1 Ontology-based Semantic Annotatoin of Process Template for Reuse Yun Lin, Darijus Strasunskas Depart. Of Computer and Information Science Norwegian Univ. Of Science and Technology

2 Agenda Problem Statements Proposed Approach – Semantic Annotation Ontological Basis and Meta-Model Mediator Semantic Annotation of Process Template Applications Conclusions and Future Work

3 Problem Statement A process template is abstracted from a process model instance for reuse purpose. Reuse of process templates improves the quality of process modeling by reflecting previous knowledge and experience. Process templates are stored in the distributed model repositories. Storage and retrieval of process templates have to be considered.

4 Problem Statement Reuse limitations of current model templates : Same process modeling language Same modeling tool Difficult to be queried beyond an enterprise Same terms are required when querying (keyword-based query)

5 Problem Statement The limitations are caused by semantic interoperability problems. Semantic interoperability problems: Model level Terms are used differently for the same concept in two models, e.g. ‘Client’ in model A and ‘Customer’ in model B; ‘purchase’ in model A and ‘buy’ in model B. Conceptualization mismatches, e.g. ’City’ is a class in model A and it is a attribute of another class in model B; ’finish’ is an action in model A but it is a state in model B.

6 Problem Statement Semantic interoperability problems: Meta model level Same concept but different terms are used in different modeling languages, e.g. ‘agent’ (ActionWorkflow)  ‘actor’ (Core Plan Representation) Same terms but the concepts are not totally same, e.g. ’activity’ is the atomic concept in PSL (Process Specific Language), but it is not an atomic concept in WooRKS

7 Assumption: process models in a same domain have common concepts process modeling languages have sufficient similarities of constructs Common understanding (process ontology) Model Meta-model Common understanding (domain ontology) Model Meta-model

8 Proposed Approach A common semantic annotation structure for process templates. Model profile annotation Model content annotation Meta-model annotation Figure1. Three model annotation aspects Model as a whole product Model fragments Modeling language

9 Proposed Approach Model Profile Annotation The basic description information about a process model template such as problem domain of the template, name of the template, author of the template, date of creation and etc. Refer to the description structure of patterns

10 Proposed Approach Model Content Annotation Contents of a process template: process and doamin parts Process part: workflow description Domain part: object-relation model (class model, ER model) Reference ontology Process reference ontology, process patterns, thesaurus Domain reference ontology, domain thesaurus

11 Proposed Approach Model Content Annotation Assumption: all process templates can be represented in XML/RDF. Markup annotation approach ’semAnn’:

12 Proposed Approach Meta-model Annotation Mapping process modeling languages into a semantics agreed process template modeling language. Annotate schema (XML Schema or RDF Schema)

13 Ontological Basis General Process Ontology (GPO) A set of concepts usually for describing semanitcs of a process Based on BWW-ontology and refer to other process ontologies and process modeling languages, such as TOVE, PIF-CORE, EEML, BPMN, BPML, PSL etc.

14 General process ontology (GPO)

15 Process Template Modeling Language (PTML) Process templates are models and a neutral process modeling language provides a unified way to represent process templates. Constructs of PTML try to cover most common and core constructs of various process modeling languages. PTML is derived from GPO. PTML is defined in RDFS or OWL.

16 Process Template Modeling Language (PTML)

17 Process Template Modeling Language (PTML) Note: PTML is not intended to be created as a completed executable process modeling language. Impossible to make exact one-one construct mapping between PTML and a specific process modeling language. A way of storing and representing the core model of process.

18 Semantic Annotation of Process Template Applications Annotate process templates and store them in repositories Retrieval desired process templates Reuse found process templates in new projects

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20 A Simple Example An EEML process template – a purchase process

21 A Simple Example An EEML process model template includes: Task: purchase Personrole: client (defined in the local domain model) The local process template is exported into a XML file, and linked to the local domain model in which roles and resources are defined. The EEML is defined in XMLS or DTD.

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23 A Simple Example

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25 Meta-model Annotation Meta model mapping EEML: task  PMTL: activity element EEML: personrole  PMTL: actor-role element Mapping Reasoning with general process ontology SKOS(Simple Knowledge Organization Systems) Other mapping tools

26 Meta-model Annotation SKOS is an RDF schema for representing thesauri and similar types of knowledge organization system (KOS). Construct task in EEML is replaced by ‘Activity_element’ in PTML. Process template is a RDF or OWL-based file.

27 Model Content Annotation – domain content annotation Local domain model is a local domain ontology Reference domain ontology or thesaurus is an agreed collection of concepts and their relations within a certain domain. Local concepts are annotated by common understanding concepts. Mapping of local doamin ontology and reference domain ontology

28 Model Content Annotation – domain content annotation

29 Model Content Annotation – process content annotation Annotate model fragments using GPO Apply the underlying relationship between GPO and PTML Annotate fragments with composed constructs (workflow patterns) Use ’semAnn’ annotation way

30 Annotatoin Result The abstracted template is represented by the process model template language. The IDs of model elements are reindexed. The semantics of the model elements are also annotated by the general process ontology. The terms can be replaced by synonym. The annotated domain model is linked to the template.

31 Template Query Application

32 Template Reuse Application Three operations on a template Domain specialization Process Refinment Required process modeling language transformation

33 Conclusions and Future Work Semantic interoperability issue of process models is vital in the following scenario: Process models exchange Process models integration Process knowledge sharing Process templates retrieval and reuse are applications normally used in above scenario. Related work Services-oriented: Bernstein et al., ’Towards High-Precision Service Retrieval’; Michael Kifer et al. ’A Logical Framework for Web Service Discovery’; Patil et al. ’METEOR-S Web Service Annotation Framework’ etc. Process Ontology: MIT process handbook, OWL-S, PSL, Aitken and Curtis’s ’Design of a Process Ontology: Vocabulary, Semantics and Usage’, UEML XML-based model exchange: XMI, Vanderhaeghen et al. ’XML-based Transformation of Business Process Models – Enabler for Collaboratiive Business Process Managemenrt’ and others Contributions: Two-level semantic interoperability of process templates: meta-model level and model level. Semantic annotation structure GPO and PTML

34 Conclusions and Future Work This is ongoing work. Some work is refined after this paper GPO is refined (GPO and PTML are combined); Semantic Annotation Model (Semantic Web Services technology is applied, such as OWL-S.) Goal-driven query Future work Continue to enrich semantics covered by GPO (refer to some process modeling languages comparison framework) Formulize semantics of GPO Refine semantic annotation model Semantic reasoning with annotation information (semantics mapping, WordNet, Racer) Prototype of semantic annotation and semantic retrieval of process templates