Active Vibration Isolation Control: Comparison of Feedback and Feedforward Control Strategies Applied to Coriolis Mass-Flow Meters (I)

In this paper we describe the design, implementation and results of multi degree of freedom (DOF) active vibration control for a Coriolis mass-flow meter (CMFM). Without vibration control, environmental vibrational disturbances results in nanometre movement of the fluid-conveying tube which causes erroneous mass-flow measurements. In order to reduce the transmissibility from external vibrations to the internal tube displacement active vibration control is applied.\ud A comparison of a feedback control strategy (adding virtual mass and skyhook damping) and an adaptive feedforward control strategy is made, taking into account the sensor noise levels. Theoretic results are validated with a multi-DOF experimental setup, showing up to 40 dB reduction of the influence of external vibrations. The amount of reduction is limited by the sensor noise levels

Complexiteit en gebiedsontwikkeling

Dit boek – Complexiteit en gebiedsontwikkeling – vertelt het verhaal over hoe docenten en studenten in het onderwijs en het onderzoek van Hogeschool Van Hall Larenstein omgaan met complexiteit en gebiedsontwikkeling. Het is bedoeld voor iedereen die bij complexe projecten betrokken is, maar vooral voor huidige en toekomstige studenten van de hogeschool die zullen worden opgeleid voor de omgang met complexe projecten

Anterior colporrhaphy does not induce bladder outlet obstruction

We aimed to evaluate if anterior colporrhaphy causes incomplete voiding due to bladder outlet obstruction. Women scheduled for anterior colporrhaphy were asked to undergo multichannel urodynamic investigation before surgery and the first postoperative day. Bladder outlet obstruction was assessed using the Blaivas-Groutz voiding nomogram. Maximum flow rate, detrusor pressure and residual volume were compared between pre- and postoperative measurements and between women with and without an abnormal post-void residual volume (PVR; volume exceeding 150 ml). Seventeen women participated. One woman who was unobstructed before surgery was obstructed after surgery. Overall, detrusor pressure and maximum flow rate before and after surgery did not differ. After surgery, six women had an abnormal PVR, one was unable to void, four were mildly obstructed and one moderately obstructed. Urodynamic investigation the first day after anterior colporrhaphy did not show that anterior colporrhaphy induces bladder outlet obstruction. The explanation for postoperative urinary retention can therefore also lie in non-anatomical causes such as postoperative pain and psychological factor

Feasibility of Live-Performed Music Therapy for Extremely and Very Preterm Infants in a Tertiary NICU

Objective: We aimed to investigate the feasibility of live-performed music therapy for extremely and very preterm infants admitted to the neonatal intensive care unit (NICU), and their parents, starting the 1st-2nd week after birth. They may benefit from live-performed music therapy as comforting non-pharmacological intervention. Study Design: We included infants born before 30 weeks' gestation in a single center NICU study. Live-performed music therapy was provided three times per week, tailored to the infant's medical condition. Parents were actively involved. Feasibility was determined as a combination of participation, drop-out, overstimulation (based on COMFORT-Neo scores), and evaluations of the intervention by parents and nurses (using a questionnaire on perceived effects on the parent, their infant and the NICU sound environment). Results: We included 18 infants (90% participation rate), with a gestational age of median 27 weeks (IQR 26-28 weeks), 61% males. One infant (5.6%) dropped-out. Differences of COMFORT-Neo scores during and after sessions compared with before sessions were non-significant; overstimulation by music therapy did not occur. Parents reported high satisfaction (highest score possible of 7) with the interventions and reported improvements in both infant and their own respiratory rates. Nurses also reported high satisfaction with the intervention and perceived a quieter NICU sound environment during and after sessions. Conclusion: Live-performed music therapy for extremely and very preterm infants is feasible and well-tolerated, and is experienced as an added value to developmental care. Future studies should assess both short-term and long-term effects, to determine whether this intervention should be part of routine care at the NICU and whether it is most beneficial to start shortly after birth

Perception and manipulation of game control

Humans have humorous conversations and interactions. Nowadays our real life existence is integrated with our life in social media, videogames, mixed reality and physical environments that sense our activities and that can adapt appearance and properties due to our activities. There are other inhabitants in these environments, not only human, but also virtual agents and social robots with which we interact and who decide about their participation in activities. In this paper we look at designing humor and humor opportunities in such environments, providing them with a sense of humor, and able to recognize opportunities to generate humorous interactions or events on the fly. Opportunities, made possible by introducing incongruities, can be exploited by the environment itself, or they can be communicated to its inhabitants