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    | • | 
    System1 Instance of Concept: Date1 
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    – | 
    Attribute: YR =
    Int 1 
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    – | 
    Attribute: MO =
    String “Aug” 
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    Attribute: DY =
    Int 12 
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    System2: Instance of Concept = Date2 
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    Attribute:
    DayOfWeek = Sunday 
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    Attribute:
    ActualDate = 
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       String “12082001” 
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    | • | 
    Semantically
    Equivalent? Then How? 
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