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Publikation Quality evaluation methods for wastewater treatment plant data(IWA Publishing, 2008) Thomann, MichaelNon identified systematic errors in data sets can cause severe problems inducing wrong decisions in function control, process modelling or planning of new treatment infrastructure. In this paper statistical methods are shown to identify systematic errors in full-scale WWTP data sets. With a redundant mass balance approach analyzing five different mass balances, systematic errors of about 10%–20% compared to the input fluxes can be identified at a 5%-significance level. A Shewhart control-chart approach to survey the data quality of on-line-sensors allows a statistical as well as a fast graphical analysis of the measurement process. A 19 month data set indicates that NO3−, PO4− and NH4− on-line analyzers in the filter effluent and MLSS sensors in the aeration tanks were not disturbed by any systematic error for 85–95% of the measuring time. The in-control-interval (±3·standard deviation) has a width of ±12–17% (NO3-N), ±35–40% (PO4-P), ±83% (NH4-N) and ±12–15% (TS) of the measured reference value.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Conditioning circuits for nanoscale perpendicular spin transfer torque magnetic tunnel junctions as magnetic sensors(IEEE, 2023) Nicolas, Hugo; Sousa, Ricardo C.; Mora-Hernández, Ariam; Prejbeanu, Ioan-Lucian; Hebrard, Luc; Kammerer, Jean-Baptiste; Pascal, JorisThis article demonstrates a new type of magnetic sensor using a perpendicular spin transfer torque magnetic tunnel junction (MTJ). The sensing element has a cylindrical shape of 50 nm in diameter and is to our knowledge among the smallest magnetic sensor ever reported. This article describes the principle of operation of the sensing element and the associated signal processing electronics, which delivers a signal proportional to the external magnetic field. Experimental results are detailed and compared to the state-of-the-art commercially available integrated magnetic sensors as well as published magnetoresistive sensors based on MTJs with comparable size. The measured sensitivity of the developed sensor is 1.28 V/T, and its dynamic range reaches 80 mT. The measured noise level is 21.8μT/√ Hz. Two different operating principles of the proposed sensor are described and compared, one based on a time-to-digital converter and one based on a pulsewidth-modulated (PWM) signal. Both methods require only standard microelectronics components, which are suitable for monolithic integration of the sensing element with its conditioning electronics. Subsequent improvements of the sensing element as well as conditioning electronics are required to further lower the noise level. The sensing element and its conditioning electronics are compatible with fabrication processes already used in magnetic random access memory fabrication. This opens the way to mass production and addresses various markets, such as consumer electronics, automotive, industrial sensing, physics experiments, or medical devices.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Tracking of a magnetically navigated millirobot with a magnetic-field camera(IEEE, 10.04.2024) Vergne, Céline; Pinto Inácio, José Miguel; Quirin, Thomas; Sargent, David; Madec, Morgan; Pascal, JorisA significant progress has been made in the development of magnetic micromanipulation for minimally invasive surgery. The development of systems to localize millimeter-sized robots during magnetic manipulation without line-of-sight detection remains, however, a challenging task. In this study, we focused on the development of a tracking system aiming to fill this gap. A robot, which consists of a cylindrical magnet of 1-mm diameter, is localized using a 2-D array of 3-D magnetoresistive sensors. The system, also called magnetic-field camera (MFC), provides tracking of the robot with a refresh rate of 2 Hz. The developed tracking algorithm reaches a mean absolute error (MAE) for the position and the orientation of, respectively, 0.56 mm and 5.13° in 2-D. This system can be added to the existing magnetic manipulation systems (MMSs) allowing closed-loop control of the navigation. The performances of the MFC are not affected by an exposure to strong magnetic fields. Exposures up to 3 T have been validated. Increasing the integrability of the MFC into MMSs. The presented tracking system makes it possible to target applications, such as minimally invasive eye surgery or drug delivery. The high spatial and magnetic resolutions allow the tracking of magnetic particles, down to 200- μm diameter, when placed close to the surface. The system could also be suitable for the localization of small objects for 2-D biomanipulation.01A - Beitrag in wissenschaftlicher Zeitschrift