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Elastodynamic analysis of anisotropic liquid-saturated porous medium due to mechanical sources

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Applied Mathematics and Mechanics(English Edition) 2007年第8期28卷 1049-1059页

作者： rajneesh Kumar Aseem Miglani n.r.Garg Department of Mathematics Kurukshetra University Kurukshetra-136 119India Department of Mathematics Guru Jambheshwar University of Science and Technology Hisar-125 001India Department of Mathematics Maharshi Dayanand University Rohtak-124 001India

Elastodynamic analysis of an anisotropic liquid-saturated porous medium is made to study a deformation problem of a transversely isotropic liquid-saturated porous medium due to mechanical sources. Certain physical problems are of the nature, in which the deformation takes place only in one direction, e.g., the problem relating to deformed structures and columns. In soil mechanics, an assumption of only vertical subsidence is often invoked and this leads to the one dimensional model of poroelasticity. By consid- ering a model of one-dimensional deformation of the anisotropic liquid-saturated porous medium, variations in disturbances are observed with reference to time and distance. The distributions of displacements and stresses are affected due to the anisotropy of the medium, and also due to the type of sources causing the disturbances.

关键词： elastodynamic anisotropic liquid-saturated porous laplace transform,impulsive and concentrated sources

Performance evaluation of minimum quantity lubrication by vege-table oil in terms of cutting force,cutting zone temperature,tool wear,job dimension and surface finish in turning AISI-1060 steel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1790-1799页

作者： KHAn M.M.A. DHAr n.r. Department of Industrial and Production Engineering Shahajalal University of Science and Technology Sylhet 3114 Bangladesh Department of Industrial and Production Engineering Bangladesh University of Engineering and Technology (BUET) Dhaka Bangladesh

In all machining processes, tool wear is a natural phenomenon and it leads to tool failure. The growing demands for high productivity of machining need use of high cutting velocity and feed rate. Such machining inherently produces high cutting temperature, which not only reduces tool life but also impairs the product quality. Metal cutting fluid changes the performance of machining operations because of their lubrication, cooling and chip flushing functions, but the use of cutting fluid has become more problematic in terms of both employee health and environmental pollution. The minimization of cutting fluid also leads to economical benefits by way of saving lubricant costs and workpiece/tool/machine cleaning cycle time. The concept of minimum quantity lubrication (MQL) has been suggested since a decade ago as a means of addressing the issues of environmental intru- siveness and occupational hazards associated with the airborne cutting fluid particles on factory shop floors. This paper deals with experimental investigation on the role of MQL by vegetable oil on cutting temperature, tool wear, surface roughness and dimen- sional deviation in turning AISI-1060 steel at industrial speed-feed combinations by uncoated carbide insert. The encouraging results include significant reduction in tool wear rate, dimensional inaccuracy and surface roughness by MQL mainly through reduction in the cutting zone temperature and favorable change in the chip-tool and work-tool interaction.

关键词： Minimum quantity lubrication (MQL) Cutting force Chip-tool interface temperature Tool wear Surface roughness Dimensional deviation

Continuous Symmetry Analysis of the Effects of City Infrastructures on Invariant Metrics for House Market Volatilities

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Computer Modeling in Engineering & Sciences 2022年第12期133卷 619-638页

作者： Chien-Wen Lin Jen-Cheng Wang Bo-Yan Zhong Joe-air Jiang Ya-Fen Wu Shao-Wei Leu Tzer-En nee Department of Electrical Engineering Taiwan Ocean UniversityKeelung20224Taiwan Department of Computer Science National Taipei University of EducationTaipei10671Taiwan Department of Electronic Engineering Chang Gung UniversityTao-Yuan City33302Taiwan Department of Biomechatronics Engineering National Taiwan UniversityTaipei10617Taiwan Department of Medical research China Medical University HospitalChina Medical UniversityTaichung40447Taiwan Department of Electronic Engineering Ming Chi University of TechnologyNew Taipei City24301Taiwan Artificial Intelligence research Center Chang Gung UniversityTao-Yuan City33302Taiwan

The invariant metrics of the effects of park size and distance to public transportation on housing value volatilities in Boston,Milwaukee,Taipei and Tokyo are *** reveal a Cobb-Douglas-like *** scaleinvariant exponents corresponding to the percentage of a green area(a)are 7.4,8.41,14.1 and 15.5 for Boston,Milwaukee,Taipei and Tokyo,respectively,while the corresponding direct distances to the nearest metro station(d)are−5,−5.88,−10 and−10,for Boston,Milwaukee,Taipei and Tokyo,*** multiphysics-based analysis provides a powerful approach for the symmetry characterization of market *** scaling exponent ratio between park area percentages and distances to metro stations is approximately 3/*** scaling exponent ratio expressed in the perceptual stimuli will remain invariant under group *** to Stevens’power law,the perception-dependent feature spaces for parks and public transportation can be described as two-and three-dimensional conceptual *** on the prolongation structure of the Schroinger equation,the SL(2,r)models are used to analyze the house-price *** with Shepard’s law,the rotational group leads to a Gaussian pattern,exhibiting an extension of the special linear group structure by embedding SO(3)■r(3)in SL(2,r).The influencing factors related to cognitive functioning exhibit substantially different scaleinvariant characteristics corresponding to the complexity of the socio-economic ***,the contour shapes of the price volatilities obtained from the group-theoretical analysis not only corroborate the impact of the housing pricing estimation in these cities but also reveal the invariant features of their housing markets are faced with the forthcoming sustainable development of big data technologies and computational urban science research.

关键词： Invariant metrics Schroinger equation group theory

Aberrant adult neurogenesis in intractable epilepsy:can GABAergic progenitor transplantation normalize this process?

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neural regeneration research 2024年第7期19卷 1419-1420页

作者： Muhammad n.Arshad Janice r.naegele Department of Biology Wesleyan UniversityMiddletownCTUSA Department of neuroscience Tufts University School of MedicineBostonMAUSA

Temporal lobe epilepsy(TLE) is a common type of focal epilepsy characterized by seizure foci within the temporal *** surgical resection of the foci is an established and effective approach for controlling seizures,both temporal lobes cannot be removed,due to their prominent roles in learning and ***,seizures induce changes to the temporal lobes that contribute to hyperexcitability,including mossy fiber sprouting,astrogliosis.

关键词： epilepsy progenitor seizures

Electroosmotic Flow of MHD Power Law Al_2O_3-PVC nanofluid in a Horizontal Channel: Couette-Poiseuille Flow Model

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Communications in Theoretical Physics 2018年第6期69卷 655-666页

作者： n.Shehzad A.Zeeshan r.Ellahi Department of Mathematics and Statistics FBAS IIUI

The current manuscript is reported about the eiectro-osmotic Couette-Poiseuille ftow of power law Al2O3- PVC nanofluid through a channel, in which upper wall is moving with constant velocity. The influences of magnetic field, mixed convection, joule heating, and viscous dissipation are also incorporated. The flow is generated because of constant pressure gradient in axial direction. The resulting flow problem is coupled nonlinear ordinary differential equations, which are at first modeled and then transform into dimensionless form through appropriate transformation. Analytical solution of the governing is carried out. The impact of modified Brinkman number, modified Magnetic field, electro-osmotic parameters on velocity and temperature are examined graphically. From the results, it is concluded that the Skin friction at moving isolated wail decreases with the increase of electro-osmotic parameter and reverse behavior for nusselt number at heated stationary wall occur.

关键词： Couette-Poiseuille flow power law nanofluid electro-osmotic flow MHD PVC Alumina

Dynamics of lattice disorder in perovskite materials, polarization nanoclusters and ferroelectric domain wall structures

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npj Computational Materials 2023年第1期9卷 1137-1149页

作者： Jan Očenášek Ján Minár Jorge Alcalá new Technologies research Centre University of West Bohemia in Pilsen30614 PlzeňCzech Republic Department of Materials Science and Metallurgical Engineering InSupETSEIBUniversitat Politècnica de Catalunya08028 BarcelonaSpain

The nexus between classic ferroelectricity and the structure of perovskite materials hinges on the concept of lattice *** the ordered perovskites display short-range displacements of the central cations around their equilibrium points,the lattice disorder dynamically unfolds to generate a myriad of distorted rhombohedral lattices characterized by the hopping of the central cations across*** is discovered that the lattice disorder correlates with the emergence of minimum configuration energypathways for the central cations,resulting in spatially modulated ultrafast polarization nanocluster arrangements that are stabilized by the electric charge defects in the *** high-resolution phonon dispersion analyses encompassing molecular dynamics(MD)and density functional theory(DFT)simulations,we provide unequivocal evidence linking the hopping of central cations to the development of diffuse soft phonon modes observed throughout the phase transitions of the *** massive MD simulations,we unveil the impact of lattice disorder on the structures of domain walls at finite-temperature vis-à-vis collective activation and deactivation of***,our simulations demonstrate the development of hierarchical morphotropic phase boundary(MPB)nanostructures under the combined influence of externally applied pressure and stress relaxation,characterized by sudden emergence of zig-zagged monoclinic arrangements that involve dualshifts of the central *** findings have implications for tailoring MPBs in thin-film structures and for the light-induced mobilization of *** are finally uncovered to the exploration of lattice disorder through gradual shear strain application.

关键词： perovskite lattice ferroelectric

Thermal Efficiency for Each Zone of a Solar Pond

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Chinese Physics Letters 2011年第10期28卷 281-283页

作者： BEZİr CİCEK nalan ŞAHİnŞEnCAn Arzu Department of Physics Faculty of ScienceSuleyman Demirel UniversityTurkey Department of Mechanical Education Technical Education FacultySüleyman Demirel UniversityTurkey

A salt gradient solar pond with a surface area of 3.5×3.5 m^(2) and a depth of 2 m is *** collapsible covers are used to reduce thermal energy loss from the surface of the solar pond during the night and to increase the thermal efficiency of the pond solar energy harvesting during *** covers can be rotated between 0 and 180°by a controlled electric motor and has insulation and reflection *** thermal efficiency for each solar pond zone is investigated theoretically and experimentally.

关键词： properties insulation harvesting

Experimental study on microstructural and corrosion behaviors of friction stir processed steel with CoCrFeCuTi HEA reinforcement and effect of annealing

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Science China Technological Sciences 2025年第1期 233-250页

作者： S.Aravind KrISHnA n.rADHIKA Alokesh PrAMAnIK n.JEYAPrAKASH Department of Mechanical Engineering Amrita School of EngineeringAmrita Vishwa Vidyapeetham School of Civil and Mechanical Engineering Curtin University School of Mechanical and Electrical Engineering China University of Mining and Technology

The ability to perform against extreme corrosion environments in stainless steel depreciates under challenging conditions in industrial applications. This can be resolved by employing surface modification techniques to modify the surface with the required characteristics. The present study investigates the outcomes of friction stir processing of SS304 with CoCrFeCuTi high entropy alloy(HEA) as reinforcement and the property enhancements post-annealing. The synthesized CoCrFeCuTi HEA exhibited irregular fragments with 17 μm mean particle size and body centred cubic(BCC) phase. The microstructure of the processed surface revealed ultra-refined grains with a uniform distribution of HEA filler. The microstructures of the samples annealed at 400℃, 550℃, 700℃ and 850℃ for 2 h also showed significant grain growth and grain refinements. The processed sample with HEA reinforcement annealed at 700℃ exhibited enhanced microhardness and tensile strength by 63% and 0.88 times than that of the processed sample with HEA pre-annealing. The subsequent electrochemical corrosion test displayed better corrosion resistance for the HEA-processed and annealed sample. Hot corrosion tests at 900℃ showcased excellent resistance for the HEA processed and annealed samples by 14.92%, 12.75%, and 14.83% against the samples pre-annealed under three different salt mixtures, and the corroded surface was analyzed.

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Impact of Clocking on the Aero-Thermodynamics of a Second Stator tested in a One and a Half Stage HP Turbine

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Journal of Thermal Science 2008年第2期17卷 97-110页

作者： n.Billiard G.Paniagua r.Dénos Turbomachinery and Propulsion Department von Karman Institute for Fluid Dynamics

This paper focuses on the experimental investigation of the time-averaged and time-accurate aero- thermodynamics of a second stator tested in a 1.5 stage high-pressure turbine. The effect of clocking on aerodynamic and heat transfer are investigated. Tests are performed under engine representative conditions in the VKI compression tube CT3. The test program includes four different clocking positions, i.e. relative pitch-wise positions between the fh-st and the second stator. Probes located upstream and downstream of the second stator provide the thermodynamic conditions of the flow field. On the second stator airfoil, measurements are taken around the blade profile at 15, 50 and 85% span with pressure sensors and thin-film gauges. Both time-averaged and time-resolved aspects of the flow field are addressed. regarding the time-averaged results, clocking effects are mainly observed within the leading edge region of the second stator, the largest effects being observed at 15% span. The surface static pressure distribution is changed locally, hence affecting the overall airfoil performance. For one clocking position, the thermal load of the airfoil is noticeably reduced. Pressure fluctuations are attributed to the passage of the up- stream transonic rotor and its associated pressure gradients. The pattern of these fluctuations changes noticeably as a function of docking. The time-resolved variations of heat flux and static pressure are analyzed together showing that the major effect is due to a potential interaction. The time-resolved pressure distribution integrated along the second stator surface yields the unsteady forces on the vane. The magnitude of the unsteady force is very dependent on the clocking position.

关键词： transonic flow turbines stator clocking forces heat transfer.