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HYERS—ULAM—RASSIAS STABILITY OF QUADRATIc FUNcTIONAL EQUATIONS IN BANAcH MODULES OVER A c^＊—ALGEBRA

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chinese Annals of Mathematics,Series B 2003年第2期24卷 261-266页

作者： c. PARK j. PARK j. SHIN Department of Mathematics Chungnam National University DaeJeon 305-764 South Korea.Department of Mathematics Chungnam National University DaeJeon 305-764 South Korea.Department of Mathematics Chungnam National University DaeJeon 305-764 South Korea.

The authors prove the Hyers-Ulam-Rassias stability of the quadratic mapping in Banachmodules over a unital c*-algebra, and prove the Hyers-Ulam-Rassias stability of the quadraticmapping in Banach modules over a unital... 详细信息

关键词： Stability B-quadratic Functional equation Banach module over Banach algebra

FINITELY GENERATED cOMMUTATIVE ARcHIMEDEAN SEMIGROUPS

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Acta Mathematica Scientia 2003年第4期23卷 503-511页

作者： j.c.Rosales j.I.García-García Departamento de Algebra Universidad de Granada E-18071 Granada EspanaDepartamento de Algebra Universidad de Granada E-18071 Granada Espana

In this work commutative Archimedean finitely generated semigroups axe characterized in terms of ideal extensions.

关键词： commutative semigroups Archimedean

Site Selective Excitation and Energy Transfer in LiKGdF_5 crystal co-doped with Er^(3+) and Tb (3+)

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journal of Rare Earths 2004年第1期22卷 22-26页

作者：尹民 Khaidukov N M Krupa j c Structure Research Laboratory Kurnakov Institute of General and Inorganic chemistry Institut de Physique Nucléaire

crystals of LiKGdF 5∶Er 3+, Tb 3+ grown by the hydrothermal synthesis technique with concentrations of 2% and 0.4% were analysed. By using site selective excitation measured at low temperature, luminescence and excitation spectra from Er 3+ and Tb 3+ ions embedded in LiKGdF 5 were clearly separated. The lifetimes of the emitting levels 4S 3/2 of Er 3+ and 5D 4 of Tb 3+ were also determined. Following the site selective spectroscopy study, the dominant energy transfer process from Tb 3+ to Er 3+ in the crystal was then investigated via transient experiments.

关键词： optics condensed matter physics energy transfer luminescence LiKGdF 5∶Er3+, Tb3+ rare earths

One-step multi-compositional oxidation of YSi alloy:Experiments and ab initio computation

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journal of Materials Science & Technology 2023年第27期158卷 253-262页

作者： W.j.Wang j.c.Luo L.chen G.j.Yang State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an jiaotong University Suzhou Institute Suzhou 215123China

YSi alloy is a promising candidate as oxidation resistant coatings for both the bond coat of environmental barrier coatings(EBcs)and anti-ablation coatings at a high temperature of∼1300℃.In this study,a one-step multi-compositional oxidation by rapid heating oxidation mode is proposed to reduce the oxidation rate by 3.6 times compared to conventional slow heating oxidation *** show that preferentially formed Y_(2)O_(3) oxide initiates a multi-step oxidation,produces a cracking and porous oxides,and thereby resulting in a fast oxidation with *** one-step multi-compositional oxidation with a compact and dense Y_(2)Si_(2)O_(7)scale contributes to the much better oxidation resistance for rapid heating oxidation mode of YSi *** stable formation of Y_(2)Si_(2)O_(7)scale is comprehensively understood by the energy barrier,charge density and electronic level based on density functional *** study demonstrates a promising application of YSi alloy by rapid heating oxidation mode.

关键词： YSi alloy One-step oxidation Multi-compositional scale Y_(2)Si_(2)O_(7) Energy barrier

Influence of texture and microstructure on mechanical properties of high-strength wrought magnesium alloy AZ80

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中国有色金属学会会刊：英文版 2006年第A3期16卷 1754-1757页

作者：张平 j.LINDEMANN c.LEYENS National Engineering Research center of Light Alloy Net Forming Shanghai Jiao Tong UniversityShanghai 200030China chair of Physical Metallurgy and Materials Technology Technical University of Brandenburg at CottbusGermany

Monotonic (tensile and compressive) and high cycle fatigue properties of the forged magnesium alloy AZ80 were investigated by using specimens with load axis parallel to longitude (L) or transverse (T) direction. A pronounced directional anisotropy in monotonic tests was observed in AZ80, i.e. the yield stress in T-direction is significantly lower than that in L direction. However, the directional anisotropy is absent in fatigue, fatigue strengths in both L- and T-directions are essentially equal. The absence of directional anisotropy in fatigue is possibly associated with the microstructure of AZ80. A homogeneous single phase structure probably alleviates the directional anisotropy of fatigue properties of the wrought magnesium alloy.

关键词：镁合金机械性能强度微观结构

Electroosmotic oscillatory flow of micropolar fluid in microchannels:application to dynamics of blood flow in microfluidic devices

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Applied Mathematics and Mechanics(English Edition) 2014年第6期35卷 749-766页

作者： j.c.MISRA S.cHANDRA G.c.SHIT P.K.KUNDU Department of Mathematics Institute of Technical Education and ResearchSiksha O Anusandhan University Department of Mathematics Jadavpur University

The electroosmotic flow of a micropolar fluid in a microchannel bounded by two parallel porous plates undergoing periodic vibration is studied. The equations for conservation of linear and angular momentums and Gauss＇s law of charge distribution are solved within the framework of the Debye-Hückel approximation. The fluid velocity and microrotation are assumed to depend linearly on the Reynolds number. The study shows that the amplitude of microrotation is highly sensitive to the changes in the magnitude of the suction velocity and the width of the microchannel. An increase in the micropolar parameter gives rise to a decrease in the amplitude of microrotation. Numerical estimates reveal that the microrotation of the suspended microelements in blood also plays an important role in controlling the electro-osmotically actuated flow dynamics in microbio-fluidic devices.

关键词： blood flow electrohydrodynamic effect microfluidics channel flow

Electro-osmotic flow of a second-grade fluid in a porous microchannel subject to an Ac electric field

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journal of Hydrodynamics 2013年第2期25卷 309-316页

作者： MISRA j. c. cHANDRA S. Department of Mathematics Institute of Technical Education and Research Siksha O Anusandhan University Department of Physics Sabang S. K. Mahavidyalaya Vidyasagar University

Studies on electro-osmotic flows of various types of fluids in microchannel are of great importance owing to their multifold applications in the transport of liquids, particularly when the ionized liquid flows with respect to a charged surface in the presence of an external electric field. In the case of viscoelastic fluids, the volumetric flow rate differs significantly from that of Newtonian fluids, even when the flow takes place under the same pressure gradient and the same electric field. With this end in view, this paper is devoted to a study concerning the flow pattern of an electro-osmotic flow in a porous microchannel, which is under the action of an alternating electric field. The influence of various rheological and electro-osmotic parameters, e.g., the Reynolds number, Debye-Huckel parameter, shape factor and fluid viscoelasticity on the kinematics of the fluid, has been investigated for a secondgrade viscoelastic fluid. The problem is first treated by using analytical methods, but the quantitative estimates are obtained numerically with the help of the software MATHEMATIcA. The results presented here are applicable to the cases where the channel height is much greater than the thickness of the electrical double layer comprising the Stern and diffuse layers. The study reveals that a larger value of the Debye-Huckel parameter creates sharper profile near the wall and also that the velocity of electro-osmotic flow increases as the permeability of the porous microchannel is enhanced. The study further shows that the electro-osmotic flow dominates at lower values of Reynolds number. The results presented here will be quite useful to validate the observations of experimental investigations on the characteristics of electro-osmotic flows and also the results of complex numerical models that are necessary to deal with more realistic situations, where electro-osmotic flows come into the picture, as in blood flow in the micro-circulatory system subject to an elect

关键词： electrical double layer Debye length second-grade fluid Ionic energy

Visualising data distributions with kernel density estimation and reduced chi-squared statistic

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Geoscience Frontiers 2017年第6期8卷 1247-1252页

作者： c.j.Spencer c.Yakymchuk M.Ghaznavi Earth Dynamics Research Group The Institute of Geoscience ResearchDepartment of Applied GeologyCurtin UniversityPerthAustralia Department of Earth and Environmental Sciences University of WaterlooWaterlooCanada David R.cheriton School of computer Science University of WaterlooWaterlooCanada

The application of frequency distribution statistics to data provides objective means to assess the nature of the data distribution and viability of numerical models that are used to visualize and interpret *** commonly used tools are the kernel density estimation and reduced chi-squared statistic used in combination with a weighted *** to the wide applicability of these tools,we present a java-based computer application called KDX to facilitate the visualization of data and the utilization of these numerical tools.

关键词： Data visualisation Kernel density estimation Reduced chi-squared statistic Mean square weighted deviation Geostatistics

A DIREcT SEARcH FRAME-BASED cONjUGATE GRADIENTS METHOD

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journal of computational Mathematics 2004年第4期22卷 489-500页

作者： I.D.coope c.j.Price DepartmentofMathematicsandStatistics UniversityofCanterburyPrivateBag4800ChristchurchNewZealand

A derivative-free frame-based conjugate gradients algorithm is presented. convergence is shown for c^1 functions, and this is verified in numerical trials. The algorithm is tested on a variety of low dimensional problems, some of which are ill-conditioned, and is also tested on problems of high dimension. Numerical results show that the algorithm is effective on both classes of problems. The results are compared with those from a discrete quasiNewton method, showing that the conjugate gradients algorithm is competitive. The algorithm exhibits the conjugate gradients speed-up on problems for which the Hessian at the solution has repeated or clustered eigenvalues. The algorithm is easily parallelizable.

关键词： conjugate gradients Derivative-free Frame-based methods Numerical results