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This tutorial paper presents a simplified view of one of the more recently published multivariatecalibration methods particularly suited to dealing with non-linear data sets.The method is referred toas MARS and stands for multivariate adaptive regression splines.Simple examples are provided toexplain the workings of the method. 相似文献
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S.TING.Ph.D. 《地理学报》1944,(0)
The Association of American Geographers organized under Engeln, a symposium on the general subject of Penck's contribution to geomorphology and its relation to the .Davisian system. The published Annual of Dec. 1940 devoted .wholly to this subject reached me through Prof. Cressey four years later. It seems to me, being a 相似文献
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PHILIP K.HOPKE 《地理学报(英文版)》1992,(2)
In many cases,monitoring data for ambient airborne particles can be organized in the form of a three-way data table with one way for chemical species,one for sampling periods and one for sites.A directtrilinear decomposition followed by a matrix reconstruction(DTDMR)is developed to analyze such adata table as a whole.The three-way data set is composed into three two-way matrices by a direct trilineardecomposition(DTD).The column vectors of each of the matrices are called‘source profiles’,‘emissionpatterns’and‘site coefficients’respectively.Particulate sources are identified by examining both theirsource profiles and emission patterns.After the sources have been identified,emission patterns and sitecoefficients are used to produce a three-way matrix that gives estimates of mass contributions of sourcesto the samples collected at every site in every period.By simulation study,not only has the method beenverified,but a good indicator has been found that shows the number of factors(i.e.sources)in thesystem.Unlike other receptor models,DTDMR does not require source profile data and does not involvetrial-and-error procedures.Since DTDMR identifies sources based on variations in two dimensions,it hasa higher potential to distinguish two sources that have similar chemical compositions.The DTDMRmodel has provided excellent results with simulated data and has been applied in a real world three-waydata set. 相似文献
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TENSORIAL RESOLUTION:A DIRECT TRILINEAR DECOMPOSITION 总被引:4,自引:0,他引:4
EUGENIO SANCHEZ~ BRUCE R.KOWALSKI Laboratory for Chemometrics Department of Chemistry BG-.University of Washington Seattle WA U.S.A. Mobil Research Development Corporation Paulsboro Research Laboratory Billinsport Ro Paulsboro NJ U.S.A. 《地理学报(英文版)》1990,(1)
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
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Rex J. Rowley 《The Professional geographer》2013,65(1):155-157
Books Reviewed: Browning, Frank A Queer Geography: Journeys Toward a Sexual Self Fellows, Will Farm Boys: Lives of Gay Men from the Rural Midwest Rubenstein, James M. The Cultural Landscape: An Introduction to Human Geography. 6th ed Knox, Paul L. and Marston, Sallie A. Human Geography: Places and Regions in Global Context Kuby, Michael; Harner, John, and Gover, Patricia Human Geography in Action 相似文献
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Sanjukta Mukherjee 《The Professional geographer》2013,65(4):621-622
Entering overseas markets provides challenges for firms, especially for those with little international experience. These obstacles can be compounded for manufacturers of advanced machinery, as previous research suggests that a physical presence is necessary for the successful implementation of their products in export markets. One way for producers to address this issue is to participate in trade fairs, which enables a physical presence of staff and machinery to be established. Evidence from a survey of Korean machinery producers at a recent trade fair suggests that a physical presence is related to the importance that firms ascribe to exports and to the role of trade fairs in new sales. 相似文献
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Colllin Lee 《地理学报(英文版)》1996,(2)
I.IntroductionTheuseofquantitative111odeIstodevelopUnderstanding,prePareforecastsandexplorepolicyoptionsinthecontextofurbanandroponaldevelpl11entremainsapopularaCtivlty,althouglrathermoresointheacadel11iccol11n1unitythanintl1epIanningprofession.However,thehistoryoftheapplicationoffon11aln1odelstopolicyproblemsdoesnotproducegreatconfidence.objeCtiveevaluationoftheuseofl11odelsinpolicyn1akingiscomplicatedbythefaCtthat,asafonl1ercolleagueoncesaid,con1puter111odeIsarelikecl1ildrenfmostpeopleten… 相似文献
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《The Professional geographer》2013,65(2):124-129
Abstract This study examines the role of surface geomorphic features in tree establishment at the alpine treeline in Glacier National Park, Montana, through the presentation of a multiscale, conceptual model of biogeomorphic relationships at alpine treeline. Empirical observations gathered through a multiscale field methodology over three summers serve as a base for the model. The model highlights the importance of surface geomorphic features, specifically boulders and terrace risers, in creating favorable local site conditions, largely by protecting seedlings from wind. The sheltering effect of surface features enables initial seedling establishment, and in some cases survival, above current treeline locations, thereby initiating a positive feedback effect that encourages subsequent tree establishment. Geomorphic features are therefore important in linking scales of pattern and process at the alpine treeline ecotone. 相似文献
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《地理学报(英文版)》1948,(1)
Although records on the Yellow River are voluminous, they are often overburdened with great engineering details and scattered in a large number of technical journals and publications as to be not readily available to geographical students.“A Symposium on the Yellow River”. 相似文献
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PAUL W. BLANK 《Geographical review》1999,89(2):265-277
ABSTRACT. This article examines the parallels between the developing Pacific Basin and the historical Mediterranean Basin. Humankind's expanding reach in transportation and communication technologies now makes it possible to integrate a basin the size of the Pacific. The Mediterranean provides some insight into the processes involved. Topics include questions of hegemony, “mirror cities” that interact with each other across the basins, and the dynamic tension between cosmopolitanism and localism. 相似文献
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Samuel M. Otterstrom 《The Professional geographer》2013,65(1):147-149
Ryan, James R. Picturing Empire: Photography and theVisualization of the British Empire Sizoo, Edith (ed.) Women's Lifeworlds: Women's Narratives on Shaping their Realities. Teaford, Jon Post-Suburbia Government and Politics in the Edge Cities. Warhus, Mark Another America: Native American Maps and the Historyof Our Land Yeung, Y. M. and Chu, David K. Y. (eds.) Guangdong: Survey of aProvince Undergoing Rapid Change Young, E. M. World Hunger 相似文献
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Dallen J. Timothy 《The Professional geographer》2013,65(1):157-158
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Wang Xuejun Department of Urban Environmental Sciences Peking University Beijing People''s Republic of China 《地理学报(英文版)》1997,(1)
I.IntroductionUsingcomputertomakestatisticalcharthascurrentlybecomeverypopular(LiandZhang,1981),butinmanysocialandeconomicactivitiessuchasnationaleconomicmanagementanddecisionmaking,aconsiderablepartofstatisticaldataiscollectedwithinacertainadministrative… 相似文献
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Michael Farrell 《The Professional geographer》2013,65(1):126-128
The purpose of this study is to answer several important questions concerning the learning of categories of geographic information from maps. Categorization is a fundamental part of both learning and communication, and learning and communication are, in turn, central to any field of study. If categorization is a fundamental part of the learning process, then how people categorize information learned from maps must be of concern to cartographers and geographers. This study examines map reader categorization by having subjects in an experimental situation learn categories of maps. The primary variables in this study are the coherence of the categories and the duration of exposure to the categories. It was found that coherent categories cause subjects to rely on prior knowledge. The ability to use prior knowledge allows subjects to learn categories quickly, but it also causes them to make inaccurate assumptions about the category membership. This finding was not altered when subjects were given longer exposures to the category membership. 相似文献