SACM - Ireland
Permanent URI for this collectionhttps://drepo.sdl.edu.sa/handle/20.500.14154/9656
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Item Restricted A Lifecycle-Based Metadata Model for Improving Documentation, Reuse, and Generation of Declarative Mappings(Saudi Digital Library, 2026) Alzahrani, Sarah; O'Sullivan, DeclanDeclarative mappings play an essential role in knowledge graph construction and data integration, enabling data transformation, alignment and interlinking of heterogeneous data sources. Despite their importance, mappings as semantic artefacts are rarely accompanied by the contextual documentation needed to understand why and how they were created. As a result, finding, assessing, maintaining and reusing these mappings becomes difficult. Existing standards such as PROV-O, DCAT, and SSSOM address aspects of provenance and alignment documentation but do not capture the full lifecycle of declarative mappings across different mapping types. This gap limits the ability to reuse, store and discover mappings in repositories, and also limits the ability of automated tools, including Large Language Models (LLMs), to generate reliable mappings without sufficient context. This thesis addresses this gap through the design and evaluation of the Lifecycle-Based Metadata Model for Declarative Mappings (LMMD). LMMD organises metadata according to five phases of the mapping lifecycle: analysis, design, development, testing, and maintenance. The model is designed to apply across mapping types including uplift mappings, ontology alignments, and entity interlinking, and can be used and extended accordingly. LMMD is then formalised as the Mapping Metadata Vocabulary (MMV), an OWL ontology aligned with established vocabularies including PROV-O, DCTERMS, and MQV. MMV is operationalised through MetaSEMAP, a web-based annotation tool that enables practitioners to document and export metadata for mapping artefacts. The thesis presents five evaluation studies. The first study is a community survey that validated the relevance of proposed metadata fields with semantic web community members. The second study assessed usability of MetaSEMAP through task-based testing. The third study examined the conceptual clarity, lifecycle coverage, and modelling quality of MMV through expert review and automated validation. The fourth study investigated whether lifecycle-based metadata supports more informed mapping reuse decisions. Finally, a use case explored whether metadata guided prompting improves semantic correctness and completeness of LLM generated mappings. The results demonstrate that LMMD provides a relevant, usable, and valuable foundation for mapping documentation and reuse decisions. The findings indicate that a lifecycle-based metadata model addresses a genuine need in the knowledge graph and data integration community, with broader implications for FAIR data practices, mapping governance, and AI-assisted mapping.10 0Item Restricted Detecting and Quantifying TiO2 Size Distribution and Oversize in Ink Nanosuspensions by Resonance Light Scattering (RLS)(2023-04-01) Alzahrani, Sarah; Ryder, AlanConcentrated nanomaterials suspensions are currently being commercialized for numerous applications. To measure the properties of such suspensions, conventional characterization techniques may require extensive experimental procedures, including sample pre-treatment and/or dilution. Novel techniques need to be developed to measure the properties of concentrated suspensions sensitively and reproducibly without sample dilution. In this work, resonance light scattering (RLS) data was assessed as a promising tool to monitor the concentration and size of nanoparticles in concentrated commercial ink suspensions. This project aimed to develop a reproducible RLS method for concentrated nano-suspensions quantifying analysis using triangular or square cuvettes. Second, it used RLS to determine a simple, robust, reproducible method for assessing the size and concentration changes of TiO2 and white inks. Third, to identify a method to detect and measure oversized TiO2 nanoparticles in a matrix of smaller particles in the white ink nano-suspension. For single ink investigations, UVVIS absorption data were recorded to assess the optimum dilution factor (DF) of the TiO2 white inks. The results showed that the absorption spectra started to become smoother at a DF of 11,000, which was found to be the minimum DF required to obtain a reasonably smooth absorption spectra curve. As for DLS measurements, the value of the Z-average was exponentially correlated to the value of sample DF, with an R 2 value of 0.99. This correlation shows that DLS can be used as a reference calibration technique to track the concentrations of single ink suspensions. RLS spectra were recorded for diluted ink suspensions using two types of cuvettes, a square and a triangular cuvette. For both types of cuvettes, the maximum RLS intensity peak was recorded at a wavelength of 420 nm because such a peak originates from the emission of the bandgap transition in the TiO2 structure and does not depend on the geometry of the cuvette used. The intensity of this maximum peak was correlated to the DF values using a similar exponential equation to that obtained for the DLS data. The R 2 value of the maximum RLS intensity peak was 0.97 when the triangular cuvette was used. On the other hand, using the square cuvette led to a poor correlation, which may be explained by the overshadowing of particles to interior volumes of the concentrated suspension sample in the cuvette. The triangular cuvette was further used throughout the rest of the investigations for mixed ink suspensions. For mixed ink suspensions, a poor correlation was found between the maximum peak intensity values and the volume percent of the milled ink in the mixed ink samples. This indicates that RLS is still not a sensitive technique to differentiate between average sizes of TiO2 particles compared to DLS measurements, which showed a strong linear correlation between z-average values and the volume percent of the milled ink (R2 = 0.97). For spiked ink suspensions, the maximum peak could be correlated to the weight percent of the spiking suspension using an exponential growth function with an R 2 value of 0.94. The exponential growth curve shows a plateau beyond 0.2 wt.% for the spiking suspension. This shows that RLS can be sensitive to the presence of a few large particles in suspension; however, a II further increase in the concentration of oversized particles did not result in a corresponding increase in the value of the maximum RLS spectra intensity peak. This can be explained based on the overshadowing of larger particles to each other in suspension leading to weak or no contribution from the shadowed large particles to the RLS spectra. On the other hand, the Z-average obtained from DLS measurements showed an exponential increase in correlation with the weight percent of the spiking suspension, reflecting the sensitive nature of DLS. In summary, RLS was found to be a sensitive technique for the concentration of single ink suspensions and low weight percentages of spikes suspensions when the triangular cuvette was used. For highweight percent spiked suspensions, and mixed ink suspensions, RLS was not assensitive as DLS. To overcome the overshadowing problem in RLS, the design of the cuvette itself, the path length and probably the position of the detector needs to be investigated, which can be the topic of future studies.21 0