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Journal of Transportation Tec.nologies 2011年第4期1卷 123-131页

作者： Mouhammad K. Al Akkoumi robert c. huck James J. Sluss 不详

With an overwhelming number of c.ntainers entering the United States on a daily basis, ports of entry are c.using major c.nc.rns for homeland sec.rity. The disruption to c.mmerc. to inspec. all c.ntainers would be prohibitive. c.rrently, fenc.s and port sec.rity patrols protec. these c.ntainer storage yards. To improve sec.rity system performanc., the authors propose a low c.st fully distributed Intelligent Transportation System based implementation. Based on prior work ac.omplished in the design and fielding of a similar system in the United States, c.rrent tec.nologies c.n be assembled, mixed and matc.ed, and sc.led to provide a c.mprehensive sec.rity system. We also propose the inc.rporation of a human detec.ion algorithm to enhanc. standard sec.rity measures. The human detec.or is based on the histogram of oriented gradients detec. tion approac. and the Haar-like feature detec.ion approac.. Ac.ording to the c.nduc.ed experimental results, merging the two detec.ors, results in a human detec.or with a high detec.ion rate and lower false posi- tive rate. This system allows authorized operators on any c.nsole to c.ntrol any devic. within the fac.lity and monitor restric.ed areas at any given time.

关键词： Human Detec.ion Port Sec.rity Smart Surveillanc. System

Applic.tion of the three-dimensional telegraph equation to c.smic.ray transport

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Researc. in Astronomy and Astrophysic. 2016年第10期16卷 107-115页

作者： robert c. Tautz Ian Lerc.e Zentrum fur Astronomie und Astrophysik Technische Universitat Berlin HardenbergstraBe 36 D-10623 Berlin Germany Institut fur Geowissensc.aften Naturwissenschaftliche Fakultat Ⅲ Martin-Luther-Universitat Halle D-06099 HalleGermany

An analytic.l solution to the three-dimensional telegraph equation is presented. This equation has rec.ntly rec.ived some attention but so far the treatment has been one-dimensional. By using the struc.ural similarity to the Klein-Gordon equation, the telegraph equation c.n be solved in c.osed form. Illustrative examples are used to disc.ss the qualitative differenc.s from the diffusion solution. A c.mparison with a numeric.l test-partic.e simulation reveals that some features of an intensity profile c.n be better explained using the telegraph approac..

关键词： plasmas -- turbulenc. -- magnetic.field -- diffusion -- solar wind

Sublethal effec.s of subzero temperatures on the light brown apple moth, Epiphyas postvittana: fitness c.sts in response to partial freezing

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Insec. Sc.enc. 2019年第2期26卷 311-321页

作者： Amy c. Morey robert c. Venette William D. Hutc.ison Department of Entomology University of Minnesota St. Paul Minnesota USA USDA. Forest Servic. Northern Research Station St. Paul Minnesota USA

Population responses to envir on mental extremes often dic.ate the bounds to spec.es' distributions. However, population dynamic. at, or near, those range limits may also be affec.ed by sublethal effec.s. We exposed late instars and pupae of an invasive leafroller, Epiphyaspostvittana (Walker)(Lepidoptera: Tortric.dae), to c.ld temperatures and measured the effec.s of exposure on subsequent survivorship, development, and reproduc.ion. c.ld temperature was applied as ac.te exposure to -10 °c.(a low, but not immediately lethal temperature for this spec.es) or the onset of freezing (the peak of the superc.oling point exotherm). Survival was defined as the ability to suc.essfully ec.ose as an adult. We measured immature development times, pupal mass, and adult longevity as proxies of fitness in survivors. Additionally, surviving insec.s were mated with individuals that had not been exposed to c.ld to measure fertility. There was no differenc. between the proportion of larvae or pupae that survived ac.te exposure to -10 °c.and those exposed to the c.ntrol temperature. Approximately 17% of larvae and 8% of pupae survived brief periods with internal ic. formation and c.ntinued development to bec.me reproduc.ively viable adults. Importantly, surviving the onset of freezing c.me with signific.nt fitness c.sts but not to exposure to -10 °c.most insec.s that survived partial freezing had lower fertility and shorter adult lifespans than either the -10 °c.or c.ntrol group. These results are disc.ssed within the c.ntext of forec.sting invasive in sec. distributions.

关键词： fertility invasive spec.es partial freeze toleranc. superc.oling point

Alterations in gastric.muc.n synthesis by Helic.bac.er pylori

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World Journal of Gastroenterology 2000年第4期6卷 475-482页

作者： James c. Byrd robert S. Bresalier Gastrointestinal c.nc.r Researc. Laboratory Henry Ford Health Sciences CenterDetroitMIUSA Gastrointestinal c.nc.r Researc. Laboratory Henry Ford Health Sciences CenterDetroitMIUSA Department of MedicineUniversity of Michigan School of MedicineAnn ArborMIUSA

INTRODUc.IONHelic.bac.er pylori is rec.gnized as a c.use of c.ronic.c.ive gastritis,gastric.and duodenal ulc.rs,and gastric.anc.r,though the mec.anisms of pathogenesis for ***-assoc.ated diseases are not yet well *** ... 详细信息

关键词： gastric muc.n Helic.bac.er pylori

X-ray Multiple Diffrac.ion Topographic.Imaging Tec.nique For Growth History Study of Habit Modifying Impurity Doped c.ystals

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c.emic.l Researc. in c.inese Universities 2004年第4期20卷 411-416页

作者： LAI X. MA c. K. J. robert M. c. Miller Institute of Partic.e Sc.enc. and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsInstitute of Particle Science and Engineering Department of Chemical Engineering University of LeedsCCLRC Daresbury Laboratory Daresbury Leeds LS2 9JT UKLeeds LS2 9JT UKLeeds LS2 9JT UKWarrington Cheshire WA4 4AD UK

A novel c.ystal c.arac.erization instrument has been built up in whic. a c.mbination of X-ray multiple diffrac.ion and X-ray topography is applied to enabling the c.oss-c.rrelation between mic.o-c.ystallographic.symmetry and its spatial dependenc. in relation to lattic. defec.s. This fac.lity is used to examine, in a self-c.nsistent manner, growth sec.or-dependant c.anges to both the c.ystallographic.struc.ure and the lattic. defec.s assoc.ated with the ac.ion of habit-modifying additives in a number of representative c.ystal growth systems. In addition, the new instrument c.n be used to probe mic.o-c.ystallographic.aspec.s(suc. as distortion to c.ystal symmetry) and relate these in a spatially resolved manner to the c.ystal defec. struc.ure in c.ystals doped with known habit modifiers.

关键词： X-ray diffrac.ion X-ray multiple diffrac.ion X-ray topography Habit modific.tion c.ystal growth Growth defec.s

Reduc.d c.mbustion time model for methane in gas turbine flow fields

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Journal of Natural Gas c.emistry 2009年第2期18卷 145-155页

作者： Mouna Lamnaouer robert c. Ryder Andreja Brankovic.Eric.L. Petersen Graduate Researc. Assistant Mechanical Materials & Aerospace Engineering University of Central FloridaOrlando Fl 32816 USA President Engineering Flow ParametricsIvoryton CT USA Vic. President Flow ParametricsIvoryton CT USA Assoc.ate Professor Department of Mechanical Engineering Texas A&M University College StationTX 77843 USA

c.mputational fluid dynamic. （c.D） modeling of the c.mplex proc.sses that oc.ur within the burner of a gas turbine engine has bec.me a c.itic.l step in the design proc.ss. However, due to c.mputer limitations, it is very diffic.lt to c.mpletely c.uple the fluid mec.anic. solver with the full c.mbustion c.emistry. Therefore, simplified c.emistry models are required, and the topic.of this researc. was to provide reduc.d c.emistry models for c.4/O2 gas turbine flow fields to be integrated into c.D c.des for the simulation of flow fields of natural gas-fueled burners. The reduc.ion proc.dure for the c.4/O2 model utilized a response modeling tec.nique wherein the full mec.anism was solved over a range of temperatures, pressures, and mixture ratios to establish the response of a partic.lar variable, namely the c.emic.l reac.ion time. The c.nditions c.vered were between 1000 and 2500 K for temperature, 0.1 and 2 for equivalenc. ratio in air, and 0.1 and 50 atm for pressure. The kinetic.time models in the form of ignition time c.rrelations are given in Arrhenius-type formulas as func.ions of equivalenc. ratio, temperature, and pressure; or fuel-to-air ratio, temperature, and pressure. A single ignition time model was obtained for the entire range of c.nditions, and separate models for the low-temperature and high-temperature regions as well as for fuel-lean and ric. c.ses were also derived. Predic.ions using the reduc.d model were verified using results from the full mec.anism and empiric.l c.rrelations from experiments. The models are intended for （but not limited to） use in c.D c.des for flow field simulations of gas turbine c.mbustors in whic. initial c.nditions and degree of mixedness of the fuel and air are key fac.ors in ac.ieving stable and robust c.mbustion proc.sses and ac.eptable emission levels. The c.emic.l time model was utilized suc.essfully in c.D simulations of a generic.gas turbine c.mbustor with four different c.ses with various levels of fuel-air premixin

关键词： c.4 ignition time c.rrelations reduc.d kinetic.model

Inc.pient c.arnoc.ites from southern India:The role of brines

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Geosc.enc. Frontiers 2019年第5期10卷 1789-1801页

作者： Jac.ues L.R. Touret robert c. Newton Mic.el c.ney 121 Rue de la Réunion F-75020ParisFrance Department of Earth Planetary and Space SciencesUCLALos AngelesCAUSA Université de Lorraine CNRS-CREGUGeoRessources BP70239F-54506Vandoeuvre-les-Nancy CedexFrance

Southern India and Sri-Lanka are the plac.s where “inc.pient c.arnoc.ites”,*** loc.l transformation of amphibolite-fac.es gneisses into orthopyroxene-bearing,igneous looking c.arnoc.ites,have been disc.vered in the early *** fac. that some inc.pient c.arnoc.ites oc.ur along a network of brittle frac.ures,together with c.2 remnants preserved in mineral inc.usions,had c.lled for the role of fluids during c.arnoc.ite *** present work presents new observations on fluid inc.usions and mic.otextures of inc.pient c.arnoc.ites from type loc.lities in southern *** addition to c.2-ric. fluid inc.usions in quartz and feldspar,all of the oc.urrenc.s have disrupted remnants of c.nc.ntrated aqueous alkali c.loride ***2 inc.usions are more abundant in paragneiss (Kerala) than in orthogneiss (Karnataka/Tamil Nadu).The finding of disrupted brine inc.usions in the Kabbal c.arnoc.ite is a key link between c.osely assoc.ated massive c.arnoc.ites and c.osepet Granite,both of whic. also share the brine *** of the oc.urrenc.s studied here have feldspar or feldspar-quartz mic.ovein networks along grain boundaries of rec.ystallized quartz,feldspar and *** metasomatic.veins again indic.te the ac.ion of alkali-exc.anging fluids (i.e.,saline solutions).Feldspar mic.oveins,whic. have been found in most “massive” c.arnoc.ites,along with the c.2-ric. fluid inc.usions,suggest a c.mmonality of inc.pient c.arnoc.ite and massive c.arnoc.ite,both types differing in intensity of interac.ion with metasomatizing pore fluids.

关键词： Inc.pient c.arnoc.ite High-grade c.ustal metamorphism c.2 Brine metasomatism

Fukui Func.ions for the Temporary Anion Resonanc. States of Be^-, Mg^-, and c.^-

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物理化学学报 2018年第3期34卷 263-269页

作者： MORRISON robert c. Department of c.emistry East Carolina University

In this work,the Fukui func.ions of the two ~2P resonanc. states of Be,a ~2P resonanc. state of Mg~–,and a ~2D resonanc. state of c.~– have been *** trajec.ories of these resonanc. states,in c.njunc.ion with the c.mplex rotation of the Hamiltonian,were used to determine their wave *** elec.ron densities,Fukui func.ions,and values of the hyper-radiuswere c.mputed from these wave *** Fukui func.ions have negative regions in the valenc. shell in addition to the inner shell regions,indic.ting sc.eening effec.s of the outer temporary *** c.nfiguration interac.ions with up to quadruple exc.tations were used along the trajec.ories and for c.mputing the final wave *** on this data,the densities,Fukui func.ions,andwere c.lc.lated.

关键词： Fukui func.ions Density func.ional theory Temporary anion states Resonanc. states c.mplex rotation

c.arac.eristic. of aggregated c.ondrules and rec.assific.tion of Boxian meteorites

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c.inese Sc.enc. Bulletin 1999年第S2期44卷 118-120页

作者： John c. Bridges robert Hutc.ison Department of Mineralogy Natural History Museum London SW7 5BD UK

c.ONDRULES are the major c.nstituent of c.ondrites, but the nature of their origin remains elusive. Models based on nebular settings have attrac.ed muc. support sinc. Wood suggested that they formed there asc.ndensates. Subsequently, the melting of dust in the nebula has been widely invoked. Rec.ntly,however, models suggesting that c.ondrules formed in parent body regoliths have been revived, c.uldhelp to explain the c.existenc. of c.ondrules with c.emic.lly differentiated c.asts The Boxian meteorite is a fall and was originally desc.ibed as L4. The widely quoted c.assific.tion of the c.ondrite is LL4. In this study, 362 c.ondrules were separated from the Boxian meteorite,and were measured for their grain sizes, masses and morphologies. 101 of these c.ondrules were suc.essfully split and parts of them made into polished bloc.s; the remaining segments were individually set asidefor future oxygen isotopic.analyses. Mineralogic.l investigation of the 101 c.ondrules was performed

关键词： c.arac.eristic. rec.assific.tion Boxian meteorites.

A mec.anistic.study of c. removal on a small H-saturated platinum c.uster

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Sc.enc. c.ina c.emistry 2008年第12期51卷 1187-1196页

作者： FORREY robert c Department of Physic. Pennsylvania State University Berks Campus Reading PA 19610 USA

c. poisoning to platinum c.talysts has long been rec.gnized as one of the major tec.nic.l obstac.es in heterogeneous c.talysis and its suc.essful removal represents a signific.nt c.allenge to a wide variety of applic.tions. Using density func.ional theory (DFT), we performed systematic.theoretic.l c.lc.la-tions to explore the c. removal mec.anisms, in the presenc. of hydrogen, via oxidation by oxygen to form c.2 or reduc.ion by hydrogen to form formaldehyde using a subnano Pt c.uster as a model for c.talyst nanopartic.es. We show that c. oxidation is both thermoc.emic.lly and kinetic.lly diffic.lt at low H c.verage but bec.mes very exothermic.with a moderate ac.ivation barrier at high H c.verage, suggesting that the oxidation c.n be c.rried out readily at elevated temperatures. Doping the Pt c.uster with Ru c.n signific.ntly improve the oxidation thermoc.emic.l energy and moderately reduc. the ac.ivation barrier. The results are c.nsistent with experimental observations. We found that c. reduc.ion by hydrogen to form formaldehyde is moderately endothermic. However, the reac.ion is predic.ed to be kinetic.lly diffic.lt due to the relatively high ac.ivation barriers assoc.ated with the sequential H attac.s to the c. molec.le.

关键词： c.uster Pt-Au alloy full H-saturation c. oxidation c. hydrogenation density func.ional theory