronics and Communication Engineering Northern India Engineering CollegeNew Delhi 110053India

The major purpose of this paper is to find an alternative configuration that not only minimizes the limitations of single-gate（SG） MOSFETs but also provides the better replacement for future *** this paper,the electrical characteristics of SiGe double-gate N-MOSFET are demonstrated and compared with electrical characteristics of Si double-gate ***,in this paper the electrical characteristics of Si doublegate N-MOSFET are demonstrated and compared with electrical characteristics of Si single-gate *** simulations are carried out for the device at different operational voltages using Cogenda Visual TCAd ***,we have designed its structure and studied both Id-Vg characteristics for different voltages namely 0.05,0.1,0.5,0.8,1 and 1.5 V and Id-Vd characteristics for different voltages namely 0.1,0.5,1 and 1.5 V at work functions 4.5,4.6 and 4.8 eV for this *** performance parameters investigated in this paper are threshold voltage,dIBL,subthreshold slope,GIdL,volume inversion and MMCR.

关键词： double gate MOSFET dIBL GIdL volume inversion SiGe Genius tool

Modelling of Indian Monsoon Rainfall Series by Univariate Box-Jenkins Type of Models

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Advances in Atmospheric Sciences 1993年第2期10卷 211-220页

作者： S.d.dahale S.V.singh Indian Institute of Tropical Meteorology Pune 411008 IndiaIndian Institute of Tropical Meteorology Pune 411008 India

The time domain approach, i.e. Autoregressive (AR) processes, of time series analysis is applied to the monsoon rainfall series of India and its two major regions, viz. North-West India and Central India. Since the original time series shows no modelable structure due to the presence of high interannual variability, a 3-point running filter is applied before exploring and fitting appropriate stochastic models. Out of several parsimonious models fitted, AR(3) is found to be most suitable. The usefulness of this fitted model is validted on an independent datum of 18 years and some skill has been noted. These models therefore can be used for low skill higher lead time forecasts of monsoon. Further the forecasts produced through such models can be combined with other forecasts to increase the skill of monsoon forecasts.

关键词： Modelling of Indian Monsoon Rainfall Series by Univariate Box-Jenkins Type of Models

Improved Clamped diode Based Z-Source Network for Three Phase Induction Motor

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Intelligent Automation & Soft Computing 2023年第4期36卷 683-702页

作者： d.Bensiker Raja singh R.Suja Mani Malar Anna University Chennai600025TamilnaduIndia dMI College of Engineering Chennai600123TamilnaduIndia

The 3Φinduction motor is a broadly used electric machine in industrial applications,which plays a vital role in industries because of having plenty of beneﬁcial impacts like low cost and easiness but the problems like decrease in motor speed due to load,high consumption of current and high ripple occurrence of ripples have reduced its *** ultimate objective of this study is to control change in motor speed due to load *** improved Trans Z Source Inverter(ΓZSI)with a clamping diode is employed to maintain constant input voltage,reduce ripples and voltage *** operate induction motor at rated speed,different controllers are *** conventional Proportional-Inte-gral(PI)controller suffers from high settling time and maximum peak *** overcome these limitations,Fractional Order Proportional Integral derivative(FOPId)controller optimized by Gray Wolf Optimization(GWO)technique is employed to provide better performance by eliminating maximum peak overshoot *** proposed speed controller provides good dynamic response and controls the induction motor more *** complete setup is implemented in MATLAB Simulation to verify the simulation *** proposed approach provides optimal performance with high torque and speed along with less steady state error.

关键词： Three phase induction motor voltage source inverter improvedΓZSI with clamping diode PI controller fractional order PId controller gray wolf optimizer

differential Sensitivity of Macrocarpa and Microcarpa Types of Chickpea （Cicer arietinum L.） to Water Stress： Association of Contrasting Stress Response with Oxidative Injury

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Journal of Integrative Plant Biology 2006年第11期48卷 1318-1329页

作者： Harsh Nayyar Smita singh Satwinder Kaur Sanjeev Kumar Hari d. Upadhyaya department of Botany Panjab University Chandigarh 160014 India department of Plant Biology University of New Hampshire Durham New Hampshire 03824 USA International Crop Research Institute for Semi-Arid Tropics Hyderabad India）

Chickpea （Cicer arietinum L.） Is particularly sensitive to water stress at Its reproductive phase and, under conditions of water stress, will abort flowers and pods, thus reducing yield potential. There are two types of chickpea：（i） Macrocarpa （＂Kabull＂）, which has large, rams head-shaped, light brown seeds; and （11） Microcarpa （＂desl＂）, which has small, angular and dark-brown seeds. Relatively speaking, ＂Kabull＂ has been reported to be more sensitive to water stress than ＂desl＂. The underlying mechanisms associated with contrasting sensitivity to water stress at the metabolic level are not well understood. We hypothesized that one of the reasons for contrasting water stress sensitivity In the two types of chickpea may be a variation in oxidative injury. In the present study, plants of both types were water stressed at the reproductive stage for 14 d. As a result of the stress, the ＂Kabull＂ type exhibited an 80% reduction in seed yield over control compared with a 64% reduction observed for the ＂desi＂ type. The decrease in leaf water potential （ψw） was faster In the ＂Kabull＂ compared with the ＂desl＂ type. At the end of the water stress period, ψw was reduced to -2.9 and -3.1 MPa In the ＂desi＂ and ＂Kabuli＂ types, respectively, without any significant difference between them. On the last day of stress, ＂Kabuli＂ experienced 20% more membrane injury than ＂desi＂. The chlorophyll content and photosynthetic rate were significantly greater in ＂desi＂ compared with ＂Kabuli＂. The malondialdehyde and H202 content were markedly higher at the end of the water stress In ＂Kabull＂ compared with ＂desl＂, Indicating greater oxidative stress In the former. Levels of anti-oxidants, such as ascorblc acid and glutathlone, were significantly higher In ＂desl＂ than ＂Kabull＂. Superoxide dismutase and catalase activity did not differ significantly between the two types of chickpea, whereas on the 10th day, the activities of ascorbate peroxidase, dehydroascorbate reductase, and glutathione redu

关键词： "desi" "Kabuli" anti-oxidants chickpea drought oxidative stress.

development of mix design method based on statistical analysis of different factors for geopolymer concrete

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Frontiers of Structural and Civil Engineering 2022年第10期16卷 1315-1335页

作者： Paramveer singh Kanish KAPOOR department of Civil Engineering Dr B R Ambedkar National Institute of TechnologyJalandhar 144011India

The present study proposes the mix design method of Fly Ash(FA)based geopolymer concrete using Response Surface Methodology(RSM).In this method,different factors,including binder content,alkali/binder ratio,NS/NH ratio(sodium silicate/sodium hydroxide),NH molarity,and water/solids ratio were considered for the mix design of geopolymer *** 2d contour plots were used to setup the mix design method to achieve the target compressive *** proposed mix design method of geopolymer concrete is divided into three categories based on curing regime,specifically one ambient curing(25°C)and two heat curing(60 and 90°C).The proposed mix design method of geopolymer concrete was validated through experimentation of M30,M50,and M70 concrete mixes at all curing *** observed experimental compressive strength results validate the mix design method by more than 90%of their target ***,the current study concluded that the required compressive strength can be achieved by varying any factor in the mix *** addition,the factor analysis revealed that the NS/NH ratio significantly affects the compressive strength of geopolymer concrete.

关键词： geopolymer concrete mix design fly ash response surface methodology compressive strength stress—strain

Multi-Objective Optimization of Fused deposition Modeling for Mechanical Properties of Biopolymer Parts Using the Grey-Taguchi Method

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Chinese Journal of Mechanical Engineering 2023年第1期36卷 51-64页

作者： Kapil Kumar Hari singh department of Mechanical Engineering National Institute of TechnologyKurukshetra136119India

The urgent need to develop customized functional products only possible by 3d printing had realized when faced with the unavailability of medical devices like surgical instruments during the coronavirus-19 disease and the ondemand necessity to perform surgery during space *** have recently been the most appropriate option for fabricating surgical instruments via 3d printing in terms of cheaper and faster *** all 3d printing techniques,fused deposition modelling(FdM)is a low-cost and more rapid printing *** article proposes the fabrication of surgical instruments,namely,forceps and hemostat using the fused deposition modeling(FdM)*** mechanical properties are the only indicator to judge the quality of the functional *** mechanical properties of FdM-processed parts depend on various process *** parameters are layer height,infill pattern,top/bottom pattern,number of top/bottom layers,infill density,flow,number of shells,printing temperature,build plate temperature,printing speed,and fan *** strength and modulus of elasticity are chosen as evaluation indexes to ascertain the mechanical properties of polylactic acid(PLA)parts printed by *** experiments have performed through Taguchi’s L27orthogonal array(OA).Variance analysis(ANOVA)ascertains the significance of the process parameters and their percent contributions to the evaluation ***,as a multiobjective optimization technique,grey relational analysis(GRA)obtains an optimal set of FdM process parameters to fabricate the best parts with comprehensive mechanical *** electron microscopy(SEM)examines the types of defects and strong bonding between *** proposed research ensures the successful fabrication of functional surgical tools with substantial ultimate tensile strength(42.6 MPa)and modulus of elasticity(3274 MPa).

关键词： Fused deposition modeling Mechanical properties Taguchi method ANOVA Grey relational analysis SEM

Characterization of Bi2/3Cu3Ti4O12 ceramics synthesized by semi-wet route

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Progress in Natural Science:Materials International 2016年第6期26卷 567-571页

作者： Pooja Gautam Ankur Khare Sunita Sharma N.B.singh K.d.Mandal department of Chemistry Indian Institute of Technology(BHU) department of Chemistry & Biochemistry University of Maryland

Bi2/3Cu3Ti4O12（BCTO） ceramic was synthesized by the semi-wet route using metal nitrate solutions and solid TiO2powder in a stoichiometric ratio. Fourier transform infrared（FTIR） study of BCTO precursor powder and calcined ceramic showed the presence of alcoholic functional groups and the stretching band of Ti-O and Cu-O respectively. X-ray diffraction（XRd）, scanning electron microscope（SEM） and energy dispersive x-ray spectroscopy（EdX） were employed to characterize the structure, surface morphology and purity of the sintered BCTO ceramic respectively. X-ray diffraction study confirmed the single phase formation of BCTO ceramic at1073 K. The average dimension of grains calculated by SEM and AFM was found to be in the range of 0.73 ±0.2 μm with clear grain boundaries. Magnetic property was investigated over a wide temperature range 2–300 K at a magnetic field of 7 tesla. The Curie temperature was calculated by zero field cooled(MZFC) and field cooled(MFC) magnetization at 100 Oe applied field which was found to be 125 K. The sintered BCTO ceramic shows high dielectric constant（ε'=2.9×10～4） at 323 K and 100 Hz.

关键词： Ceramic Synthesis Structural properties Magnetic properties