====================================
1.0 Release Candidate 2 - May 2013
====================================
* Amended Package "«ApplicationSchema» WMO METCE" to be re-named "METCE"
* Changed targetNamespace for Package "«ApplicationSchema» METCE" to: http://def.wmo.int/metce/2013
* Changed version for Package "«ApplicationSchema» METCE" to 1.0RC2
* Change xsdDocument tagged value for Package "«Leaf» Observation and Measurement Types" to 
    "observation-types.xsd"; general style change for file-names to be all lower-case
- Removed Class "«enumeration» ExpectedIntensityChange" from Package "«Leaf» Qualifiers"; this now found 
    within IWXXM Package "«Leaf» SIGMET" 
- Removed Class "«enumeration» ForecastChangeIndicator" from Package "«Leaf» Qualifiers"; this now found 
    within IWXXM Package "«Leaf» METAR/SPECI"
- Removed the (now empty) Package "«Leaf» Qualifiers"
- Removed Classes "«CodeList» MeteorologicalPhenomenon" and "«CodeList» AeronauticalSignificantWeatherPhenomenon" 
    (and associated context diagram) from Package "«Leaf» Meteorological Phenomena"; in line with changes 
    surrounding MetBasic (see Release Notes), such «CodeList» classes are anticipated to be provided within 
    domain/industry specific «Application Schema» such as IWXXM which will directly reference the appropriate 
    WMO code-table
- Removed stereotype «Type» from Class "MeasurementContext" from Package "«Leaf» Procedure"; use of this 
    stereotype is deprecated in favour of un-stereotyped Classes
* Within Package "«Leaf» Procedure" amend target of Association "MeasurementContext" (role name "context") 
    to connect directly to Class "MeasurementContext" enabling some unnecessary complexity to be removed from
    the model (see below)
- Remove Classes "AbstractMeasurementContext" and "CompositeMeasurementContent" from Package "«Leaf» Procedure"; 
    the additional complexity introduced by these classes is unwarranted given that the Association Role 
    "context" from Class "«FeatureType» Process" has cardinality [0..*] (e.g. multiple "contexts" can be 
    specified directly without the need for composition)
* Renamed Attribute "uom" (Class "MeasurementContext" from Package "«Leaf» Procedure") to "unitOfMeasure"; this 
    attribute is type UnitOfMeasure (from ISO 19103 Basic-types) which itself includes the attribute "uom" - the 
    resulting serialisation would appear odd
* Amended (the renamed) Attribute "unitOfMeasure" from Class "MeasurementContext" to be optional (e.g. cardinality 
    [0..1]) as one may not want to specify the unit of measurement in all cases
+ Added constraint to Class "MeasurementContext" from Package "«Leaf» Procedure" to the effect that: 
    { if measuringInterval or resolutionScale or both are given then uom must also be provided } 
* Amended documentation for Class "«Feature Type» Volcano" from Package "«Leaf» Meteorological Phenomena" 
    indicating guidance regarding the source of names for Volcano / EruptingVolcano; "Global Volcanism Program" 
    (http://www.volcano.si.edu/world/find_names.cfm)
* Amended Attribute “documentationRef” from Class “«FeatureType» Process” (Package "«Leaf» Procedure") such that 
    cardinality is [0..1]; the previous specification of Attribute "documentationRef" is overly strict as a data 
    publisher may be choose to embed a “gml:description” element, a default element available to all GML objects, 
    within the data to describe the procedure rather than referring to an online description (e.g. when defining 
    procedures at a fine level of granularity such as a given sensor in a particular calibrated state)  
* Amended as necessary values for taggedValue "sequenceNumber" to ensure correct ordering of properties in 
    resulting XSD serialisation; paying particular attention to Associations
* Various improvements in model documentation

=======================================
1.0 Release Candidate 1 - December 2012
=======================================
Initial model release.

====================================
1.0 Release Candidate 2 - May 2013
====================================
* Changed targetNamespace for Package "«ApplicationSchema» OPM" to: http://def.wmo.int/opm/2013
* Changed version for Package "«ApplicationSchema» OPM" to 1.0RC2
* Renamed Package "«Leaf» ObservableProperty" to "«Leaf» Observable Property"
* Changed xsdDocument tagged value for (re-named) Package "«Leaf» Observable Property" to 
    "observable-property.xsd"; general style change for file-names to be all lower-case
- Removed stereotype «Type» from Class "ObservableProperty" from Package "«Leaf» Procedure"; 
    use of this stereotype is deprecated in favour of un-stereotyped Classes
- Removed stereotype «Type» from Class "AbstractObservableProperty" from Package "«Leaf» Procedure"; 
    use of this stereotype is deprecated in favour of un-stereotyped Classes
- Removed stereotype «Type» from Class "CompositeObservableProperty" from Package "«Leaf» Procedure"; 
    use of this stereotype is deprecated in favour of un-stereotyped Classes
- Removed stereotype «Type» from Class "QualifiedObservableProperty" from Package "«Leaf» Procedure"; 
    use of this stereotype is deprecated in favour of un-stereotyped Classes
* Updated URI for "vocabulary" tagged value for Class "«CodeList» StatisticalFunctionCode" defined 
    in Package "«Leaf» Observable Property": "http://codes.wmo.int/grib2/codeflag/4.10"
* Amended documentation for Class "«CodeList» StatisticalFunctionCode" to refer to (primarily) "WMO No. 
    306 Vol I.2 Part B FM 92 GRIB code-table 4.10 'Type of statistical processing'" and (supplemental) 
    "WMO No. 306 Vol I.2 Part B FM 94 BUFR code-table 0 08 023 'First-order statistics'"
* Updated "codeSpace" tagged value for Class "«CodeList» StatisticalFunctionCode" defined in Package 
    "«Leaf» Observable Property": "http://codes.wmo.int/grib2"
* Updated "dictionaryIdentifier" tagged value for Class "«CodeList» StatisticalFunctionCode" defined 
    in Package "«Leaf» Observable Property": "http://codes.wmo.int/grib2/codeflag/4.10"
* Updated "memberIdentifierStem" tagged value for Class "«CodeList» StatisticalFunctionCode" defined 
    in Package "«Leaf» Observable Property": "http://codes.wmo.int/grib2/codeflag/4.10"
* Updated Attribute "aggregationTimePeriod" (Class "«DataType» StatisticalQualifier" from Package 
    "«Leaf» Observable Property") to specify type TM_PeriodDuration (from ISO 19108)
* Amended name of Attribute "uom" from Classes "QualifiedObservableProperty", "«DataType» 
    ScalarConstraint" and "«DataType» RangeConstraint" to "unitOfMeasure"; this attribute is type 
    UnitOfMeasure (from ISO 19103 Basic-types) which itself includes the attribute "uom" - the resulting 
    serialisation would appear odd 
* Amended Attribute “unitOfMeasure” from Classes “«DataType» ScalarConstraint“ and “«DataType» 
    RangeConstraint“ to have cardinality [0..1]; amended following assessment of INSPIRE implementation of 
    the Observable Property Model
* Amended ordering of Attributes from Class "«DataType» ScalarConstraint" to ensure that "unitOfMeasure"
    precedes "value"; set taggedValue "sequenceNumber" accordingly
* Amended taggedValues for Attribute "count" from Class "CompositeObservableProperty" to allow 
    serialisation as XML attribute; xsdAsAttribute = "true"
+ Added new Class “«enumeration» ComparisonOperator” to provide a set of (simple) mathematical operators 
    (e.g. “ne”, “lt”, “le”, “eq”, “ge”, “gt”) – this shall be equivalent to the INSPIRE Class “«enumeration» 
    ComparisonOperatorValue” that has values “equalTo”, “notEqualTo”, “lessThan”, “greaterThan”, 
    “lessThanOrEqualTo” and “greaterThanOrEqualTo”; included following assessment of INSPIRE implementation 
    of the Observable Property Model
* Amended Attribute “value” from Class “«DataType» ScalarConstraint" to specify type "Number"
+ Added Attribute “comparisonOperator” (type “«enumeration» ComparisonOperator”) to Class “«DataType» 
    ScalarConstraint” with cardinality [1]; mark for serialisation as XML Attribute by specifying taggedValue 
    xsdAsAttribute = "true"; included following assessment of INSPIRE implementation of the Observable 
    Property Model
+ Added Attributes “startComparison” and “endComparison” (both type “«enumeration» ComparisonOperator”) to 
    Class “«DataType» RangeBounds” with cardinality [1]; mark both Attributes for serialisation as XML 
    attribute by specifying taggedValue xsdAsAttribute = "true"; added following assessment of INSPIRE 
    implementation of the Observable Property Model
* Amended as necessary values for taggedValue "sequenceNumber" to ensure correct ordering of properties in 
    resulting XSD serialisation; paying particular attention to Associations
* Various improvements in model documentation

Note: for 1.0 Release Candidate 2 the WMO codes registry is deployed at http://test.wmocodes.info
    rather than the eventual target location of http://codes.wmo.int

=======================================
1.0 Release Candidate 1 - December 2012
=======================================
Initial model release based on work from Open Geospatial Consortium (OGC) Sensor Web Enablement (SWE)
    standards working group and subsequent revision within INSPIRE Data Specification Thematic Working 
    Groups.

====================================
1.0 Release Candidate 2 - May 2013
====================================
- MetBasic removed from the WMO logical model structure. Met-Basic was intended to ensure that the semantics 
    defined in the WMO code-tables was applied within Application Schemas using METCE; this _was_ achieved 
    through provision of a palette of reusable “quantity value” and «CodeList» classes. However, in hindsight, 
    this resulted in coupling the model directly to the WMO code-tables and was a poor design choice that 
    introduced unnecessary redundancy and inhibiting the flexibility of the model with respect to changes 
    in the WMO code-tables.
    
    The functionality of the now defunct MetBasic model is now delivered as follows:
    (a) Within Application Schema (e.g. IWXXM) each quantity value property (e.g. "dewPointTemperature") will
    be specified as type "Measure" (from ISO 19103 Basic-types) - or a standard sub-type of "Measure" (e.g. 
    "Length") as defined in ISO 19103 Basic-types). Furthermore, each quantity value property will be
    annotated with a tagged value "quantity" that refers to the semantic definition of the quantity within
    the WMO codes registry[1] (e.g. for dewPointTemperature "quantity" = 
    "http://codes.wmo.int/common/c-15/me/dewPointTemperature"). It is this reference to an authoritative 
    definition that ensures consistent use of semantics.
    (b) «CodeList» classes (e.g. "RunwayDeposits") are defined directly within Application Schema (e.g. IWXXM) 
    for each nominal value property (e.g. "depositType", of type «CodeList» "RunwayDeposits"). The «CodeList» 
    classes are annotated with tagged values "vocabulary" (to refer to the appropriate code-table from the WMO 
    codes registry) and "extensibility" (to assert the validation regime to be used) as used in 1.0 Release 
    Candidate 1 within MetBasic (e.g. for RunwayDeposits "vocabulary" = 
    "http://codes.wmo.int/bufr4/codeflag/0-20-086" and "extensibility" = "none"). 
    
    As a result, all «CodeList» classes from MetBasic are now migrated to IWXXM. 
    
    Additionally note that, Class “«enumeration» RunwayVisualRangeTendency” (from Package “«Leaf» 
    PhysicalAtmosphericProperties - Aeronautical” is also migrated to IWXXM Package "«Leaf» METAR/SPECI" 
    where it is now named “«enumeration» VisualRangeTendency”.
    
    [1] note that for 1.0 Release Candidate 2 the WMO codes registry is deployed at http://test.wmocodes.info
    rather than the eventual target location of http://codes.wmo.int

=======================================
1.0 Release Candidate 1 - December 2012
=======================================
Initial model release.

====================================
1.0 Release Candidate 2 - May 2013
====================================
* Updated IWXXM to match anticipated changes in ICAO Annex 3 Amendment 76
    * Moved forecastPosition from VA/TC SIGMET onto SIGMET (all SIGMETs may have forecast positions)
    - removed braking action from METAR/SPECI
    * renamed frictionCoefficient to estimatedSurfaceFriction
    - removed 1-minute minimum/maximum for RVR
    + added significant wave height onto METAR/SPECI
* Package renamed from "ICAO Weather Information Exchange Model" to "ICAO Meteorological Exchange Model"
    to address translation issues.  The abbreviated model name "IWXXM" remains unchanged
* SIGMET amended to allow for cancellations, including supporting constraints
* TAF amended to properly allow for CORRECTED, AMENDED, and CANCELLED status with the appropriate rules
    on present and missing information
* Significant updates to documentation to improve correctness and clarity
* Added support for METAR/SPECI and TAF NIL reports
* CodeLists moved from MetBasic and METCE into IWXXM
* Measure types from MetBasic were changed into GML Measure types

* METAR, SPECI, TAF, and SIGMET now have the <<FeatureType>> stereotype
* Removed <<Type>> stereotype from a number of classes
* Corrected surface wind properties on TAF, including fixes to variable wind directions and averages
* AerodromeHorizontalVisibility fixed to no longer require a minimum visibility direction when
    minimumVisibility is reported
+ Added new constraint to MeteorologicalAerodromeObservationRecord to ensure that if prevailingVisibility
    is less than 1500m then rvr must be reported
+ Added constraint onto AerodromeObservedClouds to ensure that if amountAndHeightUnobservableByAutoSystem
    is true then no cloud layers are reported
- Removed constraint on reported surface winds on METAR, SPECI, and TAF when CAVOK is reported
+ Added constraint to ensure that reported clouds and weather are missing when CAVOK is true
* Renamed "Context Diagram: Present Weather" to "Context Diagram: Surface Wind"
* Fixed METAR/SPECI, TAF, and SIGMET to ensure that XML element order more closely matches that of the corresponding
    ICAO Annex 3 Templates
- Removed humanReadableText from all reports
* Clarified documentation on how "TX" and "TN" maps into IWXXM
* Corrected documentation and constraint to indicate that SIGMETs are reported on FIRs, UIRs, and CTAs rather
    than just FIRs
* MeteorologicalAerodromeForecastRecord amended to ensure the CAVOK constraint on horizontal visibility
    refers to the correct name ("prevailingHorizontalVisibility instead of horizontalVisibility)
* METAR/SPECI amended to allow any number of runway states
* MeteorologicalAerodromeObservationRecord.recentWeather now has cardinality 0..3
* AerodromeRunwayState.estimatedSurfaceFriction now has a constraint to restrict values between 0.0 and 0.9
* Renamed ceilingAndVisibilityOK to cloudAndVisibilityOK on all classes
* AerodromeObservedClouds stereotype changed so it is nillable
* "Terminal Aerodrome Forecast" changed to "Aerodrome Forecast" to match current ICAO definition
- Removed HTML-like styling from many parts of the documentation to ensure proper translation to XML
+ unreliableFrictionCoefficient boolean flag added to AerodromeRunwayState
* Added a boolean onto AerodromeRunwayState to support runway conditions being reported on all runways at once.
    Changed the names of similar constructs on AerodromeWindShear for consistency
* Removed nilReason URIs from the model.  All nil reason base URIs changed from ttp://data.wmo.int/def/nil-reason
    to http://codes.wmo.int/common/nil
* Changed SAF references to mirror changes to simplified AIXM representations
- cloudType removed from CloudLayer

=======================================
1.0 Release Candidate 1 - December 2012
=======================================
Initial model release including complete representations of METAR, SPECI, TAF and SIGMET
from ICAO Annex 3 Amendment 75.

====================================
1.0 Release Candidate 2 - May 2013
====================================
* Changed the package name from "Simple Aviation Features" to "Simple Aeronautical Features"
* Replaced all aeronautical features with simplified versions of AIXM classes.
    For example, FIR was replaced by the AIXM class named Airspace with type "FIR", and the MWO class was
    replaced by the AIXM class named Unit with appropriate type
    AirportHeliport was named Aerodrome
+ Added location and identification information for all aeronautical features in a form consistent with
    AIXM (see above)
+ Added examples of several SAF features

=======================================
1.0 Release Candidate 1 - December 2012
=======================================
Initial model release including simplified representations of AirspaceSolid and the
aeronautical domain features required by ICAO Annex 3 Amendment 75.