## 5 Execution  
The utility was coded using Microsoft's VB.NET and ESRI's ArcObjects framework, embedded within ArcCatalog as a dynamically linked library and exposed as a custom button within the application toolbar. Data instantiated as feature classes within the folder-geodatabase hierarchy are selected individually within the application's file browser and the tool is engaged. Harvesting and extraction routines, initiated from a form interface, together compute metadata elements for display within the form where they are made available for quality control and update prior to final output \begin{table}
\begin{tabular}{|c|c|} \hline
**Guideline** & **Seed source** \\ \hline What the dataset depicts & Alternative Title \\ \hline Area of coverage & Extent \\ \hline Period of coverage and frequency of update & Date, Frequency of update \\ \hline Data capture scale / resolution & Spatial Resolution \\ \hline Data capture method & capture\_process \\ \hline Suggested uses for data & Topic \\ \hline Category of features depicted & Subject \\ \hline Details of limitations in data & - \\ \hline Data linkages & Feature ID field \\ \hline Data originator(s) / editor(s) & Originator, origin, editor \\ \hline Data model & Spatial representation type \\ \hline Data format & Data format \\ \hline Data series & Sibling feature classes \\ \hline \end{tabular}
\end{table} 
Table 4: Guidelines for completing abstract content (adapted from recommendations published by Gigateway at [[http://www.gigateway.org.uk/metadata/standards.html/](http://www.gigateway.org.uk/metadata/standards.html/)]([http://www.gigateway.org.uk/metadata/standards.html/](http://www.gigateway.org.uk/metadata/standards.html/))). (Figure 4). Pre-formed metadata items are harvested from ArcCatalog's XML store using XPath expressions that allow referencing of specific elements. These expressions are read from a rudimentary crosswalk file that not only details the individual element sources within the application's XML metadata repository but also describe (in XPath) where form values will be written to within the XML-formatted GEMINI output document. Initial population routines return all elements in the event of prior completion; further routines may be executed selectively where elements are incomplete or require revision. Elements are computed from feature metadata content at run-time, referenced via their corresponding field names; routines index, summarise and identify maxima and minima according to the GEMINI element they contribute to. Dataset geometry is overlain with the incorporated reference layers to generate boundary names that are then added to the _Extent_ field and later used to seed the _Abstract_ entry. The application extracts elements from the storage hierarchy by parsing the dataset path and assigning its constituent tokens to form fields according to a path - element lookup table. Pre-authored content templates held within the file system as XML are harvested on the basis of active username, the contents of which are again addressed using XPath. Seeding of abstract content is  
Figure 4: An overview of approach’s routines, the metadata sources on which they operated (assisted by its associated auxiliary object). Computed values are displayed on a form interface where they may be modified by hand prior to validation and eventual output. performed as a penultimate event once other fields have been populated; contributing elements are harvested directly from the form and passed to the abstract field where they are elaborated upon manually. Metadata records are output as XML files once they have been evaluated and timestamps to actualise the _Date of Metadata update_ element have been applied. Metadata passing validation may now be exploited as surrogates for the data they depict, whether locally or following contribution to an off-site repository. Providing support for visualisation may be implemented by combining the metadata output operation with the conversion of the active dataset to an intermediary web portrayal format.