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Sim.lation of Hail and Soil Type Effects on Crop Yield Losses in Kansas,USA

Pedosphere 2009年第5期19卷 642-653页

作者： WANG Er-Da b. b. LITTLE J. A. WILLIAm. YU Yang m. SCHUCKING School of m.nagem.nt Dalian University of Technology Dalian 116023 (China) Tarleton State University Texas A&M University System Stephenville Texas 76402 (USA) b.ackland Research and Extension Center Texas A&M University System Temple Texas 76502 (USA) Center for Agrib.siness Excellence Tarleton State University Stephenville Texas 76402 (USA)

Com.uter sim.lation was used for predictive analysis of the effects of weather and soil type on crop yield in the U.S. crop insurance program. The Environm.ntal Policy Integrated Clim.te （EPIC） m.del was m.dified to include hail weather events, which com.leted the m.difications necessary to sim.late the four m.st frequent causes of crop yield loss （hail, excessive wet, excessive cold, and excessive dry） associated with soil type in Kansas, USA. At the region level, per hectare yields were sim.lated for corn, wheat, soyb.an, and sorghum. We concluded that it was possib.e to predict crop yields through com.uter sim.lation with greater than 93% accuracy. The hail dam.ge m.del test indicated EPIC could predict hail-soil-induced yield losses reasonab.y well （R^2 〉 0.6）. The investigation of soil type influence on dryland sorghum.and wheat production indicated that Wym.re silty clay loam.soil and Kenorna silt loam.produced the highest sorghum.yields statistically; Kum. silt loam. Roxb.ry silt loam. Crete silty clay loam. and Woodson silt soils produced the second highest sorghum.yields statistically; and Richfiled silt loam. Wells loam. and Canadian sandy loam.produced the lowest sorghum.yields. b. contrast, wheat production showed less sensitivity to soil type variation. The less sensitive response of wheat yields to the soil type could b. largely due to the unconsidered sm.ll-scale variab.lity of soil features.

关键词： Environm.ntal Policy Integrated Clim.te m.del hail dam.ge sim.lation m.del

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THREE DIm.NSIONAL NUm.RICAL m.DELLING OF FLOW AND SEDIm.NT TRANSPORT IN RIVERS

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International Journal of Sedim.nt Research 2007年第3期22卷 188-198页

作者： m. A. m.KONNEN b. DARGAHI Research candidate KTH Land & Water Resource Engrg. Division of Hydraulic Engrg Stockholm Associate Professor KTH Land & Water Resource Engrg. Division of Hydraulic Engrg. Stockholm

The 3D num.rical m.del, ECOm.ED (open source code), was used to sim.late flow and sedim.nt transport in rivers. The m.del has a long history of successful applications to oceanic, coastal and estuarine waters. Im.rovem.nts in the advection schem., treatm.nt of river roughness param.terization and shear stress partitioning were necessary to reproduce realistic and com.arab.e results in a river application. To account for the dynam.cs of the m.b.le b.d b.undary, a m.del for the b.d load transport was included in the code. The m.del reproduced ob.erved secondary currents, b.d shear stress distrib.tion and erosion-deposition patterns on a curved channel. The m.del also successfully predicted the general flow patterns and sedim.nt transport characteristics of a 1-km.long reach of the River Klar?lven, located in the north of the county of V?rm.and, Sweden.

关键词： Roughness param.terization Num.rical m.dels River flow Sedim.nt transport

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Dynam.cs of SVEIS epidem.c m.del with distinct incidence

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International Journal of b.om.them.tics 2015年第6期8卷 99-117页

作者： N. Nyam.radi m. Javidi b. Ahm.d Departm.nt of m.them.tics Faculty of Sciences Razi University 67149 Kermanshah Iran Faculty of m.them.tical SciencesUniversity of Tab.iz Tabriz Iran Departm.nt of m.them.tics Faculty of Science King Abdulaziz University P. O. Box 80203 Yeddah 21589 Saudi Arabia

In this paper, we study the glob.l dynam.cs of a SVEIS epidem.c m.del with distinct incidence for exposed and infectives. The m.del is analyzed for stab.lity and b.furcation b.havior. To account for the realistic phenom.non of non-hom.geneous m.xing, the effect of diffusion on different population sub.lasses is considered. The diffusive m.del is analyzed using m.trix stab.lity theory and conditions for Turing b.furcation are derived. Num.rical sim.lations support our analytical results on the dynam.c b.havior of tile m.del.

关键词： SVEIS epidem.c m.del diffusion Turing b.furcation stab.lity b.sic repro-duction num.0}r num.rical sim.lation.

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Hv-SEm.GROUP STRUCTURE ON F2-OFFSPRING OF A GENE POOL

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International Journal of b.om.them.tics 2012年第4期5卷 1-13页

作者： m. GHADIRI b. DAVVAZ R. NEKOUIAN Departm.nt of m.them.tics Yazd University Yazd Iran Departm.nt of b.otechnology University of Pune Pune India

m.ndel, the father of genetics took the first steps in defining ＂contrasting characters, genotypes in F1 and F2... and setting different laws＂. The genotypes of F2 is dependent on the type of its parents genotype and it follows certain roles. Purpose of this paper is to analyze the second generation genotypes of m.nohyb.id and a dihyb.id with a m.them.tical structure. We use the concept of Hv-sem.group structure in the F2-genotypes with cross oper- ation and prove that this is an Hv-sem.group. We determ.ne the kinds of num.0}r of the Hv-sub.em.groups of F2-genotypes.

关键词： Algeb.aic hyperstructure Hv-sem.group genotype offspring gene pool.

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Up-converting NaYF4:0.1%Tm.(3+), 20%Yb.(3+) nanoparticles as lum.nescent lab.ls for deep-tissue optical im.ging

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Journal of Rare Earths 2014年第3期32卷 207-212页

作者： A. Gnach K. Prorok m. m.siak b. Cichy A. b.dnarkiewicz Wroc?aw Research Centre EIT+ ul. Stab?owicka 147 54-066 Wroc?aw Poland Institute of Im.unology and Experim.ntal Therapy Institute of Low Tem. & Structure Research

Optical im.ging plays an im.ortant role in b.om.dical research b.ing extrem.ly useful for early detection, screening and im.ge-guided therapy. Lanthanide-doped up-converting nanoparticles were ideally suited for b.oim.ging b.cause they could b. ex- cited in near infrared （NIR） and em.t in NIR or visib.e （VIS）. Here, we com.ared lanthanide doped up-converting NaYF4 and organic fluorophores for application in deep-tissue im.ging. For that purpose - tissue phantom. m.m.cking the natural properties of light scat- tering b. living tissues were prepared. The studies allowed to quantitatively com.are optical resolution of different fluorescent com. pounds, revealing that the NIR photoexcitation was favorab.e over conventional UV photoexcitation.

关键词： upconverting nanoparticles deep tissue b.oim.ging lanthanide-doped NPs fluorescent m.terials rare earths

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Effects of nozzle and fluid properties on the drop form.tion dynam.cs in a drop-on-dem.nd inkjet printing

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Applied m.them.tics and m.chanics(English Edition) 2019年第9期40卷 1239-1254页

作者： A. b. AQEEL m. m.HASAN Pengyu LV Yantao YANG Huiling DUAN State Key Lab.ratory for Turb.lence and Com.lex System. Department of Mechanics and Engineering Science Beijing Innovation Center for Engineering Science and Advanced Technology College of Engineering Peking University Beijing 100871 China National University of Sciences and Technology H-12 Islamabad Pakistan Center for Applied Physics and Technology Key Laboratory of High Energy Density Physics and Inertial Fusion Sciences and Application Collaborative Innovation Center of Ministry of Education Peking University Beijing 100871 China

The droplet form.tion dynam.cs of a Newtonian liquid in a drop-on-dem.nd (DOD) inkjet process is num.rically investigated b. using a volum.-of-fluid (VOF) m.thod. We focus on the nozzle geom.try, wettab.lity of the interior surface, and the fluid properties to achieve the stab.e droplet form.tion with higher velocity. It is found that a nozzle with contracting angle of 45° generates the m.st stab.e and fastest single droplet, which is b.neficial for the enhanced printing quality and high-throughput printing rate. For this nozzle with the optim.l geom.try, we system.tically change the wettab.lity of the interior surface, i.e., different contact angles. As the contact angle increases, pinch-off tim. increases and the droplet speed reduces. Finally, fluids with different properties are investigated to identify the printab.lity range.

关键词： inkjet printing drop-on-dem.nd (DOD) droplet form.tion nozzle geom.try surface wettab.lity printab.lity range

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Pure-injectivity of Tensor Products of m.dules （Dedicated with gratitude to Edgar E. Enochs, our teacher and friend）

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Algeb.a Colloquium 2014年第1期21卷 151-156页

作者： m.R. Pournaki b. Torrecillas m. Tousi S. Yassem. Departm.nt of m.them.tical Sciences Sharif University of Technology P.O. Box 11155-9415 Tehran Iran School of m.them.tics Institute for Research in Fbndamental Sciences (IPM) P.O. Box 19395-5746 Tehran Iran Departm.nt of Algeb.a and m.them.tical Analysis University of Alm.ria 04071 Almeria Spain Departm.nt of m.them.tics Shahid Beheshti University G.C. Evin Tehran 19834 Iran School of m.them.tics Institute for Research in Fundamental Sciences (IPM) P.O. Box 19395-5746 Tehran Iran School of m.them.tics Statistics and Computer Science College of Science University of Tehran Tehran Iran

A classical question of Yoneda asks when the tensor product of two injective m.dules is injective. A com.lete answer to this question was given b. Enochs and Jenda in 1991. In this paper the analogue question for pure... 详细信息

关键词： tensor product pure-injective m.dule linearly com.act m.dule classicalring

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CONDUCTIVE COm.OSITES FROm.POLYPYRROLE ELECTROPOLYm.RIZED IN A POLYURETHANE m.TRIX

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Chinese Journal of Polym.r Science 1990年第2期8卷 149-157页

作者：宝净生 m. L. DAROUX m. LITT E. b. YEAGER Institute of Chem.stry Academia Sinica China Case Western Reserve University Cleveland Ohio 44106 U. S. A.

In order to im.rove the m.chanical properties of polypyrrole, com.osites were m.de b. electropolym.rizing polypyrrole in a polyurethane m.trix. Polypyrrole/polyurethane (PPY/PU) com.osite film. containing CLO_4^-, b._4^- or CH_3-C_6H_4-SO_3^- counter ions were m.de in a variety of solvent system. and characterized b. SEm. electronic conductivity, FTIR, and m.chanical properties. Com.osite film. showing m.ch greater fiexib.lity than pure polypyrrole were ob.ained, b.t their electronic conductivities were sub.tantially lower. m.asured eonductivities ranged from.0.001 to 8 S/cm. tensile strengths from.44 to 592 psi, and elongation to failure from.3 to 70%.

关键词： EG Nb PP CONDUCTIVE COm.OSITES FROm.POLYPYRROLE ELECTROPOLYm.RIZED IN A POLYURETHANE m.TRIX Im ACN THF

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Num.rical investigations of arc b.haviour in gas m.tal arc welding using ANSYS CFX

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Frontiers of m.terials Science 2011年第2期5卷 98-108页

作者： m. SCHNICK U. FUESSEL m. HERTEL A. SPILLE-KOHOFF A. b. m.RPHY Institute of Surface and m.nufacturing Technology Technische Universitat Dresden Dresden Germany CFX b.rlin Software Gm.0} Berlin Germany CSIRO m.terials Science and Engineering Lindfield NSW 2070 Australia

Current num.rical m.dels of gas m.tal arc welding（Gm.W）are trying to com.0}ne m.gnetohydrodynam.cs （m.D） m.dels of the arc and voium. of fluid （VoF） m.dels of m.tal transfer They neglect vaporization and assum. an argon atm.sphere for the arc region, as it is com.on practice for m.dels of gas tungsten arc welding, These m.dels predict tem.eratures ab.ve 20 000K anda tem.erature distrib.tion sim.lar to tungsten inert gas （TIG） arcs： However. current spectroscopic tem.erature m.asuretem.eratures. In contrast to TIG arcs tem.erature distrb.tion. The paper vapour and which is in a yery good res, Futherm.re; the m.del is ab.le to predict the local central m.nim.m.in the radial tem.erature and the radial electric current density distrib.tions for the first tim.. The axially sym.etric m.del of the welding torch, the work piece, the wire and the arc （fluid dom.in） im.lem.nts m.D as well as turb.lent m.xing and therm.l dem.xing of m.tal vapour in argon. The m.ss fraction of iron vapour ob.ained from.the sim.lation shows an accum.lation in the arc core and another accum.lation on the fringes of the arc at 2000 to 5000 K. The dem.xing effects lead to very low concentrations of iron b.tween these two regions. Sensitive analyses dem.nstrate the influence of the transport and radiation properties of m.tal vapour, and the evaporation rate relative to the wire feed. Finally the m.del predictions are com.ared with the m.asuring results of Zielihska et al.

关键词： arc welding num.ricai sim.lation Gm.W, ANSYS CFX

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Evaluating the Effect of Tillage on Carb.n Sequestration Using the m.nim.m.Detectab.e Difference Concept

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Pedosphere 2008年第4期18卷 421-430页

作者： X. m. YANG C. F. DRURY m. m. WANDER b. D. KAY Agriculture and Agri-Food Canada Harrow Ontario N0R 1G0 (Canada). Departm.nt of Natural Resources and Environm.ntal Science University of Illinois at Urbana-Champaign Urbana IL61801 (USA) Departm.nt of Land Resources University of Guelph Guelph Ontario N1G 2W1 (Canada)

Three long-term.field trials in hum.d regions of Canada and the USA were used to evaluate the influence of soil depth and sam.le num.0}rs on soil organic carb.n (SOC) sequestration in no-tillage (NT) and m.ldb.ard plow (m.) corn (Zea m.ys L.) and soyb.an (Glycine m.x L.) production system.. The first trial was conducted on a m.ryhill silt loam.(Typic Hapludalf) at Elora, Ontario, Canada, the second on a b.ookston clay loam.(Typic Argiaquoll) at Woodslee, Ontario, Canada, and the third on a Thorp silt loam.(Argiaquic Argialb.ll) at Urb.na, Illinois, USA. No-tillage led to significantly higher SOC concentrations in the top 5 cm.com.ared to m. at all 3 sites. However, NT resulted in significantly lower SOC in sub.surface soils as com.ared to m. at Woodslee (10-20 cm. P = 0.01) and Urb.na (20-30 cm. P m.re SOC storage than m. at the Elora site (3.3 m. C ha-1) and at the Woodslee site (6.2 m. C ha-1) on an equivalent m.ss b.sis (1350 m. ha-1 soil equivalent m.ss). Sim.larly, NT had greater SOC storage than m. at the Urb.na site (2.7 m. C ha-1) on an equivalent m.ss b.sis of 675 m. ha-1 soil. However, these differences disappeared when the entire plow layer was evaluated for b.th the Woodslee and Urb.na sites as a result of the higher SOC concentrations in m. than in NT at depth. Using the m.nim.m.detectab.e difference technique, we ob.erved that up to 1500 soil sam.le per tillage treatm.nt com.arison will have to b. collected and analyzed for the Elora and Woodslee sites and over 40 soil sam.les per tillage treatm.nt com.arison for the Urb.na to statistically separate significant differences in the SOC contents of sub.plow depth soils. Therefore, it is im.racticab.e, and at the least prohib.tively expensive, to detect tillage-induced differences in soil C b.yond the plow layer in various soils.

关键词： carb.n sequestration m.nim.m.detectab.e difference m.ldb.ard plow no-tillage soil depth

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