Many researchers have addressed the demands of knowledge intensive processes and often propose a data-oriented work ow approach. Others use ontologies in the periphery of work ow management systems to achieve di erent kind of contributions, while just a few research utilize the ontology for a semantic process de nition. This paper introduces a new approach which combines both perspectives to de ne an ontology- and data-driven business process model. The data-driven process characteristic is formed by a metamodel, placed in the base-ontology as the core of the conceptualization. These core concepts are expanded by more speci c concepts to build a domain oriented framework for the enterprise and process knowledge. Aligned with an example, we will explain how process de nitions are represented in the knowledge store and examine the gradual transition of an executable process instance. As a result, the ODD-BP approach takes advantage of a declarative data-oriented process model regarding exibility, while the semantic process de nition reduces ambiguity and builds the foundation to drive the process execution through inference mechanisms.
Compared with the established and well known BPMN approach, the new
approach introduced with this paper appears to be odd, but despite this
coincidence, ODD-BP stands for ontology- and data-driven business process approach.
The motivation arises from the research about knowledge intensive processes
(KiPs) with its data-oriented character [
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Arti cial intelligence (AI) in all its facets and across the di erent kind of
technologies are discussed in a wide range of use-cases as well as it is in the focus
of research in the BPM-context. No matter if an AI contribution is delivered by
the work ow system itself or by an external agent, when it comes to a division of
labour between human- and cyber actors, the process must be described without
ambiguity and understandable for all process participants. An ontology is the
perfect tool to achieve this requirement and can be used for a semantic process
de nition according to Fellmann [
The combination of both leads to an ontology and data driven ODD-BP approach as it is described in this paper. The data-driven character is formed by a metamodel de ned in the base-ontology as the core of the conceptualization. Aligned with our research project SEMANAS3, we examine the demands of knowledge intensive process in the domain of agricultural grant applications and expand the base-ontology by a domain-ontology focused on this speci c use-case.
Section 2 is referring the foundations of our work, while section 3 introduces the metamodel for our new approach. The application of the metamodel is described in section 4, while additional transition rules expand the conceptualization to ensure a valid execution of process instances. Section 5 gives a short insight into our current development of a process design-tool. With the conclusion in section 6, we give an outlook about the possibilities and advantages of the ODD-BP approach and our future work. 2
Business Process Model and Notation (BPMN) is currently the de facto
standard for designing and describing business processes world-wide. In the center
of this approach reigns a control- ow coordination of process steps (activities).
A less restrictive, but still activity-centric perspective is provided by
constraintbased approaches [
With view to these insights, several new approaches were brought up during
the last decade, putting the data into the center. The case handling paradigm [
Beside the examinations of di erent work ow models and principles, the
possibilities of semantic information systems in the domain of BPM are matter of
current research as well. S-BPM introduced a subject-oriented modeling scheme,
where sentences with subject, predicate, object are used to describe general
interactions between process actors [
The research about semantic formalizations within the eld of business
processes de nes the foundation for our work, but to the best of our knowledge,
no research addresses a semantic process modeling principle for a data-oriented
work ow approach to support the de nition and execution of knowledge intensive
processes. The general idea for this approach was already introduced through
our precedent work [
According to a wide range of publications [
Any work ow management system follows a metamodel, usually implementing one of the work ow-approaches mentioned in section 2. From a most fundamental perspective, all WF-approaches have in common, that they use a set of activities to achieve a speci c goal. The metamodel de nes the kind of process elements and their possible interactions and based on this model, a process de nition (PD) is speci ed for each kind of process goal, acting as a blueprint for process instances (PI) which can be executed to achieve a speci c goal of a certain kind.
All established work ow approaches follow this general WfMS-structure built on a metamodel, process de nitions and process instances (Fig. 1). The knowledge store (KS) is the combination of the ontology (T-Box) as the conceptual fundament and the triple store (A-Box) as the data storage. The base ontology de nes the metamodel 1 of the ODD-BP approach, it is domain independent and will be introduced in detail in 3.2. The domain ontology expands the conceptualization by de ning general valid concepts and relations of a domain. Further ontologies can expand the conceptual knowledge, like a document ontology, and form together the enterprise ontology, the fundament 2 of all process de nitions and process instances. A process de nition or a process instance is de ned by a set of linked individuals according the concepts and relations of the metamodel. Such a set represents a process graph and is stored as triples 3 in the A-Box. 3.2
The base-ontology de nes all concepts and relations to build the metamodel of the ODD-BP approach. The most fundamental artifacts of a process are Tasks, Dataobjects, Documents and Actors. Individuals of these concepts can be connected with an individual of the class Process through a contains or involves relation, as it is shown in Figure 2.
The mentioned artifacts are usually represented in one or another way in all work ow approaches. The speci c character of a metamodel is manifested by the kind of relations between these artifacts and in this case the data-oriented character of the ODD-BP approach is created by the relations between Tasks at the one side and Documents, Dataobjects and Attributes on the other side.
According to this metamodel, a Document can be demanded by a Task as input or a Task can produce a Document as the outcome of its execution. Analog to this, a Dataobject or an Attribute can be required by a Task as input or a Task can deliver such an element as output. The deeper meaning of Dataobject and Attribute will be explained more in detail in the following, but the general importance of data for a process execution is obvious.
Unlike these direct relations between the named concepts, the possible relations between Actors and Tasks are not de ned in a direct manner, but through specialized concepts. This allows a precise de nition of di erent kind of Actors and Tasks and their individual relations. Corresponding to this, a cyber actor (labeled as Agent ) can perform a System Task. A Role can just be assigned to a User-Task, while a User can execute such a User-Task, if the User is allowed to play the corresponding Role.
All in all the metamodel de nes, how a process can be designed and executed and these general rules are the same for process de nitions PD and process instances PI, which are de ned as a specialization of the concept Process. A process is modeled and described by individuals of the introduced concepts and by links between these individuals according the relations of the base ontology. 3.3
The general data-orientation of the metamodel can be seen by the manyfold
relations between Task and the data-carrying elements Dataobjects, Attributes
and Documents, in certain ways similar to artifact centric approaches [
Usually an information system organizes data about the real world with entities and relations. With view to databases, entities are managed as entries into a table, while a knowledge store is managing entities as individuals of a certain class. Such an individual represents an object of the real world, while its objectcharacteristics are stored as data-properties of the individual. This realization lacks in expressiveness, as the knowledge store can not express dependencies between tasks and data-properties and thus, the data-properties could not be used to drive the process.
This leads us to a conceptualization in which object-characteristics are represented through a separate concept, Attributes. They can be understood as key-value pairs, while an individual of this type is representing a single characteristic of an entity. With view to the example shown in Fig. 3, the individual Person is a dataobject to represent a speci c person in the real world. The birthdate and the adult state are represented by 2 separate individuals of the base-type Attribute, linked with Person through a consist of relation.
Assuming that a system task Is Adult can decide autonomously if a Person can be seen as adult or not. The relation between dataobject and task would usually just be expressed at an abstract and more general level 1 . Through the additional conceptualization, the relation between the system task Is Adult and the Attributes 2 can be modeled more in detail. This o ers a more speci c process de nition which allows to deduce the executability of tasks by an inference engine using the linked (input-)attributes with a required by relation. Beside the pure executability, such activities can deliver a more or less important process contribution to achieve a process goal which can be deduced using the linked (output-)attributes with a delivers relation.
Beside the entities itself, an information system also allows to express relations between entities. The base-ontology (Fig. 2) de nes two di erent basetypes to express such relations. The has a relation is intended to de ne any kind of global valid relations between entities. Within a further conceptualization through a domain ontology, specializations of the has a relation can be used to form an enterprise information model, equivalent to an ER-model of a database. The composed by relation is the prototype of a more process dependent combination of entities, not valid from a general perspective, but valid and required within a process context. It can be used to combine di erent kind of dataobjects for a process de nition and process execution. 3.4
Data can come from di erent sources like an information system, from a user or cyber actor (through a process or system task) and by documents, which usually means data-exchange with external systems or users. From this perspective, a document can provide dataobjects (Fig. 3) within a process context. According the introduced design to represent entities, a document can also provide attributes of dataobjects. These provide relations are also introduced by the base ontology (Fig. 2) and build the foundation for a semantic integration of documents into a process context. This topic is object of our current research and expands the possibilities of the ODD-BP approach even further. 4
The introduced metamodel de nes the vocabulary, which allows a process designer to express a process de nition for a certain process goal. The data of process de nitions and process instances as well as any data of the information system is part of the knowledge store and is persisted as triples in the triplestore, the A-Box. Since any process-element within a process de nition is just used to form a process template, these elements are placeholders and with view to a process instance, such placeholder elements will be replaced by meaningful elements during the process execution. To express this, the base-ontology (Fig. 2) also de nes a placeholder concept. Any process-element of a PD is represented by an individual assigned to one of the introduced concepts (task, dataobject, attribute, document) and additionally assigned to the placeholder class. This serves the inference mechanism to deduce the executability of activities as we mentioned before and which will be addressed in detail by a separate paper. 4.1
A process instance is initially nothing else than a copy of a process de nition with all its placeholder elements. Along the execution, the process instance performs a gradual transition from a process description de ned only by placeholder elements to a nal process state, where some or all process elements are meaningful elements. This gradual transition must follow some rules, but since the process descriptions of PD and PI are de ned by a set of individuals in the ABox, the rules can not be expressed using the conceptual layer of the knowledge store. In the following we will introduce these rules which de ne valid structural changes between a modeled process de nition and corresponding executed process instances. 4.2
A PD de nes a template to achieve a process goal like an application for a group event. In such a PD, a single individual of the classes dataobject and placeholder is representing the applicants, not knowing how many applicants will nally participate in a PI. To express this aspect of a multi-instanciation, the metamodel must o er the option to de ne the cardinality for each process element (PE). Since the placeholder PEs will be replaced during the process execution, the right place to persist the possibilities of the cardinality is at the link between the individuals of the process p and the process element pe. For this purpose, the contains relation is expanded by an annotation, which allows each link of this type to de ne the cardinality by a list with 2 numbers (n; m). { n 2 N0 de nes the minimum occurrence of a process element, while n = 0 de nes an optional occurrence within a PI. { m 2 N0 de nes the maximum occurrence of a process element, while m = 0 de nes an unlimited occurrence within a PI. { In the following, the cardinality will be expressed with an additional label at the contains relation as: p co(nnt;amin)!s pe
The multi-instanciation only de nes the possible occurrence of PEs. It tells nothing about the way, how such PEs interact with each other. This requires a further extension to express the intended transitions between PEs. 4.3
According the metamodel, Tasks, Documents and Dataobjects are connected with a Process through the contains relation. The interplay between individuals of these three concepts are de ned by the ve relation types provides, demanded by, produces, required by and delivers. Analog to the ontology, two connected process elements can be seen as a process statement with subject, predicate and object, while subject and object are individuals of the three mentioned concepts and predicate is a link of the ve mentioned relations. Such a process statement de nes an action (according the predicate) from a subject to the object. Since subject and object can be de ned with a di erent cardinality, the predicate must be extended with an annotation how the multi-instanciation can be processed to perform the transition from placeholder PEs to meaningful PEs. We can di erentiate in three transition rules: { expand: Each subject can result (along the predicate) in one or many objects. { maintain: Each subject can result (along the predicate) in exactly one object. { join: All subjects can result (along the predicate) in exactly one object. { In the following, the transition rules will be expressed with an additional label at the predicate as: pe (tranpsrietdiiocnaterule!) pe
As an example, Figure 4 shows a small process segment of a group application with di erent cases of multi-instanciation and transition rules. The left side presents the process de nition, where the links of the contains relation are annotated with the de nition for a multi-instanciation, while the other links are annotated with the transition rules. The PD de nes, that exactly one (1:1) Group Application is allowed, it allows at least 2 and a maximum of 6 Persons (2:6), any number of Is Adult tasks and just exactly one task Group Total Age. These four process elements are linked through provides and required by relations with the three di erent transition rules (expand, maintain, join).
The right side presents a corresponding process instance, where all process elements are transformed from placeholder PEs to meaningful PEs, according the introduced rules. The Group Application has provided two Persons, which ful lls the demand of the contains relations and follows the expand transition rule. It is required, that each Person must be an adult and the maintain transition rule is de ning, that for each Person an own Is Adult task must be executed. Additionally, the total age of the group is needed, which is why both Persons are linked with just one Group Total Age activity according the join transition rule. 5
The metamodel de nes the vocabulary to describe a process and through the introduced rules regarding multi-instantiation and transitions, also the semantic dependencies between process elements can be expressed. For a practical use and to design and execute ODD-BP de nitions and instances, a modeling tool is required.
As a rst step towards a POIS, we started the development of a graphical
toolset on a web-based client-server architecture. It aims to support a process
designer by utilizing the metamodel to turn the ontological restriction into an
easy to use graphical user-interface. Beside this, it also sets the outer ontological
restriction into action.
AI technologies in general can deliver a wide range of contributions within the
eld of business processes and even semantic information systems can be used in
di erent ways. The introduced ODD-BP approach combines the principles of
semantic process de nitions [
One central motivation is to utilize the ontology and the data-oriented metamodel to drive the introduced approach, which leads us to the acronym ODD-BP approach. This requires a precise de nition of the interplay between data and activities and we have shown, that the conceptualization of Attributes through the metamodel expands the expressiveness of a process de nition and de nes the base for di erent kinds of cyber process contributions. Within a separate paper we will show, that a process de nition on base of the ODD-BP approach can be used to deduce the executability of activities. Further more we will show, that even the relevance of an activity can be deduced according its contribution to reach prede ned process goals and process milestones.
There is a wide range of further possibilities to take advantage of the
ODDBP approach. As such, the explainability of the inference while deducing
executable tasks could be utilized to adapt a process instance according an identi ed
problem. The semantic process de nition could also be used for an adaptive
process visualization as it was already introduced [