26883.基于javascript技術的webgis設計與實現(xiàn)(1)

1、大連理工大學碩士學位論文基于Javript技術的WebGIS設計與實現(xiàn)姓名：房體盈申請學位級別：碩士專業(yè)：計算機應用技術指導教師：唐達20081217大連理下大學碩士學位論文DesignandImplementationofWebGISBasedonJavaScriptAbstractTherapiddevelopmentoftheInternet，drivesquickupdateanddevelopmentofthecurrentG

2、IStechnology，andprovidesGISwithanewandeffectivegeographicinformationcarrierNevertheless，thefurtherdevelopmentofGISwillfacetheproblemsofheavyburdenofmassdataprocessingandthebottleneckofnetworktransmissionJavaScriptcanmake

3、avarietyoftasksbecompletedonlyontheclientwithouttheparticipationofnetworksandservers，anditsupportdistributedcomputingandprocessingSo，theapplicationofJavaScripttechnologyinWebGIS，greatlyreducesnetworktransmissionandburden

4、oftheserverInthissituation，alltheGISoperationsaredonelocally，theserveronlyprovidesGISdataservices，anditalsoonlyhaveaonetimedatatransmissionThethesisintroducestheWebGISstructure，developingmodelsandallkindsoftechnologytoim

5、plementWebGIS，scientificallyanalyzesthetraditionaldefectsofelectronicmapdevelopmentfromtheviewofarchitecture，anddesignsanewWebGISimplementationmodelbasedonJavaScriptInthethesis，itbuildsawholeWebGISanddesignsitsmodules，wh

6、ichincludeselectronicmapview，spatialmeasurementandspatiallayerdevelopmentOnthewayofgeographicmapsprovided，itisnotthetraditionalway，whichtheservergeneratesgridpicturefrommassvectormapandsendsittotheclient，butanewwaywhicht

7、heserverimmediatelysendmanypreparedslicepicturestotheclientOnthedisplayofthemap，itusesanewwaywhichclientpiecesanumberofslicepicturestogethertoshowtheview，insteadofawholemapshownOnthedevelopmentofthespatiallayer，usingAjax

8、developmentmodelandVML(TheVectorMarkupLanguage)，itdesignesastoragestructureofthespatiallayer，andsomeperformancemodelofspatiallayerAnditgivesaverygoodsolutionabouttheoverlaybetweenthegridpictureandvectormapBytheevidenceof