In the HydroShare information model, we separate the scienc - PowerPoint Presentation

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In the HydroShare information model, we separate the science metadata attributes into two types: generic metadata and class specific metadata. The generic metadata attributes are applied for all the data classes, and we propose to adopt Dublin Core Metadata Elements with additional sub elements to better elaborate them (Table 1). The class specific metadata attributes are to capture the class specific features. We examined the features of each data class and referred to some existing metadata designs for these data classes to select the attributes of the information model (Table 2 to Table 4). The science metadata attributes were selected to support the following purposes:

Providing information to facilitate data reuse Cataloguing to support data discovery using the system search functionalityVisualization functionality

Information Model

OCI-1148453

OCI-1148090

Representing

Gridded

and

Space-time

Data in HydroShare

Tian Gan, David G. Tarboton, Jeffery S. HorsburghCivil and Environmental Engineering Department, Utah State University

Table 1 Generic Metadata for All

Data Types

AttributesDescriptionAttributesDescriptionCreatorInformation about the person who uploaded the data created the HydroShare resource.DescriptionAbstract of the resource. nameName of creator.IdentifierThis is the system assigned Identifier for the corresponding resource. emailEmail of creator. internal IDInternal identifier of the resource. Assigned when the resource is first created. organizationOrganization of creator. external IDDOI of the resource. Only be assigned when the resource is published. mail addressMail address of the creator.TypeHydroShare system supported resource types. phonePhone of creator.FormatHydroShare system supported file format for a certain resource type. ContributorInformation about a person who contributed to the data.LanguageMajor language used in the resource . HydroShare will use the three-letter language codes defined by ISO 639-2. nameName of contributor.PublisherThe URL of the homepage for HydroShare system. contributionDescription of the contribution the person has made.SourceOther resources in or outside of the HydroShare system that derives this resource. emailEmail of contributor. nameName of the source. organizationOrganization of contributor. identifierIdentifier of the source. mail addressMail address of the contributor.RelationOther resources in or outside of the HydroShare system that is referenced by this resource. phonePhone of contributor. nameName of the referenced resource.TitleA name given to the resource. identifierIdentifier of the referenced resource.SubjectThe keywords for the resource. RightsInformation about rights held in and over the resource. HydroShare will encode a text statement or URL that points to a rights management or usage statement for the resource in the rights element. DateA point of time associated with an event in the lifecycle of the resource.CoverageTemporal and spatial information related to the resource. date createdDate when the resource is created. spatialSpatial information related to the resource. HydroShare system will specify it using DCMI Point or Box. date last modified Date when the resource is last modified before it is published. temporal Temporal information related to the resource. HydroShare system will specify it using DCMI Period. date publishedDate when this resource is published. CitationCitation information of the resource. (Not Dublin Core Elements)

Table 2 Key Class Specific Metadata for Time SeriesAttributesDefinition Variable NameName of the variable of the time series data. Variable UnitsName of the variable units of the time series data. Value TypeValue type of the time series data. e.g. “Field Observation”Data TypeData type of the time series data. e.g. “ Instantaneous”No Data ValueThe numeric data used for representing no data condition. Method Method used to get the time series data. Value CountNumber of values from the time series data.Data QualityData quality of the time series data. e.g. “Raw Data”Sample MediumMedium for collecting the time series data. e.g. “Water Surface”.Site NameName of the site for collecting the time series data.Site CodeCode of the site for collecting the time series data.Time SupportNumerical value and corresponding units that indicates the time support (or temporal footprint) of the data values. If time series is instantaneous data, it will be 0.**Full metadata details are under development drawing upon content of ODM/WaterML

Table4 Key Class Specific Metadata for Multidimensional Space-Time ArraysAttributesDefinition ConventionThe conventions used for the NetCDF file. VariableVariable stored in the NetCDF which doesn’t represent temporal and spatial coordinates. defined nameVariable name defined in the NetCDF. This name may not explicitly explain what variable it actually represents. full nameFull name of the variable. Explicitly explains the meaning of the variable. unitsUnits of the variable. data typeName of the data types. This has predefined vocabulary which is from the data types of NetCDF enhanced data model. dimensionsThe defined variable shape in the NetCDF. methodDescription of the method how the value of the variable is obtained. missing valueThe numeric data used for representing no data condition. associated groupThe name of the group which the variable belongs to.**Full metadata details are under development drawing upon information from NetCDF with CF conventions.

Table3 Key Class Specific Metadata for Geographic RasterAttributesDefinition Row NumberTotal row number of the raster datasets. Column NumberTotal column number of the raster datasets.Cell Size ValueNumerical value for the size of each pixel in the raster datasets.Cell Size Units Units for the size of each pixel in the raster datasets.Cell value typeThe data type for each pixel in the raster datasets. e.g. “Floating Point”.BandThe band information in the raster datasets. band nameThe name of the band. associated variable The variable name of the value in the pixel of the band. variable unitsThe variable units of the value in the pixel of the band. methodThe method used to get the value in the band. commentsFree text comments for the band. Any information useful for data reuse.**Full metadata details are under development drawing upon information from systems like GDAL and GeoTIFF, etc.

Share and Publish Data

In “Resource Detail” page, click on

“Setting” to share or publish the uploaded data.

User can set the access policy for data and metadata separately.

User can set “Share List” to assign the other users to share the data with.

Resources can be submitted for formal publication which upon acceptance will result in a DOI being assigned and the resource becoming immutable with open

metadata to public.

CUAHSI

HydroShare is being built as a web system for hydrologic data and model sharing. It will expand the data sharing capability of the CUAHSI Hydrologic Information System (HIS) by broadening the classes of data and taking advantages of social media functionality to enhance the collaboration around hydrologic research. One aspect of the HydroShare development is to design the information

model

to capture the science metadata information for each data

class. It will

be

used for

cataloging purposes, facilitating data reuse and supporting some system front end functionality. We present the design of the information model for the gridded and space-time data classes which include time series, geographic raster and multidimensional space time arrays, and story board the proposed system functionality for creating, visualizing, sharing and publishing the three data classes to offer a suggested vision for how gridded and space-time data may be represented in HydroShare.

Introduction

We present the aspects of the HydroShare of information model and system functionality for data creation, visualization, sharing and publication, so as to provide a suggested way representing gridded and space-time data in the HydroShare system. The information model is important, as it serves as a foundation for the representation of content in HydroShare and can help to better support reuse of the uploaded data and some of the system front end functionality. For the information model design, we propose to separate the science metadata attributes in two types which include the generic metadata applied for all the data classes and the class specific metadata to capture the class specific features. The proposed system functionality aim to provide user with useful information about the data and the ability to interact with other data available in the system.In the future, we will refine the information model and try to implement some suggested system functionality. Besides, we will design the social metadata and the system metadata attributes to better manage the uploaded data and the involved social information in HydroShare system.

Currently, we set up the HydroShare Beta Website. If interested, please visit:http://dev.hydroshare.org/If any suggestions for design of information model or the system functionality, please email to:David G. Tarboton: dtarb@usu.eduJeffery S. Horsburgh: jeff.horsburgh@usu.eduTian Gan: gantian127@gmail.com

Conclusions

Further Information

Visualize Data

Time series visualization will show some class specific metadata and the site location in the map. In the visualization tool, it has the function to add other time series data listed in the Resource Table.

The Raster visualization tool will provide the view function similar as ArcGIS. Besides, it can also add the feature class and the time series which are listed in the Resource Table. The time series will be represented as point.

The NetCDF will also be visualized in the same tool for raster data. It can generate the animation of the data changing with time. And user can use the “Identify” tool to visualize the time series for a selected cell.

In “Resource Detail / General Info” page, click on “Visualize” to see graphics of data. This page also shows some generic metadata information, the comments of the data and the editing history.

Create Data

Resource Table contains all the data uploaded by or shared with the user in HydroShare system.

“Create”

button is the start of creating a resource in the system.

When

data files are

uploaded, system will

automatically populate

some of the science metadata attributes by referencing system information or by extracting the information from

data

files

.

System will create a resource as long as a data file is uploaded into the system. And user can complete the science metadata, add or delete data files anytime later.

The second step is to upload data files. User

can drag

files or folders directly to this interface or browse to select files.