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saddle Point Criteria in Nonsmooth semi-Infinite Minimax Fractional Programming Problems

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Journal of systems science & Complexity 2018年第2期31卷 446-462页

作者： MIsHRA s k sINGH Yadvendra VERMA R u Department of Mathematics Banaras Hindu University Varanasi-221005 India. Department of Mathematics Texas State University USA

This paper considers a nonsmooth semi-infinite minimax fractional programming problem（sIMFP） involving locally Lipschitz invex functions. The authors establish necessary optimality conditions for sIMFP. The authors establish the relationship between an optimal solution of sIMFP and saddle point of scalar Lagrange function for sIMFP. Further, the authors study saddle point criteria of a vector Lagrange function defined for sIMFP.

关键词： Generalized convexity Lagrange function nonsmooth programming problems saddlepoint semi-infinite minimax fractional programming problems.

Hybrid Active Contour Mammographic Mass segmentation and Classification

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Computer systems science & Engineering 2022年第3期40卷 823-834页

作者： k.Yuvaraj u.s.Ragupathy Department of Electronics and Instrumentation Engineering Kongu Engineering College PerunduraiErode638060India

This research implements a novel segmentation of mammographic *** methods are proposed,namely,segmentation of mass based on iterative active contour,automatic region growing,and fully automatic mask selectionbased active contour *** the first method,iterative threshold is performed for manual cropped preprocessed image,and active contour is applied *** overcome manual cropping in the second method,an automatic seed selection followed by region growing is *** that the result is only a few images owing to over segmentation,the third method uses a fully automatic active *** of the segmentation techniques are compared with the manual markup by experts,specifically by taking the difference in their mean ***,the difference in the mean value of the third method is 1.0853,which indicates the closeness of the ***,the proposed method is compared with the existing fuzzy C means and level set *** automatic mass segmentation based on active contour technique results in segmentation with high *** using adaptive neuro fuzzy inference system,classification is done and results in a sensitivity of 94.73%,accuracy of 93.93%,and Mathew’s correlation coefficient(MCC)of 0.876.

关键词： Feature optimization hybrid active contour segmentation mass classification mass feature extraction medical image analysis

Thermal Properties of Ni–Cr–si–B–Fe Based Interlayer Material and Its Application in TLP Bonding of IN 718 superalloy

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Acta Metallurgica sinica(English Letters) 2020年第12期33卷 1666-1680页

作者： u.k.Tarai P.s.Robi sukhomay Pal Department of Mechanical Engineering IIT GuwahatiGuwahati 781039India

A new Ni–Cr–si–B–Fe fi ller material is prepared for transient liquid-phase(TLP)bonding of Inconel 718 superalloy by mechanical alloying *** melting temperature range of the fi ller material and its activation energy of melting are determined by diff erential scanning calorimetry *** activation energy and melting temperature of the alloy powder decrease with increasing milling *** 718 alloy was joined via TLP by using the newly developed fi ller *** eff ect of TLP bonding temperature and time on microstructural evolution and mechanical properties of the joint was *** distinct microstructural regions were observed in the bonding area:isothermal solidifi cation zone consisting of a single-phase solid solution,diff usion aff ected zone consisting of extensive diff usion-induced precipitates of metallic boride,and unaff ected base *** ultimate shear strength and microhardness of the TLP-bonded joint increase with bonding time and temperature.

关键词： Transient liquid-phase(TLP)bonding kissinger plot Mechanical alloying Inconel 718

Ocean ecosystem discrete time dynamics generated by l-Vol terra operators

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International Journal of Biomathematics 2019年第2期12卷 77-100页

作者： u.A.Rozikov s.k.shoyimardonov Institute of Mathematics 81Mirzo Ulug'bek Str.100125TashkentUzbekistan Department of Higher Mathematics Tashkent university of Information Technologies(Named After)Muhammad al-khwarizmi TashkentUzbekistan

We consider a discrete-time dynamical system generated by a nonlinear operator(with four real parameters a,b,c,d)of ocean *** find conditions on the parameters under which the operator is reduced to a l-Volterra quadratic stochastic operator mapping two-dimensional simplex to *** show that if cd(c+d)=0,then(under some conditions on a,b)this l-Volterra operator may have up to three or a countable set of fixed points;if cd(c+d)≠0,then the operator has up to three fixed *** on the parameters,the fixed points may be attracting,repelling or saddle *** limit behaviors of trajectories of the dynamical system are *** is shown that independently on values of parameters and on initial(starting)point,all trajectories ***,the operator(dynamical system)is *** give some biological interpretations of our results.

关键词： Quadratic stochastic operator Volterra operator l-Volterra operator ecosystem modeling

Leslie’s prey–predator model in discrete time

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International Journal of Biomathematics 2020年第6期13卷 231-255页

作者： u.A.Rozikov s.k.shoyimardonov V.I.Romanovskiy Institute of Mathematics 81 Mitzo Ulug'bek Street 100125 TashkentUzbekistan Department of Higher Mathematics Tashkent university of Information Technologies Named After Muhammad Al-khwarizmi Tashkent Uzbekistan

We consider the Leslie’s prey–predator model with discrete *** model is given by a nonlinear evolution operator depending on five *** show that this operator has two fixed points and define type of each fixed point depending on the *** two invariant sets of the evolution operator,we study the dynamical systems generated by the operator on each invariant *** on the parameters,we classify the dynamics between a predator and a prey of the Leslie’s model.

关键词： Population Leslie model fixed points prey-predator discrete time

study of residual stresses and distortions from the Ti6Al4V based thinwalled geometries built using LPBF process

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Defence Technology（防务技术） 2023年第10期28卷 33-41页

作者： Jagatheeshkumar s Raguraman M siva Prasad AVs Nagesha B k chandrasekhar u Indian Institute of Information Technology Design and Manufacturing KancheepuramChennai 600127India Gas Turbine Research Establishment DRDOBengaluru 560093India Wipro3D Bengaluru560058India

The current paper focuses on the prediction of residual stresses and distortions in the Laser Powder Bed Fusion(LPBF)built Ti6Al4V thin-walled geometries using Ansys Additive Print(AAP)software which employs a layer-by-layer accumulation of inherent strain to calculate the *** and anisotropic strain scaling factors were calibrated initially within the APP software for the Ti6Al4V based single cantilever beam ***,the numerical simulations were performed in APP software and computed the residual stresses and distortions for the varied process parameters including laser power,scan speed and hatch distance while maintaining the layer thickness constant for all the design *** numerical predictions were compared;they were found to match reasonably well with the XRD measurements within the calibrated regime.

关键词： Ti6Al4V Thin-walled geometry Residual stress Inherent strain XRD Ansys additive print

Influence of an irradiation of a liquid phase by nanosecond electromagnetic impulses (NEMI) on properties of metals and alloys

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Rare Metals 2007年第S1期26卷 14-19页

作者： ri E H ri Hosen DOROFEEV s V kuHARENkO E B Department of Foundry and Process Metallurgy Metrology and Material Inspection LaboratoryPacific National University

The results of research on influence of an irradiation of a liquid phase by nanosecond electromagnetic impulses(NEMI) on processes of crystallization and structurization,physicomechanical and operational properties of... 详细信息

关键词： generator NEMI nanosecond electromagnetic impulses corrosion resistant heat resistance

EFFECTs OF MODIFICATION OF THE CARBIDE CHARACTErisTICs THROuGH GRAIN BOuNDARY sERRATION ON CREEP-FATIGuE LIFE IN AusTENITIC sTAINLEss sTEELs

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Acta Metallurgica sinica(English Letters) 2004年第5期17卷 632-638页

作者： k.J.kim H.u.Hong k.s.Min s.W.Nam Dept. of Materials science and Engineering Korea Advanced Institute of Science and Technology 373-1 Guseong-dong Yuseong-gu Deajeon 305-701 KoreaPosco Technical Research Laboratory #1 Koedong-dong Nam-gu Pohang 790-300 KoreaProcess Solution Development Team 1 LCD R&D Center AMLCD Division Device Solution Network Samsung Electronics Co. LTD.San 24 Nongseo-ri Giheung-eup Yongin Gyeonggi-do 449-771 KoreaDept. of Materials Science and Engineering Korea Advanced Institute of Science and Technology 373-1 Guseong-dong Yuseong-gu Deajeon 305-701 Korea

Modification of the carbide characteristics through the grain boundary serration is investigated, using an AIsI 316 and 304 stainless steels. In both steels, triangular carbides were observed at straight grain boundaries while planar carbides were observed at the serrated grain boundaries. The serrated grain boundary energy is observed to be much lower than that of the straight one. Therefore, the carbide morphology is found to be changed from triangular to planar along the serrated boundary to reduce the interfacial energy between the carbide and the matrix. The creep-fatigue properties of these steels at 873k have been investigated. The creep-fatigue life of the sample with planar carbide at the serrated grain boundary was found to be much longer than that with triangular carbide at the straight one. These results imply that the planar carbides with lower interfacial energy have higher cavitation resistance, resulting in the retardation of cavity nucleation and growth to increase creep-fatigue life.

关键词： cavity nucleation factor grain boundary serration carbide morphology austenitic stainless steel grain boundary cavitation

The Blood Flow of Prandtl Fluid Through a Tapered stenosed Arteries in Permeable Walls with Magnetic Field

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Communications in Theoretical Physics 2015年第3期63卷 353-358页

作者： R.Ellahi s.u.Rahman s.Nadeem k.Vafai Department of Mechanical Engineering University of California Riverside Department of Mathematics and statistics Faculty of Basic Applied sciences International Islamic University Department of Mechatronics University of Engineering and Technology TexilaChakwal Campus Department of Mathematics Quaid-i-Azam University

This Communication deals with the blood flow of Prandtl fluid through a tapered stenosed arteries having permeable *** governing equations of two-dimensional Prandtl fluid model are modelled in cylindrical *** highly nonlinear equations are simplified with the help of non-dimensional variables under the assumption of mild *** solution of reduced nonlinear equation subject to boundary condition of porous walls having the effects of Darcy's number and slip parameter are computed analytically with the help of perturbation *** of emerging parameters such as impedance A,slip parameter a,stenosis height 6,magnetic parameter and stress component srz on velocity are illustrated *** streamlines have also been presented to discuss the trapping bolus discipline.

关键词： Prandtl fluid magnetic field blood flow tapered stenosed arteries permeable walls analytical solutions