I'm a freelance Digital Heritage consultant and researcher. Until returning to academia, I was the Geomatics Manager at Wessex Archaeology, responsible for survey and GIS. My skills are related to archaeological computing (GIS, databases, metric survey, laser scanning, spatial analysis, web mapping, cartography, database design, standards, semantic web, ontologies, CIDOC-CRM). My main research focus is currently geosemantic technologies in archaeology. I also have research interests in movement and perception in prehistoric landscapes. There's more about me on about.me

Archaeological Geosemantics, the final chapter

Panoramic View of the Stonehenge Landscape from Fargo Plantation

Panoramic View of the Stonehenge Landscape from Fargo Plantation

GSTAR IV: Return of the GeoJSON

Following on from my Days of Archaeology in 2013, 2014 and 2015 (and for the last time), the bulk of my Day of Archaeology this year focussed on my doctoral research, writing up my thesis on Geosemantic Technologies for Archaeological Research (GSTAR). It’s been a busy three years but the project is nearing completion and will hopefully inform heritage management and research strategy over the coming years.

The aim of the project was to show how geosemantic technologies can be used to provide a framework for working with heritage data in a range of research contexts. To this end, I have built a demonstrator application which is based around a map (obvs!) for the Stonehenge landscape and which draws data from Historic Environment Records, museums and project archives, allowing users to ask questions across these diverse resources taking advantage of the semantic goodness of Linked Geospatial Data, thesauri and ontologies. Geosemantic ‘glue’ was used to integrate horizontally between resources (such as monuments and artefacts found within or nearby) and vertically (ie between excavation records and monument/event HER records and museum collection records).

The ontologies used were the CIDOC CRM, CRM-EH and GeoSPARQL which allow the concepts used by the various sources to be aligned whilst the terminology provided by the thesauri (published using SKOS) allow for the various terms used to document these concepts to be related. In other words, the semantic tools allow for the different sources to be made interoperable and queryable with the results displayed and interacted with on a map.

Moving forward, the approach taken and successfully demonstrated could be scaled up to act as the basis for the next generation of heritage information portals; think of the Heritage Gateway but with some additional bells and whistles:

  • the ability to undertake proper geospatial queries and analysis, even where there is no GIS data
  • spatial queries mediated using geospatial semantics, to get away from purely Cartesian views of space dependent on geometry and the problems that entails for historic information
  • complex querying across all of the participating providers, with differences in terminology ironed out

The demonstrator application is built using a range of standard web and geospatial technologies. Currently, the accessioning process for data is largely manual, built using the STELLAR Toolkit to process outputs from MODES and HBSMR, two major software packages used in museums and HERs respectively. A next step would be to automate this, which would be fairly straightforward from a technological if not a political perspective. If an automated pipeline could be implemented across all the HBSMR and MODES using institutions and organisations, this would cover an enormous amount of heritage information and, combined with a map based portal and live feeds to desktop GIS, would greatly improve the way in which we undertake all kinds of research activities, both in academic and commercial contexts.

Information from site archives was a little tricksier, as one might expect; such data does not typically get archived in a readily useable fashion unlike information found within the structured systems used for managing Historic Environment Record data or museums collections. However, with ongoing work relating to the digital capture and sharing of fieldwork information through OASIS, HERALD and the broader Heritage Information Access Strategy (HIAS), we are undoubtedly moving towards a time when this becomes not just possible but the norm. When this happens (and note I say when not if!), we can start to extend Linked Data principles more fully to our information resources, so monument records can be directly built up from linked fieldwork records, museum collection artefact records can be layered on top of linked excavation finds records and, on top of all this, our Research Agendas and Frameworks can be truly data driven, dynamic resources drawing directly on this web of Linked Data, informing and informed by ongoing research and our shared knowledge of the past, across all of our information resources.

The use of such geosemantic ‘glue’ allows for a much more intelligent approach to finding and working with geospatial information from heterogenous sources split across numerous providers. Take the following query for example:

Show me all the Bronze Age mounds where dolerite has been found during excavations and carved chalk balls were discovered nearby.

Using the HeritageData Periods thesaurus, it is possible to mediate different uses of language across sources to describe time-spans relating to the Bronze Age, using broader, narrower and/or related terms. We can use the FISH Event Types Thesaurus to find event records relating to interventions (including excavations) and draw on the project archives for these to check for finds of dolerite, potentially using geological ontologies such as GEON to mediate identifications of rock types. Using the FISH Object Types Thesaurus, it is possible to do the same for chalk balls or any other artefact type. Geospatial information may well not exist for these objects as recorded in museums collections, most likely not in the form of British National Grid coordinates at least, particularly where they were discovered in antiquity. But we do often have some basic spatial information such as an associated location (eg Stonehenge), parish (eg Amesbury) or named place (eg Stonehenge Road); in such cases we can use the Ordnance Survey Linked Data plus some of the spatial relationships defined by the Simple Features specification (used by the GeoSPARQL ontology) to perform a spatial query using these index terms via a bit of geosemantic magic. Moving forward, we can align our research questions with such resources and queries so, for example, if the dating of carved chalk balls (typically thought of as of Neolithic origin) were to change, we can use the same approach to identify contexts where such changes would have a knock on effect or where our broader understanding of deposits, sites and complexes may also need to be updated or where new research questions arise. So this may be the end of the GSTAR project, but it’s only just the beginning for the use of such approaches within the heritage sector.

Many thanks again to everyone who has helped, contributed and otherwise supported this research project along the way, particularly:

  • Doug Tudhope, Alex Lohfink, Mark Ware & Ceri Binding (University of South Wales)
  • Chris Brayne (Wessex Archaeology)
  • David Dawson (Wiltshire Museum)
  • Adrian Green (Salisbury Museum)
  • Keith May (Historic England)
  • Melanie PomeroyKellinger (Wiltshire Council)

A Digital Day of Archaeology

Wooston Castle Local Relief Model draped over a 3D Digital Terrain Model, all based on LiDAR data and available on Sketchfab

Wooston Castle Local Relief Model draped over a 3D Digital Terrain Model, all based on LiDAR data and available on Sketchfab

As is usual for me, my day comprises working on digital heritage projects, as in my previous Days of Archaeology (2011a, 2011b, 2012, 2013 and 2014). So no archaeological features were harmed in the making of this post!

Although on one current project, my GSTAR doctoral research, I am indeed working with archaeological excavation data from the archives of Wessex Archaeology combined with museums collections data from Wiltshire Museum and also heritage inventory data from the Wiltshire Historic Environment Record. This project is nearing completion (thesis due for submission April-ish next year!) and having already shown that geospatial information can be published and used in Semantic Web / Linked Data contexts through the integration of ontologies, I’m currently building demonstrators to show how data can then be used to undertake archaeological research through framing fairly complex archaeological research questions as spatial queries asked across the range of resources I’ve included.

Today however, I’m working mainly on Archaeogeomancy commercial projects as I do one day a week. And thanks to the wonders of digital technologies, I’m working out of Bristol for a change; my first Day of Archaeology away from Salisbury. It’s been a busy week this week, clocking up quite a few miles, as Monday and Tuesday were spent at the Pelagios Linked Pasts event held at Kings College London where a diverse group from across the world spent a very productive couple of days talking about Linked Data with particular emphasis on people, places, space and time.

This morning’s tasks focussed on an automation project involving planning applications. I’m building a system which consumes planning data collated by Glenigan, classifies it according to type of project (as defined by the client) and then pushes out regional and property specific maps and summaries on a weekly/monthly basis for a list of properties which may be affected by these planning applications. This allows specialists in each region to assess each planning application and make recommendations regarding any responses needed. So whilst not the shiniest and most academically interesting of projects, it is the kind of GIS based systems development and automation that can really make a difference by freeing up staff time from the mundane production of such maps and reports.

This afternoon’s tasks will focus on another system I’m developing, this time to assist with the analysis and interpretation of LiDAR data. I’m building a toolkit which incorporates a select range of visualisation techniques requested by the client including Local Relief Maps, Principal Components Analysis and the usual hillshades, slope, etc. The toolkit is to be deployed to users who are not necessarily experts in the analysis and interpretation of LiDAR data or GIS so needs to be simple to use with many variables preset and also needs to be integrated within their corporate GIS solution rather than be a standalone application. The first batch of tools mentioned above are all complete and working nicely; this afternoon’s mission is to wrap up the Openness and Sky View Factor visualisations.

Indeed, it’s been great working with LiDAR data again lately. When thinking of a suitable image for this year’s Day of Archaeology post, the one shown above immediately leapt to mind. It shows a screenshot of the output of the Local Relief Model (LRM) tool I built draped over the Digital Terrain Model (DTM) for a rather lovely hillfort as viewed on Sketchfab. I mention this because disseminating informative views of LiDAR data has long been problematic, but platforms such as Sketchfab allow us to composite 3D and 2D products and then share them in an interactive way with anyone who has a web browser and an internet connection without the need for any specialist software at all. Nice.

A day in the life of a Postgraduate Research Student

Semantic graph of archaeological data

Semantic graph of archaeological data

Another year, another Day of Archaeology! Having moved on from the world of commercial archaeology, the source for my posts in 2011 (here and here) and 2012 (here), I’m now into the second year of my computer science PhD, investigating Geosemantic Resources for Archaeological Research (GSTAR) based in the Hypermedia Research Unit and Geographic Information Systems Research Unit at the University of South Wales. Today is a busy day (as usual!) wrapping up a pilot study for my PhD, writing up my Transfer Report (to move from MPhil to PhD proper) then later on, doing a bit of paid consultancy work to keep the wolf from the door. Whilst I am lucky to have a fully funded place, taking on a PhD later in life, as I have have, when you have a mortgage and two kids to support is challenging to say the least. But thoroughly rewarding nonetheless; I’m hopeful that my research can really make an impact on how we use digital heritage data within the historic environment sector and further afield but I guess we’ll just have to wait and see…

The fusion of semantic technologies and GIScience

My literature review identified two strands of discourse within two distinct domains, each looking at how to deal with geospatial data within semantically enabled frameworks. To give you an idea of this, see the figure below which shows a Positive Stratigraphic Unit (ie some kind of layer, deposit or structure) modelled using the CRM-EH ontology and including spatial relationships. There’s some more detailed description of this modelling here including various other classes used in archaeological excavations.

Modelling Positive Stratigraphic Units

Modelling Positive Stratigraphic Units

Firstly, within the web science arena, researchers are trying to integrate geospatial data directly within semantic resources. Geospatial data is structured using ontologies and held within triplestores alongside all other data, with geometries stored as Well Known Text (WKT) or Geographic Markup Language (GML). Both these formats are means of representing geometries using plain old text which can be embedded within semantic structures. This geosemantic data can then be accessed via ‘endpoints’ or APIs (ie web services) using an extension to the SPARQL language called GeoSPARQL which handles spatial objects and operators in addition to semantics. Such an approach also facilitates integration of other Linked Geospatial Data resources, such as those provided by the Ordnance Survey.

Secondly, within the GIScience arena, researchers are looking at leveraging the existing capabilities of Geographic Information Systems (GIS) and Spatial Data Infrastructures (SDI) alongside semantic technologies such as triple-stores, SPARQL endpoints and the like. This way, the established highly tuned, highly efficient spatial services such as Web Feature Services (WFS) can do their thing, optimised for handling large amounts of complex geospatial data, whilst the newer semantic systems can contribute, providing the necessary semantic support.

My pilot study has been looking at these approaches with a view to their application within archaeological resources and has resulted in a system I have used to investigate the pros and cons of different methods. It’s a Java application, built using the Eclipse IDE and using Maven to handle the various external libraries I need to work with spatial and semantic data. These include the Jena framework (for semantic support), GeoTools (the Swiss army knife of geospatial Java programming), GeoServer (a lovely GIS server), some supporting libraries for handling CSV data. There are also some other bits and bobs such as the Jetty and WebLogic webservers to serve applications and provide access via http. The data store I’m using for both geospatial and semantic data is Oracle 12c, the very latest incarnation of this powerful application, which has good support for geospatial data, RDF, SPARQL and GeoSPARQL via it’s updated Spatial and Graph component.

The data for this study comes from the Archaeology Data Service (ADS) and is one of the Channel Tunnel Rail Link (CTRL) projects which has useable spatial data available for download and was also one of the resources used in the Stellar project (published as Linked Data at the ADS),so the data is already available in RDF format compliant with the CRM-EH extension to the CIDOC CRM ontology. The availability of the semantic data allowed me to steam on ahead without having to spend time preparing semantic data from a typical relational structure, although this is fairly easy to do with the Stellar Toolkit (as I did on the Colonisation of Britain project).

The write up from this is forming a big chunk of my Transfer Report, currently in draft to be wrapped up and submitted imminently. A fuller write report will form a chapter or two in my final thesis. There’s a bit more technical info over on my GSTAR blog.

A bit of work on the side…

A condition of my funding is a limitation on the amount of paid work I can do on the side. To be fair, this is entirely understandable; a PhD requires concentrated attention and and distractions can be highly counter-productive. But, I do need to feed my family and pay the bills so I do the full amount (6hrs/week) of consultancy for various clients through my own business, Archaeogeomancy, and through the digital heritage specialists Archaeovision. Having such a restricted programme means I have to be picky about which projects I take on but the flipside of this is that I only take on projects I can reasonably undertake and which interest me in some way. A bit of a change from working for a commercial company and having lots of management tasks to contend with and having to support whichever projects were sent my way. Although I do now have to do all my own accountancy and admin… 🙁

The Old Fire Station, Church Lane, Lincoln by Lincolnian

The Old Fire Station, Church Lane, Lincoln by Lincolnian

I’m currently working on some systems development for a client assessing police and fire stations across England, a lovely piece of work which is generating a gazetteer of sites including all manner of interesting data. The system I’m developing is a fairly typical relational database backend with an associated GIS for a spatial perspective and producing cartographic outputs for reporting. Whereas my PhD largely uses Open Source software for everything, as that is where the development focus is with academic research software, this project is back to my old toolkit of Microsoft Access, ArcGIS and some bespoke tools built around this. The bulk of this system is now complete, a draft version has already been handed over, and today I’ll be loading a revised dataset and adding additional tools to deal with specific tasks the users need to accomplish.

It’s always good to branch out too and another ongoing project I need to do some work on over the weekend is a non-archaeological spatial information system. It’s a system for assessing potential ecological impacts and strikingly similar to the kinds of approaches we archaeologists use to undertake Environmental Impact Assessments and to complete Heritage Statements and the like. So whilst there isn’t a heritage angle, my skills and experience can be brought to bear on GIS work in another environmental discipline; something current students ought to bear in mind when they come to look for jobs!

A day of spatial semantics, digital excavation data and other things

Archaeologists tools: The laptop is now very much part of this armoury.

Archaeologists tools: The laptop is now very much part of this armoury.

Following on from my previous posts in 2011 (here and here) and 2012 (here), this year it’s a bit different. I’ve left the world of commercial archaeology to return to academia, starting a PhD in geosemantic technologies for archaeological research (GSTAR) based in the Hypermedia Research Unit at the University of South Wales with input from the Geographical Information Systems Research Unit. I also now undertake freelance digital heritage consultancy work for various clients in the public, commercial and charitable sectors through my business Archaeogeomancy.

Last Friday, the Day of Archaeology, was a fairly typical day involving some research and a bit of commercial work. I have a number of ongoing projects, a number of which required some input last Friday. And spending a bit of time with my latest daughter, three week old Florence (who has yet to show any interest in archaeology, unlike her big sister Amelia who loves ruins). One thing I rarely get to do these days is dig, my time being almost entirely filled with research, writing and other desk/computer based activities. But I still very much consider myself an archaeologist, it’s just that my tools are different. The photos I’ve used all come from my Flickr stream and are of archaeological sites, hopefully just a bit more interesting than photos of my computers…

Research

Finds bags

Finds bags containing instances of the class Physical Object, discovered through a Finding Event

I am currently wrapping up the literature review section of my PhD and heard last Thursday that my three month review has been accepted so full steam ahead. I’ve been looking at the range of Semantic Web and Linked Data technologies out there with particular reference to archaeological and heritage applications. Within this subject area, the GSTAR project is focussing on spatial data and geosemantic techniques and builds on the preceding STAR and STELLAR projects, collaborations between the University of South Wales, English Heritage and the Archaeology Data Service.

I’ve also been working on some refinements of an ontological model, the CRM-EH, further clarifying aspects relating to the formation of archaeological features, deposits and the deposition of artefacts. Preliminary results are posted here on my blog, which I use to talk about my work in digital heritage and interesting things I come across.

Consultancy

In addition to my research, I am currently working on a number of exciting projects for clients. I have just deployed an archaeological information system to facilitate the interpretation of marine geophysics data based around Microsoft Access and Esri ArcGIS; this is currently in beta testing which gives me an opportunity to complete other projects including some tools, again built using Esri ArcGIS, to support data collation, synthesis and reporting/cartography for Desk Based Assessments (DBAs) including Environmental Impact Assessments (EIAs).

Digging

Digging, the activity which reveals archaeological features, deposits and the stratigraphic relationships between them.

Another interesting project I was working on last Friday involves the creation of a Linked Data resource relating to the recent excavations at Silbury Hill, near Avebury, Wiltshire. This site is very dear to me, having featured in my undergraduate and masters dissertations which investigated the formation of landscapes in prehistory and the spatial patterning of archaeological remains by means of movement and perception of human scale actors. This Linked Data resource relates to the later Roman activity at the site and currently comprises c.40K assertions about contexts, stratigraphy, finds and samples all held in a triple store which will be published in due course to further add to the growing number of Linked Data resources online.

A day of archaeological geomatics

Unmanned Aerial Vehicle in flight.

Unmanned Aerial Vehicle in flight.
Image © Callen Lenz

Well, firstly, I can’t believe it’s been a year since last time! Doesn’t time fly? What’s happened since then I hear you cry? I’m still the Geomatics Manager for Wessex Archaeology, responsible for GIS and Survey. The big news is my desk is now paper free and I’m trying to keep to a paperless work regime, essential seeing as most of my workspace is taken up with computer equipment, leaving no room for unnecessary clutter. In the photo you can see not only my laptop but the recently rebuilt GISBEAST machine with it’s quad cores, 64-bit OS and 12Gb RAM, tooled up with all the software I need to do what I do. (more…)

The best laid plans…

Well, following on from my previous post, my Day of Archaeology turned out to be rather different than planned. This is certainly not an unusual occurrence; working in archaeological computing in a commercial environment, all manner of things can crop up and cause the most carefully planned day to head off in another direction altogether.

Firstly, my LiDAR data didn’t arrive so that bit went out of the window. And a whole bunch of meetings were convened, so a big chunk of the day was spent planning upcoming projects and working on management topics. I did end up doing a bit of survey support, preparing some survey instruments for the following weeks work and helping one of the Wessex Archaeology fieldwork teams with a GNSS problem they were having. I also devoted some time to preparing a submission for a metric survey project which will include some Terrestrial Laser Scanning (TLS) and some Polynomial Texture Mapping (PTM), a form of Reflectance Transformance Imaging (RTI). I also looked at the final specifications for another TLS project due to start fieldwork imminently. TLS is rapidly becoming the most efficient and cost effective means of capturing 3D metric data for recording and analysis of archaeological sites, structures and landscapes and one aspect of my job is managing such projects. I also currently do much of the processing, analysis and visualisation work on the resulting point clouds (and watch out for some videos of previous projects coming soon to the Wessex Archaeology Computing Blog).

A colour orthographic image of a castle, produced directly from Terrestrial Laser Scan data

A colour orthographic image of a castle, produced directly from Terrestrial Laser Scan data

But by far the best part of the day was spent doing one of my favourite activities: Systems design and development. I am currently building an integrated GIS & database application for managing and interpreting marine geophysics data. As with any good software application, it needs to effectively support the processes applied by the users, in this case the marine geophysics team. The data structure needs to be based around a solid and robust model of the information recorded; it needs to record not only the raw and interpreted data but the necessary Quality Assurance and metadata needed for analysis and reporting. I do enjoy this kind of work as it is creative and logical at the same time and to get it right, one needs to understand the detail and nuances of the processes being developed for, a good opportunity to find out more about different areas of archaeology (I have previously developed context recording systems for archaeological fieldwork, diver recording systems for marine archaeology and a variety of recording and analysis systems to support projects such as Environmental Impact Assessments and Conservation Management Plans).

My evening was indeed spent as planned finishing off a paper for publication. Whilst my main interest is in archaeological spatial technologies, I also have research interests in the application and development of data standards, thesauri and ontologies. My paper was based on how these various strands are coming together to support and arguably change the way in which archaeological theory is formulated, giving archaeologists the tools to discover information more easily and then develop more data driven theoretical assertions.

So a little bit different to what I had planned but I do hope still of interest to some.

Archaeology + spatial geekery = archaeogeomancy

Survey at Stonehenge

Survey at Stonehenge

A few words of intro before the full and glorious meat of archaeological computery geekery that will ensue through the day. My name is Paul Cripps and I am the Geomatics Manager at Wessex Archaeology. The title of this post comes from my blog, Archaeogeomancy, where I usually talk about things I’m doing, researching or otherwise interested in, focussing on archaeological geomatics. Bit of a play on words there (as described here) based around the term geomatics. Many people ask me what is geomatics and I generally quote verbatim the rather good wikipedia entry:

Geomatics (also known as geospatial technology or geomatic engineering) is the discipline of gathering, storing, processing, and delivering geographic information, or spatially referenced information.

(more…)