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International audienceThis paper proposes a novel quaternion-basedattitude estimator with magnetic, angular rate, and gravity (MARG) sensor arrays. A new structure of a fixed-gaincomplementary filter is designed fusing related sensors. To avoidusing iterative algorithms, the accelerometer-based attitude determination is transformed into a linear system. Stable solutionto this system is obtained via control theory. With only onematrix multiplication, the solution can be computed. Using theincrement of the solution, we design a complementary filter thatfuses gyroscope and accelerometer together. The proposed filteris fast, since it is free of iteration. We name the proposed filter thefast complementary filter (FCF). To decrease significant effectsof unknown magnetic distortion imposing on the magnetometer, a stepwise filtering architecture is designed. The magneticoutput is fused with the estimated gravity from gyroscope andaccelerometer using a second complementary filter when thereis no significant magnetic distortion. Several experiments arecarried out on real hardware to show the performance andsome comparisons. Results show that the proposed FCF canreach the accuracy of Kalman filter. It successfully finds abalance between estimation accuracy and time consumption.Compared with iterative methods, the proposed FCF has muchless convergence speed. Besides, it is shown that the magneticdistortion would not affect the estimated Euler angles

HAART use was associated with increased regression of SIL among HIV-infected women, and among women who used HAART, increased CD4+ T-cell counts were associated with a greater likelihood of regression. However, the majority of cervical lesions among HIV-infected women, even among individuals who used HAART, did not regress to normal.

to 2008, he was a NSERC Postgraduate (Doctor) scholar at the University of New Brunswick. Since 2009, he has been with Siemens Corporate Technology in USA as a power electronics manager. His current research interests include multilevel topologies and controls for utility and industry applications.

A novel hybrid, modular, multilevel converter is presented that utilizes a combination of half-bridge and novel three-level cells where the three-level cells utilize a clamp circuit which, under dc side faults, is capable of blocking fault current thereby avoiding overcurrents in the freewheel diodes. This dc fault blocking capability is demonstrated through simulation and is shown to be as good as the modular multilevel converter which utilizes full-bridge cells but with the added benefits of: lower conduction losses; fewer diode and semiconductor switching devices, and; fewer shoot-through modes. The semiconductor count and conduction loss of the proposed converter are reduced to around 66.5% and 72% of that of modular multilevel converter based on the full-bridge cells respectively, yielding lower semiconductor cost and improved efficiency. Dc fault ridethrough operation is realized without exposing the semiconductors to significant fault currents and overvoltages due to the full dc fault blocking capability of the converter. Index Terms-dc fault blocking, high-voltage dc (HVDC) transmission system, hybrid multilevel converter, modular multilevel converter (MMC), three-level cell, voltage source converter (VSC).