Category Archives: SEAHA student paper

SEAHA students present at the ICON conference in Belfast

The Institute of Conservation’s (ICON) triennial conference took place in Belfast from the 12th to 14th of June. Hundreds of delegates from numerous national and international universities, research institutes, conservation practices and heritage organisations were present for three days of conference sessions and special events. SEAHA was well represented, with papers by Cristina, Martin and Gavin. The Mobile Heritage Lab was also parked outside the conference venue, hosting demonstrations on participatory research, machine learning and the Oddy Test.

During the presentation titled “Simulation modelling: A learning laboratory for preservation management support”, Cristina introduced the use of simulation to explore the effect of preservation options during the lifetime of archival and library collections, regarding preservation, access and costs. The proposed approached, a hybrid model combining system dynamics and agent based modelling, captures the heterogeneity of the collections and allows the use of disparate data sources. The uncertainty level of the model when reliable data is not available was also discussed.

Martin presented research on Reigate Stone decay at the Tower of London. He used non-destructive testing and environmental monitoring to link observable decay patterns to distinct micro-climates. The findings will help determine the requirements of preventive conservation strategies.

The paper that Gavin presented at ICON was on his earlier work designing an algorithm for rock carving outlining and identification beneath lichen using Stonehenge as a case study. He also presented his current work using a supervised machine learning method to automatically identify the presence of carvings on bare rock surfaces.

The conference programme was huge. The first conference day saw guided tours of important heritage sites in and around Belfast, including the city’s street art and murals and Hillsborough Castle. The next two days saw 7 parallel sessions on topics ranging from textiles to ethnography, leadership to new conservators, and heritage science to collections care. These were book-ended by plenary sessions that included keynote presentations by Eleanor Schofield on the Mary Rose and Meredith Wiggins on #climateheritage.

With so much going on it was difficult to get an overall perspective, but it was clear that the conference was bursting with ideas and energy. This was a meeting place for long-standing colleagues and newly formed collaborations. Whilst the weather didn’t always play along, Belfast provided a vibrant backdrop with all the necessary infrastructure for keeping conversations going well past the last round of questions.

The conference ended on a unique high with the mysterious sounding ‘steam jazz night’. Delegates were taken for a ride up and down the Antrim coast on a genuine steam train. The train had been lovingly restored right down to the timber panelled wagons and was resplendent with personnel and passengers in period costume and a full jazz band. Every 20 minutes or so the train would stop at a small station and the ensemble would spill out, cakewalking, lindy hopping and boogying across the platform as the jazz band hit up a jaunty tune. It was a great way to round off this conference and create some stories to be retold at the next one in 3 years time.


Martin Michette is a DPhil student based at the University of Oxford in the School of Geography and the Environment. Martin is partnered with Historic Royal Palaces and Carden & Godfrey Architects. His project aims to develop preventative conservation strategies for Reigate stone at the Tower of London. 

“Wrapping stone blocks in plastic sounds odd? Give it a try…”

– Heather Viles, co-author and SEAHA CDT Co-Director

SEAHA CDT Alumnus Scott Allan Orr and supervisors from the University of Oxford, Historic Environment Scotland, and the Consarc Design Group has published a paper that presents a more accurate method for understanding how the output of non-destructive moisture measurement methods relate to the actual amount of water present.

Non-destructive techniques can be an informative part of understanding how a building is functioning in relation to its environment. They are based on measuring a physical property or phenomena, such as the interaction with electromagnetic energy, as a proxy for the amount of moisture present. However, since these measurements are influenced by several factors, such as the material, they are converted into arbitrary units to indicate relative levels of moisture.

The process of gravimetric calibration involves taking measurements with a non-destructive technique of a sample of the material of interest at several moisture contents (measured by mass) to characterise the relationship between them. Ideally, this is a directly proportional relationship (a straight line, more or less)—however, this is rarely the case. The samples need to be an appropriate size. For devices that measure within a large area, this means that the samples need to be suitably large as well.

Previous work has developed calibrations with samples that are first saturated, and then monitored while they dry out. While this is suitable for smaller samples (i.e. for calibrating devices with a small measurement area), this paper demonstrated that for devices with large measurement areas the samples of necessary size take much longer to dry out, resulting in a significant unequal distribution of moisture within the sample. This wreaks havoc on the calibration results.

To address this challenge, this paper validates that the calibrations are more accurate when using an approach described as ‘isolated diffusion’. This involves using several samples of the same material, and sealing them with impermeable plastic so that the moisture has time to evenly distribute throughout the sample. This results in more accurate and more consistent understanding of the device output from non-destructive techniques for moisture measurement.

The technique does not require any specialist equipment except for a suitable balance, meaning that it can be used by practitioners and researchers alike. It is particularly suitable for electromagnetic devices such as microwave-based tools and radar, since these do not direct contact with a surface to provide a consistent and accurate measurement.

Read the Open Access article on the website of the Journal of Applied Geophysics.

 


Scott Allan Orr is a researcher within the Oxford Rock Breakdown Laboratory (OxRBL) and a Stipendiary Lecturer in Physical Geography at St Catherine’s College, Oxford. He is currently working with Historic England to produce guidance on moisture measurement and monitoring in historic buildings and building materials. He is a Member of the Royal Society of Chemistry and part of the Management Group of the Council on Training in Architectural Conservation (COTAC).

Scott holds a BASc in chemical and environmental engineering from the University of Toronto, where he contributed to projects incorporating environmental monitoring and urban spatial distribution of atmospheric aerosols. From 2014 to 2018 he was a member of the EPSRC Centre for Doctoral Training in Science and Engineering in Arts, Heritage, and Archaeology, undertaking an MRes and DPhil at University College London and the University of Oxford, respectively. This project was undertaken in collaboration with Historic Environment Scotland and the Consarc Design Group, a leading heritage conservation architecture firm based in Belfast but working throughout the UK. In 2016, Scott was a visiting researcher at the German Federal Institute for Materials Research and Testing in Berlin.

Keats Webb PhD research into heritage science topics with the centre for doctoral training SEAHA recently presented at imaging conference. Webb presented research on modifying a digital camera for 2D and 3D spectral imaging of cultural heritage documentation.

Keats Webb presents paper on using digital camera for heritage imaging

SEAHA student Keats Webb recently presented the paper ‘Spectral and 3D Cultural Heritage Documentation using a Modified Camera‘  at the International Society for Photogrammetry and Remote Sensing.

Webb’s paper presented the characterisation of a modified digital camera to investigate the impact of the modification on the spectroradiometric and geometric image quality with the intention of the device being used for cultural heritage documentation. This modification of a consumer digital camera would provide a less expensive, high resolution option for 2D & 3D spectral imaging.

Read ‘Spectral and 3D Cultural Heritage Documentation using a Modified Camera’ here.

Keats Webb is a SEAHA student based at the University of Brighton. Supported by the Smithsonian Museum Conservation Institute and Analytik Ltd, her project explores integrated approach to spectral and 3D imaging for improved monitoring of cultural heritage objects. 

Image: Pixabay.