Page 335 - Practical Design Ships and Floating Structures

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Knowledge presentation is a series of regulation describing objects and phenomena. It is a way of
formalizing and symbolizing knowledge. The progress of artificial intelligence technology provides
various means and methods to present and dispose knowledge. With the development of the
object-oriented technology, it is possible to integrate several single knowledge presentation methods
(such as frame, rule) into a compounded knowledge presentation form. The case of compartment
layout design introduced in this paper ado s the object-oriented knowledge presentation method, and
use frame case to describe object case. Each object-oriented fiame composes of relation slot,
property slot, method slot and rule slot.
Relation slot present the static relationship of object with other objects, the essence of it is describing
object in object. Via the presentation of relation slot, it’s possible to realize the objective of integrated
knowledge utilizing by decomposing the ship compartment layout design knowledge and presenting
multi-knowledge in object.
Property slot describe the static relationship of object. A property slot can describe every feather of
itself via many sides. Valueclass side presents the type of the slot value, inheritance side presents the
inheritance feather of the slot value, and values side record the property value.
Method slot is used to record the method in object. It’s a special dynamic process in frame. The
structure of method includes name, message schema table, local variable definition and method
structure body. Message transferring activates Method, and after the method is activated, the needed
information is selected from the message sent and used by the method process body. Then the method
process body is executed.
Rule slot is used to store generating rule set. Generating rule is grouped into many rule set according
to diverse of their tasks and objective served. Each rule set stores in rule slot as a value, and a frame
can have several rule slots to record different rule subset. Subset can be inherited. The use of rules
depends on rule reasoning machine.
The BNF pattern of Frame knowledge presentation method in object-oriented compound knowledge
presentation form is showed below:

<frame>: :=unit:<fiame name>in<knowledge library name>;
{ memberof: <class frame name> { , <class frame name 1; 1
<slot> {<slot> 1
END unit ;
<slot>::= memberslot I ownslot : <slot name> from<frame name;
valueclass: <slot value class type>;
ililieritance: <inheritance property>;
{ <user-defined side>;< side value>; 1
Values: <slot value;
END slot;
<slot valueclass type: : = integer 1 real I string 1 rules 1 METHODS 1 < class frame name
<inheritance property>: : = override 1 union I METHODS
<frame name: : =<character> { <character> I<number> 1
<slot name>: : =<character> {<character> I<number> 1

2.2 fiesentation of Case in Compartment Layout Design Based on Decomposition
Case is a vital part of ship compartment intelligent layout design knowledge. At the same time, it is
also the most important knowledge component of the Case-Based design mode!. Commonly, a case
of ship compartment layout design composes of three parts: (1) data of compartment layout design
case; (2) knowledge about solving the compartment layout design problem; (3) index of compartment
layout design case. In this a er, the cases are presented by the method of object-oriented hierarchical
structure decomposition.[ ’ r13y using this method, a complex 3D-layout design case can be