Relevance vector based approach for the prediction of stress intensity factor for the pipe with circumferential crack under cyclic loading

A. Ramachandra Murthy,S. Vishnuvardhan,M. Saravanan,P. Gandhi 국제구조공학회 2019 Structural Engineering and Mechanics, An Int'l Jou Vol.72 No.1

Structural integrity assessment of piping components is of paramount important for remaining life prediction, residual strength evaluation and for in-service inspection planning. For accurate prediction of these, a reliable fracture parameter is essential. One of the fracture parameters is stress intensity factor (SIF), which is generally preferred for high strength materials, can be evaluated by using linear elastic fracture mechanics principles. To employ available analytical and numerical procedures for fracture analysis of piping components, it takes considerable amount of time and effort. In view of this, an alternative approach to analytical and finite element analysis, a model based on relevance vector machine (RVM) is developed to predict SIF of part through crack of a piping component under fatigue loading. RVM is based on probabilistic approach and regression and it is established based on Bayesian formulation of a linear model with an appropriate prior that results in a sparse representation. Model for SIF prediction is developed by using MATLAB software wherein 70% of the data has been used for the development of RVM model and rest of the data is used for validation. The predicted SIF is found to be in good agreement with the corresponding analytical solution, and can be used for damage tolerant analysis of structural components.

Prediction of stress intensity factor range for API 5L grade X65 steel by using GPR and MPMR

A. Ramachandra Murthy,S. Vishnuvardhan,M. Saravanan,P. Gandhi 국제구조공학회 2022 Structural Engineering and Mechanics, An Int'l Jou Vol.81 No.5

The infrastructures such as offshore, bridges, power plant, oil and gas piping and aircraft operate in a harsh environment during their service life. Structural integrity of engineering components used in these industries is paramount for the reliability and economics of operation. Two regression models based on the concept of Gaussian process regression (GPR) and Minimax probability machine regression (MPMR) were developed to predict stress intensity factor range (K). Both GPR and MPMR are in the frame work of probability distribution. Models were developed by using the fatigue crack growth data in MATLAB by appropriately modifying the tools. Fatigue crack growth experiments were carried out on Eccentrically-loaded Single Edge notch Tension (ESE(T)) specimens made of API 5L X65 Grade steel in inert and corrosive environments (2.0% and 3.5% NaCl). The experiments were carried out under constant amplitude cyclic loading with a stress ratio of 0.1 and 5.0 Hz frequency (inert environment), 0.5 Hz frequency (corrosive environment). Crack growth rate (da/dN) and stress intensity factor range (K) values were evaluated at incremental values of loading cycle and crack length. About 70 to 75% of the data has been used for training and the remaining for validation of the models. It is observed that the predicted SIF range is in good agreement with the corresponding experimental observations. Further, the performance of the models was assessed with several statistical parameters, namely, Root Mean Square Error (RMSE), Mean Absolute Error (MAE), Coefficient of Efficiency (E), Root Mean Square Error to Observation’s Standard Deviation Ratio (RSR), Normalized Mean Bias Error (NMBE), Performance Index (ρ) and Variance Account Factor (VAF).

Investigation of some Natural Product Extracts as Corrosion Inhibitors for Mild Steel in Acid Medium

( A. Subramania ),( A. R. Sathiya Priya ),( S. Saravanan ),( A. J. Abdul Nasser ),( T. Vasudevan ) 한국부식방식학회(구 한국부식학회) 2005 Corrosion Science and Technology Vol.4 No.6

Sexing of Sheep Embryos Produced In vitro by Polymerase Chain Reaction and Sex-specific Polymorphism

Saravanan, T.,Nainar, A. Mahalinga,Kumanan, K.,Kumaresan, A. Asian Australasian Association of Animal Productio 2003 Animal Bioscience Vol.16 No.5

The accuracy of Polymerase chain reaction (PCR) assay in sexing of sheep embryos was assessed in this study. A total of 174 ovine embryos produced in vitro at different stages of development (2, 4-8 cell stages, morula and blastocyst) were sexed. The universal primers (P1-5EZ and P2-3EZ) used in this assay amplified ZFY/ZFX-specific sequences and yielded a 445 bp fragment in both sexes. Restriction enzyme analysis of ZFY/ZFX-amplified fragments with Sac I exhibited polymorphism between sexes, three and two fragments in males and in females, respectively. For verification of accuracy, blood samples of known sex were utilized as positive controls in each test. The mean percentages of sex identification by this method at 2 cell, 4-8 cell, morula and blastocyst were $73.00{\pm}5.72$, $89.77{\pm}3.79$, $3.33{\pm}8.08$ and $79.6{\pm}9.09$, espectively with the over all male to female ratio of 1:0.87. It is concluded that the ZFY/ZFX based method is highly reliable for the sexing of sheep embryos.

Combined effects of magnetic and electric fields on the interband optical transitions in InAs/InP quantum wire

Saravanan, S.,John Peter, A.,Lee, ChangWoo Elsevier 2015 Physica E, Low-dimensional systems & nanostructure Vol.67 No.-

<P><B>Abstract</B></P> <P>Combined effects of magnetic and electric fields on the confined exciton in an InAs<SUB>1−<I>x</I> </SUB>P<I> <SUB>x</SUB> </I>/InP (<I>x</I>=0.2) quantum well wire are investigated taking into account the geometrical confinement effect. Variational formulism, within the frame work of effective mass approximation, is applied to obtain the exciton binding energy. The second order harmonic generation and the optical gain are carried out using compact density method. The strain effects are included with the confinement potential in the Hamiltonian. The energy difference of the ground and the first excited state is found in the presence of magnetic and electric fields taking into the consideration of spatial confinement effect. The result shows that the optical properties are more influenced taking into account the effects of geometrical confinement, magnetic field and electric field. It is shown that the telecommunication wavelength can be achieved with the suitable doping barrier material with the wire material and the external perturbations.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Combined effects of magnetic and electric fields on the confined exciton in an InAs<SUB>1−<I>x</I> </SUB>P<I> <SUB>x</SUB> </I>/InP wire are investigated. </LI> <LI> Variational formulism is applied to obtain the exciton binding energy. </LI> <LI> Second order harmonic generation and the optical gain are carried out using compact density method. </LI> <LI> The strain effects are included with the confinement potential in the Hamiltonian. </LI> <LI> Optical properties are more influenced with the effects of geometrical confinement and the external perturbations. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Variation of gain as a function of photon energy for various values of measure of magnetic field strength in a InAs<SUB>0.8</SUB>P<SUB>0.2</SUB>/InP quantum well wire is shown for <I>F</I>=0V/cm and <I>F</I>=100V/cm, with the constant electron density. The wire radius is taken as 50Å.</P> <P>[DISPLAY OMISSION]</P>

Multi‑State Reconfgurable Antenna for Wireless Communications

A. Priya,S. Kaja Mohideen,Manavalan Saravanan 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.1

A compact frequency and polarization reconfgurable antenna is presented. The antenna comprises of a truncated corner square patch along with two strip lines running parallel to it. The entire model is fabricated on single layer roger RO 4350 substrate. Pin diodes are used for switching frequency and polarization states. Two ports are used for switching polarization states. The antenna can achieve two frequency bands and four polarization states. The antenna model is fabricated and the measured results are compared with simulated results. The antenna achieves −10 dB impedance bandwidth of 100 MHz for LP state and 50 MHz for CP state and also the antenna attains good cross-polarization isolation of>15 dB in all states. The antenna gives a maximum measured gain of 5.48 dBi for linear polarization (LP) state and 4.82 dBi for circular polarization (CP) state.

The Implementation of Total Quality Management in Controlling the Cost of Manufacturing

A. Seetharaman,John Rudolph Raj,Saravanan Arumugam Seetharaman 한국유통과학회 2015 유통과학연구 Vol.13 No.8

Purpose - Total Quality Management (TQM) has received significant attention and interest from a large number of organizations around the world in various industries. These organizations have tried to embody TQM concepts in areas such as engineering and product design, marketing, R&D, procurement, production, personnel, and product inspection. Research design, data, and methodology - This study presents an overview of the fundamentals of TQM and an in depth review of the obstacles to the successful implementation of TQM. Results - In order to control the cost of manufacturing, the tracking of the cost of quality (COQ) allows companies to capture the actual overall cost incurred in producing a unit of product or service. The study explores the reasons why companies track the COQ and ways to address it. Conclusions – Based on the results, COQ is one of the key performance indicators for making more accurate strategic decisions as well as a critical aspect of TQM. The study also presents a few popular quality improvement tools that have been widely used in organizations successfully implementing TQM.

An environmentally benign one pot green synthesis of reduced graphene oxide based composites for the enzyme free electrochemical detection of hydrogen peroxide

Amala, G.,Saravanan, J.,JinYoo, D.,Kim, A.,Gnanakumar, G. Royal Society of Chemistry 2017 New journal of chemistry Vol.41 No.10

<P>A simple green protocol was developed for the simultaneous reduction of graphene oxide (GO) and metallic ions for the preparation of reduced GO/mono and bimetallic composites using Arachis hypogaea scrap extract. The highly crystalline and face-centered-cubic structures of monometallic silver (Ag) and bimetallic Ag-palladium (Ag-Pd) nanoparticles with the average particle size of 7 nm were effectively anchored over the rGO sheets. The spherical morphology, average particle size and structure of the monometallic Ag and bimetallic Ag-Pd nanoparticles anchored over the rGO sheets remained identical without the influence of any surfactants and passivating agents. The Fourier Transform Infrared spectra of prepared nanostructures elucidated the functional groups of Arachis hypogaea scrap responsible for the reduction of GO and metallic precursors. The supremacies of prepared nanostructures toward enzyme free hydrogen peroxide (H2O2) sensor performances were appraised under neutral conditions. The as-fabricated rGO/Ag-Pd/GCE responded linearly to the concentration of H2O2 over a wide range of 0.005 to 14.65 mM and exhibited a sensitivity of 342 mu A mM(-1) cm(-2) and a low level detection limit of 1.1 mu M toward H2O2 electrooxidation. Thus the proposed approach has not only provided conspicuous perceptions into the preparation of environmentally benign rGO based composites but has also tailored the expedients for new applications of green catalysts in enzyme free H2O2 sensors.</P>

ZnO nanoparticles with different concentrations inside organic solar cell active layer

Saravanan, Shanmugam,Ismail, Yasser A.M.,Silambarasan, Murugesan,Kishi, Naoki,Soga, Tetsuo Techno-Press 2016 Advances in energy research Vol.4 No.4

In the present work, ZnO nanoparticles (NPs) have been dispersed alone in the same solvent of the active layer for improving performance parameters of the organic solar cells. Different concentrations of the ZnO NPs have been blended inside active layer of the solar cell based on poly(3-hexylthiophene) (P3HT), which forms the hole-transport network, and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), which forms the electron-transport network. In the present investigations, the ZnO NPs may represent an efficient tool for improving light harvesting through light scattering inside active layer, electron mobility, and electron acceptance strength which tend to improve photocurrent and performance parameters of the investigated solar cell. The fill factor (FF) of the ZnO-doped solar cell increases nearly 14% compared to the non-doped solar cell when the doping is 50%. The present investigations show that ZnO NPs improve power conversion efficiency of the solar cell from 1.23% to 1.64% with increment around 25% that takes place after incorporation of 40% as a volume ratio of the ZnO NPs inside P3HT:PCBM active layer.

In-situ growth of 3D Cu-MOF on 1D halloysite nanotubes/reduced graphene oxide nanocomposite for simultaneous sensing of dopamine and paracetamol

Devaraj Manoj,Saravanan Rajendran,Tuan K.A. Hoang,Sabah Ansar,주상우,Yasser Vasseghian,Matias Soto-Moscoso 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.112 No.-

Three-dimensional (3D) metal–organic frameworks (MOFs) a class of porous materials with tunablestructure and surface functionality has arisen as electrode materials especially, for electrochemical sensingof analytes. However, MOFs possess intrinsic drawbacks such as poor conductivity with an agglomerationof particles, which restricted the electrochemical signal response in terms of sensitivity anddetection limits. In this regard, the present work aims to develop conducting Cu-MOF on HNTs, a goodsubstate for in-situ growth of MOF nanostructures due to the existence of abundant negatively chargedSi-OH that can help the growth of nanosized MOFs. The negatively charged siloxane (Si-O-Si) groupson the surface of HNTs can be attracted by positive charged Cu2+ ions present in the reaction mixturethrough strong electrostatic attraction. When subjected to hydrothermal treatment, the Cu2+ ions canform nano-sized Cu-MOF particles with assistance from 2-methylimidazole. Moreover, the presence ofgraphene oxide (GO) can improve the electrical conductivity, large surface area, and thus resulting inthe formation of conducting Cu-MOF/HNTs/rGO nanocomposite. Owing to the synergetic desirable propertiesof active metal sites and high porosity offered by Cu-MOF, the high conductivity of rGO, and thelarge surface area of HNTs, the resultant Cu-MOF/HNTs/rGO modified GC electrode demonstrates superiorelectrochemical signal response towards dopamine and paracetamol. Moreover, the developed sensorexhibits wide linear ranges of 0.1 lM–130 lM and 0.5–250 lM, with a low detection limit of 0.03 lMand 0.15 lM for dopamine and paracetamol, respectively.