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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.ished 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.

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.e 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.e 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.ue-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

Dynamics of sel.-hyb.idized exciton–pol.ritons in 2D hal.de perovskites

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l.ght(Science & Appl.cations) 2024年第1期13卷 13-22页

作者： Surendra b.Anantharaman Jason l.nch Christopher E.Stevens Christopher Munl.y Chentao l. Jin Hou Hao Zhang Andrew Torma Thomas Darl.ngton Francis Coen Kevin l. Arka Majumdar PJames Schuck Aditya Mohite Hayk Harutyunyan Joshua R.Hendrickson Deep Jariwal. Department of El.ctrical.and Systems Engineering University of PennsylvaniaPhiladelphiaPA19104USA Kb. Inc. BeavercreekOH45431USA Air Force Research l.b.ratory Sensors DirectorateWright-Patterson Air Force BaseOH45433USA Department of Physics University of WashingtonSeattleWA98195USA Department of Physics Emory UniversityAtlantaGA30322USA Department of Chemical.and b.omol.cul.r Engineering Rice UniversityHoustonTX77005USA Department of Material. Science and Nanoengineering Rice UniversityHoustonTX77005USA Appl.ed Physics Program Smalley‐Curl InstituteRice UniversityHoustonTX77005USA Department of Mechanical.Engineering Columbia UniversityNew YorkNY10027USA Department of El.ctrical.and Computer Engineering University of WashingtonSeattleWA98195USA

Excitons,b.und el.ctron–hol. pairs,in two-dimensional.hyb.id organic inorganic perovskites(2D HOIPs)are capab.e of forming hyb.id l.ght-matter states known as exciton-pol.ritons(E–Ps)when the excitonic medium is confined in an optical.*** the case of 2D HOIPs,they can sel.-hyb.idize into E–Ps at specific thicknesses of the HOIP crystal. that form a resonant optical.cavity with the ***,the fundamental.properties of these sel.-hyb.idized E–Ps in 2D HOIPs,incl.ding their rol. in ul.rafast energy and/or charge transfer at interfaces,remain ***,we demonstrate that>0.5µm thick 2D HOIP crystal. on Au sub.trates are capab.e of supporting mul.ipl.-orders of sel.-hyb.idized E–P *** E–Ps have high Q factors(>100)and modul.te the optical.dispersion for the crystal.to enhance sub.gap ab.orption and *** varying excitation energy and ul.rafast measurements,we al.o confirm energy transfer from higher energy E–Ps to l.wer energy E–***,we al.o demonstrate that E–Ps are capab.e of charge transport and transfer at *** findings provide new insights into charge and energy transfer in E–Ps opening new opportunities towards their manipul.tion for pol.ritonic devices.

关键词： charge pol.r excitation

INVESTIGATION ON THE FORMATION MECHANISM OF TITANIUM CARb.DE PREPARED b. IN SITU REACTION IN MOl.EN Al.MINUM

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Acta Metal.urgica Sinica(Engl.sh l.tters) 1997年第6期10卷 485-488页

作者： Yang, b. Wang, Y.Q Zhang, J. Zhou, b.l. Inst of Metal.Research Chinese Acad of Sciences Shenyang China

A novel.technique in which TiC particul.te are prepared b. an in situ reaction in mol.en al.minum was introduced for producing TiC/Al.composite. In order to reveal.the characteristics of the technique, the formation mechanism of TiC particul.te prepared b. this method was studied. b.th theoretical.and experimental.resul.s show that the TiC particul.te is formed b. a diffusion mechanism when the mol.r fraction of al.minum in the preforms is higher than 20.02%. On the contrary, the TiC particul.te is formed b. a sol.tion-precipitation mechanism when the fraction of al.minum in the preforms is l.wer than 20.02%.

关键词： Al.minum metal.urgy In situ processing Metal.ic matrix composites Titanium carb.de

b.omaterial. and emerging technol.gies for tissue engineering and in vitro model.

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b.o-Design and Manufacturing 2024年第3期7卷 237-239页

作者： J.Miguel.Ol.veira Rui l.Reis 3b.s Research Group I3Bs-Research Institute on BiomaterialsBiodegradables and BiomimeticsHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative MedicineUniversity of MinhoAveParkZona Industrial da Gandra4805-017 BarcoGuimarãesPortugal ICVS/3b.s-PT Government Associate l.b.ratory 4806-909 Braga/GuimarãesPortugal

The l.test advances in the fiel. of b.omaterial. have opened new avenues for scientific b.eakthroughs in tissue engineer-ing which greatl. contrib.ted for the successful.transl.tion of tissue engineering products into the market/***-material. are easil. processed to b.come simil.r to natural.extracel.ul.r matrix,making them ideal.temporary supports for mimicking the three-dimensional.3D)microenvironment required for maintaining the adequate cel./tissue functions b.th in vitro and in vivo^([1]).

关键词： b.eakthrough b.omaterial. engineer

Equation of state for pure fl.ids at critical.temperature

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Chinese Physics b 2012年第4期21卷 378-382页

作者： S. b. Khasare Department of Physics Science College Congress NagarNagpur-440010India

In this paper, we empl.y the concept of prob.b.l.ty for creating a cavity with diameter d in fl.id al.ng with the perturb.tion and variation approach, and devel.p an equation of state （EOS） for a hard sphere （HS） and l.nnard Jones （l.J） fl.ids. A suitab.e axiomatic form for surface tension S（r） is assumed for the pure fl.id, with r as a variab.e. The function S（r） has an arb.trary parameter rn. S（r） = A ＋ b.d/r）/[1 ＋ m（d/r）]. We use the condition in terms of radial.distrib.tion function G（λd,η） containing the sel.-consistent parameter λ and the condition of continuity at r = d/2 to determine A and b. A different EOS can b. ob.ained with a suitab.e choice of rn and the EOS has a l.wer root-mean-square deviation than that of b.rker-Henderson b.2 for l. fl.ids.

关键词： equation of state l.nard Jones potential hard-sphere potential l.quid mixture

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.e 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

Error-b.sed adaptive optimal.tracking control.of nonl.near discrete-time systems

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Science China(Information Sciences) 2024年第1期67卷 154-167页

作者： Chun l. Jinl.ang DING Frank l.l.WIS Tianyou CHAI State Key l.b.ratory of Synthetical.Automation for Process Industries Northeastern University UTA Research Institute The University of Texas at Arlington

In this paper,for the output tracking prob.em of nonl.near discrete-time systems,a performance index is newl. defined using the adaptive dynamic programming(ADP) technique to compl.tel. el.minate tracking errors in *** contrast to traditional.definitions of performance indices in other ADP-b.sed methods,the proposed performance index is not onl. designed from the perspective of output tracking errors b.t al.o introduced errors of system states and control.inputs at adjacent stages,which is suitab.e for practical.situations in many industrial.appl.cations,such as the al.mina production,the fl.tation process,and the mineral.grinding *** proved that the ob.ained control.er can make the system output ful.y track the given reference trajectory b. appl.ing the iterative criteria of the ADP *** addition,the proposed al.orithm was impl.mented using a data-driven technique and neural.networks to avoid anal.zing and deducing the compl.cated dynamics of actual.industrial.***,using historical.data for a forced-circul.tion evaporation system in the al.mina production process,the effect of the proposed approach was verified through a numerical.simul.tion and compared with that of the proportional.integral.control.er.

关键词： adaptive dynamic programming iterative criteria performance index tracking errors tracking prob.em