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An efficient organocatalytic asymmetric synthesis of α-hydroxyketones has been developed. Quinine-derived thiourea catalyzed the enantioselective Friedel-Crafts alkylation of naphthols and activated phenols with aryl- and alkylglyoxal hydrates, providing the corresponding chiral α-hydroxyketones with high yields (up to 97%) and excellent enantioselectivities (up to 99% ee).

In this work, a novel algorithm for trajectory tracking in mobile robots is presented. For the purpose of tracking trajectory, a methodology based on the interpolation of trigonometric functions of the wheeled mobile robot kinematics is proposed. In addition, the convergence of the interpolation-based control systems is analysed. Furthermore, the optimal controller parameters are selected through Monte Carlo Experiments (MCE) in order to minimize a cost index. The MCE is able to find, the best set of gains that minimizes the tracking error. Experimental results over a mobile robot Pionner 3AT are conclusive and satisfactory. In addition, a comparative study of control performance is carried out against another controllers.

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Stand-alone and networked surgical simulators based on virtual reality have been proposed as a means to train surgeons in specific surgical skills with or without expert guidance and supervision. However, a surgical operation usually involves a group of medical practitioners who cooperate as team members. To this end, CNVSS have been proposed for the collaborative training of surgical procedures in which users with different surgical roles can take part in the training session. To be successful, these simulators should guarantee synchronicity, which requires (1) consistent viewing of the surgical scene and (2) a quick response time. These two variables are affected by factors such as users' machine capabilities and network conditions. As far as we know, the impact of these factors on the performance of CNVSS has not been evaluated. In this paper, we describe the development of CNVSS and a statistical factorial design of experiments (DOE) to determine the most important factors affecting collaboration in CNVSS. From the results obtained, it was concluded that delay, jitter, packet loss percentage, and processor speed have a major impact on collaboration in CNVSS.