Situation Metaphor (Contd) 



 Situation Space 




Notations Used in Situation Space


    


  • SS-> defines the situation space
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  • S',S"-> define two distinct situations
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then  
    S' = S" 
      iff 


    ( L' = L"  ^  T' = T"  ^  A' = A"  ^  F' = F" ) 
    

where " ^ " is the symbol representing "logical and" operation.



  •  if " * " denotes the concatenation between two situations then


    S' *  S" belongs to SS   
    

if | L' - L" | < e  for e > 0    and    T' + T" is a continuous period

| L' - L" | represents the geographic distance between the Locations L',L"
 
T' + T" is a single segment on the time line

thus if  S' * S" belongs to SS we can call 


     S" is the sucessor situation of S' 
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  •  if ID(S')=NULL then  S' is defined as a null situation
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  •  Related Ness property between two Non-null situations in SS

 
     R(S',S") = | ID(S')  î  ID(S") |  +  k 
    
 

where î represents the set intersection and the value of k depends on
the content analysis of the two sets.



  •  If R(S',S") > h  for a given value of h,then S',S" are said to be 
strongly related situations 
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  •  If R(S',S") >h and R(S",S"') > h but R(S',S"') < h then 
R(S',S"') are said to be weakly related for a given threshold h
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  •  The Navigation Function for a particular situation is given by

    F(S',d)={Sd1,Sd2,Sd3,....Sdn }
    
such that for all k=d1,d2,d3,...dn Sk is in SS and R(Sk,S') > h

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