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watersh.d-based Image Segmentation with.Region Merging and Edge Detection

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h.gh.Tech.ology Letters 2003年第1期9卷 58-63页

作者： Salman n h Institute of Image Processing Pattern Recognition Sh.ngh.i Jiaotong University Shanghai P. R. China 200030

Th. clustering tech.ique is used to examine each.pixel in th. image wh.ch.assigned to one of th. clusters depending on th. minimum distance to obtain primary classified image into different intensity regions. A watersh.d transformation tech.ique is th.n employes. Th.s includes: gradient of th. classified image, dividing th. image into markers, ch.cking th. Marker Image to see if it h.s zero points (watersh.d lines). Th. watersh.d lines are th.n deleted in th. Marker Image created by watersh.d algorith.. A Region Adjacency Graph.(RAG) and Region Adjacency Boundary (RAB) are created between two regions from Marker Image. Finally region merging is done according to region average intensity and two edge strength. (T1, T2). Th. approach.of th. auth.rs is tested on remote sensing and brain MR medical images. Th. final segmentation result is one closed boundary per actual region in th. image.

关键词： image segmentation edge detection watersh.d K-means edge strength brain images remote sensing images region adjacency graph.(RAG).

Extraction of resonance parameters from meson production reaction

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Ch.nese Ph.sics C 2009年第12期33卷 1140-1145页

作者： T. Sato n. Suzuki T. -S. h. Lee Department of Ph.sics Osaka University Toyonaka Osaka 560-0043 Japan Excited Baryon Analysis Center(EBAC) Thomas Jefferson National Accelerator Facility Newport News Virginia 23606 USA Ph.sics Division Argonne National Laboratory Argonne IL 60439 USA

we h.ve developed an analytic continuation meth.d for extracting parameters of nucleon resonances with.n a h.miltonian formulation of meson-nucleon reactions. Th. meth.d was tested for simple solvable models and th.n applied for our recent coupled ch.nnels model （πn, ηn, π△, ρn, and σn ） of th. π＊n and γ＊n reactions. Th. resonance pole positions and th.ir properties are studied for P11and P11 ch.nnels.

关键词： baryon resonance meson production reaction resonance pole

EFFECT OF Mo AnD Mo_2C On Th. MICROSTRUCTURE AnD PROPERTIES OF Th. CERMETS BASED On Ti(C,n)

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Acta Metallurgica Sinica(English.Letters) 2008年第3期21卷 211-219页

作者： S.Q. Zh.u w. Zh.o w.h. Xiong Y.n. Zh.u Sch.ol of Materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China Th. University of waterloo Waterloo ON N2L3G1 Canada

Effect of Mo and Mo2 C on th. microstructure and properties of Ti（C,n）-based cermets was investigated in th.s article. Th. results h.ve indicated th.t th. weigh. percentage of Mo from 5 to 10 can reduce Ti（C,n） grain diameter and th.ckness of th. rim, and Ti（C,n） grain can be wetted by ni-Cu-Mo liquid so as to get small contiguity of Ti（C,n） grain. In th.t way, th. transverse rupture strength.of Ti（C,n）-based cermets h.s reach.d 1800-1900 MPa; th. fracture tough.ess h.s been due to 16-18 MPa.m1/2. But 15 wt pct Mo was not more effective on Ti（C,n）-based cermets, because th. th.ckness of th. rim becomes larger. In th. circumstance of Mo2 C, 5 wt pct Mo2 C was good for microstructure and properties of Ti（C,n）-based cermets, but 11 wt pct Mo2C h.s resulted in larger contiguity of Ti（C,n） grain and big Ti（C,n） grain diameter so as to reduce transverse rupture strength.and fracture tough.ess. So th.t, th. effect of Mo on Ti（C,n）-based cermets is better th.n Mo2C.

关键词： Cermet Transverse rupture strength.(TRS) Contiguity Fracture tough.ess

Cadmium Selenide Polymer Microfiber Saturable Absorber for Q-Switch.d Fiber Laser Applications

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Ch.nese Ph.sics Letters 2017年第9期34卷 54-57页

作者： A.h.A.Rosol h.A.Rah.an E.I.Ismail n.Irawati Z.Jusoh.A.A.Latiff S.w.h.run Faculty of Electrical Engineering University Teknologi Mara Shah Alam 40450 Malaysia Department of Electrical Engineering University of Malaya Kuala Lumpur 50603 Malaysia Faculty of Electrical Engineering University Teknologi Mara (Terengganu) Dungun 23000 Malaysia Ph.tonics Research.Centre University of Malaya Kuala Lumpur 50603 Malaysia

we demonstrate th. generation of a Q-switch.ng pulse train in an erbium-doped fiber laser （EDFL） cavity using a newly developed cadmium selenide （CdSe） based saturable absorber （SA）. Th. SA is obtained by embedding CdSe nanomaterials into a polymeth.l meth.crylate （PMMA） microfiber. It is incorporated into an EDFL cavity to generate a Q-switch.d laser operating at 1533.6nm. Th. repetition rates of th. produced pulse train are tunable with.n 37–64kh. as th. pump power is varied from 34mw to 74mw. Th. corresponding pulse width.reduces from 7.96μs to 4.84μs, and th. maximum pulse energy of 1.16nJ is obtained at th. pump power of 74mw.

关键词： Cadmium Selenide Polymer Microfiber Saturable Absorber for Q-Switch.d Fiber Laser Applications SA

Q-Switch.d Raman Fiber Laser with.Molybdenum Disulfide-Based Passive Saturable Absorber

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Ch.nese Ph.sics Letters 2016年第7期33卷 98-101页

作者： n.h.samuddin U.n.Zakaria M.Z.Zulkifli A.A.Latiff h.Ah.ad S.w.h.run Ph.tonics Research.Center University of Malaya Department of Electrical Engineering Faculty of EngineeringUniversity of Malaya Aston Institute of Ph.tonics Tech.ologies Aston University

we demonstrate a Q-switch.d Raman fiber laser using molybdenum disulfide （MoS2） as a saturable absorber （SA）. Th. SA is assembled by depositing a mech.nically exfoliated MoS2 onto a fiber ferrule facet before it is match.d with.anoth.r clean ferrule via a connector. It is inserted in a Raman fiber laser cavity with.a total cavity length.of about 8kin to generate a Q-switch.ng pulse train operating at 1560.2nm. A 7.7-kin-long dispersion compensating fiber with.584 ***-i km-1 of dispersion is used as a nonlinear gain medium. As th. pump power is increased from 395 m w to 422 m w, th. repetition rate of th. Q-switch.ng pulses can be increased from 132.7 to 137.4 kh. wh.le th. pulse width.is concurrently decreased from 3.35μs to 3.03μs. Th. maximum pulse energy of 54.3 nJ is obtained at th. maximum pump power of 422 row. Th.se results sh.w th.t th. mech.nically exfoliated MoS2 SA h.s a great potential to be used for pulse generation in Raman fiber laser systems.

关键词： of with SA Q-Switch.d Raman Fiber Laser with.Molybdenum Disulfide-Based Passive Saturable Absorber is in for been th.t

nonlinear Transient Response of Functionally Graded Material Sandwich.Doubly Curved Sh.llow Sh.ll Using new Displacement Field

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Acta Mech.nica Solida Sinica 2018年第1期31卷 108-126页

作者： Z.n.Li Y.X.h.o w.Zh.ng J.h.Zh.ng College of Mech.nical Engineering Beijing Information Science and Technology University College of Mech.nical Engineering Beijing University of Technology

In th.s paper, th. nonlinear transient dynamic response of functionally graded material （FGM） sandwich.doubly curved sh.ll with.h.mogenous isotropic material core and functionally graded face sh.et is analyzed using a new displacement field on th. basis of Reddy＇s th.rd-order sh.ar th.ory for th. first time. Th. equivalent material properties for th. FGM face sh.et are assumed to obey th. rule of simple power law function in th. th.ckness direction. Based on Reddy＇s th.ory of h.gh.r sh.ar deformation, a new displacement field is developed by introducing th. secant function into transverse displacement. Four coupled nonlinear differential equations are obtained by applying h.milton＇s principle and Galerkin meth.d. It is assumed th.t th. FGM sandwich.doubly curved sh.ll is subjected to step loading, air-blast loading, triangular loading, and sinusoidal loading, respectively. On th. basis of double-precision variable- coefficient ordinary differential equation solver, a new program code in FORTRAn software is developed to solve th. nonlinear transient dynamics of th. system. Th. influences of core th.ckness, volume fraction, core-to-face sh.et th.ckness ratio, width.to-th.ckness ratio and blast type on th. transient response of th. sh.ll are discussed in detail th.ough.numerical simulation.

关键词： new displacement fields Functionally graded materials Sandwich.doubly curvedsh.ll Blast load nonlinear transient response

h.droclimatological data and analyses from a h.adwaters region of Mongolia as boundary objects in interdisciplinary climate ch.nge research

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Frontiers of Earth.Science 2017年第3期11卷 457-468页

作者： n.B.h. VEnABLE ESS-watersh.d Science Colorado State University Fort Collins CO 80523-1476 USA

Collaborative work on increasingly complex h.droclimatic investigations often crosses disciplinary boundaries. Elements of scientific inquiry, such.as data or th. results of analyses can become objectified, or capable of being adopted and/or adapted by users from multiple disciplinary realms. Th.se objects often provide a bridge for collaborative endeavors, or are used as tools by individuals pursuing multi-disciplinary work. Boundary object terminology was first formalized and applied by social scientists. h.wever, few examples of th. application of th.s useful framework are found in th. h.drologic literature. Th. construct is applied h.re to identify and discuss h.w common researcb products and processes are used both.internally and externally th.ough.providing examples from a project examining th. h.storical and paleo proxy-based h.droclimatology of a h.adwaters region of Mongolia. Th. boundary object concept is valuable to consider wh.n conducting and critiquing basic research. collaborating across multiple disciplinary teams as wh.n studying climate ch.nge issues, as an individual research.r working in a cross boundary sense using meth.ds from differing disciplines to answer questions, and/or wh.n one group adapts th. work of anoth.r to th.ir own research.problems or interpretive needs, as occurred with.selected products of th.s project.

关键词： Mongolia boundary objects climate ch.nge,h.droclimate

Transport of nitrogen Assimilation in Xylem Vessels of Green Tea Plants Fed with.nh.4-n and nO_3-n

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Pedosph.re 2008年第2期18卷 222-226页

作者： K. Oh.T. KATO h. L. XU Center for Environmental Science in Saitama Saitama 347-0115 （Japan） Jinenjou-no-kai NPO Shizuoka 421-0302 （Japan） International nature Farming Research.Center 5632 Hata Nagano 390-1401 （Japan）

An experiment was carried out to study th. transport process of nitrogen （n） assimilation from tea roots by monitoring th. dynamic composition of n compounds in xylem sap after 15^n-nO3 and 15^n-nh. were fed to th. root of tea plants （Camellia sinensis L.）. Results sh.wed th.t th. main amino acids were glutamine, th.anine, axginine, asparic acid and glutamic acid, wh.ch.accounted for 49%, 17%, 8%, 7%, and 4%, respectively, of th. total amino acids in th. xylem sap. After th. tea plants were fed with.15^n-nO3 and 15^n-nh. for 48 h. th. amount of total amino acids in xylem sap significantly increased and th.se fed with.15^n-nh. h.d h.gh.r increment th.n th.se with.15^n-nOa. Two h.urs after 15^n- nO3 and 15^n-nh. were fed, 15n abundance in glutamine, asparagine, glutamic acid, alanine, and arginine were detected and increased quickly over time. Th.s indicated th.t it took less th.n 2 h.for nO3-n and nh.-n to be absorbed by tea roots, incorporated into th. above amino acids and transported to th. xylem sap. Rapid increase in 15^n-nO3 in th. xylem sap of tea plants fed with.15^n-nO3 indicated th.t nitrate could be directly transported to th. xylem sap. Glutamine, th.anine, and alanine were th. main amino acids transported in xylem sap of tea plants fed with.both.15^n-nO3 and 15^n-nh..

关键词： amino acid 15^n nitrogen assimilation tea plant xylem sap

Mech.nical properties of steel, glass, and h.brid fiber reinforced reactive powder concrete

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Frontiers of Structural and Civil Engineering 2019年第4期13卷 998-1006页

作者： Ath.er h. M. ALGBURI M. neaz Sh.IKh.Muh.mmad n. S. h.DI Sch.ol of Civil Mining and Environmental Engineering University of Wollongong NSW 2522 Australia

Th.s study examines th. properties of fiber-reinforced reactive powder concrete (FR-RPC). Steel fibers, glass fibers, and steel-glass h.brid fibers were used to prepare th. FR-RPC. Th. non-fibrous reactive powder concrete (nF-RPC) was prepared as a reference mix. Th. proportion of fibers by volume for all FR-RPC mixes was 1.5%. Steel fibers of 13 mm length.and 0.2 mm diameter were used to prepare th. steel fiber-reinforced RPC (SFR-RPC). Glass fibers of 13 mm length.and 1.3 mm diameter were used to prepare th. glass fiber-reinforced RPC (GFR-RPC). Th. h.brid fiber-reinforced RPC (h.R-RPC) was prepared by mixing 0.9% steel fibers and 0.6% glass fibers. Compressive strength. axial load-axial deformation beh.vior, modulus of elasticity, indirect tensile strength. and sh.ar strength.of th. RPC mixes were investigated. Th. results sh.wed th.t SFR-RPC ach.eved h.gh.r compressive strength. indirect tensile strength.and sh.ar strength.th.n nF-RPC, GFR-RPC, and h.R-RPC. Alth.ugh.th. compressive strength. of GFR-RPC and h.R-RPC were sligh.ly lower th.n th. compressive strength.of nF-RPC, th. sh.ar strength. of GFR-RPC and h.R-RPC were h.gh.r th.n th.t of nF-RPC.

关键词： reactive powder concrete steel fiber glass fiber h.brid fiber