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Nicola Bezzo – 1st expert on this subject based on the ideXlab platform
Fast Run-time Monitoring, Replanning, and Recovery for Safe autonomous system Operations2019 IEEE RSJ International Conference on Intelligent Robots and Systems (IROS), 2019Co-Authors: Nicola BezzoAbstract:
In this paper, we present a fast run-time monitoring framework for safety assurance during autonomous system operations in uncertain environments. Modern unmanned vehicles rely on periodic sensor measurements for motion planning and control. However, a vehicle may not always be able to obtain its state information due to various reasons such as sensor failures, signal occlusions, and communication problems. To guarantee the safety of a system during these circumstances under the presence of disturbance and noise, we propose a novel fast reachability analysis approach that leverages Gaussian process regression theory to predict future states of the system at run-time. We also propose a self/event-triggered monitoring and replanning approach which leverages our fast reachability scheme to recover the system when needed and replan its trajectory to guarantee safety constraints (i.e., the system will not collide with any obstacles). Our technique is validated both with simulations and experiments on unmanned aerial vehicles case studies in cluttered environments under the effect of unknown wind disturbance at run-time.
Zhao Jing – 2nd expert on this subject based on the ideXlab platform
The non-piecewise-linear autonomous system. II. The complex bifurcation structure38th Midwest Symposium on Circuits and Systems. Proceedings, 1995Co-Authors: Yu Zhiping, Zhao JingAbstract:
In the companion paper (see ibid., p. 612-15, Aug. 1995), we have presented novel time waveforms revealed in the non-piecewise-linear autonomous system (NPLAS) and have advanced a numerical symbol representation to analyze the complex waveforms. In this paper, we introduce definitions of the unit waveforms and the allotropic waveforms and characterize the bifurcation structure, of the system with further study of the complex periodic waveforms. In addition, we demonstrate the bifurcation regularity through the union of the sets and the Farey sum.
The non-piecewise-linear autonomous system. I. More details on the periodic waveforms38th Midwest Symposium on Circuits and Systems. Proceedings, 1995Co-Authors: Yu Zhiping, Zhao JingAbstract:
In the non-piecewise-linear autonomous system (NPLAS) a power avalanche transistor, whose curve measured in the I-V plane is not simply characterized by piecewise straight-line segments, is used for the nonlinear element. From the NPLAS, much more complicated and detailed bifurcation phenomena than that in other nonautonomous and autonomous systems have been observed. This paper presents quite a number of novel and complex waveform. In order to distinguish and investigate the complex waveforms a new numerical symbol representation is advanced.
Michael Howarth – 3rd expert on this subject based on the ideXlab platform
Joint optimization of intra- and inter-autonomous system traffic engineeringIEEE Transactions on Network and Service Management, 2009Co-Authors: Kin-hon Ho, George Pavlou, Ning Wang, Michael HowarthAbstract:
Traffic Engineering (TE) involves network configuration in order to achieve optimal IP network performance. The existing literature considers intra- and inter-AS (autonomous system) TE independently. However, if these two aspects are considered separately, the overall network performance may not be truly optimized. This is due to the interaction between intra and inter-AS TE, where a good solution of inter-AS TE may not be good for intra-AS TE. To remedy this situation, we propose a joint optimization of intra- and inter-AS TE in order to improve the overall network performance by simultaneously finding the best egress points for inter-AS traffic and the best routing scheme for intra-AS traffic. Three strategies are presented to attack the problem, sequential, nested and integrated optimization. Our evaluation shows that, in comparison to sequential and nested optimization, integrated optimization can significantly improve overall network performance by being able to accommodate approximately 30%-60% more traffic demand.
Joint Optimization of Intra- and Inter-autonomous system Traffic Engineering2006 IEEE IFIP Network Operations and Management Symposium NOMS 2006, 2006Co-Authors: Kin-hon Ho, Michael Howarth, George Pavlou, Ning Wang, S. GeorgoulasAbstract:
Traffic engineering (TE) is used to optimize IP operational network performance. The existing literature generally considers intra- and inter-AS (autonomous system) TE independently. However, the overall network performance may not be truly optimized when these aspects are considered separately. This is due to the interaction between intra- and inter-AS TE, where a solution of intra-AS TE may not be a good input to inter-AS TE and vice versa. To remedy this situation, we propose considering intra-AS aspects during inter-AS TE and vice versa. We propose a joint optimization of intra- and inter-AS TE to further improve the overall network performance by simultaneously finding the best egress points for the inter-AS traffic and the best routing scheme for the intra-AS traffic. Three strategies are presented to attack the problem, namely sequential, nested and integrated optimization. Our simulation study shows that, compared to sequential and nested optimization, integrated optimization can significantly improve the overall network performance by accommodating 30%-60% more traffic demands