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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

An exploration of frictional and vibrational behaviors of textured deep groove ball bearing in the vicinity of requisite minimum load

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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

Prevalence of transfusion transmissible infections among various donor groups:A comparative analysis

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World Journal of Virology 2025年第1期14卷 108-117页

作者： Sanjay K Thakur Anil K Sinha Santosh K Sharma Aarzoo Jahan dinesh K Negi Ruchika Gupta Sompal Singh Regional Blood Transfusion Centre Hindu Rao Hospital and NDMC Medical CollegeNorth Delhi 110007DelhiIndia Department of Zoology Veer Kunwar Singh UniversityAra 802301BiharIndia Regional Blood Transfusion Centre and Pathology Hindu Rao Hospital and NDMC Medical CollegeNorth Delhi 110007DelhiIndia Department of Cytopathology ICMR-National Institute of Cancer Prevention and ResearchNoida 201301Uttar PradeshIndia

BACKGROUND Transfusion transmissible infections(TTIs)are illnesses spread through contaminated blood or blood *** India,screening for TTIs such as hepatitis B virus(HBV),hepatitis C virus(HCV),human immunodeficiency virus(HIV)-I/II,malaria,and syphilis is mandatory before blood ***,HCV,HBV,and HIV are the leading viruses causing mortality,affecting millions of people globally,including those with co-infections of HIV/HCV and HIV/*** highlight the impact of TTIs on life expectancy and health risks,such as liver cirrhosis,cancer,and other diseases in individuals with chronic ***,millions of blood donations take place annually,emphasizing the importance of maintaining blood *** To study the prevalence of TTIs,viz.,HBV,HCV,HIV I/II,syphilis,and malaria parasite(MP),among different blood donor *** The study assessed the prevalence of TTIs among different blood donor groups in Delhi,*** included total donors,in-house donors,total camp donors,institutional camp donors,and community camp *** for HIV,HBV,and HCV were done using enzyme-linked immunosorbent assay,while syphilis was tested with rapid plasma reagins and MP rapid card *** prevalence of HBV,HCV,HIV,and syphilis,expressed as *** in infection rates between the groups were analyzed usingχ²tests and P-values(less than 0.05).RESULTS The study evaluated TTIs among 42158 blood donors in *** overall cumulative frequency of TTIs in total blood donors was 2.071%,and the frequencies of HBV,HCV,HIV-I/II,venereal disease research laboratory,and MP were 1.048%,0.425%,0.221%,0.377%,and 0.0024%,***-house donors,representing 37656 donors,had the highest transfusion transmissible infection(TTI)prevalence at 2.167%.Among total camp donors(4502 donors),TTIs were identified in 1.266%of donors,while community camp donors(2439 donors)exhibited a prevalence of 1.558%.Institutional camp donors(2063 donors)had the l

关键词： Blood donors Transfusion transmissible infections Hepatitis B virus Human immunodeficiency virus Hepatitis C virus Malaria parasite Syphilis

Role of phonon drag and carrier diffusion in thermoelectric power of polycrystalline La_(0.97)Na_(0.03)MnO_(3)manganites

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Journal of Advanced Ceramics 2014年第3期3卷 224-229页

作者： dinesh VARSHNEY dinesh chOUDHARY Materials Science Laboratory School of PhysicsVigyan BhawanDevi Ahilya UniversityKhandwa Road CampusIndore 452001India

We develop a theoretical model for quantitative analysis of temperature-dependent thermoelectric power of monovalent(Na)doped La_(0.97)Na_(0.03)MnO_(3)*** the ferromagnetic regime,we have evaluated the phonon thermoelectric power by incorporating the scattering of phonons with impurities,grain boundaries,charge carriers and *** doing so,we use the Mott expression to compute the carrier(hole)diffusion thermoelectric power(S_(c)^(diff))using Fermi energy as carrier(hole)-free parameter,and S_(c)^(diff)shows linear temperature dependence and phonon drag S_(ph)^(drag)increases exponentially with temperature which is an artifact of various operating scattering *** is also shown that for phonons the scattering and transport cross-sections are proportional toω^(4)in the Rayleigh regime wherewis the frequency of the *** analysis of thermoelectric power from the present model shows similar results as those revealed from experiments.

关键词： phonon drag carrier diffusion thermoelectric power

Effect of Rare Earth and Transition Metal Elements on the Glass Forming Ability of Mechanical Alloyed Al–TM–RE Based Amorphous Alloys

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Journal of Materials Science & Technology 2015年第11期31卷 1118-1124页

作者： Ram S.maurya Tapas Laha Department of Metallurgical & Materials Engineering Indian Institute of Technology Kharagpur

The present work aims to compare the amorphous phase forming ability of ternary and quaternary Al based alloys （Al86Ni8Y6, Al86GNi6Y6Co2, Al86NigLa6 and Al86Ni8Y45La15） synthesized via mechanical alloying by varying the composition, i.e. fully or partially replacing rare earth （RE） and transition metal （TM） elements based on similar atomic radii and coordination number. X-ray diffraction and high resolution transmission electron microscopy study revealed that the amorphization process occurred through formation of various intermetallic phases and nanocrystalline FCC Al. Fully amorphous phase was obtained for the alloys not containing lanthanum, whereas the other alloys containing La showed partial amorphization with reappearance of intermetallic phases attributed to mechanical crystallization. Differential scanning calorimetry study confirmed better thermal stability with wider transformation temperature for the alloys without La.

关键词： Al-TM-RE amorphous alloy Mechanical alloying Glass forming ability Microstructural transformation Intermetallics Glass transition temperature

Varna-based optimization:a novel method for capacitated controller placement problem in SDN

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Frontiers of Computer Science 2020年第3期14卷 87-111页

作者： Ashutosh Kumar SINGH Saurabh maurya Shashank SRIVASTAVA Department of Computer Science&Engineering Motilal Nehru National Institute of Technology AllahabadAllahabad 211004U.P.India

Recently,software defined networking(SDN)is a promising paradigm shift that decouples the control plane from the data *** can centrally monitor and control the network through softwarization,i.e.,*** controllers are a necessity of current SDN based *** multiple controllers in an optimum way is known as controller placement problem(CPP).Earlier,solutions of CPP only concentrated on propagation latency but overlooked the capacity of controllers and the dynamic load on switches,which is a significant factor in real *** this paper,we develop a novel optimization algorithm named varna-based optimization(VBO)and use it to solve *** the best of our knowledge,this is the first attempt to minimize the total average latency of SDN along with the implementation of TLBO and Jaya algorithms to solve CPP for all twelve possible *** experimental results show that TLBO outperforms PSO,and VBO outperforms TLBO and Jaya algorithms in all scenarios for all topologies.

关键词： SDN controller placement CPP latency VBO

Experimental study of the restoring force mechanism in the self-centering beam （SCB）

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Frontiers of Structural and Civil Engineering 2016年第3期10卷 272-282页

作者： Abhilasha maurya Matthew R. EATHERTON Department of Civil and Environmental Engineering Virginia Tech Blacksburg VA 2406 USA

In the past, several self-centering （SC） seismic systems have been developed. However, examples of selfcentering systems used in practice are limited due to unusual field construction practices, high initial cost premiums and deformation incompatibility with the gravity framing. A self centering beam moment frame （SCB-MF） has been developed that mitigates several of these issues while adding to the advantages of a typical SC system. The self-centering beam （SCB） is a shop-fabricated, self-contained structural component that when implemented in a moment resisting frame can bring a building back to plumb after an earthquake. This paper describes the SCB concepts and experimental program on five SCB specimens at two-third scale relative to a prototype building. Experimental results are presented including the global force-deformation behavior. The SCBs are shown to undergo 5%-6% story drift without any observable damage to the SCB body and columns. Strength equations developed for the SCB predict the moment capacity well, with a mean difference of 6% between experimental and predicted capacities. The behavior of the restoring force mechanism is described. The limit states that cause a loss in system＇s restoring force which lead to a decrease in the selfcentering capacity of the SCB-MF, are presented.

关键词： self-centering seismic system seismic design hysteretic behavior restoring force resilient structural system

MicroRNA-99a mimics inhibit M1 macrophage phenotype and adipose tissue inflammation by targeting TNFα

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Cellular & Molecular Immunology 2019年第5期16卷 495-507页

作者： Anant Jaiswal Sukka Santosh Reddy Mohita maurya Preeti maurya Manoj Kumar Barthwal Division of Pharmacology Council of Scientific and Industrial Research-Central Drug Research Institute(CSIR-CDRI)Lucknow 226031 U.P.India Academy of Scientific and Innovative Research New Delhi 110025India

In human adipose tissue and obesity,miR-99a expression is negatively correlated with ***,the present study investigated the role of miR-99a in macrophage phenotype activation and adipose tissue inflammation.M2 BMDMs showed a significant increase in miR-99a expression when compared to the M0 and M1 ***-switching experiments established an association between upregulated miR-99a expression and the M2 *** of miR-99a prevented M1 phenotype activation and attenuated bactericidal ***,knockdown of miR-99a abolished M2 phenotype *** means of in silico target prediction tools and a luciferase reporter assay,TNFαwas identified as a direct target of *** of TNFαrecapitulated the effect of miR-99a overexpression in M1 *** a db/db mice model,miR-99a expression was reduced in eWAT and F4/80+*** overexpression of miR-99a in db/db mice attenuated adipocyte hypertrophy with increased CD301 and reduced CD86 *** cytometry analysis also showed an increased M2 and a reduced M1 macrophage *** of miR-99a also improved the diabetic dyslipidemia and insulin signaling in eWAT and liver,with an attenuated expression of gluconeogenesis and cholesterol metabolism genes in the ***,adoptive transfer of miR-99a-overexpressing macrophages in the db/db mice recapitulated in vivo miR-99a mimic effects with increased M2 and reduced M1 macrophage populations and improved systemic glucose,insulin sensitivity,and insulin signaling in the eWAT and *** present study demonstrates that miR-99a mimics can regulate macrophage M1 phenotype activation by targeting TNFα.miR-99a therapeutics in diabetic mice reduces the adipose tissue inflammation and improves insulin sensitivity.

关键词： inflammation macrophage CD86

Modified Sliding Mode Observer-based Direct Torque Control of Six-phase Asymmetric Induction Motor Drive

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chinese Journal of Electrical Engineering 2023年第3期9卷 111-123页

作者： Krunal Shah Abid Mansuri Rakesh maurya Department of Electrical Engineering Sardar Vallabhbhai National Institute of TechnologySurat 395007India

In this study,a six-phase induction asymmetric induction motor(SPAIM)was examined,whose performance surpasses that of its three-phase counterpart,with regard to the torque density,torque pulsation,fault tolerance,power rating per inverter lag,and noise ***-encoder-less direct torque control(DTC)for SPAIM with virtual voltage vectors(VVVs)and a modified sliding mode observer(MSMO)are *** SPAIM model was developed using a stationaryα-βframe for *** conventional DTC of the SPAIM drive is a simple extension of DTC for a 3-Φmotor drive that yields higher distortion in the stator *** mitigate the large amount of distortion in the stator current,VVVs were used to significantly reduce the harmonic content in the stator ***,to overcome the large amount of chattering observed in the case of a traditional sliding mode observer,particularly under low-speed operation,the MSMO was employed to reduce chattering even under low-speed *** performance of the proposed observer was verified under all the operating conditions suitable for the propulsion mode of an electric vehicle using Matlab/Simulink,and the results were experimentally validated.

关键词： Direct torque control multiphase induction motor drive sliding mode observer space vector modulation