简介：从表达现实世界的方式和解决具体问题的方法这两方面出发，论述了GIS逻辑数据模型和物理数据模型的设计与表达。根据数据的使用方式决定地理数据模型的选取，以建立面向对象的地理要素模型为例来说明建模的过程，提高模型的实用性。

简介：专业地理信息系统中,不同用户角色拥有不同用户权限区,这种角色控制方式是适合现行的管理机制的,但该种方式以区域来确定用户权限区的固定角色控制在解决跨区域协作问题存在困难,当事务发展涉及到多个区域时,不能合理有效的信息共享,造成信息系统失效.针对该问题在基于角色的访问控制基础上,提出空间相关的动态角色控制,分析其需要考虑的各个方面,做了详细的设计,探讨了总体结构和核心设计.最后通过一个森林防火地理信息系统中火灾跨区域扑救协作典型实验,来验证空间相关的动态角色控制对解决跨区域协作是可行的.

简介：BasedonthebiologicalresourcessurveysinChina'sexclusiveeconomiczone,thepaperdiscussestheapplicationoftheGIStechnologyinevaluatingthemarineenvironmentalquality,establishesthebasicconceptandtechnologicalprocessforevaluatingtheenvironmentalqualityofthehabitatsofmarinelivingresources,proposesthekeypointsfortheestablishmentoftherelevantevaluationattributesdatabasebyapplyingtheGIStechnologyandanalysesseveraltypicalevaluationmodelsandthedatainterpolationmethodforthemodelinGIS.ResultsshowthatthecombinationoftheGIStechnologywiththequantitativeevaluationmodelcanbeappliedtothefastandaccurateevaluationofthemarineenvironmentalquality.

简介：TheprobabilityoffractaldeterminationofcoastaltypesbasedonGISispreliminarilydiscussedwithChinaasanexample.Finally,somesignificantconclusionsaredrawn:(1)Thefractaldimensionofcoastlineofthebedrockcoastislargerthanthatoftheplaincoastonthesamescalemap;(2)Asfarasthebedrockcoastisconcerned,thelargerfractaldimensionofcoastlineofthebedrockcoastonthesamescalemapindicatesthatthebedrockcoastisprobablynottypical;(3)Asfarastheplaincoastisconcerned,thesmallerfractaldimensionofcoastlineoftheplaincoastonthesamescalemapindicatesthatitisprobablythesiltplaincoast;(4)Thedifferentsubstantialcompositionsaffectthefractaldimensionsofcoastlinesofdifferentcoastaltypes.Ingeneral,thecoastwhichliesinthenorthoftheHangzhouBayconsistsofsandmainly,itssurfaceisflat,anditisconnectedwiththecoastalplain,itslandformisbroadshoal,itstotalchangeiscomparativelyhomogenousinthetidaldynamicprocess,andthus,therelativelysmallerfractaldimensionofcoastlineresultsfromthis.Forthebedrockcoast,thereismorebedrock,thecoastlineiscomparativelysmoothandstraight,beingaffectedbythefaultsandoceandynamicprocess,whichresultinthelargerfractaldimension.

简介：Theestuaryandcoastisanareawherethelandandtheseainteractandaplaceinwhichhumanbeingsfrequentlymoveaboutsothatunderstandingandcontrollingthechangeanddevelopmentmodesofthecoastallandformplaysavitalpartinexploitingandprotectingcoastalresources.Amodelisthegeneralizationandabstractionofobjectivethings.Thispapersummarizesfourmethodsforthelandformdevelopmentofthetidalshoreandunderwaterdelta,mainlydiscussesthemodel'sstructuralelements,andpresentstheirspecificapplicationonthebasisoftheauthors'casestudy.Withtheapplicationoftheprofilemodel,thedynamicchangeofcoastallandformcanbeclearlyseenbycontrastingthedifferentprofilesofdifferentyears.Throughtheshrinking,expandingandtransformationoftheisobath,planemodelisusedtostudythemacro-changeoftheshoalandthecoastallandform.Speedmodelisanefficientmeanstoanalyzethetrendoferosionanddepositionandthelocalchangeinagreatareaofthesea.Statisticalsurveymodelisastaticanalysis,whichcanbeusedtoestablishtherelationshipbetweentheerosionanddepositionoftheshoalandthealtitudeandslopeofsurveyspot.