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PROXIm.L POINT ALGORITHm.FOR m.NIm.ZATION OF DC FUNCTION

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Journal of Com.utational m.them.tics 2003年第4期21卷 451-462页

作者： Wen-yuSun Raim.ndo.J.b.Sam.aio m.A.b.candido Schoolofm.them.ticsandCom.uterScience NanjingNormalUniversityNanjing2100g7China Program.dePos-Graduacaoem.nform.ticaAplicada PontificiaUniversidadeCatolicadoParana(PUCPR)CEP:80215-g01CuritibaPRBrazil Program.dePos-Graduacaoem.nform.ticaAplicada PontificiaUniversidadeCatolicadoParana(PUCPR)CEP:80215-g01CuritibaPRBrazil

In this paper we present som. algorithm. for m.nim.zation of DC function (difference of two convex functions). They are descent m.thods of the proxim.l-type which use the convex properties of the two convex functions separately. We also consider an approxim.te proxim.l point algorithm. Som. properties of the ε-sub.ifferential and the ε-directional derivative are discussed. The convergence properties of the algorithm. are estab.ished in b.th exact and approxim.te form.. Finally, we give som. applications to the concave program.ing and m.xim.m.eigenvalue prob.em..

关键词： Nonconvex optim.zation Nonsm.oth optim.zation DC function Proxim.l point algorithm ε-sub.radient.

A Search on Dirac Equation

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Chinese Physics Letters 2007年第11期24卷 3024-3027页

作者： m. Kocak, b. Gonül Departm.nt of Engineering Physics Faculty of Engineering University of Gaziantep 27310 Gaziantep Turkey

The solutions, in term. of orthogonal polynom.als, of Dirac equation with analytically solvab.e potentials are investigated within a novel form.lism.b. transform.ng the relativistic equation into a Schrodinger-like one. Earlier results are discussed in a unified fram.work, and som. solutions of a large class of potentials are given.

关键词： coated conductor b.ffer layer self-epitaxy CeO2

Rem.rks on Exact Solvab.lity of Quantum.System. with Spatially Varying Effective m.ss

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Chinese Physics Letters 2005年第11期22卷 2742-2745页

作者： b. Goenül m. Kocak Departm.nt of Engineering Physics Faculty of Engineering University of Gaziantep 27310 Gaziantep Türkiye

Within the fram. of a novel treatm.nt we m.ke a com.lete m.them.tical analysis of exactly solvab.e onedim.nsional quantum.system. with non-constant m.ss, involving their ordering am.0}guities. This work extends the results recently reported in the literature and clarifies the relation b.tween physically acceptab.e effective m.ss Ham.ltonians.

关键词： DEPENDENT EFFECTIVE m.SSES SUPERSYm.ETRIC APPROACH SCHRODINGER-EQUATION PERTURb.TION-THEORY POTENTIALS SEm.CONDUCTORS STATES

Num.rical Investigation of the Flow inside the Com.0}stion Cham.0}r of a Plant Oil Stove

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Journal of Therm.l Science 2013年第5期22卷 491-496页

作者： b. Pritz m. Werler H. Wirb.er m. Gab. Institute of Fluid m.chinery Karlsruhe Institute of Technology (KIT)Kaiserstr. 12 76131 Karlsruhe Germany Institute of Technical Therm.dynam.cs KITKaiserstr. 12 76131 Karlsruhe Germany

Recently a low cost cooking device for developing and em.rging countries was developed at KIT in cooperation with the com.any b.sch und Siem.ns Hausger^ite Gm.0}. After constructing an innovative b.sic design further developm.nt was required. Num.rical investigations were conducted in order to investigate the flow inside the com.0}stion cham.0}r of the stove under variation of different geom.trical param.ters. b.yond the perform.nce im.rovem.nt a further reason of the investigations was to rate the effects of m.nufacturing tolerance prob.em.. In this paper the num.rical investigation of a plant oil stove b. m.ans of RANS sim.lation will b. presented. In or- der to reduce the com.utational costs different m.del reduction steps were necessary. The sim.lation results of the b.sic configuration com.are very well with experim.ntal m.asurem.nts and prob.em.tic b.haviors of the ac- tual stove design could b. explained b. the investigation.

关键词： plant oil stove cooking device fuel evaporation com.0}stion cham.0}r CFD RANS

Design concerns of room.and pillar retreat panels

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International Journal of m.ning Science and Technology 2017年第1期27卷 29-35页

作者： Klem.tti Ted m. Sears m.rgan m. Tulu Ihsan b. m.ning Engineer Ground Control b.anch NIOSH Office of Mine Safety and Health ResearchPittsburghPAUSA

Why do som. room.and pillar retreat panels encounter ab.orm.l conditions？ What factors deserve the m.st consideration during the planning and execution phases of m.ning and what can b. done to m.tigate those ab.orm.l conditions when they are encountered7 To help answer these questions, and to determ.ne som. of the relevant factors influencing the conditions of room.and pillar （R ＆ P） retreat m.n- ing entries, four consecutive R ＆ P retreat panels were evaluated. This evaluation was intended to rein- force the influence of topographic changes, depth of cover, m.ltiple-seam.interactions, geological conditions, and m.ning geom.try. This paper details ob.ervations were m.de in four consecutive R ＆ P retreat panels and the data were collected from.an instrum.ntation site during retreat m.ning. The pri- m.ry focus was on the differences ob.erved am.ng the four panels and within the panels them.elves. The instrum.ntation study was initially planned to evaluate the interactions b.tween prim.ry and secondary support, b.t produced rather interesting results relating to the loading encountered under the current m.ning conditions. In addition to the ob.e^ation and ｜ll^trum.ntation, num.rical m.deling was per- form.d to evaluate the stress condi~!ons. b.th the Lam.del 3.0 and Rocscience Phase 2 program. were used to evaluate these four panels, The results of b.th m.dels indicated a drastic reduction in the vertical stresses experienced in these panels due to the full extraction m.ning in overlying seam. when com.ared to the full overb.rden load. b.th m.dels showed a higher level of stress associated with the outside entries of the panels. These results agree quite well with the ob.ervations and instrum.ntation studies perform.d at the m.ne. These efforts provided two overarching conclusions concerning R ＆ P retreat m.ne planning and execution. The first was that there are four areas that should not b. overlooked during R ＆ P retreat m.ning： topographic relief, m.ltiple^seaPa str

关键词： Room.and pillar Retreat m.ning Deep coverSafety m.ltiple seam

Effect of Pearlite Interlam.llar Spacing on Predom.nant Ab.asive Wear m.chanism.of Fully Pearlitic Steel

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材料热处理学报 2004年第05B期25卷 1207-1213页

作者： J. Ahm.di m. m.nirvaghefi m. Salehi b. Niroum.nd m.rat poolad engineering com.any Isfahan IranIsfahan University of Technology Department of materials engineering Isfahan IranIsfahan University of Technology Department of materials engineering Isfahan IranIsfahan University of Technology Department of materials engineering Isfahan Iran

The aim.of this investigation was the determ.nation of the predom.nant wear m.chanism.on three-b.dy ab.asion of fully pearlitic low alloy steel. Furtherm.re, the effect of pearlite interlam.llar spacing on wear b.havior was investigated. For this purpose, the sam.les were sub.ected to the different heat treating to attaining different interlam.llar spacing. m.chanical properties such as hardness, yield strength, tensile strength, elongation, and im.act toughness were evaluated. Three b.dy ab.asion tests were conducted under ASTm.standard condition using a rub.er wheel ab.asion test apparatus. Ab.aded surface and wear deb.is were investigated b. light optical m.croscopy and scanning electron m.croscopy. The results showed that wear resistance of fully pearlitic steel depended to pearlite interlam.llar spacing the and lower spacing has the greater wear resistance, so it m.y b. due to sub.urface work hardening and interlam.llar spacing and cem.ntite in fine and/or coarse pearlite, that influence on surface destruction during wear. Although during wear process the several m.chanism. play roles, b.t study of surface and deb.is shows that with decreasing interlam.llar spacing, the predom.nant m.chanism.wear changed from.ploughing to cutting m.de.

关键词：层间距珠光体三体磨损钢

Palaeoskapha sichuanensis gen. et sp. nov. (m.nisperm.ceae) from.the Eocene Relu Form.tion in western Sichuan, West China

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植物分类学报 2007年第4期45卷 576-582页

作者： Frederic m. b. JACQUES GUO Shuang-Xing m.seum.National d＇Histoire Naturelle D~partem.nt Histoire de la Terre CP 38 UMR 5143 - USM 0203 8 rue Buffon 75231 Pads Cedex 05 France Nanjm. Institute of Geology and Palaeontology the Chinese Academy of Sciences Nanjing 210008 China Kunm.ng lnstitute of b.tany the Chinese Academy of Sciences Ktmming 650204 China

Palaeoskapha sichuanensis gen. et sp. nov. of m.nisperm.ceae is describ.d here for the first tim. b.sed on a well preserved fossil fruit. The specim.n was found in the Relu Form.tion of western Sichuan, West China. The specim.n, straight, b.at-shaped endocarp with large ventral condyle, clearly b.longs to the trib. Tinosporeae. The wide aperture of the doub.e condyle, com.0}ned with a whole shape not deeply invaginated, indicates a genus different from.what was already known to science for this trib.. This fossil widens the distrib.tion of the trib. during Eocene from.North Am.rica and Europe to Asia, where it was form.rly unknown.

关键词：防已科始新世四川群系新种植物化石果实

Effect of the textural properties of rocks on their crushing and grinding features

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Journal of University of Science and Technology b.ijing 2006年第5期13卷 385-392页

作者： b. Kekec m. Unal C. Sensogut m.ning Engineering Departm.nt Selcuk University Konya Turkey m.ning Engineering Departm.nt Dumlupinar University Kutahya Turkey

To study the effect of the textural properties of rocks on their crushing feature, the distrib.tion of particle size, the texture, grinding and crushing characteristics of the rocks were investigated, and the relations am.ng them.were then analyzed using statistical m.thods. The relations b.tween the textural properties and the physical and m.chanical features of rocks were determ.ned.

关键词： rock textural properties crushing grinding

Com.arative analysis of coal and coal-shale intrinsic factors affecting spontaneous com.0}stion

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International Journal of Coal Science & Technology 2018年第3期5卷 282-294页

作者： m. Onifade b. Genc The School of m.ning Engineering University of the Witwatersrand P.O. WITS Johannesburg 2050 South Africa

Coal and coal-shales tend to undergo spontaneous com.0}stion under favourab.e atm.spheric conditions. Spontaneous com.0}stion liab.lity index and intrinsic properties of coals and coal-shales varies b.tween （ab.ve and b.low） coal seam.. The spontaneous com.0}stion liab.lity index （ob.ained from.the Wits-Ehac Index） and intrinsic properties （ob.ained from.proxim.te, ultim.te, and petrographic analysis） of fourteen sam.les representative of in situ coal （b.tum.nous） and fourteen coal-shales ob.ained in Witb.nk coalfield, South Africa were experim.ntally studied. Com.arative analysis of the relationships b.tween the spontaneous com.0}stion liab.lity index and intrinsic properties of coals and coalshales were estab.ished to evaluate their effects on self-heating potential. The intrinsic properties show linear relationship with spontaneous com.0}stion liab.lity and therefore, identifies the factors affecting spontaneous com.0}stion of these m.terials. The influence of coal-shales intrinsic properties towards spontaneous com.0}stion liab.lity shows higher correlation coefficients than the coals. b.th coals and coal-shales show inertinite m.ceral as m.jor constituents than the vitrinite and liptinite m.cerals, hence the reactivity of inertinite m.cerals m.y show greater influence on spontaneous com.0}stion liab.lity. A definite positive or negative trends exists b.tween the intrinsic properties and spontaneous com.0}stion liab.lity index. This research is part of a larger project which is considering the influence of intrinsic properties of coals and coal-shales on spontaneous com.0}stion liab.lity.

关键词： Coal-shales Spontaneous com.0}stion Liab.lity index Statistical analysis and correlation coefficient