Global Drought Monitoring Service through the GEOSS Architecture ...
Global Drought Monitoring Service through the GEOSS Architecture ...
Global Drought Monitoring Service through the GEOSS Architecture ...
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Architectural Implementation Pilot, Phase 3 Version: 2.0<br />
<strong>Global</strong> <strong>Drought</strong> <strong>Monitoring</strong> and European <strong>Drought</strong><br />
Observatory-Water SBA Engineering Report<br />
Date: 11/Feb/2011<br />
<strong>Architecture</strong> (Nagai 2010)<br />
Figure 13 (Nagai 2010)<br />
3.4.1 Adding Advanced Search and Discovery using Semantics<br />
The AIP-3 video 23 , “<strong>Drought</strong>—European” includes a walk<strong>through</strong> demonstrations, in<br />
which users select scientific terms (or “concepts”) and, secondly, <strong>the</strong> geographic region or spatial<br />
domain which is defined within a bounding box. This reflects <strong>the</strong> division into lexicographic and<br />
geographic content which has been cited in Section 3.5. The purpose of <strong>the</strong> semantic enrichment<br />
was to supplement keyword searches, such as used on Google, by adding search capability that<br />
could search <strong>through</strong> concepts; this is tantamount to adding “Semantics.” In o<strong>the</strong>r words, one is<br />
not searching for “drought” as a keyword; one is searching for “drought” as a concept, combined<br />
with search functionality that allows <strong>the</strong> user to select broader or narrower searches within <strong>the</strong><br />
drought field or within allied fields. For example, “water” is a concept which can be broken up<br />
into underlying processes of “evapotranspiration,” “streamflow,” “precipitation,” “soil<br />
moisture,” “snow cover,” and “groundwater.” The stores of water are a subset or part of water,<br />
and this class structure is affected in <strong>the</strong> arrangement of <strong>the</strong> terms within <strong>the</strong> semantic network.<br />
Datasets can be registered to each of <strong>the</strong>se terms, so that queries of “hydrologic drought<br />
indicators” reveal “groundwater” data, “streamflow” data, such as baseflow, and o<strong>the</strong>r water<br />
budget information for a selected area. The Euro<strong>GEOSS</strong> discovery broker has <strong>the</strong> capability to<br />
access <strong>the</strong> GI-Cat registered datasets on groundwater, river discharge, water usage, and o<strong>the</strong>r<br />
data. Search-by-concept is intended to not only improve <strong>the</strong> “hit-or-miss” success rate of recall<br />
of datasets <strong>through</strong> keyword searches alone but also reduce <strong>the</strong> high amounts of irrelevant<br />
returned results in keyword searches.<br />
Figure 8 is a screen capture of <strong>the</strong> search interface in <strong>the</strong> AIP-3 “<strong>Drought</strong>—European”<br />
23 http://www.ogcnetwork.net/pub/ogcnetwork/<strong>GEOSS</strong>/AIP3/pages/Demo.html<br />
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