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An approach for e-doc using XML technology
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A technical e-doc application has been developed in a prospective approach
for a sub-system being part of a global military program. To reduce the global
possession cost of the technical users documentation of this program, whose
100 000 pages and 10 000 illustrations will have to be maintained for more
than 25 years, it was decided to give up costly paper standards. The aim of
the prototype now developed is first to validate the e-doc production automated
process, and secondly to propose the users an ergonomic e-doc application,
he could react on to improve the specifications of the future global e-doc
system.
This paper aims at presenting this SGML/CGM project for technical e-doc
in the context of the functional needs and the immediate benefits XML and
its companion standards brought to it.
The scope of the project is to cover illustrated parts catalog, descriptive,
maintenance documentation, including all needed sets of associated logistics
and technical data (task duration and level, spares, manufacturer).
The project lead to the development of an e-doc database being built
from the input technical data linked to the documentation items. The e-doc
database uses a lightweight database engine. It is calculated from input data
and linked to documents using an SGML-aware transformation engine.
The past
The users documentation of the last military launcher, done between
1980 and 1995, was very heterogeneous in its presentation and production process.
It was mostly realized according to AIR 106 paper standard. A small part complies
with the ESM 56/60 (IT 88805) standard and was integrated in a e-consultation
system. Lastly, the software description documentation was an e-doc based
on information from the software production tools. The "paper process" was
based on :
- 1. The analysis of all the paper documentation made during the whole
development of the product (specifications, definition, maintenance manual,
user's manual …) by the many different manufacturers. This documentation
used to be very different from a manufacturer to another.
- 2. The partial or total rewriting of the documentation, following the
imposed standards,
- 3. The illustrations realization, on e-media or on papers,
- 4. The realization of documentation mock-ups,
- 5. The subcontracting of data acquisition, editing and distribution.
The process is illustrated in
Figure 1.

Figure 1
. Process formerly applied
As known by everybody, this process had major drawbacks :
- Important paper volumes (several m3 for the whole weapon system),
- Different consultation means,
- At least 2 different data acquisition,
- Complex realization process,
- Information duplication in different tomes,
- Long realization and updating cycles,
- Realization at the very last time, when all the development information
is over,
- Specific tools use, which generated important tools logistic support
costs.
The goal
The main challenge for M51 user's documentation is to divide its realization
cost by two. In order to do so, some solutions are considered :
- Maintenance policy simplification,
- Number of pages reduction (re-use of some parts, description manual
simplification, less LR1-Level of Repair- and LR2 operations …),
- Use of structured and modular e-documentation,
- LSA (Logistic Support Analysis) and Documentation process integration.
The structured and modular documentation and associated realization
process is already used or will be soon used by most of the military projects
and by most of the involved manufacturers so as to reduce the preceding drawbacks.
The new process leads to an upstream movement of some tasks. As a matter
of fact, the manufacturer is now totally responsible for the user's documentation
dealing with the product he provides. The splitting and organization of tasks
has to be re-thought. The tools and ability needed by each actor of the process
also mostly change.
The expected process is illustrated in
Figure 2.

Figure 2
. Expected process
The important expected savings in realization and maintenance costs
are due to the following advantages of the process:
- No paper volumes (the user only prints what he needs, if he wants),
- Only one data acquisition,
- Easy and fast updating,
- Longer documentation realization period,
- Homogeneous and ergonomic consultation means,
- Use of ISO norms and of standards,
- Use of ready-to-use commercial or public domain tools.
The prototype
Overview
A prototype was made in 1999 and 2000 in order to :
- Test the e-documentation realization process :
- Process automation,
- No data modification from the data acquisition by the manufacturer,
to the delivery of the e-doc to the system users,
- Test the users' reactions to e-doc.
The so made e-documentation deals with the description manual, maintenance
manual and illustrated parts catalog of a 65 tons handling device.
The global process that was held, is illustrated in
Figure 3.

Figure 3
. Global process
The experience we already have by this prototype can be detailed as
follows :
- We need tools which are ˙:
- simple and ergonomic,
- cheap and easy to distribute,
- integrated (LSA records, Data modules, Interactive Illustrations,
edition),
- with on line help and with writers guidelines,
- We have to precisely organize the process from the bid to the product
(and its e-doc) approval,
- writing comprehensible and simple, technical and contractual specifications,
- preparing a bidding evaluation grid,
- making tools formation modules,
- identifying and training potential subcontractors, able to realize
LSA and e-doc,
- training AML engineers responsible for the products realization,
- organizing and automating the validation of data,
- …
- We still need standards dealing with the logistic support and users'
documentation data organization, which can be easily, industrially
and cheaply implemented.
The following sections focuses on development of the e-doc data preparation
and consultation software, stressing out (on the technical side of things)
the benefits of using neutral industrial encoding formats.
The overall data preparation and consultation software architecture
is illustrated in
Figure 4.

Figure 4
. Data preparation and consultation software
architecture
Neutral format input data
At the beginning of the process are the data. The documentation items
are stored in a production system and encoded in state-of-the-art neutral
format : SGML for textual data, TIFF, CGM, JPEG for graphical data. Technical
data, LSA related, are stored in a production DBMS and exchanged as raw ASCII
files.
In the pre-XML life, there was numerous and certainly good arguments
to justify encoding of document data into neutral standardized format e.g.
SGML for text. However, the general feeling was that the gap between rough
data and its consumption by end-user, through a published form, was a kind
of technical challenge.
Knowing this, a lot of potential SGML users did not dare to move forward
into a fully structured text approach. Now with XML, we benefit from core
tools, free and integrated in the most common desktop environments. Moreover,
the ability to transport and manage well-formed documents avoids to oversize
the consultation part of systems with DTD-aware software.
In this given context, one key choice is to transform SGML documentation
modules input their well-formed XML equivalent.
Data preparation
The data preparation is a batch process which takes input data set and
transforms it into a human-consumable form. The data input is read from a
flat file system without any direct connection to the production system. The
whole data preparation is written using a SGML/XML-aware scripting engine.
SGML documents are transformed into XML documents enriched with technical
data required for interactive consultation. Transforming is done without any
major structural modification, other than adding technical data and refining
the granularity of information. Typically front-matter parts are extracted
from master TOC to get an independent modules. Thanks to strong SGML/XML filiation,
this is a straightforward process. Graphical files are linked to technical
data in order to provide interactive graphic navigation through CGM vector
files.
From a template database file, a lightweight database is populated using
the ODBC connectivity of the SGML/XML-aware scripting engine. This database
holds :
- Product top-down breakdown,
- Meta-data associated to each product node,
- Links to XML transformed modules,
- Links to graphical modules with reference to parts illustrated on
each graphic,
- LSA data as list of suppliers, spare parts, consumable...
The mapping between input and output structures is described in an XML
file. This makes parsing of this configuration file easier. The data preparation
is a fully automated batch process. It checks global consistency of data,
including SGML instances validity. In case of success, it just produces an
output database ready for consultation.
Consultation software
The consultation software is designed as a windows multiple document
interface application, providing support for the various manuals and LSA data
list.
The backbone of the e-doc application is an interactive illustrated
parts catalog based on product top-down breakdown, it uses a CGM hotspot-activated
viewer synchronized with a treeview fed by technical data. It appears to be
a major trend for coming years that technical e-doc should be based on interactive
illustration. Additional specific printing features have been developed since
the desired paper output model is nomenclature oriented.
The
Figure 5 is an hardcopy of the illustrated
part catalog.

Figure 5
. Illustrated part catalog on screen
The e-doc application makes intensive use of standardized XML-aware
Internet viewing technology embedded into a customized application. Due to
the requirement of managing a multiple windows interface and special search
requirements, the decision has been made not to implement a simple browser-based
application.
Maintenance and descriptive manuals are viewed on-the-fly as XML fragments
using XSLT as the transformation process to a presentational HTML structure
and CSS as a way to refine the dressing of this structure. In order to provide
a fully interactive dynamic page, what is actually generated as output is
more than simple HTML, but a combination of DHTML/DOM and Javascript. This
is used for expandable TOCs and for module contents as well. The default layout
and formatting semantics model is the HTML one (autowrapping and scroll mode),
doubtless the most appropriate for screen reading. CSS media-sensitive features
allow to generate different presentational structure when output is paper.
The
Figure 6 is an hardcopy of the maintenance
manual window.

Figure 6
. Maintenance manual on screen
The links between different parts of the documentation are activated
when useful, taking advantage of underlying strength beyond SGML/XML structuring
:
- Between illustrated part catalog and maintenance manual,
- Between documents and LSA data,
- Between illustrated part catalog and LSA data,
- Intra and inter manuals.
The application is also able to search and retrieve documents or articles
based on keyword search, and to manage bookmarks, users annotations and consultation
log information.
Prospective
As a conclusion, the wide-spread adoption of Internet technologies and
XML has brought tools from the mass market that are potentially unlimited
in term of presentation. These tools leverage the potential of structured
textual data to build truly interactive e-doc. Today we can develop more efficient
and cheaper e-doc than five years ago.
At the time when the technical choices were made (summer 1999), a number
of XML companion standards were still in an uncertain situation. Knowing the
huge success of XML, we were confident that things would evolve in a positive
way and reach broader adoption in tools. This occurred as expected.
As these lines are written, a number of evolutions are still in progress
to streamline the e-doc production :
- Full implementation of XSLT at the level of W3C recommendation in
desktop tools,
- Full implementation of CSS1-2 in desktop tools,
- Development of SVG, and associated viewing engines, as fully XML-compliant
and embedded 2D graphical vector format,
- Development of XSL FOs for sophisticated printing features,
- Development of XML-native lightweight database engine using XQL
or other XML-aware request syntax.
If it is currently heard that XML development is driven by e-commerce
for its larger audience, it remains extremely pertinent to use it for technical
e-doc. Furthermore, it benefits to industries which have already invested
in SGML.
The future
By 2003, we have to specify, realize and implement a complete Logistic
Information System, able to help acquisition, checking, management and modification
of the following data :
- Logistic support analysis data,
- Data modules for user's manual, maintenance manual, description
manual,
- Illustrations for all manuals and for illustrated parts catalogue,
- Publication and delivery data,
- Consultation data.
This LIS also have to implement all needed interfaces, such as with
PDM, CAD…
We expect that XML and all associated technology and tools will greatly
help us to achieve this end.
Acknowledgements
We thank very much :
- All the AML team (Jean-Yves, Christian, Alain, Serge, Claude, Henry
…)
- All the ES project team (Stéphane, Thomas, Solène,
Isabelle)
for their active and efficient involvement in this project.