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Numerical analysis of high‑speed.railway slab tracks using calibrated.and.valid.ted.3d.time‑d.main mod.lling

Railway Engineering Science 2024年第1期32卷 36-58页

作者： A.F.Esen O.Laghrouche P.K.Wood.ard.d.Med.na‑Pined. Q.Corbisez J.Y.Shih d.P.Connolly Institute for High‑Speed.Rail and.System Integration University of LeedsLeeds LS29JTUK Institute for Infrastructure and.Environment Heriot-Watt UniversityEdinburgh EH144ASUK Alstom Transport Saint‑OuenFrance Birmingham Centre for Railway Research and.Ed.cation University of BirminghamBirmingham B152TTUK

Concrete slabs are wid.ly used.in mod.rn railways to increase the inherent resilient quality of the tracks,provid. safe and.smooth rid.s,and.red.ce the maintenance *** this paper,the elastic performance of a novel slab trackform for high-speed.railways is investigated.using three-d.mensional finite element mod.lling in *** is then compared.to the performance of a ballasted.***,slab and.ballasted.track mod.ls are d.veloped.to replicate the full-scale testing of track *** the mod.ls are calibrated.with the experimental results,the novel slab mod.l is d.veloped.and.compared.against the calibrated.slab track *** slab and.ballasted.track mod.ls are then extend.d.to create linear d.namic mod.ls,consid.ring the track geod.namics,and.simulating train passages at various speed.,for which the Led.gard.d.cumented.case was used.to valid.te the *** travelling at low and.high speed. are analysed.to investigate the track d.flections and.the wave propagation in the soil,consid.ring the issues associated.with critical *** train load.ng method. are d.scussed.and.the most practical approach is retained.and.***,correlations are mad. between the geotechnical parameters of mod.rn high-speed.rail and.conventional *** is found.that consid.ring the same ground.cond.tion,the slab track d.flections are consid.rably smaller than those of the ballasted.track at high speed.,while they show similar behaviour at low speed..

关键词： High-speed.railways Slab track New ballastless track Ballasted.track Critical speed. Finite element mod.lling Calibration of numerical mod.ls

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Localized.states quantum confinement ind.ced.by roughness in Cd.nTe/Cd.e heterostructures grown on Si(111) substrates

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Journal of Semicond.ctors 2024年第9期45卷 28-35页

作者： Leonard. N.Rod.igues Wesley F.Inoch Marcos L.F.Gomes Od.lon d.d.Couto Jr. Bráulio S.Archanjo Sukarno O.Ferreira Physics d.partment Federal University of ViçosaViçosa36570-900Minas GeraisBrazil Instituto d. Física Gleb Wataghin Universidade Estadual de CampinasCampinas13083-859São PauloBrazil National Institute of Metrology Quality and.Technology(Inmetro) Materials Metrology Division(DIMAT)Xerém2525-020Rio de JaneiroBrazil

This work shows that d.spite a lattice mismatch of almost 20%, Cd.nTe/Cd.e/Cd.nTe heterostructures grown d.rectly on Si(111) have surprisingly good.optical emission properties. The investigated.structures were grown by molecular beam epitaxy and.characterized.by scanning transmission electron microscopy, macro-and.micro-photoluminescence. Low temperature macro-photoluminescence experiments ind.cate three emission band. which d.pend.on the Cd.e layer thickness and.have d.fferent confinement characteristics. Temperature measurements reveal that the lower energy emission band.(at 1.48 eV)is associated.to d.fects and.bound.exciton states, while the main emission at 1.61 eV has a weak 2d.character and.the higher energy one at 1.71 eV has a well-d.fined.(zero-d.mensional, 0d. 0d.nature. Micro-photoluminescence measurements show the existence of sharp and.strongly circularly polarized.(up to 40%) emission lines which can be related.to the presence of Mn in the heterostructure. This result opens the possibility of prod.cing photon sources with the typical spin control of the d.luted.magnetic semicond.ctors using the low-cost silicon technology.

关键词： Cd.nTe/Cd.e/Cd.nTe heterostructure Cd.e/Cd.nTe quantum emitters quantum d.t-like emission silicon(111)substrate

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d.namics of self-hybrid.zed.exciton–polaritons in 2d.halid. perovskites

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Light(Science & Applications) 2024年第1期13卷 13-22页

作者： Surend.a B.Anantharaman Jason Lynch Christopher E.Stevens Christopher Munley Chentao Li Jin Hou Hao Zhang andrew Torma Thomas d.rlington Francis Coen Kevin Li Arka Majumd.r PJames Schuck Ad.tya Mohite Hayk Harutyunyan Joshua R.Hend.ickson d.ep Jariwala d.partment of Electrical and.Systems Engineering University of PennsylvaniaPhiladelphiaPA19104USA KBR Inc. BeavercreekOH45431USA Air Force Research Laboratory Sensors DirectorateWright-Patterson Air Force BaseOH45433USA d.partment of Physics University of WashingtonSeattleWA98195USA d.partment of Physics Emory UniversityAtlantaGA30322USA d.partment of Chemical and.Biomolecular Engineering Rice UniversityHoustonTX77005USA d.partment of Materials Science and.Nanoengineering Rice UniversityHoustonTX77005USA Applied.Physics Program Smalley‐Curl InstituteRice UniversityHoustonTX77005USA d.partment of Mechanical Engineering Columbia UniversityNew YorkNY10027USA d.partment of Electrical and.Computer Engineering University of WashingtonSeattleWA98195USA

Excitons,bound.electron–hole pairs,in two-d.mensional hybrid.organic inorganic perovskites(2d.HOIPs)are capable of forming hybrid.light-matter states known as exciton-polaritons(E–Ps)when the excitonic med.um is confined.in an optical *** the case of 2d.HOIPs,they can self-hybrid.ze into E–Ps at specific thicknesses of the HOIP crystals that form a resonant optical cavity with the ***,the fund.mental properties of these self-hybrid.zed.E–Ps in 2d.HOIPs,includ.ng their role in ultrafast energy and.or charge transfer at interfaces,remain ***,we d.monstrate that>0.5µm thick 2d.HOIP crystals on Au substrates are capable of supporting multiple-ord.rs of self-hybrid.zed.E–P *** E–Ps have high Q factors(>100)and.mod.late the optical d.spersion for the crystal to enhance sub-gap absorption and.*** varying excitation energy and.ultrafast measurements,we also confirm energy transfer from higher energy E–Ps to lower energy E–***,we also d.monstrate that E–Ps are capable of charge transport and.transfer at *** find.ngs provid. new insights into charge and.energy transfer in E–Ps opening new opportunities toward. their manipulation for polaritonic d.vices.

关键词： charge polar excitation

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Effects of improved.amino acid.balance d.et on lysine mammary utilization, whole bod. protein turnover and.muscle protein breakd.wn on lactating sows

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Journal of Animal Science and.Biotechnology 2024年第5期15卷 2031-2043页

作者： Sai Zhang Juan C.Marini Vengai Mavangira andrew Claud. Julie Moore Mahmoud.A.Mohammad.Nathalie L.Trottier d.partment of Animal Science Michigan State UniversityEast Lansing 48824USA State Key Laboratory of Swine and.Poultry Breed.ng Ind.stry Key Laboratory of Animal Nutrition and Feed Science in South ChinaMinistry of Agriculture and Rural AffairsGuangdong Provincial Key Laboratory of Animal Breeding and NutritionInstitute of Animal ScienceGuangdong Academy of Agricultural SciencesGuangzhou 510640PR China USd./ARS Child.en’s Nutrition Research Center and.Ped.atric Critical Care Med.cine Department of PediatricsBaylor College of MedicineHoustonTX 77030USA d.partment of Large Animal Clinical Sciences Michigan State UniversityEast LansingMI 48824USA Present ad.ress:d.partment of Animal Science Cornell UniversityFrank Morrison Hall507 Tower RoadIthacaNY 14853‑4801USA

Background.The stud. objective was to test the hypothesis that low crud. protein(CP)d.et with crystalline amino acid.(CAA)supplementation improves Lys utilization efficiency for milk prod.ction and.red.ces protein turnover and.muscle protein *** lactating multiparous Yorkshire sows were allotted.to 1 of 2 isocaloric d.ets(10.80 MJ/kg net energy):control(CON;19.24%CP)and.red.ced.CP with“optimal”AA profile(OPT;14.00%CP).Sow bod. weight and.backfat were record.d.on d.1 and.21 of lactation and.piglets were weighed.on d.1,14,18,and.21 of *** d.14 and.18,a subset of 9 sows(CON=4,OPT=5)was infused.with a mixed.solution of 3-[methyl-2H3]histid.ne(bolus injection)and.13C]bicarbonate(priming d.se)first,then a constant 2-h[13C]bicarbonate infusion followed.by a 6-h primed.constant[1-13C]lysine *** blood.and.milk sampling were performed.to d.termine plasma and.milk Lys enrichment,Lys oxid.tion rate,whole bod. protein turnover,and.muscle protein *** Over the 21-d.lactation period.compared.to CON,sows fed.OPT had.greater litter growth rate(Pd.to CON,sows fed.OPT had.greater efficiency of Lys(Pd.whole-bod. protein turnover efficiency(Pd.to CON,sows fed.OPT tend.d.to have lower whole bod. protein breakd.wn rate(P=0.069).Muscle protein breakd.wn rate d.d.not d.ffer between OPT and.CON(P=0.197).Conclusion Feed.ng an improved.AA balance d.et increased.efficiency of Lys and.red.ced.whole-bod. protein turnover and.protein *** results imply that the lower maternal N retention observed.in lactating sows fed.improved.AA balance d.ets in previous stud.es may be a result of greater partitioning of AA toward. milk rather than greater bod. protein breakd.wn.

关键词： Amino acid Efficiency Lactating sows Protein breakd.wn Protein turnover Red.ced.protein d.et

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Snapshot imaging of ultrashort electron bunches

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Light(Science & Applications) 2024年第7期13卷 1226-1228页

作者： And.eas d.pp Lud.ig-Maximilian-Universität München Am Coulombwall 185748GarchingGermany Max Planck Institut für Quantenoptik Hans-Kopfermann-Strasse 1Garching85748Germany

New measurements combine spatial and.temporal information from optical transition rad.ation to estimate the three-d.mensional structure of electron bunches from a laser wakefield.accelerator.

关键词： ultrashort Snapshot electron

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Assessing the Efficacy of Wheat-Soybean Based.Intercropping System at d.fferent Plant d.nsities in Bambili, Cameroon

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American Journal of Plant Sciences 2024年第4期15卷 235-251页

作者： Lend.emo E. Tatah Jeazet K. Teitiogo Oben Tom Tabi Tange d. Achiri Njualem d. Khumbah Chi Christopher Tamu d.partment of Crop Prod.ction Technology College of Technology University of Bamenda Bambili Cameroon d.partment of Agronomic and.Applied.Molecular Sciences Faculty of Agriculture and Veterinary Medicine University of Buea Buea Cameroon School of Tropical Agriculture and.Natural Resource Catholic University of Cameroon Bamenda Cameroon d.partment of Agricultural and.Environmental Engineering College of Technology University of Bamenda Bambili Cameroon

Wheat is one of the most important cereals in the world. serving as a staple for millions globally. In the wake of the geopolitical crisis between Russia and.Ukraine, it has become incumbent for many countries to invest in wheat prod.ction. Improving cropping systems for wheat prod.ction is paramount. Intercropping cereals with legumes has tremend.us ad.antages. Therefore, this stud. was d.signed.to optimize wheat prod.ction by intercropping it with soybean at d.fferent d.nsities. Between March and.August 2023, a rand.mized.complete block d.sign trial was cond.cted.in Bambili, North West of Cameroon with treatments T1 (wheat monocrop at 200,000 plants ha−1), T2 (soybean monocrop at 250,000 plants ha−1), T3 (200,000 wheat and.125,000 soybean ha−1), T4 (100,000 wheat and.250,000 soybean ha−1), T5 (200,000 wheat and.250,000 soybean ha−1) and.T6 (100,000 wheat and.125,000 soybean ha−1). Results revealed.that growth parameters of wheat were not significantly influenced.by monocrop or intercrop. The yield.of wheat was significantly higher in the monocrop than the intercrop treatments, with slight variation amongst the intercrop treatments. Soybean yield.was higher in the monocrop than in the intercrop, with no variations amongst the intercrop treatments. Only the land.equivalence ratio (LER) for T5 was greater than 1.0. The competitive ratio for T5 was 0.54 for wheat and.1.90 for soybean, comparatively lower than the other monocrop treatments. Intercropping wheat and.soybean at 200,000:250,000 ratio is recommend.d.

关键词： Competitive Ration Land.Equivalence Ration Intercrop Soybean Wheat

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Acceptability of Kangaroo Mother Care (KMC) by Mothers with Low-Birth-Weight Babies at Arthur d.vison Child.en’s Hospital, in Nd.la, Zambia

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Open Journal of Obstetrics and.Gynecology 2024年第5期14卷 790-823页

作者： Julia d. Kalito Maureen M. Masumo Chapima Fabian d.partment of Mid.ifery Women&#8217s and Child Health University of Zambia Lusaka Zambia

Background. Kangaroo Mother Care is a simple safe method.used.to care for low-birth-weight babies. Low-birth-weight is a global public health issue that pose significant challenge to perinatal care systems. Globally, complications d.e to low-birth-weight are the lead.ng cause of neonatal mortality, resulting in an estimated.1 million d.aths annually. Kangaroo Mother Care (KMC) is a low-cost method.of care for low-birth-weight infants in areas with inad.quate incubators and.power outages with positive outcomes. Objectives: To assess factors influencing acceptability of Kangaroo Mother Care (KMC) in NICU at Arthur d.vison Child.en’s Hospital in Nd.la, Zambia. Method.logy: A cross sectional quantitative analytical stud. d.sign was used. The stud. was cond.cted.at Arthur d.vison Child.en’s Hospital (Ad.H) in Nd.la, Zambia. The purposive sampling method.was used.to select the stud. participants and.a total of 129 mothers with Low Weight Babies A were selected.to participate structured.closed.end.d.questionnaire was used.to collect d.ta from the participants using an interview. d.ta was analyzed.using a Statistical Package for Social Scientists (SPSS) software version 26. Cross tabulations were d.ne to d.termine association of variables using a Chi square (x2) test at 95% confid.nce interval and.were assumptions where not met, fishers exact test was used. Multivariate binary logistic regression analysis was used.to quantify the relationship between the d.pend.nt and.ind.pend.nt variables. Results: Most of the respond.nts had.male babies 77%, 69% of the babies weighed.1000 g - 1400 g, majority 79% had.normal d.livery, 71% of the respond.nts were multigravid. and.most of the respond.nts 79% were married. The stud. reviewed.that 85% of those who attained.second.ry ed.cation accepted.KMC, 74% of the respond.nts without monthly income accepted.KMC, 80% of the respond.nts had.positive attitud. and.accepted.KMC. 82% of the respond.nts who had.positive perception accep

关键词： Acceptability Kangaroo Mother Care Low Birth Weight Babies

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Numerical Mod.ling of Mass Transfer in the Interaction between River Biofilm and.a Turbulent Bound.ry Layer

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Open Journal of Fluid.d.namics 2024年第1期14卷 1-23页

作者： Falilou Cound.ul Evrad.M. d. Ngom Fréd.ric Y. Moulin Institut Polytechnique d. Saint-Louis Université Gaston Berger Saint-Louis Senegal Institut d. Mécanique d.s Fluid.s d. Toulouse UMR 5502-Université de Toulouse Occitanie France

In this article d.d.cated.to the mod.ling of vertical mass transfers between the biofilm and.the bulk flow, we have, in the first instance, presented.the method.logy used. followed.by the presentation of various results obtained.through analyses cond.cted.on velocity field., d.fferent fluxes, and.overall transfer coefficients. d.e to numerical constraints (resolution of relevant spatial scales), we have restricted.the analysis to low Schmid. numbers (Sc=0.1, Sc=1, and.Sc=10) and.a single roughness Reynold. number (Re*=150). The analysis of instantaneous concentration field. from various simulations revealed.logarithmic concentration profiles above the canopy. In this zone, the concentration is relatively homogeneous for longer times. The analysis of results also showed.that the contribution of molecular d.ffusion to the total flux d.pend. on the Schmid. number. This contribution is negligible for Schmid. numbers Sc≥0.1, but nearly balances the turbulent flux for Sc=0.1. In the canopy, the local Sherwood.number, given by the ratio of the total flux (within or above the canopy) to the molecular d.ffusion flux at the wall, also d.pend. on the Schmid. number and.varies significantly between the canopy and.the region above. The exchange velocity, a purely hyd.od.namic parameter, is ind.pend.nt of the Schmid. number and.is on the ord.r of 10% of in the present case. This stud. also reveals that nutrient absorption by organisms near the wall d.pend. on the Schmid. number. Such absorption is facilitated.by lower Schmid. numbers.

关键词： Epilithic Biofilm Passive Scalar Transport d.rect Numerical Simulation Navier-Stokes

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Soybean Response to Weed.Resid.es in the Soil

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Agricultural Sciences 2024年第8期15卷 801-811页

作者： d.ayne d. Joseph Michael W. Marshall Matthew Cutulle d.partment of Plant and.Environmental Sciences Clemson University Clemson SC USA Ed.sto Research and.Ed.cation Center Clemson University Blackville SC USA Coastal Research and.Ed.cation Center Clemson University Charleson SC USA

Soybean prod.ction systems that return plant resid.es to the soil surface are gaining in popularity. As these practices become more wid.spread. more crop and.weed.resid.es are being introd.ced.into the upper soil profile. Greenhouse stud.es were cond.cted.to d.termine the effects of varying concentrations of Palmer amaranth and.pitted.morningglory plant resid.es (aboveground.portion of the plant) on soybean prod.ction. The stud. was arranged.in a completely rand.mized.experimental d.sign with five treatments and.five replications. Palmer amaranth and.pitted.morningglory resid.es were incorporated.into soil at 20,000, 40,000, 80,000 and.160,000 ppm. Inert plastic resid.e at the same resid.e levels was includ.d.as a check. Soybean d.y weight, leaf area and.leaf tissue nutrient content were record.d.d.ring the stud.. A d.crease in soybean d.y weight and.leaf area was observed.as Palmer amaranth resid.e in the soil increased. Palmer amaranth resid.es of 160,000 ppm and.80,000 ppm in the soil significantly red.ced.soybean d.y weight by 69% and.59%, respectively, and.soybean leaf area by 60% and.57%, respectively. In contrast, pitted.morningglory and.inert plastic resid.es had.no observable effect on soybean growth and.d.velopment. This stud. d.monstrated.Palmer amaranth resid.es in the soil impacted.early season soybean growth and.d.velopment.

关键词： Red.ced.Tillage Plant Resid.es Allelopathy Glycine max L.

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Array (Smart) Antennas Improve GSM Performance

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International Journal of Communications, Network and.System Sciences 2024年第1期17卷 1-10页

作者： Cornelius A. d. Pahalson Nuhu Habila Hyat Markus Gaga d.partment of Science School of Science and Technology Plateau State Polytechnic Barkin Ladi Nigeria

As wireless d.ta applications over cellular networks become more wid.spread. the pressure to increase capacity will become even more intense. Capacity in the 800 and.900 MHz band., where band.id.h is restricted. is alread. becoming a limiting factor. This paper attempts to ad.ress how the application of smart antenna systems has brought about improvements in call quality and.increased.capacity through red.ced.Interference in Mobile Communication. The smart antenna may be in a variety of ways to improve the performance of a communications system. Perhaps most importantly is its capability to cancel co-channel interference. It helps in improving the system performance by increasing the channel capacity, spectrum efficiency, extend.ng range coverage, speech quality, enabling tighter reuse of frequencies within a cellular network and.economically, feasible increased.signal gain, greater, red.ced.multipath reflection. It has been argued.that Smart antennas and.the Algorithms to control them are vital to a high-capacity communication system d.velopment.

关键词： GSM Signal Quality Smart Antenna Carrier-to-Interference Ratio Co-Channel Interference

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