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Oscillatory-plus-Transient Signal Decomposition Using TQWT and MCA

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Journal of Electronic Science and Technology 2019年第2期17卷 135-151页

作者： g. Ravi Shankar reddy Rameshwar Rao Department of Electronics and Communication Engineering CVR College of Engineering Hyderabad 500029 India Jawaharlal Nehru Technological University Hyderabad Hyderabad 500029 India

This paper describes a method for decomposing a signal into the sum of an oscillatory component and a transient component. The process uses the tunable Q-factor wavelet transform (TQWT): The oscillatory component is modeled as a signal that can be sparsely denoted by high Q-factor TQWT;similarly, the transient component is modeled as a piecewise smooth signal that can be sparsely denoted using low Q-factor TQWT. Since the low and high Q-factor TQWT has low coherence, the morphological component analysis (MCA) can effectively decompose the signal into oscillatory and transient components. The corresponding optimization problem of MCA is resolved by the split augmented Lagrangian shrinkage algorithm (SALSA). The applications of the proposed method to speech, electroencephalo-graph (EEg), and electrocardiograph (ECg) signals are included.

关键词： Morphological component analysis (MCA) oscillatory component split augmented Lagrangian shrinkage algorithm (SALSA) transient component tunable Q-factor wavelet transform (TQWT)

Effect of Hardfaced Interlayer Thickness and Low Hydrogen Ferritic Capping on Ballistic performance of Shielded Metal Arc Welded Armour Steel Joints

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Journal of Iron and Steel Research International 2013年第12期20卷 82-91页

作者： M Balakrishnan V Balasubramanian g Madhusudhan reddy Center for Materials Joining and Research(CEMAJOR) Department of Manufacturing EngineeringAnnamalai University Solidification Technology Division Metal Joining GroupDefense Metallurgical Research Laboratory(DMRL)

Armour grade quenched and tempered steel closely confirming to AISI 4340 is well known for its superior ballistic performance and hence used in the fabrication of combat vehicles. The traditional fillers like austenitic stain- less steel showed poor ballistic performance of these welded joints as compared to the base metal. Attempts have been made to deposit hardfaced interlayer between austenitic stainless steel weld metals. Though this method, mar-- ginal improvements in ballistic performance can be yielded, and cracks were observed in between base metal and hardfaced layer. Thickness of the hardfaced interlayer plays a vital role for the effective ballistic performance. Thus, an attempt has been made to investigate the effect of hardfaced interlayer thickness on ballistic performance of ar- mour steel welds. The results of effect of buttering, low hydrogen ferritic （LHF） filler and three different hardfaced layer thicknesses （4, 5.5 and 7 ram） on ballistid performance of shielded metal arc welded armour steel joints were given.

关键词： armour steel low hydrogen ferritic electrode sandwich structure ballistic performance hardfacing metallography

Experimental Investigation on the performance of Armour grade Q&T Steel Joints Fabricated by Flux Cored Arc Welding with Low Hydrogen Ferritic Consumables

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Journal of Materials Science & Technology 2009年第5期25卷 583-591页

作者： g.Magudeeswaran V.Balasubramanian g.Madhusudhan reddy g.g.p.lakrishnan Metal Joining Research Center(MJRC) Sri Ramakrishna Engineering CollegeN.G.G.O Colony-Post Centre for Materials Joining&Research(CEMAJOR) Department of Manufacturing EngineeringAnnamalai University Scientist-F Metal Joining SectionDefence Metallurgical Research Laboratory(DMRL)Kanchanbagh(P.O)

Quenched and Tempered （Q＆T） steels are widely used in the construction of military vehicles due to its high strength to weight ratio and high hardness. These steels are prone to hydrogen induced cracking （HIC） and softening in the heat affected zone （HAZ） after welding. The use of austenitic stainless steel （ASS） consumables to weld the above steel was the only available remedy to avoid HIC because of higher solubility for hydrogen in austenitic phase. Recent studies revealed that low hydrogen ferritic （LHF） steel consumables can also be used to weld Q＆T steels, which can give very low hydrogen levels in the weld deposits and required resistance against cold cracking. Hence, in this investigation an attempt has been made to study the performance of armour grade Q＆T steel joints fabricated by flux cored arc welding with LHF steel consumables. Two different consumables namely （i） austenitic stainless steel and （ii） low hydrogen ferritic steel have been used to fabricate the joints by flux cored arc welding （FCAW） process. The joints fabricated by LHF consumable exhibited superior transverse tensile properties due to the presence of ferrite microstructure in weld metal. The joints fabricated by ASS consumable showed higher impact toughness due to the presence of austenitic phase in weld metal microstructure. The HAZ softening in coarse grain heat affected zone （CgHAZ） is less in the joints fabricated using LHF consumable due to the lower heat input involved during fabrication compared to the joints fabricated using ASS consumables.

关键词： Quenched and tempered steel Flux cored arc welding.p.ocess Low hydrogen ferritic steel Tensile properties

Thermal radiation effect on unsteady threedimensional MHD flow of micropolar fluid over a horizontal surface of a parabola of revolution

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propulsion and power Research 2022年第1期11卷 129-142页

作者： S.R.R.reddy p.Bala Anki reddy Center for Nonlinear Systems Chennai Institute of TechnologyChennai600069T.N.India Department of Mathematics S.A.S.Vellore Institute of TechnologyVellore632014T.N.India

This paper explores the time-dependent magnetohydrodynamics(MHD)micropolar fluid flow over a three-dimensional variable stretching surface in the occurrence of radiation *** model time-dependent partial differential equations(pDE’s)in three independent variables are transformed into ordinary differential equations(ODE’s)by the suitable selfsimilarity *** perturbation method(HpM)and Runge-Kutta(RK)4^(th) order method along with shooting technique are used in the present *** also,HpM results are compared with Runge-Kutta(RK)4^(th) order method along with the shooting *** velocity,micro rotation in x and y directions,temperature,skin friction factor and heat transfer rates are examined for the emerging *** velocity profiles and momentum boundary layer thickness intensification with increasing values of the vortex viscosity *** higher value of a magnetic parameter declines the skin friction *** type of investigation may be profitable to the polymer fluids,exotic lubricants,electronic chips,artificial fibers,drawing of copper wires,etc.

关键词： Radiation parameter Magnetohydrodynamics Micropolar fluid Variable thickness sheet Homotopy perturbation method(HpM)

The myth of “minima” and “maxima”,the species of physalis in the Indian Subcontinent

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植物分类学报 2007年第2期45卷 239-245页

作者： Vatsavaya S RAJU C S reddy K g RAJARAO Department of Botany Kakatiya UniversityWarangal 506009 India Forestry & Ecology Division National Remote Sensing AgencyHyderabad 500008 India Department of Botany Andhra UniversityWaltair 530003 India

The status of the names, physalis minima L. and p. maxima Mill. (Solanaceae), and their alleged presence on the Indian subcontinent are discussed. The issues of nativity and identity of Linnaean physalis minima are long-debated while the use of the name p. maxima Mill. and its report from India are recent. The available evidence indicates that the name "p. minima L." is misapplied to two different elements, viz., p. angulata L. and p. lagascae Roem. & Schult. The name physalis minima L. may be rejected as nomen confusum, for which the paper provides the primary information. As on today, it is submerged under the synonymy of p. angulata L. The correct name for the widely known p. minima is p. lagascae. The name "p. maxima Mill." applied to the escape and naturalized weed in the Indian subcontinent and elsewhere is to be substituted by p. pruinosa L., a name misapplied to p. grisea (Waterf.) M. Martínez.

关键词：酸浆属植物酸浆值植物分类植物命名

Electro-magneto-hydrodynamic flow of couple stress nanofluids in micro-peristaltic channel with slip and convective conditions

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Applied Mathematics and Mechanics(English Edition) 2021年第4期42卷 593-606页

作者： K.RAMESH M.g.reddy B.SOUAYEH Department of Mathematics Symbiosis Institute of TechnologySymbiosis International(Deemed University)Pune 412115India Department of Mathematics Acharya Nagarjuna UniversityOngole CampusOngole 523001India Department of physics College of ScienceKing Faisal UniversityAl-Ahsa 31982Saudi Arabia Laboratory of Fluid Mechanics Physics DepartmentFaculty of Sciences of TunisUniversity of Tunis El ManarTunis 2092Tunisia

This study explores the effects of electro-magneto-hydrodynamics,Hall currents,and convective and slip boundary conditions on the peristaltic propulsion of nanofluids(considered as couple stress nanofluids)through porous symmetric *** phenomena of energy and mass transfer are considered under thermal radiation and heat source/*** governing equations are modeled and non-dimensionalized under appropriate dimensionless *** resulting system is solved numerically with MATHEMATICA(with an in-built function,namely the Runge-Kutta scheme).graphical results are presented for various fluid flow quantities,such as the velocity,the nanoparticle temperature,the nanoparticle concentration,the skin friction,the nanoparticle heat transfer coefficient,the nanoparticle concentration coefficient,and the trapping *** results indicate that the nanoparticle heat transfer coefficient is enhanced for the larger values of thermophoresis ***,an intriguing.p.enomenon is observed in trapping:the trapped bolus is expanded with an increase in the Hartmann ***,the bolus size decreases with the increasing values of both the Darcy number and the electroosmotic parameter.

关键词： peristalsis magnetohydrodynamics(MHD) nanofluid Hall current porous medium thermal radiation

Xenoesterogens and male infertility:myth or reality?

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Asian Journal of Andrology 2000年第4期2卷 263-269页

作者： Roya Rozati p.p.reddy p.Reddanna Rubina Mujtaba Assisted Conception Services Unit Mahavir Hospital and Research Centre Hyderabad(A. P.) 500 028 IndiaInstitute of Genetics and Hospital for Genetic Diseases Hyderabad IndiaDepartment of Animal Sciences School of Life Sciences University of Hyderabad IndiaAssisted Conception Services Unit Mahavir Hospital and Research Centre Hyderabad(A. P.) 500 028 India

Aim: To evaluate the role of polychlorinated biphenyls (pCBs) as a potential environmental hazard in the deteriora-tion of male fertility. Methods: Fifty-three males were studied. After a thorough case history evaluation and rele-vant clinical and laboratory investigations, pCBs were estimated in the seminal plasma of 21 infertile men with 'Unex-plained Male Factor' and 32 fertile controls. peak retention times of the eluants were compared with those of the com-mercially available standard pCB Mix, and the results confirmed spectrophotometrically. Seminal pCB concentrafonswere compared between i) fertile and infertile men and ii) men from different areas and diets. The relationship betweenpCB concentrations and measures of sperm quality such as the total motile sperm count, was assessed. Results:pCBs were detected in seminal plasma of infertile men but absent from controls. Sperm quantity and quality were sig-nificantly lower in infertile men compared to controls. The highest average pCB concentrations were found in fish-eat-ing urban dwellers, and followed in succession by fish-eating rural dwellers, non fish-eating urban dwellers and nonfish-eating mral dwellers. The total motile sperm counts were inversely proportional to the pCB concentrations and weresignificantly lower than those of the respective controls. Conclusion: pCBs may be instrumental in the deteriorationof sperm quantity and quality, a contaminated fish diet being the main source of exposure.(Asian J Androl 2000 Dec; 2: 263-269 )

关键词： polychlorinated biphenyls xenoestrogens male infertility sperm

Development of cost effective personnel armour through structural hybridization

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Defence Technology（防务技术） 2020年第6期16卷 1089-1097页

作者： p.Rama Subba reddy T.Sreekantha reddy I.Srikanth Juhi Kushwaha V.Madhu Defence Metallurgical Research Laboratory Hyderabad500058India Advanced Systems Laboratory Hyderabad500058India

The objective of the present study is to develop cost effective thermoplastic hybrid laminate using Dyneema®HB50 and Tensylon®HSBD 30A through structural hybridization *** having 20 mm thickness were fabricated and subjected to 7.6239 mm mild steel core projectile with an impact velocity of 730±10 ms*** such as energy absorption,back face deformation and rate of back face deformation were measured as a function of hybridization *** was observed that hybrid laminate with 50:50 ratio(w/w)of Tensylon®and Dyneema®with Tensylon®as front face showed 200%more energy absorption when compared to 100%Tensylon®laminate and showed equal energy absorption as that of expensive 100%Dyneema®***,hybrid laminate with TD50:50 ratio showed 40%lower in terms of final back face deformation than Dyneema®*** of back face deformation was also found to be slow for hybrid laminate as compared to Dyneema®*** mechanical analysis showed that,Tensylon®laminate has got higher stiffness and lower damping factor than Dyneema®and hybrid *** interface between Tensylon®and Dyneema®layers was found to be separating during the penetration process due to the poor interfacial *** behaviour of laminates for different hybridization ratios were studied by sectioning the impacted *** was observed that,the Tensylon®laminate has undergone shear cutting of fibers as major failure mode whereas the hybrid laminate showed shear cutting followed by tensile stretching,fiber pull out and *** inputs are highly useful for body armour applications to design cost effective armour with enhanced performance.

关键词： Dyneema® Tensylon® Hybrid laminate Ballistic impact Energy absorption Back face signature

Metallurgical characteristics of armour steel welded joints used for combat vehicle construction

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Defence Technology（防务技术） 2018年第5期14卷 590-606页

作者： g.Magudeeswaran V.Balasubramanian g.Madhusudan reddy Department of Mechanical Engineering PSNA College of Engineering and TechnologyKothandaraman NagarMuthanampatti624 622DindigulTamilnaduIndia Centre for Materials Joining&Research Department of Manufacturing EngineeringAnnamalai UniversityAnnamalai Nagar608002Tamil NaduIndia Outstanding Scientist & Associate Director Defence Metallurgical Research LaboratoryKanchanbaghHyderabad500058TelanganaIndia

Austenitic stainless steel(ASS) and High nickel steel(HNS) welding consumables are being used for welding Q&T steels, as they have higher solubility for hydrogen in austenitic phase, to avoid hydrogen induced cracking(HIC) but they are very expensive. In recent years, the developments of low hydrogen ferritic steel(LHF) consumables that contain no hygroscopic compounds are utilized for welding Q&T steels. Heat affected zone(HAZ) softening is another critical issue during welding of armour grade Q&T steels and it depends on the welding.p.ocess employed and the weld thermal cycle. In this investigation an attempt has been made to study the influence of welding consumables and welding.p.ocesses on metallurgical characteristics of armour grade Q&T steel joints by various metallurgical characterization procedures. Shielded metal arc welding(SMAW) and flux cored arc welding(FCAW) processes were used for making welds using ASS, LHF and HNS welding consumables. The joints fabricated by using LHF consumables offered lower degree of HAZ softening and there is no evidence of HIC in the joints fabricated using LHF consumables.

关键词： Armour grade Q&T steel Heat affected zone softening Shielded metal arc welding process Flux cored arc welding process Austenitic stainless steel Low hydrogen ferritic steel High nickel steel