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journal of computational Mathematics 2015年第2期33卷 191-208页

作者： c. Brennecke A. Linke c. Merdon j. Schoberl Eidgen6ssische Technische Hochschule Ziirich Departement Mathematik Riimistr. 101 8092 Ziirich Switzerland Weierstrass Institute for Applied Analysis and Stochastics Mohrenstr. 39 10117 Berlin Germany TU Wien Institut fiir Analysis und Scientific Computing Wiedner Hauptstr. 8-10//1011040 Wien Austria

Nearly all inf-sup stable mixed finite elements for the incompressible Stokes equations relax the divergence constraint. The price to pay is that a priori estimates for the ve- locity error become pressure-dependent, while divergence-free mixed finite elements de- liver pressure-independent estimates. A recently introduced new variational crime using lowest-order Raviart-Thomas velocity reconstructions delivers a much more robust modi- fied crouzeix-Raviart element, obeying an optimal pressure-independent discrete H1 ve- locity estimate. Refining this approach, a more sophisticated variational crime employing the lowest-order BDM element is proposed, which also allows proving an optimal pressure- independent L2 velocity error. Numerical examples confirm the analysis and demonstrate the improved robustness in the Navier-Stokes case.

关键词： Variational crime crouzeix-Raviart finite element Divergence-free mixed me-thod Incompressible Navier-Stokes equations A priori error estimates.

Assessment of Man-made and Natural Hazards in the Surroundings of Hydropower Projects under construction in the Beas Valley of Northwestern Himalaya

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journal of Mountain Science 2007年第3期4卷 221-236页

作者： Sanjeev Sharma jagdish c. Kuniyal j. c. Sharma G.B. Pant Institute of Himalayan Environment & Development Himachal UnitMohal-Kullu 175 126Himachal Pradesh India Department of Geography Himachal Pradesh University

Mountain ecosystem, on the earth, has plenty of natural resources. In Himachal Pradesh all the rivers are snowfed and therefore rich in water resources. These resources have been supporting enough for the generation of electricity through introducing hydropower projects since the last decade However, every developmental activity has its own negative impacts on the surrounding environment. Due to the fragile nature of topography and delicacy of ecology of the Himalaya, it results in lot of disturbances because of high degree of human interferences like construction of major hydropower projects. The increased extent of geological hazards, such as landslides, rock fall and soil erosion, have mainly due to alike developmental interventions in the natural ecosystem. So understanding and analysing such impacts of the hydropower projects have mainly been on the environment in various forms but natural hazards have been frequent ones. The present study, therefore, focuses mainly on the Parbati Stage II （800 MW） and the Parbati Stage III （520 MW） hydropower projects; both of which fall within the Kullu district of Himachal Pradesh. Based on the perception survey of the local communities, the existing land use pattern, status of total acquired land of the residents by hydropower projects, frequent natural hazards and resultant loss to the local communities due to upcoming construction of hydropower projects surrounding to the Parbati Stage II and III have been analysed in the paper. Also, the preventive measures to mitigate these adverse impacts have been suggested to strengthen these projects in eco-friendly manner in the mountain context.

关键词： Hydropower project under construction local community hazard preventive measure environment northwestern Indian Himalaya

Peristaltic transport of rheological fluid:model for movement of food bolus through esophagus

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Applied Mathematics and Mechanics(English Edition) 2012年第3期33卷 315-332页

作者： j.c.MISRA S.MAITI Department of Mathematics Institute of Technical Education and ResearchSiksha 'O' Anusandhan UniversityBhubaneswar 751030India School of Medical Science and Technology & center for Theoretical Studies Indian Institute of TechnologyKharagpur 721302India

Fluid mechanical peristaltic transport through esophagus is studied in the paper. A mathematical model has been developed to study the peristaltic transport of a rheological fluid for arbitrary wave shapes and tube lengths. The Ostwald-de Waele power law of a viscous fluid is considered here to depict the non-Newtonian behaviour of the fluid. The model is formulated and analyzed specifically to explore some important information concerning the movement of food bolus through esophagus. The analysis is carried out by using the lubrication theory. The study is particularly suitable for the cases where the Reynolds number is small. The esophagus is treated as a circular tube through which the transport of food bolus takes place by periodic contraction of the esophageal wall. Variation of different variables concerned with the transport phenomena such as pressure, flow velocities, particle trajectory, and reflux is investigated for a single wave as well as a train of periodic peristaltic waves. The locally variable pressure is seen to be highly sensitive to the flow index ＂n＂. The study clearly shows that continuous fluid transport for Newtonian/rheological fluids by wave train propagation is more effective than widely spaced single wave propagation in the case of peristaltic movement of food bolus in the esophagus.

关键词： non-Newtonian fluid food bolus esophagus peristaltic transport flow reversal single wave wave train particle trajectory

A three-dimensional model for the transportation of Fe and Mn in Arha Reservoir

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journal of Environmental Sciences 2000年第2期12卷 36-46页

作者： Xiao-hong, c. Brimicombe, A.j. Department of Geography Zhongshan University Guangzhou 510275 China

coupling with a three dimensional (3D) hydrodynamic model and a suspended solids model, a 3D model for the transport of Fe and Mn in Arha Reservoir, china, was developed. The 3D velocity fields for the flood season are computed to drive the 3D model of Fe and Mn in which the processes of advection, diffusion, redox, sorption, desorption, deposition, and re suspension are included. The model has been calibrated by matching observed fluid, suspended solids, and total concentrations of Fe and Mn in the water column and in the sediment, successively. The model simulated both horizontal and vertical gradients of Fe and Mn in Arha Reservoir. It was found that Fe and especially Mn stratify in accordance with the stratification of DO during summer. The redox cycles across the water sediment interface has a principal role in the rise of Fe and Mn concentrations in the overlying water. It was also found that Fe and Mn loadings from the tributaries have a carryover effect on the water quality through a secondary contamination in the reservoir.

关键词： three dimensional model Fe Mn transport flow field Arha Reservoir cLc number: X1 Document code: A

EFFEcTS OF La ON STRUcTURE AND PROPERTIES OF HEAVY RAIL STEEL

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Acta Metallurgica Sinica(English Letters) 2005年第6期18卷 701-706页

作者： c.j. Liu M.F. jiang Y.S. Wang j.j. chen c.L. Li Northeastern University Shenyang 110004 China Baotou Iron and Steel Group Gorporation Baotou 014010 Ghina

The mechanisms of La in heavy rail steel were studied by means of experimental measurements, microstructure observation and theoretical analysis in the present work. For heavy rail steel, the state and the content of La were measured, and the mechanisms and the effects of La on sulfide inclusions, microstracture and properties of steel were determined. Strip-like sulfides disappear in heavy rail steel with La/（O＋S）〉3.50, which is shown that the metallurgical function of modifying sulfide inclusions has been achieved by La. La can fine the grain size of the austenite in heavy rail steel. Under the experimental condition, the plasticity and the impacting toughness of heavy rail steel with 0.005wt% La can evidently be improved.

关键词： rare earth heavy rail steel microscopic structure sulfide inclusion,property

Entropy, Fisher Information and Variance with Frost-Musulin Potenial

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communications in Theoretical Physics 2016年第9期65卷 269-274页

作者： j.O.A.Idiodi c.A.Onate Physics Department University of Benin

This study presents the Shannon and Renyi information entropy for both position and momentum space and the Fisher information for the position-dependent mass Schr¨odinger equation with the Frost-Musulin potential. The analysis of the quantum mechanical probability has been obtained via the Fisher information. The variance information of this potential is equally computed. This controls both the chemical properties and physical properties of some of the molecular systems. We have observed the behaviour of the Shannon entropy. Renyi entropy, Fisher information and variance with the quantum number n respectively.

关键词： Fisher information Shannon entropy position-dependent mass

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