Process mining is a tool to extract non-trivial and useful information from process execution logs. These so-called event logs (also called audit trails, or transaction logs) are the starting point for various discovery and analysis techniques that help to gain insight into certain characteristics of the process. In this paper we use a combination of process mining techniques to discover multip...

A Markovian Petri net is a stochastic discrete event system frequently used for analysis and performance evaluation purposes. In the past, the fluidification has been proposed as a relaxation technique for avoiding the ”state explosion problem”. Following the same approach, in this paper a hybrid Petri net model is defined as a partial relaxation of an original Markovian Petri net. It is shown ...

Object-oriented programming [9], which treats objects as processes in execution, has shown significant effectiveness in distributed systems. This effectiveness is greatly influenced by how objects are assigned to nodes. In this paper, we present a colored generalized stochastic Petri net (CGSPN) model to analyze the behavior of object invocations when an assignment strategy is applied. The effe...

Energy use is becoming a key design consideration in computing infrastructures and services. In this paper we focus on service-based applications and we propose an adaptation framework that can be used to reduce power consumption according to the observed workload. The adaptation guarantees a trade-off between energy consumption and system performance. The approach is based on the principle of ...

Approaches to the state space explosion problem in Markovian modelling of concurrent systems are discussed. The emphasis is on structured model description techniques and model simpliication. In particular, it is shown that the exploitation of model symmetries has a potential to drastically reduce the size of the state space. The common features of diierent techniques described in the literatur...

Sensitivity analysis, i.e., the analysis of the eflect of small variations in system parameters on the output measures can be studied b y computing the derivatives of the output measures with respect t o the parameter. This paper presents an algorithm for parametric sensitivity analysis of Markov Regenerative Stochastic Petri Nets (MRSPN). MRSPNs are a true generalization of stochastic Petri ne...

We present a stochastic Petri net model of a replicated file system in a distributed environment where replicated files reside on different hosts and a voting algorithm is used to maintain consistency. Witnesses, which simply record the status of the file but contain no data, may be used in addition to or in place of files to reduce overhead. We present a model sufficiently detailed to include ...

Generalized resources are defined as multisets of Petri net vertices. Here places represent material resources (designated by tokens residing in these places). Transitions correspond to activity resources represented by transition firings. Two generalized resources are called similar if in any Petri net marking one resource can be replaced by another without changing the observable system’s beh...

Service Failure model is described by Stochastic Petri nets. Some of the service failure precisely corresponds to the confusion. Confusion is one of very important concept in the Petri nets. Because it appears to be difficult to obtain a “correct” implementation when emerges confusion in the Petri net system, it is not a good model when exists confusion. When we build some service failure and r...