Relational Algebra for In-Database Process Mining

The execution logs that are used for process mining in practice are often obtained by querying an operational database and storing the result in a flat file. Consequently, the data processing power of the database system cannot be used anymore for this information, leading to constrained flexibility in the definition of mining patterns and limited execution performance in mining large logs. Enabling process mining directly on a database - instead of via intermediate storage in a flat file - therefore provides additional flexibility and efficiency. To help facilitate this ideal of in-database process mining, this paper formally defines a database operator that extracts the 'directly follows' relation from an operational database. This operator can both be used to do in-database process mining and to flexibly evaluate process mining related queries, such as: "which employee most frequently changes the 'amount' attribute of a case from one task to the next". We define the operator using the well-known relational algebra that forms the formal underpinning of relational databases. We formally prove equivalence properties of the operator that are useful for query optimization and present time-complexity properties of the operator. By doing so this paper formally defines the necessary relational algebraic elements of a 'directly follows' operator, which are required for implementation of such an operator in a DBMS

Semantic business process management: a vision towards using semantic web services for business process management

Business process management (BPM) is the approach to manage the execution of IT-supported business operations from a business expert's view rather than from a technical perspective. However, the degree of mechanization in BPM is still very limited, creating inertia in the necessary evolution and dynamics of business processes, and BPM does not provide a truly unified view on the process space of an organization. We trace back the problem of mechanization of BPM to an ontological one, i.e. the lack of machine-accessible semantics, and argue that the modeling constructs of semantic Web services frameworks, especially WSMO, are a natural fit to creating such a representation. As a consequence, we propose to combine SWS and BPM and create one consolidated technology, which we call semantic business process management (SBPM

Workflow Provenance: from Modeling to Reporting

Workflow provenance is a crucial part of a workflow system as it enables data lineage analysis, error tracking, workflow monitoring, usage pattern discovery, and so on. Integrating provenance into a workflow system or modifying a workflow system to capture or analyze different provenance information is burdensome, requiring extensive development because provenance mechanisms rely heavily on the modelling, architecture, and design of the workflow system. Various tools and technologies exist for logging events in a software system. Unfortunately, logging tools and technologies are not designed for capturing and analyzing provenance information. Workflow provenance is not only about logging, but also about retrieving workflow related information from logs. In this work, we propose a taxonomy of provenance questions and guided by these questions, we created a workflow programming model 'ProvMod' with a supporting run-time library to provide automated provenance and log analysis for any workflow system. The design and provenance mechanism of ProvMod is based on recommendations from prominent research and is easy to integrate into any workflow system. ProvMod offers Neo4j graph database support to manage semi-structured heterogeneous JSON logs. The log structure is adaptable to any NoSQL technology. For each provenance question in our taxonomy, ProvMod provides the answer with data visualization using Neo4j and the ELK Stack. Besides analyzing performance from various angles, we demonstrate the ease of integration by integrating ProvMod with Apache Taverna and evaluate ProvMod usability by engaging users. Finally, we present two Software Engineering research cases (clone detection and architecture extraction) where our proposed model ProvMod and provenance questions taxonomy can be applied to discover meaningful insights

Tracking Federated Queries in the Linked Data

Federated query engines allow data consumers to execute queries over the federation of Linked Data (LD). However, as federated queries are decomposed into potentially thousands of subqueries distributed among SPARQL endpoints, data providers do not know federated queries, they only know subqueries they process. Consequently, unlike warehousing approaches, LD data providers have no access to secondary data. In this paper, we propose FETA (FEderated query TrAcking), a query tracking algorithm that infers Basic Graph Patterns (BGPs) processed by a federation from a shared log maintained by data providers. Concurrent execution of thousand subqueries generated by multiple federated query engines makes the query tracking process challenging and uncertain. Experiments with Anapsid show that FETA is able to extract BGPs which, even in a worst case scenario, contain BGPs of original queries

Constraint integration and violation handling for BPEL processes

Autonomic, i.e. dynamic and fault-tolerant Web service composition is a requirement resulting from recent developments such as on-demand services. In the context of planning-based service composition, multi-agent planning and dynamic error handling are still unresolved problems. Recently, business rule and constraint management has been looked at for enterprise SOA to add business flexibility. This paper proposes a constraint integration and violation handling technique for dynamic service composition. Higher degrees of reliability and fault-tolerance, but also performance for autonomously composed WS-BPEL processes are the objectives