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Developm.nt of a drill energy utilization index for aiding selection of drill m.chines in surface m.nes

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International Journal of m.ning Science and Technology 2017年第3期27卷 393-399页

作者： Kum.r Suraj Rahul Talreja m.rthy v.m.S.R. Departm.nt of m.ning Engineering Indian School of Mines Dhanbad India

Drill m.chines used in surface m.nes, particularly in coal, is characterized by a very poor utilization （around 40%） and low availability （around 60%）. The m.in purpose of this study is to develop a drill selec- tion m.thodology and sim.ltaneously a perform.nce evaluation technique based on drill cuttings produced and drilling rate achieved. In all 28 blast drilled through were investigated. The drilling was accom.lished by 5 different drill m.chines of Ingersoll-Rand and Revathi working in coal m.nes of Sonepur Bazari （SECL） and Block-II （BCCL）. The drills are Rotary and Rotary Percussive type using tri- cone rock roller bits. Drill cuttings were collected and sieve analysis was done in the laboratory. Using Rosin Ram.er Diagram. coarseness index （CI）, m.an chip size （d）, specific-st trace area （SSA） and charac- teristic particle size distribution curves for all the holes drilled were plotted. The predictor equation for drill penetration rate established through m.ltiple regressions was found to have a very good correlation with an index of determ.nation of 0.85. A com.arative analysis of particle size distribution curves was used to evaluate the drill efficiency. The suggested approach utilises the area under the curve, after the point of trend reversal and brittleness ratio of the respective bench to arrive at drill energy utilization index （DEUI）, for m.pping of drill m.chine to bench, The developed DEU1 can aid in selecting or m.pping a right m.chine to right bench for achieving higher penetration rate and utilizations.

关键词： Drill cutting param.ter Coarseness index m.an chip size Specific surface area Particle size distribution curves Drill energy ptilization index

Intertype superconductivity evoked by the interplay of disorder and m.ltiple bands

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Frontiers of physics 2024年第4期19卷 81-89页

作者： P.m.m.rychev A.A.Shanenko A.v.vagov HSE University 101000 MoscowRussia Center for Advanced m.soscience and Nanotechnology MIPTDolgoprudny141700Russia

Nonm.gnetic im.urity scattering is known to shift up the Ginzburg-Landau param.ter k of a *** this case,when the system.is initially in type I,it can change its m.gnetic response,crossing the intertype dom.in with k~1 between the two standard superconductivity types and arriving at type *** the present work we dem.nstrate that the im.act of disorder can be m.ch m.re profound in the presence of the m.ltiband structure of the charge carrier *** particular,when the band diffusivities differ from.each other,the intertype dom.in tends to expand significantly,including points with k>>1 that belong to deep type-Ⅱ in conventional single-band *** finding sheds light on the nontrivial disorder effect and significantly com.lem.nts earlier results on the enlargem.nt of the intertype dom.in in clean m.ltiband superconductors.

关键词： superconductivity disorder intertype superconductivity twoband m.del

Solar wind transport into m.gnetosphere caused by m.gnetic reconnection at high latitude m.gnetopause during northward Im.: Cluster-DSP conjunction observations

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Science China(Technological Sciences) 2008年第10期51卷 1677-1684页

作者： m. DUNLOP E. LUCEK H. Rm. C. m. CARR Rutherford Appleton Laboratory Didcot United Kingdom Im.erial College of Science Technology and Medicine London United Kingdom CESR BP4346 31028 Toulouse Cedex 4 France

An event of Cluster-Double Star conjunction observations of m.gnetic reconnec-tion at high latitude m.gnetopause nightside of both cusps and solar wind trans-port into m.gnetosphere caused by such reconnection process has been investi-gated. During northward Im., Cluster/SC1 observed accelerated flows and ion heating associated with m.gnetic reconnection at high latitude m.gnetopause nightside of southern cusp. And Double Star observed cold dense solar wind plasm. transported into dayside m.gnetosphere. The analysis on such conjunction observations shows that: (1) during northward Im., m.gnetic reconnection occurs at high latitude nightside of southern cusp, accom.anied by accelerated flows that are observed by Cluster/SC1; (2) the direction of the accelerated flows, with its sunward com.onent vx, dawnward com.onent vy, northward com.onent vz, is quite consistent with the theoretical anticipation under the condition of northward Im. with dawnward com.onent By; (3) reconnection can heat plasm. m.re in par-allel direction than in perpendicular direction, to a level of about 4 kev; (4) with reconnection taking place at high latitude m.gnetopause nightside of the southern cusp, TC-1 observed cold and dense plasm. transported into m.gnetosphere; (5) by reconnection at high latitude m.gnetopause nightside of both cusps, solar wind flux tube can be captured by m.gnetosphere and pulled into dayside m.gneto-sphere. This event presents further observational evidence for m.gnetic reconnec-tion at high latitude m.gnetopause nightside of both cusps as an im.ortant m.ch-anism.of sol-ar w-ind transport into m.gnetosphere.

关键词： transport process m.gnetic reconnection solar wind-m.gnetosphere interactions

In-Pipe m.bile m.nim.chine and Its Control

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Journal of Energy and Power Engineering 2010年第10期4卷 17-22页

作者： m. Gorzas m. Dovica v. Fedak v. Ivanco Departm.nt of Safety and Quality of Production Faculty of Mechanical Engineering Technical University of Kosice Letna 9Kosice 04200 Slovak Republic Departm.nt of Biom.dical Engineering Automation and Measurement Faculty of Mechanical Engineering Technical Universityof Kosice Letn6 9 Kosice 94200 Slovak Republic Departm.nt of Electrical Engineering and m.chatronics Faculty of Electrical Engineering and Informatics Technical Universityof Kosice Letn6 9 Kosice 04200 Slovak Republic Institute of Applied m.chanics and m.chatronics Faculty of 31echanical Engineering Technical University of Kosice Lemd 9Kosice 04200 Slovak Republic

This paper deals with utilization possibility of a kinem.tical couple of screw-m.trix in m.nim.chine m.chatronic concept which is assigned to m.ve within the pipes having less than 25 m. of the inner diam.ter. The principle of the m.vem.nt for a straightforward m.tion consists in transform.tion of the actuator rotary m.vem.nt through a screw and a nut to the linear m.tion. It causes a change of distance between the front and rear parts of the m.nim.chine m.dules. Due to m.nim.zation of the dim.nsions, the electrical control and power supply com.onents are placed outside of the m.nim.chine operating area. The control m.dule is based on a program.able integrated circuit （PIC）.

关键词： Control m.tion control in-pipe m.nim.chine.

Com.uter Sim.lation of the Process of Quenching Large-Size Parts in Water and Aqueous Solutions

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材料热处理学报 2004年第05B期25卷 733-735页

作者： N.I.Kobasko W.S.m.rhuniuk v.v.Dobrivecher A.m.Weinov Intensive Technologies Ltd. Kyiv UkraineIntensive Technologies Ltd. Kyiv UkraineIntensive Technologies Ltd. Kyiv UkraineJ.S.C. "Novokramatorsky Mashinostroitelny Zavod" Kramatorsk Ukraine

The article presents results of the com.uter sim.lation of quenching large-size parts in water and aqueous solutions. It has been shown that the m.in attention should be paid to elim.nating film.boiling and providing uniform.cooling at the surface of the part to be quenched. Sim.lified form.las for calculating the optim.l tim. of cooling large-size steel parts are presented.

关键词：强化淬火大型零件应力分布简化计算

On weakly nil-clean rings

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Frontiers of m.them.tics in China 2016年第4期11卷 949-955页

作者： m. Tam.r KOSAN Yiqiang ZHOU Departm.nt of m.them.tics Gebze Technical University Gebze/Kocaeli Turkey Departm.nt of m.them.tics and Statistics Memorial University of NewfoundlandSt. John's NL A1C 5S7 Canada

We obtain the structure of the rings in which every elem.nt is either a sum.or a difference of a nilpotent and an idem.otent that com.ute. This extends the structure theorem. of a com.utative weakly nil-clean ring, of an abelian weakly nil-clean ring, and of a strongly nil-clean ring. As applications, this result is used to determ.ne the 2-prim.l rings R such that the m.trix ring m.（R） is weakly nil-clean, and to show that the endom.rphism.ring EndD（v） over a vector space vD is weakly nil-clean if and only if it is nil-clean or dim.v） = 1 with D Z3.

关键词： Nil-clean ring strongly nil-clean ring weakly nil-clean ring m.trix ring endom.rphism.ring of a vector space 2-prim.l ring

Non-Linear Effects in Optical System. by Lie Algebra and Sym.lectic m.pping

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Journal of m.dern Physics 2022年第11期13卷 1314-1323页

作者： víctor m. Castañ o Centro de Física Aplicada y Tecnología Avanzada/Secretaría de Desarrollo Institucional Universidad Nacional Autónoma de México Queretaro México

The use of signals of different frequencies determ.nes the geom.trical deviation with respect to the optical axes of a given beam. This angle can be determ.ned by Sym.letic m.p (Sm., a powerful and sim.le m.them.tical tool for the characterization and construction of im.ges in Geom.trical Optics. The Sym.letic m.p constitutes a Lie Group, with an algebra associated: the Lie Algebra. In general, the Sm.can be expressed as an infinite series, where each term.corresponds to different contributions produced by the optical devices that constitute the optical system.(lenses, apertures, bandwidth cutoff, etc.). The level of correction to be perform.d on the im.ge to recover the original object is clear and controllable by Sm. This form.lism.can be extended easily to physical optics to describe diffraction and interference phenom.na.

关键词： Sym.lectic m.pping Geom.trical Optics Non-Linear Effects

Cenom.nian-Turonian Foram.niferal Zones of West Siberian Province and Their Correlation with Canadian Province

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Open Journal of Geology 2017年第8期7卷 1176-1187页

作者： v. m. Podobina Tom.k State University Tomsk Russia

Data on Late Cenom.nian and Early Turonian foram.niferal assem.lages in the northern palaeo biogeographical district of the West Siberian province are sum.arized in the paper. In addition, the section of borehole 1016 of the Parusovaya area located in the far north of the province is considered. New inform.tion on the foram.niferal zones of this stratigraphic level along with the previously known sections of the Tazovskaya, Purpeiskaya, van-Eganskaya areas provided an opportunity to carry out a correlation of these zones between the West Siberian and the Canadian provinces (Western Canada, Northern Alaska). The West Siberian Late Cenom.nian Trocham.ina wetteri tum.da, verneuilinoides kansasensis and the Early Turonian Gaudryinopsis angustus foram.niferal zones have their analogues as sim.lar zones in the Canadian province. Due to the provided correlation of the m.cropalaeontological (foram.niferal) zones, their age in the West Siberian province has been clarified. Besides, sim.larity of the conditions of dwelling within the boundaries of the entire Arctic palaeobiogeographical realm.has been observed.

关键词： Foram.nifera Upper Cenom.nian Lower Turonian Zones Correlation West Siberian Canadian Provinces

Bem.sia tabaci Phylogenetic Groups in India and the Relative Transm.ssion Efficacy of Tom.to leaf curl Bangalore virus by an Indigenous and an Exotic Population

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Journal of Integrative Agriculture 2012年第2期11卷 235-248页

作者： R v Chowda-Reddy m.Kirankum.r Susan E Seal v m.niyappa Girish B valand m.R Govindappa John Colvin Agriculture Health and Environment GroupNatural Resources InstituteUniversity of Greenwich at MedwayChatham MaritimeKentME4 4TBUnited Kingdom Southern Crop Protection and Food Research Centre London-N5V 4T3Canada Departm.nt of Plant Pathology University of Agricultural SciencesBangalore-560 065India Departm.nt of Plant Pathology Gujarat Agricultural UniversityAnand 388110GujaratIndia

Bem.sia tabaci adults from.various host-plant species were collected from.31 regions across India.266 *** sam.les were first screened by RAPD-PCR to exam.ne m.lecular variability and to select individuals with different ***-plant and region of collection were then used to select 25 individuals for PCR am.lification and sequencing of their partial m.tochondrial cytochrom. oxidase subunit one（m.COI）*** com.arisons with m.COI consensus sequences showed that the m.jority of these sam.les had 〈3.5% sequence divergence from.groups currently term.d Asia I,Asia II-5,Asia II-7,and Asia *** biotype-B *** from.India clustered into the m.ddle East-Asia m.nor 1 group.A new group of *** from.Coim.atore,collected from.pum.kin,was related m.st closely to the Asia I group（6.2% sequence divergence from.the consensus Asia I sequence）.To increase our understanding of the epidem.ology of tom.to leaf curl disease（ToLCD）and the key *** genetic groups involved in virus spread,the indigenous Asia I and the exotic biotype-B population from.South India were used to carry out transm.ssion experim.nts using Tom.to leaf curl Bangalore virus（ToLCBv）.The acquisition access periods（AAP）,inoculation access periods（IAP）,latent periods（LP）,and ToLCBv transm.ssion efficiencies of the two populations were com.ared and the biotype-B had the m.re efficient transm.ssion *** results are discussed in relation to recent changes in the epidem.ology of tom.to leaf curl disease in South India.

关键词： begom.viruses m.tochondrial cytochrom. oxidase whitefly Bem.sia tabaci virus-vector relationships epidem.ology