Carlo Simon

Business process design by view integration

Even though the design of business processes most often has to consolidate the knowledge of several process stakeholders, this fact is utilized only to a limited extent by existing modeling methodologies. We address this shortcoming in this paper by building an analogy between database schema design by view integration on the one hand and process modeling on the other hand. In particular, we specify a method for business process design by view integration starting from two views of a process as input. We identify formal semantic relationships between elements of the two process views which are then used to calculate the integrated process model applying the merge operator. Finally, the integrated model is optimized using reduction rules. A case study with two EPC business process models from the SAP reference model demonstrates the applicability of our approach.

Integration of Multi-attributed Negotiations within Business Processes

For the integration of electronic negotiation systems within information systems, it is essential to model both using the same modelling paradigm to avoid frictions. We develop a generic model of electronic negotiations using Petri nets as a formal base focussing especially on the underlying processes. We introduce a negotiation scenario from which we derive the relevant processes, protocols and information objects, explaining the motivation for negotiations as well. Our approach is modular and allows an extension in various dimensions – however in this paper we concentrate on the idea of integrating electronic negotiations within business processes. As such, our models can be used as formal guide for integrating negotiation environments within workflow management systems and for simulating and verifying electronic negotiation scenarios.

Timestamp nets in technical applications

Timestamp Petri nets, introduced in this paper, offer a new method to deal with time critical problems in the field of automation of manufacturing systems. To each token in a timestamp net a timestamp is assigned, which denotes the time when the token was put on its place. In those nets intervals are assigned to the incoming edges of transitions, which describe the permeability of the edge relative to the token on the adjacent place. In timestamp nets it is possible that synchronizing transitions are not able to fire although they are supplied with tokens sufficiently, because their incoming edges are not permeable simultaneously. In this case we say the transition got timewise stuck. In this paper it is examined how transitions of a timestamp net are getting timewise stuck. Based on a symbolic analysis, these investigations can be reduced to solving systems of linear inequalities. The method can also be used to determine parameters for a timestamp net in order to prevent transitions from getting timewise stuck. We show the methods applicability by the dynamic model of a small technical plant as an example. Forbidden states of the uncontrolled system are described by transitions which can get timewise stuck. We use the method to determine time parameters of a controller, which ensures that forbidden states in the controlled system are unreachable.

Using Parameterized Timestamp Petri Nets in Automatic Control

In the following sections, we describe a method to deal with time critical problems in the field of automatic control of manufacturing systems. The behavior of a technical system is represented by Timestamp Petri Nets. With the aid of a symbolic analysis of such nets we generate a linear optimization problem from a system of inequalities. Their solutions imply time parameters for software controllers which avoid the occurrence of dangerous situations. We show the applicability of the method with a small example where unknown time parameters of a controller have to be determined in order to avoid forbidden states of the controlled system.

Initiating eLearning via Workflow Management

Both eLearning and Workflow Management Systems are widely used today to support Content Management. Workflow Management is designed to organise office processes in as optimal a way as possible by strictly structuring work, while eLearning enables a very flexible approach to the learning of new skills or information. In this paper, we suggest the integration of eLearning into Workflow Management, so that a demand for learning is registered automatically by the Workflow Management System, and is delivered via the Internet to provide a fully distributed solution for today’s organisations. Such a demand exists, for example, when an employee has to conduct a certain task for the first time. With the aid of a Learner Management System this tailored learning can be configured in a maximally efficient way with respect to each learner’s prior knowledge. We are currently testing our results in cooperation with one of the largest German insurance companies.