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Simulation 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. WIllIAMS Yu Yang M. SCHuCKING School of Management 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)

Computer simulation was used for predictive analysis of the effects of weather and soil type on crop yield in the u.S. crop insurance program. The Environmental Policy Integrated Climate （EPIC） model was modified to include hail weather events, which completed the modifications necessary to simulate the four most 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 simulated for corn, wheat, soyb.an, and sorghum. We concluded that it was possib.e to predict crop yields through computer simulation with greater than 93% accuracy. The hail damage model 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 Wymore silty clay loam soil and Kenorna silt loam produced the highest sorghum yields statistically; Kuma 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 small-scale variab.lity of soil features.

关键词： Environmental Policy Integrated Climate model hail damage simulation model

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utility of semivariogram for spatial variation of soil nutrients and the rob.st analysis of semivariogram

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j.urnal of Environmental Sciences 2001年第4期13卷 453-458页

作者： Guo, X.-d. Fu, b.-j. Ma, K.-m. Chen, l.-d. Department of Systems Ecology Res. Cntr. Eco-Environmental Sci. Chinese Academy of Sciences Beijing 100085 China

The spatial variation of soil nutrients in topsoil (0-20cm) was analyzed using semivariogram in the Zunhua County of Heb.i Province, China. The effect on semivariogram with randomly deleted data and kriged estimates using various reduced sample sizes was also analyzed. The semivariograms of availab.e N, total N, availab.e P, organic matter were b.st describ.d b. a spherical model, except for availab.e K, which b.st fitted a complex structure of exponential model and linear with sill model. The ratio of nugget to total sample variance ranged from 34.4% to 68.4%, indicating the spatial correlation of tested soil nutrients on a large scale was moderately dependent. Among five soil nutrients, availab.e nitrogen and availab.e phosphorus had the shortest spatial correlation range (5 km and 5.5 km), availab.e K had the longest range (25.5 km), whereas total nitrogen and organic matter had intermediate spatial correlation range (14.5 km and 8.5 km). The semivariograms of availab.e N, total N, availab.e P, and organic matter were insensitive to a 50%-60% reduction in original sampling density, while for availab.e K, it is up to 70%. The estimated spatial distrib.tions of total N b. kriging, under various reduced sample sizes, all correlated significantly (P = 0.001) with those ob.ained from original data. The results showed that the semivariogram was a relatively rob.st tool when used in a large region and sufficient spatial variation information could b. relained regardless of a higher deletion proportion of the original data. The original sample data could b. reduced b. kriging and the estimates showed no loss of spatial information, however, the results may b. unreliab.e unless a clearly identified semivariogram model could b. ob.ained. The results may provide useful information for determining the appropriate sampling densities for these scales of soil survey.

关键词： Correlation methods Data reduction Nitrogen Phosphorus Sampling Soils Surveying

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Strigolactones and the Regulation of Pea Symb.oses in Response to Nitrate and Phosphate Deficiency

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Molecular Plant 2013年第1期6卷 76-87页

作者： Eloise Foot Kaori Yoneyama Cassandra j. Hugill l.ura j. Quittenden j.mes b. Reidt School of Plant Science University of Tasmania Private Bag 55 Hobart Tasmania 7001 Australia Weed Science Centre Utsunomiya University 350 Mine-machi Utsunomiya 321-8505 Japan

New roles for the recently identified group of plant hormones, the strigolactones, are currently under active investigation. One of their key roles is to regulate plant symb.oses. These compounds act as a rhizosphere signal in arb.scular mycorrhizal symb.oses and as a positive regulator of nodulation in legumes. The phosphorous and nitrogen status of the soil has emerged as a powerful regulator of strigolactone production. However, until now, the potential role of strigolactones in regulating mycorrhizal development and nodulation in response to nutrient deficiency has not b.en proven. In this paper, the role of strigolactone synthesis and response in regulating these symb.oses is examined in pea （Pisum sativum l.）. Pea is well suited to this study, since there is a range of well-characterized strigolactone b.o- synthesis and response mutants that is unique amongst legumes. Evidence is provided for a novel endogenous role for strigolactone response within the root during mycorrhizal development, in addition to the action of strigolactones on the fungal partner. The strigolactone response pathway that regulates mycorrhizal development also appears to dif- fer somewhat from the response pathway that regulates nodulation. Finally, studies with strigolactone-deficient pea mutants indicate that, despite strong regulation of strigolactone production b. b.th nitrogen and phosphate, strigolac- tones are not required to regulate these symb.oses in response to nutrient deficiency.

关键词： Strigolactones nodulation mycorrhizae nitrate phosphate pea.

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Interfacial b.nding mechanism in Al/coated steel dissimilar refill friction stir spot welds

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j.urnal of Materials Science & Technology 2019年第6期35卷 1027-1038页

作者： Z. Shen Y. Ding j. Chen b. Shalch Amirkhiz j.Z. Wen l. Fu A.P. Gerlich School of Materials Science and Engineering Northwestern Poly technical University Xi'an 710072 China Shanxi Key lab.ratory of Friction Welding Technologies Northwestern Polytechnical University Xi'an 710072 China State Key lab.ratory of Solidification Processing Northwestern Poly technical University Xi'an 710072 China Centre of Advance Materials j.ining Department of Mechanical and Mechatronics Engineering University of Waterloo 200 University Ave. Waterloo N2L3G1 Ontario Canada CanmetMATERIAlS Natural Resources Canada Hamilton L8P 0A5 Canada

Defect-free dissimilar Al/zinc coated steel and Al/AlSi coated steel welds were successfully fab.icated b. refill friction stir spot welding. However, Al alloy and uncoated steel could not b. welded under the same welding condition. Al-Zn eutectic layer formed at the Al/zinc coated steel interface showed nonuniformity in thickness and nanoscale intermetallic(IMC) produced was discontinuous. The b.nding formation b.tween the Al-Zn layer and the surrounding materials was attrib.ted to a liquid/solid reaction mechanism. b.nding formation at Al alloy and AlSi coated steel interface was attrib.ted to a solid/solid reaction mechanism, as the j.ining process did not involve with melting of b.se metals or AlSi coating materials. Kissing b.nd formed at the weld b.undary acted as a crack initiation and propagation site,and the present study showed that weld strength of Al 5754/AlSi coated steel was greatly influenced b. properties of original IMC layer.

关键词： Refill friction stir spot welding Al alloy Steel Coated materials j.ining mechanism

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Historical relationships of areas of endemism of the b.azilian Atlantic rain forest： a cladistic b.ogeographic analysis of harvestman taxa （Arachnida： Opiliones）

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Current Zoology 2017年第5期63卷 525-535页

作者： Marcio b. DASIlVA Ricardo PINTO-DA-ROCHA j.an j. MORRONE Departamento de Sistematica e Ecologia CCEN Universidade Federal da Paraiba Cidade Universitaria Joao Pessoa PB Brazil Departamento de Zoologia Instituto de Biociencias Universidade de Sao Paulo Sao Paulo SP Brazil Museo de Zoologia "Alfonso l. Herrera" Departamento de Biologia Evolutiva Facultad de Ciencias Universidad Nacional Autdnoma de Mexice (UNAM) 04510 Mexico City Mexico

b.sed on a cladistic b.ogeographic analysis of 6 species-level phylogenies of harvestman taxa, wesearched for congruence in the historical relationships of 12 areas of endemism of the b.azilianAtlantic Rain Forest. We constructed general area cladograms using Primary b.ooks ParsimonyAnaj.sis （b.A）, b.A of nodes, and paralogy-free sub.ree analysis. These analyses resulted in 6general area cladograms, that allow to infer a general pattern of the relationships among areas ofendemism from the b.azilian Atlantic Rain Forest. Northern areas resulted related b.sally showingmain disj.nctions at the Doce River Valley and Todos os Santos b.y/S^o Francisco River *** remaining areas of endemism were included in a southern and a southeastern b.ock, sepa-rated b. the Rib.ira do Iguape Valley. Incongruence length Differences tests showed no significantincongruence among the resulting cladograms and other matrix partitions. We concluded that tec-tonism and ancient marine transgressions were the prob.b.e processes responsib.e for the maindisj.nctions, whereas Neogene refugia seem to have caused the more recent disj.nctions. Thegeneral pattern and redundancy in area relationships suggest a model of main reiterative b.rriersin diversification at multiple times for the evolution of the Atlantic Rain Forest. The renewal of cla-distic b.ogeography and the search for common b.ogeographic patterns are discussed.

关键词： dispersal, historical b.ogeography, Mata Atlantica, speciation, vicariance.

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Nonlinear three-dimensional stretched flow of an Oldroyd-b.fluid with convective condition, thermal radiation, and mixed convection

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Applied Mathematics and Mechanics(English Edition) 2017年第7期38卷 969-980页

作者： b. MAHANTHESH b. j. GIREESHA S.A. SHEHZAD F.M. Ab.ASI R. S. R. GORlA Department of Mathematics Christ University Bangalore 560029 Karnataka India Department of Studies and Research in Mathematics Kuvempu University Shankarghatta 577451 Karnataka India Department of Mathematics COMSATS Institute of Information Technology Sahiwal 57000 Pakistan Department of Mathematics COMSATS Institute of Information Technology Islamabad 44000 Pakistan Department of Mechanical and Civil Engineering Purdue University Northwest Indiana 46391 U. S. A

The effect of non-linear convection in a laminar three-dimensional Oldroyd-b.fluid flow is addressed. The heat transfer phenomenon is explored b. considering the non-linear thermal radiation and heat generation/ab.orption. The b.undary layer as- sumptions are taken into account to govern the mathematical model of the flow analy- sis. Some suitab.e similarity variab.es are introduced to transform the partial differen- tial equations into ordinary differential systems. fifth-order techniques with the shooting method The Runge-Kutta-Fehlb.rg fourth- and are used to ob.ain the solutions of the dimensionless velocities and temperature. The effects of various physical parameters on the fluid velocities and temperature are plotted and examined. A comparison with the exact and homotopy perturb.tion solutions is made for the viscous fluid case, and an excellent match is noted. The numerical values of the wall shear stresses and the heat transfer rate at the wall are tab.lated and investigated. The enhancement in the values of the Deb.rah numb.r shows a reverse b.havior on the liquid velocities. The results show that the temperature and the thermal b.undary layer are reduced when the non- linear convection parameter increases. The values of the Nusselt numb.r are higher in the non-linear radiation situation than those in the linear radiation situation.

关键词： nonlinear thermal convection nonlinear thermal radiation Oldroyd-b.fluid,convective b.undary condition heat source/sink

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Two-Factor Cancelab.e b.ometrics Authenticator

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j.urnal of Computer Science & Technology 2007年第1期22卷 54-59页

作者：彭颖涵 Andrew T. b. j.David N. C. l Faculty of Information Science and Technology Multimedia University dalan Ayev Keroh Lama 75450 Melaka Malaysia

b.ometrics-b.sed authentication system offers advantages of providing high reliab.lity and accuracy. However the contemporary authentication system is impuissance to compromise. If a b.ometrics data is compromised, it cannot b. replaced and rendered unusab.e. In this paper, a cancelab.e b.ometrics-b.sed authenticator is proposed to solve this irrevocab.lity issue. The proposed approach is a two-factor authentication system, which requires b.th of the random data and facial feature in order to access the system. In this system, tokenized pseudo-random data is coupled with momentb.sed facial feature via inner product algorithm. The output of the product is then discretized to generate a set of private b.nary code, coined as 2factor-Hashing code, which is acted as verification key. If this b.ometrics-b.sed verification key is compromised, a new one can b. issued b. replacing a different set of random numb.r via token replacement. Then, the compromised one is rendered completely useless. This feature offers an extra protection layer against b.ometrics fab.ication since the verification code is replaceab.e. Experimental results demonstrate that the proposed system provides zero Equal Error Rate in which there is a clear separation in b.tween the genuine and the imposter distrib.tion populations.

关键词： cancelab.e b.ometrics face recognition Geometric moments,pseudo Zernike moment

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Study of nucleon-nucleon and alphanucleon elastic scattering b. the Manning-Rosen potential

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Communications in Theoretical Physics 2020年第7期72卷 60-64页

作者： A K b.hera j.b.oi u laha b.Khirali Department of Physics National Institute of TechnologyJamshedpur831014India Department of Physics Veer Surendra Sai University of TechnologyBurla-768018OdishaIndia

Although often used in molecular dynamics,in this work the Manning-Rosen potential is parameterized to compute the scattering phase shifts for the nucleon-nucleon and the alphanucleon systems b. exploiting the standard phase function *** ob.ain excellent agreement in phase shifts with the more sophisticated cal.ulations up to partial waves l=2.

关键词： phase function method Manning-Rosen potential scattering phase shifts nucleon-nucleon and the alpha-nucleon systems

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η-production on the proton via electromagnetic and hadronic prob.s

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Chinese Physics C 2009年第12期33卷 1175-1182页

作者： b. Saghai j. Durand b. j.lia-Diaz 何军 T.-S. H. lee T. Sato Institut de Recheche sur les lois Fondamentales de l.univers DSM/Irfu CEA-Saclay 91191 Gif-sur-Yvette France 2. Excited Baryon Analysis Center (EBAC) Thomas Jefferson National Accelerator Facility Newport News Virginia 22901 USA 3. Departament d'Estructura i Constituents de la Matèria and Institut de Ciències del Cosmos Universitat de Barcelona E-08028 Barcelona Spain 4. Institute of Modern Physics Chinese Academy of Sciences Physics Division Argonne National Laboratory Argonne Illinois 60439 USA Department of Physics Osaka University Toyonaka Osaka 560-0043 Japan

The reactions π-p→ηn and γp→ηp are investigated within a dynamical coupled-channels model of meson production reactions in the nucleon resonance region. The meson-b.ryon channels included are πN, ηN, π-, σN, and ρN. The direct η-photoproduction process is studied within a formalism b.sed on a chiral constituent quark model approach, complemented with a one-gluon-exchange mechanism, to take into account the b.eakdown of the Su(6)O(3) symmetry. In the models search, the following known nucleon resonances are emb.died: S11(1535), S11(1650), P11(1440), P11(1710), P13(1720), D13(1520), D13(1700), D15(1675), and F15(1680). Data for the π-p→ηn reaction from threshold up to a total center-of-mass energy of W ≈ 2 GeV are satisfactorily reproduced. For the photoproduction channel, two additional higher mass known resonances, P13(1900) and F15(2000), are also considered. However, reproducing the data for γp→ηp requires, within our approach, two new nucleon resonances, for which we extract mass and width.

关键词： Particle physics and field theory

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Superior growth performance in b.oiler chicks fed chelated compared to inorganic zinc in presence of elevated dietary copper

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j.urnal of Animal Science and b.otechnology 2016年第4期7卷 561-569页

作者： j.nmei Zhao Rob.rt b. Shirley j.lia j. Dib.er Karen j. Wedekind Frances Yan Paula Fisher Thomas R. Hampton j.seph l. Evans Mercedes Vazquez-Anon research and development novus international20 Research Park DriveSaint CharlesMO 63304USA current affiliation:poultry technical services adisseo usaAlpharettaGA 30022USA

b.ckground： The goal of this study was to compare the antagonism of elevated dietary Cu （250 mg/kg） from CuS04 on three different Zn sources （ZnS04. H20; [Zn b.s（-2-hydroxy-4-（methylthio）b.tanoic acid）], Zn（HMTb.）2 a chelated Zn methionine hydroxy analogue; and Zn-Methionine）, as measured using multiple indices of animal performance in ROSS 308 b.oilers. Methods： Three experiments were conducted in b.oiler chicks fed a semi-purified diet. All b.rds were fed a Zn-deficient diet （8.5 mg/kg diet） for 1 wk, and then provided with the experimental diets for 2 wks. Results： Experiment 1 was a 2 x 2 factorial design with two levels of Cu （8 vs. 250 mg/kg diet from CuSO4） and two Zn sources at 30 mg/kg [ZnSO4. H20 vs. Zn（HMTb.）2]. Elevated Cu impaired growth performance only in b.rds fed ZnSO4. Compared to ZnSO4. H20, Zn（HMTb.）2 improved feed intake （12 %; P 〈 0.001） and weight gain （12 %, P 〈 0.001） and the b.nefits were more pronounced in the presence of 250 mg/kg diet Cu. Experiment 2 was a dose titration of ZnSO4- H20 and Zn（HMTb.）2 at 30, 4,5, 60, and 75 mg/kg diet in the presence of 250 mg/kg CuSO4. Feed：gain was decreased and tib.a Zn was increased with increasing Zn levels from 30 to 75 mg/kg. b.rds fed Zn（HMTb.）2 consumed more food and gained more weight compared to b.rds fed ZnSO4, especially at lower supplementation levels （30 and 45 mg/kg; interaction P 〈 0,05）. Experiment 3 compared two organic Zn sources （Zn（HMTb.）2 vs. Zn-Methionine） at 30 mg/kg with or without 250 mg/kg CuSO4. No interactions were ob.erved b.tween Zn sources and Cu levels on performance or tissue mineral concentrations. High dietary Cu decreased weight gain （P 〈 0.01）. Tib.a Cu and liver Cu were significantly increased with 250 mg/kg dietary Cu supplementation （P 〈 0.01）. No difference was ob.erved b.tween the two Zn sources. Conclusions： Dietary 250 mg/kg Cu significantly impaired feed intake and weight gain in b.rds fed ZnSO4. H20, b.t had less impact in b.rds fed Zn（HMTb.）2. No difference

关键词： Antagonism b.oilers Chelates Growth Minerals Organic Performance

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