Friday, February 17, 2017

Updates and NUDS XSD Schema

At long last, I have made significant updates to the Numismatic Description Schema (NUDS) XSD file, which has been hosted on Github for quite some time. From the documentation:

The Numismatic Description Schema is a codified XML schema based on numismatic database fields proposed by Sebastian Heath and Andrew Meadows. These fields, called the Numismatic Description Standard, are detailed at http://www.greekcoinage.org/nuds.html, and were originally published on Nomisma.org. The NUDS XML schema is based on this field list and Ethan Gruber's preliminary work mapping coins to Encoded Archival Description, which was detailed in a 2009 Computer Applications in Archaeology paper, "Encoded Archival Description for Numismatic Collections". It is also influenced by the structure of TEI and EAC-CPF, common standards in the Digital Humanities, library, and archival domains. Ideally, a NUDS record should implement XLink attributes to integrate URIs from external Linked Open Data vocabulary systems, such as concepts defined on Nomisma.org itself.

The updates have been undertaken to make NUDS more flexible for the encoding of seals for a project overseen by Charlotte Roueche at King's College London. These improvements include documenting every element and attribute in the schema, and enabling the namespacing of EpiDoc TEI into the nuds:description for enhanced prose markup and the nuds:legend for more sophisticated annotation of inscriptions. The Numishare codebase will be extended to include EpiDoc XSLT templates for rendering TEI in the applicable NUDS elements.

Since its inception in summer 2011, the NUDS XML namespace has pointed to http://nomisma.org/nuds, which was never a dereferenceable page. It is now--it is the XSD schema transformed through XSLT into an HTML tag library with usage examples (I am still working on adding these examples).

The XSD is available directly at http://nomisma.org/nuds.xsd, which can be considered a stable URL, and may be used for validation of XML files.

Tuesday, February 14, 2017

Roman coins from the Metropolitan Museum of Art enter Nomisma

The Met Museum is the latest institution to be integrated into the Linked Ancient World Data Initiative, following their major announcement last week concerning the release of more than 375,000 images into the public domain and the publication of a dump of their data into a massive CSV file.

Aureus of Julius Caesar in CRRO

I almost immediately got to work on parsing this CSV in order to link their coins to Online Coins of the Roman Empire and Coinage of the Roman Republic Online, but found that the dumps did not include full type references to RIC or RRC, nor did I find a clear way of extracting images from the database for re-use. With many thanks to curator Christopher Lightfoot for providing a concordance between the Met's coins and reference numbers and Ben Rasmusen for some tips on interacting with the Met's not-yet-published 'additionalImages' web service, I wrote a simple PHP script to generate Nomisma-compliant RDF. I have just ingested this into Nomisma's SPARQL endpoint. About 60 coins have been positively linked to URIs in CRRO and OCRE. Furthermore, these coins will be integrated into the Pelagios Project by means of the Nomisma->Pelagios export feature.

You can see examples of three aurei of Julius Caesar (RRC 466/1) from the Met along with examples of the same type from six other museums. You can get a concordance list of Met and coin type URIs back out of the SPARQL endpoint with the following query: https://gist.github.com/ewg118/f9c8bae782fdc841af6c7aca782ef06d.

Monday, February 13, 2017

OCRE surpasses 100,000 physical specimens, including Polish coin finds, and more

We have several additional news events to report:

  1. We have finally published the Roman coins from the American Numismatic Society with references to RIC 9 to Online Coins of the Roman Empire. This has brought us to a milestone 100,000 physical specimens linked to about 42,000 imperial types spanning five centuries from Augustus to Zeno.
  2. We have reprocessed our data from RIC 4 in order to represent the type-subtype hierarchy within that volume more accurately. Some data errors have been fixed due PHP processing glitches or typos in deity names.
  3. More than 7,200 coins in the Finds of Roman Coins in Poland project (part of the European Coin Find Network umbrella) have been ingested into Nomisma.org for query and visualization. Of these coins, 23 are linked to URIs defined by OCRE.
  4. I discovered a glitch in my script for mapping references to Price (1991) to IDs in Pella, and now about 500 coins in the ANS of Philip III and Lysimachus have been added into Pella.
  5. Berlin has added an export for Macedonian coins found in the excavations of Priene, and two have been added into Pella.


OCRE has eclipsed 100,000 coins, but our total between this, CRRO, Pella, and AoD stands at about 153,000.

Wednesday, February 8, 2017

Harvard Art Museums coins reprocessed, added as IIIF contributors

Harvard Art Museums is one of three contributors of coins to Nomisma.org, providing data and images for all three of our major coin type projects: OCRE, CRRO, and Pella. They are also one of our few partners providing images according to IIIF image API specifications. Following the application of the Europeana Data Model specs for IIIF integration for Rutgers' entry into Nomisma.org, I have updated my script for harvesting numismatic content from Harvard to include IIIF manifest metadata.

Accordingly, I made some minor code changes in Numishare to handle IIIF manifests for combined images (obverse and reverse in the same image file). You can see an example of a Philip III coin from Harvard here.

The Harvard Art Museums' coins in Pella will be the perfect test cases for applying Open Annotation + IIIF for annotating symbols and monograms defined by URIs in the Online Greek Corpus project.

Thursday, January 5, 2017

Rutgers University's Badian Collection added to CRRO + IIIF support

Rutgers University's Badian Collection is the newest contributor to Nomisma.org, providing 682 Roman Republican coins to Coinage of the Roman Republic Online. The Rutgers University Libraries are the publishers of these data, and by means of their Fedora repository software and IIIF APIs, I was able to write a PHP script to harvest their MODS/XML (and other miscellaneous metadata records) and generate Nomisma-compliant RDF.

Following recent updates to Kerameikos.org's IIIF integration, I implemented the same modifications to Nomisma's RDF model: data objects for describing IIIF images and services according to Europeana Data Model specifications. The Nomisma documentation has been updated accordingly: http://nomisma.org/documentation/contribute#iiif.

The user interfaces in Numishare (and therefore CRRO) have been updated to optionally query for the dcterms:isReferencedBy property associated with examples of coin types. I have implemented the IIIF plugin for Leaflet to display the zoomable image in a Fancybox popup window. See the Rutgers coin on http://numismatics.org/crro/id/rrc-474.2b, for example. Several other partners have implemented IIIF, and I will reprocess these collections to add service metadata into their RDF dumps. It is on the ANS agenda for 2017 to deploy our own IIIF image server. In the coming years, it is my aim to implement an image annotation system that will make it easier to identify and tag symbols and iconographic attributes on coinage, which will facilitate a wider range of art historical or political/economic analyses of coins.

Tuesday, December 6, 2016

University of Heidelberg joins Nomisma

The Centre for Ancient Studies of Heidelberg University is the newest member of the Nomisma.org consortium. The Seminar für Alte Geschichte und Epigraphik of Heidelberg University together with the Institut Klassische Archäologie holds a collection of more than 4,000 Greek and Roman coins. The collection dates back to Georg Friedrich Kreutzer (1771-1858) and grew with later purchases and donations. From the beginning, the collection was conceived to be used for teaching purposes, highlighting the history of coinage from its origins in ancient Greece down to Late Antiquity. The collection is available online at http://pecunia.zaw.uni-heidelberg.de/ikmk/. The university presently contributes about two dozen items to OCRE and CRRO (see RIC Nero 2, for example),  but this contribution will grow as the collection continues to be digitally cataloged.

Tuesday, November 1, 2016

Distribution Analysis of Portraits and Deities

Building on recent advancements in distribution visualizations I rolled into production on Nomisma.org last month, I have extended the complexity of these visualizations to include portraits and deities both as distribution categories and parameters for generating subsets of results from the Nomisma SPARQL endpoint. Deities, in particular, required some extra work. While we have incorporated URIs from the British Museum thesaurus for deities into our data throughout ANS projects, there had been no accompanying triples for these URIs to provide human-readable labels. I wrote a simple script to extract labels from the British Museum SPARQL endpoint in order to generate a fairly simple SKOS-based taxonomy for the entities, which I then uploaded into Nomisma's endpoint. You yourself can download this small RDF dataset from http://nomisma.org/datasets.

Distribution of mints for Augustan coin types of Victory vs. Mars

This required rewriting the underlying XSLT templates in the XPL for generating the XML model (which would be serialized into the JSON view required by d3plus, a chart extension for d3js). The previous XSLT stylesheet stored a generic SPARQL query as text, which had bits and pieces replaced with variables passed in via HTTP request parameters. This worked well enough when querying predicates stored directly within the coin type data object. However, portraits and deities are expressed at a deeper level--within the triples describing the obverse or reverse of the coin. Thus, a query for coin types depicting Agrippina the Younger is as follows:

?s a nmo:TypeSeriesItem ;
  nmo:hasObverse ?obv ;
  nmo:hasReverse ?rev .
{?obv nmo:hasPortrait nm:agrippina_ii}
UNION {?rev nmo:hasPortrait nm:agrippina_ii}

As a result, the simple textual search-and-replace technique for constructing the SPARQL query was reconceived as a data object (represented as XML within an XSLT variable) generated by HTTP request parameters. Each triple XML element contains a subject, predicate, and object attribute. Union and optional queries are contained within relevant XML tags.

<triple s="?coinType" p="nmo:hasObverse" o="?obv"/>
<triple s="?coinType" p="nmo:hasReverse" o="?rev"/>
<union>
    <triple s="?obv" p="nmo:hasPortrait" o="{$object}"/>
    <triple s="?rev" p="nmo:hasPortrait" o="{$object}"/>
 </union>

Where the $object is the object in the "compare" or "filter" request parameter (in this case, nm:agrippina_ii). This XML expression of a SPARQL query is then transformed via XSLT templates into the plain text which is then used to GET the response from the endpoint. I have posted this XSLT stylesheet to gist.

Enhancing geographic distribution

I added one little, but very useful tweak. As previously discussed, the data for any visualization can be downloaded as a CSV file. I enhanced this CSV file by including the entity URIs, but, more importantly, when the distribution category is set to "Mint", the underlying SPARQL query will extract the latitude and longitude if available. As a result, you can drop the CSV directly into Google Fusion Tables to generate a map or import it into GIS software (like QGIS), and using the count or percentage column, adjust the size or coloration for a more accurate, graduated visualization (like below).

Distribution of Augustan issues depicting Victory