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11.3.2. Conceptualization of Verbs

Verbs represent actions in the domain. The verbs dictionary expresses declaratively the meaning of each verb declaratively by identifying the following fields: Verb name; Attributes involved, used to refer to the set of attributes which act or suffer the verb action; Preconditions names, which include the list of names of conditions that constrain the action represented by the verb; Postcondition names, with the list of names of conditions that are true when the verb has already acted; Split verbs, used to enumerate and order the verbs in to which the current verb is split of; Rules name and Fomula are the names of the rules and formula used to carry out actions. Table 9 summarizes a verbs dictionary in the chemicals domain.


TABLE 4
Table of Instance Attribute: Atomic-Weight
 
Instance attribute name Atomic-Weight
 
Value type Mass quantity
Unit of measure AMUa
Precision ­­
Range of values (1, 257)
Default value ­­
Cardinality 1
Inferred from instance attribute Unknown
Inferred from class attribute Unknown
Inferred from constants Unknown
Formula Unknown
To infer Density-at-20-degrees-Celsius
 
a It is the weight of a proton. A gram-atom of an element is the weight of 1/Avogadro's Number of atoms of this element.


TABLE 5
Table of Instance Attribute: Density-At-20-Celsius-Degrees
 
Instance attribute name Density-At-20-Celsius-Degrees
 
Value type Density quantity
Unit of measure Gram/pot(Centimeter, 3)
Precision ­­
Range of values (0, 25)
Default value ­­
Cardinality 1
Inferred from instance attribute Atomic-Weight and Atomic-Volume-At-20-Celsius-Degrees
Inferred from class attributes Unknown
Inferred from constants Unknown
Formula DENSITY = ATOMIC-WEIGHT /ATOMIC-VOLUME-AT-20-CELSIUS-DEGREES
To infer Unknown


TABLE 6
Table of Class Attributes of the Concept Halogens
 
Class attribute name Relation-attribute-
name
Logical relationship Value Unit of measure To infer References
Minimum-Electron-Affinity-
Of-Halogens
Electron-Affinity > 2.5 Electronvolt ­­ ­­
Maximum-Electron-
Affinity-Of-Halogens
Electron-Affinity < 4 Electronvolt ­­ ­­
Minimum-Melting-Point-
Of-Halogens
Electron-Affinity [gte] ­219.62 Degree-Celsius ­­ ­­
Maximums-Melting-Point-
Of-Halogens
Electron-Affinity £ 302 Degree-Celsius ­­ ­­


TABLE 7
Table of Constants in the Domain of Chemicals
 
Constant name Description Value Unit of measure To Infer
Standard-Temperature It is the temperature at which many processes are observed and many measures are taken. 25 Celsius-Degree ­­
Standard-Pressure It is the pressure at which many processes are observed and many measures are taken. 1 Atmosphere ­­


TABLE 8
Table of Instances: Chlorine
 
Instance name Attributes Values
Chlorine Atomic-Number. 17
  Atomic-Volume-At-20-Degrees-Celsius. Unknown
  Atomic-Weight. 35.453
  Boiling-Point. -34.6
  Crystalline-Structure. ­­
  Density-At-20-Degrees-Celsius. Unknown
  Electronegativity. 3.0
  Electron-Affinity. 3.614
  Electron-Structure. 3s23p5
  Group. VIIa
  Half-life. ­­
  Hardness-Scale. ­­
  Ionization-Energy. 12.967
  Melting-Point. -100.98
  Oxidation-States. [1, 3, 5, 7]
  Period. 3
  Radioactivity-Constant. 0
  Resistivity-At-20-Degrees-Celsius. Unknown
  Resistivity-Temperature-Coefficient-per-Degree-Celsius. Unknown
  Semidisintegration-Period. ­­
  Specific-Heat-At-Standard. Unknown
  Symbol. Cl
  Thermal-Conductivity-At-Standard-Temperature. Unknown
  List-Of-Salts ["Common-salt, "Carnallite", "Sylvite"]


FIGURE 12 Attributes classification tree in the domain of chemicals.


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