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Structural and mass transport properties of liquid ytterbium in the temperature range 1123 K–1473 K

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Chinese Physics b 2023年第6期32卷 481-488页

作者： d d Satikunvar N K bhatt b Y Thakore department of Physics Sardar Patel UniversityVallabh VidyanagarGujarat 388120India department of Physics Maharaja Krishnakumarsinhji Bhavnagar UniversityBhavnagarGujarat 364001India

We have studied the structural and atomic transport properties of liquid f-shell Yb in the temperature range 1123 K–1473 K. Pair interactions between atoms are derived using a local pseudopotential. The potential parameters are fitted to the phonon dispersion curve at room temperature. The local pseudopotential used in the present study is computationally more efficient with only three parameters, and it is found to be transferable to the liquid phase without changing the *** the various computed properties agree with reported theoretical and experimental findings, the adopted fitting scheme is justified. As a significant outcome of the study, we find that(i) the melting in Yb is governed by the Lindemann's law,(ii)the mass transport mechanism obeys the Arrhenius law,(iii) the role of the three-particle correlation function in deriving the velocity autocorrelation function is small,(iv) the mean-square atomic displacement is more sensitive to the choice of interaction potential than the other bulk properties, and(v) liquid Yb does not show liquid–liquid phase transition within the studied temperature range. Further, due to the good description of the structural and mass transport properties, we propose that Yb remains divalent at reduced density.

关键词： transport properties pseudopotential single-particle dynamics ytterbium

Image Captioning Using detectors and Swarm based Learning Approach for Word Embedding vectors

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Computer Systems Science & Engineering 2023年第1期44卷 173-189页

作者： b.Lalitha v.Gomathi CSE department Sethu Institute of TechnologyPulloorKariapatti626115India CSE department National Engineering CollegeK.R.NagarKovilpatti628503India

IC(Image Captioning)is a crucial part of visual data Processing and aims at understanding for providing captions that verbalize an image’s important ***,in existing works,because of the complexity in images,neglecting major relation between the object in an image,poor quality image,labelling it remains a big problem for ***,the main objective of this work attempts to overcome these challenges by proposing a novel framework for *** in this research work the main contribution deals with the framework consists of three phases that is image understanding,textual understanding and ***,the image understanding phase is initiated with image pre-pro-cessing to enhance image ***,object has been detected using IYv3MMds(Improved Yolov3 Multishot Multibox detectors)in order to relate the interrelation between the image and the object,and then it is followed by MbFOCNNs(Modified bacterial Foraging Optimization in Convolution Neural Networks),which encodes and providesfinal feature ***,the tex-tual understanding phase is performed based on an image which is initiated with preprocessing of text where unwanted words,phrases,punctuations are removed in order to provide a healthy *** is then followed by MGlovEs(Modified Glo-bal vectors for Word Representation),which provides a word embedding of fea-tures with the highest priority towards the object present in an ***,the decoding phase has been performed,which decodes the image whether it may be a normal or complex scene image and provides an accurate text by its learning ability using MdAA(Modified deliberate Adaptive Attention).The experimental outcome of this work shows better accuracy of shows 96.24%when compared to existing and similar methods while generating captions for images.

关键词： denoising improved Yolov3 multishot multibox detector

Hybrid deep Learning Method for diagnosis of Cucurbita Leaf diseases

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Computer Systems Science & Engineering 2023年第3期44卷 2585-2601页

作者： v.Nirmala b.Gomathy M.Kumarasamy College of Engineering KarurTamilnaduIndia K.P.R.Institute of Technology CoimbatoreTamilnaduIndia

In agricultural engineering,the main challenge is on methodologies used for disease *** manual methods depend on the experience of the *** to large variation in environmental condition,disease diagnosis and classification becomes a challenging *** from the disease,the leaves are affected by climate changes which is hard for the image processing method to discriminate the disease from the other *** Cucurbita gourd family,the disease severity examination of leaf samples through computer vision,and deep learning methodologies have gained popularity in recent *** this paper,a hybrid method based on Convolutional Neural Network(CNN)is proposed for automatic pumpkin leaf image *** Proposed denoising and deep Convolutional Neural Network(CNN)method enhances the Pumpkin Leaf Pre-processing and *** time data base was used for training and testing of the proposed *** on existing pre-trained network Alexnet and googlenet was investigated is done to evaluate the performance of the pro-posed *** system and computer simulations were performed using Matlab tool.

关键词： Cucurbita farming disease diagnosis classification Convolutional Neural Network(CNN) preprocessing deep learning

An Immersed Interface Method for the Simulation of Inextensible Interfaces in viscous Fluids

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Communications in Computational Physics 2012年第3期11卷 925-950页

作者： Zhijun Tan d.v.Le K.M.Lim b.C.Khoo Guangdong Province Key Laboratory of Computational Science&School of Mathematics and Computational Science Sun Yat-senUniversityGuangzhou 510275China Institute of High Performance Computing 1 Fusionopolis Way#16-16 ConnexisSingapore 138632Singapore Singapore-MIT Alliance 4 Engineering Drive 3National University of SingaporeSingapore 117576Singapore department of Mechanical Engineering National University of Singapore10 Kent Ridge CrescentSingapore 119260Singapore

In this paper,an immersed interface method is presented to simulate the dynamics of inextensible interfaces in an incompressible *** tension is introduced as an augmented variable to satisfy the constraint of interface inextensibility,and the resulting augmented system is solved by the GMRES *** this work,the arclength of the interface is locally and globally conserved as the enclosed region undergoes *** forces at the interface are calculated from the configuration of the interface and the computed augmented variable,and then applied to the fluid through the related jump *** governing equations are discretized on a MAC grid via a second-order finite difference scheme which incorporates jump contributions and solved by the conjugate gradient Uzawa-type *** proposed method is applied to several examples including the deformation of a liquid capsule with inextensible interfaces in a shear *** results reveal that both the area enclosed by interface and arclength of interface are conserved well *** provide further evidence on the capability of the present method to simulate incompressible flows involving inextensible interfaces.

关键词： Inextensible interface Stokes flows singular force immersed interface method CGUzawa method front tracking

Magnetic properties of melt-spun ribbons(Sm1-xZrx)(Fe0.92Ti0.08)10 with ThMn12 structure and their hydrides

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Journal of Rare Earths 2019年第10期37卷 1066-1071页

作者： A.G.Popov A.v.Protasov v.S.Gaviko d.A.Kolodkin P.b.Terentev E.G.Gerasimov Tianli Zhang Chengbao Jiang M.N.Miheev Institute of Metal Physics of Ural branch of Russian Academy of Sciences Str.S.Kovalevskoy18 Ekaterinburg620990Russia Institute of Natural Sciences and Mathematics Ural Federal Universitypr.Mira19 Ekaterinburg620002Russia School of Materials Science and Engineering Beihang UniversityBeijing 100191China

The structure and magnetic hysteresis properties of the cast Sm1-xZrx(Fe0.92Ti0.08)10(x = 0-0.3)alloys and melt-spun ribbons prepared from them were *** the cast alloy with x>0.2, a considerable amount of the eutectic phase is found in the SEM *** of the temperature dependences of the magnetic susceptibility and XRd patterns allows amorphous state in the as-spun ribbons with x>0.2 to be *** specific magnetization measured in a field of 17 kOe and remanence decrease with increasing annealing temperature from 800 to 900 ℃ and weakly depend on Zr *** maximal value of coercivity Hc = 4.7 kOe is obtained on the ribbons with x = 0.2 after annealing at 850℃ for 10 *** additional hydrogenation of the ribbons,both the coercivity and remanence increase by 54% and 7%,respectively.

关键词： Sm-Zr-Fe-Ti ThMn12 Melt-spun ribbons Hydrogenation Magnetic properties

Effect of synthesis conditions and surrounding medium on luminescence properties of YvO_4:Eu^(3+) nanopowders

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Journal of Rare Earths 2015年第2期33卷 129-134页

作者： E.v.Golyeva d.v.Tolstikova I.E.Kolesnikov M.d.Mikhailov St.Petersburg State Polytechnical University St.Petersburg 195251 Russia Scientific and Technological Institute of Optical Material Science VNTs S.I.Vavilov State Optical InstituteSt.Petersburg 192171 Russia St.Petersburg State University St.Petersburg 199034 Russia

Nanocrystalline yttrium vanadate doped with europium ions powders were synthesized via sol-gel method based on decomposition of metal-polymer complex. X-ray diffraction analysis showed that samples had pure tetragonal phase without any impurities. Scanning electron microscopy and static light scattering technique were used to study morphology and size of prepared nanoparticles. Average diameter of the nanoparticles was about 40 nm. The changes in structural and luminescence properties were observed as a function of the first and second calcination temperature. The optimal conditions for synthesis of nanoparticles were determined as Т1=500℃, t1=1 h; Т2=950 ℃, t2=1.5 h. The effect of different media surrounding the nanoparticles on their luminescence properties and lifetime was investigated and discussed in terms of effective refractive index. It was found that the observed lifetime of YvO4：Eu^3＋ 5 at.% nanophosphor was decreased from 0.64 ms in air（nmed=1） to 0.45 ms in chalcogenide glass As39S61（nmed=2.39）.

关键词： nanopowders rare earths luminescence effective refractive index lifetime

Additional Space dimension in bound Spaces Created by a Central Object

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Journal of Applied Mathematics and Physics 2015年第2期3卷 130-133页

作者： T. v. b. S. Satyanarayana murthy Civil design department of Power Projects division BGR Energy Systems Limited Chennai India

Space is a common entity in any static or dynamic system of objects whether the system is a bound system or an open system. Space is described by either measured or abstract dimensions. All motions, momentum and energy transfers take place in space in any given system of objects. by understanding space we understand many physical phenomena happening in space. One method is to observe similarities among phenomena, deduce possible relations and validate the relations through known results. de broglie wavelength for matter waves is a typical theorized abstract dimension existence of which is established through experiments later. In this paper, the author studies two bound spaces in two bound systems, namely, atomic bound systems and gravitationally bound systems. both these bound systems have similar characteristics;they have inertial masses in motion with constant kinetic energies for a given orbital distance around the respective central object. In atomic bound space, the central object is the central positive charge which plays the role of creating the bound space around it. In gravitationally bound space, it is the central mass that plays the same role. Thus for these two bound systems a common constitutive relation between the energies of inertial masses in kinetic state, their distance from central object could be present. by noticing the similarities of the two systems, the author proposes such a relation through introduction of an additional space dimension. The existence of the proposed additional dimension is proved in this paper by considering hydrogen atom for atomic bound space and by considering any gravitational system for gravitationally bound space. Though the magnitude of the additional space dimension is different in both the situations, the additional space dimension exists. It is observed that in hydrogen atom the additional space dimension is a constant for the given positive charge of hydrogen atom when electron is in any energy state having pri

关键词： Central Object bound Space Gravitational Charge Additional Space dimension Energy Mass

deNOx Study in diesel Engine Exhaust Using barrier discharge Corona Assisted by v_2O_5/TiO_2 Catalyst

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Plasma Science and Technology 2004年第4期6卷 2411-2415页

作者： b.S.Rajanikanth v.Ravi Indian Institute of Science Bangalore 560012IndiaIndian Institute of ScienceBangalore 560012India

A plasma-assisted catalytic reactor was used to remove nitrogen oxides (NOx)from diesel engine exhaust operated under different load conditions. Initial studies were focused onplasma reactor (a dielectric barrier discharge reactor) treatment of diesel exhaust at varioustemperatures. The nitric oxide (NO) removal efficiency was lowered when high temperature exhaust wastreated using plasma reactor. Also, NO removal efficiency decreased when 45% load exhaust wastreated. Studies were then made with plasma reactor combined with a catalytic reactor consisting ofa selective catalytic reduction (SCR) catalyst, v_2O_5/TiO_2. Ammonia was used as a reducing agentfor SCR process in a ratio of 1:1 to NOx. The studies were focused on temperatures of the SCRcatalytic reactor below 200℃. The plasma-assisted catalytic reactor was operated well to remove NOxunder no-load and load conditions. For an energy input of 96 J/l, the NOx removal efficienciesobtained under no-load and load conditions were 90% and 72% respectively at an exhaust temperatureof 100 ℃.

关键词： non-thermal plasma deNOx barrier discharge diesel exhaust

On Improving Accuracy of Finite-Element Solutions of the Effective-Mass Schr¨odinger Equation for Interdiffused Quantum Wells and Quantum Wires

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Communications in Theoretical Physics 2016年第1期65卷 105-113页

作者： d.b.Topalovi v.v.Arsoski S.Pavlovic N.A.Cukaric M.Z.Tadic F.M.Peeters School of Electrical Engineering University of Belgrade P.O. Box 35-54 11120 Belgrade Serbia vinca Institute of Nuclear Sciences University of Belgrade P.O. Box 522 11001 Belgrade Serbia department of Physics University of Antwerp Groenenborgerlaan 171 B-2020 Antwerp Belgium

We use the Galerkin approach and the finite-element method to numerically solve the effective-mass Schr¨odinger *** accuracy of the solution is explored as it varies with the range of the numerical *** model potentials are those of interdiffused semiconductor quantum wells and axially symmetric quantum ***,the model of a linear harmonic oscillator is considered for comparison *** is demonstrated that the absolute error of the electron ground state energy level exhibits a minimum at a certain domain range,which is thus considered to be *** range is found to depend on the number of mesh nodes N approximately as α_0 log_e^(α1)(α_2N),where the values of the constants α_0,α_1,and α_2are determined by fitting the numerical *** the optimal range is found to be a weak function of the diffusion ***,it was demonstrated that a domain range adaptation to the optimal value leads to substantial improvement of accuracy of the solution of the Schr¨odinger equation.

关键词： intermixing quantum well quantum wire Schrodinger equation finite element adaptive