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Controlling Tendons to Modulate Stiffness of a Planar-to-Spatial Tendon-Driven Continuum Manipulator Under External Uncertain Forces

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Journal of Bionic Engineering 2024年第2期21卷 821-841页

作者： vipin Pachouri Pushparaj Mani Pathak Indian Institute of Technology Roorkee Roorkee247667India

Continuum manipulators(CM)are soft and flexible manipulators with large numbers of degrees of freedom and can perform complex tasks in an unstructured ***,their deformability and compliance can deviate distal tip under uncertain external *** address this challenge,a novel tension-based control scheme has been proposed to modulate the stiffness of a tendon-driven CM,reducing the tip position errors caused by uncertain external *** minimize the tip position error,a virtual spring is positioned between the deviated and the desired tip *** proposed algorithm corrects the manipulator deviated tip position,improving tension distribution and stiffness profile,resulting in higher stiffness and better *** corresponding task space stiffness and condition numbers are also computed under different cases,indicating the effectiveness of the tension control scheme in modulating the manipulator's *** validation conducted on an in-house developed prototype confirms the practical feasibility of the proposed approach.

关键词： Continuum arm Hyper-redundant robots Variable stiffness manipulator Tension-based control Mechatronic systems

Development of metal organic fromwork-199 immobilized zeolite foam for adsorption of common indoor VOCs

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Journal of Environmental Sciences 2017年第5期29卷 321-330页

作者： vipin K.Saini Joao Pires School of Environment and Natural Resources Doon UniversityDehradun 248001India Department of Chemistry and Biochemistry Faculty of SciencesUniversity of LisbonLisbon 1749-016Portugal

Reticulated foam shaped adsorbents are more efficient for the removal of volatile organic compounds（VOCs）,particularly from low VOC-concentration indoor air streams. In this study composite structure of zeolite and metal organic frameworks（MOFs）,referred as ZMF,has been fabricated by immobilization of fine MOF-199 powder on foam shaped Zeolite Socony Mobil-5（ZSM-5）Zeolitic structure,referred as ZF. The ZMF possess a uniform and well-dispersed coating of MOF-199 on the porous framework of ZF. It shows higher surface area,pore volume,and VOCs adsorption capacity,as compared to ***-fabrication changes in selective adsorption properties of ZMF were studied with three common indoor VOCs（benzene,n-hexane,and cyclohexane）,using gravimetric adsorption technique. The adsorption capacity of ZMF with different VOCs follow the order of benzene 〉 n-hexane 〉 cyclohexane. In comparison with MOF-199 and ZF,the composite structure ZMF shows improvement in selectivity for benzene from other two VOCs. Further,improvement in efficiency and stability of prepared ZMF was found to be associated with its high MOF loading capacity and unique morphological and structural properties. The developed composite structure with improved VOCs removal and recyclability could be a promising material for small to limited scale air pollution treatment units.

关键词： VOCs Adsorption Composite materials Selectivity Zeolite foam MOFs HKUST-1

Specific Control of Immunity by Regulatory CD8 T Cells

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Cellular & Molecular Immunology 2005年第1期2卷 11-19页

作者： XiaOIeiTang TrevorRFSmitl vipin Kumar Laboratory of Autoimmunity Torrey Pines Institute for Molecular Studies San DiegoCA USA. Corresponding to:Dr.vipin Kumar Torrey Pines Institute for Molecular Studies3550 General Atomics CourtSan DiegoCA 92121

T lymphocytes with dedicated suppressor function(Treg)play a crucial role in the homeostatic control of immunity in the *** Treg phenotypes have now been identified in the CD4 and CD8 T cell populations, suggesting their down-regulatory function in both human and animal models of autoimmunity,transplantation and tumor *** we will focus on the CD8 Treg population and their ability to specifically inhibit a pathogenic autoimmune *** review will detail the current advances in the knowledge of CD8 Treg in the context of antigen specificity,phenotype,MHC restriction,mechanism of action,and *** & Molecular Immunology.2005;2(1):11-19.

关键词： regulatory T cell Qa-1 TCR-peptides apoptosis immune deviation cross-priming EAE

Influence of Sputtering Pressure on the Structure and Mechanical Properties of Nanocomposite Ti-Si-N Thin Films

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Journal of Materials Science & Technology 2010年第8期26卷 673-678页

作者： vipin Chawla R.Jayaganthan Ramesh Chandra Department of Metallurgical and Materials Engineering & Centre of Nanotechnology Indian Institute of Technology Roorkee Nano Science Laboratory Institute Instrumentation CentreIndian Institute of Technology Roorkee

Nanocomposite Ti-Si-N thin films have been deposited on Si （100） substrate by direct current/radio frequency （DC/RF） magnetron sputtering. The effect of varying deposition parameters on the structure and mechanical properties of Ti-Si-N films has been investigated by characterization techniques such as X-ray dif- fraction （XRD）, field emission scanning electron microscopy （FE-SEM）, atomic force microscopy （AFM） and nanoindentation, respectively. XRD analysis of the thin films exhibit all （111）, （200） and （220） peaks initially with varying sputtering pressure, but （111） peak dominates at higher sputtering pressure. The crystallite size calculated from XRD peaks shows that it increases with increasing sputtering pressure. Microstructural analy- sis reveals that the dense blurred grains transform into uniform grains in the films and shows porosity with increasing sputtering pressure. The surface roughness of the Ti-Si-N films increases with varying sputtering pressure. The hardness and Youngrs modulus values of Ti-Si-N films are 33.7 and 278.6 GPa, respectively, with 0.7 Pa sputtering pressure but it decreases with further increase in sputtering pressure due to an increase in porosity of the films.

关键词： Ti-Si-N films Nanoindentation Microstructural characterization

NKT cell subsets as key participants in liver physiology and pathology

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Cellular & Molecular Immunology 2016年第3期13卷 337-346页

作者： Keya Bandyopadhyay Idania Marrero vipin Kumar Department of Medicine University of California San Diego La Jolla CA 92037 USA

Natural killer T （NKT） cells are innate-like lymphocytes that generally recognize lipid antigens and are enriched in microvascular compartments of the liver. NKT cells can be activated by self- or microbial-lipid antigens and by signaling through toll-like receptors. Following activation, NKT cells rapidly secrete pro-inflammatory or anti- inflammatory cytokines and chemokines, and thereby determine the milieu for subsequent immunity or tolerance. It is becoming clear that two different subsets of NKT cells-type I and type II--have different modes of antigen recognition and have opposing roles in inflammatory liver diseases. Here we focus mainly on the roles of both NKT cell subsets in the maintenance of immune tolerance and inflammatory diseases in liver. Furthermore, how the differential activation of type I and type II NKT cells influences other innate cells and adaptive immune cells to result in important consequences for tissue integrity is discussed. It is crucial that better reagents, including CDld tetramers, be used in clinical studies to define the roles of NKT cells in liver diseases in patients.

关键词： CDld lipids liver disease NKT cells

Tribological characteristics of friction stir processed graphite and tin/LM24 surface composites

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Friction 2021年第3期9卷 569-582页

作者： vipin SHARMA Ujjwal PRAKASH B.Venkata MANOJ KUMAR Department of Metallurgical and Materials Engineering Indian Institute of Technology RoorkeeRoorkee 247667India

Friction stir processing(FSP)is an emerging solid-state technique for preparing surface composites using various *** and metallic particles are easily reinforced in a matrix by this *** composites made from an LM24 alloy reinforced with graphite and tin,with good wettability and material flow owing to the low melting point of tin,were fabricated by FSP at two rotational speeds of 1,400 and 1,000 *** its low hardness,the graphite/LM24 surface composite fabricated at a higher rotational speed of 1,400 rpm exhibited better wear ***,its frictional behavior was not significantly affected by the *** fabricated surface composites with graphite and tin reinforcement as well as graphite-only reinforcement exhibited contradicting behaviors under sliding wear *** post wear analysis indicated that abrasion,adhesion,layer formation,and delamination occurred on the composite surfaces.

关键词： composites friction stir processing graphite tin Al-Si alloy wear

Genetic differentiation between three ecological variants （‘type’, ＇mysorensis＇ and ‘intermediate’） of malaria vector Anopheles stephensi （Diptera： Culicidae）

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Insect Science 2010年第4期17卷 335-343页

作者： vipin Madhulika Dube S. K. Gakhar Advanced Centre for Biotechnology Department of Statistics Maharshi Dayanand University Rohtak India

Anopheles stephensi is the main vector of urban malaria in South Asia. Three ecological variants （‘type’, ‘mysorensis’ and ‘intermediate’） of An. stephensi have been reported on the basis of ecology and egg morphology. However, it is unclear if there is any genetic isolation between the three variants. We analyzed the three variants of An. stephensi using eight microsatellite loci and found that large and significant genetic differentiation exists between them （mean FST = 0.393 and mean RST = 0.422）. Pairwise estimates of genetic differentiation between the variants were ‘type’ versus ‘mysorensis’ （mean FsT = 0.411 and mean RST = 0.308）, ‘type’ versus‘intermediate’ （mean FsT = 0.388 and mean RST = 0.518） and ‘intermediate’versus ＇mysorensis＇（mean FST = 0.387 and mean RST = 0.398） and all were statistically significant （P 〈 0.05）. The greater sensitivity of RST in differentiation indicated that mutations and not genetic drift had generated the differences between three variants of An. stephensi. The present study indicated large genetic differentiation and presence of non-significant low level ofgene flow between the three variants （‘type’,‘ mysorensis’ and ‘intermediate’） of An. stephensi.

关键词： Anopheles stephensi ecological variants gene flow intermediate mysorensis type

Combined cold,heat and power(CCHP)systems and fuel cells for CCHP applications:a topological review

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Clean Energy 2023年第2期7卷 436-491页

作者： Nganyang Paul Bayendang Mohamed Tariq Kahn vipin Balyan Cape Peninsula University of Technology(CPUT) Bellville CampusSymphony Way(off Robert Sobukwe Road)Department of ElectricalElectronic and Computer Engineering(DEECE)7535Cape TownWestern CapeRepublic of South Africa

As the basis for the study,this manuscript was written at a time when the energy crisis is affecting most parts of the world and most es-pecially the prevailing and rampant electricity crisis in most developing *** a result,50 combined cooling,heating and power(CCHP)systems studies were reviewed,which included the internal combustion engine(ICE),Stirling engine,biomass,micro turbine,solar and biogas,photovoltaic(PV)and gas turbine,wind turbine,PV and micro-turbine,solid-oxide and phosphoric-acid fuel cells(FCs),ICE and thermoelectric generator,low-temperature(LT)polymer electrolyte membrane(PEM),inlet air throttling gas turbine,ground source heat pump(GSHP)micro gas turbine and PV,ICE and GSHP,ICE with dehumidification and refrigeration,5-kW PEM FC,thermoelectric cooler and LT-PEM FC,Stirling engine and molten carbonate FC,thermo-acoustic organic Rankine cycle,solar-thermal,geothermal,integrated energy systems,power-and heat-storage systems,energy-conversion systems,thermodynamic and thermo-economic optimization strategies,working fluids based on hydrogen,helium as well as ammonia,H_(2)O,CO_(2) *** these reviewed CCHP systems,FC-based CCHP systems were of the greatest interest,particularly the PEM ***,FCs were further investigated,whereby the seven popular types of FCs identified and classified were summarily compared with each other,from which the PEM FC was preferred due to its practical ***,PEM FCs,like all FCs,are susceptible to the fuel-starvation phenomenon;therefore,six FC-assisted schemes were examined,from which the FC assisted with the supercapacitor and battery technique was the most widely *** sum,the significance of the study entails assorted CCHP systems,FCs,their highlights,their applications and their pros and cons in a single reference document that anyone can easily use to holistically understand the characteristics of the CCHP *** study concludes with our perspective,by which we formulate and p

关键词： CHP/CCHP systems fuel cells full cells fuel starvation hybrid power and renewable energy

Antidiabetic,hypolipidemic and histopathological analysis of Dillenia indica (L.) leaves extract on alloxan induced diabetic rats

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Asian Pacific Journal of Tropical Medicine 2011年第5期4卷 347-352页

作者： Sunil Kumar vipin Kumar Om Prakash Institute of Pharmaceutical Sciences Kurukshetra UniversityHaryanaIndia

Objective:To investigate antidiabetic,hypolipidemic histopathological analysis of Dillenia indica(***) methanolic leaves(DIME) extract in alloxan induced diabetic rat by administering oral doses(250 and 500 mg/kg body weight).Methods:Blood glucose levels were measured using blood glucose test strips with elegance glucometer on weekly intervals till the end of study(i.e.3 weeks).Other parameters *** profile,renal profile and total lipid levels were determined in normal and alloxan induced diabetic rats after oral administration of the extract for 21 *** changes in diabetic rat organs(pancreas,liver and kidney) were also observed after extract treatment Results:Daily oral administration DIME(250 and 500 mg/kg body weight) and glibenclamide(10 mg/kg) showed beneficial effects on blood glucose level (P<0.001) as well as improving kidney,liver functions and hyperlipidaemia due to diabetes. The extract treatment also showed to enhanced serum insulin level and body weight of diabetic rats as compared to diabetic control ***,the extract has a favorable effect on the histopathological changes of the pancreas,liver and kidney in alloxan induced diabetes. Conclusions:*** possess antidiabetic property as well improve body weight,liver profile, renal profile and total lipid *** has also favorable effect to inhibit the histopathological changes of the pancreas and kidney in alloxan induced diabetes.

关键词： Antidiabetic Dillenia indica Hypolipidemic Rat Serum cholesterol