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convergence Analysis of Iterative Sequences for a Pair of Mappings in Banach Spaces

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Acta Mathematica Sinica,English Series 2008年第3期24卷 463-470页

作者： Liu chuan ZENG N.c.WONG j.c.YAO Department of Mathematics Shanghai Normal University Shanghai 200234 P. R. China Department of Applied Mathematics National Sun Yat-Sen University Kaohsiung Taiwan 80424

Let c be a nonempty closed convex subset of a real Banach space E. Let S ： c→ c be a quasi-nonexpansive mapping, let T ： c→c be an asymptotically demicontractive and uniformly Lipschitzian mapping, and let F ：= {x ∈c ： Sx = x and Tx = x}≠Ф Let {xn}n≥0 be the sequence generated irom an arbitrary x0∈cby xn＋i=（1-cn）Sxn＋cnT^nxn, n≥*** prove the necessary and sufficient conditions for the strong convergence of the iterative sequence {xn} to an element of F. These extend and improve the recent results of Moore and Nnoli.

关键词： quasi-nonexpansive mapping asymptotically demicontractive type mapping iterative sequence convergence analysis

Development of Lattice Boltzmann Flux Solver for Simulation of Incompressible Flows

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Advances in Applied Mathematics and Mechanics 2014年第4期6卷 436-460页

作者： c.Shu Y.Wang c.j.Teo j.Wu Department of Mechanical Engineering National University of Singapore10 Kent Ridge CrescentSingapore 119260 Department of Aerodynamics College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China

A lattice Boltzmann flux solver(LBFS)is presented in this work for simulation of incompressible viscous and inviscid *** new solver is based on chapman-Enskog expansion analysis,which is the bridge to link Navier-Stokes(N-S)equations and lattice Boltzmann equation(LBE).The macroscopic differential equations are discretized by the finite volume method,where the flux at the cell interface is evaluated by local reconstruction of lattice Boltzmann solution from macroscopic flow variables at cell *** new solver removes the drawbacks of conventional lattice Boltzmann method such as limitation to uniform mesh,tie-up of mesh spacing and time interval,limitation to viscous *** is validated by its application to simulate the viscous decaying vortex flow,the driven cavity flow,the viscous flow past a circular cylinder,and the inviscid flow past a circular *** obtained numerical results compare very well with available data in the literature,which show that LBFS has the second order of accuracy in space,and can be well applied to viscous and inviscid flow problems with non-uniform mesh and curved boundary.

关键词： chapman-Enskog analysis flux solver incompressible flow Navier-Stokes equation lattice Boltzmann equation

Fabrication and Properties of SiB6-B4c with Phenolic Resin as a carbon Source

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journal of Materials Science & Technology 2008年第1期24卷 102-104页

作者： G. c.Hwang j.Matsushita United Graduate School of Science and Engineering Tokai University 1117 Kitakaname Hiratsuka 259-12921 Japan

Si-B-c ceramic composites were synthesized using SiB-6,B-4c,and phenolic resin as a carbon source by pressureless sintering in an Ar ***,the Si-B-c ceramic composites were fabricated to determine their potential for applications as high hardness and high temperature *** X-ray diffraction patterns of sintered bodies of SiB-6-B-4c with carbonized phenolic resin can be seen that SiB-6 and c changed to B-4c and *** this study,it is obtained that carbonized phenolic resin is good addition material as a reaction material comparing to carbon powder at 1683 K for 1 h by pressureless sintering in an Ar atmosphere.

关键词： Silicon boride Boron carbide Phenolic resin

A numerical optimization of high altitude testing facility for wind tunnel experiments

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chinese journal of Aeronautics 2015年第3期28卷 636-648页

作者： j.Bruce Ralphin Rose G.R.jinu c.j.Brindha Department of Aeronautical Engineering Regional Centre of Anna University Department of Mechanical Engineering University College of EngineeringNagercoil Department of Aeronautical Engineering The Raajas Engineering College

Abstract High altitude test facilities are required to test the high area ratio nozzles operating at the upper stages of rocket in the nozzle full flow conditions. It is typically achieved by creating the ambient pressure equal or less than the nozzle exit pressure. On average, air/GN2 is used as active gas for ejector system that is stored in the high pressure cylinders. The wind tunnel facilities are used for conducting aerodynamic simulation experiments at/under various flow velocities and operating conditions. However, constructing both of these facilities require more laboratory space and expensive instruments. Because of this demerit, a novel scheme is implemented for conducting wind tunnel experiments by using the existing infrastructure available in the high altitude testing （HAT） facility. This article presents the details about the methods implemented for suitably modifying the sub-scale HAT facility to conduct wind tunnel experiments. Hence, the design of nozzle for required area ratio A/A＊, realization of test section and the optimized configuration are focused in the present analysis. Specific insights into various rocket models including high thrust cryogenic engines and their holding mechanisms to conduct wind tunnel experiments in the HAT facility are analyzed. A detailed cFD analysis is done to propose this conversion without affecting the existing functional requirements of the HAT facility.

关键词： cFD Enclosed free-jet section Ground testing High altitude testing (HAT)facility Optimization

Ophiolites:Identification and tectonic significance in space and time

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Geoscience Frontiers 2023年第6期14卷 380-385页

作者： Kent c.condie Robert j.Stern Department of Earth&Environmental Science New Mexico Institute of Mining and TechnologySocorroNM 87801USA Geosciences Department University of Texas at DallasRichardsonTX 75080USA

Ophiolites are fragments of oceanic lithosphere that are produced at spreading centers at ocean ridges,back arc basins,or forearcs during subduction initiation,and are key indicators of plate *** it is widely agreed that ophiolites are remnants of oceanic crust and associated depleted mantle preserved in orogens,the recognition of ophiolites and their tectonic significance is still a topic of discussion and *** propose that ophiolites can be recognized in the geologic record by some combination of genetically related pillow basalt,layered gabbro,sheeted dykes,podiform chromite,harzburgite or/and *** igneous rocks have either ocean-ridge basalt or immature oceanic arc basalt chemical *** a scoring system of 1–11 for ophiolite confidence level,scores of8 are considered confident,6–8 probable,andcores6 areconfident ophiolite(score of 8)is the Zunhua ophiolite in eastern china at 2550 Ma,and the oldest well documented sheeted dykes occur in the jormua and Purtuniq ophiolites at 2000–1950 *** do not become geographically widespread until after 900 Ma,and most ophiolites of all ages formed in a forearc(subduction initiation)tectonic *** ophiolite production requires plate tectonics,subduction must have begun at least locally by 2700 Ma but did not become widespread until after 2000 *** abundance of ophiolites after 900 Ma may reflect better preservation of subduction-related ophiolites,or to an increasing global network of interconnected *** frequency peaks in the geologic record partially reflect geographic regions where ophiolites have been extensively studied rather than monitoring the production rate of ophiolites,but the scarcity of>900 Ma ophiolites is probably real.

关键词： Ophiolite Plate tectonics Subduction initiation Forearc Ocean ridge Tectonic setting Supercontinent

Accuracy details in realistic cFD modeling of an industrial centrifugal pump in direct and reverse modes

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journal of Thermal Science 2010年第6期19卷 491-499页

作者： j.c. Páscoa F. j. Silva j.S. Pinheiro D.j. Martins Department of Electromechanical Engineering Center for Aerospace Sciences and Technology University of Beira Interior EFAFLU Bombas e Ventiladores S.A. R. S. Brás 269 Apartado 23 4494-909 Póvoa do Varzim Portugal

Numerical computation of the flowfield inside a pump is herein used as a numerical laboratory, subject to the limitations of modeling assumptions and to experimental verification. A numerical computation of the flow inside a real industrial centrifugal pump is performed that includes a very sophisticated geometry. conversely to other computations, in this test case no simplification of the geometry was introduced. Numerical computations are obtained using Spalart-Allmaras turbulence model. A detailed analysis of the turbulent flowstructure is performed for the design point and two off design conditions. Additional computations were performed in order to compare the numerical and experimental pump characteristics; these were obtained under normalized testing conditions. Further computations are presented for the pump working in reverse turbine mode (PAT). Detailed analyses of the flow allow a comparison of the internal flow losses when the pump is operating in direct and reverse mode. This is also useful to help in the selection of an adequate pump geometry that can work in both modes with best efficiency.

关键词： centrifugal pump impeller turbulence modeling Spalart-Allmaras PAT

Propylthiouracyl-induced severe liver toxicity:An indication for alanine aminotransferase monitoring?

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World journal of Gastroenterology 2006年第38期12卷 6232-6234页

作者： M Benyounes c Sempoux c Daumerie j Rahier AP Geubel Departments of Gastroenterology Endocrinology and Pathology St Luc University Hospital Université Catholique de Louvain Brussels 1200 Belgium

Propylthiouracyl (PTU)-related liver toxicity is likely to oc- cur in about 1% of treated patients. In case of acute or subacute hepatitis, liver failure may occur in about one third. We report two further cases of PTU-induced sub- acute hepatitis, in whom the delay between occurrence of liver damage after the initiation of treatment, the un- derestimation of its severity and the delayed withdrawal of the drug were all likely responsible for liver failure. The high incidence of liver toxicity related to PTU, its potential severity and delayed occurrence after initiation of treatment are in favor of monthly alanine aminotrans- ferase monitoring, at least during the first six months of therapy.

关键词： Hepatitis Drug-induced liver toxicity Propylthiouracil Alanine aminotransferase

Hole Burning in the Fock Space: from Single to Several Holes

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chinese Physics Letters 2001年第11期18卷 1467-1469页

作者： B.Baseia j.M.c.Malbouisson Instituto de Fisica Universidade Federal de Goias74001-970GoianiaGOBrazil Instituto de Fisica Universidade Federal da Bahia40210-340SalvadorBABrazil

In our previous papers we have studied the production of a single hole in the photon number distribution of a field state [Phys. Lett. A 240 (1998) 277;253 (1999) 123]. In this letter we extend the procedure for the c... 详细信息

关键词： letter creation distribution

Stability of steel thixoforming process

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中国有色金属学会会刊：英文版 2010年第S3期20卷 937-942页

作者： j.c.PIERRET A.RASSILI G.VANEETVELD j.LEcOMTE-BEcKERS ThixoUnit ULg Material Sciences UnitDepartment of Aerospace and Mechanical EngineeringUniversity of Liège

To improve the industrialization of the process,the study of a thixoforming line stability was *** thixoforming line is fully automated to optimize the repeatability of the *** of the heating cycle,the slug temperature,the tool temperature and the forming speed were *** each of them,a range of the expected variations in a steady-state process as well as the effects of these variations on the process itself(forming load and parts quality) were *** variations are shown to be *** different tools were used in the *** mathematical simulations were realized on the finite elements code Forge2008with a semi-solid constitutive *** capacity of the model to represent the process stability was *** simulation results are in agreement with the experiment results.

关键词： thixoforming steel high melting point stability robustness process