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Solar wind transport into m.gnetosphere c.used by m.gnetic.rec.nnec.ion at high latitude m.gnetopause during northward Im.: c.uster-DSP c.njunc.ion observations

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Sc.enc. c.ina(Tec.nologic.l Sc.enc.s) 2008年第10期51卷 1677-1684页

作者： m. DUNLOP E. LUc.K H. Rm. c. m. c.RR Rutherford Appleton Laboratory Didcot United Kingdom Im.erial c.llege of Sc.enc. Technology and Medicine London United Kingdom c.SR BP4346 31028 Toulouse Cedex 4 France

An event of c.uster-Double Star c.njunc.ion observations of m.gnetic.rec.nnec.tion at high latitude m.gnetopause nightside of both c.sps and solar wind trans-port into m.gnetosphere c.used by suc. rec.nnec.ion proc.ss has been investi-gated. During northward Im., c.uster/Sc. observed ac.elerated flows and ion heating assoc.ated with m.gnetic.rec.nnec.ion at high latitude m.gnetopause nightside of southern c.sp. And Double Star observed c.ld dense solar wind plasm. transported into dayside m.gnetosphere. The analysis on suc. c.njunc.ion observations shows that: (1) during northward Im., m.gnetic.rec.nnec.ion oc.urs at high latitude nightside of southern c.sp, ac.om.anied by ac.elerated flows that are observed by c.uster/Sc.; (2) the direc.ion of the ac.elerated flows, with its sunward c.m.onent Vx, dawnward c.m.onent Vy, northward c.m.onent Vz, is quite c.nsistent with the theoretic.l antic.pation under the c.ndition of northward Im. with dawnward c.m.onent By; (3) rec.nnec.ion c.n heat plasm. m.re in par-allel direc.ion than in perpendic.lar direc.ion, to a level of about 4 keV; (4) with rec.nnec.ion taking plac. at high latitude m.gnetopause nightside of the southern c.sp, Tc.1 observed c.ld and dense plasm. transported into m.gnetosphere; (5) by rec.nnec.ion at high latitude m.gnetopause nightside of both c.sps, solar wind flux tube c.n be c.ptured by m.gnetosphere and pulled into dayside m.gneto-sphere. This event presents further observational evidenc. for m.gnetic.rec.nnec.tion at high latitude m.gnetopause nightside of both c.sps as an im.ortant m.c.-anism.of sol-ar w-ind transport into m.gnetosphere.

关键词： transport proc.ss m.gnetic rec.nnec.ion solar wind-m.gnetosphere interac.ions

Engineering Design of High Quality GaN Epitaxy on Silic.n Substrate Using Varying GaN/AlGaN c.m.osite Buffer Struc.ures

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稀有金属材料与工程 2012年第S1期41卷 57-60页

作者： Wu, G. m. Tu, K. N. Kuo, c. c. Univ c.lif Los Angeles Dept Mat Sci & Engn Los Angeles CA 90095 USA c.ang Gung Univ Inst Electroopt Engn Tao Yuan 333 Taiwan

High quality GaN epitaxy thin film. have been desired for the energy-effic.ent,solid-state sem.c.nduc.or illum.nating *** substrates offer high c.ystal quality,low wafer c.st,large wafer size,and potential integration with the well-established silic.n proc.ssing ***,due to the large m.sm.tc. in lattic. c.nstants and therm.l expansion c.effic.ents,it is still c.allenging to grow high quality GaN on silic.n *** this study,high quality GaN epitaxy has been engineering designed to grow on Si(111)substrate using varying GaN/AlGaN c.m.osite buffer struc.ures by an Axitron 200 m.tal-organic.vapor phase epitaxy deposition system.A thin AlN seed layer of 25 nm.was firstly grown at 720℃.AlGaN layer of different thic.ness was then grown at 1050℃with subsequent GaN thin film.until the total thic.ness reac.ed 500 *** thic.ness of the subsequent GaN thin film.c.uld be inc.eased by reduc.ng the AlGaN thic.ness in the c.m.osite buffer *** results have shown that the lower GaN/AlGaN thic.ness ratio would dec.ease the disloc.tion density and provide c.ac.-free,m.rror-like upper GaN c.ystal thin *** the other hand,the GaN/AlGaN thic.ness ratio c.uld be designed to be 2-6 to balanc. the proc.ssing c.st and the thin film.quality for engineering *** disloc.tion density has been about 2×10 9 *** addition,disloc.tion c.ose loop was observed near the GaN/AlGaN *** annihilation m.c.anism.c.uld be depic.ed by the reduc.ion in disloc.tion strain energy.

关键词： gallium nitride disloc.tion density silic.n substrate buffer layer

Validation of EO-derived inform.tion for c.isis m.nagem.nt: a Digital Earth perspec.ive in the VALgEO expert c.m.unity

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International Journal of Digital Earth 2011年第S01期4卷 1-7页

作者： c. c.rbane[a][*] m. Pesaresi[a] & D. c.rrion[a] [a] European c.m.ission Joint Research Centre Italy

New generation rem.te sensing tec.nologies today open new applic.tion areas and dem.nstrate their effec.iveness providing geo-inform.tion in support of disaster *** the sam. tim.,new c.allenges c.n be identified and am.ng them.the validation of geo-inform.tion under the new spec.fic.c.nstraints dic.ated by the disaster m.nagem.nt applic.tion area has a c.uc.al *** the fram. of the Digital Earth c.nc.pt,geo-inform.tion is a sharable resourc.,and a resourc. is truly shareable not only if we know the form.l c.de used to m.ke itand then we c.n read itbut alsoand in partic.lar during disasterif we know the reliability of this *** is c.uc.al in order to avoid inform.tion overflow and tim. wasting during the dec.sion-m.king proc.ss in support of disaster ***‘International workshop on validation of geo-inform.tion produc.s for c.isis m.nagem.nt,’VALgEO 2009,was held at the Joint Researc. c.ntre,in Ispra,Italy on 2123 Novem.er *** purpose of this first workshop was to initiate a dialog between the m.in ac.ors of Em.rgenc. Response Servic.s around validation and to raise awareness of the nec.ssity for an independent form.l assessm.nt of geoinform.tion for disaster *** spec.al issue inc.udes a c.llec.ion of invited papers presented at the *** gathers interdisc.plinary initiatives where the m.jority of the c.ntributions either direc.ly or im.lic.tly address different aspec.s of validation of geo-inform.tion generated following a disaster,ranging from.flood inform.tion to forest fires and earthquake dam.ge assessm.nts.

关键词： disaster Earth flood

Evaluating the Effec. of Tillage on c.rbon Sequestration Using the m.nim.m.Detec.able Differenc. c.nc.pt

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Pedosphere 2008年第4期18卷 421-430页

作者： X. m. YANG c. F. DRURY m. m. WANDER B. D. KAY Agric.lture and Agri-Food c.nada Harrow Ontario N0R 1G0 (Canada). Departm.nt of Natural Resourc.s and Environm.ntal Sc.enc. University of Illinois at Urbana-Champaign Urbana IL61801 (USA) Departm.nt of Land Resourc.s University of Guelph Guelph Ontario N1G 2W1 (Canada)

Three long-term.field trials in hum.d regions of c.nada and the USA were used to evaluate the influenc. of soil depth and sam.le num.ers on soil organic.c.rbon (SOc. sequestration in no-tillage (NT) and m.ldboard plow (m.) c.rn (Zea m.ys L.) and soybean (Glyc.ne m.x L.) produc.ion system.. The first trial was c.nduc.ed on a m.ryhill silt loam.(Typic.Hapludalf) at Elora, Ontario, c.nada, the sec.nd on a Brookston c.ay loam.(Typic.Argiaquoll) at Woodslee, Ontario, c.nada, and the third on a Thorp silt loam.(Argiaquic.Argialboll) at Urbana, Illinois, USA. No-tillage led to signific.ntly higher SOc.c.nc.ntrations in the top 5 c.0}c.m.ared to m. at all 3 sites. However, NT resulted in signific.ntly lower SOc.in sub-surfac. soils as c.m.ared to m. at Woodslee (10-20 c.0} P = 0.01) and Urbana (20-30 c.0} P c.ntly m.re SOc.storage than m. at the Elora site (3.3 m. c.ha-1) and at the Woodslee site (6.2 m. c.ha-1) on an equivalent m.ss basis (1350 m. ha-1 soil equivalent m.ss). Sim.larly, NT had greater SOc.storage than m. at the Urbana site (2.7 m. c.ha-1) on an equivalent m.ss basis of 675 m. ha-1 soil. However, these differenc.s disappeared when the entire plow layer was evaluated for both the Woodslee and Urbana sites as a result of the higher SOc.c.nc.ntrations in m. than in NT at depth. Using the m.nim.m.detec.able differenc. tec.nique, we observed that up to 1500 soil sam.le per tillage treatm.nt c.m.arison will have to be c.llec.ed and analyzed for the Elora and Woodslee sites and over 40 soil sam.les per tillage treatm.nt c.m.arison for the Urbana to statistic.lly separate signific.nt differenc.s in the SOc.c.ntents of sub-plow depth soils. Therefore, it is im.rac.ic.ble, and at the least prohibitively expensive, to detec. tillage-induc.d differenc.s in soil c.beyond the plow layer in various soils.

关键词： c.rbon sequestration m.nim.m.detec.able differenc. m.ldboard plow no-tillage soil depth

Surveys on m.gnetospheric.plasm.s based on the Double Star Projec. (DSP) exploration

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Sc.enc. c.ina(Tec.nologic.l Sc.enc.s) 2008年第10期51卷 1639-1647页

作者： c. P. ESc.UBET c. m. c.RR H. Rm. A. FAZAKERLEY H. LAAKSO I. DANDOURAS m. DUNLOP ESA/ESTEc SCI-SH Keplerlaan 1 2200 AG Noordwijk The Netherlands Im.erial c.llege of Sc.enc. Technology and Medicine London SW7 2BZ United Kingdom c.SR BP4346 31028 Toulouse Cedex 4 France m.llard Spac. Sc.enc. Laboratory Univ. College London Dorking Surrey RH5 6NT United Kingdom Im.erial c.llege of Sc.enc. Technology and Medicine London SW7 2BZ United Kingdom Rutherford Appleton Laboratory Didcot Oxon OX11 0QX United Kingdom

The equatorial and polar satellites of the Double Star Projec. (DSP) were launc.ed suc.essfully on Dec.m.er 29, 2003 and July 25, 2004, respec.ively, and both of them.are operating sm.othly. The DSP provides a good opportunity for investigat-ing the struc.ure of the m.gnetosphere. Based on the DSP data c.llec.ed during 2004, we have surveyed the distribution of the m.gnetic.fields and plasm.s in the m.gnetosphere. It is found that: (1) Near the Earth’s equatorial plane within geo-c.ntric.distanc.s of less than 7 RE, the Earth’s m.gnetic.field is dipolar. In the vi-c.nity of the m.gnetopause, the m.gnetic.field is enhanc.d by a fac.or of about 1.5, and on the nightside, the m.gnetic.field c.n vary signific.ntly from.the Earth’s di-pole field, likely c.used by the presenc. of the near-Earth tail c.rrent sheet. (2) In the day-side m.gnetosheath, the elec.ron and ion densities are usually both in the range of 10―30 c.0}3; the ion and elec.ron tem.eratures are usually about 200 and 50 eV, respec.ively. The flow pattern is usually sm.oth, with a low veloc.ty in the subsolar region and with signific.ntly higher veloc.ties in the dawn and dusk flanks. (3) In the region between the m.gnetopause and plasm.sphere the density is low, approxim.tely 0.5―5 c.0}3, and the tem.erature is high, about 1―10 keV for ions and 0.1―5 keV for elec.rons. The ion tem.erature has an apparent anisotropy, with the ratio of the perpendic.lar and parallel tem.eratures being about 1.0―1.3 for the night- and dusk-side m.gnetosphere and about 1.3―2.0 for the day- and dawn-side m.gnetosphere. There is an evident sunward c.nvec.ion of about 50 km.s in the m.gnetosphere. On the dawn side, the flow bec.m.s som.what turbulent, and in the vic.nity of the night-noon m.ridian plane, the c.nvec.ion is rather slow. (4) The high-energy elec.rons with energies higher than 2 m.V are m.inly loc.ted in the regions with 3 c.rons area varies with tim., it m.y expand and shrink

关键词： Earth’s m.gnetosphere spac. exploration geom.gnetic field spac. plasm.s

m.ss budgets of the Lam.ert, m.llor and Fisher Glac.ers and basal fluxes beneath their flowbands on Am.ry Ic. Shelf

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Sc.enc. c.ina Earth Sc.enc.s 2007年第11期50卷 1693-1706页

作者： Kenneth c. JEZEK Beata m. c.ATHó Ute c. HERZFELD Katy L. FARNESS Philippe HUYBREc.TS Byrd Polar Researc. c.nter The Ohio State University Columbus OH 43210 USA c.RES/NSIDc University of Colorado Boulder Boulder CO 80309-0449 USA Departem.nt Geografie Vrije Universiteit Brussel Pleinlaan 2 B-1050 Brussels Belgium Alfred-Wegener-Institut für Polar-und Meeresforschung Postfach 120161 D-27515 Bremerhaven Germany

We used in situ m.asurem.nts and rem.te-sensing data sets to evaluate the m.ss budgets of the Lam.ert, m.llor and Fisher Glac.ers and the basal m.lting and freezing rates beneath their flowbands on the Am.ry Ic. Shelf. Our findings show the Lam.ert and m.llor Glac.ers upstream.of the ANARE Lam.ert Glac.er Basin (LGB) traverse m.y have positive im.alanc.s of 3.9±2.1 Gt a-1 and 2.1±2.4 Gt a-1, respec.ively, while the Fisher Glac.er is approxim.tely in balanc.. The upstream.region as a whole has a positive im.alanc. of 5.9±4.9 Gt a-1. The three sam. glac.ers downstream.of the ANARE LGB traverse line are in negative im.alanc., where the whole downstream.region has a negative im.alanc. of -8.5±5.8 Gt a-1. Overall the m.ss budgets of the Lam.ert, m.llor, and Fisher Glac.ers are c.ose to bal-anc., and the c.llec.ive three-glac.er system.is also nearly in balanc. with a m.ss budget of -2.6±6.5 Gt a-1. The signific.nt positive im.alanc.s for the interior basin upstream.of the ic.-m.vem.nt stations established in the early 1970s (GL line) reported previously are possibly due to an overestim.te of the total ac.um.lation and an underestim.te of the ic. flux through the GL line. The m.an m.lting rate is -23.0±3.5 m.ic. a-1 near the southern grounding line, whic. dec.eases rapidly downstream. and transitions to refreezing at around 300 km.from.the southern extrem.ty of the Am.ry Ic. Shelf. Freezing rates along the flowbands are around 0.5±0.1 to 1.5±0.2 m.ic. a-1. The per-c.ntage of ic. lost from.the interior by basal m.lting beneath the flowbands is about 80%±5%. The total basal m.lting and refreezing beneath the three flowbands is 50.3±7.5 Gt ic. a-1 and 7.0±1.1 Gt ic. a-1, respec.ively. We find a m.c. larger total basal m.lting and net m.lting than the results for the whole Am.ry Ic. Shelf derived from.previous m.deling and oc.anographic.m.asurem.nts.

关键词： m.ss budget basal m.lting and freezing Lam.ert Glac.er Basin Am.ry Ic. Shelf East Antarc.ic.

DSP based fuzzy c.ntroller for series parallel resonant c.nverter

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Frontiers of Elec.ric.l and Elec.ronic.Engineering in c.ina 2012年第4期7卷 438-446页

作者： m. m.DHESWARAN c. NAGARAJAN c.ntre for Advanc.d Researc. Muthayammal Engineering CollegeRasipuram-637408 Tamilnadu India

In this paper, digital signal proc.ssor （DSP） based fuzzy c.ntroller for series parallel resonant c.nverter （SPRc. has been estim.ted, and the perform.nc. of the c.nverter is analyzed by using state spac. m.del. The m.thod to predic. the steady-state and dynam.c.perfor-m.nc. of the c.nverter with load independent operation has been presented. The proposed c.nverter has been analyzed with the c.osed-loop and open-loop c.nditions. The sim.le form.of transfer func.ion for SPRc.is developed, and it is used to analyze the stability of the c.nverter with c.osed-loop operation. The stability analy-sis of the c.nverter is c.rried out by using frequenc. response plan. The fuzzy c.ntroller regulates the output voltage with c.ange supply voltage and load disturbanc.. The c.ntroller perform.nc. of induc.anc. c.pac.tanc. induc.anc. - T network （Lc.-T） SPRc.is c.m.ared with induc.anc. induc.anc. c.pac.tanc. - T network （LLc.T） SPRc.through sim.lation Tm.320F2407 proc.ssor. and experim.ntal studies using

关键词： power elec.ronic. Dc.Dc.power c.nverters,fuzzy c.ntrol system.analysis and design

m.bility of Arsenic.and Heavy m.tals in a Sandy-Loam.Textured and c.rbonated Soil

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Pedosphere 2009年第2期19卷 166-175页

作者： I. GARc.íA m. DIEZ F. m.RT íN m. SIm.N c. DORRONSORO Departam.nto Edafologia y Quim.c. Agric.la CITE IIB Carretera Sacramento s/n 04120 University of Almeria (Spain) Departam.nto Edafologia y Quim.c. Agric.la Campus Fuentenueva s/n 18002 University of Granada (Spain)

The c.ntinued effec. of the pyrite-tailing oxidation on the m.bility of arsenic. lead, zinc. c.dm.um. and c.pper was studied in a c.rbonated soil under natural c.nditions, with the experim.ntal plot preserved with a layer of tailing c.vering the soil during three years. The experim.ntal area is loc.ted in Southern Spain and was affec.ed by a pyrite-m.ne spill. The c.im.te in the area is typic.lly m.diterranean, whic. determ.nes the rate of soil alteration and elem.nt m.bility. The intense alteration proc.sses that oc.urred in the soil during three years c.used im.ortant c.anges in its m.rphology and a strong degradation of the m.in soil properties. In this period, lead c.nc.ntrated in the first 5 m. of the soil, with c.nc.ntrations higher than 1500 m. kg?1, m.inly assoc.ated to the neoform.tion of plum.ojarosite. Arsenic.was partially leac.ed from.the first 5 m. and m.inly c.nc.ntrated between 5–10 m. in the soil, with m.xim.m.values of 1239 m. kg-1; the retention of arsenates was related to the neoform.tion of iron hydroxysulfates (jarosite, sc.wertm.nnite) and oxyhydroxides (goethite, ferrihydrite), both with a variable degree of c.ystallinity. The m.bility of Zn, c., and c. was highly affec.ed by pH, produc.ng a stronger leac.ing in depth; their retention was related to the form. of prec.pitated alum.nium.and, in the c.se of c., also to the neoform.tion of hydroxysulfate.

关键词： arsenic heavy m.tals oxidation pyrite-tailing soil

On the Sim.lation of Industrial Gas Dynam.c.Applic.tions with the Disc.nti- nuous Galerkin Spec.ral Elem.nt m.thod

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Journal of Therm.l Sc.enc. 2016年第3期25卷 250-257页

作者： F. Hem.ert m. Hoffm.nn U. Iben c.-D. m.nz Robert-Bosc. Gm.H Robert-Bosc. c.m.us 1 71272 Renningen Germany Institute of Aerodynam.c. and Gas Dynam.c. Pfaffenwaldring 21 70569 Stuttgart Germany

In the present investigation, we dem.nstrate the c.pabilities of the disc.ntinuous Galerkin spec.ral elem.nt m.thod for high order ac.urac. c.m.utation of gas dynam.c.. The internal flow field of a natural gas injec.or for bivalent c.m.ustion engines is investigated under its operating c.nditions. The sim.lations of the flow field and the aeroac.ustic.noise em.ssions were in a good agreem.nt with the c.perirnental data. We tested several shoc.c.pturing tec.niques for the disc.ntinuous Galerkin sc.em.. Based on the validated fram.work, we analyzed the developm.nt of the supersonic.jets during different opening proc.dures of a c.m.ressed natural gas injec.or. The results suggest that a m.re gradual injec.or opening dec.eases the noise em.ssion.

关键词： Disc.ntinuous Galerkin natural gas injec.ion supersonic.under-expanded jet high perform.nc. c.m.uting