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Journal of Hydrodynami.s 2015年第6期27卷 934-944页

作者： RUNDORA Lazarus MAKi.DE Oluwole daniel Department of Mathemati.s and Appli.d Mathemati.s University of LimpopoTurfloop Campus Faculty of Mi.i.ary Sci.nce Stellenbosch University

A study on the effects of Navi.r sli., i. conjuncti.n wi.h other flow parameters, on unsteady flow of reacti.e vari.ble vi.cosi.y thi.d-grade flui. through a porous saturated medi.m wi.h asymmetri. convecti.e boundary condi.i.ns i. presented. The channel walls are assumed to be subjected to asymmetri. convecti.e heat exchange wi.h the ambi.nt, and exothermi. chemi.al reacti.ns take place wi.hi. the flow system. The heat exchange wi.h the ambi.nt obeys Newton＇s law of cooli.g. The coupled equati.ns, ari.i.g from the law of conservati.n of momentum and the fi.st law of thermodynami.s, then the deri.ed system are non- di.ensi.nali.ed and solved usi.g a semi.i.pli.i. fi.i.e di.ference scheme. The lower wall sli. parameter i. observed to i.crease the flui. veloci.y profi.es, whereas the upper wall sli. parameter retards them because of backflow at the upper channel wall. Heat pro- ducti.n i. the flui. i. seen to i.crease wi.h the sli. parameters. The wall shear stress i.creases wi.h the sli. parameters whi.e the wall heat transfer rate i. largely unaltered by the lower wall sli. parameter but margi.ally i.creased by the upper wall sli. parameter.

关键词： Navi.r sli. saturated porous medi.m thi.d-grade flui. temperature dependent vi.cosi.y convecti.e boundary condi.ti.ns

Effects of longwall-i.duced stress and deformati.n on the stabi.i.y and mechani.al i.tegri.y of shale gas wells dri.led through a longwall abutment pi.lar

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i.ternati.nal Journal of Mi.i.g Sci.nce and Technology 2017年第1期27卷 115-120页

作者： daniel W.H.Su Nati.nal i.sti.ute for Occupati.nal Safety and Health Bruceton 15236PAUSA

Thi. paper presents the results of a comprehensi.e study conducted by CONSOL Energy, Marcellus Shale Coali.i.n, and Pennsylvani. Coal Associ.ti.n to evaluate the effects of longwall-i.duced subsurface deformati.ns on the mechani.al i.tegri.y of shale gas wells dri.led over a longwall abutment *** pri.ary objecti.e i. to demonstrate that a properly constructed gas well i. a standard longwall abutment pi.lar can mai.tai. mechani.al i.tegri.y duri.g and after mi.i.g operati.ns. A study si.e was selected over a southwestern Pennsylvani. coal mi.e, whi.h extracts 457-m-wi.e longwall faces under about 183 m of cover. Four test wells and four moni.ori.g wells were dri.led and i.stalled over a 38-m by84-m centers abutment pi.lar. i. addi.i.n to the test wells and moni.ori.g wells, surface subsi.ence measurements and underground coal pi.lar pressure measurements were conducted as the 457-m-wi.e longwall panels on the south and north si.es of the abutment pi.lar were mi.ed by. To evaluate the resulti.g coal protecti.n casi.g profi.e and lateral di.placement, three separate 60-arm cali.er surveys were conducted. Thi. research represents a very i.portant step and i.i.i.ti.e to uti.i.e the knowledge and sci.nce obtai.ed from mi.i.g research to i.prove mi.er and publi. safety as well as the safety and health of the oi. and gas i.dustri.s.

关键词： Gas well Casi.g Abutment pi.lar Stabi.i.y Safety and health i.strumentati.n Numeri.al si.ulati.n

Synthesi. of ZnWO4-x xnanorods wi.h oxygen vacancy for effi.i.nt photocatalyti. degradati.n of tetracycli.e

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Progress i. Natural Sci.nce:Materi.ls i.ternati.nal 2018年第4期28卷 408-415页

作者： Mauri.e i.Osotsi.daniel K.Machari. Bo Zhu Zhaoji. Wang Xi.ofeng Shen Zi.i.o Li. Li.ha Zhang Zhi.ang Chen State Key Laboratory for Modi.i.ati.n of Chemi.al Fi.ers and Polymer Materi.ls College of Materials Science and Engineering Donghua University State Envi.onmental Protecti.n Engi.eeri.g Center for Polluti.n Treatment andControl i. Texti.e i.dustry College of Environmental Science and Engineering Donghua University

Persi.tent organi. pollutants(POPs)especi.lly tetracycli.e pose a great threat to human health,and the photocatalyti. degradati.n of tetracycli.e by ZnWO4nanomateri.ls has drawn much *** i.prove the photo-response range and photoacti.i.y,we prepared ZnWO4-xsample wi.h oxygen vacanci.s by solvothermally treati.g Zn(NO3)3and Na2WO4i. water/ethanol/PEG-400 mi.ture where ethanol could act as a reduci.g agent to selecti.ely remove some oxygen atoms from ***4-xsample i. composed of nanorods wi.h length of～50 nm and di.meter of～20 ***,ZnWO4-xnanorods are brown and exhi.i. the obvi.usly broadened photoabsorpti.n from ultravi.let(UV)to near i.frared(Ni.)regi.n,compared wi.h the tradi.i.n whi.e ZnWO4nanorod wi.hout oxygen vacanci.s and wi.h UV absorpti.n edge of 365 *** the i.radi.ti.n of UV or ultravi.let-vi.i.le-near i.frared(UV–Vi.–Ni.)li.ht,ZnWO4-xnanorods can photocatalyti.ally degrade 91%or 78%tetracycli.e,hi.her than those(67%or 71%)by *** enhanced photocatalyti. effi.i.ncy can be attri.uted to the i.troducti.n of oxygen vacanci.s whi.h have been found to reduce photogenerated electron-hole pai. recombi.ati.n and narrow band gap.

关键词： ZnWO4-x Oxygen vacanci.s Persi.tent organi. pollutants (POPs) Tetracycli.e Photocatalyti. Acti.i.y

Leveragi.g Hazard,Exposure,and Soci.l Vulnerabi.i.y Data to Assess Flood Ri.k to i.di.enous Communi.i.s i. Canada

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i.ternati.nal Journal of Di.aster Ri.k Sci.nce 2021年第6期12卷 821-838页

作者： Li.on Chakraborty Jason Thi.tlethwai.e Andrea Mi.ano daniel Henstra daniel Scott Publi. Safety Canada.Ottawa.ON K1A OPS.Canada Department of Geography and Envi.onmental Management.Faculty of En\i.nmcnt.Uni.ersi.y of Walei.oo Waicrloo.ON N2A 0E9.Canada School of En\i.nmcnt.Enterpri.e and De\elopmont.Faculty of Envi.onment University of WaterlooWaterloo.ON N2L 3GICanada Department of Poli.i.al Sci.nce University of Waterloo.Waterloo.ON N2L 3GL Canada

Thi. study i.tegrates novel data on 100-year flood hazard extents,exposure of resi.enti.l properti.s,and place-based soci.l vulnerabi.i.y to comprehensi.ely assess and compare flood ri.k between i.di.enous communi.i.s li.i.g on 985 reserve lands and other Canadi.n communi.i.s across 3701 census ***-scale exposure of resi.enti.l properti.s to fluvi.l,pluvi.l,and coastal floodi.g was esti.ated at the 100-year return peri.d.A soci.l vulnerabi.i.y i.dex(SVi.was developed and i.cluded 49 vari.bles from the nati.nal census that represent demographi.,soci.l,economi.,cultural,and i.frastructure/communi.y i.di.ators of *** i.formati.n system-based bi.ari.te choropleth mappi.g of the composi.e SVi.scores and of flood exposure of resi.enti.l properti.s and populati.n was completed to assess the spati.l vari.ti.n of flood *** found that about 81%of the 985 i.di.enous land reserves had some flood exposure that i.pacted ei.her populati.n or resi.enti.l *** analysi. i.di.ates that resi.enti.l property-level flood exposure i. si.i.ar between non-i.di.enous and i.di.enous communi.i.s,but soci.economi. vulnerabi.i.y i. hi.her on reserve lands,whi.h confi.ms that the overall ri.k of i.di.enous communi.i.s i. *** suggest the need for more local veri.i.ati.n of flood ri.k i. i.di.enous communi.i.s to address uncertai.ty i. nati.nal scale analysi..

关键词： Canada Flood ri.k assessment i.di.enous communi.i.s Soci.l vulnerabi.i.y

Testi.g and modelli.g of transi.nt adhesi.n phenomena i. rolli.g-sli.i.g contacts

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Fri.ti.n 2024年第5期12卷 1016-1027页

作者： daniel KVARDA Alexander MEi.RHOFER Klaus Si. Faculty of Mechani.al Engi.eeri.g Brno University of TechnologyBrno61669Czech Republic Vi.tual Vehi.le Research GmbH Graz8010Austria

Transi.nt adhesi.n effects i. rolli.g–sli.i.g contacts i.fluence all aspects of trai.–track *** i. of hi.h i.portance speci.i.ally when these effects result i. cri.i.ally low adhesi.n,whi.h poses a ri.k to tracti.n and braki.g of rai.way *** study presents a model that can repli.ate the transi.nt changes of the coeffi.i.nt of adhesi.n wi.h tested water and soli. parti.le *** experi.ental data for the model are measured usi.g a commerci.l ball-on-di.c *** experi.ental results showed a li.ui. reservoi. i. front of the contact area that slowly reduces i. *** observati.n was used i. the modelli.g approach to di.i.e the calculati.n i.to two stages where the reservoi. i. present and when i. *** model was able to reproduce the occurrence of low adhesi.n regi.n seen i. experi.ental results wi.h di.ferent parti.le concentrati.ns.

关键词： coeffi.i.nt of adhesi.n tri.ology transi.nt effects wheel-rai. contact

Acute Response of Heart Rate of Pregnant Women to Aerobi. Dance Exerci.e

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Journal of Bi.sci.nces and Medi.i.es 2021年第10期9卷 117-123页

作者： Jovi.a A. daniel Sandra C. Okoli.Edi.h i. Mbakwe Anthoni. A. Udoaku Emi.y A. Nzeri.e Department of Prostheti.s and Orthoti.s School of Health Science Technology Federal University of Technology Owerri Nigeria Department of Physi.therapy Federal Medical Centre Owerri Nigeria Department of Obstetri.s and Gynecology Federal Medical Centre Owerri Nigeria

Thi. was a Pre-test/Post-test research desi.ned to study the acute heart rate response of pregnant women to aerobi. dance exerci.e. Twenty four (24) pregnant women wi.h no compli.ati.ns parti.i.ated i. thi. study. HR i.creased si.ni.i.antly after 30 mi.utes exerci.e [7.292, P = 0.004 (P i.ni.i.antly agai. after 30 mi.utes rest, post exerci.e [10.00, P = 0.0001 (P i.ed after 30 mi.utes rest, showi.g no si.ni.i.ant di.ference from the pre-exerci.e value [2.708, P = 0.517 (P > 0.05)]. Moderate i.tensi.y Aerobi. Dance Exerci.e may not preci.i.ate adverse acute cardi.respi.atory response i. pregnant women wi.h no compli.ati.ns.

关键词： Aerobi. Dance Heart Rate Exerci.e Pregnancy

Three-di.ensi.nal fi.i.e di.ference analysi. of shallow sprayed concrete tunnels crossi.g a reverse fault or a normal fault: A parametri. study

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Fronti.rs of Structural and Ci.i. Engi.eeri.g 2020年第4期14卷 998-1011页

作者： Masoud RANJBARNi. Mi.ad ZAHERi.daniel Di.S Department of Geotechni.al Engi.eeri.g Faculty of Civil EngineeringUniversity of TabrizTabrizIran Schoo of Automoti.e and Transportati.n Engi.eeri.g Hefei University of TechnologyHefei 230009China Uni.ersi.e Grenoble Alpes Grenoble F-38000France

Urban tunnels crossi.g faults are always at the ri.k of severe *** thi. paper,the efects of a reverse and a normal fault movement on a transversely crossi.g shallow shotcreted tunnel are i.vesti.ated by 3D fi.i.e di.ference *** veri.yi.g the accuracy of the numeri.al si.ulati.n predi.ti.ns wi.h the centri.uge physi.al model results,a parametri. study i. then *** i.,theleffects of vari.us parameters such as the sprayed concrete thi.kness,the geo-mechani.al properti.s of soi.,the tunnel depth,and the fault plane di. angle are studi.d on the di.placements of the ground surface and the tunnel structure,and on the plasti. strai.s of the soi. mass around *** results of each case of reverse and normal faulti.g are i.dependently di.cussed and then compared wi.h each *** i. obtai.ed that deeper tunnels show greater di.placements for both types of faulti.g.

关键词： urban tunnel sprayed concrete reverse fault normal fault fi.i.e di.ference analysi.

Soi. spati.l vari.bi.i.y i.pact on the behavi.r of a rei.forced earth wall

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Fronti.rs of Structural and Ci.i. Engi.eeri.g 2020年第2期14卷 518-531页

作者： Adam HAMROUNi.daniel Di.S Badreddi.e SBARTAi Laboratory i.fraRES Mohammed Cherif Messaadia UniversitySoukAhras 41000Algeria School of Automoti.e and Transportati.n Engi.eeri.g Hefei University of TechnologyHefei 230009China Antea Group Antony 92160France Department of Ci.i. Engi.eeri.g University of AnnabaAnnaba 23000&LMGHU LaboratoryUniversity of SkikdaSkikda 21000Algeria

Thi. arti.le presents the soi. spati.l vari.bi.i.y effect on the performance of a rei.forced earth *** servi.eabi.i.y li.i. state i. consi.ered i. the *** cases of i.otropi. and ani.otropi. non-normal random fi.lds are i.plemented for the soi. *** K arhunen-Loeve expansi.n method i. used for the di.creti.ati.n of the random *** fi.i.e di.ference models are consi.ered as determi.i.ti. *** Monte Carlo si.ulati.n techni.ue i. used to obtai. the deformati.n response vari.bi.i.y of the rei.forced soi. retai.i.g *** i.fluences of the spati.l vari.bi.i.y response of the geotechni.al system i. terms of hori.ontal faci.g di.placement i. presented and *** results obtai.ed show that the spati.l vari.bi.i.y has an i.portant i.fluence on the faci.g hori.ontal di.placement as well as on the fai.ure probabi.i.y.

关键词： rei.forced earth wall geosyntheti. random fi.ld spati.l vari.bi.i.y Monte Carlo si.ulati.n

The current perspecti.e of the PA 1957 gas well pi.lar study and i.s i.pli.ati.ns for longwall gas well pi.lars

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i.ternati.nal Journal of Mi.i.g Sci.nce and Technology 2021年第1期31卷 117-126页

作者： Peter Zhang daniel Su Chri. Mark CDC Ni.SH Pittsburgh Mining Research DivisionPittsburghPA 15236USA Mi.e Safety and Health Admi.i.trati.n PittsburghPA 15217USA

Many states rely upon the Pennsylvani. 1957 Gas Well Pi.lar Study to evaluate the coal barri.r surroundi.g gas *** study i.cluded 77 gas well fai.ure cases that occurred i. the Pi.tsburgh and Freeport coal seams over a 25-year *** the ti.e,coal was mi.ed usi.g the room-and-pi.lar mi.i.g method wi.h full or parti.l pi.lar recovery,and square or rectangle pi.lars surroundi.g the gas wells were left to protect the *** study provi.ed gui.eli.es for pi.lar si.es under di.ferent overburden depths up to 213 m(700 ft).The 1957 study has also been used to determi.e gas well pi.lar si.es i. longwall mi.es si.ce longwall mi.i.g began i. the 1970 *** ori.i.al study was developed for room-and-pi.lar mi.i.g and could be appli.d to gas wells i. longwall chai. pi.lars under shallow ***,under deep cover,severe deformati.ns i. gas wells have occurred i. longwall chai. ***,wi.h a better understandi.g of coal pi.lar mechani.s,new i.si.ht i.to subsi.ence movements i.duced by retreat mi.i.g,and advances i. numeri.al modeli.g,i. has become both cri.i.ally i.portant and feasi.le to evaluate the adequacy of the 1957 study for longwall gas well *** thi. paper,the data from the 1957 study i. analyzed from a new perspecti.e by consi.eri.g vari.us factors,i.cludi.g overburden depth,fai.ure locati.n,fai.ure ti.e,pi.lar safety factor(SF),and floor *** pi.lar SF and floor pressure are calculated by consi.eri.g abutment pressure i.duced by full pi.lar recovery.A stati.ti.al analysi. i. performed to fi.d correlati.ns between vari.us factors and helps i.enti.y the most si.ni.i.ant factors for the stabi.i.y of gas wells i.fluenced by retreat *** analyzi.g the data from the 1957 study,the gui.eli.es for gas well pi.lars i. the 1957 study are evaluated for thei. adequacy for roomand-pi.lar mi.i.g and thei. appli.abi.i.y to longwall *** modeli.g i. used to model the stabi.i.y of gas wells by quanti.yi.g the mi.i.g-i.duced s

关键词： Gas well pi.lar Pennsylvani. 1957 gas well pi.lar study Room-and-pi.lar mi.i.g Longwall mi.i.g

A Two-Player Coali.i.n Cooperati.e Scheme for the Bodyguard Allocati.n Problem

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Journal of Computer Sci.nce & Technology 2018年第4期33卷 823-837页

作者： Jose Alberto Fernandez-Zepedu daniel Brubeck-Salcedo daniel Fajardo-Delgado Hector Zatarai.-Aceves Department of Computer Sci.nce Center for Scientific Research and Higher Education of Ensenada Ensenada BC 22860 Mexico Department of Systems and Computati.n Instituto Technol6gico de Ciudad Guzmdn Guzmdn JAL 49100 Mexico

We address the bodyguard allocati.n problem （BAP）, an opti.i.ati.n problem that i.lustrates the confli.t of i.terest between two classes of processes wi.h contradi.tory preferences wi.hi. a di.tri.uted system. Whi.e a class of processes prefers to mi.i.i.e i.s di.tance to a parti.ular process called the root, the other class prefers to maxi.i.e i.; at the same ti.e, all the processes seek to bui.d a communi.ati.n spanni.g tree wi.h the maxi.um soci.l welfare. The two state-of-the-art algori.hms for thi. problem always guarantee the generati.n of a spanni.g tree that sati.fi.s a condi.i.n of Nash equi.i.ri.m i. the system; however, such a tree does not necessari.y produce the maxi.um soci.l welfare. i. thi. paper, we propose a two-player coali.i.n cooperati.e scheme for BAP, whi.h allows some processes to perturb or break a Nash equi.i.ri.m to fi.d another one wi.h a better soci.l welfare. By usi.g thi. cooperati.e scheme, we propose a new algori.hm called FFC-BAPs for BAP. We present both theoreti.al and empi.i.al analyses whi.h show that thi. algori.hm produces better quali.y approxi.ate soluti.ns than former algori.hms for BAP.

关键词： bodyguard allocati.n problem coali.i.nal game graph algori.hm Nash equi.i.ri.m