Publikationen

2020

• Determining the Load Inertia Contribution from Different Power Consumer Groups

  Thiesen, H. ., & Jauch, C. . (2020). Determining the Load Inertia Contribution from Different Power Consumer Groups. Energies, 13(7). http://doi.org/10.3390/en13071588 (Original work published April 2020)

  Abstract

  anzeigen ▸

  Power system inertia is a vital part of power system stability. The inertia response within the first seconds after a power imbalance reduces the velocity of which the grid frequency changes. At present, large shares of power system inertia are provided by synchronously rotating masses of conventional power plants. A minor part of power system inertia is supplied by power consumers. The energy system transformation results in an overall decreasing amount of power system inertia. Hence, inertia has to be provided synthetically in future power systems. In depth knowledge about the amount of inertia provided by power consumers is very important for a future application of units supplying synthetic inertia. It strongly promotes the technical efficiency and cost effective application. A blackout in the city of Flensburg allows for a detailed research on the inertia contribution from power consumers. Therefore, power consumer categories are introduced and the inertia contribution is calculated for each category. Overall, the inertia constant for different power consumers is in the range of 0.09 to 4.24 s if inertia constant calculations are based on the power demand. If inertia constant calculations are based on the apparent generator power, the load inertia constant is in the range of 0.01 to 0.19 s.

  • Suche auf Google Scholar
  • DOI Verweis

  Exportformate

  • BibTeX
  • EndNote X3 XML
  • EndNote 7 XML
  • EndNote tagged
  • RIS

  Weiterführende Links

  anzeigen ▸

  • Personenseiten

    • Thiesen, Henning
    • Jauch, Clemens

  • Abteilung/Einrichtung

    • Wind Energy Technology Institute

  Filter Tags

  • 2020
  • Journal Article
  • • Henning Thiesen
    • Prof. Dr. Clemens Jauch

• Simulation of scattered radiation during intraoperative imaging in a virtual reality learning environment

  Süncksen, M. ., Bott, O. ., Dresing, K. ., & Teistler, M. . (2020). Simulation of scattered radiation during intraoperative imaging in a virtual reality learning environment. International Journal of Computer Assisted Radiology and Surgery , 15, 691–701. http://doi.org/10.1007/s11548-020-02126-x (Original work published April 2020)

  Abstract

  anzeigen ▸

  Purpose Scattered radiation, which occurs when using a C-arm for intraoperative radiography, can be better understood through interactive visualization. We developed a virtual reality (VR) approach for the simulation of scattered radiation (SSR) as part of a C-arm training system. In VR, it is important to avoid cyber sickness, which is often caused by increased latency between head motion and image presentation inside the head-mounted display. As the latency requirement interferes with the computational complexity of the SSR, the goal has been to maintain a low latency during the simultaneous computation of the SSR on moderate-cost consumer hardware. Methods For use with a VR C-arm simulator, a CUDA-based Monte Carlo SSR has been improved to utilize GPU resources unused by the VR image generation. Resulting SSR data are visualized through volume rendering with pseudo-colored scattered radiation superimposed onto the virtual operating room. The resulting interactive VR–SSR environment was evaluated with operating room personnel (ORP) and surgeons using questionnaires. Results Depending on the imaged body part and computation parameters, the required computation time to complete one SSR run was between 1.6 and 4.2 s (ankle) and between 7.9 and 14.9 s (thigh), and VR frame times from 11 to 12 ms (95th percentile). The system was evaluated with ORP (n = 46) and surgeons (n = 25). The median of professional C-arm experience was 5 (range 1 to 34) years (ORP) and 12.5 (range 2 to 48) years (surgeons), respectively. The demonstrated prototype was found useful by 78% of ORP and 88% of the surgeons. On a Likert scale, more than 90% of both groups “agreed fully” that the presented way of visualizing SSR in VR helps understanding intraoperative exposure to scattered radiation. Conclusions Leveraging off-the-shelf computer equipment, the feasibility of SSR and VR for interactive training has been demonstrated. Evaluation participants showed a high interest for the presented approach. Feedback suggests that the visualization experienced by the users helps understanding radiation hazards in the operating room.

  • Suche auf Google Scholar
  • DOI Verweis

  Exportformate

  • BibTeX
  • EndNote X3 XML
  • EndNote 7 XML
  • EndNote tagged
  • RIS

  Weiterführende Links

  anzeigen ▸

  • Personenseiten

    • Teistler, Michael

  • Forschungsprojekt

    • Computerbasierte Ausbildung in der Medizinischen Bildgebung durch virtuelle und spielbasierte Lernumgebungen

  • Abteilung/Einrichtung

    • CIVU – Center for Interaction, Visualization and Usability

  • Profilbereich

    • Informatik und Gestaltung

  • Forschungsfeld

    • Digitalisierung im Gesundheitswesen
    • Human-Computer-Interaction

  • Fachbereich

    • Fachbereich 3: Information und Kommunikation

  Filter Tags

  • 2020
  • Journal Article
  • • Matthias Süncksen
    • Oliver Bott
    • Klaus Dresing
    • Michael Teistler

• Not up to Standard! Creating a Global Assessment Framework and Universal Proficiency Test for Maritime English.

  Noble, A. ., Van Son, L. ., & John, P. . (2020). Not up to Standard! Creating a Global Assessment Framework and Universal Proficiency Test for Maritime English. In Strategies and Analyses of Language and Communication in Multilingual and International Contexts (S. 10). Cambridge (UK): Cambridge Scholars Publishing. Abgerufen von https://www.cambridgescholars.com/product/978-1-5275-4324-9 (Original work published Februar 2020)

  • Suche auf Google Scholar

  Exportformate

  • BibTeX
  • EndNote X3 XML
  • EndNote 7 XML
  • EndNote tagged
  • RIS

  Weiterführende Links

  anzeigen ▸

  • Personenseiten

    • John, Peter

  • Fachbereich

    • Fachbereich 3: Information und Kommunikation

  Filter Tags

  • 2020
  • Book Chapter
  • • Alison Noble
    • Ludwina Van Son
    • Peter John

• Managing unreliability in automotive supply networks – an extension of the joint economic lot size model

  Gruchmann, T. ., & Brandenburg, M. . (2020). Managing unreliability in automotive supply networks – an extension of the joint economic lot size model. International Journal of Operational Research, 39(1). http://doi.org/10.1504/IJOR.2020.108838

  Abstract

  anzeigen ▸

  Within assembly network supply chains, supply disruptions can occur on every supplier-buyer link. Managing this network unreliability can help to reduce schedule instability and increases the overall efficiency of the supply chain accordingly. In this line, a stylised assembly network supply chain model is proposed with two suppliers and a single buyer using the joint economic lot sizing approach. This supply network can be disrupted by a shortage occurring at one of the two suppliers due to random machine breakdowns, which consequently creates dependent requirements variations affecting both the buyer and the entire network. First, the basic joint economic lot sizing model is extended by the said schedule instability. Second, a solution approach is presented concerning the determination of optimal lot sizes, the investment into the reliability of the supply network as well as the determination of safety stocks. Furthermore, the sensitivity of relevant model parameters is investigated by means of a numerical example. Managerial implications are accordingly derived focusing on the reliability of the supply network members and internal incentive structures.

  • Suche auf Google Scholar
  • DOI Verweis

  Exportformate

  • BibTeX
  • EndNote X3 XML
  • EndNote 7 XML
  • EndNote tagged
  • RIS

  Weiterführende Links

  anzeigen ▸

  • Personenseiten

    • Brandenburg, Marcus

  • Fachbereich

    • Fachbereich 4: Wirtschaft

  Filter Tags

  • 2020
  • Journal Article
  • • Tim Gruchmann
    • Marcus Brandenburg
  • • Schedule instability
    • Automotive supply networks
    • Joint economic lot sizing
    • Supply unreliability
    • Safety stocks

• Rapid Metabolome and Bioactivity Profiling of Fungi Associated with the Leaf and Rhizosphere of the Baltic Seagrass Zostera marina

  Petersen, L.-E. ., Marner, M. ., Labes, A. ., & Tasdemir, D. . (2020). Rapid Metabolome and Bioactivity Profiling of Fungi Associated with the Leaf and Rhizosphere of the Baltic Seagrass Zostera marina, Online-Ressource. http://doi.org/10.3390/md17070419

  • Suche auf Google Scholar
  • DOI Verweis

  Exportformate

  • BibTeX
  • EndNote X3 XML
  • EndNote 7 XML
  • EndNote tagged
  • RIS

  Filter Tags

  • 2020
  • Journal Article
  • • Lars-Erik Petersen
    • Michael Marner
    • Antje Labes
    • Deniz Tasdemir

• Construction of arithmetic secret sharing schemes by using torsion limits

  Tutdere, S. ., & Uzunkol, O. . (2020). Construction of arithmetic secret sharing schemes by using torsion limits. Hacettepe Journal of Mathematics and Statistics, 49, 638–647. http://doi.org/10.15672/hujms.460348

  • Suche auf Google Scholar
  • DOI Verweis

  Exportformate

  • BibTeX
  • EndNote X3 XML
  • EndNote 7 XML
  • EndNote tagged
  • RIS

  Weiterführende Links

  anzeigen ▸

  • Personenseiten

    • Uzunkol, Osmanbey

  • Fachbereich

    • Fachbereich 3: Information und Kommunikation

  Filter Tags

  • 2020
  • Journal Article
  • • Seher Tutdere
    • Osmanbey Uzunkol

• Implementing a Library for Probabilistic Programming Using Non-Strict Non-Determinism

  Dylus, S. ., Christiansen, J. ., & Teegen, F. . (2020). Implementing a Library for Probabilistic Programming Using Non-Strict Non-Determinism. Theory and Practice of Logic Programming, 20, 147–175. http://doi.org/10.1017/S1471068419000085

  • Suche auf Google Scholar
  • DOI Verweis

  Exportformate

  • BibTeX
  • EndNote X3 XML
  • EndNote 7 XML
  • EndNote tagged
  • RIS

  Weiterführende Links

  anzeigen ▸

  • Personenseiten

    • Christiansen, Jan

  • Fachbereich

    • Fachbereich 3: Information und Kommunikation

  Filter Tags

  • 2020
  • Journal Article
  • • Sandra Dylus
    • Jan Christiansen
    • Finn Teegen

• Comparing Eye Movements Between Physical Rotation Interaction Techniques

  Bertel, S. ., & Wetzel, S. . (2020). Comparing Eye Movements Between Physical Rotation Interaction Techniques. In ACM Symposium on Eye Tracking Research and Applications. New York, NY, USA: Association for Computing Machinery. http://doi.org/10.1145/3379156.3391355

  Abstract

  anzeigen ▸

  Recent studies have shown a number of procedural similarities between solving problems in mental and in physical rotation. Such similarities open up the interesting option to study mental rotation indirectly through physical rotation, with the advantage that physical rotation processes can be much more easily observed than mental ones. To better assess where solution processes in mental and physical rotation differ, though, it is important to know what influence any specific interaction method in physical rotation will have. We present results from a comparison of two such interaction methods: a one-handed, touch-based and a two-handed, ball-based method. Our analysis focuses on fixation durations and saccade amplitudes as proxies for mental load. Results show, importantly, that the choice of interaction method seems to matter but little. We therefore suggest that the existing findings of past studies that have compared mental to physical rotation are likely highly comparable, despite the fact that different interaction techniques were used.

  • Suche auf Google Scholar
  • DOI Verweis

  Exportformate

  • BibTeX
  • EndNote X3 XML
  • EndNote 7 XML
  • EndNote tagged
  • RIS

  Weiterführende Links

  anzeigen ▸

  • Personenseiten

    • Bertel, Sven

  • Abteilung/Einrichtung

    • CIVU – Center for Interaction, Visualization and Usability

  • Fachbereich

    • Fachbereich 3: Information und Kommunikation

  Filter Tags

  • 2020
  • Conference Paper
  • • Sven Bertel
    • Stefanie Wetzel
  • • physical rotation
    • fixation duration
    • saccade amplitude
    • mental rotation

• Rechnernetze: Ein einführendes Lehrbuch

  Riggert, W. ., & Lübben, R. . (2020). Rechnernetze: Ein einführendes Lehrbuch. Carl Hanser Verlag GmbH \& Company KG. http://doi.org/10.3139/9783446463691

  • Suche auf Google Scholar
  • DOI Verweis

  Exportformate

  • BibTeX
  • EndNote X3 XML
  • EndNote 7 XML
  • EndNote tagged
  • RIS

  Weiterführende Links

  anzeigen ▸

  • Personenseiten

    • Lübben, Ralf

  • Fachbereich

    • Fachbereich 4: Wirtschaft

  Filter Tags

  • 2020
  • Book
  • • Wolfgang Riggert
    • Ralf Lübben

• Untersuchung von opensource Datenbanksystemen auf Härtungsmaßnahmen unter Betrachtung des BSI IT-Grundschutz-Kompendium

  Bendig, H. . (2020). Untersuchung von opensource Datenbanksystemen auf Härtungsmaßnahmen unter Betrachtung des BSI IT-Grundschutz-Kompendium. Wismar University of Applied Sciences. Abgerufen von https://it-forensik.fiw.hs-wismar.de/index.php/Henner_Bendig

  Abstract

  anzeigen ▸

  Die Relevanz von Opensource Software (OSS) steigt immer weiter an. Laut einer Studie der Bitkom setzen heutzutage 69% aller Unternehmen, bewusst OSS ein und bis zu 75% der Unternehmen planen OSS einzusetzen [1]. Gleichzeitig steigt die Gefahr von Angriffen auf moderne Technologien [2]. Datenbanksysteme (DBS) stehen heute schon auf Platz 4 der am häufigsten angegriffenen IT-Systeme [3]. Die Wichtigkeit von Daten im heutigen Zeitalter steigt noch immer weiter man, somit ist eine noch höhere Angriffswahrscheinlichkeit auf DBS wahrscheinlich. In dieser Arbeit wurde die Umsetzbarkeit des Bausteins „APP.4.3 – Relationale Datenbanken“ des IT-Grundschutzkompendium der Bundesagentur für Sicherheit in der Informationstechnik (BSI) in den Opensource DBS Oracle MySQL, PostgreSQL und MongoDB untersucht. Die drei gewählten Systeme sind die derzeit am meist verbreiteten Opensource Datenbanksysteme und bedürfen daher erhöhte Aufmerksamkeit [4] [5]. Organisatorische Maßnahmen wurden anhand von Empfehlungen, Vorgaben und Beispielen erarbeitet. Technische Maßnahmen wurden nach Möglichkeit direkt in den DBS umgesetzt. Sofern keine interne Umsetzung notwendig war, wurden Opensource Erweiterungen von Drittanbietern gesucht und getestet. Anhand der vom BSI bereitgestellten Auditorencheckliste wurden die Maßnahmen bewertet. Organisatorische Maßnahmen wurden aus der Wertung herausgenommen. Es wurden die Punktekategorien 0 für gar nicht umsetzbar, 1 für teilweise umsetzbar und 2 für komplett umsetzbar vergeben. MySQL erreichte 73% der möglichen Punkte, PostgreSQL 67% und MongoDB 47%. Ein Großteil der notwendigen Funktionen wird vom Originalhersteller zwar bereitgestellt aber ist nur in der kommerziell verfügbaren Variante der Systeme aktivierbar. Abstract: The relevance of Open Source Software (OSS) is constantly increasing. According to a study by Bitkom, 69% of all companies today use OSS consciously and up to 75% of companies plan to use OSS [1]. At the same time the danger of attacks on modern technologies is increasing [2]. Database systems (DBS) are already in 4th place among the most frequently attacked IT systems [3]. The importance of data in today s age is still increasing, so an even higher probability of attack on DBS is likely. In this thesis the feasibility of the module ‚APP.4.3 - Relational Databases‘ of the IT basic protection compendium of the German Federal Agency for Information Security (BSI) was examined in the open source DBS Oracle MySQL, PostgreSQL and MongoDB. The three chosen systems are currently the most widespread open source database systems and therefore require special attention [4] [5]. Organisational requirements were developed on the basis of recommendations, specifications and examples. Where possible, technical requirements were implemented directly in the DBS. As far as no internal implementation was possible, open source extensions of third-party providers were searched and tested. The requirements were evaluated using the auditor checklist provided by the BSI. Organizational requirements were removed from the evaluation. The point categories 0 for not realizable at all, 1 for partially realizable and 2 for completely realizable were assigned. MySQL achieved 73% of the possible points, PostgreSQL 67% and MongoDB 47%. Most of the required functions are provided by the original manufacturer but can only be activated in the commercially available version of the systems.

  • Suche auf Google Scholar

  Exportformate

  • BibTeX
  • EndNote X3 XML
  • EndNote 7 XML
  • EndNote tagged
  • RIS

  Weiterführende Links

  anzeigen ▸

  • Personenseiten

    • Bendig, Henner

  • Forschungsfeld

    • IT-Security

  Filter Tags

  • 2020
  • Miscellaneous
  • • Henner Bendig