Design Characteristics of the 224 kW Magdalen Islands VAWT

The evolution of the main design features of the Magdalen Islands vertical axis wind turbine (VAWT) is described. The turbine has a rotor height of 120 ft (36.58 m) and diameter 80 ft (24.38 m). It was operated as a joint project between NRC and Hydro-Quebec in grid-coupled mode from July 1977 to July 1978 when the rotor was destroyed in an accident. The accident, although unfortunate, tested the basic integrity of the design in a gross overspeed condition, and the rotor is being rebuilt with minor modifications. Some directions for future VAWT research are suggested

Advancing the Standards for Unmanned Air System Communications, Navigation and Surveillance

Under NASA program NNA16BD84C, new architectures were identified and developed for supporting reliable and secure Communications, Navigation and Surveillance (CNS) needs for Unmanned Air Systems (UAS) operating in both controlled and uncontrolled airspace. An analysis of architectures for the two categories of airspace and an implementation technology readiness analysis were performed. These studies produced NASA reports that have been made available in the public domain and have been briefed in previous conferences. We now consider how the products of the study are influencing emerging directions in the aviation standards communities. The International Civil Aviation Organization (ICAO) Communications Panel (CP), Working Group I (WG-I) is currently developing a communications network architecture known as the Aeronautical Telecommunications Network with Internet Protocol Services (ATN/IPS). The target use case for this service is secure and reliable Air Traffic Management (ATM) for manned aircraft operating in controlled airspace. However, the work is more and more also considering the emerging class of airspace users known as Remotely Piloted Aircraft Systems (RPAS), which refers to certain UAS classes. In addition, two Special Committees (SCs) in the Radio Technical Commission for Aeronautics (RTCA) are developing Minimum Aviation System Performance Standards (MASPS) and Minimum Operational Performance Standards (MOPS) for UAS. RTCA SC-223 is investigating an Internet Protocol Suite (IPS) and AeroMACS aviation data link for interoperable (INTEROP) UAS communications. Meanwhile, RTCA SC-228 is working to develop Detect And Avoid (DAA) equipment and a Command and Control (C2) Data Link MOPS establishing LBand and C-Band solutions. These RTCA Special Committees along with ICAO CP WG/I are therefore overlapping in terms of the Communication, Navigation and Surveillance (CNS) alternatives they are seeking to provide for an integrated manned- and unmanned air traffic management service as well as remote pilot command and control. This paper presents UAS CNS architecture concepts developed under the NASA program that apply to all three of the aforementioned committees. It discusses the similarities and differences in the problem spaces under consideration in each committee, and considers the application of a common set of CNS alternatives that can be widely applied. As the works of these committees progress, it is clear that the overlap will need to be addressed to ensure a consistent and safe framework for worldwide aviation. In this study, we discuss similarities and differences in the various operational models and show how the CNS architectures developed under the NASA program apply

Stamm- und progenitorzellbasierte Therapieansätze: Aktuelle Entwicklungen zur Behandlung des akuten Myokardinfarkts und der chronischen ischämischen Kardiomyopathie

Zusammenfassung: Die perkutane koronare Revaskularisation sowie eine optimierte medikamentöse Therapie können bei Patienten mit akutem Myokardinfarkt das linksventrikuläre (LV) Remodeling und die LV-Dysfunktion reduzieren. Trotz dieser modernen Therapiestrategien entwickelt ein nicht unerheblicher Teil dieser Patienten ein ungünstiges kardiales Remodeling, das mit einer schlechten Prognose einhergeht. Stamm- und progenitorzellbasierte Ansätze für die Behandlung des akuten Myokardinfarkts und der chronischen ischämischen Kardiomyopathie werden als potenzielle neue therapeutische Optionen intensiv untersucht. Diese Übersicht fasst die aktuellen Entwicklungen in der stamm- und progenitorzellbasierten Therapie bei ischämischer Herzerkrankung zusammen. Dabei erfolgt eine Einschätzung der Reparatur- und Regenerationsfähigkeit verschiedener Stamm- und Progenitorzellpopulationen. Darüber hinaus werden die Vor- und Nachteile der verschiedenen kardialen Applikationsformen der Zellen und mögliche neue Strategien zur Funktionsverbesserung von Stamm- und Progenitorzellen für den Einsatz der zellbasierten kardiovaskulären Therapie dargestell

A Powertrain LQR Torque Compensator with Backlash Handling

This paper derives an LQR anti-jerk controller for an automotive driveline. The time derivative of the drive shaft torque, which is closely related to the vehicle jerk, is used as a virtual system output and regulated to zero. Thereby, the controller does not need a reference model for generation of reference trajectories for the control law evaluation. The controller acts as a torque compensator for the driver’s torque demand which the controller output asymptotically follows. The properties of the controller are discussed and the behavior is illustrated by simulation examples and verified with experiments on a heavy duty truck

Effect of cervical length recovery after laser surgery for twin-twin transfusion syndrome

Objective To evaluate the impact of polyhydramnios on preoperative cervical length and whether cervical length recovery after amnioreduction during selective fetoscopic laser photocoagulation (SFLP) is associated with a greater gestational age at delivery in pregnancies complicated by twin-twin transfusion syndrome (TTTS). Methods Retrospective study of 50 pregnancies complicated by TTTS treated with SFLP between March 2010 and July 2014 at a single center. Preoperative maximum vertical pocket (MVP) was measured along with pre- and postoperative cervical length. A cervical length difference was calculated, with a difference of ± 3 mm considered no change. Results Only 12 (34%) patients showed an increased cervical length after amnioreduction during laser surgery. There was no statistical difference between either negative or positive change in cervical length groups and mean gestational age at delivery (p = 0.82). There also was no correlation between preoperative MVP and preoperative cervical length (p = 0.36) or gestational age at delivery (p = 0.77). However, there was a statistically shorter mean preoperative cervical length in patients who delivered <32 weeks of gestation (3.62 ± 0.66 vs. 4.20 ± 0.85 cm; p = 0.03). Conclusion Severity of polyhydramnios does not correlate with preoperative cervical length, and variability of the cervix postoperatively does not appear to affect gestational age at delivery