Wednesday, December 20, 2017

Seleucid Coins Online launches

Another major piece of the NEH-funded Hellenistic Royal Coinage has been put into place. More than 3,000 Seleucid coin types from Lorber, Houghton, and Hoover's Seleucid Coins, Part 1 (expect Part 2 in 2018) have been published to Seleucid Coins Online. Users of ANS coin type corpora will be familiar with the layout and functionality, as this project is also published in Numishare, the same as OCRE, CRRO, and PELLA. Using semantic modeling inherent to Nomisma, dynasties and political entities to which rulers belong are now available as facet fields.



The first contributors of coinage to this project are the University of Münster (Archäologisches Museum der Westfälischen Wilhelms-Universität), Harvard Art Museums, the Berlin Münzkabinett, and the ANS's own collection of nearly 1,700 Seleucid Coins. We expect to add coinage from other partners, such as the British Museum and Fralin Museum at the University of Virginia shortly. Our colleagues Karsten Dahmen at Berlin and Frédérique Duyrat are working to translate type descriptions, and we will activate French and German in SCO early in 2018. The ANS and Harvard are both contributing images according to the IIIF specification.




Page for http://numismatics.org/sco/id/sc.2.21
With the ingestion of typological metadata as RDF into the Nomisma.org SPARQL endpoint, it is now possible to conduct broader geographic and statistical distribution and metrical analyses with Nomisma's own set of tools (e.g., to compare the weight of Seleucid tetradrachms with those of Alexander). The type data and associated physical specimens also provide further research context for individual concepts defined on Nomisma. For example, the Nomisma page for Seleucus II will now display a map displaying the distribution of mints and findspots for the ruler, as well as a sample listing of related coin types (with photograph of coins linked to these types).
All of the data are available for free and open reuse.

Wednesday, December 6, 2017

More than 20,000 Roman Republican coins from the BnF added to CRRO

In a watershed moment for Roman Republican numismatics, 20,237 coins with high-resolution IIIF images from the Bibliothèque nationale de France have been incorporated into the Nomisma.org SPARQL endpoint, and are therefore available in Coinage of the Roman Republic Online. This nearly doubles the coverage of Republican coinage--there had previously been about 26,000 coins available through CRRO from 18 museums or archaeological databases (like the Portable Antiquities Scheme).

RRC 452/3


The addition of IIIF images for these coins greatly increases the scope of dynamic, SPARQL-generated IIIF manifests for coin types, such as this one from RRC 335/1a.

Florence Codine, from the BnF Coins and Medals department, provided a spreadsheet dump of these coins, which have been meticulously cataloged with CRRO URIs. I updated the PHP script I wrote for the integration of the BnF's coins of Alexander the Great into Pella. This script iterates through all of the ARKs in the CSV and queries the Gallica OAI-PMH endpoint to extract further metadata available in the OAI Dublin Core. This script then outputs RDF/XML conforming to the Nomisma ontology and data model, with the IIIF extension following the Europeana Data Model specification.

Some Basic Stats

  • 2,295 total RRC types in CRRO
  • 2,119 types are connected to at least 1 physical type (92% coverage)
  • 2,105 types connected to at least 1 physical type that has been photographed (91%) (SPARQL query)
  • 1,791 types are connected to BnF coins specifically (78% coverage for just one collection!)
  • RRC 340/1 has the largest photographic coverage with 1,878 coins! [I am going to need to introduce pagination for SPARQL results on coin type pages]
  • 63 types have more than 100 photographed specimens
  • 966 types have more than 10 photographed specimens (42%)

Here's a CSV output of all types + the total image count per type: [download]

Tuesday, November 7, 2017

Numishare supports OpenRefine reconciliation APIs for OCRE, PELLA, and CRRO

After building a reconciliation service for Nomisma concepts, I began working on applying the same methodologies to creating an OpenRefine reconciliation API for coin type corpora projects published in the Numishare platform. The API has been extended to support suggestions for properties. These properties are facet/string (exact match) or text (keyword anywhere) fields for mints, rulers, denominations, etc. that have been indexed into Apache Solr. It may be possible to extend this property list to dates, legends, or other indexed fields.

Property suggestion API is derived from available Solr facet fields

Test Case: University of Graz Roman imperial coins

I received a spreadsheet of about 2,000 Roman imperial coins with RIC numbers and emperors from Elisabeth Steiner at the University of Graz. I performed some cleanup of the RIC numbers and normalized the emperor list to English preferred labels via the Nomisma OpenRefine reconciliation service (more details below). About half of the coins normalized to OCRE IDs on the first pass (which took 45 seconds), but the majority of non-matches fell into two categories: RIC numbers that had been split by OCRE into separate URIs due to differences in denomination and RIC 6-8 volumes, where the numbering restarted based on mint rather than ruler. To ameliorate these issues, I got an updated spreadsheet that contained columns for mint and denomination.

Filter for uncertain attributions, 'od.'

My workflow was as follows:


Tuesday, October 31, 2017

ANS web projects, IIIF deployed on new server

In other big news today with the consolidation of Nomisma and ANS digital projects on numismatics.org onto the same dedicated server (which is much more powerful than the separate cloud servers each domain previously ran on), our IIIF image server (Loris) and presentation APIs are now running in production. IIIF functionality extends beyond simple zoom functionality and manifests for single objects in our own collection (e.g., http://numismatics.org/collection/1944.100.39026), but an entirely new array of features, some of which have been described in previous posts:

  • There are now 160,000 photographed objects in the ANS collection, the high res photos of which are available through IIIF. Of these, more than 55,000 are Greek and Roman coins linked to types defined in OCRE, CRRO, and PELLA. Like our other partners that publish IIIF, the zoomable images are available on the coin type landing page, but the ANS adds tremendous coverage in these domains. See dozens of our coins linked to Price 4.
  • Manifests for coin types are generated dynamically by a combination of NUDS typological metadata + SPARQL query results for associated physical specimens with IIIF service metadata. The manifest is linked at the top of the page, along with a link to view the manifest. These sorts of manifests are the jumping-off point for annotating symbols and monograms on coins.
  • The ANS Archives support IIIF through TEI (digitized coin hoard notebooks), EAD, and MODS resources (photographs). Photographs linked to ancient places defined in Pleiades can be ingested into Pelagios. More here: http://eaditor.blogspot.com/2017/10/eaditor-now-supports-ead-and-mods-to.html. The Newell notebooks are so far the only digital resources featuring annotations, so far.
  • Rainer Simon is reindexing the ANS coins linked to ancient places via Nomisma->Pleiades concordances into Peripleo. These extend beyond the 55,000 Greco-Roman coins linked to OCRE, CRRO, and PELLA to include all ancient coins linked to Nomisma IDs for mints. See https://twitter.com/aboutgeo/status/925292397986279425. Of the 140,000 coins in MANTIS linked to Pleiades places, about 83,000 have been photographed/provide IIIF service metadata to Pelagios.https://twitter.com/aboutgeo/status/925292397986279425

Nomisma launches OpenRefine reconciliation service

I recently received a spreadsheet of Classical and Archaic Greek coin hoard data, atomized and parsed for content in the Inventory of Greek Coin Hoard textual descriptions. I loaded this spreadsheet up into Open Refine in order to break it down further in order to separate the Authority column into separate columns for mints, regions, and rulers, parse uncertain attributions (looking for question marks), separate the numeric count of coins from denomination abbreviations, etc. The Authority column itself contained mostly mints, all of which are represented by concepts defined on Nomisma.org. The easiest way to reconcile this list would be to run against an OpenRefine reconciliation API, which did not exist--so I built one between Friday and Monday.

The new service is now listed among the Nomisma APIs, available at http://nomisma.org/apis/reconcile.



The API does not support every possible optional service yet, but it supports the most useful one for normalizing data to Nomisma concepts. Here's what it does do:

  • The main reconciliation service, returning the basic service JSON when there are no query parameters. Both the 'query' and 'queries' HTTP parameters are supported. These query parameters are parsed into one or more Solr queries to yield a response.
  • The Preview API, for displaying a little HTML popup when hovering the mouse over a reconciled candidate (a simple serialization from the concept RDF/XML into HTML).
  • The Entity Suggest API, which allows a user to type in a new term, yielded an autosuggest response (this is also Solr serialized into JSON). The suggest flyout is also supported, which is a serialization of the concept RDF/XML into a tiny JSON snippet to be displayed when hovering over the autosuggested term.

These are the most vital services, which enabled me to normalize about 3,500 of 4,000 lines of the CSV to existing Nomisma mints, regions, and rulers. About half remaining 500 are multiple mints of the same place name that need to verified on a case by case basis (by checking the IGCH or Coin Hoards record). After that, the only non-reconciled values remaining are rulers that do not have Nomisma IDs yet. We can extract a facet list of these values and generate the Nomisma IDs, and then reconcile the list.

I spent about two days working on these APIs, and then did almost 90% of the matching in five minutes.


Wednesday, October 4, 2017

University of Graz joins Nomisma partner consortium

The Institute of Ancient History and Classical Antiquities at the University of Graz houses a collection of nearly 4000 antique coins. Nearly 300 of these are Roman Republican coins identified with Michael Crawford's Roman Republican Coinage numbers. Working with Elisabeth Steiner, who is responsible for the digital archaeological collections, we were able to link these to URIs for RRC types defined in Coinage of the Roman Republic Online and ingest them into the Nomisma.org SPARQL endpoint. Additionally, the photos of the coins are available through IIIF services, and the coin metadata (canonically stored as TEI files in a Fedora repository) are transformed dynamically and served as Nomisma-compliant RDF directly from their information system.

There are several thousand Roman imperial coins with Roman Imperial Coinage references, but some work remains in normalizing emperor + RIC numbers to OCRE URIs.

You can see an example of two University of Graz coins linked to RRC 282/1 here.

Wednesday, September 13, 2017

SPARQL-derived IIIF Manifests for Coin Types

Building on Numishare's new IIIF manifest functionality, I have extended this feature to support the generation of a manifest for the IIIF resources for physical coins associated with coin types. The coin type manifest is generated in much of the same way as other queries for related coins: a SPARQL query, with the exception that the results are restricted only to physical specimens connected to IIIF services, according to the EDM extension.

The query is here: https://gist.github.com/ewg118/d4833fc0f61c17f84c723dcb3a7fe901

The metadata for the manifest are still derived from the typological information within the coin type NUDS document, but each canvas object is transformed from the SPARQL results for each coin.

The challenge here is that different organizations have different standards for packaging their obverse and reverse photographs. Most of our IIIF partners (including the ANS) have a separate image file for both the obverse and reverse, but several (like Harvard Art Museums) have combined the obverse and reverse photos into a single image file. In order to present the most cohesive and intuitive display of the manifest within a IIIF viewer, I opted to represent each coin rather than each image as a canvas (and incorporated collection, identifier, weight, diameter, and axis metadata within the canvas). Therefore, I experimented with generating a canvas as wide as the width of both the obverse and reverse images and placing both images on the same canvas, with the reverse image as a segment with its top left corner aligning with the top right corner of the obverse image. This is done by specifying placement and dimensions of the canvas:

"on": "http://gallica.bnf.fr/ark:/12148/btv1b10323768v#xywh=2646,0,2646,2646"

However, I have found that neither Universal Viewer nor Mirador support this functionality out of the box yet, even though it is valid according to the IIIF Presentation API. It does work in Masahide Kanzaki's IIIF viewer built on OpenSeadragon.



You can see an example of the Price 112 manifest rendered here: http://www.kanzaki.com/works/2016/pub/image-annotator?u=http://app1.numismatics.org/pella/manifest/price.112

IIIF coverage will be expanded significantly across PELLA, OCRE, and CRRO once the new version of Mantis goes live in the next one or two weeks. There is now a link at the top of each coin type page (when applicable) to the IIIF manifest.

Thursday, August 31, 2017

Extending Numishare for IIIF

The American Numismatic Society is in the process of migrating both its own production web applications and Nomisma.org to a central dedicated Rackspace server from the Rackspace cloud. The new server has a lot more resources, which will make our projects more stable and efficient. Furthermore, the extra storage, CPU, and RAM will now make it possible to publish high resolution images through IIIF. All of our high resolution images have been transferred to the new server (over 420GB), and when we flip the switch on the domain names over to the new server, Mantis will now feature high resolution zooming of the obverse and reverse images of about 150,000 objects in its collection. The RDF exports from Mantis for both Nomisma.org and Pelagios will include IIIF service metadata conforming to the Europeana Data Model extension (already detailed in older posts). This means that the high-res coverage of Roman Republican, Imperial, and coinage of Alexander the Great will be increased by 60,000 coins in CRRO, OCRE, and PELLA.

Updating NUDS and Numishare

The NUDS XSD schema has namespaced METS for capturing image links for thumbnails and reference images for both the obverse and reverse of the coin. A mets:file[@USE='iiif'] has been added into the mets:fileGrp for both the obverse and reverse. The mets:FLocat URL points to the IIIF service. This is a simple XML model modification that needed to be addressed in Numishare's code in several contexts:

IIIF images rendered in Mantis

  • If there's a mets:file[@USE='iiif'] detected when rendering the HTML page for an object, the obverse and reverse IIIF services are rendered with Leaflet (above)
  • As above, in the NUDS->RDF serialization, the EDM IIIF extension includes an edm:WebResource, svcs:Service to capture IIIF service metadata
  • The Solr->Nomisma, Pelagios RDF for large data exports will now include IIIF service metadata since the service URI for each image is indexed into Solr

 

Manifests

I have authored an XSLT stylesheet that transforms the NUDS XML document for a physical object into a JSON manifest. This transformation process extracts metadata from the NUDS typological and physical descriptions and generates a sequence of two canvases: one for the obverse and the other for the reverse.

This XSLT compiles a variable of an XML metamodel by applying templates to NUDS and METS elements. This metamodel is then piped through templates in order to construct JSON. The metamodel includes XML elements such as _array, _object, __@id, __@type, which are then transformed into proper JSON on the output with Orbeon's XML Pipeline Language. The model is similar in concept to how XForms constructs an XML model from a JSON service according to the XForms 2.0 specification.

You can view an example of a manifest at http://app1.numismatics.org/search/manifest/1995.11.1648. Here it is rendered in Universal Viewer.

I plan to expand this functionality so that IIIF manifests can be derived from NUDS + SPARQL results for coin types so that it will be possible to see a listing of all available images for a coin type, which will lend itself to more efficient annotation of iconographic features, monograms, and other sorts of symbols. These monograms will link to URIs defined in type corpora. We will be creating the full array of Hellenistic monograms as part of the NEH-funded Hellenistic Royal Coinages project. Ultimately, I would like these monograms to be annotated on images, where available. This isn't a feature of the project that we outlined in our application, but will come as an added bonus.

Tuesday, August 22, 2017

More mapping features for Nomisma SPARQL responses

Edited 23 August 2017: changed getGeoJsonForQuery to query.json and getKmlForQuery to query.kml

The Nomisma.org SPARQL query HTML interface, for both SELECT and CONSTRUCT/DESCRIBE responses, has been extended generate a map when the query response includes latitude and longitude geographic coordinates (when using the geo:lat and geo:long RDF properties).

The introduction of this new feature necessitated the creation of a new API, query.json, which is essentially an XSLT transformation from either the SPARQL XML response schema or RDF into GeoJSON. The XSLT was extended from existing templates for the other GeoJSON responses for getting the geographic distribution of mints, hoards, or individual finds for a Nomisma concept ID or a coin type.

The query (get a list of hoards that contained tetradrachm coin types [based on PELLA])


PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX dcterms: <http://purl.org/dc/terms/>
PREFIX geo: <http://www.w3.org/2003/01/geo/wgs84_pos#>
PREFIX nm: <http://nomisma.org/id/>
PREFIX nmo: <http://nomisma.org/ontology#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>

SELECT DISTINCT ?hoard ?findspot ?lat ?long WHERE {
  ?type a nmo:TypeSeriesItem ;
          nmo:hasDenomination nm:tetradrachm .
  ?coin nmo:hasTypeSeriesItem ?type ;
        dcterms:isPartOf ?hoard .
  ?hoard a nmo:Hoard ;
           nmo:hasFindspot ?findspot .
  ?findspot geo:lat ?lat ;
            geo:long ?long
}

is therefore rendered as the image below:

Map response for SPARQL query, http://bit.ly/2v36y9t
The GeoJSON response is rendered in Leaflet with the MarkerCluster plugin. Similarly, by replacing SELECT DISTINCT with DESCRIBE, the map will also render when coordinates are available within the RDF output from the SPARQL endpoint. See here.

Furthermore, I introduced a query.kml API, which accepts the same SPARQL query parameter and outputs KML instead of GeoJSON.

The SPARQL results page now has links to download the result set in CSV for SELECT queries and RDF/XML, Turtle, and JSON-LD for CONSTRUCT/DESCRIBE, as well as links to the GeoJSON and KML responses when geographic distributions are available.

Tuesday, June 20, 2017

Experimenting with 3D integration in OCRE

The Wild West of 3D Capture in Cultural Heritage


The lowered technical barriers and costs of 3D capture (especially photogrammetry) within the museum and archaeology domains has seen an explosion of 3D data within the cultural heritage sector. The Smithsonian X 3D and British Museum (led by Nomisma scientific committee member, Dan Pett) endeavors are among the best recognized efforts in this area, but 3D cultural heritage models (from artifact scans to excavation trenches and entire sites) are being published to the web by many organizations through a wide variety of information systems. Many organizations have turned to Sketchfab as the primary mode of publication, but others are using home-grown systems. In truth, 3D publication is the wild west. There aren't even readily agreed-upon open standards for the models themselves, let alone metadata standards, publication frameworks or APIs for accessing models/metadata (in contrast to 2D images through IIIF standardization).

As such, integration of 3D data back into the scholarly research ecosystem has fallen very far behind 3D production capacity. We have seen that Sketchfab models can be embedded into web-based news articles or blogs (such as the Telegraph article above or Sarah Bond's recent post on Forbes), which have been an excellent medium for making these resources available to a general audience. However, we cannot overlook the fact that these are also valuable resources to a scholarly audience, and this audience isn't going to poke around various universities' institutional repositories or Sketchfab profiles for relevant 3D data. Numismatists studying Roman imperial coinage use Online Coins of the Roman Empire, and if there are 3D models of Roman coins, they should expect to access that material through OCRE and not Sketchfab directly. The same goes for Greek pottery experts and Kerameikos.org. Scholars more broadly interested in the ancient world may access 3D objects through Pelagios and more general audiences (both academic and public) may interact with these objects through Europeana or DPLA.

I have high hopes that the 3D GLAM community (including commercial entities such as Sketchfab) will move toward open standards for the dissemination of these data. Taking Greek pottery as an example, 3D models are much preferred over 2D photography for viewing inscriptions and iconography, and if 3D models can be annotated following the same standards we see in IIIF (Open Annotation RDF), scholars will be able to view all objects depicting Dionysus, regardless of the 2D/3D medium of capture.

Sketchfab models in OCRE, a Proof of Concept


The coin cabinet of Heinrich-Heine-Universität Düsseldorf, a Nomisma partner through the NUMiD network of German university coin cabinets, recently uploaded three models to Sketchfab: a Roman provincial coin showing the damnatio memoriae of Geta, an imperial coin of Severus Alexander (RIC IV 455), and an imperial coin of Constantine (RIC VII Constantinople 126). The latter two coins have already been integrated into OCRE, and so I set forth on the task of incorporating triples for the 3D models into the RDF for these two coins.


Fortunately, two librarians at the University of South Florida, Xiying Mi and Bonita Pollock, have put forth a useful proposal at ALA (see Linked Metadata for 3D-Models: From Dublin Core to Europeana Data Model) to capture some basic 3D model metadata and associate this information with the cultural heritage object.

Since we have already implemented the IIIF extension for the Europeana Data Model in Nomisma, it was fairly straightfoward to link to a 3D model in much the same manner by using the edm:isShownBy property to link to the Sketchfab URI, which is cast as an edm:WebResource class. This edm:WebResource carries some additional metadata about the model itself, including the capture process (photogrammetry as a dcterms:format linking to a Getty AAT URI, etc.).

A 3D model of a coin of Severus Alexander, shown in OCRE
These data model adaptations were followed by some updates to Numishare's underlying SPARQL query and UI scripts to render the 3D model, when available. There is a conditional within the Javascript to use an iframe to embed the Sketchfab model when the edm:WebResource is a Sketchfab URI. So far, there's only one condition for rendering. Ultimately, the scripts will read the mime-type from the RDF metadata and use an open source JS 3D library accordingly (such as Universal Viewer).

This of course is predicated on the cultural heritage community coming to an agreement on open standards for 3D models and APIs for accessing these models and associated metadata. In this endeavor, I see myself as a consumer of 3D--not for my own research purposes, but as a technical developer building middleware for scholars to access the models to achieve their needs. In my role as a consumer, I hope to be able to steer the content producers and architects of 3D information systems onto a path that results in the greatest potential for reuse and synthesis.

Thursday, June 8, 2017

Updates to symbol/monogram pages in OCRE

I have just pushed some changes to symbol and monogram pages in OCRE, which are more broadly applied to Numishare. Up to this point, we have published several dozen late Roman monograms from RIC 10 and a small handful of Siscia Officina marks from RIC 8. The data underlying these symbols are in RDF, conforming to the Nomisma ontology and data model. The web pages displayed little more than a list of metadata about the symbol, but no further context. Altogether, these pages weren't particularly useful as scholarly tools.

Map of Marcian monogram 1

Following updates to Nomisma, I have implemented two new features on symbol pages:

  1. A map showing the distribution of mints and findspots (a heatmap layer showing all findspots and individual layers for finds and hoards). The geoJSON APIs in Nomisma were extended to support SPARQL queries for geographic data by passing a 'symbol' request parameter. See http://nomisma.org/apis#getMints, for example.
  2. A list of coin types that bear these symbols, with available images, when available. The list of types is downloadable as CSV, and the user can click a button to view the underlying SPARQL query, which could be copied, modified, and submitted directly to Nomisma's endpoint (see below).

Coin types that show Marcian monogram 1

Below is the SPARQL query for getting a list of types associated with a monogram, with some basic metadata:

SELECT ?type ?label ?startDate ?endDate ?mint ?mintLabel ?den ?denLabel WHERE {
  {
    SELECT ?side WHERE {
     ?side nmo:hasMonogram <%URI%>
    }
  }
?type ?prop ?side
   MINUS {?type dcterms:isReplacedBy ?replaced}
   ?type a nmo:TypeSeriesItem ;
   skos:prefLabel ?label FILTER(langMatches(lang(?label), "en")) .
   OPTIONAL {?type nmo:hasStartDate ?startDate}
   OPTIONAL {?type nmo:hasEndDate ?endDate}
   OPTIONAL {?type nmo:hasMint ?mint . 
    ?mint skos:prefLabel ?mintLabel 
       FILTER(langMatches(lang(?mintLabel), "en"))}
   OPTIONAL {?type nmo:hasDenomination ?den . 
    ?den skos:prefLabel ?denLabel 
       FILTER(langMatches(lang(?denLabel), "en"))}
}

Since these features are now inherent to Numishare, they will be available for the enormous array of Greek monograms that will be published as part of the Hellenistic Royal Coinages project. I hope to have a prototype of a few monograms published in PELLA within the next few weeks.

As more and more Nomisma partners adopt IIIF, these monogram URIs will form a basis for image annotation, and eventually these symbol pages will use Open Annotation and IIIF APIs to display photographic examples of monograms, in addition to a print and web-ready idealized SVG renderings.

Friday, May 19, 2017

Nomisma measurement analysis interface ready for wider testing

I have been working on and off for the last month or two on a new quantitative analysis feature in Nomisma, which is available on pages for certain types of Concepts (that are associated with coin types that have been ingested into Nomisma) as well as on a new page, http://nomisma.org/research/metrical.

Much like the distribution analysis interface, the user can select multiple dataset groupings to compare for average weight or average diameter. Optionally, and like the existing features in OCRE, CRRO, and PELLA, the user can input a start date and end date and an interval of 5 or 10 years in order to visualize the change in average weights over time. The parameters established in the web form are used to query a web service, which interacts with Nomisma's SPARQL endpoint and serializes the response into JSON for visualization.

Average weight of denarius (red), aureus (yellow), and antoninianus (blue) from 100 BC to AD 300. See for yourself.

What separates this interface from the feature that is built into Numishare projects (like OCRE) is that the weights are drawn from all relevant coins, regardless of an explicit connection to a coin type defined by a URI published by OCRE or similar project. This means that coins from Antike Fundmuenzen Europa or other finds databases that do not have positively identifiable RIC numbers can be queried alongside those that do, as long as those relatively uncertain coins still have some certain attributes, such as authority or denomination. Moreover, these interfaces allow the querying across related, but separate datasets--e.g., to evaluate the change in average weight of denarii from 100 B.C. to A.D. 100, even though the denarius coin types are split between OCRE and CRRO starting about 27 B.C.

The raw data can be downloaded as CSV for further analysis, visualization, or publication, and the chart for the metrical analysis page can be reproduced easily by bookmarking the resulting URL.

Weight of Augustan denarii from Rome compared to Lugdunum


Known Limitations

The metrical analysis feature is still a working proof of concept that will be refined and enhanced over time.

First, we do encounter coins that are either cataloged with the wrong RIC number or the automated matching script erroneously interprets a reference into the wrong RIC number, so the weights of these coins may have an effect on the overall average for a query. I think, in most cases, the margin of error is quite small.

The charts are visualized with a d3.js plugin called d3plus. There's an error in the handling of BC dates (according to the ISO spec), and so (in interval queries), the dates are converted to an integer value. So -100 is 100 B.C. and 200 is A.D. 200. As a result, the d3plus line graph cannot be set as a timeline, and therefore date ranges that do not contain weight data are removed from the chart. It is important to be able to visualize gaps in weights, as these gaps may illustrate periods where coin types conforming to a query were not issued (for example, there is no weight data for aurei from 70-50 B.C.).

One last thing to note is that I have not been able to manually override the x-axis labels, so -100 actually means 100 B.C. to 96 B.C. when the interval is set to five years (not just 100 B.C.). The human readable date range is still available when hovering the mouse over a point in the chart and in the CSV download.

Next Items

Aside from minor alterations that should come when d3plus's B.C. date glitch is fixed, I plan to expand beyond average weight and diameter to showing weight+diameter as a cluster as well as standard deviation for measurements, which should be more illustrative of coins that do not conform with the norm, enabling them to be eliminated from further weight query, while also flagging them to collections as potentially erroneously attributed coins, counterfeits, partial specimens, or other such aberrations.

Friday, May 12, 2017

Extending Nomisma geoJSON for Temporal Data

The geoJSON output for queries for findspots and hoards associated with Nomisma.org concepts has been updated with the geoJSON-T extension, including closing or burial dates of hoards or individual finds, when known. Additionally, the properties following the geoJSON-T proposed model for gazetteer toponyms and URIs, e.g.:


{
      "type": "Feature",
      "label": "Meolo (Albaredo d'Adige) (Italy; ME2)",
      "id": "http://numismatics.org/chrr/id/ME2",
      "geometry": {
        "type": "Point",
        "coordinates": [
          11.27843,
          45.31859
        ]
      },
      "when": {
        "timespans": [
          {
            "start": "-0038",
            "end": "-0038"
          }
        ]
      },
      "properties": {
        "toponym": "Albaredo d'Adige (Italy)",
        "gazetteer_label": "Albaredo d'Adige (Italy)",
        "gazetteer_uri": "http://www.geonames.org/3183350/",
        "type": "hoard"
      }
    }


Furthermore, the getFindspots, getHoards, and heatmap APIs have been updated to accept a coinType request parameter instead of an id parameter in order to get relevant geographic data associated with coin type URIs, rather than associations with Nomisma-defined numismatic concepts. This is the first step in the eventual overhaul of the mapping features in Numishare coin type projects (like OCRE) to render geoJSON-T in Leaflet, finally retiring the TimeMap plugin that has not seen active development in at least four years.

Tuesday, May 2, 2017

KENOM project joins Nomisma/OCRE

The KENOM project, a consortium of 13 German institutions contributing into a central numismatic portal, has been integrated into Nomisma.org. More than 4,500 Roman Imperial coins from three institutions (The State Coin Collection of Munich, the Coin Cabinet of the University of Goettingen, and Thuringian Museum for Pre- and Early History) have been made available Online Coins of the Roman Empire. All of these coins have been photographed at a high resolution and are published following the IIIF specification, which are treated as zoomable images in OCRE, and will eventually be useful for more sophisticated iconographic annotation.

Augustus 171A


Below is a fuller description of KENOM:

KENOM (Kooperative Erschließung und Nutzung der Objektdaten von Münzsammlungen) is a long time project of different numismatic collections in Germany to bring their numismatic objects (coins, medals, paper money and also coin find-informations) together online. There are a common internal database of the project for the data input and a portal of presentation of qualified data and images. Goals of KENOM are the harmonisation of numismatic data of the partners, the integration of open linked norm data and the definition and use of a LIDO-based data exchange format. 2012-2015 the project was funded by the Deutsche Forschungsgemeinschaft, now KENOM is operated jointly. The strong technical partner of the project is the Gemeinsamer Bibliotheksverbund Göttingen. Today already 13 institutions present more than 33,000 numismatic objects together in the portal <http://www.kenom.de/>.

KENOM has developed lookup mechanisms that read OCRE and CRRO web services, making it easy for curators to link their collections directly to these Linked Open Data systems. The RDF data for OCRE were harvested from KENOM's OAI-PMH using a PHP script I put together yesterday afternoon. Project coordinator, Mario Schlapke, plans to write a more comprehensive post about the process of integrating KENOM with the wider ancient world linked data cloud.

Thursday, April 27, 2017

OCRE launches new interface to aid in identification of Roman coins

After years of discussion and labor by several people, we are pleased to announce a new interface for Online Coins of the Roman Empire that will aid in the identification of Roman imperial coins by non-specialists (archaeologists and collectors alike). We hope that this will be especially useful for badly worn coins discovered in archaeological excavation. Like the rest of OCRE and other ANS web projects, this interface is responsive to devices of various sizes, making it ideal for use on mobile phones and tablets in the field.



The interface, called "Identify a Coin", is a simplification of  OCRE's browse interface into the basic components that can help to narrow down a coin's visibly identifiable attributes. Selection to specific criteria leads the user into a restricted subset of matches for further comparison (aided by the great number of images associated with coin types provided by Nomisma.org partner institutions). For example, a user of this interface can select the type of metal and insert any recognizable characters on either the obverse or reverse legend, with wildcards ('*' characters) designating gaps in legibility. Importantly, the user can select from a nearly complete list of imperial portraits as potential matches. The portraits are listed chronologically, first by dynasty, and then by personage within the dynasty (including empresses and children). In many cases, portrait images are available in gold, silver, and bronze, as well as worn examples that one may encounter with stray finds or excavation. The selection of a material will automatically change the metal of the portraits, when a relevant image is available. More than one material may be chosen, which is useful for later Roman coinage, when severe wear makes it difficult to distinguish between what RIC has designated as "silver," "bronze," or "billon." By clicking the left and right arrows below the image, it is possible to scroll through available portraits, which may show several phases of portraiture, such as Nero, who grew from a teenager into adulthood over the course of his reign.

This interface is one of the most complete depictions of numismatic imperial portraiture, and we hope that it will also prove itself a useful art historical tool to trace the development of Roman portraiture from the Augustan period through the Soldier Emperors to the Tetrarchy until the end of the Roman Empire.

Many thanks to ANS curatorial assistant Disnarda Pinilla for identifying all of the portraits used in this interface. Although primarily drawn from the ANS collection, others are from Berlin, Vienna, or the Fralin Museum at the University of Virginia.

Monday, March 27, 2017

Bibliothèque nationale de France join Nomisma

The Bibliothèque nationale de France (BnF) has joined Nomisma, providing data for more than 2,000 coins of Alexander the Great, Philip III Arrhidaeus, and Lysimachus to PELLA, in time for the Oxford - Paris Alexander Project next week. Since Gallica implements IIIF, I have ingested IIIF image API metadata into Nomisma to make zooming possible. An example can be seen here.



There are now about 20,000 Alexanders in PELLA. With entry of the BnF into the consortium, now five of the most significant collections of ancient coinage contribute Linked Open Data to Nomisma and various related aggregation projects.

Florence Codine provided a concordance spreadsheet of Gallica and PELLA URIs, which I processed with PHP into RDF, extracting additional metadata from OAI-PMH. The script is on Github.

Friday, March 24, 2017

Münzkabinett Vienna joins Nomisma consortium

The Münzkabinett of Vienna is the newest member of the Nomisma consortium, providing data for about 1,500 ancient coins to OCRE, CRRO, and PELLA. Nearly 1,300 of these are Roman Imperial coins, 150 are Roman Republican, and about 100 Alexanders. Vienna is in the early stages of digitization, but it is one of the most significant collections of coins in the world.

The Münzkabinett of the Kunsthistorisches Museum Wien (Vienna in Austria) owns over half a million objects which make it one of the largest collections of its kind, and it can be traced back until the 16th century. It holds coins, medals and banknotes, but also coin dies, bonds and primitive money. Not only does the collection house unique rarities and priceless treasures, its abundance and completeness make it an essential tool for fundamental research in Numismatics and History.

The timing for Vienna's introduction into the numismatic linked open data cloud could not be more perfect. The Oxford-Paris Alexander project is convening in Oxford April 3-4, and so Vienna's entry into PELLA is a demonstration of the growing network of Greek coinage.

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.