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1. Domain Dictionaries and Dictionary Extensions

The general purpose technical Gellish English Dictionary may not include all the concepts and definitions that may be required in a particular application domain. Therefore, the Gellish language is extensible with additional vocabulary and grammar. The vocabulary can be extended by means of the definition of additional concepts and the grammar and semantics can be extended by means of the definition of additional relation types. Such additional definitions may be intermingled with other Gellish expressions or they may be collected in a separate amendment. The definition of extensions are themselves also expressed in Gellish.

Organizations that serve a business area, such as branch organizations, may wish to develop a complete Domain Dictionary, using the Gellish Modeling Method. The concepts in such a Domain Dictionary are also arranged in a Taxonomy (a subtype - supertype hierarchy) so that the top concepts in the Domain Dictionary are subtypes of concepts in the Gellish Dictionary. This is necessary to enable semantic verification of the correctness of Gellish expressions when using the concepts from the Domain Dictionary.

To facilitate increase world-wide use of a common language it is strongly recommended to propose extensions to the general Open Source and public domain Gellish English Dictionary via this website.

2. How to define new concepts

2.1 Allocate a Unique identifier (UID)

Any new concept that is added to a Gellish Dictionary or a proprietary or public Domain Dictionary shall be denoted by a new unique Gellish identifier (UID). The concepts shall be referenced in Gellish expressions by those UID's. A new UID shall be selected from available slots in a proprietary range that can be requested from the Gellish language manager or from a range that is outside the reserved range. The range 1-1000 is free for testing and querying purposes and the range 1000 - 300.000.000 is reserved.

2.2 Provide proper definitions

A new concept is properly defined and added to the Gellish language by completion of a single line in a Gellish Table. That line shall contain the following information (that express a main fact and auxiliary facts):

  • A main fact expressed by an explicit specialization relation (‘is specialization of’) between the defined concept and its (existing) direct supertype class (or classes), which expresses that the new class is a subtype of the existing class.

The consistent application of this way of definition causes that the classes are arranged in a hierarchical network. That network is not a pure tree, but a network, due to the fact that a class can be a subtype of more than one supertype class.

  • A textual description that relates the class with a text string that expresses in which respect the subtype is specialized and by what aspects it is distinguished from its ‘sister’ subtypes.
  • A (preferred) name, being an alphanumeric string that expresses how the concept is called in a particular language and within a particular language community (such as a discipline). Names of concepts that are formally added to the Gellish language shall satisfy the rules for names of concepts.
  • A language context that specifies in which language the name (and the definition) is expressed.
  • A language community that provides the context in which this name of the concept is specified as the preferred name and in which context this name is unique (within this context there are no homonyms).
  • Some other auxiliary facts that complete a line in a Gellish Table (this will be self explanetary when you view existing definitions in the Gellish Dictionary (STEPlib).

For example, a cooling system is a system that is intended to be suitable to cool some kinds of things. The concept ‘cooling system’ with this definition can be added to the Gellish Smart Dictionary by specification of a line in a Gellish Database table.

The core of such a line with th definition of a concept is as follows:

UID-1 Name of left hand object Fact IDRelation type IDName of relation typeUID-2Name of right hand object
1cooling system21146is a specialization of3system

Note that the unique identifiers 1, 2 and 3 are selected from a private range. When formally added to the Gellish Dictionary they are allocated by the Gellish language manager. The number 1146 is an example of an identifier that formally identifies the Gellish phrase 'is a specialization of' and that is part of the Gellish language.

2.3 Create Definition Models (optional)

Definitions can be extended with the explicit modeling of facts that are by definition true for any object of such a kind. A definition model is defined as the collection of the facts about a concept (kind of thing) that are by definition true. For example, a pipe has by definition as aspect a diameter and a centrifugal pump has by definition as part an impeller. These facts are expressed in Gellish as follows (ignoring the UID's):

Name of left hand objectName of relation type
pipe has by definition as aspect a
centrifugal pumphas by definition as part a
2.4 Define roles of physical objects

Often a concept is not really a kind of a physical object, but a kind of role, such as a kind of usage or a kind of location of a physical object. For example, the concept 'driver' is a role for which some kinds of physical objects can be used and a 'front end bearing' is not a kind of bearing, but a bearing that is located at a front end (of a shaft). In such cases the concept shall be defined as a subtype of role or one of its subtypes (such as 'usage' or 'located physical object'. br So, such a concept shall be defined by a specialization relation with role. If such a role is by definition fulfilled by a particular kind of physical object, then that fact shall be specified as well. br For example, the concept front end bearing is defined in a Gellish Table as follows (ignoring the unique identifiers and the auxiliary facts):

Name of left hand objectName of relation typeName of right hand object
front end bearingis a specialization ofusage
front end bearingis by definition a role of abearing
2.5 Define roles of aspects

If the name of a kind of aspect contains a name of a kind of physical object, then the kind aspect is normally by definition possessed by that particular kind of physical object. For example, the concept 'impeller diameter' is a diameter that is by definition possessed by an impeller. This means that 'impeller diameter' is not really a kind of aspect, but a kind of 'possessed aspect', (which is a role of an aspect) in a relation with an impeller. If you nevertheless want to add such a concept to the Gellish Dictionary, then you should not only define the concept by a specialization relation with possessed aspect, but you should also specify that it is by definition a possessed aspect of a true aspect and that it is by definition a possessed aspect of a particular kind of physical object. For example:

Name of left hand objectName of relation typeName of right hand object
impeller diameteris a specialization ofpossessed aspect
impeller diameteris by definition a role of adiameter
impeller diameteris by definition a possessed aspect of aimpeller

Note: By defining such a concept in this way the Gellish language enables computers to verify the consistency of two ways of specification: one without decomposition of assemblies and another with decomposition of assemblies. For example, a facility owner may require that a for a centrifugal pump it shall be specified what its impeller diameter is, or which value it shall have, whereas a manufacturer may specify that a delivered centrifugal pump has an impeller and that the impeller has a particular diameter (value). The above specification enables a computer to verify whether the requirement is satisfied, because it can match an impeller diameter of a pump with a diameter of an impeller that is a part of that pump.

2.6 Define qualitative aspects

Conceptual aspects (qualities and properties) such as colour, diameter, material of construction and information shall be distinguished from qualitative aspects, such as red, 6“, stainless steel and standard information. A conceptual aspect shall be defined in the same way as any other concept, such as a kind of physical object: by a specialization relation with its direct supertype. A qualitative aspect shall be defined by an <is a qualification of> relation with the conceptual aspect of which it is a qualification or with a more general qualitative aspect.
For example:

Name of left hand objectName of relation typeName of right hand object
colouris a specialization ofquality
redis a qualification ofcolourwhile being similar to the colour of blood.
gellish_domain_dictionary.1317844729.txt.gz · Last modified: 2017/11/15 11:05 (external edit)