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Computers, materials & Continua 2017年第1期53卷 49-72页

作者： A.m.Abd-Alla S.m.Abo-Dahab Aftab Khan math.Dept. Faculty of ScienceTaif University 888Saudi Arabia math.Dept. Faculty of ScienceSohag UniversityEgypt math.Dept. Faculty of ScienceSVUQena 83523Egypt Department of mathematics COMSATSInstitute of InformationPark RoadChakshahzadIslamabadPakistan

In this paper, we investigated the propagation of magneto-thermoelastic surfacewaves in fibre-reinforced anisotropic general viscoelastic media of higher order ofnth order,including time rate of strain under the influence of rotation and magnetic *** generalsurface wave speed is derived to study the effects of rotation, magnetic field and thermal onsurface waves. Particular cases for Stoneley, Love and Rayleigh waves are discussed. Theresults obtained in this investigation are more general in the sense that some earlier publishedresults are obtained from our result as special cases. Our results for viscoelastic of order zeroare well agreed to fibre-reinforced materials. Comparison was made with the results obtainedin the presence and absence of rotation, magnetic field and parameters for fibre-reinforced ofthe material medium. It is also observed that, surface waves cannot propagate in a fast rotatingmedium. Numerical results for particular materials are given and illustrated graphically. Theresults indicate that the effect of rotation, magnetic field on fibre-reinforced anisotropic generalviscoelastic media are very pronounced.

关键词： ibre-reinforced viscoelastic surface waves rotation anisotropic thermoelastic magnetic

Same Concept Different Outcomes:Sugars Determine Circadian Clock Protein Fate in Animals and Plants

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molecular Plant 2020年第3期13卷 360-362页

作者： Wei Liu Joshua m.Gendron Department of molecular Cellular and Developmental BiologyYale UniversityNew HavenCT 06511USA

most eukaryotes have a self-sustaining circadian clock that senses environmental cues and the internal metabolic state and then imposes daily temporal organization of the *** clock,by nature,regulates the daily creation and destruction of a large quantity of RNA and proteins,including those at the core of the oscillator *** a transcriptional-translational feedback loop maintains the rhythmicity of the oscillator,various post-translational modifications(PTms)of clock proteins play fundamental roles in keeping the pace of the circadian clock near 24 *** maintain circadian clock pacing,PTms act to ensure the rapid,efficient,and precise activation,inactivation,and finally destruction of core clock proteins(Hirano et al.,2016).

关键词： maintain oscillator precise

Forced vibration analysis of nano-composite rotating pressurized microbeam reinforced by CNTs based on mCST with temperature-variable material properties

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Theoretical & Applied mechanics Letters 2018年第2期8卷 97-108页

作者： R.Rostami m.mohammadimehr m.Ghannad A.Jalali Department of Solid mechanics Faculty of Mechanical EngineeringShahrood University of Technology Department of Solid mechanics Faculty of Mechanical EngineeringUniversity of Kashan

In this study, free and forced vibration analysis of nano-composite rotating pressurized microbeam reinforced by carbon nanotubes （CNTs） under magnetic field based on modify couple stress theory （mCST） with temperature-variable material propertiesis presented. Also, the boundary conditions at two ends of nano-composite rotating pressurized microbeam reinforced by CNTs are considered as simply supported. The governing equations are obtained based on the Hamilton＇s principle and then computed these equations by using Navier＇s solution. The magnetic field is inserted in the thickness direction of the nano-composite microbeam. The effects of various parameters such as angular velocity, temperature changes, and pressure between of the inside and outside, the magnetic field, material length scale parameter, and volume fraction of nanocomposite microbeam on the natural frequency and response systemare studied. The results show that with increasing volume fraction of nano-composite microbeam, thickness, material length scale parameter, and magnetic fields, the natural frequency increases. The results of this research can be used for optimization of micro-structures and manufacturing sensors, displacement fluid, and drug delivery.

关键词： Forced vibration analysis Nano-composite rotating pressurized microbeam Carbon nanotubes modify couple stress theory Temperature-variable material properties

Dust Acoustic Solitary Waves in Saturn F-ring's Region

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Communications in Theoretical Physics 2011年第1期55卷 143-150页

作者： E.K.El-Shewy m.I.Abo el maaty H.G.Abdelwahed m.A.Elmessary Theoretical Physics Group Faculty of ScienceMansoura University mathematics and Physics Department Faculty of Engineering Mansoura University

Effect of hot and cold dust charge on the propagation of dust-acoustic waves （DAWs） in unmagnetized plasma having electrons, singly charged ions, hot and cold dust grains has been investigated. The reductive perturbation method is employed to reduce the basic set of fluid equations to the Kortewege-de Vries （KdV） equation. At the critical hot dusty plasma density Nho, the KdV equation is not appropriate for describing the system. Hence, a set of stretched coordinates is considered to derive the modified KdV equation. It is found that the presence of hot and cold dust charge grains not only significantly modifies the basic properties of solitary structure, but also changes the polarity of the solitary profiles. In the vicinity of the critical hot dusty plasma density Nho, neither KdV nor mKdV equation is appropriate for describing the DAWs. Therefore, a further modified KdV （fmKdV） equation is derived, which admits both soliton and double layer solutions.

关键词： dust-acoustic waves hot and cold dust charge double layer solutions

Emission of high-energy alpha particles in nuclear reactions of ^(48)Ca and ^(56)Fe ions on ^(181)Ta and ^(238)U targets

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Chinese Physics C 2022年第11期46卷 177-194页

作者： Yu.E.Penionzhkevich V.V.Samarin S.m.Lukyanov V.A.maslov m.A.Naumenko Flerov Laboratory of Nuclear Reactions Joint Institute for Nuclear ResearchDubna 141980Russia Department of Experimental methods in Nuclear Physics National Research Nuclear UniversityMoscow 115409Russia Department of Nuclear Physics Dubna State UniversityDubna 141982Russia

The results of experiments on measuring the energy spectra of alpha particles in reactions with heavy ions are *** measurements were performed using the high-resolution magnetic analyzer mAVR with beams of ^(48)Ca(280 meV)and ^(56)Fe(320 and 400 meV)on ^(181)Ta and ^(238)U targets at an angle of 0°.A strong dependence of the double differential cross sections for production of alpha particles on the atomic number of the target nucleus was observed,which indicates that fast alpha particles are mainly emitted from the target nucleus;this conclusion was also confirmed by calculations within the time-dependent Schrödinger equation *** analysis of the obtained experimental data was carried out within the model of moving sources modified to consider the kinematic limits for two-body and three-body exit channels.

关键词： alpha particle energy spectra two-and three-body kinematic limits model of moving sources time-dependent Schrodinger equation

Vibrational characteristics of piping system in air conditioning outdoor unit

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Science China(Technological Sciences) 2011年第5期54卷 1154-1168页

作者： S. K. LOH W. F. FARIS m. HAmDI W. m. CHIN Department of Engineering Design & manufacture Faculty of Engineering University of Malaya Department of mechanical Engineering College of Engineering International Islamic University Malaysia O.Y.L. R&D Sdn Bhd Sungai Buloh Selangor Darul Ehsan Malaysia

The modal analysis of piping system in air conditioner (AC) outdoor unit is essential to investigate the vibration properties of the system. In view of the growing significance of numerical finite element (FE) model for vibration behaviour prediction, the AC piping elastic end support characterization has been explored. The axial and radial stiffness variables (ka, kr1, kr2) of the compressor-piping mounting are obtained and represented by dynamic stiffness of compressor grommet. They are obtained from dynamic load deflection test based on compressor operating condition such as excitation frequency and amplitude. The unknown stiffness variables of the other tube end (chassis-piping mounting) are determined by parameter fine tuning. An experimental modal analysis using impact hammer test has also been employed to determine the vibration properties such as natural frequencies, mode shapes and damping ratio of the piping structures. The modal parameters acquisition using SCADAS mobile acquisition system and LmS Impact Testing software is compared with the corresponding simulated modal properties using Abaqus. most of the simulated natural frequencies achieve good correlation with the measured frequencies and it is reasonably a good prediction model to predict vibration behaviour of AC piping structures.

关键词： air conditioning outdoor unit piping modal analysis vibration characteristics

Efficient Resource Allocation in Fog Computing Using QTCS model

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Computers, materials & Continua 2022年第2期70卷 2225-2239页

作者： m.Iyapparaja Naif Khalaf Alshammari m.Sathish Kumar S.Siva Rama Krishnan Chiranji Lal Chowdhary School of Information Technology and Engineering Vellore Institute of TechnologyVellore632014India mechanical Engineering University of HailSaudi Arabia

Infrastructure of fog is a complex system due to the large number of heterogeneous resources that need to be *** embedded devices deployed with the Internet of Things(IoT)technology have increased since the past few years,and these devices generate huge amount of *** devices in IoT can be remotely connected and might be placed in different locations which add to the network *** time applications require high bandwidth with reduced latency to ensure Quality of Service(QoS).To achieve this,fog computing plays a vital role in processing the request locally with the nearest available resources by reduced *** of themajor issues to focus on in a fog service is managing and allocating *** theory is one of the most popular mechanisms for task *** this work,an efficient model is designed to improve QoS with the efficacy of resource allocation based on a Queuing Theory based Cuckoo Search(QTCS)model which will optimize the overall resource management process.

关键词： Queuing theory Cuckoo search QoS resource allocation energy efficiency

Introduction of Damping,Synchronizing and Inertial Effects Using Controlled Power Injection Devices

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CSEE Journal of Power and Energy Systems 2017年第4期3卷 408-418页

作者： Kaustav Dey P.Agnihotri A.m.Gole A.m.Kulkarni Department of Electrical Engineering Indian Institute of TechnologyBombayIndia Department of Electrical and Computer Engineering University of ManitobaCanada

This paper presents a theoretical study of damping,synchronizing and inertial control laws,implemented using controllable power injection devices like HVDC,FACTS or renewable-energy/storage systems which have power-electronic grid *** approach is to use a simplified dynamical model of a power system to arrive at generalized results regarding the effect of the strategies on the electro-mechanical dynamics of the *** results are not dependent on the size,network topology and operating condition of the power *** paper presents a differential-algebraic formulation and generalized eigenvalue analysis to facilitate a unified study of the effects of the control laws on the electro-mechanical *** damping,synchronizing and inertial control laws can themselves be extended to include the possibility of mutualdamping,synchronizing and inertial effects when multiple devices are *** control laws are not only simple and intuitive,but also are found to have a predictable and generally beneficial impact on the electro-mechanical dynamics of the grid,even when detailed models are considered.

关键词： Dynamic stability high voltage direct current(HVDC) inertia emulation power system control

ImPROVEmENT OF TYPE IV CRACKING RESISTANCE OF 9Cr HEAT RESISTING STEEL WELDmENT BY BORON ADDITION

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Acta metallurgica Sinica(English Letters) 2004年第4期17卷 331-337页

作者： m.Tabuchi m.Kondo T.Watanabe H.Hongo F.Yin F.Abe National Institute for materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 JapanNational Institute for Materials Science Tsukuba Ibaraki 305-0047 Japan

Creep lives of high Cr ferritic heat resisting steel weldments decrease due to Type Ⅳ fracture, which occurs as a result of formation and growth of creep voids and cracks on grain boundaries in fine-grained heat affected zone (HAZ). Because boron is considered to suppress the coarsening of grain boundary precipitates and growth of creep voids, we have investigated the effect of boron addition on the creep properties of 9Cr steel weldments. Four kinds of 9Cr3WSCoVNb steels with boron content varying from 4.7×10-5 to 1.8×10-4 and with nitrogen as low as 2.0×10-5 were prepared. The steel plates were welded by gas tungsten arc welding and crept at 923K. It was found that the microstructures of HAZ were quite different from those of conventional high Cr steels such as P91 and P92, namely the fine-grained HAZ did not exist in the present steel weldments. Boron addition also has the effect to suppress coarsening of grain boundary carbides in HAZ during creep. As a result of these phenomena, the welded joints of present steels showed no Type Ⅳ fractures and much better creep lives than those of conventional steels.

关键词： high Cr heat resistant steel welded joint boron addition Type IV fracture

Determinants of the Specif icity of Protein Targeting to Chloroplasts or mitochondria

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molecular Plant 2019年第7期12卷 893-895页

作者： Lucas mcKinnon Steven m.Theg Department of Plant Biology University of California Davis Davis CA USA

Chloroplasts and mitochondria are both thought to have arisen through primary endosymbiosis (Kutschera and Niklas, 2005). As each organelle evolved, most of its genome was transferred to the host nucleus resulting in the vast majority of its proteome being nuclear encoded and synthesized on cytosolic ribosomes (Shi and Theg, 2013).

关键词： Chloroplasts mitochondria