Space-time metadata provides an opportunity for digital humanities researchers to incorporate the contents of their work into historical visualizations like timelines and mappings. This section explains the rationale behind our metadata design and gives an example of how it could be applied.
For over twenty years the Text Encoding Initiative (TEI) has managed and developed a set of encoding guidelines for the digital representation of humanities, social science, and linguistics texts. Using the Extensible Markup Language (XML) as its backbone, TEI is the generally accepted encoding model for the digital humanities. History focused, space-time metadata needs to be compatible with TEI. We used the following criteria to design our own custom TEI-XML element.
At times, TEI can be pretty intense, especially if you are adding multiple child elements and attributes. Ideally, our model should have only one element with the bare minimum of attributes
Wherever possible, no abbreviations, no shortcuts. This probably means long element and attribute names, but users with no metadata experience should be able to look at the markup and be able deduce what it represents.
Attributes of the element should: follow TEI's customization guidelines; record latitude, longitude and altitude; emphasize ranges over exact points; be ISO 6709 and ISO 8601 compliant; and indicate what locale the space time data is relative to, for instance "earth".
Interoperability is the overriding principle. if we use something proprietary, there is a risk of restricted accessibility which then leads to decreased interoperability.
After multiple iterations, we came up with the following element.
Text of the historical event.
<historyEvent relative="earth" timeRange="1943-01-12T00:00:00/1943-01-12T23:59:59" spaceDiagonal="-23.4094+150.4739+37+11.3/-23.3341+150.5592+37+11.3/">
<head>Jan 12, 1943 - Rockhampton</head>
<p>Went on 3 hour alert this afternoon and as rumor has it, we are to leave for New Guinea in two days. Busy Packing all personal and Co. gear.</p> </historyEvent>
Currently, we have begun implementation and testing of this element using the John Slocum War Diaries Project.