Search results for: Nikhil Kumar Singha
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1689

Search results for: Nikhil Kumar Singha

1659 Potentially Inappropriate Prescribing in Elderly Population

Authors: Ajit Kumar Sah, Rajesh Kumar Jha, Phoolgen Sah, Dev Kumar Shah

Abstract:

Older individuals often suffer from multiple systemic diseases and are particularly more vulnerable to potentially inappropriate medicine prescribing. Inappropriate medication can cause serious medical problem for the elderly. The purpose of this study was to determine the prevalence of potentially inappropriate medicine (PIM) prescribing in older Nepalese patients in a medicine outpatient department. Beers’ criteria are the most widely used tools to assess PIM to elderly patients. Prospective observational analysis of drugs prescribed in medicine out-patient department (OPD) of a hospital of Bharatpur, Chitwan, Nepal during November 2011 to October 2012 to 869 older adults aged 65 years and above. The use of potentially inappropriate medications (PIM) in elderly patients was analyzed using Beers Criteria updated to 2013. In the 869 patients included the average number of drugs prescribed per prescription was 5.56. The most commonly used drugs were atenolol (24.3%), amlodipine (23.16%), paracetamol (17.6%), salbutamol (15.72%) and vitamin B complex (13.26%). The total number of medications prescribed was 4833. At least one instance of PIM was experienced by approximately 26.3% of patients when evaluated using the Beers criteria. Potentially inappropriate medications are highly prevalent among older patients attending medical OPD and are associated with a number of medications prescribed. Further research is warranted to study the impact of PIMs towards health-related outcomes in these elderly.

Keywords: Beers criteria, elderly, polypharmacy, potentially inappropriate medicines

Procedia PDF Downloads 532
1658 Modulational Instability of Ion-Acoustic Wave in Electron-Positron-Ion Plasmas with Two-Electron Temperature Distributions

Authors: Jitendra Kumar Chawla, Mukesh Kumar Mishra

Abstract:

The nonlinear amplitude modulation of ion-acoustic wave is studied in the presence of two-electron temperature distribution in unmagnetized electron-positron-ion plasmas. The Krylov-Bogoliubov-Mitropolosky (KBM) perturbation method is used to derive the nonlinear Schrödinger equation. The dispersive and nonlinear coefficients are obtained which depend on the temperature and concentration of the hot and cold electron species as well as the positron density and temperature. The modulationally unstable regions are studied numerically for a wide range of wave number. The effects of the temperature and concentration of the hot and cold electron on the modulational stability are investigated in detail.

Keywords: modulational instability, ion acoustic wave, KBM method

Procedia PDF Downloads 626
1657 Designing Expressive Behaviors to Improve Human-Robot Relationships

Authors: Sahil Anand, John Luetke, Nikhil Venkatesh, Dorothy Wong

Abstract:

Trust plays an important role in building and sustaining long-term relationships between people. In this paper, we present a robot that communicates using nonverbal behaviors such as facial expressions and body movements. Our study reports on an experiment in which participants were asked to team up with the robot to perform specific tasks. We varied the expressivity of the robot and measured the effects on trust, quality of interactions as well as on the praising and punishing behavior of the participant towards the robot. We found that participants developed a stronger affinity towards the expressive robot, but did not show any significant differences in the level of trust. When the same robot made mistakes, participants unconsciously punished it with lesser intensity compared to the neutral robot. The results emphasize the role of expressive behaviors on participant’s perception of the robot and also on the quality of interactions between humans and robots.

Keywords: human-robot interaction, nonverbal communication, relationships, social robot, trust

Procedia PDF Downloads 332
1656 Evaluation of High Temperature Wear Performance of as Cladded and Tig Re-Melting Stellite 6 Cladded Overlay on Aisi-304L Using SMAW Process

Authors: Manjit Singha, Sandeep Singh Sandhu, A. S. Shahi

Abstract:

Stellite 6 is cobalt based superalloy used for protective coatings. It is used to improve the wear performance of stainless steel engineering components subjected to harsh environmental conditions. This paper reports the high temperature wear analysis of satellite 6 cladded on AISI 304 L substrate using SMAW process. Bead on plate experiment was carried out by varying current and electrode manipulation techniques to optimize the dilution and hardness. 80 Amp current and weaving technique was found to be the optimum set of parameters for overlaying which were further used for multipass multilayer cladding on two plates of AISI 304 L substrate. On the first plate, seven layers seven passes of stellite 6 was overlaid which was used in as cladded form and the second plate was overlaid with five layers five passes of satellite 6 with further TIG remelting. The wear performance was examined for normal temperature environmental condition and harsh temperature environmental condition. The satellite 6 coating with TIG remelting was found to be better in both the conditions even with lesser metal deposition due to its finer grain structure.

Keywords: surfacing, stellite 6, dilution, overlay, SMAW, high-temperature frictional wear, micro-structure, micro-hardness

Procedia PDF Downloads 261
1655 Temperature Dependent Tribological Properties of Graphite

Authors: Pankaj Kumar Das, Niranjan Kumar, Prasun Chakraborti

Abstract:

Temperature dependent tribologiocal properties of nuclear grade turbostatic graphite were studied using 100Cr6 steel counterbody. High value of friction coefficient (0.25) and high wear loss was observed at room temperature and this value decreased to 0.1 at 150oC. Consequently, wear loss is also decreased. Such behavior is explained by oxidation/vaporization of graphite and water molecules. At room temperature, the adsorbed water in graphite does not decompose and effect of passivation mechanism does not work. However, at 150oC, the water decomposed into OH, atomic hydrogen and oxygen which efficiently passivates the carbon dangling bonds. This effect is known to decrease the energy of the contact and protect against abrasive wear.

Keywords: high temperature tribology, oxidation, turbostratic graphite, wear

Procedia PDF Downloads 466
1654 Modeling and Simulation of Underwater Flexible Manipulator as Raleigh Beam Using Bond Graph

Authors: Sumit Kumar, Sunil Kumar, Chandan Deep Singh

Abstract:

This paper presents modeling and simulation of flexible robot in an underwater environment. The underwater environment completely contrasts with ground or space environment. The robot in an underwater situation is subjected to various dynamic forces like buoyancy forces, hydrostatic and hydrodynamic forces. The underwater robot is modeled as Rayleigh beam. The developed model further allows estimating the deflection of tip in two directions. The complete dynamics of the underwater robot is analyzed, which is the main focus of this investigation. The control of robot trajectory is not discussed in this paper. Simulation is performed using Symbol Shakti software.

Keywords: bond graph modeling, dynamics. modeling, rayleigh beam, underwater robot

Procedia PDF Downloads 555
1653 Dielectric Behavior of 2D Layered Insulator Hexagonal Boron Nitride

Authors: Nikhil Jain, Yang Xu, Bin Yu

Abstract:

Hexagonal boron nitride (h-BN) has been used as a substrate and gate dielectric for graphene field effect transistors (GFETs). Using a graphene/h-BN/TiN (channel/dielectric/gate) stack, key material properties of h-BN were investigated i.e. dielectric strength and tunneling behavior. Work function difference between graphene and TiN results in spontaneous p-doping of graphene through a multi-layer h-BN flake. However, at high levels of current stress, n-doping of graphene is observed, possibly due to the charge transfer across the thin h-BN multi layer. Neither Direct Tunneling (DT) nor Fowler-Nordheim Tunneling (FNT) was observed in TiN/h-BN/Au hetero structures with h-BN showing two distinct volatile conduction states before breakdown. Hexagonal boron nitride emerges as a material of choice for gate dielectrics in GFETs because of robust dielectric properties and high tunneling barrier.

Keywords: graphene, transistors, conduction, hexagonal boron nitride, dielectric strength, tunneling

Procedia PDF Downloads 330
1652 Assessment of Power Formation in Gas Turbine Power Plants Using Different Inlet Air Cooling Systems

Authors: Nikhil V. Nayak

Abstract:

In this paper, the influence of air cooling intake on the gas turbine performance is presented. A comparison among different cooling systems, i.e., evaporative and cooling coil, is performed. A computer simulation model for the employed systems is developed in order to evaluate the performance of the studied gas turbine unit, at Marka Power Station, Amman, Bangalore. The performance characteristics are examined for a set of actual operational parameters including ambient temperature, relative humidity, turbine inlet temperature, pressure ratio, etc. The obtained results showed that the evaporative cooling system is capable of boosting the power and enhancing the efficiency of the studied gas turbine unit in a way much cheaper than cooling coil system due to its high power consumption required to run the vapor-compression refrigeration unit. Nevertheless, it provides full control on the temperature inlet conditions regardless of the relative humidity ratio.

Keywords: power augmentation, temperature control, evaporative cooling, cooling coil, gas turbine

Procedia PDF Downloads 357
1651 Dynamic Relaxation and Isogeometric Analysis for Finite Deformation Elastic Sheets with Combined Bending and Stretching

Authors: Nikhil Padhye, Ellen Kintz, Dan Dorci

Abstract:

Recent years have seen a rising interest in study and applications of materially uniform thin-structures (plates/shells) subject to finite-bending and stretching deformations. We introduce a well-posed 2D-model involving finite-bending and stretching of thin-structures to approximate the three-dimensional equilibria. Key features of this approach include: Non-Uniform Rational B-Spline (NURBS)-based spatial discretization for finite elements, method of dynamic relaxation to predict stable equilibria, and no a priori kinematic assumption on the deformation fields. The approach is validated against the benchmark problems,and the use of NURBS for spatial discretization facilitates exact spatial representation and computation of curvatures (due to C1-continuity of interpolated displacements) for this higher-order accuracy 2D-model.

Keywords: Isogeometric Analysis, Plates/Shells , Finite Element Methods, Dynamic Relaxation

Procedia PDF Downloads 132
1650 To Individualisation of Subject, Donar, by Determination of Serological Markers from Obtain Biological Fluid at Crime Scene

Authors: Arun Kumar, Ravindra Pal Verma, Harsh Sharma, Shani Kumar

Abstract:

For the present study samples was collected from 20 donors with unknown blood group and secretor status had been determined from saliva by using biological fluid. ABO typing on the concentrated samples was successfully performed after 1 month of storage. Urine stained clothing samples are often submitted to forensic science laboratories for ABH blood group antigen determination. The serogenetic markers of semen stains submitted can be used to determine the origin of any of these samples. ABH blood group substances have previously been identified from urine. ABH blood group substance is low in urine in comparison with other body fluids.

Keywords: ABH blood group, crime scene, serological markers, body fluids and urine

Procedia PDF Downloads 549
1649 Biosorption of Phenol onto Water Hyacinth Activated Carbon: Kinetics and Isotherm Study

Authors: Manoj Kumar Mahapatra, Arvind Kumar

Abstract:

Batch adsorption experiments were carried out for the removal of phenol from its aqueous solution using water hyancith activated carbon (WHAC) as an adsorbent. The sorption kinetics were analysed using pseudo-first order kinetics and pseudo-second order model, and it was observed that the sorption data tend to fit very well in pseudo-second order model for the entire sorption time. The experimental data were analyzed by the Langmuir and Freundlich isotherm models. Equilibrium data fitted well to the Freundlich model with a maximum biosorption capacity of 31.45 mg/g estimated using Langmuir model. The adsorption intensity 3.7975 represents a favorable adsorption condition.

Keywords: adsorption, isotherm, kinetics, phenol

Procedia PDF Downloads 421
1648 Graphene/h-BN Heterostructure Interconnects

Authors: Nikhil Jain, Yang Xu, Bin Yu

Abstract:

The material behavior of graphene, a single layer of carbon lattice, is extremely sensitive to its dielectric environment. We demonstrate improvement in electronic performance of graphene nanowire interconnects with full encapsulation by lattice-matching, chemically inert, 2D layered insulator hexagonal boron nitride (h- BN). A novel layer-based transfer technique is developed to construct the h-BN/MLG/h-BN heterostructures. The encapsulated graphene wires are characterized and compared with that on SiO2 or h-BN substrate without passivating h-BN layer. Significant improvements in maximum current-carrying density, breakdown threshold, and power density in encapsulated graphene wires are observed. These critical improvements are achieved without compromising the carrier transport characteristics in graphene. Furthermore, graphene wires exhibit electrical behavior less insensitive to ambient conditions, as compared with the non-passivated ones. Overall, h-BN/graphene/h- BN heterostructure presents a robust material platform towards the implementation of high-speed carbon-based interconnects.

Keywords: two-dimensional nanosheet, graphene, hexagonal boron nitride, heterostructure, interconnects

Procedia PDF Downloads 296
1647 Field Experience with Sweep Frequency Response Analysis for Power Transformer Diagnosis

Authors: Ambuj Kumar, Sunil Kumar Singh, Shrikant Singh, Zakir Husain, R. K. Jarial

Abstract:

Sweep frequency response analysis has been turning out a powerful tool for investigation of mechanical as well as electrical integration of transformers. In this paper various aspect of practical application of SFRA has been studied. Open circuit and short circuit measurement were done on different phases of high voltage and low voltage winding. A case study was presented for the transformer of rating 31.5 MVA for various frequency ranges. A clear picture was presented for sub- frequency ranges for HV as well as LV winding. The main motive of work is to investigate high voltage short circuit response. The theoretical concept about SFRA responses is validated with expert system software results.

Keywords: transformer winding, SFRA, OCT & SCT, frequency deviation

Procedia PDF Downloads 926
1646 Oil Producing Wells Using a Technique of Gas Lift on Prosper Software

Authors: Nikhil Yadav, Shubham Verma

Abstract:

Gas lift is a common technique used to optimize oil production in wells. Prosper software is a powerful tool for modeling and optimizing gas lift systems in oil wells. This review paper examines the effectiveness of Prosper software in optimizing gas lift systems in oil-producing wells. The literature review identified several studies that demonstrated the use of Prosper software to adjust injection rate, depth, and valve characteristics to optimize gas lift system performance. The results showed that Prosper software can significantly improve production rates and reduce operating costs in oil-producing wells. However, the accuracy of the model depends on the accuracy of the input data, and the cost of Prosper software can be high. Therefore, further research is needed to improve the accuracy of the model and evaluate the cost-effectiveness of using Prosper software in gas lift system optimization

Keywords: gas lift, prosper software, injection rate, operating costs, oil-producing wells

Procedia PDF Downloads 45
1645 The First Complete Mitochondrial Genome of Melon Thrips, Thrips palmi (Thripinae: Thysanoptera): Vector for Tospoviruses

Authors: Kaomud Tyagi, Rajasree Chakraborty, Shantanu Kundu, Devkant Singha, Kailash Chandra, Vikas Kumar

Abstract:

The melon thrips, Thrips palmi is a serious pest of a wide range of agriculture crops and also act as vectors for plant viruses (genus Tospovirus, family Bunyaviridae). More molecular data on this species is required to understand the cryptic speciation and evolutionary affiliations. Mitochondrial genomes have been widely used in phylogenetic and evolutionary studies in insect. So far, mitogenomes of five thrips species (Anaphothrips obscurus, Frankliniella intonsa, Frankliniella occidentalis, Scirtothrips dorsalis and Thrips imaginis) is available in the GenBank database. In this study, we sequenced the first complete mitogenome T. palmi and compared it with available thrips mitogenomes. We assembled the mitogenome from the whole genome sequencing data generated using Illumina Hiseq2500. Annotation was performed using MITOS web-server to estimate the location of protein coding genes (PCGs), transfer RNA (tRNAs), ribosomal RNAs (rRNAs) and their secondary structures. The boundaries of PCGs and rRNAs was confirmed manually in NCBI. Phylogenetic analyses were performed using the 13 PCGs data using maximum likelihood (ML) in PAUP, and Bayesian inference (BI) in MrBayes 3.2. The complete mitogenome of T. palmi was 15,333 base pairs (bp), which was greater than the genomes of A. obscurus (14,890bp), F. intonsa (15,215 bp), F. occidentalis (14,889 bp) and S. dorsalis South Asia strain (SA1) (14,283 bp), but smaller than the genomes of T. imaginis (15,407 bp) and S. dorsalis East Asia strain (EA1) (15,343bp). Like in other thrips species, the mitochondrial genome of T. palmi was represented by 37 genes, including 13 PCGs, large and small ribosomal RNA (rrnL and rrnS) genes, 22 transfer RNA (tRNAs) genes (with one extra gene for trn-Serine) and two A+T-rich control regions (CR1 and CR2). Thirty one genes were observed on heavy (H) strand and six genes on the light (L) strand. The six tRNA genes (trnG,trnK, trnY, trnW, trnF, and trnH) were found to be conserved in all thrips species mitogenomes in their locations relative to a protein-coding or rRNA gene upstream or downstream. The gene arrangements of T. palmi is very close to T. imaginis except the rearrangements in tRNAs genes: trnR (arginine), and trnE (glutamic acid) were found to be located between cox3 and CR2 in T. imaginis which were translocated between atp6 and CR1 in T. palmi; trnL1 (Leucine) and trnS1(Serine) were located between atp6 and CR1 in T. imaginis which were translocated between cox3 and CR2 in T. palmi. The location of CR1 upstream of nad5 gene was suggested to be ancestral condition of the thrips species in subfamily Thripinae, was also observed in T. palmi. Both the Maximum likelihood (ML) and Bayesian Inference (BI) phylogenetic trees generated resulted in similar topologies. The T. palmi was clustered with T. imaginis. We concluded that more molecular data on the diverse thrips species from different hierarchical level is needed, to understand the phylogenetic and evolutionary relationships among them.

Keywords: thrips, comparative mitogenomics, gene rearrangements, phylogenetic analysis

Procedia PDF Downloads 139
1644 Two-Dimensional Nanostack Based On Chip Wiring

Authors: Nikhil Jain, Bin Yu

Abstract:

The material behavior of graphene, a single layer of carbon lattice, is extremely sensitive to its dielectric environment. We demonstrate improvement in electronic performance of graphene nanowire interconnects with full encapsulation by lattice-matching, chemically inert, 2D layered insulator hexagonal boron nitride (h-BN). A novel layer-based transfer technique is developed to construct the h-BN/MLG/h-BN heterostructures. The encapsulated graphene wires are characterized and compared with that on SiO2 or h-BN substrate without passivating h-BN layer. Significant improvements in maximum current-carrying density, breakdown threshold, and power density in encapsulated graphene wires are observed. These critical improvements are achieved without compromising the carrier transport characteristics in graphene. Furthermore, graphene wires exhibit electrical behavior less insensitive to ambient conditions, as compared with the non-passivated ones. Overall, h-BN/graphene/h-BN heterostructure presents a robust material platform towards the implementation of high-speed carbon-based interconnects.

Keywords: two-dimensional nanosheet, graphene, hexagonal boron nitride, heterostructure, interconnects

Procedia PDF Downloads 421
1643 A Double Epilayer PSGT Trench Power MOSFETs for Low to Medium Voltage Power Applications

Authors: Alok Kumar Kamal, Vinod Kumar

Abstract:

The trench gate MOSFET has shown itself as the most appropriate power device for low to medium voltage power applications due to its lowest possible ON resistance among all power semiconductor devices. In this research work a double-epilayer PSGT structure using a thin layer of N+ polysilicon as gate material. The total ON-state resistance (RON) of UMOSFET can be reduced by optimizing the epilayer thickness. The optimized structure of Double-Epilayer exhibits a 25.8% reduction in the ON-state resistance at Vgs=5V and improving the switching characteristics by reducing the Reverse transfer capacitance (Cgd) by 7.4%.

Keywords: Miller-capacitance, double-Epilayer;switching characteristics, power trench MOSFET (U-MOSFET), on-state resistance, blocking voltage

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1642 Extraction of Strontium Ions through Ligand Assisted Ionic Liquids

Authors: Pradeep Kumar, Abhishek Kumar Chandra, Ashok Khanna

Abstract:

Extraction of Strontium by crown ether (DCH18C6) hasbeen investigated in [BMIM][TF2N] Ionic Liquid (IL) giving higher extraction ~98% and distribution ratio as compared to other organic solvents (Dodecane, Hexane, & Isodecyl alcohol + Dodecane). Distribution ratio of Sr in IL at 0.15M DCH18C6 indicates an enhancement of 20000, 2000, 500 times over Dodecane, Hexane and 5% Isodecyl Alcohol + 95 % Dodecane at 0.01M aqueous acidity respectively. In presence of IL, Sr extraction decreases with increase in HNO3 concentration in aqueous phase whereas opposite trend was observed with organic solvents.Extraction of Sr initially increases with increase in DCH18C6 concentration in IL, finally reaching an asymptotic constant.

Keywords: distribution ratio, ionic liquid, ligand, organic solvent, stripping

Procedia PDF Downloads 412
1641 Surface Roughness Effects in Pure Sliding EHL Line Contacts with Carreau-Type Shear-Thinning Lubricants

Authors: Punit Kumar, Niraj Kumar

Abstract:

The influence of transverse surface roughness on EHL characteristics has been investigated numerically using an extensive set of full EHL line contact simulations for shear-thinning lubricants under pure sliding condition. The shear-thinning behavior of lubricant is modeled using Carreau viscosity equation along with Doolittle-Tait equation for lubricant compressibility. The surface roughness is assumed to be sinusoidal and it is present on the stationary surface. It is found that surface roughness causes sharp pressure peaks along with reduction in central and minimum film thickness. With increasing amplitude of surface roughness, the minimum film thickness decreases much more rapidly as compared to the central film thickness.

Keywords: EHL, Carreau, shear-thinning, surface roughness, amplitude, wavelength

Procedia PDF Downloads 698
1640 A Review of Fractal Dimension Computing Methods Applied to Wear Particles

Authors: Manish Kumar Thakur, Subrata Kumar Ghosh

Abstract:

Various types of particles found in lubricant may be characterized by their fractal dimension. Some of the available methods are: yard-stick method or structured walk method, box-counting method. This paper presents a review of the developments and progress in fractal dimension computing methods as applied to characteristics the surface of wear particles. An overview of these methods, their implementation, their advantages and their limits is also present here. It has been accepted that wear particles contain major information about wear and friction of materials. Morphological analysis of wear particles from a lubricant is a very effective way for machine condition monitoring. Fractal dimension methods are used to characterize the morphology of the found particles. It is very useful in the analysis of complexity of irregular substance. The aim of this review is to bring together the fractal methods applicable for wear particles.

Keywords: fractal dimension, morphological analysis, wear, wear particles

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1639 Design and Optimization of a Mini High Altitude Long Endurance (HALE) Multi-Role Unmanned Aerial Vehicle

Authors: Vishaal Subramanian, Annuatha Vinod Kumar, Santosh Kumar Budankayala, M. Senthil Kumar

Abstract:

This paper discusses the aerodynamic and structural design, simulation and optimization of a mini-High Altitude Long Endurance (HALE) UAV. The applications of this mini HALE UAV vary from aerial topological surveys, quick first aid supply, emergency medical blood transport, search and relief activates to border patrol, surveillance and estimation of forest fire progression. Although classified as a mini UAV according to UVS International, our design is an amalgamation of the features of ‘mini’ and ‘HALE’ categories, combining the light weight of the ‘mini’ and the high altitude ceiling and endurance of the HALE. Designed with the idea of implementation in India, it is in strict compliance with the UAS rules proposed by the office of the Director General of Civil Aviation. The plane can be completely automated or have partial override control and is equipped with an Infra-Red camera and a multi coloured camera with on-board storage or live telemetry, GPS system with Geo Fencing and fail safe measures. An additional of 1.5 kg payload can be attached to three major hard points on the aircraft and can comprise of delicate equipment or releasable payloads. The paper details the design, optimization process and the simulations performed using various software such as Design Foil, XFLR5, Solidworks and Ansys.

Keywords: aircraft, endurance, HALE, high altitude, long range, UAV, unmanned aerial vehicle

Procedia PDF Downloads 373
1638 Hydro-Chemical Characterization of Glacial Melt Waters Draining from Shaune Garang Glacier, Himachal Himalaya

Authors: Ramesh Kumar, Rajesh Kumar, Shaktiman Singh, Atar Singh, Anshuman Bhardwaj, Ravindra Kumar Sinha, Anupma Kumari

Abstract:

A detailed study of the ion chemistry of the Shaune Garnag glacier meltwater has been carried out to assess the role of active glacier in the chemical denudation rate. The chemical compositions of various ions in meltwater of the Shaune Garang glacier were analyzed during the melting period 2015 and 2016. Total 112 of melt water samples twice in a day were collected during ablation season of 2015 and 2016. To identify various factors controlling the dissolved ionic strength of Shaune Garang Glacier meltwater statistical analysis such as correlation matrix, Principle Component Analysis (PCA) and factor analysis were applied to deduce the result. Cation concentration for Ca²⁺ > Mg²⁺ > Na⁺ > K⁺ in the meltwater for both the years can be arranged in the order as Ca²⁺ > Mg²⁺ > Na⁺ > K⁺. Study showed that Ca²⁺ and HCO₃⁻ found to be dominant on the both melting period. Carbonate weathering identified as the dominant process controlling the dissolved ion chemistry of meltwater due to the high ratios of (Ca²⁺ + Mg²⁺) versus TZ+ and (Ca²⁺ + Mg²⁺) versus (Na⁺ + K⁺) in the study area. The cation denudation rate of the Shaune Garnag catchment is 3412.2 m⁻² a⁻¹, i.e. higher than the other glacierised catchment in the Himalaya, indicating intense chemical erosion in this catchment.

Keywords: Shaune Garang glacier, Hydrochemistry, chemical composition, cation denudation rate, carbonate weathering

Procedia PDF Downloads 342
1637 Comparison of Different Methods of Evaluating Nozzle Junction Stresses under External Loads

Authors: Vinod Kumar, Arun Kumar, Surjit Angra

Abstract:

This paper addresses the junction stress analysis of orthogonally intersecting thin walled cylindrical shell and thin walled cylindrical nozzle subjected to external loading on nozzle. Junction stresses have been calculated theoretically by welding research council (WRC) bulletins 107 and 297 for different nozzle loads. WRC bulletins 107 and 297 have been used by design engineers for calculating nozzle-vessel junction stresses since their publication. They give simple empirical relations and easy in application. Also 3D FEA in which material is elastic has been done in ANSYS software with 8 node solid element model and results of FEA have been compared with WRC results. Stress intensities obtained by WRC 297 are generally slightly higher than obtained by WRC 107. Membrane stresses obtained by FEA are much higher than WRC and membrane plus bending stresses obtained by FEA are lower than WRC.

Keywords: FEA, junction stress, solid element, WRC 107, WRC 297

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1636 Performance and Emissions Analysis of Diesel Engine with Bio-Diesel of Waste Cooking Oils

Authors: Mukesh Kumar, Onkar Singh, Naveen Kumar, Amar Deep

Abstract:

The waste cooking oil is taken as feedstock for biodiesel production. For this research, waste cooking oil is collected from many hotels and restaurants, and then biodiesel is prepared for experimentation purpose. The prepared biodiesel is mixed with mineral diesel in the proportion of 10%, 20%, and 30% to perform tests on a diesel engine. The experimental analysis is carried out at different load conditions to analyze the impact of the blending ratio on the performance and emission parameters. When the blending proportion of biodiesel is increased, then the highest pressure reduces due to the fall in the calorific value of the blended mixture. Experimental analysis shows a promising decrease in nitrogen oxides (NOx). A mixture of 20% biodiesel and mineral diesel is the best negotiation, mixing ratio, and beyond that, a remarkable reduction in the outcome of the performance has been observed.

Keywords: alternative sources, diesel engine, emissions, performance

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1635 Dynamic Soil Structure Interaction in Buildings

Authors: Shreya Thusoo, Karan Modi, Ankit Kumar Jha, Rajesh Kumar

Abstract:

Since the evolution of computational tools and simulation software, there has been considerable increase in research on Soil Structure Interaction (SSI) to decrease the computational time and increase accuracy in the results. To aid the designer with a proper understanding of the response of structure in different soil types, the presented paper compares the deformation, shear stress, acceleration and other parameters of multi-storey building for a specific input ground motion using Response-spectrum Analysis (RSA) method. The response of all the models of different heights have been compared in different soil types. Finite Element Simulation software, ANSYS, has been used for all the computational purposes. Overall, higher response is observed with SSI, while it increases with decreasing stiffness of soil.

Keywords: soil-structure interaction, response spectrum, analysis, finite element method, multi-storey buildings

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1634 Improved Predictive Models for the IRMA Network Using Nonlinear Optimisation

Authors: Vishwesh Kulkarni, Nikhil Bellarykar

Abstract:

Cellular complexity stems from the interactions among thousands of different molecular species. Thanks to the emerging fields of systems and synthetic biology, scientists are beginning to unravel these regulatory, signaling, and metabolic interactions and to understand their coordinated action. Reverse engineering of biological networks has has several benefits but a poor quality of data combined with the difficulty in reproducing it limits the applicability of these methods. A few years back, many of the commonly used predictive algorithms were tested on a network constructed in the yeast Saccharomyces cerevisiae (S. cerevisiae) to resolve this issue. The network was a synthetic network of five genes regulating each other for the so-called in vivo reverse-engineering and modeling assessment (IRMA). The network was constructed in S. cereviase since it is a simple and well characterized organism. The synthetic network included a variety of regulatory interactions, thus capturing the behaviour of larger eukaryotic gene networks on a smaller scale. We derive a new set of algorithms by solving a nonlinear optimization problem and show how these algorithms outperform other algorithms on these datasets.

Keywords: synthetic gene network, network identification, optimization, nonlinear modeling

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1633 A Novel Method for Silence Removal in Sounds Produced by Percussive Instruments

Authors: B. Kishore Kumar, Rakesh Pogula, T. Kishore Kumar

Abstract:

The steepness of an audio signal which is produced by the musical instruments, specifically percussive instruments is the perception of how high tone or low tone which can be considered as a frequency closely related to the fundamental frequency. This paper presents a novel method for silence removal and segmentation of music signals produced by the percussive instruments and the performance of proposed method is studied with the help of MATLAB simulations. This method is based on two simple features, namely the signal energy and the spectral centroid. As long as the feature sequences are extracted, a simple thresholding criterion is applied in order to remove the silence areas in the sound signal. The simulations were carried on various instruments like drum, flute and guitar and results of the proposed method were analyzed.

Keywords: percussive instruments, spectral energy, spectral centroid, silence removal

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1632 Graphene Transistor Employing Multilayer Hexagonal Boron Nitride as Substrate and Gate Insulator

Authors: Nikhil Jain, Bin Yu

Abstract:

We explore the potential of using ultra-thin hexagonal boron nitride (h-BN) as both supporting substrate and gate dielectric for graphene-channel field effect transistors (GFETs). Different from commonly used oxide-based dielectric materials which are typically amorphous, very rough in surface, and rich with surface traps, h-BN is layered insulator free of dangling bonds and surface states, featuring atomically smooth surface. In a graphene-channel-last device structure with local buried metal gate electrode (TiN), thin h-BN multilayer is employed as both supporting “substrate” and gate dielectric for graphene active channel. We observed superior carrier mobility and electrical conduction, significantly improved from that in GFETs with SiO2 as substrate/gate insulator. In addition, we report excellent dielectric behavior of layered h-BN, including ultra-low leakage current and high critical electric field for breakdown.

Keywords: graphene, field-effect transistors, hexagonal boron nitride, dielectric strength, tunneling

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1631 Study the Sloshing Phenomenon in the Tank Filled Partially with Liquid Using Computational Fluid Dynamics (CFD) Simulation

Authors: Amit Kumar, Jaikumar V., Pradeep A. G., Shivakumar Bhavi

Abstract:

Amit Kumar, Jaikumar V, Pradeep AG, Shivakumar Bhavi Reducing sloshing is one of the major challenges in industries where transporting of liquid is involved. The present study investigates the sloshing effect for different liquid levels of 50% of the tank capacity. CFD simulation for two different baffle configurations has been carried out using a time-based multiphase Volume of fluid (VOF) scheme. Baffles were introduced to examine the sloshing effect inside the tank. Results were compared against the baseline case to assess the effectiveness of baffles; maximum liquid height over the period of the simulation was considered as the parameter for measuring the sloshing effect inside the tank. It was found that the addition of baffles reduced the sloshing effect inside the tank as compared to the baseline model.

Keywords: CFD, sloshing, VOF, multiphase

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1630 A Multi-Release Software Reliability Growth Models Incorporating Imperfect Debugging and Change-Point under the Simulated Testing Environment and Software Release Time

Authors: Sujit Kumar Pradhan, Anil Kumar, Vijay Kumar

Abstract:

The testing process of the software during the software development time is a crucial step as it makes the software more efficient and dependable. To estimate software’s reliability through the mean value function, many software reliability growth models (SRGMs) were developed under the assumption that operating and testing environments are the same. Practically, it is not true because when the software works in a natural field environment, the reliability of the software differs. This article discussed an SRGM comprising change-point and imperfect debugging in a simulated testing environment. Later on, we extended it in a multi-release direction. Initially, the software was released to the market with few features. According to the market’s demand, the software company upgraded the current version by adding new features as time passed. Therefore, we have proposed a generalized multi-release SRGM where change-point and imperfect debugging concepts have been addressed in a simulated testing environment. The failure-increasing rate concept has been adopted to determine the change point for each software release. Based on nine goodness-of-fit criteria, the proposed model is validated on two real datasets. The results demonstrate that the proposed model fits the datasets better. We have also discussed the optimal release time of the software through a cost model by assuming that the testing and debugging costs are time-dependent.

Keywords: software reliability growth models, non-homogeneous Poisson process, multi-release software, mean value function, change-point, environmental factors

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