Common use of Modification Protocol Clause in Contracts

Modification Protocol. We intend to allow participants to specify SHACL shapes [14] defining the infor- mation they require their counterpart to provide. Moreover, executing SPARQL queries [2] over the conversation dataset can be useful for a number of use cases. However, for accurately representing a shared model of the conversation content, it is necessary to allow participants to change their mind or to correct mistakes, which means, there must be a way to modify past messages. Modifying is only allowed in one way: by marking one’s own earlier messages as no longer to be considered or, as we will call it in the remainder of this work, as retracted. For modelling the modification of messages, we introduce the Modification ontology5, prefixed ’mod’. It specifies only one ObjectProperty, mod:retracts, that is used in triples linking two message IRIs, the subject being the retracting message, the object being the retracted message. I × C → P I The function retracts : ( ) returns all message IRIs linked to from the input message via mod:retracts in any of its content graphs. The function isRetracted : I × C → {true, false} is defined as follows: isRetracted(m, C) = m ∈ iris(C) ∧ ∃r ∈ iris(C) : m ∈ retracts(r, C) ∧ sender(m, C) = sender(r, C) ∧ happenBefore(r, m, C) = true

Modification Protocol. We intend to allow participants to specify SHACL shapes [14] defining the infor- mation they require their counterpart to provide. Moreover, executing SPARQL queries [2] over the conversation dataset can be useful for a number of use cases. However, for accurately representing a shared model of the conversation content, it is necessary to allow participants to change their mind or to correct mistakes, which means, there must be a way to modify past messages. Modifying is only allowed in one way: by marking one’s own earlier messages as no longer to be considered or, as we will call it in the remainder of this work, as retracted. For modelling the modification of messages, we introduce the Modification ontology5ontology4, prefixed ’mod’. It specifies only one ObjectProperty, mod:retracts, that is used in triples linking two message IRIs, the subject being the retracting message, the object being the retracted message. I × C → P I The function retracts : ( ) returns all message IRIs linked to from the input message via mod:retracts in any of its content graphs. The 4 See xxxx://xxxx.xxx/webofneeds/modification [2017/07/23]. function isRetracted : I × C → {true, false} is defined as follows: isRetracted(m, C) = m ∈ iris(C) ∧ ∃r ∈ iris(C) : m ∈ retracts(r, C) ∧ sender(m, C) = sender(r, C) ∧ happenBefore(r, m, C) = true

Modification Protocol. We intend to allow participants to specify SHACL shapes [1415] defining the infor- mation they require their counterpart to provide. Moreover, executing SPARQL queries [2] over the conversation dataset can be useful for a number of use cases. However, for accurately representing a shared model of the conversation content, it is necessary to allow participants to change their mind or to correct mistakes, which means, there must be a way to modify past messages. Modifying is only allowed in one way: by marking one’s own earlier messages as no longer to be considered or, as we will call it in the remainder of this work, as retracted. For modelling the modification of messages, we introduce the Modification ontology5, prefixed ’mod’. It specifies only one ObjectProperty, mod:retracts, that is used in triples linking two message IRIs, the subject being the retracting message, the object being the retracted message. I × C → P I The function retracts : ( ) returns all message IRIs linked to from the input message via mod:retracts in any of its content graphs. The function isRetracted : I × C → {true, false} is defined as follows: isRetracted(m, C) = m ∈ iris(C) ∧ ∃r ∈ iris(C) : m ∈ retracts(r, C) ∧ sender(m, C) = sender(r, C) ∧ happenBefore(r, m, C) = true