Demo: World Eathquake Map (Yahoo Pipes)

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  • name: Demo: World Eathquake Map (Yahoo Pipes)

live demo here

Facts about this Demonstration

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Technical Highlights

In this demo, we show how RDF can be used to consumed by yahoo! pipes which is a popular web based tool for building Mashups. Following is a step-by-step instruction showing

  • how conventional Web data publishing and consumption can be connected with RDF
  • how RDF + SPARQL can be used to support data manipulation in mashups.


Step 1 locate earthquake data on data.gov
The earthquake dataset published at Data.gov


Step 2 convert earthquake data from CSV to RDF
Web interface of CSV2RDF that was used to convert earthquake data from CSV to RDF
* CSV data: http://www.data.gov/download/34/csv
* xmlbase: http://data-gov.tw.rpi.edu/raw/34
* property namespace: http://data-gov.tw.rpi.edu/vocab/p/32  

note: we reused property namespace from a similar dataset Dataset 32


Step 3 query RDF data and get the results back into a CSV file
  • we use the following query to filter earthquake data by magnitude and depth. Note that some proposed SPARQL 1.1 features were used here including datatype casting (e.g. "xsd:floaf").
PREFIX dgp32:  <http://data-gov.tw.rpi.edu/vocab/p/32/>
PREFIX xsd:  <http://www.w3.org/2001/XMLSchema#> 
SELECT ?id ?label ?datetime  ?lat ?lon (xsd:float(?mag) as ?magnitude) (xsd:float(?dep) as ?depth)  ?region ?src ?uri
FROM <http://data-gov.tw.rpi.edu/raw/34/data-34.rdf>
WHERE { 
         ?uri dgp32:eqid ?id. 
         ?uri dgp32:eqid ?label. 
         ?uri dgp32:region ?region.
         ?uri dgp32:datetime ?datetime. 
	 ?uri dgp32:magnitude ?mag .
         ?uri dgp32:depth ?dep. 
         ?uri dgp32:lat ?lat.
         ?uri dgp32:lon ?lon. 
         ?uri dgp32:src ?src.
         filter ( xsd:float(?mag) >= 3 && xsd:float(?dep) <= 50 )  }
Web interface of SparqlProxy that was used to query earthquake data in RDF and return the results back in CSV
* type of past the above SPARQL query in "SPARQL query" field
* check "CSV"  as output format
* click "query" button
Step 4 build a Yahoo Pipes! demo
  • you need a yahoo ID to access Yahoo Pipes!
  • build a yahoo pipe that consume the filtered CSV and plot the data on a map
    • use "Sources">"Fetch CSV" to retrieve SPARQL query result
    • use "Operations">"rename" to rename column names
    • use "Operations">"Loop" together with "String">"String Builder" to compose a text "description" for each earthquake
    • use "Operations">"Loop" together with "String">"String Builder" to compose a USGS "url" for each earthquake
    • use "Locaiton">"Location Extraction" to put data on map.
Web interface of SparqlProxy display filtered earthquake data (query results in CSV)
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