In this paper a four floor elevator system as platform for Mechatronics engineering education is presented. The elevator system is proposed as a device to support undergraduate and postgraduate ...courses such as: dynamic analysis, control engineering, sensors and actuators, and programmable logic controllers. A Proportional Derivative (PD) type controller with trajectory tracking is proposed to carry the passengers (load) between the different floors. Then an algebraic identifier is used to estimate the mass in the elevator car (cabin) that can be applied online to avoid parametric uncertainty in the PD type controller and improve the performance in trajectory tracking task. Also, as an alternative solution, a robust GPI controller is proposed for better performance and minimize the tracking error using only cabin position measurements. Some simulation results are included using an elevator system virtual prototype in MSC Adams View® in co-simulation with Simulink- Matlab®, to illustrate the performance of the algebraic identifier and the controllers proposed.
The follow-up of HBV markers in selected high infection risk populations, in patients from the hemodialysis and peritoneal dialysis services was used to assess the effectiveness of a special ...vaccination program. Viral infection markers were studied in prevalence cross sections of the whole population of patients, and also by recording the reports of clinical cases of hepatitis B occurred during that period in those groups of patients. The prevention program consisted of the vaccination of all patients negative to the viral markers and the indication of vaccination for the new cases during the period of the kidney disease, just before the start of the treatment at the hemodialysis unit; besides all the persons susceptible to infection that had already been included in the program, regardless of the stage of the disease. The results show the benefit of the vaccination in these patients, but it is more effective in the period before the treatment with dialysis where there is a lower possibility of being exposed to the virus and the immune system is still competent. Once the program was established, after a follow up o 6 years, there have been no reports of new cases of hepatitis B and the incidence of the disease has been declining.
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