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A quench protection concept based on coupled secondary coils is studied for inductively transferring energy out of a quenching superconducting dipole and thus limiting the peak hotspot temperature. So-called 'quench absorption coils' are placed in close proximity to the superconducting coils and are connected in series with a diode for the purpose of preventing current transformation during regular operation. During a quench, current is then transformed into the quench absorption coils so that a significant fraction of the stored magnetic energy is dissipated in the these coils. Numerical calculations are performed to determine the impact of such a concept and to evaluate the dimensions of the quench absorption coils needed to obtain significant benefits. A previously constructed 15 T Nb3Sn block coil is taken as a reference layout. Finite-element calculations are used to determine the combined inductive and thermal response of this system and these calculations are validated with a numerical model using an adiabatic approximation. The calculation results indicate that during a quench the presence of the quench absorption coils reduces the energy dissipated in the superconducting coils by 45% and reduces the hotspot temperature by over 100 K. In addition, the peak resistive voltage over the superconducting coils is significantly reduced. This suggests that this concept may prove useful for magnet designs in which the hotspot temperature is a design driver. acceptedVersion

Within the future circular collider study, a 100-km long circular hadron collider is being designed for 100 TeV center-of-mass collision energies. The design of the 16 T Nb3Sn bending dipole magnets is carried out within the EuroCirCol collaboration. Three different type of dipole designs have been developed, each aiming to be as compact as possible, accounting for the design criteria. Quench protection a critical aspect of the magnet design and potentially limits the magnet compactness. The EuroCirCol magnets were designed assuming a protection system with significantly improved efficiency compared to the present LHC dipole protection. In this paper, we consider present state-of-the-art quench protection technologies, such as quench heaters and CLIQ, and apply them into the designed 16 T Block-type dipole. Two different simulation models are used to estimate the magnet hotspot temperature and voltages after a quench and consequently estimate the suitability of the different methods. acceptedVersion

In this paper, we propose a low complexity method for detection and tracking of potholes in video sequences taken by a camera placed inside a moving car. The region of interest for the detection of the potholes is selected as the image area where the road is observed with the highest resolution. A threshold-based algorithm generates a set of candidate regions. For each region the following features are extracted: its size, the regularity of the intensity surface, contrast with respect to background model, and the region's contour length and shape. The candidate regions are labeled as putative potholes by a decision tree according to these features, eliminating the false positives due to shadows of wayside objects. The putative potholes that are successfully tracked in consecutive frames are finally declared potholes. Experimental results with real video sequences show a good detection precision. acceptedVersion