Getting started with Xemod
This article contains information about some basics of Xemod. It is meant to understand the way Xemod is set up.
Modeling enterprises with Xemod
Xemod is a modeling tool to create a model of an enterprise. In Xemod, the DEMO Methodology is the central approach for this. We assume that users have basic knowledge about DEMO.
Separation of model and representation
An important principle in Xemod is the separation between model and representation. A model contains the conceptualization of an enterprise. In order to communicate this conceptualization it is expressed, namely by means of symbols. Most convenient way to express a model of an enterprise is by means of diagrams. DEMO contains several of those diagrams (like Organization Construction Diagram, Process Structure Diagram) but also so-called 'tables' (like Bank Contents Table).
In the user interface of Xemod this separation is visible in the Project Explorer. The Project Explorer shows in the 'Representation' part all representations that are present in the project file (namely diagrams and tables for DEMO). The 'Model' part shows all elements (the so-called model facts) that together constitute the model.
Several representations can be defined on the same model and can express the same model facts. So for example the same actor role (which can be considered as one model fact) can be represented on several Organization Construction Diagrams.
(Background information on this subject can be found in chapter 7 'The Notion of Model' of the book 'Enterprise Ontology. Theory and Methodoloy' written by Jan Dietz.)
One model per project file
One Xemod project file contains one model. So one project file contains the conceptualization of one 'world'. This has as implication that one project file cannot contain two or more alternatives for e.g. the same process kind. It has also as implication that if a user models two 'worlds' inside one project file by means of assigning different ranges of codes to model facts, Xemod will not recognize the intended two models.
An important feature of Xemod is model verification. After a user has defined a model he can check whether it meets the conditions for a well-defined model. The verification can be done per DEMO aspect model or for the total model. If the verification brings errors to light, hints are provided how to solve them.