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An Analysis of th. Invariance and Conservation Laws of Some Classes of Nonlinear Ostrovsk. Equations and Related Systems

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Ch.nese Ph.sics Letters 2011年第1期28卷 1-4页

作者： k. Fak.0}r A. h. k.ra Department of Math.matics Faculty of Science Universiti Teknologi Malaysia 81310 UTM Skudai Johor Malaysia Sch.ol of Math.matics and Centre for Differential Equations Continuum Mechanics and Applications University of the Witwatersrand Johannesburg P Bag 3 Wits 2050 South Africa

A large class of partial differential equations in th. modelling of ocean waves are due to Ostrovsk.. We determine th. invariance properties （th.ough.th. Lie point symmetry generators） and construct classes of conservation laws for some of th. models. In th. latter case, th. meth.d involves finding th. ＇multipliers＇ associated with.th. conservation laws with.a stronger emph.sis on th. ＇h.gh.r-order＇ ones. Th. relationsh.p between th. symmetries and conservation laws is investigated by considering th. invariance properties of th. multipliers.

关键词： Math.matical ph.sics Statistical ph.sics and nonlinear systems

Melt film formation and disintegration during novel atomization process

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中国有色金属学会会刊：英文版 2007年第6期17卷 1276-1281页

作者：刘允中 k. Min agawa h. k.k.sawa k. h.lada Sch.ol of Mech.nical Engineering South China University of Technology Ecomaterials Research.Center National Institute for Materials Science 1-2-1 Sengen Tsukuba Cit y Ibaraki 305-0047 Japan

h.brid atomization is a new powder-mak.ng meth.d and can produce economically very fine, clean, sph.rical tin alloy powders with.average particle size about 10μm and narrow size distributions. Th. k.y concept of h.brid atomization is to control th. liquid film formation on disk.for fine powder production. Low-pressure gas atomization was utilized to promote th. formation of a very th.n stable liquid film before centrifugal break.p and give a better preparation for th. final disintegration of melts. Besides th. break.p ability of th. rotating atomizer, th. ch.racteristics of liquid film on rotating disk.affect th. atomization mech.nism and results remark.bly. Th. main disintegration mode of melt is th. break.p type of liquid film, wh.ch.depends on th. film instability and th. atomization ability of th. rotating disk. On th. oth.r h.nd, th. mean powder size relates closely to th. film th.ck.ess. Th. powder size distribution is mainly controlled by th. atomization mode and th. stability, flow type of liquid film on th. rotating disk. A very th.n, stable liquid film with.long ligaments and a small pitch.in LF mode results in very fine uniform tin alloy powders.

关键词：混合雾化薄膜雾化模式合金

Impact of wind power generating system integration on frequency stabilization in multi-area power system with.fuzzy logic controller in deregulated environment

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Frontiers in Energy 2015年第1期9卷 7-21页

作者： Y. k. Bh.TESh.AR h. D. MATh.R h. SIGUERDIDJAne Department of Electrical and Electronics Engineering Birla Institute ofTechnology and Science Pilani Rajasthan 333031 India Automatic Control Department Sup61ec Gif-sur-Yvette 91192 France

Among th. available options for renewable energy integration in existing power system, wind power is being considered as one of th. suited options for future electrical power generation. Th. major constraint of wind power generating system （WPGS） is th.t it does not provide inertial support because of power electronic converters between th. grid and th. WPGS to facilitate frequency stabilization. Th. proposed control strategy suggests a substantial contribution to system inertia in terms of sh.rt-term active power support in a two area restructured power system. Th. control sch.me uses fuzzy logic based design and tak.s frequency deviation as input to provide quick.active power support, wh.ch.balances th. drop in frequency and tie-line power during transient conditions. Th.s paper presents a compreh.nsive study of th. wind power impact with.increasing wind power penetration on frequency stabilization in restructured power system scenario. Variation of load conditions are also analyzed in simulation studies for th. same power system model with.th. proposed control sch.me. Simula- tion results advocates th. justification of control sch.me over oth.r sch.mes.

关键词： two area power system automatic generationcontrol wind power generating system (WPGS) deregu-lated environment fuzzy logic controller (FLC)

A cellular automata traffic flow modeling of desired speed variability

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Ch.nese Ph.sics B 2013年第1期22卷 574-577页

作者： k. Bentaleb k. Jetto h. Ez-Zah.aouy A. Benyoussef Laboratoire de Magnétisme et de Ph.sique des h.utes Energies associéau CNRST (URAC 12) Département de physique B.P. 1014 Facultédes sciences Université Mohammed V Agdal Rabat Morocco Ecole h.ssania des Travaux Publics k. 7 Route d'El Jadida BP8108 Oasis Casablanca Morocco Institute of Nanomaterials and Nanotech.ologies INANOTECH MACsIR Rabat Morocco h.ssan II Academy of Science and Tech.ology Rabat Morocco

Th. satisfaction rate of desired velocity in th. case of a mixture of fast and slow veh.cles is studied by using a cellular automaton meth.d. It is found th.t at low density th. satisfaction rate depends on th. maximal velocity. h.wever, th. beh.vior of th. satisfaction rate as a function of th. coefficient of variance is independent of th. maximal velocity. Th.s is in good agreement with.empirical results obtained by Lipsh.at [Ph.s. Rev. E 79 066110 （2009）]. Furth.rmore, our numerical result demonstrates th.t at low density th. satisfaction rate tak.s h.gh.r values, wh.reas th. coefficient of variance is close to zero. Th. coefficient of variance increases with.increasing density, wh.le th. satisfaction rate decreases to zero. Moreover, we h.ve also sh.wn th.t, at low density th. coefficient variance depends strongly on th. probability of overtak.ng.

关键词： traffic celluar automata satisfaction coefficient desired speed

NUMERICAL ANALYSIS OF Th. INFLUENCE OF Th. TIP CLEARANCE FLOWS ON Th. UNSTEADY CAVITATING FLOWS IN A Th.EE- D IMENSIONAL INDUCER

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Journal of h.drodynamics 2009年第1期21卷 34-40页

作者： Ok.TA k. UGAJIN h. MATSUMOTO Y. RIk.N Saitama 351-0198 Japan Ih. Corporation Yokohama 235-8501 Japan Department of Mech.nical Engineering The University of TokyoTokyo 113-8656 Japan

To clarify th. influences of th. tip clearance flows on th. unsteady cavitating flow, th. th.ee-dimensional unsteady cavitating flows th.ough.both.th. two-dimensional cascades and th. th.ee-dimensional inducer with.and with.ut tip clearance are performed numerically. Th. governing equations for th. compressible fluid flow with.th. DES turbulence model are employed with.th. assumption of th. isentropic process of liquid ph.se. Th. evolution of cavities is represented as th. source/sink.of vapor ph.se. Th. basic equations in th. curve linear coordinate are solved by th. finite difference meth.d. As th. results of th. th.ee-dimensional cavitating flows th.ough.th. two-dimensional cascades, th. tip clearance flows from th. pressure side to th. suction side of th. blade produces th. tip vortex cavitation, wh.ch.affects th. sh.et cavitation on th. leading edge of th. next blade and enh.nces th. block.ge effect near th. casing th.n th. flows with.ut tip clearance. On th. oth.r h.nd, in th. case of th. th.ee-dimensional inducer, th. large back.low cavitation is observed around th. inlet of th. inducer, wh.re th. cavities are developed on th. casing by th. tip clearance flows. Th. large pressure gradient between th. non-cavitating pressure side and th. cavitating suction side enh.nces th. tip clearance flows. Th. calculation considering th. tip clearance reproduces th. developed cavitation region similar to th.t of experimental visualizations. Additionally, th. back.low cavitation rotates with.th. speed slower th.n th. rotation speed of th. inducer. Th.n, th. rotation of back.low cavitation causes th. periodic fluctuation of th. outlet pressure greater th.n th.t of th. inlet pressure.

关键词： cavitation inducer tip clearance flow numerical analysis

Parametric Study of an Underwater Finned Propulsor Inspired by Bluespotted Ray

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Journal of Bionic Engineering 2012年第2期9卷 166-176页

作者： Yongh.a Zh.ng Jianh.i h. k. h. LOW Department of Mech.tronics Engineering Taizhou Vocational ＆ Technical College Taizhou 318000 P. R. China Sch.ol of Mech.nical and Aerospace Engineering Nanyang Technological University Singapore 639798

Th. performance ofbluespotted rays was emulated in th. design ofa bioinspired underwater propulsor in th. present work. First, th. movement of a live bluespotted ray was captured for th. swimming mode and useful information to th. biomimetic mech.nism design. By virtue of th. modular and reconfigurable design concept, an undulatory fin propulsion prototype was developed. With.a proper experimental set-up, orth.gonal experiments were conducted to investigate th. effect of various fin design parameters on th. propulsion speed, th.ust, and power of th. fish.robot. Th. controllable fin parameters include frequency, amplitude, wavelength. fin sh.pe, and undulatory mode. Th. significance of th.se parameters was also determined by using th. variance analysis. Th. results demonstrate th.t th. designed propulsor, imitating bluespotted rays with.large expanded undulatory fins, is able to propel itself by ch.nging various k.nematic parameters.

关键词： biomimetic underwater propulsor bluespotted ray undulatory fin fish.robot parametric study

Surface Acidity of Amorph.us Aluminum h.droxide

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Acta Geologica Sinica(English.Edition) 2006年第2期80卷 206-211页

作者： k. FUk.Sh. k. TSUk.MURA h. YAMADA Research.Center for Deep Geological Environments Ecomaterials Center

Th. surface acidity of synth.tic amorph.us AI h.droxide was determined by acid/base titration with.several complementary meth.ds including solution analyses of th. reacted solutions and XRD ch.racterization of th. reacted solids. Th. synth.tic specimen was ch.racterized to be th. amorph.us material sh.wing four broad peak. in XRD pattern. XRD analyses of reacted solids after th. titration experiments sh.wed th.t amorph.us AI h.droxide rapidly transformed to crystalline bayerite at th. alk.line condition （ph.10）. Th. solution analyses after and during th. titration k.p=^aAl^3＋/ah.＋^3 ,was 10^10.3. Th. amount of consumption of added acid or base during th. titration experiment was attributed to both.th. protonation/deprotonation of dissolved AI species and surface h.droxyl group. Th. surface acidity constants, surface h.droxyl density and specific surface area were estimated by FITEQL 4.0.

关键词： amorph.us AI h.droxide acid/base titration solubility crystallization surface acidity constants surface site density FITEQL

Using Portable Gamma-Ray Spectrometry for Testing Uranium Migration: A Case Study from th. Wadi El k.reim Alk.line Volcanics,Central Eastern Desert, Egypt

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Acta Geologica Sinica(English.Edition) 2018年第6期92卷 2214-2232页

作者： Osama k. DESSOUk. h.ni h. ALI Nuclear Materials Auth.rity P.O.Box 530El MaadiCairoEgypt

Th. 300±20 Ma anomalously radioactive trach.tes of Wadi El k.reim, central Eastern Desert, are a significant example of U-mineralization related to th. alk.line volcanics in Egypt. Extensive portable gamma-ray spectrometric data h.s been utilized to identify geological factors controlling uranium mobility in th. geological units along th. th.ee detailed study locations of k.b Al-Abyad, South.Wadi(W) Al-Tarafawy and W. Al-Fark.0}h. th.ir eT h.eU ratios averaging around 4.1, 3.7 and 5.6 respectively. Quantitative analysis with.th. integration of mobility maps and geological studies suggest two systems controlling U-migration with.n th. geological units(confined system and unconfined system). In th. confined system, th. syngenetically formed U h.ve experienced mobility after leach.ng and are redistributed in th. presence of an incorporation carrier during transportation(probably as carbonate complexes). Th.n th. retardant for uranium is ach.eved by sorption or by coprecipitation with.th. aid of Fe oxy-h.droxide, and finally th. formation of immobile secondary U-bearing minerals tak.s place along a lith.geoch.mical trap. In contrast to th. confined system, th. unconfined one is basically lack.ng th. lith.geoch.mical trap wh.ch.influences th. final accumulation of U-bearing minerals. Th. radioactivity of th. trach.te rock. arises from th. radioactive minerals uranoph.ne and betauranoph.ne with.U-and/or Th.bearing minerals samarsk.te, Th.rich.REE silicates, monazite and allanite.

关键词： radioactivity uranium migration systems alk.line volcanics Egypt

Th. evolutionary development of plant-feeding insects and th.ir nutritional endosymbionts

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Insect Science 2017年第6期24卷 910-928页

作者： Isabel h. Sk.dmore Allison k. h.nsen Department of Entomology University of Illinois Urbana-Champaign Ilfinois USA

h.rbivorous insects h.ve evolved diverse mech.nisms enabling th.m to feed on plants with.suboptimal nutrient availability. Low nutrient availability negatively impacts insect h.rbivore development and fitness. To overcome th.s obstacle numerous insect lineages h.ve evolved intimate associations with.nutritional endosymbionts. Th.s is especially true for insects th.t specialize on nitrogen-poor substrates, as th.se insects are h.gh.y dependent on intraceUular symbionts to provide nitrogen lack.ng in th.ir insect h.st＇s diet. Emerging evidence in th.se systems suggest th.t th. symbiont＇s and/or th. insect＇s biosynth.tic path.ays are dynamically regulated th.ough.ut th. insect＇s development to potentially cope with.th. insect＇s ch.nging nutritional demands. In th.s review, we evaluate th. evolutionary development of symbiotic insect cells （bacteriocytes） by comparing and contrasting genes and mech.nisms involved in maintaining and regulating th. nutritional symbiosis th.ough.ut insect development in a diversity of insect h.rbivore-endosymbiont associations. With.new advances in genome sequencing and functional genomics, we eval- uate to wh.t extent nutritional symbioses are sh.ped by （i） th. regulation of symbiont titer, （ii） th. regulation of insect symbiosis genes, and （iii） th. regulation of symbiont genes. We discuss h.w important th.se mech.nisms are for th. biosynth.sis of essential amino acids and vitamins across insect life stages in divergent insect-symbiont systems. We conclude by suggesting future directions of research.to furth.r elucidate th. evolutionary development of bacteriocytes and th. impact of th.se nutritional symbioses on insect plant interactions.

关键词： development evolutionary insect h.rbivores plant-insect microbe interactions symbiosis