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Operating criteria for power systems, such as theN−1-criterion, are often based on evaluating whether the system is vulnerable to a specific set of contingencies. Therefore, a major part of power system security is concerned with establishing regions in parameter space where the system is vulnerable to specific contingencies. In this article we exploit the possibility of using Monte Carlo simulati

Guaranteeing stability of control applications in embedded systems, or cyber-physical systems, is perhaps the alpha and omega of implementing such applications. However, as opposed to the classical real-time systems where often the acceptance criterion is meeting the deadline, control applications do not primarily enforce hard deadlines. In the case of control applications, stability is considered

The problem of modeling and controlling re- sources in a system with interaction between hardware and software is considered. A model encompassing both hardware and software dynamics is developed together with an on- line estimation scheme in order reduce dependence on a- priori information. A control structure is presented in order to control performance under constrained resource situations and

Grafchart is a graphical programming language for sequential control applications. It exists in two versions: the basic version (BV) and the high-level version (HLV). The currently used Grafchart tool, JGrafchart, only supports BV. To enable further research on HLV, it must be supported by JGrafchart. Since HLV is a superset of BV it is desirable to add it as an extension to the current implementa

The problem to minimize power losses in an electrical network subject to voltage and power constraints is in general hard to solve. However, it has recently been discovered that semidefinite programming relaxations in many cases enable exact computation of the global optimum. Here we point out a fundamental reason for the successful relaxations, namely that the passive network components give rise

Feature quantization is a crucial component for efficient large scale image retrieval and object recognition. By quantizing local features into visual words, one hopes that features that match each other obtain the same word ID. Then, similarities between images can be measured with respect to the corresponding histograms of visual words. Given the appearance variations of local features, traditio

This paper presents a combined experiment and identification procedure, well suited to obtain low-order dynamic models of a patients’ response to continuous drug administration. The experiment requires no a priori information and is of very short duration. The identification method provides both a parametric low-order model, and an estimate of the parameter error covariance. It has been demonstrat

Recent years’ progress in the development of Continuous Glucose Monitors (CGM) has made rich well-sampled glucose data readily available. Reliable, frequent measurements are of outmost importance for the emerging closed-loop control of diabetic plasma glucose. However, these sensors do not measure the variable of primary interest - plasma glucose, but a delayed signal - the interstitial glucose. T

We consider a wind power plant of megawatt wind turbines operating in derated mode. When operating in this mode, the wind power plant controller is free to distribute power set-points to the individual turbines, as long as the total power demand is met. In this work, we design a controller that exploits this freedom to reduce the fatigue on the turbines in the wind power plant. We show that the co

We define the notion of convex-monotone system and prove that for such systems the state trajectory x(⋅) is a convex function of the initial state x(0) and the input trajectory u(⋅). This observation gives a useful class of nonlinear dynamical systems for which control design can be performed by convex optimization. Applications to evolutionary dynamics of diseases and voltage stability in power n

This technical note investigates the model reduction problem for mean square stable discrete time Markov jump linear systems. For this class of systems a balanced truncation algorithm is developed. The reduced order model is suboptimal, however the approximation error, which is captured by means of the stochastic L2 gain, is bounded from above by twice the sum of singular numbers associated to the

Advances in Intelligent Transport Systems (ITS), intelligent vehicles and cooperative systems are enabling traffic and transport solutions that are both safer and more environmentally acceptable. While it is well known that high dependability is a desirable feature it has a price, and the level of dependability needed varies from application to application. Typical examples are cooperative safety

Three approaches of iterative learning control (ILC) applied to a Gantry-Tau parallel kinematic robot aC algorithms using 1) measured motor angles, 2) tool-position estimates, and for evaluation purposes, 3l position. The approaches are compared experimentally, with the tool performance evaluated using extert is concluded that the tool performance can be improved using tool-position estimates in t

In this paper an order reduction method for spatially distributed models is presented. Such systems may be modeled as two nodes interacting with each other through feedback. A model of one of the nodes reduced in such a way, that the closed loop performance is approximated. The method exploits a coprime factor description of the closed loop model and semidefinite programming. The method is related

Clock synchronization is a necessary component in modern distributed systems, especially WSN. Despite the great effort and the numerous improvements, the existing synchronization schemes do not yet address the cancellation of propagation delays. Up to a few years ago, this was not perceived as a problem, because the time-stamping precision was a more limiting factor for the accuracy achievable wit