Using Document-centric Information Systems (IS ) in an Enterprise is very common nowadays: the IS s serves as the basis for storage of data, elements of business processes and they provide a exible communication protocol between Web-services too (XML-like documents). Designing work- ows, object hierarchies and much more business-related entities can be done by various types of models (UML, BPMN, Petrinets). The models and their relationships can be represented mostly through the combination of the Zachman and the TOGAF framework [1, 2] in our case. To assist the designing, analyzing, validating and optimizing steps during model creation, we suggest a generic modeling approach based on the generalized hypergraphs. This helps avoid inconsistencies between the models without using any extra transformations or cross-checks [3]. In our proposed designer tool we use the HypergraphDB which is a graph database providing every advantages of the generic hypergraphs [4, 5]. To extend the object-de nition and rule formalism we use description logics beside the hypergraph formalism.
veri cation of consistency the models that were placed in the architecture. The model re nement and extension are carried out by systematic design principles that are under the supervision of constraints that are deduced from the assumptions of consistency and integrity. The set of models ordered into architecture framework yields support for operational function in the production time of an IS.
In Section 2, we introduce these particular models through previous researches in literature, in Section 3 we de ne some notion for a better understanding about hypergraphs, in Section 4 we explain the chosen databasesystem for our model and Section 5 provides conclusions and possible future work. 2
The Web-based and Web Information Systems are the typical examples that make extensive use of the various
document formats. The emphasis on Web technologies slowly diminished as the application of Web technology,
de nitely at user interfaces, became commonplace. A systematic design approach to construct web-based
applications is discussed in. The method explained in [
An Information System supports business processes (Business Process Modeling, BPM ) within an enterprise
and is tightly coupled to other IS usually. A fairly standard way to model business processes is either the
application of Business Process Modeling (BPM) methods, or using Petri-nets. The Information Systems can also
be perceived as a structure with underlying databases for structured, semi-structured (XML-based, eXtensible
Markup Language) as well as unstructured documents . The documents play important role at the interface, at
interaction level and at core activities of data processing. The integration level and the degree of reconciliation
between Business Processes and organization can be analyzed on the base of ontologies and semantic approaches
[
There were some previous papers and researches that tried to put the before-mentioned approaches into a
uni ed framework by essentially semi-formal way [
The Enterprise Architecture framework is provided by a mapping across Zachman ontology and TOGAF
framework [
Since our proposed approach of the uni ed modeling is based on a generalized hypergraph theorem, it induces a need for a storage with this capabilities. From the technological point of view, there are a lot of graph-based database systems. The suggested HypergraphDB is an open-source project which is based on the knowledge management formalism known as directed hypergraphs. 3
Hypergraphs. There are several conceptual formalization that are mentioned in other papers [
The hypergraphs as mathematical structure seems to be suitable for representing the interrelationships among
the models, views, viewpoints, perspectives, and the overarching documents and business processes [
To gain insight into the hypergraphs we start with the basic de nitions in order to apply for depicting the before-mentioned complex relationships.
De nition 1. A hypergraph H is a pair of (V,E) of a nite set of V = fv1; v2; :::vng and a set E of nonempty subsets of V. The elements of V are called vertices or nodes, the elements of E are called edges [4].
De nition 2. Generalized or extended hypergraphs. The notion of hypergraph may be extended so that the hyperedges can be represented { in certain cases { as vertices, i.e. a hyperedge e may consist of both vertices and hyperedges as well. The hyperedges that are contained within the hyperedge e should be di erent from e [4].
Considering a document model, a proper document type hierarchy can be interpreted as a ordered sub-set of the hyper-edges. In a document subpart hierarchy, a speci c subpart of document may be denoted by a vertex within a particular hyper-edge that describes this document that contains the subpart, although that subpart as a vertex may include a document type hierarchy that can be depicted by a hyperedge.
De nition 3. A directed hypergraph is an ordered pair where V is a nite set of vertices and !E is a set of hyperarcs with a nite index-set I. Every hyperarc !ei can be interpreted as an ordered pair ! H =
V; !E = f !ei : i 2 I g ; !ei = e!i+ = (ei+; i); e!i = (i; ei ) ; (1) (2) where ei+
tail of !ei , while elements of e!i are called head [4].
The potential implementations of hypergraphs in a hypergraph database allows for linking attributes to
vertices, even more to hyperedges. The target domain, namely documents and model of Information Systems
within organizations, contains complex n-ary relationships. The hypergraph provides the opportunity to represent
recursive construction, to describe logical relations, to store compound structures along with their values and to
follow variable lifetimes across various processes. [
The HypergraphDB is an extensible, portable, distributed open-source data-storage mechanism. It is a
graphdatabased designed speci cally for arti cal intelligence and semantic web projects, however because of it general
mindset, it is a perfect tool to represent heterogeneous relationships between di erent types too. The following
key facts are convincing enough to use the HypergraphDB as tool to store our model [
Data types are managed by a general, extensible type system embedded itself as a hypergraph structure. Types are themselves atoms as everybody else, but with a particular role.
The storage scheme is platform independent and can thus be accessed by any programming language from any platform. Low-level storage is currently based on BerkeleyDB from Sleepycat Software. Size limitations are virtually non-existent. There is no software limit on the size of the graph that are managed by a HyperGraphDB instance. Each individual value's size is limited by the underlying storage, i.e. by BerkeleyDB's 2GB limit. However, the architecture allows bypassing BerkeleyDB for particular types of atoms if one so desires.
The implementation is solely Java based. It o ers an automatic mapping of idiomatic Java types to a HyperGraphDB data schema which makes HyperGraphDB into an object-oriented database suitable for regular business applications.
Since there aren't any rst-party user interface for the HypergraphDB, the rs step to start using it was to
design and develop a middle-ware software which can create complete hypergraphs by creating the appropriate
nodes and edges based on various input. These inputs can be mostly XML-based descriptors - like OWL - but
can be also some custom, user de ned XML schema. In our case, we had a tool - written in C++ using the Qt
Framework [
To test the capabilities of the database, we created a hypergraph based on a business process. This process was rst designed in the above-mentioned tool, then the XML output was passed to the middle-ware. After the middle-ware nished the processing of the XML le it created the necessary nodes and the edges. Also utilizing the HypergraphDB e ciency the nodes and hyperedges can be labeled with custom JAVA classes, therefore the potential of the object-oriented class hierarchy is exploitable. 5
There is a bunch of aspects to analyze the relations among di erent model-types. For every designing step
mentioned before [
[3] Suh, N.P.. 2001. Axiomatic Design: Advantages and Applications. Oxford University Press, New York [4] Bretto, A. 2013. Hypergraph Theory: An Introduction. Springer.
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