how to represent GRAI->SSCC->ISIN?

[VladimirAlexiev]

Hi @philarcher and @mgh128 ! I want to represent the following business situation:

• Documents that initiate and support the business transaction (gs1:Document, epcis:BizTransaction):
  • The Client Company makes and sends a po Purchase Order
  • The Production Company makes and sends an inv Invoice
• A crate is picked (GRAI ReturnableAsset)
  • A sensor (GRAI or GIAI, SensorDevice) is attached inside the crate (EVENT04)
    • Following EPCIS best practices, we use the AssociationEvent: assembling things, e.g. attaching sensor to asset
  • The two products are packed together in the crate (EVENT05)
    • Following EPCIS best practices, we use the AggregationEvent: packing goods in crates, putting crates on pallets, putting pallets in containers
• This loaded crate (two products plus sensor) is allocated a SSCC LogisticUnit (EVENT06)
• A GSIN Shipment identifier is allocated (EVENT07) and the crate is shipped
  • The two business documents are linked to this event
  • The two companies and their locations are designated as the ultimate source and destination of the shipment

I'm struggling how to represent the transition from GRAI (a crate) to SSCC (a loaded crate) to ISIN (a shipment).
Here's what I've come up with:

<$EVENT04> a epcis:AssociationEvent
  epcis:action               "ADD" ;
  epcis:bizLocation          <$SGLN_PLANT5> ;
  epcis:readPoint            <$SGLN_PLANT5/254/235> ;
  epcis:bizStep              cbv:BizStep-assembling ;
  epcis:disposition          cbv:Disp-in_progress ;
  epcis:parentID             <$GRAI_CRATE1>;
  epcis:childEPCs            <$GIAI_SENSOR1>;
  epcis:eventTime            "2021-04-04T22:41:01.123+08:00"^^xsd:dateTimeStamp ;
  epcis:recordTime           "2021-04-04T22:41:01.123+08:00"^^xsd:dateTimeStamp ;
  epcis:eventTimeZoneOffset  "+08:00".

<$EVENT05> a epcis:AggregationEvent;
  epcis:action               "ADD" ;
  epcis:bizLocation          <$SGLN_PLANT5> ;
  epcis:readPoint            <$SGLN_PLANT5/254/235> ;
  epcis:bizStep              cbv:BizStep-assembling ;
  epcis:disposition          cbv:Disp-in_progress ;
  epcis:parentID             <$GRAI_CRATE1>;
  epcis:childEPCs            <$SGTIN_PRODUCT1>;
  epcis:childQuantityList    [a epcis:QuantityElement;
    epcis:epcClass           <$LGTIN_PRODUCT2> ;
    epcis:quantity           "200.5"^^xsd:double ;
    epcis:uom                "KGM"];
  epcis:eventTime            "2021-04-04T22:41:01.123+08:00"^^xsd:dateTimeStamp ;
  epcis:recordTime           "2021-04-04T22:41:01.123+08:00"^^xsd:dateTimeStamp ;
  epcis:eventTimeZoneOffset  "+08:00".

<$EVENT06> a epcis:ObjectEvent;
  epcis:action               "ADD" ;
  epcis:bizLocation          <$SGLN_PLANT5> ;
  epcis:readPoint            <$SGLN_PLANT5/254/235> ;
  epcis:bizStep              cbv:BizStep-assembling ;
  epcis:disposition          cbv:Disp-in_progress ;
  epcis:parentID             <$SSCC_UNIT1>;
  epcis:childEPCs            <$GRAI_CRATE1>;
  epcis:eventTime            "2021-04-04T22:41:01.123+08:00"^^xsd:dateTimeStamp ;
  epcis:recordTime           "2021-04-04T22:41:01.123+08:00"^^xsd:dateTimeStamp ;
  epcis:eventTimeZoneOffset  "+08:00".

<$EVENT07> a epcis:TransactionEvent;
  epcis:action               "ADD" ;
  epcis:bizLocation          <$SGLN_PLANT5> ;
  epcis:readPoint            <$SGLN_PLANT5/254/235> ;
  epcis:bizStep              cbv:BizStep-shipping ;
  epcis:disposition          cbv:Disp-in_progress ;
  epcis:epcList              <$SSCC_UNIT1>, <$GSIN_SHIPMENT1>;
  epcis:bizTransactionList   <$GDTI_PO9>, <$GDTI_INV5>;
  epcis:sourceList           <$PGLN_COMPANY5#possessing>, <$SGLN_PLANT5#location>;
  epcis:destinationList      <$PGLN_COMPANY9#possessing>, <$SGLN_SITE9#location>;
  epcis:eventTime            "2021-04-04T22:41:01.123+08:00"^^xsd:dateTimeStamp ;
  epcis:recordTime           "2021-04-04T22:41:01.123+08:00"^^xsd:dateTimeStamp ;
  epcis:eventTimeZoneOffset  "+08:00".

I'm unsure about the type, action, bizStep, disposition of EVENT06, EVENT07.

• EVENT06 puts the GRAI as a singleton child of SSCC, is this right?
• EVENT07 mentions the SSCC, GSIN as siblings but SSCC is logically a "lower-level" object than GSIN?
• Or maybe I'm over-complicating and I should use just one of the two (GSIN)?

(Notes):

• The $VARs are Digital Link (id.epcis.org) URLs of appropriate form
• I have definitions of the subsidiary objects like <$GDTI_INV5>, <$PGLN_COMPANY5#possessing> etc that are shown below

[VladimirAlexiev]

Subsidiary objects:

<$GDTI_PO9> a gs1:Document, epcis:BizTransaction;
  schema:identifier [a schema:PropertyValue; schema:propertyID "GDTI"; schema:value "$GDTI_PO9"];
  epcis:bizTransactionType cbv:BTT-po; schema:name "purchase order";
  schema:author <$PGLN_COMPANY9>; 
  schema:dateIssued "2021-02-27"^^xsd:date.

<$GDTI_INV5> a gs1:Document, epcis:BizTransaction; 
  epcis:bizTransactionType cbv:BTT-inv; schema:name "invoice";
  schema:author <$PGLN_COMPANY5>; 
  schema:dateIssued "2021-04-04"^^xsd:date.

<$PGLN_COMPANY9#possessing> a epcis:SourceOrDestination;
  epcis:sourceOrDestination <$PGLN_COMPANY9>;
  epcis:sourceOrDestinationType cbv:SDT-possessing_party.

<$SGLN_PLANT5#location> a epcis:SourceOrDestination;
  epcis:sourceOrDestination <$SGLN_PLANT5>;
  epcis:sourceOrDestinationType cbv:SDT-location.

<$PGLN_COMPANY5#possessing> a epcis:SourceOrDestination;
  epcis:sourceOrDestination <$PGLN_COMPANY5>;
  epcis:sourceOrDestinationType cbv:SDT-possessing_party. 

<$SGLN_SITE9#location> a epcis:SourceOrDestination;
  epcis:sourceOrDestination <$SGLN_SITE9>;
  epcis:sourceOrDestinationType cbv:SDT-location.

<$GRAI_CRATE1> a gs1:ReturnableAsset;
  schema:identifier [a schema:PropertyValue; schema:propertyID "GRAI"; schema:value "$GRAI1"].

<$SSCC_UNIT1> a gs1:LogisticUnit;
  schema:identifier [a schema:PropertyValue; schema:propertyID "SSCC"; schema:value "$SSCC1"].

<$GSIN_SHIPMENT1> a gs1:Shipment;
  schema:identifier [a schema:PropertyValue; schema:propertyID "GSIN"; schema:value "$GSIN1"].

[VladimirAlexiev]

Hi @mgh128 and @philarcher Could you shed some light on this?
After the holidays we're continuing our effort to present an integrated EPCIS and WebVoc "data story".

But this issue has tripped us up:
I don't know how to represent the "evolution" from GRAI (a crate) to SSCC (a loaded crate) to ISIN (a shipment).