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Artificial neural network approach for rheological characteristics of coal-water slurry using microwave pre-treatment

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International Journal of Mining Science and Technology 2017年第2期27卷 379-386页

作者： b.K.Sahoo S.De b.C.Meikap Department of Chemical Engineering Indian Institute of Technology Research and Development Centre for Iron and Steel Steel Authority of India Limited Chemical Engineering School of Engineering Howard College University of Kwazulu-Natal

Detailed experimental investigations were carried out for microwave pre-treatment of high ash Indian coal at high power level(900 W) in microwave oven. The microwave exposure times were fixed at60 s and 120 s. A rheology characteristic for microwave pre-treatment of coal-water slurry(CWS) was performed in an online bohlin viscometer. The non-Newtonian character of the slurry follows the rheological model of Ostwald de Waele. The values of n and k vary from 0.31 to 0.64 and 0.19 to 0.81 Pa·sn,respectively. This paper presents an artificial neural network(ANN) model to predict the effects of operational parameters on apparent viscosity of CWS. A 4-2-1 topology with Levenberg-Marquardt training algorithm(trainlm) was selected as the controlled ANN. Mean squared error(MSE) of 0.002 and coefficient of multiple determinations(R^2) of 0.99 were obtained for the outperforming model. The promising values of correlation coefficient further confirm the robustness and satisfactory performance of the proposed ANN model.

关键词： Microwave pre-treatment Coal-water slurry Apparent viscosity Artificial neural network back propagation algorithm

Design and optimization of cantilevered magnetostrictive film-substrate microactuator

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Science China(Technological Sciences) 2007年第5期50卷 683-693页

作者： b.Narsu Institute of Science and Technology Inner Mongolia University

The exact solution for the bending problem of a free-end point loaded film- substrate cantilever with arbitrary film-to-substrate thickness ratio is obtained by using the basic mechanical equilibrium equation. And then the problem of design and optimization for microactuator buildup of film-substrate cantilever is discussed by taking into account the effect of geometrical and physical parameters of the cantilever components. Furthermore, the optimal condition for actuator application is presented and some theoretical problems are clarified. The results show that, in general, the greater the film-to-substrate thickness ratio, the higher the ability of taking load, namely the larger the exerted force of the cantilever when the thickness of substrate is kept constant. When the total thickness of the cantilever is kept constant, however, the free-end exerted force will experience a maximum and this maximum value of the exerted force will decrease with the increasing film-to-sub- strate stiffness ratio. Meanwhile, the optimal thickness ratio corresponding to this maximum exerted force also decreases with the increasing stiffness ratio. Whether for the cases of fixed substrate or fixed total thickness, the influence of Poisson’s ratio of two cantilever components on the exerted force is remarkable, and should not be neglected.

关键词： magnetic film-substrate system, cantilever, deflection, actuator, exerted force

Additive Mappings Preserving Rank-one Idempotents

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Acta Mathematica Sinica,English Series 2005年第6期21卷 1399-1406页

作者： b. KUZMA Institute of Mathematics Physics and Mechanics Department of Mathematics Jadranska 19 1000 Ljubljana Slovcnia

A complete characterization of additive mappings φ ： b（X）→b（Y）, which map rank-one idempotents to themselves or to zero, is given.

关键词： Additive preservers Idempotents Rank

Influence of magnetic field on wave propagation at liquid-microstretch solid interface

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Applied Mathematics and Mechanics(English Edition) 2011年第5期32卷 595-602页

作者： b.SINGH Department of Mathematics Post Graduate Government College

The reflection and refraction of a longitudinal wave at an interface between a perfectly conducting nonviscous liquid half-space and a perfectly conducting microstretch elastic solid half-space are studied. The appropriate solutions to the governing equations are obtained in both the half-spaces satisfying the required boundary conditions at the interface to obtain a system of five non-homogeneous equations in the amplitude ratios of various reflected and transmitted waves. The system is solved by a Fortran program of the Gauss elimination method for a particular example of an interface between water and aluminum-epoxy composite. Numerical values of the amplitude ratios are computed for a certain range of the incidence angle both in the presence and absence of an impressed transverse magnetic field. The effects of the presence of the transverse magnetic field on the amplitude ratios of various reflected and transmitted waves are shown graphically.

关键词： microstretch wave propagation reflection and transmission magnetic field

Orbits of Ten Visual binary Stars

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Chinese Journal of Astronomy and Astrophysics 2007年第3期7卷 415-420页

作者： b. Novakovi Astronomical Observatory Volgina 7 11160 Belgrade 74 Serbia

We present the orbits of ten visual binary stars： WDS 01015＋6922, WDS 01424- 0645, WDS 01461 ＋6349, WDS 04374-0951, WDS 04478＋5318, WDS 05255-0033, WDS 05491＋6248, WDS 06404＋4058, WDS 07479-1212, and WDS 18384＋... 详细信息

关键词： binaries visual

Suitability of lost cores in rheocasting 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 948-953页

作者： H.MICHELS M.büNCK A.büHRIG-POLACZEK Giesserei-Institut RWTH Aachen Intzestraeβ5Aachen 52072Germany

When treated in pressure die casting processes the semi-solid aluminum alloys demand resilient cores which can bear the stress occurring during filling and the final pressure *** design of permanent cores is highly restricted in order to maintain *** cores provide the possibility of complex,undercut geometrical shapes which is mandatory for a variety of casting ***,eligible materials which show appropriate resilience and proper decomposition properties at the same time,and in the upper echelon of cost-effectiveness,are seldom *** the semi-solid process suited between HPDC and GDC regarding the core stress,several common and economically efficient lost core systems could be used.A selection of potentially suitable materials was identified and *** range of testing comprises widespread sand core-systems(amin-pur-coldbox and CO2-water-glass) as well as materials less commonly used,namely salt,plastic and *** types of conditioning are applied to enhance the surface *** mechanical properties of the sand cores are enhanced by different heat treatment methods during *** cores are tested producing a research component cast on a HPDC machine with semi-solid A356 slurry fabricated in the cooling channel *** cast component was analyzed regarding shape stability,core removability and surface as well as the structure *** results show the importance of the surface conditioning for the sand-cores while salt and zinc produce good parts comparable to the reference steel core quality.

关键词： aluminum semi-solid rheocasting cooling channel lost core sand salt zinc plastic

Impact analysis of compressor rotor blades of an aircraft engine

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 505-514页

作者： Y b SUDHIR SASTRY b G KIROS F HAILU R bUDARAPU Department of Aeronautical Engineering Institute of Aeronautical EngineeringDundigalHyderabad 500043India Department of Aeronautical Engineering College of EngineeringDefense UniversityBishoftu 1041Ethiopia School of Mechanical Sciences Indian Institute of Technology BhubaneswarBhubaneswar 752050India

Frequent failures due to foreign particle impacts are observed in compressor blades of the interceptor fighter MIG-23 aircraft engines in the Ethiopian air force,supplied by the Dejen Aviation *** this paper,we made an attempt to identify the causes of failure and hence recommend the suitable materials to withstand the foreign particle *** and stress analysis of one of the recently failed MIG-23 gas turbine compressor blades made up of the following Aluminum based alloys:6061-T6,7075-T6,and 2024-T4,has been performed,apart from the impact analysis of the rotor blades hit by a granite *** numerical results are correlated to the practical *** on the modal,stress and impact analysis and the material properties of the three considered alloys,alloy 7075-T6 has been recommended as the blade material.

关键词： axial flow compressor rotor and stator blades aircraft engine stress and impact analysis aluminum alloys

D^0~0 mixing and other recent charm results from bAbAR

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Chinese Physics C 2010年第6期34卷 780-787页

作者： b.Meadows University of Cincinnati Department of Physics

Studies in which bAbAR data have shown evidence for mixing in the neutral charm meson system are presented. A new measurement of the lifetime difference parameter ycp = （1.16±0.22±0.18）% is described. Results are also presented from a systematic study of DK and D＊K invariant mass distributions from a 470 fb^-1 sample of asymmetric e^＋e^- interactions recorded by the bAbAR detector at the PEP-Ⅱ storage rings. A new charmed-strange meson has been observed with mass [3044 ± 8stat （-5^＋30 ）syst] MeV/c^2 and width [239± 35stat （-42^＋46）syst]MeV/c^2.

关键词： mixing oscillations charm meson spectroscopy

T-duality as permutation of coordinates in double space

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Chinese Physics C 2017年第5期41卷 16-25页

作者： b.Sazdovic Institute of Physics University of Belgrade 11001 Belgrade P.O.Box 57 Serbia

We introduce the 2D dimensional double space with the coordinates Z^M=（x~μ,y_μ）,whose components are the coordinates of initial space x~μ and its T-dual y_μ.We shall show that in this extended space the T-duality transformations can be realized simply by exchanging the places of some coordinates x^a,along which we want to perform T-duality,and the corresponding dual coordinates y_*** such an approach it is evident that T-duality leads to the physically equivalent theory and that a complete set of T-duality transformations forms a subgroup of the 2D permutation ***,in double space we are able to represent the backgrounds of all T-dual theories in a unified manner.

关键词： duality coordinates subgroup permutation unified inverse arbitrary connect exchanging physically