[Gzz-commits] gzz/Documentation/misc/hemppah-progradu mastert...

[Hermanni Hyytiälä]

CVSROOT:        /cvsroot/gzz
Module name:    gzz
Changes by:     Hermanni Hyytiälä <address@hidden>      03/02/28 08:18:40

Modified files:
        Documentation/misc/hemppah-progradu: masterthesis.tex 

Log message:
        Xanalogical model

CVSWeb URLs:
http://savannah.gnu.org/cgi-bin/viewcvs/gzz/gzz/Documentation/misc/hemppah-progradu/masterthesis.tex.diff?tr1=1.97&tr2=1.98&r1=text&r2=text

Patches:
Index: gzz/Documentation/misc/hemppah-progradu/masterthesis.tex
diff -u gzz/Documentation/misc/hemppah-progradu/masterthesis.tex:1.97 
gzz/Documentation/misc/hemppah-progradu/masterthesis.tex:1.98
--- gzz/Documentation/misc/hemppah-progradu/masterthesis.tex:1.97       Fri Feb 
28 07:36:15 2003
+++ gzz/Documentation/misc/hemppah-progradu/masterthesis.tex    Fri Feb 28 
08:18:40 2003
@@ -1613,12 +1613,7 @@
 \end{longtable}
 \normalsize
 
-\begin{figure}
-\centering
-\includegraphics[width=14cm, height=12cm]{xanadu_model.eps}
-\caption{Xanalogical nodel}
-\label{fig:xanalogical_model}
-\end{figure}
+
 
 \begin{figure}
 \centering
@@ -1652,8 +1647,8 @@
 \section{Overview}
 
 Fenfire project \cite{fenfireurl} is an effort to build a distributed, 
hyperstructured user 
-interface system. Fenfire is licenced under GNU L-GPL. It's main goal is to 
implement
-xanalogical storage model \cite{ted-xu-model}. Fenfire was formely also an 
implementation 
+interface system. Fenfire is free software and it is licenced under GNU L-GPL. 
Fenfire's main goal 
+is to implement xanalogical storage model \cite{ted-xu-model}. Fenfire was 
formely also an implementation 
 of the ZigZag\texttrademark --structure, which was originally invented 
 by Ted Nelson. Now, however, Fenfire uses Resource Description Framework 
\cite{w3rdfurl}
 for representing internal data structures and their relationships. 
@@ -1677,33 +1672,38 @@
 Xanalogical storage \cite{nelson99xanalogicalneeded} is different kind of 
model for 
 presenting data and relationships between data. While in World Wide Web links 
are
 between \emph{documents}, in xanalogical model links are between individual 
-\emph{characters}.
-
+\emph{characters}. Indeed, each character in xanalogical storage model has a
+permanent, globally unique identifier. For instance, let's consider the 
following
+scenario: ''the character 'D' typed by Janne Kujala on 10/8/97 8:37:18''. In 
this
+example, when character 'D' is is first typed in, xanalogical storage model
+acquires a permanent identifier for that character and retains it when 
character
+is copied to different document. Thus, identifier distinguishes chararacter 
from 
+all similar characters typed in independently\footnote{Xanalogical storage 
model
+is not limited to text. It can support arbitrary data, e.g., pixels of picture 
or 
+frames of video.}. The connectivity in xanalogical storage model between data 
content 
+is more substantial than in other models; a link is shown between any two data 
contents 
+containing a specific \emph{fluid media unit} (e.g., a character) that the 
link connects.
+In practice, however, xanalogical storage model uses \emph{spans}, ranges of 
consecutive
+fluid media units, to handle storage operations. This is done for better 
performance as
+doing expensive operations for \emph{every} fluid media unit is not efficient.
+
+\emph{Enfilade} can be considered as a ''virtual file'' (or part of one), 
which is a list
+of fluid media contents. In xanalogical storage model, links between content 
are external 
+and bidirectional. Xanadu link is an \emph{association} of two enfilades, such 
as an 
+annotation to a specific part of a another document. Transclusion is an 
inclusion in an 
+enfilade of contents already used in another enfilade, i.e. current fluid 
media is copied into 
+different data contents. By using this mechanism, system implementing 
xanalogical model
+is able to show all data content that share same fluid media with current data 
content
+(e.g., all documents containing current document's text). Figure 
\ref{fig:xanalogical_model}
+illustrates xanalogical model.
 
 
-4.1. Xanalocical model (some parts from our article, modify)
-Xanalocical model [cite] is a simple, but rather different model for 
representing content. 
-Project Xanadu [cite] has been a pioneer implementing xanalogical model. In 
xanalocical model
-links are not between documents, but individual characters.
-For instance, when a character is first typed in xanalogical, it acquires a 
permanent ID
-("the character 'D' typed by Janne Kujala on 10/8/97 8:37:18"),
-which it retains when copied to a different document, distinguishing
-it from all similar characters typed in independently.
-A link is shown between any two documents containing the characters
-that the link connects. Xanalogical links are external and bidirectional.
-
-In addition to content links, xanalogical storage keeps an index of
-transclusions: identical characters copied into different documents.
-Through this mechanism, the system can show to the user all documents
-that share text with the current document.
-
-    * Enfilade: a list of fluid media contents, a "virtual file" or part of one
-    * Transclusion: the inclusion in an enfilade of contents already used in 
another enfilade
-    * Xanadu link: an association of two enfilades, such as an annotation to a 
part of a document
-    * pdf files are stored in image blocks
-    * Documents can be created by listing new content or transcluding existing 
content in an enfilade.
-    * Annotations can be entered as new content and Xanadu-linked to a part of 
document.
-
+\begin{figure}
+\centering
+\includegraphics[width=14cm, height=12cm]{xanadu_model.eps}
+\caption{Xanalogical nodel}
+\label{fig:xanalogical_model}
+\end{figure}
 
 
 \section{Storm}