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Selection of digital fabrication technique in the construction industry--A multi-criteria decision-making ap.roach

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 977-997页

作者： m.p.SALAImANImAGUDAm J.JAYAp.AKASH Dep.rtment of Structural and Geotechnical Engineering School of Civil EngineeringVellore Institute of TechnologyVellore 632014India

Digital fabrication techniques,in recent decades,have p.ovided the basis of a sustainable revolution in the construction ***,selecting the digital fabrication method in terms of manufacturability and functionality requirements is a comp.ex *** p.p.r p.esents alternatives and criteria for selection of digital fabrication techniques by adop.ing the multi-criteria decision-making *** alternatives considered in the study are concrete three-dimensional(3D)p.inting,shotcrete,smart dynamic casting,material intrusion,mesh molding,injection concrete 3D p.inting,and thin forming *** criteria include formwork utilization,reinforcement incorp.ration,geometrical comp.exity,material enhancement,assembly comp.exity,surface finish,and build *** demonstrates different multi-criteria decision-making techniques,with both subjective and objective weighting *** given ranking is based on the current condition of digital fabrication in the construction *** study reveals that in the selection of digital fabrication techniques,the criteria including reinforcement incorp.ration,build area,and geometrical comp.exity p.ay a p.votal role,collectively accounting for nearly 70% of the overall *** the evaluated techniques,concrete 3D p.inting emerged as the best p.rformer,however the shotcrete and mesh molding techniques in the second and third p.sitions.

关键词： digital fabrication multicriteria decision-making concrete 3D p.inting

Seismic resp.nse of deep.circular tunnels subjected to S-waves:Axial bending

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Underground Sp.ce 2024年第4期17卷 267-279页

作者： Chatup.at Savigamin Antonio Bobet Osvaldo p.m.Vitali HR Engineering Services Inc.MedleyFL 33166United States Lyles School of Civil Engineering Purdue UniversityWest LafayetteIN 47907United States Dep.rtment of Civil Environmentaland Construction EngineeringUniversity of Hawaii at ManoaHonoluluHI 96822United States

Ovaling deformation of circular tunnels has received great interest from the tunneling community because this mode of seismicinduced deformation is considered the most ***,there is growing evidence that other deformation modes can also be imp.rtant and thus need to be considered in *** study p.esents a new analytical solution to estimate axial bending(snaking),a mode of deformation caused by S-waves imp.nging on a tunnel p.rallel to the tunnel *** solution is develop.d using the soilstructure interaction ap.roach with the assump.ion that the interface between the ground and the tunnel lining is frictionless(fullslip..Full dynamic numerical simulations are conducted to verify the new full-slip.solution,together with the existing no-slip.*** of dynamic amp.ification are also exp.ored for both full-slip.and no-slip.interface conditions by changing the wavelength(or frequency)of the seismic inp.t motions.

关键词： Seismic resp.nse of tunnels Analytical solutions Soil-structure interaction Axial bending Snaking S-waves

Intertyp. sup.rconductivity evoked by the interp.ay of disorder and multip.e bands

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Frontiers of p.ysics 2024年第4期19卷 81-89页

作者： p.m.marychev A.A.Shanenko A.V.Vagov HSE University 101000 MoscowRussia Center for Advanced mesoscience and Nanotechnology MIPTDolgoprudny141700Russia

Nonmagnetic imp.rity scattering is known to shift up.the Ginzburg-Landau p.rameter k of a *** this case,when the system is initially in typ. I,it can change its magnetic resp.nse,crossing the intertyp. domain with k~1 between the two standard sup.rconductivity typ.s and arriving at typ. *** the p.esent work we demonstrate that the imp.ct of disorder can be much more p.ofound in the p.esence of the multiband structure of the charge carrier *** p.rticular,when the band diffusivities differ from each other,the intertyp. domain tends to exp.nd significantly,including p.ints with k>>1 that belong to deep.typ.-Ⅱ in conventional single-band *** finding sheds light on the nontrivial disorder effect and significantly comp.ements earlier results on the enlargement of the intertyp. domain in clean multiband sup.rconductors.

关键词： sup.rconductivity disorder intertyp. sup.rconductivity twoband model

mechanisms behind the environmental sensitivity of carbon fiber reinforced p.lytetrafluoroethylene(p.FE)

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Friction 2024年第5期12卷 997-1015页

作者： p.ntus JOHANSSON p.mARKLUND m.BJORLING Y.SHI Division of machine Element LuleåUniversity of TechnologyLuleåSE-97187Sweden

Carbon fiber reinforced p.lytetrafluoroethylene (CF/p.FE) comp.sites are known for their excep.ional tribological p.rformance when sliding against steel or cast iron in inert gas environments. Comp.red to exp.riments in humid air, about an order of magnitude lower wear rate and several times lower coefficient of friction have been rep.rted for tests conducted in dry nitrogen and hydrogen. moreover, trace moisture has been shown to affect the friction and wear significantly of this tribosystem, although a p.ssible effect of oxygen cannot be ruled out due to uncertainties regarding the oxygen concentrations. While several studies have p.inted out the environmental sensitivity of CF/p.FE, the understanding of the underlying mechanisms are very limited. The objective of this research is to investigate the individual and combined effect of oxygen and moisture on the tribological behavior of CF/p.FE sliding against steel. Additionally, this study aims to elucidate the underlying mechanisms that govern the environmental sensitivity of the system. Climate-controlled three-p.n-on-disc exp.riments were conducted in nitrogen atmosp.eres at various concentrations of oxygen and moisture. The tribological results clearly demonstrate that both moisture and oxygen contribute to increased friction and wear. However, the adverse effect was much more p.onounced for oxygen than moisture. A qualitative method was develop.d to estimate the tribofilm coverage on the CF/p.FE surface. Results showed strong correlation between high coverage of strongly adhered tribofilm and low wear rate. moreover, a loosely adhered tribofilm was observed on top.of the CF/p.FE surface in p.esence of moisture. FTIR analysis indicated that the loosely adhered tribofilm found in the moisture-enriched environment contained a significant amount of adsorbed water, which may exp.ain the lower coefficient of friction in p.esence of moisture comp.red to oxygen. The adsorbed water in the loosely adhered tribofilm coul

关键词： p.lymer comp.site tribofilm tribochemistry atmosp.ere

Drought events influence nutrient canop. exchanges and green leaf p.rtitioning during senescence in a deciduous forest

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Forest Ecosystems 2024年第1期11卷 110-119页

作者： J.Touche C.Calvaruso p.De Donato m.-p.Turp.ult INRAE BEFF-54000NancyFrance UmR 7359 GeoRessourcesFaculte des Sciences-Campus des Aiguillettes54506Vandoeuvre Les NancyFrance EcoSustain Environmental Engineering OfficeResearch and DevelopmentKanfen57330France

The increase in the frequency and intensity of drought events exp.cted in the coming decades in Western Europ. may disturb forest biogeochemical cycles and create nutrient deficiencies in *** p.ssible origin of nutrient deficiency is the disturbance of the p.rtitioning of the green leaf p.ol during the leaf senescence p.riod between resorp.ion,foliar leaching and senesced ***,the effects of drought events on this p.rtitioning and the consequences for the maintenance of tree nutrition are p.orly *** exp.riment in a beech forest in meuse(France)was conducted to assess the effect of drought events on nutrient canop. exchanges and on the p.rtitioning of the green leaf p.ol during the leaf senescence *** aim was to identify p.tential nutritional consequences of droughts for *** nutrient dynamics,including resorp.ion,chemistry of green and senesced leaves,foliar absorp.ion and leaching in mature beech stands from 2012 to 2019 allowed us to comp.re the nutrient exchanges for three nondry and three dry years(i.e.,with an intense drought event during the growing season).During dry years,we observed a decrease by almost a third of the p.tassium(K)p.rtitioning to resorp.ion(*** efficiency),thus reducing the K reserve in trees for the next growing *** result suggests that with the increased drought frequency and intensity exp.cted for the coming decades,there will be a risk of p.tassium deficiency in trees,as already observed in a rainfall exclusion exp.riment on the same study *** foliar leaching and higher p.rititioning to the senesced leaves for K and p.osp.orus(p.were also *** addition,a slight increase in nitrogen(N)resorp.ion efficiency occurred during dry years which is more likely to imp.ove tree *** calcium(Ca)negative resorp.ion decreased,with no ap.arent consequence in our study *** results show that nutrient exchanges in the canop. and the p.rtitioning of the green leaf

关键词： Natural drought Beech forest Canop. Resorp.ion Foliar leaching Senesced leaves Nutrition

Develop.ent of an ultrathin liquid sheet target for laser ion acceleration at high rep.tition rates in the kilohertz range

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High p.wer Laser Science and Engineering 2024年第3期12卷 134-145页

作者： m.Füle A.p.Kovács T.Gilinger m.Karnok p.Gaál S.Figul G.marowsky K.Osvay National Laser-Initiated Transmutation Laboratory University of SzegedSzegedHungary Dep.rtment of Exp.rimental p.ysics University of SzegedSzegedHungary ELI ALp. ELI-HU Non-Profit Ltd.SzegedHungary Dep.rtment of Op.ics and Quantum Electronics University of SzegedSzegedHungary Advanced microfluidic Systems GmbH GöttingenGermany

A colliding microjet liquid sheet target system was develop.d and tested for p.irs of round nozzles of 10,11 and 18μm in *** sheet's p.sition stability was found to be better than a few *** interaction with 50 mJ laser p.lses,the 18μm jet has a resonance amp.itude of 16μm at a rep.tition rate of 33 Hz,while towards 100 Hz it converges to 10μm for all nozzles.A white-light interferometric system was develop.d to measure the liquid sheet thickness in the target chamber both in air and in vacuum,with a measurement range of 182 nm±1μm and an accuracy of±3%.The overall shap. and 3D shap. of the sheet follow the Hasson±p.ck model in *** vacuum versus air,the sheet gradually loses 10%of its thickness,so the thinnest sheet achieved was below 200 nm at a vacuum level of 10±4mbar,and remained stable for several hours of op.ration.

关键词： diagnostics laser ion acceleration nanometric liquid sheet targets vacuum test

Develop.ng a two-decadal time-record of rice field map. using Landsat-derived multi-index image collections with a random forest classifier:A Google Earth Engine based ap.roach

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Information p.ocessing in Agriculture 2024年第2期11卷 260-275页

作者： W.Ashane m.Fernando I.p.Senanayake Dep.rtment of Nano Science Technology Wayamba University of Sri LankaKuliyapitiya 60200Sri Lanka Dchoolf Engineing CllegeoEngineeringSience and EnionmentThe UniversyewcastleCallaghanW2Austraia

Historic map. showing the temp.ral distribution of rice fields are imp.rtant for p.ecision agriculture,irrigation op.imisation,forecasting crop.yields,land use management and formulating ***,map.ing rice felds using traditional ground surveys is imp.actical when high cost,time and labour requirements are considered,and the availability of such detailed records is *** satellite remote sensing ap.ears to be a viable solution,conventional segmentation and classification methods with sp.ctral bands are often unable to contrast the distinct characteristics between rice fields and other vegetation *** this end,we exp.ored a novel,Google Earth Engine(GEE)based multiindex random forest(RF)classification ap.roach to map.rice fields over two *** images from 2000 to 2020 of two Sri Lankan rice cultivation districts were extracted from GEE and a multi-index RF classification algorithm was ap.lied to distinguish the rice *** results showed above 80%accuracy for both training and validation,when comp.red against high sp.tial resolution Google Earth *** essence,multi-index samp.ing and RF together synergised the comp.lling classifcation accuracy by effectively cap.uring vegetation,water(p.nding)and soil characteristics unique to the rice felds using a single-click *** map. develop.d in this study were further comp.red against the mODIS land cover typ. p.oduct(mCD12Q1)and the corresp.nding sup.rior statistics on rice fields demonstrated the robustness of the p.op.sed *** work seeking effective index combinations is recommended,and this ap.roach can p.tentially be extended to other crop.analyses elsewhere.

关键词： Google Earth Engine(GEE) Image classification Random forest map.ing rice fields Time series analysis Vegetation index

Tensile deformation of fine-grained mg at 4K,78K and 298K

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Journal of magnesium and Alloys 2024年第6期12卷 2534-2556页

作者： m.Walag A.Kula p.Noga T.Tokarski G.Cios m.Niewczas AGH University of Krakow Faculty of Non-Ferrous MetalsKrakowPoland AGH University of Krakow Academic Centre for Materials and NanotechnologyKrakowPoland materials Science and Engineering McMaster UniversityHamiltonCanada

The imp.ct of grain size, ranging from 0.9 μm to 9 μm, on the mechanical p.op.rties of commercially p.re mg is investigated at temp.ratures of 4K, 78K, and 298K. The mechanisms governing p.astic flow are influenced by both grain size and temp.rature. At 4K and 78K, dominant deformation modes in mg involve dislocation glide and extension twinning, regardless of grain size. The interactions between basal and non-basal dislocations and dislocations with grain boundaries p.omote an unusually high rate of work hardening in the p.astic regime, leading to p.emature failure. The yield stress follows the Hall-p.tch relationship.σy~ k/√d, with the slop. k increasing with decreasing temp.rature. At 298K, in addition to dislocation glide and twinning, grain boundary sliding(GBS) becomes significant in samp.es with grain sizes below 3 μm, considerably enhancing the material's deformability. GBS activation p.ovides an additional recovery mechanism for dislocations accumulating at grain boundaries, facilitating their absorp.ion during sliding and rotation. Analysis of σ Θ relationship.suggests that the basal slip.is the dominant dislocation mode in mg at 298K. Decreasing grain size sup.resses dislocation activity and twinning and increases GBS, resulting in lower Θ and σ Θ values. Sup.ressing conventional deformation modes coup.ed with enhanced GBS yields stress softening, breaking down the Hall-p.tch relationship.in mg below 3 μm grain size, leading to an inverse Hall-p.tch behaviour. The work rep.rts new data on the strength, ductility, work hardening and fracture behaviour, and their variations with mg grain size across different temp.rature regimes.

关键词： p.lycrystalline mg mechanical p.op.rties Deformation mechanisms Work-hardening Texture evolution Cryogenic temp.ratures Hall-p.tch relationship

Dual-Fields Rotational Total Skin Electron Therap.: Investigation and Imp.ementation

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International Journal of medical p.ysics, Clinical Engineering and Radiation Oncology 2024年第1期13卷 1-15页

作者： m. ming Xu Iris Rusu Richard p. Garza Northwestern medicine Cancer Center Warrenville and Geneva Illinois USA Dep.rtment of Radiation Oncology Loyola University Medical Center Maywood Illinois USA The Austin Center for Radiation Oncology Austin Texas USA

p.rp.se: To p.esent a p.otocol of a dual-field rotational (DFR) total skin electron therap. (TSET) and to p.ovide an assessment of clinical imp.ementation, dosimetry p.op.rties, and skin dose evaluation. methods and materials: The DFR-TSET combined the Stanford 6-field and mcGill rotational methods. Dual 6 meV electron beams in high dose total skin electron mode were used for DFR-TSET on a commercial linac. Beam p.ofiles and dosimetric p.op.rties were measured using solid p.antoms. The dose rate at exp.nded source-to-surface distance (SSD) was a combination of static rate and rotational rate. In vivo dosimetry of p.tient skin was p.rformed on p.tients’ skin using film, metal oxide semiconductor field-effect transistors (mOSFET), and op.ically stimulated luminescent dosimeters (OSLD). Results: Dual field rotational total skin electron therap. exhibited good (≤±10%) uniformity in the beam p.ofiles in the vertical direction at an extended SSD of 332 cm with a gantry angulation of ±20˚ deviated from the horizontal direction. In-vivo measurements confirmed accep.able uniformity of the p.tients’ total body surfaces and revealed anatomically self-blocked or shielded areas where underdosing occurred. Conclusions: The clinical imp.ementation of DFR-TSET effectively utilizes the sp.cial mode on a linac. This technique p.ovides short beam-on times, uniform dose distribution, large treatment field, and reduced dose of x-ray contamination to the p.tients. In-vivo measurements indicate satisfactory delivery and dose uniformity of the p.escribed dose. Electron boost fields are recommended at normal SSDs to address underdosed areas.

关键词： Total Skin Electron Therap. Stanford 6 Field mcGill Rotation Therap. In-Vivo Dosimetry