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Kinematic and Dynamic Analysis of a 3-■US Spatial Parallel Manipulator

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Chinese Journal of Mechanical Engineering 2020年第1期33卷 114-130页

作者： Mervin Joe Thomas M.l.joy A.P.Sudheer Mechatronics/Robotics lab Department of Mechanical EngineeringNational Institute of Technology CalicutKozhikodeIndia

Parallel Kinematic Machines(PKMs)are being widely used for precise applications to achieve complex motions and variable poses for the end effector *** are found in medical,assembly and manufacturing industries where accuracy is *** is often desired to have a compact and simple architecture for the robotic *** this paper,the kinematic and dynamic analysis of a novel 3-PRUS(P:prismatic joint,R:revolute joint,U:universal joint,S:spherical joint)parallel manipulator with a mobile platform having 6 Degree of Freedom(Do F)is *** kinematic equations for the proposed spatial parallel mechanism are formulated using the Modified Denavit-Hartenberg(DH)technique considering both active and passive *** kinematic equations are used to derive the Jacobian matrix of the mechanism to identify the singular points within the workspace.A Jacobian based sti ness analysis is done to understand the variations in sti ness for different poses of the mobile platform and further,it is used to decide trajectories for the end effector within the singularity free *** analytical model of the robot dynamics is presented using the Euler-lagrangian approach with lagrangian multipliers to include the system *** gravity and inertial forces of all links are considered in the mathematical *** analytical results of the dynamic model are compared with ADAMS simulation results for a pre-defined trajectory of the end effector.

关键词： Parallel manipulator Kinematic modelling Workspace analysis Euler-lagrangian modelling Singularity analysis Stiffness analysis

lithium-ion mobility in layered oxides li_(2)Ca_(1.5)Nb_(3)O_(10),li_(2)Ca_(1.5)TaNb_(2)O_(10)and li_(2)Ca_(1.5)Ta_(2)NbO_(10),enhanced by supercell formation

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Journal of Energy Chemistry 2021年第9期30卷 75-84页

作者： Selorm joy Fanah Farshid Ramezanipour Department of Chemistry University of LouisvilleLouisvilleKY 40292USA

The formation of a supercell and its impact on lithium-ion conductivity have been studied through synthesis of three layered oxides,li_(2)Ca_(1.5)Nb_(3)O_(10),li_(2)Ca_(1.5)TaNb_(2)O_(10)and li_(2)Ca_(1.5)Ta_(2)NbO_(10),related to Ruddlesden-Popper *** diffraction experiments show that these materials feature a supercell,which is significantly larger(√2a×√2b×1c)than that of a typical RuddlesdenPopper *** impedance spectroscopy shows that the formation of the new supercell is associated with enhanced lithium-ion conductivity of these materials as compared with the Sranalogue,li_(2)Sr_(1.5)Nb_(3)O_(10),which lacks the *** addition,a systematic trend is observed in the ionic conductivity:li_(2)Ca_1.5Ta_(2)NbO10li_(2)Ca_(1.5)TaNb_(2)O_(10)li_(2)Ca_(1.5)Nb_(3)O_(10).The Arrhenius analysis in the temperature range 25–400°C shows that activation energy for the temperature-dependent rise in conductivity follows a similar *** analyses of real and imaginary components of impedance,dielectric properties,tangent loss,and complex modulus show the systematic increase in lithium-ion *** dielectric values mirror the same trend as ionic conductivity,where the most conductive material shows the highest dielectric *** addition,the same trend is observed in the peak and dispersion of dielectric loss and complex modulus as a function of angular frequency,indicating a systematic rise in lithium-ion *** fundamental study is aimed at exploring the impact of structural modifications on ionic conductivity in solids.

关键词： lithium-ion Conductivity Supercell Impedance Dielectric analyses

lepton and quark mixing patterns with generalized CP transformations

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Chinese Physics C 2022年第10期46卷 25-42页

作者： joy Ganguly Raghavendra Srikanth Hundi Department of Physics Indian Institute of Technology HyderabadKandi-502284India

In this study,we modify a scenario,originally proposed by Grimus and lavoura,in order to obtain maximal values for the atmospheric mixing angle and CP,violating the Dirac phase of the lepton *** achieve this,we employ CP and some discrete symmetries in a type Ⅱ seesaw *** make predictions about the neutrino mass ordering and smallness of the reactor angle,we establish some conditions on the elements of the neutrino mass matrix of our ***,we study the quark masses and mixing pattern within the framework of our model.

关键词： neutrino physics nuetrino mass and mixing model quark mass and mixing analysis of scalar potential

The effect of bacterial challenge on ferritin regulation in the yellow fever mosquito, Aedes aegypti

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Insect Science 2013年第5期20卷 601-619页

作者： Dawn l. Geiser Guoli Zhou Jonathan J. Mayo joy J. Winzerling Department of Nutritional Sciences College of Agriculture and Life Sciences the University of Arizona Tucson Arizona 85721 USA

Secreted ferritin is the major iron storage and transport protein in insects. Here, we characterize the message and protein expression profiles of yellow fever mosquito （Aedes aegypti） ferritin heavy chain homologue （HCH） and light chain homologue （lCH） subunits in response to iron and bacterial challenge. In vivo experiments demonstrated tissue-specific regulation of HCH and lCH expression over time post-blood meal （PBM）. Transcriptional regulation of HCH and lCH was treatment specific, with differences in regulation for na？ve versus mosquitoes challenged with heat-killed bacteria （HKB）. Translational regulation by iron regulatory protein （IRP） binding activity for the iron-responsive element （IRE） was tissue-specific and time-dependent PBM. However, mosquitoes challenged with HKB showed little change in IRP/IRE binding activity compared to na？ve animals. The changes in ferritin regulation and expression in vivo were confirmed with in vitro studies. We challenged mosquitoes with HKB followed by a blood meal to determine the effects on ferritin expression, and demonstrate a synergistic, time-dependent regulation of expression for HCH and lCH.

关键词： Aedes aegypti bacteria ferritin iron IRP mosquito

The IUGS Commission on Geological Sciences for Environmental Planning （COGEOENVIRONMENT） completes its term

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Episodes 2005年第1期28卷 64-65页

作者： joy Pereira Institute for Environment and Development LESTARI Universiti Kebangsaan Malaysia

During the last 2 years the IUGS has reviewed its Organisation and Operations to allow more efficient and effective administration into the future. Among the items reviewed was the life of Commissions which have now been defined at a maximum of 8 years. As a consequence COGEOENVIRONMENT, which has been in existence since early 1990, was formally closed down at the IGC in Florence in August 2004. The decision by the IUGS Council to close COGEOENVIRONMENT did not in any way imply that the role of the IUGS in promoting geoscience in environment matters was completed.

关键词：地质学环境规划 IUGS 工作思路发展目标

Heterogeneous molecular catalysts for electrocatalytic CO2 reduction

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Nano Research 2019年第9期12卷 2093-2125页

作者： Nathan Corbin joy Zeng Kindle Williams Karthish Manthiram Department of Chemical Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

This review provides an overview of the literature regarding heterogeneous molecular catalysts for electrochemical CO2 reduction (ECR).Fundamental aspects of the science,including aggregation,electrochemical rate laws,and electrode-catalyst electronic coupling,are discussed to provide a solid foundation on which to design experiments and interpret *** aspects of ECR are presented based on electrokinetic and spectroscopic measurements as well as density functional theory (DFT) *** is improving for electrokinetic measurements,but the redox state of the metal center under reaction conditions and DFT reaction pathways lack agreement in the *** the tunable aspects of the molecular catalyst,the impacts of the metal center,ligand substituents,and electrode support on the activity and selectivity toward ECR are presented with an emphasis on those studies that controlled for aggregation and minimized mass-transport *** three-dimensional (3D) structures such as polymers,metal-organic frameworks (MOFs),and covalent-organic frameworks (COFs) are discussed as highly tunable architectures that begin to mimic the catalytic pockets of enzyme active *** achieve the full potential of these catalysts,design principles must emerge based on a combination of deconvoluting measurements to extract intrinsic catalyst properties and more reliable theoretical calculations to predict reaction pathways.

关键词： CO2 reduction electrocatalysis porphyrins phthalocyanines molecular complexes heterogeneous catalysis

Macrophage Nrf2,an anti-inflammatory signal in hepatic ischemia/reperfusion injury

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Cellular & Molecular Immunology 2023年第5期20卷 427-428页

作者： joy X.Jiang Department of Molecular Biosciences UC DavisRm.30091089 Veterinary Medicine Dr.DavisCA95616US

Recently,the manuscript entitled Macrophage nuclear factor erythroid 2-related factor 2(Nrf2)deficiency promotes innate immune activation by tissue inhibitor of metalloproteinase 3(Timp3)-mediated RhoA/ROCK pathway in the ischemic liver by Rao and colleagues in Hepatology 2022,vol.75[1]described a novel role of Nrf2 in innate immunity in response to hepatic ischemia/reperfusion injury(IRI).Nrf2 is generally considered a redox signaling controller and drives protective signals as an antioxidant gene in multiple organs and diseases.

关键词： Nrf2 hepatic Macrophage

Uncomfortable prototypes： Rethinking socio-cultural factors for the design of public housing in Billiri, north east Nigeria

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Frontiers of Architectural Research 2013年第3期2卷 310-321页

作者： joy Joshua Maina School of the Built Environment University of Nottingham Nottingharn NG7 2RD UK

Public housing delivery in developing countries often involves the provision of government- funded housing units. Over time, occupants transform such units to suit their changing needs or to increase and improve housing stock-a practice that has been the focus of several documented studies intended to inform policy makers about changing housing trends. Abandoned units have, however, received comparatively less attention. The present paper reports findings from the documentation and analyses of abandoned and modified prototype units in Billiri, the main town occupied by the Tangale community in north east Nigeria. The methodology involves space syntax methods, as well as the analyses of space use patterns in 45 randomly selected compounds built by the community and in two sets of prototype housing units in the study area. Results suggest that socio-cultural factors related to kinship, security, and basic needs, which form part of the community heritage, are inadequately reflected in the location and design of the units, accounting for their abandonment and modification. These findings have implications for future housing policies in the area.

关键词： Public housing Prototype units Socio-cultural factorsTangale land North east Nigeria

Security and Privacy in Metaverse: A Comprehensive Survey

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Big Data Mining and Analytics 2023年第2期6卷 234-247页

作者： Yan Huang Yi(joy)li Zhipeng Cai Department of Software Engineering and Game Development Kennesaw State UniversityAtlantaCA 30060USA Department of Computer Science Georgia State UniversityAtlantaCA 30303USA

Metaverse describes a new shape of cyberspace and has become a hot-trending word since *** are many explanations about what Meterverse is and attempts to provide a formal standard or definition of ***,these definitions could hardly reach universal *** than providing a formal definition of the Metaverse,we list four must-have characteristics of the Metaverse:socialization,immersive interaction,real world-building,and *** characteristics not only carve the Metaverse into a novel and fantastic digital world,but also make it suffer from all security/privacy risks,such as personal information leakage,eavesdropping,unauthorized access,phishing,data injection,broken authentication,insecure design,and *** paper first introduces the four characteristics,then the current progress and typical applications of the Metaverse are surveyed and categorized into four economic *** on the four characteristics and the findings of the current progress,the security and privacy issues in the Metaverse are *** then identify and discuss more potential critical security and privacy issues that can be caused by combining the four ***,the paper also raises some other concerns regarding society and humanity.

关键词： Metaverse cybersecurity privacy protection cyber infrastructure extended reality