Changes between Version 5 and Version 6 of ISO15926inOWLLevels
- Timestamp:
- 07/02/08 13:10:46 (16 years ago)
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ISO15926inOWLLevels
v5 v6 14 14 15 15 ---- 16 17 16 == Introduction == 18 19 The initial goal of defining level and type is to add restrictions to the use of the relationships specialization and classification as they are defined in ISO-15926-2:2003. 17 The initial goal of defining level and type is to add restrictions to the use of the relationships specialization and classification as they are defined in ISO-15926-2:2003. 20 18 21 19 In ISO 15926-2:2003 a [http://www.tc184-sc4.org/wg3ndocs/wg3n1328/lifecycle_integration_schema/lexical/specialization.html specialization] is defined as a relationship between two instances of the entity type `class`: 20 22 21 ''A <specialization> is a <relationship> that indicates that all members of the subclass are members of the superclass.'' 23 22 {{{ … … 26 25 superclass : class; 27 26 }}} 28 This definition is too weak as the following illustrates. The definition allows an instance of `class of class of individual` to be declared as a subclass of an instance of a `class of individual`, since both `class of class of individual` and `class of individual` are subtypes of `class`. [http://www.tc184-sc4.org/wg3ndocs/wg3n1328/lifecycle_integration_schema/lexical/class_of_class_of_individual.html class of class of individual] is defined in ISO 15926-2 as 29 ''A <class_of_class_of_individual> is a <class_of_class> whose members are instances of <class_of_individual>'' 30 and [http://www.tc184-sc4.org/wg3ndocs/wg3n1328/lifecycle_integration_schema/lexical/class_of_individual.html class of individual] is defined as 31 ''A <class_of_individual> is a class whose members are instances of <possible_individual>''. 32 Declaring an instance of `class of class of individual` '''A''' as a subclass of an instance of a `class of individual` '''B''' would mean that all the members of '''A''' are also members of '''B''', but that entails that all members of '''A''' are instances of `possible individual` hence violating the definition of `class of class of individual`. 27 28 This definition is too weak as the following example illustrates. The definition allows an instance of `class of class of individual` to be declared as a subclass of an instance of a `class of individual`, since both `class of class of individual` and `class of individual` are subtypes of `class`. [http://www.tc184-sc4.org/wg3ndocs/wg3n1328/lifecycle_integration_schema/lexical/class_of_class_of_individual.html class of class of individual] is defined in ISO 15926-2 as 29 30 ''A <class_of_class_of_individual> is a <class_of_class> whose members are instances of <class_of_individual>'' 31 32 and [http://www.tc184-sc4.org/wg3ndocs/wg3n1328/lifecycle_integration_schema/lexical/class_of_individual.html class of individual] is defined as 33 34 ''A <class_of_individual> is a class whose members are instances of <possible_individual>''. 35 36 Declaring an instance of `class of class of individual` '''A''' as a subclass of an instance of a `class of individual` '''B''' would mean that all the members of '''A''' are also members of '''B''', which entails that all members of '''A''' are also instances of `possible individual`. 37 || [[Image(A.gif)]] || [[Image(B.gif)]] || [[Image(AB.gif)]] || 38 || '''A''' is an instance of `class of class of individual`. All members of '''A''' are instances of `class of individual`. || '''B''' is an instance of `class of individual`. All members of '''B''' are instances of `possible individual`. || '''A''' is a subclass of ''B''. All members of '''A''' are also instances of `possible individual`.|| 33 39 34 40 By adding restrictions to the use of relationships in ISO 15926 we can avoid such problems. The notions defined in this article may also be valuable for adding restrictions to other relationships than specialization and classification defined in ISO 15926-2. 35 41 36 42 == Types and levels == 37 38 43 We want to be able to categorize the entity types defined in ISO 15926-2 into categories, categories which should be non-overlapping. We categorize along two axis. First we observe that a relationship is a different concept than an individual. We call this axis ''type''. 39 44 … … 60 65 61 66 ==== Intuitions ==== 62 63 Intuitively the set Type_Individual is the set containing 67 Intuitively the set Type_Individual is the set containing 68 64 69 * all individuals 65 70 * all sets of individuals … … 68 73 * and so on. 69 74 70 The set Type_Relationship is the set containing 75 The set Type_Relationship is the set containing 76 71 77 * all relationships between individuals 72 78 * all sets of relationships between individuals … … 80 86 * and so on. 81 87 82 83 88 === Definition in OWL === 84 85 89 {{{ 86 90 Class: Type_Individual … … 112 116 Level_2 113 117 }}} 114 115 Note: Defining all levels as mutually disjoint is not correct according to the set theoretical definition above; the empty set is a member of all sets. A possible solution is to define a "ISO 15926 notion" of level. In ISO 15926-2 the empty set is an instance of the entity type [http://www.tc184-sc4.org/wg3ndocs/wg3n1328/lifecycle_integration_schema/lexical/class.html class]. 118 Note: Defining all levels as mutually disjoint is not correct according to the set theoretical definition above; the empty set is a member of all sets. A possible solution is to define a "ISO 15926 notion" of level. In ISO 15926-2 the empty set is an instance of the entity type [http://www.tc184-sc4.org/wg3ndocs/wg3n1328/lifecycle_integration_schema/lexical/class.html class]. 116 119 117 120 == Restricting ISO 15926-2 entity types to levels == 118 119 121 This section places most entity types defined in ISO 15926 on the level axis, in either Level 0, Level 1, Level 2 or Level 3. 120 122 … … 203 205 }}} 204 206 == Adding restrictions to relations using levels == 205 206 This section adds restrictions to relations defined in ISO 15926 using levels. 207 This section adds restrictions to relations defined in ISO 15926 using levels. 207 208 208 209 === Specialization === 209 210 [http://www.tc184-sc4.org/wg3ndocs/wg3n1328/lifecycle_integration_schema/lexical/specialization.html Specialization] is in ISO 15926-2 defined as: 211 210 212 ''A <specialization> is a <relationship> that indicates that all members of the subclass are members of the superclass. <specialization> is transitive. '' 211 213 {{{ … … 220 222 221 223 OWL listing: 224 222 225 {{{ 223 226 Class: part2:Specialization … … 241 244 }}} 242 245 === Classification === 243 244 246 [http://www.tc184-sc4.org/wg3ndocs/wg3n1328/lifecycle_integration_schema/lexical/classification.html Classification] is defined as 247 245 248 ''A <classification> is type of <relationship> that indicates that the classified <thing> is a member of the classifier <class>. <classification> is not transitive.'' 246 249 {{{ … … 252 255 253 256 OWL listing: 257 254 258 {{{ 255 259 Class: part2:Classification … … 264 268 and part2:hasClassifier only Level_3 265 269 }}} 266 267 268 270 ---- 269 270 271 [[ViewTopic(ISO 15926 in OWL, adding restrictions to relationships)]]
