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961.
962.
TENSORIAL RESOLUTION:A DIRECT TRILINEAR DECOMPOSITION   总被引:4,自引:0,他引:4  
Modern instrumentation in chemistry routinely generates two-dimensional(second-order)arrays of data.Considering that most analyses need to compare several samples,the analyst ends up with a three-dimensional(third-order)array which is difficult to visualize or interpret with the conventional statisticaltools.Some of these data arrays follow the so-called trilinear model,(?)These trilinear arrays of data are known to have unique factor analysis decompositions which correspondto the true physical factors that form the data,i.e.given the array (?),a unique solution can be found inmany cases for each order X,Y and Z.This is in contrast to the well-known second-order bilinear datafactor analysis,where the abstract solutions obtained are not unique and at best cannot be easilycompared with the underlying physical factors owing to a rotational ambiguity.Trilinear decompositions have had the disadvantage,however,that a non-linear optimization withmany parameters is necessary to reach a least-squares solution.This paper will introduce a method forreducing the problem to a rectangular generalized eigenvalue-eigenvector equation where the eigenbectorsare the contravariant form(pseudo-inverse)of the actual factors.It is shown that the method works wellwhen the factors are linearly independent in at least two orders(e.g.X_(jr),and Y_(jr) are full rank matrices).Finally,it is shown how trilinear decompositions relate to multicomponent calibration,curve resolutionand chemical analysis.  相似文献   
963.
引言《地理学进展》的创刊号于1969年出版,在刊物创刊21周年之际,有必要对其宗旨和目的再作一次评析。本文将考察进步的概念,让我们先从定义入手。地理科学的进步,常常被定义为地理学家使他们的研究领域变得更具可知性的能力。像所有社会学科一样,这里存在着下定义的问题。更具知识性和可知性是什么意思?另一个更重要的问题是谁来决定这种进步是什么?学术研究来源于商界和政府在安排研究项目方面起至关重要且举足轻重作用的大千世界中,有时用一般的方式,有时则用特殊的方式。  相似文献   
964.
A solution of the nonlinear problem for determining the wind velocity in frictionless atmosphere (the gradient wind) under given geopotential (pressure) field is proposed. The approach is analytical and is based on quadratic polynomial approximation of the geopotential field and linear approximation of the wind velocity field with respect to x and y, the coefficients of the expansions being functions of the time t. The derived system of ordinary nonlinear differential equations is analyzed as a dynamical system. Exact analytical solutions are found for some particular cases. Some of their properties bear a resemblance to those or really existing atmospheric vortices (cyclones and anticyclones).  相似文献   
965.
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   
966.
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   
967.
968.
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   
969.
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   
970.
1 NEEDFORNEWCOMPETITIVENESSINTHEPEARLRIVERDELTAIn1978ChinaadoptedanewapproachofOpen andReforminitsdevelopment.Priortothis,HongKongwasaBritish-runenclaveoffreetrade,andwaslittlerelatedeconomicallywithitsnextdoorneighborandnaturalhinterland—thePearl(Zhujiang)RiverDelta(PRD)(SIT,1991).Sincethen,localinitiativesofGuangdongProvinceanditsconstituentmunicipalitieshaveprovidedanattractivemilieuforHongKongin-vestment.IthassoongrownintoHongKong'snewmanufacturingbasewhileHong…  相似文献   
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