@article{MathesStoidnerSchwarzkopfetal., author = {Mathes, Markus and Stoidner, Christoph and Schwarzkopf, Roland and Heinzl, Steffen and D{\"o}rnemann, Tim and Dohmann, Helmut and Freisleben, Bernd}, title = {Time-constrained services: a framework for using real-time web services in industrial automation}, series = {Service Oriented Computing and Applications}, volume = {3}, journal = {Service Oriented Computing and Applications}, publisher = {Springer London}, pages = {239 -- 262}, abstract = {The use of web services in industrial automation, e.g. in fully automated production processes like car manufacturing, promises simplified interaction among the manufacturing devices due to standardized protocols and increased flexibility with respect to process implementation and reengineering. Moreover, the adoption of web services as a seamless communication backbone within the overall industrial enterprise has additional benefits, such as simplified interaction with suppliers and customers (i.e. horizontal integration) and avoidance of a break in the communication paradigm within the enterprise (i.e. vertical integration). The Time-Constrained Services (TiCS) framework is a development and execution environment that empowers automation engineers to develop, deploy, publish, compose, and invoke time-constrained web services. TiCS consists of four functional layers—tool support layer, real-time infrastructural layer, real-time service layer, and hardware layer—which contain several components to meet the demands of a web service based automation infrastructure. This article gives an overview of the TiCS framework. More precisely, the general design considerations and an architectural blueprint of the TiCS framework are presented. Subsequently, selected key components of the TiCS framework are discussed in detail: the SOAP4PLC engine for equipping programmable logic controllers with a web service interface, the SOAP4IPC engine for processing web services in real-time on industrial PCs, the WS-TemporalPolicy language for describing time constraints, and the TiCS Modeler for composing time-constrained web services into a time-constrained BPEL4WS workflow.}, language = {en} } @inproceedings{MathesSchwarzkopfDoernemannetal., author = {Mathes, Markus and Schwarzkopf, Roland and D{\"o}rnemann, Tim and Heinzl, Steffen and Freisleben, Bernd}, title = {Composition of Time-Constrained BPEL4WS Workflows Using the TiCS Modeler}, series = {13th IFAC Symposium on Information Control Problems in Manufacturing}, volume = {42}, booktitle = {13th IFAC Symposium on Information Control Problems in Manufacturing}, number = {4}, publisher = {Elsevier}, doi = {https://doi.org/10.3182/20090603-3-RU-2001.0104}, pages = {888 -- 893}, abstract = {The adoption of service-oriented architectures based on web services in industrial automation promises increased interoperability and exibility. Since the development and deployment of web services requires in-depth programming knowledge, adequate tools to ease the work of automation engineers are required. In particular, the orchestration of existing web services to workflows is a challenging task that is complicated by the fact that manufacturing processes have time constraints, especially real-time constraints. This paper presents the Time-Constrained Services (TiCS) Modeler that supports the assisted orchestration of BPEL4WS workflows with time constraints.}, language = {en} } @inproceedings{HeinzlMathesStadelmannetal., author = {Heinzl, Steffen and Mathes, Markus and Stadelmann, Thilo and Seiler, Dominik and Diegelmann, Marcel and Dohmann, Helmut and Freisleben, Bernd}, title = {The Web Service Browser: Automatic Client Generation and Efficient Data Transfer for Web Services}, series = {Proceedings of the 7th IEEE International Conference on Web Services}, booktitle = {Proceedings of the 7th IEEE International Conference on Web Services}, publisher = {IEEE Computer Society Press}, doi = {10.1109/ICWS.2009.22}, pages = {743 -- 750}, abstract = {Web services are supported by almost all major software vendors, but nevertheless there is still a certain barrier that prevents a broader user community to actually use them. The barrier is the lack of appropriate clients offered in conjunction with the services. This paper presents a Web Service Browser that automatically generates a dynamic user interface when the user browses to the location of the service description and additionally handles the invocation of the service. To ease the use of the service, the browser takes care of data management by using an implementation of the Flex-SwA architecture. Results are presented to the user in a human-readable manner. When the result contains multimedia data, an audio or video player is used to present the result. Use cases demonstrate the benefits of the browser. With the Web Service Browser, web services simply become a usable component offered in the WWW.}, language = {en} } @inproceedings{MathesStoidnerHeinzletal., author = {Mathes, Markus and Stoidner, Christoph and Heinzl, Steffen and Freisleben, Bernd}, title = {SOAP4PLC: Web Services for Programmable Logic Controllers}, series = {17th Euromicro International Conference on Parallel, Distributed, and Network-Based Processing}, booktitle = {17th Euromicro International Conference on Parallel, Distributed, and Network-Based Processing}, publisher = {IEEE Computer Society Press}, doi = {https://doi.org/10.1109/PDP.2009.42}, pages = {210 -- 219}, abstract = {The use of service-oriented architectures based on web services in the manufacturing layer of industrial enterprises yields vertical integration and promises increased interoperability and flexibility. Unfortunately, two main obstacles complicate the use of web services in the manufacturing layer. First, the hardware/software used in this layer differs from the hardware/software used in other layers. Second, the manufacturing layer is maintained by automation engineers who typically are not familiar with web services. This paper presents the first SOAP engine for programmable logic controllers to advance the use of web services in the manufacturing layer. The engine offers a low memory footprint to respect the low computational power of programmable logic controllers and allows to export web services automatically without intervention of an automation engineer.}, language = {en} } @article{MathesHeinzlSchwarzkopfetal., author = {Mathes, Markus and Heinzl, Steffen and Schwarzkopf, Roland and Freisleben, Bernd}, title = {F\&L-Grid: Eine generische Backup und Recovery Infrastruktur f{\"u}r das D-Grid}, series = {2. DFN-Forum Kommunikationstechnologien}, journal = {2. DFN-Forum Kommunikationstechnologien}, editor = {M{\"u}ller, P. and Neumair, B. and Rodosek, G. D.}, publisher = {Gesellschaft f{\"u}r Informatik e.V.}, address = {Bonn}, pages = {55 -- 67}, abstract = {Grid Computing wird oftmals zur Durchf{\"u}hrung zeitintensiver Experimente, die eine enorme Menge an Daten produzieren, verwendet. Da existierende Backup und Recovery L{\"o}sungen basierend auf GridFTP oder RFT detaillierte technische Kenntnisse bez{\"u}glich Konfiguration und Nutzung erfordern, sind diese nicht unbedingt f{\"u}r alle Anwender geeignet. Viele Wissenschaftler bevorzugen eine m{\"o}glichst einfache und bedienungsfreundliche L{\"o}sung, um ihre experimentellen Ergebnisse zu sichern. Das F\&L-Grid Projekt, welches die Entwicklung eines Grids f{\"u}r Forschung und Lehre beabsichtigt, ist ein Teil des D-Grid. Hauptziel von F\&L-Grid ist der Entwurf und die Entwicklung einer generischen Backup und Recovery Infrastruktur f{\"u}r beliebige Grid-Umgebungen. Dieser Beitrag diskutiert den aktuellen Projektstatus von F\&LGrid und skizziert den Entwurf und die Implementierung der generischen Backup und Recovery Infrastruktur.}, language = {de} } @inproceedings{MathesHeinzlFreisleben, author = {Mathes, Markus and Heinzl, Steffen and Freisleben, Bernd}, title = {Towards a Generic Backup and Recovery Infrastructure for the German D-Grid Initiative}, series = {Tagungsband der ITG/GI-Fachtagung Kommunikation in Verteilten Systemen (KiVS)}, booktitle = {Tagungsband der ITG/GI-Fachtagung Kommunikation in Verteilten Systemen (KiVS)}, publisher = {Springer}, pages = {229 -- 240}, abstract = {Grid computing is often used for conducting time-consuming experiments that produce large amounts of data. Since existing backup and recovery solutions based on GridFTP or RFT require in-depth knowledge, they are not suited for scientists who are not Grid computing experts. Most scientists prefer an easy to use solution to back up and recover their experimental results. The F\&L-Grid project (a Grid providing services for research and education) is part of the German Grid Initiative (D-Grid) and is aimed at the design and development of the first generic backup and recovery infrastructure suitable for arbitrary Grid environments. This paper presents the current status of the ongoing F\&L-Grid project and outlines the generic backup and recovery infrastructure in detail.}, language = {en} } @inproceedings{HeinzlMathesFreisleben, author = {Heinzl, Steffen and Mathes, Markus and Freisleben, Bernd}, title = {The Grid Browser: Improving Usability in Service-Oriented Grids by Automatically Generating Clients and Handling Data Transfers}, series = {Proceedings of the 4th IEEE International Conference on e-Sciencee}, booktitle = {Proceedings of the 4th IEEE International Conference on e-Sciencee}, publisher = {IEEE Computer Society Press}, doi = {10.1109/eScience.2008.19}, pages = {269 -- 276}, abstract = {This paper presents a grid browser as a familiar environment for accessing a service-oriented grid. To relieve the service developer from developing a graphical user interface and a grid service client, and to relieve the service provider from installing and maintaining a grid portal, the proposed grid browser can be used instead of a grid portal. A grid browser is a Web browser that renders WSDL files similar to HTML files. Surfing to the location of the WSDL description of a grid service results in the automatic generation of a graphical frontend in the grid browser which a user can easily fill out to invoke a service or submit a job. Furthermore, data transfers are integrated into the grid browser by integrating an implementation of the Flex-SwA architecture, such that data transmission and service invocation can be done efficiently in a single step. An implementation of the proposed grid browser to improve the usability of a service-oriented grid is presented. A use case points out the advantages of the grid browser.}, language = {en} } @inproceedings{MathesHeinzlFreisleben, author = {Mathes, Markus and Heinzl, Steffen and Freisleben, Bernd}, title = {Towards a time-constrained web service infrastructure for industrial automation}, series = {Proceedings of the 13th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)}, booktitle = {Proceedings of the 13th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)}, publisher = {IEEE Computer Society Press}, doi = {10.1109/ETFA.2008.4638496}, pages = {846 -- 853}, abstract = {This paper suggests to seamlessly adopt a service-oriented architecture based on Web services throughout an industrial enterprise as a standardized, homogeneous communication backbone, from the business layer down to the manufacturing layer. Since manufacturing processes typically have time constraints, especially real-time constraints, particular attention has to be paid to the description of such time constraints within a Web service and the timely execution of time-constrained Web services within the proposed infrastructure. Furthermore, an outline of the time-constrained services (TiCS) framework - a framework which empowers automation engineers to develop, deploy, publish, compose and invoke time-constrained services - and a prototypical implementation of two main components of the TiCS framework, namely the TiCS Wizards and the TiCS Real-time Repository, are presented.}, language = {en} } @inproceedings{MathesSchwarzkopfDoernemannetal., author = {Mathes, Markus and Schwarzkopf, Roland and D{\"o}rnemann, Tim and Heinzl, Steffen and Freisleben, Bernd}, title = {Orchestration of Time-Constrained BPEL4WS workflows}, series = {Proceedings of the 13th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)}, booktitle = {Proceedings of the 13th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA)}, publisher = {IEEE Computer Society Press}, doi = {10.1109/ETFA.2008.4638349}, pages = {1 -- 4}, abstract = {The adoption of service-oriented architectures based on Web services in industrial automation promises increased interoperability and flexibility. The orchestration of existing Web services to workflows is a challenging task which is complicated by the fact that manufacturing processes have time constraints, especially real-time constraints. This paper presents the time-constrained services (TiCS) Modeler which supports the assisted orchestration of BPEL4WS workflows with time constraints. The presented prototypical implementation is based on a formal derivation of the time constraints of a workflow.}, language = {en} } @inproceedings{MathesHeinzlFreisleben, author = {Mathes, Markus and Heinzl, Steffen and Freisleben, Bernd}, title = {WS-TemporalPolicy: A WS-Policy Extension for Describing Service Properties with Time Constraints}, series = {32nd Annual IEEE International Computer Software and Applications Conference}, booktitle = {32nd Annual IEEE International Computer Software and Applications Conference}, publisher = {IEEE Computer Society Press}, doi = {10.1109/COMPSAC.2008.105}, pages = {1180 -- 1186}, abstract = {A Web service has several functional properties (e.g. its operations) and non-functional properties (e.g. quality of service and security parameters). Functional properties are usually static, whereas non-functional properties are often dynamic and thus vary over time. To describe properties with time constraints, the paper introduces WS-TemporalPolicy. WS-TemporalPolicy empowers a service developer to attach a validity period to the properties described in a WS-policy. The generation, validation, storage and retrieval, and deployment process of temporal policies is supported by the Temporal Policy Runtime Environment. Implementation issues and two use cases are presented to illustrate the use of temporal policies.}, language = {en} } @inproceedings{HeinzlMathesFreisleben, author = {Heinzl, Steffen and Mathes, Markus and Freisleben, Bernd}, title = {A Web Service Communication Policy for Describing Non-standard Application Requirements}, series = {Proceedings of the 8th IEEE/IPSJ Symposium on Applications and the Internet (SAINT)}, booktitle = {Proceedings of the 8th IEEE/IPSJ Symposium on Applications and the Internet (SAINT)}, publisher = {IEEE Computer Society Press}, doi = {10.1109/SAINT.2008.14}, pages = {40 -- 47}, abstract = {Web services are not really suitable for implementing applications with non-standard communication requirements, such as e.g. applications with data streaming and/or realtime requirements, applications depending on the transfer of large files, and legacy applications with complex message exchange patterns. This paper presents a communication policy for Web services based on WS-Policy, which enables the description of real-time and data streaming requirements, of file transfers, and of protocols and clients used by legacy applications. It is used in addition to the WSDL description of a service, and thus complements the service description by exposing the protocols used by the applications for the various requirements. By investigating a video-on-demand application, several limits of Web service technologies and the benefits of using the communication policy to describe such requirements are illustrated.}, language = {en} } @inproceedings{SchwarzkopfMathesHeinzletal., author = {Schwarzkopf, Roland and Mathes, Markus and Heinzl, Steffen and Freisleben, Bernd and Dohmann, Helmut}, title = {Java RMI versus .NET Remoting Architectural Comparison and Performance Evaluation}, series = {Proceedings of the 7th International Conference on Networking (ICN)}, booktitle = {Proceedings of the 7th International Conference on Networking (ICN)}, publisher = {IEEE Computer Society Press}, doi = {10.1109/ICN.2008.88}, pages = {398 -- 407}, abstract = {The implementation of distributed applications can be based on a multiplicity of technologies, e.g. plain sockets, Remote Procedure Call (RPC), Remote Method Invocation (RMI), Java Message Service (JMS), .NET Remoting, or Web Services. These technologies differ widely in complexity, interoperability, standardization, and ease of use. To achieve the highest efficiency, the use of plain sockets is advisable, whereas highest interoperability and standardization argue for Web Services. Real world applications requirements are a trade-off between efficiency, development costs, usability, reliability, interoperability, and so on. For example, a multimedia streaming application requires high performance to avoid delays, whereas Internet trading platforms depend on high interoperability, reliability and availability. Since Java RMI and .NET Remoting support fast development of highly efficient applications, many developers choose one of these technologies to realize their applications. Besides differences in design, the two technologies offer diverse performance characteristics. This paper has two main contributions: (1) a comparison of the design and architecture of Java RMI and .NET Remoting is presented, (2) an experimental performance analysis with respect to various aspects of both technologies is conducted.}, language = {en} } @inproceedings{DoernemannHeinzlDoernemannetal., author = {D{\"o}rnemann, Tim and Heinzl, Steffen and D{\"o}rnemann, Kay and Mathes, Markus and Smith, Matthew and Freisleben, Bernd}, title = {Secure Grid Service Engineering for Industrial Optimization}, series = {Proceedings of the 7th International Conference on Optimization: Techniques and Applications (ICOTA)}, booktitle = {Proceedings of the 7th International Conference on Optimization: Techniques and Applications (ICOTA)}, pages = {371 -- 372}, language = {en} } @inproceedings{HeinzlMathesFrieseetal., author = {Heinzl, Steffen and Mathes, Markus and Friese, Thomas and Smith, Matthew and Freisleben, Bernd}, title = {Flex-SwA: Flexible Exchange of Binary Data Based on SOAP Messages with Attachments}, series = {2006 IEEE International Conference on Web Services (ICWS'06)}, booktitle = {2006 IEEE International Conference on Web Services (ICWS'06)}, publisher = {IEEE Computer Society Press}, doi = {10.1109/ICWS.2006.65}, pages = {3 -- 10}, abstract = {SOAP is the standard protocol for message exchange in Web service environments. As an XML-based protocol, SOAP is not suitable for the transmission of large amounts of binary data. This fact has been addressed by the SOAP messages with attachments specification, which regulates the transfer of a SOAP message together with an arbitrary number of binary attachments composed within a MIME multipart/related message. Although this leads to a reduction of transmission overhead, Web service communication using SOAP messages with attachments still lacks communication and processing flexibility. In this paper, we present a novel and more flexible way of handling attachments in SOAP-based Web service environments. In contrast to SOAP messages with attachments, our approach offers message forwarding without additional communication cost and demand-driven evaluation and transmission of binary data, thus providing the opportunity to save time by overlapping service execution and data transmission}, language = {en} } @inproceedings{MathesHeinzlFrieseetal., author = {Mathes, Markus and Heinzl, Steffen and Friese, Thomas and Freisleben, Bernd}, title = {Enabling Post-Invocation Parameter Transmission in Service-Oriented Environments}, series = {International conference on Networking and Services (ICNS'06)}, booktitle = {International conference on Networking and Services (ICNS'06)}, publisher = {IEEE Computer Society Press}, doi = {10.1109/ICNS.2006.44}, pages = {55 -- 62}, abstract = {This paper addresses two drawbacks associated with using SOAP RPC to invoke services in service-oriented environments. First, overlapping of parameter production, parameter transmission and service execution is not possible, since all parameters of a service call have to exist prior to service invocation; until all parameters are available, a service caller has to defer service invocation. Second, the XML format of SOAP is not suitable to transfer large binary parameters, because encoding consumes a considerable amount of time. In this paper, a new approach to invoke Web services is presented, which enables post-invocation parameter transmission and efficient transmission of binary parameters, thus enabling the overlapping of parameter production, parameter transmission and service execution to reduce the overall processing time. To realize post-invocation parameter transmission, an extension of WSDL is proposed. It is shown how post-invocation parameter transmission enables the efficient implementation of stream-based production/consumption of parameters and pipelining. Furthermore, measurement results are presented demonstrating a noticeable performance gain}, language = {en} } @book{HeinzlMathes, author = {Heinzl, Steffen and Mathes, Markus}, title = {Middleware in Java}, series = {IT-Professional}, journal = {IT-Professional}, publisher = {Vieweg+Teubner Verlag}, address = {Wiesbaden}, isbn = {978-3-528-05912-5}, doi = {10.1007/978-3-322-80262-0}, pages = {280}, abstract = {Dieses Buch vermittelt beispielhaft das notwendige Know-how zum Entwurf und zur Entwicklung verteilter Anwendungen. Die Umsetzung erfolgt mittels der relevanten Middleware-Technologien in Java. Die Darstellung erfolgt nachvollziehbar anhand praxisnaher Beispiele, Aufgaben helfen das Gelernte aktiv einzu{\"u}ben. Der Quellcode der vorgestellten Programme und Pr{\"a}sentationen zur Unterst{\"u}tzung von Dozenten und Studenten werden zum Download angeboten. Als besonderer Service f{\"u}r Dozenten werden auch die L{\"o}sungen zu den Aufgaben bereitgestellt.}, language = {de} } @inproceedings{StadelmannHeinzlUnterbergeretal., author = {Stadelmann, Thilo and Heinzl, Steffen and Unterberger, Markus and Freisleben, Bernd}, title = {WebVoice: A Toolkit for Perceptual Insights into Speech Processing}, series = {Proceedings of the 2nd International Conf. on Image and Signal Processing (CISP)}, booktitle = {Proceedings of the 2nd International Conf. on Image and Signal Processing (CISP)}, publisher = {IEEE Press}, pages = {4358 -- 4362}, language = {en} } @inproceedings{SeilerEwerthHeinzletal., author = {Seiler, Dominik and Ewerth, Ralph and Heinzl, Steffen and Stadelmann, Thilo and M{\"u}hling, Markus and Freisleben, Bernd and Grauer, Manfred}, title = {Eine service-orientierte Grid-Infrastruktur zur Unterst{\"u}tzung medienwissenschaftlicher Filmanalyse}, series = {Proceedings of the GeNeMe Workshop 2009}, booktitle = {Proceedings of the GeNeMe Workshop 2009}, publisher = {TUDpress}, pages = {79 -- 89}, language = {de} } @article{MathesStoidnerSchwarzkopfetal., author = {Mathes, Markus and Stoidner, Christoph and Schwarzkopf, Roland and Heinzl, Steffen and D{\"o}rnemann, Tim and Dohmann, Helmut and Freisleben, Bernd}, title = {Time-Constrained Services (TiCS): A Framework for Using Real-time WS in Industrial Automation}, series = {Service Oriented Computing and Applications (SOCA) Journal}, volume = {3}, journal = {Service Oriented Computing and Applications (SOCA) Journal}, number = {4}, publisher = {Springer}, address = {London}, pages = {239 -- 262}, language = {en} } @inproceedings{HeinzlMathesStadelmannetal., author = {Heinzl, Steffen and Mathes, Markus and Stadelmann, Thilo and Seiler, Dominik and Diegelmann, Marcel and Dohmann, Helmut and Freisleben, Bernd}, title = {The Web Service Browser: Automatic Client Generation and Efficient Data Transfer for Web Services}, series = {Proceedings of the 7th IEEE Int'l Conf. on Web Services (ICWS)}, booktitle = {Proceedings of the 7th IEEE Int'l Conf. on Web Services (ICWS)}, publisher = {IEEE Press}, pages = {743 -- 750}, language = {en} } @phdthesis{Heinzl, author = {Heinzl, Steffen}, title = {Policies for Web Services}, pages = {204}, language = {en} } @inproceedings{MathesSchwarzkopfDoernemannetal., author = {Mathes, Markus and Schwarzkopf, Roland and D{\"o}rnemann, Tim and Heinzl, Steffen and Freisleben, Bernd}, title = {Composition of Time-Constrained BPEL4WS Workflows Using the TiCS Modeler}, series = {Proceedings of the 13th IFAC Symposium on Information Control Problems in Manufacturing (INCOM)}, booktitle = {Proceedings of the 13th IFAC Symposium on Information Control Problems in Manufacturing (INCOM)}, publisher = {Elsevier}, pages = {892 -- 897}, language = {en} } @inproceedings{MathesHeinzlSchwarzkopfetal., author = {Mathes, Markus and Heinzl, Steffen and Schwarzkopf, Roland and Freisleben, Bernd}, title = {F\&L-Grid: Eine generische Backup und Recovery Infrastruktur}, series = {Tagungsband des 2. DNF-Forum Kommunikationstechnologien}, booktitle = {Tagungsband des 2. DNF-Forum Kommunikationstechnologien}, publisher = {Gesellschaft f{\"u}r Informatik (GI)}, pages = {55 -- 67}, language = {de} } @inproceedings{MathesHeinzlFreisleben, author = {Mathes, Markus and Heinzl, Steffen and Freisleben, Bernd}, title = {SOAP4PLC: Web Services for Programmable Logic Controllers}, series = {Proceedings of the 17th Euromicro Int'l Conf. on Parallel, Distributed, and Network-Based Processing (PDP)}, booktitle = {Proceedings of the 17th Euromicro Int'l Conf. on Parallel, Distributed, and Network-Based Processing (PDP)}, publisher = {IEEE Press}, pages = {210 -- 219}, language = {en} } @article{SchmelingHeinzl, author = {Schmeling, Benjamin and Heinzl, Steffen}, title = {JSF 2.2 - Quo vadis?}, series = {Java Magazin}, journal = {Java Magazin}, number = {6}, publisher = {S\&S Media}, issn = {1619-795X}, pages = {28 -- 33}, language = {de} } @article{SchmelingCharfiHeinzletal., author = {Schmeling, Benjamin and Charfi, Anis and Heinzl, Steffen and Mezini, Mira}, title = {A Survey on Non-functional Concerns in Web Services}, series = {International Journal of Web Information Systems}, volume = {8}, journal = {International Journal of Web Information Systems}, number = {1}, publisher = {Emerald Group Publishing Limited}, pages = {5 -- 31}, language = {en} } @incollection{HeinzlKylauMay, author = {Heinzl, Steffen and Kylau, Uwe and May, Norman}, title = {Modeling Foundations}, series = {Handbook of Service Description: USDL and Its Methods}, booktitle = {Handbook of Service Description: USDL and Its Methods}, publisher = {Springer}, isbn = {978-1-4614-1863-4}, pages = {327 -- 356}, language = {en} } @incollection{DuddyHeinrichHeinzletal., author = {Duddy, Keith and Heinrich, Matthias and Heinzl, Steffen and Knechtel, Martin and Pedrinaci, Carlos and Schmeling, Benjamin and Smith, Virginia}, title = {Representing USDL for Humans and Tools}, series = {Handbook of Service Description: USDL and Its Methods}, booktitle = {Handbook of Service Description: USDL and Its Methods}, publisher = {Springer}, isbn = {978-1-4614-1863-4}, pages = {357 -- 384}, language = {en} } @inproceedings{HeinzlSeilerUnterbergeretal., author = {Heinzl, Steffen and Seiler, Dominik and Unterberger, Marco and Nonenmacher, A. and Freisleben, Bernd}, title = {MIRO: A Mashup Editor Leveraging Web, Grid and Cloud Services}, series = {Proceedings of the 11th Int'l Conf. on Information Integration and Web-based Applications \& Services (iiWAS)}, booktitle = {Proceedings of the 11th Int'l Conf. on Information Integration and Web-based Applications \& Services (iiWAS)}, publisher = {ACM and OCG}, pages = {15 -- 22}, language = {en} } @inproceedings{HeinzlSeilerJuhnkeetal., author = {Heinzl, Steffen and Seiler, Dominik and Juhnke, Ernst and Freisleben, Bernd}, title = {Exposing Validity Periods of Prices for Resource Consumption to Web Service Users via Temporal Policies}, series = {Proceedings of the 11th Int'l Conf. on Information Integration and Web-based Applications \& Services (iiWAS)}, booktitle = {Proceedings of the 11th Int'l Conf. on Information Integration and Web-based Applications \& Services (iiWAS)}, publisher = {ACM and OCG}, pages = {233 -- 240}, language = {en} } @incollection{HellerSchmelingHeinzletal., author = {Heller, Markus and Schmeling, Benjamin and Heinzl, Steffen and Leidig, Torsten and Duddy, Keith and Sandfuchs, Thorsten and Klein, Andreas and Allgaier, Matthias}, title = {Enabling USDL by Tools}, series = {Handbook of Service Description: USDL and Its Methods}, booktitle = {Handbook of Service Description: USDL and Its Methods}, publisher = {Springer}, pages = {385 -- 414}, language = {en} } @incollection{BarrosOberleKylauetal., author = {Barros, Alistair and Oberle, Daniel and Kylau, Uwe and Heinzl, Steffen}, title = {Design Overview of USDL}, series = {Handbook of Service Description: USDL and Its Methods}, booktitle = {Handbook of Service Description: USDL and Its Methods}, publisher = {Springer}, isbn = {978-1-4614-1863-4}, pages = {187 -- 226}, language = {en} } @article{HeinzlSchmeling, author = {Heinzl, Steffen and Schmeling, Benjamin}, title = {Unified Service Description Language}, series = {Java Magazin}, journal = {Java Magazin}, number = {2}, publisher = {S\&S Media}, issn = {1619-795X}, pages = {98 -- 102}, language = {de} } @techreport{BarrosBaumannCharfietal., author = {Barros, Alistair and Baumann, Christian and Charfi, Anis and Heinzl, Steffen and Kiemes, Tom and Kylau, Uwe and May, Norman and M{\"u}ller, Oliver and Novelli, Francesco and Oberle, Daniel and Robinson, Philip and Schmeling, Benjamin and Theilmann, Wolfgang and Witteborg, Heiko}, title = {Unified Service Description Language (USDL) - Functional Module, Version 3.0, Milestone M5, Technical Report}, publisher = {SAP Research}, language = {en} } @techreport{BarrosBaumannCharfietal., author = {Barros, Alistair and Baumann, Christian and Charfi, Anis and Heinzl, Steffen and Kiemes, Tom and Kylau, Uwe and May, Norman and M{\"u}ller, Oliver and Novelli, Francesco and Oberle, Daniel and Robinson, Philip and Schmeling, Benjamin and Theilmann, Wolfgang and Witteborg, Heiko}, title = {Unified Service Description Language (USDL) - Interaction Module, Version 3.0, Milestone M5, Technical Report}, publisher = {SAP Research}, language = {en} } @techreport{BarrosBaumannCharfietal., author = {Barros, Alistair and Baumann, Christian and Charfi, Anis and Heinzl, Steffen and Kiemes, Tom and Kylau, Uwe and May, Norman and M{\"u}ller, Oliver and Novelli, Francesco and Oberle, Daniel and Robinson, Philip and Schmeling, Benjamin and Theilmann, Wolfgang and Witteborg, Heiko}, title = {Unified Service Description Language (USDL) - Technical Module, Version 3.0, Milestone M5, Technical Report}, publisher = {SAP Research}, language = {en} } @techreport{BarrosBaumannCharfietal., author = {Barros, Alistair and Baumann, Christian and Charfi, Anis and Fl{\"u}gge, M. and Heinzl, Steffen and Kiemes, Tom and Kylau, Uwe and Marienfeld, F. and May, Norman and M{\"u}ller, Oliver and Novelli, Francesco and Oberle, Daniel and Pattberg, J. and Robinson, Philip and Schmeling, Benjamin and Theilmann, Wolfgang and Witteborg, Heiko and Finzen, J. and Horch, A. and Kintz, M.}, title = {Unified Service Description Language (USDL) - Service Module, Version 3.0, Milestone M5, Technical Report}, publisher = {SAP Research}, language = {en} } @techreport{BarrosBaumannCharfietal., author = {Barros, Alistair and Baumann, Christian and Charfi, Anis and Fl{\"u}gge, M. and Heinzl, Steffen and Kiemes, Tom and Kylau, Uwe and Marienfeld, F. and May, Norman and M{\"u}ller, Oliver and Novelli, Francesco and Oberle, Daniel and Pattberg, J. and Robinson, Philip and Schmeling, Benjamin and Theilmann, Wolfgang and Witteborg, Heiko and Finzen, J. and Horch, A. and Kintz, M.}, title = {Unified Service Description Language (USDL) - Foundation, Version 3.0, Milestone M5, Technical Report}, publisher = {SAP Research}, language = {en} } @techreport{BarrosBaumannCharfietal., author = {Barros, Alistair and Baumann, Christian and Charfi, Anis and Finzen, J. and Fl{\"u}gge, M. and Heinzl, Steffen and Kiemes, Tom and Kylau, Uwe and Marienfeld, F. and May, Norman and M{\"u}ller, Oliver and Novelli, Francesco and Oberle, Daniel and Pattberg, J. and Robinson, Philip and Schmeling, Benjamin and Theilmann, Wolfgang and Witteborg, Heiko}, title = {Unified Service Description Language (USDL) - Service Level (SLA) Module, Version 3.0, Milestone M5}, publisher = {SAP Research}, language = {en} } @misc{BarrosBaumannCharfietal., author = {Barros, Alistair and Baumann, Christian and Charfi, Anis and Heinzl, Steffen and Kiemes, Tom and Kylau, Uwe and May, Norman and M{\"u}ller, Oliver and Novelli, Francesco and Oberle, Daniel and Robinson, Philip and Schmeling, Benjamin and Theilmann, Wolfgang and Witteborg, Heiko}, title = {Unified Service Description Language (USDL) - Pricing Module, Version 3.0, Milestone M5, Technical Report}, publisher = {SAP Research}, language = {en} } @inproceedings{MathesHeinzlFreisleben, author = {Mathes, Markus and Heinzl, Steffen and Freisleben, Bernd}, title = {WS-TemporalPolicy: A WS-Policy Extension for Describing Service Properties with Time Constraints}, series = {Proceedings of the First IEEE Int'l Workshop On Real-Time Service-Oriented Architecture and Applications (RTSOAA 2008) of the 32nd IEEE Computer Software and Applications Conf. (COMPSAC 2008)}, booktitle = {Proceedings of the First IEEE Int'l Workshop On Real-Time Service-Oriented Architecture and Applications (RTSOAA 2008) of the 32nd IEEE Computer Software and Applications Conf. (COMPSAC 2008)}, publisher = {IEEE Press}, pages = {1180 -- 1186}, language = {en} } @article{HeinzlSeilerJuhnkeetal., author = {Heinzl, Steffen and Seiler, Dominik and Juhnke, Ernst and Stadelmann, Thilo and Ewerth, Ralph and Grauer, Manfred and Freisleben, Bernd}, title = {A Scalable Service-Oriented Architecture for Multimedia Analysis, Synthesis, and Consumption}, series = {International Journal of Web and Grid Services}, volume = {5}, journal = {International Journal of Web and Grid Services}, number = {3}, publisher = {Inderscience Publishers}, pages = {219 -- 260}, language = {en} } @inproceedings{SeilerHeinzlJuhnkeetal., author = {Seiler, Dominik and Heinzl, Steffen and Juhnke, Ernst and Ewerth, Ralph and Grauer, Manfred and Freisleben, Bernd}, title = {Efficient Data Transmission in Service Workflows for Distributed Video Content Analysis}, series = {Proc. of the 6th Int'l Conf. on Advances in Mobile Computing \& Multimedia}, booktitle = {Proc. of the 6th Int'l Conf. on Advances in Mobile Computing \& Multimedia}, publisher = {ACM Press and OCG}, pages = {7 -- 14}, language = {en} } @techreport{BarrosBaumannCharfietal., author = {Barros, Alistair and Baumann, Christoph and Charfi, Anis and Heinzl, Steffen and Kiemes, Tom and Kylau, Uwe and May, Norman and M{\"u}ller, Oliver and Novelli, Francesco and Oberle, Daniel and Robinson, Philip and Schmeling, Benjamin and Theilmann, Wolfgang and Witteborg, Heiko}, title = {Unified Service Description Language (USDL) - Participants Module, Version 3.0, Milestone M5, Technical Report}, publisher = {SAP Research}, language = {en} } @article{HeinzlSchmelingFreisleben, author = {Heinzl, Steffen and Schmeling, Benjamin and Freisleben, Bernd}, title = {Using Temporal Policies for Managing Changing Meta-Data of Web Services}, series = {International Journal of Web and Grid Services}, volume = {6}, journal = {International Journal of Web and Grid Services}, number = {4}, publisher = {Inderscience Publishers}, pages = {331 -- 356}, language = {en} } @article{SchmelingHeinzlWitteborg, author = {Schmeling, Benjamin and Heinzl, Steffen and Witteborg, Heiko}, title = {Model-relational Mapping}, series = {Java Magazin}, journal = {Java Magazin}, number = {11}, publisher = {S\&S Media}, issn = {1619-795X}, pages = {64 -- 70}, language = {en} } @inproceedings{HeinzlSchmeling, author = {Heinzl, Steffen and Schmeling, Benjamin}, title = {Using XML schema to improve writing, validation, and structure of WS-Policies}, series = {Proceedings of the ACM Symposium on Applied Computing (SAC)}, booktitle = {Proceedings of the ACM Symposium on Applied Computing (SAC)}, number = {3}, publisher = {ACM Press}, pages = {2422 -- 2429}, language = {en} } @article{HeinzlNonenmacherFreisleben, author = {Heinzl, Steffen and Nonenmacher, A. and Freisleben, Bernd}, title = {Mashups in Flex, Part 2}, series = {Java Magazin}, journal = {Java Magazin}, number = {4}, publisher = {S\&S Media}, issn = {1619-795X}, pages = {54 -- 58}, language = {en} } @book{Heinzl, author = {Heinzl, Steffen}, title = {Policies for Web Services: Improving the Description of Services}, publisher = {SVH - S{\"u}dwestdeutscher Verlag f{\"u}r Hochschulschriften}, isbn = {3-838-11446-9}, pages = {204}, language = {en} } @article{HeinzlNonenmacherFreisleben, author = {Heinzl, Steffen and Nonenmacher, A. and Freisleben, Bernd}, title = {Mashups in Flex, Part 1}, series = {Java Magazin}, journal = {Java Magazin}, number = {3}, publisher = {S\&S Media}, issn = {1619-795X}, pages = {54 -- 59}, language = {en} } @inproceedings{HoffmannBrandHeinzl, author = {Hoffmann, Christian and Brand, Christoph and Heinzl, Steffen}, title = {Towards an Architecture for End-to-End-Encrypted File Synchronization Systems}, series = {Proceedings of the 24th IEEE Int'l Conf. on Enabling Technologies: Infrastructures for Collaborative Enterprises (WETICE)}, booktitle = {Proceedings of the 24th IEEE Int'l Conf. on Enabling Technologies: Infrastructures for Collaborative Enterprises (WETICE)}, publisher = {IEEE Press}, pages = {170 -- 175}, language = {en} } @book{Heinzl, author = {Heinzl, Steffen}, title = {Java {\"U}bungen 2: Mehr als 50 erprobte {\"U}bungen f{\"u}r das zweite Semester Programmieren in Java}, edition = {1. Auflage}, publisher = {KDP}, pages = {195}, abstract = {In diesem Buch finden Sie mehr als 50 erprobte {\"U}bungsaufgaben, die Ihnen dabei helfen, die objektorientierte Programmierung in Java zu erlernen. Das Buch richtet sich an Studierende des zweiten Semesters, die Programmieren in Java lernen. Dabei zielen die {\"U}bungen auf die objektorientierte Programmierung ab. Die letzten Lektionen des Buchs stellen einige {\"U}bungsaufgaben zur Verf{\"u}gung, um einen Einstieg in die funktionale Programmierung in Java zu erhalten. Das Buch verzichtet bewusst auf Musterl{\"o}sungen.}, language = {de} } @inproceedings{HeinzlSchreibmann, author = {Heinzl, Steffen and Schreibmann, Vitaliy}, title = {Function References as First Class Citizens in UML Class Modeling}, series = {Proceedings of the 13th International Conference on Evaluation of Novel Approaches to Software Engineering (ENASE)}, booktitle = {Proceedings of the 13th International Conference on Evaluation of Novel Approaches to Software Engineering (ENASE)}, publisher = {Scitepress}, pages = {335 -- 342}, abstract = {There have been a number of philosophical discussions whether functional programming or object-oriented programming is the better programming concept. In reality, programmers utilize both concepts and functional programming concepts improve object-oriented languages. Likewise the modeling of OO languages should also reflect these concepts in the modeling process. This paper improves the modeling of behavior (usually expressed through functional programming) in UML class diagrams. In UML class diagrams, behavior modeling is only achieved by modeling a new class containing the desired function. If several alternatives for a certain behavior have to be expressed, the modeling complexity increases because we need to introduce an interface and for each alternative an additional class. Therefore, we propose a new function element that circumvents these problems and reduces the complexity of the model. Due to the proposed <> stereotype, functions in the model can be identified at first glance. The new model is motivated by the strategy pattern and evaluated against a more complex design pattern. A possible first implementation is presented.}, language = {en} } @inproceedings{HeinzlMetz, author = {Heinzl, Steffen and Metz, Christoph}, title = {Toward a Cloud-ready Dynamic Load Balancer based on the Apache Web Server}, series = {Proceedings of the 22nd IEEE Int'l Conf. on Enabling Technologies: Infrastructures for Collaborative Enterprises (WETICE)}, booktitle = {Proceedings of the 22nd IEEE Int'l Conf. on Enabling Technologies: Infrastructures for Collaborative Enterprises (WETICE)}, publisher = {IEEE Press}, pages = {342 -- 345}, abstract = {Perhaps, the most interesting part of Cloud Computing is rapid elasticity. To be able to exploit the elasticity of a cloud infrastructure, the applications usually need to be able to scale horizontally, i.e. it must be possible to add (and also remove) nodes offering the same capabilities as the existing ones. In such scenarios, a load balancer is usually used. To keep the manual labor down, the load balancer should automatically be able to distribute load to the newly added nodes. In this paper, we show how to transform the popular Apache Web Server (which is only able to act as a static load balancer) into a dynamic cloud-ready load balancer.}, language = {en} } @book{Heinzl, author = {Heinzl, Steffen}, title = {Java {\"U}bungen: Mehr als 80 erprobte {\"U}bungen f{\"u}r das erste Semester Programmieren in Java}, publisher = {KDP}, isbn = {979-8-6237-4000-7}, pages = {138}, abstract = {In diesem Buch finden Sie {\"u}ber 80 erprobte {\"U}bungsaufgaben, die Ihnen dabei helfen, Programmieren zu erlernen. Das Buch richtet sich an Studierende des ersten Semesters, die Programmieren in Java lernen. Dabei zielen die {\"U}bungen zun{\"a}chst auf die prozedurale Programmierung ab, bevor die Br{\"u}cke zur objektorientierten Programmierung geschlagen wird. Das Buch verzichtet bewusst auf Musterl{\"o}sungen.}, language = {de} } @article{HeinzlSchmelingFranke, author = {Heinzl, Steffen and Schmeling, Benjamin and Franke, Jonas}, title = {Eclipse, E-Commerce und EC2}, series = {Eclipse Magazin}, journal = {Eclipse Magazin}, number = {4}, publisher = {S\&S Media}, issn = {1861-2296}, pages = {67 -- 72}, language = {de} } @article{HeinzlSchmelingEder, author = {Heinzl, Steffen and Schmeling, Benjamin and Eder, Niko}, title = {Automatisches Skalieren in der Amazon Cloud}, series = {Java Magazin}, journal = {Java Magazin}, number = {8}, publisher = {S\&S Media}, issn = {1619-795X}, pages = {50 -- 55}, language = {de} } @article{OberleBarrosKylauetal., author = {Oberle, Daniel and Barros, Alistair and Kylau, Uwe and Heinzl, Steffen}, title = {A unified description language for human to automated services}, series = {Information Systems}, volume = {38}, journal = {Information Systems}, number = {1}, publisher = {Elsevier}, pages = {155 -- 181}, language = {en} } @article{FlorianHeinzl, author = {Florian, Marcel and Heinzl, Steffen}, title = {Watson, reden Sie mit mir!}, series = {Java Magazin}, journal = {Java Magazin}, number = {8}, publisher = {S\&S Media}, issn = {1619-795X}, pages = {31 -- 37}, language = {de} }