In this paper we introduce our NEPOMUK-based Semantic Desktop for the Windows platform. It uniquely features an integrative user interface concept which allows a user to focus on personal information management while relying on the Property Projection agent for semi-automated le management.
In recent years, mobile cloud computing [
Di erent devices and applications often come with their separate methods of organizing and storing information. Thus, considerable e ort has to be made to represent a single piece of information in multiple systems. In our case, the ISWC 2014 conference is being represented in ve di erent entities: a calendar event, a shared folder in the hierarchical le system, a notes list, a bookmarks folder and a task list.
There is a need for active support by computers in the creation and ltering
process of personal and group information. It has to provide a consolidated view
on data and blend the boundaries between workstations, mobile devices and web
services. Semantic Web technologies, speci cally the Semantic Desktop [
The application's dashboard is shown in gure 1. It serves as an entry point into exploring resources and provides quick access to resource collections (i.e. documents, pictures, events, etc.) and the local le system. Most prominently, it features an activity control (agenda and journal) which allows a user to plan into the future. Because future activities also serve as containers for les and related information, the dashboard provides quick access to all resources which are relevant to the user at a certain time.
Moreover, all resources can act as containers for relevant les and information. The displayed relations in the resource view can be hyperlinks to other resources, which enables browsing for interesting les and information. In order to assist a user in adding reasonable relations to a newly created resource, the Organiser actively analyzes the resource's properties and provides suggestions; such as to relate a collection of pictures to an event if they were taken at the time of the event. A user may accept or decline those suggestions.
Another feature of the resource view is, that it does not only consolidate already existing relations, but it also o ers the ability to create new content. When adding new les, such as o ce documents, a le system path is being generated from the metadata of the le and the context of the resource it was created in. 2.1
The hierarchical le system is the de facto standard for organizing and sharing les in a productive computing environment. In order to support a soft transition away from the static le system as a primary means of organizing and browsing les, we have developed the Property Projection method: A Semantic Web agent that is capable of learning how resource metadata is being projected into the path component of a URI, either by analyzing existing le systems or through interactive user input ( gure 2).
Once a projection schema has been learned, the agent can suggest storage locations for les being created in the context of a resource. This allows a user to shift from working with the static le system folders to working with resources such as contacts, events, notes or tasks that have temporal relevance to his or her activities.
The agent can formalize the schematic generation of URIs using the Property
Projection Ontology. Based on the Path Projection Ontology [
The Organiser is implemented using Trinity, our Semantic Web application development platform for .NET/Mono. It features a Semantic Object Mapping mechanism that allows to de ne an object oriented abstraction layer on top of a RDF triple store. This layer promotes the use of common development methods, proven application design patterns, and signi cantly increases the compatibility to existing APIs.
Although the Organiser's user interface is currently implemented using WPF, the consequent use of the MVVM design pattern allows for reimplementation using other technologies such as HTML and JavaScript. The interface is laid out in such a way, that it can be used on touch screens and may be scaled down to the resolution of current smartphones.
Metadata from the le system and cloud services is gathered in the background by Ubiquity, a metadata extraction and synchronisation service. All changes to the extracted resources made in the Organiser are mirrored back to the metadata of the respective resource. 3
The Organiser concept was re ned over multiple iterations and the software is nearing completion. Only nal usability tests and some connectivity and format extensions are missing.
A focus in the future is to implement the Organiser for mobile devices like Tablets and Smartphones. Because they accompany the user most of the time, we want them to act as a conduit to bring the seemingly virtual planning and organisation of the desktop into the everyday world of the user. Achieving a convergence of the user's data on mobile devices and the Desktop PC can lead to device independent productivity.