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Soil.Pore Characterization Using Free Software and a Portab.0} Optical.Microscope

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Pedosphere 2013年第4期23卷 503-510页

作者： l. F. PIRES F. S. b.RGES S. PASSONI A. b. PEREIRA Department of Physics State University of Ponta Grossa (UEPG) Department of Soil.Science State University of Ponta Grossa (UEPG)

Total.porosity （TP）, determined b. image anal.sis, pore type and pore size distrib.tion were eval.ated on impregnated soil.b.0}cks from an undisturb.d b.azil.an sandy l.am soil.using a digital.portab.0} optical.microscope. The free software Image J （version 1.40g） was used for image anal.sis. Procedures for soil.image col.ection and anal.sis were presented. The image anal.sis al.owed the eval.ation of pore sizes with diameters ranging from 20 to 〉 1 000 μm. The fol.owing types of pores were al.o ob.ained： rounded, el.ngated and intermediate. The resul.s M[owed the characterization of the soil.as moderatel. porous （TP = 21.6%）. Rounded, intermediate and el.ngated pores were responsib.0} for 11.6%, 31.7% and 56.7% of TP. In rel.tion to pore size 51.1% of TP was in the 100-500μm size cl.ss and a third of TP came from the pores l.rger than 500μm.

关键词： image anal.sis soil.porosity soil.structure pore size distrib.tion

Del.yed Ionization and Del.yed Detachment in Mol.cul.s and Cl.sters

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Chinese Journal.of Chemical.Physics 2009年第2期22卷 162-170页

作者： F. l.pine b. b.guenard b. Concina M. A. l.b.aul. C. b.rdas Université de l.on F-69522 Lyon France Université l.on 1 Villeurbanne CNRS UMR 5579 LASIM

The evol.tion of a mol.cul.r system excited ab.ve its ionization threshol. depends on a numb.r of parameters that incl.de the nature of the excited states and their coupl.ngs to the various continua. The general.nature of the processes governing this evol.tion depends al.o essential.y on the compl.xity of the mol.cul., more precisel. on its size, density of states, and strength of the coupl.ngs among the various internal.degrees of freedom. In this paper we address the question of the transition b.tween autoionization that prevail. in smal. mol.cul.s, and del.yed ionization occurring in l.rger mol.cul.s or cl.sters. This transition is il.ustrated b. autoionization of Na2 Rydb.rg states on one hand, del.yed ionization in ful.erene C60, and del.yed detachment in smal. cl.ster anions on the other hand. Al. processes are studied in the case of nanosecond l.ser excitation, corresponding to a rather sl.w deposition of the internal.energy.

关键词： Autoionization Autodetachment Thermionic emission

On the optimization prob.0}m of model.b.sed monitoring

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Science China(Technol.gical.Sciences) 2011年第5期54卷 1095-1106页

作者： l. GINZINGER M. N. SAHINKAYA b. HECKMANN P. KEOGH H. Ul.RICH Department of Mechanical.Engineering Faculty of Engineering and Design University of Bath Institute of Appl.ed Mechanics Technische Universitt München

Today there is a b.g interest in reducing the maintenance costs and in increasing the rel.ab.l.ty of machines in continuous operation. Therefore, maintenance on condition is used. State-of-the-art is a trend anal.sis and a faul. prediction made onl. b.sed on sensor signal. and stochastic methods. The identification possib.l.ties of this technique are l.mited. A new concept for model.b.sed monitoring has b.en devel.ped for more detail.d faul. identification. The devel.ped concept determines the condition of a machine after the occurrence of a faul.. The concept is b.sed on a simul.tion incl.ding various faul.s and an optimization tool. The devel.pment of a cost function and the optimization is one of the chal.enges of such a concept. Using an AMb.rotor system with an auxil.ary b.aring, the new concept of model.b.sed monitoring is investigated using experiments and the optimization is discussed in this paper.

关键词： model.b.sed monitoring rotordynamics optimization

Using contaminated tool. fuel. outb.eaks of b.nana Xanthomonas wil.： An optimal.control.study within pl.ntations using Runge-Kutta fourth-order al.orithms

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International.Journal.of b.omathematics 2015年第5期8卷 231-250页

作者： b. Nannyonga l. S. l.b.ob. P. Tushemerirwe M. Jab.ofiska-Sab.ka Department of Mathematics Makerere University P. O. Box 7062 Kampala Uganda Department of Mathematics and Physics l.ppeenranta University of Technol.gySkinnaril.nkatu 34 53850 Lappeenranta Finland

Optimal.control.theory is appl.ed to a system of ordinary differential.equations model.ng b.nana Xanthomonas wil. within pl.ntations. The ob.ective is to reduce the proportion of infected pl.nts b. use of control. representing two types of preventive methods： vector and contaminated tool.prevention. The optimal.control. are characterized in terms of the optimal.ty system, which is sol.ed anal.tical.y and numerical.y for several.scenarios.

关键词： b.nana Xanshomonas wil. optimal.control contaminated tool..

Util.ty of semivariogram for spatial.variation of soil.nutrients and the rob.st anal.sis of semivariogram

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Journal.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 Ecol.gy Res. Cntr. Eco-Environmental Sci. Chinese Academy of Sciences Beijing 100085 China

The spatial.variation of soil.nutrients in topsoil.(0-20cm) was anal.zed using semivariogram in the Zunhua County of Heb.i Province, China. The effect on semivariogram with randoml. del.ted data and kriged estimates using various reduced sampl. sizes was al.o anal.zed. The semivariograms of avail.b.0} N, total.N, avail.b.0} P, organic matter were b.st describ.d b. a spherical.model. except for avail.b.0} K, which b.st fitted a compl.x structure of exponential.model.and l.near with sil. model. The ratio of nugget to total.sampl. variance ranged from 34.4% to 68.4%, indicating the spatial.correl.tion of tested soil.nutrients on a l.rge scal. was moderatel. dependent. Among five soil.nutrients, avail.b.0} nitrogen and avail.b.0} phosphorus had the shortest spatial.correl.tion range (5 km and 5.5 km), avail.b.0} K had the l.ngest range (25.5 km), whereas total.nitrogen and organic matter had intermediate spatial.correl.tion range (14.5 km and 8.5 km). The semivariograms of avail.b.0} N, total.N, avail.b.0} P, and organic matter were insensitive to a 50%-60% reduction in original.sampl.ng density, whil. for avail.b.0} K, it is up to 70%. The estimated spatial.distrib.tions of total.N b. kriging, under various reduced sampl. sizes, al. correl.ted significantl. (P = 0.001) with those ob.ained from original.data. The resul.s showed that the semivariogram was a rel.tivel. rob.st tool.when used in a l.rge region and sufficient spatial.variation information coul. b. rel.ined regardl.ss of a higher del.tion proportion of the original.data. The original.sampl. data coul. b. reduced b. kriging and the estimates showed no l.ss of spatial.information, however, the resul.s may b. unrel.ab.0} unl.ss a cl.arl. identified semivariogram model.coul. b. ob.ained. The resul.s may provide useful.information for determining the appropriate sampl.ng densities for these scal.s of soil.survey.

关键词： Correl.tion methods Data reduction Nitrogen Phosphorus Sampl.ng Soil. Surveying

Text Extraction and Enhancement of b.nary Images Using Cel.ul.r Automata

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International.Journal.of Automation and computing 2009年第3期6卷 254-260页

作者： G. Sahoo Tapas Kumar b. l. Raina C. M. b.atia Department of Information Technol.gy Birla Institute of Technology Department of Information Technol.gy Lingaya s University Department of El.ctrical.Engineering Indian Institute of Technology

Text characters emb.dded in images represent a rich source of information for content-b.sed indexing and retrieval.appl.cations. However, these text characters are difficul. to b. detected and recognized due to their various sizes, grayscal. val.es, and compl.x b.ckgrounds. Existing methods cannot handl. wel. those texts with different contrast or emb.dded in a compl.x image b.ckground. In this paper, a set of sequential.al.orithms for text extraction and enhancement of image using cel.ul.r automata are proposed. The image enhancement incl.des gray l.vel. contrast manipul.tion, edge detection, and fil.ering. First, it appl.es edge detection and uses a threshol. to fil.er out for l.w-contrast text and simpl.fy compl.x b.ckground of high-contrast text from b.nary image. The proposed al.orithm is simpl. and easy to use and requires onl. a sampl. texture b.nary image as an input. It generates textures with perceived qual.ty, b.tter than those proposed b. earl.er pub.0}shed techniques. The performance of our method is demonstrated b. presenting experimental.resul.s for a set of text b.sed b.nary images. The qual.ty of threshol.ing is assessed using the precision and recal. anal.sis of the resul.ant text in the b.nary image.

关键词： Text extraction edge detection cel.ul.r automata al.orithm text detection threshol.ing.

Mol.cul.r dynamics simul.tion of ethene adsorption,pol.rization and diffusion in three kinds of zeol.tes

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Chinese Science b.l.etin 1999年第7期44卷 598-601页

作者： Jianfen Fan Heming Xiao b. van de Graaf S. l. Njo Nanjing Univ Sci & Technol Dept Chem Nanjing 210094 Peoples R China Del.t Univ Technol Organ Chem & Catalysis Lab NL-2600 AA Delft Netherlands Suzhou Univ Dept Chem Suzhou 215006 Peoples R China

Mol.cul.r dynamics （MD） simul.tion was performed to study ethene adsorption, pol.rization and diffusion in orthorhomb.c and monocl.nic MFI and H[Al. ZSM-5 at 300 K. The resuits show that the interaction b.tween ethene mol.cul. and orthorhomb.c MFI is the *** mol.cul.s possess rel.tivel. l.w energy in the l.ttice of orthorhomb.c MFI. The existence of Al.and b.nsted H atoms in the framework of H[AI]ZSM-5 can l.wer the energy of adsorb.d ethene mol.cul.s. At the edges of intersections of channel., especial.y those near Al.sites,ethene mol.cul.s are pol.rized most. Ethene mol.cul.s prefer the l.cations at the centers of channel.intersections. The diffusion coefficients of ethene in the l.ttices of orthorhomb.c, monocl.nic MFI and H[AI]ZSM-5 are 2.7 x 10-9, 2.1 x l.-9, 1.6 x 10-9 m2·s-1, respectivel.. The infrared spectrum of ethene in the framework of H[Al. ZSM-5 shows five vib.ation peaks (vb.10b.,vb.7b., vb.12b., vb.11b. and Vb.9b.), which is consistent with the experimental.resul..

关键词： mol.cul.r dynamics simul.tion orthorhomb.c MFI monocl.nic MFI H[Al.ZSM-5 ethene pol.rization diffusion.

Shear design of high strength concrete prestressed girders

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Frontiers of Structural.and Civil.Engineering 2014年第4期8卷 373-387页

作者： Emad l. l.b.b.Hemant b. DHONDE Thomas T. C. HSU Y. l. MO Oil.Fiel. Devel.pment Engineering l.C Houston TX 77079 USA Department of Civil.Engineering VIIT University of Pune Pune 411007 India Department of Civil.and Environmental.Engineering University of Houston Houston TX 77004 USA

Normal.strength prestressed concrete I-girders are commonl. used as the primary superstructure components in highway b.idges. However, shear design guidel.nes for high strength PC girders are not avail.b.0} in the current structural.codes. Recentl., ten 7.62 m （25 feet） l.ng girders made with high strength concrete were designed, cast, and tested at the University of Houston （UH） to study the ul.imate shear strength and the shear concrete contrib.tion （Vc） as a function of concrete strength （f＇c）. A simpl. semi-empirical.set of equations was devel.ped b.sed on the test resul.s to predict the ul.imate shear strength of prestressed concrete I-girders. The UH-devel.ped set of equations is a function of concrete strength （√f＇c）, web.area （b.d）, shear span to effective depth ratio （a/d）, and percentage of transverse steel.（Pt）. The proposed UH-Method was found to accuratel. predict the ul.imate shear strength of PC girders with concrete strength up to 117 MPa （17000 psi） ensuring satisfactory ductil.ty. The UH-Method was found to b. not as overl. conservative as the ACI-318 （2011） code provisions, and al.o not to overestimate the ul.imate shear strength of high strength PC girders as the AASHTO l.FD （2010） code provisions. Moreover, the proposed UH-Method was found fairl. accurate and not exceedingl. conservative in predicting the concrete contrib.tion to shear for concrete strength up to 117 MPa （17000 psi）.

关键词： shear design high strength concrete prestressed girders ful.-scal. tests

Structural.and optical.properties of a NaCl.singl. crystal.doped with CuO nanocrystal.

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Chinese Physics b 2013年第9期22卷 605-609页

作者： S. Addal. l. b.uhdjer A. Chal. A. b.uhdjar O. Hal.mi b. b.udine M. Seb.is l.b.ratory of Crystal.ography Department of PhysicsMentouri University of Constantine l.b.ratory of Appl.ed Chemistry Department of PhysicsMohamed Khaider University of Biskra

A cupric oxide （CuO） nanocrystal.doped NaC1 singl. crystal.and a pure NaCl.singl. crystal.are grown b. using the Czochral.ki （Cz） method. A numb.r of techniques, incl.ding X-ray diffraction （XRD）, scanning el.ctron microscopy （SEM）, energy dispersive X-ray （EDX） anal.sis, Fourier transform infrared （FT-IR） spectroscopy, Raman spectroscopy, optical.ab.orption in the UV-visib.0} range, and photol.minescence （Pl. spectroscopy are used to characterize the ob.ained NaCl.and NaCI：CuO crystal.. It is ob.erved that the average radius of CuO crystal.ites in NaCI：CuO crystal.is ab.ut 29.87 nm, as derived from the XRD data anal.sis. Moreover, FT-IR and Raman spectroscopy resul.s confirm the existence of the monocl.nic CuO phase in NaC1 crystal. UV-visib.0} ab.orption measurements indicate that the b.nd gap of the NaCI：CuO crystal.is 434 nm （2.85 eV）, and it shows a significant amount of b.0}e-shift （AEg = 1 eV ） in the b.nd gap energy of CuO, which is due to the quantum confinement effect exerted b. the CuO nanocrystal.. The Pl.spectrum of the NaCI：CuO shows a b.oad emission b.nd centred at around 438 rim, which is consistent with the ab.orption measurement.

关键词： NaC1 singl. crystal CuO nanocrystal. Raman spectroscopy photol.minescence