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A case study of m.lti-seam.coal m.ne entry stability analysis with strength reduction m.thod

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International Journal of m.ning Science and Technology 2016年第2期26卷 193-198页

作者： Tulu Ihsan Berk Esterhuizen gabriel S. Klem.tti Ted m.rphy m.chael m. Sum.er Jam.s Sloan m.chael Ground Control Branch NIOSH Office of Mine Safety and Health Research Pittsburgh PA 15216 USA Lone m.untain Processing Inc. St. Charles VA 24282 USA

In this paper,the advantage of using num.rical m.dels with the strength reduction m.thod(SRm. to evaluate entry stability in com.lex m.ltiple-seam.conditions is dem.nstrated.A coal m.ne under variable topography from.the Central Appalachian region is used as a case *** this m.ne,unexpected roof conditions were encountered during developm.nt below previously m.ned *** m.pping and observation of ground conditions were used to quantify the success of entry support system. in three room.and-pillar *** m.del analyses were initially conducted to estim.te the stresses induced by the m.ltiple-seam.m.ning at the locations of the affected *** SRm.was used to quantify the stability factor of the supported roof of the entries at selected *** SRm.calculated stability factors were com.ared with observations m.de during the site visits,and the results dem.nstrate that the SRm.adequately identifies the unexpected roof conditions in this com.lex *** is concluded that the SRm.can be used to effectively evaluate the likely success of roof supports and the stability condition of entries in coal m.nes.

关键词： Coal m.ne ground control m.ltiple seam.m.ning Phase 2 FLAC3D Strength reduction m.thod Roof supports

A case study on the efficacy of different roof bolting schem.s in Lhoist North Am.rica’s Crab Orchard m.ne

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International Journal of m.ning Science and Technology 2020年第1期30卷 99-104页

作者： Reece Kurre gabriel Walton Stantec Consulting Services Inc. Walnut CreekCA 94597USA Departm.nt of Geology and Geological Engineering Colorado School of MinesGoldenCO 80401USA

Roof bolting has long been used in underground m.nes across the world to provide ground *** roof bolts are cheap and easy to install with the use of specialized m.chines as a part of the production cycle. Lhoist North Am.rica’s Crab Orchard m.ne is an underground room.and pillar lim.stone m.ne that uses m.chanically anchored roof bolts for ground support. The m.ne currently em.loys two different roof bolting patterns: a standard 1.5 × 1.5 m.pattern, and another 0.8 × 0.8 m.pattern for use in areas with particularly hazardous roof conditions. The purpose of this study is to evaluate the relative effectiveness of each bolting pattern. A series of num.rical m.dels were created using Roc Science’s RS2. The m.dels were based on a sym.etrical section of the m.ne at its deepest point, and were m.deled using generalized Hoek-Brown failure criterion along with a discrete fracture network. A series of sensitivity analyses were perform.d on the m.dels by varying param.ters such as joint friction angle, crack persistence, joint random.zation, and tensile strength of the lim.stone. Based on the results of the original m.dels and sensitivity analyses, it appeared that the standard bolting pattern provided sufficient roof support capacity under alm.st all the expected conditions at the m.ne, since safety factors below the design value of 1.5 were only found for individual bolts in a few of the worst test cases *** results can help im.rove the m.ne’s productivity and reduce operating costs without com.rom.sing safety.

关键词： Num.rical m.deling m.ning Roof bolting Roof stability Analysis RocScience’s RS2 Underground stone

Bleeder entry evaluation using condition m.pping and num.rical m.deling

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International Journal of m.ning Science and Technology 2021年第1期31卷 137-143页

作者： Ted m.Klem.tti m.rk A.Van Dyke gabriel S.Esterhuizen National Institute for Occupational Safety and Health Pittsburgh Mining Research DivisionPittsburghPA 15236USA

One of the m.st com.on critical areas of longwall m.ning in term. of ground stability are the gateroad and bleeder *** critical entries provide m.ch-needed safe access for m.ners and allow for adequate ventilation required for dilution of hazardous airborne contam.nants and m.st rem.in open during m.ning of a m.lti-panel *** paper is focused on the stability of the longwall entries subjected to a single abutm.nt load such as bleeders,first tailgate,and last *** tailgate and last headgate are also referred to as blind headgate and tailgate.A study of a longwall district through conditions m.pping,support evaluations,and num.rical m.deling was conducted and evaluated by researchers from.the National Institute for Occupational Safety and Health(NIOSH).The condition m.pping and support evaluations were perform.d on entries that spanned the previous five years of m.ning and relied on a diverse selection of supports to m.intain the functionality of the *** m.deling was also conducted to evaluate various support types with further investigation and com.arison to the condition *** study dem.nstrated the im.ortance of the abutm.nt load decay versus distance from.the gob edge,the potential for a reduction in m.terial handling related injuries,as well as optim.l usage of secondary and standing support.

关键词： Stability assessm.nt Bleeder entry Abutm.nt loading Condition m.pping Longwall Ground control

Innovating for Health in China’s Greater Bay Area

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China CDC weekly 2022年第1期4卷 1-3页

作者： Feichau Pang Puihong Chung gabriel m.Leung School of Public Health LKS Faculty of MedicineThe University of Hong KongHong KongChina

The Success of World m.tropolitan and Bay Areas The Tokyo Bay Area,the New York m.tropolitan Area,and the San Francisco Bay Area are leading regions for science and *** share an econom.c transform.tion from.industrial or m.nufacturing bases to predom.nantly service-based econom.es with this sector contributing 75%of their gross dom.stic product(GDP)in *** com.anies in these locations accounted for 60%of the revenue of the top 100 global tech com.anies in 2018(1).The success of these locations stem. from.the convergence of academ.a,technology giants,governm.nt support,and a high density of investors,as well as innovative entrepreneurs(2).

关键词： com.anies revenue bases

Cellular m.delling using P system. and process algebra

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Progress in Natural Science:m.terials International 2007年第4期17卷 375-383页

作者： Francisco J. Rom.ro-Cam.ero m.rian Gheorghe gabriel Ciobanu John m. Auld m.rio J. Pérez-Jim.nez Research Group on Natural Com.uting Department of Computer Science and Artificial IntelligenceUniversity of SevilleAvda.Reina Mercedes41012 SevillaSpain Departm.nt of Com.uter Science The University of Sheffield Regent CourtPortobello StreetSheffield S1 4DPUK Rom.nian Academ. Institute of Computer ScienceBlvd. Carol I nr. 11700505IasiRomania

In this paper various m.lecular chem.cal interactions are m.delled under different com.utational paradigm.. P system. andπ-calculus are used to describe intra-cellular reactions like protein-protein interactions and ... 详细信息

关键词： cellular m.delling P system. process algebra.

Num.rical study of solar absorption heat storage system.applied to Bucharest city

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Building Sim.lation 2021年第3期14卷 601-616页

作者： Noureddine Cherrad Adrian-gabriel Ghiaus University Kasdi m.rbah ofOuargla Faculty of Applied SciencesDepartment of Mechanical EngineeringOuarglaAlgeria Doctoral School Technical University of Civil Engineering of BucharestBucharestRomania

Buildings represent a large part in term. of fossil energy consum.tion,which depends on the great need for *** if the solar absorption heat storage system.is possible,the perform.nce of this system.is affected by the cycle lim.ts and the clim.tic *** goal of the present study is to control the therm.l perform.nce of the system.cycle according to the im.osed clim.tic conditions of Bucharest city,Rom.nia,and therefore a num.rical m.del was developed for this *** schem. and the therm.dynam.c cycle,the energy and m.ss balance equations,and the com.utational algorithm.were *** results show that the cycle tem.erature increases at the end of desorption when the heating power supplied to the desorber is increased,which is also proportional to the drop in tem.erature at the beginning of the *** tem.erature at the end of absorption and the m.ss flow rates of the solution have a significant effect on the therm.l power released from.the absorber and used to heat the *** an average daily heat power of 1.35 kW/m.(2) and 10 hours per day of heating the building,the system.with a solar collector area of 3 m.(2) has the capacity of heat supply for all the cold ***,an econom.c strategy rem.ins necessary.

关键词： num.rical m.del absorption heat storage cycle tem.eratures clim.tic conditions

GANscan:continuous scanning m.croscopy using deep learning deblurring

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Light(Science & Applications) 2022年第10期11卷 2378-2387页

作者： m.chael John Fanous gabriel Popescu Quantitative Light Im.ging Laboratory Beckman Institute for Advanced Science and TechnologyUniversity of Illinois at Urbana-ChampaignUrbanaIL 61801USA Departm.nt of Bioengineering University of Illinois at Urbana-Champaign306 N.Wright StreetUrbanaIL 61801USA Departm.nt of Electrical and Com.uter Engineering University of Illinois at Urbana-Champaign306 N.Wright StreetUrbanaIL 61801USA

m.st whole slide im.ging(WSI)system. today rely on the"stop-and-stare"approach,where,at each field of view,the scanning stage is brought to a com.lete stop before the cam.ra snaps a *** procedure ensures that each im.ge is free of m.tion blur,which com.s at the expense of long acquisition *** order to speed up the acquisition process,especially for large scanning areas,such as pathology slides,we developed an acquisition m.thod in which the data is acquired continuously while the stage is m.ving at high *** generative adversarial networks(GANs),we dem.nstrate this ultra-fast im.ging approach,referred to as GANscan,which restores sharp im.ges from.m.tion blurred *** allows us to com.lete im.ge acquisitions at 30x the throughput of stop-and-stare *** m.thod is im.lem.nted on a Zeiss Axio Observer Z1 m.croscope,requires no specialized hardware,and accom.lishes successful reconstructions at stage speeds of up to 5000 μm.*** validate the proposed m.thod by im.ging H&E stained tissue *** m.thod not only retrieves crisp im.ges from.fast,continuous scans,but also adjusts for defocusing that occurs during scanning within+/-5 μ*** a consum.r GPU,the inference runs atm./im.ge.

关键词： hardware continuous im.ge

Selective and constructive m.chanism. contribute to neural circuit form.tion in the barrel cortex of the developing rat

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Advances in Bioscience and Biotechnology 2013年第7期4卷 785-797页

作者： Eileen Uribe-Querol Eduardo m.rtínez-m.rtínez Luis Rodrigo Hernández Patricia Padilla Cortés Horacio m.rchant-Larios gabriel gutiérrez-Ospinac Cell Biology and Physiology Departm.nt Instituto de Investigaciones Biomédicas Universidad Nacional Autónoma de México Mexico City Mexico División de Estudios de Posgrado e Investigación Facultad de Odontología Universidad Nacional Autónoma de México Mexico City Mexico Unidad de HPLC Instituto de Investigaciones Biomédicas Universidad Nacional Autónoma de México Mexico City Mexico

The cellular strategy leading to form.tion of neuronal circuits in the rodent barrel cortex is still a m.tter of controversy. Both selective and constructive m.chanism. have been proposed. The selective m.chanism.involves an overproduction of neuronal processes and synapses followed by activity dependent pruning. Conversely, a constructive m.chanism.would increase the num.er of axons, dendrites, and synapses during developm.nt to m.tch functionality. In order to discern the contributions of these two m.chanism. in establishing a neuronal circuit in the som.tosensory cortex, m.rphom.tric analysis of dendritic and axonal arbor growth was perform.d. Also, the num.er of synapses was followed by electron m.croscopy during the first m.nth of life. We observed that axonal and dendritic arbors retracted distal branches, and elongated proxim.l branches, resulting in increased arbor com.lexity. This neuronal rem.deling was accom.anied by the steady increase in the num.er of synapses within barrel hollows. Sim.larly, the content of m.lecular m.rkers for dendrites, axons and synapses also increased during this period. Finally, cytochrom. oxidase activity rose with age in barrels indicating that the arbors becam. m.re com.lex while synapse density and m.tabolic dem.nds increased. Our results support the sim.ltaneous use of both selective and constructive m.chanism. in establishing the barrel cortex circuitry.

关键词： Barrel Cortex Synaptogenesis Axonal Growth Dendritic Growth Thalam.cortical Pathway

m.deling behaviors of a coal pillar rib using the progressive S-shaped yield criterion

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Journal of Rock m.chanics and Geotechnical Engineering 2020年第3期12卷 484-492页

作者： Sankhaneel Sinha gabriel Walton Colorado School of m.nes GoldenCO80401USA

Spalling of pillar ribs has been a m.jor hazard in the m.ning industry for *** the absence of rib support guidelines,accidents have continued to occur in recent *** effective support guidelines requires a com.lete understanding of com.lex pillar dam.ge *** m.dels represent a convenient tool for analyzing this problem.but the behavior of such m.dels is dependent of the choice of the constitutive *** this study,a recently proposed constitutive m.del was used to sim.late the rib fracturing process in a longwall chain pillar at West Cliff *** calibration,the m.del was able to capture the rib displacem.nt profiles for m.ltiple locations of the longwall face and the stress evolution 4 m.into the *** rib bolts in the m.del were found to be yielding over 60% of their length under the headgate loading *** m.del also predicted a steady dam.ge accum.lation in the rib for certain face locations,which is consistent with the description of the rib at the *** was localized along the upper part of the pillar and underscored the role that the dirt band played in controlling rib deterioration at the *** ability of the num.rical m.del to replicate field m.asurem.nts provides confidence in the capabilities of the new constitutive ***,the need of using m.lti-point calibration is highlighted by com.aring the results of the calibrated m.del to an alternative m.del calibrated to a sm.ller am.unt of data.

关键词： S-shaped yield criterion Coal pillar Back-analysis Num.rical m.deling