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Background The application of safety principles from the aviation industry to the operating room has offered hope in reducing surgical complications. This study aimed to assess the impact on major surgical complications of adding an aviation-based team training programme after checklist implementation. Methods A prospective parallel-group cluster trial was undertaken between September 2011 and March 2013. Operating room teams from 31 hospitals were assigned randomly to participate in a team training programme focused on major concepts of crew resource management and checklist utilization. The primary outcome measure was the occurrence of any major adverse event, including death, during the hospital stay within the first 30 days after surgery. Using a difference-in-difference approach, the ratio of the odds ratios (ROR) was estimated to compare changes in surgical outcomes between intervention and control hospitals. Results Some 22 779 patients were enrolled, including 5934 before and 16 845 after team training implementation. The risk of major adverse events fell from 8·8 to 5·5 per cent in 16 intervention hospitals (adjusted odds ratio 0·57, 95 per cent c.i. 0·48 to 0·68; P < 0·001) and from 7·9 to 5·4 per cent in 15 control hospitals (odds ratio 0·64, 0·50 to 0·81; P < 0·001), resulting in the absence of difference between arms (ROR 0·90, 95 per cent c.i. 0·67 to 1·21; P = 0·474). Outcome trends revealed significant improvements among ten institutions, equally distributed across intervention and control hospitals. Conclusion Surgical outcomes improved substantially, with no difference between trial arms. Successful implementation of an aviation-based team training programme appears to require modification and adaptation of its principles in the context of the the surgical milieu. Registration number: NCT01384474 (http://www.clinicaltrials.gov).

This paper presents a simulation-based model for manual driving strategies that will minimize energy consumption for high-speed trains. Specific characteristics of both high-speed lines (HSLs) and manual driving strategies are considered in order to obtain achievable designs that can be tested on commercial services. The proposed design model calculates a list of efficient high-level commands to be systematically executed by the driver on an HSL along the trip. The design is based on a detailed simulation model of the train's motion (taking into account track and train characteristics and operational constraints), combined with a genetic algorithm to select the best driving. Continuous control solution by mathematical optimization is avoided, as it is not an appropriate reference for manual driving in HSL. The validation of the simulation model is focused on running resistance, tractive/braking efficiencies, and consumption of auxiliary equipment, and shows differences between real measurements and simulated results which are lower than 2% both in run time and energy consumption. Finally, a real case is presented in which the proposed model was used to design efficient driving strategies that were subsequently implemented on commercial services along the Spanish HSL Madrid–Barcelona in both directions, measuring average energy savings of 23 and 18%, respectively, when the efficient driving strategies were compared with measured standard manual driving. The future scope will be the application of this model to online recalculation of driving commands. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Resume Les lesions hemispheriques droites (LHD) sont classiquement connues pour s'accompagner de troubles somatognosiques (TS) — souvent designes comme troubles du schema corporel (TSC) — unilateraux gauches. Ces TSC ≪classiques≫ sont en regle transitoires et ne peuvent expliquer les difficultes particulieres de la reeducation motrice des hemiplegies gauches. Ce travail preliminaire a pour objectifs: de rechercher l'existence de TS apres disparition d'eventuels TSC ≪classiques≫ initiaux; de verifier leur nature cognitive; de preciser le niveau du trouble en reference aux donnees recentes sur le schema corporel postural (SCP) et sur l'influence de l'heminegligence sur la proprioception. Neuf patients en reeducation pour hemiplegie gauche par AVC hemispherique droit unique et dix temoins apparies pour l'âge ont ete soumis a une batterie de tests d'imitation de postures et de mouvements. Les resultats font apparaitre une difference significative entre patients et temoins ( p ). Les causes d'echec sont un deficit sensitif important et la complexite des postures. Ces resultats s'accordent avec l'existence d'authentiques TS, pouvant concerner les deux hemicorps et qui ne seraient pas a proprement parler des TSC mais un deficit d'utilisation du SCP. Trois niveaux de traitement des informations d'origine proprioceptive sont envisages: niveau sensoriel elementaire, niveau perceptif, niveau constructif. Les implications pratiques sont discutees.

This article presents a combined simulation and optimisation technique to optimise the energy consumption of a single manual-driving train service with inter-stations along a High Speed Line. For this purpose, the best energy efficient driving strategies along every stretch between two stations will be simulated with an accurate and detailed train simulator to obtain the run time and energy consumption Pareto curves of each stretch. Afterwards, an optimisation tool will distribute the available slack time for the service among the stretches, which will minimise the overall energy consumption of the service. The potential of the method will be shown with a case study at the end of the article.

This paper presents a new algorithm and a procedure for the efficient and accurate calculation of braking distances satisfying current safety Standards. One of these Standards is applied in ADIF (Spanish Railway Infrastructure Administrator), for instance, in the design of signaling systems, to locate signals and balises. Following the Standard, braking distance tables depend on the average gradient along that distance and the speed reduction. In practice, an initial slope is calculated over a forecasted braking distance along the railway track, so that if the corresponding braking distance given by the Standard highly differs from the initial one, it will be necessary to recalculate the average gradient and apply the Standard again. The manual application of this process may end up overestimating braking distances unnecessarily (as the Standard itself includes safety coefficients), falling into additional signaling costs and reducing the line capacity. This paper presents an iterative calculation procedure to adjust as much as possible the distance required by the Standard, so that the average gradient introduced into the Standard corresponds precisely with the braking distance where the average gradient has been computed. Furthermore, the algorithm improves the accuracy of the average gradient calculation, considering the slope transition curves instead of sharp slope vertices. The proposed algorithm has been implemented in a computer tool for its use in railway lines operated by ADIF, according to the braking distance current Standard (N.T.C.020.95). This tool incorporates a railways net model that allows the user to introduce a final braking point, a speed reduction, and provides automatically the kilometric line point where the brake should start. In addition, this tool provides a systematic procedure to obtain braking distances in the different technical departments of ADIF. This paper compares, in real cases, the non-assisted previous procedure with the application of the proposed one, showing the refined braking distances.

Summary form only given as follows. During power restoration, the energization of a no load transformer can lead to high overvoltages, the amplitude being sensible to initial conditions. This document describes an approach based on the AUTO program, which is a complementary tool to EMTP, and may help the understanding of the behaviour of the electrical circuit. The case of a progressive energization of a transformer is described, with a progressive energization from the hydraulic power plant of Pied de Borne towards the thermal power plant of Tricastin. Tests have been performed by the Exploitation Department, with a progressive voltage rise, the network having a resonant frequency at 164 Hz, with a distortion of the voltage above 0.6 Un, and the presence of the third harmonic, the maximum being obtained after ten seconds. A single phase of the network has been used and equations of this network have been solved with the AUTO program, showing that the network can generate the third harmonic, depending also on the value of the flux in the network, the third harmonic being reached for a value of 0.65 kWh; it has also been validated by EMTP calculations. A time domain approach, with programs like EMTP is however necessary to calculate the maximum overvoltage in a three phase network, especially when the phase to phase insulation of the equipment is concerned. In the case of high overvoltages, palliative solutions can be suggested like synchronizing devices in circuit-breakers, circuit-breakers with resistances and zinc-oxide arresters.

This paper describes a method for the modeling of the energization of power transformers taking into account the data accuracy (line capacitances, subtransient reactance of the generator, air core reactance of the target transformer) which has a strong impact on the resonance frequency of the network and also on the temporary harmonic overvoltages and currents involved. The influence on the results of the studies is described. Those parameters have been assessed inside their accuracy boundaries from on site measurements on a real network; in the case of the generator, the value derived from tests has been confirmed by 3D field programs. In the cases where little information is given by the manufacturers, the sensitivity to parameters has to be taken into account in order not to underestimate the overvoltages, and to determine the best palliative solutions in order to energize the transformers in good conditions.