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Auflistung nach Schlagwort "Performance evaluation"

1 - 3 von 3
  • Zeitschriftenartikel
    Development, Control, and Empirical Evaluation of the Six-Legged Robot SpaceClimber Designed for Extraterrestrial Crater Exploration
    (KI - Künstliche Intelligenz: Vol. 28, No. 2, 2014) Bartsch, Sebastian
    In the recent past, mobile robots played an important role in the field of extraterrestrial surface exploration. Unfortunately, the currently available space exploration rovers do not provide the necessary mobility to reach scientifically interesting places in rough and steep terrain like boulder fields and craters. Multi-legged robots have proven to be a good solution to provide high mobility in unstructured environments. However, space missions place high demands on the system design, control, and performance which are hard to fulfill with such kinematically complex systems. My dissertation focuses on the development, control, and evaluation of a six-legged robot for the purpose of lunar crater exploration considering the requirements arising from the envisaged mission scenario. The performance of the developed system is evaluated and optimized based on empirical data acquired in significant and reproducible experiments performed in a laboratory environment in order to show the capability of the system to perform such a task and to provide a basis for the comparability with other mobile robotic solutions.
  • Konferenzbeitrag
    Dynamic Updates of Virtual PLCs deployed as Kubernetes Microservices
    (Software Engineering 2022, 2022) Koziolek, Heiko; Burger, Andreas
    Industrial control systems (e.g. programmable logic control\-lers, PLC or distributed control systems, DCS) cyclically execute control algorithms to automated production processes. Nowadays, for many applications their deployment is moving from dedicated embedded controllers into more flexible container environments, thus becoming ''Virtual PLCs''. It is difficult to update such containerized Virtual PLCs during runtime by switching to a newer instance, which requires transferring internal state. Former research has only proposed dynamic update approaches for single embedded controllers, while other work introduced special Kubernetes (K8s) state replication approaches, which did not support cyclic real-time applications. We propose a dynamic update mechanism for Virtual PLCs deployed as K8s microservices. This approach is based on a purpose-built K8s Operator and allows control application updates without halting the production processes. Our experimental validation shows that the approach can support the internal state transfer of large industrial control applications (100.000 state variables) within only 15 percent of the available cycle slack time. Therefore, the approach creates vast opportunities for updating applications on-the-fly and migrating them between nodes in a cloud-native fashion.
  • Zeitschriftenartikel
    Vom Performance Tuning zum Software Performance Engineering am Beispiel datenbankbasierter Anwendungssysteme Reduktion des performancebedingten Entwicklungsrisikos
    (Informatik-Spektrum: Vol. 22, No. 4, 1999) Rautenstrauch, Claus; Scholz, André
    Während es für das Tuning der physischen Datenbank eine Vielzahl von systemabhängigen Methoden gibt, ist die systematische und damit auch herstellerneutrale Performance-Steuerung von datenbankbasierten Anwendungssystemen bisher nur unzureichend beachtet worden. In diesem Beitrag werden zwei grundsätzlich verschiedene Strategien zur Lösung dieses Problems in ihrer Systematik aufgezeigt und deren Integrationsmöglichkeiten erläutert. Zum einem wird dazu der heute weit verbreitete, ex-post-basierte Ansatz des Performance-Tunings dargestellt und in einem Modell systematisiert. Zum anderen wird in Abgrenzung davon das integrierbare a priori-Modell Software Performance Engineering vorgestellt, für dessen betriebliche Umsetzung ein Referenzvorgehensmodell beschrieben wird.AbstractAs there are a lot of system dependent methods for physical tuning of a database, up to now, systematic procedures to increase the performance of database applications are quite rare. Two different strategies are discussed in this paper to solve this problem. On the one hand a systematic approach for the tuning procedure is described. On the other hand we present a reference process model supporting the forward-oriented software performance engineering approach.