A situation-aware task model for adaptive real-time systems
- PDF / 1,582,421 Bytes
- 11 Pages / 595.276 x 790.866 pts Page_size
- 24 Downloads / 170 Views
ORIGINAL RESEARCH
A situation‑aware task model for adaptive real‑time systems Nayreet Islam1 · Akramul Azim1 Received: 1 June 2019 / Accepted: 7 January 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Real-time systems are usually well-defined and operate based on a specific task model defined during system design. However, the system can interact with different objects from its environment at runtime and needs to guarantee its operational as well as timing behavior even in adverse environmental situations. Uncertainties in the system environment impose challenges on assuring the runtime behavior during system design. The system needs to adapt to different environmental situations which require the task model to consider the execution of adaptive tasks which can be activated in response to environmental events. We present an operational environment model that characterizes environmental situations of the real-time system and identifies the adaptive tasks needed to be activated at runtime. The adaptive tasks can be included and executed using a number of existing task models which allow non-deterministic task activation patterns. We present a situation-aware task model which efficiently maps the environmental events to (reduced) adaptive tasks. To demonstrate the applicability and usability of the proposed situation-aware task model, we perform the experimental analysis using two case studies: an automotive situation-aware task model, and an unmanned aerial vehicle situation-aware task model. The experimental results of our work show that the constructed situation-aware task model contains a maximum of nine vertices and 68 edges, provides an improvement in terms of scheduling overhead and in adaptation time (with respect to the considered existing task models). Keywords Situation-awareness · Environmental situations · Task models · Real-time systems · Adaptive systems
1 Introduction Nowadays, the real-time system (RTS) needs to facilitate adaptability for ensuring functional and timing requirements in different environmental situations. Ensuring functional and timing requirements at runtime, in our work, can be defined as the execution of a set of tasks which allow the RTS to handle a particular environmental situation without violating any timing constraints. Therefore, apart from the tasks whose order is defined by a particular scheduler during system design, an RTS needs to adapt to any changes in its environment by activating additional tasks at runtime. Designing and testing during the development stage can ensure the functional and timing requirements of the RTS which require an operational environment model to * Akramul Azim [email protected] Nayreet Islam [email protected] 1
Department of Electrical, Computer and Software Engineering, Ontario Tech University, Oshawa, Canada
characterize the adaptation requirements in different environmental situations (Cheng et al. 2014). An operational environment model of the RTS is useful for characterizing and validati
Data Loading...
