@inproceedings {INPROC-2012-16,
   author = {David Schumm and Dimitrios Dentsas and Michael Hahn and Dimka Karastoyanova and Frank Leymann and Mirko Sonntag},
   title = {{Web Service Composition Reuse through Shared Process Fragment Libraries}},
   booktitle = {Proceedings of the 12th International Conference on Web Engineering (ICWE 2012 Demos)},
   publisher = {Springer-Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   series = {Lecture Notes in Computer Science},
   pages = {1--4},
   type = {Workshop-Beitrag},
   month = {Juli},
   year = {2012},
   keywords = {Process Reuse; Service Composition; Web Services; BPEL; Process Fragments.},
   language = {Englisch},
   cr-category = {C.2.4 Distributed Systems,     D.2.2 Software Engineering Design Tools and Techniques,     H.3.5 Online Information Services,     H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {More and more application functionality is provided for use over corporate and public networks. Standardized technology stacks, like Web services, provide abstraction from the internal implementation. Coarse-grained units of Web service composition logic can be made reusable by capturing it as ‘process fragment’. Such fragments can be shared over the Web to simplify and accelerate development of process-based service compositions. In this demonstration, we present a framework consisting of an Eclipse-based process design environment that is integrated with a Web-based process fragment library. The framework enables extracting process fragments, publishing and sharing them on the Web, as well as search, retrieval, and their reuse in a given process. Process fragments can be shared with others using a Web frontend or through a plug-in within the process design environment which is building on Web service technology.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2012-16&engl=0}
}
@inproceedings {INPROC-2011-77,
   author = {Michael Reiter and Uwe Breitenb{\"u}cher and Schahram Dustdar and Dimka Karastoyanova and Frank Leymann and Hong-Linh Truong},
   title = {{A Novel Framework for Monitoring and Analyzing Quality of Data in Simulation Workflows}},
   booktitle = {2011 Seventh IEEE International Conference on eScience},
   publisher = {IEEE},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Konferenz-Beitrag},
   month = {Dezember},
   year = {2011},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation,     I.6.7 Simulation Support Systems},
   contact = {Michael Reiter Michael.Reiter@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {In recent years scientific workflows have been used for conducting data-intensive and long running simulations. Such simulation workflows have processed and produced different types of data whose quality has a strong influence on the final outcome of simulations. Therefore being able to monitor and analyze quality of this data during workflow execution is of paramount importance, as detection of quality problems will enable us to control the execution of simulations efficiently. Unfortunately, existing scientific workflow execution systems do not support the monitoring and analysis of quality of data for multi-scale or multi-domain simulations. In this paper, we examine how quality of data can be comprehensively measured within workflows and how the measured quality can be used to control and adapt running workflows. We present a quality of data measurement process and describe a quality of data monitoring and analysis framework that integrates this measurement process into a workflow management system.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2011-77&engl=0}
}
@inproceedings {INPROC-2011-62,
   author = {Michele Mancioppi and Olha Danylevych and Dimka Karastoyanova and Frank Leymann},
   title = {{Towards Classification Criteria for Process Fragmentation Techniques}},
   booktitle = {Proceedings of BPD 2011 (colocated with BPM 2011)},
   publisher = {Springer Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Workshop-Beitrag},
   month = {Dezember},
   year = {2011},
   keywords = {Process fragments, process fragmentation, process improvement techniques},
   language = {Englisch},
   cr-category = {D.2.2 Software Engineering Design Tools and Techniques,     H.4.1 Office Automation},
   contact = {michele.mancioppi@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Process fragmentation is the foundation of many state-of-the-art techniques for supporting management, reuse and change of process models. Such techniques vary greatly in terms of which types of processes they are applicable to, what they aim at accomplishing, how they define the resulting process fragments, etc. The comparison, analysis, reuse and selection of the available process fragmentation techniques are hindered by the lack of a common terminology and classification criteria, and by the large discrepancy in the characteristics that are covered when presenting novel fragmentation techniques. This work starts addressing this issue by investigating classification criteria for process fragmentation techniques based on the “seven Ws”, namely Why, What, When, Where, Who, Which, and hoW. The presented classification criteria are applied to some of the process fragmentation approaches available in the literature. In addition to enabling the classification of fragmentation techniques, the classification criteria here presented form a “check-list” for authors of future works in the field of process fragmentation.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2011-62&engl=0}
}
@inproceedings {INPROC-2011-56,
   author = {Mirko Sonntag and Dimka Karastoyanova},
   title = {{Enforcing the Repeated Execution of Logic in Workflows}},
   booktitle = {Proceedings of the 1st International Conference on Business Intelligence and Technology (BUSTECH 2011), Rome, Italy, 2011},
   publisher = {IARIA},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {1--6},
   type = {Konferenz-Beitrag},
   month = {September},
   year = {2011},
   keywords = {Service composition; Workflow adaptability; Iteration; Re-execution},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   contact = {Mirko Sonntag: sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The repeated execution of workflow logic is a feature needed in many situations. Repetition of activities can be modeled with workflow constructs (e.g., loops) or external workflow configurations, or can be triggered by a user action during workflow execution. While the first two options are state of the art in the workflow technology, the latter is currently insufficiently addressed in literature and practice. We argue that a manually triggered rerun operation enables both business users and scientists to react to unforeseen problems and thus improves workflow robustness, allows scientists steering the convergence of scientific results, and facilitates an explorative workflow development as required in scientific workflows. In this paper, we therefore formalize operations for the repeated enactment of activities—for both iteration and re-execution. Starting point of the rerun is an arbitrary, manually selected activity. Since we define the operations on a meta-model level, they can be implemented for different workflow languages and engines.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2011-56&engl=0}
}
@inproceedings {INPROC-2011-52,
   author = {Mirko Sonntag and Sven Hotta and Dimka Karastoyanova and David Molnar and Siegfried Schmauder},
   title = {{Using Services and Service Compositions to Enable the Distributed Execution of Legacy Simulation Applications}},
   booktitle = {Towards a Service-Based Internet, Proceedings of the 4th European Conference ServiceWave 2011, Poznan, Poland, 2011},
   editor = {W. Abramowicz and I.M. Llorente and M. Surridge and A. Zisman and J. Vayssi{\`e}re},
   publisher = {Springer-Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {1--12},
   type = {Konferenz-Beitrag},
   month = {Oktober},
   year = {2011},
   keywords = {Service compositions; Simulation workflows; distributed simulations; BPEL; Web services},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation,     I.6.7 Simulation Support Systems},
   contact = {Mirko Sonntag sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {In the field of natural and engineering science, computer simulations play an increasingly important role to explain or predict phenomena of the real world. Although the software landscape is crucial to support scientists in their every day work, we recognized during our work with scientific institutes that many simulation programs can be considered legacy monolithic applications. They are developed without adhering to known software engineering guidelines, lack an acceptable software ergonomics, run sequentially on single workstations and require tedious manual tasks. We are convinced that SOA concepts and the service composition technology can help to improve this situation. In this paper we report on the results of our work on the service- and service composition-based re-engineering of a legacy scientific application for the simulation of the ageing process in copper-alloyed. The underlying general concept for a distributed, service-based simulation infrastructure is also applicable to other scenarios. Core of the concept is a resource manager that steers server work load and handles simulation data.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2011-52&engl=0}
}
@inproceedings {INPROC-2011-50,
   author = {Mirko Sonntag and Dimka Karastoyanova},
   title = {{Compensation of Adapted Service Orchestration Logic in BPEL’n’Aspects}},
   booktitle = {Proceedings of the 9th International Conference on Business Process Management (BPM 2011), Clermont-Ferrand, France, 2011},
   publisher = {Springer-Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {1--16},
   type = {Konferenz-Beitrag},
   month = {August},
   year = {2011},
   keywords = {Workflow; Service Composition; BPEL; Compensation; Aspect-orientation; Adaptability},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   contact = {sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {BPEL’n’Aspects is a non-intrusive mechanism for adaptation of control flow of BPEL processes based on the AOP paradigm. It relies on Web service standards to weave process activities in terms of aspects into BPEL processes. This paper is a logical continuation of the BPEL’n’Aspects approach. Its main objective is to enable compensation of weaved-in Web service invocations (activities) in a straightforward manner. We present (1) requirements on a mechanism for compensation of weaved-in process activities; (2) the corresponding concepts and mechanisms to meet these requirements; (3) an example scenario to show the applicability of the approach; and (4) a prototypical implementation to prove the feasibility of the solution. This work represents an improvement in the applicability of this particular adaptation approach since processes in production need the means to compensate actions that are included into processes as result of an adaptation step, too. The concept is generic and hence can also be used by other approaches that adapt control flow.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2011-50&engl=0}
}
@inproceedings {INPROC-2011-48,
   author = {Mirko Sonntag and Katharina G{\"o}rlach and Dimka Karastoyanova and Frank Leymann and Polina Malets and David Schumm},
   title = {{Views on Scientific Workflows}},
   booktitle = {Proceedings of the 10th International Conference on Perspectives in Business Informatics Research (BIR 2011), 2011},
   publisher = {Springer-Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   series = {Lecture Notes in Business Information Processing},
   volume = {90},
   pages = {321--335},
   type = {Konferenz-Beitrag},
   month = {Oktober},
   year = {2011},
   keywords = {Process Views, BPEL, Web Services, SOA, Simulation Workflows, Scientific Workflows.},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   contact = {sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Workflows are becoming more and more important in e-Science due to the support they provide to scientists in computer simulations, experiments and calculations. Our experiences with workflows in this field and the literature show that scientific workflows consist of a large number of related information. This information is difficult to deal with in a single perspective and has changing importance to scientists in the different workflow lifecycle phases. In this paper we apply viewing techniques known from business process management to (service-based) scientific workflows to address these issues. We describe seven of the most relevant views and point out realization challenges. We argue that the selected views facilitate the handling of workflows to scientists and add further value to scientific workflow systems. An implementation of a subset of the views based on Web services and BPEL shows the feasibility of the approach. The presented work has the goal to increase additionally the acceptance of the workflow technology in e-Science.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2011-48&engl=0}
}
@inproceedings {INPROC-2011-35,
   author = {David Schumm and Jiayang Cai and Christoph Fehling and Dimka Karastoyanova and Frank Leymann and Monika Weidmann},
   title = {{Composite Process View Transformation}},
   booktitle = {Proceedings of the 12th International Conference on Electronic Commerce and Web Technologies},
   publisher = {Springer-Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   series = {Lecture Notes in Business Information Processing},
   volume = {85},
   pages = {52--63},
   type = {Konferenz-Beitrag},
   month = {August},
   year = {2011},
   isbn = {978-3-642-23013-4},
   keywords = {Process View, Service Composition, BPM},
   language = {Englisch},
   cr-category = {C.2.4 Distributed Systems,     D.2.2 Software Engineering Design Tools and Techniques,     H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The increasing complexity of processes used for design and execution of critical business activities demands novel techniques and technologies. Process viewing techniques have been proposed as a means to abstract from details, summarize and filter out information, and customize the visual appearance of a process to the need of particular stakeholders. However, composition of process view transformations and their provisioning as a service to enable their usage in various different scenarios is currently not discussed in research. In this paper, we present a lightweight, service-oriented approach to compose modular process viewing functions to form complex process view transformations which can be offered as a service. We introduce a concept and an architectural framework to generate process view service compositions automatically with focus on usability. Furthermore, we discuss key aspects regarding the implementation as well as different scenarios where process view services and their compositions are needed.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2011-35&engl=0}
}
@inproceedings {INPROC-2011-28,
   author = {Mirko Sonntag and Sven Hotta and Dimka Karastoyanova and David Molnar and Siegfried Schmauder},
   title = {{Workflow-Based Distributed Environment For Legacy Simulation Applications}},
   booktitle = {Proceedings of the 6th International Conference on Software and Data Technologies (ICSOFT 2011), Poster Paper},
   publisher = {SciTePress Digital Library},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {91--94},
   type = {Workshop-Beitrag},
   month = {Juli},
   year = {2011},
   doi = {10.5220/0003444400910094},
   keywords = {Simulation workflows; distributed simulations; BPEL; Web services; Monte-Carlo},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation,     I.6.7 Simulation Support Systems},
   contact = {Mirko.Sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Computer simulations play an increasingly important role to explain or predict phenomena of the real world. We recognized during our work with scientific institutes that many simulation programs can be considered legacy applications with low software ergonomics, usability, and hardware support. Often there is no GUI and tedious manual tasks have to be conducted. We are convinced that the information technology and software engineering concepts can help to improve this situation to a great extent. In this poster presentation we therefore propose a concept of a simulation environment for legacy scientific applications. Core of the concept are simulation workflows that enable a distributed execution of former monolithic programs and a resource manager that steers server work load and handles data. As proof of concept we implemented a Monte-Carlo simulation of precipitations in copper-alloyed iron and tested it with real data.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2011-28&engl=0}
}
@inproceedings {INPROC-2011-12,
   author = {Mirko Sonntag and Dimka Karastoyanova},
   title = {{Concurrent Workflow Evolution}},
   booktitle = {Electronic Communications of the EASST, Volume 37, ISSN 1863-2122},
   publisher = {Gesellschaft f{\"u}r Informatik e.V. (GI)},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {1--12},
   type = {Workshop-Beitrag},
   month = {M{\"a}rz},
   year = {2011},
   issn = {1863-2122},
   keywords = {Workflow evolution; scientific workflows; Model-as-you-go; BPEL},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   contact = {Mirko.Sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Workflow evolution is a collective term for concepts that deal with changes of workflow models. Adapted workflow models are deployed on a workflow engine as new model version. That means two versions of the same model are deployed on the engine. Typically, this results in conflicts between the workflow models. For example, how does a client find and choose the desired workflow version to instantiate? Typically, these problems are solved by deactivating the old model. New instances can only be created for the new model. In our work on scientific workflows we recognized that there are cases where it is desired to keep the old model activated. In this paper we investigate what it means to have several model versions active. We develop a general concept for this “concurrent workflow evolution” that solves emerging problems. Moreover, we show how this concept can be realized with BPEL.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2011-12&engl=0}
}
@inproceedings {INPROC-2011-07,
   author = {Peter Reimann and Michael Reiter and Holger Schwarz and Dimka Karastoyanova and Frank Leymann},
   title = {{SIMPL - A Framework for Accessing External Data in Simulation Workflows}},
   booktitle = {Datenbanksysteme f{\"u}r Business, Technologie und Web (BTW 2011), 14. Fachtagung des GI-Fachbereichs „Datenbanken und Informationssysteme“ (DBIS), Proceedings, 02.-04. M{\"a}rz 2011, Kaiserslautern, Germany},
   editor = {Gesellschaft f{\"u}r Informatik (GI)},
   publisher = {Lecture Notes in Informatics (LNI)},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   series = {Series of the Gesellschaft f{\"u}r Informatik (GI)},
   volume = {180},
   pages = {534--553},
   type = {Konferenz-Beitrag},
   month = {M{\"a}rz},
   year = {2011},
   isbn = {978-3-88579-274-1},
   keywords = {Data Provisioning; Workflow; Scientific Workflow; Simulation Workflow; BPEL; WS-BPEL; SIMPL},
   language = {Englisch},
   cr-category = {H.2.8 Database Applications,     H.4.1 Office Automation},
   contact = {Peter Reimann Peter.Reimann@ipvs.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Parallele und Verteilte Systeme, Anwendersoftware;     Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Adequate data management and data provisioning are among the most important topics to cope with the information explosion intrinsically associated with simulation applications. Today, data exchange with and between simulation applications is mainly accomplished in a file-style manner. These files show proprietary formats and have to be transformed according to the specific needs of simulation applications. Lots of effort has to be spent to find appropriate data sources and to specify and implement data transformations. In this paper, we present SIMPL – an extensible framework that provides a generic and consolidated abstraction for data management and data provisioning in simulation workflows. We introduce extensions to workflow languages and show how they are used to model the data provisioning for simulation workflows based on data management patterns. Furthermore, we show how the framework supports a uniform access to arbitrary external data in such workflows. This removes the burden from engineers and scientists to specify low-level details of data management for their simulation applications and thus boosts their productivity.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2011-07&engl=0}
}
@inproceedings {INPROC-2010-95,
   author = {Ralph Mietzner and Christoph Fehling and Dimka Karastoyanova and Frank Leymann},
   title = {{Combining Horizontal and Vertical Composition of Services}},
   booktitle = {Proceedings of IEEE International Conference on Service-Oriented Computing and Applications (SOCA 2010)},
   publisher = {IEEE},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Konferenz-Beitrag},
   month = {Dezember},
   year = {2010},
   keywords = {service composition; vertical composition; cloud; provisioning; virtual service},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   contact = {Ralph Mietzner},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Service composition is a well-established field of research in the service community. Services are commonly regarded as black boxes with well-defined interfaces that can be recursively aggregated into new services. The black-box nature of services does not only include the service implementation but also the middleware and hardware to run the services. Thus, service composition techniques are typically limited to choosing between a set of available services. In this paper we keep the black-box nature and the principle of information hiding for the service implementation, but break up services vertically. By introducing vertical service composition, we allow services to be provisioned on the right middleware when they are requested, thus making service-binding more powerful as services with the desired quality of service can be provisioned on demand. We introduce the concept of vertical service composition and present an extension to an enterprise service bus that implements the concept of vertical service composition by combining concepts from provisioning with those of (dynamic) service binding.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-95&engl=0}
}
@inproceedings {INPROC-2010-85,
   author = {Mirko Sonntag and Dimka Karastoyanova},
   title = {{BPEL’n’Aspects And Compensation: Adapted Service Orchestration Logic and its Compensation Using Aspects}},
   booktitle = {Proceedings of the 8th Int. Conf. on Service-Oriented Computing (ICSOC 2010), Demo Track, 2010},
   editor = {Mathias Weske and Jian Yang and Paul Maglio and Marcelo Fantinato},
   publisher = {Springer},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {1--2},
   type = {Workshop-Beitrag},
   month = {Dezember},
   year = {2010},
   keywords = {Service orchestration; BPEL; compensation; aspect-orientation; adaptability},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   contact = {sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {One of the main weaknesses of workflow management systems is their inflexibility regarding process changes. To address this drawback in our work on the BPEL’n’Aspects approach we developed a standards-based mechanism to adapt the control flow of BPEL processes [1]. It uses AOP techniques to non-intrusively weave Web service invocations in terms of aspects into BPEL processes. Aspects can be inserted before, instead or after BPEL elements and that way adaptation of running processes is enabled. In this work we want to present a novel extension of the BPEL’n’Aspects prototype that deals with the compensation of weaved-in aspects in a straight-forward manner. The extension enormously improves the applicability of the approach in real-world scenarios: processes in production need the means to compensate behavior that was inserted into the process in the course of adaptation steps. The ability to compensate weaved-in aspects distinguishes our approach from other existing concepts that introduce AOP techniques to business processes.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-85&engl=0}
}
@inproceedings {INPROC-2010-84,
   author = {Mirko Sonntag and Dimka Karastoyanova and Ewa Deelman},
   title = {{BPEL4Pegasus: Combining Business and Scientific Workflows}},
   booktitle = {Proceedings of the 8th Int. Conf. on Service-Oriented Computing (ICSOC 2010), Demo Track, 2010},
   editor = {Mathias Weske and Jian Yang and Paul Maglio and Marcelo Fantinato},
   publisher = {Springer},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {1--2},
   type = {Workshop-Beitrag},
   month = {Dezember},
   year = {2010},
   keywords = {Scientific workflows; business workflows; human tasks; Pegasus; BPEL},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   contact = {sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Business and scientific workflow management systems (WfMS) offer different features to their users because they are developed for different application areas with different requirements. Research is currently being done to extend business WfMSs by functionality that meets requirements of scientists and scientific applications. The idea is to bring the strengths of business WfMSs to e-Science. This means great effort in re-implementing features already offered by scientific WfMSs. In our work, we investigated another approach, namely combining business and scientific workflows and thus harnessing the advantages of both. We demonstrate a prototype that implements this idea with BPEL as business workflow language and Pegasus as scientific WfMS. Our motivation is the fact that the manual work to correctly install and configure Pegasus can be supervised by a BPEL workflow to minimize sources of failures and automate the overall process of scientific experimenting.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-84&engl=0}
}
@inproceedings {INPROC-2010-77,
   author = {Philipp Leitner and Branimir Wetzstein and Dimka Karastoyanova and Waldemar Hummer and Schahram Dustdar and Frank Leymann},
   title = {{Preventing SLA Violations in Service Compositions Using Aspect-Based Fragment Substitution}},
   booktitle = {Proceedings of the 8th International Conference on Service Oriented Computing (ICSOC 2010)},
   publisher = {Springer Berlin Heidelberg},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Konferenz-Beitrag},
   month = {Dezember},
   year = {2010},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {In this paper we show how the application of the aspect-oriented programming paradigm to runtime adaptation of service compositions can be used to prevent SLA violations. Adaptations are triggered by predicted violations, and are implemented as substitutions of fragments in the service composition. Fragments are full-fledged standalone compositions, and are linked into the original composition via special activities, which we refer to as virtual activities. Before substitution we evaluate fragments with respect to their expected impact on the performance of the composition, and choose those fragments which are best suited to prevent a predicted violation. We show how our approach can be implemented using Windows Workflow Foundation technology, and discuss our work based on an illustrative case study.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-77&engl=0}
}
@inproceedings {INPROC-2010-52,
   author = {David Schumm and Dimka Karastoyanova and Frank Leymann and Steve Strauch},
   title = {{Fragmento: Advanced Process Fragment Library}},
   booktitle = {Proceedings of the 19th International Conference on Information Systems Development (ISD'10), Prague, Czech Republic, August 25 - 27, 2010},
   publisher = {Springer},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {659--670},
   type = {Konferenz-Beitrag},
   month = {August},
   year = {2010},
   isbn = {978-1-4419-9645-9},
   keywords = {Process Fragment; Process Design; Reusability; Process Library},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation,     D.3.3 Programming Language Constructs and Features},
   contact = {David.Schumm@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Reuse is a common discipline for decreasing software development time and for improving overall quality, independent from the domain. As business processes represent a fundamental asset of an organization, several concepts for enabling reuse during process modeling have been proposed. However, only few concrete examples for reusable process artifacts have been discussed so far. In this paper, we present the concept of process fragments and an example collection of process fragments for illustrating our reuse concept and for showing that it can ac-tually be applied in practice for an easier and faster development of process-based applications. The fragment examples demonstrate different characteristics such fragments may exhibit. We also argue that this work will encourage reuse of process logic in terms of fragments since it also provides an opportunity to design and develop a process fragment library for collecting process logic explicitly. As technical enabler for the approach we present a prototype called Fragmento.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-52&engl=0}
}
@inproceedings {INPROC-2010-26,
   author = {Mirko Sonntag and Natalia Currle-Linde and Katharina G{\"o}rlach and Dimka Karastoyanova},
   title = {{Towards Simulation Workflows With BPEL: Deriving Missing Features From GriCoL}},
   booktitle = {Proceedings of the 21st IASTED International Conference on Modelling and Simulation (MS 2010), 2010.},
   editor = {R.S. Alhajj and V.C.M. Leung and M. Saif and R. Thring},
   publisher = {ACTA Press},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Konferenz-Beitrag},
   month = {Juli},
   year = {2010},
   keywords = {Simulation tools and languages; Workflow management; BPEL; GriCoL},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation,     H.3.4 Information Storage and Retrieval Systems and Software},
   contact = {mirko.sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {In this paper, we investigate the suitability of the generalpurpose workflow language BPEL to create executable simulation workflows. We therefore compare BPEL to GriCoL, a graphical language with proven applicability for simulation workflows in Grid environments. We discover a number of incomparable concepts in the two languages. On the one hand, BPEL’s unique features in comparison to GriCoL reveal the rationale behind the approach of using BPEL as basis for a simulation workflow language. On the other hand, based on the features of GriCoL, we are able to discuss how to extend BPEL in order to increase its expressiveness for simulation workflows.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-26&engl=0}
}
@inproceedings {INPROC-2010-23,
   author = {Mirko Sonntag and Dimka Karastoyanova},
   title = {{Next Generation Interactive Scientific Experimenting Based On The Workflow Technology}},
   booktitle = {Proceedings of the 21st IASTED International Conference on Modelling and Simulation (MS 2010), 2010.},
   editor = {R.S. Alhajj and V.C.M. Leung and M. Saif and R. Thring},
   publisher = {ACTA Press},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Konferenz-Beitrag},
   month = {Juli},
   year = {2010},
   keywords = {Simulation tools and languages; Workflow management; Workflow adaptation; SOA},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation,     H.3.4 Information Storage and Retrieval Systems and Software},
   contact = {mirko.sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {In this paper we explore to what extent the conventional workflow technology and service-oriented architecture (SOA) principles can be applied to support scientist in their experiments. Based on the requirements imposed on systems for scientific computing, e-Science and simulations, and an extended workflow life cycle we introduce the architecture of an interactive system that reuses the conventional workflow technology. We advocate the realization of this workflow system with advanced adaptation and monitoring features because we identified that modeling of scientific applications and simulations can only be done the “scientists’ way” if the traditional workflow modeling as well as design and run time adaptation are combined in a user-friendly solution.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-23&engl=0}
}
@inproceedings {INPROC-2010-115,
   author = {Mirko Sonntag and Dimka Karastoyanova and Ewa Deelman},
   title = {{Bridging The Gap Between Business And Scientific Workflows}},
   booktitle = {Proceedings of the IEEE 6th International Conference on e-Science, Brisbane, Australia, December 7-10, 2010},
   publisher = {IEEE Computer Society},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {206--213},
   type = {Konferenz-Beitrag},
   month = {Dezember},
   year = {2010},
   doi = {10.1109/eScience.2010.12},
   keywords = {Scientific workflows; Business workflows; Human tasks; Pegasus; BPEL},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   contact = {sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Due to their different target applications business and scientific workflow systems provide different sets of features to their users. Significant amount of research is currently being done to employ the business workflow technology in the scientific domain. This usually means extending the workflow language and thus the modeling tool and execution engine. In this paper we aim to bring business and scientific workflows together in order to exploit the advantages of both. We explore the interplay between business and scientific workflows in the context of human interactions with the management of workflow execution. We present an approach and implementation based on BPEL and Pegasus and show that the approach can be beneficial to scientists.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-115&engl=0}
}
@inproceedings {INPROC-2010-10,
   author = {Andreas Gehlert and Olha Danylevych and Dimka Karastoyanova},
   title = {{From Requirements to Executable Processes - A Literature Study.}},
   booktitle = {In Proceedings of the 5th International Workshop on Business Process Design (BPD 2009), Ulm, Germany, 7 September 2009},
   publisher = {BPD'09},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {1--11},
   type = {Workshop-Beitrag},
   month = {Januar},
   year = {2010},
   keywords = {Requirement Engineering, Business Process Modelling, Process Merge},
   language = {Englisch},
   cr-category = {D.2.2 Software Engineering Design Tools and Techniques,     D.2.13 Software Engineering Reusable Software,     H.4.1 Office Automation},
   contact = {olha.danylevych@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Service compositions are a major component to realize service-based applications (SBAs). The design of these service compositions follows mainly a process-modelling approach - an initial business process is refined until it can be executed on a workflow engine. Although this process-modelling approach proved to be useful, it largely disregards the knowledge gained in the requirements engineering discipline, e. g. in eliciting, documenting, managing and tracing requirements. Disregarding the requirements engineering phase may lead to undesired effects of the later service compositions such as lack of acceptance by the later users. To defuse this potentially critical issue we are interested in the interplay between requirements engineering and process modelling techniques. As a first step in this direction, we analyse the current literature in requirements engineering and process modelling in order to find overlaps where the techniques from both domains can be combined in useful ways. Our main finding is that scenario-based approaches from the requirements engineering discipline are a good basis for deriving executable processes. Depending whether the focus is on requirements engineering or on process design the inte-gration of the techniques are slightly different.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-10&engl=0}
}
@inproceedings {INPROC-2010-09,
   author = {Mirko Sonntag and Dimka Karastoyanova and Frank Leymann},
   title = {{The Missing Features of Workflow Systems for Scientific Computations}},
   booktitle = {Proceedings of the 3rd Grid Workflow Workshop (GWW), Software Engineering Conference, GI-Edition Lecture Notes in Informatics (LNI), P-160},
   publisher = {Gesellschaft f{\"u}r Informatik e.V. (GI)},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {209--216},
   type = {Workshop-Beitrag},
   month = {Februar},
   year = {2010},
   isbn = {978-3-88579-254-3},
   keywords = {Business Workflow Management, Scientific Workflow Management},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   contact = {Mirko.Sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {This paper discusses technical aspects of how business workflow management systems can be improved in order to apply them in the field of scientific workflows and reap all their benefits. We give recommendations how to address the discovered gaps in support for scientific applications. The approach we follow addresses the requirements of scientists and scientific applications, which we also identify in this work.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-09&engl=0}
}
@inproceedings {INPROC-2010-01,
   author = {Branimir Wetzstein and Dimka Karastoyanova and Oliver Kopp and Frank Leymann and Daniel Zwink},
   title = {{Cross-Organizational Process Monitoring based on Service Choreographies}},
   booktitle = {Proceedings of the 25th Annual ACM Symposium on Applied Computing (SAC 2010); Sierre, Switzerland, 21-26 March, 2010},
   publisher = {ACM},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {2485--2490},
   type = {Konferenz-Beitrag},
   month = {M{\"a}rz},
   year = {2010},
   doi = {10.1145/1774088.1774601},
   keywords = {Business Activity Monitoring, Cross-Organizational Monitoring, Service Choreography},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   contact = {branimir.wetzstein@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Business process monitoring in the area of service oriented computing is typically performed using business activity monitoring technology in an intra-organizational setting. Due to outsourcing and the increasing need for companies to work together to meet their joint customer demands, there is a need for monitoring of business processes across organizational boundaries. Thereby, partners in a choreography have to exchange monitoring data, in order to enable process tracking and evaluation of process metrics. In this paper, we describe an event-based monitoring approach based on BPEL4Chor service choreography descriptions. We show how to define monitoring agreements specifying events each partner in the choreography has to provide. We distinguish between resource events and complex events for calculation of process metrics using complex event processing technology. We present our implementation and evaluate the concepts based on a scenario.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2010-01&engl=0}
}
@inproceedings {INPROC-2009-82,
   author = {Raman Kazhamiakin and Branimir Wetzstein and Dimka Karastoyanova and Marco Pistore and Frank Leymann},
   title = {{Adaptation of Service-Based Applications Based on Process Quality Factor Analysis}},
   booktitle = {Proceedings of the 2nd Workshop on Monitoring, Adaptation and Beyond (MONA+), co-located with ICSOC/ServiceWave 2009},
   publisher = {Online},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Workshop-Beitrag},
   month = {November},
   year = {2009},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {When service-based applications implement business processes, it is important to monitor their performance in terms of Key Performance Indicators (KPIs). If monitoring results show that the KPIs do not reach target values, the influential factors have to be analyzed and corresponding adaptation actions have to be taken. In this paper we present a novel adaptation approach for service-based applications (SBAs) based on a process quality factor analysis. This approach uses decision trees for showing the dependencies of KPIs on process quality factors from different functional levels of an SBA. We extend the monitoring and analysis approach and show how the analysis results may be used to come up with an adaptation strategy leading to an SBA that satisfies KPI values. The approach includes creation of a model which associates adaptation actions to process quality metrics, extraction of adaptation requirements based on analysis results, and identification of an adaptation strategy which can consist of several adaptation actions on different functional levels of an SBA.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-82&engl=0}
}
@inproceedings {INPROC-2009-76,
   author = {Tobias Anstett and Dimka Karastoyanova and Frank Leymann and Ralph Mietzner and Ganna Monakova and Daniel Schleicher and Steve Strauch},
   title = {{MC-Cube: Mastering Customizable Compliance in the Cloud}},
   booktitle = {Proceedings of the 7th International Joint Conference on Service Oriented Computing, Stockholm, Sweden, November 23-27, 2009},
   editor = {Springer},
   publisher = {Springer Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {592--606},
   type = {Konferenz-Beitrag},
   month = {November},
   year = {2009},
   keywords = {Cloud Computing; IaaS; PaaS; SaaS; Monitoring; Enforcement},
   language = {Englisch},
   cr-category = {H.2.7 Database Administration},
   contact = {anstett@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Outsourcing parts of a company's processes becomes more and more important in a globalized, distributed economy. While archi- tectural styles and technologies such as service-oriented architecture and Web services facilitate the distribution of business process over several departments, enterprises and countries, these business processes still need to comply with various regulations. These regulations can be company regulations, national, or international regulations. When outsourcing IT-functions, enterprises must ensure that the overall regulations are met. Therefore they need evidence from their outsourcing partners that supports the proof of compliance to regulations. Furthermore it must be possible to enforce the adherence to compliance rules at partners. In this paper we introduce so-called compliance interfaces that can be used by customers to subscribe to evidence at a provider and to enforce regulations at a provider. We introduce a general compliance architecture that allows compliance to be monitored and enforced at services deployed in any emerging cloud delivery model.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-76&engl=0}
}
@inproceedings {INPROC-2009-54,
   author = {Dimka Karastoyanova and Frank Leymann},
   title = {{BPEL’n’Aspects: Adapting Service Orchestration Logic}},
   booktitle = {Proceedings of 7th International Conference on Web Services (ICWS 2009)},
   address = {Los Angeles, CA, USA},
   publisher = {IEEE},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Konferenz-Beitrag},
   month = {Juli},
   year = {2009},
   doi = {10.1109/ICWS.2009.75},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   contact = {dimka.karastoyanova@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The need for flexibility in process-based applications, in particular during their execution, places the demand for enabling adaptability of processes. AOP is considered to be one of the approaches to flexibly switch on and off functionality on per-instance basis in applications during their execution; analogously, this paradigm can be applied in a BPEL environment to enable adaptation of running orchestrations. In the presented approach we strive towards reuse of as much concepts and technology already available in a Web service (WS) environment as possible. We combine standard BPEL, the publish/subscribe paradigm and WS-Policy so that WS operations play the role of aspects with respect to BPEL processes. We present the syntax for such aspects as an extension of the WS-Policy framework. We introduce the architecture of the supporting infrastructure and a prototypical implementation. The approach draws on the combined benefits of service orientation and the AOP paradigm to improve the state-of-the-art techniques for flexibility of service orchestrations in a non-intrusive manner.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-54&engl=0}
}
@inproceedings {INPROC-2009-40,
   author = {Ralph Mietzner and Tammo van Lessen and Alexander Wiese and Matthias Wieland and Dimka Karastoyanova and Frank Leymann},
   title = {{Virtualizing Services and Resources with ProBus: The WS-Policy-Aware Service and Resource Bus}},
   booktitle = {Proceedings of the 7th International Conference on Web Services (ICWS) 2009},
   publisher = {IEEE Computer Society},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Konferenz-Beitrag},
   month = {Juli},
   year = {2009},
   keywords = {WS-Policy; WSRF; Enterprise Service Bus; ESB; Service Selection},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {A fundamental principle of service oriented architectures is the decoupling of service requesters and service providers to enable late binding of services at deployment time or even dynamic binding of services at runtime. This is important in enterprise settings, where different services that implement business functions in critical business processes are dynamically chosen based on availability or price. The same problem also applies to dynamic Grid environments where resources need to be dynamically chosen based on availability and other non-functional properties. The WS-Policy framework describes how policies for both providers and requesters are specified to allow the selection of services based on these policies. Existing approaches, using WS-Policy, have drawbacks by placing the burden of the service selection partially on the client. In this paper we present an approach to extend an enterprise service bus that allows service clients to submit policies the service provider needs to comply with directly in the message that triggers the service invocation. We show how these policies are evaluated in the bus and how policies are defined for not only stateless services, but also stateful resources.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-40&engl=0}
}
@inproceedings {INPROC-2009-27,
   author = {David Schumm and Dimka Karastoyanova and Frank Leymann and J{\"o}rg Nitzsche},
   title = {{On Visualizing and Modelling BPEL with BPMN}},
   booktitle = {IEEE Proceedings of the 4th International Workshop on Workflow Management (IWWM2009)},
   editor = {Henning M{\"u}ller and Jinjun Chen and Massimo Cafaro and Jong Hyuk Park and Nabil Abdennadher},
   address = {Los Alamitos, California},
   publisher = {IEEE Computer Society},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {80--87},
   type = {Workshop-Beitrag},
   month = {Mai},
   year = {2009},
   isbn = {978-0-7695-3677-4},
   keywords = {BPEL; BPMN; Modelling; Visualizing},
   language = {Englisch},
   cr-category = {D.2.2 Software Engineering Design Tools and Techniques,     H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The advantages of the process-based approach to implementing applications lead to the development of notations for modelling business processes and languages for enacting them in a process engine for the purpose of process automation. Currently the Business Process Modeling Notation (BPMN) is typically used for modelling business processes and the Business Process Execution Language (BPEL) is used as the process execution format. Both languages differ in purpose, expressivity and operational semantics. Recently it has been shown that there is no complete bi-directional mapping between BPMN and BPEL and transformations have been defined between the two formalisms. However, these transformations lead to more complex models in both, BPEL and BPMN, and enable a roundtrip for only a limited number of scenarios. In this paper we show how BPEL processes can be modelled using the graphical aspect of BPMN in order to facilitate modelling of executable processes using BPMN while avoiding model transformations.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-27&engl=0}
}
@inproceedings {INPROC-2009-25,
   author = {Tammo van Lessen and J{\"o}rg Nitzsche and Dimka Karastoyanova},
   title = {{Facilitating Rich Data Manipulation in BPEL using E4X}},
   booktitle = {Proceedings of the 1st Central-European Workshop on Services and their Composition, ZEUS 2009, Stuttgart, Germany, March 2--3, 2009},
   editor = {Oliver Kopp and Niels Lohmann},
   address = {Stuttgart},
   publisher = {CEUR-WS.org},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   series = {CEUR Workshop Proceedings},
   volume = {438},
   pages = {102--108},
   type = {Workshop-Beitrag},
   month = {M{\"a}rz},
   year = {2009},
   issn = {1613-0073},
   keywords = {WS-BPEL; BPEL; JavaScript; E4X; ECMAScript; XML},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/INPROC-2009-25/INPROC-2009-25.pdf},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The Business Process Execution Language (BPEL) uses XML to specify the data used within a process and realizes data flow via (globally) shared variables. Additionally, assign activities can be used to copy (parts of) variables to other variables using techniques like XPath or XSLT. Although BPEL’s built-in functionality is sufficient for simple data manipulation tasks, it becomes very cumbersome when dealing with more sophisticated data models, such as arrays. ECMAScript for XML (E4X) extends JavaScript with support for XML-based data manipulation by introducing new XPath-like language features. In this paper we show how E4X can help to significantly ease data manipulation tasks and propose a BPEL extension that allows employing JavaScript/E4X for implementing them. As E4X allows defining custom functions in terms of scripts, reusability with respect to data manipulation is improved. To verify the conceptual framework we present a proof-of-concept implementation based on Apache ODE.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-25&engl=0}
}
@inproceedings {INPROC-2009-19,
   author = {Olha Danylevych and Dimka Karastoyanova and Frank Leymann},
   title = {{Optimal Stratification of Transactions}},
   booktitle = {ICIW 2009},
   publisher = {IEEE Computer Society},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Konferenz-Beitrag},
   month = {Mai},
   year = {2009},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   ee = {www.iaria.org/conferences2009/ICIW09.html},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The performance of a system (implementing business processes) is directly influenced by the way its operations are split into transactions. Stratified transactions a produced by the stratification approach presented in this paper and is a way to manage a global transaction by combining the transactions coordinated using the tho-phase commit protocol (2PC) and queued transactions. In the presented stratification approach the sub-transactions are partitioned into the so-called strata which employ 2PC for transaction coordination, and the strata communicate via persistent queues. This paper investigates the mechanisms for building an optimally stratified transaction regarding certain evaluation criteria. We investigate the applicability of algorithms for local search like the hillclimbing and simulated annealing for transaction stratification, and introduce a hybrid method combining both approaches to tackle its disadvantage. We also used the population-based optimization approach (evolutionary programming). We produce recommendations for use of all the approaches depending on the optimization criteria. The approach can be applied for fragmenting workflow-based service compositions in an optimal manner and thus support the out-sourcing and insourcing scenarios.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-19&engl=0}
}
@inproceedings {INPROC-2009-14,
   author = {Andreas Gehlert and Julia Hielscher and Olha Danylevych and Dimka Karastoyanova},
   title = {{Online Testing, Requirements Engineering and Service Faults as Drivers for Adapting Service Compositions}},
   booktitle = {ServiceWave 2008, MONA+},
   publisher = {Springer Berlin Heidelberg},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Workshop-Beitrag},
   month = {Februar},
   year = {2009},
   keywords = {Service Composition, Adaptability, Requirements Engineering, Online Testing, Self-optimization, Web Services},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   ee = {http://www.s-cube-network.eu/MONA},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Adaptability is a key feature of service-based applications (SBAs). Multiple approaches for adaptability, including those borrowed from the tradi-tional workflow technology, can be used to react to various types of changes in the SBA’s environment. Unlike previous fragmented research, we aim at pre-senting a unified view reflecting the convergence of approaches from require-ments engineering, online testing and adaptation mechanisms for service com-positions. The main result of our approach is that a dynamic binding strategy known from service composition research leads to an interaction of the re-quirements engineering and online testing activities with an enterprise service registry only and, therefore, to a loose coupling between the three activities.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-14&engl=0}
}
@inproceedings {INPROC-2009-02,
   author = {Thorsten Scheibler and Dimka Karastoyanova and Frank Leymann},
   title = {{Dynamic Message Routing Using Processes}},
   booktitle = {Proceedings of 16th Fachtagung Kommunikation in Verteilten Systemen (KiVS 09)},
   publisher = {Springer},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Konferenz-Beitrag},
   month = {M{\"a}rz},
   year = {2009},
   keywords = {SOAP, Routing, BPEL, ESB, SOA},
   language = {Englisch},
   cr-category = {D.2.2 Software Engineering Design Tools and Techniques,     D.2.11 Software Engineering Software Architectures,     D.2.13 Software Engineering Reusable Software},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The Enterprise Service Bus (ESB) is composable middleware that provides applications with services such as message routing and transformation, service compositions, dynamic discovery, transactional support, coordination, security features, and others. In an ESB supporting SOAP message exchange routing algorithms typically follow the sequential SOAP message processing model, where SOAP headers are the main artefacts used to specify the message route and the processing of the payload by intermediaries along that route. This model supports neither alternative nor parallel message routes. In the case of a failing intermediary node this leads to a failure in the message delivery. Moreover, the execution order of services on SOAP message payloads at the intermediaries cannot be prescribed. In this paper, we demonstrate how the deficiencies of the SOAP message processing model can be addressed. We introduce an approach that allows for specifying SOAP message routing logic in terms of BPEL processes. We show that parallel and alternative routes for SOAP messages can be modelled and executed, and the order of services that process a message at intermediaries can be predefined to accommodate the correct processing sequence, as required by the concrete application domain. Features like dynamic discovery of services and flexible service composition are leveraged to enable flexible SOAP message routing.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2009-02&engl=0}
}
@inproceedings {INPROC-2008-72,
   author = {Oliver Kopp and Branimir Wetzstein and Ralph Mietzner and Stefan Pottinger and Dimka Karastoyanova and Frank Leymann},
   title = {{A Model-Driven Approach to Implementing Coordination Protocols in BPEL}},
   booktitle = {1st International Workshop on Model-Driven Engineering for Business Process Management (MDE4BPM 2008)},
   publisher = {Springer-Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   series = {Lecture Notes in Business Information Processing},
   volume = {17},
   pages = {188--199},
   type = {Workshop-Beitrag},
   month = {September},
   year = {2008},
   doi = {10.1007/978-3-642-00328-8_19},
   keywords = {MDA; BPEL; WS-Coordination; WS-Business Activity},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation,     K.4.4 Electronic Commerce},
   ee = {http://www.inf.unisi.ch/mde4bpm08/},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {WS-Coordination defines a framework for establishing pro- tocols for coordinating the outcome agreement within distributed ap- plications. The framework is extensible and allows support for multiple coordination protocols. To facilitate the realization of new coordination protocols we present a model-driven approach for the generation of BPEL processes used as implementation of coordination protocols. We show how coordination protocols can be modeled in domain-specific graph-based diagrams and how to transform such graphs into abstract BPEL process models representing the behavior of the coordinator and the participants in the protocol.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2008-72&engl=0}
}
@inproceedings {INPROC-2008-47,
   author = {Carlos Pedrinaci and Christian Brelage and Tammo van Lessen and John Domingue and Dimka Karastoyanova and Frank Leymann},
   title = {{Semantic Business Process Management: Scaling up the Management of Business Processes}},
   booktitle = {Proceedings of the 2nd IEEE International Conference on Semantic Computing (ICSC) 2008},
   publisher = {IEEE Computer Society},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {546--553},
   type = {Konferenz-Beitrag},
   month = {August},
   year = {2008},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Business Process Management (BPM) aims at supporting the whole life-cycle necessary to deploy and maintain business processes in organisations. Despite its success however, BPM suffers from a lack of automation that would support a smooth transition between the business world and the IT world. We argue that Semantic BPM, that is, the enhancement of BPM with Semantic Web Services technologies, provides further scalability to BPM by increasing the level of automation that can be achieved. We describe the particular SBPM approach developed within the SUPER project and we illustrate how it contributes to enhancing existing BPM solutions in order to achieve more flexible, dynamic and manageable business processes.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2008-47&engl=0}
}
@inproceedings {INPROC-2008-121,
   author = {Branimir Wetzstein and Dimka Karastoyanova and Frank Leymann},
   title = {{Towards Management of SLA-Aware Business Processes Based on Key Performance Indicators}},
   booktitle = {Proceedings of the 9th Workshop on Business Process Modeling, Development, and Support (BPMDS'08); Montpellier, France, June 16 – 17, 2008},
   publisher = {Online},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Workshop-Beitrag},
   month = {Juni},
   year = {2008},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {It is increasingly important that Service Level Agreements (SLAs) are taken into account when business processes are exposed as services in a Service Oriented Architecture. SLAs define expected service behavior and non-functional properties of the service. The fact that the service provider has to offer certain guarantees concerning SLA properties has an impact on the business process lifecycle. In this paper we introduce a stepwise approach for management of SLA-aware service compositions based on process performance requirements specified as Key Performance Indicators. The approach is based on the process lifecycle known from Business Process Management and comprises a modeling, configuration and execution phase. We incorporate existing work on SLA modeling, QoS aggregation, and QoS-based service selection, and identify several problems specific to SLA-aware business processes.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2008-121&engl=0}
}
@inproceedings {INPROC-2008-09,
   author = {Dimka Karastoyanova and Tammo van Lessen and Frank Leymann and Zhilei Ma and J{\"o}rg Nitzsche and Branimir Wetzstein and Sami Bhiri and Manfred Hauswirth and Maciej Zaremba},
   title = {{A Reference Architecture for Semantic Business Process Management Systems}},
   booktitle = {Multikonferenz Wirtschaftsinformatik 2008},
   editor = {Martin Bichler and Thomas Hess and Helmut Krcmar and Ulrike Lechner and Florian Matthes and Arnold Picot and Benjamin Speitkamp and Petra Wolf},
   address = {Berlin},
   publisher = {GITO-Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {371--372},
   type = {Konferenz-Beitrag},
   month = {Februar},
   year = {2008},
   isbn = {978-3-940019-34-9},
   language = {Englisch},
   cr-category = {H.5.4 Hypertext/Hypermedia},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Semantic Business Process Management (SBPM) enhances BPM with semantic technologies in order to increase the degree of automation in the BPM lifecycle and help in bridging the gap between the business and IT views on business processes. In this paper, we describe the architecture of an SBPM System (SBPMS) which supports the whole SBPM lifecycle by providing functionality for process modeling, process configuration, process execution, and process analysis. We analyze the functional requirements of the SBPMS from the business user's and the IT expert's point of view and derive and describe the components of the SBPMS and their key interactions to achieve the required functionalities. We show how existing BPMS components can be extended to use semantics, and describe the integration of new components, such as a Semantic Execution Environment. The presented SBPMS is based on BPMN, BPEL and WSMO technologies.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2008-09&engl=0}
}
@inproceedings {INPROC-2007-99,
   author = {Rania Khalaf and Dimka Karastoyanova and Frank Leymann},
   title = {{Pluggable Framework for Enabling the Execution of Extended BPEL Behavior}},
   booktitle = {Proceedings of the 3rd International Workshop on Engineering Service-Oriented Application (WESOA'2007)},
   publisher = {Unbekannt},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Workshop-Beitrag},
   month = {September},
   year = {2007},
   doi = {10.1007/978-3-540-93851-4_37},
   keywords = {Web services, AOP, middleware reuse, business process, BPEL},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Adding runtime support for BPEL extensions typically requires (1) reacting to navigation events from a BPEL engine executing an extended process model and (2) affecting the engine’s navigation behavior based on external triggers. This is usually achieved in a proprietary way for each engine and for each extension. In this paper, we provide a systematic approach to controlling and reacting to process behavior as well as growing the set of supported control points, thus enabling support for multiple application domains in a composable manner in a BPEL engine. The framework presented in this paper (1) enables a BPEL engine to support extensions, even on existing BPEL processes, and (2) allows developers to create pluggable extension implementations that can be reused across multiple BPEL engines. An implementation of the approach is presented and used in three different projects that need widely differing extended BPEL capabilities.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-99&engl=0}
}
@inproceedings {INPROC-2007-63,
   author = {J{\"o}rg Nitzsche and Tammo van Lessen and Dimka Karastoyanova and Frank Leymann},
   title = {{BPEL for Semantic Web Services (BPEL4SWS)}},
   booktitle = {Proceedings of the 3rd International Workshop on Agents and Web Services in Distributed Environments AWeSome'07 -- On the Move to Meaningful Internet Systems 2007: OTM 2007 Workshops},
   publisher = {Springer-Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   series = {Lecture Notes in Computer Science},
   volume = {4805/2007},
   pages = {179--188},
   type = {Workshop-Beitrag},
   month = {November},
   year = {2007},
   isbn = {978-3-540-76887-6},
   doi = {10.1007/978-3-540-76888-3_37},
   keywords = {WS-BPEL; BPELlight; BPEL4SWS; Semantic Web Services; SWS; BPM},
   language = {Englisch},
   cr-category = {C.2.4 Distributed Systems,     D.2.11 Software Engineering Software Architectures,     D.2.12 Software Engineering Interoperability,     H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {In this paper we present BPEL for Semantic Web Services (BPEL4SWS) - a language that facilitates the orchestration of Semantic Web Services using a process based approach. It is based on the idea of WSDL-less BPEL and enables describing activity implementations semantically which increases the flexibility of business processes. Following an approach that uses a set of composable standards and specifications, BPEL4SWS is independent of any Semantic Web Service framework. It can be used to compose Semantic Web Services, traditional Web Services and a mix of them.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-63&engl=0}
}
@inproceedings {INPROC-2007-60,
   author = {Tammo van Lessen and Branimir Wetzstein and J{\"o}rg Nitzsche and Zhilei Ma and Dimka Karastoyanova and Frank Leymann},
   title = {{Gesch{\"a}ftsprozessmanagement Meets Semantic Web.}},
   booktitle = {Tagungsband Science Meets Business. Stuttgarter Softwaretechnik Forum 2007, Fraunhofer IAO, 23. November 2007.},
   editor = {D. Spath and A. Weisbecker and O. H{\"o}{\ss} and J. (Hrsg.) Drawehn},
   address = {Stuttgart},
   publisher = {Fraunhofer IRB Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {75--83},
   type = {Konferenz-Beitrag},
   month = {November},
   year = {2007},
   isbn = {3-8167-7493-8},
   keywords = {Semantic Business Process Management},
   language = {Deutsch},
   cr-category = {H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {23. November 2007 Science Meets Business Am vierten Tag des Stuttgarter Softwaretechnik Forums geben Experten aus Forschung und Wissenschaft Einblick in aktuelle Forschungsarbeiten in den Themenbereichen Softwareengineering, Softwaretechnik und Mobile Anwendungen. Dadurch k{\"o}nnen die Zuh{\"o}rer interessante Impulse f{\"u}r ihr t{\"a}gliches Business sowie einen Ausblick auf zuk{\"u}nftige Trends und Entwicklungen mitnehmen.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-60&engl=0}
}
@inproceedings {INPROC-2007-24,
   author = {J{\"o}rg Nitzsche and Tammo van Lessen and Dimka Karastoyanova and Frank Leymann},
   title = {{BPEL light}},
   booktitle = {Proceedings of the 5th International Conference on Business Process Management (BPM 2007)},
   publisher = {Springer-Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   series = {Lecture Notes in Computer Science},
   volume = {4714},
   pages = {214--229},
   type = {Konferenz-Beitrag},
   month = {September},
   year = {2007},
   doi = {10.1007/978-3-540-75183-0_16},
   keywords = {BPEL; BPEL light; WSDL-less BPEL; BPM; Workflow; SOA; Web services; flexibility; reusability},
   language = {Englisch},
   cr-category = {C.2.4 Distributed Systems,     D.2.11 Software Engineering Software Architectures,     D.2.12 Software Engineering Interoperability,     H.4.1 Office Automation},
   contact = {joerg.nitsche@iaas.uni-stuttgart.de and tammo.van.lessen@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {In this paper we present BPEL light which decouples process logic from interface definitions. By extending BPEL 2.0 with a WSDL-less interaction model, BPEL light allows to specify process models independent of Web service technology. Since its interaction model is based on plain message exchange, it is completely independent of any interface description language. This fosters flexibility and reusability of process models and enables modelling platform and component model independent business processes. The presented approach takes a significant step towards narrowing down the gap between business level and IT level by facilitating a more business-oriented modelling of executable processes.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-24&engl=0}
}
@inproceedings {INPROC-2007-22,
   author = {Dimka Karastoyanova and Branimir Wetzstein and Tammo van Lessen and Daniel Wutke and J{\"o}rg Nitzsche and Frank Leymann},
   title = {{Semantic Service Bus: Architecture and Implementation of a Next Generation Middleware}},
   booktitle = {Proceedings of the Second International ICDE Workshop on Service Engineering (SEIW 2007)},
   publisher = {IEEE Computer Society},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {347--354},
   type = {Workshop-Beitrag},
   month = {April},
   year = {2007},
   isbn = {1-4244-0832-6},
   doi = {10.1109/ICDEW.2007.4401015},
   keywords = {Semantic Service Bus; SSB; Enterprise Service Bus; BPEL},
   language = {Englisch},
   cr-category = {C.2.4 Distributed Systems,     D.2.11 Software Engineering Software Architectures,     D.2.12 Software Engineering Interoperability,     H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {In this paper we present a middleware for the Service Oriented Architecture, called the Semantic Service Bus. It is an advanced middleware possessing enhanced features, as compared to the conventional service buses. It is distinguished by the fact that it uses semantic description of service capabilities, as well as requirements towards services to enable more elaborate service discovery, selection, routing, composition and data mediation. The contributions of the paper are the conceptual architecture of the Semantic Service Bus and a prototypical implementation supporting different semantic Web service technologies (OWL and WSMO) and vanilla Web services. Since the mission critical application scenarios (for SOA) involve complex orchestrations of services, we have chosen to utilize semantically annotated service orchestrations as the applications to use this middleware.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-22&engl=0}
}
@inproceedings {INPROC-2007-100,
   author = {Tammo van Lessen and J{\"o}rg Nitzsche and Marin Dimitrov and Mihail Konstantinov and Dimka Karastoyanova and Luchesar Cekov and Frank Leymann},
   title = {{An Execution Engine for Semantic Business Processes}},
   booktitle = {Proceedings of Service-Oriented Computing - ICSOC 2007 Workshops},
   publisher = {Springer-Verlag},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   series = {Lecture Notes in Computer Science},
   volume = {4907},
   pages = {200--211},
   type = {Workshop-Beitrag},
   month = {September},
   year = {2007},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation,     K.1 The Computer Industry},
   ee = {www.sysedv.tu-berlin.de/semsoc/},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {In this paper we present the architecture and design of an extended BPEL engine that implements the operational semantics of BPEL4SWS. BPEL4SWS is an extension of the BPEL language with support for Semantic Web Service concepts like mediation and semantic descriptions of activity implementations. We describe the basic communication scenarios of processes with services and the interaction between the engine components involved in the execution of BPEL4SWS processes. The presented prototype is based on the open source BPEL engine Apache ODE, features improved configurability and facilitates the definition of additional BPEL extensions with minimal development effort.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2007-100&engl=0}
}
@inproceedings {INPROC-2006-86,
   author = {Dimka Karastoyanova and Frank Leymann and J{\"o}rg Nitsche and Branimir Wetzstein and Daniel Wutke},
   title = {{Utilizing Semantic Web Service Technologies for Automatic Execution of Parameterized BPEL Processes}},
   booktitle = {XML Tage 2006},
   publisher = {Unbekannt},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   type = {Konferenz-Beitrag},
   month = {September},
   year = {2006},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation,     K.1 The Computer Industry},
   ee = {http://www.xml-clearinghouse.de/ws/XMLT2006/2/},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Utilizing Semantic Web Service Technologies for Automatic Execution of Parameterized BPEL Processes},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2006-86&engl=0}
}
@inproceedings {INPROC-2006-82,
   author = {Dimka Karastoyanova and Frank Leymann and J{\"o}rg Nitzsche and Branimir Wetzstein and Daniel Wutke},
   title = {{Parameterized BPEL Processes: Concepts and Implementation}},
   booktitle = {Business Process Management},
   editor = {Schahram Dustdar and Jos{\'e} Luiz Fiadeiro and Amit P. Sheth},
   publisher = {Springer},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   series = {Lecture Notes in Computer Science},
   volume = {4102},
   pages = {471--476},
   type = {Konferenz-Beitrag},
   month = {September},
   year = {2006},
   isbn = {3-540-38901-6},
   doi = {10.1007/11841760_41},
   language = {Englisch},
   cr-category = {K.1 The Computer Industry},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {This paper presents the concept of parameterized WS-flows and two extensions to the BPEL language for enabling it. Another major contribution is a prototypical infrastructure enacting the execution, monitoring and adaptation of parameterized BPEL processes. The advantages of parameterized BPEL processes are the improved flexibility and reusability.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2006-82&engl=0}
}
@inproceedings {INPROC-2005-122,
   author = {Dimka Karastoyanova and Frank Leymann and Alejandro P. Buchmann},
   title = {{An Approach to Parameterizing Web Service Flows}},
   booktitle = {Proc. 3rd Intl. Conf. on Service Oriented Computing (ICSOC’2005)},
   editor = {Boualem Benatallah and Fabio Casati and Paolo Traverso},
   address = {Amsterdam, The Netherlands},
   publisher = {Springer},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   series = {Lecture Notes in Computer Science},
   volume = {3826},
   pages = {533--538},
   type = {Konferenz-Beitrag},
   month = {November},
   year = {2005},
   isbn = {3-540-30817-2},
   doi = {10.1007/11596141_45},
   language = {Englisch},
   cr-category = {K.1 The Computer Industry},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The flexibility and reusability of Web Service flows (WS-flows) are limited especially by the fact that portType and operation names are hard-coded in the process definition. In this paper we argue that through parameterization and substitution WS-flows flexibility can be improved, while reusability is enhanced. We introduce a meta-model extension to enable run time evaluation of parameter values and thus discard the need to predict any possible partner service types during process modeling. The extension enables also run time changes in portType values. We show how the approach can be mapped to BPEL. We discuss prototypical implementation for the extended functionality and present conclusions and ideas for future work.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2005-122&engl=0}
}
@inproceedings {INPROC-2005-121,
   author = {Dimka Karastoyanova and Alejandro Houspanossian and Mariano Cilia and Frank Leymann and Alejandro P. Buchmann},
   title = {{Extending BPEL for Run Time Adaptability}},
   booktitle = {Ninth IEEE International Enterprise Computing Conference (EDOC 2005)},
   publisher = {IEEE Computer Society},
   institution = {Universit{\"a}t Stuttgart, Fakult{\"a}t Informatik, Elektrotechnik und Informationstechnik, Germany},
   pages = {15--26},
   type = {Konferenz-Beitrag},
   month = {September},
   year = {2005},
   isbn = {0-7695-2441-9},
   doi = {10.1109/EDOC.2005.14},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The existing Web service flow (WS-flow) technologies enable both static and dynamic binding of participating Web services (WSs) on the process model level. Adaptability on per-instance basis is not sufficiently supported and therefore must be addressed to improve process flexibility upon changes in the environment. Ad-hoc process instance changes can be enabled by swapping participating WS instances, by modifying port types of the partners to be invoked, and by changing process logic. In this work, we address the problem of dynamic binding of WSs to WS-flow instances at run time, i.e. the ability to exchange a WS instance participating in a WS-flow instance with an alternative one. The problem is additionally complicated by the fact that the execution of a process depends on its deployment. We describe the ``find and bind'' mechanism, and we show its representation as a BPEL extension. We discuss the benefits that could be gained and the disadvantages it brings in. The mechanism extends and improves the existing process technologies. It facilitates a precisely controlled policy-based selection of WSs at run time and also provides for process instance repair, while maintaining simplicity. We also discuss a prototypical implementation of the presented functionality.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INPROC-2005-121&engl=0}
}
@article {ART-2012-08,
   author = {Branimir Wetzstein and Asli Zengin and Raman Kazhamiakin and Annapaola Marconi and Marco Pistore and Dimka Karastoyanova and Frank Leymann},
   title = {{Preventing KPI Violations in Business Processes based on Decision Tree Learning and Proactive Runtime Adaptation}},
   journal = {Journal of Systems Integration},
   publisher = {Online},
   volume = {3},
   number = {1},
   pages = {3--18},
   type = {Artikel in Zeitschrift},
   month = {Januar},
   year = {2012},
   issn = {1804-2724},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The performance of business processes is measured and monitored in terms of Key Performance Indicators (KPIs). If the monitoring results show that the KPI targets are violated, the underlying reasons have to be identified and the process should be adapted accordingly to address the violations. In this paper we propose an integrated monitoring, prediction and adaptation approach for preventing KPI violations of business process instances. KPIs are monitored continuously while the process is executed. Additionally, based on KPI measurements of historical process instances we use decision tree learning to construct classification models which are then used to predict the KPI value of an instance while it is still running. If a KPI violation is predicted, we identify adaptation requirements and adaptation strategies in order to prevent the violation.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2012-08&engl=0}
}
@article {ART-2012-01,
   author = {Ralph Retter and Christoph Fehling and Dimka Karastoyanova and Frank Leymann and Daniel Schleicher},
   title = {{Combining Horizontal and Vertical Composition of Services}},
   journal = {Service Oriented Computing and Applications},
   publisher = {Springer},
   pages = {1--11},
   type = {Artikel in Zeitschrift},
   month = {Januar},
   year = {2012},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation,     C.2.4 Distributed Systems,     D.2.2 Software Engineering Design Tools and Techniques,     D.2.3 Software Engineering Coding Tools and Techniques},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Service composition is a well-established field of research in the service community. Services are commonly regarded as black boxes with well-defined interfaces that can be recursively aggregated into new services. The black-box nature of services does not only include the service implementation but also implies the use of middleware and hardware to run the services. Thus, service composition techniques are typically limited to choosing between a set of available services. In this paper we keep the black-box nature and the principle of information hiding of services, but in addition we break up services vertically. By introducing vertical service composition, we allow services to be provisioned on-demand using the middleware and runtime environment that specifically meets user-required quality of services (QoS). Therefore, a service is setup individually for services requestors instead of providing them with a pre-determined list of available services to choose from. We introduce the concept of vertical service composition and present an extension to an enterprise service bus (ESB) that implements the concept of vertical service composition by combining concepts from provisioning with those of (dynamic) service binding.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2012-01&engl=0}
}
@article {ART-2011-18,
   author = {Oliver Kopp and Katharina G{\"o}rlach and Dimka Karastoyanova and Frank Leymann and Michael Reiter and David Schumm and Mirko Sonntag and Steve Strauch and Tobias Unger and Matthias Wieland and Rania Khalaf},
   title = {{A Classification of BPEL Extensions}},
   journal = {Journal of Systems Integration},
   publisher = {Online},
   volume = {2},
   number = {4},
   pages = {2--28},
   type = {Artikel in Zeitschrift},
   month = {November},
   year = {2011},
   issn = {1804-2724},
   keywords = {BPEL Extension; Classification of Extensions; Extension Guidelines},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   ee = {ftp://ftp.informatik.uni-stuttgart.de/pub/library/ncstrl.ustuttgart_fi/ART-2011-18/ART-2011-18.pdf,     http://www.si-journal.org/index.php/JSI/article/view/103},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The Business Process Execution Language (BPEL) has emerged as de-facto standard for business processes implementation. This language is designed to be extensible for including additional valuable features in a standardized manner. There are a number of BPEL extensions available. They are, however, neither classified nor evaluated with respect to their compliance to the BPEL standard. This article fills this gap by providing a framework for classifying BPEL extensions, a classification of existing extensions, and a guideline for designing BPEL extensions.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2011-18&engl=0}
}
@article {ART-2011-02,
   author = {David Schumm and Dimka Karastoyanova and Oliver Kopp and Frank Leymann and Mirko Sonntag and Steve Strauch},
   title = {{Process Fragment Libraries for Easier and Faster Development of Process-based Applications}},
   journal = {Journal of Systems Integration},
   publisher = {Online},
   volume = {2},
   number = {1},
   pages = {39--55},
   type = {Artikel in Zeitschrift},
   month = {Januar},
   year = {2011},
   issn = {1804-2724},
   keywords = {Process Fragment; Process Design; Reusability; Process Library.},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   ee = {http://www.si-journal.org/,     http://www.si-journal.org/index.php/JSI/article/view/83},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The term “process fragment” is recently gaining momentum in business process management research. We understand a process fragment as a connected and reusable process structure, which has relaxed completeness and consistency criteria compared to executable processes. We claim that process fragments allow for an easier and faster development of process-based applications. As evidence to this claim we present a process fragment concept and show a sample collection of concrete, real-world process fragments. We present advanced application scenarios for using such fragments in development of process-based applications. Process fragments are typically managed in a repository, forming a process fragment library. On top of a process fragment library from previous work, we discuss the potential impact of using process fragment libraries in cross-enterprise collaboration and application integration.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2011-02&engl=0}
}
@article {ART-2010-14,
   author = {Dimka Karastoyanova and Tammo van Lessen and Ralph Mietzner},
   title = {{BPM au{\ss}erhalb der Verwaltung: Ein Blick {\"u}ber den Tellerrand}},
   journal = {Business Technology 3.2010 - Prozesse},
   publisher = {Software \& Support Verlag},
   pages = {54--58},
   type = {Artikel in Zeitschrift},
   month = {Oktober},
   year = {2010},
   keywords = {BPM; Systems Management; Nexus; SimTech; Software Engineering; Message Exchange Patterns},
   language = {Deutsch},
   cr-category = {H.4.1 Office Automation},
   ee = {http://it-republik.de/business-technology/bt-magazin-ausgaben/Prozesse-000420.html},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Beim Thema Gesch{\"a}ftsprozessmanagement (Business Process Management (BPM)) denken wir unweigerlich an Dokumentation und Werkzeugunterst{\"u}tzung f{\"u}r administrative Prozesse wie Kreditgenehmigungs-, Reisebuchungs- und Versicherungsantragsprozesse. Doch auch in anderen Dom{\"a}nen wie der Produktion, dem Systems Management, der Softwareentwicklung, der Forschung oder der Simulation etc. kommen Methoden und Techniken des Gesch{\"a}ftsprozessmanagements zunehmend zum Einsatz. In diesem Artikel stellen wir Anwendungsf{\"a}lle und BPM-L{\"o}sungen f{\"u}r diese Dom{\"a}nen vor und beleuchten die Vorteile, die aus einem durchg{\"a}ngigen BPM-Ansatz entstehen.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2010-14&engl=0}
}
@article {ART-2010-10,
   author = {Olha Danylevych and Dimka Karastoyanova and Frank Leymann},
   title = {{Service Networks Modelling: An SOA \& BPM Standpoint}},
   journal = {Journal of Universal Computer Science (J.UCS)},
   publisher = {JUCS},
   volume = {16},
   number = {13},
   pages = {1668--1693},
   type = {Artikel in Zeitschrift},
   month = {September},
   year = {2010},
   keywords = {service networks; service oriented architecture; software services; business process management; business processes; BPMN},
   language = {Englisch},
   cr-category = {D.2.9 Software Engineering Management,     H.1 Models and Principles,     H.3.5 Online Information Services},
   ee = {http://www.jucs.org/jucs_16_13/service_networks_modelling_an},
   contact = {olha.danylevych@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Services are quintessential in the current economical landscape. Enterprises and businesses at large rely on the consumption and providing of services to ensure their operations and to realize their business offers. That is, nowadays businesses all over the world are interconnected with each other by complex service-centric webs called service networks. The ubiquity and pervasiveness of service networks call for models, methods, mechanisms and tools to understand them and harness their potential. This paper investigates the modelling of the service networks with a focus on business relationships and exchanges of software services among the involved parties. The contribution of this work is threefold. Firstly, we provide an overview of what service networks modelling can offer in combination with Business Process Management (BPM) and Service Oriented Architecture (SOA) technologies. Secondly, we propose a formalism to model service networks that depicts them as aggregations of participants – e.g. enterprises or individuals – that offer, request, consume and provide services to each other. With the goal of providing a foundation for the alignment between service network- and business process models, we finally map the constructs of our service networks modelling formalism to the ones of the Business Process Modelling Notation (BPMN).},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2010-10&engl=0}
}
@article {ART-2010-02,
   author = {Mirko Sonntag and Katharina G{\"o}rlach and Dimka Karastoyanova and Frank Leymann and Michael Reiter},
   title = {{Process Space-based Scientific Workflow Enactment}},
   journal = {International Journal of Business Process Integration and Management (IJBPIM) Special Issue on Scientific Workflows, Vol 5, No. 1, pp. 32-44},
   publisher = {Inderscience Publishers},
   pages = {32--44},
   type = {Artikel in Zeitschrift},
   month = {April},
   year = {2010},
   keywords = {BPEL; Process Space; Scientific Workflow; Data References; Distributed System},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation,     H.3.4 Information Storage and Retrieval Systems and Software},
   contact = {Mirko.Sonntag@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {In the scientific field, the workflow technology is often employed to conduct computer simulations or computer supported experiments. The underlying IT infrastructure typically comprises resources distributed among different institutes and organizations all over the world. Traditionally, workflows are executed on a single machine while the invoked software is accessed remotely. This approach imposes many drawbacks which are outlined in this paper. To address these weaknesses we investigate the application of decentralized workflow enactment in the scientific domain. In this context, we explore the employment of process spaces, a middleware for the decentralized execution of workflows. Furthermore, we propose the combination of process spaces with the concept of data references to increase the overall performance of distributed simulations based on workflows. The considerations are discussed with the help of a scenario that calculates and visualizes the ink diffusion in water over a period of time.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2010-02&engl=0}
}
@article {ART-2009-02,
   author = {Ralph Mietzner and Dimka Karastoyanova and Frank Leymann},
   title = {{Business Grid: Combining Web Services and the Grid}},
   journal = {Transactions on Petri Nets and Other Models of Concurrency (ToPNoC) Special Issue on Concurrency in Process-aware Information Systems.},
   publisher = {Springer Verlag},
   type = {Artikel in Zeitschrift},
   month = {Januar},
   year = {2009},
   language = {Englisch},
   cr-category = {H.3.4 Information Storage and Retrieval Systems and Software},
   contact = {mietzner@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The common overarching goal of service bus and Grid middleware is ``virtualization'' – virtualization of business functions and virtualization of resources, respectively. By combining both capabilities a new infrastructure called ``Business Grid'' results. This infrastructure meets the requirements of both business applications and scientific computations in a unified manner and in particular those that are not addressed by the middleware infrastructures in each of the fields. Furthermore, it is the basis for enacting new trends like Software as a Service or Cloud computing. In this paper the overall architecture of the Business Grid is outlined. The Business Grid applications are described and the need for their customizability and adaptability is advocated. Requirements on the Business Grid like concurrency, multi-tenancy and scalability are addressed. The concept of ``provisioning flows'' and other mechanisms to enable scalability as required by a high number of concurrent users are outlined.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2009-02&engl=0}
}
@article {ART-2008-20,
   author = {J{\"o}rg Nitzsche and Tammo van Lessen and Dimka Karastoyanova and Frank Leymann},
   title = {{Composing Services on the Grid Using BPEL4SWS}},
   journal = {Multiagent and Grid Systems},
   publisher = {IOS Press},
   volume = {4},
   type = {Artikel in Zeitschrift},
   month = {Dezember},
   year = {2008},
   keywords = {Grid; BPEL; BPEL4SWS; Grid Services; Web Services; Semantic Web Services; Scientific Workflows},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Service composition on the Grid is a challenging task as documented in existing research work. Even though there are initial attempts to use the Business Process Execution Language (BPEL) to compose services on the Grid, still there is a significant lack of flexibility and reusability needed in scientific applications. In this paper we present BPEL for Semantic Web Services (BPEL4SWS) - a language that facilitates the orchestration of Grid Services exposed as traditional Web Services or Semantic Web Services using a process-based approach. It is based on the idea of WSDL-less BPEL and incorporates semantic descriptions of process activity implementations which increases the flexibility of business workflows as well as scientific workflows. Following an approach that uses a set of composable standards and specifications, BPEL4SWS is independent of any Semantic Web Service framework and therefore can also utilize any kind of Semantic Grid services. The advantages of BPEL4SWS are: (1) compliance with standards, (2) independence on service technologies, (3) applicability for both business applications as well as scientific workflows that use Grid services, (4) improved flexibility of processes.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2008-20&engl=0}
}
@article {ART-2007-07,
   author = {J{\"o}rg Nitzsche and Tammo van Lessen and Dimka Karastoyanova and Frank Leymann},
   title = {{WSMO/X in the context of business processes: improvement recommendations}},
   journal = {International Journal of Web Information Systems},
   publisher = {Emerald},
   volume = {3},
   number = {1/2},
   pages = {89--103},
   type = {Artikel in Zeitschrift},
   month = {Januar},
   year = {2007},
   issn = {1744-0084},
   doi = {10.1108/17440080710829234},
   keywords = {WSMO; WSMX; BPEL; BPM; SWS; Semantic Web Services},
   language = {Englisch},
   cr-category = {C.2.4 Distributed Systems,     D.2.11 Software Engineering Software Architectures,     D.2.12 Software Engineering Interoperability,     H.4.1 Office Automation},
   ee = {http://www.emeraldinsight.com/Insight/viewContentItem.do?contentType=Article&contentId=1630706},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Service-oriented architecture (SOA) is an architecture paradigm targeting integration of applications within and across enterprise boundaries. It has gathered research and industry acceptance and has given an enormous impetus to the business process management technology. Web service (WS) technology is one implementation of the SOA paradigm. It enables seamless integration of new and legacy applications through a stack of standardized composable specifications. WS orchestration is facilitated by the Business Process Execution Language which provides a recursive service composition model. While the programming model the WS technology provides is very flexible, a major deficiency is the need to discover services implementing a particular abstract interface, whereas functional similarities of services are disregarded. The Semantic Web Service technologies, like Web Service Modelling Ontology (WSMO) and Web Ontology Language for Services have been developed with the purpose of eliminating these deficiencies by enabling service discovery based on functional and non-functional properties. The paper aims to focus on these issues. This paper presents a list of requirements that business processes impose on SOA applications. It analyzes the support that WSMO/Web Service Model eXecution environment (WSMX) provides to address these requirements and compares it with the support enabled by the WS specification stack. The paper identifies major flaws in the WSMO model and its reference implementation with respect to business process support. The paper recommends possible solutions for eliminating the lack of needed features on behalf of WSMO/WSMX. It presents in detail how to enable asynchronous stateful communication among WSMO WS and partner-based WS discovery by extending the WSMO model. Additionally, it extends the API of the reference implementation to facilitate the execution of services communicating asynchronously.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=ART-2007-07&engl=0}
}
@inbook {INBOOK-2011-01,
   author = {Katharina G{\"o}rlach and Mirko Sonntag and Dimka Karastoyanova and Frank Leymann and Michael Reiter},
   title = {{Conventional Workflow Technology for Scientific Simulation}},
   series = {Guide to e-Science},
   publisher = {Springer-Verlag},
   pages = {323--352},
   type = {Beitrag in Buch},
   month = {M{\"a}rz},
   year = {2011},
   isbn = {978-0-85729-438-8},
   keywords = {Business workflows; BPEL; Scientific workflows; Simulation; Workflow Management Systems},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   ee = {http://www.springer.com/computer/information+systems+and+applications/book/978-0-85729-438-8},
   contact = {Katharina G{\"o}rlach: goerlach@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Workflow technology is established in the business domain for several years. This fact suggests the need for detailed investigations in the qualification of conven-tional workflow technology for the evolving application domain of e-Science. This chapter discusses the requirements on scientific workflows, the state of the art of scientific workflow management systems as well as the ability of conven-tional workflow technology to fulfill requirements of scientists and scientific ap-plications. It becomes clear that the features of conventional workflows can be advantageous for scientists but also that thorough enhancements are needed. We therefore propose a conceptual architecture for scientific workflow management systems based on the business workflow technology as well as extensions of exist-ing workflow concepts in order to improve the ability of established workflow technology to an application in the scientific domain with focus on scientific simulations.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2011-01&engl=0}
}
@inbook {INBOOK-2010-06,
   author = {Dimka Karastoyanova},
   title = {{On Scientific Experiments and Flexible Service Compositions}},
   series = {From Active Data Management to Event-Based Systems and More. Festschrift.},
   address = {Berlin Heidelberg New York},
   publisher = {Springer Verlag},
   series = {LNCS},
   volume = {6462},
   pages = {175--194},
   type = {Beitrag in Buch},
   month = {November},
   year = {2010},
   isbn = {978-3-642-17225-0},
   keywords = {scientific workflows, service composition, flexibility, BPEL, Web Services},
   language = {Englisch},
   cr-category = {C.2 Computer-Communication Networks,     H.4 Information Systems Applications,     D.2 Software Engineering,     H.3 Information Storage and Retrieval,     I.2 Artificial Intelligence,     C.2.4 Distributed Systems},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The IT support for scientific experimenting and e-science is currently not at the level of maturity of the support enterprises obtain. Since recently there is a trend of reusing existing enterprise software and related concepts for scientific experiments, scientific workflows and simulation. Most notably these are the workflow technology, which is widely used in business process management (BPM), and integration paradigms like the service oriented architecture (SOA). In this work we give an overview of open issues in the support for scientific experiments and possible approaches to addressing them in a service-based environment. We identify the need for enhancing the BPM practices, technologies and techniques in order to render them applicable in the area of scientific experimenting. We stress on the even greater importance of workflow flexibility and also show why flexibility techniques are crucial when it is about improving the IT support for scientists.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2010-06&engl=0}
}
@inbook {INBOOK-2010-04,
   author = {George Baryannis and Olha Danylevych and Dimka Karastoyanova and Kritikos Kyriakos and Philipp Leitner and Florian Rosenberg and Branimir Wetzstein},
   title = {{Service Composition}},
   series = {Service Research Challenges and Solutions for the Future Internet: S-Cube - Towards Engineering, Managing and Adapting Service-Based Systems},
   publisher = {Springer},
   series = {Lecture Notes in Computer Science},
   volume = {6500},
   pages = {55--84},
   type = {Beitrag in Buch},
   month = {Oktober},
   year = {2010},
   isbn = {978-3-642-17598-5},
   language = {Englisch},
   cr-category = {C.2 Computer-Communication Networks,     F.3 Logics and Meanings of Programs,     D.2 Software Engineering,     I.2 Artificial Intelligence,     H.4 Information Systems Applications,     H.3 Information Storage and Retrieval},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {The Internet has reached a crossroads in its evolution from a source of information to a critical infrastructure, underpinning economies and everyday life. The demand for more multimedia content, interconnected devices, greater connectivity, richer user experiences and services available at any time and from anywhere is increasing the pressure on existing networks and platforms. In this ubiquitous Internet, the number and scope of services available globally are predicted to grow exponentially leading to the ‘Internet of Services’. However, in order for these services to be used and re-used in the construction and evolution of service-based systems, significant research effort is required into the broader aspects of services and particularly into the multidisciplinary problems that cut across diverse scientific disciplines. The S-Cube Network of Excellence is one of more than 50 projects within the European Union's FP7 - ICT Programme for Research and Development researching various aspects of the Internet of Services. Within this cohort, S-Cube focuses on fundamental principles, techniques and methods for the service-based systems of the future, combining knowledge from experts in the areas of grid computing, service-oriented computing, business process management, software engineering and human-computer interaction. This book presents the foundations, vision, first results and future work in the area of software services as addressed by S-Cube. The book starts with a presentation of the S-Cube research framework, developed to assist in unifying research communities and agendas across Europe, and provides an introduction to the vision of S-Cube, where the anticipated growth in services and service-based systems will have a profound effect on business and society. The remainder of the book follows the building blocks of the research framework and addresses technologies required for realizing future service-based systems and service engineering principles, techniques and methods that use those technologies to ensure robust, manageable and adaptable systems.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2010-04&engl=0}
}
@inbook {INBOOK-2010-03,
   author = {Dimka Karastoyanova and Frank Leymann},
   title = {{Making Scientific Applications on the Grid Reliable through Flexibility Approaches Borrowed from Service Compositions}},
   series = {Handbook of Research on P2P and Grid Systems for Service-Oriented Computing: Models, Methodologies and Applications. Volume II.},
   publisher = {IGI Global},
   pages = {635--656},
   type = {Beitrag in Buch},
   month = {Januar},
   year = {2010},
   doi = {10.4018/978-1-61520-686-5},
   language = {Englisch},
   cr-category = {H.0 Information Systems General,     H.1.0 Information Systems Models and Principles General,     H.m Information Systems Miscellaneous,     J.1 Administration Data Processing,     J.2 Physical Sciences and Engineering},
   ee = {http://www.igi-global.com/bookstore/TitleDetails.aspx?TitleId=37249&DetailsType=AffiliateBio},
   contact = {Dimka Karastoyanova dimka.karastoyanova@iaas.uni-stuttgart.de},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Making Scientific Applications on the Grid Reliable through Flexibility Approaches Borrowed from Service Compositions Dimka Karastoyanova, Frank Leymann IAAS, University of Stuttgart, Germany e-mail: {Karastoyanova, Leymann}@iaas.uni-stuttgart.de Abstract The current trend in Service Oriented Computing (SOC) is to enable support for new delivery models of software and applications. These endeavours impose requirements on the resources and services used, on the way applications are created and on the QoS characteristics of the applications and the supporting infrastructure. Scientific applications on the other hand require improved robustness and reliability of the supporting Grid infrastructures where resources appear and disappear constantly. Enabling business model like Software as a Service (SaaS), Infrastructure as a Service (IaaS), and guaranteeing reliability of Grid infrastructures are requirements that both business and scientific application nowadays impose. The convergence of existing approaches from SOC and Grid Computing is therefore an obvious need. In this work we give an overview of the state-of-the-art of the overlapping research done in the area of SOC and Grid computing with respect to meeting the requirements of the applications in these two areas. We show that the requirements of business applications that already exploit service-oriented architectures (SOA) and the scientific application utilizing Grid infrastructures overlap. Due to the limited extent of cooperation between the two research communities the research results are either overlapping or diverging in spite of the similarities in requirements. Notably, some of the techniques developed in each area are needed but still missing in the other area and vice versa. We argue therefore that in order to enable an enterprise-strength service-oriented infrastructure one needs to combine and leverage the existing Grid and Service middleware in terms of architectures and implementations. We call such an infrastructure the Business Grid. Based on the Business Grid vision we focus in this work on presenting how reliability and robustness of the Business Grid can be improved by employing approaches for flexibility of service compositions. An overview and assessment of these approaches are presented together with recommendations for use. Based on the assumption that Grid services are Web services, these approaches can be utilized to improve the reliability of the scientific applications thus drawing on the advantages flexible workflows provide. This way we improve the robustness of scientific applications by making them flexible and hence improve the features of business applications that employ Grid resources and Grid service compositions to realize the SaaS, IaaS etc. delivery models.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2010-03&engl=0}
}
@inbook {INBOOK-2010-02,
   author = {Frank Leymann and Dimka Karastoyanova and Mike Papazoglou},
   title = {{Business Process Management Standards}},
   series = {Handbook on Business Process Management 1},
   publisher = {Springer-Verlag},
   type = {Beitrag in Buch},
   month = {Juli},
   year = {2010},
   isbn = {978-3-642-00415-5},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   ee = {http://www.springer.com/business+%26+management/business+information+systems /book/978-3-642-00415-5,     http://www.bpm-handbook.com/},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Business Process Management Standards},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2010-02&engl=0}
}
@inbook {INBOOK-2009-02,
   author = {Dimka Karastoyanova and Tammo van Lessen and Frank Leymann and Zhilei Ma and J{\"o}rg Nitzsche and Branimir Wetzstein},
   title = {{Semantic Business Process Management: Applying Ontologies in BPM}},
   series = {Handbook of Research on Business Process Modeling},
   publisher = {Information Science Publishing},
   pages = {312--330},
   type = {Beitrag in Buch},
   month = {April},
   year = {2009},
   isbn = {978-1-60566-288-6},
   keywords = {SBPM; BPEL4SWS; SOA; BPM; SWS},
   language = {Englisch},
   cr-category = {H.4.1 Office Automation},
   ee = {http://www.igi-global.com/reference/details.asp?ID=33287},
   department = {Universit{\"a}t Stuttgart, Institut f{\"u}r Architektur von Anwendungssystemen},
   abstract = {Even though process orientation/BPM is a widely accepted paradigm with heavy impact on industry and research the available technology does not support the business professionals’ tasks in an appropriate manner that is in a way allowing processes modeling using concepts from the business domain. This results in a gap between the business people expertise and the IT knowledge required. The current trend in bridging this gap is to utilize technologies developed for the Semantic Web, for example ontologies, while maintaining reusability and flexibility of processes. In this chapter the authors present an overview of existing technologies, supporting the BPM lifecycle, and focus on potential benefits Semantic Web technologies can bring to BPM. The authors will show how these technologies help automate the transition between the inherently separate/detached business professionals’ level and the IT level without the burden of additional knowledge acquisition on behalf of the business professionals. As background information they briefly discuss existing process modeling notations like the Business Process Modeling Notation (BPMN) as well as the execution centric Business Process Execution Language (BPEL), and their limitations in terms of proper support for the business professional. The chapter stresses on the added value Semantic Web technologies yield when leveraged for the benefit of BPM. For this the authors give examples of existing BPM techniques that can be improved by using Semantic Web technologies, as well as novel approaches which became possible only through the availability of semantic descriptions. They show how process model configuration can be automated and thus simplified and how flexibility during process execution is increased. Additionally, they present innovative techniques like automatic process composition and auto-completion of process models where suitable process fragments are automatically discovered to make up the process model. They also present a reference architecture of a BPM system that utilizes Semantic Web technologies in an SOA environment.},
   url = {http://www2.informatik.uni-stuttgart.de/cgi-bin/NCSTRL/NCSTRL_view.pl?id=INBOOK-2009-02&engl=0}
}