Mario Orlando Oliveira

Bio: Mario Orlando Oliveira is an academic researcher from National University of Misiones. The author has contributed to research in topics: Fault (power engineering) & Wavelet transform. The author has an hindex of 10, co-authored 35 publications receiving 244 citations. Previous affiliations of Mario Orlando Oliveira include Universidade Federal do Rio Grande do Sul & University of Rio Grande.

Cardiac pacing in severe recurrent reflex syncope and tilt-induced asystole.

Abstract: Aim The benefit of cardiac pacing in patients with severe recurrent reflex syncope and asystole induced by tilt testing has not been established. The usefulness of tilt-table test to select candidates for cardiac pacing is controversial. Methods and results We randomly assigned patients aged 40 years or older who had at least two episodes of unpredictable severe reflex syncope during the last year and a tilt-induced syncope with an asystolic pause longer than 3 s, to receive either an active (pacing ON; 63 patients) or an inactive (pacing OFF; 64 patients) dual-chamber pacemaker with closed loop stimulation (CLS). The primary endpoint was the time to first recurrence of syncope. Patients and independent outcome assessors were blinded to the assigned treatment. After a median follow-up of 11.2 months, syncope occurred in significantly fewer patients in the pacing group than in the control group [10 (16%) vs. 34 (53%); hazard ratio, 0.23; P = 0.00005]. The estimated syncope recurrence rate at 1 year was 19% (pacing) and 53% (control) and at 2 years, 22% (pacing) and 68% (control). A combined endpoint of syncope or presyncope occurred in significantly fewer patients in the pacing group [23 (37%) vs. 40 (63%); hazard ratio, 0.44; P = 0.002]. Minor device-related adverse events were reported in five patients (4%). Conclusion In patients aged 40 years or older, affected by severe recurrent reflex syncope and tilt-induced asystole, dual-chamber pacemaker with CLS is highly effective in reducing the recurrences of syncope. Our findings support the inclusion of tilt testing as a useful method to select candidates for cardiac pacing. Study registration ClinicalTrials.gov identifier NCT02324920, Eudamed number CIV-05-013546.

Application of Discrete Wavelet Transform for differential protection of power transformers

Abstract: This paper presents a novel formulation for differential protection of three-phase transformers. The Discrete Wavelet Transform (DWT) is employed to extract transitory features of transformer three-phase differential currents to detect internal faulty conditions. The performance of the proposed algorithm is evaluated through simulation of faulty and non-faulty test cases on a power transformer using ATP/EMTP software. The optimal mother wavelet selection includes performance analysis of different mother wavelets and resolution number of levels. In order to test the formulations performance, the proposed method was implemented on MatLab® environment. Simulated comparative test results with a percentage differential protection with harmonic restraint formulation shows that the proposed technique improves the discrimination performance. Simulated test cases of magnetizing inrush and close by external faults are also presented in order to test the performance of the proposed method in extreme conditions.

Adaptive differential protection of three-phase power transformers based on transient signal analysis

Abstract: This paper presents a three-phase power transformer percentage differential protection formulation based on transient signal analysis. The proposed formulation uses discrete wavelet transforms (DWT) to extract transitory features of non-stationary signals with fast transition, mapping the signal in time–frequency representation. The proposed formulation was implemented on MATLAB® environment and evaluated through a case study using BPA’S ATP/EMTP software. Comparative test results are presented showing that the proposed formulation is highly reliable, fast, accurate and easy for real-life construction.

Climate change effect on very short-term electric load forecasting

Abstract: Climate changes are related to air temperature, relative humidity, wind speed, precipitation level, among others These variables have a large effect on very short-term electricity demand (minutes or hour ahead) In this context, this paper presents a methodology for very short-term load forecasting considering the climatic change impact Therefore, air temperature and relative humidity are related through the Discomfort Index, and the first with the wind speed are linked through the Wind Chill These climate indexes are used in this paper for electric load forecasting together with a multiple regression model The proposed projection methodology was tested computationally and compared with real date obtained from a distribution utility located in southern Brazil The results demonstrate the strong dependence of the evolution of electricity demand with climatic change in the very short-term

Management of Mechanical Vibration and Temperature in Small Wind Turbines Using Zigbee Wireless Network

Abstract: This paper presents the development of a methodology to manage the mechanic vibration and temperature from Small Wind Turbine (SWT). The objective with this research is propose a new diagnostic and protection tool through analysis and monitoring signals of vibration and temperature from wind turbines, aiming predict a need of preventive maintenance and mostly avoids catastrophic failures. For this feature the system will be composed of a Triple Axis accelerometer who will identify vibration, thermocouples to identify the temperatures at critical points of wind turbine, a microcontroller hardware which will make acquisition and processing of signals from sensors and finally a wireless transmission system using technology ZigBee. The post processing is performed remotely through a computer that receives the data submitted via wireless network presenting them to the user via graphical interface. The software of User friendly interface will have the functionality plus online display of received data also the possibility of storing and reporting data rates of vibration and temperature obtained during monitoring. Finally featuring the prototype of the hardware and software as well as some results obtained in experimental scale.

Medscape

Abstract: Secret History: Return of the Black Death Channel 4, 7-8pm In 1348 the Black Death swept through London, killing people within days of the appearance of their first symptoms. Exactly how many died, and why, has long been a mystery. This Secret History documentary follows experts as they pick through the evidence and reveal why the plague killed on such a scale. And they ask, what might be coming next?

2018 ESC Guidelines for the diagnosis and management of syncope

Abstract: Authors/Task Force Members: Michele Brignole* (Chairperson) (Italy), Angel Moya* (Co-chairperson) (Spain), Frederik J. de Lange (The Netherlands), Jean-Claude Deharo (France), Perry M. Elliott (UK), Alessandra Fanciulli (Austria), Artur Fedorowski (Sweden), Raffaello Furlan (Italy), Rose Anne Kenny (Ireland), Alfonso Mart ın (Spain), Vincent Probst (France), Matthew J. Reed (UK), Ciara P. Rice (Ireland), Richard Sutton (Monaco), Andrea Ungar (Italy), and J. Gert van Dijk (The Netherlands)