Addressing the Need for Bathymetric Data Management.pdf - Caris

(Above) A simplified representation of thefile-based workflow for the bathymetricdata management.(Right) Bathy DataBASE and HPD workflow.Bathy DataBASE SolutionBathy DataBASE is a software suitecomposed of a client application,database server and database administrationtools. The processing toolsavailable in the client application canalso be accessed as a standalonedesktop application.Workflow. An intrinsic part of theBathy DataBASE system is the flexibletool set provided to evaluate and editdata sets from third-party sources,preparing the data to meet the standardsof an organization so they canbe used to enhance the organization’sdata holdings and coverage. All validdata can potentially be used in thecreation of products such as nauticalcharts.A typical chart production workflowwould have data coming into thesystem from various sources, withsome data preparation and validationtaking place using the tools in BASEManager. Validated data and metadatawould be loaded into the BathyDataBASE server. Measurements suchas soundings, contours and depthareas would be generated from thesource data.Database Architecture. The BathyDataBASE system is based on a clientserverdesign. The system supports thestorage and management of bathymetricdata in the BASE Surfaces,bathymetric attributed grid files andsounding set formats.Data are loaded into the BathyDataBASE server as survey and sur-face objects. Each surveyand surface object hasassociated metadata basedon S-57 attribution—the standardused for the exchange of digitalhydrographic data between nationalhydrographic agencies and for distributionto stakeholders. The catalogsdefining the objects and their attributesare in extensible markup languageformat and are customizable by theuser.The object metadata and systemgeneratedbounding polygon coordinatesare stored in the database. Theserver software manages all interactionsbetween the client applicationand the objects in the database. Ithandles transactions requested by theclient application (the primary clientbeing BASE Manager) for data loading,data extraction and object editing.Server resources are also used inthe creation of generalized and deconflictedsurfaces and the generationof bathymetric products(i.e., contours) from sources inthe database.The objects resulting from thede-confliction process are also storedin the database. Both the resultingsurface and the supersede decisionsdefined for the de-confliction aremaintained, the surface is stored as asurface object and the supersededecisions are stored in a product profileobject. The product profile objectcarries information about the areathat has been superseded and theparameters of the supersede decision.The Bathy DataBASE solution wasdesigned to be scalable in terms ofaccommodating the types and volumeof data currently being surveyedwith multibeam and lidar systems.The scalability also addresses theneed for coverage on a global scale asneeded by some organizations thathave a mandate beyond sovereignwaters.

“The logical extension of any data managementsystem is the distribution of those resources toclients.”Distribution. The logical extensionof any data management system is thedistribution of those resources toclients. Due to the massive improvementsin communication systemsover the past several years, deliveryvia the Web has become an efficientmechanism for disseminating geospatialinformation.The CARIS solution for spatial datadistribution on the Web is SpatialFusion Enterprise. This technologyprovides an interface to spatial data,including hydrographic informationand bathymetric data. Via the Webinterface, the user has the ability toview, query and select data sources.Spatial Fusion Enterprise implementsthe Open Geospatial ConsortiumInc. ®(Wayland, Massachusetts)specifications for Web map service.This allows data to be easily sharedamong organizations and allows connectionsto external Web sites forviewing additional sources of data.Pilot Project: CHS Quebec RegionAs part of a larger initiative to adoptdatabase-driven technology in theprocessing and management ofbathymetry and hydrographic data,CHS’s Quebec, Canada, region isevaluating Bathy DataBASE.The CHS Quebec region is in theearly stages of evaluating Bathy Data-BASE to improve the management ofthe bathymetry results from varioustypes of surveys. Sources of bathymetryinclude new and historical singlebeam,MBES, lead line and other systems.CHS has a mandate to manageall bathymetry sources for Canadaand to provide these data to itsclients. The goal of investigating newways of managing these data is to beable to respond in the most efficientway to all requests from its clients.Using a bathymetry data managementsystem like Bathy DataBASEallows bathymetry extracts to be tailoredto meet a specific set of criteria.The criteria may include specificationsfor epoch, resolution and attribution.The data are provided to awide variety of clients for applicationsin navigation, science and engineering.File-Based Workflow. The currentpractice in place for the managementof bathymetric data is the use of NTXfiles—CARIS exchange format files.All data are converted to a commondatum and cartographic projection tomake the future analysis easier. In thecase of multibeam data, there is anextra step in the process. The originalfile is decimated to a sounding densitythat makes the files usable withoutlosing too much detail. After the conversionto a common format, analysisis done by comparison to files thatcover the same area. A decision ismade to modify the status (suppressedor not suppressed) of data if achange is required.Once this analysis is complete, thenew file is accessible to other users.All the steps need to be recordedmanually in the CHS metadata database(CHSDir) for tracking. To accessthe data, the user needs to utilizeCHSDir to make a query on theattribute that they are looking for(type of survey, geographic query,etc.). Even if only a small area of alarge file is needed, the entire fileneeds to be imported. The user needsto manipulate the files to access thearea of interest.Interaction with CHSDir makes themanagement complex and restrictivein terms of access and distribution toall clients. The file management isrestricted in the interaction by thedatabase, which provides only onewaycommunication.Bathy DataBASE Workflow. Thegoal of this pilot project is to explorethe possibilities offered in the newCARIS technology to complete theping-to-chart workflow in a productionenvironment. CHS would like toimprove its bathymetric data managementby developing interaction withits internal databases (two-way communication)and improving accessibilityto the community.A bathymetric data managementsolution must have some basic qualitiesin order to fit into the CHS work-flow process: interaction with existingdatabases (CHSDir, CARIS HPD),seamless integration with the technologiesused in adjacent processes(upstream [host-based intrusion-preventionsystem] and downstream[HPD]), datum adjustment (management),minimal loss of information (asclose as possible to the source), traceabilityof data from source to product,easy access to the data for internaland external users (Web access), performanceand robustness of the applicationand evaluation of the exportformats by the clients.Investigation of Bathy DataBASE.The effective management of bathymetricdata is crucial to CHS. Thedevelopment of new tools and datamanagement solutions allows CHS toexplore new opportunities to upgradeor adjust workflow practices.Two principles exist for the managementof data: load data as a navigationsurface (BASE Surface) or apoint stored file (sounding set). CHStested both possibilities to evaluatewhich of those two would bestaddress its needs.The area coverage selected for thetests was limited to Quebec Harbor,which contains around 50 sourcedocuments, from lead line to multibeamdata. Before loading both testdatabases, all files were converted toa common datum and coordinatesystem.Historical sparse data were convertedto a sounding set and BASESurface format. Data with enoughsounding density were converteddirectly to BASE Surfaces. After theconversion, a survey was created foreach of the files, and metadata wereadded manually using informationcontained in CHSDir.The data were loaded into the databaseattached to the previouslydefined survey. Once the data werecompletely loaded into both databases,testing began on the supersedingrules at the extraction.While access to the data provedefficient and easy, initial tests did notgive the anticipated results. CHS hadexpected that conflicts would besolved at a data-set level instead of atthe node level. Further review of theresults now must be completed inorder to determine if the old methodsare still valid or necessary. Discussionwith other CHS regions or even other