Papers by Shailesh kumar singh
Hydrological modeling has become a widely accepted theoretical tool for water resources engineeri... more Hydrological modeling has become a widely accepted theoretical tool for water resources engineering and management. Rainfall-runoff models are used both for short and medium time management (for example flood forecasting) and long-time design purposes. However, the application of hydrological models is limited due to several reasons. One important limitation is imposed by the availability of data and parameter estimation. Discharges are only measured at a few selected river cross sections, leading to a small number of catchments for which the runoff calculated from the models might be verified. Further, the high spatial and temporal variability of the meteorological input (such as precipitation, temperature or wind) cannot fully be captured by the usually small number of meteorological stations. Radar measurement of precipitation can provide more detailed space time information on precipitation but unfortunately the reliability of the data is at present still low. Other influencing ...
Data- and model-driven determination of flow pathways in the Piako catchment, New Zealand
Journal of Hydro-environment Research, 2021
Abstract Quantifying flow pathways within a larger catchment can help improve diffuse pollution m... more Abstract Quantifying flow pathways within a larger catchment can help improve diffuse pollution management strategies across subcatchments. But, spatial quantification of flow pathway contributions to catchment stream flow is very limited, since it is challenging to physically separate water from different paths and very expensive to measure, especially for larger areas. To overcome this problem, a novel, combined data and modelling approach was employed to partition stream flow in the Piako catchment, New Zealand, which is a predominantly agricultural catchment with medium to high groundwater recharge potential. The approach comprised a digital filtering technique to separate baseflow from total stream flow, machine learning to predict a baseflow index (BFI) for all streams with Strahler 1st order and higher, and hydrological modelling to partition the flow into five flow components: surface runoff, interflow, tile drainage, shallow groundwater, and deep groundwater. The baseflow index scores corroborated the spatial distributions of the flow pathways modelled in 1st order catchments. Average depth to groundwater data matched well with BFI and Hydrological Predictions for the Environment (HYPE) modeled flow pathway partitioning results, with deeper water tables in areas of the catchment predicted to have greater baseflow or shallow and deep groundwater contributions to stream flow. Since direct quantification of flow pathways at catchment-scale is scarce, it is recommended to use soft data and expert knowledge to inform model parameterization and to constrain the model results. The approach developed here is applicable as a screening method in ungauged catchments.
International Journal of Modern Physics E, 2015
We analyze the effects of δ–meson on hypernuclei within the framework of relativistic mean field ... more We analyze the effects of δ–meson on hypernuclei within the framework of relativistic mean field theory. The δ–meson is included into the Lagrangian for hypernuclei. The extra nucleon–meson coupling (gδ) affects every piece of physical observables, like binding energy, radii and single-particle energies of hypernuclei. Magnitude of effects in hypernuclei is found to be relatively less than their normal nuclei because of the presence of Λ hyperon. Flipping of single-particle energy levels are observed with the strength of gδ in the considered hypernuclei as well as normal nuclei. The spin-orbit potentials are observed for considered hypernuclei and the effect of gδ on spin-orbit potentials is also analyzed. The calculated Λ binding energy (BΛ) are quite agreeable with experimental data. The sensitivity of BΛ for s- and p- orbitals with the strength of gδ is also analyzed. Lambda mean potential is investigated which is found to be consistent with other predictions.
International Journal of Engineering & Technology, 2018
An automotive industry sectors are facing major challenges to produce materials of high hardness,... more An automotive industry sectors are facing major challenges to produce materials of high hardness, low wear rate and corrosive resistant due to international intrinsic norms. Scientist and researchers are developing new materials with different surface properties to come over the international intrinsic norms and hence, they are trying to enhance tribological behavior and increase the life of automotive parts, make the parts corrosive resistant. Therefore, it has become essential to explore the new combinations of coating materials. A tribome-chanical effect of hard metal (WC-12 % Co and Cr3C2-25 % NiCr) coating on the cast iron and steel substrate were compared. Micro hardness, porosity, microstructure, corrosion and economical factor were compared and concluded that the hardness of WC-12%Co & Cr3C2-25NiCr coated on mild steel substrate were comparatively superior but the Cr3C2-NiCr coated cast iron substrate was better over WC-12%Co because it was more economical and corrosive resi...
Elephant Foot Yam (Amorphophallus) – An Efficient Intercrop under Indian Goose Berry (Phylanthus emblica) Orchard for Purvanchal
ABSTRACT
Tool for defining catchment similarity matrix
Central European Journal of Physics, 2014
The structures of Ne, Na, Mg, Al, Si, P and S nuclei near the neutron drip-line region are invest... more The structures of Ne, Na, Mg, Al, Si, P and S nuclei near the neutron drip-line region are investigated in the frame-work of relativistic mean field theory and non-relativistic Skyrme Hartree-Fock formalism. The recently discovered nuclei 40Mg and 42Al, which are beyond the drip-line predicted by various mass formulae are located within these models. We find many largely deformed neutron-rich nuclei, whose structures are analyzed. From the structure anatomy, we find that at large deformation low orbits of opposite parities (e.g. $$\frac{1} {2}^ +$$ and $$\frac{1} {2}^ -$$) occur close to each other in energy.
Hydrology, 2014
was done by two methods, using the depth function (identification of critical events (ICE) algori... more was done by two methods, using the depth function (identification of critical events (ICE) algorithm) and using random selection. Inter-comparison of the performance of the ANNs trained using the complete data sets and the pruned data sets shows that the ANN trained using the data from critical events, i.e., information-rich data (whose length could be one third to half of the series), gave similar results as the ANN trained using the complete data set. However, if the data set is pruned randomly, the performance of the ANN degrades significantly. The concept of this paper may be very useful for training data-driven models where the training time series is incomplete.
Central European Journal of Biology, 2014
An efficient protocol of plant regeneration through direct and indirect organogenesis in Swertia ... more An efficient protocol of plant regeneration through direct and indirect organogenesis in Swertia chirayita was developed. Explants cultured on Murashige and Skoog medium supplemented with 2,4-D (0.5 mg L−1) with combination of Kinetin (0.5 mg L−1) showed the highest frequency (84%) of callusing and 1.0mg L−1 6-benzyladenine (BA) in combination with (100 mg L−1) Adenine sulphate (Ads) + (0.1 mg L−1) Indole acetic acid (IAA) was excellent for maximum adventitious shoot (12.69 ± 1.30) formation in four week of culture. A maximum number of (7.14 ± 0.99) shoots were developed per leaf explants through direct organogenesis. The highest frequency of rooting (11.46 ± 1.56) was observed on MS medium augmented with IAA (1.0 mg L−1). Well-rooted shoots transferred to plastic pots containing a soilrite: sand mix and then moved to the greenhouse for further growth and development. Four major secondary metabolites were analyzed and quantified using high performance liquid chromatography. Amount o...
Pramana, 2014
A simple form for nucleon-nucleon (NN) potential is introduced as an alternative to the popular M... more A simple form for nucleon-nucleon (NN) potential is introduced as an alternative to the popular M3Y form using the relativistic mean field theory (RMFT) with the non-linear terms in σ-meson for the first time. In contrast to the M3Y form, the new interaction becomes exactly zero at a finite distance and the expressions are analogous with the M3Y terms. Further, its applicability is examined by the study of proton and cluster radioactivity by folding it with the RMFT-densities of the cluster and daughter nuclei to obtain the optical potential in the region of proton-rich nuclides just above the double magic core 100 Sn. The results obtained were found comparable with the widely used M3Y NN interactions.
Physical Review Letters, 1997
Physical Review D, 1997
We describe the properties of six-jet events, with six-jet mass exceeding 520 GeV/c 2 , produced ... more We describe the properties of six-jet events, with six-jet mass exceeding 520 GeV/c 2 , produced at the Fermilab proton-antiproton collider operating at a center-of-mass energy of 1.8 TeV. Observed distributions for a set of 20 multijet variables are compared with predictions from the HERWIG QCD parton shower Monte Carlo program, the NJETS leading order QCD matrix element Monte Carlo program, and a phase-space model in which six-jet events are distributed uniformly over the kinematically allowed region of the six-body phase space. In general the QCD predictions provide a good description of the observed six-jet distributions.
Switch failure in a two duplex unit standby system
Microelectronics Reliability, 1990
... UNIT STANDBY SYSTEM SK SINGH, RP SINGH Department of Mathematics and Statistics, Ravishankar ... more ... UNIT STANDBY SYSTEM SK SINGH, RP SINGH Department of Mathematics and Statistics, Ravishankar University, Raipur (MP), India and RB SINGH College ... REFERENCES 1. HR Singh, SK Singh and Sindhu Shukla, A two duplex unit standby system with two types of repair ...
Journal of Nanoscience and Nanotechnology, 2013
Aluminum catalyzed AlGaAs nanowires were fabricated on Si (111) substrates using metal-organic ch... more Aluminum catalyzed AlGaAs nanowires were fabricated on Si (111) substrates using metal-organic chemical vapor deposition (MOCVD) technique at a low growth temperature of 450 C. Grown structures were characterized by field emission scanning electron microscope (FE-SEM), energydispersive X-ray spectroscopy (EDS) and photoluminescence (PL) techniques. Nanowire clusters were observed all over the substrate. Multiprong root-grown AlGaAs nanowire clusters as well as catalyst particle terminated growth was observed. The growth is explained by Vapor-Solid-Solid (VSS) and Vapor-Solid (VS) growth mechanisms using Al-Si binary phase diagram. EDS and PL measurement confirm the formation of AlGaAs nanowires.
Profit evaluation of a two unit cold standby system with random change in units
International Journal of Systems Science, 1992
ABSTRACT
The permeability of hydraulic fills under surcharge
International Journal of Geotechnical Engineering, 2008
Mine stopes are large underground voids that are created in the process of removing the ore for t... more Mine stopes are large underground voids that are created in the process of removing the ore for the extraction of valuable minerals. The stopes can be approximated as rectangular prisms with plan dimensions in the order of 20-60 m and heights as much as 200 m. After ...
Hydrology Research, 2011
The parameters of hydrological models with no or short discharge records can only be estimated us... more The parameters of hydrological models with no or short discharge records can only be estimated using regional information. We can assume that catchments with similar characteristics show a similar hydrological behaviour. A regionalization of hydrological model parameters on the basis of catchment characteristics is therefore plausible. However, due to the non-uniqueness of the rainfall/runoff model parameters (equifinality), a procedure of a regional parameter estimation by model calibration and a subsequent fit of a regional function is not appropriate. In this paper, a different procedure based on the depth function and convex combinations of model parameters is introduced. Catchment characteristics to be used for regionalization can be identified by the same procedure. Regionalization is then performed using different approaches: multiple linear regression using the deepest parameter sets and convex combinations. The assessment of the quality of the regionalized models is also di...
Hydrological Sciences Journal, 2012
The use of a physically-based hydrological model for streamflow forecasting is limited by the com... more The use of a physically-based hydrological model for streamflow forecasting is limited by the complexity in the model structure and the data requirements for model calibration. The calibration of such models is a difficult task, and running a complex model for a single simulation can take up to several days, depending on the simulation period and model complexity. The information contained in a time series is not uniformly distributed. Therefore, if we can find the critical events that are important for identification of model parameters, we can facilitate the calibration process. The aim of this study is to test the applicability of the Identification of Critical Events (ICE) algorithm for physically-based models and to test whether ICE algorithm-based calibration depends on any optimization algorithm. The ICE algorithm, which uses the data depth function, was used herein to identify the critical events from a time series. Low depth in multivariate data is an unusual combination and this concept was used to identify the critical events on which the model was then calibrated. The concept is demonstrated by applying the physically-based hydrological model WaSiM-ETH on the Rems catchment, Germany. The model was calibrated on the whole available data, and on critical events selected by the ICE algorithm. In both calibration cases, three different optimization algorithms, shuffled complex evolution (SCE-UA), parameter estimation (PEST) and robust parameter estimation (ROPE), were used. It was found that, for all the optimization algorithms, calibration using only critical events gave very similar performance to that using the whole time series. Hence, the ICE algorithmbased calibration is suitable for physically-based models; it does not depend much on the kind of optimization algorithm. These findings may be useful for calibrating physically-based models on much fewer data.
Hydrological Processes, 2012
Lack of availability of historical data series is one of the major hindrances in hydrological mod... more Lack of availability of historical data series is one of the major hindrances in hydrological modelling. Regionalization of hydrological model parameters is one of the solutions to obtain the parameters for ungauged basins. Recently, lots of methodologies have been developed. They can be categorized as model calibration then fitting regression between model parameters and catchments characteristics, using some kind of transfer function. The aim of this study was to compare different regionalization methods as well as to look how the spatial resolution affects regionalization. In this study, a modified Lipschitz and monotony condition was used for regionalization. To identify the effect of the model resolution, the parameters of a distributed and semi-distributed version of the Hydrologiska Byråns Vattenbalansavdelning (HBV) model were regionalized. The study was conducted at the upper Neckar catchment of southwest Germany. It has been found that the combination of Lipschitz and monotony condition has performed reasonably. It has been seen that the distributed model structure has outperformed the semi-distributed model structure. It shows under present data conditions that higher model resolution can describe processes of ungauged basins reasonably.
Geotechnical and Geological Engineering, 2011
Hydraulic fills are one of the most common backfills used by mining industries to backfill the st... more Hydraulic fills are one of the most common backfills used by mining industries to backfill the stopes (voids) created after extracting the ore. It is important to estimate the stresses within to the stope to design the drainage and barricades. Most of the existing analytical models for the estimation of stresses within the stopes consider flat rectangular elements to include the effects of arching, although a continuous compression catenary arch of principal stresses using intersections of shear lines is the reality in field situations. In this paper, a circular compression arch of principal stresses has therefore been used to derive a general expression for stress within the inclined stopes. The results have been compared with the existing analytical and numerical models for vertical stopes as well as inclined stopes. A methodology has been presented to determine the vertical stress variation along the width of stope at different depths. The variation of stresses along the width of stope is also presented graphically.
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Papers by Shailesh kumar singh