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Tight human-robot interaction and collaboration will characterize future robot tasks. Robot working environments will be increasingly unstructured, as safety barriers will be removed to allow a continuous cooperation of robotic and human workers. Such a working scenario calls for novel safety systems capable of combining productivity with workers’ safety. In this paper, a method for the definition

In this paper we investigate a system for tracking the motion of box jellyfish tripedalia cystophora in a special test setup. The goal is to measure the motor response of the animal given certain visual stimuli. The approach is based on tracking the special sensory structures – the rhopalia – of the box jellyfish from high-speed video sequences. We have focused on a realtime system with simple bui

Time-triggered periodic control implementations are over provisioned for many execution scenarios in which the states of the controlled plants are close to equilibrium. To address this inefficient use of computation resources, researchers have proposed self-triggered control approaches in which the control task computes its execution deadline at runtime based on the state and dynamical properties

Quality requirements complement functional requirements with information on the target quality levels of software functions or emergent system quality aspects. In release planning the allocation of development effort in further investments into product enhancements, new or enhanced functions are competing with quality improvements for limited resources. When setting balanced quality targets for de

With larger penetrations of wind power, the uncertainty increases in power systems operations. The wind power forecast errors must be accounted for by adapting existing operating tools or designing new ones. A switch from the deterministic framework used today to a probabilistic one has been advocated. This two-part paper presents a framework for risk-based operations of power systems. This framew

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

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