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951.
J.H.HAN A.J.I.WARD B.K.LAVINE Department of Chemistry Clarkson University Potsdum NY U.S.A. 《地理学报(英文版)》1990,(1)
Because many pattern recognition techniques are predicated on the assumption of mutivariate normaldata,Monte Carlo simulation studies were performed to determine the number of samples that arenecessary to describe a multivariate normal population adequately.From these studies we have learnedthat hundreds of sainples are required.These results suggest that parametric procedures should only beused to analyze very large data sets. 相似文献
952.
PAUL BENJAMIN CRILLY Department of Electrical Computer Engineering Knoxville TN - U.S.A. 《地理学报(英文版)》1990,(1)
In previous papers Jansson's method was found to be successful at deconvolving severely overlapped gaschromatographic peaks.In the most recent paper the method was evaluated with respect to quantitativeaceuracy,peak area and retention time repeatability.The problems associated with deconvolving noisydata and some alternatives which can improve the ability of Jansson's method to deconvolve noisy dataare discussed.These alternatives include presmoothing the data with a nine-point,third-order polynomialfilter and data reblurring.This paper will test these methods on peaks with various degrees of resolutionand signal-to-noise ratios. 相似文献
953.
954.
T.S.Spassova 《大气科学进展》1992,(2)
A previously developed model of a 2-dimensional air flow with constant horizontal shear is used to estimeate the accuracy of the geostrophic momentum approximation by comparison of exact solutions when exist with approximate ones. 相似文献
955.
Dolmatova L.S. Eliseykina M.G. Timchenko N.F. Kovaleva A.L. Shitkova O.A. 《中国海洋湖沼学报》2003,21(4):293-304
Pure fraction (92% - 95%) of phagocytes (FP) and a mixture of amoebocytes (62%) and morula cells (38 % )-FPMC- of the holothurian Eupentacta fraudatrix ( Holothuroidea,Dendrochirota ) were obtained by using ficoll-verographine step gradient. Basal production of reactive oxygen species (ROS) in FP quantified by using reduction of nitroblue tetrazolium (NBT) was more than twice that in FPMC. Thermostable toxin of Yersinia pseudotuberculosis (TST) at differentconcentrations ( 0.2; 0.5; 2.5 μg/ml, but not 0.1 μg/ml) stimulated NBT reduction in FPMC after 24 h incubation. In FP, TST at concentrations of 0.1 and 0.2 μg/ml inhibited and at concentrations of 0.5 and 2.5 μg/ml stimulated NBT reduction after 24 h incubation. Maximal effect was observed in FP and FPMC at TST concentrations of 0.5 and 0.2 μg/ml, respectively. Addition of catalase (0.7 μg/ml) to the cells treated with TST (2.5 μg/ml) was followed by a decrease in NBT reduction compared to that under toxin treatment alone. TST stimulated superoxide dismutase activity in ccncentration-dependent manner (maximum at 0.5 μg/ml concentration in FP) after 24 htreatment, and this stimulation was prevented by a commercial catalase. Plant lectin concanavalin A stimulated NBT reduction more than 5-fold in FPMC compared to the control. With addition of TST, lectin stimulated ROS to lesser extent than that with lectin alone. When catalase, TST, and lectin were added into the FPMC simultaneously, ROS increase was similar to that under lectin treatment alone. On the whole, data obtained indicated that ROS generation in holothurian coelomocytes especially occurs in both stimulated and not stimulated phagocytes, and that changes in ROS production by these cells may be one of the mechanisms of antibacterial protection of holothurians. 相似文献
956.
Victor F S SIT 《中国地理科学(英文版)》2003,(4)
1 NEEDFORNEWCOMPETITIVENESSINTHEPEARLRIVERDELTAIn1978ChinaadoptedanewapproachofOpen andReforminitsdevelopment.Priortothis,HongKongwasaBritish-runenclaveoffreetrade,andwaslittlerelatedeconomicallywithitsnextdoorneighborandnaturalhinterland—thePearl(Zhujiang)RiverDelta(PRD)(SIT,1991).Sincethen,localinitiativesofGuangdongProvinceanditsconstituentmunicipalitieshaveprovidedanattractivemilieuforHongKongin-vestment.IthassoongrownintoHongKong'snewmanufacturingbasewhileHong… 相似文献
957.
J.CRAIG HAMILTON Shared Research Resource Laboratories School of Medicine East Carolina University Greenville NC U.S.A.PAUL J.GEMPERLINE Department of Chemistry East Carolina University Greenville NC U.S.A. 《地理学报(英文版)》1990,(1)
One of the major applications of factor analysis in the chemical literature,self-modeling curve resolution(SMCR),is covered in this review,including a historical account of the inethods derived from Lawtonand Sylvestre's original method.Papers treating the theory or applications of SMCR are included.Qualitative and quantitative applications are described where appropriate. 相似文献
958.
959.
A case study of the convectively driven monsoon boundary layer has been carried out using the aerological observations at four stations in the region of monsoon trough during Monsoon Trough Boundary Layer Experiment (MONTBLEX) 1988. The Convective Boundary Layer (CBL) in the region of monsoon trough did not show double mixing line structure. A single mixing line representing the CBL with different stabilities with respect to the convective activities was observed. 相似文献
960.
该书的作者们独辟蹊径地研究整个显生宙地层剖面,其目的是从这些剖面可能揭示出一系列地外成因的事件。暂且不论这费劲的工作收益有多大,一个引人深思的问题在于,象这样一本书在10年前能否被接受并出版?但正是在这10年间,许多地质学家已注意到:他们研究的课题同天文学和天体物理学有联系。1980年出现了观念性的变化,在这之前,任何一种把 相似文献