/semtools-dwc-oboe-example

Document Status: Obsolete
Document moved to https://sonet.ecoinformatics.org/observational-data-use-cases/oboe-representation-examples

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This is an attempt to represent a DarwinCore observational data record as an OBOE structure. The DwC record came form the Darwin Core examples website (http://code.google.com/p/darwincore/wiki/Examples), and is reproduced here for convenience.

Darwin Core record of a preserved mammal specimen
------------------------------------------------
dcterms:type=PhysicalObject
dcterms:modified=2009-02-12T12:43:31
dwc:institutionCode=MVZ
dwc:collectionCode=Mammals
dwc:catalogNumber=14523
dwc:collectionID=urn:lsid:biocol.org:col:34904
dwc:occurrenceID=urn:catalog:MVZ:Mammals:14523
dwc:basisOfRecord=PreservedSpecimen
dwc:establishmentMeans=wild
dwc:country=Argentina
dwc:countryCode=AR
dwc:stateProvince=Neuquén
dwc:locality=25 km al NNE de Bariloche por Ruta 40 (=237)
dwc:scientificName=Ursus arctos

Pseudorepresentation in OBOE
----------------------------
observation "o1"
entity "countries:Argentina"
measurement "c1"
    characteristic "dwc:countryCode"
    value "AR"
    standard "iso:countryCode"

observation "o2"
entity "provinces:Nequen"
context "oboe-rel:within" "o1"

observation "o3"
entity "sbc:SpatialLocation"
measurement "m1"
    characteristic "dwc:locality"
    value "locality=25 km al NNE de Bariloche por Ruta 40 (=237)"
context "oboe-rel:within" "o2"

observation "o5"
entity "sbc:SamplingEvent"
measurement "m12"
    characteristic "dcterms:type"
    value "PhysicalObject"
measurement "m13"
    characteristic "dcterms:modified"
    value "2009-02-12T12:43:31"
measurement "m14"
    characteristic "dwc:institutionCode"
    value "MVZ"
measurement "m15"
    characteristic "dwc:collectionCode"
    value "Mammals"
measurement "m30"
    characteristic "dwc:catalogNumber"
    value "14523"
measurement "m31"
    characteristic "dwc:collectionID"
    value "urn:lsid:biocol.org:col:34904"
measurement "m32"
    characteristic "dwc:establishmentMeans"
    value "wild"
measurement "m16"
    characteristic "dwc:basisOfRecord"
    value "PreservedSpecimen"
context "oboe-rel:within" "o3"

observation "o6"
entity "sbc:Organism"
measurement "m17"
    characteristic "dwc:occurrenceID"
    value "urn:catalog:MVZ:Mammals:14523"
measurement "m18"
    characteristic "dwc:scientificName"
    value "Ursus arctos"
context "oboe-rel:within" "o5"

Darwin Core record of bird observation
--------------------------------------
dwc:occurrenceID=urn:catalog:AUDCLO:EBIRD:OBS64515288
dcterms:type=Event
dcterms:modified=2009-02-17T07:33:04Z
dwc:institutionCode=AUDCLO
dwc:collectionCode>EBIRD
dwc:basisOfRecord>HumanObservation
dwc:individualCount>2
dwc:eventID>http://guid.mvz.org/events/2006/11/26/17
dwc:samplingProtocol>area count
dwc:eventDate>2006-11-26
dwc:locationID>http://guid.mvz.org/sites/arg/127
dwc:country>Argentina
dwc:countryCode>AR
dwc:stateProvince>Neuquén
dwc:locality>Valle Limay, Estancia Rincon Grande, 48 ha area with centroid at this point
dwc:decimalLatitude>-40.97467
dwc:decimalLongitude>-71.0734
dwc:geodeticDatum>WGS84
dwc:coordinateUncertaintyInMeters>200
dwc:scientificName>Anthus hellmayri
dwc:class>Aves
dwc:genus>Anthus
dwc:specificEpithet>hellmayri

Pseudorepresentation in OBOE
----------------------------

observation "o1"
entity "countries:Argentina"
measurement "c1"
    characteristic "dwc:countryCode"
    value "AR"
    standard "iso:countryCode"

observation "o2"
entity "provinces:Nequen"
context "oboe-rel:within" "o1"

observation "o3"
entity "sbc:SpatialLocation"
measurement "m0"
    characteristic "dwc:locationID"
    value "http://guid.mvz.org/sites/arg/127"
    standard "foobar:ID"
measurement "m1"
    characteristic "dwc:locality"
    value "Valle Limay, Estancia Rincon Grande, 48 ha area with centroid at this point"
measurement "m2"
    characteristic "dwc:decimalLatitude"
    value "-40.97467"
    standard "oboe-units:Degree"
     precision "0.0018"                       <== REPRESENTS 200m uncertainty
measurement "m3"
    characteristic "dwc:decimalLongitude"
    value "-71.0734"
    standard "oboe-units:Degree"
     precision "0.0018"                       <== REPRESENTS 200m uncertainty
measurement "m4"
    characteristic "dwc:geodeticDatum"
    value "WGS84"
context "oboe-rel:within" "o2"

observation "o4"
entity "sbc:TemporalPoint"
measurement "m11"
    characteristic "dwc:eventDate"
    value "2006-11-26"
    standard "oboe-units:Date"

observation "o5"
entity "sbc:SamplingEvent"
measurement "m10"
    characteristic "dwc:eventID"
    value "http://guid.mvz.org/events/2006/11/26/17"
    standard "foobar:ID"
measurement "m12"
    characteristic "dcterms:type"
    value "Event"
measurement "m13"
    characteristic "dcterms:modified"
    value "2009-02-17T07:33:04Z"
measurement "m14"
    characteristic "dwc:institutionCode"
    value "AUDCLO"
measurement "m15"
    characteristic "dwc:collectionCode"
    value "EBIRD"
measurement "m16"
    characteristic "dwc:basisOfRecord"
    value "HumanObservation"
context "oboe-rel:within" "o3"
context "oboe-rel:within" "o4"

observation "o7"
entity "foobar:CollectionOfOrganisms"
measurement "m17"
    characteristic "dwc:occurrenceID"
    value "urn:catalog:AUDCLO:EBIRD:OBS64515288"
measurement "m18"
    characteristic "dwc:scientificName"
    value "Anthus hellmayri"
measurement "m19"
    characteristic "dwc:class"
    value "Aves"
measurement "m20"
    characteristic "dwc:genus"
    value "Anthus"
measurement "m21"
    characteristic "dwc:specificEpithet"
    value "hellmayri"
measurement "m22"
    characteristic "dwc:individualCount"
    value "2"
    standard "oboe-units:Number"
    protocol "area count"
context "oboe-rel:within" "o5"


NOTE on calculating precision in decimal degrees
------------------------------------------------
Differences in decimal degrees were converted to meters based on the WGS-84 Equatorial Radius, which is 6378137.0 meters. Thus, at the equator, one degree is equal to 111319.5 m.

Thus, 1 degree       200 m
       ---------- x          = 0.0018 m
       111319.5 m

This is not universally useful, in that the ratio of degrees to meters changes with distance from the equator. To calculate decimal degrees for 200 m at other locations, one could apply a cosine correction as a function of latitude, such that the radius is 110895.9 m at +/- 5°, 109628.3 m at +/- 10°, 107526.4 m at +/- 15°, and 104606.1 m at +/- 20°.

Thus, the OBOE approach in which we expect to express precision in the same units as the value is somewhat unsatisfactory in the case of latitude and longitude, even though it works fine for other physical quantities.