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1.
TheNanshalslandsarethesouthetnmostterritoriesinChina.TheIslandsconsistof230islands,redandbeaches.Inthehistoricalperiod,theChineseancestorsovercamedifficutiesandfOundtheIslands2,0OOyearsago.Agreatmanyofhistoricalliteraturesindicatethatheeariiestrecords,mpa…  相似文献   

2.
《极地研究》1991,2(1):46-52
EISCAT (the Incoherent System at the northern polar region) data are used in discussion of the magnetosphere-ionosphere coupling. Comperison between samples in geomagnetic quiet days and during magnetic storms shows a significant effect of the basic magnetospheric processes on the features of the polar ionosphere. It not only demonstrates that the polar ionosphere can be regarded as a 'panoramic screen' of these process, but also indicates an importance of the simultaneous observation of southern and northern polar regions (especially, at the magnetic conjugate points). A few topics concerned are suggested for the further study of the southern polar region.  相似文献   

3.
TheYarlungZangboRiverCanyon,whichencompassesMountNamjagbarwa,isoneofthefewmysticalforbbidenareasremainingonearthandishometomanyprofoundgeologicalandbiologicalmysteriesawaitingexploration.Inrecentyears,scientistsfromtheInstituteofGeographyandInstituteof…  相似文献   

4.
Over the past 15 years the linear learning machine has been applied to a large number of chemicalproblems.The learning machine approach is conceptually simple and does not require knowledge aboutthe statistical distribution of the data.However,there are problems associated with this approach.Oneproblem which has not been investigated is the influence of mislabeled samples on the positioning of thehyerplane in feature space.If a few samples in a data set are incorrectly tagged prior to training(i.e.thesamples are labeled as members of class 2 even though they are actually members of class 1),it is stilIpossible using the linear learning machine to achieve a classification success rate of 100% for the trainingset.However,unfavorable results will be obtained for the prediction set.The magnitude of this effect andits potential implications regarding the proper use of the linear learning machine are discussed.  相似文献   

5.
I.IntroductionWeatheringbehaviourofrockmustbeviewedasbeingtheresultofinteractionbetweentheintrinsicpropertiesandexternalclimaticconditions[45].Mostreferencestofrostshatteringhaveemphasisedthedisruptiveforcesassociatedwiththephasechangesofwatertoice[1,26,34,3…  相似文献   

6.
LTkemskS0tu.ce0fL0ng-mstance0nflpeAncEwiceringSincel992,thenskassessmentoflongdistanceoilpipeline(LDOP)inN0rthwestChinahasbeenputtoagendasystematically.TheLD0PconstruCtionfromLiuyUantowntoLu0yangcltymakeuPthemajorpipelineengineeringwhichstrotchesover2,ll5kmandservesasoneofthemaJorcrudeoilpipelinesinnorthWestinlandroponofChina(Figurel).Theriskeventinducedbynaturaldisasterscanbedividedintofourwaysfl.EaffoquakcIhhistory,LD0PenrouteroponsexPenontaleafthquakes.Theearthquakemagntude,scal…  相似文献   

7.
8.
SYNOPSIS For the sake of flood and sedimentation control down-stream of the reservoirs, a study has been carried out on the ways of operation of several reservoirs in the Lower Yellow River. A program on the regulation of flow and sediment is suggested with the following purposes:  相似文献   

9.
Sincel986,theIntngatedSurveyTeamtotheNanshaIslandsorgn1lizedbytheChineseAcademyofScienceshasbeenengnginginthesystematicsurveyandstudyongeophysics,marineenvironment,livingthingr,contnbutingfaCtorsoftheislandsandtheltistoricaldevelopmenintheNanshaIslandsand…  相似文献   

10.
ABSTRACT According to repeated measurements at the fixed station, geomorphological in-vestigation, documentary records and recalls of the local residents, the Batura Glacier's terminus has undergone many changes during the- Quaternary and recent time.  相似文献   

11.
ABSTRACT According to repeated measurements at the fixed station, geomorphological in-vestigation, documentary records and recalls of the local residents, the Batura Glacier's terminus has undergone many changes during the- Quaternary and recent time.  相似文献   

12.
SYNOPSIS For the sake of flood and sedimentation control down-stream of the reservoirs, a study has been carried out on the ways of operation of several reservoirs in the Lower Yellow River. A program on the regulation of flow and sediment is suggested with the following purposes:  相似文献   

13.
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   

14.
Mountain research is a comprehensive work. Its main contents are:1. the theory and the method of mountain rescarch;2. the comprehensive development. utilization and protection ofmountain resources:3. mountain calamities and their prevention and control:  相似文献   

15.
I.Introductionl.BasicfcatUresofportcitiesandthcirwhuencingfactorsTl1elhstoricalexperiencesofdevelopedcowtrieshavewitnessedtheessel1tialro1eplayedbyseaportsinpromotingdevelopn1entofnationaleconomy.Manyportcities,emergodfron1marinetransportation,supportedbyseaandlandroLrtesandflourishedn1ainlythroughindustryandtrade,oftenbecomendonalornationalecononhccenters.fu11ongti1eworld's2Omeqalopolesofmorethan6ntilIionpopulation,l2areportcities.AlmosteverycoUntrywiti1coastalline,longorshort,roprdsoneors…  相似文献   

16.
The effect of peak shifts on the performance of a Kalman filter multicomponent analysis algorithm hasbeen investigated.A series of Gaussian test systems were employed to characterize the concentrationestimation errors and the morphology of the on-line residuals(the innovations sequence).Both forwardand reverse filters were used in the generation of the innovations sequences.It was found that thedifference between the forward and reverse innovations sequences gave an accurate indication of thedirection and magnitude of the peak shift.A series of overlapped two-component systems were alsoinvestigated.Again,a correlation between the difference innovations and the degree of the responseshift was observed.The behavior of the Katman filter in fitting the shifted fluorescence emissionspectrum of benzo[a]pyrene was also examined.The response for henzo[a]pyrene in cyclohexanesolution was compared to that obtained on the surface of a reversed phase thin layer chromatographyplate.A red shift of 4 nm was detected for the surface spectrum by observing the difference innovationssequence.This approach holds promise for correction of response shifts in multicomponent systems.  相似文献   

17.
1.1ntroductionVolcanosofMt.Unzen-dakeinJapanandMt.PinatubointhePhilippineseruptedoneafteranotherduringthefirstandsecondtendaysOfJunel99l.ThevolcaniceruPtionindex(VEI)ofMt.Pinatub0withgrade6isthehighestoneinthesCenury[2].Inl99l,rainyseasonadvantalintheYang…  相似文献   

18.
19.
《极地研究》1992,3(2):56-68
The extension of ice sheet on King George Island during the last glaciation was an environment event since the last glaciation. At that time South Shedlands Islands were a large unified island and the ice mass on King George Island might come from the Antarctic Peninsula. The model of ice retreat and ice advance events in the Holocene show that the ice sheet was separated into three small ice caps and then dispeared gradually. At present the retreating velocity of glacier is about 1.3m each year. After the retreat of ice sheet the isostatic compensation appeared in the crust there, and then 5-6 steps of the uplifted marine terraces have been developed along the coast. The uplift rate of the crust may be 6-10mm/a.  相似文献   

20.
Atpresent,theMiddleEastisaregionoverwhichmanykindsofcontradictionsexist.Itisobviousthattherootcauseliesinitsimportanceinthestrategicgeographicalpositionandrichresourcesofoilandnaturalgas.Ithasalwaysbeenahotspotintheworld,andconflictshaveoccurredthereco…  相似文献   

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