@techreport{HertelKenneckeReicheetal.2024, author = {Hertel, Kyra and Kennecke, Andreas and Reiche, Michael and Schmidt-Kopplin, Diana and Tillmann, Diana and Winkler, Marco}, title = {Bericht zum Auftaktworkshop des Forschungsprojektes "Workflow-Management-Systeme f{\"u}r Open-Access-Hochschulverlage (OA-WFMS)"}, doi = {10.25932/publishup-63805}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-638057}, year = {2024}, abstract = {Das Forschungsprojekt „Workflow-Management-Systeme f{\"u}r Open-Access-Hochschulverlage (OA-WFMS)" ist eine Kooperation zwischen der HTWK Leipzig und der Universit{\"a}t Potsdam. Ziel ist es, die Bedarfe von Universit{\"a}ts- und Hochschulverlagen und Anforderungen an ein Workflow-Management-Systeme (WFMS) zu analysieren, um daraus ein generisches Lastenheft zu erstellen. Das WFMS soll den Publikationsprozess in OA-Verlagen erleichtern, beschleunigen sowie die Verbreitung von Open Access und das nachhaltige, digitale wissenschaftliche Publizieren f{\"o}rdern. Das Projekt baut auf den Ergebnissen der Projekte „Open-Access-Hochschulverlag (OA-HVerlag)" und „Open-Access-Strukturierte-Kommunikation (OA-STRUKTKOMM)" auf. Der diesem Bericht zugrunde liegende Auftaktworkshop fand 2024 in Leipzig mit Vertreter:innen von zehn Institutionen statt. Der Workshop diente dazu, Herausforderungen und Anforderungen an ein WFMS zu ermitteln sowie bestehende L{\"o}sungsans{\"a}tze und Tools zu diskutieren. Im Workshop wurden folgende Fragen behandelt: a. Wie kann die Organisation und {\"U}berwachung von Publikationsprozessen in wissenschaftlichen Verlagen durch ein WFMS effizient gestaltet werden? b. Welche Anforderungen muss ein WFMS erf{\"u}llen, um Publikationsprozesse optimal zu unterst{\"u}tzen? c. Welche Schnittstellen m{\"u}ssen ber{\"u}cksichtigt werden, um die Interoperabilit{\"a}t der Systeme zu garantieren? d. Welche bestehenden L{\"o}sungsans{\"a}tze und Tools sind bereits im Einsatz und welche Vor- und Nachteile haben diese? Der Workshop gliederte sich in zwei Teile : Teil 1 behandelte Herausforderungen und Anforderungen (Fragen a. bis c.), Teil 2 bestehende L{\"o}sungen und Tools (Frage d.). Die Ergebnisse des Workshops fließen in die Bedarfsanalyse des Forschungsprojekts ein. Die im Bericht dokumentierten Ergebnisse zeigen die Vielzahl der Herausforderungen der bestehenden Ans{\"a}tze bez{\"u}glich des OA-Publikationsmanagements . Die Herausforderungen zeigen sich insbesondere bei der Systemheterogenit{\"a}t, den individuellen Anpassungsbedarfen und der Notwendigkeit der systematischen Dokumentation. Die eingesetzten Unterst{\"u}tzungssysteme und Tools wie Dateiablagen, Projektmanagement- und Kommunikationstools k{\"o}nnen insgesamt den Anforderungen nicht gen{\"u}gen, f{\"u}r Teill{\"o}sungen sind sie jedoch nutzbar. Deshalb muss die Integration bestehender Systeme in ein zu entwickelndes OA-WFMS in Betracht gezogen und die Interoperabilit{\"a}t der miteinander interagierenden Systeme gew{\"a}hrleistet werden. Die Beteiligten des Workshops waren sich einig, dass das OA-WFMS flexibel und modular aufgebaut werden soll. Einer konsortialen Softwareentwicklung und einem gemeinsamen Betrieb im Verbund wurde der Vorrang gegeben. Der Workshop lieferte wertvolle Einblicke in die Arbeit der Hochschulverlage und bildet somit eine solide Grundlage f{\"u}r die in Folge zu erarbeitende weitere Bedarfsanalyse und die Erstellung des generischen Lastenheftes.}, language = {de} } @article{Hildebrandt2016, author = {Hildebrandt, Dieter}, title = {Image-based styling}, series = {The Visual Computer}, volume = {32}, journal = {The Visual Computer}, publisher = {Springer}, address = {New York}, issn = {0178-2789}, doi = {10.1007/s00371-015-1073-3}, pages = {445 -- 463}, year = {2016}, abstract = {The same data can be visualized using various visual styles that each is suitable for specific requirements, e.g., 3D geodata visualized using photorealistic, cartographic, or illustrative styles. In contrast to feature-based styling, image-based styling performed in image space at image resolution allows decoupling styling from image generation and output-sensitive, expressive styling. However, leveraging image-based styling is still impeded. No previous approach allows specifying image-based styling expressively with an extensive inventory of composable operators, while providing styling functionality in a service-oriented, interoperable manner. In this article, we present an interactive system for specifying and providing the functionality of image-based styling. As key characteristics, it separates concerns of styling from image generation and facilitates specifying styling as algebraic compositions of high-level operators using a unified 3D model representation. We propose a generalized visualization model, an image-based styling algebra, two declarative DSLs, an operator taxonomy, an operational model, and a standards-based service interface. The approach facilitates expressive specifications of image-based styling for design, description, and analysis and leveraging the functionality of image-based styling in a service-oriented, interoperable, reusable, and composable manner.}, language = {en} } @phdthesis{Sahlmann2021, author = {Sahlmann, Kristina}, title = {Network management with semantic descriptions for interoperability on the Internet of Things}, doi = {10.25932/publishup-52984}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-529846}, school = {Universit{\"a}t Potsdam}, pages = {x, 272}, year = {2021}, abstract = {The Internet of Things (IoT) is a system of physical objects that can be discovered, monitored, controlled, or interacted with by electronic devices that communicate over various networking interfaces and eventually can be connected to the wider Internet. [Guinard and Trifa, 2016]. IoT devices are equipped with sensors and/or actuators and may be constrained in terms of memory, computational power, network bandwidth, and energy. Interoperability can help to manage such heterogeneous devices. Interoperability is the ability of different types of systems to work together smoothly. There are four levels of interoperability: physical, network and transport, integration, and data. The data interoperability is subdivided into syntactic and semantic data. Semantic data describes the meaning of data and the common understanding of vocabulary e.g. with the help of dictionaries, taxonomies, ontologies. To achieve interoperability, semantic interoperability is necessary. Many organizations and companies are working on standards and solutions for interoperability in the IoT. However, the commercial solutions produce a vendor lock-in. They focus on centralized approaches such as cloud-based solutions. This thesis proposes a decentralized approach namely Edge Computing. Edge Computing is based on the concepts of mesh networking and distributed processing. This approach has an advantage that information collection and processing are placed closer to the sources of this information. The goals are to reduce traffic, latency, and to be robust against a lossy or failed Internet connection. We see management of IoT devices from the network configuration management perspective. This thesis proposes a framework for network configuration management of heterogeneous, constrained IoT devices by using semantic descriptions for interoperability. The MYNO framework is an acronym for MQTT, YANG, NETCONF and Ontology. The NETCONF protocol is the IETF standard for network configuration management. The MQTT protocol is the de-facto standard in the IoT. We picked up the idea of the NETCONF-MQTT bridge, originally proposed by Scheffler and Bonneß[2017], and extended it with semantic device descriptions. These device descriptions provide a description of the device capabilities. They are based on the oneM2M Base ontology and formalized by the Semantic Web Standards. The novel approach is using a ontology-based device description directly on a constrained device in combination with the MQTT protocol. The bridge was extended in order to query such descriptions. Using a semantic annotation, we achieved that the device capabilities are self-descriptive, machine readable and re-usable. The concept of a Virtual Device was introduced and implemented, based on semantic device descriptions. A Virtual Device aggregates the capabilities of all devices at the edge network and contributes therefore to the scalability. Thus, it is possible to control all devices via a single RPC call. The model-driven NETCONF Web-Client is generated automatically from this YANG model which is generated by the bridge based on the semantic device description. The Web-Client provides a user-friendly interface, offers RPC calls and displays sensor values. We demonstrate the feasibility of this approach in different use cases: sensor and actuator scenarios, as well as event configuration and triggering. The semantic approach results in increased memory overhead. Therefore, we evaluated CBOR and RDF HDT for optimization of ontology-based device descriptions for use on constrained devices. The evaluation shows that CBOR is not suitable for long strings and RDF HDT is a promising candidate but is still a W3C Member Submission. Finally, we used an optimized JSON-LD format for the syntax of the device descriptions. One of the security tasks of network management is the distribution of firmware updates. The MYNO Update Protocol (MUP) was developed and evaluated on constrained devices CC2538dk and 6LoWPAN. The MYNO update process is focused on freshness and authenticity of the firmware. The evaluation shows that it is challenging but feasible to bring the firmware updates to constrained devices using MQTT. As a new requirement for the next MQTT version, we propose to add a slicing feature for the better support of constrained devices. The MQTT broker should slice data to the maximum packet size specified by the device and transfer it slice-by-slice. For the performance and scalability evaluation of MYNO framework, we setup the High Precision Agriculture demonstrator with 10 ESP-32 NodeMCU boards at the edge of the network. The ESP-32 NodeMCU boards, connected by WLAN, were equipped with six sensors and two actuators. The performance evaluation shows that the processing of ontology-based descriptions on a Raspberry Pi 3B with the RDFLib is a challenging task regarding computational power. Nevertheless, it is feasible because it must be done only once per device during the discovery process. The MYNO framework was tested with heterogeneous devices such as CC2538dk from Texas Instruments, Arduino Y{\´u}n Rev 3, and ESP-32 NodeMCU, and IP-based networks such as 6LoWPAN and WLAN. Summarizing, with the MYNO framework we could show that the semantic approach on constrained devices is feasible in the IoT.}, language = {en} } @misc{SahlmannSchefflerSchnor2018, author = {Sahlmann, Kristina and Scheffler, Thomas and Schnor, Bettina}, title = {Ontology-driven Device Descriptions for IoT Network Management}, series = {2018 Global Internet of Things Summit (GIoTS)}, journal = {2018 Global Internet of Things Summit (GIoTS)}, publisher = {IEEE}, address = {New York}, isbn = {978-1-5386-6451-3}, doi = {10.1109/GIOTS.2018.8534569}, pages = {295 -- 300}, year = {2018}, abstract = {One particular challenge in the Internet of Things is the management of many heterogeneous things. The things are typically constrained devices with limited memory, power, network and processing capacity. Configuring every device manually is a tedious task. We propose an interoperable way to configure an IoT network automatically using existing standards. The proposed NETCONF-MQTT bridge intermediates between the constrained devices (speaking MQTT) and the network management standard NETCONF. The NETCONF-MQTT bridge generates dynamically YANG data models from the semantic description of the device capabilities based on the oneM2M ontology. We evaluate the approach for two use cases, i.e. describing an actuator and a sensor scenario.}, language = {en} }