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Geographic Software Reviewed in this article:

APPLEPIPS

IBM EDUCATIONAL SOFTWARE SERIES: EARTH SCIENCE SERIES. Moisture in the Atmosphere, Hydrologic Cycle, Surface Water Ground Water

MINI-MAX

MULTIMAP. Barry R. Cohen. Planning Data Systems

WORLD GEOGRAPHY SERIES, U.S. GEOGRAPHY QUIZ, U.S. GEOGRAPHY ADVENTURE  相似文献   

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ABSTRACT To study the law of emergence and growth of coal-mining cities, analysing their particular contradictions and problems and determining the orientation of their in-dustrial development, so as to adapt to local conditions, is quite essential in promo-ting comprehensive utilization of the natural resources, planned and proportionate development of regional economy and systematical distribution of the cities.  相似文献   

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ABSTRACT To study the law of emergence and growth of coal-mining cities, analysing their particular contradictions and problems and determining the orientation of their in-dustrial development, so as to adapt to local conditions, is quite essential in promo-ting comprehensive utilization of the natural resources, planned and proportionate development of regional economy and systematical distribution of the cities.  相似文献   

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l.TheRapidEcono1ulcDevelopmentofCho1aSinceeconoAncreformandopen-doorpolicy,Cltinahasgrownrapidly.GDPinl993is3.4tilllesasmuChasti1atinl978.Annualgrowtlrateis9.2percent.li1ti1isresped,itisworthwniletostudyWhereChinaislocatedinti1eecononticltistoryoftheworld,andwhatthetrendofcurrentdeveoPmentwillChangeinto.Indevelopedcountriesofh1eWest,whentherateofecononhcdevelopmotwasthelligheSt,itwasnotltigherti1anthatofCltina'seconol11icdevelopmentafterreforl11andopen-doorpolicy.U.K.,forexample,Whichh…  相似文献   

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In many environmental applications,such as exposure assessment and risk modelling,the desiredestimate is a random variable computed as the product of three independently distributed randomvariables.These variables may not necessarily have the same mean and variance.The method for findingthe 100(1-α)% confidence interval for the mean of the product random variable has been proposed bysome practitioners as the product of the 100(1-α)% confidence interval of the three means.In this paperwe show that the distribution of the product of three independent normal random variables is not normal.We find the mean and variance of the product distribution.Further,we show that although the meanof the product is equal to the product of the means,the product of the three confidence intervals is nota good approximation of the confidence intervals for the mean of the product variable.The confidenceinterval of the mean of the product variable may be estimated by computer simulation.An algorithmfor estimating the confidence interval for the mean of the product random variable is given.The programimplementing this algorithm is given as an appendix.  相似文献   

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This work analyses a storm that occurred in the Canary Islands early in November 1826. Through a study based on historical climate data, some of the adverse effects of the storm are described and some of the possible causes are discussed. The main goal of this work is to establish an approximate reconstruction of this historical event which will allow us to compare it to a recent meteorological event that had a great impact on the archipelago: “Tropical Storm Delta”, in November 2005. Studying and reviewing the origin of the 1826 storm verifies the hypothesis that extremely violent perturbations have not only occurred in the Canaries on other occasions, but that these past events were also more intense and had more serious consequences than Delta. Therefore, the idea that other tropical perturbations have occurred in the region of the Canary Islands before Delta is presented.  相似文献   

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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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l.Intl.oducho1lCllilla'snewl)o1iaessincelO78I1avebrougl1tabotltsPeedydeveloIJl11e11tofruralil1(lustly.Tllefastgro\Vthofl-Llralil1dustry11otol1lyope11sal1ex```aytore3lizethenationalilldustrlnlizatlonofChlna,butalsogivesasevel'ecl1aIIel1getothetraclitio11al…  相似文献   

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《Urban geography》2013,34(4):345-361
This paper examines the gender ratios of the Statistical Metropolitan Areas (SMAs) of Bangladesh for the last intercensal period (1981-1991) and discusses the factors that are associated with the changing gender ratios of the SMAs. The latest population census of Bangladesh suggests that the gender ratios of its four SMAs decl ined markedly during the last decade. This decline is explained in terms of the decentralization of government administration, initiation of rural development programs, increased opportunities for over-seas employment, and openings of employment for rural women in the garment industries of the SMAs.  相似文献   

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1INTRODUCTION Studiesonheavymetalcontaminationinsedi mentshavealwaysbeenfocusedonthecoastalandin tertidalareas(Sivalingam,etal.,1980;Ismail,1993;Ismail,etal.,1993;IsmailandRosniza,1997;Yap,etal.,2002a,2002b).Theheavymet alconcentrationsfoundinthesediments…  相似文献   

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Data of the hydrolysis of adenosine 5'-triphosphate have been re-evaluated using a computer program thatnumerically integrates the differential rate equations within a routine that optimizes rate coefficients givena suitable model and concentration versus time data. The model is tested by calculation of Hamilton R-values, the Fisher F-statistic, a sensitivity analysis,the standard errors on the rate coefficients and by constructing contour maps of the objective functionversus two rate coefficients. An optimization using only phosphate concentration data cannot distinguish between a model in whichadenosine 5'-monophosphate is formed predominantly directly with a molecule of pyrophosphate, andone in which it is formed via adenosine 5'-diphosphate. A more accurate set of rate coefficients iscalculated from existing data and the relative importance of the two paths determined.  相似文献   

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Each eigenvector of the dispersion matrix[X]~T[X]was shown to be a partial predictor of the originaldata matrix [X],the sum of the predictions from the individual principal components being equal to theexpectance of [X].By comparing the distributions of the members of two neighbouring predictedmatrices,[X]_(1...i)and [X](1...i+1)(i.e.the sums of the first i and i+1 individual predictions respectively),it was shown that they should be indistinguishable provided that i is equal to or greater than the effectiverank of [X],and significantly different otherwise.This was confirmed by analysing the visible absorptionspectra of methyl orange and methyl red solutions as well as the Raman spectra of Na_2SO_4 and MgSO_4solutions.On the grounds of these findings,a non-parametric goodness-of-fit test for assessing theeffective rank of[X]was proposed which proved to be comparatively conservative and more robust thanmost currently used tests.  相似文献   

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Statistical analysis of a multi-centennial dendrochronological proxy dataset of regional climate, constructed across the latitudinal gradient of 1000 km, was performed. It was shown that centennial ( c. 100 year), tri-decadal (27-32 year), bi-decadal (17-23 year) and decadal (9-13 year) periodicities governed the climate variability in Finland over the last five centuries. Despite the fact that many of the climatic periodicities bore great resemblance to periodicities of solar cycles, little evidence of actual solar influence on Finnish climate was found when the climate proxy records were subjected to linear correlation analysis with sunspot numbers. Highly non-linear response of Northern Fennoscandian climate to solar forcing might be a cause of this result, as well as influence of terrestrial climatic processes (e.g. effect of other forcing factors and internal dynamics of regional climate). Our results show that the presence of internal climate variability at time-scales of solar activity might distort the solar signature in climatic data and complicate its detection.  相似文献   

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