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a.plica.ion of Wea.est Link Proba.ilistic Fra.ework for Fa.igue Notch Fa.tor to Turbine Engine Ma.eria.s

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World Journa. of Mecha.ics 2013年第5期3卷 237-244页

作者： Oluwa.a.owa.a. Okeyoyin Gba.ebo M. Owola.i Depa.tment of Mecha.ica. Engineering Howard University Washington DC USA

This pa.er is concerned with the extension of a.recently developed proba.ilistic fra.ework ba.ed on Weibull’s wea.est link a.d extreme-va.ue sta.istics to a.ro-engine ma.eria.s like tita.ium a.loy a.d nickel-ba.e super a.loys using simula.ion stra.egies tha. ca.ture both the essence of notch root stress gra.ient a.d the complexity of rea.istic microstructures. In this pa.er, notch size effects a.d notch root inela.tic beha.ior a.e combined with proba.ility distributions of microsca.e stress-stra.n gra.ient a.d sma.l cra.k initia.ion to inform minimum life design methods. a.new a.proa.h which ca. be a.plied using crysta. pla.ticity finite element or closed-form solution is a.so proposed a. a.more robust a.proa.h for determining fa.igue notch fa.tor tha. the existing cla.sica. methods. The fa.igue notch fa.tors predicted using the new fra.ework a.e in good a.reements with experimenta. results obta.ned from litera.ure for notched tita.ium a.loy specimens subjected to unia.ia. cyclic loa.s with va.ious stress ra.io.

关键词： Microstructure Fa.igue Cra.k Initia.ion Crysta. Pla.ticity

Growth Kinetics of Wildlife <i>E. coli</i>Isola.es in Soil a.d Wa.er

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Journa. of Environmenta. Protection 2012年第8期3卷 838-846页

作者： Megha. a. Ga.la.her Ra.hupa.hy Ka.thikeya. Sa.ib Mukhta. Biologica. a.d a.ricultura. Engineering Depa.tment Texa. a.M University College Station TX Biologica. a.d a.ricultura. Engineering Depa.tment Texa. a.M University College Station TX.

Ba.teria.a.e the ma.or ca.se of surfa.e wa.er conta.ina.ion in the United Sta.es. US Environmenta. Protection a.ency (USEPa. uses the Tota. Ma.imum Da.ly Loa. (TMDL) process to regula.e the E. coli loa.s from feca. sources in a.wa.ershed. Different point a.d non-point sources ca. contribute to the feca. conta.ina.ion of a.wa.erbody including municipa. a.d on-site wa.tewa.er trea.ment pla.ts, livestock, birds, a.d wildlife. Unfortuna.ely, wildlife sources in ma.y rura. wa.ersheds a.e poorly cha.a.terized. E. coli is a.so known to persist in wa.erbodies when no known feca. sources a.e present. In this study, E. coli from wildlife feca. ma.eria. wa. enumera.ed a.d the fa.e of E. coli under different environmenta. fa.tors wa. studied. No growth wa. observed in soil a. 4% moisture content a.d in wa.er a. 10℃. The highest E. coli growth wa. recorded in wa.er a. 30℃. It ca. be seen from these results tha. there wa. va.ia.ion in the fa.e of E. coli under different environmenta. conditions. The fa.e of E. coli in the environment is a.complex process a.d is influenced by ma.y fa.tors a.d their intera.tions, ma.ing it difficult to predict. The findings from this study a.ong with a.ditiona. studies ca. be used to improve the a.cura.y of model predictions to estima.e the E. coli loa.s in wa.ersheds.

关键词： Ba.teria Feca. Conta.ina.ion TMDL Wa.er Qua.ity

Physics Ba.e &a.p;Conceptua. Views Complex of Ba.l Lightning

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Journa. of Modern Physics 2010年第4期1卷 251-275页

作者： a.ton V. Pinchuk Vla.imir a. Pinchuk 不详

The complex of conceptua. views a.out ba.l lightning (BL) a. conta.ning surplus electrica. cha.ge qua.i- sta.iona.y ma.eria. founda.ion with distinctions between levels of tra.sla.ion tempera.ure a.d exciting tem- pera.ures of chemica. bonds a.d electron energy sta.es ha. been offered a.d is substa.tia.ed in the pa.er. The being formed complex is grounded upon overstepping the limits of genera.ly a.cepted physica. ba.e a.d is a.med a. a.l-round substa.tia.ion of jointly observed in na.ure ma.ifesta.ions of BL. Within the limits of the being formed complex the possibility of loca.iza.ion of ba.l lightning in a.rspa.e is confirmed. The na.ure of the one’s ra.ia.e ca.a.ity is substa.tia.ed. The role of environment a. source tha. feeds BL with energy is esta.lished. Power supply mecha.isms, conditions a.d peculia.ities of BL’s cha.a.teristics reproduction through lifetime a.e specified. The forma.ions cha.nels of energy resources of BL a.e turned out. Levels of BL’s energy potentia.ities, both permissibility proper a.d wide dia.a.on of va.ia.ion of the ones (multi-fa.es of ba.l lightning) a. well a. the ca.a.ility of BL to overcome a.y ba.riers from dielectric ma.eria.s by mea.s of penetra.ion through ina.es in body of ba.riers a.d then to restore the one’s cha.a.teristic (octopus’s effect) a.e substa.tia.ed. a.equa.y of being formula.ed conceptua. views a. a.whole is confirmed.

关键词： Ba.l Lightning Na.ura. a.oma.y

a.Ra.a. Visua.iza.ion System Upgra.e

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Journa. of Softwa.e Engineering a.d a.plica.ions 2010年第2期3卷 150-159页

作者： Hector N. a.osta.Ma.celo a. Tosini 不详

This work develops a.system to visua.ize the informa.ion for ra.a. systems interfa.es. It is a.flexible, porta.le softwa.e system tha. a.lows to be used for ra.a.s tha. ha.e different technologies a.d tha. is a.le to be a.a.ted to the specific needs of ea.h a.plica.ion doma.n in a. efficient wa.. Repla.ing the visua.iza.ion a.d processing units on existing ra.a. pla.forms by this new system, a.pra.tica. a.d inexpensive improvement is a.hieved.

关键词： Ra.a. Da.a Visua.iza.ion Signa. Processing Signa. Pa.tern Recognition

Synthesis, Cha.a.teriza.ion, Crysta. Studies of (E)-3-(3-(4-Fluorophenyl)-1-isopropyl-1H-indol-2-yl) a.ryla.dehyde

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Crysta. Structure Theory a.d a.plica.ions 2013年第4期2卷 148-154页

作者： Veerendra.Kuma. a. Ka.a.ba.di J. Seetha.a.a.pa Depa.tment of Chemistry Karnatak University Dharwad India

We ha.e synthesized a.d developed single crysta.s of the title compound (E)-3-(3-(4-fluorophenyl)-1-isopropyl-1H-indol-2-yl) a.ryla.dehyde, which is a.key intermedia.e of a.ti-cholesterol fluva.ta.in drug. It crysta.lized under orthorhombic system with a.spa.e group Pna.1. The dihedra. a.gle between the indole mea. pla.e a.d 4-F-phenyl ring wa. observed to be 111.5 (3)° in the title molecule. Further, strong hydrogen bonds were not found in the crysta. structure.

关键词： Single Crysta. Structure X-Ra. Diffra.tion Intermedia.e of Fluva.ta.in Indoles

Vola.ility Modelling of Globa. Fina.cia. Crises Effects on the Nigeria. Ba.ks

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Open Journa. of Sta.istics 2020年第2期10卷 303-324页

作者： Ma.uf a. Ra.eem Timothy K. Sa.son Depa.tment of a.d Engineering a.d Ma.hema.ics Sheffield Hallam University Sheffield United Kingdom Depa.tment of Sta.istics University of Uyo Uyo Nigeria Sta.istics Progra.me College of Engineering Agriculture and Science Bowen University Iwo Osun State Nigeria

The most a.propria.e heteroskeda.tic models for predicting vola.ility of da.ly stocks prices of 10 ma.or Nigeria. ba.ks a.e proposed. The ba.ks a.e a.cess, United Ba.k for a.rica.(UBa., Gua.a.ty Trust, Skye, Dia.ond, Fidelity, Sterling,?Union, ETI a.d Zenith ba.ks;a.d these a.e exa.ined from 2004 to 2014.?The models employed a.e a.toregressive Conditiona. Heterosceda.tic (a.CH(1)), Genera.ized a.toregressive Conditiona. Heterosceda.tic (Ga.CH(1, 1)),?Exponentia. Genera.ized a.toregressive Conditiona. Heterosceda.tic?(EGa.CH(1, 1))?a.d Glosten, Ja.a.a.tha. a.d Runkle-Genera.ized a.toregressive Conditiona. Heterosceda.tic?(GJR-Ga.CH(1, 1)). The results show tha. a.l the?ba.k returns a.e highly leptokurtic, significa.tly skewed a.d thus non-norma. a.ross the four periods except for Fidelity ba.k during fina.cia. crises;findings simila. to those of other globa. ma.kets. a.so noticed is the strong evidence for the presence of heterosceda.ticity, a.d tha. vola.ility persistence during crisis?is?higher tha. before the crisis a.ross the 10 ba.ks, with tha. of UBa.ta.ing the lea., a.out 11 times higher during the crisis. The sa.e with persistence?levels in vola.ility, which were rela.ively higher during fina.cia. crises a.ross the ten ba.ks compa.ed to before the crises.?Findings further indica.e tha. a.ymmetric Ga.CH models outperformed the symmetric Ga.CH models, especia.ly during the fina.cia. crises a.d post the crises. Thus with these findings, one could genera.ly conclude tha. Nigeria. ba.ks’?returns a.e vola.ility persistent during a.d a.ter the crises, a.d a.e cha.a.terized by levera.e effects of nega.ive a.d positive shocks during these periods.

关键词： Globa. Fina.cia. Crisis Levera.e Effect Nigeria. Stock Excha.ge Vola.ility Clustering Persistence

a.proxima.e Reformula.ion a.Recent Non-Renorma.iza.le QFT’s Methodology a.d Einstein’s Gra.ity

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Journa. of High Energy Physics, Gra.ita.ion a.d Cosmology 2020年第2期6卷 298-311页

作者： a. Pla.tino M. C. Rocca Depa.ta.ento de Fisica Universidad Nacional de La Plata Argentina Consejo Na.iona. de Investiga.iones Científica. y Tecnológica. (IFLP-CCT-CONICET)-C. C. 727 La Plata Argentina STha.-EPFL Lausanne Switzerland Depa.ta.ento de Ma.emática Universidad Nacional de La Plata Argentina

We revisit, a.va.cing a.useful a.proxima.ion, a.recently formula.ed QFT trea.ment tha. successfully overcomes a.y troubles with infinities for non-renorma.iza.le QFTs [J. Phys. Comm. 2 115029 (2018)]. Such methodology wa. a.le to successfully dea., in non-rela.ivistic fa.hion, with Newton’s gra.ita.ion potentia. [a.na.s of Physics 412, 168013 (2020)]. Our present a.proxima.ion to the QFT method of [J. Phys. Comm. 2 115029 (2018)] is ba.ed on the Einstein’s La.ra.gia. (EG) ela.ora.ed by Gupta.[1], sa.e for a.different constra.nt’s selection. This choice a.lows one to a.oid the la.k of unita.ity for the S ma.rix tha. impa.red the proceedings of Gupta.a.d Feynma.. Moreover, we a.e a.le to simplify the ha.dling of such constra.nt by elimina.ing the need to involve ghosts for gua.a.tying unita.ity. Our a.proxima.ion consists in setting the gra.iton field ∅μν=&ga.ma.μν∅, where &ga.ma.μνis a.consta.t tensor a.d ∅a.sca.a. (gra.iton) field. The ensuing a.proxima.e a.proa.h is non-renorma.iza.le, a. inconvenience tha. we a.e a.le to overcome in [J. Phys. Comm. 2 115029 (2018)].

关键词： Qua.tum Field Theory Einstein Gra.ity Non-Renorma.iza.le Theories Unita.ity

Inverter-Ba.ed Diesel Genera.or Emula.or for the Study of Frequency Va.ia.ions in a.La.ora.ory-Sca.e a.tonomous Power System

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Energy a.d Power Engineering 2013年第3期5卷 274-283页

作者： Miguel Torres Luiz a. C. Lopes Depa.tment of Electrica. a.d Computer Engineering Concordia University Montreal Canada

This pa.er presents the modeling, simula.ion a.d pra.tica. implementa.ion of a. inverter-ba.ed diesel genera.or emula.or. The ma.n purpose of this emula.or is for the study of frequency va.ia.ions in diesel-ba.ed a.tonomous power systems in a.la.ora.ory environment where the opera.ion of a.rea. diesel genera.or is not possible. The emula.or ba.ica.ly consists in a.volta.e source inverter with a.second order output filter which volta.e references a.e given by the model of the diesel genera.or. The control of the emula.or is ba.ed on the digita. signa. processor TMS320F2812, where the ma.hema.ica. models of the diesel genera.or a.d the control of the inverter a.e computed in rea.-time. Pa.a.eters for the model were obta.ned from commercia.ly a.a.la.le components. Experimenta. results for different va.ues of speed droop showed tha. the emula.or a.hieves a.sa.isfa.tory performa.ce in the tra.sient a.d sta.iona.y response. For the sta.iona.y response, the mea.ured frequency devia.es from theoretica. va.ues with a.mea. a.solute error of: 0.06 Hz for 0% droop, 0.037 Hz for 3% droop, a.d 0.087 Hz for 5% droop. For the tra.sient response, the mea.ured frequency na.ir devia.es from simula.ions in: 0.05 Hz for 0% droop, 0.02 Hz for 3% droop, a.d 0.1 Hz for 5% droop.

关键词： Diesel Genera.or Emula.or Inverter Frequency Control Mini-Grid

Numerica. Modelling Sediment-Ba.teria.Intera.tion Processes in the Severn Estua.y

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Journa. of Wa.er Resource a.d Protection 2011年第1期3卷 22-31页

作者： Gua.gha. Ga. Roger a. Fa.coner Binlia.g Lin 不详

Fa.ca. ba.teria.exist in both free-living a.d a.ta.hed forms in estua.ine wa.ers. The deposition of sediments ca. ta.e fa.ca. ba.teria.out of the wa.er column a.d to the bed. The sediments ca. subsequently be re-suspended to the wa.er column, which ca. then lea. to re-suspension of the fa.ca. ba.teria.of the a.ta.hed forms ba.k to the wa.er column. Therefore, the fa.e a.d tra.sport of fa.ca. ba.teria.is highly rela.ed to the governing sediment tra.sport processes, pa.ticula.ly where these processes a.e significa.t, such a. the Severn Estua.y, UK. However, little a.tempt ha. been ma.e to model such processes in terms of predicting the impa.t of the sediment fluxes on fa.ca. ba.teria.levels. Deta.ls a.e given of the refinement of a.numerica. model of fa.ca. ba.teria.tra.sport, where the sediment tra.sport processes a.e significa.t. a.ter testing the sediment-ba.teria.intera.tion model fa.oura.ly a.a.nst known results in previous study, the model wa. a.plied to the Severn Estua.y a.d Bristol Cha.nel, UK, to investiga.e the impa.t of suspended sediment fluxes on the corresponding fa.ca. ba.teria.tra.sport processes. The model predictions ha.e proved to be encoura.ing, with the results being compa.ed to a.tra.itiona. fa.ca. ba.teria.modelling a.proa.h, where sediment ba.teria.intera.tions were not included. The new model provides improved predictions of fa.ca. ba.teria.concentra.ions when sediment tra.sport is included a.d for the Bristol Cha.nel Severn Estua.y it ca. be seen tha. the effects of the sediments on the ba.teria. levels in the wa.er column ca. be significa.t.

关键词： Numerica. Modelling Fa.ca. Ba.teria Sediment Tra.sport Enterococci