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1

Predictive models for estimation of labyrinth weir aeration efficiency

Aradhana Aradhana, Singh B., Sihag P.

Journal of Achievements in Materials and Manufacturing Engineering

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2021

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Vol. 105, nr 1

18--32

EN

Purpose: The purpose of the study is to estimate the aeration efficiency (E20) of Labyrinth weir using artificial intelligent (AI)-based models. Design/methodology/approach: The aeration efficiency (E20) was collected by using the nine models of Labyrinth weir with different shapes and dimensions. A total of 180 observations were used out of which 126 used to train the AI-based models and the remaining used to test the model. This observation consists of input variables such as Fraud number (Fr), Reynolds number (Re), numbers of keys (N), the ratio of head to the width of the channel (H/W), the ratio of crest length to width of the channel (L/W), the ratio of drop height to width of the channel (D/W) and shape factor (SF) and E20 as the output variables. The AI-based models used were Fuzzy Logic, multi-linear regression (MLR), adaptive neuro fuzzy interface system (ANFIS), and artificial neural network (ANN). Findings: The main findings of this investigation are that ANN is the best AI-based model that can estimate the E20 accurately than MLR, ANFIS, and Fuzzy Logic. Sensitivity analysis depicts that drop height at labyrinth weir is the essential factors for the estimation of E20; further, parametric studies have also been performed. Research limitations/implications: The proposed AI-based models can be used in the estimation of E20 with different shapes of labyrinth weir but still it needs improvement for the different dimensions. Practical implications: The best AI-based model can be used to calculate the E20 with the different values of input variables. Originality/value: There are no such AI-based models such as ANN, ANFIS, and Fuzzy Logic, available in the literature which can estimate the values of E20 accurately.

2

On propagation of Rayleigh type surface wave in five different theories of thermoelasticity

Singh B., Verma S.

International Journal of Applied Mechanics and Engineering

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2019

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Vol. 24, no. 3

661--673

EN

The governing equations for a homogeneous and isotropic thermoelastic medium are formulated in the context of coupled thermoelasticity, Lord and Shulman theory of generalized thermoelasticity with one relaxation time, Green and Lindsay theory of generalized thermoelasticity with two relaxation times, Green and Nagdhi theory of thermoelasticity without energy dissipation and Chandrasekharaiah and Tzou theory of thermoelasticity. These governing equations are solved to obtain general surface wave solutions. The particular solutions in a halfspace are obtained with the help of appropriate radiation conditions. The two types of boundaries at athe surface of a half-space are considered namely, the stress free thermally insulated boundary and stress free isothermal boundary. The particular solutions obtained in a half-space satisfy the relevant boundary conditions at the free surface of the half-space and a frequency equation for the Rayleigh wave speed is obtained for both thermally insulated and isothermal cases. The non-dimensional Rayleigh wave speed is computed for aluminium metal to observe the effects of frequency, thermal relaxation time and different theories of thermoelasticity.

3

Reflection of plane waves from surface of a generalized thermo-viscoelastic porous solid half-space with impedance boundary conditions

Singh B.

Mechanics and Mechanical Engineering

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2018

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Vol. 22, nr 4

1483--1496

EN

A phenomenon of reflction of plane waves from a thermally insulated surface of a solid half-space is studied in context of Lord-Shulman theory of generalized thermo-viscoelasticity with voids. The governing equations of generalized thermo-viscoelastic medium with voids are specialized in x-z plane. The plane wave solution of these equations shows the existence of three coupled longitudinal waves and a shear vertical wave in a generalized thermo-viscoelastic medium with voids. For incident plane wave (longitudinal or shear), three coupled longitudinal waves and a shear vertical wave reflect back in the medium. The mechanical boundary conditions at free surface of solid half-space are considered as impedance boundary conditions, in which the shear force tractions are assumed to vary linearly with the tangential displacement components multiplied by the frequency. The impedance corresponds to the constant of proportionality. The appropriate potentials of incident and reflected waves in the half-space will satisfy the required impedance boundary conditions. A non-homogeneous system of four equations in the amplitude ratios of reflected waves is obtained. These amplitude ratios are functions of material parameters, impedance parameter, angle of incidence, thermal relaxation and speeds of plane waves. Using relevant material parameters for medium, the amplitude ratios are computed numerically and plotted against certain ranges of impedance parameter and the angle of incidence.

4

Reflection of Plane Waves from Surface of a Generalized Thermo-viscoelastic Porous Solid Half-space with Impedance Boundary Conditions

Singh B.

Computational Methods in Science and Technology

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2018

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Vol. 24, No. 4

273--283

EN

A phenomenon of reflection of plane waves from a thermally insulated surface of a solid half-space is studied in the context of Lord-Shulman theory of generalized thermo-viscoelasticity with voids. The governing equations of generalized thermo-viscoelastic medium with voids are specialized in x-z plane. The plane wave solution of these equations shows the existence of three coupled longitudinal waves and a shear vertical wave in a generalized thermo-viscoelastic medium with voids. For incident plane wave (longitudinal or shear), three coupled longitudinal waves and a shear vertical wave reflect back in the medium. The mechanical boundary conditions on the free surface of solid half-space are considered as impedance boundary conditions, in which the shear force tractions are assumed to vary linearly with the tangential displacement components multiplied by the frequency. The impedance corresponds to the constant of proportionality. The appropriate potentials of incident and reflected waves in the half-space will satisfy the required impedance boundary conditions. A non-homogeneous system of four equations in the amplitude ratios of reflected waves is obtained. These amplitude ratios are functions of material parameters, impedance parameter, angle of incidence, thermal relaxation and speeds of plane waves. Using relevant material parameters for medium, the amplitude ratios are computed numerically and plotted against certain ranges of the impedance parameter and the angle of incidence.

5

Propagation of Rayleigh wave in two-temperature dual-phase-lag thermoelasticity

Singh B., Kumari S., Singh J.

Mechanics and Mechanical Engineering

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2017

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Vol. 21, nr 1

105--116

EN

The governing equations of transversely isotropic dual-phase-lag two-temperature thermoelasticity are solved for the surface wave solutions. The particular solutions in the half-space satisfy the boundary conditions at a thermally insulated /isothermal stress-free surface of a half-space to obtain the frequency equation of the Rayleigh wave for the cases of coupled thermoelasticity, Lord and Shulman thermoelasticity and dual-phase-lag thermoelasticity. Some particular and special cases are obtained. The numerical values of the non-dimensional speed of the Rayleigh wave are computed and shown graphically against frequency, non-dimensional elastic constant and two-temperature parameter. The effects of frequency, two-temperature and dual-phase-lag are observed on the nondimensional speed of Rayleigh wave.

6

An Improved Greedy Forwarding Scheme in MANETs

Mishra P., Gandhi C., Singh B.

Journal of Telecommunications and Information Technology

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2017

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nr 1

50--55

EN

Position-based routing protocols are widely accepted efficient solution for routing in MANETs. The main feature of position-based routing protocols is to use greedy forwarding methods to route data. The greedy forwarding methods select a node, either having maximum progress towards destination (distance-based principle) or minimum deviation with line between source and destination (direction-based strategy). The first method minimizes the hopcount in a path and on the other hand, second method minimizes the spatial distance between source and destination. The distance-based routing has a great impact on the selection of reliable node and the direction based routing plays a major role to increase the stability of route towards destination. Therefore, in this paper authors propose a weighted forwarding method, which combines both the selection, schemes to select an optimal next forwarding node in a range. The simulation results show that the proposed scheme performs better than existing position-based routing protocols.

7

Thermo-Mechanical Deformation and Stress Analysis of Hydroxyapatite/Titanium FGM plate by FEM

Sharma R., Jadon V. K., Singh B.

Mechanics and Mechanical Engineering

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2016

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Vol. 20, nr 4

499--513

EN

Hydroxyapatite(HA)/titanium(Ti) functionally graded materials(FGM) are latest materials used for medical implants, structural components in defense, in dentistry, in aviation, and other fields under various type of loads. A finite element analysis model is designed to study the behavior of a HA/Ti FGM plate under thermo-mechanical loadings. Simply supported plate subjected to mechanical and thermal loads on its top and bottom surface is considered with suitable temperature and loading function. The first-order shear deformation plate (FSDT) method is used to investigate the thermo mechanical behavior of functionally graded plate .The volume fraction of the FGM plate is varied smoothly and continuously along the thickness of the plate. Results are discussed for the deformation and stresses of HA/Ti FGM plate It is observed from the study that FGMs are able to resist higher temperatures and loads without delamination.

8

Link Quality and Energy Aware Geographical Routing in MANETs using Fuzzy Logics

Mishra P., Gandhi C., Singh B.

Journal of Telecommunications and Information Technology

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2016

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nr 3

5--17

EN

In literature, varieties of topology and geographical routing protocols have been proposed for routing in the MANETs. It is widely accepted that the geographical routings are a superior decision than topological routings. Majority of geographical routing protocols assume an ideal network model and choose the route that contains minimum number of hops. However, in reality, nodes have limited battery power and wireless links are additionally unreliable, so they may highly affect the routing procedure. Thus, for reliable data transmission, condition of the network such as link quality and residual energy must be considered. This paper aims to propose a novel multi-metric geographical routing protocol that considers both links-quality and energy metric along with progress metric to choose the next optimal node. The progress is determined by utilizing greedy as well as compass routing rather than pure greedy routing schemes. To combine these metrics, fuzzy logics are used to get the optimal result. Further, the protocol deals with “hole” problem and proposes a technique to overcome it. Simulations show that the proposed scheme performs better in terms of the packet delivery ratio, throughput and residual energy than other existing protocols.

9

Propagation of plane waves in a rotating transversely isotropic two temperature generalized thermoelastic solid half-space with voids

Bijarnia R., Singh B.

International Journal of Applied Mechanics and Engineering

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2016

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Vol. 21, no. 2

285--301

EN

The paper is concerned with the propagation of plane waves in a transversely isotropic two temperature generalized thermoelastic solid half-space with voids and rotation. The governing equations are modified in the context of Lord and Shulman theory of generalized thermoelasticity and solved to show the existence of four plane waves in the x – z plane. Reflection of these plane waves from thermally insulated stress free surface is also studied to obtain a system of four non-homogeneous equations. For numerical computations of speed and reflection coefficients, a particular material is modelled as transversely isotropic generalized thermoelastic solid half-space. The speeds of plane waves are computed against the angle of propagation to observe the effects of two temperature and rotation. Reflection coefficients of various reflected waves are also computed against the angle of incidence to observe the effects of various parameters.

10

Effect of flux composition on the percentage elongation and tensile strength of welds in submerged arc welding

Singh B., Khan Z. A., Siddiquee A. N., Maheswari S., Sharma S. K.

Archive of Mechanical Engineering

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2016

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Vol. LXIII, nr 3

337--354

EN

This experimental study reveals the effects of CaF2, FeMn and NiO additions to the base fluxes on tensile strength and percentage elongation of the weld metal. The aim of this study is to develop suitable flux for mild steel for high tensile strength, impact strength and ductility. Bead on plate welds were made using submerged arc welding process. Mathematical model for percentage elongation and UTS of mild steel welds were made. The elements transfer to the welds have been correlated with the above mechanical performance characteristics. The effect of oxygen content on weld elongation and UTS also has been deduced. This study shows that CaF2 and NiO are the significant factors for tensile strength while FeMn is not significant for tensile strength. However, for elongation besides CaF2, the interaction of CaF2 and FeMn was also found significant. The effects of basicity index of the flux and carbon equivalent of the welds on tensile strength and percentage elongation of the welds have also been evaluated.

PL

W studium eksperymentalnym, przedstawionym w pracy, pokazano wpływ domieszek CaF2, FeMn i NiO do podstawowego składu topnika na wytrzymałość na rozciąganie i procentowe wydłużenie metalu spawu. Celem studium było opracowanie topnika odpowiedniego dla stali niskowęglowej, który zapewnia wysoką wytrzymałość na rozciąganie, wytrzymałość na udary i plastyczność. Ściegi spawów wykonano metodą spawania łukiem krytym. Opracowano model matematyczny wydłużenia procentowego i wytrzymałości na rozciąganie (UTS) dla spawów ze stali niskowęglowej. Zbadano korelację między wymienionymi charakterystykami mechanicznymi a transferem pierwiastków do spawu. Wyznaczono także wpływ zawartości tlenu na wydłużenie spawu i ostateczną wytrzymałość na rozciąganie. W badaniach doświadczalnych wykazano, że domieszki CaF2 oraz NiO są istotnymi czynnikami wpływającymi na wytrzymałość na rozciąganie, podczas gdy domieszka FeMn nie ma istotnego wpływu. Oceniono także wpływ współczynnika zasadowości topnika i równoważnika węglowego spawu na wydłużenie procentowe spawu.

11

Anomalous Variations of Ionosphere Associated with the Strong Earthquake at Pakistan-Iran Border at a Low Latitude Station Agra, India

Pundhir D., Singh B., Singh O. P., Gupta S. K.

Acta Geophysica

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2016

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Vol. 64, no. 3

796--809

EN

In this paper, we analyze the TEC data for April 2013 observed at Agra station, India (geogr. lat. 27.2° N, long. 78° E) to examine the effect of earthquake of magnitude M = 7.8 which occurred on 16 April 2013 at Pakistan–Iran border region. We process the TEC data using the σ statistical criterion to find out anomalous variation in TEC data. We also study the VLF propagation signal from NPM, Hawaii (21.42° N, 158° W), which is monitored at the same station (Agra station) in the light of this earthquake as well as solar flares. The nighttime fluctuation method is used to analyze the VLF data for the period of ±5 days from the day of earthquake (11-21 April 2013). The anomalous enhancements and depletions are found in TEC data on 1-9 days before the occurrence of event.

12

A Study of Early/Slow VLF Perturbations Observed at Agra, India

Pandey U., Singh A. K., Singh O. P., Singh B., Saraswat K.

Acta Geophysica

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2016

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Vol. 64, no. 3

755--771

EN

We present here the results of sub-ionospheric VLF perturbations observed on NWC (19.8 kHz) transmitter signal propagating in the Earth-ionosphere waveguide, monitored at our low latitude station Agra. During the period of observation (June-December 2011), we found 89 cases of VLF perturbation, while only 73 cases showing early character associated with strong lightning discharges. Out of 73 events, 64 (~84%) of the early VLF perturbations are found to be early/slow in nature; the remaining 9 events are early/fast. The onset duration of these early/slow VLF perturbations is up to ~ 5 s. A total of 54 observed early events show amplitude change lying between ± 3.0 dB, and phase change ± 12 degree, respectively, and found to occur mainly during nighttime. One of the interesting results we found is that the events with larger recovery time lie far away from the VLF propagation path, while events with smaller duration of recovery are within the ± 50-100 km of signal path. The World Wide Lightning Location Network (WWLLN) data is analysed to find the location of causative lightning and temporal variation. The lightning discharge and associated processes that lead to early VLF events are discussed.

13

Fixed point theorems for Kannan type mappings in 2-menger spaces

Gupta V., Singh B., Kumar S.

Fasciculi Mathematici

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2015

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Nr 54

97--115

EN

In this paper we show that the results of Choudhary and Das [2] hold under more general situation.

14

Reflection of plane waves from a free surface of a generalized magneto-thermoelastic solid half-space with diffusion

Singh B., Singh L., Deswal S.

Journal of Theoretical and Applied Mechanics

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2014

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Vol. 52 nr 2

385--394

EN

Green-Naghdi’s theory of generalized thermoelasticity is applied to study the reflection of P and SV waves from the free surface of a magneto-thermoelastic solid half-space. The boundary conditions are satisfied by appropriate potential functions to obtain a system of four non-homogeneous equations in reflection coefficients. The reflection coefficients depend upon the angle of incidence of P and SV waves, magnetic field, thermal field, diffusion parameters and other material constants. The numerical values of the modulus of the reflection coefficients are shown graphically with the angle of incidence of P and SV waves. The effect of magnetic field is observed significantly on various reflected waves.

15

New Control Algorithms for Three-Phase Four-Wire Unified Power Quality Conditioner - a simulation study

Pal Y., Swarup A., Singh B.

Electrical Power Quality and Utilisation. Journal

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2013

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Vol. 16, iss. 1

1--10

EN

In this paper, some new control algorithms are proposed for a three-phase four-wire Unified Power Quality Conditioner. These control algorithms are based on the combination of Unit Vector Template Generation (UVTG) with Power Balance Theory (PBT), single phase d-q theory, Synchronous Current Detection (CSD) technique, and I CosΦ theory. The performance of each control algorithm of UPQC is evaluated in terms of power factor correction, load balancing and source neutral current mitigation, and voltage and current harmonic mitigation. The performance of proposed control algorithms are compared with synchronous reference frame (SRF) based control algorithm. In each proposed control scheme of the three-phase four-wire UPQC, the current/voltage control is applied over the fundamental supply currents/ load voltages instead of fast changing APFs currents/ voltages, thereby reducing the effects of computational delay. Moreover, the load neutral or shunt APF neutral currents are not sensed hence the required current sensors are reduced. MATLAB/ Simulink based simulations are obtained, which support the functionality of the UPQC.

16

Cone 2-metric space and Fixed point theorem of contractive mappings

Singh B., Jain S., Bhagat P.

Commentationes Mathematicae

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2012

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Vol. 52, [Z] 2

143--151

EN

In this paper we introduce cone 2-metric space and prove some fixed point theorems of a contractive mapping on a cone 2-metric spaces.

17

On Rayleigh wave in generalized magneto-thermoelastic media with hydrostatic initial stress

Singh B., Kumari S., Singh J.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2012

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Vol. 60, nr 2

349-352

EN

The governing equations of generalized magneto-thermoelasticity with hydrostatic initial stress are solved for surface wave solutions. The particular solutions in the half-space are applied to the boundary conditions at the free surface of the half-space to obtain the frequency equation of Rayleigh wave. The frequency equation is approximated for small thermal coupling and small reduced frequency. The velocity of propagation and amplitude-attenuation factor of Rayleigh wave are computed numerically for a particular material. Effects of magnetic field and hydrostatic initial stress on the velocity of the propagation and amplitude-attenuation factor are shown graphically.

18

On common fixed point theorems for semi-compatible mappings in Menger space

Singh B., Jain A., Lodha B.

Commentationes Mathematicae

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2010

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Vol. 50, [Z] 2

127-139

EN

In this paper, the concept of semi-compatibility and weak compatibility in Menger space has been applied to prove a common fixed point theorem for six self maps. Our result generalizes and extends the result of Pathak and Verma [6].

19

Thermoelastic waves at an interface between two solid half-spaces under hydrostatic initial stress

Singh B., Singh J., Ailawalia P.

Archives of Mechanics

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2010

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Vol. 62, nr 3

177-193

EN

A model of two semi-infinite half-spaces of different thermoelastic solids is considered in welded contact under hydrostatic initial stress. The appropriate boundary conditions are satisfied at the interface to obtain the reflection and refraction coefficients of various reflected and refracted waves during incidence of the quasi-thermal wave. A particular numerical example is considered to show the effect of hydrostatic initial stress on these coefficients for a certain range of the angle of incidence.

20

Vector Controlled Induction Motor Drive Using Genetic Algorithm Tuned PI Speed Controller

Dey A., Singh B., Dwivedi B., Chandra D.

Electrical Power Quality and Utilisation. Journal

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2009

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Vol. 15, iss. 1

3--8

EN

In (his paper, timing and optimization of the proportional and integral (PI) gains of speed controller is achieved using Genetic Algorithm (GA) for improving the performance of the induction motor drive because higher the quality of the controller lesser is the ripples produced in the torque and speed responses. The developed GA program has multi-objective minimization functions. The optimized values of PI gains are incorporated in vector controlled induction motor model for performance analysis during sudden disturbances like speed reversal, load application and load removal. GA tuning method outstandingly surpasses the conventional and most widely used Ztegler Nichols Tuning method. GA tuned PI controller reduces the peak overshoot almost by 60% and quickly brings the system to steady state value. The simulated results obtained from GA tuned PI controller can be realized and validated through experimental results in future work.