## 3 Results
### The GREYWARE Information System: Ontology Overview and Components
#### 3.1.1 Application Programs  
As mentioned above, Greyware uses commercial and free application programs for specific tasks. Some of these are of general use and common to most disciplines and non-specialized users such as Microsoft Office(r) [48] or Adobe(r) pdf maker [49]. Information is stored and shared through the commonly used online repositories Microsoft OneDrive(r) [50] and Dropbox(r) [51], allowing for collaborative execution.  
Figure 4: UML diagram of Greyware’s overview and components. Classes described by the Horai UT/Ac data model are represented in blue. Their relation with top-level entity-event ontologies [11; 35] are highlighted in green. Categories defined in pottery studies (and thus in domain or task ontologies) included in the Greyware data-modelling are represented in black and white. The central area shaded by the project’s interface identifies the processes developed in the classification chart shown in Figure 2 and the application programs used to perform research tasks. Process components included in the Greyware database are shaded in white.  
We should outline the application Protege (in its Version 5.5) [52] as an outstanding tool for ontology design. It allows for a high degree of interoperability by exporting and importing XML, RDF and OWL formats, and its extensibility via plugins and the usability of ontology libraries [29; 30] are highlights as well.  
Specific tasks in pottery analyses require a higher level of software specialization, but still, most of the applications are easily available. We used Claris Filemaker Pro(r) software (Versions 9.0 and 15.0) [53] for database design and management and several application programs for image processing and visualization. The CoreDraw Graphics Suite(r) [54] provides an interesting range of tools for image design and editing, and the free application XnView [55] offers an easy and intuitive interface for metadata creation. Micrograph capture and exploitation is carried out using the Olympus CellSens(r) basic software [56], capable of taking and processing high quality pictures from pottery thin-sections observed under the microscope.  
For data exploitation and processing graphic information systems, we use applications for statistical analysis, and graph processing software in addition to the database. QGs [57] is nowadays one of the most commonly used Geographic Information Systems in archaeology due to its public availability and wide ranging possibilities as a free software tool. Despite being a commercial version, MapInfo(r) GIS [58] is a simple and intuitive mapping solution as well, easy to use for non-experts in this domain. The Greyware system uses the software IBM SPSS(r) [59] for the statistical exploitation of compositional and morphometric data obtained from pottery analysis and the non-commercial option R. This is a free software environment for statistical computing and graphics, offering a wide range of possibilities for data exploitation and graph visualization and editing [60]. Flowcharts, matrices, UML diagrams and other plotting results are produced with the online software application Draw.io [61], used and stored through the OneDrive repository. The occasional use of more than one software application for specific tasks depends on the user's choice. It might be argued that the system makes much use of commercial software, and this is something to be improved in further versions. As advanced computer users, but not software developers, our choices were usually constrained by the use of widely extended commercial products. Nevertheless, as long as users keep tight to the File Classification Chart for the storing and managing of the files created, software applications are simple tools to achieve specific research goals and open data formats are fully compatible.