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Cone-beam computed tomography (CBCT) in dental practice is becoming increasingly popular. However, the correct teeth identification, positioning and diagnosis based on CBCT can be tedious and challenging for the untrained eye. This is due to additional training, specific knowledge and time required for analysis and diagnosis. When compared to conventional dental imaging methods. In this study, we introduce a novel artificial intelligence (AI) system that facilitates analysis and diagnosis. This system is based on deep learning approaches that can localize teeth and define pathologies within three-dimensional CBCT scans. The study showed that the diagnostic performance of AI system image interpretation reaches and sometimes exceeds in comparison to clinician’s expertise. In this randomized cross-over trial we demonstrated a significant improvement of aided diagnostic accuracy for various dental diseases in comparison to a group of radiologists that made unaided decisions. AI can be used for both stand-alone CBCT interpretation and as a decision support system to improve quality of diagnostics and time efficiency.

Summary A lot of anomalies can occur and lead to failures during drilling process. It is crucial to detect these deviations from normal process as soon as possible, so engineers can analyse and decide what activities to take in order to prevent potential NPT. In this work we propose a new machine learning based approach for detection abnormal drilling behaviour in an online manner. The idea is to cluster drilling data, which is preprocessed in a very special way. Our aproach allows using all available data for training as it does not need any labeled data and incorporates both raw drilling parameters and expert knowledge, thus enhancing prediction results.

In this paper we present an enhanced and new optimization algorithm based on Particle Swarm Optimization (PSO) that can be used in reservoir characterization applications to determine multiple solutions that reproduce measurements within satisfactory accuracy. The method is illustrated on a history-matching problem where significant speed-up is obtained with respect to a standard PSO implementation. PSO is a global-search iterative technique where the solution space is explored using a swarm of particles. In every PSO iteration each particle is individually attracted to: the best point (in terms of objective function) in the swarm during last iteration, the best point visited by that particle in all iterations, and the best point found by any particle in all iterations. In the PSO variant proposed here, rather than single points, collections of points carefully selected are used as attractors. The algorithm ensures by a series of mechanisms that the number of attractors is adequate and that the solutions progressively determined are sufficiently different from one another. A series of experiments were performed with a synthetic model based on a real oil field for which nine years of historical data were generated. Both standard PSO and the PSO variant were tested to obtain several models that reproduced well rates within acceptable accuracy. In order to determine multiple solutions via standard PSO (which usually returns only one solution), a number of independent runs with different initial conditions were considered (i.e., standard PSO was run in multi-start fashion). In our experiments, which had a budget of 3,072 simulations in the two cases, the number of solutions found on average by standard PSO and by our PSO variant was 8 and 837, respectively. That is, multi-start standard PSO may require, on average, around 100 times more simulations than our PSO variant to compute a comparable number of models (possibly) distributed in similar manner in the solution space. These results may be explained by noticing that the search for multiple solutions may be more efficient when all information is considered simultaneously than separately by means of a number of independent runs. Standard PSO, when applied to many uncertainty quantification problems, may provide only one solution because the particles in the swarm generally tend to converge to essentially a single point. The Ensemble Kalman Filter (EnKF), which has lately become a very popular history-matching algorithm, presents a similar problem because the ensemble sometimes collapses into one solution. The PSO variant introduced in this work can be an efficient alternative to these algorithms in reservoir characterization since it has been designed to provide multiple and different solutions in a single run.

In the study there are introduced several control methods that maximize average velocity of the vibratory robot subject to several constraints. The robot is presented by a rigid box with a pendulum inside it. It can move forwards and backwards and there is a Coulomb friction between the box and the surface. In the paper it is not only shown the difference and advantages of proposed control laws but there is also done a comparison between efforts done by the motor that provides rotation of the pendulum for different control methods.

The subject of the study is control synthesis for a vibratory robot, which is presented by a rigid box with a pendulum inside it. The robot can move forward and backward and there is a Coulomb friction between the box and the surface. There are considered certain constraints of motion of the robot and limitations of control. In this paper, there is shown that the proposed control not only provides motion within the constraints and limitations but also maximizes average velocity of the robot. This control contains two phases on each period: resting phase where the box is standing still and gliding phase where the robot is moving forward. To show the advantages of the proposed solution there is provided numerical comparison between different types of control. Numerical experiments also show that the considered control appears to be energetically efficient.