Conversely, to enable automatic application generation, HDM has been extended with a built-in navigation semantics, expressed by navigation modes and collection visibility rules, and with an original presentation model, inspired to the notion of bidimensional schedule of HyTime [Derose and Durand 1994].
In the HyTime hypermedia standard, navigation is addressed by focusing on location, i.e., on flexible constructs for defining the anchors of links at various level of granularity.
In converting documents between hypermedia systems, you typically have to convert more than the logical format, which might be represented in an intermediate markup language such as HyTime
. Each hypermedia system will support its own preferred media formats.
' the hypermedia/time-based document structuring language.
In the description of his speech, "Implementing a HyTime
system in a research environment." SGML '92 Conference Program.
By using links, a full set of ideas regarding addressing schemes can be incorporated following the intentions of the HyTime
One of the design criteria for HyTime
is that it be Dexter-compliant.
The proposed standard "HyTime
" Hypermedia/Time-based Document Structuring Language (ISO/IEC Draft International Standard (DIS) 10744), built on the Standard Generalized Markup Language (SGML; ISO/IEC International Standards (IS) 8879-1986), is designed to make all this possible.
Structured document technology is used to avoid reformatting costs when the time comes to convert its paper maintenance manuals to on-line form, to be delivered as "Interactive Electronic Technical Manuals" to military technicians on "Portable Maintenance Aid" terminals (see the sidebar, "HyTime
and the Content Data Model" and ).
One important effort deals with applying the Standard Generalized Markup Language (SGML), ISO 8879, as discussed in an upcoming report about HyTime
review: Standard for hypermedia/time-based document interchange.
There are too many current or proposed standards (such as ODA and HyTime
), too many people with commercial interests in particular representation formats (such as CDA and PostScript), and simply too much technical uncertainty about the requirements of such formats, for there to be much hope of seeing a standard settled on any time soon.