The DEWS project has set itself challenging objectives to revolutionise the way in which users are able to work with high-volume, real-time environmental data and information. Web Services technology offers the only practical solution to developing a

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http//www.dews.org.uk/
The DEWS project has set itself challenging
objectives to revolutionise the way in which
users are able to work with high-volume,
real-time environmental data and information.
Web Services technology offers the only practical
solution to developing a Service Oriented
Architecture that can meet the requirements of
many environmental applications. The project is
examining scalability, interoperability and
interface with legacy systems and software,
reliability in an operational environment, the
security and auditability of specific
implementations. DEWS aims to demonstrate this
through two specific case study examples, in the
Marine Safety and Health sectors. These examples
are being used to show the powerful capabilities
that Web Services can offer, to examine the
benefits and shortfalls as they stand at present,
and importantly, to promote early adoption by
potential users of these technologies in an open
architecture/open source environment. In
addition the project also expects to deliver a
range of new open source tools, Web Coverage,
Feature and Map Services and OGC-compliant,
XML-based data standards.
The BMT Platform is a modular application suite
comprising three core modules SEAINFO
Responsible for retrieving and processing data
from the DEWS marine web coverage service. This
incorporates a NetCDF extractor applied to a
Postgres database. SARIS Responsible for
providing web processing services and web feature
services to the SARIS Clients SAR Clients
Remote Rich Client application which consumer
data from the SARIS system.
IBM Websphere Software IBM is providing industry
leading middleware software that has allowed the
team to build, deploy and run the DEWS technology
showcase demonstrator in a proven, secure and
flexible environment. Websphere enables users to
connect via Web services and to view DEWS
information sources from health and marine safety
IT systems where the data is held in secure, high
volume data base systems. Information is
presented through a single portal that is
personalised at the time of log on, presenting
content customised to the needs of the
individual.
WFS Health information is exposed via a web
feature service (WFS). The WFS exposes a OGC
standards-compliant interface allowing any WFS
client with appropriate privileges, such as the
DEWS Portal, to request information. The health
information exchanged between server and client
is encoded in a domain-specific 'Application
Schema' that leverages the GML standard. This
application schema forms an agreed 'contract' for
exchanging content within an 'information
community'. Geoserver's WFS implementation allows
data in a private datastore conforming to a
private 'persistence schema' to be mapped onto a
published application schema, thus enabling a
data provider to participate in an information
community without needing to re-engineer their
private datastores.
WCS GADS-WCS is the marine data server in the
DEWS system, serving gridded ocean analysis and
forecast data from the Met Office to BMT and
other clients. It is based upon the OGC Web
Coverage Service standard, with modifications for
large data volumes and security and the server
can be accessed at http//lovejoy.nerc-essc.ac.u
k8080/geoserver (see screenshot below)
Health Database The Health database contains the
'health forecast' data plus all the information
required by the Health application to create the
health forecast, including the real-time
statistics being supplied by healthcare
organisation and the Met Office's weather
forecast. Because the WFS enables the mapping of
the database schema onto a published application
schema, the health database is decoupled from
'upstream' applications ensuring that external
applications that rely on the health forecast
will not be impacted by any changes to the health
database.
Data Ingestor Health Ingestion utilities read
and convert data provided by GP Out of Hours, NHS
Direct, Ambulance Services and the Royal College
of General Practitioners. These are received as
formatted e-mail attachments, CSV files or XML
files. Data Ingestor Marine An ingestion
process is provided as part of the DEWS
application to facilitate the loading of NetCDF
file data into the system.  NetCDF files are
transferred from a local file system and stored
in binary large objects (blobs) in an Oracle
database.
The BADC has developed Utility Services which
provide support for low level functions
including The Security Service ensures that the
security policy as defined for a particular data
stream is enforced throughout the platform. The
security model is based on that of the NERC Data
Grid. The Access Logging services provides a fine
grained audit trail of all transactions that
occur in the platform

• Terms and definitions
• OGC Open Geospatial Consortium
• GML OGC Geography Markup Language, v3.00 (OGC
  03-023r4)
• UML Unified Modeling Language
• XML Extensible Markup Language
• WCS OGC Web Coverage Service
• WFS OGC Web Feature Service
• WMS OGC Web Map Service
• 4-D Four Dimensional (three space dimensions and
  time)
• References
• GeoServerhttp//docs.codehaus.org/display/GEOS/Mu
  ltidimensionalWCS
• NetCDF http//www.unidata.ucar.edu/software/netcd
  f/
• OGC WCS Standard http//www.opengeospatial.org/st
  andards/wcs
• OGC WFS Standard http//www.opengeospatial.org/st
  andards/wfs
• OGC WMS Standard http//www.opengeospatial.org/st
  andards/wms
• WebSphere http//www-306.ibm.com/software/websphe
  re/

External Data Feeds Depersonalised data from two
health service providers (GP Out-Of-Hours and NHS
Direct) are emailed daily to the system. The GP
OOH data is based on the doctors call records
whilst the NHS Direct data is based on the
information gathered during a telephone
consultation. They therefore necessarily contain
different types of data. In future it is hoped
that other sources of data such as GPs and
hospital admissions will be sent for inclusion.
In the marine stream, the UK Met Office provides
gridded forecast and analysis model fields. A
number of parameters are sent from both
atmospheric and oceanographic models.

• Marine Database The smart datastore consists of
  an Oracle data cartridge, which is used to extend
  the functionality of the Oracle 10g database
  server such that it is able to deal with 4-D
  Gridded datasets.  In particular it
• Introduces a database object type which mirrors
  the NetCDF file format
• Provides the means to efficiently query any
  metadata associated with the NetCDF database
  object types
• Provides the ability to manipulate and transform
  the database object by performing functions such
  as rotation and interpolation
• Provides an efficient mechanism to automatically
  load a NetCDF file and it's associated metadata.