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Friction 2021年第6期9卷 1749-1765页

作者： k.E.ch.ViDYASAGAR R.k.PANDEY Dinesh kALYANASUNDARAM Center for Biomedical Engineering Indian Institute of Technology DelhiNew Delhi 110016India Department of Biomedical Engineering College of EngineeringOsmania UniversityTelangana 500007India Department of Mechanical Engineering Indian Institute of Technology DelhiNew Delhi 110016India Department of Biomedical Engineering Indian Institute of Technology DelhiNew Delhi 110016India

in case of lightly loaded radial ball bearings,failure mechanisms other than fatigue such as smearing of raceways due to increased frictional torque and vibrations often ***,attempts have been made herein for reducing the frictional torque and minimizing the vibrations of a radial deep groove ball bearing employing surface textures at the inner *** pulsed laser was used to create texture(involving micro-dimples having different dimple area density)on the inner race of test *** an in-house developed test rig,frictional torque and vibrational parameters were measured at different speeds and light loads(*** vicinity of 0.01C,where C is dynamic load capacity of radial ball bearing).Significant reduction in frictional torque and overall vibrations were found in the presence of micro-dimples on inner race at light loads irrespective of operating *** without satisfying the minimum load needed criteria for the satisfactory operation,substantial reduction in smearing marks was found on the races of textured ball bearings in comparison to conventional cases.

关键词： ball bearing textured inner race grease lubricated frictional torque vibration

improvement of Deep Groove Ball Bearing’s Performance Using a Bionic Textured inner Race

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Journal of Bionic Engineering 2021年第4期18卷 974-990页

作者： k.E.ch.Vidyasagar R.k.Pandey Dinesh kalyanasundaram Center for Biomedical Engineering Indian Institute of Technology DelhiNew Delhi110016India Department of Biomedical Engineering College of EngineeringOsmania UniversityHyderabad500007India Department of Mechanical Engineering Indian Institute of Technology DelhiNew Delhi110016India Department of Biomedical Engineering All India Institute of Medical SciencesNew Delhi110029India

Micro-textured surfaces have improved the tribological performance of contact surfaces under lubricated conditions;however,not practiced due to manufacturing *** addition to simpler micro-pits or straight-trench type textures,sophisticated bioinspired textures on commercial radial ball bearings have been scarcely *** this work,Dendroaspis polylepis(Mamba snake)skin-type textures were fabricated on the inner race of FAG radial ball bearings using a nanosecond fiber laser *** the snake textures were primarily meant to enhance friction,the dimensions of the texture have been carefully chosen to improve the tribological performance under lubricated *** textured bearings were assembled and experimented at various rotational speeds and lightly loaded conditions to measure vibrational amplitude,frictional torque,and temperature *** to untextured(conventional)bearing,the snake-skin type textured bearings resulted in improved tribo-dynamic performance.

关键词： bionic texture radial ball bearing frictional torque vibration temperature

SEQUENTiAL CONVEX PROGRAMMiNG METHODS FOR SOLViNG LARGE TOPOLOGY OPTiMiZATiON PROBLEMS： iMPLEMENTATiON AND COMPUTATiONAL RESULTS

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Journal of Computational Mathematics 2005年第5期23卷 491-502页

作者： Qin Ni ch.Zillober k.Schittkowski Nanjing University of Aeronautics and Astronautics 210016 Nanjing China Department of Computer Science University of BayreuthD-95440 BayreuthGermany

in this paper, we describe a method to solve large-scale structural optimization problems by sequential convex programming （SCP）. A predictor-corrector interior point method is applied to solve the strictly convex subproblems. The SCP algorithm and the topology optimization approach are introduced. Especially, different strategies to solve certain linear systems of equations are analyzed. Numerical results are presented to show the efficiency of the proposed method for solving topology optimization problems and to compare different variants.

关键词： Large scale optimization Topology optimization Sequential convex programming method Predictor-corrector interior point method Method of moving asymptotes

Contrasting plant growth performance of invasive polyploid and native diploid Prosopis is mediated by the soil bacterial community

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Ecological Processes 2023年第1期12卷 193-203页

作者： Rishabh kaushik Meesha Sharma ch.V.Ramana ch.Sasikala Maharaj k.Pandit Jealott’s Hill international Research Centre WarfieldBracknell RG426EYEnglandUK Department of Environmental Studies University of DelhiDelhi 110007India Department of Plant Sciences School of Life SciencesUniversity of HyderabadP.O.Central UniversityHyderabad 500046India Bacterial Discovery Laboratory Centre for EnvironmentInstitute of Science and TechnologyJ.N.T.University HyderabadKukatpallyHyderabad 500085India Jindal School of Environment&Sustainability OP Jindal Global UniversitySonipatHaryana 131001India

Background Soil microbial communities affect above-ground plant diversity and community composition by influencing plant growth *** studies have tested the effect of soil bacterial microbiome on growth performance of native and invasive plants,but the influence of specific bacterial isolates has not been ***,we investigated the effects of soil bacterial exclusion by soil sterilization and by inoculation of Streptomyces rhizobacterial isolates on the growth performance of native and invasive Prosopis *** Plant growth performance of invasive *** was significantly reduced when grown in sterilized soils,whereas native *** showed enhanced growth performance in the sterilized *** grown in the soil inoculated with the specific Streptomyces isolate from ***(PJ1),the growth performance of invasive *** was significantly enhanced while that of native *** seedlings was significantly ***,inoculation of *** and *** seedlings with Streptomyces isolate from the rhizosphere of native ***(PC1)had no significant effect on the growth performances either of *** or *** Our study reveals that invasive *** experiences positive feedback from the non-native soil bacterial community,while the native *** experiences negative feedback from its soil bacterial *** results provide fresh experimental evidence for the enemy release hypothesis,and further our understanding of the contrasting growth-promoting effects of differentially recruited microbial species belonging to the same genus(Streptomyces)in the rhizospheres of alien invasive and native plants.

关键词： Soil bacteria Streptomyces invasive Prosopis juliflora Prosopis cineraria Soil microbiota

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Photoproduction of the Θ^+ and its vector andaxial-vector structure

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chinese Physics C 2009年第12期33卷 1279-1284页

作者： H.-ch. kim k. Goeke T. Ledwig S. i. Nam Department of Physics Inha University Incheon 402-751 Republic of Korea institut fr Theoretische Physik ii Ruhr-Universitt Bochum D-44780 Bochum Germany institut fr kernphysik Universitt Mainz D-55099 Mainz Germany Department of Physics Chung-Yuan Christian University (CYCU)

We present recent investigations on the vector and axial-vector transitions of the baryon antidecuplet within the framework of the self-consistent SU（3） chiral quark-soliton model, taking into account the 1/No rotational and linear mscorrections. The main contribution to the electric-like transition form factor comes from the wave-function corrections. This is a consequence of the generalized Ademollo-Gatto theorem. it is also found that in general the leading-order contributions are almost canceled by the rotational 1/No corrections. The results are summarized as follows： the vector and tensor k＇NO coupling constants, gk＊N= 0.74--0.87 and fk＊N =0.53--1.16, respectively, and F→kN = 0.71 MeV, based on the result of the kN coupling constant gkne =0.83. We also show the differential cross sections and beam asymmetries, based on the present results. We also discuss the connection of present results with the original work by Diakonov, Petrov, and Polyakov.

关键词： Baryon antidecuplet vector and axial-vector transition form factors chiral quark-soliton model,Photoproduction of the +

Adaptive Signal Enhancement Unit for EEG Analysis in Remote Patient Care Monitoring Systems

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Computers, Materials & Continua 2021年第5期67卷 1801-1817页

作者： ch.Srinivas k.chandrabhushana Rao Department of Electronics and Communication Engineering J.N.T.UniversityKakinada533003India Department of Electronics and Communication Engineering JNTUK-UCEVVizianagaram535003India

in this paper we propose an efcient process of physiological artifact elimination methodology from brain waves(BW),which are also commonly known as electroencephalogram(EEG)*** a clinical environment during the acquisition of BW several artifacts contaminates the actual BW *** leads to inaccurate and ambiguous *** the statistical nature of the EEG signal is more non-stationery,adaptive ltering is the more promising method for the process of artifact *** clinical conditions,the conventional adaptive tech.iques require many numbers of computational operations and leads to data samples overlapping and instability of the algorithm *** causes delay in diagnosis and decision *** overcome this problem in our work we propose to set a threshold value to diminish the problem of round off *** resultant adaptive algorithm based on this strategy is Non-linear Least mean square(NL2MS)***,to improve this algorithm in terms of ltering capability we perform data normalization,using this algorithm several hybrid versions are developed to improve ltering and reduce computational *** the method,a new signal enhancement unit(SEU)is realized and performance of various hybrid versions of algorithms examined using real EEG signals recorded from the *** ability of the proposed schemes is measured in terms of convergence,enhancement and multiplications *** various SEUs,the MCN2L 2MS algorithm achieves 14.6734,12.8732,10.9257,15.7790 dB during the artifact removal of RA,EMG,CSA and EBA components with only two ***,this algorithm seems to be better candidate for artifact elimination.

关键词： Adaptive algorithms artifacts brain waves clipped algorithms signal enhancement unit wireless EEG monitoring

Spectroscopic and fluorescence properties of Sm^(3+)-doped zincfluorophosphate glasses

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Journal of Rare Earths 2014年第10期32卷 918-926页

作者： V.B.Sreedhar ch.Basavapoornima C.k.Jayasankar Department of Physics Sri Venkateswara University Department of Physics National Degree and P.G. College

Optical absorption and fluorescence spectra of Sm3＋-doped zincfluorophosphate glasses with molar composition of 44P2O5＋17k20＋9Al2O3＋（30-χ）ZnF2＋χSm2O3 （χ=0.01 mol.%, 0.05 mol.%, 0.1 mol.%, 0.5 mol.%, 1.0 mol.%, 2.0 and 3.0 mol.%） referred as PkAZFSm were prepared by melt quenching tech.ique and were characterized through Raman, absorption, emission and decay curve analysis. From the absorption spectra, Judd-Ofelt intensity parameters were determined and were used to predict radiative properties such as transition probabilities （AR, radiative lifetimes （τR）, branching ratios （βR）, effective bandwidths （△λeff） and stimulated emission cross-section （σ（λp）） for the excited 4G5/2 luminescent level. The decay curve for the 4G5/2 level was single exponential for lower concentration and became non-exponential for higher concentrations. The non-exponential nature of the decay curves of the 4G5/2 level increased with increase in Sm3＋ ions concentration accompanied by decrease in lifetime due to energy transfer processes among the Sm3＋ ions. The non-exponential decay curves was well fitted to the generalized inokuti-Hirayama model for S=6, indicating that the energy transfer among optically active ions was of dipole-dipole interaction. The cross-relaxation mechanism responsible for the quenching of lifetimes and the effect of variation of concentration on the spectroscopic properties were also discussed.

关键词： zincfluorophosphate glasses samarium Raman spectrum optical properties fluorescence properties rare earths

An improved peak side lobe reduction method for linear array antenna for military applications

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international Journal of intelligent Computing and Cybernetics 2021年第2期14卷 185-197页

作者： Ravi Tej D Sri kavya ch k Sarat k.kotamraju Department of Electronics and Communication Engineering Koneru Lakshmaiah Education FoundationGunturIndia

Purpose-The purpose of this paper is to improve energy efficiency and further reduction of side lobe level the algorithm proposed is firework *** this paper,roused by the eminent swarm conduct of firecrackers,a novel multitude insight calculation called fireworks algorithm(FA)is proposed for work *** FA is introduced and actualized by mimicking the blast procedure of *** the FA,two blast(search)forms are utilized and systems for keeping decent variety of sparkles are likewise all around *** approve the presentation of the proposed FA,correlation tests were led on nine benchmark test capacities among the FA,the standard PSO(SPSO)and the clonal PSO(CPSO).Design/methodology/approach-The antenna arrays are used to improve the capacity and spectral efficiency of wireless communication *** latest communication systems use the antenna array technology to improve the spectral efficiency,fill rate and the energy efficiency of the communication system can be *** of the most important properties of antenna array is beam pattern.A directional main lobe with low side lobe level(SLL)of the beam pattern will reduce the interference and enhance the quality of *** classical methods for reducing the side lobe level are differential evolution algorithm and PSO *** this paper,roused by the eminent swarm conduct of firecrackers,a novel multitude insight calculation called fireworks algorithm(FA)is proposed for work *** FA is introduced and actualized by mimicking the blast procedure of *** the FA,two blast(search)forms are utilized and systems for keeping decent variety of sparkles are likewise all around *** approve the presentation of the proposed FA,correlation tests were led on nine benchmark test capacities among the FA,the standard PSO(SPSO)and the clonal PSO(CPSO).it is demonstrated that the FA plainly beats the SPSO and the CPSO in both enhancement exactness and combinat

关键词： Antenna arrays Spectral efficiency Fill rate interference Evolution algorithm Side lobe level Paper type Research paper

Exploring COViD-19 from the perspectives of healthcare personnel in Malawi

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Health Care Science

Health Care Science 2023年第4期2卷 242-254页

作者： chúk Odenigbo Eric Crighton Department of Geography Environment and Geomatics at the University of Ottawa60 UniversityOttawaOntarioCanada

Background:The Coronavirus 2019 disease(COViD-19)brought many healthcare systems around the world to the point of collapse all the while putting the lives of healthcare workers at *** study forgoes an institutional look at healthcare to center individual healthcare personnel in Malawi to better understand(1)how the worldviews of healthcare workers impact their work in the context of COViD-19,(2)how COViD-19 impacted healthcare workers,and(3)the unique conditions faced by being a healthcare worker in a low-income ***:This research uses a hermeneutic phenomenological approach to qualitative methodology involving in-depth interviews(n=15)with health-care workers,traditional healers,and hospital *** data collected were inductively coded and analyzed using the framework method,producing rich descriptions on how COViD-19 impacted the lifeworlds of healthcare workers in ***:The findings reveal many of the struggles healthcare workers faced due to misaligned government policy and perceived proximity to COViD-19;outline their needs such as wanting better resources,funds,wages,and public health communication;and,exemplify the significant role that personal biases,worldviews,and sense of fear played in how healthcare workers perceived and interacted with ***:Much of what was said echoes beyond borders,reflecting common global sentiments felt by healthcare personnel,and offers directions to explore building policies,strategies,and plans in preparation for any future disease outbreaks.

关键词： COViD-19 pandemic healthcare workers fear Malawi discrimination violence

The Structure of Cool Flame Fronts of Pentane, iso-Pentane and Their Mixture

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Journal of Thermal Science 2000年第4期9卷 365-370页

作者： Z.A.Mansurov ch.k.Westbrook 等 Al－FarabikazakhStateNationalUniversity KarasaiBatryStr.95Akmaty480012kazakhstan UniversityofCaliforniaLawrenceLivermoreNationalLaboratory

An experimental study of the combustion of two isomers of n-pentane and iso-pentane in laminar cool flames has been carried out. Three flames were studied, one with n-pentane, the second with iso-pentane, and the third with an equimolar mixture of the two isomers. Particular attention has been given to the low temperature region ahead of the hot region of the flame and the cool flame chemistry occurring there. A unique experimental facility has been used to provide access to this cool flame region. Comparisons are made of the structures of the three flames, with particular attention on the different intermediate species produced and the correlations between the fuel molecule structure and the specific intermediates produced.

关键词： hydrocarbon cool names concentration profile.