Compositional Discovery of Workflow Nets from Event Logs Using Morphisms
This paper presents a modular approach to discover process models for multi-agent systems from event logs. System event logs are filtered according to individual agent behavior. We discover workflow nets for each agent using existing process discovery algorithms. We consider asynchronous interactions among agents. Given a specification of an interaction protocol, we propose a general scheme of workflow net composition. By using morphisms, we prove that this composition preserves soundness of components. A quality evaluation shows the increase in the precision of models discovered by the proposed approach.
In this work we consider modeling of services with workflow modules, which are a subclass of Petri nets. The service compatibility problem is to answer the question, whether two Web services fit together, i.e. whether the composed system is sound. We study complementarity of service produced/consumed resources, that is a necessary condition for the service compatibility. Resources, which are produced/consumed by a Web service, are described as a multiset language. We define an algebra of multiset languages and present an algorithm for checking the conformance of resources for two given structured workflow modules.
Process mining is a relatively new field of computer science which deals with process discovery and analysis based on event logs. In this work we consider the problem of discovering workflow nets with cancellation regions from event logs. Cancellations occur in the majority of real-life event logs. In spite of huge amount of process mining techniques little has been done on cancellation regions discovery. We show that the state-based region algorithm gives labeled Petri nets with overcomplicated control flow structure for logs with cancellations. We propose a novel method to discover cancellation regions from the transition systems built on event logs and show the way to construct equivalent workflow net with reset arcs to simplify the control flow structure.
This book constitutes the proceedings of the 37th International Conference on Application and Theory of Petri Nets and Concurrency, PETRI NETS 2016, held in Toruń, Poland, in June 2016. Petri Nets 2016 was co-located with the Application of Concurrency to System Design Conference, ACSD 2016. The 16 papers including 3 tool papers with 4 invited talks presented together in this volume were carefully reviewed and selected from 42 submissions. Papers presenting original research on application or theory of Petri nets, as well as contributions addressing topics relevant to the general field of distributed and concurrent systems are presented within this volume.
Despite all the advantages brought by service-oriented architecture (SOA), experts argue that SOA introduces more complexity into information systems rather than resolving it. The problem of service integration challenges modern companies taking the risk of implementing SOA. One of important aspects of this problem relates to dynamic service composition, which has to take into account many types of information and restrictions existing in each enterprise. Moreover, all the changes in business logic should also be promptly reflected. This chapter proposes the approach to solution of the stated problem based on such concepts as model-driven architecture (MDA), ontology modelling and logical analysis. The approach consists of several steps of modelling and finite scope logical analysis for automated translation of business processes into the sequence of service invocations. Formal language of relational logic is proposed as a key element of the proposed approach which is responsible for logical analysis and service workflow generation. We present a logical theory to automatically specialize generic orchestration templates which are close to semantic specification of abstract services in OWL-S. The developed logical theory is described formally in terms of Relational Logic. Our approach is implemented and tested using MIT Alloy Analyzer software.
These are the proceedings of the International Workshop on Petri Nets and Software Engineering (PNSE’13) and the International Workshop on Modeling and Business Environments (ModBE’13) in Milano, Italy, June 24–25, 2013. These are co-located events of Petri Nets 2013, the 34th international conference on Applications and Theory of Petri Nets and Concurrency.
PNSE'13 presents the use of Petri Nets (P/T-Nets, Coloured Petri Nets and extensions) in the formal process of software engineering, covering modelling, validation, and veriﬁcation, as well as their application and tools supporting the disciplines mentioned above.
ModBE’13 provides a forum for researchers from interested communities to investigate, experience, compare, contrast and discuss solutions for modeling in business environments with Petri nets and other modeling techniques.
This volume constitutes the proceedings of the 34th International Conference on Application and Theory of Petri Nets and Concurrency (PETRI NETS 2013). The Petri Net conferences serve as annual meeting places to discuss the progress in the field of Petri nets and related models of concurrency. They provide a forum for researchers to present and discuss both applications and theoretical developments in this area. Novel tools and substantial enhancements to existing tools can also be presented. The satellite program of the conference comprised three workshops, a Petri net course including basic and advanced tutorials and an additional tutorial on the work of Carl Adam Petri and Anatol W. Holt.
There have been implemented engineering and development of multi-agent recommender system «EZSurf» that performs analysis of interests and provides recommendations for the social network «VKontakte» users based on the data from profile of particular user. During the work process different methods and technological solutions have been analyzed with examination of their advantages and disadvantages. Besides of that the comparative analysis of analogous products has been held where the most similar is Russian start-up service - Surfingbird. Based on this analysis the decision of recommender system implementation and integration has been accepted. The feature of this system is that it uses social network “VKontakte” profile for user’s data collection and API of third-party services (LastFM, TheMovieDB) for an extraction of information about similar objects. Such an approach contributes into optimization of recommender system, because it does not require creation of its own object classification system and objects database. The functionality of multi-agent system was separated between three agents. First agent (Collector) collects user data from “VKontakte” profile using VK API. Second agent (Analyzer) collects similar objects from databases of thitd-party services (LastFM, TheMovieDB) that will be the criteria for further search of recommendatory content. For search and selection of information an agent (Recommender) that works as web-crawler has been implemented. System «EZSurf» can be exploited by the users of social network “VKontakte” in everyday life for time economy on web-surfing process. At the same time they will get recommendations on content that are filtered depending on preferences of every particular user.
Resource-driven automata (RDA) are finite automata, sitting in the nodes of a finite system net and asynchronously consuming/producing shared resources through input/output system ports (arcs of the system net). RDAs themselves may be resources for each other, thus allowing the highly flexible structure of the model. It was proved earlier, that RDA-nets are expressively equivalent to Petri nets. In this paper the new formalism of cellular RDAs is introduced. Cellular RDAs are RDA-nets with an infinite regularly structured system net. We build a hierarchy of cellular RDA classes on the basis of restrictions on the underlying grid. The expressive power of several major classes of 1-dimensional grids is studied.
The paper discusses a multi-paradigm approach to the modeling of Demand Responsive Transport systems. It contains a brief overview of issues which appear during modeling of such systems, considers various multi-agent architectures and describes some algorithms which can be used for modeling. Also the paper provides some details about previous investigations on this topic, in particular: a centralized model based on combinatorial auctions and a multi-agent based multi-layer distributed hybrid model. The aim of the paper is working out a sound solution based on a combination of these two approaches which would utilize “system of systems” engineering approach where layered architecture would help to deal with real-time issues and increase system’s reliability and combinatorial auctions would help with global search of the optimal solution. Such combination improves the efficiency and reliability of the system.