| This dissertation presents a formal approach to modeling documents in a personal office environment, proposes a heterogeneous algebraic query language to manipulating objects (folders) in the document model, and investigates a predicate-driven document filing-system for automatically filing documents.; The document model adopts a very natural view for describing the office documents using the relational and object-oriented paradigms. The model employs a dual approach to classifying and categorizing office documents by defining both a document type hierarchy and a folder organization. Documents are partitioned into different classes, each document class being represented by frame template which describes the properties of the documents of the class. A particular office document, summarized from the viewpoint of its frame template, yields a synopsis of the document which is called frame instances. Frame instances are grouped into a folder on the basis of user-defined criteria, specified as predicates, which determine whether a frame instance belongs to a folder. Folders, each of which is a heterogeneous set of frame instances, can be naturally organized into a folder organization. This dissertation also proposes an algebra-based query language that gives full support to this heterogeneous property.; The global predicate of a folder governs the content of the folder. However, the predicates of folders (that is, global predicates) do not uniquely specify a folder organization. Then, we investigate the reconstruction problem: under what circumstance can we uniquely recover the folder organization from its global predicates? The problem is solved in terms of graph-theoretic concepts such as associated digraphs, transitive closure, and redundant/non-redundant filing paths. A transitive closure inversion algorithm is then presented which efficiently recovers a folder organization digraph from its associated digraph.; A document filing algorithm describes the procedure of filing a frame instance. However, the critical issue of the algorithm is how to evaluate whether a frame instance satisfies the predicate of a folder in a folder organization. In order to solve this issue, a thesaurus, an association dictionary and a knowledge base are then introduced. |
