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From Declarative Processes to Imperative Models

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Nowadays organizations support their creation of value by explicitly defining the processes to be carried out. Processes are specifically discussed from the angle of simplicity, i.e., how compact and easy to understand they can be represented. In most cases, organizations rely on imperative models which, how-ever, become complex and cluttered when it comes to flexibility and optionality. As an alternative, declarative modeling reveals to be effective under such cir-cumstances. While both approaches are well known for themselves, there is still not a deep understanding of their semantic interoperability. With this work, we examine the latter and show how to obtain an imperative model out of a set of declarative constraints. To this aim, we devise an approach leading from a De-clare model to a behaviorally equivalent Petri net. Furthermore, we demonstrate that any declarative control flow can be represented by means of a Petri net for which the property of safety always holds true.
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... Alternatively, conversions to the same execution language can be obtained. However, the conversion turns out to be often intractable [50], or resorts to approaches that are too language-specific [51,52]. The latter has caused no previous work to apply existing techniques, either procedural or declarative, to mixed-paradigm models. ...
... In [51], Declare constraints are translated into equivalent Petri nets with weighted, reset and inhibitor arcs. In [50,13], regular expressions (REs) are used to define the semantics of Declare templates. Since REs and Monadic Second ...
... Other mixed-paradigm solutions exist as well, such as BPMN with Declare (BPMN-D)[52]. Furthermore, conversions between both types of models have been introduced, e.g., from Declare to Petri Pre-print copy of the manuscript published by Elsevier identified by doi: 10.1016/j.is.2020.101685nets[50,51]. Nevertheless, both approaches can be converted to models that are compatible with the proposed conformance checking technique. ...
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Mixed-paradigm process models integrate strengths of procedural and declarative representations like Petri nets and Declare. They are specifically interesting for process mining because they allow capturing complex behavior in a compact way. A key research challenge for the proliferation of mixed-paradigm models for process mining is the lack of corresponding conformance checking techniques. In this paper, we address this problem by devising the first approach that works with intertwined state spaces of mixed-paradigm models. More specifically, our approach uses an alignment-based replay to explore the state space and compute trace fitness in a procedural way. In every state, the declarative constraints are separately updated, such that violations disable the corresponding activities. Our technique provides for an efficient replay towards an optimal alignment by respecting all orthogonal Declare constraints. We have implemented our technique in ProM and demonstrate its performance in an evaluation with real-world event logs.
... Alternatively, conversions to the same execution language can be obtained. However, the conversion turns out to be often intractable [50], or resorts to approaches that are too language-specific [51,52]. The latter has caused no previous work to apply existing techniques, either procedural or declarative, to mixed-paradigm models. ...
... In [51], Declare constraints are translated into equivalent Petri nets with weighted, reset and inhibitor arcs. In [50,13], regular expressions (REs) are used to define the semantics of Declare templates. Since REs and Monadic Second ...
... Other mixed-paradigm solutions exist as well, such as BPMN with Declare (BPMN-D) [52]. Furthermore, conversions between both types of models have been introduced, e.g., from Declare to Petri nets [50,51]. Nevertheless, both approaches can be converted to models that are compatible with the proposed conformance checking technique. ...
Preprint
Full-text available
Mixed-paradigm process models integrate strengths of procedural and declarative representations like Petri nets and Declare. They are specifically interesting for process mining because they allow capturing complex behaviour in a compact way. A key research challenge for the proliferation of mixed-paradigm models for process mining is the lack of corresponding conformance checking techniques. In this paper, we address this problem by devising the first approach that works with intertwined state spaces of mixed-paradigm models. More specifically, our approach uses an alignment-based replay to explore the state space and compute trace fitness in a procedural way. In every state, the declarative constraints are separately updated, such that violations disable the corresponding activities. Our technique provides for an efficient replay towards an optimal alignment by respecting all orthogonal Declare constraints. We have implemented our technique in ProM and demonstrate its performance in an evaluation with real-world event logs.
... We describe four examples that are frequently used for process mining, namely directly-follows 8 graphs, Petri nets, Declare constraints, and process trees [2]. It is well known that transformations exist between many of these representations [18,19,20] Directly-follows graphs. Event sequences can be modeled as a graph, where each node represents a type of event and arcs describe directly-follows relationships between these event types [2]. ...
... Event sequences can be described as a collection of rules by which 9 the underlying behavior is constrained. One such specific modeling language that uses LTL for describing event sequence data is Declare [23,20]. Table 2 shows a set of rules showing that constrain event sequences. ...
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... • Random Conjunction formulas combine 19 common LTL f formulas from [17,38] (see the first 19 patterns in Table 2) as random conjunctions in the style of [39] in two sets of 500 formulas: • Pattern Formulas 7 scalable patterns (see the last 7 patterns in Table 2) inspired by [40] up to length 100. The total number of generated formulas is 700. ...
... Declare Patterns From [17,38] sat* Existence a a must be executed at least once sat* Absence 2 ¬ (a ∧ a) a can be executed at most once sat* Choice ...
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... Therefore, in formal terms, from case 3 onwards, the behavioral rule that the sepsis triage occurs after the general triage abruptly decreases in the number and share of observations. Several rule languages with a rich spectrum of behavioral constraints have been proposed [27], [28], [29]. In rule languages based on linear temporal logic such as DECLARE, we can formally state that the rule ALTERNATERESPONSEpER Triage, ER Sepsis Triageq drops in confidence. ...
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... The benefit of using Declare constraints is that they cover both unary and binary relations, meaning they can also cover the behaviour of a single activity. Furthermore, the constraints' automata can be converted into Petri nets if desired [42,43]. ...
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... Another context in which one can investigate the applicability and adaptation of our approach is that of the models of behaviour expressing distributed systems invariants [42]. Finally, one can design new quality measures that relate arbitrary numbers of behaviours (not just behaviours of a specification and its execution log), e.g., to establish a basis for comparing results of various process querying methods [79], models of behaviour that summarise traces at varying levels of abstraction [43], and different behavioural representations [83]. ...
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